Reduced expression of endothelial nitric oxide synthase in pulmonary arteries of smokers

Cigarette smoking has been associated with alterations in the structure and endothelial function of pulmonary arteries. Nitric oxide (NO) and endothelin-1 are endothelium-derived mediators with opposite effects on vascular tone and cell growth. To investigate whether cigarette smoking could induce changes in the synthesis of these mediators in pulmonary arteries, we compared the expression of both endothelial NO synthase (eNOS) and endothelin-1 in the lungs of smokers with that in nonsmokers. Lung tissue samples of 23 smokers and nine nonsmokers were studied. Expression of eNOS and endothelin-1 in pulmonary artery endothelium was evaluated by immunohistochemistry. In protein extracts of lung tissue, the content of eNOS protein was assessed by Western blot analysis and that of endothelin-1 by radioimmunoassay. The immunohistochemical expression of eNOS in arterial endothelium and the eNOS protein content in lung tissue were lower in the smokers than in the nonsmokers. No differences were shown in cell expression and protein content of endothelin-1 between both groups. We conclude that cigarette smoking is associated with reduced expression of eNOS in pulmonary arteries. The diminished synthesis of nitric oxide may contribute to the alterations in the structure and endothelial function of pulmonary vessels in cigarette-smoke-induced respiratory disease.     

Simvastatin attenuates experimental small airway remodelling in rats

Background and objective:   The aim of this study was to assess the beneficial effects of simvastatin on cigarette smoke-induced small airway remodeling in rats.
Methods:   Simvastatin was administered at different doses for 16 weeks to rats with cigarette smoke-induced small airway remodelling. Morphological analyses were performed, and collagen deposition, production of growth factors, inflammatory parameters and RhoA, as well as the Smad signalling pathway in the lungs, were examined.
Results:   Simvastatin attenuated small airway wall thickening and prevented the increase in lung hydroxyproline content and collagen deposition induced in airway walls by cigarette smoking. In addition, simvastatin downregulated transforming growth factor-β₁ and connective tissue growth factor protein and gene expression in the lungs. Furthermore, accumulation of macrophages and neutrophils and increases in tumour necrosis factor-α concentration in BAL fluid were inhibited by simvastatin. Simultaneously, the expression of RhoA and the phosphorylation of Smad2 and Smad3 in lungs exposed to cigarette smoke were inhibited during simvastatin administration. However, the increased expression of Smad2 and Smad3 proteins and the decreased level of Smad7 protein in remodelled lungs were not affected by simvastatin.
Conclusions:   Simvastatin attenuated experimental small airway remodelling, as indicated by decreases in collagen deposition and small airway wall thickening. Simvastatin may inhibit cigarette smoke-induced small airway remodelling by reducing growth factor expression and inflammation. The mechanism of action of simvastatin on small airway remodelling involved RhoA and the Smad signalling pathway. These findings indicate that simvastatin may have potential beneficial effects in the treatment of COPD.     

Tabakrauchen und Lungenerkrankungen

Chronic cigarette smoking is the leading cause of preventable death and primarily affects the airways and lung parenchyma. It is a well-established prime risk factor for the development of chronic obstructive pulmonary disease (COPD) and lung cancer. Chronic cigarette smoking exacerbates pre-existing diseases of the airways and the lung parenchyma such as asthma and various forms of interstitial lung diseases. Additional exposure, e.g. in an occupational setting to asbestos fibres or silica, may act synergistically to increase the risk of lung cancer and pulmonary fibrosis and also of COPD. This paper gives a synopsis of smoking-induced pulmonary diseases with respect to epidemiology and pathology and how cigarette smoking affects the prognosis.     

Genistein, a phytoestrogen, attenuates monocrotaline-induced pulmonary hypertension

BACKGROUND: Pulmonary hypertension is characterized by high pulmonary blood pressure, vascular remodeling, and right ventricular hypertrophy. Although recent studies suggest that an imbalance between endothelial mediators on pulmonary vasculature may contribute to the development of pulmonary hypertension, the pathogenesis is not fully understood and the treatment of pulmonary hypertension is still unresolved. OBJECTIVE: The purpose of this study was to investigate whether genistein, a phytoestrogen derived from soybean, would prevent the development of monocrotaline (MCT)-induced pulmonary hypertension in rats. Hemodynamic parameters of catheterized rats and morphological feature of lungs were evaluated among MCT-treated rats receiving or not receiving genistein. Furthermore, examination of expression in endothelial nitric oxide synthase and endothelin-1 peptide level was performed. METHODS: Daily supplementation with either genistein (0.2 mg/kg) or vehicle was started 2 days prior to a single-dose injection of MCT (60 mg/kg). On day 28, rats underwent catheterization, and right ventricular hypertrophy and morphological features were assessed. Furthermore, endothelial nitric oxide synthase and endothelin-1 were examined by Western blot analysis and radioimmunoassay, respectively, in homogenated lungs. RESULTS: In rats that received daily supplementation of genistein, mean pulmonary arterial pressure was significantly reduced, whereas mean systemic arterial pressure and heart rate were unaltered compared with MCT control rats on day 28 after MCT injection. Right ventricular hypertrophy, medial wall thickness of pulmonary arteries corresponding to the terminal bronchioles, and the degree of neo-muscularization of more distal arteries were less severe in genistein-treated rats. Genistein supplementation improved MCT-induced downregulation of expression of endothelial nitric oxide synthase in the lungs. However, endothelin-1 peptide levels did not differ among all groups of lungs. CONCLUSIONS: We conclude that daily supplementation of genistein potently attenuates MCT-induced pulmonary hypertension, right ventricular hypertrophy, and pulmonary vascular remodeling in rats. The underlying mechanism responsible for this effect may be partly related to the restoration of a decreased expression of endothelial nitric oxide synthase.     

Pulmonary hypertension and chronic obstructive pulmonary disease: a case for treatment

Current pharmacotherapy for chronic obstructive pulmonary disease (COPD) relieves symptoms and reduces exacerbation through improving airflow limitation. Such drugs do not effectively improve exercise tolerance due in part to pulmonary hypertension associated with severe COPD, nor impact on its increased morbidity and mortality. Exercise intolerance is often improved (temporarily) by lung volume reduction surgery and pulmonary rehabilitation. Ambulatory oxygen is the most effective treatment of exercise limitation. Chronic cigarette smoking is the principal cause of COPD. An early change in smokers' lungs is pulmonary artery intimal thickening and vessel narrowing, which, as COPD develops, is correlated with both the severity of emphysema and bronchiolitis. This may be the consequence of combined smoking-induced apoptosis, inflammation, and imperfect repair. End-stage bronchiolitis and emphysema are likely to limit the effectiveness of bronchodilators and corticosteroids. There are effective treatments for idiopathic and scleroderma pulmonary arterial hypertension, which increase exercise tolerance and improve survival. Because idiopathic and COPD pulmonary hypertension share a common vascular intimal thickening, excess endothelin receptor expression, and plasma endothelin-1, an important therapeutic question to address is whether an oral endothelin-1 antagonist can improve exercise tolerance in severe COPD.     

COPD肺动脉高压大鼠肺组织血红素氧合酶1的表达及辛伐他汀治疗对其的影响

目的 研究辛伐他汀对COPD所致肺动脉高压的作用,以及对肺组织血红素氧合酶1(hemeoxygenas-1,HO-1)表达的影响.方法 24只大鼠随机分为3组:对照组、烟雾暴露组和辛伐他汀组.右心导管测定大鼠平均肺动脉压(mean pulmonary arterial pressure,mPAP),以右心室肥厚指数(right ventricular hypertrophy index,RVHI)作为评价右心室肥厚的指标.Real time RT-PCR方法测定肺组织HO-1 mRNA的表达,通过免疫印迹法(Western blot)及免疫组织化学方法检测肺组织HO-1蛋白的表达.结果 烟雾暴露组mPAP[(29.1±1.0) mmHg]、RVHI (0.29±0.004)较对照组[(16.1±1.0) mmHg、(0.21±0.005)]升高(P＜0.01),HO-1 mRNA是对照组的(2.82±1.77)倍;与烟雾暴露组相比,辛伐他汀组mPAP [(21.3±0.7)mm Hg]、RVHI (0.25±0.004)明显降低(P＜0.01),HO-1 mRNA明显升高(P＜0.05),是对照组的(7.56±2.91)倍;Western blot及免疫组织化学结果显示烟雾暴露组大鼠HO-1表达增强,辛伐他汀治疗后表达进一步增强.结论 辛伐他汀降低COPD所致肺动脉高压,其机制和诱导HO-1表达增加有关.     

Simvastatin attenuates smooth muscle neointimal proliferation and pulmonary hypertension in rats

Hypertensive pulmonary vascular disease is characterized by abnormal proliferation of vascular endothelial and smooth muscle cells, leading to occlusion of pulmonary arterioles, pulmonary hypertension, right ventricular failure, and death. Compounds with antiproliferative effects on vascular endothelial and smooth muscle cells, such as 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, may prevent the development of experimental hypertensive pulmonary vascular disease. Pneumonectomized rats injected with monocrotaline at 7 days develop severe hypertensive pulmonary vascular disease with neointimal formation. Rats were randomized to receive either vehicle or treatment with the HMG-CoA reductase inhibitor simvastatin (2 mg/kg per day). By Day 35, rats that received vehicle had higher mean pulmonary arterial pressures (53 +/- 2 mm Hg) and right ventricular hypertrophy (right ventricle/[left ventricle plus septum] [RV/LV+S] = 0.78 +/- 0.09) than rats in Group PMS5-35 that received simvastatin from Day 5 to 35 (mean pulmonary arterial pressure = 27 +/- 3 mm Hg, RV/LV+S = 0.34 +/- 0.08; p < or = 0.001). Pulmonary vascular remodeling with neointimal formation consisting of vascular smooth muscle cells was more severe in vehicle-treated rats (vascular occlusion score, 1.98 +/- 0.02) than in Group PMS5-35 (vascular occlusion score, 0.59 +/- 0.46; p < 0.001). In addition, lung endothelial nitric oxide synthase gene expression was decreased in vehicle-treated animals but was restored toward normal levels in simvastatin-treated animals. Simvastatin attenuates monocrotaline-induced pulmonary vascular remodeling with neointimal formation, pulmonary arterial hypertension, and right ventricular hypertrophy in rats.     

Simvastatin treatment improves liver sinusoidal endothelial dysfunction in CCl4 cirrhotic rats

BACKGROUND/AIMS: Sinusoidal endothelial dysfunction with decreased nitric oxide (NO) production contributes to increased hepatic resistance in cirrhosis. Statins improve endothelial dysfunction in peripheral vasculature. This study was designed to characterize the hemodynamic and molecular effects of statins in cirrhotic rats. METHODS: Systemic and splanchnic hemodynamics were evaluated in CCl(4) ascitic cirrhotic rats treated with placebo or simvastatin (25 mg/kg/day, for 3 days), at baseline and after volume expansion. Vascular responses of liver vasculature were evaluated after isolation and perfusion of the liver. RESULTS: There were no differences in baseline hemodynamics in rats treated with simvastatin or placebo. However, in rats treated with simvastatin the increase in portal pressure induced by volume expansion was significantly attenuated. In isolated and perfused cirrhotic livers simvastatin pre-treatment significantly attenuated the pressure response to methoxamine, and significantly improved paradoxical vasoconstriction induced by acetylcholine. These effects were not observed in the presence of a nitric oxide synthase inhibitor. Simvastatin increased eNOS expression, Akt-dependent eNOS phosphorylation and cGMP liver content. CONCLUSIONS: The administration of simvastatin might constitute a new way to selectively increase NO availability in the cirrhotic liver circulation and, therefore improve the vascular disturbances that contribute to portal hypertension.     

Differential expression of pulmonary nitric oxide synthase isoforms after intestinal ischemia-reperfusion

BACKGROUND/AIMS: Nitric oxide has been implicated in both attenuating and aggravating ischemia-reperfusion injury in most organs. This study aimed to investigate the role of nitric oxide produced by the two principal isoforms of nitric oxide synthase in the lung during post-ischemic reperfusion of the intestine. METHODOLOGY: Rats were randomized into four groups of 6 animals: Group A: laparotomy and superior mesenteric artery dissection without occlusion and maintenance for 2 h (control group at 2 h). Group B: laparatomy and superior mesenteric artery occlusion for 30 min and reperfusion of the intestine for 2 h (ischemia-reperfusion group at 2 h). Group C: control animals at 6 h. Group D: ischemia-reperfusion animals at 6 h. Arterial blood pressure was monitored throughout the procedure. Animals were euthanazed at the end of the experiment, and lungs were harvested for histological assessment of injury and for immunohistochemical examination of nitric oxide synthase isoforms and nitrotyrosine. RESULTS: In all animals subjected to intestinal ischemia a period of systemic hypotension occurred immediately upon reperfusion. Histological evidence of lung injury was limited to those animals subjected to an intestinal reperfusion insult. Compared to control animals, pulmonary endothelial nitric oxide synthase expression was diminished at 2 h (p = 0.002), while expression of inducible nitric oxide synthase (p = 0.002) and nitrotyrosine (p = 0.02) was increased at 6 h. CONCLUSIONS: Following intestinal ischemia-reperfusion, early pulmonary damage is associated with decreased endothelial nitric oxide synthase expression in the lung. Expression of inducible nitric oxide synthase occurs during the later stages of reperfusion; this leads to overproduction of nitric oxide with consequent nitrosylation of protein tyrosine residues and thus aggravated pulmonary injury.     

Effects of monocrotaline on endothelial nitric oxide synthase expression and sulfhydryl levels in rat lungs

The nitric oxide-cyclic guanosine monophosphate signal-transduction mechanism plays a key role in the regulation of vascular tone and structure. Monocrotaline-induced pulmonary hypertension is associated with low bioavailability of nitric oxide. To characterize the mechanism(s) involved in this dysfunction, rats received a single subcutaneous injection of monocrotaline, normal saline (control), or monocrotaline plus daily L-arginine, a precursor of nitric oxide, in drinking water. Pulmonary artery pressure and right ventricular hypertrophy were assessed 2 weeks later. In addition, the authors evaluated the expression of endothelial nitric oxide synthase messenger RNA, endothelial nitric oxide synthase protein, cyclic guanosine monophosphate, and sulfhydryl levels in the lungs. Sulfhydryls are needed for the dynamic modulation of soluble guanylate cyclase by nitric oxide, which results in cyclic guanosine monophosphate formation. L-arginine treatment did not attenuate monocrotaline-induced pulmonary hypertension or right ventricular hypertrophy. Monocrotaline did not alter the expression of endothelial nitric oxide synthase messenger RNA or endothelial nitric oxide synthase protein in the lungs. Protein-bound sulfhydryls (28 +/- 5 vs. 75 +/- 16 pmol/microg protein) and cyclic guanosine monophosphate (0.63 +/- 0.05 vs. 1.06 +/- 0.017 pmol/microg protein) levels in the monocrotaline group were significantly low compared with controls. The low sulfhydryl levels, an indicator of oxidant stress, may account for the impaired availability of bioactive nitric oxide and low cyclic guanosine monophosphate levels. These results suggest that oxidative stress may, in part, contribute to the pathogenesis of pulmonary hypertension in the monocrotaline model.     

辛伐他汀对慢性阻塞性肺疾病合并肺动脉高压患者的影响

目的研究辛伐他汀对慢性阻塞性肺疾病合并肺动脉高压患者疗效的影响,探讨对其肺功能以及对血浆内皮素-1、一氧化氮水平的变化。方法将50例慢性阻塞性肺疾病合并肺动脉高压门诊及住院的患者随机分为治疗组和对照组,治疗组在常规治疗的基础上使用辛伐他汀20mg,每晚一次,对照组只给予常规治疗,疗程均为6个月。治疗前后检测两组患者的肺功能,血清中内皮素-1、一氧化氮的水平。结果治疗组的总有效率为80．0％,高于对照组的52．0％,差异有统计学意义（x2=4．3672,P〈0．05）;治疗组肺功能改善较对照组更明显,血清中内皮素-1、一氧化氮的水平明显降低,与治疗前及对照组比较差异有统计学意义（t=3．2353,7．8333,5．5783,7．0613,3．1224,3．0283,2．0441,2．0281,P〈0．05）。结论辛伐他汀治疗慢性阻塞性肺疾病合并肺动脉高压患者效果可靠,能够降低一氧化氮的水平,改善肺功能及提高疗效,值得临床推广应用。     

Cigarette smoke augments the expression and responses of toll-like receptor 3 in human macrophages

Background and objective: Cigarette smoking is the main risk factor for the development of chronic obstructive pulmonary disease (COPD). Recently, toll‐like receptor 3 (TLR3) was shown to recognize pathogen‐associated molecular patterns, especially viral‐derived double‐stranded RNA, and to be involved in immune responses. However, the effects of cigarette smoke on TLR3 remain unclear. In this study, it was examined whether cigarette smoke affects the expression and responses of TLR3 in human macrophages. Methods: The expression of TLR3 in alveolar macrophages from human lung tissues was analysed by immunohistochemistry, and the correlation of TLR3 expression with smoking history and lung function was evaluated. In addition, the effect of cigarette smoke on the expression and responses of TLR3 in macrophage lineage cells was investigated. Results: TLR3‐positive alveolar macrophage numbers were significantly increased in smokers and COPD patients compared with non‐smoking control subjects, but there was no difference between smokers and COPD patients. TLR3‐positive macrophage numbers were positively correlated with smoking history and inversely correlated with corrected carbon monoxide diffusing capacity, but were not correlated with % predicted forced expiratory volume in 1 s. Furthermore, cigarette smoke extract potentiated the expression of TLR3 in monocyte‐derived macrophages and significantly augmented the release of interleukin‐8, as well as total matrix metalloproteinase‐9 activity, in cells treated with TLR3 ligand. Conclusions: These data suggest that cigarette smoke augments the expression and responses of TLR3 in human macrophages, and this may contribute to neutrophilic airway inflammation and parenchymal destruction in the lungs of smokers and patients with COPD.     

Simvastatin treatment of pulmonary hypertension: an observational case series

BACKGROUND: Statins confer cardiovascular benefits beyond the reduction of serum cholesterol through antiproliferative and antiinflammatory mechanisms and induction of endothelial nitric oxide expression. In pneumonectomized rats injected with monocrotaline, simvastatin reversed established pulmonary hypertension and conferred a 100% survival advantage. STUDY OBJECTIVES: To evaluate the safety and efficacy of simvastatin for treatment of patients with pulmonary arterial hypertension (PAH). DESIGN: Open-label observational study performed at Stanford University Medical Center. Sixteen patients with primary and secondary causes of PAH, World Health Organization (WHO) classes I (n = 2), II (n = 4), III (n = 3), IV (n = 7), are described. Simvastatin was prescribed at 20 to 80 mg/d and continued in the absence of adverse effects. MEASUREMENTS AND RESULTS: Serial measurements of 6-min walk (6MW) performance, hemodynamics, and echocardiographic estimates of right ventricular systolic pressures (RVSPs) were recorded on each patient. Simvastatin treatment was not associated with hepatic dysfunction, muscle necrosis, or other adverse events. Individual patients demonstrated improvements in 6MW performance, improvements in cardiac output, or decreases in RVSP that may be attributable to simvastatin treatment. Overall, the rate of disease progression appeared to be attenuated, and WHO class IV patients demonstrated improved survival. CONCLUSIONS: Simvastatin treatment appears safe in patients with PAH.     

Ischemic and peroxynitrite preconditioning effects in chronic hypoxic rat lung

Chronic hypoxic pulmonary hypertension is characterized by vasoconstriction and vascular remodeling and impaired endothelial nitric oxide (NO) production. Although ischemic preconditioning of the lung leads to protective effect against ischemic reperfusion injury, the mechanisms of this protection are not well documented in the lung. The aim of this study was to investigate the effects of chronic hypoxia on preconditioning induced by ischemia or peroxynitrite in isolated rat lungs. The isolated rat lung, from exposed to hypobaric hypoxia for 21 days, was mounted on a modified Langendorff perfusion apparatus. Lungs were preconditioned by either 5 minutes' ischemia and 5 minutes' reperfusion or 10 microM peroxynitrite prior to 2 hours of normothermic ischemia. Although ischemia-reperfusion or peroxynitrite preconditioning markedly reduced KCl responses on perfusion pressure, phenylephrine-induced responses were not significantly modified. Pretreatment of the hypoxic lungs with peroxynitrite scavenger, uric acid, or poly (ADP-ribose) synthase inhibitors (PARS), 3-aminobenzamide (3-AB) or nicotinamide, did not modify the KCl- and phenylephrine-induced responses in chronic hypoxic lungs. There were also no marked differences either in wet to dry weight ratio or malondialdehyde levels of chronic hypoxic lungs. These results imply that preconditioning does not occur in the chronic hypoxic rat lungs.     

Endothelial dysfunction in the pulmonary vascular bed

The pulmonary endothelium modulates vascular tone by the release of endothelium-derived constricting (EDCF) and relaxing (EDRF) factors, among them endothelin-1, nitric oxide, prostacyclin, and putative endothelium-derived hyperpolarizing factors. Abnormalities in EDCF and EDRF generation have been demonstrated in a number of cardiopulmonary disease states, such as primary and secondary pulmonary hypertension, chronic obstructive lung disease, cardiopulmonary bypass, and congestive heart failure. An imbalance between EDCF and EDRF, termed "pulmonary endothelial dysfunction," may contribute to the alteration in vascular tone characteristic of pulmonary disease. The following review summarizes the present knowledge of the role of EDCF and EDRF in such processes with major focus on pulmonary endothelial dysfunction in hypoxia-induced pulmonary hypertension.     

细胞凋亡与慢性阻塞性肺疾病

慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)定义为气道的慢性炎症、肺实质进行性的破坏.大部分由抽烟引起.涉及到以下几个机制:气道的慢性炎症、蛋白酶/抗蛋白酶失衡、氧化应激.最近的文献提及COPD第4个重要的机制肺内结构细胞的凋亡,血管内皮生长因子在其中起重要作用.凋亡的途径:如caspase-3、神经酰胺等,可以作为预防凋亡和肺气肿发生的靶途径.本篇综述就COPD凋亡机制的相关文献进行讨论.为COPD和肺气肿的凋亡机制提供一些新的文献.     

Simvastatin enhances hepatic nitric oxide production and decreases the hepatic vascular tone in patients with cirrhosis

BACKGROUND & AIMS: In cirrhosis, an insufficient release of nitric oxide contributes to increased hepatic resistance and portal pressure and enhances the postprandial increase in portal pressure. We hypothesized that simvastatin, which enhances Akt-dependent endothelial nitric oxide synthase phosphorylation, may increase hepatic nitric oxide release and decrease hepatic resistance in patients with cirrhosis and portal hypertension. METHODS: In protocol 1, 13 patients had measurements of the hepatic venous pressure gradient, hepatic blood flow, mean arterial pressure, cardiac output, and nitric oxide products before and 30 and 60 minutes after 40 mg of simvastatin. In protocol 2, 17 patients were randomized to receive placebo or simvastatin (40 mg) 12 hours and 1 hour before the study. After baseline measurements of the hepatic venous pressure gradient, hepatic blood flow, and nitric oxide products, a standard liquid meal was given, and measurements were repeated at 15, 30, and 45 minutes. RESULTS: In protocol 1, acute simvastatin did not modify the hepatic venous pressure gradient but increased the hepatic blood flow (21% +/- 13% at 30 minutes; P = 0.01) and decreased hepatic sinusoidal resistance by 14% +/- 11% (P = 0.04). Nitric oxide product levels significantly increased in hepatic venous blood (from 31.4 +/- 12.3 nmol. mL(-1) to 35.8 +/- 10.7 nmol. mL(-1); P = 0.04), but not in peripheral blood. Systemic hemodynamics were not modified. In protocol 2, simvastatin pretreatment significantly attenuated the postprandial increase in hepatic venous pressure gradient (mean peak increase, 10% +/- 9% vs. 21% +/- 6% in placebo; P = 0.01). Hepatic blood flow increased similarly in the 2 groups. Hepatic nitric oxide products increased in the simvastatin group but not in the placebo group. CONCLUSIONS: Simvastatin administration increases the hepatosplanchnic output of nitric oxide products and decreases hepatic resistance in patients with cirrhosis.     

化学趋化因子在慢性阻塞性肺疾病中的作用

慢性阻塞性肺疾病(chronic obstructive pulmonary diseases,COPD)是一组以气流受限,且不完全可逆为特征的肺部疾病,认为与肺部对有害气体或有毒颗粒的异常炎症反应有关.目前仍缺乏有效的治疗手段.其诱发慢性炎症的具体细胞分子学机制仍不清楚.然而,越来越多的证据表明香烟诱导的炎症细胞的募集取决于趋化因子及其配体的调节.这里主要探讨CXC-和CC-家族与各种炎性细胞的相互调节,通过阻断趋化因子而减少COPD患者的炎性细胞浸润及实质破坏可能为一种有效的抗炎策略.     

Senescence marker protein-30 protects mice lungs from oxidative stress, aging, and smoking

RATIONALE: Senescence marker protein-30 (SMP30) is a multifunctional protein providing protection to cellular functions from age-associated deterioration. We previously reported that SMP30 knockout (SMP30Y/-) mice are capable of being novel models for senile lung with age-related airspace enlargement and enhanced susceptibility to harmful stimuli. OBJECTIVES: Aging and smoking are considered as major contributing factors for the development of pulmonary emphysema. We evaluated whether SMP30Y/- mice are susceptible to oxidative stress associated with aging and smoking. METHODS: Age-related changes of protein carbonyls in lung tissues from the wild-type (SMP30Y/+) and SMP30Y/- mice were evaluated. Both strains were exposed to cigarette smoke for 8 wk. Histopathologic and morphologic evaluations of the lungs, protein carbonyls and malondialdehyde in the lung tissues, total glutathione content in the bronchoalveolar lavage fluid, and degree of apoptosis of lung cells were determined. MEASUREMENTS AND MAIN RESULTS: In the lungs of SMP30Y/- mice, protein carbonyls tended to increase with aging and were significantly higher than the age-matched SMP30Y/+ mice. Cigarette smoke exposure generated marked airspace enlargement (23.3% increase of the mean linear intercepts) with significant parenchymal destruction in the SMP30Y/- mice but not in the SMP30Y/+ mice (5.4%). The protein carbonyls, malondialdehyde, total glutathione, and apoptosis of lung cells were significantly increased after 8-wk exposure to cigarette smoke in the SMP30Y/- mice. Conclusions: Our results suggest that SMP30 protects mice lungs from oxidative stress associated with aging and smoking. The SMP30Y/- mice could be useful animal models for investigating age-related lung diseases, including cigarette smoke-induced pulmonary emphysema.