Nutrient absorption pathways

Nutrient absorption pathways" is not a specific molecule or receptor but rather refers to the collective physiological and molecular mechanisms by which digested nutrients are transported from the lumen of the gastrointestinal tract into the body. These pathways involve multiple types of transport processes—active transport, passive diffusion, facilitated diffusion, co-transport (secondary active transport), and endocytosis—across specialized epithelial cells in the small intestine called enterocytes. Different classes of nutrients (carbohydrates, proteins/amino acids/peptides, lipids/fatty acids/glycerol/cholesterol) utilize distinct sets of membrane-bound transporter proteins or channels for absorption. The process is highly regulated by neural and hormonal signals as well as interactions with gut microbiota. Disruption in these pathways can lead to malabsorption syndromes or nutritional deficiencies[1][2][3][4][5]. > "The mechanical and digestive processes have one goal: to convert food into molecules small enough to be absorbed by the epithelial cells of the intestinal villi... Absorption can occur through five mechanisms: active transport, passive diffusion, facilitated diffusion, co-transport (or secondary active transport), and endocytosis."[1] Because "Nutrient absorption pathways" does not refer to a single defined molecular target such as a receptor or enzyme but instead encompasses many different molecules and cellular processes involved in nutrient uptake from the gut lumen into circulation or lymphatics[1][2], it should not be considered a canonical therapeutic target. If you need structured information on specific components within these pathways—such as individual nutrient transporter proteins (e.g., SGLT1 for glucose), enzymes involved in digestion prior to absorption (e.g., lactase), or regulatory receptors/hormones—please specify which molecule/receptor you are interested in.