Flashcards in Riboflavin (B2) Deck (12)
An enzyme (flavokinase) phosphorylates riboflavin to form FMN.
Enhanced by magnesium.
Free riboflavin by energy dependent sodium independent carrier RFT2.
Bile facilitates absorption.
FMN dephosphorylated to riboflavin to enter portal blood to go to liver.
Riboflavin carrier proteins (RCP)
Expressed in cells with high metabolic activity.
Pregnancy induces synthesis of RCP's.
Mediate supply of riboflavin to fetus.
1.3 mg men
1.1 mg women
Dehydrogenation and hydroxylation reactions.
B2 in energy production rxns
Oxidative decarboxylation of pyruvate.
Electron transport: succinate dehydrogenase composed of FAD and 3 S atoms.
Fatty acid beta oxidation
B2 in other vitamin metabolism
B6, B12, and folate metabolism.
Niacin from tryptophan (NE).
Reduces glutathione which recycles vitamin C
Ariboflavinosis: Cheilosis (mouth sores), inflamed tongue, neuropathy, weakness.
Rarely deficient in isolation. Usually alongside other deficiency due to being used in metabolism of folic acid, B6, vit K, B12, vit C recycle.
Migraine therapy and cataract prevention.