Chronic inflammation and neutrophil activation as possible causes of joint diseases in ballet dancers

Abstract

Herein, we investigated the effects of a ballet class on the kinetic profiles of creatine kinase (CK) and lactate dehydrogenase (LDH) activities, cytokines, complement component 3 (C3), and the concentrations of immunoglobulin (Ig), IgA and IgM, in ballerinas. We also verified neutrophil death and ROS release. Blood samples were taken from 13 dancers before, immediately after, and 18 hours after a ballet class. The ballet class increased the plasma activities of CK-total (2.0-fold) immediately after class, while the activities of CK-cardiac muscle (1.0-fold) and LDH (3.0-fold) were observed to increase 18 hours after the class. Levels of the TNF-α , IL-1β, IgG, and IgA were not affected under the study conditions. The exercise was found to induce neutrophil apoptosis (6.0-fold) 18 hours after the ballet class. Additionally, immediately after the ballet class, the neutrophils from the ballerinas were found to be less responsive to PMA stimulus.

Conclusion: Ballet class was found to result in inflammation in dancers. The inflammation caused by the ballet class remained for 18 hours after the exercise. These findings are important in preventing the development of chronic lesions that are commonly observed in dancers, such as those with arthritis and synovitis.

Figure 1

Effect of classical ballet on muscle lesion markers. Serum concentrations of CK-NAC (a), CK-MB (b), and LDH (c) in dancers were determined before, immediately after, and 18 hours after a ballet class. The values are presented as mean ± standard error of 13 dancers and are presented as relative unit (UR). Figures were plotted with the data of the variations in markers during a ballet class, thus indicating the normalization between the values of before and after a ballet class. *P < 0.05 for comparison to preclass condition and ^# P < 0.05 for comparison to immediately after ballet class condition.

Figure 2

Neutrophil DNA fragmentation (%) in ballet dancers determined before, immediately after, and 18 hours after a ballet class. The values are presented as the mean ± standard error of 13 dancers. *P < 0.05 for comparison to preclass and ^# P < 0.05 for comparison to immediately after ballet class.

Figure 3

ROS release by neutrophils in ballet dancers was determined before, immediately after, and 18 hours after a ballet class. The measurements were performed under basal and PMA-stimulated conditions. The values are presented as the means ± standard errors of 13 dancers.

Figure 4

Chronic inflammations as a result of ballet dancing class causes subclinical systemic inflammation and the activation of the function of neutrophils in the chronic inflammation may be the main factor involved in the genesis of arthritis and other inflammatory joint diseases in ballerinas.