Moderate
physical exercise acts at molecular and behavioural levels, such as interfering in
neuroplasticity,
cell death,
neurogenesis,
cognition and motor functions. Therefore, the aim of this study is to analyse the cellular effects of moderate treadmill
running upon
substantia nigra during early neurodegeneration.
Aged male Lewis
rats (9-month-old) were exposed to
rotenone 1mg/kg/day (8weeks) and 6weeks of moderate treadmill
running, beginning 4weeks after
rotenone exposure.
Substantia nigra was extracted and submitted to
proteasome and
antioxidant enzymes activities,
hydrogen peroxide levels and
Western blot to evaluate
tyrosine hydroxylase (TH),
alpha-synuclein, Tom-20, PINK1, TrkB, SLP1, CRMP-2, Rab-27b, LC3II and
Beclin-1 level. It was demonstrated that moderate treadmill
running, practiced during early neurodegeneration, prevented the increase of
alpha-synuclein and maintained the levels of TH unaltered in
substantia nigra of
aged rats.
Physical exercise also stimulated
autophagy and prevented impairment of
mitophagy, but decreased
proteasome activity in
rotenone-exposed
aged rats.
Physical activity also prevented H2O2 increase during early neurodegeneration, although the involved mechanism remains to be elucidated. TrkB levels and its anterograde trafficking seem not to be influenced by moderate treadmill
running. In conclusion, moderate physical
training could prevent early neurodegeneration in
substantia nigra through the improvement of
autophagy and
mitophagy.