BLUEBERRY JUICE AND ANTHOCYANINS MODULATE OBESITY, LEPTIN AND BETA CELL FUNCTION IN MICE FED A HIGH FAT DIET

Abstract

Consumption of purified blueberry (BB) anthocyanins (ACNs) but not whole BB in the diet has been shown to prevent the development of obesity in mice fed high fat diets (JAFC 56:647, 2008). Our objective was to determine whether BB juice (BBJ) retained the factors responsible for the obesigenic effects of whole BB. Male C57BL/6 mice were assigned to 1 of 6 diet groups: 1) 10% of kcal from fat (LF); 2) a high fat diet [45% kcal from fat (HF45)]; 3) LF diet plus purified ACNs from BBs (0.2 mg total ACNs/mL) in drinking water; 4) HF45 diet plus BB ACNs; 5) LF diet plus BBJ in place of drinking water; 6) HF45 diet plus BBJ. Mice were fed for a total of 72 days. In mice fed the HF45 diet, fat mass as determined by MRI and weights of epididymal and retroperitoneal fat were reduced by 26‐28% (p<0.01) with consumption of purified ACNs and 8‐12% in those consuming BBJ. Serum leptin was increased in mice fed HF45 diet relative to LF control and was decreased to control levels in mice fed blueberry ACNs or BBJ (p<0.003). Pancreatic beta cell function (beta cell Homeostasis Assessment Score) was decreased and serum glucose was increased with HF45 feeding and both returned to normal with HF45 + BB ACNs in the drinking water but not with BBJ. Purified BB ACNs in the drinking water were more effective in preventing obesity in HF45 fed mice compared to BBJ containing an equivalent quantity of ACNs. Supported by: USDA‐NRI Grant 2005‐35503‐15409.