Influence of miR-155-5p on renal fibrosis in rats with diabetic kidney disease by targeting silent information regulator 1 to regulate transforming growth factor-β/Sma-and Mad-related protein signaling pathway
Objective To explore the influence of miR-155-5p on renal fibrosis in diabetic kidney disease(DKD)rats by targeting silent information regulator 1(SIRT1)/transforming growth factor-beta/Sma-and Mad-related protein(TGF-β/Smad)signaling pathway.Methods Forty-eight rats were randomly divided into normal control(NC)group,model(Mod)group,inhibitor negative control(anti-NC)group,miR-155-5p inhibitor(anti-miR-155-5p)group,miR-155-5p inhibitor+small interfering RNA negative control(anti-miR-155-5p+si-NC)group,and miR-155-5p inhibitor+SIRT1 small interfering RNA(anti-miR-155-5p+si-SIRT1)group,with 8 rats in each group.FPG,24 h UAlb,BUN and serum creatinine(Scr)were detected in each group.HE and Masson staining were used to compare the pathological changes of renal tissue in each group,and the collagen volume fraction(CVF)was calculated.The mRNA expressions of miR-155-5p and SIRT1 were detected by real-time fluorescence quantitative PCR(RT-qRCR),and the protein expressions of SIRT1,TGF-β1,Smad3,Smad7,connective tissue growth factor(CTGF)and collagen type Ⅰ(COLⅠ)were detected by Western blot.Results Compared with NC group,the expressions of FPG,24 hUAlb,BUN,Scr,CVF,miR-155-5p,TGF-β1,Smad3,CTGF and COLⅠincreased(P<0.05),while the expressions of SIRT1 mRNA and protein and Smad7 protein decreased in Mod and anti-NC groups(P<0.05).Compared with the anti-NC group,in the anti-miR-155-5p,anti-miR-155-5p+si-NC groups,the expression of SIRT1 mRNA and protein,Smad7 protein increased(P<0.05),and FPG,24 hUAlb,BUN,Scr,CVF,miR-155-5p,TGF-β1,Smad3,CTGF and COLⅠprotein were expressed(P<0.05).Compared with the anti-miR-155-5p and anti-miR-155-5p+si-NC groups,the anti-miR-155-5p+si-SIRT1 group showed the expression of FPG,24 hUAlb,BUN,Scr,CVF,miR-155-5p,TGF-β1,Smad3、CTGF、and COLⅠprotein increased(P<0.05),the expression of SIRT1 mRNA and protein,Smad7 protein decreased(P<0.05).The 3'UTR of SIRT1 mRNA contains the conserved base of miR-155-5p sequence.Conclusions Elevated miR-155-5p in DKD rats can target and regulate SIRT1 to alleviate the process of renal fibrosis.
miR-155-5pSilent information regulator 1Transforming growth factor-β/Sma-and Mad-related protein signaling pathwayDiabetic kidney diseaseRenal fibrosis