Influence of acute moderate- to high-intensity aerobic exercise on markers of immune function and microparticles in renal transplant recipients

Effects of Acute Exercise on Cardiac Autonomic Response and Recovery in Non-Dialysis Chronic Kidney Disease Patients

Purpose: Heart rate variability (HRV) has gained acceptance as a key marker of cardiovascular health. We compared HRV responses after continuous moderate-intensity exercise (CMIE) and high-intensity interval exercise (HIIE) matched for intensity and duration in individuals with midspectrum chronic kidney disease (CKD). Methods: Twenty men and women (age 62.0 ± 10 yrs.) diagnosed with CKD stages G3a and G3b participated in a 2 (condition) x 4 (time point) repeated cross-over measures design study. HRV time-domain indices were based on the standard deviation of all NN intervals (SDNN) and the square root of the mean of the sum of the squares of differences between adjacent NN intervals (RMSSD) and frequency domain. High-frequency (HF), low-frequency (LF), total power (TP) were examined. CMIE consisted of treadmill walking for 30 minutes at a 2% incline and speed corresponding to 60%-65% of reserve volume of oxygen (VO2R). HIIE included five intervals of 3 minutes at 90% of VO2R and 2 minutes at 20% VO2R intervals. Conditions were designed to be of the same average intensity (60% to 65% of VO2R) and caloric expenditure (~144 kcal). Results: Immediately following exercise SDNN, RMSSD, HF, LF, and TP were significantly lower compared to before exercise (p <.05). HRV responses were not different between conditions and conditions X time (p >.05). Conclusions: Thirty minutes of either CMIE or HIIE decreased HRV indices, pointing to an autonomic imbalance favoring vagal mediation. HRV's responses regarding HIIE were no different from CMIE, therefore, from an autonomic function point of view this similarity may be useful for CKD exercise prescription and programming.

Post-exercise endothelial function is not associated with extracellular vesicle release in healthy young males

Acute exercise can result in temporary decrease in endothelial functions, which may represent a transient period of risk. Numerous mechanisms underpinning these responses included release of extracellular vesicles (EVs) derived from apoptotic or activated endothelial cells and platelets. This study aims to compare the time course of endothelial responses to moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) and the associations with EV release. Eighteen young healthy males (age: 22.6 ± 3.7 years, BMI: 25.6 ± 2.5 m²/kg, and VO_2peak: 38.6 ± 6.5 mL/kg/min) completed two randomly assigned exercises: HIIE (10 × 1 min-@-90% heart rate reserve (HRR) and 1 min passive recovery) and MICE (30 min-@-70% HRR) on a cycle ergometer. Flow-mediated dilation (FMD) was used to assess endothelial function and blood samples were collected to evaluate endothelial cell-derived EV (CD62E⁺) and platelet-derived EV (CD41a⁺), 10, 60, and 120 min before and after exercise. There were similar increases but different time courses (P = 0.017) in FMD (increased 10 min post-HIIE, P < 0.0001 and 60 min post-MICE, P = 0.038). CD62E⁺ remained unchanged (P = 0.530), whereas overall CD41a⁺ release was reduced 60 min post-exercise (P = 0.040). FMD was not associated with EV absolute release or change (P > 0.05). Acute exercise resulted in similar improvements, but different time course in FMD following either exercise. Whilst EVs were not associated with FMD, the reduction in platelet-derived EVs may represent a protective mechanism following acute exercise.

Physical performance capacity after pediatric kidney transplant and clinical parameters associated with physical performance capacity

BACKGROUND

History of chronic kidney disease and kidney transplantation is known to influence physical performance capacity. The aim of this study was to compare the physical performance of pediatric kidney transplant recipients to healthy controls and to find possible correlations between clinical parameters and physical performance capacity.

METHODS

Twenty-four pediatric kidney transplant recipients (62.5% boys) were tested at a median age of 10.8 years. Physical performance capacity was tested with a test set including six different components assessing muscle endurance, strength, speed, and flexibility. The control group consisted of 273 healthy age-matched schoolchildren. Clinical parameters were collected as part of routine follow-up protocol. The majority of patients (62.5%) had congenital nephrotic syndrome of Finnish type (CNS) as primary diagnosis, and therefore, the results of CNS recipients were compared to the other disease groups.

RESULTS

The physical performance capacity in pediatric kidney transplant recipients was lower compared to healthy controls. Surprisingly, no statistically significant correlation was found between graft function and physical performance capacity. The CNS patients scored worse than patients with other diagnoses in all test domains except for sit-and-reach and shuttle run, but the differences did not reach statistical significance.

CONCLUSION

The physical performance of pediatric kidney transplant recipients is reduced, especially in those with congenital nephrotic syndrome. Clinical parameters, including graft function, did not predict physical performance capacity, suggesting that the reduced physical performance seems to be of multivariable cause. A higher resolution version of the Graphical abstract is available as Supplementary information.

A Guide to Different Intensities of Exercise, Vaccination, and Sports Nutrition in the Course of Preparing Elite Athletes for the Management of Upper Respiratory Infections during the COVID-19 Pandemic: A Narrative Review

Elite athletes use high-intensity training to maintain their fitness level. However, intense training can harm the immune system, making athletes suspectable to COVID-19 and negatively affecting their performance. In addition, the diet of athletes should be appreciated more as it is another influencer of the immune system, especially during the COVID 19 pandemic. The other important issue elite athletes face currently is vaccination and its possible intervention with their training. The present study attempts to discuss the impact of different training intensities, nutritional strategies, and vaccination on the immune system function in elite athletes. To this end, Scopus, ISC, PubMed, Web of Science, and Google Scholar databases were searched from 1988 to 2021 using the related keywords. The results of our review showed that although high-intensity exercise can suppress the immune system, elite athletes should not stop training in the time of infection but use low- and moderate-intensity training. Moderate-intensity exercise can improve immune function and maintain physical fitness. In addition, it is also better for athletes not to undertake high-intensity training at the time of vaccination, but instead perform moderate to low-intensity training. Furthermore, nutritional strategies can be employed to improve immune function during high-intensity training periods.

Effects of exercise training on immunological factors in kidney transplant recipients; a randomized controlled trial

The purpose of this study was to investigate the effects of a 12 week exercise training on the immune system of kidney transplant recipients. 23 kidney transplant recipients were randomly divided into two groups including control (n = 10) and training (n =13) groups. The training groups participated in the training for 10 weeks (three days a week; each day 60-90 minutes). The control group performed no regular exercise during this time. The blood samples were taken before and after 12 weeks. ELISA and Real-time PCR were used to evaluate cytokine profiles, including TNF-a, IL-6, IL-4, IL-31 and IL-35 as well as T-bet, GATA-3, RORYt and FOXP3, respectively. Finally, the data were analyzed, using paired T-test. ELISA results showed decreased levels of TNF- α, increased levels of IL-6 and no significant differences in the IL-35, IL-31 and IL-4 levels in the training group in comparison to the control group. Gene expression profiles showed significantly increased expression of T-bet and no changes in the GATA-3, RORYt and FOXP3 levels. According to these results, a moderate exercise including aerobic and resistance training could inhibit inflammatory cytokines and have beneficial effects on the immune system, but this issue needs further research.

Intradialytic cycling does not exacerbate microparticles or circulating markers of systemic inflammation in haemodialysis patients

Purpose

Patients receiving haemodialysis (HD) display elevated circulating microparticle (MP) concentration, tissue factor (TF) expression and markers of systemic inflammation, though regular intradialytic cycling (IDC) may have a therapeutic effect. This study investigated the impact of regular, moderate-intensity IDC on circulating MPs and inflammatory markers in unit-based HD patients.

Methods

Patients were cluster-randomised to intervention (n = 20, age: 51.4 ± 18.1 years, body mass: 77.6 ± 18.3 kg, mean ± SD) or no-exercise control (n = 20, 56.8 ± 14.0 years, 80.5 ± 26.5 kg). Intervention participants completed 30 min of moderate intensity (rating of perceived exertion [RPE] of 12–14) IDC, thrice weekly for 6 months. Pre-dialysis venous blood samples were obtained at 0, 3 and 6 months. Circulating MP phenotypes, cytokines, chemokine and MP TF expression were quantified using flow cytometry and cytometric bead array assays.

Results

Despite high exercise compliance (82%), no IDC-dependent effects were observed for any MP, cytokine or chemokine measure (p ≥ 0.051, η_ρ² ≤ 0.399) other than TNF-α (p = 0.001, η_ρ² = 0.186), though no significance was revealed upon post hoc analysis.

Conclusion

Six months of regular, moderate-intensity IDC had no effect on MPs, cytokines or chemokines. This suggests that the exercise did not exacerbate thrombotic or inflammatory status, though further functional assays are required to confirm this.

Trial registration

ISRCTN1129707, prospectively registered on 05/03/2015.

The impact of intradialytic exercise on immune cells expressing CCR5+ in patients with chronic kidney disease: A cross-over trial

The C-C chemokine receptor type 5 (CCR5) plays a role in the immunopathogenesis of chronic kidney disease (CKD). Exercise has anti-inflammatory properties that may contribute to the rehabilitation of CKD patients. To date, the impact of the intradialytic exercise on CCR5 expression in monocytes and lymphocytes of CKD patients is unknown. We aimed to evaluate the effects of an acute intradialytic moderate-intensity exercise on CD4+CCR5+ T-cells and CD14+CCR5+ monocytes of elderly individuals with Chronic Kidney Disease (CKD). Eight CKD elderly patients performed a single bout of 20 min intradialytic exercise and a control hemodialysis (HD) session. Blood samples were collected at baseline, during and immediately after the trials. HD therapy increased the peripheral frequency of CD4+CCR5+ T-cells. The systemic CCL5 levels and the peripheral CD14+CCR5+ proportions increased during and after HD therapy. No significant alterations in CD4+CCR5+ and CD14+CCR5+ proportions or CCL5 levels were identified in CKD patients during and after intradialytic exercise. A negative correlation between the peripheral frequency of CD14+CCR5+ and the creatinine levels was identified in the intradialytic exercise session. A single moderate-intensity intradialytic exercise imposes an immunomodulatory impact in CKD elderly patients, preventing an excessive inflammatory response induced by hemodialysis.

Exercise and Circulating Microparticles in Healthy Subjects

This study aimed to explore the relationship between exercise and circulating microparticles (CMPs). PubMed, Web of Science, Embase, and the Cochrane Library databases were searched until August 13, 2020, using the terms "exercise" and "cell-derived microparticles." The Cochrane tool of risk of bias and the Methodological Index for Non-Randomized Studies were used to grade the studies. Twenty-six studies that met criteria were included in this review, including one before-after self-control study, 2 cohort studies, 4 randomized control trials, 5 case-control studies, and 14 descriptive studies. The studies were divided into a single bout and long-term exercise. The types of MPs contained endothelium-derived microparticles (EMPs), leukocyte-derived microparticles (LMPs), platelet-derived microparticles (PMPs), and erythrocyte-derived microparticles (ErMPs). This first systematic review found that the levels of CMPs continued to increase after a single bout of exercise in untrained subjects and were lower in trained subjects. PMPs expressed a transient increase after a single bout of exercise, and the proportion and duration of PMPs increment reduced in long-term exercise. Most studies showed a decline in LMPs in trained subjects after a single bout and long-term exercise, and variable changes were found in EMPs and ErMPs after exercise. A single bout of exercise drives the vessels exposed to high shear stress that promotes the formation of CMPs. However, the decline in CMPs in trained subjects may be attributed to the fact that they have a better ability to adapt to changes in hemodynamics and cellular function during exercise.