67 results on '"Weier Qi"'
Search Results
2. 3',4'-Dihydroxyflavonol antioxidant attenuates diastolic dysfunction and cardiac remodeling in streptozotocin-induced diabetic m(Ren2)27 rats.
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Fay Lin Khong, Yuan Zhang, Amanda J Edgley, Weier Qi, Kim A Connelly, Owen L Woodman, Henry Krum, and Darren J Kelly
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Medicine ,Science - Abstract
BackgroundDiabetic cardiomyopathy (DCM) is an increasingly recognized cause of chronic heart failure amongst diabetic patients. Both increased reactive oxygen species (ROS) generation and impaired ROS scavenging have been implicated in the pathogenesis of hyperglycemia-induced left ventricular dysfunction, cardiac fibrosis, apoptosis and hypertrophy. We hypothesized that 3',4'-dihydroxyflavonol (DiOHF), a small highly lipid soluble synthetic flavonol, may prevent DCM by scavenging ROS, thus preventing ROS-induced cardiac damage.Methodology/principal findingsSix week old homozygous Ren-2 rats were randomized to receive either streptozotocin or citrate buffer, then further randomized to receive either DiOHF (1 mg/kg/day) by oral gavage or vehicle for six weeks. Cardiac function was assessed via echocardiography and left ventricular cardiac catheterization before the animals were sacrificed and hearts removed for histological and molecular analyses. Diabetic Ren-2 rats showed evidence of diastolic dysfunction with prolonged deceleration time, reduced E/A ratio, and increased slope of end-diastolic pressure volume relationship (EDPVR) in association with marked interstitial fibrosis and oxidative stress (all PConclusionsInhibition of ROS production and action by DiOHF improved diastolic function and reduced myocyte hypertrophy as well as collagen deposition. These findings suggest the potential clinical utility of antioxidative compounds such as flavonols in the prevention of diabetes-associated cardiac dysfunction.
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- 2011
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3. Characterization of Glycolytic Enzymes and Pyruvate Kinase M2 in Type 1 and 2 Diabetic Nephropathy
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Monika A. Niewczas, Peter S. Amenta, Thorsten Sadowski, Hetal Shah, Vanessa Bahnam, Aimo Kannt, Kyoungmin Park, Weier Qi, George L. King, Daniel Gordin, David Pober, Hillary A. Keenan, Hui Pan, Yutong Dong, Ronald St-Louis, Takanori Shinjo, Samantha M. Paniagua, Liane J. Tinsley, I-Hsien Wu, Megan J. Brissett, and Jonathan M. Dreyfuss
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Male ,Proteomics ,Endocrinology, Diabetes and Metabolism ,Kidney Glomerulus ,Type 2 diabetes ,urologic and male genital diseases ,Kidney ,Cohort Studies ,Diabetic nephropathy ,0302 clinical medicine ,Diabetic Nephropathies ,030212 general & internal medicine ,Aged, 80 and over ,Middle Aged ,Enzymes ,Mitochondria ,medicine.anatomical_structure ,Disease Progression ,Female ,Autopsy ,Metabolic Networks and Pathways ,Glomerular Filtration Rate ,medicine.medical_specialty ,Pyruvate Kinase ,030209 endocrinology & metabolism ,PKM2 ,03 medical and health sciences ,Downregulation and upregulation ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,medicine ,Humans ,Metabolomics ,Renal Insufficiency, Chronic ,Pathophysiology/Complications ,Aged ,Advanced and Specialized Nursing ,business.industry ,Kidney metabolism ,medicine.disease ,Diabetes Mellitus, Type 1 ,Glucose ,Endocrinology ,Diabetes Mellitus, Type 2 ,Mitochondrial biogenesis ,Case-Control Studies ,business ,Biomarkers - Abstract
OBJECTIVE Elevated glycolytic enzymes in renal glomeruli correlated with preservation of renal function in the Medalist Study, individuals with ≥50 years of type 1 diabetes. Specifically, pyruvate kinase M2 (PKM2) activation protected insulin-deficient diabetic mice from hyperglycemia-induced glomerular pathology. This study aims to extend these findings in a separate cohort of individuals with type 1 and type 2 diabetes and discover new circulatory biomarkers for renal protection through proteomics and metabolomics of Medalists’ plasma. We hypothesize that increased glycolytic flux and improved mitochondrial biogenesis will halt the progression of diabetic nephropathy. RESEARCH DESIGN AND METHODS Immunoblots analyzed selected glycolytic and mitochondrial enzymes in postmortem glomeruli of non-Medalists with type 1 diabetes (n = 15), type 2 diabetes (n = 19), and no diabetes (n = 5). Plasma proteomic (SOMAscan) (n = 180) and metabolomic screens (n = 214) of Medalists with and without stage 3b chronic kidney disease (CKD) were conducted and significant markers validated by ELISA. RESULTS Glycolytic (PKM1, PKM2, and ENO1) and mitochondrial (MTCO2) enzymes were significantly elevated in glomeruli of CKD− versus CKD+ individuals with type 2 diabetes. Medalists’ plasma PKM2 correlated with estimated glomerular filtration rate (r2 = 0.077; P = 0.0002). Several glucose and mitochondrial enzymes in circulation were upregulated with corresponding downregulation of toxic metabolites in CKD-protected Medalists. Amyloid precursor protein was also significantly upregulated, tumor necrosis factor receptors downregulated, and both confirmed by ELISA. CONCLUSIONS Elevation of enzymes involved in the metabolism of intracellular free glucose and its metabolites in renal glomeruli is connected to preserving kidney function in both type 1 and type 2 diabetes. The renal profile of elevated glycolytic enzymes and reduced toxic glucose metabolites is reflected in the circulation, supporting their use as biomarkers for endogenous renal protective factors in people with diabetes.
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- 2019
4. 309-OR: IGF-1 Receptors, Not Insulin Receptors, on Mesangial Cells Are Accelerating Mesangial Expansion and Albuminuria in Streptozotocin-Induced Diabetic Mice
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Yasutaka Maeda, Hisashi Yokomizo, Takanori Shinjo, Ronald St-Louis, Atsushi Ishikado, Kyoungmin Park, George L. King, Weier Qi, and Qian Li
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MAPK/ERK pathway ,medicine.medical_specialty ,biology ,Chemistry ,Kinase ,Endocrinology, Diabetes and Metabolism ,Insulin ,medicine.medical_treatment ,Streptozotocin ,medicine.disease ,Insulin receptor ,Endocrinology ,Internal medicine ,Diabetes mellitus ,Internal Medicine ,medicine ,biology.protein ,Receptor ,Protein kinase B ,medicine.drug - Abstract
Clinical studies have suggested that loss of insulin’s action and excessive IGF-1 levels in the glomeruli elevate the risk for diabetic kidney disease (DKD). To define the potential pathogenic role of IGF-1 and insulin signaling in DKD, we generated mice with selective loss of insulin receptor (IR) or IGF-1 receptor (IGF-1R) in the mesangial cells (MCs) by cross breeding IRflox/flox mice with Sm22α-Cre mice (SMIRKO) or IGF-1Rflox/flox mice with Myh11-Cre mice (SMIGF1RKO), and examined urinary albumin excretion (ACR) and mesangial expansion with 6 month duration of streptozotocin (STZ)-induced diabetes. IGF-1 levels were significantly increased by 1.5 fold in the renal cortex, but not in the plasma of all three types of diabetic mice. Diabetes induced elevation of ACR (2.0 fold), glomerular size and mesangial expansion (2.1 fold), in parallel with increased glomerular expressions of fibrosis-related (Tgfβ1, fibronectin and Col3a) and matrix (Has2) genes by 2-3 fold, significantly, in Wt and SMIRKO mice, but were prevented in diabetic SMIGF1RKO mice. In cultured MCs, IGF-1, at physiological levels, and insulin, only at supra-physiological levels, induced the expressions of Has2 (3.8 fold) and Tgfβ1 (1.7 fold). Deletion of IGF-1R, but not IR, in MCs inhibited both IGF-1 and insulin-induced expressions of Has2. Inhibitor of MAP kinase pathway, but not inhibitor of PI3 kinase reduced insulin or IGF-1-induced expressions of Has2 in MCs. IGF-1-induced phosphorylations of IGF-1R (39 fold), Akt (34 fold) and Erk/MAPK (8 fold) were significantly inhibited in both IR or IGF-1R-deleted MCs. Insulin-induced phosphorylations of IR-β (11 fold) and Akt (27 fold) were also decreased in IR-deleted MCs, but surprisingly increased in IGF-1R-deleted MCs. Thus, MAPK activation by elevated glomerular IGF-1 levels via IGF-1R, but not IR, on MCs, may contribute to the pathogenesis of DKD through induction of Has2 and fibrotic genes. Disclosure A. Ishikado: Employee; Self; Sunstar Group. Employee; Spouse/Partner; Sunstar Group. T. Shinjo: None. H. Yokomizo: None. Y. Maeda: None. K. Park: None. W. Qi: None. R. St-Louis: None. Q. Li: None. G.L. King: Research Support; Self; Janssen Pharmaceuticals, Inc.
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- 2020
5. Pyruvate kinase M2 activation may protect against the progression of diabetic glomerular pathology and mitochondrial dysfunction
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Alison Burkart, Anja Pfenninger, Christopher Cahill, Atsushi Ishikado, Weier Qi, Lawrence J. Coppey, Isaac E. Stillman, Chong Wee Liew, Hillary A. Keenan, Matthew G. Vander Heiden, Monika A. Niewczas, Thorsten Sadowski, Aimo Kannt, Stephanie M. Hastings, Samuel M. Lockhart, Guifen Qiang, David M. Pober, Qian Li, Edward P. Feener, Liane J. Tinsley, I-Hsien Wu, Mark A. Yorek, William J. Israelsen, Peter S. Amenta, George L. King, and Robert Stanton
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Male ,Proteomics ,0301 basic medicine ,Pathology ,Kidney Glomerulus ,Fluorescent Antibody Technique ,Kidney ,Diabetic nephropathy ,Mice ,Diabetic Nephropathies ,Glycolysis ,Aged, 80 and over ,Membrane Potential, Mitochondrial ,Mice, Knockout ,Organelle Biogenesis ,Podocytes ,General Medicine ,Middle Aged ,Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ,Mitochondria ,Gene Knockdown Techniques ,Female ,medicine.medical_specialty ,Nitric Oxide Synthase Type III ,Blotting, Western ,Pyruvate Kinase ,PKM2 ,Real-Time Polymerase Chain Reaction ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Diabetes Mellitus, Experimental ,03 medical and health sciences ,Downregulation and upregulation ,Diabetes mellitus ,Internal medicine ,Diabetes Mellitus ,medicine ,Animals ,Humans ,Metabolomics ,Aged ,business.industry ,Kidney metabolism ,medicine.disease ,Glucose ,030104 developmental biology ,Endocrinology ,Mitochondrial biogenesis ,Reactive Oxygen Species ,business ,Pyruvate kinase - Abstract
Diabetic nephropathy (DN) is a major cause of end-stage renal disease, and therapeutic options for preventing its progression are limited. To identify novel therapeutic strategies, we studied protective factors for DN using proteomics on glomeruli from individuals with extreme duration of diabetes (ł50 years) without DN and those with histologic signs of DN. Enzymes in the glycolytic, sorbitol, methylglyoxal and mitochondrial pathways were elevated in individuals without DN. In particular, pyruvate kinase M2 (PKM2) expression and activity were upregulated. Mechanistically, we showed that hyperglycemia and diabetes decreased PKM2 tetramer formation and activity by sulfenylation in mouse glomeruli and cultured podocytes. Pkm-knockdown immortalized mouse podocytes had higher levels of toxic glucose metabolites, mitochondrial dysfunction and apoptosis. Podocyte-specific Pkm2-knockout (KO) mice with diabetes developed worse albuminuria and glomerular pathology. Conversely, we found that pharmacological activation of PKM2 by a small-molecule PKM2 activator, TEPP-46, reversed hyperglycemia-induced elevation in toxic glucose metabolites and mitochondrial dysfunction, partially by increasing glycolytic flux and PGC-1α mRNA in cultured podocytes. In intervention studies using DBA2/J and Nos3 (eNos) KO mouse models of diabetes, TEPP-46 treatment reversed metabolic abnormalities, mitochondrial dysfunction and kidney pathology. Thus, PKM2 activation may protect against DN by increasing glucose metabolic flux, inhibiting the production of toxic glucose metabolites and inducing mitochondrial biogenesis to restore mitochondrial function.
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- 2017
6. SHP-1 activation inhibits vascular smooth muscle cell proliferation and intimal hyperplasia in a rodent model of insulin resistance and diabetes
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Weier Qi, Kevin Croce, Yu Xia, Xuanchun Wang, George L. King, Samuel M. Lockhart, Christian Rask-Madsen, Lars Melholt Rasmussen, Qian Li, Mogher Khamaisi, and Chong Wee Liew
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0301 basic medicine ,medicine.medical_specialty ,animal structures ,Intimal hyperplasia ,Vascular smooth muscle ,Endocrinology, Diabetes and Metabolism ,Blotting, Western ,Myocytes, Smooth Muscle ,chemical and pharmacologic phenomena ,Mice, Transgenic ,Protein tyrosine phosphatase ,Real-Time Polymerase Chain Reaction ,Muscle, Smooth, Vascular ,Article ,Mice ,03 medical and health sciences ,Insulin resistance ,Restenosis ,Cell Movement ,Internal medicine ,Diabetes mellitus ,Journal Article ,Internal Medicine ,Animals ,Humans ,Medicine ,Cell Proliferation ,Hyperplasia ,business.industry ,Cell growth ,Protein Tyrosine Phosphatase, Non-Receptor Type 6 ,Cell Cycle ,hemic and immune systems ,medicine.disease ,Rats ,Rats, Zucker ,3. Good health ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,embryonic structures ,biological phenomena, cell phenomena, and immunity ,Insulin Resistance ,Tunica Intima ,business ,Proto-oncogene tyrosine-protein kinase Src - Abstract
AIMS/HYPOTHESIS: Accelerated migration and proliferation of vascular smooth muscle cells (VSMCs) enhances arterial restenosis after angioplasty in insulin resistance and diabetes. Elevation of Src homology 2-containing protein tyrosine phosphatase 1 (SHP-1) induces apoptosis in the microvasculature. However, the role of SHP-1 in intimal hyperplasia and restenosis has not been clarified in insulin resistance and diabetes.METHODS: We used a femoral artery wire injury mouse model, rodent models with insulin resistance and diabetes, and patients with type 2 diabetes. Further, we modulated SHP-1 expression using a transgenic mouse that overexpresses SHP-1 in VSMCs (Shp-1-Tg). SHP-1 agonists were also employed to study the molecular mechanisms underlying the regulation of SHP-1 by oxidised lipids.RESULTS: Mice fed a high-fat diet (HFD) exhibited increased femoral artery intimal hyperplasia and decreased arterial SHP-1 expression compared with mice fed a regular diet. Arterial SHP-1 expression was also decreased in Zucker fatty rats, Zucker diabetic fatty rats and in patients with type 2 diabetes. In primary cultured VSMCs, oxidised LDL suppressed SHP-1 expression by activating Mek-1 (also known as Map2k1) and increased DNA methylation of the Shp-1 promoter. VSMCs from Shp-1-Tg mice exhibited impaired platelet-derived growth factor (PDGF)-stimulated tyrosine phosphorylation with a concomitant decrease in PDGF-stimulated VSMC proliferation and migration. Similarly, HFD-fed Shp-1-Tg mice and mice treated with the SHP-1 inducer, Icariside II, were protected from the development of intimal hyperplasia following wire injury.CONCLUSIONS/INTERPRETATION: Suppression of SHP-1 by oxidised lipids may contribute to the excessive VSMC proliferation, inflammatory cytokine production and intimal hyperplasia observed in arteries from diabetes and insulin resistance. Augmenting SHP-1 levels is a potential therapeutic strategy to maintain stent patency in patients with insulin resistance and diabetes.
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- 2016
7. Homozygous receptors for insulin and not IGF-1 accelerate intimal hyperplasia in insulin resistance and diabetes
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Weier Qi, Hisashi Yokomizo, Yu Xia, Atsushi Ishikado, Weikang Cai, Qian Huang, Kyoungmin Park, Jialin Fu, Qian Li, George L. King, Christian Rask-Madsen, and C. Ronald Kahn
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Male ,0301 basic medicine ,Intimal hyperplasia ,medicine.medical_treatment ,General Physics and Astronomy ,Muscle, Smooth, Vascular ,Receptor, IGF Type 1 ,Mice ,0302 clinical medicine ,Insulin ,Insulin-Like Growth Factor I ,lcsh:Science ,Receptor ,Vascular diseases ,Multidisciplinary ,biology ,Chemistry ,Homozygote ,Hyperplasia ,Femoral Artery ,Signal transduction ,Signal Transduction ,medicine.medical_specialty ,Science ,030209 endocrinology & metabolism ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Insulin resistance ,Internal medicine ,Diabetes Mellitus ,medicine ,Animals ,Insulin-like growth factor 1 receptor ,Insulin signalling ,General Chemistry ,medicine.disease ,Receptor, Insulin ,Mice, Inbred C57BL ,Disease Models, Animal ,Insulin receptor ,030104 developmental biology ,Endocrinology ,biology.protein ,lcsh:Q ,Insulin Resistance ,Hyaluronan Synthases - Abstract
Insulin and IGF-1 actions in vascular smooth muscle cells (VSMC) are associated with accelerated arterial intima hyperplasia and restenosis after angioplasty, especially in diabetes. To distinguish their relative roles, we delete insulin receptor (SMIRKO) or IGF-1 receptor (SMIGF1RKO) in VSMC and in mice. Here we report that intima hyperplasia is attenuated in SMIRKO mice, but not in SMIGF1RKO mice. In VSMC, deleting IGF1R increases homodimers of IR, enhances insulin binding, stimulates p-Akt and proliferation, but deleting IR decreases responses to insulin and IGF-1. Studies using chimeras of IR(extracellular domain)/IGF1R(intracellular-domain) or IGF1R(extracellular domain)/IR(intracellular-domain) demonstrate homodimer IRα enhances insulin binding and signaling which is inhibited by IGF1Rα. RNA-seq identifies hyaluronan synthase2 as a target of homo-IR, with its expression increases by IR activation in SMIGF1RKO mice and decreases in SMIRKO mice. Enhanced intima hyperplasia in diabetes is mainly due to insulin signaling via homo-IR, associated with increased Has2 expression., Both insulin and IGF-1 signaling have been implicated in arterial intimal hyperplasia. Here the authors dissect the relative contributions of insulin and IGF-1 receptors, showing that homodimers of insulin receptors, but not IGF-1 receptor, induce proliferation of vascular smooth muscle cells.
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- 2019
8. Activation of PKM2 Protects against Diabetic Kidney Disease from Mice to Men
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Jonathan M. Dreyfuss, Ronald St-Louis, Weier Qi, Hetal Shah, Megan J. Brissett, Daniel Gordin, Aimo Kannt, David M. Pober, Liane J. Tinsley, Andrzej S. Krolewski, Thorsten Sadowski, George L. King, Takanori Shinjo, Hillary A. Keenan, Monika A. Niewczas, and Hui Pan
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0301 basic medicine ,medicine.medical_specialty ,Type 1 diabetes ,Kidney ,business.industry ,Endocrinology, Diabetes and Metabolism ,Renal function ,030209 endocrinology & metabolism ,Type 2 diabetes ,CCL2 ,medicine.disease ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,medicine.anatomical_structure ,In vivo ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,Medicine ,PPARGC1A ,business - Abstract
We have reported that up-regulation of PKM2 in renal glomeruli isolated from patients with more than 50 years of type 1 diabetes (Joslin Medalist Study) correlated with preservation of renal function even in the presence of chronic hyperglycemia. Further, pharmacological activation of PKM2 in T1D mice and podocyte-specific deletion of PKM2 in cultured cells and in vivo strongly showed that PKM2 activation protects renal glomeruli from hyperglycemia/diabetes induced damage (Nat. Med 2017). To confirm these findings in type 1 and type 2 diabetes, we performed the following: 1. We showed the protein expressions of glycolytic (PKM1, PKM2, ENO1) and mitochondrial (MTCO2) enzymes to be significantly elevated in glomeruli of post mortem kidneys in people with T2D without DN compared to those with DN, or nondiabetic controls. 2. Plasma PKM2 levels (SomaLogic aptamer assay) in the Medalists (n=180) correlated with albumin-to-creatinine ratio (ACR;p=0.03) and eGFR (p=0.0002) at baseline. In a replication cohort (n=219) of patients with T1D in the longitudinal Joslin Kidney Study (JKS) baseline plasma PKM2 also correlated with ACR (p=0.0001). High baseline plasma PKM2 in JKS was independently associated with a slower decline in eGFR (p=0.004) and a slower progression to end-stage renal disease (p=0.0002). 3. TEPP-46, a PKM2 activator, prevented diabetes induced increases in mRNA expression of pro-fibrotic (Col3a1, Fn1, TGFb1) and inflammatory (Ccl2) genes, and enhanced key mitochondrial protein (Ppargc1a) in uninephrectomized T2D db/db mice. No differences in ACR were observed between TEPP-46 treated and untreated diabetic mice. These findings support the hypothesis that PKM2 activation may protect or even reverse the initiation and progression of diabetic glomerular dysfunction and pathology in both T1D and T2D, suggesting that activating PKM2 could be a clinically effective therapeutic target to stop the progression of DN. Disclosure D. Gordin: None. T. Shinjo: None. R. St-Louis: None. W. Qi: None. L.J. Tinsley: None. D.M. Pober: None. M.J. Brissett: None. M. Niewczas: None. J. Dreyfuss: None. H. Pan: None. T. Sadowski: Employee; Self; Sanofi. A. Kannt: Employee; Self; Sanofi. Stock/Shareholder; Self; Sanofi. H. Shah: None. H.A. Keenan: Research Support; Self; Sanofi. Employee; Self; Sanofi Genzyme. A. Krolewski: None. G.L. King: Research Support; Self; Sanofi-Aventis.
- Published
- 2018
9. Preservation of renal function in chronic diabetes by enhancing glomerular glucose metabolism
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Daniel Gordin, Weier Qi, George L. King, and Qian Li
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0301 basic medicine ,medicine.medical_specialty ,Renal function ,Type 2 diabetes ,030204 cardiovascular system & hematology ,PKM2 ,Carbohydrate metabolism ,urologic and male genital diseases ,Kidney ,Article ,Diabetic nephropathy ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Diabetes mellitus ,Drug Discovery ,medicine ,Animals ,Humans ,Glycolysis ,Diabetic Nephropathies ,Genetics (clinical) ,business.industry ,medicine.disease ,030104 developmental biology ,Endocrinology ,Glucose ,Chronic Disease ,Molecular Medicine ,business ,Pyruvate kinase - Abstract
Diabetic nephropathy (DN) affects approximately 30–40% of patients with type 1 (T1DM) and type 2 diabetes (T2DM). It is a major cause of end-stage renal disease (ESRD) for the developed world. Hyperglycemia and genetics are major causal factors for the initiation and progression of DN. Multiple abnormalities in glucose and mitochondrial metabolism induced by diabetes likely contribute to the severity of DN. Recent clinical studies in people with extreme duration of T1DM (> 50 years, Joslin Medalist Study) have supported the importance of endogenous protective factors to neutralize the toxic effects of hyperglycemia on renal and other vascular tissues. Using renal glomeruli from these patients (namely Medalists) with and without DN, we have shown the importance of increased glycolytic flux in decreasing the accumulation of glucose toxic metabolites, improving mitochondrial function, survival of glomerular podocytes, and reducing glomerular pathology. Activation of a key glycolytic enzyme, pyruvate kinase M2 (PKM2), resulted in the normalization of renal hemodynamics and mitochondrial and glomerular dysfunction, leading to the mitigation of glomerular pathologies in several mouse models of DN.
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- 2017
10. Regulation of Macrophage Apoptosis and Atherosclerosis by Lipid-Induced PKCδ Isoform Activation
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Weier Qi, Jialin Fu, Motonobu Matsumoto, George L. King, Hisashi Yokomizo, Xuanchun Wang, Christian Rask-Madsen, Kyoungmin Park, Mogher Khamaisi, Yu Xia, and Qian Li
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0301 basic medicine ,Apolipoprotein E ,Male ,medicine.medical_specialty ,Physiology ,Apoptosis ,Hyperlipidemias ,Biology ,Diet, High-Fat ,Article ,Proinflammatory cytokine ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Insulin resistance ,Internal medicine ,Hyperlipidemia ,medicine ,Macrophage ,Animals ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Mice, Knockout ,Macrophages ,medicine.disease ,Atherosclerosis ,Rats ,Rats, Zucker ,Enzyme Activation ,Isoenzymes ,Mice, Inbred C57BL ,Protein Kinase C-delta ,030104 developmental biology ,Endocrinology ,030220 oncology & carcinogenesis ,Insulin Resistance ,Cardiology and Cardiovascular Medicine - Abstract
Rationale: Activation of monocytes/macrophages by hyperlipidemia associated with diabetes mellitus and obesity contributes to the development of atherosclerosis. PKCδ (protein kinase C δ) expression and activity in monocytes were increased by hyperlipidemia and diabetes mellitus with unknown consequences to atherosclerosis. Objective: To investigate the effect of PKCδ activation in macrophages on the severity of atherosclerosis. Methods and Results: PKCδ expression and activity were increased in Zucker diabetic rats. Mice with selective deletion of PKCδ in macrophages were generated by breeding PKCδ flox/flox mice with LyzM-Cre and ApoE −/ − mice (MPKCδKO/ApoE −/− mice) and studied in atherogenic (AD) and high-fat diet (HFD). Mice fed AD and HFD exhibited hyperlipidemia, but only HFD-fed mice had insulin resistance and mild diabetes mellitus. Surprisingly, MPKCδKO/ApoE −/− mice exhibited accelerated aortic atherosclerotic lesions by 2-fold versus ApoE −/− mice on AD or HFD. Splenomegaly was observed in MPKCδKO/ApoE −/− mice on AD and HFD but not on regular chow. Both the AD or HFD increased macrophage number in aortic plaques and spleen by 1.7- and 2-fold, respectively, in MPKCδKO/ApoE −/− versus ApoE −/− mice because of decreased apoptosis (62%) and increased proliferation (1.9-fold), and not because of uptake, with parallel increased expressions of inflammatory cytokines. Mechanisms for the increased macrophages in MPKCδKO/ApoE −/− were associated with elevated phosphorylation levels of prosurvival cell-signaling proteins, Akt and FoxO3a, with reduction of proapoptotic protein Bim associated with PKCδ induced inhibition of P85/PI3K. Conclusions: Accelerated development of atherosclerosis induced by insulin resistance and hyperlipidemia may be partially limited by PKCδ isoform activation in the monocytes, which decreased its number and inflammatory responses in the arterial wall.
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- 2017
11. Implications of Treatment That Target Protective Mechanisms Against Diabetic Nephropathy
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George L. King, Akira Mima, and Weier Qi
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Glycation End Products, Advanced ,Vascular Endothelial Growth Factor A ,Platelet-derived growth factor ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Bioinformatics ,Antioxidants ,Article ,Diabetic nephropathy ,chemistry.chemical_compound ,Diabetes mellitus ,medicine ,Humans ,Insulin ,Diabetic Nephropathies ,Dyslipidemias ,Platelet-Derived Growth Factor ,business.industry ,Growth factor ,medicine.disease ,Vascular endothelial growth factor ,Vascular endothelial growth factor A ,chemistry ,Nephrology ,Hyperglycemia ,Immunology ,business ,Dyslipidemia - Abstract
Diabetes results in vascular changes and dysfunction, and vascular complications are the leading cause of morbidity and mortality in diabetic patients. There has been a continual increase in the number of diabetic nephropathy patients and epidemic increases in the number of patients progressing to end-stage renal diseases. To identify targets for therapeutic intervention, most studies have focused on understanding how abnormal levels of glucose metabolites cause diabetic nephropathy, which is of paramount importance in devising strategies to combat the development and progression of diabetic nephropathy. However, less studied than the systemic toxic mechanisms, hyperglycemia and dyslipidemia might inhibit the endogenous vascular protective factors such as insulin, vascular endothelial growth factor, and platelet-derived growth factor. In this review, we highlight the importance of enhancing endogenous protective factors to prevent or delay diabetic nephropathy.
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- 2012
12. Cation-independent mannose 6-phosphate receptor inhibitor (PXS25) inhibits fibrosis in human proximal tubular cells by inhibiting conversion of latent to active TGF-β1
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Xin-Ming Chen, Carol A. Pollock, Diego G. Silva, Muh Geot Wong, Weier Qi, and Usha Panchapakesan
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Collagen Type IV ,medicine.medical_specialty ,Cell Survival ,Physiology ,medicine.medical_treatment ,Blotting, Western ,Receptors, Cytoplasmic and Nuclear ,Enzyme-Linked Immunosorbent Assay ,Smad2 Protein ,Biology ,Receptor, IGF Type 2 ,Cell Line ,Kidney Tubules, Proximal ,Transforming Growth Factor beta1 ,Extracellular matrix ,Fibrosis ,Internal medicine ,medicine ,Humans ,Diabetic Nephropathies ,RNA, Messenger ,Hypoxia ,Receptor ,Cell Proliferation ,Mannosephosphates ,Reverse Transcriptase Polymerase Chain Reaction ,Cell growth ,medicine.disease ,Fibronectins ,Cell biology ,Blot ,Glucose ,Endocrinology ,Cytokine ,Matrix Metalloproteinase 9 ,Cell culture ,Hyperglycemia ,Transforming growth factor - Abstract
Hyperglycemia and hypoxia have independent and convergent roles in the development of renal disease. Transforming growth factor-β1(TGF-β1) is a key cytokine promoting the production of extracellular matrix proteins. The cationic-independent mannose 6-phosphate receptor (CI-M6PR) is a membrane protein that binds M6P-containing proteins. A key role is to activate latent TGF-β1. PXS25, a novel CI-MPR inhibitor, has antifibrotic properties in skin fibroblasts, but its role in renal fibrosis is unclear. The aim was to study the role of PXS25 in matrix protein production under high glucose ± hypoxic conditions in human proximal tubule (HK-2) cells. HK-2 cells were exposed to high glucose (30 mM) ± 100 μM PXS25 in both normoxic (20% O2) and hypoxic (1% O2) conditions for 72 h. Cellular fibronectin, collagen IV, and matrix metalloproteinase-2 (MMP-2) and MMP-9 were assessed. Total and active TGF-β1were measured by ELISA. High glucose and hypoxia independently induced TGF-β1production. Active TGF-β1, but not total TGF-β1was reduced with concurrent PXS25 in the presence of high glucose, but not in hyperglycemia+hypoxia conditions. Hyperglycemia induced fibronectin and collagen IV production ( P < 0.05), as did hypoxia, but only hyperglycemia-induced increases in matrix proteins were suppressed by concurrent PXS25 exposure. High glucose induced MMP-2 and -9 in normoxic and hypoxic conditions, which was not modified in the presence of PXS25. High glucose and hypoxia can independently induce endogenous active TGF-β1production in human proximal tubular cells. PXS25 inhibits conversion of high glucose-induced release of active TGF-β1, only in the absence of hypoxia.
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- 2011
13. The roles of Kruppel-like factor 6 and peroxisome proliferator-activated receptor-γ in the regulation of macrophage inflammatory protein-3α at early onset of diabetes
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Christina Y.R. Tan, Xin-Ming Chen, Carol A. Pollock, Darren J. Kelly, John Holian, and Weier Qi
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Male ,Kidney Cortex ,Kruppel-Like Transcription Factors ,Peroxisome proliferator-activated receptor ,Biology ,Biochemistry ,Diabetes Mellitus, Experimental ,Rats, Sprague-Dawley ,Downregulation and upregulation ,Proto-Oncogene Proteins ,Kruppel-Like Factor 6 ,Transcriptional regulation ,Animals ,Humans ,Gene silencing ,Gene Silencing ,Promoter Regions, Genetic ,Macrophage inflammatory protein ,Transcription factor ,Regulation of gene expression ,chemistry.chemical_classification ,Chemokine CCL20 ,Cell Biology ,Rats ,PPAR gamma ,Glucose ,Gene Expression Regulation ,chemistry ,Cancer research ,Thiazolidinediones ,Signal transduction ,Protein Binding - Abstract
Macrophage inflammatory protein-3 alpha (MIP-3α) is known to be upregulated early in the development of diabetic nephropathy (DN). However, the transcriptional regulation of MIP-3α is unknown. We previously demonstrated that the transcription factors KLF6 and PPAR-γ play key roles in regulating renal fibrotic and inflammatory responses to factors inherent in diabetes mellitus. Hence we determined the role of these transcription factors in regulating MIP-3α expression. HK-2 cells and STZ-induced diabetic rats were used. siRNAs, over-expressing constructs and CHIP promoter binding assays were used to determine the role of KLF6 and PPAR-γ in MIP-3α transcriptional regulation. KLF6 overexpression increased MIP-3α which was inhibited by concurrent exposure to PPAR-γ agonists. PPAR-γ agonists attenuated high glucose-induced MIP-3α secretion. Furthermore, MIP-3α secretion was up-regulated in PPAR-γ silenced cells, suggesting both KLF6 and PPAR-γ antagonistically regulate high glucose-induced MIP-3α secretion. The CHIP promoter binding assay confirmed that PPAR-γ binds to the MIP-3α promoter and negatively regulates MIP-3α expression. PPAR-γ agonists increased the binding activity of the PPAR-γ-MIP-3α promoter. In contrast, promoter binding activity decreased in KLF6 over-expressing cells. PPAR-γ decreased in KLF6 over-expressing cells and increased in KLF6 silenced cells, while PPAR-γ siRNA had no effect on KLF6 expression, suggesting that KLF6 acted upstream of PPAR-γ in the regulation of MIP-3α. In diabetic rats, renal MIP-3α and the macrophage marker ED-1 expression increased, which was inhibited by exposure to PPAR-γ agonists. The recognition of MIP-3α as a significant pathogenic mediator in diabetic nephropathy reaffirms the increasingly recognized role of inflammation in the progression of DN. Targeting pro-inflammatory chemokine MIP-3α and its signaling pathways will provide novel strategy to treat diabetic kidney disease.
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- 2011
14. Ramipril retards development of aortic valve stenosis in a rabbit model: mechanistic considerations
- Author
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Ronald D. Wuttke, Jennifer A. Kennedy, John D. Horowitz, H. Weedon, Doan T.M. Ngo, Malcolm D. Smith, Yuan Zhang, Weier Qi, Darren J. Kelly, Irene Stafford, and Aaron L. Sverdlov
- Subjects
Pharmacology ,Aortic valve ,Ramipril ,medicine.medical_specialty ,Heart disease ,Endothelium ,Biology ,medicine.disease ,chemistry.chemical_compound ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Aortic valve stenosis ,Internal medicine ,ACE inhibitor ,medicine ,Cardiology ,Endothelial dysfunction ,Asymmetric dimethylarginine ,medicine.drug - Abstract
BACKGROUND AND PURPOSE Aortic valve stenosis (AVS) is associated with significant cardiovascular morbidity and mortality. To date, no therapeutic modality has been shown to be effective in retarding AVS progression. We evaluated the effect of angiotensin-converting enzyme inhibition with ramipril on disease progression in a recently developed rabbit model of AVS. EXPERIMENTAL APPROACH The effects of 8 weeks of treatment with either vitamin D2 at 25 000 IU for 4 days a week alone or in combination with ramipril (0.5 mg·kg−1) on aortic valve structure and function were examined in New Zealand white rabbits. Echocardiographic aortic valve backscatter (AVBS) and aortic valve : outflow tract flow velocity ratio were utilized to quantify changes in valve structure and function. KEY RESULTS Treatment with ramipril significantly reduced AVBS and improved aortic valve : outflow tract flow velocity ratio. The intravalvular content of the pro-oxidant thioredoxin-interacting protein was decreased significantly with ramipril treatment. Endothelial function, as measured by asymmetric dimethylarginine concentrations and vascular responses to ACh, was improved significantly with ramipril treatment. CONCLUSIONS AND IMPLICATIONS Ramipril retards the development of AVS, reduces valvular thioredoxin-interacting protein accumulation and limits endothelial dysfunction in this animal model. These findings provide important insights into the mechanisms of AVS development and an impetus for future human studies of AVS retardation using an angiotensin-converting enzyme inhibitor.
- Published
- 2011
15. Tranilast attenuates the up-regulation of thioredoxin-interacting protein and oxidative stress in an experimental model of diabetic nephropathy
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Sih Min Tan, Yuan Zhang, Weier Qi, Darren J. Kelly, and Alison J. Cox
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Collagen Type IV ,medicine.medical_specialty ,Luminescence ,Thioredoxin-Interacting Protein ,Tranilast ,Cell Cycle Proteins ,medicine.disease_cause ,Antioxidants ,Immunoenzyme Techniques ,Diabetic nephropathy ,Fibrosis ,Internal medicine ,Diabetes mellitus ,medicine ,Albuminuria ,Animals ,Diabetic Nephropathies ,ortho-Aminobenzoates ,RNA, Messenger ,In Situ Hybridization ,Transplantation ,Reverse Transcriptase Polymerase Chain Reaction ,business.industry ,Macrophages ,Anti-Inflammatory Agents, Non-Steroidal ,Streptozotocin ,medicine.disease ,Rats ,Up-Regulation ,Disease Models, Animal ,Oxidative Stress ,Diabetes Mellitus, Type 1 ,Endocrinology ,Nephrology ,Nephritis, Interstitial ,Female ,Carrier Proteins ,Reactive Oxygen Species ,business ,Oxidative stress ,TXNIP ,medicine.drug - Abstract
BACKGROUND: Diabetic nephropathy is the leading cause of kidney failure in the developed world. Tranilast has been reported to not only act as an anti-inflammatory and anti-fibrotic compound, but it also exerts anti-oxidative stress effects in diabetic nephropathy. Thioredoxin-interacting protein (Txnip) is the endogenous inhibitor of the anti-oxidant thioredoxin and is highly up-regulated in diabetic nephropathy, leading to oxidative stress and fibrosis. In this study, we aimed to investigate whether tranilast exerts its anti-oxidant properties through the inhibition of Txnip. METHODS: Heterozygous Ren-2 rats were rendered diabetic with streptozotocin. Another group of rats were injected with citrate buffer alone and treated as non-diabetic controls. After 6 weeks of diabetes, diabetic rats were divided into two groups: one group gavaged with tranilast at 200 mg/kg/day and another group with vehicle. RESULTS: Diabetic rats had a significant increase in albuminuria, tubulointerstitial fibrosis, peritubular collagen IV accumulation, reactive oxygen species (ROS) and macrophage infiltration (all P < 0.05). These changes were associated with an increase in Txnip mRNA and protein expression in the tubules and glomeruli of diabetic kidney. Treatment with tranilast for 4 weeks significantly attenuated Txnip up-regulation in diabetic rats and this was associated with a reduction in ROS, fibrosis and macrophage infiltration (all P < 0.05). CONCLUSIONS: This is the first study to demonstrate that tranilast not only has anti-inflammatory and anti-fibrotic effects as previously reported but also attenuates the up-regulation of Txnip and oxidative stress in diabetic nephropathy.
- Published
- 2010
16. Transcription Factors Krüppel-Like Factor 6 and Peroxisome Proliferator-Activated Receptor-γ Mediate High Glucose-Induced Thioredoxin-Interacting Protein
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Darren J. Kelly, Christina Y.R. Tan, Carol A. Pollock, Xin-Ming Chen, Weier Qi, and John Holian
- Subjects
Male ,Thioredoxin-Interacting Protein ,Kruppel-Like Transcription Factors ,Peroxisome proliferator-activated receptor ,Cell Cycle Proteins ,Biology ,Cell Line ,Diabetes Mellitus, Experimental ,Pathology and Forensic Medicine ,Rats, Sprague-Dawley ,Proto-Oncogene Proteins ,Gene expression ,Kruppel-Like Factor 6 ,Animals ,Humans ,Gene silencing ,Diabetic Nephropathies ,RNA, Small Interfering ,Promoter Regions, Genetic ,Transcription factor ,Regulation of gene expression ,chemistry.chemical_classification ,Rats ,PPAR gamma ,Disease Models, Animal ,Glucose ,Gene Expression Regulation ,chemistry ,Cancer research ,Signal transduction ,Carrier Proteins ,TXNIP ,Regular Articles - Abstract
We demonstrated recently that thioredoxin-interacting protein (Txnip) and the transcription factor Krüppel-like factor 6 (KLF6) were up-regulated in both in vivo and in vitro models of diabetic nephropathy, thus promoting renal injury. Conversely, peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists have been shown to be renoprotective. Hence, this study was undertaken to determine whether Txnip expression is regulated by the transcription factors KLF6 and PPAR-gamma. By using siRNAs and overexpressing constructs, the role of KLF6 and PPAR-gamma in Txnip transcriptional regulation was determined in human kidney proximal tubule cells and in streptozocin-induced diabetes mellitus in Sprague-Dawley rats, in vitro and in vivo models of diabetic nephropathy, respectively. KLF6 overexpression increased Txnip expression and promoter activity, which was inhibited by concurrent exposure to PPAR-gamma agonists. In contrast, reduced expression of KLF6 by siRNA or exposure to PPAR-gamma agonists attenuated high glucose-induced Txnip expression and promoter activity. KLF6-Txnip promoter binding was decreased in KLF6-silenced cells, whereas PPAR-gamma agonists increased PPAR-gamma-Txnip promoter binding. Indeed, silencing of KLF6 increased PPAR-gamma expression, suggesting endogenous regulation of PPAR-gamma expression by KLF6. Moreover, renal KLF6 and Txnip expression increased in rats with diabetes mellitus and was inhibited by PPAR-gamma agonist treatment; however, KLF6 expression did not change in HK-2 cells exposed to PPAR-gamma agonists. Hence, Txnip expression and promoter activity are mediated via divergent effects of KLF6 and PPAR-gamma transcriptional regulation.
- Published
- 2009
17. Expression, Localization, and Function of the Thioredoxin System in Diabetic Nephropathy
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Andrew M. Herzenberg, Darren J. Kelly, Sih Min Tan, Robyn G Langham, Hans-Henrik Parving, Yuan Zhang, Andrew Advani, Renae M. Gow, Kerri Thai, Weier Qi, Carol A. Pollock, Alison J. Cox, Kim A. Connelly, Richard E. Gilbert, and Per K. Christensen
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medicine.medical_specialty ,Thioredoxin-Interacting Protein ,Biology ,Kidney ,Cell Line ,Diabetes Mellitus, Experimental ,Kidney Tubules, Proximal ,Diabetic nephropathy ,Dogs ,Thioredoxins ,Reference Values ,Internal medicine ,medicine ,Animals ,Diabetic Nephropathies ,RNA, Messenger ,Distal convoluted tubule ,Kidney Tubules, Collecting ,Gene knockdown ,General Medicine ,medicine.disease ,Rats ,Basic Research ,Endocrinology ,medicine.anatomical_structure ,Nephrology ,Renal physiology ,Female ,Thioredoxin ,TXNIP - Abstract
Excessive reactive oxygen species play a key role in the pathogenesis of diabetic nephropathy, but to what extent these result from increased generation, impaired antioxidant systems, or both is incompletely understood. Here, we report the expression, localization, and activity of the antioxidant thioredoxin and its endogenous inhibitor thioredoxin interacting protein (TxnIP) in vivo and in vitro. In normal human and rat kidneys, expression of TxnIP mRNA and protein was most abundant in the glomeruli and distal nephron (distal convoluted tubule and collecting ducts). In contrast, thioredoxin mRNA and protein localized to the renal cortex, particularly within the proximal tubules and to a lesser extent in the distal nephron. Induction of diabetes in rats increased expression of TxnIP but not thioredoxin mRNA. Kidneys from patients with diabetic nephropathy had significantly higher levels of TxnIP than control kidneys, but thioredoxin expression did not differ. In vitro, high glucose increased TxnIP expression in mesangial, NRK (proximal tubule), and MDCK (distal tubule/collecting duct) cells, and decreased the expression of thioredoxin in mesangial and MDCK cells. Knockdown of TxnIP with small interference RNA suggested that TxnIP mediates the glucose-induced impairment of thioredoxin activity. Knockdown of TxnIP also abrogated both glucose-induced 3H-proline incorporation (a marker of collagen production) and oxidative stress. Taken together, these findings suggest that impaired thiol reductive capacity contributes to the generation of reactive oxygen species in diabetes in a site- and cell-specific manner.
- Published
- 2009
18. Transforming growth factor-β/connective tissue growth factor axis in the kidney
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Xin-Ming Chen, Carol A. Pollock, Weier Qi, and Philip Poronnik
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medicine.medical_specialty ,medicine.medical_treatment ,Kidney ,Biochemistry ,Transforming Growth Factor beta1 ,Diabetic nephropathy ,Mice ,Fibrosis ,Internal medicine ,medicine ,Renal fibrosis ,Animals ,Humans ,Extracellular Matrix Proteins ,integumentary system ,biology ,business.industry ,Growth factor ,Connective Tissue Growth Factor ,Kidney metabolism ,Cell Biology ,Transforming growth factor beta ,medicine.disease ,Smad Proteins, Receptor-Regulated ,Rats ,CTGF ,Endocrinology ,medicine.anatomical_structure ,Models, Animal ,Cancer research ,biology.protein ,Kidney Diseases ,business ,Signal Transduction - Abstract
Transforming growth factor-beta(1) (TGFbeta(1)) is recognized as both a fibrogenic and inflammatory cytokine and plays a critical role in the kidney pathophysiology. The dysregulation of TGFbeta(1) has been linked with the development of diabetic nephropathy. Connective tissue growth factor (CTGF) is a fibrogenic cytokine and is recognized as a downstream mediator of TGFbeta(1) in kidney fibrosis. TGFbeta(1) is involved in immunomodulation and fibrosis in the kidney. However, CTGF plays a more specific role in the fibrogenic pathways in the kidney proximal tubule cells. Moreover, CTGF facilitates TGFbeta(1) signaling and promotes renal fibrosis. This suggests CTGF could be a potential target for kidney fibrosis. Long-term inhibition and targeting TGFbeta(1) directly is problematic, therefore, a more fruitful direction targeting diabetic nephropathy may involve the development of therapeutic strategies specifically targeting CTGF.
- Published
- 2008
19. High Glucose-Induced Thioredoxin-Interacting Protein in Renal Proximal Tubule Cells Is Independent of Transforming Growth Factor-β1
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Xin-Ming Chen, Mark Waltham, Weier Qi, Maria Schache, Richard E. Gilbert, Darren J. Kelly, Carol A. Pollock, and Yuan Zhang
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medicine.medical_specialty ,Small interfering RNA ,Thioredoxin-Interacting Protein ,Molecular Sequence Data ,Biology ,Cell Line ,Diabetes Mellitus, Experimental ,Pathology and Forensic Medicine ,Kidney Tubules, Proximal ,Transforming Growth Factor beta1 ,Thioredoxins ,Internal medicine ,Heat shock protein ,Gene expression ,medicine ,Animals ,Humans ,HSP70 Heat-Shock Proteins ,HSP90 Heat-Shock Proteins ,Promoter Regions, Genetic ,TGF beta 1 ,Oligonucleotide Array Sequence Analysis ,Chemokine CCL20 ,Microarray analysis techniques ,Gene Expression Profiling ,Rats, Inbred Strains ,Macrophage Inflammatory Proteins ,Molecular biology ,Rats ,Gene expression profiling ,Glucose ,Endocrinology ,Hyperglycemia ,biology.protein ,Female ,Carrier Proteins ,Reactive Oxygen Species ,TXNIP ,Regular Articles - Abstract
Hyperglycemia is a causative factor in the pathogenesis of diabetic nephropathy. Here, we demonstrate the transcriptional profiles of the human proximal tubule cell line (HK-2 cells) exposed to high glucose using cDNA microarray analysis. Thioredoxin-interacting protein (Txnip) was the gene most significantly increased among 10 strongly up-regulated and 15 down-regulated genes. Txnip, heat shock proteins 70 and 90, chemokine (C-C motif) ligand 20, and matrix metalloproteinase-7 were chosen for verification of gene expression. Real-time reverse transcriptase-polymerase chain reaction confirmed the mRNA expression levels of these five genes, consistent with microarray analysis. The increased protein expression of Txnip, CCL20, and MMP7 were also verified by Western blotting and enzyme-linked immunosorbent assay. Increased expression of Txnip and of nitrotyrosine, as a marker of oxidative stress, were confirmed in vivo in diabetic Ren-2 rats. Subsequent studies focused on the dependence of Txnip expression on up-regulation of transforming growth factor (TGF)-beta1 under high-glucose conditions. Overexpression of Txnip and up-regulation of Txnip promoter activity were observed in cells in which the TGF-beta1 gene was silenced in HK-2 cells using short interfering RNA technology. High glucose further increased both Txnip expression and its promoter activity in TGF-beta1 silenced cells compared with wild-type cells exposed to high glucose, suggesting that high glucose induced Txnip through a TGF-beta1-indepen-dent pathway.
- Published
- 2007
20. The differential regulation of Smad7 in kidney tubule cells by connective tissue growth factor and transforming growth factor-beta1
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Carol A. Pollock, Stephen M. Twigg, Xin-Ming Chen, Darren J. Kelly, Weier Qi, Yuan Zhang, and Richard E. Gilbert
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medicine.medical_specialty ,medicine.medical_treatment ,Connective tissue ,Enzyme-Linked Immunosorbent Assay ,SMAD ,Biology ,Immediate early protein ,Cell Line ,Immediate-Early Proteins ,Smad7 Protein ,Transforming Growth Factor beta1 ,Internal medicine ,medicine ,Animals ,Humans ,DNA Primers ,Analysis of Variance ,integumentary system ,Reverse Transcriptase Polymerase Chain Reaction ,Growth factor ,Connective Tissue Growth Factor ,General Medicine ,Transfection ,Immunohistochemistry ,Rats ,CTGF ,Kidney Tubules ,Endocrinology ,medicine.anatomical_structure ,Gene Expression Regulation ,Nephrology ,Cell culture ,Intercellular Signaling Peptides and Proteins ,RNA Interference ,Signal Transduction ,Transforming growth factor - Abstract
AIMS: Smad7 is an inhibitory Smad that regulates transforming growth factor-beta (TGF-beta) signaling. Connective tissue growth factor (CTGF) is recognized as a potent downstream mediator of the fibrogenic effects of TGF-beta1. SMAD binding sites have been identified in both TGF-beta and CTGF promoters. The effect of CTGF on Smad7 expression and its role in the regulation of Smad7 induced by TGF-beta1 in renal tubular cells is unknown. METHODS: Human model of proximal tubular cells (HK-2 cells) was used and confirmed using a diabetic rat model. RT-PCR was performed to measure Smad7, TGF-beta1 and Smad2 and ELISA was performed to measure active TGF-beta1. CTGF or TGF-beta1 was silenced in HK-2 cells using siRNA methodology. RESULTS: TGF-beta1 induced Smad7 in a time-dependent manner, peaking at 30 min (P
- Published
- 2007
21. PKCδ inhibition normalizes the wound-healing capacity of diabetic human fibroblasts
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Yasutaka Maeda, Amy J. Wagers, Hillary A. Keenan, Chenyu Huang, George L. King, Thomas Thomou, Qian Li, Dennis P. Orgill, Weier Qi, Danielle Eschuk, Kyoungmin Park, Aris Veves, Mogher Khamaisi, Sayaka Katagiri, and Ana Tellechea
- Subjects
0301 basic medicine ,Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,medicine.medical_treatment ,Mice, Nude ,03 medical and health sciences ,0302 clinical medicine ,Cell Movement ,Internal medicine ,medicine ,Poor wound healing ,Animals ,Humans ,Insulin ,Fibroblast ,Protein Kinase Inhibitors ,Protein kinase C ,Cells, Cultured ,Aged ,Cell Proliferation ,Aged, 80 and over ,Gene knockdown ,Wound Healing ,biology ,General Medicine ,Fibroblasts ,Middle Aged ,Cell Hypoxia ,Diabetic Foot ,Insulin receptor ,Vascular endothelial growth factor A ,Protein Kinase C-delta ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,Diabetes Mellitus, Type 1 ,030220 oncology & carcinogenesis ,Gene Knockdown Techniques ,biology.protein ,Female ,Wound healing ,Half-Life ,Research Article - Abstract
Abnormal fibroblast function underlies poor wound healing in patients with diabetes; however, the mechanisms that impair wound healing are poorly defined. Here, we evaluated fibroblasts from individuals who had type 1 diabetes (T1D) for 50 years or more (Medalists, n = 26) and from age-matched controls (n = 7). Compared with those from controls, Medalist fibroblasts demonstrated a reduced migration response to insulin, lower VEGF expression, and less phosphorylated AKT (p-AKT), but not p-ERK, activation. Medalist fibroblasts were also functionally less effective at wound closure in nude mice. Activation of the δ isoform of protein kinase C (PKCδ) was increased in postmortem fibroblasts from Medalists, fibroblasts from living T1D subjects, biopsies of active wounds of living T1D subjects, and granulation tissues from mice with streptozotocin-induced diabetes. Diabetes-induced PKCD mRNA expression was related to a 2-fold increase in the mRNA half-life. Pharmacologic inhibition and siRNA-mediated knockdown of PKCδ or expression of a dominant-negative isoform restored insulin signaling of p-AKT and VEGF expression in vitro and improved wound healing in vivo. Additionally, increasing PKCδ expression in control fibroblasts produced the same abnormalities as those seen in Medalist fibroblasts. Our results indicate that persistent PKCδ elevation in fibroblasts from diabetic patients inhibits insulin signaling and function to impair wound healing and suggest PKCδ inhibition as a potential therapy to improve wound healing in diabetic patients.
- Published
- 2015
22. Transforming growth factor-β1differentially mediates fibronectin and inflammatory cytokine expression in kidney tubular cells
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Xin-Ming Chen, John Holian, Carol A. Pollock, Ellein Mreich, Richard E. Gilbert, Stephen M. Twigg, and Weier Qi
- Subjects
Chemokine ,Physiology ,medicine.medical_treatment ,Smad2 Protein ,Biology ,Kidney Tubules, Proximal ,Transforming Growth Factor beta1 ,Transforming Growth Factor beta2 ,Transforming Growth Factor beta3 ,Transforming Growth Factor beta ,medicine ,Humans ,RNA, Messenger ,RNA, Small Interfering ,Chemokine CCL2 ,Cell Line, Transformed ,Kidney ,Interleukin-8 ,NF-kappa B ,RNA ,FNDC5 ,Fibronectins ,Cell biology ,Transcription Factor AP-1 ,Fibronectin ,Cytokine ,medicine.anatomical_structure ,Cell culture ,biology.protein ,Transforming growth factor - Abstract
Transforming growth factor-β1(TGF-β1) is not only an important fibrogenic but also immunomodulatory cytokine in the human kidney. We have recently demonstrated that TGF-β1induces interleukin-8 (IL-8), macrophage chemoattractant protein-1 (MCP-1), and fibronectin production in renal proximal tubular (HK-2) cells. However, the unique dependence of IL-8, MCP-1, and fibronectin on TGF-β1expression is unknown. The TGF-β1gene was effectively silenced in HK-2 cells using small-interference (si) RNA. Basal secretion of IL-8 and MCP-1 decreased (both P < 0.05) but, paradoxically, fibronectin increased ( P < 0.05) in TGF-β1-silenced cells compared with cells transfected with nonspecific siRNA. Significant increases were observed in mRNA for the TGF-β2( P < 0.05), TGF-β3( P < 0.05) isoforms and pSmad2 ( P < 0.05), which were reflected in protein expression. Concurrent exposure to pan-specific TGF-β antibody reversed the observed increase in fibronectin expression, suggesting that TGF-β2and TGF-β3isoforms mediate the increased fibronectin expression in TGF-β1-silenced cells. An increase in the DNA binding activity of activator protein-1 (AP-1; P < 0.05) was also observed in TGF-β1-silenced cells. In contrast, nuclear factor-κB (NF-κB) DNA binding activity was significantly decreased ( P < 0.0005). These studies demonstrate that TGF-β1is a key regulator of IL-8 and MCP-1, whereas fibronectin expression is regulated by a complex interaction between the TGF-β isoforms in the HK-2 proximal tubular cell line. Decreased expression of TGF-β1reduces chemokine production in association with reduced NF-κB DNA binding activity, suggesting that immunomodulatory pathways in the kidney are specifically dependent on TGF-β1. Conversely, decreased expression of TGF-β1results in increased TGF-β2, TGF-β3, AP-1, and pSmad2 that potentially mediates the observed increase in fibronectin.
- Published
- 2006
23. The renal cortical fibroblast in renal tubulointerstitial fibrosis
- Author
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Weier Qi, Xin-Ming Chen, Philip Poronnik, and Carol A. Pollock
- Subjects
Kidney Cortex ,Stromal cell ,Bone Marrow Cells ,Cell Communication ,Biology ,Biochemistry ,Extracellular matrix ,Paracrine signalling ,Fibrosis ,medicine ,Animals ,Humans ,Renal Insufficiency ,Erythropoietin ,Renal stem cell ,Kidney ,Cell Biology ,Fibroblasts ,medicine.disease ,Kidney Tubules ,medicine.anatomical_structure ,Immunology ,Tubulointerstitial fibrosis ,Cancer research ,Stromal Cells ,Myofibroblast - Abstract
Renal cortical fibroblasts have key roles in mediating intercellular communication with neighboring/infiltrating cells and extracellular matrix (ECM) and maintenance of renal tissue architecture. They express a variety of cytokines, chemokines, growth factors and cell adhesion molecules, playing an active role in paracrine and autocrine interactions and regulating both fibrogenesis and the interstitial inflammatory response. They additionally have an endocrine function in the production of epoetin. Tubulointerstitial fibrosis, the common pathological consequence of renal injury, is characterized by the accumulation of extracellular matrix largely due to excessive production in parallel with reduced degradation, and activated fibroblasts characterized by a myofibroblastic phenotype. Fibroblasts in the kidney may derive from resident fibroblasts, from the circulating fibroblast population or from haemopoetic progenitor or stromal cells derived from the bone marrow. Cells exhibiting a myofibroblastic phenotype may derive from these sources and from tubular cells undergoing epithelial to mesenchymal transformation in response to renal injury. The number of interstitial myofibroblasts correlates closely with tubulointerstitial fibrosis and progressive renal failure. Hence inhibiting myofibroblast formation may be an effective strategy in attenuating the development of renal failure in kidney disease of diverse etiology.
- Published
- 2006
24. Characterization of Glycolytic Enzymes and Pyruvate Kinase M2 in Type 1 and 2 Diabetic Nephropathy.
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Gordin, Daniel, Shah, Hetal, Takanori Shinjo, St-Louis, Ronald, Weier Qi, Kyoungmin Park, Paniagua, Samantha M., Pober, David M., I-Hsien Wu, Bahnam, Vanessa, Brissett, Megan J., Tinsley, Liane J., Dreyfuss, Jonathan M., Hui Pan, Yutong Dong, Niewczas, Monika A., Amenta, Peter, Sadowski, Thorsten, Kannt, Aimo, and Keenan, Hillary A.
- Subjects
PYRUVATE kinase ,DIABETIC nephropathies ,TUMOR necrosis factor receptors ,AMYLOID ,TYPE 1 diabetes ,AMYLOID beta-protein precursor ,SODIUM-glucose cotransporters - Abstract
Objective: Elevated glycolytic enzymes in renal glomeruli correlated with preservation of renal function in the Medalist Study, individuals with ≥50 years of type 1 diabetes. Specifically, pyruvate kinase M2 (PKM2) activation protected insulin-deficient diabetic mice from hyperglycemia-induced glomerular pathology. This study aims to extend these findings in a separate cohort of individuals with type 1 and type 2 diabetes and discover new circulatory biomarkers for renal protection through proteomics and metabolomics of Medalists' plasma. We hypothesize that increased glycolytic flux and improved mitochondrial biogenesis will halt the progression of diabetic nephropathy.Research Design and Methods: Immunoblots analyzed selected glycolytic and mitochondrial enzymes in postmortem glomeruli of non-Medalists with type 1 diabetes (n = 15), type 2 diabetes (n = 19), and no diabetes (n = 5). Plasma proteomic (SOMAscan) (n = 180) and metabolomic screens (n = 214) of Medalists with and without stage 3b chronic kidney disease (CKD) were conducted and significant markers validated by ELISA.Results: Glycolytic (PKM1, PKM2, and ENO1) and mitochondrial (MTCO2) enzymes were significantly elevated in glomeruli of CKD- versus CKD+ individuals with type 2 diabetes. Medalists' plasma PKM2 correlated with estimated glomerular filtration rate (r2 = 0.077; P = 0.0002). Several glucose and mitochondrial enzymes in circulation were upregulated with corresponding downregulation of toxic metabolites in CKD-protected Medalists. Amyloid precursor protein was also significantly upregulated, tumor necrosis factor receptors downregulated, and both confirmed by ELISA.Conclusions: Elevation of enzymes involved in the metabolism of intracellular free glucose and its metabolites in renal glomeruli is connected to preserving kidney function in both type 1 and type 2 diabetes. The renal profile of elevated glycolytic enzymes and reduced toxic glucose metabolites is reflected in the circulation, supporting their use as biomarkers for endogenous renal protective factors in people with diabetes. [ABSTRACT FROM AUTHOR]- Published
- 2019
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25. Integrated actions of transforming growth factor-β1 and connective tissue growth factor in renal fibrosis
- Author
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Carol A. Pollock, T. Polhill, Richard E. Gilbert, Weier Qi, X-M Chen, Stephen M. Twigg, and Philip Poronnik
- Subjects
Collagen Type IV ,medicine.medical_specialty ,Physiology ,medicine.medical_treatment ,Gene Expression ,Connective tissue ,Smad2 Protein ,Kidney ,Antibodies ,Immediate-Early Proteins ,Transforming Growth Factor beta1 ,Transforming Growth Factor beta ,Internal medicine ,TGF beta signaling pathway ,medicine ,Humans ,Fibroblast ,Cells, Cultured ,integumentary system ,biology ,Growth factor ,Connective Tissue Growth Factor ,Fibrosis ,Fibronectins ,DNA-Binding Proteins ,Fibronectin ,CTGF ,medicine.anatomical_structure ,Endocrinology ,Trans-Activators ,biology.protein ,Intercellular Signaling Peptides and Proteins ,Kidney Diseases ,Receptors, Transforming Growth Factor beta ,Signal Transduction ,Transforming growth factor - Abstract
Matrix accumulation in the renal tubulointerstitium is predictive of a progressive decline in renal function. Transforming growth factor-β1 (TGF-β1) and, more recently, connective tissue growth factor (CTGF) are recognized to play key roles in mediating the fibrogenic response, independently of the primary renal insult. Further definition of the independent and interrelated effects of CTGF and TGF-β1 is critical for the development of effective antifibrotic strategies. CTGF (20 ng/ml) induced fibronectin and collagen IV secretion in primary cultures of human proximal tubule cells (PTC) and cortical fibroblasts (CF) compared with control values ( P < 0.005 in all cases). This effect was inhibited by neutralizing antibodies to either TGF-β or to the TGF-β type II receptor (TβRII). TGF-β1 induced a greater increase in fibronectin and collagen IV secretion in both PTC ( P < 0.01) and CF ( P < 0.01) compared with that observed with CTGF alone. The combination of TGF-β1 and CTGF was additive in their effects on both PTC and CF fibronectin and collagen IV secretion. TGF-β1 (2 ng/ml) stimulated CTGF mRNA expression within 30 min, which was sustained for up to 24 h, with a consequent increase in CTGF protein ( P < 0.05), whereas CTGF had no effect on TGF-β1 mRNA or protein expression. TGF-β1 (2 ng/ml) induced phosphorylated (p)Smad-2 within 15 min, which was sustained for up to 24 h. CTGF had a delayed effect on increasing pSmad-2 expression, which was evident at 24 h. In conclusion, this study has demonstrated the key dependence of the fibrogenic actions of CTGF on TGF-β. It has further uniquely demonstrated that CTGF requires TGF-β, signaling through the TβRII in both PTCs and CFs, to exert its fibrogenic response in this in vitro model.
- Published
- 2005
26. Human Cortical Fibroblast Responses to High Glucose and Hypoxia
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Christopher J. Jackson, Philip Poronnik, Weier Qi, Michael Field, Barbara Young, and Carol A. Pollock
- Subjects
Cell physiology ,medicine.medical_specialty ,Kidney Cortex ,Physiology ,Cell Count ,Biology ,Matrix metalloproteinase ,Diabetic nephropathy ,Physiology (medical) ,Diabetes mellitus ,Internal medicine ,Plasminogen Activator Inhibitor 1 ,medicine ,Humans ,RNA, Messenger ,Fibroblast ,Cells, Cultured ,Messenger RNA ,Proteins ,Tissue Inhibitor of Metalloproteinases ,General Medicine ,Fibroblasts ,Hypoxia (medical) ,medicine.disease ,Cell Hypoxia ,Matrix Metalloproteinases ,Glucose ,medicine.anatomical_structure ,Endocrinology ,Nephrology ,Cell culture ,medicine.symptom - Abstract
Background/Aims: Approximately 30% of individuals with diabetes mellitus are susceptible to diabetic nephropathy, whereas ischemic injury uniformly induces renal impairment. As matrix accumulation correlates with progressive renal disease we assessed parameters associated with matrix turnover in response to high glucose ± hypoxia in human cortical fibroblasts (CF). Methods: CF were grown to confluence and exposed to media containing 5 or 25 mmol/l D-glucose for 72 h with or without a superimposed hypoxic insult. Results: High glucose increased cellular protein content (p < 0.05). Combined high glucose and hypoxia induced a further increase in cellular protein content (p < 0.005), suggestive of a synergistic hypertrophic effect. MMP secretion corresponded inversely with changes in TIMP expression. In cell cultures derived from 2/3 of patients, high glucose increased MMP-9 (p < 0.0005) and MMP-2 (p < 0.005) while TIMP-1 was reduced (p = 0.05). In the remaining cell cultures derived from 1/3 of patients, MMP-2 was reduced (p < 0.0001) while TIMP-1 and TIMP-2 were both increased (p < 0.05). In contrast, hypoxia induced uniform reductions in MMP-9 and MMP-2 in both normal and high glucose conditions. High glucose increased the expression of PAI-1 mRNA (p < 0.05) in all patients independent of changes in the MMP-TIMP axis. Conclusions: In summary, variability was observed in the MMP-TIMP axis following exposure to high glucose. In contrast, high glucose uniformly induces PAI-1 expression. Hypoxic insults uniformly reduce matrix breakdown independent of the prevailing glucose conditions.
- Published
- 2004
27. Contents Vol. 96, 2004
- Author
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Michal Mysliwiec, Shu-Ming Chen, Cheng-Deng Kuo, Jakob Scholbach, Weier Qi, Michael Field, Dariusz Pawlak, Krystyna Pawlak, Ingo Dimos, Christopher J. Jackson, Low-Tone Ho, Barbara Young, Carol A. Pollock, Jyh-Fei Liao, Thomas Scholbach, and Philip Poronnik
- Subjects
Nephrology ,Physiology ,Physiology (medical) ,General Medicine - Published
- 2004
28. Contents Vol. 86, 2000
- Author
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Okan Bakınen, Gilbert Deray, Ken Okumura, Keiko Uchida, Ljubica Ðukanović, J.H. Park, Y.S. Haviv, Mitsuyoshi Furuhashi, Shou-Shan Chiang, Vladisav Stefanovic, Martin Ellbogen, E. Sedano, L. Grcevska, Sun Ae Yoon, Yuet-Ching Tay, Junne-Ming Sung, Hirotsugu Iwatani, Matt Koch, Toshiyuki Imasawa, Michael Field, Masahiko Nakamoto, Vincenzo Bellizzi, Jung-Kuei Pai, H. Pasantes-Morales, Yoshiyuki Hiki, Robert Dunlay, Yoshiaki Takemoto, Hideaki Yamabe, Johan W. de Fijter, Yutaka Kobayashi, Junko Tanaka, Ayşegül Örs Zümrütdal, Jyh-Gang Leu, B.K. Bang, Katsuo Suyama, Shigetake Sasayama, J. Möcks, A. Rodríguez-Cuartero, Toshika Okumiya, Minako Koike, Byung Kee Bang, Naoyuki Tamura, Hacı Veli Atalay, Adriaan M. Kamper, I. Villen, Chie Tomida, Heather J. Saunders, Kenji Tsuchida, Akira Kawashima, Giuseppe La Greca, Ming-Cheng Wang, Shu-May Lin, Tetuhiko Yoshida, Qu Huiqi, Yukitaka Maruyama, Hiroshi Nihei, Michihiro Gotoh, Kazuho Honda, Yasukazu Yamada, Shinichi Kakumu, Sohji Nagase, Elsie-C. Chan, Mutsuko Hidaka, Atsushi Ueda, Aysun Karabay Bayazit, Kazumasa Aoyagi, Masaya Yamato, Akio Koyama, Yoshihiro Matsumoto, Diana Ionova, Wei-Chi Lee, Slavenka Janković, Hiroshi Osawa, Tatsuo Hosoya, Qiu Mingcai, Takako Takita, Lin Shan, Shu-Yin Kuo, Gopala K. Rangan, Tsung Hsiu Wang, Richard J. Lund, Tatsuya Nakatani, Harutaka Yamada, Krasimira Sepetlieva, M. Pérez-Suarez, Jerome G. Porush, Aytül Noyan, Stefan Fründ, Predrag Vlahović, Weier Qi, P A Conz, Akihiko Kato, Hui Kyung Jeon, Jelena Marinkovic, Kazuhiro Okano, Akira Hishida, J.Y. Choi, Krystyna Szprynger, Brad Oldemeyer, Satoru Tsunoda, Takayuki Fujita, Hatice Bodur, G. Petruševska, Isao Ohsawa, Danuta Zwolińska, York Leng Yu, Arao Futenma, Hitoe Suzuki, G. Maschio, J.L. Pérez-Castrillón, Rich Jones, Gakusen Nishihara, Takanari Aoki, Maria Szczepańska, Danica Bukvić, Sumio Tateno, Masahiro Kakihara, M. Milovanceva-Popovska, Young Ok Kim, Kuddusi Cengiz, M. Arrabal-Martín, Yau-Huei Wei, Tein-Chung Lu, Toshiyuki Takahashi, David A. Vesey, Hiroshi Tatsumi, Kamen Tcachev, Keisuke Yamamoto, Eriya Kikawada, Monika Bulla, Vincenzo Terracciano, Jeng-Jong Huang, Haruo Tomonari, Junji Terao, Halil Uçan, Atsushi Fukatsu, Atsushi Yamauchi, Sun Jeong Lim, Robert Kleta, Kosaku Nitta, Atsushi Satomura, A. Zuluaga, Yoshiko Baba, Morito Endo, F.J. Pérez-Blanco, Hassan Izzedine, Paik-Seong Lim, M. Polenakovic, Mitsuaki Kaizuka, C.W. Yang, Takashi Uzu, A. Egon van der Bijl, Biagio Di Iorio, Chikao Yasunaga, Fumiko Tateyama, Aya Abe, Yiping Wang, Eun Jung Jun, Chan Joo Kim, Chang Hee Han, Ali Anarat, Eri Muso, Satoru Kuriyama, Izumi Amano, Aki Hirayama, Takanobu Sakemi, Y.M. Choo, Wey-Wen Jiang, G.B. Kim, Fen-Fen Chen, S. Morales Mulia, Anna Medyńska, Marina Mitić-Zlatković, Wako Yumura, I. Justo-Muradas, Carlo Crepaldi, Koichi Suzuki, Yasuhiro Chikamori, Kenichi Shirato, Naoto Miura, Y.S. Kim, Katsumi Takemura, Leendert C. Paul, Carol A. Pollock, A.J. Meares, Masatomo Yashiro, Vincent Launay-Vacher, Hiroyuki Ohi, David W. Johnson, E. Saracibar, David Harris, and Eberhard Kuwertz-Bröking
- Subjects
Traditional medicine ,business.industry ,Medicine ,business - Published
- 2000
29. Enalaprilat Directly Ameliorates in vitro Cyclosporin Nephrotoxicity in Human Tubulo-Interstitial Cells
- Author
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Michael Field, Heather J. Saunders, David A. Vesey, David W. Johnson, Weier Qi, and Carol A. Pollock
- Subjects
medicine.medical_specialty ,Kidney Cortex ,Platelet-derived growth factor ,Enalaprilat ,Cell Survival ,Angiotensin-Converting Enzyme Inhibitors ,Pharmacology ,Nephrotoxicity ,Kidney Tubules, Proximal ,chemistry.chemical_compound ,Internal medicine ,Cyclosporin a ,medicine ,Humans ,Cells, Cultured ,business.industry ,Angiotensin II ,Fibroblasts ,Ciclosporin ,In vitro ,Endocrinology ,chemistry ,Culture Media, Conditioned ,ACE inhibitor ,Cyclosporine ,Cytokines ,Nephritis, Interstitial ,Collagen ,business ,Cell Division ,Immunosuppressive Agents ,medicine.drug - Abstract
Background/Aims: Several recent studies have suggested that angiotensin-converting enzyme (ACE) inhibitors ameliorate chronic cyclosporin A (CyA) tubulo-interstitial disease by mechanisms independent of their antihypertensive effects. The aim of the present study was to determine whether ACE inhibition exerts a direct beneficial effect on the tubulo-interstitium in an in vitro model of chronic CyA nephropathy. Methods: Primary cultures of human proximal tubular cells (PTC) and renal cortical fibroblasts (CF) were exposed for 24 h to CyA in the presence or absence of enalaprilat. Parameters of tubulo-interstitial nephrotoxicity were then measured including collagen synthesis (proline incorporation), tubular viability and function (thymidine incorporation, lactate dehydrogenase release, and apical sodium-hydrogen exchange), and secretion of insulin-like growth factor I, transforming growth factor beta 1 (TGFβ1), and platelet-derived growth factor. Results: CyA promoted CF collagen synthesis, PTC cytotoxicity (suppressed viability, growth and sodium transport), and tubulo-interstitial fibrogenic cytokine release (CF secretion of insulin-like growth factor I and PTC secretion of TGFβ1 and platelet-derived growth factor). Enalaprilat completely reversed the stimulatory effects of CyA on CF collagen synthesis (CyA + enalaprilat 6.40 ± 0.50% vs. CyA alone 8.33 ± 0.56% vs. control 6.57 ± 0.62% vs. enalaprilat alone 5.55 ± 0.93%, p < 0.05) and PTC secretion of TGFβ1 (0.71 ± 0.11, 1.13 ± 0.09, 0.89 ± 0.07, and 0.67 ± 0.09 ng/mg protein/day, respectively, p < 0.05). However, the other manifestations of CyA toxicity were not significantly reversed by concomitant enalaprilat administration. Conclusions: ACE inhibition directly prevents CyA-induced interstitial fibrosis, but not proximal tubule cytotoxicity, independently of haemodynamic and systemic renin-angiotensin system effects. Renoprotection may be partially afforded by directly preventing the tubular secretion of TGFβ1.
- Published
- 2000
30. Induction of vascular insulin resistance and endothelin-1 expression and acceleration of atherosclerosis by the overexpression of protein kinase C-β isoform in the endothelium
- Author
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George L. King, Kyoungmin Park, Qian Li, Christian Rask-Madsen, Weier Qi, Chenzhong Li, Koji Mizutani, Paul L. Huang, and Akira Mima
- Subjects
Apolipoprotein E ,Male ,medicine.medical_specialty ,Endothelium ,Nitric Oxide Synthase Type III ,Physiology ,Vascular Cell Adhesion Molecule-1 ,Biology ,Article ,Mice ,Insulin resistance ,Apolipoproteins E ,Internal medicine ,Protein Kinase C beta ,medicine ,Animals ,Endothelial dysfunction ,Protein kinase B ,Aorta ,Mice, Knockout ,Endothelin-1 ,medicine.disease ,Atherosclerosis ,Endothelin 1 ,Up-Regulation ,Endothelial stem cell ,Isoenzymes ,Insulin receptor ,Disease Models, Animal ,medicine.anatomical_structure ,Endocrinology ,biology.protein ,Female ,Endothelium, Vascular ,Insulin Resistance ,Cardiology and Cardiovascular Medicine ,Proto-Oncogene Proteins c-akt - Abstract
Rationale: Loss of insulin action in the endothelium can cause endothelial dysfunction and atherosclerosis. Hyperglycemia and elevated fatty acids induced by diabetes mellitus can activate protein kinase C-β isoforms and selectively inhibit insulin signaling via phosphatidylinositol 3-kinase/Akt pathway to inhibit the activation of endothelial nitric oxide synthase and metabolic actions. Objective: To demonstrate that overexpressing protein kinase C-β2 isoform in endothelial cells can cause selective insulin resistance and exacerbate atherosclerosis in the aorta. Methods and Results: Protein kinase C-β2 isoform was overexpressed in endothelial cells using a promoter of vascular endothelial cell cadherin. These mice were cross-bred with apoE −/− mice [Tg (Prkcb) apoE −/− ]. On a Western diet, Tg(Prkcb) apoE −/− and apoE −/− mice did not differ in systemic insulin sensitivity, glucose tolerance, plasma lipid, or blood pressure. Insulin action in endothelial cells and femoral artery from Tg(Prkcb) apoE −/− mice was impaired by ≈40% with respect to Akt/endothelial nitric oxide synthase activation, and leukocyte-endothelial cell binding increased in cultured lung endothelial cells from Tg(Prkcb) apoE −/− mice compared with that from apoE −/− mice. Basal and angiotensin-stimulated big endothelin-1 levels were elevated in Tg(Prkcb) apoE −/− mice compared with apoE −/− mice. The severity of atherosclerosis in the aorta from Tg(Prkcb) apoE −/− mice increased by ≈70% as measured by en face fat staining and plaque content of the number of smooth muscle cells, macrophages, and extracellular matrix. Conclusions: Specific protein kinase C-β2 activation in the endothelial cells caused dysfunction and accelerated atherosclerosis because of loss of insulin-stimulated Akt/endothelial nitric oxide synthase activation and angiotensin-induced increases in endothelin-1 expression.
- Published
- 2013
31. Retinal not systemic oxidative and inflammatory stress correlated with VEGF expression in rodent models of insulin resistance and diabetes
- Author
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Kyoungmin Park, Munehiro Kitada, Steven E. Shoelson, Christian Jobin, Edward Yu, Motonobu Matsumoto, George L. King, Akira Mima, Koji Mizutani, Junko Hiraoka-Yamomoto, Jongsoon Lee, Christian Rask-Madsen, Qian Li, Weier Qi, and Takeshi Shimada
- Subjects
Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Inflammation ,Enzyme-Linked Immunosorbent Assay ,Biology ,medicine.disease_cause ,Retina ,Diabetes Mellitus, Experimental ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Mice ,Insulin resistance ,Stress, Physiological ,Internal medicine ,Diabetes mellitus ,Malondialdehyde ,medicine ,Animals ,Obesity ,RNA, Messenger ,skin and connective tissue diseases ,CD11b Antigen ,Diabetic Retinopathy ,Reverse Transcriptase Polymerase Chain Reaction ,NF-kappa B ,Deoxyguanosine ,Retinal ,Diabetic retinopathy ,Articles ,medicine.disease ,CD11c Antigen ,Rats ,Rats, Zucker ,Mice, Inbred C57BL ,Vascular endothelial growth factor A ,Oxidative Stress ,Endocrinology ,C-Reactive Protein ,chemistry ,8-Hydroxy-2'-Deoxyguanosine ,sense organs ,medicine.symptom ,Insulin Resistance ,Oxidative stress ,Biomarkers - Abstract
To correlate changes between VEGF expression with systemic and retinal oxidative stress and inflammation in rodent models of obesity induced insulin resistance and diabetes.Retinal VEGF mRNA and protein levels were assessed by RT-PCR and VEGF ELISA, respectively. Urinary 8-hydroxydeoxyguanosine (8-OHdG), blood levels of C-reactive protein (CRP), malondialdehyde (MDA), and CD11b/c positive cell ratio were used as systemic inflammatory markers. Retinal expression of Nox2, Nox4, and p47phox mRNA levels were measured as oxidative stress markers. TNF-α, inter-cellular adhesion molecule-1 (ICAM-1), IL1β, and activation of nuclear factor κB (NF-κB) were used as retinal inflammatory markers.Retinal VEGF mRNA and protein expression increased in Zucker diabetic fatty (ZDF(fa/fa)) rats and streptozotosin (STZ) induced diabetic Sprague-Dawley rats, after two months of disease, but not in Zucker fatty (ZF) rats. Systemic markers of oxidative stress and inflammation were elevated in insulin resistant and diabetic rats. Some oxidative stress and inflammatory markers (TNF-α, IL-6, ICAM-1, and IL1-β) were upregulated in the retina of ZDF(fa/fa) and STZ diabetic rats after 4 months of disease. In contrast, activation of NF-κB in the retina was observed in high fat fed nondiabetic and diabetic cis-NF-κB(EGFP) mice, ZF, ZDF(fa/fa), and STZ-induced diabetic rats.Only persistent hyperglycemia and diabetes increased retinal VEGF expression. Some markers of inflammation and oxidative stress were elevated in the retina and systemic circulation of obese and insulin resistant rodents with and without diabetes. Induction of VEGF and its associated retinal pathologies by diabetes requires chronic hyperglycemia and factors in addition to inflammation and oxidative stress.
- Published
- 2012
32. Glomerular VEGF resistance induced by PKCδ/SHP-1 activation and contribution to diabetic nephropathy
- Author
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Christian Rask-Madsen, Akira Mima, Munehiro Kitada, Michael Leitges, Qian Li, Pedro Geraldes, Motonobu Matsumoto, Koji Mizutani, Chenzhong Li, George L. King, and Weier Qi
- Subjects
Male ,Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,p38 mitogen-activated protein kinases ,Kidney Glomerulus ,Apoptosis ,Biology ,Biochemistry ,p38 Mitogen-Activated Protein Kinases ,Podocyte ,Research Communications ,Diabetic nephropathy ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Mice ,Internal medicine ,Genetics ,medicine ,Animals ,Diabetic Nephropathies ,RNA, Small Interfering ,Molecular Biology ,Cells, Cultured ,Mice, Knockout ,Base Sequence ,Podocytes ,Protein Tyrosine Phosphatase, Non-Receptor Type 6 ,NF-kappa B ,Endothelial Cells ,Kinase insert domain receptor ,medicine.disease ,Vascular Endothelial Growth Factor Receptor-2 ,Rats ,Vascular endothelial growth factor ,Enzyme Activation ,Vascular endothelial growth factor A ,Protein Kinase C-delta ,Endocrinology ,medicine.anatomical_structure ,PRKCD ,Glucose ,chemistry ,Female ,Signal transduction ,Biotechnology ,Signal Transduction - Abstract
This study characterizes the effect of glucose-induced activation of protein kinase Cδ (PKCδ) and Src homology-2 domain-containing phosphatase-1 (SHP-1) expression on vascular endothelial growth factor (VEGF) actions in glomerular podocytes in cultures and in glomeruli of diabetic rodents. Elevation of glucose levels induced PKCδ and p38 mitogen-activated protein kinase (p38 MAPK) to increase SHP-1 expression, increased podocyte apoptosis, and inhibited VEGF activation in podocytes and glomerular endothelial cells. The adverse effects of high glucose levels can be negated by molecular inhibitors of PKCδ, p38MAPK, and SHP-1 and only partially reduced by antioxidants and nuclear factor-κB (NF-κB) inhibitor. Increased PKCδ activation and SHP-1 expression correlated with loss of VEGF signaling and podocyte numbers in the glomeruli of diabetic rats and mice. In contrast, diabetic PKCδ-knockout (Prkcd−/−) mice did not exhibit activation of p38 MAPK and SHP-1 or inhibition of VEGF signaling in renal glomeruli. Functionally, diabetic Prkcd−/− mice had decreased expressions of TGFβ, VEGF, and extracellular matrix and less albuminuria than diabetic Prkcd+/+ mice. Hyperglycemia and diabetes can cause glomerular podocyte apoptosis and endothelial dysfunction partly due to increased PKCδ/p38 MAPK activation and the expression of SHP-1 to cause VEGF resistance, independent of NF-κB activation.—Mima, A., Kitada, M., Geraldes, P., Li, Q., Matsumoto, M., Mizutani, K., Qi, W., Li, C., Leitges, M., Rask-Madsen, C., King, G. L. Glomerular VEGF resistance induced by PKCδ/ SHP-1 activation and contribution to diabetic nephropathy.
- Published
- 2012
33. 3′,4′-Dihydroxyflavonol Antioxidant Attenuates Diastolic Dysfunction and Cardiac Remodeling in Streptozotocin-Induced Diabetic m(Ren2)27 Rats
- Author
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Amanda J. Edgley, Kim A. Connelly, Weier Qi, Owen L. Woodman, Darren J. Kelly, Henry Krum, Fay Lin Khong, and Yuan Zhang
- Subjects
Cardiac function curve ,Male ,medicine.medical_specialty ,Cardiac Catheterization ,Flavonols ,Cardiac fibrosis ,Diabetic Cardiomyopathies ,Science ,Diastole ,medicine.disease_cause ,Cardiovascular ,Antioxidants ,Diabetes Mellitus, Experimental ,Ventricular Dysfunction, Left ,Endocrinology ,Fibrosis ,Diabetic cardiomyopathy ,Internal medicine ,medicine ,Animals ,In Situ Hybridization ,Heart Failure ,Diabetic Endocrinology ,Multidisciplinary ,business.industry ,Homozygote ,NADPH Oxidases ,Diabetes Mellitus Type 1 ,medicine.disease ,Rats ,Oxidative Stress ,Echocardiography ,Heart failure ,Heart catheterization ,Medicine ,Autoradiography ,Rats, Transgenic ,business ,Reactive Oxygen Species ,Oxidative stress ,Research Article - Abstract
BackgroundDiabetic cardiomyopathy (DCM) is an increasingly recognized cause of chronic heart failure amongst diabetic patients. Both increased reactive oxygen species (ROS) generation and impaired ROS scavenging have been implicated in the pathogenesis of hyperglycemia-induced left ventricular dysfunction, cardiac fibrosis, apoptosis and hypertrophy. We hypothesized that 3',4'-dihydroxyflavonol (DiOHF), a small highly lipid soluble synthetic flavonol, may prevent DCM by scavenging ROS, thus preventing ROS-induced cardiac damage.Methodology/principal findingsSix week old homozygous Ren-2 rats were randomized to receive either streptozotocin or citrate buffer, then further randomized to receive either DiOHF (1 mg/kg/day) by oral gavage or vehicle for six weeks. Cardiac function was assessed via echocardiography and left ventricular cardiac catheterization before the animals were sacrificed and hearts removed for histological and molecular analyses. Diabetic Ren-2 rats showed evidence of diastolic dysfunction with prolonged deceleration time, reduced E/A ratio, and increased slope of end-diastolic pressure volume relationship (EDPVR) in association with marked interstitial fibrosis and oxidative stress (all PConclusionsInhibition of ROS production and action by DiOHF improved diastolic function and reduced myocyte hypertrophy as well as collagen deposition. These findings suggest the potential clinical utility of antioxidative compounds such as flavonols in the prevention of diabetes-associated cardiac dysfunction.
- Published
- 2011
34. Ramipril retards development of aortic valve stenosis in a rabbit model: mechanistic considerations
- Author
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Doan Tm, Ngo, Irene, Stafford, Aaron L, Sverdlov, Weier, Qi, Ronald D, Wuttke, Yuan, Zhang, Darren J, Kelly, Helen, Weedon, Malcolm D, Smith, Jennifer A, Kennedy, and John D, Horowitz
- Subjects
Male ,Angiotensin-Converting Enzyme Inhibitors ,Aortic Valve Stenosis ,Vitamins ,Arginine ,Research Papers ,Disease Models, Animal ,Ramipril ,Echocardiography ,Aortic Valve ,Ergocalciferols ,Disease Progression ,Animals ,Humans ,Rabbits ,Enzyme Inhibitors ,Carrier Proteins - Abstract
Aortic valve stenosis (AVS) is associated with significant cardiovascular morbidity and mortality. To date, no therapeutic modality has been shown to be effective in retarding AVS progression. We evaluated the effect of angiotensin-converting enzyme inhibition with ramipril on disease progression in a recently developed rabbit model of AVS.The effects of 8 weeks of treatment with either vitamin D₂ at 25,000 IU for 4 days a week alone or in combination with ramipril (0.5 mg·kg⁻¹) on aortic valve structure and function were examined in New Zealand white rabbits. Echocardiographic aortic valve backscatter (AV(BS)) and aortic valve:outflow tract flow velocity ratio were utilized to quantify changes in valve structure and function.Treatment with ramipril significantly reduced AV(BS) and improved aortic valve :outflow tract flow velocity ratio. The intravalvular content of the pro-oxidant thioredoxin-interacting protein was decreased significantly with ramipril treatment. Endothelial function, as measured by asymmetric dimethylarginine concentrations and vascular responses to ACh, was improved significantly with ramipril treatment.Ramipril retards the development of AVS, reduces valvular thioredoxin-interacting protein accumulation and limits endothelial dysfunction in this animal model. These findings provide important insights into the mechanisms of AVS development and an impetus for future human studies of AVS retardation using an angiotensin-converting enzyme inhibitor.
- Published
- 2010
35. Thioredoxin-Interacting Protein: A Potential Therapeutic Target for Treatment of Progressive Fibrosis in Diabetic Nephropathy
- Author
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Tan, Christina Y.R., primary, Weier, Qi, additional, Zhang, Yuan, additional, Cox, Alison J., additional, Kelly, Darren J., additional, and Langham, Robyn G., additional
- Published
- 2015
- Full Text
- View/download PDF
36. CTGF and chronic kidney fibrosis
- Author
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Xin-Ming Chen, Carol A. Pollock, and Weier Qi
- Subjects
Kidney ,General Immunology and Microbiology ,biology ,business.industry ,Connective Tissue Growth Factor ,medicine.disease ,Angiotensin II ,Fibrosis ,General Biochemistry, Genetics and Molecular Biology ,Diabetic nephropathy ,CTGF ,Extracellular matrix ,medicine.anatomical_structure ,Chronic Disease ,medicine ,biology.protein ,Cancer research ,Renal fibrosis ,Humans ,Kidney Diseases ,business ,TGF beta 1 ,Signal Transduction - Abstract
Chronic kidney fibrosis is the unifying pathological feature of diverse renal disease leading to a progressive decline in renal function and eventually end-stage kidney failure. Many growth factors are able to induce an imbalance of extracellular matrix production and degradation, leading to excessive matrix and fibrosis in both glomeruli and in the tubulointerstitium. Over the last decade the role of connective tissue growth factor (CTGF) in renal fibrosis has been intensively studied. CTGF participates in cell proliferation, migration, and differentiation and mediates profibrotic activity by acting either directly, or as a co-factor for TGF beta 1, which is well characterised as a key cytokine mediating both the induction and promotion of fibrogenesis. CTGF also has the potential to modulate factors such as VEGF and bone morphogenic proteins, which are integral to both the development and repair process inherent in renal fibrogenesis. This review focuses on the role of CTGF in renal fibrosis and specifically its role in inducing fibrosis by factors integrally involved in the development of diabetic nephropathy, namely high glucose, angiotensin II, TGF beta 1 and AGEs.
- Published
- 2009
37. Isolation and primary culture of human proximal tubule cells
- Author
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David A, Vesey, Weier, Qi, Xinming, Chen, Carol A, Pollock, and David W, Johnson
- Subjects
Kidney Tubules, Proximal ,Cell Culture Techniques ,Humans ,Epithelial Cells ,Cells, Cultured - Abstract
Primary cultures of renal proximal tubule cells (PTC) have been widely used to investigate tubule cell function. They provide a model system where confounding influences of renal haemodynamics, cell heterogeneity, and neural activity are eliminated. Additionally they are likely to more closely resemble PTC in vivo than established kidney cell lines, which are often virally immortalised and are of uncertain origin. This chapter describes a method used in our laboratories to isolate and culture pure populations of human PTC. The cortex is dissected away from the medulla and minced finely. Following collagenase digestion, the cells are passed through a sieve and separated on a Percoll density gradient. An almost pure population of tubule fragments form a band at the base of the gradient. Cultured in a hormonally defined serum-free growth media, they form a tightly packed monolayer that retains the differentiated characteristics of PTC for up to three passages.
- Published
- 2009
38. Isolation and Primary Culture of Human Proximal Tubule Cells
- Author
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Weier Qi, Carol A. Pollock, David A. Vesey, Xingming Chen, and David W. Johnson
- Subjects
education.field_of_study ,endocrine system diseases ,Chemistry ,Population ,Cell ,Cell biology ,Tubule ,medicine.anatomical_structure ,In vivo ,Cell culture ,Collagenase ,medicine ,education ,Percoll ,Medulla ,medicine.drug - Abstract
Primary cultures of renal proximal tubule cells (PTC) have been widely used to investigate tubule cell function. They provide a model system where confounding influences of renal haemodynamics, cell heterogeneity, and neural activity are eliminated. Additionally they are likely to more closely resemble PTC in vivo than established kidney cell lines, which are often virally immortalised and are of uncertain origin. This chapter describes a method used in our laboratories to isolate and culture pure populations of human PTC. The cortex is dissected away from the medulla and minced finely. Following collagenase digestion, the cells are passed through a sieve and separated on a Percoll density gradient. An almost pure population of tubule fragments form a band at the base of the gradient. Cultured in a hormonally defined serum-free growth media, they form a tightly packed monolayer that retains the differentiated characteristics of PTC for up to three passages.
- Published
- 2008
39. Role of Kruppel-like factor 6 in transforming growth factor-beta1-induced epithelial-mesenchymal transition of proximal tubule cells
- Author
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John Holian, Carol A. Pollock, Xin-Ming Chen, Yuan Zhang, Weier Qi, Darren J. Kelly, and Ellein Mreich
- Subjects
medicine.medical_specialty ,Physiology ,Cellular differentiation ,Kruppel-Like Transcription Factors ,Gene Expression ,Vimentin ,Biology ,Transfection ,Antibodies ,Diabetes Mellitus, Experimental ,Kidney Tubules, Proximal ,Mesoderm ,Transforming Growth Factor beta1 ,Downregulation and upregulation ,Internal medicine ,Proto-Oncogene Proteins ,medicine ,Kruppel-Like Factor 6 ,Gene silencing ,Animals ,Humans ,Epithelial–mesenchymal transition ,Gene Silencing ,RNA, Small Interfering ,Cell Line, Transformed ,Cell Differentiation ,Epithelial Cells ,Rats, Inbred Strains ,Articles ,Cadherins ,Cell biology ,Rats ,Endocrinology ,KLF6 ,Glucose ,biology.protein ,Female ,Rats, Transgenic ,Transforming growth factor - Abstract
Krüppel-like factor 6 (KLF6) is a DNA-binding protein containing a triple zinc-fingered motif and plays a key role in the regulation of cell proliferation, differentiation, and development. More recently it has been implicated in hepatic fibrosis via its binding to the transforming growth factor (TGF)-β control element. In the kidney, epithelial-mesenchymal transition (EMT) is a major contributor to the pathogenesis of renal fibrosis, with TGF-β1 being a key mediator of EMT. The present study aimed to determine the role of KLF6 and TGF-β1 in EMT in proximal tubule cells. To determine the relevance in clinical disease, KLF6 was measured in kidneys of streptozotocin-induced diabetic Ren-2 rats and in cells exposed to high (30 mM) glucose. TGF-β1 was confirmed to induce EMT by morphological change, loss of E-cadherin, and gain in vimentin expression. KLF6 mRNA expression was concomitantly measured. To determine the role of KLF6 in EMT, the above markers of EMT were determined in KLF6-silenced (small interfering RNA) and KLF6-overexpressing proximal tubule cells. KLF6 overexpression significantly promoted a phenotype consistent with EMT. High glucose induced KLF6 in proximal tubule cells ( P < 0.05). This increase in KLF6 in response to high glucose was TGF-β1 mediated. In an in vivo model of diabetic nephropathy KLF6 increased at week 8 ( P < 0.05). KLF6 plays a permissive role in TGF-β1-induced EMT in proximal tubule cells. Its upregulation in in vivo models of diabetic nephropathy suggests it as a potential therapeutic target.
- Published
- 2008
40. High glucose induces macrophage inflammatory protein-3 alpha in renal proximal tubule cells via a transforming growth factor-beta 1 dependent mechanism
- Author
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Xin-Ming Chen, Weier Qi, John Holian, Richard E. Gilbert, Ellein Mreich, Carol A. Pollock, Darren J. Kelly, and Yuan Zhang
- Subjects
medicine.medical_specialty ,Chemokine ,Small interfering RNA ,CD3 ,Inflammation ,Cell Line ,Diabetes Mellitus, Experimental ,Kidney Tubules, Proximal ,Transforming Growth Factor beta1 ,Internal medicine ,Gene expression ,medicine ,Animals ,Humans ,Diabetic Nephropathies ,RNA, Messenger ,Macrophage inflammatory protein ,DNA Primers ,Transplantation ,Chemokine CCL20 ,biology ,Reverse Transcriptase Polymerase Chain Reaction ,Transforming growth factor beta ,Immunohistochemistry ,Rats ,CCL20 ,Endocrinology ,Glucose ,Nephrology ,biology.protein ,Female ,medicine.symptom - Abstract
Hyperglycaemia is a causative factor in the pathogenesis of diabetic nephropathy, known to induce chemokines in the kidney. Macrophage inflammatory protein-3 alpha (MIP-3 alpha) is a CC chemokine that has been reported to attract memory T lymphocytes. Our previous microarray study showed significant increased level of MIP-3 alpha in high glucose-induced transcriptional profile in renal proximal tubule cells. Transforming growth factor-beta1 (TGF-beta1) is a key regulator in inflammation and fibrosis in diabetes mellitus setting.This study aimed to determine the role of TGF beta 1 in high glucose-induced MIP-3 alpha expression. An in vitro model of human proximal tubular cells (HK-2 cells) and an in vivo model of the transgenic (mRen-2)27 diabetic rat, well characterized as a model of human diabetic nephropathy, were used. Small interfering RNA technology was used to silence TGF-beta1 gene in HK-2 cells and subsequent experiments were performed to measure mRNA and protein levels of MIP-3 alpha using real time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Immunohistochemistry was used to measure the protein level of MIP-3 alpha and CD3 a marker of T lymphocytes in the in vivo model.MIP-3 alpha mRNA and protein expression was increased in HK-2 cells by high glucose and TGF-beta1. MIP-3 alpha was up-regulated in the dilated tubules of diabetic rats compared with non-diabetic control animals and CD3 was found to be present around the dilated tubules expressing MIP-3 alpha. This up-regulation was attenuated in the presence of an angiotensin-converting enzyme (ACE) inhibitor. MIP-3 alpha expression significantly decreased in cells in which the TGF-beta1 gene was silenced using small interfering RNA. Furthermore, exposure to high glucose did not induce MIP-3 alpha expression in TGF-beta1 gene silenced cells compared with wild-type cells.In summary, we have uniquely demonstrated that high glucose increases MIP-3 alpha through a TGF beta 1 dependent pathway, suggesting the centrality of TGF-beta1 in both the inflammatory and previously demonstrated fibrotic responses in diabetic nephropathy.
- Published
- 2007
41. Increased renal gene transcription of protein kinase C-beta in human diabetic nephropathy: relationship to long-term glycaemic control
- Author
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Robyn G Langham, Alison J. Cox, Kerri Thai, Weier Qi, Renae M. Gow, Carol A. Pollock, Per K. Christensen, Darren J. Kelly, Richard E. Gilbert, Yuan Zhang, and Hans-Henrik Parving
- Subjects
Gene isoform ,Blood Glucose ,Male ,medicine.medical_specialty ,DNA, Complementary ,Protein Kinase C-alpha ,Transcription, Genetic ,Endocrinology, Diabetes and Metabolism ,Biopsy ,Protein Kinase C beta ,PKC alpha ,Kidney ,Gene Expression Regulation, Enzymologic ,Pathogenesis ,Diabetic nephropathy ,Mediator ,Reference Values ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,Medicine ,Humans ,Diabetic Nephropathies ,Protein kinase C ,Protein Kinase C ,business.industry ,Middle Aged ,medicine.disease ,Up-Regulation ,Endocrinology ,Kidney Tubules ,RNA ,Female ,business - Abstract
Activation of protein kinase C (PKC) isoforms has been implicated as a central mediator in the pathogenesis of diabetic nephropathy. Although high glucose levels stimulate catalytic activity of PKC, the effects of high glucose levels on the expression of genes encoding PKC isoforms are unknown. We sought to determine whether in addition to activation, diabetes may lead to increased transcription of two PKC isoforms that have been implicated in the pathogenesis of diabetic nephropathy, PKC-alpha and PKC-beta.Recent advances in molecular biological techniques now permit quantitative analysis of mRNA from archival, formalin-fixed, paraffin-embedded tissue sections. RNA was extracted from scraped 6 microm sections of biopsy tissue, and PRKC-alpha and PRKC-beta (also known as PRKCA and PRKCB) mRNA measured using real-time PCR. Expression of genes encoding PKC isoforms was examined in renal biopsies (n=25) with classical histological features of diabetic nephropathy and compared with that in normal control tissue (n=6). Peptide localisation of PKC-alpha, PKC-beta and the activated forms phosphorylated PKC-alpha and -beta was also performed on matched paraffin-embedded sections of renal biopsies using immunohistochemistry. The effects of high glucose on PRKC-beta expression and peptide production in cultured human proximal tubular epithelial cells were assessed.Quantitative real-time PCR demonstrated a 9.9-fold increase in PRKC-beta mRNA in kidney biopsies of diabetic patients relative to control (p0.001). No increase in PRKC-alpha expression was seen. In addition, a correlation between renal PRKC-beta mRNA and HbA(1c) was observed in diabetic patients (r=0.63, p0.05). There was co-localisation of PKC-beta and phospho-PKC-beta predominantly to proximal tubules. A 60% increase in PRKC-beta mRNA and peptide in cultured human proximal tubular epithelial cells exposed to high glucose (p0.05) was seen in vitro.PKC-beta is upregulated at the gene expression level in human diabetic nephropathy. PRKC-beta mRNA correlates closely with serum HbA(1c), possibly partially explaining the relationship between glycaemic control and progression of diabetic nephropathy. Archival human tissue provides a valuable resource for molecular analyses.
- Published
- 2007
42. Isolation, propagation and characterization of primary tubule cell culture from human kidney
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Weier, Qi, David W, Johnson, David A, Vesey, Carol A, Pollock, and Xinming, Chen
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Sodium-Hydrogen Exchangers ,Microvilli ,Cell Culture Techniques ,Povidone ,Epithelial Cells ,Cell Separation ,gamma-Glutamyltransferase ,Alkaline Phosphatase ,Silicon Dioxide ,Tight Junctions ,Kidney Tubules, Proximal ,Centrifugation, Density Gradient ,Humans ,Keratins ,Cell Shape ,Cells, Cultured - Abstract
Proximal tubule cells (PTC) are the major cell type in the cortical tubulointerstitium. Because PTC play a central role in tubulointerstitial pathophysiology, it is essential to prepare pure PTC from kidney tissue to explore the mechanisms of tubulointerstitial pathology. The authors have successfully refined and characterized primary cultures of human PTC using Percoll density gradient centrifugation as a key PTC enrichment step. The cells obtained by this method retain morphological and functional properties of PTC and are minimally contaminated by other renal cells. In particular, the primary isolates have characteristics of epithelial cells with uniform polarized morphology, tight junction and well-formed apical microvilli. Cytokeratin is uniformly and strongly expressed in the isolates. Brush border enzyme activities and PTC transport properties are retained in the isolates. This method therefore provides an excellent in vitro model for the physiologic study of the human proximal tubule.
- Published
- 2007
43. TGF-beta1 induces IL-8 and MCP-1 through a connective tissue growth factor-independent pathway
- Author
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T. Polhill, Xin-Ming Chen, Weier Qi, Richard E. Gilbert, Siska Sumual, Carol A. Pollock, and Stephen M. Twigg
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medicine.medical_specialty ,Physiology ,medicine.medical_treatment ,Connective tissue ,Biology ,Cell Line ,Immediate-Early Proteins ,Kidney Tubules, Proximal ,Transforming Growth Factor beta ,Internal medicine ,TGF beta signaling pathway ,medicine ,Humans ,RNA, Small Interfering ,Chemokine CCL2 ,DNA Primers ,integumentary system ,Base Sequence ,Growth factor ,Interleukin-8 ,Connective Tissue Growth Factor ,Recombinant Proteins ,Cell biology ,CTGF ,medicine.anatomical_structure ,Endocrinology ,Cytokine ,Gene Expression Regulation ,Cell culture ,Tubulointerstitial fibrosis ,Intercellular Signaling Peptides and Proteins ,Transforming growth factor - Abstract
Transforming growth factor-β1 (TGF-β1) functions as an important immunomodulatory cytokine in human kidney. Evidence suggests that connective tissue growth factor (CTGF) is an important downstream mediator of the profibrotic effects of TGF-β1. However, the role of CTGF in TGF-β1-induced chemokine production remains unknown. This study was undertaken to determine whether CTGF is involved in mediating TGF-β1-induced chemokine production in renal proximal tubular (HK-2) cells. Interleukin-8 (IL-8) and macrophage chemoattractant protein-1 (MCP-1) were measured. TGF-β1 induced an increase in IL-8 and MCP-1 (both P < 0.05) compared with control levels. CTGF was effectively silenced using small interference RNA (siRNA) in HK-2 cells. RT-PCR and real-time PCR confirmed a 94% reduction in CTGF mRNA. In the CTGF-silenced cells, TGF-β1-stimulated IL-8 and MCP-1 secretion was not altered compared with control cells. Similarly, basal secretion of IL-8 and MCP-1 was not changed in CTGF-silenced cells. The direct effect of CTGF (20, 200, and 400 ng/ml) on IL-8 and MCP-1 was assessed at 24-, 48-, and 72-h time points and no stimulation was observed. Our studies further demonstrate that in the CTGF gene-silenced cells, CTGF partially mediates TGF-β1-induced fibronectin and collagen IV secretion. These data suggest that TGF-β1 induced IL-8 and MCP-1 via CTGF-independent pathway. TGF-β mediates both fibrosis and chemokine production in the proximal tubule of the kidney. However, CTGF plays a more specific role as a downstream mediator of TGF-β1-induced fibrosis.
- Published
- 2005
44. Regulation of Macrophage Apoptosis and Atherosclerosis by Lipid-Induced PKCδ Isoform Activation.
- Author
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Qian Li, Kyoungmin Park, Yu Xia, Motonobu Matsumoto, Weier Qi, Jialin Fu, Hisashi Yokomizo, Khamaisi, Mogher, Xuanchun Wang, Rask-Madsen, Christian, and King, George L.
- Published
- 2017
- Full Text
- View/download PDF
45. Intervention with tranilast attenuates renal pathology and albuminuria in advanced experimental diabetic nephropathy
- Author
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Carol A. Pollock, Sally Mifsud, Yuan Zhang, Richard E. Gilbert, Darren J. Kelly, Weier Qi, and Jennifer L. Wilkinson-Berka
- Subjects
Collagen Type IV ,medicine.medical_specialty ,Time Factors ,Proline ,Physiology ,Tranilast ,Blotting, Western ,Urology ,Kidney ,Tritium ,Nephropathy ,Diabetes Mellitus, Experimental ,Diabetic nephropathy ,Animals, Genetically Modified ,Rats, Sprague-Dawley ,Mice ,Random Allocation ,Transforming Growth Factor beta ,Physiology (medical) ,Internal medicine ,Diabetes mellitus ,Renin ,medicine ,Albuminuria ,Animals ,Humans ,Diabetic Nephropathies ,ortho-Aminobenzoates ,Cells, Cultured ,business.industry ,Anti-Inflammatory Agents, Non-Steroidal ,Kidney metabolism ,General Medicine ,Fibroblasts ,medicine.disease ,Fibrosis ,Immunohistochemistry ,Fibronectins ,Rats ,Endocrinology ,Renal pathology ,Nephrology ,Female ,medicine.symptom ,Atrophy ,business ,medicine.drug ,Kidney disease - Abstract
Background/Aims: Tubulointerstitial pathology with the accumulation of extracellular matrix are pathological hallmarks of diabetic nephropathy that are directly related to declining renal function. Tranilast (N-[3,4-dimethoxycinnamoyl]anthranilic acid), an inhibitor of transforming growth factor-β (TGF-β), used to treat hypertrophic scars has recently been shown in pilot studies to exert a beneficial effect in advanced diabetic nephropathy in humans. However, its effects on diabetic renal pathology are unknown. Methods: Studies were conducted using a transgenic model, the diabetic (mRen-2)27 rat, which develops many of the structural and functional characteristics of human diabetic nephropathy when diabetes is induced with streptozotocin (STZ). An experimental design was chosen to mimic, in part, the clinical context with drug therapy (tranilast 400 mg/kg/ day) initiated in established disease (8 weeks after STZ) and in the presence of persistent hyperglycaemia and hypertension. Results: At 16 weeks, diabetes was associated with progressive albuminuria, tubulointerstitial fibrosis and tubular atrophy. Without affecting blood pressure or blood glucose, tranilast treatment was associated with a 83% reduction in tubulointerstitial fibrosis (p < 0.001), a 58% reduction in tubular atrophy (p < 0.01) and near normalization of albuminuria (p < 0.05) in diabetic Ren-2 rats. In vitro studies in primary cultures of human renal cortical fibroblasts demonstrated a reduction in TGF-β-induced hydroxyproline incorporation and fibronectin synthesis with tranilast 100 µM. Conclusion: Tranilast, when administered during the course of experimental diabetic nephropathy, attenuates tubulointerstitial pathology and albuminuria. These findings are consistent with the antagonist effects of tranilast on TGF-β actions in the diabetic kidney.
- Published
- 2003
46. Intermittent high glucose enhances cell growth and collagen synthesis in cultured human tubulointerstitial cells
- Author
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Heather J. Saunders, Carol A. Pollock, Weier Qi, and S. C. Jones
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Male ,medicine.medical_specialty ,Platelet-derived growth factor ,Kidney Cortex ,Time Factors ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Biology ,chemistry.chemical_compound ,Transforming Growth Factor beta ,Internal medicine ,Internal Medicine ,medicine ,Humans ,Secretion ,Insulin-Like Growth Factor I ,Cells, Cultured ,Aged ,Platelet-Derived Growth Factor ,Analysis of Variance ,L-Lactate Dehydrogenase ,Cell growth ,Growth factor ,Epithelial Cells ,Transforming growth factor beta ,Kidney Neoplasms ,Cytokine ,Endocrinology ,Glucose ,Insulin-Like Growth Factor Binding Protein 3 ,Kidney Tubules ,chemistry ,biology.protein ,Cytokine secretion ,Female ,Collagen ,Thymidine ,Cell Division - Abstract
Aims/hypothesis. We investigated the effects of constant and intermittently increased glucose concentrations on human proximal tubule cells and cortical fibroblasts in primary culture. Methods. Cells were grown to confluence and then exposed for 4 days to 6.1 mmol/l d-glucose (normal), 25 mmol/l d-glucose (high), or 6.1 mmol/l alternating with 25 mmol/l d-glucose on a daily basis. Results. In proximal tubular cells, exposure to high glucose caused an 11 % increase in thymidine uptake (p < 0.05), a 230 % increase in secretion of transforming growth factor beta 1 (TGF-β1; p < 0.05) and a 393 % increase in platelet derived growth factor. Intermittent exposure to high glucose caused thymidine uptake to further increase by 42 % (p < 0.01) and TGF-β1 secretion by 352 % (p < 0.01) but no additional increase in platelet-derived growth factor secretion was observed. Cellular protein content increased by 27 % (p < 0.05) and collagen synthesis by 29 % (p < 0.05), changes that were not observed in cells constantly exposed to high glucose. In cortical fibroblasts constant exposure to high glucose caused a 35 % increase in thymidine uptake (p < 0.01). Intermittently high glucose increased thymidine incorporation a further 58 % (p < 0.001), collagen synthesis by 65 % (p < 0.01) and insulin-like growth factor binding protein 3 secretion by 216 % (p < 0.01). Conclusion/interpretation. In cultured human tubulointerstitial cells, increased glucose concentrations change cell growth, collagen synthesis and cytokine secretion. These effects are enhanced following intermittent exposure to high glucose, indicating that short lived excursions in glycaemic control have important pathological effects on the human tubulointerstitium. [Diabetologia (1999) 42: 1113–1119]
- Published
- 1999
47. Subject Index Vol. 86, 2000
- Author
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Junne-Ming Sung, V. Terracciano, Tatsuo Hosoya, Yutaka Kobayashi, Ken Okumura, Keiko Uchida, Tatsuya Nakatani, Krasimira Sepetlieva, L. Grcevska, G. Maschio, Ayşegül Örs Zümrütdal, Martin Ellbogen, H. Pasantes-Morales, Yoshiyuki Hiki, Robert Dunlay, Jung-Kuei Pai, Mitsuyoshi Furuhashi, Monika Bulla, Shou-Shan Chiang, Toshiyuki Imasawa, Vladisav Stefanovic, E. Sedano, Halil Uçan, J.L. Pérez-Castrillón, Takanari Aoki, Sumio Tateno, Eri Muso, Vincenzo Bellizzi, M. Polenakovic, M. Milovanceva-Popovska, B.K. Bang, Atsushi Fukatsu, Aysun Karabay Bayazit, Kuddusi Cengiz, Michael Field, M. Arrabal-Martín, Giuseppe La Greca, J.H. Park, I. Villen, Leendert C. Paul, Brad Oldemeyer, Rich Jones, M. Pérez-Suarez, Yukitaka Maruyama, Chie Tomida, Keisuke Yamamoto, Slavenka Janković, Kenji Tsuchida, Johan W. de Fijter, Byung Kee Bang, Harutaka Yamada, Hui Kyung Jeon, Jelena Marinkovic, Jerome G. Porush, Diana Ionova, Yasukazu Yamada, Stefan Fründ, Fumiko Tateyama, Sohji Nagase, Danuta Zwolińska, Y.S. Haviv, Shigetake Sasayama, Adriaan M. Kamper, Isao Ohsawa, Predrag Vlahović, Aki Hirayama, Sun Jeong Lim, Takanobu Sakemi, G. Petruševska, Elsie-C. Chan, Shinichi Kakumu, Yoshihiro Matsumoto, Shu-Yin Kuo, Haruo Tomonari, Robert Kleta, Y.M. Choo, Krystyna Szprynger, Masahiko Nakamoto, Matt Koch, Naoyuki Tamura, Heather J. Saunders, Satoru Tsunoda, Junko Tanaka, Shu-May Lin, Satoru Kuriyama, Izumi Amano, Hitoe Suzuki, Hiroshi Tatsumi, Danica Bukvić, Anna Medyńska, Gopala K. Rangan, Kazuhiro Okano, Tetuhiko Yoshida, Qu Huiqi, Biagio Di Iorio, Morito Endo, Atsushi Yamauchi, Tein-Chung Lu, Wei-Chi Lee, Qiu Mingcai, Maria Szczepańska, Akira Kawashima, Jyh-Gang Leu, J. Möcks, Richard J. Lund, Minako Koike, Mutsuko Hidaka, Mitsuaki Kaizuka, Hideaki Yamabe, Kazuho Honda, Akira Hishida, F.J. Pérez-Blanco, Hassan Izzedine, David A. Vesey, Wey-Wen Jiang, Michihiro Gotoh, Jeng-Jong Huang, G.B. Kim, Hacı Veli Atalay, Fen-Fen Chen, Toshiyuki Takahashi, Kosaku Nitta, Aytül Noyan, Yuet-Ching Tay, J.Y. Choi, P A Conz, Takayuki Fujita, Takako Takita, Lin Shan, Ming-Cheng Wang, Hiroshi Nihei, Tsung Hsiu Wang, C.W. Yang, Gilbert Deray, Young Ok Kim, Sun Ae Yoon, Takashi Uzu, Katsuo Suyama, Atsushi Satomura, Eriya Kikawada, Yau-Huei Wei, Chang Hee Han, Marina Mitić-Zlatković, Ali Anarat, Yoshiaki Takemoto, Ljubica Ðukanović, Hirotsugu Iwatani, Kamen Tcachev, York Leng Yu, Junji Terao, Yiping Wang, Kazumasa Aoyagi, Paik-Seong Lim, A. Zuluaga, Akio Koyama, Wako Yumura, Eun Jung Jun, Arao Futenma, A. Rodríguez-Cuartero, Toshika Okumiya, Atsushi Ueda, Hiroshi Osawa, Weier Qi, Akihiko Kato, Gakusen Nishihara, A. Egon van der Bijl, Yoshiko Baba, Chikao Yasunaga, Aya Abe, Chan Joo Kim, Okan Bakınen, I. Justo-Muradas, Masaya Yamato, Katsumi Takemura, Carlo Crepaldi, Carol A. Pollock, Koichi Suzuki, S. Morales Mulia, Yasuhiro Chikamori, Kenichi Shirato, Naoto Miura, Y.S. Kim, David Harris, Eberhard Kuwertz-Bröking, A.J. Meares, Masatomo Yashiro, Vincent Launay-Vacher, Hiroyuki Ohi, David W. Johnson, E. Saracibar, Hatice Bodur, and Masahiro Kakihara
- Subjects
Index (economics) ,business.industry ,Statistics ,Medicine ,Subject (documents) ,business - Published
- 2000
48. Diabetes mellitus - basic research
- Author
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Sara Cattaneo, Keisuke Satoh, Li Ying, Renate Koppensteiner, Cassia Toledo Bergamaschi, Akira Nishiyama, Ma. Lorena Roldán, Andrew P. Levy, Lislaine A. Wensing, Francesca D'Addio, Maki Takeuchi, Piergiorgio Messa, Benedita Sampaio-Maia, Shigetaka Yoshida, Yoko Saito, Andrea Remuzzi, Hitoshi Nakashima, Elisa Mieko Suemitsu Higa, Maho Watanabe, Fabiola Carrara, Caihong Zeng, Nakhoul Nakhoul, Margaret Gori Mouro, Daniela Corna, Rabea Asleh, Miki Nagase, Hideharu Tanaka, Liliana A. Monasterolo, Romina Pagotto, Michael Brownlee, Jun Okabe, Bi-Cheng Liu, Sho-ichi Yamagishi, Hyung Wook Kim, Mark E. Cooper, Gabriel Cao, Yasuo Kawaba, Carine Prisco Arnoni, Jonathan Barasch, Guoping Zheng, Min Li, Hirotaka Imamaki, Luciana G. Pereira, Akira Sugawara, Masakazu Kohno, Yixin Qian, Tomoko Kawanishi, Manuel Pestana, Hui-Ping Chen, Franck Molina, Silvia Armelloni, Rui Alves, Yanna Dou, Wei-Song Qin, Shinichi Okada, Juliana L. Dreyfuss, Zhangsuo Liu, Seok Joon Shin, Hidenori Arai, Casandra Margarita Monzón, Daniela Rottoli, Reza Abdi, Shan Mou, Alexandre H. Campos, Toru Kita, Li Ya, Hiroshi Kanamori, Yong Gu, Thomas Hoertenhuber, Natsuko Iga, Catia Cerqueira, Shigeru Shibata, Marina Munoz, Maria Pia Rastaldi, Mi Lee, Joanne K. Ferguson, Chi-Chih Hung, Andrea Vergani, Fabio Sangalli, Yiping Wang, Elena Gagliardini, Hassan Kulaksiz, Yukako Kinoshita, Nicolas Salvetat, Li Zhang, Tullio Bertani, Antonio Cabrita, Young Ae Kang, Vincent Lee, Takashige Kuwabara, Daisuke Nakano, Mollie Jurewicz, Toshiro Fujita, Hyun Wha Chung, Rachel Miller-Lotan, Kiyoshi Mori, Muh Geot Wong, Motoaki Saito, Lei-Shi Li, Paula Serrao, Eman El Eter, Yan Qiu, Yi-Mei Hong, Hung-Chun Chen, Christina Maeda Takiya, Romano Nosadini, Birgit Rami, David Harris, Florian Hoellerl, Weier Qi, Zhihong Liu, Ryuji Iwatani, Y. Ogawa, Emi Kazuyama, Mirian A. Boim, Tetsuya Nagae, Kanako Matsubara, Qing Li, Giacomo Garibotto, Li-Min Xu, Kenji Ito, Xiao Ru Huang, Steven J. Harper, Giuseppe Remuzzi, Adelson Marçal Rodrigues, Jiaze Li, Hong-Lang Xie, Takashi Oite, Takuya Ishimura, Margarita Angerosa, Rodrigo Tambellini, Claude Granier, Liu Maodong, Yanling Zhang, Yong-Chun Ge, Ayako Fujimi, Dong Zheng, Yoshimi Takamiya, Mohamed H. Sayegh, Yu-Chi Cheng, Sara Conti, Qingxian Zhang, Hye Kyoung Song, Yu-Yan Fan, Jackson Souza-Menezes, Masashi Mukoyama, Hideki Yokoi, Xin Ming Chen, Ma. Mónica Elías, Zhai Shana, Melina A. Pagotto, Lorena Longaretti, Yonghong Shi, Assam El-Osta, Carol A. Pollock, Zanzhe Yu, Jad Kheir, Yoon Sik Chang, Takao Saito, Maha El Enazy, Laura Giardino, Ya Wang, Aneta Balcerczyk, Raquel C. Castiglione, Alessio Mocci, Sharma Prabhakar, Piotr Ksiazek, Ariela Benigni, Carla Zoja, Edith Schober, Shi Yonghong, Yan Sun, Duo Li, Wei-Wei Zhu, Yi-chun Tsai, Stephen I. Alexander, Seiya Okuda, Qi Cao, Edgar Maquigussa, Cheol Whee Park, Sara Molinas, Takako Mizutani, Kei Fukami, Yusuke Kaida, Paulo Roberto Santos, Jee Han, Lin Tang, Wakako Kawarazaki, Noriko Satoh, Alex Yuri S. Sato, Hui Y. Lan, Anabela Almeida, Zhang Yanling, Zhaohui Ni, David Barit, Susumu Kanzaki, Jiaqi Qian, Yukinori Tamura, Farid Nakhoul, David O. Bates, Fernando Dominici, Arthur C.K. Chung, Shirine Dada, Ying Li, Ji Hee Lim, Leyi Gu, Zhao-Hong Chen, Gastón Rojic, Sungjin Chung, Paolo Fiorina, Felipe M. Ornellas, Dae Cha, Roy Asaf, Huili Dai, Itaru Satoh, Laura Trumper, Masato Kasahara, Kazuwa Nakao, Jorge Giani, Carolina M.L. Barbosa, Oh Yeun Kwon, Atsushi Fukatsu, Jorge Toblli, Weiming Zhan, Alexander J. Szalai, Hoda Awad, Kiyomi Koike, Atsushi Hayashi, Shanyan Lin, Yucheng Yan, Fei Liu, Anna Watson, Sabine Peres, Jun Gao, Andrew H.J. Salmon, Faical Jarraya, Karin Jandeleit-Dahm, Monica Moreira-Rodrigues, Omar P. Pignataro, Gerit-Holger Schernthaner, Andrea Augello, Guntram Schernthaner, Giuseppe Garigali, Marcelo M. Morales, Michal Dragan, Hiroyuki Kobori, Monika Buraczynska, Grazyna Orlowska-Kowalik, Daniella Brasacchio, Janete Quelhas-Santos, Tatiana Maron-GutierrezGutierrez, Seiji Ueda, and Guo Quin Wang
- Subjects
Transplantation ,medicine.medical_specialty ,Nephrology ,business.industry ,Basic research ,Diabetes mellitus ,Medicine ,business ,Intensive care medicine ,medicine.disease - Published
- 2009
49. Contents Vol. 95, 2003
- Author
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Serge M. Gisler, Lynn R. Willis, Sandra Pribanic, Jennifer L. Wilkinson-Berka, Jürg Biber, Yuan Zhang, Ryan F. Paterson, Jay R. Simon, Arieh L. Shalhav, Ramsay L. Kuo, Jan Loffing, Weier Qi, Naomi S. Fineberg, Carol A. Pollock, Karl-Heinz Braunewell, David A. Lifshitz, Richard E. Gilbert, Sally Mifsud, Darren J. Kelly, Caveh Madjdpour, James E. Lingeman, Bret A. Connors, Andrew P. Evan, Desa Bacic, and Heini Murer
- Subjects
Nephrology ,Physiology ,Physiology (medical) ,General Medicine ,Biology - Published
- 2003
50. HIGH GLUCOSE UPREGULATES PLASMINOGEN ACTIVATOR INHIBITOR-1 (PAI-1) IN HUMAN PROXIMAL TUBULAR CELLS (PTCS) AND CORTICAL FIBROBLASTS (CFS)
- Author
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Philip Poronnik, Carol A. Pollock, Weier Qi, Michael Field, and C Jackson
- Subjects
medicine.medical_specialty ,chemistry.chemical_compound ,Endocrinology ,chemistry ,Nephrology ,business.industry ,Internal medicine ,Plasminogen activator inhibitor-1 ,High glucose ,medicine ,General Medicine ,business - Published
- 2002
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