Danilo Takashi Aoike

Randomized controlled trial to evaluate the impact of aerobic exercise on visceral fat in overweight chronic kidney disease patients

BACKGROUND The prevalence of obesity has markedly increased in patients with chronic kidney disease (CKD). Studies on the impact of exercise focusing on obese CKD patients are scarce. Therefore, we aimed to investigate the effect of aerobic exercise performed either in an exercise centre or at home on visceral fat in overweight non-dialysed CKD patients. METHODS Twenty-seven sedentary men (52.1 ± 9.5 years, body mass index 30.4 ± 3.8 kg/m(2), estimated glomerular filtration rate (eGFR) 27.5 ± 11.6 mL/min) were randomly assigned to a centre-based exercise group (n = 10), home-based exercise group (n = 8) or control group (n = 9). The aerobic training was prescribed according to ventilatory threshold and performed three times per week during 12 weeks. Body composition was assessed by dual energy X-ray absorptiometry (DEXA) and the distribution of abdominal fat by computed tomography. RESULTS In the centre-based group, visceral fat and waist circumference decreased 6.4 ± 6.4 mm (P < 0.01) and 2.0 ± 2.3 cm (P = 0.03) and leg lean mass increased 0.5 ± 0.4 kg (P < 0.01). No significant changes were observed in the home-based group. Visceral fat increased 5.0 ± 4.4 mm in the control group (P = 0.01). In relation to the control, a group-by-time interaction was significant for visceral fat and waist circumference for both exercise groups and for leg lean mass for the centre-based group. Mean blood pressure decreased in both exercise groups (centre-based 13%, P < 0.01 and home-based 10%, P = 0.03) and eGFR increased 3.6 ± 4.6 mL/min (P = 0.03) in the centre-based group. These parameters remained unchanged in the control group. CONCLUSIONS Centre-based aerobic exercise is an effective approach to reduce visceral fat besides promoting relevant clinical benefits in male overweight CKD patients.

Impact of training at ventilatory threshold on cardiopulmonary and functional capacity in overweight patients with chronic kidney disease

INTRODUCTION Chronic kidney disease (CKD) and obesity are both associated with reduced physical capacity. The potential benefit of aerobic training on physical capacity has been recognized. The exercise intensity can be established using different methods mostly subjective or indirect. Ventilatory threshold (VT) is a direct and objective method that allows prescribing exercise intensity according to individual capacity. OBJECTIVES To evaluate the impact of aerobic training at VT intensity on cardiopulmonary and functional capacities in CKD patients with excess of body weight. METHODS Ten CKD patients (eight men, 49.7 ± 10.1 years; BMI 30.4 ± 3.5 kg/m², creatinine clearance 39.4 ± 9.8 mL/min/1.73 m²) underwent training on a treadmill three times per week during 12 weeks. Cardiopulmonary capacity (ergoespirometry), functional capacity and clinical parameters were evaluated. RESULTS At the end of 12 weeks, VO2PEAK increased by 20%, and the speed at VO2PEAK increased by 16%. The training resulted in improvement in functional capacity tests, such as six-minute walk test (9.2%), two-minute step test (20.3%), arm curl test (16.3%), sit and stand test (35.7%), and time up and go test (15.3%). In addition, a decrease in systolic and diastolic blood pressures was observed despite no change in body weight, sodium intake and antihypertensive medication. CONCLUSION Aerobic exercise performed at VT intensity improved cardipulmonary and functional capacities of overweight CKD patients. Additional benefit on blood pressure was observed. These results suggest that VT can be effectively applied for prescribing exercise intensity in this particular group of patients.

Cholecalciferol decreases inflammation and improves vitamin D regulatory enzymes in lymphocytes in the uremic environment: A randomized controlled pilot trial

It has been reported that vitamin D regulates the immune system. However, whether vitamin D repletion modulates inflammatory responses in lymphocytes from dialysis patients is unclear. In the clinical trial, thirty-two (32) dialysis patients with 25 vitamin D ≤ 20ng/mL were randomized to receive either supplementation of cholecalciferol 100,000 UI/week/3 months (16 patients) or placebo (16 patients). In the in vitro study, B and T lymphocytes from 12 healthy volunteers (HV) were incubated with or without uremic serum in the presence or absence of 25 or 1,25 vitamin D. We evaluated the intracellular expression of IL-6, IFN-γ TLR7, TLR9, VDR, CYP27b1 and CYP24a1 by flow cytometry. We observed a reduction in the expression of TLR7, TLR9, INF-γ and CYP24a1 and an increase in VDR and CYP27b1 expression in patients which were supplemented with cholecalciferol, whereas no differences were found in the placebo group. Uremic serum increased the intracellular expression of IL-6, IFN-γ, TLR7, TLR9, VDR, CYP27b1 and CYP24a1. Treatment with 25 or 1,25 vitamin D decreased IL-6 and TLR9. CYP24a1 silencing plus treatment with 25 and/or 1,25 vitamin D had an additional reduction effect on IL-6, IFN-γ, TLR7 and TLR9 expression. This is the first study showing that cholecalciferol repletion has an anti-inflammatory effect and improves vitamin D intracellular regulatory enzymes on lymphocytes from dialysis patients.