Phytochemicals Added To The Feed Of Ovariectomized Adult Rats Increase Brown Adipose Activity

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 702-709-Obesity: Response to Interventions
Basic
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-707
Colette N Miller*1, Suresh Ambati1, Erica Bass1, Natalie N Hohos1, Diane L Hartzell2, Mary Anne Della-Fera1, Srujana Rayalam3 and Clifton A Baile2
1University of Georgia, Athens, GA, 2Univ of Georgia, Athens, GA, 3Philadelphia College of Osteopat, Suwanee, GA
Brown adipose tissue (BAT) is a unique adipose cell type that uncouples respiration and dissipates heat using lipids as an energy source, and thus is highly metabolically active. A reduction in BAT is a commonly observed characteristic in obese rodent models and in humans. As an increase in BAT activity has been positively associated with protection against adiposity, compounds that can induce BAT activation may help with preventing weight gain and may even promote weight loss. Phytochemicals like resveratrol (R) have shown the capacity to induce BAT activity through upregulation of common BAT genes including UCP1 and PGC-1 alpha in both cellular and rodent models. While a positive relationship exists between R and BAT activity, no research reports were found which assessed potential synergism between various phytochemicals and BAT.  We previously showed that R combined with genistein (G) and quercetin (Q) reduced weight gain in aged ovariectomized (OVX) female rats. In the current study, OVX rats were fed diets containing varying doses of phytochemicals (diet 1: 1000 mg/kg G; diet 2: 500 mg/kg G, 200 mg/kg R, and 1000 mg/kg Q; diet 3: 1000 mg/kg G, 400 mg/kg R, and 2000 mg/kg Q). After 16 weeks, rats were euthanized and scapular BAT was removed and weighed. Rats in the high dose treatment group had a significantly smaller scapular BAT depot compared to non-OVX controls (0.74g v 0.92g; p<0.05). We hypothesized that the reduction in BAT mass may be due to increased lipid metabolism in BAT. Mitochondrial protein was measured and total lipid content was determined following chloroform/methanol extraction with butylated hydroxytoluene. All treatment groups had a reduction in lipid content compared to non-OVX rats (p<0.07). In summary, the reduction in BAT weight in the high dose group was accompanied by a reduction in lipid content with comparable protein concentrations to BAT from the non-OVX controls. This finding indicates an increase in mitochondrial protein and a reduction in lipid substrate by tissue weight in the BAT of our high dose treatment group, thus indicating a more metabolically active depot. Overall, we conclude that a combination of phytochemicals increases BAT activity in OVX rats. These data may provide further support for the anti-obesity effects of phytochemical combinations that include resveratrol, genistein, and quercetin.

Nothing to Disclose: CNM, SA, EB, NNH, DLH, MAD, SR, CAB

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm

Sources of Research Support: USDA SBIR grant 2012-33610-19474 awarded to SA