Effect of acute intradialytic strength physical exercise on oxidative stress and inflammatory responses in hemodialysis patients

Melatonin intake before intradialytic exercise reverses oxidative stress and improves antioxidant status in hemodialysis patients

PURPOSE

The present study aimed to investigate for the first time the effects of melatonin (MEL) intake on oxidative stress and cellular damage during intradialytic exercise (IEX).

METHODS

Thirteen hemodialysis (HD) patients volunteered to participate in the current randomized crossover trial. Participants performed four HD sessions in four different conditions: (Exercise (EX)-MEL), (EX-Placebo (PLA)), (Control (C)-MEL), and (C-PLA). 3 mg of MEL or PLA were taken 60 min before starting exercise, or at the equivalent time in the C conditions. Blood samples were taken before HD (T0), immediately after the end of IEX (T1), 60 min after IEX (T2), or at the corresponding times in the C conditions to measure free radicals damage, antioxidant biomarkers, as well as biomarkers of muscle and liver damage.

RESULTS

Malondialdehyde and Advanced Oxidation Protein Products decreased in (C-MEL) (p < 0.05, d = 2.19; p < 0.01, d = 0.99, respectively) at T2 compared to T0. Catalase and total thiol levels increased in (C-MEL) (p < 0.01, d = 1.51; p < 0.01, d = 1.56, respectively) and in (EX-MEL) (p = 0.01, d = 1.28; p < 0.01, d = 1.52, respectively) at T1 compared to T0. Total bilirubin levels increased in (EX-MEL) and (C-MEL) at T2 compared to T0 (p < 0.001, d = 2.77; p < 0.001, d = 1.36, respectively), but only at T2 compared to T1 in (EX-MEL) (p < 0.001, d = 1.67). In all conditions, uric acid levels decreased at T1 compared to T0 and at T2 compared to T1, while biomarkers of muscle and liver damage remained unchanged.

CONCLUSION

This pilot study is the first to show that MEL ingestion, alone or combined with IEX, could improve oxidant-antioxidant balance during HD.

Single 30 min treadmill exercise session suppresses the production of pro-inflammatory cytokines and oxidative stress in obese female adolescents

OBJECTIVES

Regular treadmill exercise may result in changes in pro-inflammatory cytokines and oxidative stress. However, the way acute treadmill exercise mechanisms affect the changes in pro-inflammatory cytokines and oxidative stress in obese has not been comprehensively exposed. This study aimed to analyze the pro-inflammatory cytokines and oxidative stress between 30 min before treadmill exercise and 24 h after treadmill exercise in obese adolescents.

METHODS

A total of 20 obese females aged 19-24 years were recruited from female students and given one session of treadmill exercise with an intensity of 60-70% HR_max. Thiobarbituric acid reactive substance (TBARS) was used to analyze serum levels of MDA, while enzyme-linked immunosorbent assay (ELISA) was used to analyze serum levels of TNF-α and IL-6. Moreover, the independent samples t-test with a significance level of 5% was employed to have the statistical analysis.

RESULTS

The results on 24 h after treadmill exercise and delta (Δ) between CTRL and TREG showed a significant difference (p<0.001).

CONCLUSIONS

This study found a decrease in pro-inflammatory cytokines and oxidative stress 24 h after treadmill exercise in obese adolescents. Therefore, treadmill exercise can be a promising strategy for preventing adolescents from obesity as well as preventing disease risks associated with oxidative stress and chronic inflammation.

Effect of Exercise on Inflammation in Hemodialysis Patients: A Systematic Review

Background: In recent years, physical exercise has been investigated for its potential as a therapeutic tool in patients with end-stage renal disease (ESRD) undergoing hemodialysis maintenance treatment (HD). It has been shown that regular practice of moderate-intensity exercise can improve certain aspects of immune function and exert anti-inflammatory effects, having been associated with low levels of pro-inflammatory cytokines and high levels of anti-inflammatory cytokines. Purpose: The aim of this review is to examine the studies carried out in this population that analyzed the effect of intradialytic exercise on the inflammatory state and evaluate which exercise modality is most effective. Methods: The search was carried out in the MEDLINE, CINAHL Web of Science and Cochrane Central Register of Controlled Trials databases from inception to June 2022. The PEDro scale was used to assess methodological quality, and the Cochrane Risk of Bias Tool and MINORS were used to evaluate the risk of bias. The quality of evidence was assessed with GRADE scale. The outcome measures were systemic inflammation biomarkers. Results: Mixed results were found in terms of improving inflammation biomarkers, such as CRP, IL-6 or TNFα, after exercise. Aerobic exercise seems to improve systemic inflammation when performed at medium intensity while resistance training produced better outcomes when performed at high intensity. However, some studies reported no differences after exercise and these results should be taken with caution. Conclusions: The low quality of the evidence suggests that aerobic and resistance exercise during HD treatment improves systemic inflammation biomarkers in patients with ESRD. In any case, interventions that increase physical activity in patients with ESRD are of vital importance as sedentary behaviors are associated with mortality. More studies are needed to affirm solid conclusions and to make intervention parameters, such as modality, dose, intensity or duration, sufficiently clear.

Aerobic Exercise Attenuates Kidney Injury, Improves Physical Performance, and Increases Antioxidant Defenses in Lungs of Adenine-Induced Chronic Kidney Disease Mice

The association between chronic kidney disease (CKD) and pulmonary pathophysiological changes is well stablished. Nevertheless, the effects of aerobic exercise (AE) on lungs of CKD need further clarification. Thus, Swiss mice were divided in control, AE, CKD, and CKD + AE groups. CKD was induced by 0.2% adenine intake during 8 weeks (4 weeks of CKD induction and 4 weeks of AE). AE consisted in running on treadmill, at moderate intensity, 30 min/day, 5 days/week, during 4 weeks. Twenty-four hours after the last training day, functional capacity test was performed, and 48 h after the test, mice were euthanized. CKD mice showed a significant increase in urine output, serum urea, and creatinine concentrations, and decreased body weight and urine density, besides oxidative damage (p = 0.044), edema area (p < 0.001), leukocyte infiltration (p = 0.040), and collagen area in lung tissue (p = 0.004). AE resulted in an increase of distance traveled (p = 0.049) and maximum speed (p = 0.046), increased activity of catalase (p = 0.031) and glutathione peroxidase (p = 0.048) in lungs, increased levels of nitric oxide (NOx) in serum (p = 0.001) and bronchoalveolar lavage fluid (p = 0.047), and decreased kidney histological injury (p = 0.018) of CKD mice. However, AE also increased oxidative damage (p = 0.003) and did not change collagen content or perivascular edema in lungs (p > 0.05) of CKD mice. Therefore, AE attenuated kidney injury and improved antioxidants defenses in lungs. Despite no significant changes in pulmonary damage, AE significantly improved physical performance in CKD mice.

Influence of Different Exercise Types on Health-Related Quality-of-Life in Men With Depressive Disorder in South Korea

The aim of the study was to determine the influence of different exercise types on health-related quality of life (QOL) in men with depressive disorder (DD) in South (S) Korea. The data of 385 men aged 19 with DD were collected in S. Korea. The Euro Quality of Life 5 Dimensions (EQ-5D) index and Korea National Health and Nutrition Examination Survey (KNHANES) questionnaires were used to establish the purpose of this study. Furthermore, the complex sampling model was applied to investigate the influence of different exercise types on health-related QOL in participants. When reviewing the outcomes, the strength exercise and walking had significant influences on health-related QOL in men with DD in S. Korea. However, the flexibility exercise did not have a significant influence on them. Based on the results, strength exercise and walking were effective exercise types to increase levels of health-related QOL in men with DD in S. Korea.

Effect of an aerobic and strength exercise combined program on oxidative stress and inflammatory biomarkers in patients undergoing hemodialysis: a single blind randomized controlled trial

BACKGROUND

Chronic kidney disease patients on hemodialysis treatment are characterized by increased levels of inflammatory markers and oxidative stress, in addition to a significant deterioration in physical function. The benefits of physical exercise on the functional capacity of this patients are well known; however, it can also improve the endogenous antioxidant defense system and the inflammatory state, but still very few studies have been carried out. This is the first study to analyze the effect of a 4-month exercise program with combined aerobic and strength training in patients undergoing hemodialysis, under two modalities.

METHODS

Seventy-one patients undergoing hemodialysis were enrolled and randomized in two groups, one of them performing an intra-dialysis exercise program (n = 36), and the other carrying out a home-based exercise program (n = 35). Serum levels of oxidative stress and inflammation biomarkers were determined before and after the intervention.

RESULTS

IL-6 plasma levels showed a significant decrease in the intra-dialysis group after exercise (42.61 ± 9.21 to 26.40 ± 7.84, p = 0.03), while CRP levels decreased significantly in the home-based group (16.12 ± 24.18 to 8.50 ± 11.28, p = 0.03). MCP-1, TNF-α, ICAM-1 and the oxidative stress markers MDA, GSH and GSSG, did not undergo significant changes after the intervention.

CONCLUSION

Four months of combined strength and aerobic endurance exercise improve the inflammatory status of hemodialysis patients by significantly reducing IL-6 levels in those subjects who perform intra-dialysis exercise and CRP levels in those who do it at home.

Effects of Different Types of Physical Activity on Health-Related Quality-of-Life in Korean Women with Depressive Disorder

Depressive disorder is a frequent psychological illness and causes community health problems for many women. It was found that the health-related quality of life (HRQoL) score of many women was altered due to mental and physical problems. Physical activity (PA) might effectively improve the responses of the HRQoL of women with depressive disorder. Therefore, the study aimed to identify the effects of different types of PA (e.g., walking, strength exercise, flexibility exercise) on the responses of the HRQoL of Korean women with depressive disorder. A sample of 1315 Korean women aged 19 or older with a depressive disorder was accumulated. The Korea National Health and Nutrition Examination Survey (KNHANES) and Euro Quality of Life-5 Dimensions (EQ-5D index score) were used. The characteristics of the participants were analyzed by the complex sample in frequency analysis. Furthermore, the complex sample general linear model was used to determine the effects of different types of PA on the HRQoL of Korean women with depressive disorder. In the results, there was a statistically significant difference between the groups who participated for one to two days, who participated for three to four days, and who did not participate in walking at all. In the flexibility exercise, there was a statistically significant difference in the group who participated for three to four days from the group who did not participate at all. However, there was no statistically significant difference in the strength exercise. In conclusion, the walking and flexibility exercises were effective physical activities (PAs) to improve the responses to the HRQoL of Korean women with depressive disorder.

The effect of a stress ball on stress, vital signs and patient comfort in hemodialysis patients: A randomized controlled trial

OBJECTIVE

In this study, an investigation was made of the effect of the use of a stress ball, a method of distraction-attracting the attention elsewhere - on stress, vital signs andcomfort levels in hemodialysis patients.

METHODS

This randomized, controlled experimental study, between July 2019 and September 2019 was carried out in a dialysis unit in the inner regions of Turkey. The study was conducted with 45 patients (23 experiments, 22 controls) who were receiving hemodialysis treatment. The experimental group were asked to squeeze a stress ball for approximately 10-15 min throughout eight successive dialysis sessions. The data were obtained with an Individual Description Form, the Distress Thermometer and the Hemodialysis Comfort Scale.

RESULTS

At the end of the study, no significant difference was found in the vital signs and comfort levels of the experimental and control groups (p > 0.05). However, while the stress score of the experimental group decreased significantly, the stress score of the control groups increased (p < 0.05).

CONCLUSION

This study shows that although the use of the stress ball did not affect vital signs and comfort in hemodialysis patients, it had a positive effect on stress.

Beneficios del ejercicio físico en la sesión de hemodiálisis. Una revisión sistemática

Objetivo: El objetivo principal de esta revisión fue conocer los principales beneficios del ejercicio físico durante la sesión de diálisis, en los pacientes en programa de hemodiálisis periódicas.Material y Método: Se llevó a cabo una revisión sistemática a través de las bases de datos Pubmed, Science Direct y Google Académico. Se incluyeron artículos científicos en inglés y español, y se analizaron los artículos que trataban sobre ejercicio físico en la sesión de hemodiálisis. Se excluyeron aquellos artículos que no presentaran resultados y en los que el ejercicio físico fuese domiciliario.Resultados: Se incluyeron 18 artículos publicados entre 2015 y 2019. Todos los artículos fueron de diseño experimental. Se encontró una mejoría significativa de la fuerza muscular, al igual que de la capacidad física y de de la sintomatología depresiva. En menor medida, se observó una disminución de la presión arterial, disminución del proceso inflamatorio, mejoría de los valores nutricionales y mejora de la calidad de vida de estos pacientes.Conclusiones: El ejercicio físico en la sesión de hemodiálisis tiene beneficios para la salud de los pacientes. El ejercicio físico de baja intensidad, así como la electroestimulación neuromuscular en las sesiones de diálisis, mejora objetivamente la fuerza muscular, aumenta la capacidad física, mejora la sintomatología depresiva con un mejor manejo del estrés y la ansiedad. Además, perece que puede mejorar el proceso inflamatorio, parámetros nutricionales y disminuir la presión arterial, así como mejorar la calidad de vida. La electroestimulación neuromuscular y el ejercicio físico de baja intensidad, son los ejercicios más utilizados.

Intradialytic Cardiovascular Exercise Training Alters Redox Status, Reduces Inflammation and Improves Physical Performance in Patients with Chronic Kidney Disease

Redox status (RS) perturbations and inflammation are fundamental features of chronic kidney disease (CKD) that are substantially exacerbated in end-stage renal disease (ESRD). This study aimed at investigating the efficacy of a 6-month intradialytic exercise training program on RS, inflammation and physical performance in patients with ESRD. Twenty hemodialysis (HD) patients (17 males, three females) were randomly assigned to either an intradialytic training (bedside cycling) group (TR; n = 10) or a control group (CON; n = 10) for 6 months. Anthropometrics [body mass and height, body mass index (BMI), body composition], physical performance (VO_2peak), functional capacity [North Staffordshire Royal Infirmary (NSRI) walk test, sit-to-stand test (STS-60)], quality of life (short form-36 (SF-36) as well as RS [thiobarbituric acid reactive substances (TBARS), protein carbonyls (PC), reduced (GSH) and oxidized (GSSG) glutathione, GSH/GSSG, total antioxidant capacity (TAC), catalase activity (CAT)] and high-sensitivity C-reactive protein (hs-CRP) were assessed at baseline and after the 6-month intervention. Peak oxygen consumption (VO_2peak) increased by 15% only in TR (p < 0.01). Performance in NSRI, STS-60 and SF-36 improved by 4–13% only in TR (p < 0.01). Exercise training reduced TBARS (by 28%), PC (by 31%) and hs-CRP (by 15%), and elevated GSH (by 52%), GSH/GSSG (by 51%), TAC (by 59%) and CAT (by 15%) (p < 0.01). These findings suggest that engagement in chronic intradialytic cardiovascular exercise alters RS, reduces inflammation and improves performance in patients with ESRD.

Effects of Physical Activity on the Stress and Suicidal Ideation in Korean Adult Women with Depressive Disorder

Depressive disorder is common in many adult women in the world. It was found that depressive disorder was related to stress and suicidal ideation in Korean adult women with depressive disorder. Physical activities were effective to solve this mental disorder. Thus, the purpose of the study was to investigate the effects of physical activity (PA) on the stress and suicidal ideation of Korean adult women with depressive disorder. A sample of 1315 Korean adult women who have depressive disorder was collected, and the Korea National Health and Nutrition Examination Survey (KNHANES) was used to determine this purpose of the study. The complex samples in frequency analysis were used to identify the characteristics of the participants. The logistic regression in the complex sample design was conducted to investigate the effects of PA on the stress and suicidal ideation in Korean adult women with depressive disorder. The effects of flexibility exercise on the stress in Korean adult women with depressive disorder showed the odds ratio (OR) value of 1.434 (OR = 1.434, 95% CI = 1.043–1.973, p < 0.05). The effects of flexibility exercise on the suicidal ideation in Korean adult women with depressive disorder presented the OR value of 0.682 (OR = 0.682, 95% CI = 0.496–0.937, p < 0.05). Based on the results, the participants who did flexibility exercises were likely to have less stress and suicidal ideation than the Korean adult women with depressive disorder who did not participate in flexibility exercise. In conclusion, the flexibility exercise has played an important role in reducing and preventing stress and suicidal ideation in Korean adult women with depressive disorder.

Exercise-Induced Regulation of Redox Status in Cardiovascular Diseases: The Role of Exercise Training and Detraining

Although low levels of reactive oxygen species (ROS) are beneficial for the organism ensuring normal cell and vascular function, the overproduction of ROS and increased oxidative stress levels play a significant role in the onset and progression of cardiovascular diseases (CVDs). This paper aims at providing a thorough review of the available literature investigating the effects of acute and chronic exercise training and detraining on redox regulation, in the context of CVDs. An acute bout of either cardiovascular or resistance exercise training induces a transient oxidative stress and inflammatory response accompanied by reduced antioxidant capacity and enhanced oxidative damage. There is evidence showing that these responses to exercise are proportional to exercise intensity and inversely related to an individual’s physical conditioning status. However, when chronically performed, both types of exercise amplify the antioxidant defense mechanism, reduce oxidative stress and preserve redox status. On the other hand, detraining results in maladaptations within a time-frame that depends on the exercise training intensity and mode, as high-intensity training is superior to low-intensity and resistance training is superior to cardiovascular training in preserving exercise-induced adaptations during detraining periods. Collectively, these findings suggest that exercise training, either cardiovascular or resistance or even a combination of them, is a promising, safe and efficient tool in the prevention and treatment of CVDs.

Clinical Significance of Postoperative Nutritional Status as a Prognostic Factor in Kidney Transplant Recipients

BACKGROUND

Despite advancements in the management of kidney transplantation (KT), kidney transplant recipients (KTRs) have a higher risk of mortality than the age-matched general population. Improvement of long-term graft and patient survival is a significant issue. Therefore we investigated the effects of postoperative nutritional status on graft and patient survival and explored the predictive factors involved in nutritional status.

METHODS

Our retrospective study included 118 KTRs who underwent KT at our hospital. Clinical and laboratory data were obtained from medical charts. The prognostic nutritional index (PNI) was used to assess nutritional status. Changes in nutritional status after KT were monitored and the effect of nutritional status on graft and patient survival was investigated. The variables involved in nutritional status were also explored.

RESULTS

The KTRs in this cohort comprised 66 men and 52 women with a median age of 47 years at KT. There were 16, 32, and 22 cases of cadaveric, preemptive, and ABO-incompatible KTs, respectively. Postoperative PNI gradually improved and was stable from 6 months after KT. Although graft survival was regulated by ABO-compatibility, independent predictors for patient survival were history of dialysis, PNI, and serum-corrected calcium levels. Preemptive KT and inflammatory status contributed to PNI.

CONCLUSIONS

Nutritional status of KTRs improved over time after KT and could contribute to patient survival. Optimal nutritional educational programs and interventions can lead to better outcomes in KTRs. Further studies are needed to validate our results and develop appropriate nutritional educational programs, interventions, and exercise programs.

Intradialytic exercise improves physical function and reduces intradialytic hypotension and depression in hemodialysis patients

BACKGROUND/AIMS

As numbers of maintenance hemodialysis patients are growing, debilitating conditions of muscle wasting and atrophy are becoming some of the greatest concerns in end-stage renal disease patients. Exercise training has various potential benefits in terms of prevention of a sustained decline in functional status. This study aimed to evaluate the physical, psychological, laboratory, and dialysis-related effects of intradialytic exercise.

METHODS

We enrolled 22 patients from a hemodialysis center for a 6-month non-randomized prospective trial. Combination of aerobic exercise with bicycle ergometer and anaerobic exercise with elastic bands was conducted during hemodialysis. Data including physical fitness test results, dialysis-related measurements, and biochemical laboratory results were collected at baseline, 3, and 6 months. Depression and quality of life were assessed using Beck Depression Inventory and Short Form-36 health survey.

RESULTS

After exercise completion, there were significant improvements in back muscle power, forward and backward trunk flexibility, vertical jump, elbow flexion, sit to stand test, and 6-minute walk test (p < 0.05). No significant changes were observed in dry weight, blood pressure, Kt/V, and biochemical variables, except for intradialytic hypotension (p < 0.05). For depression, Beck Depression Inventory showed statistically significant enhancement (p < 0.05). Scores of Short Form-36 health survey did not show significant increase in each domain, except for bodily pain (p < 0.05).

CONCLUSION

Combined aerobic and anaerobic exercise training during dialysis was found to be effective on physical health status, intradialytic hypotension, and depression in terms of mental health. Therefore, the findings of the current study may provide an appropriate guidance for encouraging exercise by nephrologists.

The effects of intradialytic resistance training on muscle strength, psychological well-being, clinical outcomes and circulatory micro-ribonucleic acid profiles in haemodialysis patients: Protocol for a quasi-experimental study

BACKGROUND

Intradialytic resistance training (IRT) protects patients' muscle mass and functions against protein-energy wasting, malnutrition and cachexia. However, the evidence of the effects of such an intervention in haemodialysis patients is limited and not conclusive. To improve the applicability of such interventions, we need a better understanding of molecular, functional and psycho-social adaptation in dialysed patients following a physical training. Therefore, the aim of this study is to investigate the effects of IRT on lower extremity muscle functions, quality of life, and anxiety and depression, clinical outcomes and circulatory micro-ribonucleic acid (miRNA) profiles in patients on chronic haemodialysis therapy.

METHODS

We will perform a quasi-experimental study in 3 dialysis centres. Patients will be recruited via their nephrologists and will be allocated to an experimental and a control group based on the location of the patients' dialysis centre. Patients allocated to the experimental group will undergo a 12-week IRT, while the control group will remain physically inactive during dialysis. The primary outcome is the change in the maximal force produced during an isometric contraction of lower extremity muscles. Secondary outcomes regard quality of life, anxiety and depression, clinical outcomes and circulatory miRNA profiles. Patients' level of health literacy defined as the ability to get and understand health information will be also measured in the study as a potential modifier of effects.

DISCUSSION

This quasi-experimental study can add in an important way to our understanding of the effects of resistance training on dialysis patients' muscle strength, quality of life and disease-specific outcomes.

Preventive effect of exercise training on diabetic kidney disease in ovariectomized rats with type 1 diabetes

IMPACT STATEMENT

To date, no studies have been found evaluating the effects of physical exercise on renal function and structure changes in ovariectomized rats with type 1 diabetes. Therefore, this work emerges with an important tool for strengthening and expanding innovative research on exercise with potential for the prevention of renal diseases in ovariectomized diabetic rats, and future development of studies that seek to increase scientific knowledge about the beneficial effects of physical exercise on renal diseases in humans.

Apple intake improves antioxidant parameters in hemodialysis patients without affecting serum potassium levels

Oxidative stress (OS) is associated with increased morbidity and mortality in hemodialysis (HD) patients, and the consumption of fruits seems to improve OS due to their antioxidant properties. Therefore, we hypothesized that Fuji apple intake improves OS markers in HD patients due to its polyphenolic compounds without increasing serum potassium levels. This trial was a 1-group, pre- and posttest comparison between 16 patients who had been on hemodialysis for at least 3 months without any acute illness or hyperkalemia. Each volunteer consumed 2 Fuji apples (~360 g) per day for 1 week. Blood samples were collected at the baseline period and after 8 days for the measurement of total antioxidant status, ascorbic acid, catalase, glutathione peroxidase, superoxide dismutase, reduced glutathione, total oxidant status, oxidative stress index, potassium, phosphorus, uric acid, glucose, and fructosamine. For tolerance evaluation, participants were asked about their bowel habits. Apple intake increased glutathione peroxidase (P = .006) and superoxide dismutase activities (P = .006) and ascorbic acid levels (P = .002). No significant changes were observed in uric acid, potassium, phosphorus, glucose, and fructosamine levels. Additionally, there was a decrease in the catalase activity (P = .021) and in the total antioxidant status values (P = .004). However, increased total oxidant status (P = .003) and oxidative stress index (P = .033) levels were observed after apple intake. In conclusion, the intake of 2 Fuji apples per day for 1 week was well tolerated and improved antioxidant parameters in HD patients without affecting serum potassium levels.

Does high intensity exercise affects irisin plasma levels in hemodialysis patients? A pilot study

BACKGROUND

Irisin is a recently identified exercise-induced hormone that stimulates the "browning" of the white adipose tissue, at least in mice. In chronic kidney disease (CKD) patients, irisin regulation is not fully understood, and little attention has been given to the effects of exercise on irisin levels in these patients. The purpose of this study was to assess the effects of high intensity exercise on irisin plasma levels in CKD patients under hemodialysis (HD).

METHODS

Fifteen HD patients (5 men, 44.4 ± 15.1 years old) were studied and served as their own controls. High intensity (single session) intradialytic strength exercises consisted of three sets of ten repetitions with four different movements in both lower limbs during 30 minutes. Blood samples were collected on different days (exercise and non-exercise day) at exactly the same time (30 and 60 minutes after the start of dialysis session). Plasma irisin levels were measured by ELISA assay and anthropometric and biochemical parameters were evaluated.

RESULTS

Irisin plasma levels were significantly reduced in both exercise day (125.0 ± 18.5 to 117.4 ± 15.0 ng/mL, p=0.02) and non-exercise day (121.5 ± 13.7 to 115.4 ± 17.2 ng/mL, p=0.02) after 60 minutes of dialysis.

CONCLUSION

These data suggest that intense intradialytic strength exercise was unable to increase the circulating concentration of irisin in HD patients. Moreover, our data show that after one hour of dialysis session, irisin plasma levels may be reduced.

Does resistance exercise performed during dialysis modulate Nrf2 and NF-κB in patients with chronic kidney disease?

Studies have shown that nuclear factor erythroid 2-related factor 2 (Nrf2) can be modulated by physical exercise. However, the impact of resistance exercise has never been investigated in patients with chronic kidney disease (CKD). The aim of this study was to evaluate the effects of resistance exercise programs on the expression of transcription factors Nrf2 and nuclear factor κB (NF-κB) in CKD patients on hemodialysis (HD). Patients on an HD program were randomly assigned to an exercise group of 25 patients (54.5% women, aged 45.7±15.2years and time on dialysis=71.2±45.5months) or a control group of 19 patients who had no exercise intervention (61.5% women, aged 42.5±13.5years and time on dialysis=70.1±49.9months). A strength exercise program was performed 3 times a week during the HD sessions. Peripheral blood mononuclear cells were isolated and processed for the expression of Nrf2 and NF-κB by quantitative real-time polymerase chain reaction 3months before and after the exercise program. Using an enzyme-linked immunosorbent assay, the activity of glutathione peroxidase (GPx) as well as the products of high-sensitivity C-reactive protein and nitric oxide (NO) were assessed. Nrf2 expression (ranging from 0.86±0.4 to 1.76±0.8) and GPx activity were significantly increased after exercise intervention. In the exercise group, no difference in the levels of NO was observed; however, there was a significant reduction in the control group. In conclusion, these data suggest that resistance exercises seem to be capable of inducing Nrf2 activation in CKD patients on HD.

The Effect of Intra-Dialytic Exercise on Inflammation and Blood Endotoxin Levels

Background: In healthy individuals, an acute inflammatory response occurs after intense exercise due to gut ischaemia and intestinal bacterial endotoxin translocation into the bloodstream. This process maybe exacerbated in patients who exercise during dialysis due to large volume shifts experienced by many during haemodialysis (HD). The acute effect of intra-dialytic exercise on blood endotoxins and inflammation is not known. Method: The effect of intra-dialytic exercise on blood endotoxin and inflammation was investigated in 10 patients and compared with resting haemodialysis. Blood was measured for endotoxin and inflammatory biomarkers before and after dialysis. Result: With the exception of one sample, all samples tested negative for endotoxin. Intra-dialytic exercise attenuated the rise of interleukin-6, tumour necrosis factor-α and high-sensitivity C-reactive protein after the HD procedure. Conclusion: Intra-dialytic exercise was not associated with an observable rise in blood endotoxin, although it may ameliorate the inflammatory effects of the HD procedure. Larger studies are needed to confirm this finding.

Correlation between Inflammatory Biomarkers and Red Blood Cell Life Span in Chronic Hemodialysis Patients

Background and Objectives: The pathogenesis of anemia in hemodialysis (HD) patients is dependent on multiple factors, with decreased red blood cell life span (RBCLS) being a significant contributor. Although the impact of reduced RBCLS on anemia is recognized, it is still a subject that is not well researched. The objective of this study was to investigate the relationship between RBCLS and inflammatory biomarkers in chronic HD patients. Design, Setting, Participants, and Measurements: RBCLS was calculated from alveolar carbon monoxide concentrations measured by gas chromatography. Interleukins (IL) IL-6, IL-18, IL-10, and high sensitivity C-reactive protein were measured using bead-based multiplex assay. Measurements were carried out at baseline and during follow-up. The associations between RBCLS and inflammatory biomarkers were evaluated using linear mixed effects models. Results: RBCLS measurements were available for 54 HD patients. Their average age was 58.5 ± 14.4 years, 68.5% were males, 48.1% were diabetics, and the HD vintage was 51 ± 48 months. In 4 patients, RBCLS was measured once, while in 50 patients, up to 5 repeated RBCLS measurements were available. RBCLS was 73.2 ± 17.8 days (range 37.7-115.8 days). No association was found between RBCLS and any of the inflammatory biomarkers. Of note, RBCLS was positively correlated with levels of uric acid (p = 0.02) and blood urea nitrogen (BUN; p = 0.01), respectively. Conclusion: Our study suggests that inflammation pathways reported by these biomarkers only have a limited role in causing premature RBC death. The positive correlation with uric acid and BUN warrants further studies.

The Impact of Exercising During Haemodialysis on Blood Pressure, Markers of Cardiac Injury and Systemic Inflammation--Preliminary Results of a Pilot Study

BACKGROUND/AIMS

Patients requiring haemodialysis have cardiovascular and immune dysfunction. Little is known about the acute effects of exercise during haemodialysis. Exercise has numerous health benefits but in other populations has a profound impact upon blood pressure, inflammation and immune function; therefore having the potential to exacerbate cardiovascular and immune dysfunction in this vulnerable population.

METHODS

Fifteen patients took part in a randomised-crossover study investigating the effect of a 30-min bout of exercise during haemodialysis compared to resting haemodialysis. We assessed blood pressure, plasma markers of cardiac injury and systemic inflammation and neutrophil degranulation.

RESULTS

Exercise increased blood pressure immediately post-exercise; however, 1 hour after exercise blood pressure was lower than resting levels (106±22 vs. 117±25 mm Hg). No differences in h-FABP, cTnI, myoglobin or CKMB were observed between trial arms. Exercise did not alter circulating concentrations of IL-6, TNF-α or IL-1ra nor clearly suppress neutrophil function.

CONCLUSIONS

This study demonstrates fluctuations in blood pressure during haemodialysis in response to exercise. However, since the fall in blood pressure occurred without evidence of cardiac injury, we regard it as a normal response to exercise superimposed onto the haemodynamic response to haemodialysis. Importantly, exercise did not exacerbate systemic inflammation or immune dysfunction; intradialytic exercise was well tolerated.