T-cell profile and systemic cytokine levels in overweight-obese patients with moderate to very-severe COPD.

This study aimed to evaluate the immune profile of lean and overweight-obese COPD patients. Forty patients with moderate to very severe COPD were divided into lean group (n=20; aged 62.00±8.91years; BMI 22.26±1.65kg/m2) or overweight-obese group (n=20; aged 65.40±6.69years; BMI 29.19±3.55kg/m2). The cytokine profile (IL-2, IL-4, IL-6, IL-10, INF-γ, and TNF-α) was evaluated through the Cytometric Bead Array technique, and the expression of CD4, CD8, CD25, CD45ra, CD45ro, CD69, CD195(CCr5) and HLA-DR were evaluated in CD3+ T-cells. Overweight-obese COPD group had lower levels of IL-2 (p=0.01) and higher INF-γ levels (p=0.02) and IL-6 (p=0.003) than lean COPD. Lean COPD patients had higher CD25+ (p=0.01), CCr5 (p=0.04) and HLA-DR (p=0.007) expression on T cell surface compared to overweight-obese COPD participants. These changes are related to immune dysfunction of obesity, and excess of fat mass in COPD can be a key factor to low T-cells activation.

Acute exercise during hemodialysis prevents the decrease in natural killer cells in patients with chronic kidney disease: a pilot study.

PURPOSE: To evaluate the acute response of natural killer (NK) cell subsets of chronic kidney disease patients submitted to intradialytic exercise in a randomized crossover study. METHODS: Nine patients were submitted to a single bout of 20-min intradialytic exercise and a control hemodialysis (HD) session with an interval of 7 days between them. Peripheral blood sample was collected at baseline, during HD and immediately after HD in each trial to evaluate the peripheral frequency of NK cells and their subsets (CD3-CD56bright and CD3-CD56dim), systemic cortisol concentrations, C-reactive protein (CRP), creatine kinase activity (CK), and urea and creatinine levels. RESULTS: HD therapy induced a significant decrease in NK cells frequency (p = 0.039), NK CD3-CD56bright cells (p = 0.04), and CD3-CD56dim cells (p = 0.036). On the other hand, no significant alterations were observed in NK cells and NK subsets during and after intradialytic exercise trial (p > 0.05). Neither trial altered CRP levels or serum CK activity during and after HD therapy (p > 0.05). However, HD therapy increased cortisol concentrations after HD therapy (p = 0.034). CONCLUSIONS: This study suggests the potential role of intradialytic exercise to prevent the decrease in peripheral frequency of NK cell subsets during HD therapy. Moreover, moderate intensity intradialytic exercise did not exacerbate the systemic inflammation or induce muscle damage during HD therapy.

Effects of Expiratory Positive Airway Pressure on Exercise Tolerance, Dynamic Hyperinflation, and Dyspnea in COPD.

INTRODUCTION: The application of expiratory positive airway pressure (EPAP) in patients with COPD during exercise may reduce dynamic hyperinflation, while, on the other hand, it can increase the resistive work of breathing. Therefore, we evaluated the effects of 2 intensities of EPAP during exercise on tolerance, dynamic hyperinflation, and dyspnea in subjects with moderate to very severe COPD. METHODS: We performed a cross-sectional, experimental, 4-visit study. In visit 1, subjects performed symptom-limited cycling incremental cardiopulmonary exercise test (CPET). In visits 2-4, at least 48 h apart, in a randomized order, subjects performed constant CPET without EPAP, EPAP with 5 cm H2O (EPAP5), or EPAP with 10 cm H2O (EPAP10). RESULTS: The study included 15 non-hypoxemic subjects ranging from moderate to very severe COPD (mean FEV1 = 35 ± 11% predicted). Increasing intensities of EPAP during constant CPET tended to cause progressive reduction in exercise tolerance (P = .11). Of note, 10 of 15 subjects demonstrated significantly shorter average exercise duration with EPAP10 compared to the test without EPAP (-151 ± 105 s, P = .03 or -41 ± 26%). Minute ventilation increment was constrained by EPAP, secondary to a limited increase in tidal volume (P = .01). Finally, dyspnea sensation and serial measurements of inspiratory capacity during exercise were similar when comparing the three interventions at isotime and at end-constant CPETs. CONCLUSIONS: The application of EPAP5 or EPAP10 during exercise tended to cause a progressive reduction in exercise tolerance in subjects with COPD without improvement in dyspnea or dynamic hyperinflation at equivalent exercise duration.