Potential neuroprotective activity of Ginseng in Parkinson's disease: a review

Parkinson's disease is a chronic, multifactorial and progressive neurologic condition that affects around six million people worldwide, normally over 60 years of age, and is characterized by neurodegeneration of dopaminergic neurons in the substantia nigra. The species of the genus Panax, popularly named as "Ginseng", are widely used as herbal remedies for their multiple beneficial effects, including their neurotherapeutic efficacies as protectors against major neurodegenerative diseases. The current review aims to report major findings and current knowledge on Ginseng and its major constituents as potential neuroprotective agents against Parkinson's disease, focusing on its mechanisms of action and molecular targets. For that purpose, it includes all research works published in MEDLINE/PubMed within the last decade by utilizing the following combination of the keywords: "Ginseng, ginsenosides, neuroprotection and Parkinson's disease". As reported, most of the studies have been carried out on isolated compounds rather than extracts. The major ginsenosides investigated as neuroprotector agents for Parkinson's disease are Rb1, Rg1, Rd and Re. Other minor components such as Notoginsenoside R2 and Pseudoginsenoside-F11 have also attracted remarkable interest as promising antiparkinson agents. These compounds exert their neuroprotective activity through different mechanisms including, among Others, inhibition of oxidative stress and neuroinflammation, decrease in toxins-induced Apoptosis and nigral iron levels, and regulation of N-methyl-D-aspartate receptor channel activity.