Puerarin reduces increased c-fos, c-jun, and type Ⅳ collagen expression caused by high glucose in glomerular mesangial cells

Aim: Increased expression of c-fos, c-jun and type Ⅳ collagen (CoⅣ) in glomerular mesangial cells (GMC) are important characteristics of diabetic nephropathy. Both c-los and c-jun regulate the gene expression of extracellular matrix components, and CoⅣ is the main component of the extracellular matrix. It has been reported that puerarin inhibits aggregation of the extracellular matrix in diabetic rats by an as yet unknown mechanism. The aim of this study is to investigate the effect of puerarin on c-fos, c-jun and CoⅣ expression in GMC cultured in medium containing 5.6 or 27.8 mmol/L glucose. Methods: The expressions of c-fos and c-jun were measured at the protein level using flow cytometry. CoⅣ content was detected using radioimmunoassay. Protein kinase C (PKC) activity was measured using liquid scintillation counting. Results: Puerarin (10-5mmol/L) significantly ameliorated the high-glucose effect on c-fos, c-jun and CoⅣ expression. This effect is accompanied by a reduced PKC activity in these cells. Coclusion: Our results suggest that reduced PKC activity and expression of c-fos and c-jun in GMC might participate in the mechanisms underlying the therapeutic effect of puerarin on diabetic nephropathy.