Vitamin C / ascorbic acid: Sources, Daily requirement, Functions, and Deficiency || Usmle |
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📌𝐅𝐨𝐥𝐥𝐨𝐰 𝐨𝐧 𝐈𝐧𝐬𝐭𝐚𝐠𝐫𝐚𝐦 :-
https://www.instagram.com/drgbhanuprakash Vitamin C / ascorbic acid: Sources, Daily requirement, Functions, and Deficiency manifestations Ascorbate. Water-soluble, cofactor for enzymatic reactions • Anti-oxidant properties, guards against oxidative stress • Vit C serves as a cofactor for prolyl-4-hydroxylase and lysyl hydroxylase, an enzyme involved in collagen synthesis. • Stable collagen cannot form without proline and lysine hydroxylation. This hydroxylation takes place in the ER. • Hydroxylation of proline secures the collagen chains in triple-helix formation. • The subsequent hydroxylation of lysine is required for cross-linking. • Deficiency of lysyl hydroxylase: Ehlers-Danlos Syndrome Type 6 Other roles: Cofactor for dopamine hydroxylase (dopamine → norepinephrine) Required for reduction of iron from Fe3+ → Fe2+, allowing absorption in the duodenum. Deficiency → scurvy. |