Watre soluble vitamin B12 ppt Lecture 5 BIOCHEMISTRY [email protected]

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WATER SOLUBLE VITAMINS Dr Vijay Marakala MBBS.,MD. Assistant Professor BIOCHEMISTRY SIMS & RC

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Transcript of Watre soluble vitamin B12 ppt Lecture 5 BIOCHEMISTRY [email protected]

  • 1. VitaminB12

2. Chemistry It is made up of Tetrapyrrole ring system called as corrin ring with a central cobalt (Co) atom. 3. 3-4 g/day. 4. Vitamin Bl2 combines with intrinsic factor to form Vitamin B12 - IF complex. Vitamin B12 intrinsic factor complex is absorbed in the ileum. In the illeal cells the intrinsic factor is released and the B12 is transferred to a plasma transport protein transcobalamin II. 5. Unlike other water soluble vitamins, vitamin B12 is stored in the liver and other tissues Whole liver contains about 2mg of B12, which is sufficient for 2-3 years. 6. Methyl cobalamin Deoxy adenosylcobalamin 7. Vitamin B12 act as coenzyme. Methyl cobalamin is the coenzyme of methionine synthase . Deoxy adenosylcobalamin is the coenzyme of methyl malonyl-CoA mutase Therapeutic function Vitamin B12 is effective in lowering concentration of plasma homocysteine of coronary artery disease patients. 8. Causes Nutritional Decrease in absorption IF deficiency Gastric atrophy Pregnancy Fish tapeworm 9. Megaloblastic anemia Pernicious anemia Hamatopoitic Numbness and tingling of the hands and feet Subacute combined degeneration Neurological Hyperhomocysteinemia Achlorhydria Others 10. Serum B12 Schilling test Peripheral smear Homosystinuria 11. Thank you |