The role of melatonin, IL-6, and IL-10 in the immunopathogenesis and clinical course of tuberculosis

BACKGROUND. The present day dictates a new relevance of tuberculosis, which consists in the increase in the number of patients with resistant forms of tuberculosis and the decrease in treatment adherence due to the long duration and toxicity of antimycobacterial therapy. Treatment regimens should be adjusted to include additional non-microbial agents that can simulate the immune system's activity in combating mycobacteria and synergistically enhance the activity of anti-tuberculosis drugs themselves. MATERIALS AND METHODS. The determination of melatonin levels and cytokine levels (interleukin-6 and -10) in blood plasma was performed during the first 2 weeks of antimycobacterial treatment. The study included 30 patients with new cases of pulmonary tuberculosis with preserved sensitivity and 30 patients with multidrug resistance. RESULTS AND DISCUSSION. It was found that the level of melatonin in the blood plasma in the study groups was significantly lower compared to the control group. The average value of melatonin was 33.2±1.2 pg/ml in group 1 and 29.4±2.3 pg/ml in group 2 and in the control group – 46.2±0.8 pg/ml (p=0.035). It was proven that the content of interleukin-6 in the studied groups of patients significantly exceeded the practically healthy individuals indicator: in group 1, the level of interleukin-6 was 11.04 times higher, in group 2 – 13.9 times (p<0.001). The concentration of interleukin-10 in the blood plasma of tuberculosis patients is significantly increased: in group 1, the level of interleukin-10 was 2.2 times higher, in group 2 – 1.7 times (p<0.001). The linear correlation coefficient showed that in tuberculosis patients, there is almost no correlation between the level of interleukin-6 and melatonin (r=0.14), and there is a positive, close relationship between the level of interleukin-10 and melatonin (r=0.73).