Abstract: Objective: The effect of the natural antioxidant astaxanthin on the function of the human body was studied by using nuclear magnetic resonance (NMR)-based metabonomics from the aspects of metabolites and metabolic network regulation. Methods: Totally 16 adult males were selected and equally and randomly divided into a control group and an experimental group. The experimental group took astaxanthin at a moderate dose of 12 mg/d for 28 days and the control group took the same dose of a placebo (starch capsule) for 28 days. On the morning of the first day, fasting fingertip blood samples were collected from all the subjects to determine antioxidant capacity and blood lactate values. Blood samples were taken again on the morning of the 29th day, and 5 mL of blood was taken from the elbow vein, followed by three cycles of bicycling for 30 s each at 3 min intervals with a load of 0.075 kg/kg mb. Blood samples were taken for the third time immediately after exercise. A free oxygen radical analyzer was used to determine blood lactate values and antioxidant capacity and nuclear magnetic resonance (NMR) spectroscopy was used to fingerprint vein blood samples. The data extracted from the spectra were processed and analyzed with MestReNova, SIMCA-P, and SPSS software. Results: In the quiet state, 15 potential differential metabolites (DMs) were identified between the two groups, and a total of three metabolic pathways were found to have a great influence on the DMs. The DMs creatine, betaine (Bet), and glycine were involved in the glycine, serine and threonine metabolism pathways, acetoacetic acid and β-hydroxybutyric acid were involved in the ketone body anabolism and catabolism pathways, and alanine, glutamic acid and glutamine were involved in the alanine, aspartic acid and glutamic acid metabolism pathways. Antioxidant capacity was significantly higher in the experimental group than in the control group (P < 0.05), while the opposite was observed for blood lactate values (P < 0.05). Immediately after exercise, three potential DMs were found, and only the alanine, aspartate and glutamic acid metabolic pathways, in which glutamine was involved, were observed to have a great influence on them. After exercise, antioxidant capacity significantly decreased in both groups (P < 0.05), but it was significantly higher in the experimental group than in the control group (P < 0.05); blood lactate values rose significantly after exercise (P < 0.01), and significantly dropped in the experimental group compared with the control group (P < 0.05). Conclusion: Astaxanthin supplementation can cause marked changes in blood metabolites both before and after acute high-intensity exercise, which are involved in amino acid metabolism and lipid metabolism pathways in the body, thereby improving the body’s antioxidant capacity and exercise capacity.

Key words: astaxanthin; acute intense exercise; metabolomics