Protection of bovine mammary epithelial cells against lipopolysaccharide-induced inflammatory responses using Centella asiatica through its antioxidant and anti-inflammatory activities

: Bovine mastitis, an inflammatory condition affecting dairy cow udders, results in decreased milk quantity and quality, posing significant economic losses in the dairy industry. With increasing interest in natural products, Centella asiatica has garnered attention for its potent anti-inflammatory and antioxidant properties. Objective: This study aimed to investigate the potential protective effects of C. asiatica extracts (CE) against lipopolysaccharide (LPS)-induced inflammation in bovine mammary epithelial cells (MAC-T). : CEs were prepared by extracting C. asiatica leaf powder using ethanol at concentrations of 60%, 70%, 80%, 90%, and 100%. In LPS-stimulated MAC-T cells, the study investigated the ability of CE to reduce oxidative stress and inflammation and its impact on casein protein synthesis. : C. asiatica extract with 60% ethanol (CE60) exhibited the highest radical scavenging activity and total phenolic content among the tested extracts. In MAC-T cells, CE60 significantly attenuated LPS-induced inflammation by down-regulating pro-inflammatory cytokines such as cyclooxygenase-2, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6, as well as inhibiting nuclear factor kappa B activation. CE60 also reduced intracellular reactive oxygen species through upregulating nuclear factor erythroid-2-related factor 2 and associated antioxidant enzymes, including glutathione peroxidase (GPx) 1, GPx4, superoxide dismutase (SOD) 1, SOD2, and catalase. Moreover, CE60 restored the synthesis of casein proteins (CSN1S1, CSN1S2, and CSN2) in LPS-treated MAC-T cells, indicating a protective effect on lactation function under inflammatory conditions. : Taken together, CE60 has potential as a natural substance for the prevention of bovine mastitis by reducing oxidative stress and inflammation in mammary epithelial cells.