Gómez-Hernández Almudena, Martín-Ventura Jose Luis, Sánchez-Galán Eva, Vidal Cristina, Ortego Mónica, Blanco-Colio Luis Miguel, Ortega Luis, Tuñón José, Egido Jesús
Vascular Research Laboratory, Fundación Jiménez Díaz, Avda Reyes Católicos 2, 28040 Madrid, Spain.
Atherosclerosis. 2006 Jul;187(1):139-49. doi: 10.1016/j.atherosclerosis.2005.08.035. Epub 2005 Oct 4.
Prostaglandin E2 (PGE(2), a product of the cyclooxygenase 2 (COX-2) and membrane-associated Prostaglandin E Synthase (mPGES-1) pathway, has been implicated in the instability of atherosclerotic plaques. We have studied COX-2, mPGES-1 and PGE2 receptors (EPs) expression in peripheral blood mononuclear cells (PBMC) and atherosclerotic plaques of 29 patients with carotid stenosis as well as the effect of different nuclear factor-kappaB (NF-kappaB) inhibitors on COX-2, mPGES-1 and EPs expression in cultured monocytic cells (THP-1).
COX-2, mPGES-1 and EP expression was analyzed by RT-PCR (PBMC), immunohistochemistry (plaques) and Western blot (THP-1). PGE2 levels were determined by ELISA (plasma and cell supernatants).
In relation to healthy controls, COX-2, mPGES-1 and EP-3/EP-4 mRNA expression was increased in PBMC from patients. In the inflammatory region of atherosclerotic plaques, an increase of COX-2, mPGES-1 and EPs expression was also observed. Activated NF-kappaB and COX-2, mPGES-1 and EPs proteins were colocalized in the plaque's cells. In cytokine-treated cultured THP-1, the NF-kappaB inhibitors parthenolide, Bay 11-7082 and PDTC reduced COX-2, mPGES-1 and EP-1/EP-3/EP-4 expression as well as PGE2 levels. By employing specific agonists and antagonists, we noted that the cytokine- and PGE2-induced metalloproteinase 9 (MMP-9) expression and activity occurs through EP-1/EP-3/EP-4, an effect downregulated by NF-kappaB inhibitors.
Patients with carotid atherosclerosis depict an overexpression of COX-2, mPGES-1 and EPs simultaneously in the PBMC as well as in the vulnerable region of plaques. The studies in cultured monocytic cells suggest that NF-kappaB inhibitors and/or EPs antagonists could represent a novel therapeutic approach to the treatment of plaque instability and rupture.
前列腺素E2（PGE2）是环氧化酶2（COX-2）和膜相关前列腺素E合酶（mPGES-1）途径的产物，与动脉粥样硬化斑块的不稳定性有关。我们研究了29例颈动脉狭窄患者外周血单核细胞（PBMC）和动脉粥样硬化斑块中COX-2、mPGES-1和PGE2受体（EPs）的表达，以及不同核因子-κB（NF-κB）抑制剂对培养的单核细胞（THP-1）中COX-2、mPGES-1和EPs表达的影响。
通过逆转录聚合酶链反应（RT-PCR，用于PBMC）、免疫组织化学（用于斑块）和蛋白质印迹法（用于THP-1）分析COX-2、mPGES-1和EP的表达。通过酶联免疫吸附测定法（ELISA，用于血浆和细胞上清液）测定PGE2水平。
与健康对照相比，患者PBMC中COX-2、mPGES-1和EP-3/EP-4 mRNA表达增加。在动脉粥样硬化斑块的炎症区域，也观察到COX-2、mPGES-1和EPs表达增加。活化的NF-κB与COX-2、mPGES-1和EPs蛋白在斑块细胞中共定位。在细胞因子处理的培养THP-1中，NF-κB抑制剂小白菊内酯、Bay 11-7082和吡咯烷二硫代氨基甲酸盐降低了COX-2、mPGES-1和EP-1/EP-3/EP-4的表达以及PGE2水平。通过使用特异性激动剂和拮抗剂，我们注意到细胞因子和PGE2诱导的金属蛋白酶9（MMP-9）表达和活性通过EP-1/EP-3/EP-4发生，NF-κB抑制剂可下调这种作用。
颈动脉粥样硬化患者的PBMC以及斑块的易损区域同时存在COX-2、mPGES-1和EPs的过表达。对培养的单核细胞的研究表明，NF-κB抑制剂和/或EPs拮抗剂可能是治疗斑块不稳定性和破裂的一种新的治疗方法。
