BACKGROUND Mizagliflozin(MIZ)is a specific inhibitor of sodium-glucose cotransport protein 1(SGLT1)originally developed as a medication for diabetes.AIM To explore the impact of MIZ on diabetic nephropathy(DN).METHODS...BACKGROUND Mizagliflozin(MIZ)is a specific inhibitor of sodium-glucose cotransport protein 1(SGLT1)originally developed as a medication for diabetes.AIM To explore the impact of MIZ on diabetic nephropathy(DN).METHODS Diabetic mice were created using db/db mice.They were administered either a low dose(0.5 mg/kg)or a high dose(1.0 mg/kg)of the SGLT1 inhibitor MIZ via stomach gavage for 8 weeks.Subsequently,mesangial cells(MCs)were isolated and subjected to high glucose conditions in culture to assess the effects of MIZ on DN.RESULTS The results showed that low doses of MIZ significantly reduced albuminuria to a level comparable to that achieved with high doses in db/db mice.High doses of MIZ led to a substantial increase in body weight in mice,along with decreased blood glucose levels and food intake.Moreover,the intervention with high-dose MIZ notably decreased the expression of extracellular matrix genes,such as collagen type 1 alpha 1 mRNA levels.While the expression of SGLT1 increased after exposure to high glucose,it decreased following treatment with MIZ.Furthermore,MIZ intervention was more effective in improving lactate dehydrogenase levels in MCs induced by high glucose compared to canagliflozin.MIZ also significantly elevated levels of antioxidant enzymes superoxide dismutase,catalase,and glutathione,while reducing malondialdehyde levels.CONCLUSION These findings indicate that MIZ can ameliorate DN by inhibiting SGLT1,inflammation,and oxidative stress.展开更多
Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose ...Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose (30, 50, 80 mmol/L). The cell growth was observed by using MTT method and apoptosis by using an aunexin-V-Fluos. Immunohistochemical studies for Laminin (LN), Fibronectin (FN) and type Ⅳ Collagens (Col Ⅳ) were measured. Results: Shikonin inhibited their growth (P<0.05) and apoptosis in the glycated cultured cells. Shikonin 0.05 mmol/L significantly reduced the secretion of LN, FN and Col Ⅳ from MC (P<0.05) cultured in 30, 50 and 80 mmol/L glucose. Conclusion: Shikonin could prevent or treat diabetic nephropathy (DN) and glomerulosclerosis (GS).展开更多
Objective:To examine whether lipoxin A 4(LXA 4) has an inhibitory effect on tumor necrosis factor-α(TNF-α)-induced proliferation of glomerular mesangial cells of rat, and explore the molecular mechanisms of signal...Objective:To examine whether lipoxin A 4(LXA 4) has an inhibitory effect on tumor necrosis factor-α(TNF-α)-induced proliferation of glomerular mesangial cells of rat, and explore the molecular mechanisms of signal pathway in LXA 4 actions. Methods: Glomerular mesangial cells of rat were cultured and treated with TNF-α(10 ng/ml), with or without preincubation with LXA 4 at different concentrations. Cell proliferation was evaluated by monotetrazolium (MTT) colorimetric assay. The expression of cyclin E mRNA was measured by RT-PCR. Phosphorylated Akt1(Thr308) and p27 kip1 were analyzed by Western blotting. Results: TNF-α-stimulated proliferation of mesangial cells was inhibited by LXA 4 in a dose-dependent manner. The marked increments in cyclin E mRNA expression induced by TNF-α during proliferation of mesangial cells were down-regulated by LXA 4. Threonine phosphorylated Akt1 proteins at 308 site stimulated by TNF-α was reduced by LXA 4. TNF-α-induced decrements in expression of p27 kip1 proteins was ameliorated by LXA 4 in a dose-dependent manner. Conclusion: TNF-α-induced proliferation of rat mesangial cells can be inhibited by TXA 4 through the mechanism of Akt 1/p27 kip1 pathway-dependent signal transduction.展开更多
Objective: To explore the effect of L158, 809 (angiatensin Ⅱ receptorMockers, ARBs) and Cilazapril (Angiotensin converting enzyme inhibitor, ACEI) on the expression oftransforming growth factor-β_1 (TGF-β_1) and se...Objective: To explore the effect of L158, 809 (angiatensin Ⅱ receptorMockers, ARBs) and Cilazapril (Angiotensin converting enzyme inhibitor, ACEI) on the expression oftransforming growth factor-β_1 (TGF-β_1) and secretion of fibronectin, laminin and type Ⅳcollagen from the cultured human mesangial cells . Methods: Human mesangial cells were cultured indifferent glucose (5.6 mmol/L and 30 mmol/L) and agents (1, 10, 100 and 500 μmol/L) concentrations. The proliferation of mesangial cells were detected at 24, 48 and 72 h . Then the mesangial cellsare divided into four groups, low glucose (5.6 mmol/L) control group, high glucose (30 mmol/L)control group , L158, 809 (10 μmol/L) group and cilazapril (10 μmol/L) group. Forty- eight hourslater, the expression of TGF-β_1 were detected by RT-PCR. Concentrations of TGF-β_1 ,fibronection, laminin and type Ⅳ collagen in the su-pematants of the, mesangial cells weredetermined by EUSA and radioimmunoassay methods. Results: Compared with low glucose control group,the mesangial cells under high glucose medium show excessive proliferation and more TGF-β_1,fibronectin, laminin and type Ⅳ collagen in the supernatant. The expression of TGF-β_1 mRNA wasalso significantly increased under high glucose. The levels of TGF-β_1 and ECM (extracellularmatrix) proteins in the L158, 809 group and cilazapril group are obviously lower than that of thehigh glucose control group. The expression of TGF-β_1 mRNA was markedly decreased in the L158, 809group and cilazapril group compared with that of high glucose control group . Conclusion: Highglucose stimulated the cultured human mesangial cells to excessively proliferate, express TGF-β_1and secrete ECM proteins, and the high glucose-indeced changes were suppressed by either L158, 809and cilazapril.展开更多
The X gene of HBV encodes a 17-kD protein, termed HBx, which has been shown to function as a transcriptional trans-activator of a variety of viral and cellular promoter/enhancer elements. The aim of this study was to ...The X gene of HBV encodes a 17-kD protein, termed HBx, which has been shown to function as a transcriptional trans-activator of a variety of viral and cellular promoter/enhancer elements. The aim of this study was to investigate the effect of HBx on gene expression of interleukin （IL）-1β and IL-6, and proliferation of rat mesangial cells in vitro. The X gene of HBV was amplified by PCR assay, and inserted into the eukaryotic expression vector pCI-neo. The structure of recombinant pCI-neo-X plasmid was proved by restrict endonuclease digestion and sequencing analysis. pCI-neo-X was transfected into cultured rat mesangial cell line in vitro via liposome. HBx expression in transfected mesangial cells was detected by Western blot. The IL-1β and IL-6 mRNA expression in those cells was assayed by semiquantitative RT-PCR. Mesangial cell proliferation was tested by MTT. The results showed that HBx was obviously expressed in cultured mesangial cell line at 36th and 48th h after transfection. The expression of IL-1β and IL-6 mRNA was simultaneously increased. The cell proliferation was also obvious at the same time. It was concluded that HBx gene transfection could induce IL-1β and IL-6 gene expression and mesangial cell proliferation. HBx may play a critical role in mesangial cell proliferation through upregulation of the IL-1β and IL-6 gene expression.展开更多
OBJECTIVE:To investigate the effect of mitofusin 2 (Mfn2) and its downstream signaling pathway on glomerular mesangial cells (GMCs) proliferation in IgA nephropathy (IgAN),as well as the mechanism of action of Jixueca...OBJECTIVE:To investigate the effect of mitofusin 2 (Mfn2) and its downstream signaling pathway on glomerular mesangial cells (GMCs) proliferation in IgA nephropathy (IgAN),as well as the mechanism of action of Jixuecao (Herba Centellae Asiaticae,HCA) in the treatment of IgAN.METHODS:Adenovirus-mediated Mfn2 gene transfection and Mfn2 expression were analyzed by real-time polymerase chain reaction (PCR) and Western blotting.IgA1 induced the proliferation of GMCs,which were then treated with HCA.Cell proliferation was detected with cell counting kit-8 (CCK-8),and Mfn2 expression was analyzed by real-time PCR and western blotting.An IgAN animal model was also established and treated with HCA.GMCs proliferation was detected by hematoxylin-eosin staining,mitochondrial structure was analyzed by electron microscopy,mitochondrial function was determined by the Clark oxygen electrode method,and the expression of Mfn2,Phospho-extracellular regulated protein kinases1/2 (P-ERK1/2),Cyclin-dependent kinase 2 (CDK2),Phospho-p27 (p-p27),and cyclin A was analyzed by Western blotting.RESULTS:In vitro,HCA inhibited GMCs in a concentration-dependent manner in association with the upregulation of Mfn2 expression.The overexpression of Mfn2 inhibited IgA1-induced GMCs proliferation and elevated the effect of HCA.In vivo,treatment with HCA could alleviate albuminuria and creatinine and GMCs proliferation.These effects were related to the upregulation of Mfn2,p-p27 and inhibition of p-ERK1/2,CDK2,and cyclinA.Mitochondrial swelling,vacuolar degeneration,and reduction of respiratory control rate were identified in IgAN,but HCA could improve the mitochondrial structure and function.CONCLUSION:HCA inhibited GMCs proliferation via the upregulation Mfn2 and the inhibition of Ras-Raf-ERK/MAPK.We revealed that changes of mitochondrial structure and function are associated with IgAN,but that HCA can improve these mitochondrial features.展开更多
Diabetic kidney disease (DKD)is a microvascular complication of type 2 diabetes.The study of DKD mechanisms is the most important target for the prevention of DKD.Renal senescence is one of the important pathogeneses ...Diabetic kidney disease (DKD)is a microvascular complication of type 2 diabetes.The study of DKD mechanisms is the most important target for the prevention of DKD.Renal senescence is one of the important pathogeneses for DKD,but the mechanism of renal and cellular senescence is unclear.Decreased expression of circulating miR-126 is associated with the development of DKD and may be a promising blood-based biomarker for DKD.This study is to probe the effect and mechanism of miR-126 on the aging of human glomerular mesangial cells (HGMCs)induced by high glucose.HGMCs were cultured with Roswell Park Memorial Institute (RPMI-1640)in vitro.The effect of high glucose on morphology of HGMCs was observed 72h after intervention.The cell cycle was examined by flow cytometry.The telomere length was measured by Southern blotting.The expression levels of p53,p21 and Rb proteins in p53-p21-Rb signaling pathway and p-statl,p-stat3 in JAK/STAT signaling pathway were detected by Western blotting respectively.The expression of miR-126 was examined by qRT-PCR.MiR-126 mimics was transfected into HGMCs.The effects of miR-126 mimics transfection on cell morphology,cell cycle,telomere length,p53,p21,Rb,p-stat1 and p-stat3 were observed. The results showed that high glucose not only arrested the cell cycle in G1phase but also shortened the telomere length.High glucose led to high expression of p53,p21,Rb,p-statl and p-stat3 and premature senescence of HGMCs by activating the telomere-p53-p21-Rb and JAK/STAT signaling pathways.Moreover,the miR-126 was decreased in HGMCs induced by high glucose.It was suggested that the transfection of miR-126 mimics could inhibit the telomere-p53-p21-Rb and JAK/STAT signaling pathway activity in vitro and delay the senescence of HGMCs.The results may serve as a new strategy for the treatment of DKD.展开更多
Objective To study the expressions of MMP-2 and TIMP-2 mRNA on cultured rat mesangial cells (MsC) and in human diseased glomeruli, and to explore their significance in the development of glomerulosclerosis. Methods Th...Objective To study the expressions of MMP-2 and TIMP-2 mRNA on cultured rat mesangial cells (MsC) and in human diseased glomeruli, and to explore their significance in the development of glomerulosclerosis. Methods The expressions of MMP-2, TIMP-2, and Col ⅣmRNA on cultured rat MsC stimulated by IL-1 or/and TGF-β1were investigated through Northern blot analysis. The levels of MMP-2 and TIMP-2 mRNA expressions and immunoreacti-vity of PCNA and Col Ⅳin human diseased glomeruli from renal biopsies of lupus nephritis (LN) patients were examined by insituhybridization and immunohistochemistry, respectively. Results The levels of MMP-2, TIMP-2, and Col ⅣmRNA expressions were markedly increased on cultured rat MsC stimulated by IL-1 or/and TGF-β1. Meanwhile, upregulation of MMP-2 and TIMP-2 mRNA expressions was confirmed in diseased glomeruli from patients with various subtypes of LN, and was closely related to the positive cell number of PCNA presentation and deposition of Col Ⅳin glomeruli. Conclusion The results suggest that the over-expressions of MMP-2 and TIMP-2 mRNA on glomerular cells might play a critical role in the development of glomerulosclerosis.展开更多
OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by ...OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by our laboratory was used to detect the localization of AM protein in rat kidney tissue by avidin-biotin complex immunohistochemistry. The expressions of AM and its receptor CRLR mRNA on cultured glomerular epithelial cells (GEC) and MsC were investigated by Northern blot assay, and the possible effect of AM secreted by GEC on MsC proliferation was observed using [3H]thymidine incorporation as an index. RESULTS: A specific monoclonal antibody against AM was succesfully developed. AM was immunohistochemically localized mainly in glomeruli (GEC and endothelial cells), some cortical proximal tubules, medullary collecting duct cells, interstitial cells, vascular smooth muscle cells and endothelial cells. Northern blot assay showed that AM mRNA was expressed only on cultured GEC, but not on MsC, however, AM receptor CRLR mRNA was only expressed on MsC. GEC conditioned medium containing AM can inhibit MsC growth and AM receptor blocker CGRP8-37 may partially decreased this inhibitory effect. CONCLUSION: AM produced by GEC inhibits the proliferation of MsC, which suggests that AM as an important regulator is involved in glomerular normal physiological functions and pathologic processes.展开更多
AIM： To delineate the mechanisms of renal vasoconstriction in hepatorenal syndrome （HRS）, we investigated the expression of type I inositol 1, 4, 5-triphosphate receptors （IP3R I） of kidney in mice with fulminant...AIM： To delineate the mechanisms of renal vasoconstriction in hepatorenal syndrome （HRS）, we investigated the expression of type I inositol 1, 4, 5-triphosphate receptors （IP3R I） of kidney in mice with fulminant hepatic failure （FHF）. METHODS： FHF was induced by lipopolysaccharide （LPS） in D-galactosamine （GAIN） sensitized BALB/c mice. There were 20 mice in normal saline （NS）-treated group, 20 mice in LPS-treated group, 20 mice in GaIN- treated group, and 60 mice in GalN/LPS-treated group （FHF group）. Liver and kidney tissues were obtained at 2, 6, and 9 h after administration. The liver and kidney specimens were stained with hematoxylin-eosin for studying morphological changes under light microscope. The expression of IP3R I in kidney tissue was tested by immunohistochemistry, Western blot and reverse transcription （RT）-PCR. RESULTS： Kidney tissues were morphologically normal at all time points in all groups. IP3R I proteins were found localized in the plasma region of glomerular mesangial cells （GMC） and vascular smooth muscle cells （VSMC） in kidney by immunohistochemical staining. In kidney of mice with FHF at 6 h and 9 h IP3R I staining was upregulated. Results from Western blot demonstrated consistent and significant increment of IP3R I expression in mice with FHF at 6 h and 9 h （t = 3.16, P 〈 0.05; t = 5.43, P 〈 0.01）. Furthermore, we evaluated IP3R I mRNA expression by RT-PCR and observed marked upregulation of IP3R I mRNA in FHF samples at 2 h, 6 h and 9 h compared to controls （t = 2.97, P 〈 0.05; t = 4.42, P 〈 0.01; t = 3.81, P 〈 0.01）. CONCLUSION： The expression of IP3R I protein increased in GMC and renal VSMC of mice with FHF, possibly caused by up-regulation of IP3R I mRNA.展开更多
The crude polysaccharide was obtained by means of the decolorization of porphyrized Cordyceps minlitaris stroma with organic solvent, extraction with hot water, precipitation in 80% ethanol, and protein removal with t...The crude polysaccharide was obtained by means of the decolorization of porphyrized Cordyceps minlitaris stroma with organic solvent, extraction with hot water, precipitation in 80% ethanol, and protein removal with the Sevag method. After purification with Sephadex G-75, two of its components, CMP-1 and CMP-2, were obtained. Through the assay of gel chromatography and polarimetry, CMP-1 was identified as pure polysaccharide. The results demonstrated that CMP-1 had favorable oxidation resistance activity, which could scavenge not only oxygen-free radicals in the self-oxidation system of pyrogallic acid, but also the hydroxide-free radicals in the Fenton system. The study focused on the effects of low, medium, and high dosages of CMP-1 in rat blood serum on the proliferation of glomerular mesangial cells in vitro. Through MTT Colorimetric analysis, the activities were compared among the blank control group and the Niaoduqing positive control group CMP-1 and CMP-2. The results shows that CMP-1 was able to inhibit the proliferation of rat glomerular mesangial cells effectively. Therefore, CMP-1, one component of polysaccharides of Cordyceps minlitaris, was certainly a potential remedy for hyperplastic glomerular nephritis, whose antioxidant activity could slow down the process of chronic renal failure（CRF） to some extent.展开更多
OBJECTIVE: To investigate the effect of the clinical effective prescription of Qingre Lishi Yishen decoction(QRLS) on the activation of mesangial cells in immunoglobulin A nephropathy(IgAN) rats.METHODS: IgAN rat’s m...OBJECTIVE: To investigate the effect of the clinical effective prescription of Qingre Lishi Yishen decoction(QRLS) on the activation of mesangial cells in immunoglobulin A nephropathy(IgAN) rats.METHODS: IgAN rat’s model was established by combine with intragastric administration of bovine serum albumin(BSA) + intravenous injection of lipopolysaccharide(LPS) by + subcutaneous injection of carbon tetrachloride(CCL4). Then the animals were randomly divided into four groups: control group, IgAN model group, IgAN model with Valsartan(Val) treatment group and IgAN model with QRLS treatment group. To observe the indexes of 24-h urine protein, renal function, deposition of immune complexes, expression of activation factor, fibrosis marker and inflammatory cytokines in four different groups.RESULTS: The Val or QRLS treatment group:(a) it reduced the immune complexes deposition of IgA in glomerular mesangial and inhibited mesangial cell proliferation;(b) it decreased the expression of smooth muscle actin(α-SMA), fibronectin(FN) and tumor necrosis factor alpha(TNF-α).CONCLUSION: The study suggested that QRLS ameliorate renal structure and function in IgAN rat’s model. Furthermore, we also observed that QRLS alleviated mesangial cells activation and matrix accumulation partly by decreasing the α-SMA,then to downregulated the expression of FN and TNF-α.展开更多
Objective：To investigate the effects of emodin（EMD） on cell proliferation and correlative cytokines secretion of glomerular mesangial in rats. Methods：The effects of EMD on cell proliferation and IL-6, TGF-β1 sec...Objective：To investigate the effects of emodin（EMD） on cell proliferation and correlative cytokines secretion of glomerular mesangial in rats. Methods：The effects of EMD on cell proliferation and IL-6, TGF-β1 secretion of glomerular mesangial in rats were observed. Cell proliferation was measured by MTT method. IL-6 and TGF-β1 secretion was detected with ELISA. Results：EMD was able to inhibit the cell proliferation and down-regulate the IL-6 and TGF-β 1 secretion of glomerular mesangial, as compared to the model group in rats （P 〈 0.05）. Conclusion：EMD could significantly inhibit the cell proliferation, and reduce the creation of extracellular matrix（ECM）, this indicated that it could play an important role in alleviation and prevention of glomerular sclerosis. The mechanism may be that EMD can reduce the IL-6 and TGF-β1 secretion ofglomerular mesangial cell in rats.展开更多
Interleukin-10(IL-10), a cytokine with anti-inflammatory and immunomodulatory functions, regulates the biology of B and T cells. The present review describes the role of IL-10 in normal renal physiology, during acute ...Interleukin-10(IL-10), a cytokine with anti-inflammatory and immunomodulatory functions, regulates the biology of B and T cells. The present review describes the role of IL-10 in normal renal physiology, during acute kidney injury and in the development of chronic renal failure. We further discuss IL-10-induced cellular and molecular pathways and their link to the progression of kidney injury.展开更多
The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By usin...The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 （SD） could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP （FP） under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 （KN） could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.展开更多
Summary： To study the efficacy and the mechanism of Colquhoumia root （ Tripterygium hypoglaucure （Le,vL） Hutch） in the treatment of mesangial proliferation glomerulonephritis （MsPGN）, SD rats were injected with...Summary： To study the efficacy and the mechanism of Colquhoumia root （ Tripterygium hypoglaucure （Le,vL） Hutch） in the treatment of mesangial proliferation glomerulonephritis （MsPGN）, SD rats were injected with anti-thymoeyte serum （ATS） to make MsPGN model （anti-Thyl model）. The rats were then divided into 3 groups： normal control group, anti-Thyl model group and treatment group. Histopathologieal （HE, PAS）, immunohistoehemieal, RT-PCR technique and computer imaging analysis system were used to evaluate mesangial matrix production, the expression of TGF-β protein and mRNA in the tissues of kidney. Our result showed that proteinuria and the ratio of extraeellular matrix/glomerular capillaries area （ECM/CA） were increased significantly in model group. The expression of both TGF-β protein and mRNA in glomeruli was much higher in model group than in control group （P〈0.01）. After the treatment with Colquhoumia root, proteinuria, ECM/CA and the expression of both TGF-β1 protein and mRNA in glomeruli were significantly decreased in treatment group as compared with those in model group. It is concluded that Colquhoumia root is effective in reducing proteinuria and mesangial matrix proliferation in MsPGN and it may achieve these effects by inhibiting the expressions of TGF-β1 protein and mRNA of mesangial cells.展开更多
Objective: To examine whether lipoxin A 4 (LXA 4) has an antagonistic effect on IL-1β-induced synthesis of IL-6 in glomerular mesangial cells, and to explore the molecular mechanisms of signal pathway in LXA 4 ...Objective: To examine whether lipoxin A 4 (LXA 4) has an antagonistic effect on IL-1β-induced synthesis of IL-6 in glomerular mesangial cells, and to explore the molecular mechanisms of signal pathway in LXA 4 actions. Methods: The glomerular mesangial cells of rat were cultured and treated with IL-1β, with or without preincubation with LXA 4 at different concentrations. The amount of IL-6 in the supernatant of cells was analyzed by enzyme-linked immunosorbent assay(ELISA). The expressions of mRNA of IL-6 were determined by RT-PCR. The expressions of Src homology 2(SH 2) containing protein-tyrosine phosphatase 2(Shp-2) were assessed by immunoprecipitation and immunoblotting. Activities of DNA-binding of nuclear factor-kappa B(NF-κB) were measured by electrophoretic mobility shift assay(EMSA). Results: IL-1β-stimulated secretion of protein and expression of mRNA of IL-6 in mesangial cells were inhibited by LXA 4 in a dose-dependent manner. LXA 4 antagonizes the phosphorylation of Shp-2 and activities of NF-κB induced by IL-1β. Conclusion: LXA 4 antagonists IL-1β-induced synthesis of IL-6 in glomerular mesangial cells through the mechanism of Shp-2/NF-κB pathway-dependent signal transduction.展开更多
Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process.Its precise mechanism is not fully known. In recent years it has been recognized that synthesis of various extracelluar ...Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process.Its precise mechanism is not fully known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase, and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro. The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture medium were 0, 25, 50,100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium. They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed a 0. 61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when compared to cells grown without heparin. In Western blot analysis,MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high glucose medium. Incubation of heparin further increased expression of MMP1, MMP2, MMP3 and MMP9. Conclusions This study suggests that glucose can accelerate mesangial cell proliferation while heparin can reduce proliferation, being more obvious at high glucose concentrations. Higher glucose concentrations led to increased MMP expression, which may take part in the regulation of mesangial matrix synthesis and degradation. Addition of heparin resulted in a corresponding increase in MMP expression, most notably at high glucose concentrations, indicating a potentially renoprotective role in DN.展开更多
文摘BACKGROUND Mizagliflozin(MIZ)is a specific inhibitor of sodium-glucose cotransport protein 1(SGLT1)originally developed as a medication for diabetes.AIM To explore the impact of MIZ on diabetic nephropathy(DN).METHODS Diabetic mice were created using db/db mice.They were administered either a low dose(0.5 mg/kg)or a high dose(1.0 mg/kg)of the SGLT1 inhibitor MIZ via stomach gavage for 8 weeks.Subsequently,mesangial cells(MCs)were isolated and subjected to high glucose conditions in culture to assess the effects of MIZ on DN.RESULTS The results showed that low doses of MIZ significantly reduced albuminuria to a level comparable to that achieved with high doses in db/db mice.High doses of MIZ led to a substantial increase in body weight in mice,along with decreased blood glucose levels and food intake.Moreover,the intervention with high-dose MIZ notably decreased the expression of extracellular matrix genes,such as collagen type 1 alpha 1 mRNA levels.While the expression of SGLT1 increased after exposure to high glucose,it decreased following treatment with MIZ.Furthermore,MIZ intervention was more effective in improving lactate dehydrogenase levels in MCs induced by high glucose compared to canagliflozin.MIZ also significantly elevated levels of antioxidant enzymes superoxide dismutase,catalase,and glutathione,while reducing malondialdehyde levels.CONCLUSION These findings indicate that MIZ can ameliorate DN by inhibiting SGLT1,inflammation,and oxidative stress.
文摘Objective:To investigate the effect of shikonin on the proliferation, apoptosis and extracellular matrix (ECM) of human mesangial cells (MC). Methods: MC was cultured in vitro with different concentrations of glucose (30, 50, 80 mmol/L). The cell growth was observed by using MTT method and apoptosis by using an aunexin-V-Fluos. Immunohistochemical studies for Laminin (LN), Fibronectin (FN) and type Ⅳ Collagens (Col Ⅳ) were measured. Results: Shikonin inhibited their growth (P<0.05) and apoptosis in the glycated cultured cells. Shikonin 0.05 mmol/L significantly reduced the secretion of LN, FN and Col Ⅳ from MC (P<0.05) cultured in 30, 50 and 80 mmol/L glucose. Conclusion: Shikonin could prevent or treat diabetic nephropathy (DN) and glomerulosclerosis (GS).
文摘Objective:To examine whether lipoxin A 4(LXA 4) has an inhibitory effect on tumor necrosis factor-α(TNF-α)-induced proliferation of glomerular mesangial cells of rat, and explore the molecular mechanisms of signal pathway in LXA 4 actions. Methods: Glomerular mesangial cells of rat were cultured and treated with TNF-α(10 ng/ml), with or without preincubation with LXA 4 at different concentrations. Cell proliferation was evaluated by monotetrazolium (MTT) colorimetric assay. The expression of cyclin E mRNA was measured by RT-PCR. Phosphorylated Akt1(Thr308) and p27 kip1 were analyzed by Western blotting. Results: TNF-α-stimulated proliferation of mesangial cells was inhibited by LXA 4 in a dose-dependent manner. The marked increments in cyclin E mRNA expression induced by TNF-α during proliferation of mesangial cells were down-regulated by LXA 4. Threonine phosphorylated Akt1 proteins at 308 site stimulated by TNF-α was reduced by LXA 4. TNF-α-induced decrements in expression of p27 kip1 proteins was ameliorated by LXA 4 in a dose-dependent manner. Conclusion: TNF-α-induced proliferation of rat mesangial cells can be inhibited by TXA 4 through the mechanism of Akt 1/p27 kip1 pathway-dependent signal transduction.
基金National Science and Technology Ninth 5-year Project of Medicine(96-906-05-0)
文摘Objective: To explore the effect of L158, 809 (angiatensin Ⅱ receptorMockers, ARBs) and Cilazapril (Angiotensin converting enzyme inhibitor, ACEI) on the expression oftransforming growth factor-β_1 (TGF-β_1) and secretion of fibronectin, laminin and type Ⅳcollagen from the cultured human mesangial cells . Methods: Human mesangial cells were cultured indifferent glucose (5.6 mmol/L and 30 mmol/L) and agents (1, 10, 100 and 500 μmol/L) concentrations. The proliferation of mesangial cells were detected at 24, 48 and 72 h . Then the mesangial cellsare divided into four groups, low glucose (5.6 mmol/L) control group, high glucose (30 mmol/L)control group , L158, 809 (10 μmol/L) group and cilazapril (10 μmol/L) group. Forty- eight hourslater, the expression of TGF-β_1 were detected by RT-PCR. Concentrations of TGF-β_1 ,fibronection, laminin and type Ⅳ collagen in the su-pematants of the, mesangial cells weredetermined by EUSA and radioimmunoassay methods. Results: Compared with low glucose control group,the mesangial cells under high glucose medium show excessive proliferation and more TGF-β_1,fibronectin, laminin and type Ⅳ collagen in the supernatant. The expression of TGF-β_1 mRNA wasalso significantly increased under high glucose. The levels of TGF-β_1 and ECM (extracellularmatrix) proteins in the L158, 809 group and cilazapril group are obviously lower than that of thehigh glucose control group. The expression of TGF-β_1 mRNA was markedly decreased in the L158, 809group and cilazapril group compared with that of high glucose control group . Conclusion: Highglucose stimulated the cultured human mesangial cells to excessively proliferate, express TGF-β_1and secrete ECM proteins, and the high glucose-indeced changes were suppressed by either L158, 809and cilazapril.
基金a grant from National Natural Science Foundation of China (No. 30772360)
文摘The X gene of HBV encodes a 17-kD protein, termed HBx, which has been shown to function as a transcriptional trans-activator of a variety of viral and cellular promoter/enhancer elements. The aim of this study was to investigate the effect of HBx on gene expression of interleukin （IL）-1β and IL-6, and proliferation of rat mesangial cells in vitro. The X gene of HBV was amplified by PCR assay, and inserted into the eukaryotic expression vector pCI-neo. The structure of recombinant pCI-neo-X plasmid was proved by restrict endonuclease digestion and sequencing analysis. pCI-neo-X was transfected into cultured rat mesangial cell line in vitro via liposome. HBx expression in transfected mesangial cells was detected by Western blot. The IL-1β and IL-6 mRNA expression in those cells was assayed by semiquantitative RT-PCR. Mesangial cell proliferation was tested by MTT. The results showed that HBx was obviously expressed in cultured mesangial cell line at 36th and 48th h after transfection. The expression of IL-1β and IL-6 mRNA was simultaneously increased. The cell proliferation was also obvious at the same time. It was concluded that HBx gene transfection could induce IL-1β and IL-6 gene expression and mesangial cell proliferation. HBx may play a critical role in mesangial cell proliferation through upregulation of the IL-1β and IL-6 gene expression.
基金Supported by Hangzhou Health Technology Project:Study of the Relationship Between Mitofusin 2 And Cyclosporine A Nephropathy(No.2018A52)National Natural Science Foundation of China:Study on Mechanism of Centella Asiatica Compound in the Treatment of Iga Nephropathy by Regulating Mesangial Cell Proliferation via Mitofusin 2(No.81373631)
文摘OBJECTIVE:To investigate the effect of mitofusin 2 (Mfn2) and its downstream signaling pathway on glomerular mesangial cells (GMCs) proliferation in IgA nephropathy (IgAN),as well as the mechanism of action of Jixuecao (Herba Centellae Asiaticae,HCA) in the treatment of IgAN.METHODS:Adenovirus-mediated Mfn2 gene transfection and Mfn2 expression were analyzed by real-time polymerase chain reaction (PCR) and Western blotting.IgA1 induced the proliferation of GMCs,which were then treated with HCA.Cell proliferation was detected with cell counting kit-8 (CCK-8),and Mfn2 expression was analyzed by real-time PCR and western blotting.An IgAN animal model was also established and treated with HCA.GMCs proliferation was detected by hematoxylin-eosin staining,mitochondrial structure was analyzed by electron microscopy,mitochondrial function was determined by the Clark oxygen electrode method,and the expression of Mfn2,Phospho-extracellular regulated protein kinases1/2 (P-ERK1/2),Cyclin-dependent kinase 2 (CDK2),Phospho-p27 (p-p27),and cyclin A was analyzed by Western blotting.RESULTS:In vitro,HCA inhibited GMCs in a concentration-dependent manner in association with the upregulation of Mfn2 expression.The overexpression of Mfn2 inhibited IgA1-induced GMCs proliferation and elevated the effect of HCA.In vivo,treatment with HCA could alleviate albuminuria and creatinine and GMCs proliferation.These effects were related to the upregulation of Mfn2,p-p27 and inhibition of p-ERK1/2,CDK2,and cyclinA.Mitochondrial swelling,vacuolar degeneration,and reduction of respiratory control rate were identified in IgAN,but HCA could improve the mitochondrial structure and function.CONCLUSION:HCA inhibited GMCs proliferation via the upregulation Mfn2 and the inhibition of Ras-Raf-ERK/MAPK.We revealed that changes of mitochondrial structure and function are associated with IgAN,but that HCA can improve these mitochondrial features.
基金This project was supported by grants from the Key Science and Technology Development Program of Nanjing City of the People's Republic of China (No. YKK15057 and No.YKK16097)and the National Natural Science Foundation of China (No.81473684).
文摘Diabetic kidney disease (DKD)is a microvascular complication of type 2 diabetes.The study of DKD mechanisms is the most important target for the prevention of DKD.Renal senescence is one of the important pathogeneses for DKD,but the mechanism of renal and cellular senescence is unclear.Decreased expression of circulating miR-126 is associated with the development of DKD and may be a promising blood-based biomarker for DKD.This study is to probe the effect and mechanism of miR-126 on the aging of human glomerular mesangial cells (HGMCs)induced by high glucose.HGMCs were cultured with Roswell Park Memorial Institute (RPMI-1640)in vitro.The effect of high glucose on morphology of HGMCs was observed 72h after intervention.The cell cycle was examined by flow cytometry.The telomere length was measured by Southern blotting.The expression levels of p53,p21 and Rb proteins in p53-p21-Rb signaling pathway and p-statl,p-stat3 in JAK/STAT signaling pathway were detected by Western blotting respectively.The expression of miR-126 was examined by qRT-PCR.MiR-126 mimics was transfected into HGMCs.The effects of miR-126 mimics transfection on cell morphology,cell cycle,telomere length,p53,p21,Rb,p-stat1 and p-stat3 were observed. The results showed that high glucose not only arrested the cell cycle in G1phase but also shortened the telomere length.High glucose led to high expression of p53,p21,Rb,p-statl and p-stat3 and premature senescence of HGMCs by activating the telomere-p53-p21-Rb and JAK/STAT signaling pathways.Moreover,the miR-126 was decreased in HGMCs induced by high glucose.It was suggested that the transfection of miR-126 mimics could inhibit the telomere-p53-p21-Rb and JAK/STAT signaling pathway activity in vitro and delay the senescence of HGMCs.The results may serve as a new strategy for the treatment of DKD.
基金Supported by Shanghai Municipal Science and Technology Develop-ment Funds (01JC14018).
文摘Objective To study the expressions of MMP-2 and TIMP-2 mRNA on cultured rat mesangial cells (MsC) and in human diseased glomeruli, and to explore their significance in the development of glomerulosclerosis. Methods The expressions of MMP-2, TIMP-2, and Col ⅣmRNA on cultured rat MsC stimulated by IL-1 or/and TGF-β1were investigated through Northern blot analysis. The levels of MMP-2 and TIMP-2 mRNA expressions and immunoreacti-vity of PCNA and Col Ⅳin human diseased glomeruli from renal biopsies of lupus nephritis (LN) patients were examined by insituhybridization and immunohistochemistry, respectively. Results The levels of MMP-2, TIMP-2, and Col ⅣmRNA expressions were markedly increased on cultured rat MsC stimulated by IL-1 or/and TGF-β1. Meanwhile, upregulation of MMP-2 and TIMP-2 mRNA expressions was confirmed in diseased glomeruli from patients with various subtypes of LN, and was closely related to the positive cell number of PCNA presentation and deposition of Col Ⅳin glomeruli. Conclusion The results suggest that the over-expressions of MMP-2 and TIMP-2 mRNA on glomerular cells might play a critical role in the development of glomerulosclerosis.
文摘OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by our laboratory was used to detect the localization of AM protein in rat kidney tissue by avidin-biotin complex immunohistochemistry. The expressions of AM and its receptor CRLR mRNA on cultured glomerular epithelial cells (GEC) and MsC were investigated by Northern blot assay, and the possible effect of AM secreted by GEC on MsC proliferation was observed using [3H]thymidine incorporation as an index. RESULTS: A specific monoclonal antibody against AM was succesfully developed. AM was immunohistochemically localized mainly in glomeruli (GEC and endothelial cells), some cortical proximal tubules, medullary collecting duct cells, interstitial cells, vascular smooth muscle cells and endothelial cells. Northern blot assay showed that AM mRNA was expressed only on cultured GEC, but not on MsC, however, AM receptor CRLR mRNA was only expressed on MsC. GEC conditioned medium containing AM can inhibit MsC growth and AM receptor blocker CGRP8-37 may partially decreased this inhibitory effect. CONCLUSION: AM produced by GEC inhibits the proliferation of MsC, which suggests that AM as an important regulator is involved in glomerular normal physiological functions and pathologic processes.
基金Supported by National Natural Science Foundation of China, No. 30270607
文摘AIM： To delineate the mechanisms of renal vasoconstriction in hepatorenal syndrome （HRS）, we investigated the expression of type I inositol 1, 4, 5-triphosphate receptors （IP3R I） of kidney in mice with fulminant hepatic failure （FHF）. METHODS： FHF was induced by lipopolysaccharide （LPS） in D-galactosamine （GAIN） sensitized BALB/c mice. There were 20 mice in normal saline （NS）-treated group, 20 mice in LPS-treated group, 20 mice in GaIN- treated group, and 60 mice in GalN/LPS-treated group （FHF group）. Liver and kidney tissues were obtained at 2, 6, and 9 h after administration. The liver and kidney specimens were stained with hematoxylin-eosin for studying morphological changes under light microscope. The expression of IP3R I in kidney tissue was tested by immunohistochemistry, Western blot and reverse transcription （RT）-PCR. RESULTS： Kidney tissues were morphologically normal at all time points in all groups. IP3R I proteins were found localized in the plasma region of glomerular mesangial cells （GMC） and vascular smooth muscle cells （VSMC） in kidney by immunohistochemical staining. In kidney of mice with FHF at 6 h and 9 h IP3R I staining was upregulated. Results from Western blot demonstrated consistent and significant increment of IP3R I expression in mice with FHF at 6 h and 9 h （t = 3.16, P 〈 0.05; t = 5.43, P 〈 0.01）. Furthermore, we evaluated IP3R I mRNA expression by RT-PCR and observed marked upregulation of IP3R I mRNA in FHF samples at 2 h, 6 h and 9 h compared to controls （t = 2.97, P 〈 0.05; t = 4.42, P 〈 0.01; t = 3.81, P 〈 0.01）. CONCLUSION： The expression of IP3R I protein increased in GMC and renal VSMC of mice with FHF, possibly caused by up-regulation of IP3R I mRNA.
基金the Science Technology Development Project of Jilin Province, China(No.20020503-2).
文摘The crude polysaccharide was obtained by means of the decolorization of porphyrized Cordyceps minlitaris stroma with organic solvent, extraction with hot water, precipitation in 80% ethanol, and protein removal with the Sevag method. After purification with Sephadex G-75, two of its components, CMP-1 and CMP-2, were obtained. Through the assay of gel chromatography and polarimetry, CMP-1 was identified as pure polysaccharide. The results demonstrated that CMP-1 had favorable oxidation resistance activity, which could scavenge not only oxygen-free radicals in the self-oxidation system of pyrogallic acid, but also the hydroxide-free radicals in the Fenton system. The study focused on the effects of low, medium, and high dosages of CMP-1 in rat blood serum on the proliferation of glomerular mesangial cells in vitro. Through MTT Colorimetric analysis, the activities were compared among the blank control group and the Niaoduqing positive control group CMP-1 and CMP-2. The results shows that CMP-1 was able to inhibit the proliferation of rat glomerular mesangial cells effectively. Therefore, CMP-1, one component of polysaccharides of Cordyceps minlitaris, was certainly a potential remedy for hyperplastic glomerular nephritis, whose antioxidant activity could slow down the process of chronic renal failure（CRF） to some extent.
基金Supported by Monographic Research of Capital Traditional Chinese Medicine(No.3500-11723360)
文摘OBJECTIVE: To investigate the effect of the clinical effective prescription of Qingre Lishi Yishen decoction(QRLS) on the activation of mesangial cells in immunoglobulin A nephropathy(IgAN) rats.METHODS: IgAN rat’s model was established by combine with intragastric administration of bovine serum albumin(BSA) + intravenous injection of lipopolysaccharide(LPS) by + subcutaneous injection of carbon tetrachloride(CCL4). Then the animals were randomly divided into four groups: control group, IgAN model group, IgAN model with Valsartan(Val) treatment group and IgAN model with QRLS treatment group. To observe the indexes of 24-h urine protein, renal function, deposition of immune complexes, expression of activation factor, fibrosis marker and inflammatory cytokines in four different groups.RESULTS: The Val or QRLS treatment group:(a) it reduced the immune complexes deposition of IgA in glomerular mesangial and inhibited mesangial cell proliferation;(b) it decreased the expression of smooth muscle actin(α-SMA), fibronectin(FN) and tumor necrosis factor alpha(TNF-α).CONCLUSION: The study suggested that QRLS ameliorate renal structure and function in IgAN rat’s model. Furthermore, we also observed that QRLS alleviated mesangial cells activation and matrix accumulation partly by decreasing the α-SMA,then to downregulated the expression of FN and TNF-α.
文摘Objective：To investigate the effects of emodin（EMD） on cell proliferation and correlative cytokines secretion of glomerular mesangial in rats. Methods：The effects of EMD on cell proliferation and IL-6, TGF-β1 secretion of glomerular mesangial in rats were observed. Cell proliferation was measured by MTT method. IL-6 and TGF-β1 secretion was detected with ELISA. Results：EMD was able to inhibit the cell proliferation and down-regulate the IL-6 and TGF-β 1 secretion of glomerular mesangial, as compared to the model group in rats （P 〈 0.05）. Conclusion：EMD could significantly inhibit the cell proliferation, and reduce the creation of extracellular matrix（ECM）, this indicated that it could play an important role in alleviation and prevention of glomerular sclerosis. The mechanism may be that EMD can reduce the IL-6 and TGF-β1 secretion ofglomerular mesangial cell in rats.
文摘Interleukin-10(IL-10), a cytokine with anti-inflammatory and immunomodulatory functions, regulates the biology of B and T cells. The present review describes the role of IL-10 in normal renal physiology, during acute kidney injury and in the development of chronic renal failure. We further discuss IL-10-induced cellular and molecular pathways and their link to the progression of kidney injury.
基金a grant from the National Natural Sciences Foundation of China (No. 30600810)
文摘The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 （SD） could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP （FP） under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 （KN） could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.
文摘Summary： To study the efficacy and the mechanism of Colquhoumia root （ Tripterygium hypoglaucure （Le,vL） Hutch） in the treatment of mesangial proliferation glomerulonephritis （MsPGN）, SD rats were injected with anti-thymoeyte serum （ATS） to make MsPGN model （anti-Thyl model）. The rats were then divided into 3 groups： normal control group, anti-Thyl model group and treatment group. Histopathologieal （HE, PAS）, immunohistoehemieal, RT-PCR technique and computer imaging analysis system were used to evaluate mesangial matrix production, the expression of TGF-β protein and mRNA in the tissues of kidney. Our result showed that proteinuria and the ratio of extraeellular matrix/glomerular capillaries area （ECM/CA） were increased significantly in model group. The expression of both TGF-β protein and mRNA in glomeruli was much higher in model group than in control group （P〈0.01）. After the treatment with Colquhoumia root, proteinuria, ECM/CA and the expression of both TGF-β1 protein and mRNA in glomeruli were significantly decreased in treatment group as compared with those in model group. It is concluded that Colquhoumia root is effective in reducing proteinuria and mesangial matrix proliferation in MsPGN and it may achieve these effects by inhibiting the expressions of TGF-β1 protein and mRNA of mesangial cells.
文摘Objective: To examine whether lipoxin A 4 (LXA 4) has an antagonistic effect on IL-1β-induced synthesis of IL-6 in glomerular mesangial cells, and to explore the molecular mechanisms of signal pathway in LXA 4 actions. Methods: The glomerular mesangial cells of rat were cultured and treated with IL-1β, with or without preincubation with LXA 4 at different concentrations. The amount of IL-6 in the supernatant of cells was analyzed by enzyme-linked immunosorbent assay(ELISA). The expressions of mRNA of IL-6 were determined by RT-PCR. The expressions of Src homology 2(SH 2) containing protein-tyrosine phosphatase 2(Shp-2) were assessed by immunoprecipitation and immunoblotting. Activities of DNA-binding of nuclear factor-kappa B(NF-κB) were measured by electrophoretic mobility shift assay(EMSA). Results: IL-1β-stimulated secretion of protein and expression of mRNA of IL-6 in mesangial cells were inhibited by LXA 4 in a dose-dependent manner. LXA 4 antagonizes the phosphorylation of Shp-2 and activities of NF-κB induced by IL-1β. Conclusion: LXA 4 antagonists IL-1β-induced synthesis of IL-6 in glomerular mesangial cells through the mechanism of Shp-2/NF-κB pathway-dependent signal transduction.
文摘Background The pathogenesis of diabetic nephropathy (DN) is a complex pathophysiological process.Its precise mechanism is not fully known. In recent years it has been recognized that synthesis of various extracelluar matrix (ECM) components may increase, and that degradation of ECM may decrease in DN. It was reported heparin could inhibit mesangial cells proliferation in vitro. The main aim of this study is to explore whether heparin inhibits proliferation of mesangial cells grown in high glucose concentration and to measure the effect of heparin on matrix metalloproteinases (MMPs) expression in mesangial cells. Methods The medium contained either low glucose (5 mmol/L) or high glucose (25 mmol/L). The concentrations of heparin in the culture medium were 0, 25, 50,100, 200 or 400 μg/mL. A metabolic (WST-1) assay was used to measure mesangial cell proliferation and Western blot analysis was used to measure MMPs expression of mesangial cells. Results Normal human mesangial cell (NHMC) proliferation was higher in high glucose (HG) medium than in low glucose (LG) medium. They showed a 1.93 fold expansion after 72 h in high glucose in contrast to a 1.63 fold expansion in low glucose. In the presence of heparin, mesangial cells proliferation was inhibited, which was more obvious at high glucose concentrations than at low glucose concentrations. In high glucose, with heparin concentration of 50, 100, 200 and 400 μg/mL, the mesangial cells showed a 0. 61 fold, 0.52 fold, 0.52 fold and 0.41 fold reductions in cell number compared to cells grown without heparin. In low glucose, only concentrations of 200 μg/mL and 400 μg/mL showed reduction in cell number, namely 0.54 fold and 0.45 fold, when compared to cells grown without heparin. In Western blot analysis,MMP1, MMP2, MMP3 and MMP9 was expressed by mesangial cells expressed in both high and low glucose concentrations, which was more prominent in high glucose medium. Incubation of heparin further increased expression of MMP1, MMP2, MMP3 and MMP9. Conclusions This study suggests that glucose can accelerate mesangial cell proliferation while heparin can reduce proliferation, being more obvious at high glucose concentrations. Higher glucose concentrations led to increased MMP expression, which may take part in the regulation of mesangial matrix synthesis and degradation. Addition of heparin resulted in a corresponding increase in MMP expression, most notably at high glucose concentrations, indicating a potentially renoprotective role in DN.
