Department of Medical Sciences, School of Medicine, University of Piemonte Orientale A Avogadro, Novara, Italy.
Br J Pharmacol. 2009 Nov;158(5):1276-84. doi: 10.1111/j.1476-5381.2009.00442.x. Epub 2009 Oct 8.
Tobacco smoke represents a relevant risk factor for coronary heart disease (CHD). Although peroxisome proliferator-activated receptor (PPAR)gamma activation reduces inflammation and atherosclerosis, expression of PPARgamma in cells and its modulation by smoking are poorly investigated. We previously reported that monocyte/macrophages from healthy smokers exhibited an enhanced constitutive expression of PPARgamma. Here, we evaluated PPARgamma expression and basal cytokine release in monocytes and monocyte-derived macrophages (MDMs) from 85 CHD patients, classified by their smoking habit (smokers, non-smokers and ex-smokers), and assessed the role of PPARgamma ligands in this context.
PPARgamma protein was detected by Western blot and semi-quantified by PPARgamma/beta-actin ratio; cytokine release was measured by elisa and nuclear factor-kappaB (NF-kappaB) translocation by electrophoretic mobility shift assays.
As compared to the other groups, MDMs from smoker CHD patients exhibited a reduced PPARgamma/beta-actin ratio and an increased spontaneous release of tumour necrosis factor-alpha (TNF-alpha) and interleukin-6, but with no major variations in monocytes. In cells from selected CHD patients, rosiglitazone inhibited TNF-alpha release and NF-kappaB translocation induced by phorbol-12-myristate 13-acetate. The selective PPARgamma antagonist GW9662 reversed these effects, with some variations related to smoking habit.
In CHD patients, exposure to tobacco smoke profoundly affected PPARgamma expression, and this was related to levels of secretion of pro-inflammatory cytokines. MDMs from CHD smokers showed the lowest PPARgamma expression and released more inflammatory cytokines. Moreover, rosiglitazone's ability to inhibit cytokine release and its reversal by GW9662 clearly indicated PPARgamma involvement in these changes in CHD patients.
烟草烟雾是冠心病（CHD）的一个重要危险因素。虽然过氧化物酶体增殖物激活受体（PPAR）γ的激活可以减少炎症和动脉粥样硬化，但细胞中 PPARγ的表达及其受吸烟的调节作用仍未得到充分研究。我们之前报道过，健康吸烟者的单核细胞/巨噬细胞表现出增强的 PPARγ组成型表达。在这里，我们评估了 85 名 CHD 患者的单核细胞和单核细胞衍生的巨噬细胞（MDM）中 PPARγ的表达和基础细胞因子释放情况，这些患者根据其吸烟习惯（吸烟者、非吸烟者和戒烟者）进行了分类，并评估了 PPARγ配体在这种情况下的作用。
通过 Western blot 检测 PPARγ蛋白，并通过 PPARγ/β-肌动蛋白比值进行半定量；通过 ELISA 测量细胞因子释放，通过电泳迁移率变动分析测量核因子-kappaB（NF-κB）易位。
与其他组相比，吸烟者 CHD 患者的 MDM 表现出降低的 PPARγ/β-肌动蛋白比值和自发释放肿瘤坏死因子-α（TNF-α）和白细胞介素-6 的增加，但单核细胞没有发生重大变化。在选择的 CHD 患者的细胞中，罗格列酮抑制了佛波醇 12-肉豆蔻酸 13-乙酸酯诱导的 TNF-α释放和 NF-κB 易位。选择性 PPARγ拮抗剂 GW9662 逆转了这些作用，与吸烟习惯有关。
在 CHD 患者中，暴露于烟草烟雾显著影响了 PPARγ的表达，这与促炎细胞因子的分泌水平有关。CHD 吸烟者的 MDM 表现出最低的 PPARγ表达并释放更多的炎症细胞因子。此外，罗格列酮抑制细胞因子释放的能力及其被 GW9662 逆转，这清楚地表明 PPARγ参与了 CHD 患者的这些变化。
