Dynamics of Lipid Metabolism in Volunteers during Short-Term Isolation in a Hermetic Chamber

In this study we have examined the crew of the SIRIUS 17 international experiment with a 17-day isolation in a hermetic chamber. The experiment was conducted at the experimental facilities of the Institute of Biomedical Problems, Russian Academy of Sciences. The crew consisted of six people of both sexes aged 27 to 43 years. We measured the serum level of total cholesterol, high-density lipoprotein cholesterol (HDL), apolipoproteins A1 and B, phospholipids, triglycerides, nonesterified (free) fatty acids, and β-hydroxybutyrate. Then we calculated the concentrations of low-density lipoprotein cholesterol (LDL) and very-low-density lipoprotein cholesterol (VLDL) and the values of atherogenic index (IA), ApoB/ApoA1 and phospholipids/cholesterol (PL/CHO) ratios. It was found that the “basic” parameters of cholesterol metabolism (cholesterol, HDL and LDL cholesterol, IA, the ratio of FL/CHO) were almost constant during the experiment, while the parameters indicative of the changes in the lipoprotein spectrum were changing, which reflects atherogenesis. The content of VLDL cholesterol, triglycerides, and ApoB was increasing, as did the value of the ApoB/ApoA1 index. Thus, even a short-term effect of the factors of hermetic chamber leads to the initial shifts in lipid metabolism, which indicate the activation of atherogenesis processes. Our findings show that further studies are needed to investigate the changes in lipid metabolism in experiments with longer periods of isolation.