cholecalciferol and Infections

Autophagy is an essential catabolic program that forms part of the stress response and enables cells to break down their own intracellular components within lysosomes for recycling. Accumulating evidence suggests that autophagy plays vital roles in determining pathological outcomes of immune responses and tumorigenesis. Autophagy regulates innate and adaptive immunity affecting the pathologies of infectious, inflammatory, and autoimmune diseases. In cancer, autophagy appears to play distinct roles depending on the context of the malignancy by either promoting or suppressing key determinants of cancer cell survival. This review covers recent developments in the understanding of autophagy and discusses potential therapeutic interventions that may alter the outcomes of certain diseases.

Topics: Adaptive Immunity; Animals; Autoimmune Diseases; Autophagy; Benzylisoquinolines; Cholecalciferol; Humans; Immune System Diseases; Immunity, Innate; Indoles; Infections; Isoquinolines; Lysosomes; Maprotiline; Metformin; Neoplasms; Phenols; Pyrroles; Resveratrol; Sirolimus; Spermidine; Stilbenes; Tetrahydroisoquinolines; Trehalose

The prevalence of vitamin D deficiency in hemodialysis patients is high. While most hemodialysis patients are treated with activated vitamin D (1,25[OH]2D) to prevent renal osteodystrophy, clinical practices of the screening and treatment of 25(OH)2D deficiency are highly variable. It is unclear if nutritional vitamin D supplementation with D2 or D3 provides an additional clinical benefit beyond that provided by activated vitamin D treatment in this population.. We will conduct a systematic review of nutritional vitamin D (D2/D3) supplementation and health-related outcomes in hemodialysis patients according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The primary objective is to assess the impact of nutritional vitamin D supplementation on clinical outcomes relevant in hemodialysis patients, such as mortality, cardiovascular events, infections, and fractures. Secondary outcomes will include anemia, hyperparathyroidism, medication use (erythrocyte-stimulating agents, activated vitamin D), and quality of life. We will search MEDLINE, Scopus, Web of Science, and ClinicalTrials.gov for randomized, controlled trials of nutritional vitamin D supplementation (ergocalciferol/D2 or cholecalciferol/D3) in chronic hemodialysis patients. The Cochrane Risk Assessment Tool will be used to assess the quality of eligible studies. We will perform meta-analyses using standard techniques for the outcomes listed above if pooling is deemed appropriate/sufficient. The results of this systematic review may highlight gaps in our knowledge of the relevance of nutritional vitamin D in end-stage renal disease, allowing for the informed design of clinical trials assessing the impact of nutritional vitamin D therapy in the hemodialysis population in the future.. PROSPERO CRD42014013931.

Topics: Cardiovascular Diseases; Cholecalciferol; Chronic Kidney Disease-Mineral and Bone Disorder; Clinical Protocols; Dietary Supplements; Ergocalciferols; Fractures, Bone; Humans; Infections; Renal Dialysis; Renal Insufficiency, Chronic; Research Design; Systematic Reviews as Topic; Vitamin D Deficiency; Vitamins

Vitamin D3 is a key regulator of vertebrates homeostasis. It is synthesized from the precursor 7-dehydrocholesterol upon UVB exposure in the skin and then hydrolyzed in the liver in position 25, to be finally converted into its active form, 1,25-dihydroxyvitamin D (1,25(OH)2D or calcitriol), in the kidneys. The biological activity of this molecule depends on its binding to the nuclear receptor VDR, which binds VDRE once complexed with RXR-alpha. Despite being present in different types of food, the best way to assume it at physiological levels remains the exposure to UVB radiation at certain hours of the day and at particular angles of the Earth's crust. There is plenty of evidence that altered levels of vitamin D3 are associated with pathological conditions, such as osteoporosis, cancer, immunological and infectious diseases. In this review, we discuss vitamin D3 metabolism, its role in several diseases and the link between vitamin D3 and immune cells.

Topics: Animals; Cholecalciferol; Humans; Infections; Neoplasms; Osteoporosis; Skin

Airway inflammation in asthma is characterized by activation of T helper type-2 (Th2) T cells, IgE production and eosinophilia. In many cases, this process is related to an inappropriate T cell response to environmental allergens, and other T cell-dependent pathways may also be involved (such as Th17). Regulatory T cells (Tregs) are T cells that suppress potentially harmful immune responses. Two major subsets of Treg are CD25(hi), Foxp3(+)Tregs and IL-10-producing Tregs. There is evidence that the numbers or function of both subsets may be deficient in patients with atopic allergic disease. Recent work has extended these findings into the airway in asthma where Foxp3 expression was reduced and CD25(hi) Treg-suppressive function was deficient. In animal models of allergic airways disease, Tregs can suppress established airway inflammation and airway hyperresponsiveness, and protocols to enhance the development, recruitment and function of Tregs have been described. Together with studies of patients and in vitro studies of human T cells, these investigations are defining potential interventions to enhance Treg function in the airway in asthma. Existing therapies including corticosteroids and allergen immunotherapy act on Tregs, in part to increase IL-10 production, while vitamin D3 and long-acting beta-agonists enhance IL-10 Treg function. Other possibilities may be enhancement of Treg function via histamine or prostanoid receptors, or by blocking pro-inflammatory pathways that prevent suppression by Tregs (activation of Toll-like receptors, or production of cytokines such as IL-6 and TNF-alpha). As Tregs can also suppress the potentially beneficial immune response important for controlling infections and cancer, a therapeutic intervention should target allergen- or site-specific regulation.

Topics: Adrenal Cortex Hormones; Allergens; Animals; Asthma; Cholecalciferol; Cytokines; Forkhead Transcription Factors; Humans; Immunotherapy; Infections; Inflammation; Lymphocyte Activation; Neoplasms; Receptors, Prostaglandin; T-Lymphocytes, Regulatory; Th2 Cells; Vitamins

We assessed the effect of vitamin D supplementation on related biochemistry, infection and dentition of the infant. In a double-blind, placebo-controlled trial conducted in Lucknow, India (latitude 26°N), 230 mother -newborn pairs were randomised to receive, for 9 months, 3000µg/month oral vitamin D3 by the mother (group A) or 10µg/d by the infant (group B) or double placebo (group C). All babies received 15 min of sun exposure (unclothed) during massage. Infants' median 25-hydroxyvitamin D (25(OH)D) was lower in group C (median 45·3; interquartile range (IQR) 22-59·5 nmol/l) than in groups A (median 60·8; IQR 41·3-80·5 nmol/l (P7.5µkat/l) was significantly more frequent in group C babies (16 %) than in group A (4 %) or group B (0 %) babies. The number of days with respiratory or diarrhoeal infection by 9 months of age was higher in group C (median 46·5; IQR 14·8-73·3 d) than in group A (median 18·5; IQR 8·8-31·0 d (P<0·01)) or group B (median 13·0; IQR 7·0-28·5 (P<0·05)). We conclude that monthly maternal or daily infant supplementation with vitamin D along with sun exposure is superior to sun exposure alone in maintaining normal infant 25(OH)D at 3·5 months, and provide protection from elevated alkaline phosphatase and infectious morbidity.

Topics: Cholecalciferol; Dietary Supplements; Female; Humans; Infant; Infant Formula; Infant Nutritional Physiological Phenomena; Infant, Newborn; Infections; Lactation; Male; Maternal Nutritional Physiological Phenomena; Milk, Human; Risk Factors; Sunlight; Vitamin D