The use of transgenic mouse models of amyotrophic lateral sclerosis in preclinical drug studies.

The discovery of mutations in the human SOD1 gene encoding Cu,Zn superoxide dismutase (Cu,Zn SOD) in patients with familial amyotrophic lateral sclerosis (ALS) has made possible the development of etiological models of the disease. Expression of mutant SOD1 genes in transgenic mice causes a progressive paralytic disease whose general features resemble ALS in humans. We have used the transgenic model to explore etiological mechanisms and to screen potential therapeutics. Our results and those of others show that familial ALS mutations cause a gain-of-function in Cu,Zn SOD that enhances the generation of damaging oxygen radicals. This may render motor neurons sensitive to the excitotoxic effects of ambient glutamate, as a putative glutamatergic inhibitor such as riluzole has therapeutic efficacy both in the transgenic model and in human ALS. This finding highlights the utility of the SOD1-G93A transgenic mouse model for preclinical drug studies in ALS.