In periparturient dairy cows, high non-esterified fatty acids (NEFAs) caused by a severe negative energy balance induce oxidative stress and metabolic dysfunction, which pose a severe challenge to the dairy industry. Resveratrol (RES) is a polyphenolic compound with antioxidant, anti-inflammatory and multiple other physiological effects. However, its effect on oxidative damage triggered by NEFAs in bovine mammary epithelial cells is rarely reported. This study aimed to investigate the antioxidant effects and underlying molecular mechanisms of RES in NEFA-challenged BMECs. The results showed that RES ameliorated NEFA-induced oxidative damage by upregulating antioxidant enzyme expression and reducing malondialdehyde (MDA) and reactive oxygen species (ROS). Furthermore, exogenous NEFAs resulted in a decrease in mitochondrial membrane potential (MMP), cellular adenosine triphosphate (ATP) production, energy metabolism (NAD⁺/NADH ratio), abnormal mitochondrial structure and an increase in apoptosis levels. RES treatment restored mitochondrial function in NEFA-stressed BMECs, as evidenced by the increase in MMP, ATP generation and NAD⁺/NADH ratio accompanying the decline in mitochondrial structural abnormalities and cell apoptosis. In addition, in vivo studies in a mouse model of oxidative damage induced by high-fat diet (HFD) demonstrated that RES alleviated oxidative damage (decreased MDA content) and mitochondrial dysfunction (decreased expression of Drp1 and Fis1 and increased levels of Mfn2, Cyt C mRNA and ATP production) in mammary gland tissue. Overall, these findings suggested that RES could alleviate NEFA-induced oxidative damage in BMECs by modulating mitochondrial function, thereby contributing to the prevention and treatment of oxidative damage in perinatal dairy cows with a negative energy balance.

Heat stress in dairy cows is aggravated by Global warming, which negatively affects their performance and health, especially high yielding cows are more susceptible to high temperature and humidity in summer. Besides increasing body temperature and reducing feed intake, heat stress also compromises mammary gland function by inducing apoptosis in bovine mammary epithelial cells (BMECs). UFBP1 (Ufm1-binding protein 1) serves as an essential component of ufmylation, is crucial for the preservation of cellular homeostasis. However, little is known about its contribution to heat stress-induced apoptosis in BMECs. Therefore, the present study aimed to elucidate the effect of UFBP1 on heat stress-induced apoptosis through knockdown and overexpression of UFBP1 in BMECs. The results showed that heat stress triggered cell apoptosis (increased apoptosis rate and Bax/Bcl-2 protein expression) and decreased the expression of genes associated with the production of milk fat and protein both in vivo and in vitro studies. Furthermore, UFBP1 silencing aggravated the high-temperature-induced cell damage, and overexpression of UFBP1 attenuated heat stress-induced mitochondrial dysfunction, as evidenced by increased mitochondrial membrane potential (MMP), ATP synthesis and NAD⁺/NADH ratio, as well as the reduced reactive oxygen species (ROS) generation. Importantly, the mitochondrial apoptosis pathway triggered by heat stress was blocked by UFBP1, as indicated by the reduced apoptosis rate and Bax/Bcl-2 protein expression. In addition, UFBP1 restored the expression of milk fat and protein-related genes in heat-stressed BMECs. In conclusion, these findings indicate that UFBP1 may serve as a promising therapeutic target for ameliorating heat stress in dairy cows, thereby providing novel theoretical insights into the mitigation of adverse thermal stress effects on livestock productivity.

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.

Spermine (Spe) plays a critical role in maintaining the integrity of the intestinal barrier and promoting intestinal development. However, the therapeutic role of Spe on ulcerative colitis (UC) remains unclear. This study aims to research the impact and mechanism of Spe on dextran sulfate sodium (DSS)-induced colitis in mice. Twenty-eight C57BL/6 mice were orally administered Spe before and during DSS treatment to evaluate its protective effects. Lipopolysaccharides (LPSs) were used to construct an in vitro UC model in IEC-6 cells. The study indicates that Spe treatment upregulated the expression of tight junction protein occludin and inhibited NLRP3 mediated inflammatory response by downregulating the levels of NLRP3, Caspase-1, IL-1β, IL-18 and TNF-α in the colon of DSS-treated mice. In addition, Spe enhanced mitophagy in colitis mice by increasing expressions of mitophagy factors (PINK1, Parkin, LC3-II) in DSS-treated mice. PINK1-mediated mitophagy helps alleviate LPS-induced mitochondrial damage in IEC-6 cells. Furthermore, Spe regulates the gut microbiota composition in mice with colitis by increasing the abundance of unclassified Muribaculaceae, reducing the levels of Firmicutes and Blautia, and lowering the Firmicutes/Bacteroidetes ratio. In conclusion, spermine exhibited treatment efficacy on DSS-induced colitis by inhibiting NLRP3-mediated inflammatory response, promoting mitophagy and improving intestinal microbial dysbiosis.

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.