Proteomics analysis reveals the mechanism of anemoside B4 in treating clinical mastitis in dairy cows

(1) Background: The therapeutic efficacy of AB4 in cows with CM is well-established, but the specific mechanism remains to be explored. This study was based on Label free relative quantitative proteomics technology to reveal the internal mechanism of AB4 treatment of CM; (2) Methods: Twelve healthy Chinese Holstein cows (group C) and twelve Chinese Holstein cows (group T) with CM were selected. Administer 30 mL of AB4 via intramuscular injection to cows with CM once per day, for 7 consecutive days. The tail venous blood of group C on any day and group T before medication on day 1 (designated as T1) and after medication on day 7 (designated as T2) were collected. Randomly divide the samples from each of the three groups into three subgroups (three biological replicates, with each replicate consisting of an equal mixture of four plasma samples). They are labelled C1, C2, C3 and T1-1, T1-2, T1-3, T2-1, T2-2, T2-3. The differential proteins of AB4 in the treatment of CM were screened and bioinformatic analysis was performed; (3) Results: AB4 could regulate the levels of HSPs and other proteins, participate in chemokine signal transduction, leukocyte migration across endothelial cells, MAPKs pathway and other pathways to improve the inflammatory response of the body. In addition, the cured cows showed significantly higher complement lev-els, b-defensin 12 levels, and the ability to regulate lipid metabolism compared to diseased and healthy cows, suggesting that AB4 can directly activate C2, triggering downstream responses to activate the complement system, while stimulating defensins secretion and regulating lipid metabolism.