Acute Exercise-Induced Response of Monocyte Subtypes in Chronic Heart and Renal Failure

Purpose. Monocytes (Mon1-2-3) play a substantial role in low-grade inflammation associated with high cardiovascular morbidity andmortality of patients with chronic kidney disease (CKD) and chronic heart failure (CHF). Theeffect of an acute exercise bout on monocyte subsets in the setting of systemic inflammation is currently unknown. This study aims (1) to evaluate baseline distribution of monocyte subsets in CHF and CKD versus healthy subjects (HS) and (2) to evaluate the effect of an acute exercise bout. Exerciseinduced IL-6 and MCP-1 release are related to theMon1-2-3 response. Methods. Twenty CHF patients, 20 CKDpatients, and 15HS were included. Before and after a maximal cardiopulmonary exercise test, monocyte subsets were quantified by flow cytometry: CD14(++)CD16(-)CCR2(+) (Mon1), CD14(++)CD16(+)CCR2(+) (Mon2), and CD14(+)CD16(++)CCR2(-) (Mon3). Serum levels of IL-6 and MCP1 were determined by ELISA. Results. Baseline distribution of Mon1-2-3 was comparable between the 3 groups. Following acute exercise, % Mon2 and % Mon3 increased significantly at the expense of a decrease in % Mon1 in HS and in CKD. This response was significantly attenuated in CHF (beta < 0.05). In HS only, MCP-1 levels increased following exercise; IL-6 levels were unchanged. Circulatory power was a strong and independent predictor of the changes in Mon1 (beta = -0.461, P < 0.001) and Mon3 (beta = 0.449, P < 0.001); and baseline LVEF of the change in Mon2 (beta = 0.441, P < 0.001). Conclusion. The response of monocytes to acute exercise is characterized by an increase in proangiogenic and proinflammatory Mon2 and Mon3 at the expense of phagocytic Mon1. This exercise-induced monocyte subset response is mainly driven by hemodynamic changes and not by preexistent lowgrade inflammation.