Vitamin D and skeletal muscle tissue and function.
This review aims to summarize current knowledge on the role of vitamin D in skeletal muscle tissue and function. Vitamin D deficiency can cause a myopathy of varying severity. Clinical studies have indicated that vitamin D status is positively associated with muscle strength and physical performance and inversely associated with risk of falling. Vitamin D supplementation has shown to improve tests of muscle function, reduce falls, and possibly impact on muscle fiber composition and morphology in vitamin D deficient older adults. Molecular mechanisms of vitamin D action on muscle tissue include genomic and non-genomic effects via a receptor present in muscle cells. Genomic effects are initiated by binding of 1,25-dihydroxyvitamin D [1,25(OH)(2)D] to its nuclear receptor, which results in changes in gene transcription of mRNA and subsequent protein synthesis. Non-genomic effects of vitamin D are rapid and mediated through a cell surface receptor. Knockout mouse models of the vitamin D receptor provide insight into understanding the direct effects of vitamin D on muscle tissue. Recently, VDR polymorphisms have been described to affect muscle function. Parathyroid hormone which is strongly linked with vitamin D status also may play a role in muscle function; however, distinguishing its role from that of vitamin D has yet to be fully clarified. Despite the enormous advances in recent decades, further research is needed to fully characterize the exact underlying mechanisms of vitamin D action on muscle tissue and to understand how these cellular changes translate into clinical improvements in physical performance.
Ceglia
Lisa
L
Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Bone Metabolism Laboratory, 711 Washington Street, Boston, MA 02111, USA. lisa.ceglia@tufts.edu
D000818:Animals; D016678:Genome / Q000235:genetics; D006801:Humans; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000378:metabolism; D011110:Polymorphism, Genetic / Q000235:genetics; D018167:Receptors, Calcitriol / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D014807:Vitamin D / Q000378:metabolism*
D010281:Parathyroid Hormone; D018167:Receptors, Calcitriol; D014807:Vitamin D