Grape Polyphenols May Protect Against Alzheimer's Disease
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NEW YORK, Nov. 7 (UPI) -- New York researchers are focusing on grape polyphenols in wine and grape juice to help maintain long-term cognitive health.
Researchers at the Center for Research in Alternative and Complementary Medicine in Alzheimer�s disease research at Mount Sinai School of Medicine in New York say Concord grape juice and red wine polyphenols show promise in counteracting beta-amyloid plaques associated with cognitive decline.
Two recent population studies associated moderate red wine and 100 percent fruit juice consumption with lowering the risk of Alzheimer�s disease dementia.
"This grape polyphenol research is preliminary, but very encouraging," Dr. Giulio Pasinetti, director of the center and principal investigator of the research program in polyphenolics. "The results show the potential protective role which non-alcoholic, polyphenol-rich Concord grape juice may play in maintaining long term cognitive health."
The research was presented in San Diego at the annual meeting of the Society for Neuroscience.
Thanks for posting this information on grapes. It is very interesting indeed.
Here is a short video that explains the benefit of grapes from a different point of view:
Grape Seed Extract May Reduce Cognitive Decline Associated With Alzheimer's Disease
ScienceDaily (Jun. 18, 2008) — A compound found in grape seed extract reduces plaque formation and resulting cognitive impairment in an animal model of Alzheimer's disease, new research shows.
The study appears in the June 18 issue of The Journal of Neuroscience. Lead study author Giulio Pasinetti, MD, PhD, of Mount Sinai School of Medicine and colleagues found that the grape seed extract prevents amyloid beta accumulation in cells, suggesting that it may block the formation of plaques. In Alzheimer's disease, amyloid beta accumulates to form toxic plaques that disrupt normal brain function.
The researchers tested a grape seed polyphenolic extract product sold as MegaNatural-AZ, made by Polyphenolics, which in part supported the study. Polyphenolic compounds are antioxidants naturally found in wine, tea, chocolate, and some fruits and vegetables. To determine whether the extract could mitigate the effects of Alzheimer's disease, the researchers used mice genetically modified to develop a condition similar to Alzheimer's disease. They exposed pre-symptomatic "Alzheimer's mice" to the extract or placebo daily for five months. The daily dose of the polyphenolic extract was equivalent to the average amount of polyphenolics consumed by a person on a daily basis.
After the five-month period, Alzheimer's mice were at an age at which they normally develop signs of disease. However, the extract exposure reduced amyloid beta accumulation and plaque formation in brains of Alzheimer's mice and also reduced cognitive decline: compared to placebo, extract-exposed Alzheimer's mice showed improved spatial memory.
These data suggest that before symptoms begin, the grape seed extract may prevent or postpone plaque formation and slow cognitive deterioration associated with Alzheimer's disease.
Epidemiological evidence suggests that moderate consumption of red wine reduces the incidence of Alzheimer's disease (AD). To study the protective effects of red wine, experiments recently were executed in the Tg2576 mouse model of AD.
These studies showed that a commercially-available grape seed polyphenolic extract, MegaNatural-AZ (MN), significantly attenuated AD-type cognitive deterioration and reduced cerebral amyloid deposition (Wang, J., Ho, L., Zhao, W., Ono, K., Rosensweig, C., Chen, L., Humala, N., Teplow, D.B., and Pasinetti, G.M. (2008) J. Neurosci. 28, 6388-6392).
To elucidate the mechanistic bases for these observations, here we used circular dichroism spectroscopy (CD), photo-induced cross-linking of unmodified proteins (PICUP), thioflavin T fluorescence (ThT), size exclusion chromatography (SEC), and electron microscopy (EM) to examine the effects of MN on the assembly of the two predominant disease-related amyloid beta-protein alloforms, Abeta40 and Abeta42. We also examined the effects of MN on Abeta-induced cytotoxicity by assaying 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) metabolism and lactate dehydrogenase (LDH) activity in Abeta-treated, differentiated pheochromocytoma (PC12) cells.
Initial studies revealed that MN blocked Abeta fibril formation. Subsequent evaluation of the assembly-stage specificity of the effect showed that MN was able to inhibit protofibril formation, pre-protofibrillar oligomerization, and initial coil-alpha-helix/beta-sheet secondary structure transitions.
Importantly, MN had protective effects in assays of cytotoxicity in which MN was mixed with Abeta prior to peptide assembly or following assembly and just prior to peptide addition to cells. These data suggest that MN is worthy of consideration as a therapeutic agent for AD.
Another more up-to-date article about polyphenols preventing beta-amyloid and Alzheimer's Disease.
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Regular intake of polyphenols elevates brain levels
An article appearing online in advance of the publication of the September, 2009 issue of the Journal of Alzheimer's Disease revealed that regular intake of grape seed polyphenols effectively elevates plasma and brain levels of the compounds. Polyphenols are believed to protect against the formation of beta-amyloid, a toxic protein that forms in the brains of Alzheimer's disease patients which may be responsible for some the disease's damaging effects. Earlier research had found that little, if any, polyphenols reached the brain following ingestion; however, these experiments evaluated polyphenol levels following single or sporadic dosing.
Purdue University associate professor of food science Mario Ferruzzi, in collaboration with Giulio Pasinetti, MD of Mount Sinai School of Medicine, administered three different doses of a grape seed polyphenol extract to rats by intragastric gavage. The polyphenols gallic acid, catechin and epicatechin, and their metabolites were found in plasma in dose-dependent levels after one dose of the extract. Plasma levels measured after ten days of continual ingestion doubled in comparison with levels measured after just one polyphenol dose. Importantly, although epicatechin and catechin were not detectable in the brains of the animals after one dose, they reached significant levels following ten days of administration. "This shows that reasonable and chronic consumption of these products may be the way to go, rather than single, high doses, similar to drugs," Dr Ferruzzi explained. "It's like eating an apple a day, not a case of apples over two days every month."
"The most important thing is that when we follow the repetitive administration of this compound, we were able to observe the transfer of the compound to the brain," noted Dr Pasinetti, who is the Aidekman Family Professor in Neurology and director of the Center of Excellence for Novel Approaches to Neurotherapeutics. "This may help us figure out the proper concentration necessary to get these chemicals to the brain."
Dr Ferruzzi observed that their discovery may be relevant to the delivery of other compounds and drugs. "It could become important in terms of side effects," Ferruzzi said. "You could be overdosing because the body is adapting and absorbing or metabolizing these compounds differently over time."
He added that future research will seek to determine the mechanisms that govern the absorption of compounds during chronic consumption.
Grape Polyphenols May Protect Against Alzheimer's Disease
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