Parkinson's disease (PD) is a prevailing
neurodegenerative disorder.
Baicalein has
neuroprotective effects on PD animals, but its mechanism is not clarified. We explored
baicalein effects on PD rats. PD rat models were established by injecting
6-hydroxydopamine into the striatum of substantia nigra on the left side of the rat brain and treated with
baicalein.
Dopamine (DA) content, neuronal apoptosis, neuronal injury, neuronal mitochondria, and autophagy were assessed.
Baicalein-treated PD rats were treated with autophagy inhibitor
3-methyladenine to identify the role of autophagy in PD. PD rats were injected with AgomiR-30b-5p or sh-SIRT1 plasmids and treated with
baicalein. PD rats elicited decreased neurological score and DA secretion of the striatum, increased neuronal apoptosis, and injury, and reduced number of mitochondria and autophagy, whereas
baicalein alleviated neuronal injury and partly recovered
mitochondrial dysfunction,
3-methyladenine inhibited the protection of
baicalein. miR-30b-5p was elevated and
SIRT1 was diminished in PD rats and inhibited by
baicalein. miR-30b-5p targeted
SIRT1. miR-30b-5p overexpression or
SIRT1 silencing annulled the protection of
baicalein. The phosphorylation level of AMPK in the substantia nigra of PD rats was decreased and mTOR was increased, whereas
baicalein annulled these trends. Briefly,
baicalein activated mitochondrial autophagy via miR-30b-5p and the
SIRT1/AMPK/mTOR pathway, thus protecting PD rats.