fig1

Figure 1. Both favorable and unfavorable activated microglia participate in the pathophysiology of PD. Unfavorable microglia present in the SNc release neurotoxic proinflammatory mediators while accelerating the degeneration of DA neurons. Favorable microglia present in the SNr and GPi engage in eliminating hyperactive glutamatergic synapses from the STN in the indirect pathway of the basal ganglia. This figure is based primarily on the study by Aono et al.^[47]. PD: Parkinson’s disease; SNc: substantia nigra pars compacta; DA: dopaminergic; SNr: substantia nigra pars reticulata; GPi: globus pallidus; STN: subthalamic nuclei; GPe: globus pallidus pars externa