GPR35 and Parkinson disease: It investigated the impact of Gpr35 deficiency on motor function, neuroinflammation, and dopaminergic neurodegeneration, using the Gpr35 knockout (Gpr35−/−) and wild-type (WT) mice in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD model, and Gpr35 up-/down-regulation on reverse neuroinflammation, oxidative stress, and neuronal apoptosis using Gpr35 agonist kynurenic acid (KYNA) and small interfering RNA in microglial and dopaminergic cell models.