Myricetin-Loaded Nanomicelles Protect against Cisplatin-Induced Acute Kidney Injury by Inhibiting the DNA Damage-cGAS–STING Signaling Pathway

Acute kidney injury (AKI) is the most common side effect of the anti-cancer drug cisplatin, and currently, no effective preventive measures are available in clinical practice. Oxidative stress and DNA damage mechanisms may be involved in cisplatin-induced AKI. In this study, we prepared Kolliphor HS15-based myricetin-loaded (HS15-Myr) nanomicelles and explored the mechanism of protection against cisplatin-induced AKI. In vitro results showed that the HS15-Myr nanomicelles enhanced the antioxidant activity of myricetin (Myr) and inhibited cisplatin-induced proliferation inhibition of HK-2 cells. Moreover, the HS15-Myr nanomicelles inhibited cisplatin-induced reactive oxygen species accumulation, mitochondrial membrane potential reduction, and DNA damage, which might be related to the inhibition of the cyclic GMP–AMP synthase (cGAS)stimulating interferon gene (STING) signaling pathway. In vivo results in mice showed that the significant reductions in body weight and renal indices and the increased blood urea nitrogen and serum creatinine levels induced by cisplatin could be significantly reversed by pretreating with the HS15-Myr nanomicelles. Furthermore, nanomicelle pretreatment significantly altered the activities of antioxidant enzymes (e.g., GSH, MDA, and SOD) induced by cisplatin. In addition, cisplatin-induced inflammatory responses in mouse kidney tissue were found to be inhibited by pretreatment with HS15-Myr nanomicelles, such as IL-1β and TNF-α expression. The nanomicelles also significantly inhibited cisplatin-induced activation of the DNA damage-cGAS–STING pathway in kidney tissues. Together, our findings suggest that Myr-loaded nanomicelles are potential nephroprotective drugs.