SIRT5 and Parkinsonism: However, more recent studies have found counter evidence showing that SIRT5 depletion causes mitochondrial dysfunction, expression does not increase with Alzheimer’s progression, and can only be linked to Parkinson’s via an autophagic degradation of SIRT5 itself (Baeken et al., 2021; Haschler et al., 2021; Wu et al., 2021).