Vitamin D levels and potential impact in systemic sclerosis.
Vitamin D is essential not only for calcium and bone metabolism, but it also may exert other biological activities, including immunomodulation through the expression of vitamin D receptor in antigen-presenting cells and activated T cells. Evidence from animal models and human prospective studies of rheumatoid arthritis, multiple sclerosis, type I diabetes, and systemic lupus erythematosus, indeed suggested an important role for vitamin D as a modifiable environmental factor in autoimmune diseases. In systemic sclerosis (SSc), this role has not been completely dissected, although recent studies clearly evidenced a high prevalence of vitamin D deficiency. Moreover, some degree of association between vitamin D deficiency and disease activity or phenotype characteristics has also been observed. Vitamin D deficiency in SSc may be related to several factors: insufficient sun exposure due to disability and skin fibrosis, insufficient intake because of gut involvement and malabsorption. Although it is advisable to regularly check vitamin D status in these patients, there is no consensus about which vitamin D supplementation regimen might be sufficient to modulate immunological homeostasis, and possibly reduce disease activity or severity, thus further prospective studies are needed. Moreover, novel vitamin D analogues with more pronounced immune modulatory effect and lower activity on calcium metabolism are in the pipeline, and might represent a great innovative opportunity for the treatment of vitamin D deficiency in such autoimmune disorders.
University of Cagliari, A.O.U. of Cagliari, Italy. ales.vacca@tiscali.it
Alessandra
A
Vacca
Catherine
C
Cormier
Alessandro
A
Mathieu
André
A
Kahan
Yannick
Y
Allanore
D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology / Q000628:therapy; D019587:Dietary Supplements; D004195:Disease Models, Animal; D006801:Humans; D007155:Immunologic Factors / Q000008:administration & dosage; D012595:Scleroderma, Systemic / Q000097:blood / Q000276:immunology* / Q000628:therapy; D014807:Vitamin D / Q000008:administration & dosage / Q000097:blood / Q000502:physiology; D014808:Vitamin D Deficiency / Q000097:blood / Q000276:immunology* / Q000628:therapy
D007155:Immunologic Factors; D014807:Vitamin D