vitamin-d-2 and Communicable-Diseases

As explained in the first part of the article, vitamins and trace elements influence various metabolic functions that are directly related to immune function. In this context, secosteroid vitamin D has met with growing interest. The discussion has focused on whether and, if so, to what extent, vitamin D might contribute to the prevention and possibly the treatment of infections and autoimmune diseases. We know, for instance, that immune cells are capable of synthesizing calcitriol from its precursor calcidiol, whereby the former enhances the synthesis of antibacterial peptides by macrophages while simultaneously inhibiting the (auto)immune response mediated by T helper cells (Th1). Numerous observational studies support the hypothesis that a vitamin D deficit increases the risk of autoimmune diseases such as type 1 diabetes mellitus, multiple sclerosis, psoriasis and rheumatoid arthritis; however, there are few reliable interventional studies to date. In general, immune status represents a sensitive indicator of micronutrient supply. Conversely, the activity of the immune system has an effect on the status of and requirements for nutrients.

Topics: Animals; Ascorbic Acid; Autoimmunity; Communicable Diseases; Dietary Supplements; Ergocalciferols; Humans; Immune System; Inflammation; Inflammation Mediators; Signal Transduction; Vitamin D Deficiency

As elements of the antioxidant system, cofactors of enzymes, components of transcription factors, and epigenetic modulators, micronutrients, such as vitamins and trace elements, influence various metabolic processes that are directly associated with immune functions. Specifically, the vitamins C and D have been shown to have significance immune function. Therefore, the objective of this review is to elucidate interactions between micronutrients and the immune system. In the initial section of this review, we present a general overview of interactions between the immune system and micronutrients, with a focus on the immunobiologically relevant functions of vitamin C. Immune competent cells accumulate vitamin C against a concentration gradient, with a close relationship between vitamin C supply and immune cell activity, especially phagocytosis activity and T-cell function. Accordingly, one of the consequences of vitamin C deficiency is impaired resistance to various pathogens, while an enhanced supply increases antibody activity and infection resistance.

Topics: Animals; Ascorbic Acid; Ascorbic Acid Deficiency; Communicable Diseases; Dietary Supplements; Ergocalciferols; Humans; Immune System; Inflammation; Inflammation Mediators; Signal Transduction

Vitamin D functions in the body through both an endocrine mechanism (regulation of calcium absorption) and an autocrine mechanism (facilitation of gene expression). The former acts through circulating calcitriol, whereas the latter, which accounts for more than 80% of the metabolic utilization of the vitamin each day, produces, uses, and degrades calcitriol exclusively intracellularly. In patients with end-stage kidney disease, the endocrine mechanism is effectively disabled; however, the autocrine mechanism is able to function normally so long as the patient has adequate serum levels of 25(OH)D, on which its function is absolutely dependent. For this reason, calcitriol and its analogs do not constitute adequate replacement in managing vitamin D needs of such patients. Optimal serum 25(OH)D levels are greater than 32 ng/mL (80 nmol/L). The consequences of low 25(OH)D status include increased risk of various chronic diseases, ranging from hypertension to diabetes to cancer. The safest and most economical way to ensure adequate vitamin D status is to use oral dosing of native vitamin D. (Both daily and intermittent regimens work well.) Serum 25(OH)D can be expected to rise by about 1 ng/mL (2.5 nmol/L) for every 100 IU of additional vitamin D each day. Recent data indicate that cholecalciferol (vitamin D(3)) is substantially more potent than ergocalciferol (vitamin D(2)) and that the safe upper intake level for vitamin D(3) is 10,000 IU/d.

Topics: Administration, Oral; Animals; Calcitriol; Cardiovascular Diseases; Cholecalciferol; Communicable Diseases; Diabetes Mellitus; Ergocalciferols; Humans; Kidney Failure, Chronic; Neoplasms; Nutrition Policy; Osteoporosis; Receptors, Calcitriol; Signal Transduction; Vitamin D; Vitamin D Deficiency; Vitamins