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.

Does the Combined Effect of Resistance Training with EPO and Iron Sulfate Improve Iron Metabolism in Older Individuals with End-Stage Renal Disease?

We sought to investigate the effects of resistance training (RT) combined with erythropoietin (EPO) and iron sulfate on the hemoglobin, hepcidin, ferritin, iron status, and inflammatory profile in older individuals with end-stage renal disease (ESRD). ESRD patients (n: 157; age: 66.8 ± 3.6; body mass: 73 ± 15; body mass index: 27 ± 3), were assigned to control (CTL; n: 76) and exercise groups (RT; n: 81). The CTL group was divided according to the iron treatment received: without iron treatment (CTL-none; n = 19), treated only with iron sulfate or EPO (CTL-EPO or IRON; n = 19), and treated with both iron sulfate and EPO (CTL-EPO + IRON; n = 76). The RT group followed the same pattern: (RT-none; n = 20), (RT-EPO or IRON; n = 18), and (RT-EPO + IRON; n = 86). RT consisted of 24 weeks/3 days per week at moderate intensity of full-body resistance exercises prior to the hemodialysis section. The RT group, regardless of the iron treatment, improved iron metabolism in older individuals with ESRD. These results provide some clues on the effects of RT and its combination with EPO and iron sulfate in this population, highlighting RT as an important coadjutant in ESRD-iron deficiency.