MMP3 and Parkinson disease: These behavioral effects of MMP-3 deletion on the lesioned nigrostriatal DA system, together with the knowledge that the genetic ablation of MMP-3 prevents microglial activation, infiltration of T leukocyte, and BBB disruption, suggest that MMP-3 could be a useful therapeutic target for treating PD and other neurodegenerative disorders involving neuroinflammation and compromised BBB integrity.