|Estrogen inhibits the effects of obesity and alcohol on mammary tumors and fatty liver|
Authors: Jina Hong, Valerie B. Holcomb, Kyoko Kushiro, Nomelí P. Núñez
Affiliations: Princeton University, Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA, Department of Nutritional Sciences, The University of Texas at Austin, School of Human Ecology, Austin, TX 78712, USA, The University of Texas at Austin, College of Natural Sciences, School of Human Ecology, Department of Nutritional Sciences, Austin, TX 78712, USA
Published online on: Wednesday, August 17, 2011
The risk of developing breast cancer and fatty liver is increased by alcohol consumption. The objective of the present study was to determine if obesity and exogenous estrogen supplementation alter the effects of alcohol on mammary tumorigenesis and fatty liver. Ovariectomized female mice were (1) fed diets to induce overweight and obese phenotypes, (2) provided water or 20% alcohol, (3) implanted with placebo, low- or high-dose estrogen pellets and (4) injected with Met-1 mouse mammary cancer cells. Alcohol-consuming mice were more insulin sensitive and developed larger tumors than water consuming mice. Obese mice developed slightly larger tumors than control mice. Alcohol consumption and obesity increased growth factors, hepatic steatosis, activation of Akt, and inhibited the caspase-3 cascade. Estrogen treatment triggered the loss of body fat, induced insulin sensitivity, suppressed tumor growth, reduced growth factors and improved hepatic steatosis. Results show that the effects of alcohol on mammary tumor and fatty liver are modified by obesity and estrogen supplementation.