Quercetin modulates Chitinase-3-like protein 1 expression and inflammatory responses in lipopolysaccharide-stimulated buffalo granulosa cells

Ovarian inflammation can impair buffalo fertility by disrupting the granulosa cell function and oocyte development. Chitinase-3-like protein 1 (CHI3L1) is associated with inflammation in other species, whereas quercetin is a flavonoid known for its anti-inflammatory properties. This study aimed to evaluate CHI3L1 expression and effects of quercetin on lipopolysaccharide (LPS)-induced inflammation in buffalo granulosa cells. Buffalo granulosa cells were cultured in vitro and challenged with LPS to induce inflammation with or without quercetin co-treatment. CHI3L1 and pro-inflammatory cytokine levels (IL-1β, IL-6, and TNF-α) were quantified using real-time PCR and ELISA, and intracellular reactive oxygen species (ROS) were measured using a fluorescence assay. The effect on oocyte maturation was assessed by culturing cumulus-oocyte complexes under these conditions. LPS challenge significantly increased CHI3L1 expression, proinflammatory cytokine levels, and ROS production in granulosa cells. These inflammatory changes are associated with reduced oocyte maturation rate. Quercetin treatment markedly downregulated LPS-induced CHI3L1 and cytokine expression, attenuated ROS generation, and significantly improved oocyte maturation. These results indicate that CHI3L1 is a key mediator of LPS-induced ovarian inflammation, and that quercetin effectively mitigates these effects, thereby enhancing the oocyte maturation environment. These findings highlight the potential of quercetin as a therapeutic agent for mitigating ovarian inflammation and improving fertility in buffaloes.