OBJECTIVETo examine the protective effects of Astragalus injection (AI) on cisplatin (DDP)-induced nephrotoxicity and to explore the mechanism of its nephroprotection.

METHODThe S180-bearing model was established, and fifty mice were randomly divided into five groups: control mice, DDP-injected mice (3.5 mg x kg(-1)) and AI-pretreated mice (12, 8, 4 g x kg(-1)). Tumor inhibition rate, renal functions, histological findings were investigated. The apoptotic cells were counted by TUNEL and the presence of Bax, Bcl-2 in renal tissues was determined by immunohistochemistry.

RESULTSAdministration of DDP or DDP plus AI showed promising anti-tumor activities as compared with control group. Interestingly, a combination of DDP and AI (12, 8 g x kg(-1)) led to enhanced tumor growth inhibition as compared with DDP alone (all P < 0.05). Compared with that from control, the number of TUNEL-positive cells and the Bax/Bcl-2 ratio was increased significantly in the kidneys of DDP treated mice (P < 0.05). High-dose AI pretreatment significantly reduced the elevated number of TUNEL-positive cells and the Bax/Bcl-2 ratio (P < 0.05), and it showed a superior nephroprotective effect than any other dose. AI significantly also decreased both the damage to renal function and histological pathology.

CONCLUSIONPre-treatment with AI attenuates cisplatin-induced nephrotoxicity without compromising the anti-tumor efficacy of DDP, which might be involved in regulating the Bax and Bcl-2 expression.