Vitamin A

Although serum levels of vitamin A are usually normal in chronic alcoholics, liver retinoids are progressively lowered through the stages of alcoholic liver disease.

Retinoids may play a central role in hepatic function, where vitamin A is stored as retinyl esters in fat-storing transitional Ito cells. The process of transformation of Ito cells to collagen-producing, hepatic stellate cells is associated with depletion of retinyl esters, which may be implicated in the development of alcoholic liver disease. The causes of vitamin A deficiency in alcoholic liver disease include malabsorption, which is due to decreased secretion of bile and pancreatic enzymes necessary for the digestion of dietary retinyl esters and their incorporation into water-soluble micelles prior to intestinal transport. In addition, the transport of retinol is impaired due to decreased hepatic production of retinol-binding protein. Thirdly, the metabolism of alcohol induces microsomal enzymes that promote the production of polar retinol metabolites, which are more easily excreted in the bile. The signs of vitamin A deficiency include night blindness with increased risk of automobile accidents and increased risk of esophageal cancer due to abnormal squa-mous cell cycling. Conversely, patients with alcoholic liver disease are more susceptible to vitamin A hepatotoxicity so that supplemental doses should be used with caution.

Alcohol No More

Alcohol No More

Do you love a drink from time to time? A lot of us do, often when socializing with acquaintances and loved ones. Drinking may be beneficial or harmful, depending upon your age and health status, and, naturally, how much you drink.

Get My Free Ebook


Post a comment