In vivo and in vitro effects of SREBP-1 on diabetic renal tubular lipid accumulation and RNAi-mediated gene silencing study.

Lipid deposits can injury the kidney of diabetic patients and models. Sterol regulatory element binding protein-1 (SREBP-1) is transcription factor regulating the synthesis of fatty acid and triglyceride. At present whether the expression of SREBP-1 makes some effects on the lipid accumulation in diabetic kidney is not still clear completely. The purpose of our in vivo and in vitro study is to investigate the relationship between the expression of SREBP-1 and lipid abnormal metabolism in the type 1 diabetic rats and explore to inhibit SREBP-1 gene expression by RNA interfere in human renal proximal tubular epithelial cells line (HKC cells). The animal experiment showed that triglyceride and SREBP-1 were up-regulated in proximal tubule of diabetic rats' kidney, which may result in increase of transforming growth factor-beta1 (TGF-beta1) and accumulation of extracellular matrix (ECM). The further HKC cells experiment confirmed SREBP-1 increasing resulted into lipid droplet formation. The expression of fatty acid synthase (FAS) in HKC cells transfected with specific plasmid for SREBP-1 gene was significantly more than that of the cells transfected with the control plasmid pcDNA3.1 and that of the untransfected cells. Simultaneously, up-regulation of TGF-beta1 and fibronectin, an ECM glycoprotein, was evident in HKC cells transfected by specific SREBP-1 plasmid. Furthermore, we found that high glucose was a positive factor on the expression of SREBP-1 at protein and mRNA levels in HKC cells. High glucose makes effects on SREBP-1 in time-dependent manner, and the greatest effect was at 48 h. In addition, two effective eukaryotic expression plasmid vectors of shRNA aimed at SREBP-1 were designed and constructed successfully. Compared with the negative control plasmid group, the levels of the expression of SREBP-1 were inhibited by 24.11 and 36.15%, respectively, at mRNA level, 20.80 and 37.59%, respectively, at precursor segment of protein level, and 38.12 and 52.24%, respectively, at mature segment of protein level at 48 h after transfection. In vivo and in vitro study suggested that high glucose caused increasing SREBP-1 mRNA and protein in renal proximal tubule epithelial cells of type 1 diabetic rats. Increasing SREBP-1 plays an important role in the pathogenesis of renal lipid accumulation by up-regulation of FAS and ECM accumulation by inducing TGF-beta1 expression. The application of vector-mediated RNAi could markedly inhibit the expression of SREBP-1 in HKC cells, which is a promising tool for future research into the mechanisms of renal lipid accumulation in vivo.

Effect of high glucose on cholesterol efflux in renal tubular cell and intervention of anthocyanins / 中国药理学通报

Aim To investigate the effects of high glu-cose on cholesterol metabolism in renal tubular cells and the intervention of the anthocyanins. Methods HK-2 cells were grown in the DMEM medium supple-mented with 10% FBS and were divided into 5 groups:normal glucose group, high glucose group, mannitol group, C3G group and Cy group. Effect of anthocya-nins on cell viability was detected with MTT, and cho-lesterol accumulation was detected with Amplex Red Cholesterol Assay kit and Filipin staining. Expression of ABCA1 was detected with RT-qPCR and Western Blot. Results In compared with control groups, HG significantly promoted cholesterol mass inside the cell and decreased the cholesterol concentration in the me-dium after treatment for 24 h or 48 h. The levels of mRNA and protein of ABCA1 were detected with RT-qPCR and Western blot, and both were decreased in the presence of HG. Whereas treatment with C3G and Cy markedly attenuated HG-induced cholesterol mass inside the cell by up-regulating the expression of AB-CA1. Conclusions High glucose can reduce the ex-pressions of the ABCA1, and then decrease cholesterol efflux and increase the cholesterol accumulation in HK-2 cells. Anthocyanins can decrease cholesterol accu-mulation by up-regulating the expression of ABCA1.

Expression of spliced XBP-1 s and ADRP in kidney of diabetic rats / 临床与实验病理学杂志

Purpose To investigate the expression of XBP-1s and ADRP in kidney of diabetic rats. Methods Diabetic rat models were successfully established by intraperitoneal injection of STZ. After two months rats were sacrificed and XBP-1s and ADRP were de-tected by immunohistochemistry and Western blot. Results XBP-1s and ADRP were located in renal tubular cells and increased by a-bout 2. 017 times and 1. 544 times in comparison with normal control rats (P<0. 05). Moreover, it was shown that high expression of XBP-1s was commonly accompanied with increased ADRP by Pearson correlation analysis and the correlation coefficient was 0. 723 (P<0. 05). Conclusion The increased XBP-1s may cause the up-regulation of ADRP in the kidney of diabetic rats.

Suppressor of cytokine signaling-1 inhibits high glucose-induced expression of monocyte chemoattractant protein-1 in glomerular mesangial cells / 中华肾脏病杂志

Objective To investigate the effect of suppressor of cytokine signaling-1 (SOCS-1)on expression of monocyte chemoattractant protein-1 (MCP-1)in human glomerular mesangial cells (HMCs) under high concentration of glucose. Methods Stable transfections of HMC with pCR3.1 vector and pCR3. 1-SOCS-1 were performed with hpofectamine 2000, and cells were selected with geneticin. Cells were stimulated with low glucose (LG, 5.5 mmol/L), high glucose (HG, 30 mmol/L), LG plus mannitol (24.5 mmol/L) and AG490 (10 μmol/L). The protein expression levels of SOCS-1, signal transducer and activators of transcription 1,3 (STAT1, STAT3),p-STAT1 and p-STAT3 were observed by Western blotting. The protein synthesis of MCP-1, FN and type Ⅳ collagen in the supernatants of the HMCs were detected by ELISA and radioimmunoassay. The expression level of SOCS-1 and MCP-1 mRNA was measured by BT-PCR.Results HG induced the expression of SOCS-1 protein and mRNA in HMCs in time-dependant manner, peaked at 4 h, and gradually decreased to baseline at 24 h. Compared with low glucose control group, the phosphorylation levels of STAT1 and STAT3 and the expression of MCP-1 mRNA [(0.39±0.05) vs (0.16±0.02)]were significantly increased in HMCs under high glucose medium (P ＜0.01 ). Exposure of HMCs to high glucose conditions showed high concentration of MCP-1 [(459±67) ng/L vs (241±19) ng/L], fibronectin [(5.84±0.61) mg/L vs (3.41±0.31) mg/L]and type Ⅳ collagen [(16.45±2.30) μg/L vs (9.56±1.52) μg/L]in the supernatants (all P＜0.01).Overexpression of SOCS-1 inhibited the phosphorylation levels of STAT1 and STAT3 and the expression of MCP-1 mRNA [(0.34±0.04) vs (0.42±0.05)]in HMCs under high glucose condition (all P＜0.05). Compared with vector control group, the concentration of MCP-1 [(387±47) ng/L vs (463±56) ng/L], fibronectin [(4.61±0.57) mg/L vs (5.76±0.74) mg/L]and type Ⅳ collagen [(13.4±2.32) μg/L vs (17.1±2.57) μg/L]was decreased in supernatants of HMCs with SOCS-1 overexpression (all P＜0.05). Compared with HG group, the expression of MCP-1 mRNA (0.31±0.04) and the concentration of MCP-1 [(361±53) ng/L], FN [(5.46±0.71) mg/L]and type Ⅳ collagen [(15.2±1.97) μg/L]in supernatants were decreased in HMCs treated with AG490.Conclusion Overexpression of SOCS-1 inhibits overproduction of MCP-1 and ECM proteins in HMCs under high glucose conditions, which may be partly by regulating the phosphoryhtion of STAT1 and STAT3.

A prospective case-control study of the ERPs in depression / 中华行为医学与脑科学杂志

Objective To explore the event-related potentials (ERPs) P300 is changeable or not before and after treatment. Methods 99 cases of patients with first onset of depression diagnosed by DSM-Ⅳ as case group,and 100 cases matched with patients as control group were collected. P300 of two groups were obtained before and after treatment for 6 weeks,12 weeks,24 weeks. T test was used to analysis the difference of indicators of P300 among groups; repeated measure analysis of variance was used to analysis the longitudinal changes. Results shorter latency of N2-P3 ( (P ＜ 0.01 ); and lower amplitude of N2, P3, N2-P3 (P ＜ 0. 05 ), higher amplitude of P2-tency and a upward one in N2-P3 latency in the four periods; a upward trend could also be found in P3, N2-P3 amplitude, but there were no statistical differences(P ＞ 0. 05 ). The results of paired-samples t test: P3, N2-P3 amplitude in case group were higher after treatment for 6 weeks than before, the difference was significant (P ＜ 0.01 ); no significant results were found in P300 latency or amplitude between the 62 cases of depression after treatment for 24 weeks and the 65 normal controls selected (P ＞ 0. 05 ). Conclusion P300 latencies and amplitudes tend to be partly recovered after the acute treatment in patients with depression, but after the long-term therapy not clear.

Influence of SOCS-1 on AGEs-induced renal tubular epithelial-myofibroblast transdifferentiation / 中国药理学通报

Aim To investigate the effects of suppressor of cytokine signaling-1(SOCS-1)on advanced glycation end products(AGEs)induced-renal tubular epithelial-myofibroblast transdifferentiation and activation of JAK/STAT in cultured human renal tubular epithelial cells(HKC).Methods Stable transfections of HKC with pCR3.1 vector and pCR3.1/SOCS-1 were performed with Lipofectamine 2000,and cells were selected with geneticin.Cells were stimulated with BSA and AGEs. The protein expressions of SOCS-1,α-SMA,E-cadherin,Col I,signal transducer and activatior of transcription 1,3(STAT1,STAT3),p-STAT1 and p-STAT3 were observed by Western blot.The protein synthesis of TGF-β_1 in the supernatants of the HKC was detected by enzyme-linked immunoadsorbent assay(ELISA).α-SMA and E-cadherin mRNA were measured by reverse transcription and polymerase chain reaction(RT-PCR).Results Compared with control group,the expression levels of α-SMA protein and mRNA and Col I were significantly increased in HKC with AGEs stimulation and there was a higher concentrations of TGF-β_1 in the supernatants.However,the expression of E-cadherin protein and mRNA were decreased with AGEs stimulation.Overexpression of SOCS-1 inhibited AGEs-induced activation of STAT1 and STAT3 and high expression of α-SMA protein and mRNA and Col I,and reversed the expression of E-cadherin protein and mRNA induced by AGEs.Meanwhile,overexpression of SOCS-1 reduced the concentration of TGF-β_1 in the supernatants of HKC with AGEs stimulation.Conclusion Overexpression of SOCS-1 inhibits AGEs-induced renal tubular epithelial-myofibroblast transdifferentiation maybe partly through blocking activation of JAK/STAT.

The time-dependent effect of insulin on the expression of SREBP-1,FAS and lipid droplet formation in HKC cells / 中国药理学通报

Aim To investigate the time-dependent effect of insulin on the expression of SREBP-1(sterol regulatory element binding protein-1),FAS(fat acid synthase)and lipid droplet formation in HKC cells(human renal proximal tubular epithelial cells line).MethodsHKC cells were respectively treated with 100 nmol·L~(-1) insulin for 0,2,4,6,12 h and 24 h.The analysis of SREBP-1 and FAS mRNA was performed by RT-PCR and the expression of SREBP-1 protein was detected by Western blot and immunocytochemistry.Furthermore,Oil Red O staining was used to determine cellular lipid droplet formation.ResultsCompared with HKC cells of 0 h group,there was no difference of SREBP-1 and FAS mRNA in HKC cells of 2 h group.However,the expression of SREBP-1 and FAS mRNA was significantly increased in HKC cells of 4,6 h and 12 h group.Further,the most expression of SREBP-1 and FAS mRNA was at 6 h group and was respectively increased by 3.578 and 4.272 times compared with 0 h group.The results of Western blot showed that the precursor and mature segments of SREBP-1 protein in 4,6 h and 12 h group HKC cells were increased and those of 6 h group HKC cells were the highest and about 4.106 and 5.167 times than those of 0 h group HKC cells.Immunocytochemistry presented the result that SREBP-1 protein was located in the plasma and the expression of 4,6 h and 12 h group HKC cells was significantly higher than that of 0,2 h and 24 h group HKC cells.The result of Oil Red O staining showed that lipid droplet markedly deposited in 6 h group HKC cells,contrarily,no lipid droplet was found in HKC cells of other groups.ConclusionAbove results suggested that insulin up-regulated SREBP-1 and FAS in time-dependent manner that led to cellular lipid droplet deposit,which may play an important role in the pathogenesis of renal lipid accumulation in metabolism syndrome.

High glucose stimulates the expression of transforming growth factor-β1 and fibronectin via SREBP-1 in HKC cells / 中华内分泌代谢杂志

significantly increased (all P < 0.01). Following SREBP-1 was down-regulated by siRNA, high glucose-stimulated TGF-β1 and FN protein expressions were decreased by 17.9% and 24.6% ,respectively(all P<0.01).

Modulation of Wnt/β-catenin signaling pathway by irbesartan in highglucose-induced tubular epithelial-mesenchymal transition / 中国药理学通报

Aim To investigate the effects of irbesartan on Wnt/β-catenin signaling pathway in tubular epithelial-mesenchymal transition(EMT)in HKCs induced by high-glucose.Methods Human kidney proximal tubular epithelial cell line(HKCs)cultured in vitro was divided into four groups:normal-glucose group,mannitol control group,high-glucose group and high-glucose plus irbesartan group.Immunocytochemistry staining was used to observe the expression of β-catenin;the protein expression of Wnt4,β-catenin,E-cadherin and α-SMA was assessed by Western blot;Wnt4 and β-catenin mRNA were detected by reverse transcription-polymerase chain reaction(RT-PCR).Results Compared with normal-glucose and mannitol control group,both the protein and the mRNA of Wnt4 were up-regulated in HKCs stimulated by high-glucose.α-SMA expression significantly increased but E-cadherin decreased in HG group.The cytoplastic and nuclear fraction of β-catenin enhanced with highglucose stimulation.But no difference of the total protein and mRNA of β-catenin was observed between highglucose-treatment and control groups.Highglucose induced Wnt4 and β-catenin expression in a time-dependent manner,both peaking at 24 h.Irbesartan reduced the promotional effect of HG on Wnt4 and α-SMA expression,and nuclear translocation of β-catenin.HG-mediated inhibition of E-cadherin was also restored by irbesartan.Conclusion These data supported a functional role for Wnt/β-catenin signaling pathway during epithelial-mesenchymal transition of HKCs induced by high glucose and suggested that irbesartan might reverse tubular EMT by regulating activity of Wnt/β-catenin pathway.

Effect of rosiglitazone on SREBP-1 and TGF-β1 expressions and accumulation of ECM in renal tubular cells of Wistar rats treated with high fat diet / 中国病理生理杂志

AIM: To study the effect of high fat diet on the expression of sterol regulatory element biding protein-1 (SREBP-1) and transforming growth factor β_1 (TGF-β_1) in renal tubular cells and rosiglitazone intervention. METHODS: Wistar rats were treated with high fat diet and rosiglitazone for 3 months. The serum glucose, serum insulin and serum triglyceride were detected. Oil Red O staining was used to observe the renal lipid deposit and Masson staining was for the detection of ECM accumulation. SREBP-1, TGF-β_1 and FN protein were determined by the methods of immunohistochemistry and Western blotting. SREBP-1 mRNA was detected by in situ hybridization. RESULTS: Rosiglitazone prevented effectively the increase in serum glucose, serum insulin and serum triglyceride resulted from high fat diet. High fat diet led to lipid droplet formation in renal tubular cells and interstitial ECM accumulation, which was decreased by rosiglitazone treatment. Compared to normal rats, SREBP-1 protein and SREBP-1 mRNA showed high expressions in high fat diet rats that were lowered by rosiglitazone. The precursor segment and mature segment of SREBP-1 protein were decreased by 27.39% and 27.32%. Similarly, the high expressions of TGF-β_1 and FN protein in kidney of high fat diet rats were also prevented by rosiglitazone intervention. Compared to high fat diet rats, the expression of TGF-β_1 in rosiglitazone treatment rats was lowered by 19.14%. CONCLUSION: Rosiglitazone prevents effectively the over-expression of SREBP-1 and TGF-β_1 in renal tubular cells, and decreases lipid accumulation and ECM production in rats fed with high fat diet.

The effect of HMGB1 on the renal injure of systemic lupus erythematosus mediated in part via the TLR4 pathway / 中华微生物学和免疫学杂志

Objective To investigate the relationship between the effect of high mobility group protein box 1 (HMGBI) on the renal injure of systemic lupus erythematosus (SLE) and the expression of Toll-like receptor 4(TLR4). Methods The level of HMGB1, MMP-2 and TIMP-2 in serum from 16 pa-tients with SLE, 18 patients with lupus nephritis(LN) and 12 healthy people were measured by ELISA. The fresh peripheral blood mononuelear cell (PBMC) were isolated and the total RNA was extracted. Then the mRNA expression of HMGB1 was amplified by RT-PCR. Flow cytometry analysis was performed to study cell surface markers and the expression of TLR4. Results RT-PCR and ELISA results showed that the expres-sions of mRNA and level of HMGB1 protein in serum were higher in patients with LN than those in SLE and healthy people. The expression of TLR4 in CD14+ monecytes of patients with LN was higher than that with SLE and healthy people, while there were no significance in CD3+ T cells among LN, SLE and healthy peo-ple. The expressions of MMP-2 and TIMP-2 in serum of LN was lower than that in SLE and healthy people, at the same time the ratio of MMP-2/TIMP-2 decreased in LN group. HMGB1 mRNA and CD14+/TLR4+ was negatively correlated with the ratio of MMP-2/TIMP-2, and the level of HMGB1 in serum was positively correlated with proteinuria, while negatively correlated with the ratio of MMP-2/TIMP-2 in LN. Conclusion HMGB1 is one of the important cytokine in the pathogenesis of lupus nephritis. HMGBI might play a role in proteinuria of lupus nephritis in part via TLR4 pathway to activate monocytes and decrease the expression of MMP-2/TIMP-2.

Expression of p-Smad2/3 and smad7 in experimental renal tubulointerstitial fibrosis rat model / 基础医学与临床

Objective To examine the expression of TGF-?1/Smads signaling pathway in renal tubulointerstitial fibrosis.Methods Male SD rats were divided into control,sham operation and tubulointerstitial fibrosis groups.They were sacrificed at day 3,7,14,28 after operation.Use masson coloration to examine the area of pathological changes.The level of TGF?1,p-Smad2/3 and smad7 protein was examined by immunohistochemistry staining and Western blot.The level of TGF-?1 mRNA and smad7 mRNA was analyzed by RTPCR.Results Compared with sham operation group,TGF-?1 and p-Smad2/3 were significantly increased in UUO rats,while smad7 protein reduced in it.The mRNA of TGF-?1 and smad 7 increased from day 3 to day 28.Smads protein plays an important role in the synthesis and accumulation of extracellular matrix in tubulointerstitial area.The reduction of smad 7 protein may be a major cause of the interstitial fibrosis in this model.Conclusion TGF-? /Smads protein pathway perhaps is essential in the development of tubulointerstitial fibrosis.

Effects of high glucose on the expression of cytokines in renal proximal tubular epithelial cells in vitro / 基础医学与临床

Objective To investigate the effect of high glucose on the expression of transforming growth factor-?1(TGF-?1),?-SMA,E-Cadherin in renal proximal tubular epithelial cells(HKCs)and role of AG490,an antagonist of Janus kinase.Methods Cultured HKCs cells were divided into four groups:low glucose group(LG),high glucose group(HG),high mannitol group(LG+M),and HG+AG490 group(AG).Immunoprecipitation and Western blot analysis were used to measure the expressions of tryosine phosphorylated Janus kinase 2(p-JAK2),STAT1,STAT3,p-STAT1,p-STAT3 and ?-SMA,E-Cadherin.The contents of TGF-?1 and type I collagen in the supernatants of the cultured HKCs were detected by ELISA.TGF-?1 mRNA were measured by RT-PCR.ResultsCompared with low glucose control group,the expressions of JAK2,p-STAT1,p-STAT3 and TGF-?1 mRNA were significantly increased in HG group from 6 to 72 h.Meanwhile,the contents of TGF-?1 and collagen I in the supernatants and the expression of ?-SMA were increased,the expression of E-Cadherin was decreased.The expression of JAK2,p-STAT1,p-STAT3 and TGF-?1 mRNA and the level of TGF-?1,collagen I in the supernatant s in HG+AG490 group were obviously lower than those of the HG group.The expression of ?-SMA and E-Cadherinwas also decreased in HG+AG490 group.Conclusion Activation of JAK/STAT signaling pathway seems to be involved in the high glucos induced overproduction of TGF-?1 and ECM proteins in HKCs.

Rapamycin inhibits activation of STAT3 in renal tissue of IgA nephropathy rats / 基础医学与临床

Objective To investigate the effects of rapamycin on p-JAK2,STAT3,p-STAT3 and PCNA in ranal tissue of IgAN rats.Methods The animal models of IgA nephropathy were devided into control group,IgAN model group,losartan group and rapamycin group.The clinical efficacy of rapamycin,and its influences on the protein and mRNA expressions of STAT3,p-STAT3,p-JAK2 and PCNA were determined by western blot,RT-PCR and immunohistochemical techniques respectively.Results The protein and mRNA expressions of p-STAT3,STAT3,p-JAK2 and PCNA were significantly increased in kidney of IgAN rats(P

Proliferation of renal cells involved by NF-?B/COX-2 signal pathway in diabetic nephropthy / 基础医学与临床

Objective To investigate the correlation between NF-?B/COX-2 signal pathway and cell proliferation in diabetic nephropathy. Methods Uninephrectomized STZ-induced male Wister rats were used as animal model. Using immunohistochemistry to detect NF-?B and COX-2 protein expressions in diabetic kidneys at the 16th week. HKC were cultured separately in normal or high glucose medium for 24,48,72 h.The expression of NF-?B and COX-2 protein was detected by flow cytometry and the expression of PCNA was detected by immunocytochemical staining. Results 1 Volum of glomeruli, mesangial matrix, thickness of glomerular and tubular basement membrane increased in diabete group; 2 COX-2 were expressed in cytoplasm of tubules and glomeruli by immunohistochemistry. Compared with control group, the expression of COX-2 was higher; activated NF-?B expressed in nucli of both tubules and glomeruli, There was light stainings for in control group, while enhanced stainings were observed in DM, there was a positive correlation between NF-?B and COX-2.3 Compared with those in HKC cultured in the medium with normal level glucose, the stainings were strengthened for PCNA in HKC exposed to high glucose from 24 h. 4 By FCM, the expression of NF-?B and COX-2 in HKC cultured in high glucose medium was higherthan that in normal glucose medium; the expression of NF-?B and PCNA was positively correlated with the expression of COX-2. Conclusion Activating NF-?B and elevating the expression of COX-2 play an important role in regulating cell proliferation, which may be one of the injury mechanisms of the renal cells during diabetic nephropathy.

Expression of ADM and ET-1 was decreased by Losartan in renal of diabetic rats / 基础医学与临床

Objective To investigate the therapeutic effect of Losartan on ADM,ET-1 and their receptors in the kidney of diabetic rats.Methods Experimental diabetes was induced in uninephrectomized rats by STZ.The animals were divided into three groups: group A(control group),group B(diabetic group) and group C(Losartan-treated group).Immunohistochemistry,Western bloting,in situ hybridyzation and RT-PCR were used to detect the protein and mRNA expressions of ADM,ADMR,ET-1 and EDNR-A.Results Compared with group A,the expressions of ADM,ADMR,ET-1 and EDNR-A in group B significantly increased.After Losartan treatment,those indicators decreased.Conclusion The expressions of ADM,ET-1 and their receptors may be responsible for the renal protective effect of Losartan in diabetic rats.

JAK/STAT pathway activation is involved in high glucose-induced transdifferentiation in renal proximal tubular epithelial cells / 中国病理生理杂志

AIM: To investigate the effect of activation of JAK/STAT signaling pathway on the transdifferentiation induced by high concentration of glucose in renal proximal tubular epithelial cells(HKCs).METHODS: Cultured HKCs cells were divided into four groups: low glucose group(LG),high glucose group(HG),high mannitol group(LG+M),and HG+AG490 group(AG).Immunoprecipitation and Western blotting analysis were used to determine the expression of tryosine phosphorylated Janus kinase 2(p-JAK2).The protein expressions of STAT1,STAT3,p-STAT1 and p-STAT3 and expressions of ?-SMA,E-cadherin were observed by Western blotting.The contents of TGF-?1 and type I collagen in the supernatants of the cultured HKCs were detected by enzyme-linked immunoadsorbent assay(ELISA).TGF-?1 mRNA were measured by reverse transcription and polymerase chain reaction(RT-PCR).RESULTS: Compared with low glucose control group,the expression of JAK2,p-STAT1,p-STAT3 and TGF-?1 mRNA was significantly increased in HG group at different stimulated time from 6 h to 72 h.Meanwhile,the contents of TGF-?1 and collagen I in the supernatants and the expression of ?-SMA were increased,the expression of E-cadherin were decreased.The expression of JAK2,p-STAT1,p-STAT3 and TGF-?1 mRNA and the levels of TGF-?1,collagen I in the supernatants in HG+AG490 group were obviously lower than those in HG group.The expressions of ?-SMA and E-cadherin were also decreased in HG+AG490 group.CONCLUSION: Activation of JAK/STAT signaling pathway may be involved in the high glucose-induced transdifferentiation and overproduction of TGF?1 and ECM proteins in HKCs.

Effects of losartan on apoptosis and expression of Fas and Fas-L in the kidney of diabetic rats / 中华肾脏病杂志

Objective To investigate the effects of angiotensin II type I receptor antagonist losartan on apoptosis and the expression of Fas and Fas-L in the kidney of diabetic rats. Methods Uninephrectomized, STZ(65 mg/kg) -induced diabetic male SD rats were used. Losartan(40 mg/kg) was delivered daily by gavage from the next day of the induction to diabetes for 12 weeks. Apoptosis was examined by means of terminal-deoxynucleotidyl transferase mediated d-UTP nick end labeling(TUNEL) . Flow cytometry and immunohistochemistry were used to detect the expression of Fas and Fas-L. Results Compared with those in the kidneys of control group, apoptotic cells were more in number and the expression of Fas and Fas-L was higher in the diabetic kidneys( P

Effect of phosphorylating-p38 mitogen-activated protein kinase on restructuration of extracellular matrix of diabetic glomeruli / 解放军医学杂志

Objective To study the expression and significance of the p38 mitogen-activated protein kinase (MAPK) and cAMP-responsive element binding protein (CREB 1) in experimental diabetic mellitus rats, and their relationship with extracllular matrix (ECM) restructuration. Methods Sixty male Wistar rats, with their kidneys removed surgically, were divided in two groups: control group (n=30) and diabetic group (n=30). Diabetic model was reproduced by intraperitoneal injection of Streptozocin (STZ, 65mg/kg). Six rats of each group were sacrificed at 1, 2, 4, 8 and 12weeks after STZ injection. Immunohistochemistry was used to assess the expression of p-p38 MAPK and p-CREB 1 in both control and diabetic groups. Western blot was performed to determine the activity of p-p38 MAPK and p-CREB 1 in both groups. Semiquantitative competitive reverse transcription polymerase chain reaction (PCR) was performed to detect the expression of mRNA of p38 MAPK, CREB 1 and fibronectin (FN). Results Compared with the control group, expression of p-p38 MAPK in diabetic glomeruli was significantly enhanced at 1, 2, 4, and 8 weeks, then it lowered at 12 weeks. P-CREB 1 was increased at 2, 4, 8 weeks, also decreased at 12 weeks. Elevation of FN mRNA began after 4 weeks in diabetic rats. Conclusions Glomerular p38 MAPK activity was increased in early stage of diabetes. This activated p38 MAPK pathway in diabetic glomeruli may in part play a role in the pathogenesis of extracellular matrix restructuring.

Expression of SREBP-1 in kidney of type 1 diabetic rats and insulin intervention / 中国药理学通报

Aim To investigate the expression of SREBP-1(sterol regulatory element binding protein-1) in the kidney of type 1 diabetic rats and the effect of insulin.Methods The type 1 diabetic models were induced by high dose of STZ and rats were randomly divided into three groups: normal control group,diabetes control group and insulin treated group.At the 2nd week end,the triglyceride(TG) content in the kidney of experimental rats was measured by the assay kit and oil Red O staining.Furthermore,the expression of SREBP-1 protein was detected by the methods of Western blot and immunohistochemistry.The analysis of SREBP-1 mRNA was performed by in situ hybridization.Results Compared with the control group,the type 1 diabetic rats' renal triglyceride content markedly increased,and the result of Oil Red O showed that lipid deposited in the renal tubular epithelium.Triglyceride content markedly decreased after insulin treatment.The difference had statistic meaning,compared with the diabetes model group.Immunohistochemistry presented the results that SREBP-1 protein was up-regulated in renal tubular epithelium of diabetic rats and insulin treatment suppressed the increasing.The results of western blot showed that the precursor and mature segments of SREBP-1 protein in kidney of diabetes group rats were about 1.86 times and 1.77 times respectively of that of normal control group rats.In situ hybridization confirmed the increasing of SREBP-1 mRNA in renal tubular epithelium in diabetic rats.The effect of insulin treatment on SREBP-1 expression was detected by the methods of Western blot and in situ hybridization and it was found that the SREBP-1 mRNA and protein of kidney were down-regulated.Compared with the normal group,the difference has statistic meaning(P