122 - Bioactive Peptides for Enhancing Intestine Health

Intestinal disorders and colitis affect both animals and humans. The pathogenesis behind the inflammation is complex and not entirely understood. Furthermore, the significant rise in antibiotic-resistant bacteria has emphasized an urgent need for alternative anti-infective therapies. Antimicrobial peptides (AMPs) is one of the appealing alternative to antibiotics due to their antimicrobial activity, mode of actions, and potential role in tissue repair. Epidermal growth factor (EGF) plays an important role in intestinal proliferation and differentiation and thus promotes intestinal development. Using food grade microorganisms such as Lactococcus lactis and yeast as hosts, our laboratory has produced recombinant porcine protegrin-1 (PG-1), a pig originated antimicrobial peptide and EGF via fermentation. Oral administration of PG-1 reduced Citrobacter rodentium induced intestinal infection in mice. This was evidenced by reduced histopathological changes in the colon, prevention of body weight loss, milder clinical signs of disease, and ultimately more effective clearance of bacterial infection. On the other hand, animal trials using the recombinant EGF demonstrated that it enhances intestinal development and growth of early weaned pig fed with antibiotic-free diet. Moreover, piglets challenged with enterotoxigenic Escherchia coli (E. coli) K88 showed similar beneficial responses to EGF as those fed diets with antibiotic in terms of improving gain to feed ratio and lowering oxidative stress. Taken together, our findings suggest the potential for cost-effective production and application of recombinant bioactive proteins as alternatives to antibiotics in animal health and production.