PURPOSE: Tryptophan (TRP) degradation through the kynurenine pathway is responsible for converting 95% of free TRP into kynurenines, which modulate skeletal muscle bioenergetics, immune and central nervous system activity. Therefore, changes in the kynurenines during exercise have been widely studied but not in the context of the effects of remote ischemic preconditioning (RIPC). In this study, we analyzed the effect of 14-day RIPC training on kynurenines and TRP in runners after running intervals of 20 × 400 m. METHODS: In this study, 27 semi-professional long-distance runners were assigned to two groups: a RIPC group performing 14 days of RIPC training (n = 12), and a placebo group, SHAM (n = 15). Blood was collected for analysis before, immediately after, and at 6 h and 24 h after the run. RESULTS: After the 14-day RIPC/SHAM intervention, post hoc analysis showed a significantly lower concentration of XANA and kynurenic acid to kynurenine ratio (KYNA/KYN) in the RIPC group than in the SHAM group immediately after the running test. Conversely, the decrease in serum TRP levels was higher in the RIPC population. CONCLUSION: RIPC modulates post-exercise changes in XANA and TRP levels, which can affect brain health, yet further research is needed.

• Keywords
• kynurenic acid, limb ischemia, long-distance runner, neuro-protective metabolites, tryptophan, xanthurenic acid,
• Publication type
• Journal Article MeSH

Exercise-induced inflammation can influence iron metabolism. Conversely, the effects of vitamin D3, which possesses anti-inflammatory properties, on ultramarathon-induced heart damage and changes in iron metabolism have not been investigated. Thirty-five healthy long-distance semi-amateur runners were divided into two groups: one group received 150,000 IU of vitamin D3 24 h prior to a race (n = 16), while the other group received a placebo (n = 19). Serum iron, hepcidin (HPC), ferritin (FER), erythroferrone (ERFE), erythropoietin (EPO), neopterin (NPT), and cardiac troponin T (cTnT) levels were assessed. A considerable effect of ultramarathon running on all examined biochemical markers was observed, with a significant rise in serum levels of ERFE, EPO, HPC, NPT, and cTnT detected immediately post-race, irrespective of the group factor. Vitamin D3 supplementation showed a notable interaction with the UM, specifically in EPO and cTnT, with no other additional changes in the other analysed markers. In addition to the correlation between baseline FER and post-run ERFE, HPC was modified by vitamin D. The ultramarathon significantly influenced the EPO/ERFE/HPC axis; however, a single substantial dose of vitamin D3 had an effect only on EPO, which was associated with the lower heart damage marker cTnT after the run.

• Keywords
• erythroferrone, erythropoietin, ferritin, iron, ultramarathon, vitamin D,
• MeSH
• Biomarkers * blood   MeSH
• Cholecalciferol * administration & dosage   MeSH
• Adult MeSH
• Double-Blind Method MeSH
• Erythropoietin blood   administration & dosage   MeSH
• Hepcidins blood   MeSH
• Middle Aged MeSH
• Humans MeSH
• Marathon Running * physiology   MeSH
• Heart Diseases prevention & control   etiology   MeSH
• Dietary Supplements * MeSH
• Troponin T blood   MeSH
• Iron * blood   administration & dosage   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Randomized Controlled Trial MeSH
• Names of Substances
• Biomarkers * MeSH
• Cholecalciferol * MeSH
• Erythropoietin MeSH
• Hepcidins MeSH
• Troponin T MeSH
• Iron * MeSH

In humans, most free tryptophan is degraded via kynurenine pathways into kynurenines. Kynurenines modulate the immune system, central nervous system, and skeletal muscle bioenergetics. Consequently, kynurenine pathway metabolites (KPMs) have been studied in the context of exercise. However, the effect of vitamin D supplementation on exercise-induced changes in KPMs has not been investigated. Here, we analyzed the effect of a single high-dose vitamin D supplementation on KPMs and tryptophan levels in runners after an ultramarathon. In the study, 35 amateur runners were assigned into two groups: vitamin D supplementation group, administered 150,000 IU vitamin D in vegetable oil 24 h before the run (n = 16); and control (placebo) group (n = 19). Blood was collected for analysis 24 h before, immediately after, and 24 h after the run. Kynurenic, xanthurenic, quinolinic, and picolinic acids levels were significantly increased after the run in the control group, but the effect was blunted by vitamin D supplementation. Conversely, the decrease in serum tryptophan, tyrosine, and phenylalanine levels immediately after the run was more pronounced in the supplemented group than in the control. The 3-hydroxy-l-kynurenine levels were significantly increased in both groups after the run. We conclude that vitamin D supplementation affects ultramarathon-induced changes in tryptophan metabolism.

• Keywords
• kynurenine, skeletal muscle damage, ultramarathon, vitamin D,
• MeSH
• Central Nervous System metabolism   MeSH
• Kynurenine * metabolism   MeSH
• Humans MeSH
• Dietary Supplements MeSH
• Tryptophan * metabolism   MeSH
• Vitamin D MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Randomized Controlled Trial MeSH
• Names of Substances
• Kynurenine * MeSH
• Tryptophan * MeSH
• Vitamin D MeSH

Human adipocytes release multiple adipokines into the bloodstream during physical activity. This affects many organs and might contribute to the induction of inflammation. In this study, we aimed to assess changes in circulating adipokine levels induced by intense aerobic and anaerobic exercise in individuals with different adipose tissue content. In the quasi-experimental study, 48 male volunteers (aged 21.78 ± 1.98 years) were assigned to groups depending on their body fat content (BF): LBF, low body fat (<8% BF, n = 16); MBF, moderate body fat (8−14% BF, n = 19); and HBF, high body fat (>14% BF, n = 13). The volunteers performed maximal aerobic effort (MAE) and maximal anaerobic effort (MAnE) exercises. Blood samples were collected at five timepoints: before exercise, immediately after, 2 h, 6 h, and 24 h after each exercise. The selected cytokines were analyzed: adiponectin, follistatin-like 1, interleukin 6, leptin, oncostatin M, and resistin. While the participants’ MAnE and MAE performance were similar regardless of BF, the cytokine response of the HBF group was different from that of the others. Six hours after exercise, leptin levels in the HBF group increased by 35%. Further, immediately after MAnE, resistin levels in the HBF group also increased, by approximately 55%. The effect of different BF was not apparent for other cytokines. We conclude that the adipokine exercise response is associated with the amount of adipose tissue and is related to exercise type.

• Keywords
• IL-6, adipose tissue, anaerobic exercise, endurance exercise, leptin, resistin,
• MeSH
• Adipokines * blood   MeSH
• Adiponectin MeSH
• Exercise physiology   MeSH
• Cytokines MeSH
• Leptin MeSH
• Humans MeSH
• Resistin MeSH
• Adipose Tissue * physiology   MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Adipokines * MeSH
• Adiponectin MeSH
• Cytokines MeSH
• Leptin MeSH
• Resistin MeSH

Changes of circulating free plasma DNA (cfDNA) are associated with different types of tissue injury, including those induced by intensive aerobic and anaerobic exercises. Observed changes are dependent from induced inflammation, and thus it may be a potential marker for athletic overtraining. We aimed to identify the response of cfDNA to different types of exercise, with association to exercise intensity as a potential marker of exercise load. Fifty volunteers (25 athletes and 25 physically active men) were assigned to the study and performed maximal aerobic (Bruce test) and anaerobic (Wingate Anaerobic Test) test. Blood samples for cfDNA analysis were collected at four time-points: before, 2-5 min after, 30 min after and 60 min after each type of maximal physical activity. The two-way ANOVA revealed a significant effect of group factor on serum cfDNA concentrations (32.15% higher concentration of cfDNA in the athletes). In turn the results of the post hoc test for the interaction of the repeated measures factor and the group showed that while the concentration of cfDNA decreased by 40.10% in the period from 30 min to 60 min after exercise in the control group, the concentration of cfDNA in the group of athletes remained at a similar level. Our analysis presents different responses depending on the intensity and duration of exercise. Our observations imply that formation of cfDNA is associated with response to physical activity but only during maximal effort.

• Keywords
• aerobic exercise, anaerobic exercise, cfDNA, exercise load,
• MeSH
• Biomarkers blood   MeSH
• Adaptation, Physiological * MeSH
• Humans MeSH
• Young Adult MeSH
• Sports * MeSH
• Case-Control Studies MeSH
• Cell-Free Nucleic Acids blood   MeSH
• Check Tag
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Biomarkers MeSH
• Cell-Free Nucleic Acids MeSH