Abstract:【Abstract】Objective To study the protective effect of oridonin (Ori) on diabetic nephropathy (DN) rats.Methods Rats were randomly divided into Control group, DN model group, DN+Ori (5 mg/kg), DN+Ori(10 mg/kg) and DN+Ori (20 mg/kg) group. The diabetic rat model was established by highfat diet combined with chemical induction. 24 hours urine was collected to detect urinary protein content, blood was taken to detect serum creatinine (SCr) and urea nitrogen (UN). Hematoxylineosin (HE) and TUNEL staining were used to observe renal pathology. Western blot was used to detect the expression of apoptosisrelated proteins Caspase3, Caspase9, B cell lymphoma factor2 (Bcl2), Bcl2related X protein (Bax) and inflammatory pathway NFkappa B p65, MIP2. ELISA was used to detect the expression of IL1beta, IL6 and TNFalpha in serum. Results Comparing with the control group, Ori could reduce the content of urinary protein, serum creatinine and urea nitrogen in DN model mouse (P<005), improve the pathological damage of kidney tissue and reduce the apoptotic rate (P<005), downregulate the expression of Caspase3, Caspase9 and Bcl2, upregulate the expression of Bax (P<005), inhibit the expression of inflammatory factors IL6 and TNFalpha, increase IL4 and IL10 (P<005). At the same time, Ori could inhibit the protein expression of NFkappa B 65 and MIP2 (P<005). Conclusion Ori can alleviate renal injury and immune disorder in diabetic nephropathy rats by inhibiting the activation of NFkappa B p65.