Changes in immunological parameters in ultramarathon runners depending on the duration of the load

BACKGROUND

In recent decades, there has been an increasing interest in long-distance running, not only to the classic marathon distances but also to an ultramarathon -100 km, 250 km, and multi-day races. One of the most reactive body systems in conditions of prolonged muscular loads is the immune system. The work aimed to investigate the changes in immunological parameters in runners for extra-long distances of various durations.

METHODS

We examined 73 male athletes specializing in long-distance and ultra-long-distance running. The design of the survey included the study of immunological status during the marathon race, 100 km run, and six-day run. We studied the dynamics of leukocyte formula; subpopulations of lymphocytes; fractions of immunoglobulins: IgA, IgM, IgG; phagocytic activity.

RESULTS

During the marathon run, athletes' immunological changes are manifested by the development of neutrophilic leukocytosis with a decrease in the phagocytic activity of neutrophils. There was a sharp increase in the NLR and decrease in the LMR. A 100-km race caused a decrease in the absolute and relative number of T-lymphocytes. NLR increased almost ten times, and LMR, on the contrary, decreased nearly five times. On the first day of the 6-days run, there is a sharp increase in NLR and a decrease in LMR, after which there is a relative stabilization of both indicators.

CONCLUSIONS

Changes in immunological parameters during jogging are closely related to the duration of the load. The most pronounced changes are observed on the part of neutrophils and lymphocytes.

Pterins as Diagnostic Markers of Mechanical and Impact-Induced Trauma: A Systematic Review

We performed a systematic review of the literature to evaluate pterins as biomarkers of mechanical and impact-induced trauma. MEDLINE and Scopus were searched in March 2019. We included in vivo human studies that measured a pterin in response to mechanical or impact-induced trauma with no underlying prior disease or complication. We included 40 studies with a total of 3829 subjects. Seventy-seven percent of studies measured a significant increase in a pterin, primarily neopterin or total neopterin (neopterin + 7,8-dihydroneopterin). Fifty-one percent of studies measured an increase within 24 h of trauma, while 46% measured increases beyond 48 h. Pterins also showed promise as predictors of post-trauma complications such as sepsis, multi-organ failure and mortality. Exercise-induced trauma and traumatic brain injury caused an immediate increase in neopterin or total neopterin, while patients of multiple trauma had elevated pterin levels that remained above baseline for several days. Pterin concentration changes in response to surgery were variable with patients undergoing cardiac surgery having immediate and sustained pterin increases, while gastrectomy, liver resection or hysterectomy showed no change. This review provides systematic evidence that pterins, in particular neopterin and total neopterin, increase in response to multiple forms of mechanical or impact-induced trauma.

Pterins as diagnostic markers of exercise-induced stress: a systematic review

OBJECTIVES

To evaluate pterins as diagnostic biomarkers of exercise-induced stress.

DESIGN

Systematic review of the literature.

METHODS

MEDLINE, Scopus and Web of Science were searched in March 2019 for relevant literature. We only considered in vivo studies of healthy humans that reported measurement of a pterin(s) in response to exercise or sport with no underlying prior disease or complication. Relevant articles were independently reviewed and resolved by consensus.

RESULTS

We included 29 studies with 644 participants. We classified articles by running/hiking, cycling, rugby, mixed martial arts (MMA) or other. Eighty-six percent of studies measured a significant increase in a pterin in response to exercise. Changes in pterin concentrations were within 24h of the exercise-stimulus in 79% of studies and 17% measured a change from baseline greater than 48h post-exercise (49% did not measure or report beyond 48h). Neopterin or total neopterin (neopterin+7,8-dihydroneopterin) were the primary pterin measured (28 studies) and they were equally sensitive to exercise regardless of whether the stimulus was running, cycling, rugby, MMA or other.

CONCLUSIONS

Neopterin and total neopterin increase in response to exercise-induced stress. Pterins may have limited capacity for monitoring long-term stress beyond 48h but further research is required.

Neopterin, Inflammation, and Oxidative Stress: What Could We Be Missing?

Neopterin has been extensively used as a clinical marker of immune activation during inflammation in a wide range of conditions and stresses. However, the analysis of neopterin alone neglects the cellular reactions that generate it in response to interferon-γ. Neopterin is the oxidation product of 7,8-dihydroneopterin, which is a potent antioxidant generated by interferon-γ-activated macrophages. 7,8-Dihydroneopterin can protect macrophage cells from a range of oxidants through a scavenging reaction that generates either neopterin or dihydroxanthopterin, depending on the oxidant. Therefore, plasma and urinary neopterin levels are dependent on both macrophage activation to generate 7,8-dihydroneopterin and subsequent oxidation to neopterin. This relationship is clearly shown in studies of exercise and impact-induced injury during intense contact sport. Here, we argue that neopterin and total neopterin, which is the combined value of 7,8-dihydroneopterin and neopterin, could provide a more comprehensive analysis of clinical inflammation than neopterin alone.