Free form astaxanthin from yeast Phaffia rhodozyma fermentation reduces plasmatic triglycerides in a pre-obesity diet-induced dyslipidaemia mouse model

Previous work have indicated a lipid-lowering effect of esterified astaxanthin (AX) from algae Haematococcus pluvialis. The aim of this study was to set up a murine model of pre-obesity diet-induced dyslipidaemia to investigate the lipid-lowering effect of free-form AX from yeast Phaffia rhodozyma fermentation. After 6 weeks on high-fat diet, 32 male C57BL/6 mice were divided into 4 groups fed (1) a standard or (2-4) a high-fat diet (HFD) supplemented or not with AX at 0.03% or 0.06% for 8 weeks. Animals were anesthetized and sacrificed and biological samples (plasma and internal organs) collected and stored at -80 degrees C. The plasma concentrations of triglycerides and cholesterol were determined and gene expression measured for markers of energy metabolism in the liver and adipose tissue. Statistical analyses were performed using SPSS software and the significance set at p< 0.05. Primary results showed a lowering effect on the triglyceride levels (-35 to-45%, p< 0.05) in the groups fed high-fat-diet supplemented with AX, but no effect on cholesterol. Genetic expression showed a modulation of various mechanisms of energy regulation, from lipid transporters to beta-oxidation pathways and insulin resistance. The associated effects could also have implications for the prevention of metabolic syndrome.