Low serum 24,25 dihydroxyvitamin D in Duchenne muscular dystrophy.

Levels of serum 24,25(OH)2D3 (0.69 +/- 0.17 ng/ml) were lower in DMD patients than in age-matched controls (2.13 +/- 0.15 ng/ml). Circulating levels of 1,25(OH)2D3 and 25(OH)D3 were within the accepted normal range. Bearing in mind the proposed pathophysiologic role of calcium in DMD and the influence of vitamin D metabolites on muscle ATP and protein synthesis, as well as on sarcoplasmic reticulum calcium transport and muscle mitochondrial calcium content, the above findings of low or deficient 24,25(OH)2D3 levels in DMD could be meaningful from the etiologic and therapeutic points of view.