Induction of Cytokine Expression in Leukocytes in Acute Myocardial Infarction

Objectives. This study sought to investigate whether cytokine expression in leukocytes may be induced by plasm from the reperfused heart of patients with an acute myocardial infarction (MI). Background. Reperfusion in acute MI is associated with deleterious local and systemic inflammatory responses that are regulated by cytokines. Induction of cytokine expression in resident leukocytes could contribute to inflammatory responses of the ischemic and reperfused heart. Methods. Blood samples of 10 patients with an acute MI were obtained simultaneously from the coronary sinus and the aort before and 5 min after recanalization of the coronary occlusion. Ten patients with elective percutaneous transluminal coronary angioplasty served as control group. We incubated leukocytes from healthy donors with plasm samples and analyzed mRN expression of interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor-alph (TNF-alpha) by Northern blot analysis. Results. In patients with an acute MI, plasm obtained from the coronary sinus after recanalization increased the mRN expression of IL-1bet and IL-8 compared with that of plasm before recanalization (median [quartiles] difference before vs. after recanalization: 34.5 [4, 137], p = 0.017, for IL-1beta; 18.5 [4, 35], p = 0.032, for IL-8) and simultaneously obtained aortic plasm (median [quartiles] coronary sinus–aortic differences after recanalization: 45.5 [−3, 115], p = 0.021, for IL-1beta; 16 [4, 52], p = 0.005, for IL-8). No induction of IL-6 and TNF-alph expression could be observed. No changes found in the study patients were detectable in the control group. Conclusions. Plasm from the ischemic and reperfused heart stimulates the expression of IL-1bet and IL-8 in leukocytes. Therefore, leukocyte-derived cytokines may contribute to the regulation of cardiac inflammatory responses in patients with an acute MI.