Polypeptides Isolated from <i>Lactococcus lactis</i> Alleviates Lipopolysaccharide (LPS)-Induced Inflammation in <i>Ctenopharyngodon idella</i>

Abstract

The main purpose of the present study was to evaluate the anti-inflammatory activity of Lactococcus lactis BL52 and isolate active substances responsible for anti-inflammatory activity. Head-kidney (HK) macrophages were used for in vitro bioassay-guided isolation, and the structure of the two peptides was identified by mass spectrometry analysis. Lipopolysaccharide (LPS)-induced inflammatory responses in Ctenopharyngodon idella were also examined to evaluate the in vivo anti-inflammatory activity of active substances. Two active peptides were isolated by HPLC from L. lactis BL52, and an in vitro anti-inflammatory assay demonstrated that peptide ALBL1 and ALBL2 dose-dependently inhibited LPS-induced inflammatory cytokines TNF-α, IL-6, and IL-1β and inflammatory factors NO and PGE 2 production in macrophages (p p C. idella treated with peptide ALBL1 and ALBL2 can relieve pathological inflammatory responses caused by LPS. These results suggest that the anti-inflammatory properties of peptide ALBL1 and ALBL2 might be a result from the inhibition of IL-6, IL-1β, and TNF-α expressions through the downregulation of Toll2/NF-κB signaling pathways.

Keywords

• polypeptide
• <i>Lactococcus lactis</i>
• <i>Ctenopharyngodon idella</i>
• lipopolysaccharide
• bioassay-guided isolation
• anti-inflammatory