Effects of Nutrition on Growth, Lifespan and Histopathology of Mice with Hereditary Muscular Dystrophy

Abstract

Semisvnthetic rations known to contain high-quality protein and lipid, resulted consistently in increased lifespan and extended the period of growth in strain 129 mice suffering from hereditary, progressive muscular dystrophy, when compared with results obtained with dystrophic mice maintained with a commercial laboratory chow (diet 1). A similar increase in lifespan and improvement in overall health was noted when dystrophic animals were reared with a certain commercial mouse breeder ration of the Morris formula. The addition of 1.5% of glycine to the basal semisynthetic ration temporarily increased the growth rate of dystrophic mice over that of the normal controls. Although many of the gross symptoms appeared to be alleviated, and certain histopathological lesions of mouse dystrophy were altered, there was no remission or cure of the dystrophic condition as observed histologically. Histopathologically, all the improved diets gave the same effects, with no detectable variation in respect to the particular diet or to sex. There was a decrease in the incidence of coagulation necrosis of muscle fiber segments and in the subsequent regenerative activity as compared with these same processes observed in dystrophic animals fed diet 1. Further, much of the regenerative activity was atypical at the cellular level, and, not infrequently, the necrotic zone of a fiber showed connective tissue replacement, without any evidence of previous regenerative activity. The data presented draw attention to the importance of nutritional status when studying strain 129 mice afflicted with hereditary, progressive muscular dystrophy.