Why use Vitamin A, retinol as a diet supplement
Retinol is an active form of Vitamin A, a fat-soluble vitamin that is essential to vision and bone development. Sources of retinol include liver, whole milk and fortified foods. Retinol is one of them; other forms include retinyl palmitate, retinal and retinoic acid. Renova and Retin-A? are retinoic acid, also known as tretinoin. Retinol is basically vitamin A, and in the case of Retinol Cream, it is the purest form of vitamin A available. The company does claim that the retinol is stabilized with antioxidants, which are a good substance for preventing further environmental damage to the skin that free radicals can cause.
Retinol is transported through the blood bound to retinal-binding protein and is stored in the liver bound to a protein. Synthesis of retinal-binding protein is dependent on zinc. Retinol is typically marketed for reduction of the signs of aging such as fine lines and wrinkles. A little insight into how it works, what products to buy and how to use them, as well as other benefits and possible risks will help you decide if retinol is right for you.
Vitamin A and its metabolic derivatives are known to be key signalling molecules in regulating morphogenetic events in vertebrate development. Here we investigated their possible involvement during mammalian kidney development using paired rat metanephros organ culture. Vitamin E and copper topical antioxidants are generally more effective than vitamin C, Pehoushek said, because they are more readily absorbed. Topical vitamin A derivatives, or retinoids, help remove dead skin cells and stimulate production of collagen, believed to soften wrinkles and improve skin tone. Vitamin E is found in almonds, peanuts, sunflower seeds, broccoli, wheat germ and vegetable oils. A powerful antioxidant, it protects your cells against the effects of free radicals, which are potentially damaging by-products of the body?s metabolism.
Retinol-binding protein (RBP) is the sole specific transport protein for retinol (vitamin A) in the circulation, and its single known function is to deliver retinol to tissues. Within tissues, retinol is activated to retinoic acid, which binds to nuclear receptors to regulate transcription of diverse target genes. Retinol cannot communicate with a cell until it has been broken down into retinoic acid. Some of the controversies regarding using retinol in skin-care products have been its stability in skin or in a skin-care product, whether it can be converted into retinoic acid after it is absorbed into the skin, and how much retinol is needed so that as it is changed to retinoic acid there is still enough that can get to the cell. Retinoids are toxic, insoluble in aqueous solutions, and prone to oxidation, and as such they must be bound and protected when within the body. The body uses a variety of chaperones, particularly in the retina, to transport retinoids.
Retinol is active at concentrations equal to its concentration in serum. Retinol is also a requirement for growth in suspension cultures at cell densities of 3 x 10(5)/ml. Retinol is a precursor for a range of signalling molecules that are known to be crucial to the proper development of an embryo. Remarkably, the protein is also unusual in that it is enriched in essential amino acids that the embryo could not synthesise itself. Retinol is one of the main components in oral and topical preparations for treating psoriasis, acne and other skin disorders (for example, rosacea). Eye disorders (for example, cataracts) can also be treated with medications containing retinol, retina and cornea (associated with vitamin A).
