Exp Mol Med.  2002 Dec;34(6):391-400.

Upregulation of extracellular matrix metalloproteinase inducer (EMMPRIN) and gelatinases in human atherosclerosis infected with Chlamydia pneumoniae: The potential role of Chlamydia pneumoniae infection in the progression of atherosclerosis

• Choi EY
• Kim DS
• Hong BK
• Kwon HM
• Song YG
• Byun KH
• Park HY
• Whang KC
• Kim HS

Abstract

Chlamydia pneumoniae infection implicated as an important etiologic factor of atherosclerosis, especially in coronary artery disease (CAD), was found in vitro to be associated with the induction of matrix metalloproteinases (MMPs). An extracellular matrix metalloproteinase inducer (EMMPRIN)/membrane-type 1 matrix metalloproteinase (MT1-MMP) system which induces and activates MMPs,is suggested to be functional and were upregulated in the failing myocardium. However, the upstream regulation of MMPs by C. pneumoniae within atheroma itself remains unclear. We evaluated the seroepidemiologic study of C. pneumoniae infection in CAD patients (n = 391) and controls (n = 97) and performed histopathological and in vitro analysis in atherosclerotic vascular tissues obtained from patients with seropositive to C. pneumoniae (n = 20), by using immunochemistry for C. pneumoniae, EMMPRIN/MT1-MMP, MMP-2, and MMP-9. The seropositive rates of both anti-C. pneumoniae IgG and IgA were 56.7% in CAD group and 43.3% in control group (P =0.033). Seropositive rate was increased in subgroups of CAD patients without conventional coronary risk factors compared to those with conventional risk factors. Immunoreactivities of EMMPRIN, MT1-MMP, MMP-2, and MMP-9 were increased in the atheromatous plaque itself, predominantly in immunoreactive macrophages/mononuclear cells to C. pneumoniae. Furthermore, Western blot analysis showed that EMMPRIN and MMP-2 were detected more prominently in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. Zymographic analysis revealed that activities of MMP-2 and MMP-9 were more increased in atherosclerotic tissues infected with C. pneumoniae compared to control tissues. The present study demonstrated upstream regulation of MMPs can be induced by C. pneumoniae within atheromatous plaque itself. These findings help to understand the potential role of C. pneumoniae in the progression of atherosclerosis.

Keyword

arteriosclerosis; chlamydia; enzyme induction; matrix metalloproteinases; tissue inhibitor of metalloproteinases

MeSH Terms

Aged
Animals
Arteriosclerosis/complications/enzymology/*microbiology/*pathology
Blotting, Western
Chlamydia Infections/*complications/enzymology/epidemiology/immunology
Chlamydophila pneumoniae/immunology/*pathogenicity
Disease Progression
Extracellular Matrix/enzymology
Female
Gelatinases/*metabolism
Human
Immunohistochemistry
Male
Matrix Metalloproteinases/*metabolism
Membrane Glycoproteins/*metabolism
Middle Aged
Up-Regulation