Grape-soy team-up enhances health benefits, says study
the anti-obesity effects of the individual compounds, reports new
research from the University of Georgia.
The study used human 3T3-L1 cells to model the development and biochemistry of fat cells, and found that combining the compounds reduced fat cell numbers by 59 and 70 per cent more than genistein and resveratrol alone, respectively. The research is published in the Journal of Nutrition. "These results indicate that genistein and resveratrol in combination produce enhanced effects on inhibiting adipogenesis (formation of fat cells)," wrote the authors, led by Srujana Rayalam. "Thus, the combination of genistein and resveratrol is more potent in exerting anti-obesity effects than the individual compounds," they added. Rayalam and co-workers exposed pre-adipocytes and mature adipocytes to 50 and 100 micromole per litre doses of genistein and resveratrol individually or in combination. They report that both compounds reduced cell viability in both cell types in a dose-dependent manner. In addition to enhanced inhibition of the cells by the combination of genistein and resveratrol, compared to the individual compounds, the teaming up of the compounds induced apoptosis (programmed cell death) of the fat cells by 242 per cent, compared to control. The individual compounds at their highest dose both increased apoptosis by only 46 per cent. The researchers also report that, at a dose of 25 micromoles per litre, the individual compounds reduced the accumulation of lipids by 30 and 20 per cent, respectively. In combination at the same respective doses, lipid accumulation was decreased by 77.9 per cent, they said. A mechanistic study was performed by Rayalam and co-workers to explain the observations. They report that the combination of genistein and resveratrol produced a down-regulation of specific proteins associated with the development of fat cells, most notably the adipocyte-specific protein PPAR. PPAR-gamma is a hormone receptor which reportedly plays a key role in the control of expression and differentiation of adipocyte genes. No such effects were observed for the individual compounds. Previous studies have linked resveratrol to having a positive effect on extending survival rates of mice and preventing the negative effects of high-calorie diets. It has also been linked to diabetes, heart health and obesity. Resveratrol - an antioxidant - is also found in raspberries, peanuts and blueberries, which in turn fall under the umbrella group of superfoods. In red wine, the amount of resveratrol in a bottle can vary between types of grapes and growing seasons, and can vary between 0.2 and 5.8 milligrams per litre. But nearly all dark red wines - merlot, cabernet, zinfandel, shiraz and pinot noir - contain resveratrol. Source: Journal of Nutrition December 2007, Volume 137, Pages 2668-2673 "Resveratrol Potentiates Genistein's Antiadipogenic and Proapoptotic Effects in 3T3-L1 Adipocytes" Authors: Srujana Rayalam, M.A. Della-Fera, J.-Y. Yang, H.J. Park, S. Ambati and C.A. Baile