FIGURE 10.

MND patient fibroblasts are highly sensitive to glutathione depletion in the absence of significant changes in mitochondrial morphology and function. A, electron microscopy of control and MND patient cells (MF1 and MF2) grown under basal conditions illustrates similar mitochondrial morphology. B, cytochrome c oxidase activity is similar in mitochondria freshly isolated from control and MND patient (YS) cells (ns, p = 0.2525; n = 3). C, inhibition of glutathione synthesis has markedly different effects on the viability of control and MND patient cells. YS and control cells were plated at 2000 cells/well density and treated with increasing concentrations of BSO (an inhibitor of glutathione synthase), washed, and stained with 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy-methoxy-phenyl)-2-(4-sulfophenyl)-2H-tetrazolium. Data are mean ± S.D. (n = 3).