PINK1 and Parkinson disease: Interestingly, others have found inhibition of Drp1 improves mitochondrial fission by upregulating PINK1/Parkin, increases in tyrosine hydroxylase (TH) expression in the substantia nigra and striatum, normalizes mitochondrial ultrastructure and fission function, ameliorates part of motor function in MPTP-induced PD mice (Feng et al., 2021).