The Mechanism Of 1,25（OH）₂D₃ Regulating MiR-130b,PAI-1,Col-Ⅳ Via TGF-β1 Influencing Renal Fibrosis In Diabetic Nephropathy Rats

Objective:Preliminary study to investigate whether 1,25（OH）₂D₃ has an effect on the expression of miR-130b in the kidney of diabetic nephropathy rats,and does 1,25（OH）₂D₃ may affect the expression of miR-130b,PAI-1,Col-Ⅳ by regulating TGF-β1 to improve the process of diabetic nephropathy and renal fibrosis.Methods:Preliminary study established the Normal control group,Diabetic nephropathy+1,25（OH）₂D₃ group,Diabetic nephropathy+peanut oil group rat model.TGF-β1 overexpression+peanut oil group,TGF-β1 overexpression+1,25（OH）₂D₃ group,TGF-β1 low-expression+peanut oil group,TGF-β1 low-expression+1,25（OH）₂D₃ group diabetic nephropathy rat model were involved in further discussion.Calctriol（1,25（OH）₂D₃,active vitamin D3;0.03ug/（kg·d））treatment,peanut oil control.Blood glucose,24-hour urinary microalbumin,BUN,SCr,TC,TG were measured after the samples were collected.Quantitative Real-time polymerase chain reaction（qRT-PCR）was used to detect the expression level of miR-130b in rat kidney.qRT-PCR,Western Blot and immunohistochemical methods were used to detect the expression levels of TGF-β1,PAI-1 and Col-Ⅳ in rats.HE and Masson staining were used to analyze the morphological structure and degree of fibrosis of rat kidney.One-way ANOVA and t test were used to compare the data of each group.Results:1)Diabetic nephropathy+1,25（OH）₂D₃ and diabetic nephropathy+peanut oil group rats blood glucose,24h urine trace albumin,BUN,SCr,TC,TG levels were significantly higher than the normal control group（P<0.05）,diabetic nephropathy+1,25（OH）₂D₃ group rats blood glucose,24h urine trace albumin,BUN,SCr,TC,TG levels were significantly lower than that of diabetic nephropathy+peanut oil group（P<0.05）.qRT-PCR results showed that the expression level of miR-130b in diabetic nephropathy+1,25（OH）₂D₃group and diabetic nephropathy+peanut oil group were significantly lower than that in the normal control group（P<0.05）,while the expression level of miR-130b in diabetic nephropathy+1,25（OH）₂D₃ group was significantly higher than diabetic nephropathy+peanut oil group（P<0.05）.qRT-PCR,Western Blot,immunohistochemistry and pathological results showed that diabetic nephropathy+1,25（OH）₂D₃ and diabetic nephropathy+peanut oil group in the rat kidney TGF-β1 mRNA and protein expression level,the structure of the kidney tissue disorders and fibrosis were significantly higher than that of normal control group（P<0.05）,diabetic nephropathy+1,25（OH）₂D₃ group was obviously lower than that of diabetic nephropathy+peanut oil group（P<0.05）;2)Serum glucose,24h urinary microalbumin,BUN,SCr,TC,TG levels of diabetic nephropathy rats in the TGF-β1 overexpression group were significantly higher than those in the TGF-β1 low-expression group（P<0.05）.After treatment with 1,25（OH）₂D₃,the serum glucose,24h urinary microalbumin,BUN,SCr,TC,TG levels were significantly lower（P<0.05）.qRT-PCR results showed that the expression level of miR-130b in diabetic nephropathy rats in the TGF-β1 overexpression group was significantly lower than that in the TGF-β1 low-expression group（P<0.05）.After treatment with1,25（OH）₂D₃,the expression level of miR-130b was significantly increased（P<0.05）.qRT-PCR,Western Blot and immunohistochemistry and pathological results showed that TGF-β1 overexpression group of diabetic nephropathy rats kidney TGF-β1,PAI-1,Col-Ⅳ mRNA and protein expression level obviously higher than that of TGF-β1 low-expression group（P<0.05）,pathology showed the organization structure and disorder of kidney the more serious in TGF-β1 overexpression group,after treatment with 1,25（OH）₂D₃,TGF-β1,PAI-1,Col-Ⅳ mRNA and protein expression level decreased obviously（P<0.05）,significantly improve kidney structure and the degree of fibrosis.Conclusion:1)1,25（OH）₂D₃ has an effect on the expression of miR-130b,TGF-β1 and renal fibrosis in diabetic nephropathy;2)The expression level of TGF-β1 in the kidney of diabetic nephropathy rats has a negative regulatory effect on the expression of miR-130b,and a positive regulatory effect on the expression levels of PAI-1 and Col-Ⅳ.1,25（OH）₂D₃ may upregulate the expression of miR-130b and reduce the expression levels of PAI-1,Col-Ⅳ by TGF-β1 to improve the process of diabetic nephropathy and kidney fibrosis.