Grape Seed Extract May Reduce Cognitive Decline Associated With Alzheimer's Disease

ScienceDaily (June 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.
Moderate consumption of red wine--approximately one glass for women and two glasses for men, according to the Food and Drug Administration--and its constituent grape compounds has reported health benefits, particularly for cardiovascular function. Pasinetti previously found that red wine reduced cognitive decline in mice genetically modified to develop Alzheimer's disease. In subsequent studies, Pasinetti and colleagues have attempted to isolate which of the nearly 5,000 molecules contained in red wine are important in disease prevention. "Our intent is to develop a highly tolerable, nontoxic, orally available treatment for the prevention and treatment of Alzeheimer's dementia," Pasinetti said.
"The potential of natural compounds to provide real health benefits to brain function is only now beginning to be realized by brain researchers. The lesson they may eventually learn is that sometimes you just can't improve upon Mother nature," said Gary Arendash, PhD, of The Byrd Alzheimer's Institute, an expert unaffiliated with the study.
Chemical analysis showed that the major polyphenol components in the study's grape seed extract product are catechin and epicatechin, which are also abundant in tea and cocoa. These components differ from resveratrol, a polyphenol that has been reported to reduce amyloid beta secretion in cells and generally increase lifespan by mimicking calorie restriction. Resveratrol appears to be effective only at extremely high doses, which may limit its use in people. In contrast, the catechins in the extract product studied appear to be effective at much lower doses.
Karen Hsiao Ashe, MD, PhD, at the University of Minnesota and Minneapolis VA Medical Center, another expert unaffiliated with the study, cautioned that additional research must be completed before these findings translate to a human population. "Unanswered questions pertaining to the polyphenolic extract's use in humans to prevent Alzheimer's disease include: when to start taking it, for how long, how much to take, and most importantly, how does a person know if it is helping to prevent the aggregation of amyloid beta protein in the brain? These questions must be answered before polyphenolics can be recommended as a preventive measure for Alzheimer's disease," Ashe said.
The research was performed at the Center of Excellence for Research in Complementary and Alternative Medicine in Alzheimer's Disease at Mount Sinai School of Medicine and was supported by the National Center for Complementary and Alternative Medicine at the National Institutes of Health, Polyphenolics,the maker of MegaNatural-AZ (the extract studied), the U. S. Department of Veterans Affairs, Japan Human Science Foundation, and the Alzheimer's Association.

New Guidelines Double Amount Of Recommended Vitamin D For Young

The American Academy of Pediatrics (AAP) is doubling the amount of vitamin D it recommends for infants, children and adolescents. The new clinical report, “Prevention of Rickets and Vitamin D Deficiency in Infants, Children, and Adolescents,” recommends all children receive 400 IU a day of vitamin D, beginning in the first few days of life.

The previous recommendation, issued in 2003, called for 200 IU per day beginning in the first two months of life.

The change in recommendation comes after reviewing new clinical trials on vitamin D and the historical precedence of safely giving 400 IU per day to the pediatric population. Clinical data show that 400 units of vitamin D a day will not only prevent rickets, but treat it. This bone-softening disease is preventable with adequate vitamin D, but dietary sources of vitamin D are limited, and it is difficult to determine a safe amount of sunlight exposure to synthesize vitamin D in a given individual. Rickets continues to be reported in the United States in infants and adolescents. The greatest risk for rickets is in exclusively breastfed infants who are not supplemented with 400 IU of vitamin D a day.

Adequate vitamin D throughout childhood may reduce the risk of osteoporosis. In adults, new evidence suggests that vitamin D plays a role in the immune system and may help prevent infections, autoimmune diseases, cancer and diabetes.

“We are doubling the recommended amount of vitamin D children need each day because evidence has shown this could have life-long health benefits,” said Frank Greer, MD, FAAP, chair of the AAP Committee on Nutrition and co-author of the report. “Supplementation is important because most children will not get enough vitamin D through diet alone.”“Breastfeeding is the best source of nutrition for infants. However, because of vitamin D deficiencies in the maternal diet, which affect the vitamin D in a mother’s milk, it is important that breastfed infants receive supplements of vitamin D,” said Carol Wagner, MD, FAAP, member of the AAP Section on Breastfeeding Executive Committee and co-author of the report. “Until it is determined what the vitamin D requirements of the lactating mother-infant dyad are, we must ensure that the breastfeeding infant receives an adequate supply of vitamin D through a supplement of 400 IU per day.”

The new recommendations include:

• Breastfed and partially breastfed infants should be supplemented with 400 IU a day of vitamin D beginning in the first few days of life.
• All non-breastfed infants, as well as older children, who are consuming less than one quart per day of vitamin D-fortified formula or milk, should receive a vitamin D supplement of 400 IU a day.
• Adolescents who do not obtain 400 IU of vitamin D per day through foods should receive a supplement containing that amount.
• Children with increased risk of vitamin D deficiency, such as those taking certain medications, may need higher doses of vitamin D.

Given the growing evidence that adequate vitamin D status during pregnancy is important for fetal development, the AAP also recommends that providers who care for pregnant women consider measuring vitamin D levels in this population.
Adapted from materials provided by American Academy of Pediatrics.
http://www.sciencedaily.com/releases/2008/10/081013141737.htm