Figure 3. Skin fibroblasts from MS patients have reduced resiliency. Skin fibroblasts were cultured in standard media for 24 hours prior to the assay. (A) Cells were treated with 200 μM hydrogen peroxide for two hours followed by incubation with MTT reagent for an additional two hours (Ctrl, n = 16; MS, n = 10; ALS, n = 10). All cells were lysed and the resulting formazan crystals were solubilized prior to measurement. The percent cytotoxicity was determined using a ratio between treated and untreated cells. Each data point represents a unique cell line and is the average of all measurements. The 95% confidence interval is shown. Significance was determined using one-way ANOVA post hoc Tukey test. (B) Skin fibroblasts were treated with 200 μM hydrogen peroxide for ten hours (Ctrl, n = 13; MS, n = 8; ALS, n = 10). Fluorescence data using the CellTox Green assay was measured every hour. Eight unique cell lines per group were used. Percent viability is relative to the one hour time reference. The data represents the average of all measurements with the 95% confidence interval shown. Significance was determined using two-way ANOVA post hoc Tukey test. In (B), * indicates significance between Ctrl and MS, and # for MS and ALS. No significance was determined between Ctrl and ALS. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Abbreviations: ALS, amyotrophic lateral sclerosis; Ctrl, control; H2O2, hydrogen peroxide; MS, multiple sclerosis.