The Role And Mechanism Of Hsp90 In Diabetic Nephropathy In Rats

Objective: To investigate the expression of heat shock protein 90 in the kidney of diabetic nephropathy rats and its possible role in diabetic nephropathy.Methods:Animal models of diabetic rats were established by intraperitoneal injection of streptozotocin in animal experiments.The animals were divided into normal control group and diabetic non-diabetic nephropathy group(urine albumin elevation 2 times)by urine protein level and blood glucose detection monitoring.The following)and diabetic nephropathy(urinary albumin elevation more than 10 times,AMDC criteria)group.PAS staining was used to evaluate the pathological changes of renal tissues.Immunofluorescence was used to detect the expression of e NOS,Caveolin-1,Hsp90?,and Hsp90? in glomeruli.Western blot and real-time q PCR were used to detect e NOS in glomeruli.The protein and m RNA expressions of Caveolin-1,Hsp90? and Hsp90? were detected by co-immunoprecipitation.The levels of e NOS,caveolin-1,e NOS and Hsp90?/?were detected by Western blotting.The expression of e NOS Ser1177 phosphorylation protein in each group was detected by Western Bolt assay.Nitric Oxide Assay Kit was used to determine e NOS activity.Results:The histopathological staining of renal tissues in each group showed that compared with the normal control group and the diabetic group,the glomeruli in the diabetic nephropathy group were generally hypertrophic and the mesangial matrix increased significantly;compared with the normal control group,the diabetic group had glomeruli No significant hypertrophy,no significant increase in mesangial matrix.Immunofluorescence histochemical staining showed that there was no significant difference in the immunofluorescence intensity of e NOS,Caveolin-1,Hsp90?,and Hsp90? in each group of glomeruli.There was no significant change in m RNA expression of e NOS,Hsp90?,and Hsp90? in glomeruli in each group.There was no significant difference in the expression of e NOS,Caveolin-1,Hsp90? and Hsp90? in the glomeruli by Western Bolt.Compared with the normal control group and the diabetic group,the protein expression level of e NOS ser1177 wassignificantly decreased in the diabetic nephropathy group.Compared with the diabetic group,the expression level of e NOS ser1177 in the glomerulus was not significantly changed in the normal control group.Co-immunoprecipitation assays showed that the interaction between e NOS and Caveolin-1 in the normal control group and the diabetic group was significantly increased compared with the diabetic nephropathy group;the interaction between e NOS and Caveolin-1 in the normal control group and the diabetic group was not significantly changed;There was no significant difference in the interaction between e NOS and Hsp90?in normal control group,diabetic non-diabetic nephropathy group and diabetic nephropathy group.Compared with diabetic nephropathy group,the interaction between e NOS and Hsp90? in the normal control group and diabetic group was significantly weakened;There was no significant change in the interaction between e NOS and Hsp90? in the diabetic group.The results of NOS typing showed that the activity of e NOS was significantly lower in the diabetic nephropathy group than in the normal control group and the diabetic group.The activity of e NOS was not significantly changed in the normal group and the diabetic group.Conclusions : In early diabetic nephropathy,Hsp90? may reduce the interaction between e NOS and Caveolin-1 by decreasing the interaction with e NOS,or decrease the level of e NOS Ser1177 phosphorylation protein through the PI3K/Akt pathway.