Сytokine levels during physical exercise and upon meldonium treatment

Signaling molecules (cytokines) play a key role in communications between the immune cells. The main cytokines involved in extracellular matrix remodeling include interleukins and TNFα. IL-6, IL-18 act as pro-inflammatory, and the cytokine IL-10 is anti-inflammatory. TNFα stimulates the production of IL-1, IL-6, IL-18. The cytokine IL-10 affects immunoregulation and inflammation. In recent years, there has been a search for therapeutic agents to correct the cytokine profile. Meldonium is a drug with a broad spectrum of action. The aim of our study was to assess the levels of IL-6, IL-10, IL-18, TNFα during physical activity and when using meldonium. The experiment was conducted in two stages: the first, when the animals performed physical activity without meldonium treatment (n = 36); the second stage (swimming) was performed and combined with simultaneous meldonium treatment (n = 36). A total of 10 swimming sessions were conducted. Meldonium was added to the food of experimental animals for 10 days. The animals were taken out of the experiment immediately after the end of the last session of swimming, and 30 days after the end of the experiments. The concentration of IL-6, IL-10, IL-18, TNFα was determined in blood plasma samples. With strenous physical activity without usage of meldonium, TNFα, IL-6 and IL-18 increased immediately after the experiment and 30 days after the end of the experiments, along with decreased IL-10 levels. Meldonium treatment during heavy physical exercise immediately after the end of the experiment led to a decrease in the level of TNFα, IL-6 and IL-18, along with increased concentration of IL-10 in blood plasma. 30 days after the end of the experiments, the studied cytokines approached the values of the intact group. Heavy physical exercise (without the use of meldonium) led to shifts in the cytokine profile, i.e., the concentration of TNFα, IL-6, IL-10, IL-18 showed sufficient changes. Under the conditions of meldonium use, an increase in the anti-inflammatory cytokine (IL-10) was noted, along with a systemic decrease in TNFα, IL-6, IL-18 levels.