ESR spin trapping studies on the free radicals in gasphase of cigarette smoking.

Free radicals in the gasphase of cigarette smoke were determined by spin trapping agent PBN (N-tert-butyl-2-phenyl nitrone) and DMPO (5,5-dimethyl-1-pyrroline-oxide) on electron spin resonance spectrometer. They were identified according to the spectrum parameters calculated from the spectra. The free radicals mainly consist of alkoxyl and alkyl free radicals, of which alkoxyl free radicals make up 60-70% of the total spectral components. These free radicals are very active and reactive. They can damage cells and lead to some diseases. This work points out the importance of scavenging the free radicals of cigarette smoke to prevent diseases caused by them.

     

香烟烟雾引起的氧化应激在肺泡Ⅱ型上皮细胞损伤中的作用

香烟烟雾中含有自由基等大量的强氧化剂,因而可以导致氧化应激。氧化应激可对肺泡Ⅱ型上皮细胞(AECⅡ)造成损伤,但是其对AECⅡ造成损伤的机制至今还未完全清楚,近期这个领域研究的热点集中在三个方面:氧化应激诱导的AECⅡ凋亡、氧化应激与炎性反应的相互作用对AECⅡ的损伤以及氧化应激对AECⅡ结构和功能的直接损伤。AECⅡ损伤与肺部损伤有密切关系,对其损伤机制的研究,有助于呼吸道疾病的诊断和治疗。     

降低卷烟烟气中多环芳烃和自由基的中药添加剂

研究了降低卷烟烟气中多环芳烃和自由基的中药添加剂。通过正交实验优化条件提取有效成分为添加剂 ,采用邻苯三酚自氧化紫外方法和荧光法筛选中药 ,得几种中草药的复方 ,喷洒于烟丝卷制成烟支后 ,利用电子自旋共振波谱仪 ( ESR)及气相色谱 /质谱法 ( GC/MS) ,对卷烟焦油中多环芳烃和焦油及烟气中自由基含量进行测定分析。实验结果表明 ,该添加剂对卷烟焦油中多环芳烃和焦油及烟气中的自由基含量具有良好的降低作用     

抑制SCD1对被动吸烟小鼠肺部炎症的影响

目的 研究硬脂酰辅酶A去饱和酶1（stearoyl-CoA desaturase 1,SCD1）对被动吸烟小鼠肺部炎症水平的影响。方法 将C57BL/6小鼠随机分为对照（CON）组、SCD1抑制剂（CAY）组、吸烟（Smoke）组及吸烟加抑制剂（Smoke+CAY）组,每组11~14只,记录各组小鼠体重及肝脏系数。RT-qPCR及Western blot检测CON组与Smoke组内SCD1表达水平。肺组织HE病理染色、肺泡灌洗液（bronchoalveolar lavage fluid,BALF）蛋白浓度测定及细胞计数比较肺部炎症损伤水平。ELISA检测BALF中TNF-α、IL-6、IL-1β水平。电化学发光法检测血浆中IL-4、IL-10、IL-13水平。结果 被动吸烟小鼠肺内SCD1水平升高。给予SCD1抑制剂后,小鼠体重减轻、肝脏系数降低。Smoke+CAY组小鼠较其他组肺部炎症改变明显,BALF中蛋白浓度、细胞计数、TNF-α、IL-6、IL-1β水平均明显升高。各组血浆中IL-4、IL-10、IL-13水平变化不明显。结论 吸烟后小鼠肺内SCD1水平升高,且抑制SCD1会加重被动吸烟小鼠肺部炎症损伤。     

芳香烃羟化酶活性与苯并[a]芘中间代谢产物生成关系的研究

100mg香烟烟油,多氯联苯诱导大鼠肝S_9组分中芳香烃羟化酶代谢B[a]P为3-OH-B[a]P的活性分别升高约40,20倍,而代谢B[a] P生成6-OXY-B [a]P自由基产物却仅由多氯联苯诱导的S_9组分作用中才被观察到。     

β-carotene protects rats against bronchitis induced by cigarette smoking

Objective To investigate the protective effects of B-carotene in rats against the development of chronic bronchitis induced by cigarette smoking.Methods Forty-two Male Wistar rats were randomly divided into three study groups: ①control (n =15), animals underwent no treatment; ②cigarette smoking (n = 15), animals developed chronic bronchitis through long-term cigarette smoking twice a day for 75 d; ③β-carotene plus cigarette smoking animals (n =12) were given 1 ml or 15 mg/kg β-carotene orally every day just before cigarette smoking. The levels of IL-6, IL-8, NO, superoxide dismutase (SOD) and lipoperoxide(LPO) in serum, bronchoalveolar lavage fluid (BALF) and lung tissue were measured and the pathological changes to lung tissue were analyzed using light microscopy.Fiesults Long-term cigarette smoking caused an obvious increase in the amount of IL-6, IL-8 and LPO and a sharp decrease in the levels of NO and SOD in smoking animals compared to controls. β-carotene intake reversed all the changes induced by smoking and alleviated the pathological changes caused by chronic bronchitis.Conclusions Quantitative oral intake of B-carotene had protective effects against chronic bronchitis induced by long-term cigarette smoking, which was associated with the increased production of NO,the clearance of some oxidative free radicals (OFR) and the alleviation of chronic inflammation.     

豚鼠定量吸香烟模型及其肺气道反应

目的 :建立豚鼠定量吸香烟模型 ,同时观察定量吸烟引起的肺气道急性反应。方法 :制作双通道、单向、最小无效腔的动物定量吸烟装置 ;观察豚鼠自主呼吸时吸入 75 %浓度的香烟烟雾 10次呼吸后的肺气道阻力 (RL)和肺动态顺应性 (Cdyn)的变化 ;观察豚鼠连续吸入 6 0 ml香烟烟雾后 ,肺气道组织小血管的通透性的变化。结果 :豚鼠吸烟后 RL 迅速提高 ,峰值出现在第 9～ 11次呼吸波段 ,是吸烟前基础值的 191± 6 3% (P<0 .0 1) ;吸烟后 Cdyn迅速降低 ,谷值也在第 9～ 11次呼吸波段 ,是基础值的 6 1± 19% (P<0 .0 1) ;吸烟后豚鼠胸腔内气管段、主支气管段、近端肺内气道段和远端肺内气道段组织中的伊文思蓝渗出量与对照组相比 ,均有明显增加 (P<0 .0 1)。结论 :建立了豚鼠自主呼吸定量吸香烟模型 ,可用于检测吸烟后肺气道的急性反应 ;豚鼠急性定量吸烟可引起肺气道阻力明显上升 ,肺动态顺应性明显下降 ,还可引起肺气道组织小血管通透性明显增高的反应。     

Role of extracellular signal-regulated kinase 1/2 in cigarette smoke-induced mucus hypersecretion in a rat model

Background  Airway mucus hypersecretion is an important pathophysiological feature of chronic obstructive pulmonary disease, which is closely associated with cigarette smoking. However, the signal transduction pathway from the cell surface to the nucleus through which cigarette smoke causes upregulation of mucin gene expression is not well known. This study was designed to investigate the role of extracellular signal-regulated Kinase 1/2 (ERK 1/2) in airway mucus hypersecretion induced by cigarette smoke in rats.

Methods  A rat model of airway mucus hypersecretion was induced by exposure to cigarette smoke for 4 weeks．Rats exposed to inhalation of cigarette smoke or normal saline were given an intraperitoneal injection of U0126, a specific MEK1 kinase inhibitor, at doses of 0.25 mg/kg, 0.5 mg/kg and 1 mg/kg for 14 days. Expression of MUC5AC mRNA and protein, ERK 1/2 and phosphorylated-ERK 1/2 (p-ERK 1/2) were detected by RT-PCR, immunohistochemistry and Western blotting.

Results  Cigarette smoke significantly increased airway goblet cells metaplasia, induced the overexpression of MUC5AC mRNA and protein in bronchial epithelia, and increased the ratio of p-ERK 1/2 and ERK 1/2. U0126 significantly attentuated the expression of MUC5AC mRNA and protein induced by cigarette smoke (P <0.05). Moreover, there was a significant positive correlation between the ratio of p-ERK1/2 to ERK1/2 and the expression of MUC5AC mRNA and protein (P <0.05).

Conclusions  Inhibition of ERK 1/2 by U0126 decreased the ratio of p-ERK 1/2 to ERK 1/2 and expression of MUC5AC mRNA and protein. ERK 1/2 may play an essential role in cigarette smoke-induced mucus hypersecretion in vivo.

     

SOD对鼠冷冻伤脑水肿的保护作用

用电子自旋共振技术(ESR)及自旋捕捉剂(PBN)直接检测冷冻伤及伤后应用SOD、甘露醇治疗的脑组织自由基动态改变;同时检测丙二醛(MDA)、SOD活性及脑组织水含量。结果治疗组和对照组相比,自由基、MDA、水含量明显降低(P<0.01)。SOD含量回升(P<0.01);SOD比甘露醇疗效更显著(P<0.05)。提示SOD、甘露醇都有抗自由基作用;超氧阴离子自由基O_2~(?)在病理性自由基反应中具有重要作用。     

冬凌草甲素对活性氧自由基的清除作用(英文)

目的：研究冬凌草甲素对不同模型系统产生的活性氧自由基的清除作用。方法：自由基检测用电子自旋共振自由基旋捕集技术和化学发光法。结果：二种方法检测均发现Ｏｒｉｄ明显清除黄嘌呤／黄嘌呤氧化酶系统产生的超氧自由基（Ｏ－２）以及Ｆｅｎｔｏｎ反应中的羟自由基（·ＯＨ）．Ｏｒｉｄ１７０ｍｏｌ／Ｌ对Ｏ－２和·ＯＨ的清除率分别为４９４％和７５２％。Ｏｒｉｄ对多形核白细胞（ＰＭＮ）呼吸爆发时产生活性氧自由基同样显示明显清除作用。在本实验条件下,Ｏｒｉｄ并不影响ＰＭＮ呼吸爆发时的氧消耗。结论：Ｏｒｉｄ可能是一个抗氧化剂。     

Blood carboxyhaemoglobin, plasma thiocyanate, and cigarette consumption: implications for epidemiological studies in smokers

Carboxyhaemoglobin and plasma thiocyanate concentrations were found to be significantly correlated with self-reported daily cigarette consumption in 360 smokers (r = 0.416 and 0.412 respectively; p less than 0.001). The extent to which inhalation patterns affected the intake of cigarette smoke constituents was determined from the partial correlation between carboxyhaemoglobin and plasma thiocyanate concentrations after the number of cigarettes smoke per day had been allowed for (r = 0.48). Thus 23% of the variation in carboxyhaemoglobin and thiocyanate concentrations was accounted for by the was a cigarette was smoked and a further 21% by the number smoked a day. Furthermore, the relation between carboxyhaemoglobin or plasma thiocyanate and daily cigarette consumption was not linear but reached an asymptote at consumption rates above 25 cigarettes a day. These results suggest that by itself daily cigarette consumption will not identify those smokers most at risk and will also underestimate and dose-response relationship between smoking and selected diseases.     

脂多糖结合熏烟法和单纯熏烟法建立慢性阻塞性肺病大鼠模型的比较

目的比较熏香烟加气道内注入脂多糖(LPS)法和单纯熏香烟法建立慢性阻塞性肺病(COPD)大鼠模型的效果。方法8周龄Wistar大鼠24只,随机分为3组,每组8只。其中1组作健康对照,另2组分别进行熏香烟加气道内注入LPS和单纯熏香烟处理建立COPD模型。观察动物一般情况和肺组织病理学,测定肺组织平均内衬间隔(MLI)和平均肺泡数(MAN);检测外周血常规和支气管肺泡灌洗液(BALF)常规。结果两个模型组大鼠消瘦,伴有间歇咳嗽和气促,外周血和BALF中的白细胞总数及中性粒细胞百分比均较对照组明显增高(P<0.01);肺组织H-E染色显示两个模型组大鼠均具有慢性支气管炎和肺气肿的典型病变,MLI较对照组明显增高,而MAN较对照组明显下降(P<0.01),但两个模型组组间差异无统计学意义;熏香烟加气道内注入LPS组比单纯熏香烟组气道及肺组织的炎症浸润更明显,单纯熏香烟组主要表现为肺泡过度扩张。结论熏香烟加气道内注入LPS和单纯熏香烟两种方法均可成功制备大鼠COPD模型,其病理生理改变与人类COPD类似,前者比后者更符合COPD自然发病过程。     

低剂量γ射线与香烟对人外周血淋巴细胞微核率的影响

目的探讨低剂量γ－射线和香烟烟雾的诱变作用。方法取人外周血随机分成香烟烟雾组，γ射线组和香烟烟雾与γ射线联合组，进行微量全血培养，然后分别用不同剂量（０、０．２５、０．５、１．０Ｇｙ）的６０Ｃｏγ射线和不同浓度（０、０．２、０．４、０．６、０．８、１．０支）香烟烟雾进行处理，并检测和统计淋巴细胞微核。结果香烟烟雾（０．８、支）与低剂量γ射线（０．５、１．０Ｇｙ）均能提高淋巴细胞微核的形成（Ｐ＜０．０１），并具有剂量依赖效应；低剂量γ射线联合香烟烟雾处理淋巴细胞，诱发微核率显著高于对照组、单独照射组和香烟烟雾组（Ｐ＜０．０１）。结论低剂量γ射线联合香烟烟雾可加强遗传物质的损伤。     

Cigarette smoke induced oxidative insult in local population of Pokhara.

Objectives: To assess the effect of cigarette smoking on lipid peroxidation induced oxidative stress, antioxidants, uric acid and blood sugar in normal subjects. Methods: The study included 61 normal subjects with regular smoking habit and 57 never-smokers normal subjects matched in respect to socio-economic status, age and BMI. Information regarding smoking habit and other personal details were collected by oral questionnaire. Total antioxidant activity (TAA), reduced glutathione (GSH), alpha-tocopherol (alpha-T), ascorbic acid (AA), uric acid (UA), plasma and urinary thiobarbituric acid reactive substances (TBARS), fasting blood sugar (FBS) and urinary creatinine (Cr) were estimated by standard procedures in both the groups. Ferric Reducing Antioxidant Power (FRAP) procedure is used to estimate TAA which measures total dietary antioxidants. Statistical analysis was done with SPSS version 10. Results: The mean pack years smoked by smokers was 14.4 +/- 15.8. The plasma TBARS level in smokers and never-smokers was 2.6 +/- 0.8 and 2.5 +/- 0.6 micromol/L respectively. The respective figure for urinary TBARS level was 4.6 +/- 2.7 and 3.7 +/- 1.4 micromol/gmCr. Smokers did not show any significant difference from never-smokers with respect to GSH, alpha-T, AA, plasma TBARS and FBS. However, the smokers had significantly lower levels of TAA (p<0.05) and raised level of urinary TBARS (p<0.05) and uric acid (p<0.01) as compared to never-smokers. Conclusion: Our study suggests that smoking induces mild lipid peroxidation but the body is able to compensate for it by removing its adducts. Importantly it also indicates enhanced oxidation of purines which are essential components of both DNA and RNA. Dietary antioxidants are consumed to scavenge free radicals (FR) and other reactive species (RS) in smoke. Female smokers are more prone to oxidative insult than male smokers. In summary RS present in smoke induce mild lipid peroxidation but are not the major contributors of redox imbalance in smoke induced toxicity in the selected subjects. Key words: Tobacco, Smoking, Free radicals, Oxidative stress, Antioxidants.     

Effect of cigarette smoke extraction on the expression of found in inflammatory zone 1 in rat lung epithelial L2 cells

Background Found in inflammatory zone 1 （FIZZ1） protein increased in pulmonary epithelial cells and in limited amounts of other lung cells.FIZZ1 increased in murine model of smoke induced chronic obstructive pulmonary disease.However,the direct role of FIZZ1 produced by pulmonary epithelium stimulated with cigarette smoke extraction has not been determined.We examined the expression and function of FIZZ1 in rat lung epithelial L2 cells.Methods The rat lung epithelial L2 cells （CCL 149） were exposed to cigarette smoke extraction,expression of FIZZ1 mRNA was investigated by RT-PCR.Levels of FIZZ1 protein were detected by Western blotting and laser confocal microscope.CCL 149 cells were treated with different concentrations and for different time of recombinant protein FIZZ1.After treatment,the expression levels of interleukin 8 （IL-8） were detected by enzyme-linked immunosorbent assay （ELISA）.Results When CCL 149 cells were exposed to cigarette smoke extraction,FIZZ1 mRNA and protein levels expressed significantly higher than control group.Recombinant protein FIZZ1 promoted the expression of IL-8 in a dose and time dependent manner in a certain range.Conclusions Cigarette smoke extraction activates FIZZ1 at mRNA and protein levels in CCL 149 cells.Recombinant protein FIZZ1 induces the expression of IL-8 and may thus participate in the process of chronic obstructive pulmonary disease airway inflammation and airflow obstruction.Generally,immune cells such as macrophages,neutrophils and lymphocytes are unavoidably involved in airway inflammatory and immune responses to cigarette smoke,but it is still unclear whether their involvement in the pathogenesis of chronic obstructive pulmonary disease is based on the specific expression in lung epithelial cells of FIZZ1.     

香烟烟雾对人支气管上皮细胞氧化应激作用研究

目的观察香烟形成的可吸入并沉积在呼吸道的香烟烟雾是否对人支气管上皮细胞造成的氧化应激。方法用FA-1型多级撞击式空气采样器对形成的烟雾进行采样,收集到6种大小不同的香烟烟雾颗粒,将采得的不同大小的香烟烟雾颗粒分别对人支气管上皮细胞（16HBE）进行刺激。6h后用荧光探针检测16HBE细胞中的活性氧。结果与未加香烟烟雾颗粒刺激对照组比较,香烟烟雾颗粒明显造成人支气管上皮细胞中活性氧增加。不同大小香烟烟雾颗粒中,第四级（2．1-3．3μm）的香烟烟雾颗粒造成的氧化应激最明显。第六级（0．65～1．1μm）大小的颗粒能直接对人支气管上皮细胞造成损伤。结论可吸入并沉积在呼吸道中的香烟烟雾能造成呼吸道上皮细胞的氧化损伤。也能对呼吸道上皮细胞造成直接损伤。     

香烟烟雾暴露对中国树鼩CXCR4、MHC-1、TNF-α、MCP mRNA表达的影响

目的观察香烟烟雾暴露对中国树鼩(Tupaia belangeri chinensis)血液、肺脏、心肌及支气管趋化因子受体4(CXCR4)、主要组织相容性复合体-1(MHC-1)、肿瘤坏死因子-α(TNF-α)、单核细胞趋化蛋白(MCP)mRNA表达的影响,探讨香烟烟雾暴露与炎性相关细胞因子表达的关系及中国树鼩作为实验动物的应用价值。方法以灵长目中国树鼩为实验动物,动式染毒装置进行烟雾暴露12周,采集股静脉血0.5 mL,经股动脉放血合并颈椎脱臼法处死中国树鼩后,分别取肺、心脏及支气管组织100 mg。以GAPDH为内参,实时逆转录聚合酶链反应(RT-PCR)法测定吸入组及非吸入组中国树鼩的外周血、肺脏、心肌及支气管组织CXCR4、MHC-1、TNF-α、MCPmRNA的表达。结果烟雾暴露12周后吸入组中国树鼩外周血和支气管CXCR4表达量明显低于对照组(P<0.05),吸入组中国树鼩外周血中TNF-α表达量明显高于对照组(P<0.05);MHC-1、MCPmRNA表达量未见明显变化。结论香烟烟雾暴露可引起CXCR4和TNF-α的表达变化。中国树鼩对香烟烟雾暴露较敏感,是具有开发应用价值的灵长目实验动物。     

香烟烟雾暴露的大鼠晶状体白内障样改变中高度糖化终末产物及其相关荧光的研究

目的：通过检测在体暴露于香烟烟雾大鼠的晶状体中的高度糖化终末产物及其相关荧光，探讨香烟烟雾凝聚物在吸烟致大鼠晶状体白内障样改变中的可能作用机制。方法：雄性Wistar大鼠随机分2组，实验组每天暴露于香烟烟雾1h，连续90d，对照组大鼠只暴露于普通室内空气，其他条件相同。每只大鼠两只眼球在处死后摘除，一只做组织病理学检查，另一只用于研究体内糖化情况。荧光质谱仪检测激发吸收光370／440nm处高度糖化终末产物相关荧光，并通过HPLC检测N-羧甲基赖氨酸及pentosidine。结果：实验组晶状体上皮细胞发生显著组织形态学改变。如增生、肥大，上皮多层化，并有晶体上皮细胞移行于晶状体后囊，对照组未见上述改变。吸烟组晶体水溶性和非水溶性组分中高度糖化终末产物荧光和N-羧甲基赖氨酸及pentosidine显著升高。结论：香烟烟雾吸入致大鼠晶状体白内障样改变，伴随高度糖化终末产物形成，糖化是吸烟致白内障形成的一个可能机制。     

别嘌呤醇对大鼠再灌流脑自由基生成的影响

本文采用电子自旋共振(ESR)技术,观测了缺血和再灌流大鼠脑组织的自由基含量以及别嘌呤醇对再灌流脑自由基生成的影响。结果是:缺血组脑自由基含量显著高于对照组(P<0.01);再灌流组又显著高于缺血组(P<0.01);别嘌呤醇组则显著低于再灌流组(P<0.01)。研究表明:脑缺血-再灌流后,自由基大量增加;别嘌呤醇对再灌流脑自由基的生成有一定抑制作用.