Injuries to the skeletal muscle occur during contact sports, prolonged exercise, or car crashes. The basic sequence of cellular events during regeneration after major injury is primary inflammation phase, followed by cell proliferation and cell death (apoptosis), and then followed by scar tissue formation. Therapeutic approaches to enhance recovery from muscle injury focus on strategies to limit necrosis, reduce fibrosis, and suppress excessive inflammation of the injured tissue. However, the effect size of such treatments is minimal.
Recently, Dr Ioannis Stratos and colleagues of the University of Rostock in Germany purposefully injured rats and then gave them truly massive doses of vitamin D, exactly 332,000 IU/kg as a single oral dose in their food, which is about 32,000 IU for a 100 gram rat.
Stratos I, Li Z, Herlyn P, Rotter R, Behrendt AK, Mittlmeier T, Vollmar B. Vitamin D Increases Cellular Turnover and Functionally Restores the Skeletal Muscle after Crush Injury in Rats. Am J Pathol. 2012 Dec 19.
They found that the vitamin D treated rats caused a significant increase in cell proliferation and a significant inhibition of apoptosis at day four after injury compared to control animals. There was an increase in an enzyme that indicated an increase in extracellular matrix proteins. After 42 days, this cellular turnover resulted in a faster recovery in the vitamin D group compared to the rats that received placebo.
The authors concluded,
“Current research on the biological effects of vitamin D opens new therapeutic alternatives, in addition to osteoporosis therapy or cancer prevention. These alternatives include restoration and faster healing of injured muscle tissue. Vitamin D could represent an attractive adjuvant therapy that might optimize the restoration of injured skeletal muscle tissue in the future.”