DHT improves motor performances and survival in SOD1 mice.

A: SOD1 mice were implanted with either a DHT-filled or an empty silastic (control) tube at P75, and their motor performances were assessed every 5 days by the rota-rod test. A mouse was placed on the rotating rod at 11 rpm, and the latency until the mouse fell from the rotating rod was recorded in seconds. DHT-treated SOD1 mice (filled square, n = 16) stayed longer on the rotating rod compared with control SOD1 mice (empty circle, n = 22). Data are mean ± SEM. p = 0.043 (2-way ANOVA). B: Hindlimbs were placed into non-toxic paints and a mouse was allowed to walk on a 50 cm- length of paper, and its continuous locomotion was recorded. Representative footprints obtained from DHT-implanted or empty tube-implanted SOD1 mice at P100 are shown. DHT-treated SOD1 mouse (top panel) showed a longer step length without a trace of dragging hindlimb compared with control SOD1 mice (bottom panel). C: Step length was quantified by dividing walking distance by the number of the steps taken within the measured walking distance. DHT-treated SOD1 mice (filled square, n = 6) showed longer step length compared with control SOD1 mice (empty circle, n = 7). p = 0.003 (paired t-test). D: DHT-treated SOD1 mice showed significantly increased survival duration after DHT administration by 11% in DHT-treated SOD1-G93A mice (82.9±2.9 days, n = 18) compared with age-matched control SOD1-G93A mice (74.8±2.2 days, n = 24). E: DHT-treated SOD1 mice showed significantly increased the overall lifespan by 8 days (filled square, 157.9±2.9 days, n = 18) compared with control SOD1 mice (empty circle, 149.8±2.2 days, n = 24). p = 0.0174 (log-rank test).