Global epidemic of overweight and obesity has intensified over the years. According to the WHO report in 2016, about 1.9 billion adults (39%) aged 18 years and over were overweight and 13% were obese. Obesity can lead to a higher mortality by increasing the risks of diabetes, metabolic disorders, cardiovascular diseases, sleep apnea, and cancer etc. It could also promote chronic systemic inflammation affecting many human organs and nervous systems. Diet-induced obesity in Drosophila has been established by chronic feeding of high sugar or fat diet. Many components in fat metabolism and insulin signaling pathways are conserved between humans and flies. Similarly, obese flies showed accumulated triacylglycerol, insulin resistance, lower fitness, and elevated risks for kidney and cardiovascular diseases. Thus, flies were increasingly used as a genetic tool for modeling obesity and metabolic diseases. Previously, coconut oil was mostly used for excess dietary experiments in flies. However, the liquidness and greasiness may interfere with the direct effect of excessive consumption of fat. In addition, global oil consumption and production data showed that coconut oil might not always be a major fat source for different population or in different regions. In this study, we compared the effects of diet supplemented with different fat sources. Our result suggested that excessive pork fat (HP) and palm oil (HM) exerted more significant effects based on the biological responses and fitness evaluation. Also fly fed by different high fat diets showed different expression pattern. Natural remedy such as cinnamon and EGCG have been implied to prevent obesity and inflammation. Based on our HFD model, cinnamon and EGCG could reduce the negative impact of high fat diet in flies.
Keywords: High fat diet/obesity/anti-obesity/Drosophila model