Current PD treatment primarily consists of DA replacement therapies, such as levodopa, DA agonists, and inhibitors of catechol-O-methyl transferase and monoamine oxidase (MAO) B. Additionally, anticholinergics and amantadine are used to ameliorate motor symptoms, while antipsychotics and antidepressants are prescribed to treat non-motor symptoms of PD [43,44]. Here, MAOB is linked to Parkinson disease.