MicroRNA molecules as predictive biomarkers of adaptive responses to strength training and physical inactivity in haemodialysis patients

Effect of muscle stretching and isometric exercises on quality of life in children undergoing regular hemodialysis

BACKGROUND

Chronic kidney disease (CKD) is a prevalent health issue that can have detrimental effects on the quality of life (QoL) of children. Nevertheless, with adequate management and support, many children with CKD can have satisfying lives. The study aimed to investigate the effect of muscle stretching and isometric exercises on QoL of children undergoing hemodialysis.

METHODS

Sixty-eight children aged 6-18 years with kidney failure undergoing hemodialysis at Assiut University Children Hospital were included. They were randomly assigned to two groups. The study group received a 40-min exercise program three times per week for 2 months, while the control group received routine hospital care. For outcome measures, two tools were used: a simple questionnaire sheet for personal and medical data and PedsQL™ scale.

RESULTS

After 2 months of exercise, it was shown that most children in the study group (66.7%) had good QoL, in contrast to only 3.3% in the control group, with a highly statistically significant variation between the two examined groups pertaining to the health-related QoL scale (P value = 0.001) after exercise.

CONCLUSION

The intensity of care for children on hemodialysis has a distinguished impact upon their quality of life. The implementation of muscle stretching and isometric exercises during hemodialysis represents an important aspect of such care that may be associated with significant improvement in all domains of QoL. Children undergoing hemodialysis need well-organized programs that cover all physical and psychological aspects with smart time manipulation and increased attention from their staff.

Hypoxia treatment and resistance training alters microRNA profiling in rats skeletal muscle

MicroRNAs (miRNAs) may play a crucial regulatory role in the process of muscle atrophy induced by high-altitude hypoxia and its amelioration through resistance training. However, research in this aspect is still lacking. Therefore, this study aimed to employ miRNA microarray analysis to investigate the expression profile of miRNAs in skeletal muscle from an animal model of hypoxia-induced muscle atrophy and resistance training aimed at mitigating muscle atrophy. The study utilized a simulated hypoxic environment (oxygen concentration at 11.2%) to induce muscle atrophy and established a rat model of resistance training using ladder climbing, with a total intervention period of 4 weeks. The miRNA expression profile revealed 9 differentially expressed miRNAs influenced by hypoxia (e.g., miR-341, miR-32-5p, miR-465-5p) and 14 differentially expressed miRNAs influenced by resistance training under hypoxic conditions (e.g., miR-338-5p, miR-203a-3p, miR-92b-3p) (∣log2(FC)∣ ≥ 1.5, p < 0.05). The differentially expressed miRNAs were found to target genes involved in muscle protein synthesis and degradation (such as Utrn, mdm2, eIF4E), biological processes (such as negative regulation of transcription from RNA polymerase II promoter, regulation of transcription, DNA-dependent), and signaling pathways (such as Wnt signaling pathway, MAPK signaling pathway, ubiquitin-mediated proteolysis, mTOR signaling pathway). This study provides a foundation for understanding and further exploring the molecular mechanisms underlying hypoxia-induced rats muscle atrophy and the mitigation of atrophy through resistance training.

Age and sex differences in the effectiveness of intradialytic resistance training on muscle function

Previous research shows the beneficial effects of an intradialytic resistance training (IRT) on muscle function in haemodialysis patients. However, patients vary highly in their functional responses to IRT, may be due to effects of age and sex heterogeneities in adaptation. Therefore, the aim of this study was to investigate the degree to which the effects of IRT on the muscle function of haemodialysis patients vary by age and sex. We included 57 patients who completed a 12-week IRT (EXG) and 33 patients who received no IRT (CNG) during haemodialysis. Muscle function (MF) was assessed using dynamometry before and after a 12-week intervention and after a 12-week follow-up. After the 12-week intervention, we found a moderation effect of age in the relative (%) change (p = 0.011) and absolute (Δ) change (p = 0.027) of MF, and a moderation effect of sex in %MF (p = 0.001), but not in ΔMF (p = 0.069). Regarding patients' age, the change of MF was only significantly different between EXG and CNG patients aged 60-70 years (%MF, EXG: + 34.6%, CNG: - 20.1%, p < 0.001; ΔMF, EXG: + 44.4 N, CNG: - 22.1 N, p < 0.001). Regarding patients' sex, the change of MF was only significantly different between EXG and CNG female patients (%MF, EXG: + 23.9%, CNG: - 23.6%, p < 0.001). Age and sex did not significantly moderate changes in MF measures after 12 weeks of follow-up. We conclude that both age and sex of haemodialysis patients affect their functional response to IRT in the short term.Trial Registration: Intradialytic Resistance Training in Haemodialysis Patients (IRTHEP)-#NCT03511924, 30/04/2018, https://clinicaltrials.gov/ct2/show/NCT03511924 .

MicroRNA levels in hemodialysis patients following resistance training: Associations with functional performance, inflammatory profile, sestrins-2, and nitric oxide

OBJECTIVE

Investigate the effects of long-term resistance training (RT) on expression of the four selected microRNAs (miRNA or mir) and further association with biomarkers related to functional performance in older end-stage renal disease (ESRD) patients undergoing hemodialysis.

METHODS

Twenty-five older hemodialysis patients (glomerular filtration rate <15 mL/min/1.73 m² aged 68.28 ± 1.06) were recruited for the study. Patients were allocated to two groups (control, n = 12 and RT, n = 13). The RT group completed 24 weeks of training, with sessions held three times per week on alternate days. Blood samples were collected pre- and post- intervention for miRNA and biochemical assays. Results were considered significant at P < 0.05.

RESULTS

RT promoted benefits in inflammatory profile, nitric oxide, sestrins-2, anthropometric data, and functional performance. Trained subjects presented a 51% decrease in miRNA-31 after intervention. In addition, miRNA-1 increased 128% after RT protocol. miRNA-1 significantly correlated with functional performance, inflammatory profile, sestrins-2, and nitric oxide (all P < 0.05).

CONCLUSIONS

These results suggest that the upregulation of miRNA-1 could be associated with physiological benefits promoted by RT in hemodialysis patients, providing novel understanding for potential regulatory miRNA effects on physiological RT response. These findings might point out to strategic direction for future studies.

Effects of intradialytic exercise for advanced-age patients undergoing hemodialysis: A randomized controlled trial

Previous reports have shown the benefits of intradialytic exercise to patients undergoing hemodialysis. However, most of those studies assessed the effects of exercise in middle-aged patients and little is known about advanced-age patients undergoing hemodialysis. Therefore, the present randomized controlled trial was performed to determine the effectiveness of exercise therapy in advanced-age patients undergoing hemodialysis. This non-blinded, randomized controlled parallel trial enrolled a total of 101 patients who were randomly assigned to intradialytic exercise (n = 51) or usual care (n = 50) groups. The training program included both resistance and aerobic exercises and was performed three times per week for 6 months. The aerobic exercise intensity was adjusted to a target Borg score of 13 for 20 minutes. Four types of resistance exercises were performed using elastic tubing, with three sets of 10 exercises performed at moderate intensity (13/20 on the Borg scale). The usual care group received standard care. Lower extremity muscle strength, Short Physical Performance Battery score, and 10-m walking speed were the outcomes and were evaluated before the hemodialysis session and after 6 months of training. There were statistically significant improvements in Short Physical Performance Battery score (effect size, 0.57; 95% confidence interval, 0.15‒1.95) in the exercise group relative to the control group. There were no statistically significant differences in lower extremity muscle strength or in the 10-m walking speed between the two groups. These findings suggest that 6 months of intradialytic training could improve physical function in older patients undergoing hemodialysis.

Investigating differential miRNA expression profiling using serum and urine specimens for detecting potential biomarkers for early prostate cancer diagnosis

Background/aim

MicroRNAs (miRNAs) are known up-to-date candidate biomarkers for several diseases. In addition, obtaining miRNA from different body fluids such as serum, plasma, saliva, and urine is relatively easy to handle. Herein we aimed to detect miRNAs as biomarkers for early stage prostate cancer (PC). For this purpose, we used urine and serum samples to detect any significant differences in miRNA profiles between patients and healthy controls.

Materials and methods

Total ribonucleic acid (RNA) in urine and serum samples were isolated from eight untreated PC patients, thirty healthy individuals were screened for miRNA profile, and candidate miRNAs were validated. Whole urinary and serum miRNA profile was analyzed using Affymetrix GeneChip miRNA 4.0 Arrays. Candidate miRNAs were investigated by stem-loop reverse transcription- polymerase chain reaction.

Results

When we analyzed the urinary samples of PC patients, 49 miRNAs were detected to be upregulated and 14 miRNAs were found to be downregulated when compared with healthy controls. According to the serum samples, 19 miRNAs were found to be upregulated, and 21 miRNAs were found to be downregulated when compared with healthy individuals as well. Interestingly, we detected only four overlapping miRNAs (MIR320A, MIR4535, MIR4706, MIR6750) that commonly increase or decrease in both serum and urine samples. Among them, MIR320A was found to be downregulated, and MIR4535, MIR4706, and MIR6750 were found to be upregulated for urine samples. However, only MIR6750 was upregulated and the other three miRNAs were downregulated for serum samples.

Conclusion

Notably, the expression profile of MIR320A was significantly altered in urine specimens of prostate cancer patients. We considered that MIR320A has been evaluated as a valuable biomarker that can be used in the early diagnosis of PC.

Selected In Situ Hybridization Methods: Principles and Application

We are experiencing rapid progress in all types of imaging techniques used in the detection of various numbers and types of mutation. In situ hybridization (ISH) is the primary technique for the discovery of mutation agents, which are presented in a variety of cells. The ability of DNA to complementary bind is one of the main principles in every method used in ISH. From the first use of in situ techniques, scientists paid attention to the improvement of the probe design and detection, to enhance the fluorescent signal intensity and inhibition of cross-hybrid presence. This article discusses the individual types and modifications, and is focused on explaining the principles and limitations of ISH division on different types of probes. The article describes a design of probes for individual types of in situ hybridization (ISH), as well as the gradual combination of several laboratory procedures to achieve the highest possible sensitivity and to prevent undesirable events accompanying hybridization. The article also informs about applications of the methodology, in practice and in research, to detect cell to cell communication and principles of gene silencing, process of oncogenesis, and many other unknown processes taking place in organisms at the DNA/RNA level.

The role of physical activity and miRNAs in the vascular aging and cardiac health of dialysis patients

Cardiovascular comorbidities are independent risk factors for mortality in dialysis patients. MicroRNA signaling has an important role in vascular aging and cardiac health, while physical activity is a primary nonpharmacologic treatment for cardiovascular comorbidities in dialysis patients. To identify the relationships between muscle function, miRNA signaling pathways, the presence of vascular calcifications and the severity of cardiovascular comorbidities, we initially enrolled 90 subjects on hemodialysis therapy and collected complete data from 46 subjects. A group of 26 subjects inactiv group (INC) was monitored during 12 weeks of physical inactivity and another group of 20 patients exercise group (EXC) was followed during 12 weeks of intradialytic, moderate intensity, resistance training intervention applied three times per week. In both groups, we assessed the expression levels of myo‐miRNAs, proteins, and muscle function (MF) before and after the 12‐week period. Data on the presence of vascular calcifications and the severity of cardiac comorbidities were collected from the patients’ EuCliD^® records. Using a full structural equitation modelling of the total study sample, we found that the higher the increase in MF was observed in patients, the higher the probability of a decrease in the expression of miR‐206 and TRIM63 and the lower severity of cardiac comorbidities. A reduced structural model in INC patients showed that the higher the decrease in MF, the higher the probability of the presence of calcifications and the higher severity of cardiac comorbidities. In EXC patients, we found that the higher the increase in MF, the lower the probability of higher severity of cardiovascular comorbidities.