MAPK8 and depressive symptom measurement: Some studies suggest that impaired monoaminergic neurotransmission contributes to dPD [15, 16], and ZPG may suppress the over-activation of the c-Jun N-terminal protein kinase (JNK) pathway in the substantia nigra, alleviate the inflammatory response in nigral cells, protect the dopaminergic neuron and finally improve depression [17].