Fig. 2: A s.c. injection of PMP1 enhances memory in WT mice and reverses memory and motor deficits in AS mice; dose response curves.

Dose-response curves of a single s.c. injection of PMP1 on (A) nOR in WT mice, B nOR on AS mice, and (C) hindlimb clasping in AS mice. Experimental timeline is shown above graphs. A, B: after habituation (hab) to the arena, mice received a s.c. injection of a dose of PMP1 (283 μg/kg, 850 μg/kg, 2550 μg/kg) or vehicle (veh) 20 min before nOR training and were longitudinally tested for memory retention 4, 24 h, 1, 2, 3, and 4 weeks after training. From left to right, graphs show: total time spent exploring both objects during training expressed in seconds (s), percent of time spent exploring the new object (% preference) during the test session at 4h, 24 h, 1, 2, 3, and 4 weeks after training. N = 6–9 per group for WT mice and n = 8–9 per group for AS mice; each, 2 independent experiments). Dots represent the percent of preference of each mouse (blue dots are for males, and pink dots are for females). Data are expressed as mean ± s.e.m; one-way ANOVA followed by Tukey’s post-hoc test was used. *p < 0.05, **p < 0.01, ***p < 0.001. C Mice received a s.c. injection of a dose of PMP1 (283, 850, 2550 μg/kg) or veh 20 min before testing their hindlimb clasping behavior. The hindlimb clasping behavior was tested longitudinally at 20 min, 4h, 24 h, 1, 2, 3, and 4 weeks after the injection. N = 8–9 per group; 2 independent experiments. Dots represent the clasping score for each mouse (blue dots are for males, and pink dots are for females). Data are expressed as mean ± s.e.m. relative to clasping score and one-way ANOVA followed by Tukey’s post-hoc test; *p < 0.05, ***p < 0.001. The red bars show significant inter-group comparisons between non-vehicle groups.