Vitamin A (Retinol) Biochemistry
Summary
Vitamin A is a group of fat-soluble compounds that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids (notably beta-carotene) found in leafy greens. Vitamin A is an antioxidant, and it has a number of functions. These functions include growth and development, cell differentiation and immune maintenance, the formation of visual pigments, and the treatment of acne (isotretinoin) and measles. ATRA (all-trans retinoic acid), a form of vitamin A, is used to treat the APL, also known as acute promyelocytic leukemia (subtype of AML).
Key Points
- Retinol (Vitamin A)
- Antioxidant found in:
- Wild game/animal products, especially liver (preformed vitamin A)
- Leafy vegetables (as beta-carotene precursor)
- Fat-soluble
- Fat malabsorption in biliary/pancreatic insufficiency (e.g. cystic fibrosis) can cause Vitamin A Deficiency
- Constituent of retinal visual pigments
- Deficiency or excess can affect vision
- Maintains normal cell differentiation
- epithelial cells into specialized tissue (pancreatic cells, mucus-secreting cells)
- prevents squamous metaplasia
- Promyelocytes into mature granulocytes
- Mechanism of action for treating APL (subtype of AML)
- epithelial cells into specialized tissue (pancreatic cells, mucus-secreting cells)
- Inhibits sebum production in sebaceous glands
- used to treat cystic acne
- Also used to treat measles
- Antioxidant found in:
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