Multiple sclerosis and vitamin D: an update

Abstract

MS is a chronic, immune-mediated inflammatory and neurodegenerative disease of the central nervous system (CNS), with an etiology that is not yet fully understood. The prevalence of MS is highest where environmental supplies of vitamin D are lowest. It is well recognized that the active hormonal form of vitamin D, 1,25-dihydroxyvitamin D (1,25-(OH) 2 D), is a natural immunoregulator with anti-inflammatory action. The mechanism by which vitamin D nutrition is thought to influence MS involves paracrine or autocrine metabolism of 25OHD by cells expressing the enzyme 1a-OHase in peripheral tissues involved in immune and neural function. Administration of the active metabolite 1,25-(OH) 2 D in mice and rats with experimental allergic encephalomyelitis (EAE, an animal model of MS) not only prevented, but also reduced disease activity. 1,25-(OH) 2 D alters dendritic cell and T-cell function and regulates macrophages in EAE. Interestingly, 1,25-(OH) 2 D is thought to be operating on CNS constituent cells as well. Vitamin D deficiency is caused by insufficient sunlight exposure or low dietary vitamin D 3 intake. Subtle defects in vitamin D metabolism, including genetic polymorphisms related to vitamin D, might possibly be involved as well. Optimal 25OHD serum concentrations, throughout the year, may be beneficial for patients with MS, both to obtain immune-mediated suppression of disease activity, and also to decrease disease-related complications, including increased bone resorption, fractures, and muscle weakness.

Gender Differences in 1,25 Dihydroxyvitamin D3 Immunomodulatory Effects in Multiple Sclerosis Patients and Healthy Subjects

“…These findings converge with experimental evidence indicating a protective effect for vitamin D 3 in animal models of MS. For example, experimental autoimmune encephalomyelitis (EAE) can be prevented by administering the active metabolite 1,25-(OH) 2 D 3 prior to immunization and ameliorated when given after disease onset (18,19). Conversely, vitamin D 3 deficiency decreased the time to EAE onset and increased disease severity (19,20). Interestingly, recent investigations showed that 1,25-(OH) 2 D 3 significantly inhibits EAE in female mice, but not in male mice, and that ovariectomy abrogates this protective effect, suggesting a link between female sex hormones and 1,25-(OH) 2 D 3 metabolism (21).…”

Solar UV exposure in construction workers in Valencia, Spain

“…Appropriate vitamin D levels, besides being required for 6 skeletal health, have also been suggested as beneficial against multiple sclerosis (Kampman et al, 2010;Van Amerongen et al, 2004), cardiovascular disease (Zittermann and Gummert, 2010) and the development of breast, prostate and colon cancers (Gilbert et al, 2009;Grant, 2010;Grant and Holick, 2005;John et al, 2007). In the case of depressive disorders, there is evidence that supports the role of suboptimal vitamin D levels, although the data are not conclusive and further studies are necessary (Humble, 2010).…”

Hypovitaminosis D in Adult - A systemic Review

“…Living at higher latitudes increases the risk of type 1 diabetes, multiple sclerosis, and Crohn's disease 12,13 Living below 35 degrees latitude for the first 10 years of life reduces the risk of multiple sclerosis by approximately 50% 14,15 . Among white men and women, the risk of multiple sclerosis decreased by 41% for every increase of 20 ng per milliliter in 25-hydroxyvitamin D above approximately 24 ng per milliliter (60 nmol per liter) (odds ratio, 0.59; 95% CI, 0.36 to 0.97; P = 0.04).…”