What is the central question of this study? How does moderate-intensity aerobic exercise affect the behaviour of purinergic
enzymes in sedentary,
overweight and physically active subjects? What is the relationship between purinergic and inflammatory responses triggered by exercise? What is the main finding and its importance? Moderate-intensity aerobic exercise modifies the activity of purinergic
enzymes and the levels of
nucleotides and
nucleosides. These results are similar in subjects with different
biological characteristics.
5'-Nucleotidase activity and
adenosine levels are associated with inflammatory responses. This study suggests that a purinergic pathway is related to the inflammatory responses triggered by exercise.
ABSTRACT: Purinergic signalling is a mechanism of extracellular communication that modulates events related to exercise, such as
inflammation and coagulation. Herein, we evaluated the effects of acute moderate-intensity exercise on the activities of purinergic
enzymes and plasma levels of
adenine nucleotides in individuals with distinct metabolic characteristics. We analysed the relationship between purinergic parameters, inflammatory responses and cardiometabolic markers. Twenty-four healthy males were assigned to three groups: normal weight sedentary (n = 8),
overweight sedentary (n = 8) and normal weight physically active (n = 8). The volunteers performed an acute session of moderate-intensity aerobic exercise on a treadmill at 70% of V̇O2peak ; blood samples were drawn at baseline, immediately post-exercise and at 1 h post-exercise. Immediately post-exercise, all subjects showed increases in
ATP,
ADP,
AMP and p-nitrophenyl
thymidine 5'-monophosphate hydrolysis, while
AMP hydrolysis remained increased at 1 h after exercise. High-performance liquid chromatography analysis demonstrated lower levels of
ATP and
ADP at post- and 1 h post-exercise in all groups. Conversely,
adenosine and
inosine levels increased at post-exercise, but only
adenosine remained augmented at 1 h after exercise in all groups. With regard to inflammatory responses, the exercise protocol increased tumour
necrosis factor α (TNF-α) and
interleukin 8 (IL-8) concentrations in all subjects, but only TNF-α remained elevated at 1 h after exercise. Significant correlations were found between the activity of
5'-nucleotidase,
adenosine levels, V̇O2peak ,
triglyceride, TNF-α and
IL-8 levels. Our findings suggest a purinergic signalling pathway that participates, at least partially, in the inflammatory responses triggered by acute moderate-intensity exercise. The response of soluble
nucleotidases to acute moderate exercise appears to be similar between subjects of different
biological profiles.