Blood glutathione status and activity of glutathione-metabolizing antioxidant enzymes in erythrocytes of young trotters in basic training.

The research looks at how strenuous training protocols influence the glutathione status and antioxidant enzyme activity in the blood of young trotters (specific breed of horses). Essentially, the study suggests that the high-intensity training routine leads to a potential imbalance in the horse’s antioxidant defenses, indicating the need for diet optimization and training protocol revisions.

Research Design and Execution

• The researchers investigated 9 untrained trotters, aged between 16 and 20 months, subjected to a 4-month basic training program. The exercises ranged from low-to-moderate intensity and the horses were made to run distances varying from 4 to 40 km a week, with workloads increased every 3 weeks.
• The team used heart rate and blood lactate measurements to monitor exercise intensity. Blood samples were taken at rest, before and after the conditioning period, immediately after routine exercise and 60 min thereafter.

Measurements and Analysis

• The blood samples were analyzed for concentrations of different forms of glutathione (GSH, GSSG, and TGSH). In addition, they recorded the activities of enzymes primarily associated with maintaining the balance of glutathione – glutathione peroxidase (GPX) and glutathione-disulfide reductase (GR).
• The research also examined changes in the levels of oxidized nicotinamide adenine dinucleotide (NAD(+)) and its phosphate (NADP(+)).

Study Findings

• All investigated parameters except NAD(+) and the ratio of reduced-to-oxidized glutathione (GSH/GSSG) were found to get altered during the training period.
• After the workout, GPX, NADP(+), and GSH/GSSG were significantly lower, while GSSG was higher than at rest. The reduction in NADP(+), low GSH/GSSG, and high GSSG concentration persisted even 60 minutes after the exercise.
• Glutathione-disulfide reductase activity was higher post-workout, with the increase being significant only 60 minutes after the exercise.

Conclusion

• The results indicate that the production of harmful oxygen derivatives possibly exceeds the antioxidant capabilities of the trotters, leading to a disrupted balance. This outcome suggests that the training protocol needs to be revised to decrease oxidative stress.
• The researchers recommend adjusting the diet to include more antioxidants and revising the existing basic training protocol.