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Despite cisplatin has been widely used in the treatment of various cancers, the noteworthy nephrotoxicity greatly constrained its clinical value. For this reason, finding novel targeted therapies to attenuate the nephrotoxicity of cisplatin should be pretty significant. Our previous study found that histone deacetylase sirtuin 6 (SIRT6) could be an ideal target for the treatment of cisplatin-induced acute kidney injury. In this study, we explored the protective effects of ellagic acid, a natural polyphenol compound that activates SIRT6, on cisplatin-induced nephrotoxicity. Pre-treatment of ellagic acid attenuated cytotoxicity of cisplatin in primary renal cells and TCMK-1 cells. Moreover, ellagic acid ameliorated renal dysfunction, apoptosis and fibrosis induced by cisplatin in mice. Furthermore, ellagic acid reduced nephrotoxicity-associated inflammatory factor interleukin (IL)-1β and IL-6 expression both in vitro and in vivo. Mechanistically, ellagic acid reversed cisplatin-reduced SIRT6 expression and diminished cisplatin-induced tumor necrosis factor (TNF)-α expression. And SIRT6 knockdown abrogated the protective effects of ellagic acid on cisplatin-induced cell apoptosis, indicating the renal-protective effects of ellagic acid are mainly dependent on ellagic acid-mediated SIRT6 activation. Our results provide preclinical rationale for using ellagic acid as a feasible and promising agent to ameliorate cisplatin-induced acute kidney injury, and support ellagic acid as a potential adjunctive therapy for future cancer treatment.

Nonalcoholic fatty liver disease (NAFLD) is a high-incidence lipid disorder that affects more than a quarter of the population worldwide, and dietary intervention is the recognized treatment. Starch is the main component of staple foods that are consumed daily, and the effects, metabolic pathway, and molecular mechanism of starch in the context of NAFLD remain unclear. Our study showed that a high-starch carbohydrate diet (HCD) led to the occurrence and exacerbation of NAFLD in mice. Transcriptomics and metabonomic analyses showed that the increased fatty acid influx mediated by NADPH oxidase 2 (NOX2) exacerbated NAFLD. Knocking down NOX2 specifically alleviated HCD-induced NAFLD in vivo and in vitro. Moreover, the large amounts of ROS produced by NOX2 further exacerbated insulin resistance and increased lipolysis in perirenal white adipose tissue (periWAT), thereby providing fatty acids for hepatic lipid synthesis. In addition, the interaction between AMPKα1 and p47phox was the pathway that mediated the high expression of NOX2 induced by a HCD. Our study systematically demonstrated the effect of a HCD on NAFLD. Elevated fatty acid influx is a unique molecular regulatory pathway that mediates HCD-induced NAFLD exacerbation, which is different from the effect of simple sugars. Additionally, NOX2 was suggested to be a specific and effective drug target for NAFLD.