LncRNA CA12-AS1 targets miR-133a to promote LPS-induced inflammatory response in bovine mammary epithelial cells

Bovine mastitis seriously affects milk production and quality and causes huge economic losses in the dairy industry. Recent studies have shown that long non-coding RNAs (lncRNAs) may regulate bovine mastitis. In this study, the expression of lncRNA CA12-AS1 was significantly upregulated in LPS-induced bovine mammary epithelial cells (bMECs) but negatively correlated with the expression of miR-133a, suggesting that it may be related to the inflammatory response in bMECs. Dual luciferase reporter gene assay revealed that miR-133a is a downstream target gene of lncRNA CA12-AS1. Furthermore, lncRNA CA12-AS1 silencing negatively regulated the expression of miR-133a inhibited the secretion of inflammatory factors (IL-6, IL-8 and IL-1β) and decreased the mRNA expression levels of nuclear factor kappa B (NF-κB) (p65/p50) and apoptosis-related genes (BAX, caspase3 and caspase9). LncRNA CA12-AS1 silencing also promoted the mRNA expression levels of the Tight junction (TJ) signaling pathway-related genes (Claudin-1, Occludin and ZO-1), apoptotic gene BCL2, proliferation-related genes (CDK2, CDK4 and PCNA) and the viability of bMECs. However, overexpression of lncRNA CA12-AS1 reversed the above effects. These results revealed that lncRNA CA12-AS1 is a pro-inflammatory regulator, and its silencing can alleviate bovine mastitis by targeting miR-133a, providing a novel strategy for molecular therapy of cow mastitis.