Abstract: Objective To investigate the protective effect of ginkgo biloba extract (EGb761) on acute renal injury induced by ischemia reperfusion (IR) in diabetic (DM) rats and its mechanism. Methods All rats were divided into five groups: control group(NC),DM group, DM-IR group, EGb761-100 group and EGb761-200 group(n=10). Rats in the EGb761-100 and EGb761-200 groups were received EGb761 by gavage for 14 days before IR model were prepared(100 mg/kg/d and 200 mg/kg/d,respectively). The levels of serum creatinine, cystatin C and urinary KIM-1 were measured, Pathological changes of renal tissue were observed under light microscope; Expression of inflammatory mediators（TGF-β1, TNF-α and IL-6）and oxidative stress index (superoxide dismutase and malondialdehyde ) in renal homogenate were measured; The expressions of Bax and Bcl-2 in renal tissue were measured by immunohistochemistry; The levels of Klotho in serum, urine and renal tissue and the expression of Klotho mRNA in renal tissue were detected. Results Compared with DM-IR group, EGb761 decreased levels of Scr, Cys-C, urinary KIM-1 and tubular Paller score（P<0.05）; EGb761 decreased the production of inflammatory mediators and attenuated the oxidative stress in IR injury rats（P<0.05）; EGb761 also decreased Bax and increased Bcl-2 in renal tissue（P<0.05）, and alleviated the reduced expression of Klotho in serum, urine and kidney tissue. Renoprotective effects in EGb761-200 group were more significant than that in EGb761-100 group. Conclusions EGb761 may alleviate renal function damage induced by IR in DM rats by inhibiting inflammatory response, reducing oxidative stress, anti-apoptosis and increasing Klotho.

Key words: Ginkgo biloba Extract, Diabetes Mellitus, Ischemia/reperfusion injury, renoprotective effects, Klotho