Electron microscopy analysis of mitochondria in spinal cord from WT mice, SOD1G93A mice, and SOD1G93A mice treated with P110. Scale bar: 0.2 μm. Data are means ± SD of 20 microscopic fields, at least, from three mice per treatment group. Normal mitochondria structure was dramatically reduced and mitochondria with damaged structure increased in SOD1G93A mice. Percent mitochondria with altered structure were quantified and are represented in the graphs. At least 40 mitochondria were analyzed in each group by an observer blinded to the experimental conditions. For mitochondrial number, mtND2 levels were analyzed by real‐time PCR.Kaplan–Meier survival curve of G93A SOD1 (ALS) mice showing increased survival following P110 treatment (red trace) as compared to the vehicle‐TAT‐treated control ALS mice (black trace).The terminal endpoint was significantly delayed in the P110‐treated ALS mice.Reaching clinical score 3 was significantly delayed in the P110‐treated ALS mice.Kaplan–Meier survival curve of G93A SOD1 (ALS) mice showing increased probability of survival post‐paralysis following P110 treatment (red trace) as compared to the vehicle‐TAT‐treated control ALS mice (black trace).Overall disease progression slowed down significantly, as indicated by increased days from clinical score 1 to terminal endpoint.Spinal cord levels of Drp1, determined in mitochondrial fractions of WT and SOD1‐G93A mice treated with either vehicle‐TAT or with P110 at 3 mg/kg/day by immunoblotting; VDAC was used as a loading control. Protein levels were quantified and represented as fold change of WT (means ± SD).Data information: Mean, standard deviation, and P‐values are shown. (A and G) n = 5 for WT mice; n = 5 for G93A ALS mice + TAT; n = 5 for G93A ALS mice + P110. (B–F) n = 7 for G93A ALS mice + TAT; n = 14 for G93A ALS mice + P110. Probability by (A, C, D, F, G) one‐way ANOVA (with uncorrected Fisher's LSD post hoc test) or (B, E) Log‐rank (Mantel–Cox) test.Source data are available online for this figure.