Effect of Treadmill Exercise and Hydrogen-rich Water Intake on Serum Oxidative and Anti-oxidative Metabolites in Serum of Thoroughbred Horses

Abstract

The present study aimed to clarify changes of oxidative stress and antioxidative functions in treadmill-exercised Thoroughbred horses (n=5, 3 to 7 years old), using recently developed techniques for measurement of serum d-ROMs for oxidative stress, and BAP for antioxidative markers. Also, the effect of nasogastric administration of hydrogen-rich water (HW) or placebo water preceding the treadmill exercise on these parameters was examined. Each horse was subjected to a maximum level of treadmill exercise in which the horses were exhausted at an average speed of 13.2 ± 0.84 m/sec. Blood samples were taken 4 times, immediately before the intake of HW or placebo water at 30 min preceding the treadmill exercise, immediately before the exercise (pre-exercise), immediately after the exercise (post-exercise) and at 30 min following the exercise. In all horses, both d-ROMs and BAP values significantly increased at post-exercise. The increase in d-ROMs tended to be lower in the HW trial, as compared to the placebo trial at pre-exercise. The increase in BAP was considerable at approximately 150% of the pre-exercise values in both the HW and placebo treatment trials. The BAP/d-ROMs ratio was significantly elevated at post-exercise in both treatment trials, while a significant elevation was also observed at pre-exercise in the HW trial. BAP, d-ROM, and the BAP/d-ROM ratio tended to decline at 30 min after the exercise, except BAP and BAP/d-ROMs in the placebo trial. These results demonstrate that the marked elevation of oxidative stress and anitioxidative functions occurred simultaneously in the intensively exercised horses, and suggest a possibility that HW has some antioxidative efficacy.

Keywords: BAP; Thoroughbred; d-ROMs; exercise; hydrogen-water.

Fig. 1.

An illustration of the overall experimental procedure of the present study. Horses were exercised with increment of load every 2 min at speeds of 1.6, 3.6, 7, 10, 12 and 13 m/s until they were exhausted. The first treadmill exercise was performed after placebo administration and the second treadmill exercise was performed after hydrogen-rich water (HW) administration, after one-week interval. Two litters of placebo water or HW were administered to the esophagus by a nasogastric catheter in each horse at 30 min before the treadmill exercise. Blood samples (serum) were collected 4 times: 30 min before the exercise, immediately before the exercise, post-exercise, and at 30 min after the exercise.

Fig. 2.

d-ROMs values at pre-exercise, post-exercise and 30 min after exercise of each horse after administration of placebo and HW.

Fig. 3.

Average changes of d-ROMs of all horses after administration of placebo and HW. “30 min”: at 30 min after the treadmill exercise. Data are shown as means ± SE.

Fig. 4.

BAP values at pre-exercise, post-exercise and 30 min after exercise of each horse after administration of placebo and HW.

Fig. 5.

Average changes of BAP of all horses after administration of placebo and HW. “30 min” : at 30 min after the treadmill exercise. Data are shown as means ± SE.

Fig. 6.

Average changes of BAP/d-ROMs of all horses after administration of placebo and HW. “30 min”: at 30 min after the treadmill exercise. Data are shown as means ± SE.