Functions and Signaling Pathways of Amino Acids in Intestinal Inflammation

Figure 1

Possible signaling mechanisms of amino acids in intestinal inflammation in the ECs are illustrated. Amino acids ameliorate intestinal inflammation by impressing NF-κB and MAPK pathway. Amino acids activate Nrf2 pathway to regulate intestinal inflammation via inhibiting oxidative stress and the expressions of proinflammatory cytokines. Amino acids activate iNOS to inhibit NF-κB pathway by the production of NO. ACE2 combines B0AT1 to regulate uptake of Trp in IECs, which activates expressions of antimicrobial peptides to regulate intestinal microbiota. ACE2 illuminate intestinal inflammation by regulating innate immune responses and intestinal microbiota is not shown in the figure. GCN2 regulates intestinal inflammation by inhibiting inflammasome activation, triggering autophagy, and preventing oxidative stress. CaSR activated by Trp exerts anti-inflammation roles via activating the complex of Β-arrestin 2 (β-arr2) to inhibit NF-κB and MAPK pathway in IECs. After being activated by amino acids, mTOR signaling could inhibit autophagy.