Nitrosative stress-based specific evaluation of creatine use in combination with aerobic running exercise at different speeds: a preclinical study in mice.

Objective: In acute and chronic aerobic exercise, skeletal muscle and liver are the main organs that adapt and regulate metabolic activity. The levels of nitrosative stress caused by exercise in these organs are extremely important in the continuity of exercise, its health-promoting benefits, and the evaluation of therapeutic efficacy. In this study, nitrosative stress levels were investigated in musculus quadriceps femoris tissue and liver tissue of mice that were given low and high-speed aerobic running exercise and also received Cr supplementation.

Materials And Methods: In this study, nitrosative stress levels were investigated in the muscle/liver tissue of 42 BALB/c mice that were given low and high-speed aerobic running exercise and creatine monohydrate (Cr) (40 mg/kg of diet daily) supplementation with exercise. The study included six groups with and without Cr supplementation, low-speed aerobic running, high-speed aerobic running, and no exercise. The mice in groups with low-speed and high-speed aerobic exercise with and without Cr supplementation were run on the treadmill for 8 weeks. Then, nitric oxide (NO·), nitric oxide synthase (NOS), and peroxynitrite (ONOO-) levels in muscle/liver tissue were measured by spectrophotometric method.

Results: It was found that the nitrosative stress level in the groups that did low and high-speed aerobic running exercises increased compared to the group that did not exercise. It was found that NO· decreased NOS activity and ONOO- level increased in muscle tissues of low and high-speed aerobic exercise groups that received Cr supplementation compared to those that did not. However, NO· and ONOO- levels in liver tissue decreased while NOS activity did not change. The lowest level of nitrosative stress in both muscle and liver tissue was found in the low-speed exercise group receiving Cr supplementation.

Conclusions: Although supplements in exercise are an important component, the simultaneously measured nitrosative stress level is critical in determining the optimal exercise.