Renal Protective Effects Of 1, 25-Dihydroxyvitamin D₃ On Rats With Streptozotocin Diabetes And Its Mechanism

Objective To explore the effects of 1,25-dihydroxyvitamin D3 on renal morphology and renal function of rats with streptozotocin diabetes.Methods Sprague-Dawley rats were randomized into 3 groups:normal control rats(group NC),streptozotocin(STZ) induced diabetic rats(group DM ) and diabetic rats treated with 1,25-dihydroxyvitamin D3 (group DC).Mean glomerular volume(MGV),kidney-to-body weight ratio(KW/BW),24h urinary protein excretory ratio(UPE) and serum creatinine(Scr) were measured after 12 weeks of treatment , while transforming growth factor- beta1(TGF-β1),nuclear factor–kappa B(NF-κB),monocyte chemoattractant protein-1(MCP-1),CD68,expression in kidney cortex were observed by immunohistochemistry.The expression levels of TGF-β1,NF-κB,MCP-1 were detected by Reverse transcription and polymerase chain reaction(RT-PCR) at the end of the experiment.Results 24hUPE,Scr,MGV and KW/BW ratio were significantly higher in the diabetic rats than those in the normal control group(P<0.01).The expression levels of TGF-β1,NF-κB,MCP-1,CD68 in the diabetic rats were also significantly higher as compared with those in the normal control group (P<0.01).24hUPE,Scr,MGV,KW/BW ratio and the levels of TGF-β1,NF-κB,MCP-1,CD68 in the 1,25-dihydroxyvitamin D3 -treated group were obviously lower than those in the diabetic rats (P<0.01).Conclusion 1 , 25-dihydroxyvitamin D3 can protect rats with streptozotocin diabetes from diabetic nephropathy by suppressing the Over expressions of TGF-β1,NF-κB,MCP-1 in renaI cortex ,inhibition macrophage infiltration in the diabetic kidney.