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Purpose: This study was undertaken to investigate the effects of gamma linolenic acid (GLA) on inflammation and extracellular matrix (ECM) synthesis in mesangial and tubular epithelial cells under diabetic conditions. Materials and Methods: Sprague-Dawley rats were intraperitoneally injected with either a diluent [n=16, control (C)] or streptozotocin [n=16, diabetes (DM)], and eight rats each from the control and diabetic groups were treated with evening primrose oil by gavage for three months. Rat mesangial cells and NRK-52E cells were exposed to medium containing 5.6 mM glucose and 30 mM glucose (HG), with or without GLA (10 or 100 µM). Intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1), and fibronectin (FN) mRNA and protein expression levels were evaluated. Results: Twenty-four-hour urinary albumin excretion was significantly increased in DM compared to C rats, and GLA treatment significantly reduced albuminuria in DM rats. ICAM-1, MCP-1, FN mRNA and protein expression levels were significantly higher in DM than in C kidneys, and these increases were significantly abrogated by GLA treatment. In vitro, GLA significantly inhibited increases in MCP-1 mRNA expression and protein levels under high glucose conditions in HG-stimulated mesangial and tubular epithelial cells (p<0.05, respectively). ICAM-1 and FN expression showed a similar pattern to the expression of MCP-1. Conclusion: GLA attenuates not only inflammation by inhibiting enhanced MCP-1 and ICAM-1 expression, but also ECM accumulation in diabetic nephropathy. [ABSTRACT FROM AUTHOR]

Background. Previous studies have demonstrated that AST-120 (Kremezin®), a well-known oral adsorbent, inhibits the progression of diabetic (DM) and non-DM chronic kidney disease along with a decrease in oxidative stress. This study was undertaken to investigate whether AST-120 could reduce oxidative stress and ameliorate the development of nephropathy in experimental DM rats with normal renal function. [ABSTRACT FROM PUBLISHER]

Previous studies have shown that mineralocorticoid receptor (MCR) blocker reduces proteinuria in diabetic nephropathy (DN), but the role of aldosterone in podocyte injury has never been explored in DN. This study was undertaken to elucidate whether a local aldosterone system existed in podocytes and to examine its role in podocyte apoptosis under diabetic conditions. In vitro, immortalized podocytes were exposed to 5.6 mM glucose (NG), NG + 24.4 mM mannitol, and 30 mM glucose (HG) with or without 10-7 M spironolactone (SPR). In vivo, 32 Sprague-Dawley rats were injected with diluent (C, n = 16) or streptozotocin intraperitoneally [diabetes mellitus (DM), n = 16], and 8 rats from each group were treated with SPR for 3 mo. Aldosterone synthase (CYP11B2) and MCR mRNA and protein expression were determined by real-time PCR and Western blot, respectively, and aldosterone levels by radioimmunoassay. Western blot for apoptosis-related molecules, Hoechst 33342 staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to determine apoptosis. CYP11B2 and MCR expression were significantly higher in HG-stimulated podocytes and DM glomeruli compared with NC cells and C glomeruli, respectively, along with increased aldosterone levels. Western blot analysis revealed that cleaved caspase-3 and Bax expression was significantly increased, whereas Bcl-2 expression was significantly decreased in HG-stimulated podocytes and in DM glomeruli. Apoptosis determined by Hoechst 33342 staining and TUNEL assay were also significantly increased in podocytes under diabetic conditions. These changes in the expression of apoptosis-related proteins and the increase in apoptotic cells were inhibited by SPR treatment. These findings suggest that a local aldosterone system is activated and is involved in podocyte apoptosis under diabetic conditions. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated that an inflammatory mechanism contributes to the pathogenesis of diabetic nephropathy (DN). It is also known that colchicine (Col) can prevent various renal injuries via its anti-inflammatory action. However, the effect of colchicine on DN has never been explored. This study was undertaken to elucidate the effect of colchicine on inflammation and extracellular matrix accumulation in DN. In vivo, 64 rats were injected with diluent (C; n = 32) or streptozotocin intraperitoneally (DM, n = 32). Sixteen rats from each group were treated with Col. In vitro, rat mesangial cells and NRK-52E cells were cultured in media with 5.6 mM glucose (NG) or 30 mM glucose (HG) with or without 10-8 M Col. Monocyte chemotactic protein-1 (MCP-1) mRNA expression was determined by real-time PCR (RT-PCR), and the levels of MCP-1 in renal tissue and culture media were measured by ELISA. RT-PCR and Western blotting were also performed for intercellular adhesion molecule-1 (ICAM-1) and fibronectin (FN) mRNA and protein expression, respectively, and immunohistochemical staining (IHC) for ICAM-1, FN, and ED-1 with renal tissue. Twenty-four-hour urinary albumin excretion at 6 wk and 3 mo were significantly higher in DM compared with C rats (P < 0.05), and colchicine treatment significantly reduced albuminuria in DM rats (P < 0.05). Col significantly inhibited the increase in MCP-1 mRNA expression and protein levels under diabetic conditions both in vivo and in vitro. ICAM-1 and FN expression showed a similar pattern to the expression of MCP-1. IHC revealed that the number of ED-1(+) cells were significantly higher in DM compared with C kidney (P < 0.005), and this increase was significantly attenuated by Col treatment (P < 0.01). In conclusion, Col prevents not only inflammatory cell infiltration via inhibition of enhanced MCP-1 and ICAM-1 expression but also ECM accumulation in DN. These findings provide a new perspective on the renoprotective effects of Col in DN. [ABSTRACT FROM AUTHOR]

Monocyte chemoattractant protein-1 (MCP-l) is a potent chemokine that plays an important role in the recruitment of macrophages. Although previous studies have demonstrated the importance of MCP-1 in the pathogen- esis of diabetic nephropathy (DN) in terms of inflammation, the role of MCP-1 and its receptor (C-C chemokine receptor 2; CCR2) in extracellular matrix (ECM) accumulation under diabetic conditions has been largely unexplored. This study was undertaken to investigate the functional role of the MCP-1/CCR2 system in high glucose-induced ECM (fibronectin and type IV collagen) protein expression in cultured mesangial cells (MCs). Mouse MCs were exposed to medium containing 5.6 mM glucose (NG), NG+24.4 mM mannitol (NG+M), or 30 mM glucose (HG) with or without mutant MCP-1 (mMCP-1), CCR2 small interfering (si)RNA, or CCR2 inhibitor (RS102895). To examine the relationship between MCP-1 and transforming growth factor (TGF)-β1, MCs were also treated with TGF-β1 (2 ng/ml) with or without mMCP-l or CCR2 siRNA. Transient transfection was performed with Lipofectamine 2000 for 24 h. Cell viability was determined by an MTT assay, mouse and human MCP-1 and TGF-β1 levels by ELISA, and CCR2 and ECM protein expression by Western blotting. Transfections of mMCP-1 and CCR2 siRNA increased human MCP-1 levels and inhibited CCR2 expression, respectively. HG-induced ECM protein expression and TGF-β1 levels were significantly attenuated by mMCP-1, CCR2 siRNA, and RS 102895 (P < 0.05). MCP-1 directly increased ECM protein expression, and this increase was inhibited by an anti-TGF-β1 antibody. In addition, TGF-β1-induced ECM protein expression was significantly abrogated by the inhibition of the MCP-1/CCR2 system (P < 0.05). These results suggest that an interaction between the MCP-1/CCR2 system and TGF-β1 may contribute to ECM accumulation in DN. [ABSTRACT FROM AUTHOR]

Previous in vitro studies suggest that the p38 MAPK pathway may be involved in the pathogenesis of diabetic nephropathy, but the consequences of the inhibition of the p38 MAPK pathway have not been well elucidated in diabetic (DM) glomeruli. This study was undertaken to investigate the effect of p38 MAPK inhibitor, FR167653, on fibronectin expression and apoptosis in DM glomeruli and in high-glucose-stimulated mes- angial cells (MC). In vivo, 32 Sprague-Dawley rats were injected with diluent (control, N = 16) or streptozotocin intraperitoneally (DM, N = 16). Eight rats from each group were treated with FR167653 for 3 mo. In vitro, rat MC were exposed to medium containing 5.6 mM glucose or 30 mM glucose [high glucose (HG)I with or without 10-6 M FR 167653 for 24 h. Fibronectin mRNA and protein expression were determined by real-time PCR and Western blot, respectively. Western blot for apoptosis-related molecules, terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling assay, and Hoechst 33342 staining were performed to determine apoptosis. FR167653 ameliorated the increases in fibronectin-to-GAPDH mRNA ratio and protein expression in DM glomeruli by 89 and 79% and in HG-stimulated MC by 70 and 91%, respectively (P < 0.05). Under diabetic conditions, Bcl-2 protein expression was decreased, whereas cleaved caspase-3 protein expression was increased (P < 0.05), and these changes were inhibited by FR167653 treatment. Apoptotic cells were also significantly increased in DM glomeruli and in HG-stimulated MC (P < 0.05), and FR167653 ameliorated these increases in apoptotic cells, both in vivo and in vitro. In conclusion, these findings suggest that the inhibition of the p38 MAPK pathway has a beneficial effect on the development of diabetic nephropathy by inhibiting the increase in fibronectin expression and apoptosis. [ABSTRACT FROM AUTHOR]

Genes of the major histocompatibility complex (MHC) influence the urinary odors of mice. Behavioral studies have shown (1) that mice differing only at MHC have distinct urinary odors, suggesting an MHC odor phenotype or odortype; (2) that the MHC odortype can be recognized across different background strains; and (3) that the MHC odortype is not an additive trait. Very little is known about the odorants underlying this behavioral phenotype. We compared urinary volatile profiles of two MHC haplotypes (H2b and H2k) and their heterozygous cross (H2b×H2k) for two different background strains ( C57BL/6J and BALB/c) using solid phase micro-extraction (SPME) headspace analysis and gas chromatography/mass spectrometry (GC/MS). Both MHC and background genes substantially influence the volatile profile. Of 148 compounds screened, 108 of them significantly differ between the six genotypes. Surprisingly, for numerous compounds, their MHC associations are moderated by background genes (i.e., there is a significant MHC × background interaction effect in the statistical model relating genotype to relative compound concentration). These interactions account for nearly 30% of the total genetic effect on the volatile profile. MHC heterozygosity further extends the odortype diversity. For many compounds, the volatile expression for the heterozygote is more extreme than the expression for either homozygote, suggesting a heterozygous-specific odortype. The remarkable breadth of effects of MHC variation on concentrations of metabolites and the interaction between MHC and other genetic variation implies the existence of as yet unknown processes by which variation in MHC genes gives rise to variation in volatile molecules in body fluids. [ABSTRACT FROM AUTHOR]

Background. Peritoneal fibrosis (PF), a serious problem in long-term continuous ambulatory peritoneal dialysis (CAPD) patients, is characterized by extracellular matrix (ECM) accumulation which results from an imbalance between the synthesis and the degradation of ECM components. Previous studies have demonstrated that ECM synthesis is increased in human peritoneal mesothelial cells (HPMCs) under high glucose conditions, but the effects of high glucose on degradative pathways have not been fully explored. This study was undertaken to elucidate the effects of high glucose on these proteolytic processes in cultured HMPCs. Methods. HPMCs were isolated from human omentum and were exposed to 5.6 mM glucose (NG), 5.6 mM glucose +34.4 mM mannitol (NG + M), or 40 mM glucose (HG) with or without PKC inhibitor (PKCi). Real-time PCR and western blot were performed to determine collagenases (MMP-1, -8 and -13) and TIMPs (TIMP-1 and -2) mRNA and protein expression, respectively. The individual activities of collagenases in culture media were determined by ELISA. Results. Types I and III collagen protein expression were significantly increased in HG-conditioned media compared to NG media (P vs NG-conditioned media. The activities of collagenases in HG-conditioned media were also significantly lower than those in NG media (P Conclusion. In conclusion, impaired matrix degradation may contribute to ECM accumulation in PF. [ABSTRACT FROM AUTHOR]

Background. Compared to children, adult patients with minimal change disease (MCD) tend to have a slower response to steroids, but little is known about the factors influencing the steroid responsiveness in these patients. In this study, we investigated the difference in the expression of the glomerular glucocorticoid receptor (GCR) according to steroid responsiveness in 28 adult-onset MCD patients. Methods. Based on the response to steroid treatment, the patients were divided into early responders (ER, n = 20) and late responders (LR, n = 8) according to the response to steroids on the basis of 4 weeks of treatment. The clinical and laboratory findings, and the glomerular mRNA and protein expression of GCR and nephrin, assessed by real-time polymerase chain reaction and immunohistochemistry, respectively, were compared between the ER and LR groups. Ten microscopic haematuric patients in whom renal biopsy was performed and revealed no histological abnormalities were included for control (C). Results. The mRNA expression of GCR was significantly lower in the LR than that in the ER group (P r = −0.49, P Conclusion. In conclusion, the levels of glomerular GCR expression may be a useful predictor of steroid responsiveness in adult-onset MCD patients. [ABSTRACT FROM AUTHOR]

Since the 1990s, efforts have been made to reduce the damage caused by natural disasters, among which the Disaster Impact Assessment (DIA) System implemented in 1995 is noteworthy for its proactive response. The DIA System has undergone various institutional and technological changes to retain its original purpose. However, its operation has become inadequate because of the diversification of business types. This paper presents the improvements required in the DIA System based on an analysis of the problems that have emerged during its institutional development and over 9000 pieces of data collected from 2015 to 2017. The results show that, first, the DIA’s Practical Guidelines should be subdivided, considering the diversity of projects. Second, the system should be strengthened to ensure it is not mistaken for a mere bureaucratic box-ticking exercise. Third, non-structural measures should be expanded to reduce the number of casualties after development. Incorporating the improvements proposed in this study will improve the effectiveness of the DIA. Additionally, the DIA System could be established as an important model for Korea’s disaster risk reduction activities.

Hispidulin is abundant in Arrabidaea chica, Crossostephium chinense, and Grindelia argentina, among others. p-Synephrine is the main phytochemical constituent of Citrus aurantium. It has been used in combination with various other phytochemicals to determine synergistic effects in studies involving human participants. However, there have been no reports comparing the anti-adipogenic effects of the combination of hispidulin and p-synephrine. The current study explores the anti-adipogenic effects of hispidulin alone and in combination with p-synephrine in a murine preadipocyte cell line, 3T3-L1. Co-treatment resulted in a greater inhibition of the formation of red-labeled lipid droplets than the hispidulin or p-synephrine-alone treatments. Co-treatment with hispidulin and p-synephrine also significantly inhibited adipogenic marker proteins, including Akt, mitogen-activated protein kinases, peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein alpha, glucocorticoid receptor, and CCAAT/enhancer-binding protein β. Although further studies are required to assess the effects of each drug on pharmacokinetic parameters, a combination treatment with hispidulin and p-synephrine may be a potential alternative strategy for developing novel anti-obesity drugs.

Avocado oil is beneficial to human health and has been reported to have beneficial effects on sensorineural hearing loss (SNHL). However, the compounds in avocado oil that affect SNHL have not been identified. In this study, we identified 20 compounds from avocado oil, including two new and 18 known fatty acid derivatives, using extensive spectroscopic analysis. The efficacy of the isolated compounds for improving SNHL was investigated in an ototoxic zebrafish model. The two new compounds, namely (2R,4R,6Z)-1,2,4-trihydroxynonadec-6-ene and (2R,4R)-1,2,4-trihydroxyheptadecadi-14,16-ene (compounds 1 and 2), as well as compounds 7, 9, 14, 17 and 19 showed significant improvement in damaged hair cells in toxic zebrafish. These results led to the conclusion that compounds from avocado oil as well as oil itself have a regenerative effect on damaged otic hair cells in ototoxic zebrafish.

Heme oxygenase-1 (HO-1) is an anti-oxidant enzyme normally upregulated in response to oxidant injury. Here we determined the role of HO-1 in podocyte apoptosis in glomeruli of streptozotocin-treated rats and in immortalized mouse podocytes cultured in media containing normal or high glucose. HO-1 expression, its activity, the ratio of Bax/Bcl-2 protein, and active caspase-3 fragments were all significantly higher in isolated glomeruli of diabetic rats and in high glucose–treated podocytes. These increases were inhibited by zinc protoporphyrin treatment of the rats or by HO-1 siRNA treatment of the podocytes in culture. The number of apoptotic cells was also significantly increased in the glomeruli of diabetic rats and in high glucose–treated podocytes. Inhibition of HO-1 accentuated the increase in apoptotic cells both in vivo and in vitro. Our findings suggest that HO-1 expression protects against podocyte apoptosis under diabetic conditions. [ABSTRACT FROM AUTHOR]