Vit B12 (cobalamin) is an essential co-factor and co-enzyme in many biochemical reactions, including synthesis of DNA , methonine and succinyl Co-A. Vit B12 def causes anaemia, neurological disease, dementia and oesteoporosis.
What is the most important physiological factor in ensuring adequate cobalamine intake:
1-Bile acid secretion
2-Duodenla absorption
3-High gastric pH
4-Pancreatic protease secretion
5-Transcobalamin-1 binding
What is the most important physiological factor in ensuring adequate cobalamine intake:
1-Bile acid secretion
2-Duodenla absorption
3-High gastric pH
4-Pancreatic protease secretion
5-Transcobalamin-1 binding
 |
| B12 metabolism |
Dietary Vit B12 = cobalamin+protein
Cobalamin is released from food by action of pipsen
R-protien from preatal cells coupled with cobalamin to prevent degradation by acid
In the duodenum the R/Cbl is uncuopled by the action pancreatic enzymes to join IF and move down to the TI.
Vit B12 is a water soluble vitamin
It is not made by the body, the only source being dietary 2-3 mcg a day
Total body stores is 2-5 gm, def takes 3-5 years to become apparent .
Causes of B12 def:
1-Poor dietary intake ; vegan, alcoholics and elderly
2-Gastric causes: autoimmune gastritis, PA, atrophic gastritis and surgical gastrectomy
3-Small bowel causes: CD, SBBO, TI resection
4-Medications: metformin, NO
NB chronic leukemias causes rise level of B12
source: egg, meat poultry, shelfish, milk amd milk products
A 48-year-old woman with chronic pancreatitis due to gallstones is noted to have a macrocytic anaemia.
ReplyDeleteWhat is the most likely cause of the anaemia?
1- Bone marrow dysfunction
2-Folate deficiency
3-Hyposplenism
4-Hypothyroidism
5-Vitamin B12 deficiency
Chronic pancreatitis and the resultant pancreatic insufficiency results in the failure of splitting of dietary B12 from R-binders,a reaction that requires trypsin.
This inhibits the binding of intrinsic factor to the vitamin B12 so it is not absorbed.
I was diagnosed as HEPATITIS B carrier in 2013 with fibrosis of the
ReplyDeleteliver already present. I started on antiviral medications which
reduced the viral load initially. After a couple of years the virus
became resistant. I started on HEPATITIS B Herbal treatment from
ULTIMATE LIFE CLINIC (www.ultimatelifeclinic.com) in March, 2020. Their
treatment totally reversed the virus. I did another blood test after
the 6 months long treatment and tested negative to the virus. Amazing
treatment! This treatment is a breakthrough for all HBV carriers.