Ability of Lactobacillus plantarum lipoteichoic acid to inhibit Vibrio anguillarum-induced inflammation and apoptosis in silvery pomfret (Pampus argenteus) intestinal epithelial cells

• Lactobacillus plantarum LTA inhibits Vibrio anguillarum adhesion to FIECs.
• L. plantarum LTA inhibits V. anguillarum-induced NF-κB, IκB, Bcl2, BAX, IL-8 and TNF-α expression.
• L. plantarum LTA prevents V. anguillarum-induced activation of caspase-9 and caspase-3.
• L. plantarum LTA has potential as a new therapeutic agent against V. anguillarum-caused vibriosis in fish.

Lipoteichoic acid (LTA) is a major constituent of the cell wall of Gram-positive bacteria. The structure and immunomodulation of LTA vary greatly between different species. LTA from Lactobacillus plantarum has been shown to exert anti-pathogenic effects. Vibrio anguillarum is a major causative agent of vibriosis, one of the most prevalent fish diseases. The purpose of this study was to examine the effects of L. plantarum LTA on V. anguillarum growth, adhesion, and induced inflammation and apoptosis in intestinal epithelial cells of silvery pomfret (Pampus argenteus). Our results showed that L. plantarum LTA was unable to inhibit V. anguillarum growth; however, it significantly inhibited adhesion of V. anguillarum. It also showed significant inhibitory effects on EHEC-induced inflammation and apoptosis by modulating the expression of NF-κB (nuclear factor kappa B), IκB (inhibitor of NF-κB), Bcl2 (B-cell leukemia/lymphoma-2), BAX (Bcl-2-associated X protein), IL-8 (interleukin 8) and TNF-α (tumor necrosis factor-α), and via inhibition of caspase-9 and caspase-3 activation. These data extend our understanding of the beneficial effects of L. plantarum LTA, which is related to the inhibition of V. anguillarum, and suggest that L. plantarum LTA has potential as a new therapeutic agent against V. anguillarum-caused vibriosis in fish.