[Astragalus and angelica mixture inhibits the renal tubular epithelial cell injury induced by aristolochic-acid I].

OBJECTIVE: To investigate whether Chinese herb astragalus and angelica mixture (A&A) have influence on the renal tubular epithelial cell injury induced by aristolochic-acid I. METHODS: Human proximal tubular epithelial cell line HK-2 was pre-treated with AA-I (2.5 mg/L) for 4 hours. Cells were then treated with or without A&A for additional 44 hours. Cell apoptosis was evaluated by using FACS. Secreted fibronectin (FN) and TGF-beta1 levels were assayed by ELISA. The changes of AA-I-induced FN, TGF-beta1 level and the rate of apoptosis were compared before and after A&A treatment. RESULTS: There was basement secretion of TGF-beta1 by HK-2 cells (7.05+/-1.98 microg/L). Both normal serum (N-S) and A&A could not induce the cells to secret TGF-beta1(6.35+/-1.99 microg/L and 6.57+/-2.19 microg/L, vs. control, P>0.05). AA-I could induce the TGF-beta1 secretion by HK-2 cells (18.26+/-5.98 microg/L, vs. control, P<0.05). A&A could block AA-I-induced TGF-beta1 secretion by 63.5% (6.66+/-0.70 microg/L, vs. AA-I, P<0.05). It also suppressed AA-I-induced cell apoptosis by 93.7% (3.32%+/-0.41% vs. 19.19%+/-6.32% respectively, P<0.001) and FN secretion by 44% (1.64+/-1.11 folds vs. 2.93+/-0.87 folds respectively, P<0.05). CONCLUSION: A&A inhibits AA-I induced injury in human renal proximal tubule epithelial cells, whose mechanism may be partially through blocking TGF-beta1 secretion.