Effects of different diet administration on energy balance, metabolic efficiency and inflammatory state in an animal model

My research project aims to evaluate the possible beneficial effects of Omega (ω)-3 polyunsaturated fatty acids (PUFA) administration in an experimental animal model. I performed the research activity with two different experimental approaches. In the first experimental project, it was used an animal model with obesity-diet induced. Male Wistar rats were fed, for 6 weeks, with three different diets: standard diet (control); HFD enriched with saturated fatty acids (lard); HFD enriched with ω-3 (PUFA) derived from fish oil. In the second experimental project, the rats were fed with standard diet for 4 weeks and two groups received a supplementation with two different milk: the first group were supplemented with low forage milk (LFM), the second group was supplemented with milk low in ω6:ω3 ratio and high conjugated linoleic acid (CLA) levels a high forage milk (HFM). In both experimental projects, at the end of the experimental period was assessed the effects of these dietary treatments on energy balance, lipid metabolism and inflammatory state. Since the skeletal muscle shares with the liver the capacity to influence energy metabolism throughout the body, this work investigated the ability of PUFA to affects lipid metabolism and inflammatory state by modulating the mitochondrial function, ROS emission and Nrf-2 activation in these tissues. Diet supplementation with ω-3 (PUFA) results in a significant decrease in whole body weight, lipid utilization and inflammation with an increased energy expenditure due to the modulation of skeletal muscle and liver mitochondrial efficiency, and to an increased AMPK activation with a consequent reduction of oxidative stress. Moreover, the increased mitochondrial respiration rates were related to an increased mitochondria biogenesis as shown by the increase in PGC1-α and –β expression levels in ω-3 fish oil treated rat models. Furthermore, my data provided the first evidence of HFM beneficial effects on rat metabolism, and suggested that these effects are mediated by the high ω6/ω3 ratio and high content of CLA of HFM.