Chinese Herb Compound Shows Alzheimer's Promise
A common Chinese herb has shown some promise in the fight against Alzheimer’s disease. Here is what scientists have discovered about a compound found in fo-ti, also known as Polygonum multiflorum Thunb.
Can a Chinese herb help Alzheimer’s disease?
When reading about Alzheimer’s disease, some of the terms often bandied about are beta-amyloid, tau, tangles, and plaque. Beta-amyloid (or amyloid-beta) is a protein fragment that accumulates and forms plaque in the brain of people who have Alzheimer’s disease. Tau is another protein that builds up inside cells and causes tangles.
Another protein called alpha-synuclein also accumulates in the brain of Alzheimer’s patients. In the newly published study, researchers reported that overexpression of alpha-synuclein increases with age, noting that the protein builds up in the hippocampus of older mice when compared with normal controls.
The focus of the study was use of a compound called tetrahydroxystilbene glucoside (TSG), which scientists extracted from the Chinese herb fo-ti and administered to mouse models of Alzheimer’s disease. The result of this experiment was a reversal of both the overexpression of alpha-synuclein and accumulation of the protein.
According to the study’s co-lead investigator Lan Zhang, MD, PhD, associate professor, Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Department of Pharmacology of Xuanwu Hospital of Capital Medical University in Beijing, these findings “raise the possibility that TSG might be a novel compound for the treatment of AD and dementia with Lewy body.”
Dementia with Lewy body is the second most common form of progressive dementia after Alzheimer’s. Abnormal round structures called Lewy bodies develop in regions of the brain associated with thinking and movement, resulting in problems with both mental abilities and rigid muscles and tremors.
More about the Chinese herb compound
Fo-ti has been used traditionally as a laxative and a general health tonic. The extract TSG has been the subject of research for several years concerning its effects on cognitive abilities and as a potential natural treatment for Alzheimer’s disease.
In a 2011 study reported in the European Journal of Pharmacology, for example, researchers noted that the fo-ti extract showed an ability to enhance cognitive function in a mouse study. The authors concluded that their data suggested “this effect may contribute to the enhancement of learning and memory.”
Earlier research showed that TSG given to rats significantly improved their learning and memory abilities. This improvement was associated with an increase in the number of synapses in the brain, among other benefits.
Synapses are gaps between cells across which nerve signals are passed, and an increase promotes memory and learning. The authors noted their findings suggested “TSG may be beneficial for the treatment of Alzheimer disease or cognitive impairment in old people.”
This latest study of the effects of TSG on cognitive abilities associated with dementia provides important additional information about this potential treatment for Alzheimer’s disease. More research of this Chinese herb compound is needed to better determine what benefits it may have for individuals with Alzheimer’s and other dementias.
Wang R et al. Changes in hippocampal synapses and learning-memory abilities in age-increasing rats and effects of tetrahydroxystilbene glucoside in aged rats. Neuroscience 2007 Nov 23; 149(4): 739-46
Wang T et al. Tetrahydroxystilbene glucoside, a plant-derived cognitive enhancer, promotes hippocampal synaptic plasticity. European Journal of Pharmacology 2011 Jan 10; 650(1): 206-14
Zhang L et al. Tetrahydroxystilbene glucoside antagonizes age-related a-synuclein overexpression in the hippocampus of APP transgenic mouse model of Alzheimer’s disease. Restorative Neurology & Neuroscience 2013 Jan 1:31(1): 41-52