Regulation of Intestinal Epithelial Cells Properties and Functions by Amino Acids

Abstract

Intestinal epithelial cells (IECs) line the surface of intestinal epithelium, where they play important roles in the digestion of food, absorption of nutrients, and protection of the human body from microbial infections, and others. Dysfunction of IECs can cause diseases. The development, maintenance, and functions of IECs are strongly influenced by external nutrition, such as amino acids. Amino acids play important roles in regulating the properties and functions of IECs. In this article, we briefly reviewed the current understanding of the roles of amino acids in the regulation of IECs' properties and functions in physiological state, including in IECs homeostasis (differentiation, proliferation, and renewal), in intestinal epithelial barrier structure and functions, and in immune responses. We also summarized some important findings on the effects of amino acids supplementation (e.g., glutamine and arginine) in restoring IECs' and intestine functions in some diseased states. These findings will further our understanding of the important roles of amino acids in the homeostasis of IECs and could potentially help identify novel targets and reagents for the therapeutic interventions of diseases associated with dysfunctional IECs.

l-Arginine alleviates heat stress-induced intestinal epithelial barrier damage by promoting expression of tight junction proteins via the AMPK pathway

“…1a, l-arginine concentrations exceeding 5 mmol suppressed cell proliferation and was even cytotoxic in the optimized culture environment. Heat stress increases the requirement of nutrition for cells to survive [29]. However, the protective effect was not lineally dependent on dose, and a high dose of l-arginine (10 mmol) decreased cell viability.…”

“…Luminal nutrients contribute to alterations in the morphology and functions of IECs and intestines [29]. l-Arginine stimulates cell proliferation [40], enhances the intestinal mucosal immune function [19], and improves intestinal recovery [26].…”

Ulcerative colitis: understanding its cellular pathology could provide insights into novel therapies

“…The intestinal epithelium is lined with a single layer of polarized cells, whose major cell types include colonocytes, enteroendocrine, goblet cells and stem cells epithelial cells eventually shed into the lumen at the apex of crypts [14]. Intestinal epithelial stem cells can specialize into many cell types including enterocytes, Paneth cells, goblet cells, and neuroendocrine cells [15]. Most of the cells present in the intestine are absorptive cells, with the exception of crypt cells that are principally secretory cells [2].…”

Insights into the Role of Human Gut Microbiota in Clostridioides difficile Infection

“…Butyric acid is a source of energy for the intestinal cells and plays a key role in the regulation of the proliferation, the intestinal epithelial cells' diversity, and in preserving the integrity of the gut epithelium [101]. It protects the host from infection by increasing the defense barriers through the stimulation of the production of mucin and antimicrobial peptides [102].…”