Figure 5

Effect of the FRα-binding peptide on cognition. (a) Scatter plots show some of the main data from the open field test in mice treated with FRα-binding peptide: time spent by mice in the center square of the box, average speed of movement, and time spent immobile. No changes were found after FRα-binding peptide treatment in anxiety-depression-like behavior (t = 0.7068, df = 15 for center square time), nor in general motor activity (t = 0.7003, df = 16 for speed average and 0.8766, df = 16 for time immobile). The exclusive analysis of female mice has yielded the same results as the data from mixed-sex groups, with no changes observed in any of the OF test parameters (t = 0.7545, df = 9 for center square time; t = 1.512, df = 10 for speed average and t = 1.010, df = 10 for time immobile). (b,c,d) Scatter plots show the results from two memory tests: the novel object recognition (NOR) for short-(2 h) (b) and long-term recognition memory (5 days) (c) and the Y-maze test for spatial memory (d). Mice treated with the peptide showed a significant improvement in memory retention 5 days after the first training session, as shown by memory index of novel object recognition test (t = 1.905, df = 14). Treatment with FRα-binding peptide did not have a significant effect on short-term recognition memory (t = 0.7752, df = 16 in spatial memory test and t = 0.2599, df = 15 in NOR test) but a significant difference was observed in the long-term tests. The exclusive analysis of female mice has yielded the same results as the data from mixed-sex groups, with no changes observed in Y-maze test (t = 0.4131, df = 10) or NOR for short-term recognition memory (t = 0.02451, df = 9), and significant improvement in NOR for long-term recognition memory (P = 0.0132, t = 2.718 and df = 8). Grouped column scatter plot displaying means ± SEM of both the vehicle-treated group and the peptide-treated group are shown. Black plots represent female mice and red square plots represent male mice. All data were analyzed by Student`s t-test. *p < 0.05.