Disclaimer: Scientific studies are for informational and educational purpose only. French Glory Isotonic OPC products are nutritional supplements, not intended to diagnose, treat, care for or prevent any diseases


Alzheimer's disease may develop to some people in the ageing process, as a consequence of deterioration in cognitive function. The early signs for ageing include our weaker and weaker ability to learn and form thoughts.

Several research groups at UCLA, Purdue University, University of Minnesota, Mount Sinai School of Medicine, etc. have been actively investigating the effects of grape seed extract natural products on cognitive function, so that grape seed extract may act as therapeutic agents to prevent or slow down  Alzheimer's disease.

Several studies have been published showing grape seed extract natural products reduce plaque formation and prevent cognitive impairment using animal models of Alzheimer's disease. Grape seed extract prevents amyloid beta accumulation in cells, suggesting suppress the formation of plaques. In Alzheimer's disease, amyloid beta accumulates to form toxic plaques that disrupt normal brain function.


Pubished Articles and Summaries

1. Asha Devi S, et al. Grape seed proanthocyanidin lowers brain oxidative stress in adult and middle-aged rats. Exp Gerontol. 2011 Nov;46(11):958-64.

Abstract

There is growing concern over the increasing instances of decline in cognitive abilities with aging in humans. The present study evaluated the benefits of the natural antioxidant, grape seed proanthocyanidin extract (GSPE) in treating the effects of age-related oxidative stress (OS) and accumulation of lipofuscin (LF) on the cognitive ability in rats. Female Wistar rats of 3- and 12-months of age received a daily oral supplement of GSPE until they attained 6- and 15-months of age. During this period, rats were tested for their cognitive ability. At the end of this period, blood glucose and markers of OS were assessed in the hippocampus. GSPE lowered blood glucose, lipid peroxidation, hydrogen peroxide level, and increased protein sulphydryl (P-SH) content in the hippocampus. In addition, GSPE significantly improved cognitive performance in the two age groups. These results demonstrate that the extent of OS-related LF accumulation is reducible by GSPE. They also suggest a critical role for GSPE as a neuroprotectant in the hippocampus and in preventing cognitive loss with aging.


2. Liu P, Kemper LJ, Wang J, Zahs KR, Ashe KH, Pasinetti GM. Grape seed polyphenolic extract specifically decreases aβ*56 in the brains of Tg2576 mice. J Alzheimers Dis. 2011;26(4):657-66.

N. Bud Grossman Center for Memory Research and Care, University of Minnesota Medical School, Minneapolis, MN, USA.

Abstract

Amyloid-β (Aβ) oligomers, found in the brains of Alzheimer's disease (AD) patients and transgenic mouse models of AD, cause synaptotoxicity and memory impairment. Grape seed polyphenolic extract (GSPE) inhibits Aβ oligomerization in vitro and attenuates cognitive impairment and AD-related neuropathology in the brains of transgenic mice. In the current study, GSPE was administered to Tg2576 mice for a period of five months. Treatment significantly decreased brain levels of Aβ*56, a 56-kDa Aβ oligomer previously shown to induce memory dysfunction in rodents, without changing the levels of transgenic amyloid-β protein precursor, monomeric Aβ, or other Aβ oligomers. These results thus provide the first demonstration that a safe and affordable intervention can lower the levels of a memory-impairing Aβ oligomer in vivo and strongly suggest that GSPE should be further tested as a potential prevention and/or therapy for AD.



3. Ferruzzi MG, Lobo JK, et al. Bioavailability of gallic acid and catechins from grape seed polyphenol extract is improved by repeated dosing in rats: implications for treatment in Alzheimer's disease. J Alzheimers Dis. 2009;18(1):113-24.

Department of Food Science, Purdue University, West Lafayette, IN 47907, USA. mferruzz@purdue.edu

Abstract

The present study explored the bioavailability and brain deposition of a grape seed polyphenolic extract (GSPE) previously found to attenuate cognitive deterioration in a mouse model of Alzheimer's disease (AD). Plasma pharmacokinetic response of major GSPE phenolic components was measured following intragastric gavage of 50, 100, and 150 mg GSPE per kg body weight. Liquid chromatography-mass spectrometry (LC-MS) analysis identified gallic acid (GA), catechin (C), and epicatechin (EC) in plasma of rats gavaged acutely with GSPE. Additionally, 4-methylgallic acid (4-OMeGA), 3'-methylcatechin (3'-OMeC), and 3'-methylepicatechin (3'-OMeEC) were identified as circulating metabolites of GSPE phenolic constituents. Cmax for individual GSPE constituents and their metabolites increased in a dose-dependent fashion (with increasing GSPE oral dose). Repeated daily exposure to GSPE was found to significantly increase bioavailability (defined as plasma AUC0-8h) of GA, C, and EC by 198, 253, and 282% relative to animals receiving only a single acute GSPE dose. EC and C were not detectable in brain tissues of rats receiving a single GSPE dose but reached levels of 290.7 +/-45.9 and 576.7 +/- 227.7 pg/g in brain tissues from rats administered GSPE for 10 days. This study suggests that brain deposition of GA, C, and EC is affected by repeated dosing of GSPE.


4. Ho L, Yemul S, Wang J, Pasinetti GM. Grape seed polyphenolic extract as a potential novel therapeutic agent in tauopathies. J Alzheimers Dis. 2009;16(2):433-9.

Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029, USA.

Abstract

Abnormal misfoldings of the microtubule-associated protein tau, leading to the aggregation of tau into paired helical filaments that are ultimately deposited as neurofibrillary tangles, is a key neuropathologic feature of a number of neurodegenerative disorders collectively referred to as tauopathies. We recently observed that a particular grape seed polyphenolic extract (GSPE), namely, Meganatural-Az may attenuate the generation and stability of misfolded proteins. We hypothesized that Meganatural-Az GSPE might also attenuate tau protein misfolding that leads to the generation of tau filamentary aggregates that are critical for the initiation and progression of neurodegeneration and/or cognitive dysfunctions in tauopathies. In this study, we used in vitro aggregations of synthetic Ac(306)VQIVYK(311) tau peptide as a model system to explore whether Meganatural-Az GSPE might modulate aggregations of tau protein. We demonstrate that this GSPE is capable of inhibiting tau peptide aggregations, as well as dissociating preformed tau peptide aggregates. Results from this study suggest that this GSPE might provide beneficial disease-modifying bioactivities in tau-associated neurodegenerative disorders by modulating tau-mediated neuropathologic mechanisms. Our observation, in conjunction with the demonstrated bioavailability, as well as safety and tolerability, of this GSPE, supports the development of Meganatural-Az GSPE for the prevention and/or treatment of tau-associated neurodegenerative disorders.


5. Ono K, Condron MM, Ho L, et al. Effects of grape seed-derived polyphenols on amyloid beta-protein self-assembly and cytotoxicity. J Biol Chem. 2008 Nov 21;283(47):32176-87.

Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7334, USA.

Abstract

Epidemiological evidence suggests that moderate consumption of red wine reduces the incidence of Alzheimer 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 CD spectroscopy, photo-induced cross-linking of unmodified proteins, thioflavin T fluorescence, size exclusion chromatography, and electron microscopy 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 metabolism and lactate dehydrogenase 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.


6. Wang J, Ho L, Zhao W, Ono K, Rosensweig C, et al. Grape-derived polyphenolics prevent Abeta oligomerization and attenuate cognitive deterioration in a mouse model of Alzheimer's disease. J Neurosci. 2008 Jun 18;28(25):6388-92.

Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, USA.

Abstract

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive impairments in memory and cognition. Extracellular accumulation of soluble high-molecular-weight (HMW) Abeta oligomers has been proposed to be largely responsible for AD dementia and memory deficits in the Tg2576 mice, a model of AD. In this study, we found that a naturally derived grape seed polyphenolic extract can significantly inhibit amyloid beta-protein aggregation into high-molecular-weight oligomers in vitro. When orally administered to Tg2576 mice, this polyphenolic preparation significantly attenuates AD-type cognitive deterioration coincidentally with reduced HMW soluble oligomeric Abeta in the brain. Our study suggests that grape seed-derived polyphenolics may be useful agents to prevent or treat AD.




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Grape Seed Extract Are Investigated for Cognitive Function and Alzheimer's Disease