The powerful antioxidant properties of polyphenols in green tea could help protect against the onset of Parkinson's disease, according to new research from Baylor College of Medicine in Houston.
Polyphenols in green tea have already been shown to help protect against cancer and heart disease, and indeed earlier studies had also shown that they might protect against Parkinson's disease. However, this is the first time that the way in which they act to protect against the disease has been shown.
Speaking at the annual meeting of the American Academy of Neurology earlier this week, the study's lead author Tianhong Pan said that Parkinson's disease was characterised by the selective cell death of dopaminergic neurons in the midbrain called substantia nigra and by a marked decrease in dopamine neurotransmitter produced by these neurons.
"We tested the levels of dopamine uptake density in a controlled study of mice and the protective effects on dopaminergic neurons against neurotoxin MPP+-induced injury before and after treatment with polyphenol," said Pan.
"Our results indicate the mechanism, or action, of polyphenol is to inhibit the uptake of dopamine or MPP+ by blocking dopamine transporter (DAT), suggesting that its protective effect in Parkinson's disease is its ability to block the DAT-dependent uptake of environmental neurotoxin."
He stressed that the clinical effects of polyphenols on human Parkinson's disease patients remain to be studied.