Cytochalasin B Alleviates LPS-Induced Mastitis and Modulates the Expression of PI3K/N-WASP/ARP2/3-Related Molecules

Cytochalasin B (CB) inhibits actin polymerization and modulates cytoskeletal dynamics, but its role in mastitis remains unclear. This study investigated the protective effects of CB against mastitis and its association with PI3K/N-WASP/ARP2/3-related molecular alterations. Transcriptomic analysis of mammary tissues from healthy cows and cows with subclinical or clinical mastitis revealed extensive transcriptional remodeling during mastitis progression. Validation showed enhanced inflammatory responses accompanied by increased expression of PI3K, N-WASP, CLTC, ARP2, and ARP3 in mastitic tissues. In LPS-stimulated bovine mammary epithelial cells (MAC-T), CB reduced pro-inflammatory cytokine expression, increased IL-10 expression, and attenuated the abnormal elevation of PI3K/N-WASP/ARP2/3-related molecules. Consistently, in an LPS-induced mouse mastitis model, CB alleviated mammary tissue injury and inflammatory cell infiltration, improved inflammatory cytokine profiles, and reduced the expression of PI3K, N-WASP, CLTC, ARP2, and ARP3. Collectively, CB attenuates LPS-induced mammary inflammation and tissue injury, and these effects are associated with alterations in PI3K/N-WASP/ARP2/3-related cytoskeletal molecules. These findings provide new evidence linking cytoskeleton-related molecular alterations to mastitis inflammation and the anti-inflammatory effects of CB.