GDNF and Parkinson disease: The BDNF/GDNF-related pathway, crucially upregulated by exercise training in various Parkinson’s models, provides neurotrophic support to nigrostriatal dopamine neurons, promoting synaptic plasticity and alleviating motor impairment(Palasz et al., 2019b; Tajiri et al., 2010)—fourteen consecutive days of treadmill training reduced the rotational asymmetry and increased the AMP-activated protein kinase, and BDNF expression of in the striatum of 6-OHDA-induced PD animal models (Rezaee et al., 2020; da Costa et al., 2017).