B1
Thiamine (TPP)
Deficiency: ATP depletion->affects brain and heart first
1. dry beriberi (CNS)-polyneuritis, symmetrical muscle wasting
2. wet beriberi (CV)-high output cardiac failure (dilated cardiomyopathy)
3. Wernicke-Korsakoff-confusion, optholmoplegia, ataxia, memory loss, confabulation, personality change
B3
Niacin (NAD/NADP=3ATP)
tryptophan + B6-->niacin-->NAD/NADP
Deficiency:
(Hartnup disease--dec absorption tryptophan--treat w/ oral niacin)
(carcinoid--inc tryptophan metabolism)
(Isoniazid)
1. Glossitis
2. Pellegra: Diarrhea, Dementia, Dermatitis
S/E: facial flushing (used for hyperlipidemia)
B6
pyridoxine (PLP) cofactor in transamination (ALT, AST), heme synthesis, decarboxylation rxns, glycogen phosphorylase
Deficiency: (Isoniazid, oral BC)
sideroblastic anemia
B12
cobalamin-->cofactor for homocystein methyltransferase
found in meat and years stored in liver
Deficiency: build up of homocysteine and methylmalonyl-CoA; macrocytic anemia with neurologic defects (prolonged is irreversible damage); due to malabsorption (EtOH, sprue, pernicious anemia, Crohns, gastric bypass, Diphyllobothrium latum)
Schilling test to detect pernicious anemia
Folate
converts to THF (tetrahydrofolate)-->coenzyme for 1 carbon transfer/methylation
synthesis of nitrogen bases
Deficiency: macrocytic anemia w/o neurologic symptoms (EtOH, pregnancy)
A
fat soluble
antioxidant
vision (pigments), differentiation of epithelial cells
Deficiency: night blindness, dry skin
Toxicity: teratogenic (Isotretinoin)
D
D3 (from milk or made in from sunlight in skin)->25-OHD3 (storage form made in liver, bound to plasma proteins)->1,25-OH2D3 (active form made in kidney)
1. increase Ca++ and phosphate reabsorption in kidneys
2. increase Ca++ and phosphate reabsorption in gut
3. inc bone resorption-->remodeling, mineralization
Deficiency:
1. Rickets/Osteomalacia
2. (extracellular) hypocalcemia-->hyperreflexia
TPP
1. pyruvate dehydrogenase (glycolysis)
2. alpha-ketoglutarate dehydrogenase (TCA)
3. transketolase (HMP shunt)
4. Branched-chain AA dehydrogenase