Water-Soluble Vitamins (Kaplan) Flashcards
What 3 enzymes require biotin? Pathways?
Pyruvate carboxylase - gluconeogenesis
Acetyl-CoA carboxylase - FA synth
Propionyl-CoA carboxylase - VOMIT
What are the substances metabolized by propionyl-CoA?
VOMIT
Val, Odd-chain FAs, Met, Ile, Thr
What is the most common cause of biotin deficiency?
daily consumption of raw eggs
What 2 enzymes of glucose metabolism require thiamine?
pyruvate d.h. and α-ketoglutarate d.h.
What is the cardiac pathology in wet beriberi?
dilated cardiomyopathy –> decreased EF
What enzyme’s function is tested to Dx thiamine deficiency? Why?
transketolase - Thiamine is the only cofactor it requires.
What dehydrogenase (not directly involved in the metabolism of glucose) requires thiamine?
branched-chain amino acid d.h.
What 5 cofactors are required by all α-keto acid dehydrogenases?
LIly is so PO' she ATE Fried Chicken Nuggets with Thugs. Lipoate FAD CoA NAD+ TPP
What are the main Sx of pellagra?
3 D’s
Diarrhea, Dementia, Dermatitis
Progressive peripheral neuropathy caused by thiamine deficiency is due to damage in what part of the CNS?
posterior and lateral columns of spinal cord
What vitamin must be taken w/ isoniazid therapy?
B6
What is the most common cause of B6 deficiency?
alcoholism
How does alcoholism cause B6 deficiency?
Hepatitis -> increased transaminase activity; transaminases require B6.
How does B6 deficiency cause a microcytic sideroblastic anemia?
B6 is required by δ-ALA synthase for hemesynthesis. No B6, no heme, iron builds up, sideroblastic anemia.
You can see B6 deficiency right on someone’s face. How?
Stomatitis, cheilosis
