Vitamin A and retinoids in antiviral responses.
Vitamin A deficiency results in multiple derangements that impair the response to infection. This review focuses on experimental models of specific virus infections and on cytokines and cells with cytolytic activity important to antiviral defenses.
Altered specific antibody responses and greater epithelial damage in vitamin A-deficient hosts are consistent findings. The cytolytic activity on natural killer cells and various cytokine responses are altered. The inflammatory response to infection may also result in derangements in the transport and metabolism of retinol. We speculate that interaction of several factors may combine to explain the greater severity of infection seen in vitamin A-deficient animals and children.
In addition to a preexisting lack of tissue vitamin A, these factors may include reduced mobilization and increased excretion of retinol during the response to infection, poor innate and specific immune response to virus, and delayed repair of damaged epithelia. Foci of vitamin A-deficient epithelia may be sites of penetration of bacteria and other agents, leading to secondary infections and poor outcome in vitamin A-deficient animals and humans.
Commentary by Dr. Calapai
Vitamin A is an extremely important nutrient for virtually all areas of the human body. It has some interesting significance in respect to immune function and maintenance.The series of events that revolve around response to infection are complex and are dependent in part on Vitamin A. Deficiency has been linked to decreases in circulation of antibodies and killer cells. Throughout our lives we are exposed to a wide range of infectious agents, some that are benign , yet others that are linked to cancer and heart disease. We will always neeed to have a strong immune response to be able to overcome these.
Vitamin A should be present in a good , comprehensive multivitamin. It should be taken roughly 3 times a day to help to maintain appropriate blood levels.
Click here to see Optimal Health Product's …