The abrupt pathological deterioration of cisplatin‐induced acute kidney injury: Emerging of a critical time point

Cisplatin (CP), an anticancer drug, often causes kidney damage. However, the mechanism of CP‐induced acute kidney injury (AKI) is not completely understood. AKI was induced by intravenous injection (i.v.) of cisplatin at doses of 5, 8, and 10 mg/kg. Anemoside B4 (B4) (20 mg/kg, i.m.) and dexamethasone (DXM) (0.5 mg/kg, i.v.) were used for AKI treatment. Biochemical indicators were assessed using an automatic biochemical analyzer, protein expression was analyzed by western blotting, and morphological changes in the kidney were examined by PAS staining. The serum creatinine (Cre) and blood urea nitrogen (BUN) levels did not change significantly in the first 2 days but abruptly increased on the third day after CP injection. The serum albumin (ALB) and total protein (TP) levels decreased in both a time‐ and dose‐dependent manner. The urine protein level increased, the clearing rate of Cre decreased distinctly, and morphologic changes appeared in a dose‐dependent manner. The protein expression of p53/caspase‐3, NLRP3, IL‐6, and TNF‐α was obviously upregulated on day 3; concurrently, nephrin and podocin were downregulated. The expression of LC3II and p62 was upregulated significantly as the CP dose increased. B4 and DXM obviously decreased the BUN and Cre levels after 3 or 5 days of treatment. AKI appeared distinctly in a time‐dependent manner at 2 to 5 days after the administration of 5 mg/kg CP and in a dose‐dependent manner upon the administration of 5, 8, and 10 mg/kg CP. The third day was a significant time point for renal deterioration, and treatment with B4 and DXM within the first 3 days provided significant protection against AKI.