Abstract: Purpose: To investigate the possible mechanism of neoagarotetraose (NAT) in regulating lipid metabolism. Methods: Male BALB/C mice were randomly divided into three groups: control group, exhaustive exercise group and NAT intervention group. A wheel-track treadmill was used in this study to propose an exhaustive exercise protocol. The animals in both the exhaustive exercise and NAT groups were subjected to exhaustive exercise, while those in the control group maintained normal physical activity. After sixteen consecutive days of treatment, serum lipid parameters were measured and fecal samples were collected to investigate gut microbiota changes by metagenome sequencing. Our results showed that the concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in serum increased sharply (P < 0.05) after exhaustive exercise, while serum triglycerides (TG) concentration decreased significantly (P < 0.05) indicating that exhaustive exercise could be an important cause of lipid metabolism disorder. Our data also showed that NAT treatment resulted in a profound change in the gut microbiome structure, which subsequently led to widespread shifts in its function. Meanwhile, our findings suggested that NAT may protects mice against dyslipidemia induced by exhaustive exercise through modulating the gut microbial composition, improving the lipid metabolism signal pathway of the microbiota, and regulating enzymes activities involved in fatty acid oxidation and lipid synthesis.

Key words: neoagarotetraose, exhaustive exercise, dyslipidemia, gut microbiota, metagenome