Production of reactive oxygen species by monocyte-derived macrophages from blood of healthy donors and patients with ischemic heart disease

Abstract

Production of reactive oxygen species (ROS) by macrophages derived from blood monocytes of healthy donors (MPN) and patients with ischemic heart disease (IHD) (MPIHD) before, during, and after their incubation with low-density lipoprotein (LDL) isolated from blood plasma of healthy donors (LDLN) and patients with a high cholesterol level (LDLH) was investigated by the method of luminol-dependent (spontaneous) and stimulated chemiluminescence (CL) using opsonized zymosan (OZ) or phorbol-12-myristate-13-acetate (PMA) as the CL stimulators. It was shown that proper, luminol-dependent, and zymosan-or PMA-stimulated chemiluminescence of MPIHD was 1.4-, 1.8-, 2.7-, and 1.6-fold higher than the same types of chemiluminescence of MPN, respectively, (p<0.05–0.01). Although the effect of OZ on MPN and MPIHD was more potent than that of PMA (by 4.3- and 3.2-fold, respectively), but it appeared in 2.5–3.0 times slower than that of PMA. LDLN and LDLH incubated with MPN for the first 15 and 60 min caused the 1.4- and 2.5-increase of the luminol-dependent CL of MPN; the same treatment of MPIHD did not influence ROS production by these cells. Repeated increase in the OZ-stimulated CL of MPN was also observed after preincubation for 15–180 min with LDLN and LDLH followed by LDL removal, subsequent MPN washing and addition of Hanks solution and OZ; the repeated increase in OZ-stimulated CL of MPN was only observed after incubation with LDLH than with LDLN. No increase of CL was observed in experiments with MPIHD. Thus, more intensive chemiluminescence of macrophages obtained from blood of patients with IHD suggests their in vivo stimulation. LDLN and LDLH may cause both primary and secondary (after preincubation) stimulating effect on CL of MPN but not of MPIHD. Thus, the analysis of macrophage chemiluminescence is a sensitive test for evaluation the degree of macrophage stimulation; it may be effectively used for monitoring of effectiveness of medical treatment of patients.