- 1. Dietary lipids enter stomach intact
- 2. Lingual/gastric lipase hydrolyze medium/short-chain FAs from ONLY TGs from sn-3 position --> DGs.
3. TAG, DAG, C, CE, and PL --> SI + bile salts --> micelles
4. Pancreatic/intestinal enzymes act on micelles
5. Short-chain FAs move directly into portal vein toward liver.
6. Glycerol, long-chain FAs, cholesterol are absorbed into enterocyte with help of transfer proteins (does NOT require energy!)
MAG, DAG, and lysophosphatides are absorbed into enterocyte via diffusion.
7. Enterocyte ER - DAGs + MAGs + FFAs --> TAGs, lysophsophatides + FA --> phosphatidic acid, C --> CE.
8. Reformed lipids, along with ApoB48, form chylomicron that leaves enterocyte by endocytosis into lymph. Other apolipoproteins are transferred to chylomicrons from other lipoprotein complexes.