The protective effect of asiatic acid on podocytes in the kidney of diabetic rats.

The essential ingredient of Centella asiatic is asiatic acid (AA). There are a lot of biological activities in AA, such as anti-oxidant, anti-diabetic. However, so far, there have been no reports on the underlying protective mechanism of AA on podocytes. In this research, we observed the morphological changes of podocytes in diabetic rats by optics microscope and transmission electron microscopy and the protective effect of AA. Additionally, we investigated the expressions of nephrin, desmin and p-JNK, JNK in podocytes of diabetic rats and the influence of AA on podocytes and JNK signaling pathway. The results showed that AA could reduce renal function and urinary albumin. It could attenuate abnormal pathological findings of podocytes in kidney tissue of diabetic rats. Besides, treatment with AA could significantly improve the expression of nephrin and decrease expression of desmin. The ratio of p-JNK protein to JNK protein in podocytes was reduced considerably by AA. With the treatment dose of AA increased, the renal protective effect of AA was gradually improved. These results indicate that asiatic acid has a significant protective effect on diabetic nephropathy. Potential mechanisms include inhibiting the production of oxidants effectively, protection of podocytes, and suppression of the JNK signaling pathway activation. Therefore, there is an excellent prospect of using AA to treat diabetic nephropathy.