Fig. 2

Effects of sex, APOE genotype, and metformin on anxiety-like states in aged mice. (A, B) The time spent in the open arms (A) and open arms entries (B) for the elevated plus maze (EPM) of the 18-month-old male and female apoE-TR mice treated with normal saline (NS) and metformin (Met). (C) Speed for the EPM. (D, E) The time spent (D) and distance traveled (E) in the central area for the open field test (OFT) of the 18-month-old male and female apoE-TR mice treated with normal saline (NS) and metformin (Met). (F) Speed for the OFT. n = 12–15/ group. Data are presented as mean ± SEM. Three-way ANOVA was used to calculate statistical significance. * P < 0.05, ** P < 0.01 for male vs. female, # P < 0.05 for apoE3 vs. apoE4, $ P < 0.05, $$ P < 0.01 for normal saline vs. metformin