We have studied the effect of lysine acetylsalicylate (LAS; Aspegic), a soluble salt of aspirin, on motor deficits in transgenic mice expressing a human superoxide dismutase SOD1 mutation (Gly-93 --> Ala), an animal model of familial amyotrophic lateral sclerosis (FALS). In nontreated FALS mice, motor impairments appear at 12-14 weeks of age, whereas paralysis is not observed before 20 weeks of age. Life expectancy is 140-170 days. Early treatment with LAS from 5 weeks of age delayed the appearance of motor deficits in FALS mice as measured by extension reflex, loaded grid, and rotarod tests. This beneficial effect of treatment was maintained up to 18 weeks of age, until just before onset of end-stage disease. When treatment was started at 13 weeks, no significant beneficial effect was observed. These results demonstrate that chronic LAS treatment is able to delay the appearance of reflex, coordination, and muscle strength deficits in this animal model of ALS if the treatment is started early enough. However, neither the onset of paralysis nor end-stage disease were improved by the LAS treatment. In the absence of an effect on survival, the functional improvement demonstrated here is probably the maximum that this demanding model could allow. Although other properties of LAS may have contributed to its beneficial effect, we suggest that the antioxidant properties of aspirin are responsible for the positive effects in this model and support the use of antioxidants as effective therapy for ALS.
Copyright 1999 Academic Press.