Location: Diet, Genomics and Immunology LaboratoryTitle: An extract of chokeberry attenuates weight gain and modulates multiple signaling pathways in epididymal adipose tissue of rats fed a fructose-rich diet Author
Submitted to: British Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/2/2011
Publication Date: 12/6/2011
Citation: Anderson, R.A., Qin, B. 2011. An extract of chokeberry attenuates weight gain and modulates multiple signaling pathways in epididymal adipose tissue of rats fed a fructose-rich diet. British Journal of Nutrition. 108:581-587. Interpretive Summary: More than 60% of the U.S. population has potential problems associated with the metabolic syndrome and/or obesity. The most recognizable sign of the metabolic syndrome is a waist circumference larger than 35 inches for women and 40 inches for men. Chokeberries, which are berries found in the eastern part of the U.S., are a rich source of anthocyanins which may contribute to the prevention of obesity and the metabolic syndrome. The aim of this study was to determine if an extract from chokeberries inhibits weight gain in rats fed a high fructose diet and to explore the potential mechanisms related to insulin signaling, fat metabolism, and inflammation. Chokeberry extract consumption lowered body weight gain, epididymal fat, blood glucose, triglycerides, and cholesterol in the rats studied. Chokeberry extract also led to beneficial effects on insulin function and decreases in factors associated with inflammation. In summary, these results suggest that the consumption of chokeberries may inhibit weight gain and decrease risk factors related to insulin resistance, fat metabolism and inflammation. This study will be of benefit to scientists working on the mechanisms involved in the onset of diseases related to the metabolic syndrome and obesity and potentially to the millions of people with, or who may go on to develop, chronic diseases associated with obesity and the metabolic syndrome, including type 2 diabetes and cardiovascular diseases.
Technical Abstract: Chokeberries are a rich source of anthocyanins, which may contribute to the prevention of obesity and metabolic syndrome. The aim of this study was to determine if an extract from chokeberries would reduce weight gain in rats fed a fructose-rich diet, and to explore the potential mechanisms related to insulin signaling, adipogenesis, and inflammatory-related pathways. Chokeberry extract (100 and 200 mg/kg body weight daily) was added to the drinking water for 6 wks in rats fed a high fructose diet to induce insulin resistance. Chokeberry extract consumption lowered epididymal fat, blood glucose, triglycerides, cholesterol, and LDL-cholesterol. Chokeberry extract consumption also elevated plasma adiponectin levels and inhibited plasma TNF-alpha and IL6. There were increases in the mRNA expression for Irs 1 & 2, Pi3k, Glut1 & 4, and Gys1, and decreases in mRNA levels of Gsk3ß. The protein and gene expression of adiponectin and Ppar-gamma levels were up-regulated and Fabp4, Fas, and Lpl mRNA levels were inhibited in epididymal adipose tissue of chokeberry extract-treated rats. The levels of adipocyte gene expression of inflammatory factors, such as Il1b, Il6, and Tnf-alpha, were lowered, and protein and gene expression of ZFP36 were enhanced by the intake of the chokeberry extract. In summary, these results suggest that the chokeberry extract decreased risk factors related to insulin resistance by modulating multiple genes associated with insulin signaling, adipogenesis, and inflammation.