GDF11 and Anxiety: Next, the elevated plus maze (EPM) test, for anxiety-like phenotype, revealed no difference between aged control and aged GDF11-treated mice in the duration/time spent in open arms (GDF11, 185.5 ± 34.6 s; aged, 139.4 ± 25 s), despite the trend of a subgroup of GDF11-treated mice exceeding the mean duration (Extended Data Fig. 1c).