Ethanolamine Metabolism in the Mammalian Gastrointestinal Tract: Mechanisms, Patterns, and Importance

Nutritional exchanges and cooperation between bacteria in the gastrointestinal tract and the mammalian host play an important role in health and disease. Ethanolamine is an essential dietary lipid nutrient for animals and is abundant in both intestinal and bacterial cell membranes. Ethanolamine can be utilized by intestinal eukaryotic cells via the cytidine phosphoethanolamine pathway for de novo synthesis of phosphatidylethanolamine, and certain bacteria are able to catabolize it as a major carbon and/or nitrogen source with the help of ethanolamine utilization proteins. In addition, ethanolamine utilization dramatically affects lipid metabolism and short-chain fatty acid biosynthesis. Ethanolamine metabolism plays a significant role in the renewal and proliferation of intestinal cells and intestinal inflammation, and ethanolamine may be a nutritional target to diagnose or treat diseases such as inflammatory bowel disease. This review summarizes the mechanisms of ethanolamine metabolism in the mammalian gastrointestinal tract and its influence on intestinal health and immunity, thus providing a theoretical reference for further studies on mammalian nutrition and disease.