Chapter 24 - Vitamin D Signaling and Skeletal Muscle Cells
Résumé
Besides its classical biological roles in bone health, extraskeletal effects of vitamin D are currently a subject of extensive research. The expression of the vitamin D receptor in most tissues has strengthened arguments for multiple functions, among which the effect of vitamin D on muscle mass and performance has long been discussed. It is now clear that skeletal muscle is one of the body targets of vitamin D. Studies have demonstrated that vitamin D deficiencies are associated with reduced muscle mass and strength. Vitamin D is also involved in muscle regeneration, i.e., vitamin D modulates the proliferation and differentiation of skeletal muscle cells. Vitamin D is also a significant driver of numerous metabolic pathways of muscle cell metabolism. To explain these multiple actions, research has demonstrated a genetic contribution of vitamin D to muscle function, in addition to its genomic and nongenomic effects.
Despite our wide knowledge concerning the action of vitamin D, more studies are still needed to clarify the importance of vitamin D in muscle health and adjust vitamin D treatment more closely to patient characteristics. This would be of direct relevance for older subjects and athletes, and also in situations where muscle mass or function is lost, particularly in chronic illnesses.