Impact of diets enriched with pomegranate seed oil on the development of obesity in Danio rerio model

The prevalence of obesity has increased steadily over the past decades and is expected to continue along this trend unless immediate action is taken. In 2016, this major public health issue was affecting more than 650 million obese individuals, causing a decrease in the quality of life, a higher mortality rate due to numerous associated risk factors and an increase in overall health-care costs. Currently the most long-term effective intervention against obesity is gastric bypass, which in itself can pose health risks to patients. Another approach to address the obesity epidemic is to prevent the progression of obesity. In this sense certain dietary fatty acids are emerging as novel treatments. We are particularly interested in examining the anti-obesity effects of pomegranate seed oil (PSO) due to its high content in conjugated linolenic acids (CLnAs). In the framework of this Master’s thesis, the anti-obesity properties of PSO were investigated on the in vivo model Danio rerio using Artemia as fatty acids vehicles. D. rerio possess all the key organs and metabolic mechanisms required to study lipid metabolism and the development of obesity while Artemia are easily enriched with any types of oils and are well accepted by the fish as a source of food. To achieve our objectives, sixty fish were fed with custom formulated diets. A total of four diets were established under two experimental conditions: The type of oil used for enrichment and the caloric content. After six weeks of the feeding experiment, the physiological parameters and the fatty acid profiles of the fish were analysed. This Master’s thesis suggests promising anti-obesity properties of PSO in a high caloric diet. For the first time to our knowledge, the BMI of fish overfed with a PSO diet was significantly lower than the control group while both groups were iso-calorically overfed. The observed results also reveal significantly higher levels of CLnAs (punicic acid, α-eleostearic acid and catalpic acid) and conjugated linoleic acids (CLAs: rumenic acid and C18:2 t9,t11) in fish fed with a PSO diet, confirming the bioconversion from some CLnAs to CLAs via a ∆13-saturation reaction in D. rerio. Having achieved the objectives set during this Master’s thesis, we can now turn our attention to the many new questions and perspectives that emerged to deepen our knowledge about the properties of PSO on the development of obesity and its comorbidities.