Effect and Mechanism of Chinese Herbal Medicine on Parkinson's Disease.

Parkinson's disease is a progressive neurodegenerative disorder. Although both genetic and environmental factors are implicated in the development of Parkinson's disease, the cause of the disease is still unclear. So far conventional treatments to Parkinson's are symptomatic relief and focused mainly on motor symptoms. Chinese herbal medicine has been used to treat many conditions in China, Korea, Japan, and many Southeast Asian countries for 1000 years. During past a few decades, Chinese herbal medicine has gained wider and increasing acceptance within both public and medical profession due to its effectiveness on many conditions in western countries. In this chapter, mechanisms of action of many Chinese herbal compounds/extracts and Chinese herb formulas on the models of Parkinson's were reviewed. Further, reports of effectiveness of Chinese herb formulas on patients with Parkinson's were summarized. It was shown that both Chinese herbal compounds/extracts and herb formulas have either specific target mechanisms of action or multitargets mechanisms of action, as antioxidant, antiinflammatory, and antiapoptosis agents. Clinical studies showed that Chinese herb formulas as an adjunct improved both motor and nonmotor symptoms, and reduced dose of dopaminergic drugs and occurrence of dyskinesia. The evidence from the studies suggests that Chinese herb medicine has potential, acting as neuroprotective to slow down the progression of Parkinson's, and it is able to simultaneously treat both motor and nonmotor symptoms of Parkinson's. More studies are needed to explore the new compounds/extracts derived from Chinese herbs, in particular, their mechanisms of action. It is hopeful that new drugs developed from Chinese herb compounds/extracts and Chinese herb formulas will lead to better and complimentary therapy to PD.