Lysozyme improves gut performance and protects against enterotoxigenic Escherichia coli infection in neonatal piglets

Abstract

Diarrhea remains one of the leading causes of morbidity and mortality globally, with enterotoxigenic Escherichia coli (ETEC) constituting a major causative pathogen. The development of alternative treatments for diarrhea that do not involve chemotherapeutic drugs or result in antibiotic resistance is critical. Considering that lysozyme is a naturally occurring antimicrobial peptide, in a previous study we developed a transgenic pig line that expresses recombinant human lysozyme (hLZ) in its milk. In the present study, we examined the protective effects of the consumption of this milk against ETEC infection in neonatal piglets. We found that consuming hLZ milk facilitated faster recovery from infection and decreased mortality and morbidity following an ETEC oral inoculation or infection acquired by contact-exposure. The protective effect of hLZ was associated with the enrichment of intestinal bacteria that improve gut health, such as Lactobacillus, and the enhancement of the mucosal IgA response to the ETEC-induced diarrhea. Our study revealed potential protective mechanisms underlying the antimicrobial activity of human lysozyme, validating the use of lysozyme as an effective preventive measure for diarrhea.

Dietary lysozyme supplement alters serum biochemical makers and milk metabolite profile of sows via gut microbiota

“…Genera that exerted a significant effect on both serum immune indices and milk metabolites were filtered, and a possible regulation network is shown in Figure 6B. Based previous reports, Lactobacillus and Prevotella may play a key role in lysozyme mediated host-microbial interactions [3, 46, 50].…”

“…This study also identified that Lactobacillus amylovorus is significantly increased in the 0.5 kg/t group (Figure 1F). Lactobacillus is reported to improve the intestinal environment and activate intestinal mucosal immunity in many species, resulting in enhanced SIgA production of the innate immune system, which is essential for the prevention of fimbriae-mediated colonization and the maintenance of intestinal barrier function [3, 50].…”

“…Enteric infections caused by pathogens, like Enterotoxigenic Escherichia coli (ETEC), have a significant negative effect on neonatal survival and animal health in swine production [1, 2, 3]. Animal infants infected by pathogenic bacteria often suffer from persistent diarrhea and serious inflammation [3, 4].…”

“…Enteric infections caused by pathogens, like Enterotoxigenic Escherichia coli (ETEC), have a significant negative effect on neonatal survival and animal health in swine production [1, 2, 3]. Animal infants infected by pathogenic bacteria often suffer from persistent diarrhea and serious inflammation [3, 4]. Prolonged inflammation of the intestinal tract leads to substantial destruction of the intestinal epithelia, resulting in malnutrition and impairing the early growth of infants [5, 6, 7].…”

“…Lysozyme could be effective against a wide range of gastrointestinal pathogens, such as Listeria monocytogenes , Clostridium perfringens , Candida spp., and Helicobacter pylori in vitro [7, 21]. Bacterial sensitivity to lysozyme is due to the activation of innate components of the immune system, such as increased neutrophil activation during inflammation [3, 22]. It has been reported that lysozyme may possess an anti-inflammatory effect via inhibiting JNK phosphorylation [23].…”