Reiss Allison B, Carsons Steven E, Anwar Kamran, Rao Soumya, Edelman Sari D, Zhang Hongwei, Fernandez Patricia, Cronstein Bruce N, Chan Edwin S L
Vascular Biology Institute, Winthrop-University Hospital, Mineola, New York 11501, USA.
Arthritis Rheum. 2008 Dec;58(12):3675-83. doi: 10.1002/art.24040.
To determine whether methotrexate (MTX) can overcome the atherogenic effects of cyclooxygenase 2 (COX-2) inhibitors and interferon-gamma (IFNgamma), both of which suppress cholesterol efflux protein and promote foam cell transformation in human THP-1 monocyte/macrophages.
Message and protein levels of the reverse cholesterol transport proteins cholesterol 27-hydroxylase and ATP-binding cassette transporter A1 (ABCA1) in THP-1 cells were evaluated by real-time polymerase chain reaction and immunoblot, respectively. Expression was evaluated in cells incubated in the presence or absence of the COX-2 inhibitor NS398 or IFNgamma, with and without MTX. Foam cell transformation of lipid-laden THP-1 macrophages was detected with oil red O staining and light microscopy.
MTX increased 27-hydroxylase message and completely blocked NS398-induced down-regulation of 27-hydroxylase (mean +/- SEM 112.8 +/- 13.1% for NS398 plus MTX versus 71.1 +/- 4.3% for NS398 alone; P < 0.01). MTX also negated COX-2 inhibitor-mediated down-regulation of ABCA1. The ability of MTX to reverse inhibitory effects on 27-hydroxylase and ABCA1 was blocked by the adenosine A2A receptor-specific antagonist ZM241385. MTX also prevented NS398 and IFNgamma from increasing transformation of lipid-laden THP-1 macrophages into foam cells.
This study provides evidence supporting the notion of an atheroprotective effect of MTX. Through adenosine A2A receptor activation, MTX promotes reverse cholesterol transport and limits foam cell formation in THP-1 macrophages. This is the first reported evidence that any commonly used medication can increase expression of antiatherogenic reverse cholesterol transport proteins and can counteract the effects of COX-2 inhibition. Our results suggest that one mechanism by which MTX protects against cardiovascular disease in rheumatoid arthritis patients is through facilitation of cholesterol outflow from cells of the artery wall.
确定甲氨蝶呤（MTX）是否能够克服环氧合酶2（COX - 2）抑制剂和干扰素-γ（IFNγ）的致动脉粥样硬化作用，这两种物质均可抑制胆固醇流出蛋白并促进人THP - 1单核细胞/巨噬细胞向泡沫细胞转化。
分别通过实时聚合酶链反应和免疫印迹法评估THP - 1细胞中逆向胆固醇转运蛋白胆固醇27 - 羟化酶和ATP结合盒转运体A1（ABCA1）的信使核糖核酸和蛋白质水平。在存在或不存在COX - 2抑制剂NS398或IFNγ以及存在或不存在MTX的情况下孵育细胞，评估其表达情况。用油红O染色和光学显微镜检测富含脂质的THP - 1巨噬细胞向泡沫细胞的转化。
MTX增加了27 - 羟化酶信使核糖核酸水平，并完全阻断了NS398诱导的27 - 羟化酶下调（NS398加MTX时为112.8±13.1%，单独使用NS398时为71.1±4.3%；P<0.01）。MTX还消除了COX - 2抑制剂介导的ABCA1下调。MTX逆转对27 - 羟化酶和ABCA1抑制作用的能力被腺苷A2A受体特异性拮抗剂ZM241385阻断。MTX还可防止NS398和IFNγ增加富含脂质的THP - 1巨噬细胞向泡沫细胞的转化。
本研究提供了支持MTX具有抗动脉粥样硬化作用这一观点的证据。通过激活腺苷A2A受体，MTX促进逆向胆固醇转运并限制THP - 1巨噬细胞中泡沫细胞的形成。这是首次报道的关于任何常用药物可增加抗动脉粥样硬化逆向胆固醇转运蛋白表达并可抵消COX - 2抑制作用影响的证据。我们的结果表明，MTX预防类风湿关节炎患者心血管疾病的一种机制是通过促进胆固醇从动脉壁细胞流出。
