Sustained upregulation of inflammatory chemokine and its receptor in aneurysmal and occlusive atherosclerotic disease: results form tissue analysis with cDNA macroarray and real-time reverse transcriptional polymerase chain reaction methods.
BACKGROUND
Although cytokines are known to be pivotal in the development of atherosclerotic diseases, few data exist regarding their expressions in the established stages such as aneurysmal or occlusive lesions. Therefore, in the present study the gene expression levels of cytokine-related substances in abdominal aortic aneurysm (AAA) and carotid artery stenosis (CAS) were determined using cDNA macroarray and real-time reverse transcriptase polymerase chain reaction (RT-PCR) methods.


RESULTS
Tissue samples were obtained from 31 patients with AAA and 24 with CAS. The array-specific [33P]-labeled cDNA probe mixture synthesized from 2.5 microg total RNA with gene-specific primers was hybridized with nylon membranes containing 375 cDNA clones. Densitometric analysis confirmed differences in expression (>5-fold) for 97 of the cytokine-related gene products between AAA and adjacent control tissue. Among these, simultaneous upregulation was found in the expression of interleukin (IL)-8 (9-fold) and its receptor, CXCR-2 (11-fold). Thus, the expressions of IL-8 and CXCR-2 were further quantified by real-time RT-PCR. The expression of both the genes was significantly upregulated in both AAA and CAS compared with control regions as followed: IL-8=0.53+/-0.16 vs 0.11+/-0.04 (p<0.01); CXCR-2=2.04+/-0.75 vs 0.29+/-0.10 (p<0.01) in AAA, and IL-8=1.35 +/-0.25 vs 0.60+/-0.16; CXCR-2=2.00 +/-0.51 vs 0.58+/-0.21 (p<0.05) in CAS. Under these conditions, the gene expressions of monocyte chemotactic protein-1 and its receptor, CCR-2, were not significantly different in the control and diseased regions of both AAA and CAS.


CONCLUSIONS
Sustained upregulation of IL-8 and CXCR-2 was observed in both AAA and CAS, suggesting the inflammatory process is still active in established dilated and occlusive atherosclerotic diseases. Whether upregulation of this system could be protective or not protective for disease development requires further study.
Yamagishi
Masakazu
M
Division of Cardiovascular Medicine and Bioscience, National Cardiovascular Center and Research Institute, Suita, Japan. myamagi@hsp.ncvc.go.jp
Higashikata
Takeo
T
Ishibashi-Ueda
Hatsue
H
Sasaki
Hiroaki
H
Ogino
Hitoshi
H
Iihara
Koji
K
Miyamoto
Susumu
S
Nagaya
Noritoshi
N
Tomoike
Hitonobu
H
Sakamoto
Aiji
A
D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000276:immunology / Q000473:pathology; D001157:Arterial Occlusive Diseases / Q000276:immunology / Q000473:pathology; D001161:Arteriosclerosis / Q000276:immunology / Q000473:pathology*; D018925:Chemokines / Q000235:genetics*; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D006801:Humans; D007249:Inflammation / Q000235:genetics; D016209:Interleukin-8 / Q000235:genetics; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D019707:Receptors, Chemokine / Q000235:genetics*; D023063:Receptors, Interleukin-8B / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D046888:Tissue Array Analysis; D015854:Up-Regulation
D018925:Chemokines; D016209:Interleukin-8; D019707:Receptors, Chemokine; D023063:Receptors, Interleukin-8B