屋尘螨致敏/激发小鼠气道变态反应性炎症模型的构建

目的使用屋尘螨(HDM)提取液致敏和激发C57BL/6小鼠构建气道变态反应性炎症模型的方法。方法模型组和对照组,各8只。模型组以HDM致敏和激发小鼠,分别于第0、7、14、21天腹腔注射HDM,10 d后,连续雾化吸入HDM 3 d。对照组以PBS代替HDM。进行支气管肺泡灌洗液(BALF)细胞总数计数和分类计数,肺组织病理检查,ELISA测定BALF上清中IL-4、IL-5和IFNγ-水平。结果模型组可见明显炎性细胞浸润,以嗜酸性粒细胞为主。而对照组未见明显炎性细胞浸润。BALF中细胞总数计数和嗜酸性粒细胞比例较对照组明显升高(P<0.01);BALF上清中IL-4、IL-5水平较对照组明显升高(P<0.001),IFNγ-水平较对照组降低(P<0.01)。结论使用HDM致敏和激发C57BL/6小鼠成功地建立了小鼠气道变应性炎症模型。     

一种经济稳定的小鼠腭裂模型的建立

目的利用四氯二苯并二恶英(tetrachlorodibenzo-p-dioxin,TCDD)建立稳定高效的昆明小鼠腭裂模型。方法采用不同剂量的TCDD作用于不同妊娠天数的昆明小鼠,观察胎鼠腭裂的发生情况以及药物的毒性影响,确定诱导形成腭裂的最佳条件。结果孕12.5天的昆明小鼠给予一次性灌胃40μg/kg TCDD,可诱导胎鼠腭裂发生率为98.04%。显微镜下观察:13.5天时,实验组及对照组侧腭突位于舌两侧;14.5天时,对照组侧腭突增大并上抬,呈对向生长,头部开始融合;实验组侧腭突增大,未出现上抬以及融合。15.5和16.5天时,对照组侧腭突完全融合,实验组侧腭突上抬至舌上方,但体积较小,未出现融合,形成腭裂。16.5天时,胎鼠的肝、肺无明显组织学结构异常。结论昆明小鼠于孕12.5天一次性灌胃40μg/kg TCDD可建立稳定高效的小鼠腭裂动物模型;TCDD主要通过延迟侧腭突上抬诱导昆明小鼠腭裂发生。     

DNCB诱导昆明小鼠特应性皮炎模型的建立

目的探索外用1-氯-2,4-二硝基苯(DNCB)经皮肤致敏并激发昆明小鼠特应性皮炎(Atopic Dermititis)模型的方法。方法 10只昆明小鼠随机分成两组(n=5)。用1%DNCB致敏及4%SDS+0.5%DNCB激发模型组小鼠,以丙酮、橄榄油混合溶液致敏并激发对照组小鼠,药物作用部位均为双侧耳朵及背部皮肤。观察小鼠耳朵厚度、组织病理学、免疫学指标,评价皮炎损伤程度。结果外用DNCB可以引起昆明小鼠明显的特应性皮炎样皮损。模型组小鼠出现皮肤干燥、红斑、水肿、糜烂,利用HE染色进行组织病理分析,显示表皮和真皮增厚、过度角质化和炎症细胞浸润。结论先后外用1%DNCB和4%SDS+0.5%DNCB重复刺激昆明小鼠可引起皮肤生理和病理的改变,与AD患者临床表现基本一致,成功建立特应性皮炎模型。可以作为研究AD病因及治疗AD的有效动物模型。     

M16添加硫氧还蛋白过氧化物酶Ⅱ无法克服昆明小鼠早胚体外发育2-细胞阻滞

目的观察硫氧还蛋白过氧化物酶Ⅱ(Peroxiredoxin Ⅱ,PrxII)是否可以克服昆明(Kunming)小鼠早胚体外发育2-细胞阻滞。方法取昆明小鼠1-细胞胚置于含PrxII蛋白的M16培养液中培养,观察PrxII对昆明小鼠早胚发育潜能和2-细胞胚内活性氧自由基(reactive oxygen species,ROS)水平的影响;同时比较昆明和B6C3F1小鼠1-细胞胚在M16中各自的发育情况;激光扫描共聚焦显微镜分别检测比较昆明与B6C3F1小鼠体外培养2-细胞胚内ROS水平以及昆明小鼠体外培养与体内发育2-细胞胚内ROS水平。结果M16培养液中添加PrxII蛋白(1nmol/L和100nMol/L)可以明显降低昆明小鼠体外培养2-细胞胚内ROS水平(P<0.05),但不能克服昆明小鼠体外发育2-细胞阻滞;昆明小鼠1-细胞胚在M16中培养存在2-细胞阻滞现象,而B6C3F1小鼠无2-细胞阻滞现象;昆明小鼠体外培养2-细胞胚内ROS水平显著低于体内发育2-细胞胚(P<0.05),亦略低于B6C3F1小鼠体外培养2-细胞胚内ROS水平(P>0.05)。结论M16培养液中添加PrxII可以明显降低2-细胞胚...     

青蒿琥酯治疗肺烟曲霉感染自噬机制

目的探究青蒿琥酯在鼠肺感染烟曲霉后,对鼠肺自噬相关蛋白的表达影响。方法用一定量的烟曲霉的活化孢子感染鼠肺,建立肺烟曲霉病模型。同时用青蒿琥酯注射一组鼠肺,两性霉素B注射一组鼠肺,剩余的作为感染组。24h后,取各组鼠肺进行病理切片染色,观察各组病理情况;取各组鼠肺的组织并匀浆,收集各组的孢子,用真菌活性检测试剂盒检测孢子活性并将肺巨噬细胞进行分离、裂解,离心取上清,用Western-blot法检测上清液中的Dectin-1、ROS、LC3Ⅱ的表达水平。结果青蒿琥酯注射组的鼠肺病理切片中的孢子比感染组数量少且聚集在一起,未长出菌丝,而体外分离的真菌孢子,青蒿琥酯组的活性明显受到抑制。经Western-blot显示青蒿琥酯具有增强肺巨噬细胞Dectin-1、ROS、LC3Ⅱ的表达。结论青蒿琥酯可通过抑制烟曲霉的活性和增强鼠肺巨噬细胞的自噬水平,对抗鼠肺烟曲霉感染。     

昆明小鼠和DBA/2小鼠尾静脉注射L1210细胞的比较研究

目的:通过尾静脉注射L1210细胞建立昆明小鼠及DBA/2小鼠的白血病模型,观察肿瘤细胞的迁移情况以及小鼠存活时间,为后续L1210细胞迁移的细胞内信号通路研究及抗肿瘤药物筛选奠定基础。方法:常规培养小鼠白血病细胞L1210系,将昆明小鼠及DBA/2小鼠随机分为对照组(A、C)和实验组(B、D),实验组尾静脉注射5×10^6L1210细胞,对照组注射等体积的PBS。昆明小鼠组饲养56d,DBA/2小鼠组饲养14d。定期测量小鼠体重并观察小鼠形态,取濒死小鼠以及最后解剖的小鼠的心、肝、脾、肺等脏器称重并测量,统计结果。结果:A、B、C、D组小鼠的平均存活天数分别为56、56、13.83±0.37、10.33±3.40d。昆明小鼠实验组脾脏明显肿大,肺脏有少量白细胞浸润,心脏和肝脏无明显变化,无死亡现象;DBA/2小鼠注射L1210细胞后第7d开始出现死亡,随着饲养时间的延长,死亡率不断上升。结论:昆明小鼠或DBA/2小鼠尾静脉注射L1210细胞均可引起肿瘤细胞的体内浸润。昆明小鼠尾静脉注射L1210细胞存活时间长,适合长期观察或周期比较长的实验;DBA/2小鼠尾静脉注射L1210细胞存活时间短,但实验现象明显。后期研究可以针对不同的研究目的和实验周期来选择合适的实验模型。     

蕲蛇酶抗小鼠实验性肿瘤转移作用研究

目的：探讨从尖吻蝮蛇毒中分离得到的具有凝血酶样酶活性的蕲蛇酶抗实验性肿瘤转移作用。方法：用尾静脉注射体外培养的黑色素瘤Ｂ１６和肉瘤Ｓ－１８０细胞的小鼠肺转移模型,注射瘤细胞前后分别腹腔注射药物,２０天后处死小鼠,计数肺表面转移瘤结节数。结果蕲蛇酶剂量在２－５ＡＵ／ｋｇｉｐ能明显减少Ｂ１６在Ｃ５７ＢＬ小鼠及Ｓ－１８０在昆明鼠的肺转移结节数,但对转移瘤小鼠的生命无明显的延长作用。结论蕲蛇酶具有抗小鼠实     

STAT3小分子抑制剂FLLL31对卵白蛋白致敏小鼠气道炎症治疗活性的初步研究

目的:研究新结构化合物FLLL31抑制卵白蛋白(OVA)致敏引发的小鼠气道炎症的活性,探讨FLLL31治疗哮喘的初步疗效。方法:雄性BALB/c小鼠(18~20 g)随机分为4组,每组10只,包括正常对照组(Control组)、模型对照组(OVA组)、地塞米松组(1 mg/kg,腹腔注射)和FLLL31组(15 mg/kg,口服灌胃)。各组小鼠分别于第0 d和第14 d致敏,每只鼠腹腔注射20μg OVA和2.25 mg Al(OH)3凝胶,FLLL31自致敏第24 d开始给药,给药周期为7 d;于第28、29、30 d以气管滴入OVA进行攻击,攻击前1 h给予受试化合物FLLL31及阳性药地塞米松。结果:小鼠肺灌流液炎症细胞分类计数、肺组织病理分析等实验结果证明,FLLL31以15 mg/kg连续给药7 d后,与模型组相比,抑制了小鼠肺部气道中炎症细胞的浸润,明显改善OVA致敏引发的小鼠气道炎症症状;ELISA结果证明FLLL31降低小鼠肺灌流液中炎症因子白细胞介素6的含量;免疫组化结果显示FLLL31降低OVA致敏小鼠肺部白细胞介素6受体浓度,减少中性粒细胞标志物淋巴细胞抗原6G(Ly6G)的表达(P0.05)。结论:特异抑制STAT3的新结构化合物FLLL31在体内对OVA致敏小鼠模型气道炎症有较好的改善和免疫调节活性。     

小鼠动物实验方法系列专题(六) 卵清蛋白诱导129Sv小鼠建立哮喘模型的方法

近年来,哮喘发病率有逐年增长的趋势,因此利用动物模型研究哮喘发生的分子生物学机制及治疗方案具有重要的意义。利用卵清蛋白(ovalbumin,OVA)致敏诱导动物发生哮喘是比较成熟的方法。常用的实验动物有小鼠、大鼠、豚鼠、家兔等。该文主要介绍一种可以有效致敏129Sv品系小鼠、建立哮喘疾病模型的技术路线,并对模型指标进行了具体的描述,供从事相关研究的人员参考。     

杨树花粉致敏豚鼠过敏模型的建立

目的建立杨树花粉粗提物致敏激发的豚鼠过敏模型。方法 36只豚鼠随机分为正常组、卵清蛋白(OVA)阳性对照组和模型组,每隔5天经腹腔注射致敏1次,共3次,末次致敏后第5天雾化吸入激发。瑞氏染色观察支气管肺泡灌洗液(BAIF)中炎症细胞变化,电脑视频计数200个细胞中嗜酸性粒细胞数目;常规病理切片HE染色观察鼻黏膜、与肺的炎症情况;免疫组化法检测肺组织中IL-4及IFN-γ阳性细胞平均光密度值;酶联免疫吸附试验检测血清中的总IgE、HIS、LTB4、IL-4及IFN-γ水平。结果与正常组比较,OVA对照组、模型组均可诱导鼻黏膜及肺组织出现明显的变应性炎症;BALF涂片显示明显的炎症细胞(嗜酸性粒细胞、中性粒细胞)增多;肺组织中IL-4阳性细胞平均光密度值均高于正常组,IFN-γ阳性细胞平均光密度值均低于正常组;血清中总IgE、HIS、LTB4、IL-4均高于正常组;血清中IFN-γ则显著低于正常组。结论杨树花粉粗提物能够成功建立豚鼠过敏模型。该模型的建立有利于过敏性疾病机制的研究。     

The presence of LPS in OVA inhalations affects airway inflammation and AHR but not remodeling in a rodent model of asthma

Ovalbumin (OVA) is the most frequently used allergen in animal models of asthma. Lipopolysaccharide (LPS) contaminating commercial OVA may modulate the evoked airway inflammatory response to OVA. However, the effect of LPS in OVA on airway remodeling, especially airway smooth muscle (ASM) has not been evaluated. We hypothesized that LPS in commercial OVA may enhance allergen-induced airway inflammation and remodeling. Brown Norway rats were sensitized with OVA on day 0. PBS, OVA, or endotoxin-free OVA (Ef-OVA) was instilled intratracheally on days 14, 19, 24. Bronchoalveolar lavage (BAL) fluid, lung, and intrathoracic lymph node tissues were collected 48 h after the last challenge. Immunohistochemistry for α-smooth muscle actin, Periodic-Acid-Schiff staining, and real-time qPCR were performed. Airway hyperresponsiveness (AHR) was also measured. BAL fluid macrophages, eosinophils, neutrophils, and lymphocytes were increased in OVA-challenged animals, and macrophages and neutrophils were significantly lower in Ef-OVA-challenged animals. The ASM area in larger airways was significantly increased in both OVA and Ef-OVA compared with PBS-challenged animals. The mRNA expression of IFN-γ and IL-13 in lung tissues and IL-4 in lymph nodes was significantly increased by both OVA and Ef-OVA compared with PBS and were not significantly different between OVA and Ef-OVA. Monocyte chemoattractant protein (MCP)-1 in BAL fluid and AHR were significantly increased in OVA but not in Ef-OVA. LPS contamination in OVA contributes to the influx of macrophages and MCP-1 increase in the airways and to AHR after OVA challenges but does not affect OVA-induced Th1 and Th2 cytokine expression, goblet cell hyperplasia, and ASM remodeling.     

Acinetobacter baumannii infection inhibits airway eosinophilia and lung pathology in a mouse model of allergic asthma

Allergic asthma is a dysregulation of the immune system which leads to the development of Th2 responses to innocuous antigens (allergens). Some infections and microbial components can re-direct the immune response toward the Th1 response, or induce regulatory T cells to suppress the Th2 response, thereby inhibiting the development of allergic asthma. Since Acinetobacter baumannii infection can modulate lung cellular and cytokine responses, we studied the effect of A. baumannii in modulating airway eosinophilia in a mouse model of allergic asthma. Ovalbumin (OVA)-sensitized mice were treated with live A. baumannii or phosphate buffered saline (PBS), then intranasally challenged with OVA. Compared to PBS, A. baumannii treatment significantly reduced pulmonary Th2 cytokine and chemokine responses to OVA challenge. More importantly, the airway inflammation in A. baumannii-treated mice was strongly suppressed, as seen by the significant reduction of the proportion and the total number of eosinophils in the bronchoalveolar lavage fluid. In addition, A. baumannii-treated mice diminished lung mucus overproduction and pathology. However, A. baumannii treatment did not significantly alter systemic immune responses to OVA. Serum OVA-specific IgE, IgG1 and IgG2a levels were comparable between A. baumannii- and PBS-treated mice, and tracheobronchial lymph node cells from both treatment groups produced similar levels of Th1 and Th2 cytokines in response to in vitro OVA stimulation. Moreover, it appears that TLR-4 and IFN-γ were not directly involved in the A. baumannii-induced suppression of airway eosinophilia. Our results suggest that A. baumannii inhibits allergic airway inflammation by direct suppression of local pulmonary Th2 cytokine responses to the allergen.     

不同浓度卵蛋白变应原对小鼠哮喘模型建立的影响

目的研究不同浓度卵蛋白(ovalbumin,OVA)变应原对小鼠的哮喘造模影响。方法 96只6～8周龄SPF级雌性BALB/c小鼠随机分为8组,分别为PBS组(对照组)、10μg组(A组)、20μg组(B组)、50μg组(C组)、100μg组(D组)、200μg组(E组)、500μg组(F组)、1000μg组(G组)。A～G组分别用含1%明矾的PBS配制相应浓度的OVA于第0、7和第14天对小鼠进行腹腔注射。于第21～27天连续7 d用含1%的OVA的PBS溶液雾化吸入激发各组小鼠。正常对照组使用PBS溶液致敏和激发。最后一次雾化吸入激发后24 h内,计数各组小鼠支气管肺泡灌洗液(BLAF)中嗜酸性粒细胞的含量,ELISA法检测IL-4、IL-5的分泌量及其血清IgG2a、IgE抗体的水平;肺组织病理切片观察各组小鼠哮喘模型的效果,评价最优哮喘造模的OVA浓度。结果 A～G组小鼠肺泡灌洗液中IL-4、IL-5含量均高于正常对照组(P<0.01),细胞因子水平随着OVA浓度的增高而逐渐下降;A～G组小鼠肺泡灌洗液中嗜酸性粒细胞数均高于正常对照组(P<0.01),从低浓度组至高浓度组嗜酸性粒细胞数从高向低变化;A～G组小鼠血清中总抗体IgE的水平均显著高于正常对照组(P<0.01),且随着OVA浓度的增高IgE水平逐渐下降。血清中IgG2a的水平则随OVA给药浓度的增高而逐渐增高;低浓度OVA致敏组小鼠肺组织标本可观察到明显的炎症浸润性病理表现,而高浓度组肺部组织病理变化不明显。结论低浓度的OVA连续致敏小鼠造成过敏性哮喘病理改变较为明显,随着OVA浓度的增高,造模效果逐渐降低,而高浓度的OVA则会导致模型小鼠发生免疫耐受。     

Flt-3 ligand reverses late allergic response and airway hyper-responsiveness in a mouse model of allergic inflammation

Flt3 ligand (Flt3-L) is a growth factor for dendritic cells and induces type 1 T cell responses. We recently reported that Flt3-L prevented OVA-induced allergic airway inflammation and suppressed late allergic response and airway hyper-responsiveness (AHR). In the present study we examined whether Flt3-L reversed allergic airway inflammation in an established model of asthma. BALB/c mice were sensitized and challenged with OVA, and AHR to methacholine was established. Then mice with AHR were randomized and treated with PBS or 6 microg of Flt3-L i.p. for 10 days. Pulmonary functions and AHR to methacholine were examined after rechallenge with OVA. Treatment with Flt3-L of presensitized mice significantly suppressed (p < 0.001) the late allergic response, AHR, bronchoalveolar lavage fluid total cellularity, absolute eosinophil counts, and inflammation in the lung tissue. There was a significant decrease in proinflammatory cytokines (TNF-alpha, IL-4, and IL-5) in bronchoalveolar lavage fluid, with a significant increase in serum IL-12 and a decrease in serum IL-5 levels. There was no significant effect of Flt3-L treatment on serum IL-4 and serum total IgE levels. Sensitization with OVA significantly increased CD11b(+)CD11c(+) cells in the lung, and this phenomenon was not significantly affected by Flt3-L treatment. These data suggest that Flt3-L can reverse allergic airway inflammation and associated changes in pulmonary functions in murine asthma model.     

CC chemokine receptor-2 is not essential for the development of antigen-induced pulmonary eosinophilia and airway hyperresponsiveness

Monocyte chemoattractant proteins-1 and -5 have been implicated as important mediators of allergic pulmonary inflammation in murine models of asthma. The only identified receptor for these two chemokines to date is the CCR2. To study the role of CCR2 in a murine model of Ag-induced asthma, we compared the pathologic and physiological responses of CCR2(-/-) mice with those of wild-type (WT) littermates following immunization and challenge with OVA. OVA-immunized/OVA-challenged (OVA/OVA) WT and CCR2(-/-) mice developed significant increases in total cells recovered by bronchoalveolar lavage (BAL) compared with their respective OVA-immunized/PBS-challenged (OVA/PBS) control groups. There were no significant differences in BAL cell counts and differentials (i.e., macrophages, PMNs, lymphocytes, and eosinophils) between OVA/OVA WT and CCR2(-/-) mice. Serologic evaluation revealed no significant difference in total IgE and OVA-specific IgE between OVA/OVA WT mice and CCR2(-/-) mice. Lung mRNA expression and BAL cytokine protein levels of IL-4, IL-5, and IFN-gamma were also similar in WT and CCR2(-/-) mice. Finally, OVA/OVA CCR2(-/-) mice developed increased airway hyper-responsiveness to a degree similar to that in WT mice. We conclude that following repeated airway challenges with Ag in sensitized mice, the development of Th2 responses (elevated IgE, pulmonary eosinophilia, and lung cytokine levels of IL-4 and IL5) and the development of airway hyper-responsiveness are not diminished by a deficiency in CCR2.     

CD8+ T cells modulate late allergic airway responses in Brown Norway rats.

To test the hypothesis that CD8+ T cells may suppress the allergen-induced late airway response (LAR) and airway eosinophilia, we examined the effect of administration of Ag-primed CD8+ T cells on allergic airway responses, bronchoalveolar lavage (BAL) leukocytes, and mRNA expression for cytokines (IL-4, IL-5, and IFN-gamma) in OVA-sensitized Brown Norway rats. On day 12 postsensitization to OVA, test rats were administered 2 million CD8+ T cells i.p. isolated from either the cervical lymph nodes (LN group; n = 8) or the spleen (Spl group; n = 6) of sensitized donors. On day 14, test rats were challenged with aerosolized OVA. Control rats were administered PBS i.p. on day 12, and challenged with OVA (n = 10) or BSA (n = 6) on day 14. The lung resistance was measured for 8 h after challenge. BAL was performed at 8 h. Cytospin slides of BAL were analyzed for major basic protein by immunostaining and for cytokine mRNA by in situ hybridization. The LAR was significantly less in the LN group (1.8 +/- 0.5 U; p < 0.01) and BSA controls (1.4 +/- 0.7; p < 0.01), but not in the Spl group (6.7 +/- 2.2), compared with that in OVA controls (8.1 +/- 1.8). In BAL, the number of major basic protein-positive cells was lower in the LN and Spl groups compared with OVA controls (p < 0.05 and p < 0.01). IL-4- and IL-5-positive cells were decreased in the LN group compared with the OVA controls (p < 0.01). INF-gamma-positive cells were increased in the LN and Spl groups compared with the OVA controls (p < 0.01). Serum OVA-specific IgE levels were unaffected by CD8+ T cell transfers. These results indicate that Ag-primed CD8+ T cells have a potent suppressive effect on LAR.     

Zinc Suppressed the Airway Inflammation in Asthmatic Rats: Effects of Zinc on Generation of Eotaxin, MCP-1, IL-8, IL-4, and IFN-γ

Airway epithelium is rich in labile zinc (Zn), which may have an important protective role in the airway epithelium. The aim of this study is to investigate the effects of Zn on the airway inflammation and the generation of eotaxin, monocyte chemoattractant protein-1 (MCP-1), interleukin-8 (IL-8), interleukin-4 (IL-4), and interferon-?? (IFN-??) in rat models of ovalbumin (OVA)-induced allergic airway inflammation. For this purpose, animal model of asthma was established by OVA challenge and zinc-deficient and zinc-supplemented diets were given. Thirty-two Sprague?CDawley rats were divided into four groups: zinc-deficient diet with OVA treatment group, zinc-supplemented diet with OVA treatment group, zinc-normal diet with OVA treatment group, and zinc-normal diet with saline treatment group. Twenty-four hours after asthma was induced, lung histomorphological changes, cells in bronchoalveolar lavage fluid (BALF), contents of eotaxin, MCP-1, and IL-8 in BALF, and the expression of IFN-?? and IL-4 mRNAs were observed. Compared with the group of zinc-normal diet with OVA challenge rats, the group of zinc-deficient rats had higher numbers of eosinophils, neutrophils, and monocytes in BALF, as well as higher contents of eotaxin and MCP-1 in BALF and lower expression of lung IFN-?? mRNA. Conversely, Zn supplementation would decrease the numbers of eosinophils, neutrophils, and monocytes in BALF; suppress eotaxin and MCP-1 protein secretion; and increase lung IFN-?? mRNA expression. No significant difference was observed in IL-8 and IL-4 among OVA-challenged rats with different zinc diets. These studies suggested that Zn may be an important anti-inflammatory mediator of airway inflammation.     

咪喹莫特对慢性哮喘模型小鼠肺组织中基质金属蛋白酶-9-表达的影响

目的：观察Toll样受体7配体咪喹莫特对慢性哮喘小鼠模型气道重塑及肺组织中基质金属蛋白酶MMP-9表达的影响。方法：36只BALB／c小鼠按随机原则分成正常对照组、哮喘模型组、咪喹莫特组,每组12只。通过卵蛋白致敏,气道激发8周,末次激发24h后,检测各组小鼠气道反应性,HE染色观察气道炎症变化;Masson三色染色观察气道纤维化的改变;real-timePCR和western—blot分别检测肺组织中MMP-9的mRNA和蛋白表达。结果：慢性哮喘组小鼠气道炎症、气道高反应性和气道重塑较正常对照小鼠明显加重,而咪喹莫特组小鼠模型的气道炎症和气道反应性及气道重塑均较哮喘模型组小鼠减少或降低。慢性哮喘组小鼠肺组织MMP-9的mRNA和蛋白水平均较正常对照小鼠明显增加（P〈0．05）,而咪喹莫特治疗可显著降低哮喘小鼠肺组织MMP-9的mRNA和蛋白水平（P〈0．05）。结论：咪喹莫特能够显著抑制慢性哮喘小鼠模型的气道炎症、降低气道高反应性并减轻气道重塑,这可能与其抑制MMP-9的表达有关。     

Heme oxygenase attenuates allergen-induced airway inflammation and hyperreactivity in guinea pigs

Heme oxygenase (HO), the heme-degrading enzyme, has shown anti-inflammatory effects in several models of pulmonary diseases. HO is induced in airways during asthma; however, its functional role is unclear. Therefore, we evaluated the role of HO on airway inflammation [evaluated by bronchoalveolar lavage (BAL) cellularity and BAL levels of eotaxin, PGE(2), and proteins], mucus secretion (evaluated by analysis of MUC5AC gene expression and periodic acid-Schiff staining), oxidative stress (evaluated by quantification of 4-hydroxynonenal adducts and carbonylated protein levels in lung homogenates), and airway responsiveness to histamine in ovalbumin (OVA)-sensitized and multiple aerosol OVA or saline-challenged guinea pigs (6 challenges, once daily, OVA group and control group, respectively). Airway inflammation, mucus secretion, oxidative stress, and responsiveness were significantly increased in the OVA group compared with the control group. HO upregulation by repeated administrations of hemin (50 mg/kg i.p.) significantly decreased airway responsiveness in control animals and airway inflammation, mucus secretion, oxidative stress, and responsiveness in OVA animals. These effects were reversed by the concomitant administration of the HO inhibitor tin protoporphyrin-IX (50 micromol/kg i.p.). Repeated administrations of tin protoporphyrin-IX alone significantly increased airway responsiveness in control animals but did not modify airway inflammation, mucus secretion, oxidative stress, and responsiveness in OVA animals. These results suggest that upregulation of the HO pathway has a significant protective effect against airway inflammation, mucus hypersecretion, oxidative stress, and hyperresponsiveness in a model of allergic asthma in guinea pigs.     

颗粒蛋白前体通过抑制IL-6表达减轻哮喘气道炎症

目的: 探究颗粒蛋白前体(PGRN)在过敏性哮喘中的作用及机制。方法: 分别在野生鼠和IL-6 缺陷鼠中设置对照组和哮喘模型组,每组8只。模型组中,在第0日和第7日致敏小鼠(腹腔注射OVA 100 μg),从第14日起连续激发8 d(5％OVA雾化吸入,30 min/d,每日1次),末次激发24 h后取标本;对照组用PBS代替OVA做相同处理。采集支气管肺泡灌洗液(BALF)进行白细胞计数和分类计数;HE染色观察肺组织病理情况;Q-PCR及ELISA检测小鼠肺匀浆、血清和BALF中细胞因子水平。用IL-13刺激A549或BEAS-2B细胞建立体外哮喘炎症模型,每组3个复孔,共4组:PBS处理组、IL-13处理组、IL-13与重组人PGRN蛋白(rhPGRN)共同处理组及p38磷酸化抑制剂(SB203508)处理组。0 min~48 h后收集细胞及上清,用Q-PCR及ELISA检测PGRN和IL-6的表达;Western blot检测p38的磷酸化。结果: 与对照组相比,哮喘组小鼠肺匀浆和BALF中PGRN均显著降低(P＜ 0.01),血清PGRN有降低的趋势,然而哮喘小鼠BALF中IL-6显著升高(P＜0.05)。与野生鼠哮喘组相比,IL-6缺陷鼠哮喘组BALF中白细胞总数降低(P＜0.05),中性粒细胞数降低(P＜0.05),PGRN显著升高(P＜0.05),肺部病理损伤也减轻。体外实验中,IL-13处理组与PBS处理组相比,PGRN显著降低(P＜0.05),IL-6显著增高(P＜ 0.05),p38的磷酸化增加;p38抑制剂处理组比未处理组中IL-6水平降低(P＜0.05)。IL-13与rhPGRN共同处理组的IL-6显著低于IL-13处理组(P＜0.05),p38的磷酸化降低(P＜0.05)。结论: PGRN通过抑制p38磷酸化降低IL-6水平从而减轻哮喘小鼠气道炎症。