BOARD-INVITED REVIEW: Peptide absorption and utilization: Implications for animal nutrition and health

Abstract

Over the last 50 yr, the study of intestinal peptide transport has rapidly evolved into a field with exciting nutritional and biomedical applications. In this review, we describe from a historical and current perspective intestinal peptide transport, the importance of peptides to whole-body nutrition, and the cloning and characterization of the intestinal peptide transporter, PepT1. We focus on the nutritional significance of peptide transport and relate these findings to livestock and poultry. Amino acids are transported into the enterocyte as free AA by a variety of AA transporters that vary in substrate specificity or as di- and tripeptides by the peptide transporter, PepT1. Expression of PepT1 is largely restricted to the small intestine in most species; however, in ruminants, peptide transport and activity is observed in the rumen and omasum. The extent to which peptides are absorbed and utilized is still unclear. In ruminants, peptides make a contribution to the portal-drained visceral flux of total AA and are detected in circulating plasma. Peptides can be utilized by the mammary gland for milk protein synthesis and by a variety of other tissues. We discuss the factors known to regulate expression of PepT1 including development, diet, hormones, diurnal rhythm, and disease. Expression of PepT1 is detected during embryological stages in both birds and mammals and increases with age, a strategic event that allows for the immediate uptake of nutrients after hatch or birth. Both increasing levels of protein in the diet and dietary protein deficiencies are found to upregulate the peptide transporter. We also include in this review a discussion of the use of dietary peptides and potential alternate routes of nutrient delivery to the cell. Our goal is to impart to the reader the nutritional implications of peptide transport and dietary peptides and share discoveries that shed light on various biological processes, including rapid establishment of intestinal function in early neonates and maintenance of intestinal function during fasting, starvation, and disease states.

Effect of soybean meal fermented with Bacillus subtilis BS12 on growth performance and small intestinal immune status of piglets

“…TCA-SP consists of small peptides with 2-20 residues. Di-and tripeptides in TCA-SP can be directly absorbed by the animal gut, and AA in the form of small peptides is transported more quickly than constituent AAs in free form (Gilbert, Wong, & Webb, 2008). In Bi et al (2015) research, the soybean peptides were increased 50% after 48 h fermentation by B. subtilis XZI125 had high protease activity.…”

Effects of Collagen-Derived Oligopeptide Prolylhydroxyproline on Differentiation of Mouse 3T3-L1 Preadipocytes

“…Oligopeptides such as Pro-Hyp can be transported into a cell via the solute carrier family known as proton-coupled oligopeptide transporters, namely, PEPT1, PEPT2, PHT1 and Ci1 (PHT2 in human) (Gilbert et al, 2008). Therefore, we examined the expression of these transporter genes in 3T3-L1 cells.…”

Action of a pancreatin and an Aspergillus oryzae protease on whey proteins: correlation among the methods of analysis of the enzymatic hydrolysates

“…During protein metabolism, the first stage of hydrolysis leads to the formation of free amino acids (AA) and small peptides (2-6 AA residues), which can be further hydrolyzed by brush border peptidases to produce AA and di-and tripeptides (Hinsberger and Sandhu 2004). The amino acids can be absorbed either in the free form, by simple and facilitated diffusion (membrane transporters), or in the di-and tripeptide form (oligopeptide transporters) (Gilbert et al 2008). Furthermore, according to Frenhani and Burini (1999), the di-and tripeptides are more efficiently absorbed than is an equivalent mixture of free amino acids.…”