111 results on '"Gu HM"'
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2. Using an oblique incident laser beam to measure the optical properties of stomach mucosa/submucosa tissue.
- Author
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Wei HJ, Xing D, He BH, Gu HM, Wu GY, Chen XM, Wei, Hua Jiang, Xing, Da, He, Bo Hua, Gu, Huai Min, Wu, Guo Yong, and Chen, Xue Mei
- Abstract
Background: The purpose of the study is to determine the optical properties and their differences for normal human stomach mucosa/submucosa tissue in the cardiac orifice in vitro at 635, 730, 808, 890 and 980 nm wavelengths of laser.Methods: The measurements were performed using a CCD detector, and the optical properties were assessed from the measurements using the spatially resolved reflectance, and nonlinear fitting of diffusion equation.Results: The results of measurement showed that the absorption coefficients, the reduced scattering coefficients, the optical penetration depths, the diffusion coefficients, the diffuse reflectance and the shifts of diffuse reflectance of tissue samples at five different wavelengths vary with a change of wavelength. The maximum absorption coefficient for tissue samples is 0.265 mm-1 at 980 nm, and the minimum absorption coefficient is 0.0332 mm-1 at 730 nm, and the maximum difference in the absorption coefficients is 698% between 730 and 980 nm, and the minimum difference is 1.61% between 635 and 808 nm. The maximum reduced scattering coefficient for tissue samples is 1.19 mm-1 at 635 nm, and the minimum reduced scattering coefficient is 0.521 mm-1 at 980 nm, and the maximum difference in the reduced scattering coefficients is 128% between 635 and 980 nm, and the minimum difference is 1.15% between 890 and 980 nm. The maximum optical penetration depth for tissue samples is 3.57 mm at 808 nm, and the minimum optical penetration depth is 1.43 mm at 980 nm. The maximum diffusion constant for tissue samples is 0.608 mm at 890 nm, and the minimum diffusion constant is 0.278 mm at 635 nm. The maximum diffuse reflectance is 3.57 mm-1 at 808 nm, and the minimum diffuse reflectance is 1.43 mm-1 at 980 nm. The maximum shift Deltax of diffuse reflectance is 1.11 mm-1 at 890 nm, and the minimum shift Deltax of diffuse reflectance is 0.507 mm-1 at 635 nm.Conclusion: The absorption coefficients, the reduced scattering coefficients, the optical penetration depths, the diffusion coefficients, the diffuse reflectance and the shifts of diffuse reflectance of tissue samples at 635, 730, 808, 890 and 980 nm wavelengths vary with a change of wavelength. There were significant differences in the optical properties for tissue samples at five different wavelengths (P < 0.01). [ABSTRACT FROM AUTHOR]- Published
- 2009
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3. Inducible global knockout of surfeit locus protein 4 in adult mice results in hypolipidemia, intestinal lipid accumulation, liver injury, and increased mortality.
- Author
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Chen W, Chen Y, Song B, Zhai L, Tao G, Wang B, Liu B, Wang H, Zhang CX, Gu HM, Yin D, Qin S, and Zhang DW
- Abstract
Surfeit locus protein 4 (SURF4) acts as a cargo receptor to mediate endoplasmic reticulum export of various cargos. We have shown that SURF4 is essential for secretion of hepatic very low-density lipoprotein and intestinal chylomicron. Knockdown of hepatic Surf4 also significantly reduces the development of atherosclerosis and liver fibrosis without causing overt liver damage. However, constitutive global Surf4 knockout results in embryonic lethality. To further understand the physiological role of SURF4, we generated tamoxifen-inducible global Surf4 knockout mice. We found that conditional knockout of Surf4 in adult mice (Surf4
ig-ko ) significantly reduced mouse body weight. Male and female Surf4ig-ko mice died approximately 30 and 50 days after tamoxifen administration, respectively. Triglyceride secretion and serum levels of total cholesterol, triglycerides, free fatty acids, apolipoprotein B-100, and apolipoprotein B-48 were significantly reduced in Surf4ig-ko mice compared with Surf4flox mice. Proteomics analysis of mouse serum samples revealed 308 proteins with significantly altered expression in Surf4ig-ko mice that have unique functions and are involved in various biological processes. In addition, Surf4ig-ko mice exhibited lipid accumulation in the intestine but not in the liver. However, in Surf4ig-ko mice, liver weight was significantly reduced, and serum transaminase activity was significantly increased, indicating liver damage. Therefore, SURF4 is essential for survival in adult mice, suggesting that the therapeutic use of SURF4 requires precise tissue/cell type-specific targeting., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)- Published
- 2024
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4. Impact of diabetes mellitus and hypertension on renal function during first-line targeted therapy for metastatic renal cell carcinoma: a retrospective multicenter study.
- Author
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Gu HM, Sou SJ, Ku JY, Kim KH, Park YJ, Choi SH, Ha HK, Hwang EC, and Lee CH
- Abstract
Background: Renal function deterioration during systemic therapy in patients with metastatic renal cell carcinoma (mRCC) is a long-term concern in treatment planning. Although hypertension (HTN) and diabetes mellitus (DM) are the most common factors that affect chronic kidney disease (CKD) development and progression, their impact on renal function during targeted therapy is unclear. This study investigated whether DM and HTN were associated with a decline in renal function during first-line targeted therapy for mRCC., Methods: This retrospective multicenter study analyzed patients receiving first-line targeted therapy for mRCC. They were classified as follows: group 1: HTN-, DM-; group 2: HTN+, DM-; group 3: HTN-, DM+; and group 4: HTN+, DM+. Changes in renal function and factors affecting progression to stage 4 CKD after targeted therapy were analyzed., Results: Among the 424 enrolled patients, 303 (71.5%) and 121 (28.5%) were treated with sunitinib and pazopanib, respectively [median duration: 10.3 months, interquartile range (IQR), 3.1-37.0 months]. Although all groups showed a decreased mean estimated glomerular filtration rate (eGFR) after treatment (P<0.001 for group 1, group 2, and group 4, P=0.02 for group 3, respectively), there were no significant differences in changes in eGFR (∆eGFR) between groups (P=0.10). However, actual renal function change calculated using percent ∆eGFR (%∆eGFR) showed differences between groups (P=0.02); the %∆eGFR of group 4 was significantly lower compared with group 1 (P=0.008). The mean progression time to stage 4 CKD in group 4 (38.6 months) was significantly shorter compared to the other groups (P<0.001). Multivariate analysis identified increased age (P=0.008), increased number of metastatic sites (P=0.047), and DM and HTN coexistence (P<0.001) as predictors of progression to stage 4 CKD., Conclusions: Patients with DM and HTN experienced further decline in renal function and had a higher risk of progression to stage 4 CKD after targeted therapy compared to patients without these risk factors. Recognition and proactive management of DM and HTN are necessary to facilitate the proper administration of life-prolonging oncological treatments., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tau.amegroups.com/article/view/10.21037/tau-24-231/coif). C.H.L. reports the funding from the 2023 Inje University research grant. The other authors have no conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)
- Published
- 2024
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5. The spectrum of novel ABCB11 gene variations in children with progressive familial intrahepatic cholestasis type 2 in Pakistani cohorts.
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Riaz H, Zheng B, Zheng Y, Liu Z, Gu HM, Imran M, Yaqoob T, Bhinder MA, Zhang DW, and Zahoor MY
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- Humans, Pakistan, Male, Female, Child, Child, Preschool, Infant, Mutation, Exons genetics, Cohort Studies, Homozygote, ATP Binding Cassette Transporter, Subfamily B, Member 11 genetics, Cholestasis, Intrahepatic genetics
- Abstract
Progressive familial intrahepatic cholestasis (PFIC) is a rare childhood manifested disease associated with impaired bile secretion with severe pruritus yellow stool, and sometimes hepatosplenomegaly. PFIC is caused by mutations in ATP8B1, ABCB11, ABCB4, TJP2, NR1H4, SLC51A, USP53, KIF12, ZFYVE19, and MYO5B genes depending on its type. ABCB11 mutations lead to PFIC2 that encodes the bile salt export pump (BSEP). Different mutations of ABCB11 have been reported in different population groups but no data available in Pakistani population being a consanguineous one. We sequenced coding exons of the ABCB11 gene along with its flanking regions in 66 unrelated Pakistani children along with parents with PFIC2 phenotype. We identified 20 variations of ABCB11: 12 in homozygous form, one compound heterozygous, and seven heterozygous. These variants include 11 missenses, two frameshifts, two nonsense mutations, and five splicing variants. Seven variants are novel candidate variants and are not detected in any of the 120 chromosomes from normal ethnically matched individuals. Insilico analysis revealed that four homozygous missense variations have high pathogenic scores. Minigene analysis of splicing variants showed exon skipping and the addition of exon. This data is a useful addition to the disease variants genomic database and would be used in the future to build a diagnostic algorithm., (© 2024. The Author(s).)
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- 2024
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6. Hepatic Surf4 Deficiency Impairs Serum Amyloid A1 Secretion and Attenuates Liver Fibrosis in Mice.
- Author
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Wang B, Li H, Gill G, Zhang X, Tao G, Liu B, Zhai L, Chen W, Wang H, Gu HM, Qin S, and Zhang DW
- Abstract
Liver fibrosis is a severe global health problem. However, no effective antifibrotic drugs have been approved. Surf4 is primarily located in the endoplasmic reticulum (ER) and mediates the transport of secreted proteins from the ER to the Golgi apparatus. Knockout of hepatic Surf4 ( Surf4
LKO ) in mice impairs very-low-density lipoprotein secretion without causing overt liver damage. Here, we found that collagen levels are significantly reduced in the liver of Surf4LKO mice compared with control Surf4flox mice, as demonstrated by proteomics, Western blot, and quantitative reverse transcription polymerase chain reaction. Therefore, this study aims to investigate whether and how hepatic Surf4 affects liver fibrosis. We observed that CCl4 -induced liver fibrosis is significantly lower in Surf4LKO mice than in Surf4flox mice. Mechanistically, hepatic Surf4 deficiency reduces serum amyloid A1 (SAA1) secretion and hepatic stellate cell (HSC) activation. Surf4 coimmunoprecipitates and colocalizes with SAA1. Lack of hepatic Surf4 significantly reduces SAA1 secretion from hepatocytes, and SAA1 activates cultured human HSCs (LX-2 cells). Conditioned medium (CM) from Surf4-deficient primary hepatocytes activates LX-2 cells to a much lesser extent than CM from Surf4flox primary hepatocytes, and this reduced effect is restored by the addition of recombinant SAA1 to CM from Surf4-deficient hepatocytes. Knockdown of SAA1 in primary hepatocytes or TLR2 in LX-2 cells significantly reduces LX-2 activation induced by CM from Surf4flox hepatocytes but not from Surf4LKO hepatocytes. Furthermore, knockdown of SAA1 significantly ameliorates liver fibrosis in Surf4flox mice but does not further reduce liver fibrosis in Surf4LKO mice. We also observe substantial expression of Surf4 and SAA1 in human fibrotic livers. Therefore, hepatic Surf4 facilitates SAA1 secretion, activates HSCs, and aggravates liver fibrosis, suggesting that hepatic Surf4 and SAA1 may serve as treatment targets for liver fibrosis., Competing Interests: Competing interests: The authors declare that they have no competing interests., (Copyright © 2024 Bingxiang Wang et al.)- Published
- 2024
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7. Cancer risk associated with low-dose ionizing radiation: A systematic review of epidemiological and biological evidence.
- Author
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Tao SM, Wang LL, Li MD, Wang J, Gu HM, and Zhang LJ
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- Humans, DNA Damage radiation effects, Animals, Dose-Response Relationship, Radiation, Neoplasms etiology, Neoplasms epidemiology, Risk Factors, Neoplasms, Radiation-Induced epidemiology, Neoplasms, Radiation-Induced genetics, Neoplasms, Radiation-Induced etiology, Radiation, Ionizing
- Abstract
The current radiation protection reference standards on stochastic cancer risk, drafted by the International Committee on Radiation Protection, are mostly based on the Life Span Study (LSS), though sufficient epidemiological and basic research evidence is lacking. The relationship between low-dose ionizing radiation (LDIR) and cancer risk is currently modeled with linear non-threshold (LNT) models. However, with the widespread use of medical examinations, the demand for substantial evidence of cancer risk under LDIR and the establishment of a threshold has become more significant. In the first part of the review, we summarize pivotal research in epidemiology, which includes the LSS, medical radiation studies, and occupational and environmental exposure studies. We describe and discuss solid cancers and hematopoietic malignancies induced by LDIR separately, attempting to identify the consistency and differences in the research results, and offering suggestions for future research directions. In the second part, we review recent progress in the underlying biology of cancer associated with LDIR. Besides the obvious harmful effect of DNA damage, chromosome aberrations caused by LDIR, epigenetic regulation also requires attention due to their relationship with carcinogenic and genetic risk. The multistage carcinogenesis model of stem cells, along with the varying effects of radiation on different tumors, may challenge the LNT model. Related research of stem cells, mitochondria and omic biology also offers promising directions for future research in this field., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)
- Published
- 2024
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8. GDF11 slows excitatory neuronal senescence and brain ageing by repressing p21.
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Wang DX, Dong ZJ, Deng SX, Tian YM, Xiao YJ, Li X, Ma XR, Li L, Li P, Chang HZ, Liu L, Wang F, Wu Y, Gao X, Zheng SS, Gu HM, Zhang YN, Wu JB, Wu F, Peng Y, Zhang XW, Zhan RY, Gao LX, Sun Q, Guo X, Zhao XD, Luo JH, Zhou R, Han L, Shu Y, and Zhao JW
- Subjects
- Adult, Mice, Humans, Animals, Aging genetics, Brain metabolism, Neurons metabolism, Bone Morphogenetic Proteins, Caenorhabditis elegans metabolism, Growth Differentiation Factors genetics, Growth Differentiation Factors metabolism
- Abstract
As a major neuron type in the brain, the excitatory neuron (EN) regulates the lifespan in C. elegans. How the EN acquires senescence, however, is unknown. Here, we show that growth differentiation factor 11 (GDF11) is predominantly expressed in the EN in the adult mouse, marmoset and human brain. In mice, selective knock-out of GDF11 in the post-mitotic EN shapes the brain ageing-related transcriptional profile, induces EN senescence and hyperexcitability, prunes their dendrites, impedes their synaptic input, impairs object recognition memory and shortens the lifespan, establishing a functional link between GDF11, brain ageing and cognition. In vitro GDF11 deletion causes cellular senescence in Neuro-2a cells. Mechanistically, GDF11 deletion induces neuronal senescence via Smad2-induced transcription of the pro-senescence factor p21. This work indicates that endogenous GDF11 acts as a brake on EN senescence and brain ageing., (© 2023. The Author(s).)
- Published
- 2023
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9. Extracellular matrix turnover: phytochemicals target and modulate the dual role of matrix metalloproteinases (MMPs) in liver fibrosis.
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Sabir U, Gu HM, and Zhang DW
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- Animals, Phytochemicals pharmacology, Phytochemicals therapeutic use, Disease Progression, Liver Cirrhosis drug therapy, Extracellular Matrix metabolism
- Abstract
Extracellular matrix (ECM) resolution by matrix metalloproteinases (MMPs) is a well-documented mechanism. MMPs play a dual and complex role in modulating ECM degradation at different stages of liver fibrosis, depending on the timing and levels of their expression. Increased MMP-1 combats disease progression by cleaving the fibrillar ECM. Activated hepatic stellate cells (HSCs) increase expression of MMP-2, -9, and -13 in different chemicals-induced animal models, which may alleviate or worsen disease progression based on animal models and the stage of liver fibrosis. In the early stage, elevated expression of certain MMPs may damage surrounding tissue and activate HSCs, promoting fibrosis progression. At the later stage, downregulation of MMPs can facilitate ECM accumulation and disease progression. A number of phytochemicals modulate MMP activity and ECM turnover, alleviating disease progression. However, the effects of phytochemicals on the expression of different MMPs are variable and may depend on the disease models and stage, and the dosage, timing and duration of phytochemicals used in each study. Here, we review the most recent advances in the role of MMPs in the effects of phytochemicals on liver fibrogenesis, which indicates that further studies are warranted to confirm and define the potential clinical efficacy of these phytochemicals., (© 2023 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd.)
- Published
- 2023
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10. Global, but not chondrocyte-specific, MT1-MMP deficiency in adult mice causes inflammatory arthritis.
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Xia XD, Gill G, Lin H, Roth DM, Gu HM, Wang XJ, Su FY, Alabi A, Alexiou M, Zhang Z, Wang GQ, Graf D, and Zhang DW
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- Animals, Mice, Blood Glucose, Body Weight, Matrix Metalloproteinase 14 genetics, Cartilage, Articular, Osteoarthritis chemically induced, Osteoarthritis genetics
- Abstract
Membrane-type I metalloproteinase (MT1-MMP/MMP14) plays a key role in various pathophysiological processes, indicating an unaddressed need for a targeted therapeutic approach. However, mice genetically deficient in Mmp14 show severe defects in development and growth. To investigate the possibility of MT1-MMP inhibition as a safe treatment in adults, we generated global Mmp14 tamoxifen-induced conditional knockout (Mmp14
kd ) mice and found that MT1-MMP deficiency in adult mice resulted in severe inflammatory arthritis. Mmp14kd mice started to show noticeably swollen joints two weeks after tamoxifen administration, which progressed rapidly. Mmp14kd mice reached a humane endpoint 6 to 8 weeks after tamoxifen administration due to severe arthritis. Plasma TNF-α levels were also significantly increased in Mmp14kd mice. Detailed analysis revealed chondrocyte hypertrophy, synovial fibrosis, and subchondral bone remodeling in the joints of Mmp14kd mice. However, global conditional knockout of MT1-MMP in adult mice did not affect body weight, blood glucose, or plasma cholesterol and triglyceride levels. Furthermore, we observed substantial expression of MT1-MMP in the articular cartilage of patients with osteoarthritis. We then developed chondrocyte-specific Mmp14 tamoxifen-induced conditional knockout (Mmp14chkd ) mice. Chondrocyte MT1-MMP deficiency in adult mice also caused apparent chondrocyte hypertrophy. However, Mmp14chkd mice did not exhibit synovial hyperplasia or noticeable arthritis, suggesting that chondrocyte MT1-MMP is not solely responsible for the onset of severe arthritis observed in Mmp14kd mice. Our findings also suggest that highly cell-type specific inhibition of MT1-MMP is required for its potential therapeutic use., Competing Interests: Declaration of Competing Interest The authors have declared no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)- Published
- 2023
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11. Corrigendum: Loss of hepatic Surf4 depletes lipid droplets in the adrenal cortex but does not impair adrenal hormone production.
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Chang X, Zhao Y, Qin S, Wang H, Wang B, Zhai L, Liu B, Gu HM, and Zhang DW
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[This corrects the article DOI: 10.3389/fcvm.2021.764024.]., (© 2023 Chang, Zhao, Qin, Wang, Wang, Zhai, Liu, Gu and Zhang.)
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- 2023
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12. Fosfomycin for Antibiotic Prophylaxis in Men Undergoing a Transrectal Prostate Biopsy: A Systematic Review and Meta-Analysis.
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Gu HM, Gu JS, Chung HS, Jung SI, Kwon D, Kim MH, Jung JH, Han MA, Kang SJ, Hwang EC, and Dahm P
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- Male, Humans, Antibiotic Prophylaxis methods, Prostate pathology, Anti-Bacterial Agents therapeutic use, Biopsy adverse effects, Fluoroquinolones therapeutic use, Fosfomycin therapeutic use, Urinary Tract Infections epidemiology, Urinary Tract Infections prevention & control, Urinary Tract Infections drug therapy
- Abstract
Background and Objectives: To assess the effects of fosfomycin compared with other antibiotics as a prophylaxis for urinary tract infections (UTIs) in men undergoing transrectal prostate biopsies. Materials and Methods: We searched multiple databases and trial registries without publication language or status restrictions until 4 January 2022. Parallel-group randomized controlled trials (RCTs) and non-randomized studies (NRS) were included. The primary outcomes were febrile UTI, afebrile UTI, and overall UTI. We used GRADE guidance to rate the certainty of evidence of RCTs and NRSs. The protocol was registered with PROSPERO (CRD42022302743). Results: We found data on five comparisons; however, this abstract focuses on the primary outcomes of the two most clinically relevant comparisons. Regarding fosfomycin versus fluoroquinolone, five RCTs and four NRSs with a one-month follow-up were included. Based on the RCT evidence, fosfomycin likely resulted in little to no difference in febrile UTIs compared with fluoroquinolone. This difference corresponded to four fewer febrile UTIs per 1000 patients. Fosfomycin likely resulted in little to no difference in afebrile UTIs compared with fluoroquinolone. This difference corresponded to 29 fewer afebrile UTIs per 1000 patients. Fosfomycin likely resulted in little to no difference in overall UTIs compared with fluoroquinolone. This difference corresponded to 35 fewer overall UTIs per 1000 patients. Regarding fosfomycin and fluoroquinolone combined versus fluoroquinolone, two NRSs with a one- to three-month follow-up were included. Based on the NRS evidence, fosfomycin and fluoroquinolone combined may result in little to no difference in febrile UTIs compared with fluoroquinolone. This difference corresponded to 16 fewer febrile UTIs per 1000 patients. Conclusions: Compared with fluoroquinolone, fosfomycin or fosfomycin and fluoroquinolone combined may have a similar prophylactic effect on UTIs after a transrectal prostate biopsy. Given the increasing fluoroquinolone resistance and its ease to use, fosfomycin may be a good option for antibiotic prophylaxis.
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- 2023
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13. Surf4 (Surfeit Locus Protein 4) Deficiency Reduces Intestinal Lipid Absorption and Secretion and Decreases Metabolism in Mice.
- Author
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Tao G, Wang H, Shen Y, Zhai L, Liu B, Wang B, Chen W, Xing S, Chen Y, Gu HM, Qin S, and Zhang DW
- Subjects
- Humans, Male, Animals, Mice, Caco-2 Cells, Intestinal Absorption physiology, Dietary Fats, Chylomicrons metabolism, Lipid Metabolism genetics, Triglycerides metabolism, Membrane Proteins genetics, Membrane Proteins metabolism, Intestinal Mucosa metabolism, Atherosclerosis metabolism
- Abstract
Background: Postprandial dyslipidemia is a causative risk factor for cardiovascular disease. The majority of absorbed dietary lipids are packaged into chylomicron and then delivered to circulation. Previous studies showed that Surf4 (surfeit locus protein 4) mediates very low-density lipoprotein secretion from hepatocytes. Silencing hepatic Surf4 markedly reduces the development of atherosclerosis in different mouse models of atherosclerosis without causing hepatic steatosis. However, the role of Surf4 in chylomicron secretion is unknown., Methods: We developed inducible intestinal-specific Surf4 knockdown mice ( Surf4
IKO ) using Vil 1Cre-ERT2 and Surf4flox mice. Metabolic cages were used to monitor mouse metabolism. Enzymatic kits were employed to measure serum and tissue lipid levels. The expression of target genes was detected by qRT-PCR and Western Blot. Transmission electron microscopy and radiolabeled oleic acid were used to assess the structure of enterocytes and intestinal lipid absorption and secretion, respectively. Proteomics was performed to determine changes in protein expression in serum and jejunum., Results: Surf4IKO mice, especially male Surf4IKO mice, displayed significant body weight loss, increased mortality, and reduced metabolism. Surf4IKO mice exhibited lipid accumulation in enterocytes and impaired fat absorption and secretion. Lipid droplets and small lipid vacuoles were accumulated in the cytosol and the endoplasmic reticulum lumen of the enterocytes of Surf4IKO mice, respectively. Surf4 colocalized with apoB and co-immunoprecipitated with apoB48 in differentiated Caco-2 cells. Intestinal Surf4 deficiency also significantly reduced serum triglyceride, cholesterol, and free fatty acid levels in mice. Proteomics data revealed that diverse pathways were altered in Surf4IKO mice. In addition, Surf4IKO mice had mild liver damage, decreased liver size and weight, and reduced hepatic triglyceride levels., Conclusions: Our findings demonstrate that intestinal Surf4 plays an essential role in lipid absorption and chylomicron secretion and suggest that the therapeutic use of Surf4 inhibition requires highly cell/tissue-specific targeting.- Published
- 2023
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14. Surf4, cargo trafficking, lipid metabolism, and therapeutic implications.
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Shen Y, Gu HM, Qin S, and Zhang DW
- Subjects
- Humans, Golgi Apparatus metabolism, Proprotein Convertase 9 metabolism, Protein Transport genetics, Protein Transport physiology, Lipid Metabolism, Membrane Proteins metabolism
- Abstract
Surfeit 4 is a polytopic transmembrane protein that primarily resides in the endoplasmic reticulum (ER) membrane. It is ubiquitously expressed and functions as a cargo receptor, mediating cargo transport from the ER to the Golgi apparatus via the canonical coat protein complex II (COPII)-coated vesicles or specific vesicles. It also participates in ER-Golgi protein trafficking through a tubular network. Meanwhile, it facilitates retrograde transportation of cargos from the Golgi apparatus to the ER through COPI-coated vesicles. Surf4 can selectively mediate export of diverse cargos, such as PCSK9 very low-density lipoprotein (VLDL), progranulin, α1-antitrypsin, STING, proinsulin, and erythropoietin. It has been implicated in facilitating VLDL secretion, promoting cell proliferation and migration, and increasing replication of positive-strand RNA viruses. Therefore, Surf4 plays a crucial role in various physiological and pathophysiological processes and emerges as a promising therapeutic target. However, the molecular mechanisms by which Surf4 selectively sorts diverse cargos for ER-Golgi protein trafficking remain elusive. Here, we summarize the most recent advances in Surf4, focusing on its role in lipid metabolism., (© The Author(s) (2022). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, CEMCS, CAS.)
- Published
- 2023
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15. Editorial: Lipid metabolism and human diseases.
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Amadi PU, Gu HM, Yin K, Jiang XC, and Zhang DW
- Abstract
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
- Published
- 2022
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16. The role of hepatic Surf4 in lipoprotein metabolism and the development of atherosclerosis in apoE -/- mice.
- Author
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Shen Y, Gu HM, Zhai L, Wang B, Qin S, and Zhang DW
- Subjects
- Animals, Apolipoproteins E metabolism, Cholesterol metabolism, Cholesterol, LDL metabolism, Lipoproteins, VLDL metabolism, Liver metabolism, Membrane Proteins genetics, Membrane Proteins metabolism, Mice, Triglycerides metabolism, Atherosclerosis metabolism, Cardiovascular Diseases metabolism
- Abstract
Elevated plasma levels of low-density lipoprotein-C (LDL-C) increase the risk of atherosclerotic cardiovascular disease. Circulating LDL is derived from very low-density lipoprotein (VLDL) metabolism and cleared by LDL receptor (LDLR). We have previously demonstrated that cargo receptor Surfeit 4 (Surf4) mediates VLDL secretion. Inhibition of hepatic Surf4 impairs VLDL secretion, significantly reduces plasma LDL-C levels, and markedly mitigates the development of atherosclerosis in LDLR knockout (Ldlr
-/- ) mice. Here, we investigated the role of Surf4 in lipoprotein metabolism and the development of atherosclerosis in another commonly used mouse model of atherosclerosis, apolipoprotein E knockout (apoE-/- ) mice. Adeno-associated viral shRNA was used to silence Surf4 expression mainly in the liver of apoE-/- mice. In apoE-/- mice fed a regular chow diet, knockdown of Surf4 expression significantly reduced triglyceride secretion and plasma levels of non-HDL cholesterol and triglycerides without causing hepatic lipid accumulation or liver damage. When Surf4 was knocked down in apoE-/- mice fed the Western-type diet, we observed a significant reduction in plasma levels of non-HDL cholesterol, but not triglycerides. Knockdown of Surf4 did not increase hepatic cholesterol and triglyceride levels or cause liver damage, but significantly diminished atherosclerosis lesions. Therefore, our findings indicate the potential of hepatic Surf4 inhibition as a novel therapeutic strategy to reduce the risk of atherosclerotic cardiovascular disease., (Copyright © 2022. Published by Elsevier B.V.)- Published
- 2022
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17. Identification of amino acid residues in the MT-loop of MT1-MMP critical for its ability to cleave low-density lipoprotein receptor.
- Author
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Wang M, Alabi A, Gu HM, Gill G, Zhang Z, Jarad S, Xia XD, Shen Y, Wang GQ, and Zhang DW
- Abstract
Low-density lipoprotein receptor (LDLR) mediates clearance of plasma LDL cholesterol, preventing the development of atherosclerosis. We previously demonstrated that membrane type 1-matrix metalloproteinase (MT1-MMP) cleaves LDLR and exacerbates the development of atherosclerosis. Here, we investigated determinants in LDLR and MT1-MMP that were critical for MT1-MMP-induced LDLR cleavage. We observed that deletion of various functional domains in LDLR or removal of each of the five predicted cleavage sites of MT1-MMP on LDLR did not affect MT1-MMP-induced cleavage of the receptor. Removal of the hemopexin domain or the C-terminal cytoplasmic tail of MT1-MMP also did not impair its ability to cleave LDLR. On the other hand, mutant MT1-MMP, in which the catalytic domain or the MT-loop was deleted, could not cleave LDLR. Further Ala-scanning analysis revealed an important role for Ile at position 167 of the MT-loop in MT1-MMP's action on LDLR. Replacement of Ile167 with Ala, Thr, Glu, or Lys resulted in a marked loss of the ability to cleave LDLR, whereas mutation of Ile167 to a non-polar amino acid residue, including Leu, Val, Met, and Phe, had no effect. Therefore, our studies indicate that MT1-MMP does not require a specific cleavage site on LDLR. In contrast, an amino acid residue with a hydrophobic side chain at position 167 in the MT-loop is critical for MT1-MMP-induced LDLR cleavage., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Alabi, Gu, Gill, Zhang, Jarad, Xia, Shen, Wang and Zhang.)
- Published
- 2022
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18. Author Correction: Magnesium isoglycyrrhizinate ameliorates high fructose-induced liver fibrosis in rat by increasing miR-375-3p to suppress JAK2/STAT3 pathway and TGF-β1/Smad signaling.
- Author
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Yang YZ, Zhao XJ, Xu HJ, Wang SC, Pan Y, Wang SJ, Xu Q, Jiao RQ, Gu HM, and Kong LD
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- 2022
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19. Outcomes of elderly patients with traumatic brain injury associated with the pre-injury antithrombotic prophylaxis type - A systematic review and meta-analysis.
- Author
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Liu YL, Yin L, Gu HM, Zhu XJ, and Huang XX
- Subjects
- Aged, Aged, 80 and over, Fibrinolytic Agents adverse effects, Humans, Intracranial Hemorrhages, Length of Stay, Anticoagulants adverse effects, Brain Injuries, Traumatic complications, Brain Injuries, Traumatic drug therapy
- Abstract
Objective: Our review aims at comparing the morbidity and mortality-related risks associated with the pre-injury administration of VK-antagonists or DOACs in elderly patients with TBI., Materials and Methods: We performed a systematic search of the academic literature across five databases (Web of Science, EMBASE, CENTRAL, Scopus, and MEDLINE), following PRISMA guidelines. We conducted a random-effect meta-analysis to compare the influence of pre-injury VK-antagonists or DOACs administration on the overall intensive care unit and hospital stays of patients with TBI. We also evaluated the overall risks associated with VK-antagonists and with DOACs for intracranial hemorrhage progression, surgical intervention, and overall mortality in patients with TBI., Results: From 973 studies, we found 11 eligible with 4,991 patients with traumatic brain injury (mean age, 77.82 ± 6.76 years). Our meta-analysis revealed insignificantly higher odds of surgical intervention (OR=1.72) and mortality (OR=1.07) associated with VK-antagonists administration than with DOACs administration. Similarly, we found that the intensive care unit (Hedge's g, 0.13) and hospital (g, 0.26) stays were insignificantly longer for individuals on VK-antagonists than for those on DOAC. Moreover, we observed insignificantly higher intracranial hemorrhage progression risks (OR=1.22) for individuals receiving DOACs than for those receiving VK-antagonists., Conclusions: This study provides evidence on the morbidity and mortality-related outcomes associated with the pre-injury administration of VK-antagonists or DOACs in patients with TBI. We found no significant differences between VK-antagonists and DOACs on the overall morbidity (hospital and intensive care unit stays, intracranial hemorrhage, and surgical intervention frequency) and mortality outcomes in elderly patients with TBI.
- Published
- 2022
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20. Inhibition of RIPK1 by ZJU-37 promotes oligodendrocyte progenitor proliferation and remyelination via NF-κB pathway.
- Author
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Ma XR, Yang SY, Zheng SS, Yan HH, Gu HM, Wang F, Wu Y, Dong ZJ, Wang DX, Wang Y, Meng X, Sun J, Xia HG, and Zhao JW
- Abstract
Receptor interacting serine/threonine protein kinase 1 (RIPK1) activation and necroptosis have been genetically and mechanistically linked with human multiple sclerosis and neurodegenerative diseases for which demyelination is a common key pathology. Demyelination can be healed through remyelination which is mediated by new oligodendrocytes derived from the adult oligodendrocyte progenitor cells (OPCs). Unfortunately, the efficiency of remyelination declines with progressive aging partially due to the depletion of OPCs following chronic or repeated demyelination. However, to our knowledge, so far there is no drug which enhances proliferation of OPCs, and it is unknown whether inhibiting RIPK1 activity directly affect OPCs, the central player of remyelination. Using TNFα induced RIPK1-dependent necroptosis in Jurkat FADD
-/- cells as a cell death assay, we screened from 2112 FDA-approved drugs and the drug candidates of new RIPK1 inhibitors selected by ourselves, and identified ZJU-37, a small molecule modified by introducing an amide bond to Nec-1s, is a new RIPK1 kinase inhibitor with higher potency than Nec-1s which has the best reported potency. We unveil in addition to protecting myelin from demyelination and axons from degeneration, ZJU-37 exhibits a new role on promoting proliferation of OPCs and enhancing remyelination by inhibiting RIPK1 kinase activity with higher potency than Nec-1s. Mechanistically, ZJU-37 promotes proliferation of OPCs by enhancing the transcription of platelet derived growth factor receptor alpha via NF-κB pathway. This work identifies ZJU-37 as a new drug candidate which enhances remyelination by promoting proliferation of OPCs, paving the way for a potential drug to enhance myelin repair., (© 2022. The Author(s).)- Published
- 2022
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21. Restoring nuclear entry of Sirtuin 2 in oligodendrocyte progenitor cells promotes remyelination during ageing.
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Ma XR, Zhu X, Xiao Y, Gu HM, Zheng SS, Li L, Wang F, Dong ZJ, Wang DX, Wu Y, Yang C, Jiang W, Yao K, Yin Y, Zhang Y, Peng C, Gao L, Meng Z, Hu Z, Liu C, Li L, Chen HZ, Shu Y, Ju Z, and Zhao JW
- Subjects
- Aging, Animals, Cell Differentiation physiology, Cells, Cultured, Mice, Myelin Sheath, NAD, Oligodendroglia physiology, Sirtuin 2 genetics, Oligodendrocyte Precursor Cells physiology, Remyelination physiology
- Abstract
The age-dependent decline in remyelination potential of the central nervous system during ageing is associated with a declined differentiation capacity of oligodendrocyte progenitor cells (OPCs). The molecular players that can enhance OPC differentiation or rejuvenate OPCs are unclear. Here we show that, in mouse OPCs, nuclear entry of SIRT2 is impaired and NAD
+ levels are reduced during ageing. When we supplement β-nicotinamide mononucleotide (β-NMN), an NAD+ precursor, nuclear entry of SIRT2 in OPCs, OPC differentiation, and remyelination were rescued in aged animals. We show that the effects on myelination are mediated via the NAD+ -SIRT2-H3K18Ac-ID4 axis, and SIRT2 is required for rejuvenating OPCs. Our results show that SIRT2 and NAD+ levels rescue the aged OPC differentiation potential to levels comparable to young age, providing potential targets to enhance remyelination during ageing., (© 2022. The Author(s).)- Published
- 2022
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22. Early complementary acupuncture improves the clinical prognosis of traumatic brain edema: A randomized controlled trial.
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Guo ZQ, Jiang H, Huang Y, Gu HM, Wang WB, and Chen TD
- Subjects
- Acupuncture Therapy methods, Adolescent, Adult, Aged, Brain Edema etiology, Brain Injuries, Traumatic therapy, Humans, Middle Aged, Prognosis, Treatment Outcome, Young Adult, Acupuncture, Brain Edema therapy, Brain Injuries, Traumatic complications
- Abstract
Background: Traumatic brain edema occurs commonly brain injury, and most manifests as pericontusional edema of brain contusions. On the basis of evidence-based medicine, apart from recommending craniotomy and mannitol, there are few particularly effective measures to prevent and treat traumatic brain edema. It is uncertain whether an early complementary acupuncture treatment would improve long-term outcomes of patients with traumatic brain edema. The aim of this study is to assess the efficacy and the safety of early complementary acupuncture for patients with traumatic brain edema., Methods: This study is an actively accruing, single-center, single-blinded, 2-arm, randomized controlled trial. Patients with traumatic brain injury, a Glasgow Coma Scale score of 6∼12, and brain edema on computed tomography scan will be divided into 2 groups on the basis of stratified block randomization. All patients will receive conventional treatment, and the study group will undergo additional acupuncture therapy (start within 72 hours after the injury) once a day for 28 days. The primary outcome is the dichotomized Glasgow Outcome Score at 6 months and 12 months after injury, and the secondary outcomes are the Glasgow Coma Scale, the volume of traumatic brain edema, the serum levels of C-reactive protein and interleukin-6, and the Modified Barthel Index., Discussion: This study will provide data regarding the efficacy of early complementary acupuncture for traumatic brain edema. If the study yields positive results, its findings may offer insights into a valuable complementary option of acupuncture for traumatic brain edema that could provide pilot evidence for large, randomized, controlled trials.Trial registration: This trial has been published in the Chinese Clinical Trial Register, http://www.chictr.org.cn/edit.aspx?pid=141208&htm=4 (Identifier: ChiCTR2100053794, registered on December 3, 2021)., Competing Interests: All authors have no conflicts of interest to declare., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)
- Published
- 2022
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23. Loss of Hepatic Surf4 Depletes Lipid Droplets in the Adrenal Cortex but Does Not Impair Adrenal Hormone Production.
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Chang X, Zhao Y, Qin S, Wang H, Wang B, Zhai L, Liu B, Gu HM, and Zhang DW
- Abstract
The adrenal gland produces steroid hormones to play essential roles in regulating various physiological processes. Our previous studies showed that knockout of hepatic Surf4 (Surf4
LKO ) markedly reduced fasting plasma total cholesterol levels in adult mice, including low-density lipoprotein and high-density lipoprotein cholesterol. Here, we found that plasma cholesterol levels were also dramatically reduced in 4-week-old young mice and non-fasted adult mice. Circulating lipoprotein cholesterol is an important source of the substrate for the production of adrenal steroid hormones. Therefore, we investigated whether adrenal steroid hormone production was affected in Surf4LKO mice. We observed that lacking hepatic Surf4 essentially eliminated lipid droplets and significantly reduced cholesterol levels in the adrenal gland; however, plasma levels of aldosterone and corticosterone were comparable in Surf4LKO and the control mice under basal and stress conditions. Further analysis revealed that mRNA levels of genes encoding enzymes important for hormone synthesis were not altered, whereas the expression of scavenger receptor class B type I (SR-BI), low-density lipoprotein receptor (LDLR) and 3-hydroxy-3-methyl-glutaryl-CoA reductase was significantly increased in the adrenal gland of Surf4LKO mice, indicating increased de novo cholesterol biosynthesis and enhanced LDLR and SR-BI-mediated lipoprotein cholesterol uptake. We also observed that the nuclear form of SREBP2 was increased in the adrenal gland of Surf4LKO mice. Taken together, these findings indicate that the very low levels of circulating lipoprotein cholesterol in Surf4LKO mice cause a significant reduction in adrenal cholesterol levels but do not significantly affect adrenal steroid hormone production. Reduced adrenal cholesterol levels activate SREBP2 and thus increase the expression of genes involved in cholesterol biosynthesis, which increases de novo cholesterol synthesis to compensate for the loss of circulating lipoprotein-derived cholesterol in the adrenal gland of Surf4LKO mice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Chang, Zhao, Qin, Wang, Wang, Zhai, Liu, Gu and Zhang.)- Published
- 2021
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24. Neutralization of Hv1/HVCN1 With Antibody Enhances Microglia/Macrophages Myelin Clearance by Promoting Their Migration in the Brain.
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Wang F, Ma XR, Wu Y, Xu YC, Gu HM, Wang DX, Dong ZJ, Li HL, Wang LB, and Zhao JW
- Abstract
Microglia dynamically monitor the microenvironment of the central nervous system (CNS) by constantly extending and retracting their processes in physiological conditions, and microglia/macrophages rapidly migrate into lesion sites in response to injuries or diseases in the CNS. Consequently, their migration ability is fundamentally important for their proper functioning. However, the mechanisms underlying their migration have not been fully understood. We wonder whether the voltage-gated proton channel HVCN1 in microglia/macrophages in the brain plays a role in their migration. We show in this study that in physiological conditions, microglia and bone marrow derived macrophage (BMDM) express HVCN1 with the highest level among glial cells, and upregulation of HVCN1 in microglia/macrophages is presented in multiple injuries and diseases of the CNS, reflecting the overactivation of HVCN1. In parallel, myelin debris accumulation occurs in both the focal lesion and the site where neurodegeneration takes place. Importantly, both genetic deletion of the HVCN1 gene in cells in vitro and neutralization of HVCN1 with antibody in the brain in vivo promotes migration of microglia/macrophages. Furthermore, neutralization of HVCN1 with antibody in the brain in vivo promotes myelin debris clearance by microglia/macrophages. This study uncovers a new role of HVCN1 in microglia/macrophages, coupling the proton channel HVCN1 to the migration of microglia/macrophages for the first time., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Wang, Ma, Wu, Xu, Gu, Wang, Dong, Li, Wang and Zhao.)
- Published
- 2021
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25. Membrane-type I matrix metalloproteinase (MT1-MMP), lipid metabolism, and therapeutic implications.
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Xia XD, Alabi A, Wang M, Gu HM, Yang RZ, Wang GQ, and Zhang DW
- Subjects
- Adipocytes metabolism, Animals, Cell Membrane metabolism, Extracellular Matrix metabolism, Humans, Macrophages metabolism, Muscle, Smooth, Vascular metabolism, Receptors, LDL metabolism, Atherosclerosis metabolism, Lipid Metabolism, Matrix Metalloproteinase 14 metabolism, Obesity metabolism, Signal Transduction
- Abstract
Lipids exert many essential physiological functions, such as serving as a structural component of biological membranes, storing energy, and regulating cell signal transduction. Dysregulation of lipid metabolism can lead to dyslipidemia related to various human diseases, such as obesity, diabetes, and cardiovascular disease. Therefore, lipid metabolism is strictly regulated through multiple mechanisms at different levels, including the extracellular matrix. Membrane-type I matrix metalloproteinase (MT1-MMP), a zinc-dependent endopeptidase, proteolytically cleaves extracellular matrix components, and non-matrix proteins, thereby regulating many physiological and pathophysiological processes. Emerging evidence supports the vital role of MT1-MMP in lipid metabolism. For example, MT1-MMP mediates ectodomain shedding of low-density lipoprotein receptor and increases plasma low-density lipoprotein cholesterol levels and the development of atherosclerosis. It also increases the vulnerability of atherosclerotic plaque by promoting collagen cleavage. Furthermore, it can cleave the extracellular matrix of adipocytes, affecting adipogenesis and the development of obesity. Therefore, the activity of MT1-MMP is strictly regulated by multiple mechanisms, such as autocatalytic cleavage, endocytosis and exocytosis, and post-translational modifications. Here, we summarize the latest advances in MT1-MMP, mainly focusing on its role in lipid metabolism, the molecular mechanisms regulating the function and expression of MT1-MMP, and their pharmacotherapeutic implications., (© The Author(s) (2021). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, CEMCS, CAS.)
- Published
- 2021
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26. Corrigendum to "Magnesium isoglycyrrhizinate blocks fructose-induced hepatic NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder" [Eur. J. Pharmacol. 15 (2017) 809: 141-150].
- Author
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Zhao XJ, Yang YZ, Zheng YJ, Wang SC, Gu HM, Pan Y, Wang SJ, Xu HJ, and Kong LD
- Published
- 2021
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27. Regulation of PCSK9 Expression and Function: Mechanisms and Therapeutic Implications.
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Xia XD, Peng ZS, Gu HM, Wang M, Wang GQ, and Zhang DW
- Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes degradation of low-density lipoprotein receptor (LDLR) and plays a central role in regulating plasma levels of LDL cholesterol levels, lipoprotein(a) and triglyceride-rich lipoproteins, increasing the risk of cardiovascular disease. Additionally, PCSK9 promotes degradation of major histocompatibility protein class I and reduces intratumoral infiltration of cytotoxic T cells. Inhibition of PCSK9 increases expression of LDLR, thereby reducing plasma levels of lipoproteins and the risk of cardiovascular disease. PCSK9 inhibition also increases cell surface levels of major histocompatibility protein class I in cancer cells and suppresses tumor growth. Therefore, PCSK9 plays a vital role in the pathogenesis of cardiovascular disease and cancer, the top two causes of morbidity and mortality worldwide. Monoclonal anti-PCSK9 antibody-based therapy is currently the only available treatment that can effectively reduce plasma LDL-C levels and suppress tumor growth. However, high expenses limit their widespread use. PCSK9 promotes lysosomal degradation of its substrates, but the detailed molecular mechanism by which PCSK9 promotes degradation of its substrates is not completely understood, impeding the development of more cost-effective alternative strategies to inhibit PCSK9. Here, we review our current understanding of PCSK9 and focus on the regulation of its expression and functions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Xia, Peng, Gu, Wang, Wang and Zhang.)
- Published
- 2021
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28. Membrane type 1 matrix metalloproteinase promotes LDL receptor shedding and accelerates the development of atherosclerosis.
- Author
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Alabi A, Xia XD, Gu HM, Wang F, Deng SJ, Yang N, Adijiang A, Douglas DN, Kneteman NM, Xue Y, Chen L, Qin S, Wang G, and Zhang DW
- Subjects
- Animals, Apolipoproteins E genetics, Cell Line, Tumor, Cholesterol Esters metabolism, Dependovirus genetics, Female, HEK293 Cells, Hep G2 Cells, Humans, Male, Matrix Metalloproteinase 14 genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Apolipoprotein B-100 blood, Apolipoproteins E blood, Atherosclerosis pathology, Lipoproteins, LDL blood, Matrix Metalloproteinase 14 metabolism, Receptors, LDL metabolism
- Abstract
Plasma low-density lipoprotein (LDL) is primarily cleared by LDL receptor (LDLR). LDLR can be proteolytically cleaved to release its soluble ectodomain (sLDLR) into extracellular milieu. However, the proteinase responsible for LDLR cleavage is unknown. Here we report that membrane type 1-matrix metalloproteinase (MT1-MMP) co-immunoprecipitates and co-localizes with LDLR and promotes LDLR cleavage. Plasma sLDLR and cholesterol levels are reduced while hepatic LDLR is increased in mice lacking hepatic MT1-MMP. Opposite effects are observed when MT1-MMP is overexpressed. MT1-MMP overexpression significantly increases atherosclerotic lesions, while MT1-MMP knockdown significantly reduces cholesteryl ester accumulation in the aortas of apolipoprotein E (apoE) knockout mice. Furthermore, sLDLR is associated with apoB and apoE-containing lipoproteins in mouse and human plasma. Plasma levels of sLDLR are significantly increased in subjects with high plasma LDL cholesterol levels. Thus, we demonstrate that MT1-MMP promotes ectodomain shedding of hepatic LDLR, thereby regulating plasma cholesterol levels and the development of atherosclerosis.
- Published
- 2021
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29. Atherosclerosis-associated hepatic secretion of VLDL but not PCSK9 is dependent on cargo receptor protein Surf4.
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Wang B, Shen Y, Zhai L, Xia X, Gu HM, Wang M, Zhao Y, Chang X, Alabi A, Xing S, Deng S, Liu B, Wang G, Qin S, and Zhang DW
- Subjects
- Animals, Cells, Cultured, Membrane Proteins deficiency, Mice, Mice, Inbred C57BL, Mice, Knockout, Proprotein Convertase 9 deficiency, Proprotein Convertase 9 metabolism, Receptors, LDL deficiency, Receptors, LDL metabolism, Atherosclerosis metabolism, Lipoproteins, VLDL metabolism, Membrane Proteins metabolism
- Abstract
Plasma LDL is produced from catabolism of VLDL and cleared from circulation mainly via the hepatic LDL receptor (LDLR). Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDLR degradation, increasing plasma LDL-C levels. Circulating PCSK9 is mainly secreted by the liver, whereas VLDL is exclusively secreted by hepatocytes. However, the mechanism regulating their secretion is not completely understood. Surfeit 4 (Surf4) is a cargo receptor localized in the ER membrane. It recruits cargos into coat protein complex II vesicles to facilitate their secretion. Here, we investigated the role of Surf4 in VLDL and PCSK9 secretion. We generated Surf4 liver-specific knockout mice and found that knockout of Surf4 did not affect PCSK9 secretion, whereas it significantly reduced plasma levels of cholesterol, triglyceride, and lipid-binding protein apolipoprotein B (apoB). In cultured human hepatocytes, Surf4 coimmunoprecipitated and colocalized with apolipoprotein B100, and Surf4 silencing reduced secretion of apolipoprotein B100. Furthermore, knockdown of Surf4 in LDLR knockout (Ldlr
-/- ) mice significantly reduced triglyceride secretion, plasma levels of apoB and non-HDL-C, and the development of atherosclerosis. However, Surf4 liver-specific knockout mice and Surf4 knockdown in Ldlr-/- mice displayed similar levels of liver lipids and plasma alanine aminotransferase activity as control mice, indicating that inhibition of Surf4 does not cause notable liver damage. Expression of stearoyl-CoA desaturase-1 was also reduced in the liver of these mice, suggesting a reduction in de novo lipogenesis. In summary, hepatic deficiency of Surf4 reduced VLDL secretion and the development of atherosclerosis but did not cause significant hepatic lipid accumulation or liver damage., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2021
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30. The role of the C-terminal domain of PCSK9 and SEC24 isoforms in PCSK9 secretion.
- Author
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Deng SJ, Shen Y, Gu HM, Guo S, Wu SR, and Zhang DW
- Subjects
- HEK293 Cells, Humans, Mutagenesis, Site-Directed, Proprotein Convertase 9 genetics, Proprotein Convertase 9 metabolism, Protein Domains genetics, Vesicular Transport Proteins metabolism
- Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a secretory protein that promotes low-density lipoprotein receptor (LDLR) degradation and thereby regulating plasma levels of LDL cholesterol. Previous studies have revealed the role of the C-terminal domain (CTD) of PCSK9 in its secretion, however, how CTD regulates PCSK9 secretion is not completely understood. Additionally, SEC24A, the cargo adaptor protein of the coat protein complex II, has been implicated in the secretion of mouse PCSK9. Here, we investigated how CTD and SEC24 regulated PCSK9 secretion in humans. We found that mutant PCSK9
1-528 , in which amino acids from 529 to the end (amino acid 692) were deleted, was maturated and secreted from cells as effectively as the wild-type protein. On the other hand, lacking amino acids 454 to 692 in mutant PCSK91-453 significantly reduced its maturation and secretion, but to a lesser extent when compared to mutants PCSK91-446 , PCSK91-445 and PCSK91-444 , that all markedly impaired PCSK9 maturation. However, mutant PCSK91-444 virtually eliminated PCSK9 secretion while PCSK91-446 and PCSK91-445 could still be adequately detected in culture medium. Interestingly, mutation of Pro445 to other amino acid residues considerably impaired the secretion of mutant PCSK91-445 but not the full-length protein. We also found that natural variants in CTD including S462P, S465L, E482G, R495Q and A522T impaired PCSK9 secretion. Further, the knockdown of SEC24A, SEC24B, SEC24C but not SEC24D reduced secretion of the full-length PCSK9 but not mutant PCSK91-446 . Therefore, SEC24A, SEC24B, and SEC24C facilitate endogenous PCSK9 secretion from cultured human hepatocytes, that are most likely mediated by the CTD of PCSK9. Our studies also indicate that the CTD of PCSK9 may allosterically and independently modulate the stability of the hinge region. Collectively, these data revealed that the CTD of PCSK9 and the hinge region play a critical role in PCSK9 maturation and secretion., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2020
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31. Surf4 regulates expression of proprotein convertase subtilisin/kexin type 9 (PCSK9) but is not required for PCSK9 secretion in cultured human hepatocytes.
- Author
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Shen Y, Wang B, Deng S, Zhai L, Gu HM, Alabi A, Xia X, Zhao Y, Chang X, Qin S, and Zhang DW
- Subjects
- Gene Knockdown Techniques, HEK293 Cells, Hep G2 Cells, Humans, Membrane Proteins genetics, RNA, Small Interfering metabolism, Membrane Proteins metabolism, Proprotein Convertase 9 metabolism
- Published
- 2020
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32. Proprotein Convertase Subtilisin/Kexin-Type 9 and Lipid Metabolism.
- Author
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Guo S, Xia XD, Gu HM, and Zhang DW
- Subjects
- Humans, Proprotein Convertase 9 chemistry, Receptors, LDL metabolism, Subtilisin chemistry, Lipid Metabolism, Proprotein Convertase 9 metabolism, Subtilisin metabolism
- Abstract
Plasma levels of cholesterol, especially low-density lipoprotein cholesterol (LDL-C), are positively correlated with the risk of cardiovascular disease. Buildup of LDL in the intima promotes the formation of foam cells and consequently initiates atherosclerosis, one of the main underlying causes of cardiovascular disease. Hepatic LDL receptor (LDLR) is mainly responsible for the clearance of plasma LDL. Mutations in LDLR cause familiar hypercholesterolemia and increase the risk of premature coronary heart disease. Proprotein convertase subtilisin/kexin-type 9 (PCSK9) promotes LDLR degradation and thereby plays a critical role in the regulation of plasma cholesterol metabolism. PCSK9 can bind to LDLR and reroute the receptor to lysosomes for degradation, increasing both circulating LDL-C levels and the risk of cardiovascular disease. PCSK9 is mainly regulated by sterol response element binding protein 2 (SREBP2) at the transcriptional level. Furthermore, many proteins have been identified as interacting with PCSK9, regulating plasma cholesterol levels. Pharmacotherapeutic inhibition of PCSK9 dramatically reduces plasma levels of LDL cholesterol and significantly reduces cardiovascular events. In this article, we summarize the latest advances in PCSK9, mainly focusing on the structure, function, and regulation of the protein, the underlying molecular mechanisms, and its pharmacotherapeutic applications.
- Published
- 2020
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33. [Effect of processing excipient suet oil on formation and absorption of baohuoside Ⅰ-bile salt self-assembled micelles].
- Author
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Gu HM, Sun E, Li J, Hou J, and Jia XB
- Subjects
- Animals, Caco-2 Cells, Epimedium chemistry, Humans, Intestinal Absorption, Rats, Drugs, Chinese Herbal pharmacokinetics, Excipients chemistry, Flavonoids pharmacokinetics, Micelles, Oils chemistry
- Abstract
The fried method with suet oil,which can strengthen the effect of Epimedium in warming kidney and enhancing Yang,has been widely used in the processing of Epimedium in traditional Chinese medicine. Based on the formation mechanism of Epimedium flavonoids self-assembled micelles in vivo,the synergistic mechanism of processing excipient suet oil was investigated in this paper from the perspective of pharmaceutics. Baohuoside Ⅰ,as representative component of processed Epimedium,was selected as model drug.Average size and zeta potential were measured and the morphology of micelles was observed under transmission electron microscopy. Caco-2 monolayer cell model,rat intestinal perfusion model and in vivo serum drug concentration method were established to investigate the effect of suet oil on the formation and absorption of the baohuosideⅠ bile salt self-assembled micelles. Baohuoside Ⅰ can form selfassembled micelles under the action of sodium deoxycholate. While,adding suet oil into the baohuoside Ⅰ-bile salt micelles( BSDOC) can make it form a more stable system with a smaller average size,higher Zeta potential,lower polydispersity index( PDI) value,significantly improved encapsulation efficiency and drug loading,indicating that suet oil could significantly improve the micelle formation in vivo. In addition,the permeability coefficient of baohuoside Ⅰ in Caco-2 monolayer cells and the four intestinal organs( duodenum,jejunum,ileum and colon) was increased and the oral bioavailability was also improved after adding the suet oil to BS-DOC.All the results demonstrated that the suet oil can promote the formation and absorption of baohuoside Ⅰ self-assembled micelles,so as to enhance its synergistic effects.
- Published
- 2019
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34. [Mechanism of flavonoid components in Astragali Radix in inhibiting tumor growth and immunoregulation in C57BL/6 tumor bearing mice based on "invigorating Qi for consolidation of exterior"].
- Author
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Yang B, Yu GH, Li MY, Gu HM, Chen YP, Feng L, and Jia XB
- Subjects
- Animals, Endoplasmic Reticulum Chaperone BiP, Mice, Mice, Inbred C57BL, Xenograft Model Antitumor Assays, Astragalus Plant chemistry, Carcinoma, Lewis Lung drug therapy, Drugs, Chinese Herbal therapeutic use, Flavonoids therapeutic use, Qi
- Abstract
Traditional Chinese medicine believes that the occurrence and development of tumors is related to the body's Qi deficiency. " Invigorating Qi for consolidation of exterior" has became an effective way to treat tumors by traditional Chinese medicine. This study is based on the " invigorating Qi for consolidation of exterior" to explore the effect of flavonoid components in Qi-invigorating herbs Astragali Radix( AR) on the growth and immune function of mouse Lewis lung cancer xenografts,and further explore its mechanism of action. In the present study,high performance liquid chromatography was performed to analyze the flavonoid components in AR.The Lewis lung cancer model of C57 BL/6 mice was constructed,and the tumor volume of mice was determined by Visual Sonics Vevo2100 high frequency color ultrasound. The levels of IL~(-1)7 and RORγt in serum and tumor tissues were detected by ELISA and immunohistochemistry. The expression of IRE~(-1)/XBP~(-1) pathway-related proteins in tumor tissues was detected by Western blot. The results revealed that treatment of 5 and 10 g·kg~(-1)·d~(-1) of flavonoid components in AR significantly inhibited tumor growth of C57 BL/6 tumorbearing mice. The inhibition rates at the dose of 5 and 10 g·kg~(-1)·d~(-1) of flavonoid components in AR were( 29. 5±4. 4) % and( 43. 4±5. 2) %,respectively. The expression of IL~(-1)7 and RORγt in serum and tumor tissues of Lewis lung cancer mice were decreased,and the spleen index and thymus index were significantly enhanced by the flavonoid components in AR. Flavonoid components in AR could decrease the expression of X-box binding protein 1( XBP1),inositol-requiring enzyme( IRE1) and glucose regulated protein 78 k D( GRP78),and increase the expression of C/EBP homologous protein( CHOP),and the high-dose group is better,suggesting that the anti-lung cancer effect of flavonoid components in AR is related to the regulation of XBP1 mediated ERs. This study provides new evidence that the flavonoid components in AR could inhibit the tumor growth of C57 BL/6 tumor-bearing mice by regulating the body's immune function through " invigorating Qi for consolidation of exterior".
- Published
- 2019
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35. Efficacy and safety of magnesium isoglycyrrhizinate injection in patients with acute drug-induced liver injury: A phase II trial.
- Author
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Wang Y, Wang Z, Gao M, Zhong H, Chen C, Yao Y, Zhang Z, Zhang X, Li F, Zhang J, Gu HM, Chen Y, Tang J, Zhong W, Zeng M, and Mao Y
- Subjects
- Adult, Chemical and Drug Induced Liver Injury blood, China, Double-Blind Method, Female, Humans, Injections, Intravenous, Liver drug effects, Liver pathology, Logistic Models, Male, Middle Aged, Saponins adverse effects, Triterpenes adverse effects, Young Adult, Alanine Transaminase blood, Chemical and Drug Induced Liver Injury drug therapy, Saponins administration & dosage, Triterpenes administration & dosage
- Abstract
Background: Drug-induced liver injury (DILI) is the most common reason for a drug to be withdrawn from the market. Apart from stopping the offending drug, no regimens are available for treating idiosyncratic DILI in clinical practice., Methods: We carried out a randomized, double-blind, multidoses, active drug controlled, multicentre phase II trial to assess the safety and efficacy of the study drug, magnesium isoglycyrrhizinate (MgIG), as compared to tiopronin, a standard therapy for DILI in China. The primary outcome was the proportion of alanine aminotransferase (ALT) normalization at week 4 after study drug administration. Logistic regression was used to examine the odds of ALT normalization between low dose (Group A) and high dose (Group B) vs active control (Group C)., Results: One hundred and seventy-four eligible subjects were randomized and enrolled into three groups: 59 in group A, 56 in group B and 59 in group C. It was shown that group A and group B lowered ALT level even at early stage of study drug administration; when compared with Group C (61.02%), the proportions of ALT normalization at week 4 were significantly greater in Group A (84.75%, P = .0029) and Group B (85.71%, P = .0037) respectively. The results from the univariate logistic model showed that the odds of ALT normalized among subjects in Group A were about 3.6 times greater (OR = 3.55, 95% CI: 1.47-8.57, P = .0049) than subjects in Group C. Similar effect was observed among subjects in Group B (OR = 3.83, 95% CI: 1.54-9.55, P = .0039)., Conclusions: This trial provided preliminary evidence that MgIG is an effective and safe treatment for patients with acute DILI., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2019
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36. Magnesium isoglycyrrhizinate ameliorates fructose-induced podocyte apoptosis through downregulation of miR-193a to increase WT1.
- Author
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Li TS, Chen L, Wang SC, Yang YZ, Xu HJ, Gu HM, Zhao XJ, Dong P, Pan Y, Shang ZQ, Zhang XQ, and Kong LD
- Subjects
- Animals, Apoptosis drug effects, Cell Line, Dose-Response Relationship, Drug, Drugs, Chinese Herbal pharmacology, Humans, Male, MicroRNAs antagonists & inhibitors, Podocytes drug effects, Rats, Rats, Sprague-Dawley, Apoptosis physiology, Fructose toxicity, MicroRNAs metabolism, Podocytes metabolism, Saponins pharmacology, Triterpenes pharmacology, WT1 Proteins metabolism
- Abstract
High fructose intake is a risk of glomerular podocyte dysfunction. Podocyte apoptosis has emerged as a major cause of podocyte loss, exacerbating proteinuria. Magnesium isoglycyrrhizinate (MgIG) is usually used as a hepatoprotective agent in clinic. Liver and kidney injury often occurs in human diseases. Recent report shows that MgIG improves kidney function. In this study, we found that MgIG significantly alleviated kidney dysfunction, proteinuria and podocyte injury in fructose-fed rats. It also restored fructose-induced podocyte apoptosis in rat glomeruli and cultured differentiated podocytes. Of note, high-expression of miR-193a, downregulation of Wilms' tumor protein (WT1) and RelA, as well as upregulation of C-Maf inducing protein (C-mip) were observed in these animal and cell models. The data from the transfection of miR-193a mimic, miR-193a inhibitor, WT1 siRNA or LV5-WT1 in cultured differentiated podocytes showed that fructose increased miR-193a to down-regulate WT1, and subsequently activated C-mip to suppress RelA, causing podocyte apoptosis. These disturbances were significantly attenuated by MgIG. Taken together, these results provide the first evidence that MgIG restrains fructose-induced podocyte apoptosis at least partly through inhibiting miR-193a to upregulate WT1, supporting the application of MgIG with a novel mechanism-of-action against podocyte apoptosis associated with fructose-induced kidney dysfunction., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
37. Magnesium isoglycyrrhizinate ameliorates high fructose-induced liver fibrosis in rat by increasing miR-375-3p to suppress JAK2/STAT3 pathway and TGF-β1/Smad signaling.
- Author
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Yang YZ, Zhao XJ, Xu HJ, Wang SC, Pan Y, Wang SJ, Xu Q, Jiao RQ, Gu HM, and Kong LD
- Subjects
- Animals, Cell Line, Epithelial-Mesenchymal Transition drug effects, Fructose, Janus Kinase 2 metabolism, Liver Cirrhosis chemically induced, Male, Rats, Sprague-Dawley, STAT3 Transcription Factor metabolism, Saponins pharmacology, Smad Proteins, Receptor-Regulated metabolism, Transforming Growth Factor beta1 metabolism, Triterpenes pharmacology, Liver Cirrhosis drug therapy, MicroRNAs metabolism, Saponins therapeutic use, Signal Transduction drug effects, Triterpenes therapeutic use
- Abstract
Increasing evidence has demonstrated that excessive fructose intake induces liver fibrosis. Epithelial-mesenchymal transition (EMT) driven by transforming growth factor-β1 (TGF-β1)/mothers against decapentaplegic homolog (Smad) signaling activation promotes the occurrence and development of liver fibrosis. Magnesium isoglycyrrhizinate is clinically used as a hepatoprotective agent to treat liver fibrosis, but its underlying molecular mechanism has not been identified. Using a rat model, we found that high fructose intake reduced microRNA (miR)-375-3p expression and activated the janus-activating kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) cascade and TGF-β1/Smad signaling, which is consistent with the EMT and liver fibrosis. To further verify these observations, BRL-3A cells and/or primary rat hepatocytes were exposed to high fructose and/or transfected with a miR-375-3p mimic or inhibitor or treated with a JAK2 inhibitor, and we found that the low expression of miR-375-3p could induce the JAK2/STAT3 pathway to activate TGF-β1/Smad signaling and promote the EMT. Magnesium isoglycyrrhizinate was found to ameliorate high fructose-induced EMT and liver fibrosis in rats. More importantly, magnesium isoglycyrrhizinate increased miR-375-3p expression to suppress the JAK2/STAT3 pathway and TGF-β1/Smad signaling in these animal and cell models. This study provides evidence showing that magnesium isoglycyrrhizinate attenuates liver fibrosis associated with a high fructose diet.
- Published
- 2019
- Full Text
- View/download PDF
38. [Impact of subchronic exposure to low-dose nano-nickel oxide on the reproductive function and offspring of male rats].
- Author
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Fan XJ, Yu FB, Gu HM, You LM, DU ZH, Gao JX, and Niu YY
- Subjects
- Animals, Dose-Response Relationship, Drug, Epididymis drug effects, Female, Male, Organ Size, Pregnancy, Random Allocation, Rats, Rats, Sprague-Dawley, Sperm Motility, Spermatozoa pathology, Testis drug effects, Toxicity Tests, Subchronic, Epididymis physiopathology, Metal Nanoparticles toxicity, Nickel toxicity, Prenatal Exposure Delayed Effects pathology, Testis physiopathology
- Abstract
Objective: To investigate the influence of subchronic exposure to low-dose subchronic nano-nickel oxide (NNO) on the reproductive function of male rats and embryonic development of the pregnant rats., Methods: Fifty normal healthy male SD rats weighing 180-220 g were randomly divided into five groups of equal number, negative control, 4 mg/ml micro-nickel oxide (MNO), and 0.16, 0.8 and 4 mg/ml NNO, those of the latter four groups exposed to MNO or NNO by non-contact intratracheal instillation once every 3 days for 60 days, and then all mated with normal adult female rats in the ratio of 1∶2. After the female animals were confirmed to be pregnant, the males were sacrificed and the weights of the body, testis and epididymis obtained, followed by calculation of the visceral coefficients, determination of epididymal sperm concentration and viability and the nickel contents in the blood and semen by atomic fluorescence spectrometry. The female rats were killed on the 20th day of gestation for counting of the implanted fertilized eggs and live, dead and resorbed fetuses., Results: After 60 days of exposure, the rats of the NNO groups showed no statistically significant differences from those of the negative control and MNO groups in the weights of the body, testis and epididymis or visceral coefficients. Compared with the negative control group, the animals of the 0.8 and 4 mg/ml NNO groups exhibited markedly decreased sperm concentration ([9.36 ± 0.98] vs [7.49 ± 1.46] and [6.30 ± 1.36] ×10⁶/ml, P < 0.05) and viable sperm ([85.35 ± 9.16]% vs [68.26 ± 16.63]% and [65.88 ± 14.68] %, P < 0.05), increased morphologically abnormal sperm ([8.30 ± 2.47]% vs [13.99 ± 4.87]% and [15.38 ± 8.86] %, P < 0.05), and elevated rate of dead and resorbed fetuses (1.18% vs 6.89% and 7.37%, P < 0.05), blood nickel content ([0.13 ± 0.16] vs [0.52 ± 0.34] and [0.82 ± 0.44] mg/L, P < 0.05) and semen nickel content ([0.08 ± 0.13] vs [0.35 ± 0.23] and [0.63 ± 0.61] mg/L, P < 0.05). The nickel level in the semen was correlated significantly with that in the blood (r = 0.912, P <0.01), negatively with the rate of viable sperm (r = -0.879, P <0.01) and positively with the percentage of morphologically abnormal sperm (r = -0.898, P <0.01)., Conclusions: Sixty-day exposure to nano-nickel oxide at 0.8 and 4 mg/ml can produce reproductive toxicity in male rats and result in fetal abnormality in the females, while that at 0.16 mg/ml has no significant toxic effect on the reproductive function of the males.
- Published
- 2019
39. Identification of amino acid residues in the ligand binding repeats of LDL receptor important for PCSK9 binding.
- Author
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Deng SJ, Alabi A, Gu HM, Adijiang A, Qin S, and Zhang DW
- Subjects
- HEK293 Cells, Humans, Ligands, Lipoproteins, LDL metabolism, Mutation, Protein Binding, Receptors, LDL genetics, Proprotein Convertase 9 metabolism, Receptors, LDL chemistry, Receptors, LDL metabolism, Repetitive Sequences, Amino Acid
- Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDL receptor (LDLR) degradation, increasing plasma levels of LDL cholesterol and the risk of cardiovascular disease. We have previously shown that, in addition to the epidermal growth factor precursor homology repeat-A of LDLR, at least three ligand-binding repeats (LRs) of LDLR are required for PCSK9-promoted LDLR degradation. However, how exactly the LRs contribute to PCSK9's action on the receptor is not completely understood. Here, we found that substitution of Asp at position 172 in the linker between the LR4 and LR5 of full-length LDLR with Asn (D172N) reduced PCSK9 binding at pH 7.4 (mimic cell surface), but not at pH 6.0 (mimic endosomal environment). On the other hand, mutation of Asp at position 203 in the LR5 of full-length LDLR to Asn (D203N) significantly reduced PCSK9 binding at both pH 7.4 and pH 6.0. D203N also significantly reduced the ability of LDLR to mediate cellular LDL uptake, whereas D172N had no detectable effect. These findings indicate that amino acid residues in the LRs of LDLR play an important role in PCSK9 binding to the receptor., (Copyright © 2019 Deng et al. Published by The American Society for Biochemistry and Molecular Biology, Inc.)
- Published
- 2019
- Full Text
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40. Therapeutic effects of bee venom and its major component, melittin, on atopic dermatitis in vivo and in vitro.
- Author
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An HJ, Kim JY, Kim WH, Gwon MG, Gu HM, Jeon MJ, Han SM, Pak SC, Lee CK, Park IS, and Park KK
- Subjects
- Animals, Cell Differentiation drug effects, Cell Survival drug effects, Cells, Cultured, Dermatitis, Atopic pathology, Disease Models, Animal, Dose-Response Relationship, Drug, Female, Humans, In Vitro Techniques, Mice, Mice, Inbred BALB C, Structure-Activity Relationship, Bee Venoms pharmacology, Dermatitis, Atopic drug therapy, Melitten pharmacology
- Abstract
Background and Purpose: Atopic dermatitis (AD) is a multifactorial skin condition with complex interactions of innate and adaptive immune responses. There are several existing therapies for AD, including topical glucocorticosteroids, emollients, phototherapies, calcineurin inhibitors and immunosuppressants, such as cyclosporine A. Although these therapies reduce inflammation, they also cause serious side effects. Therefore, it is necessary to develop new therapeutic approaches for AD treatment without side effects. There are several studies on natural materials or toxins, such as herbs, ginseng extract and snake venom, for AD treatment. However, treatment of AD with bee venom and its major component, melittin has rarely been studied., Experimental Approach: Effects of bee venom and melittin were studied in a model of AD in vivo induced by 1-chloro-2,4-dinitrobenzene (DNCB) in female Balb/c mice and in cultures of human keratinocytes, stimulated by TNF-α/IFN-γ. The potential pharmacological effects of bee venom and melittin on these in vivo and in vitro AD-like skin disease models were studied., Key Results: Bee venom and melittin exhibited potent anti-atopic activities, shown by decreased AD-like skin lesions, induced by DNCB in mice. In vitro studies using TNF-α/IFN-γ-stimulated human keratinocytes showed that bee venom and melittin inhibited the increased expression of chemokines, such as CCL17 and CCL22, and pro-inflammatory cytokines, including IL-1β, IL-6 and IFN-γ, through the blockade of the NF-κB and STAT signalling pathways., Conclusions and Implications: Our results suggest that bee venom and melittin would be suitable for epicutaneous application, as topical administration is often appropriate for the treatment of AD., (© 2018 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)
- Published
- 2018
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41. [Cerebral hemorrhage after thrombolysis in anacute myocardial infarction patient complicating thrombus in aortic root].
- Author
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Gu HM, Chen C, and Sheng HZ
- Published
- 2018
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42. Dataset on assessment of magnesium isoglycyrrhizinate injection for dairy diet and body weight in fructose-induced metabolic syndrome of rats.
- Author
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Zhao XJ, Yang YZ, Zheng YJ, Wang SC, Gu HM, Pan Y, Wang SJ, Xu HJ, and Kong LD
- Abstract
The data presented herein are related to the research article entitled "Magnesium isoglycyrrhizinate blocks fructose-induced hepatic NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder" (Zhao et al., 2017) [1]. This article describes the effects of magnesium isoglycyrrhizinate on 24-h food or water intake in fructose-fed rats at 15-week. In addition, this article expands the effect of magnesium isoglycyrrhizinate on the animal body weight change during 1-17 week. The field dataset is made publicly available to enable critical or extended analyzes.
- Published
- 2018
- Full Text
- View/download PDF
43. [Responses of main characters of root system to salt stress among cotton varieties with diffe-rent salt tolerance].
- Author
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Wang QH, Han W, Hou YY, Feng L, Ye ZP, Gu HM, and Chen BL
- Subjects
- Plant Leaves, Sodium, Soil, Gossypium physiology, Plant Roots, Salt Tolerance
- Abstract
A pot experiment was carried out to test the effects of salt levels on root morphology as well as the relationship between root morphology and salt tolerance with four cotton cultivars (salt-sensitive cultivar CCRI45, weak salt-resistance cultivar XLZ17, moderate salt-resistance cultivar XLZ13 and salt-resistance cultivar CCRI35). Results showed that dry mass and K
+ /Na+ ratio of cotton root and leaf were significantly reduced by salt stress. Dry mass of root and leaf and K+ /Na+ ratio of root of cultivars XLZ13 and CCRI35 were 69.3%-104.4%, 24.8%-45.3% and 25.0%-45.8% higher than those of cultivar CCRI45, respectively. Root development was significantly restrained by salt stress. Total root length, total root surface area and total root volume of cultivars XLZ13 and CCRI35 were 15.2%-85.8%, 12.0%-68.5% and 31.7%-217.8% higher than those of cultivar CCRI45, respectively. Furthermore, the length of fine and middle roots, root surface area and root volume of cultivars XLZ13 and CCRI35 in 0-10 cm soil layer were 27.2%-73.9%, 39.6%-74.3% and 99.0%-309.7% higher than those of cultivar CCRI45, respectively. Results from principal component analysis showed that the variations of specific root length, root length ratio at 0-10 cm soil layer and fine root length ratio at 0-10 cm soil layer among cultivars was significant. Specific root length, root length ratio at 0-10 cm soil layer and fine root length ratio at 0-10 cm soil layer were the main root characters to distinguish different salt tolerant cotton cultivars. Results from the stepwise regression analysis showed that specific root length, coarse root length, coarse root area, and coarse root volume at 0-10 cm and 10-20 cm soil layers, as well as fine root area and middle root ratio at 0-10 cm soil layer were sensitive to salt. Salt tolerant cultivar adapted to salt stress through increasing root length ratio, fine length ratio, and specific root length.- Published
- 2018
- Full Text
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44. Magnesium isoglycyrrhizinate blocks fructose-induced hepatic NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder.
- Author
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Zhao XJ, Yang YZ, Zheng YJ, Wang SC, Gu HM, Pan Y, Wang SJ, Xu HJ, and Kong LD
- Subjects
- Animals, Down-Regulation drug effects, Hep G2 Cells, Humans, Liver metabolism, Liver pathology, Male, PPAR alpha metabolism, Rats, Rats, Sprague-Dawley, Signal Transduction drug effects, Sterol Regulatory Element Binding Protein 1 metabolism, Fructose adverse effects, Inflammasomes metabolism, Lipid Metabolism drug effects, Liver drug effects, NF-kappa B metabolism, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Saponins pharmacology, Triterpenes pharmacology
- Abstract
Magnesium isoglycyrrhizinate as a hepatoprotective agent possesses immune modulation and anti-inflammation, and treats liver diseases. But its effects on immunological-inflammatory and metabolic profiles for metabolic syndrome with liver injury and underlying potential mechanisms are not fully understood. In this study, magnesium isoglycyrrhizinate alleviated liver inflammation and lipid accumulation in fructose-fed rats with metabolic syndrome. It also suppressed hepatic inflammatory signaling activation by reducing protein levels of phosphorylation of nuclear factor-kappa B p65 (p-NF-κB p65), inhibitor of nuclear factor kappa-B kinase α/β (p-IKKα/β) and inhibitor of NF-κB α (p-IκBα) as well as nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC) and Caspase-1 in rats, being consistent with its reduction of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and IL-6 levels. Furthermore, magnesium isoglycyrrhizinate modulated lipid metabolism-related genes characterized by up-regulating peroxisome proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase-1 (CPT-1), and down-regulating sensor for fatty acids to control-1 (SREBP-1) and stearoyl-CoA desaturase 1 (SCD-1) in the liver of fructose-fed rats, resulting in the reduction of triglyceride and total cholesterol levels. These effective actions were further confirmed in fructose-exposed BRL-3A and HepG2 cells. The molecular mechanisms underpinning these observations suggest that magnesium isoglycyrrhizinate may inhibit NF-κB/NLRP3 inflammasome activation to reduce immunological-inflammatory response, which in turn may prevent liver lipid metabolic disorder and accumulation under high fructose condition. Thus, blockade of NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder by magnesium isoglycyrrhizinate may be the potential therapeutic approach for improving fructose-induced liver injury with metabolic syndrome in clinic., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
- Full Text
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45. The association between interleukin-19 concentration and diabetic nephropathy.
- Author
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Li L, Jiang XG, Hu JY, Yu ZQ, Xu JY, Liu F, Zhao GC, Zhang L, Gu HM, Zhang SJ, and Meng J
- Subjects
- Biomarkers blood, China epidemiology, Diabetic Nephropathies epidemiology, Female, Humans, Male, Middle Aged, Prevalence, Reproducibility of Results, Risk Factors, Sensitivity and Specificity, Diabetic Nephropathies blood, Diabetic Nephropathies diagnosis, Interleukins blood
- Abstract
Background: Interleukin-19 (IL-19) is a newly discovered cytokine belonging to the Interleukin-10(IL-10) family. IL-19 have indispensable functions in many inflammatory processes and also can induce the angiogenic potential of endothelial cells. The purpose of present study was to investigate the relation of serum interleukin-19 (IL-19) levels with diabetic nephropathy (DN)., Methods: Two hundred study groups of patients with type 2 diabetes mellitus (T2DM) (109 males and 91 females) were recruited, included normoalbuminuria(n = 102), microalbuminuria(n = 72) and macroalbuminuria(n = 26) . The 50 healthy blood donors were enrolled for the control group. All subjects were assessed for: IL-19, High-sensitivity C-reactive protein (Hs-CRP), Cystatin C, urinary albumin excretion rate (UAE) and glycosylated hemoglobin A1c(HbA1c)., Results: The serum IL-19 levels in DN patients were found to be significantly higher compared to controls. IL-19 levels were significantly positively correlated with Hs-CRP, Cystatin C, UAE and HbA1c(r = 0.623, 0.611,0.591 and 0.526 respectively, P < 0.01). Multivariable logistic regression analysis showed IL-19 levels (P = 0.01) were found to be independently associated with patients with DN., Conclusions: IL-19 is significantly positive correlated with UAE and Cystatin C. IL-19 may play an important role that contributes to the progression of diabetic nephropathy.
- Published
- 2017
- Full Text
- View/download PDF
46. Comparison between perfusion computed tomography and dynamic contrast-enhanced magnetic resonance imaging in assessing glioblastoma microvasculature.
- Author
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Jia ZZ, Shi W, Shi JL, Shen DD, Gu HM, and Zhou XJ
- Subjects
- Adult, Aged, Brain blood supply, Brain diagnostic imaging, Brain pathology, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Female, Glioblastoma diagnostic imaging, Glioblastoma pathology, Humans, Male, Microvessels pathology, Middle Aged, Prospective Studies, Brain Neoplasms blood supply, Contrast Media, Glioblastoma blood supply, Image Enhancement methods, Magnetic Resonance Imaging methods, Microvessels diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
Purpose: Perfusion computed tomography (PCT) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) provide independent measurements of biomarkers related to tumor perfusion. The aim of this study was to compare the two techniques in assessing glioblastoma microvasculature., Materials and Methods: Twenty-five patients diagnosed with glioblastoma (14 males and 11 females; 51±11years old, ranging from 33 to 70 years) were includede in this prospective study. All patients underwent both PCT and DCE-MRI. Imaging was performed on a 256-slice CT scanner and a 3-T MRI system. PCT yielded permeability surface-area product (PS) using deconvolution physiological models; meanwhile, DCE-MRI determined volume transfer constant (K
trans ) using the Tofts-Kermode compartment model. All cases were submitted to surgical intervention, and CD105-microvascular density (CD105-MVD) was measured in each glioblastoma specimen. Then, Spearman's correlation coefficients and Bland-Altman plots were obtained for PS, Ktrans and CD105-MVD. P<0.05 was considered statistically significant., Results: Tumor PS and Ktrans values were correlated with CD105-MVD (r=0.644, P<0.001; r=0.683, P<0.001). In addition, PS was correlated with Ktrans in glioblastoma (r=0.931, P<0.001). Finally, Bland-Altman plots showed no significant differences between PS and Ktrans (P=0.063)., Conclusion: PCT and DCE-MRI measurements of glioblastoma perfusion biomarkers have similar results, suggesting that both techniques may have comparable utility. Therefore, PCT may serve as an alternative modality to DCE-MRI for the in vivo evaluation of glioblastoma microvasculature., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)- Published
- 2017
- Full Text
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47. Interleukin-19 and angiopoietin-2 can enhance angiogenesis of diabetic complications.
- Author
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Li L, Yu ZH, Qian L, Xu JY, Liu F, Zhao GC, Zhang L, Gu HM, Zhang SJ, and Meng J
- Subjects
- Aged, Case-Control Studies, Cohort Studies, Diabetes Complications blood, Female, Humans, Male, Middle Aged, Angiopoietin-2 blood, Diabetes Mellitus, Type 2 blood, Diabetes Mellitus, Type 2 complications, Diabetic Angiopathies blood, Interleukins blood, Neovascularization, Pathologic blood
- Abstract
This study was to investigate the role of interleukin-19 (IL-19) and angiopoietin-2 (Ang-2) in angiogenesis of type 2 diabetes (T2DM). In 240 patients with T2DM, IL-19 and Ang-2 levels were higher, IL-19 was positively correlated with Ang-2. IL-19 and Ang-2 might be involved in angiogenesis of T2DM complications., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
- Full Text
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48. Identification of an Amino Acid Residue Critical for Plasma Membrane Localization of ATP-Binding Cassette Transporter G1--Brief Report.
- Author
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Gu HM, Wang F, Alabi A, Deng S, Qin S, and Zhang DW
- Subjects
- ATP Binding Cassette Transporter, Subfamily G, Member 1, ATP-Binding Cassette Transporters genetics, Amino Acid Substitution, Animals, Genotype, HEK293 Cells, Humans, Leucine, Lipoproteins genetics, Mice, Microscopy, Confocal, Mutation, Phenotype, Transfection, ATP-Binding Cassette Transporters metabolism, Cell Membrane metabolism, Cholesterol metabolism, Lipoproteins metabolism
- Abstract
Objective: ATP-binding cassette transporter G1 (ABCG1) mediates cholesterol efflux to lipidated lipoproteins. Conflicting data about cellular localization of ABCG1 and its effect on cholesterol efflux have been reported. Here, we investigated the underlying mechanisms for these different observations., Approach and Results: Confocal microscopy and biotinylation were used to assess cell surface localization of ABCG1. We found that mouse ABCG1 (mABCG1) used in one previous study has a substitution of Leu to Pro at position 550 (mG1-L550P). When the corresponding Leu at position 562 in human ABCG1 (hABCG1) was mutated to Pro (hG1-L562P), the mutant hABCG1, like mG1-L550P, mainly resided intracellularly, whereas wild-type mABCG1 and hABCG1 were localized on the plasma membrane. However, replacement of this Leu with Pro had no significant effect on mABCG1- and hABCG1-mediated cholesterol efflux., Conclusions: Leu at position 550/562 in mABCG1/hABCG1 is critical for their plasma membrane localization but not for ABCG1-mediated cholesterol efflux. Our findings indicate that the substitution of Leu to Pro at position 550 in mABCG1 may contribute to the non-cell surface localization of mABCG1 observed in the previous study., (© 2015 American Heart Association, Inc.)
- Published
- 2016
- Full Text
- View/download PDF
49. The assessment of immature microvascular density in brain gliomas with dynamic contrast-enhanced magnetic resonance imaging.
- Author
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Jia ZZ, Gu HM, Zhou XJ, Shi JL, Li MD, Zhou GF, and Wu XH
- Subjects
- Adolescent, Adult, Aged, Brain blood supply, Brain pathology, Brain Neoplasms pathology, Female, Glioma pathology, Humans, Male, Middle Aged, Reproducibility of Results, Statistics, Nonparametric, Young Adult, Brain Neoplasms blood supply, Contrast Media, Glioma blood supply, Image Enhancement, Magnetic Resonance Imaging methods, Microvessels
- Abstract
Purpose: This study was designed to quantitatively evaluate the immature microvascular density (MVD) of brain gliomas using the volume transfer constant (K(trans)) and volume of extravascular extracellular space per unit volume of tissue (Ve) from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) noninvasively., Materials and Methods: Fifty-seven patients (35 males, 22 females; age range, 14-70, mean age 46±12 years old) with brain glioma were included in this study. The maximal values of K(trans) and Ve of all patients with brain glioma (grade II 24, III 7 and IV 26) were obtained. The CD105-microvascular density (CD105-MVD) of each tumor was measured in surgical specimen. The differences of K(trans), Ve and CD105-MVD between the different grades of gliomas were analyzed using the Mann-Whitney U-test. The Pearman correlation coefficient was determined between K(trans), Ve and CD105-MVD. A P-value of less than 0.05 was considered statistically significant., Results: The differences in K(trans), Ve and CD105-MVD were statistically significant between low-grade glioma (LGG) and high-grade glioma (HGG) (P=0.001, P<0.001, P<0.001). The K(trans), Ve and CD105-MVD of grade II were significantly lower than those of grade III and IV. K(trans) and Ve were positively correlated with CD105-MVD in HGG (P<0.001, P<0.001)., Conclusions: Our results suggest DCE-MRI plays an important part in noninvasively evaluating the immature MVD of brain gliomas., (Copyright © 2015. Published by Elsevier Ireland Ltd.)
- Published
- 2015
- Full Text
- View/download PDF
50. Hypercholesterolemia, low density lipoprotein receptor and proprotein convertase subtilisin/kexin-type 9.
- Author
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Gu HM and Zhang DW
- Abstract
Atherosclerotic cardiovascular disease is the main cause of mortality and morbidity in the world. Plasma levels of low density lipoprotein cholesterol (LDL-C) are positively correlated with the risk of atherosclerosis. High plasma LDL concentrations in patients with hypercholesterolemia lead to build-up of LDL in the inner walls of the arteries, which becomes oxidized and promotes the formation of foam cells, consequently initiating atherosclerosis. Plasma LDL is mainly cleared through the LDL receptor (LDLR) pathway. Mutations in the LDLR cause familiar hypercholesterolemia and increase the risk of premature coronary heart disease. The expression of LDLR is regulated at the transcriptional level via the sterol regulatory element binding protein 2 (SREBP-2) and at the posttranslational levels mainly through proprotein convertase subtilisin/kexin-type 9 (PCSK9) and inducible degrader of the LDLR (IDOL). In this review, we summarize the latest advances in the studies of PCSK9.
- Published
- 2015
- Full Text
- View/download PDF
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