Expression of CCL2 signaling pathway genes in patients with periodontitis and atherosclerosis.

Objective: Periodontitis and atherosclerosis are chronic inflammatory diseases characterized by leukocyte infiltration. We investigated the expression of CCL4, CCR5, c-Jun, c-Fos, NF-κB, and CCL2 as well as the possible mechanism involved in the regulation of CCL2 in human periodontitis tissues and atherosclerotic aorta based on previous research on the CCL4/CCR5/c-Jun and c-Fos/CCL2 pathway leading to CCL2 expression in collagen-induced arthritis (CIA) rat.

Methods: Sixty-five volunteers were recruited and the condition of their gingiva and coronary arteries were assessed. The subjects were divided into four groups: healthy control, chronic periodontitis (CP), coronary artery diseases (CAD), and noncoronary artery diseases (non-CAD). Total RNA was isolated from gingiva in periodontitis patients and control populations and from the aorta in patients with and without CAD. PCR was used to examine CCL4, CCR5, c-Jun, c-Fos, NF-κB, and CCL2 levels. The production of CCL2 in the gingiva and aorta was analyzed by immunostaining.

Results: PCR revealed that CCL4, CCR5, and CCL2 mRNA levels were increased in CP patients' gingivae and aortas from coronary artery bypass grafting (CABG) patients. Marked c-Jun, c-Fos, and NF-κB gene productions were detected in CP patients' gingivae but did not show statistical differences between the CAD and non-CAD groups. Stronger immunoreactivity against CCL2 was observed in periodontitis gingiva and aorta from CABG patients.

Conclusions: Our findings suggest that the CCL4/CCR5/c-Jun and c-Fos/CCL2 pathways may be involved in CCL2 expression in periodontitis. CCL4, CCR5, and CCL2 might act as possible nodes to link the presence of periodontitis and atherosclerosis.