MMP9 and Parkinson disease: To confirm whether MMP9 is a potential target of Asp G against PD, we evaluated the in vitro effect of Asp G on the gelatinolytic activity of MMP9 in its active and inactive forms based on its gelatinolytic activity by gelatin zymography, which could reflect, to some extent, the effect of Asp G on the potential proteolytic activity of MMP9 as well as the interaction between Asp G and MMP9.