Increased [35S]glutathione binding sites in spinal cords from patients with sporadic amyotrophic lateral sclerosis

Recent observations have suggested abnormalities in the gene for superoxide dismutase (SOD1) in patients with the familial form of amyotrophic lateral sclerosis (ALS). As SOD activity has secondary effects on glutathione (GSH), we have evaluated [35S]GSH binding in spinal cord sections from patients who died with sporadic ALS and control subjects. [35S]GSH binding sites were present in the grey matter of spinal cords in both the dorsal and ventral horns. ALS patients showed significantly increased [35S]GSH binding (+16%) in the dorsal and ventral grey horns compared to controls. Scatchard analysis of saturation binding data revealed that increased [35S]GSH binding was due to changes in the number rather than the affinity of GSH binding sites. These findings add support to a role for GSH in the mechanism loading to the pathogenesis of sporadic ALS.