| Theme |
Frontiers in Vitamin D Action |
| Title |
Effect of vitamin D on skeletal muscle |
| Author |
Itsuro Endo |
First Department of Internal Medicine, School of Medicine, The University of Tokushima |
| Author |
Daisuke Inoue |
First Department of Internal Medicine, School of Medicine, The University of Tokushima |
| Author |
Toshio Matsumoto |
First Department of Internal Medicine, School of Medicine, The University of Tokushima |
| [ Summary ] |
Patients with vitamin D insufficiency or resistance often exhibit muscle weakness and/or atrophy. However, its molecular mechanism is largely unknown. Vitamin D receptor (VDR) is known to be expressed at the early stages of myoblasts and myotubes during muscle differentiation. The direct effects of vitamin D on skeletal muscle cells include induction of calbindins and transcription factors, such as c-myc and c-fos (genomic actions); and activation of Ca channels, c-Srk tyrosine kinase and MAP kinase (non-genomic actions). Recent studies on VDR gene knockoutmice, revealed that VDR is also involved in regulation of the MyoD family of transcription factors during the course of muscle differentiation. Thus, vitamin D appears to regulate proliferation, differentiation, maturation and function of skeletal muscle through these complex actions. |