Objective: Negative energy balance in transition cows elevates the circulating concentrations of non-esterified fatty acids (NEFA), potentially leading to mastitis and posing a significant threat to the dairy industry. Resveratrol is a polyphenolic compound with anti-inflammatory properties, yet its role in NEFA-induced inflammation in bovine mammary epithelial cells (BMECs) remains unclear. This study aimed how resveratrol protects against mastitis and its underlying mechanisms.Methods: BMECs were pre-treated with 100 μM resveratrol for 24 h, and then treated with 0.9 mM NEFAs for 4 h, and a PINK1 inhibitor was used to assess the mechanisms involved. Furthermore, a mouse model of mastitis was utilized to evaluate the hepatoprotective effects of resveratrol against mastitis in vivo.Results: Resveratrol significantly attenuated the NEFA-induced inflammatory response, evidenced by reduced levels of NLRP3 inflammasome components (NLRP3, caspase1, IL-1β) and pro-inflammatory cytokines (IL-6, IL-1β and TNF-α). Mechanistically, resveratrol promoted mitophagy by upregulating levels of LC3-II, PINK1, and Parkin, while downregulating P62 expression. The anti-inflammatory effect of resveratrol was reversed when PINK1 was inhibited. In vivo experiments confirmed that resveratrol alleviated mammary gland inflammation and enhanced PINK1-mediated mitophagy.Conclusion: This study demonstrates that resveratrol mitigates NLRP3-mediated inflammation by activating PINK1-mediated mitophagy, suggesting its potential as a therapeutic option for mastitis in perinatal dairy cows with negative energy balance.

Resveratrol (RES) has been shown to exhibit therapeutic efficacy against fatty liver disease. Yet, the molecular mechanisms by which RES ameliorates liver injury remain unclear. The aim of this study was to investigate the therapeutic effect and mechanism of resveratrol in fatty liver disease. It was found that dairy cows with fatty liver exhibit characteristic hepatic pathologies, including ballooning degeneration, lipid accumulation and elevated serum AST and ALT levels. Parallel to these changes, we observed significant upregulation of the NLRP3 inflammasome alongside suppression of mitophagy in the liver. Additionally, it was demonstrated in vitro that resveratrol pretreatment effectively alleviated PA-triggered NLRP3 inflammasome activation and mitochondrial dysfunction. Furthermore, RES’s mitigating effects against NLRP3 inflammation and mitochondrial injury were reversed by suppressing PINK1-medicated mitophagy. In vivo experiments further demonstrated that resveratrol administration attenuated HFD-induced liver injury and lipid accumulation in a mouse model, concurrent with suppressed NLRP3 activation and an increase in mitophagy, further confirming the mechanism identified in vitro. Our findings reveal that RES ameliorates fatty liver injury primarily by inhibiting the NLRP3 inflammasome through PINK1-mediated mitophagy, which provides a potential novel therapeutic strategy for mitigating fatty liver disease.