KEGG   PATHWAY: map04977
Entry
map04977                    Pathway                                

Name
Vitamin digestion and absorption
Description
Vitamins are a diverse and chemically unrelated group of organic substances that share a common feature of being essential for normal health and well-being. They catalyze numerous biochemical reactions. Because humans and other mammals cannot synthesize these compounds (except for some synthesis of niacin), they must obtain them from exogenous sources via intestinal absorption. Vitamins are classified based on their solubility in water or fat. Most of the water-soluble vitamins are transported across the small intestinal membrane by carrier-mediated mechanisms, but vitamin B12, cobalamin, is transported by a receptor-mediated mechanism. Intestinal absorption of fat-soluble vitamins requires all of the processes needed for fat absorption. After digestion, these vitamins and the products of pancreatic hydrolysis of triglycerides (TG) are emulsified by bile salts to form mixed micelles which are taken up by intestinal enterocytes and incorporated into chylomicrons (CM). CM are then secreted into the lymphatic system, and finally moves into the plasma.
Class
Organismal Systems; Digestive system
Pathway map
map04977  Vitamin digestion and absorption
map04977

Other DBs
GO: 0051180
Reference
  Authors
Said HM, Mohammed ZM
  Title
Intestinal absorption of water-soluble vitamins: an update.
  Journal
Curr Opin Gastroenterol 22:140-6 (2006)
DOI:10.1097/01.mog.0000203870.22706.52
Reference
  Authors
Basu TK, Donaldson D
  Title
Intestinal absorption in health and disease: micronutrients.
  Journal
Best Pract Res Clin Gastroenterol 17:957-79 (2003)
DOI:10.1016/S1521-6918(03)00084-2
Reference
  Authors
Said HM
  Title
Recent advances in carrier-mediated intestinal absorption of water-soluble vitamins.
  Journal
Annu Rev Physiol 66:419-46 (2004)
DOI:10.1146/annurev.physiol.66.032102.144611
Reference
  Authors
Reidling JC, Nabokina SM, Balamurugan K, Said HM
  Title
Developmental maturation of intestinal and renal thiamin uptake: studies in wild-type and transgenic mice carrying human THTR-1 and 2 promoters.
  Journal
J Cell Physiol 206:371-7 (2006)
DOI:10.1002/jcp.20492
Reference
  Authors
Fujimura M, Yamamoto S, Murata T, Yasujima T, Inoue K, Ohta KY, Yuasa H
  Title
Functional characteristics of the human ortholog of riboflavin transporter 2 and riboflavin-responsive expression of its rat ortholog in the small intestine indicate its involvement in riboflavin absorption.
  Journal
J Nutr 140:1722-7 (2010)
DOI:10.3945/jn.110.128330
Reference
  Authors
Said HM
  Title
Cell and molecular aspects of human intestinal biotin absorption.
  Journal
J Nutr 139:158-62 (2009)
DOI:10.3945/jn.108.092023
Reference
  Authors
Green R
  Title
Ins and outs of cellular cobalamin transport.
  Journal
Blood 115:1476-7 (2010)
DOI:10.1182/blood-2009-12-254037
Reference
  Authors
Zhao R, Matherly LH, Goldman ID
  Title
Membrane transporters and folate homeostasis: intestinal absorption and transport into systemic compartments and tissues.
  Journal
Expert Rev Mol Med 11:e4 (2009)
DOI:10.1017/S1462399409000969
Reference
  Authors
Hediger MA
  Title
New view at C.
  Journal
Nat Med 8:445-6 (2002)
DOI:10.1038/nm0502-445
Reference
  Authors
Harrison EH, Hussain MM
  Title
Mechanisms involved in the intestinal digestion and absorption of dietary vitamin A.
  Journal
J Nutr 131:1405-8 (2001)
DOI:10.1093/jn/131.5.1405
Reference
  Authors
Blomhoff R, Blomhoff HK.
  Title
Overview of retinoid metabolism and function.
  Journal
J Neurobiol 66:606-30 (2006)
DOI:10.1002/neu.20242
Reference
  Authors
Lemaire-Ewing S, Desrumaux C, Neel D, Lagrost L
  Title
Vitamin E transport, membrane incorporation and cell metabolism: Is alpha-tocopherol in lipid rafts an oar in the lifeboat?
  Journal
Mol Nutr Food Res 54:631-40 (2010)
DOI:10.1002/mnfr.200900445
Reference
  Authors
Shearer MJ, Newman P
  Title
Metabolism and cell biology of vitamin K.
  Journal
Thromb Haemost 100:530-47 (2008)
DOI:10.1160/TH08-03-0147
Related
pathway
map04142  Lysosome
map04144  Endocytosis
map04530  Tight junction
map04975  Fat digestion and absorption
map04976  Bile secretion
KO pathway
ko04977   

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