Peptidoglycan derived from Lactobacillus rhamnosus MLGA up-regulates the expression of chicken β-defensin 9 without triggering an inflammatory response

Abstract

Defensins are critical components of the innate immune system and play an important role in the integration of innate and adaptive immune responses. Although information on the immunomodulatory properties of peptidoglycan from bacteria is abundant, little is known about the β-defensin induction effect of peptidoglycan from the probiotic Lactobacillus. This study investigated the effect of intact peptidoglycan from L. rhamnosus MLGA on the induction of avian β-defensin 9 in chicken immune cells and intestinal explants. Peptidoglycan from Lactobacillus rhamnosus MLGA dose dependently promoted avian β-defensin 9 mRNA expression in chicken PBMCs, splenocytes, thymocytes, hepatocytes, and chicken embryo jejunum, ileum, and cecum explants and increased the capacity of PBMC or splenocyte lysates to inhibit the growth of Salmonella Enteritidis. In contrast to the effect of L. rhamnosus MLGA-derived peptidoglycan, peptidoglycan derived from pathogenic Staphylococcus aureus reduced avian β-defensin 9 mRNA expression in chicken PBMCs and splenocytes. The inducible effect of peptidoglycan from L. rhamnosus MLGA on avian β-defensin 9 expression in PBMCs and splenocytes was observed without activation of the expression of associated pro-inflammatory cytokines IL-1β, IL-8, and IL-12p40, whereas these cytokine expressions were suppressed by peptidoglycan hydrolysate obtained by lysozyme digestion. The results of the present study show the capability of peptidoglycan derived from L. rhamnosus MLGA to induce the antimicrobial peptide defensin while simultaneously avoiding the deleterious risks of an inflammatory response.

Probiotic Lactobacilli Do Not Protect Chickens against Salmonella Enteritidis Infection by Competitive Exclusion in the Intestinal Tract but in Feed, Outside the Chicken Host

“…It has been repeatedly confirmed that lactobacilli produce metabolites that suppress the growth of Salmonella [28][29][30]. Lactobacilli also produce metabolites affecting host gene expression [31,32]. We have also reported that whenever lactobacilli overgrow, they efficiently suppress growth of other gut microbiota members [15].…”

Probiotic Escherichia coli Nissle 1917 protect chicks from damage caused by Salmonella enterica serovar Enteritidis colonization

“…However, it is well known that long-term and excessive use of antibiotics can lead to problems such as pathogen drug resistance and antibiotic residues ( Ye et al., 2007 ). Probiotics are promising antibiotic substitutes, that can inhibit the growth and reproduction of pathogenic bacteria ( Nakphaichit et al., 2019 ), regulate immunity ( Huang et al., 2020 ), enhance intestinal barrier function, and promote the balance of intestinal microbiota ( Zhang et al., 2021 ). Screening for probiotics that can inhibit S. Enteritidis is expected to eliminate the disadvantages of antibiotics.…”

Host Defense Peptides in Nutrition and Diseases: A Contributor of Immunology Modulation

“…reuteri I5007 could enhance the HDPs via increasing colonic butyric acid production and activating peroxisome proliferator-activated receptor γ (PPAR-γ) and G-protein-coupled receptor 41 (GPR41) or downstream molecules but not intestinal microbiota structure changes Lactobacillus rhamnosus MLGA dose-dependently promoted avian β-defensin 9 mRNA expression in chicken PBMCs and splenocytes without activation of the expression of pro-inflammatory cytokines interleukin (IL)-1b, IL-8, and IL-12 Lactobacillus plantarum ZLP001 induced porcine HDP expression in vivo and in vitro , providing a promising approach to improve intestinal health and enhance diarrhea resistance in weaning piglets …”