ABSTRACT
Objective:To investigate the effects of 3-methyladenine(3-MA)on extracellular matrix deposition in early diabetic nephropathy(DN)and its mechanism.Methods:A streptozotocin(STZ)-induced type 1 diabetes mouse model was used, and the mice were divided into vehicle control group, diabetes group(STZ group), 3-MA group, and chloroquine(CQ)group, 8 mice in each group. After 6 weeks of intervention, both kidneys were harvested, and the kidney-to-body weight ratio was recorded. Western blotting was performed to detect protein expressions of renal cortex fibronectin, α-smooth muscle actin(α-SMA), LC3, Beclin 1, p62, and vascular endothelial growth factor(VEGF). Immunohistochemistry was used to observe kidney fibronectin staining. Bioinformatics analysis was conducted on shared genes between diabetic nephropathy(DN)gene targets and 3-MA predicted gene targets.Results:Both 3-MA and CQ exhibited certain hypoglycemic effects in diabetic mice. Compared to the STZ group, the kidney-to-body weight ratio decreased in the 3-MA group( P<0.05). Western blotting showed that 3-MA reduced the expression of renal cortex matrix-related proteins fibronectin and α-SMA in diabetic mice( P<0.05 or P<0.01). Immunohistochemistry also revealed that 3-MA reduced fibronectin staining in the kidneys of diabetic mice. Both 3-MA and CQ inhibited the protein expression of renal cortex Beclin 1 in diabetic mice(both P<0.05), while 3-MA increased the expression of renal cortex p62( P<0.05). Bioinformatics analysis indicated a connection between shared genes of DN gene targets and 3-MA predicted gene targets with the VEGF signaling pathway. Western blotting results further showed that 3-MA reduced renal cortex VEGF expression in diabetic mice( P<0.01). Conclusion:3-MA can alleviate extracellular matrix deposition in the kidneys of early DN mice by inhibiting the VEGF signaling pathway.