Muscular dystrophy experimental

Jackson, M.J., Kaiser, K., Brooke, M.H. and Edwards, RH.T. (1991). Glutathione depletion during experimental damage to skeletal muscle and its relevance to Duchenne muscular dystrophy. Clin. Sci. 80, 559-564. 

The signs of a vitamin E deficiency may be quite different in animals and humans. The signs occurring in experimental animals indude impaired reproduction and muscle weakness (muscular dystrophy). Reproductive defects in female animals involve a failure of the fetus to thrive. In males, the deficiency results in an inhibition of sperm production. One feature common to humans and animals is the formation of lesions (pathological structures) in nerves and muscles. The deficiency can cause the degeneration of nerves and the accumulation of a compound called lipofuscin in various tissues, such as muscle. Lipofuscin has an amorphous structure and is thought to be composed of lipid degradation products and croSS linked proteins. 

Studies with animals have revealed an interesting pattern of relahorLships involving Se and vitamin E nutrition. In chicks, experimentally induced deficiencies in both S5e and vitamin E result in exudative diathesis, muscular dystrophy, and pancreatic atrophy. The first two problems can be prevented by vitamin E... 

In the last ten to fifteen years it has become apparent that enzootic disease of the muscles of sheep and cattle causes considerable economic loss. Muscular dystrophy of sheep and of cattle has been recorded in many countries, including all European countries, Russia, Japan, Canada, the United States, New Zealand, Australia, and South Africa. As economic problems, enzootic dystrophies are particularly serious in Scotland, Sweden, Finland, New Zealand, parts of Italy, and areas of America bordering on the Rocky Mountains. The remainder of this paper is concerned with the role of vitamin E and of other factors in the etiology of muscular dystrophy. It is important to deal separately with what may be called the experimental dystrophies of cattle and sheep and the enzootic ones. The... 

It has been shown in two independent experiments with lambs that the enzootic muscular dystrophies are not prevented by giving N-diphenyl-p-phenylenediamine, one of the antioxidants which prevents the experimental disease (Safford et al., 1956 Hogue, 1958). Earlier work in which large amounts of ascorbic acid were given to sheep showed that this antioxidant, which has a slight activity in preventing the experimental disease, had no effect on the natural one. 

For t,his reason, the unsaturated fatty acids in foodstuffs have assumed a central place in current work on hepatosis dietetica and muscular dystrophy in pigs at our institute. Etiological studies have been based upon the amounts of the polyunsaturated fatty components present and their stability to oxygen in the diet and also on the tocopherol content of the foodstuffs. We can best describe our results by giving a brief account of some pertinent experimental studies. 

As an agent essential to cellular respiration. Alphato-copherol appears to be necessary in cellular respiration, primarily in heart and skeletal muscle tissues. Thus, muscular dystrophy has been produced experimentally in various animals on E-deficient rations however, vitamin E supplements have not been effective in treating people with muscular dystrophy. 

Engel WK. (1973) Duchenne muscular dystrophy a histologically based ischemia hypothesis and comparison with experimental ischemia myopathy. In Pearson CM, Mostofi FK (eds). The Striated Muscle. Williams Wilkins Co, Baltimore, vol. 12, pp. 45 3-472. 

Vitamin E was discovered as the antisterility factor of the female rat. Deficiency in experimental animals results mainly in atrophy of the testes and dystrophy of muscles. In man, a deficiency disease is not knoiMi some authors, however, suspect that muscular dystrophy may be connected with vitamin E deficiency. 

A decreased ability of the sarcoplasmic reticulum to accumulate calcium has been reported in muscular dystrophy in both human [108] and mouse [109] and in some other human muscle diseases [108], although not in myotonic dystrophy [110] the slow relaxation rate in the latter condition appears, therefore, to be due to other causes. After experimental denervation in the rat an increase in calcium-accumulating ability has been reported [111] both in fast and slow muscle, particularly the latter. 

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