Resveratrol Helps The Heart Says New University Study
Resveratrol Keeps Hearts Young
June 4, 2008
Resveratrol, A natural compound found in red wine, may protect the heart against the effects of the aging process, researchers said on Tuesday.
In their study, mice were given a diet supplemented with the compound known as resveratrol starting at their equivalent of middle age until old age. These mice experienced changes in their gene activity related to aging in a way very similar to mice that were placed on a so-called calorie restriction diet that slows the aging process by greatly cutting dietary energy intake. Most striking was how the resveratrol, like calorie restriction, blocked the decline in heart function typically associated with aging, according to Tomas Prolla, a University of Wisconsin professor of genetics who helped lead the study. Much as Spaniard Juan Ponce de Leon once searched for the mythical fountain of youth, researchers now are seeking ways to extend the quality and length of human life. In some studies, animals given a diet with greatly reduced caloric intake have lived longer than animals with normal diets. But perpetual hunger is a steep price to pay for greater longevity, some researchers say. Resveratrol, found in abundance in grapes and in red wine, has drawn a lot of interest from scientists and some companies, including GlaxoSmithKline, which in April said it would pay $720 million to buy Sirtris Pharmaceuticals Inc, a company that is developing drugs that mimic the effects of resveratrol. Some studies have shown that in high doses, resveratrol extended the life span of fruit flies and worms and prevented early death in mice fed a high-fat diet. In this study, mice were given relatively low doses compared to the earlier research, and still experienced important aging-related benefits, the researchers said. The researchers began giving the resveratrol diet to the mice when they were 14 months old — their middle age — and followed the animals until they were about 30 months old. The researchers then conducted tests on cardiac function and on gene activity related to aging. “”Resveratrol at low doses can retard some aspects of the aging process, including heart aging, and it may do so by mimicking some of the effects of caloric restriction, which is known to retard aging in several tissues and extend life span,”" added Prolla, whose study was published in the scientific journal PLoS ONE. Using a method that permits simultaneous analysis of thousands of genes at the same time, the researchers found a huge overlap in the genes whose activity were changed by resveratrol and caloric restriction. They looked at the heart, brain and muscles, and said that the effect of resveratrol was strongest in the heart but did prevent some aging-related changes in the other tissues. Just because mice had these benefits does not mean people also would, although Prolla said, “”I think there’s a high likelihood that our findings are applicable to humans.”" He said he expected to see a lot of studies in the coming years on the effects of resveratrol supplementation in people.
Zinc
Zinc helps children thinkApril 10, 2005 Eleven-year-olds that took zinc supplements for five days each week had better mental performance after three months than their classmates, said researchers yesterday.
The children taking an extra 20mg of zinc responded more quickly and accurately on memory tasks and with more sustained attention than classmates who did not take the mineral.
Beneficial effects were seen regardless of the youngsters’ previous zinc status, said the researchers led by Dr James Penland from the US Agricultural Research Service’s Grand Forks Human Nutrition Research Center in North Dakota.
The findings, presented at the Experimental Biology meeting this week, suggest that there could be new demand for fortified foods and supplements for this age group.
Although zinc nutrition has been related to motor, cognitive and psychosocial function in very young children and adults, this is the first study of its effect in adolescents.
Zinc deficiency is not uncommon, even in nations such as the United States, and the risk is particularly high in adolescents, said Dr Penland, because they are undergoing rapid growth and often have poor eating habits. They may not consume enough zinc-rich foods like red meat, fish and grains.
Moreover the current recommended daily allowance is only 15mg for adults in the US, and up to 9.5 mg a day for men and 4-7 mg a day for women in the UK.
In the study, 111 girls and 98 boys consumed four ounces of fruit juice containing either 0, 10 or 20 mg of zinc gluconate each school day for 10 to 12 weeks. Students, their parents and teachers did not know who was receiving which, if any, zinc supplementation.
At the beginning and end of the study, students performed a battery of tasks designed to measure mental and motor skills, like attention, memory, problem-solving and hand-eye coordination.
Students, their parents, and teachers filled out questionnaires about the students’ mental, physical and social abilities and skills, school performance, and problems in any of these areas to provide a measure of psychosocial function.
Blood samples measured zinc status before and after the treatment.
Compared to the students who received no additional zinc, students who consumed an additional 20 mg zinc each day decreased reaction time on a visual memory task by 12 per cent versus 6 per cent; increased correct answers on a word recognition task by 9 per cent versus 3 per cent; and increased scores on a task requiring sustained attention and vigilance by 6 per cent versus 1 per cent.
Those who received only 10 mg a day, the US Recommended Dietary Allowances (RDA) for this age group, did not significantly improve performance, however.
Supplementation at either the 10 mg or 20 mg did not appear to improve motor and social skills, although girls receiving the placebo experienced a 10 per cent increase in conduct problems during the study while the behaviour of girls receiving any level of zinc supplementation remained unchanged, reported the researchers.
Previous studies have shown that zinc is needed for growth and immune function and may be important for eye-hand coordination and reasoning in very young children. It also appears to influence memory, muscle strength and endurance in adults.