Ribosomal protein synthesis in Duchenne muscular dystrophy

Incorporation of a mixture of radioactive amino acids by polyribosomes from muscle extracts of 10 patients with Duchenne muscular dystrophy was over 5-fold higher than 10 normal controls; yet the ribosome content relative to noncollagen protein was the same for both groups. Heavy polyribosomes from the dystrophic muscle produced 4- to 5-fold more collagen than identical control fractions. The extent of collagen synthesis by the dystrophic heavy polyribosomes depended on whether a complementary soluble enzyme came from the patients or from the controls. Supplementation of the dystrophic heavy polyribosomes with normal soluble enzymes restored the synthesis of collagen to that of the controls. This suggests that a substance(s) in the soluble fraction may have the potential for arresting the progressive development of connective tissue in patients with Duchenne muscular dystrophy.