Fig. 2

Possible mechanisms for neuroprotective function of exercise and differences between sexes. DDIT4, a gene which is associated with promotion of neuroal atrophy and blocks mTOR signaling pathway to neural plasticity, was down-regulated through exercise, more so in men than in women (in luteal phase). Conversely, KMO, a pivotal enzyme of the kynurenine pathway of tryptophan metabolism, associated with induction of depression, was down-regulated in women only. Growth factors VEGFA, IGF1R, and IGF2R were also induced by exercise with minor differences between sexes. Finally, FGD4 mRNA, a myelination inducing gene, was significantly enhanced by exercise in both sexes with men showing more pronounced regulation. Overall, the observed gene expression regulations may be interpretable as neuroprotective effects of exercise