Tetramethylpyrazine alleviated cytokine synthesis and dopamine deficit and improved motor dysfunction in the mice model of Parkinson's disease

It was previously reported that cytokines and neurotoxins released from activated inflammatory cells induced the loss of projecting dopaminergic neurons in the substantia nigra, which triggered the pathogenesis of PD. The present study investigated the effect of treatment with tetramethylpyrazine (TMP) on the central cytokine synthesis, striatal dopamine content and glutamatergic transmission, and behavioral performance in the rotarod task in mice injected with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Treatment with TMP significantly improved the behavioral performance in the rotarod task in mice injected with MPTP. It also decreased the upregulation of cytokines (tumor necrosis factor-α and interleukin-1β) in the substantia nigra and striatum in these modeled mice. Furthermore, treatment with TMP significantly improved the dopamine deficits and attenuated the upregulation of striatal basal glutamatergic strength in the striatum of mice injected with MPTP. These results indicated that TMP might serve as a novel approach for the treatment of patients with PD.