阿奇霉素对哮喘致敏大鼠气道炎症及Th1/Th2失衡的调节作用

目的:探讨阿奇霉素对哮喘(OVA)致敏大鼠气道炎症及Th1/Th2失衡的调节作用。方法:SD大鼠40只,随机分为生理盐水组、哮喘模型组、地塞米松组以及阿奇霉素组,每组10只。利用卵白蛋白(Ovalbumin,OVA)/Al(OH)3致敏与OVA雾化吸入激发建立大鼠过敏性气道炎症模型,收集肺泡灌洗液(BALF)进行白细胞分类计数。采用ELISA法测定肺泡灌洗液中IL-2、IL-4、TNF-α与ET-1的表达情况。光镜观察肺组织病理结构变化。结果:OVA模型大鼠肺泡灌洗液中的中性粒细胞、淋巴细胞以及嗜酸性粒细胞含量明显增加;HE染色观察肺组织病理结构出现明显的支气管上皮脱落、杯状细胞增生,支气管周围嗜酸性粒细胞明显浸润现象;BALF中IL-2、IL-4、TNF-α与ET-1的表达均明显高于生理盐水对照组(P<0.05)。阿奇霉素则显著降低肺泡灌洗液中中性粒细胞、淋巴细胞以及嗜酸性粒细胞含量;明显改善支气管上皮脱落、杯状细胞增生,支气管周围嗜酸性粒细胞浸润现象;BALF中IL-2、IL-4、TNF-α与ET-1的表达也明显低于OVA模型大鼠(P<0.05)。结论:阿奇霉素通过调节Th1/Th2失衡对过敏性哮喘的气道炎症具有明显的治疗作用。     

红霉素对支气管哮喘大鼠Clara细胞及CC16表达的影响

目的探讨红霉素对支气管哮喘(简称哮喘)大鼠模型肺组织Clara细胞数量和Clara细胞分泌蛋白-16(CC16)表达的影响。方法用卵白蛋白(OVA)致敏、激发建立大鼠哮喘模型,随机分为正常对照组、哮喘组、红霉素组、地塞米松组。收集肺泡灌洗液(BALF)进行细胞计数及分类,光镜下观察肺组织病理学变化;ELISA方法检测BALF中CC16含量,用免疫组化的方法检测肺组织中Clara细胞表达变化。结果与正常对照组相比,哮喘组大鼠支气管及血管周围、肺间质内有嗜酸性粒细胞(EOS)及其他炎性细胞浸润,黏液腺增生,黏膜皱折增多,黏膜上皮细胞脱落,可见气道黏液栓,而红霉素组和地塞米松组上述现象明显减轻。肺组织Clara细胞计数显示,哮喘组大鼠终末及呼吸性细支气管上皮Clara细胞数明显少于正常对照组,而红霉素组和地塞米松组较哮喘组均有所增加(P<0.05)。哮喘组EOS百分比(EOS%)显著高于对照组(P<0.01),红霉素组和地塞米松组的EOS%均低于哮喘组(P<0.01)。BALF中CC16含量,哮喘组明显低于正常对照组(P<0.01),而红霉素组和地塞米松组均高于哮喘组(P<0.05)。结论哮喘时肺组织中Clara细胞及CC16的表达减少,红霉素可通过上调肺组织中Clara细胞及CC16的表达来发挥抗炎作用。     

建立支气管哮喘大鼠模型的新方法及评价

目的 探讨建立支气管哮喘动物模型的新方法.方法 20只清洁级SD大鼠随机分为哮喘组和对照组,每组10只,哮喘组以小剂量卵蛋白(OVA)1 mg致敏并激发为大鼠哮喘模型,对照组以氢氧化铝凝胶致敏,以0.9％氯化钠溶液激发.观察2组大鼠肺组织病理、支气管肺泡灌洗液(BALF)细胞分类及血清OVA-specific IgE水...     

黄芪多糖对哮喘大鼠Th17/Treg细胞因子及肺部炎症的影响

目的 观察黄芪多糖(astragalus polysaccharide,APS)对哮喘大鼠支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF))中IL-17A、IL-25、IL-35、IL-10水平及肺部炎症的影响,探讨其对哮喘的治疗作用及其机制.方法 实验分为正常组、模型组、黄芪多糖组.通过OVA腹腔注射致敏及OVA雾化吸入激发制备哮喘大鼠模型.采用肺组织HE染色评价大鼠肺部炎症;瑞氏染色检测BALF中炎症细胞总数及分类;电镜观察Ⅱ型肺泡上皮细胞超微结构的变化;酶联免疫技术检测BALF中Th17细胞因子IL-17A、IL-25以及Treg细胞因子IL-35、IL-10的水平.结果 哮喘组大鼠肺组织炎症表现显著,Ⅱ型肺泡上皮超微结构损伤明显,BALF中IL-17A、IL-25含量明显升高(P<0.05),而IL-35、IL-10含量明显降低(P<0.05).APS干预降低可BALF中炎症细胞总数、淋巴细胞、嗜酸性粒细胞以及巨噬细胞数量(P<0.05),降低BALF中IL-17A、IL-25含量(P<0.05),升高IL-35、IL-10含量(P<0.05).结论 黄芪多糖治疗哮喘的机制可能与调节哮喘机体Th17/Treg细胞因子间的平衡有关.     

咳喘凝胶贴膏穴位敷贴对支气管哮喘大鼠炎症因子的影响

摘要：目的:通过观察支气管哮喘模型大鼠炎症因子的变化,探讨咳喘凝胶贴膏对支气管哮喘的治疗作用。方法:50只SD大鼠随机分为正常对照组、哮喘模型组、地塞米松组、咳喘凝胶贴膏药物组、假穴位组,每组10只。采用卵蛋白（OVA）致敏和雾化吸入激发的方法建立支气管哮喘大鼠模型。建模成功后,正常对照组大鼠和哮喘模型组给予生理盐水灌胃;地塞米松组大鼠给予地塞米松混悬液1 mg·kg-1·d-1灌胃;咳喘凝胶贴膏组及假穴位敷贴组于肺腧、肾腧穴分别给予药物和空白基质进行穴位给药,1次/d,每侧面积约为2 cm×2 cm,共2周。在末次激发24 h后收集支气管肺泡灌洗液（BALF）,光学显微镜下进行大鼠肺泡灌洗液嗜酸性粒细胞（EOS）计数,采用酶联免疫法检测大鼠白细胞介素-17（IL-17）、白细胞介素-1（IL-1β）、白细胞介素-13（IL-13）水平。结果:OVA成功诱导支气管哮喘模型;与正常对照组相比,模型组和假穴位组大鼠EOS计数、IL-17、IL-1β、IL-13水平均显著升高（P<0.05或P<0.01）;与模型组相比,地塞米松组、咳喘凝胶贴膏药物组均能显著降低EOS数量、IL-17、IL-1β、IL-13水平（P<0.05或P<0.01）;地塞米松组与咳喘凝胶贴膏药物组各指标比较差异无统计学意义（P>0.05）。结论:咳喘凝胶贴膏可降低OVA诱发哮喘大鼠EOS数量,影响IL-17、IL-1β、IL-13表达水平。     

罗红霉素对哮喘大鼠髓样相关蛋白-8表达的影响

目的探讨罗红霉素对哮喘大鼠髓样相关蛋白-8(MRP8)表达水平及哮喘气道炎症的影响。方法将18只雄性SPF级Brown Norway(BN)大鼠,按照随机数字表法分为正常对照组(C组)6只、哮喘组(A组)6只及罗红霉素治疗组(R组)6只。分别通过卵清白蛋白(OVA)+弗式完全佐剂(FCA)联合致敏,OVA雾化激发构建大鼠哮喘模型,R组用罗红霉素干预。观察各组大鼠肺组织病理结构变化,分析支气管肺泡灌洗液(BALF)中细胞分类计数,酶联免疫吸附试验(ELISA)法检测各组大鼠BALF MRP8水平;蛋白质印迹法测定肺组织MRP8的表达,Pearson相关性分析MRP8与各细胞分类计数的关系。结果 R组BALF细胞总数、嗜酸性粒细胞百分比(EOS%)及中性粒细胞百分比(NEU%)明显高于C组,但低于A组(P均<0.05);R组BALF中白细胞介素(IL)-17、MRP8及肺组织MRP8均高于C组,但低于A组(P均<0.05);Pearson相关性分析显示BALF及肺组织的MRP8水平与BALF细胞总数、EOS%、NEU%、IL-17比例均呈正相关(P均<0.01)。结论急性哮喘大鼠BALF及肺组织MRP8水平升高,并与气道炎症呈正相关,罗红霉素可以通过降低哮喘大鼠MRP8的表达改善哮喘症状。     

咪喹莫特对哮喘小鼠气道炎症和调节性T细胞的影响

目的:观察咪喹莫特对小鼠哮喘模型气道炎症和调节性T细胞Foxp3表达的影响。方法:建立哮喘模型,第0、7、14天分别腹腔注射卵白蛋白(OVA)及其佐剂,自21 d时开始雾化吸入OVA一次,连续7 d,吸入OVA前0.5 h,咪喹莫特组雾化吸入咪喹莫特30 min(1.5 g/L),地塞米松组腹腔注射地塞米松(4 mg/kg)。最后一次OVA雾化吸入后48 h取左下肺组织做HE染色观察肺组织炎症改变;收集支气管肺泡灌洗液(BALF)进行细胞计数、分类和ELISA检测。结果:(1)HE染色显示咪喹莫特组小鼠肺组织炎症程度较哮喘小鼠轻。(2)哮喘组小鼠BALF中嗜酸性粒细胞较正常组显著增加(P<0.01),咪喹莫特组嗜酸性粒细胞比哮喘组显著减少(P<0.01)。(3)哮喘组BALF中IL-5水平较正常组显著升高(P<0.01),咪喹莫特治疗组比哮喘组显著降低(P<0.01)。哮喘组BALF中IL-10水平较正常组显著降低(P<0.01),咪喹莫特治疗组比哮喘组显著升高(P<0.05)。(4)哮喘组脾脏组织Foxp3+细胞数量较正常组减少,咪喹莫特组与地塞米松组较哮喘组增加(P<0.01)。结论:雾化吸入咪喹莫特可在一定程度上增加Foxp3+细胞数量,减轻哮喘小鼠的气道炎症。     

骨形态构建蛋白 2型受体下调单核细胞趋化蛋白 1/CC类趋化因子受体 2通路对哮喘小鼠气道炎症和 Th1/Th2平衡的影响

目的探究骨形态构建蛋白 2型受体( BMPR2)对小鼠哮喘模型气道炎症和 Th1/Th2平衡的影响及其机制。方法2021年 9月至 2022年 11月选用 24只 C57BL/6小鼠尾静脉注射 BMPR2腺病毒,随后卵清蛋白( OVA)致敏和激发建立哮喘小鼠于模型;采用随机数字表法分为对照组(生理盐水替代 OVA造模)、 OVA模型组( OVA诱导小鼠哮喘模型)、 OVA+载体( Vector)组(空载慢病毒处理的 OVA哮喘模型小鼠)OVA+BMPR2组( BMPR2过表达慢病毒处理的 OVA哮喘模型小鼠),每组 6只。收集支气管肺泡灌洗液( BALF)和肺组织。免疫、组织化学检测肺组织 BMPR2表达水平;苏木精 -伊红染色观察肺组织病理学改变;瑞氏染色后计数 BALF中各类炎症细胞数目;酶联免疫吸附测定( ELISA)试剂盒检测 BALF中白细胞介素( IL)-4,IL-5和 IL-13炎症因子水平;蛋白质印迹法检测肺组织和气道上皮细胞 16HBE中 BMPR2、单核细胞趋化蛋白 -1(MCP1)及其受体 CC类趋化因子受体 2(CCR2)蛋白表达水平。免疫共沉淀实验检测 BMPR2与 MCP1相互作用。结果与对照组相比, OVA模型组肺组织 BMPR2(0.36±0.05比 1.04±0.04)显著降低(P<0.01);小鼠肺泡破坏程度严重,肺组织有大量的淋巴细胞浸润; BALF中炎症细胞总数［(93.25±9.32)×104个/毫升比( 4.79±0.41)×104个/毫升, P<0.001］、嗜酸性粒细胞、中性粒细胞和淋巴细胞均升高; Th1相关炎症因子 γ干扰素( IFN-γ)水平降低, Th2相关炎症因子 IL-4,IL-5和 IL-13水平升高。过表达 BMPR2可降低肺泡破坏程度和淋巴细胞浸润程度。与 OVA+Vector组相比, OVA+BMPR2组 BALF中炎症细胞总数、嗜酸性粒细胞、中性粒细胞和淋巴细胞均降低; ELISA结果表明, OVA+BMPR2组 BALF中 IFN-γ水平升高, IL-4,IL-5和 IL-13水平降低,提示过表达 BMPR2可上调 Th1百分比,下调 Th2细胞百分比。进一步研究表明, BMPR2过表达显著下调了 MCP1及其受体 CCR2的表达水平,且 BMPR2与MCP1存在相互作用。结论 BMPR2可通过下调 MCP1/CCR2通路降低哮喘小鼠气道炎症,并调节 Th1/Th2平衡。     

哮喘大鼠肺泡巨噬细胞IL-6及TNF-α的表达水平及其意义

目的调查哮喘大鼠肺泡巨噬细胞IL-6和TNF-αmRNA表达水平的变化及其在哮喘发病中的作用。方法利用卵蛋白(ovialbumin,OVA)致敏并激发大鼠建立哮喘模型,对照组则用生理盐水代替;收集支气管肺泡灌洗液(bronchusalveolar lavage fluid,BALF)并用RMPI1640培养AM。各组细胞在利用LPS(5μg.ml-1)处理12小时前后,通过RT-PCR技术检测肺泡巨噬细胞中IL-6和TNF-αmRNA的表达水平。结果病理学检测发现哮喘模型组(n=7)炎症细胞浸润明显增加,支气管肺泡灌洗液(BALF)细胞总数显著增高,与对照组(n=7)比较差异显著(P<0.01)。两组肺泡巨噬细胞经LPS处理后,IL-6和TNF-αmRNA的表达水平明显增高(n=7,P<0.01)。无论LPS处理与否,哮喘组肺泡巨噬细胞IL-6的表达水平与对照组相比明显增高(n=7,P<0.01);TNF-α的表达水平变化情况与IL-6相似,但其显著性不及IL-6高(n=7,P<0.05)。结论哮喘大鼠肺泡巨噬细胞IL-6和TNF-αmRNA的表达水平与对照组相比明显增高。由此可见,哮喘大鼠的肺泡巨噬细胞被激活并且产生IL-6和TNF-α从而参与哮喘的发生发展。     

致敏大鼠大脑皮层和肺组织中白三烯B4含量一致性升高

目的:检测大鼠哮喘模型脑皮层和肺组织中白三烯(LT)的含量变化,以及抗哮喘药物对该变化的影响。方法:卵白蛋白致敏大鼠,观察支气管肺泡灌洗液(BALF)和肺组织及脑组织切片的炎症性变化,同时用反向高效液相(RP-HPLC)方法检测肺组织及大脑皮层匀浆LT的含量变化。结果:哮喘大鼠BALF内炎症细胞数量和组织学检查评分显著高于正常对照组(P<0.05),地塞米松(DXM,0.5mg/kg)和富马酸酮替芬(KF,5mg/kg)减轻这些炎症变化,RP-HPLC发现在哮喘大鼠肺组织及大脑皮层匀浆中LTB_4含量比正常大鼠显著升高(P<0.05),DXM和KF均可减低肺组织及大脑皮层匀浆液中的LTB_4水平,LTC_4在哮喘大鼠肺组织匀浆液中的含量较正常组显著升高(P<0.05),脑皮层内的含量无变化,DXM和KF均可降低哮喘大鼠肺组织匀浆液中LTC_4的水平(P<0.05)。结论:哮喘大鼠抗原攻击后脑皮层和肺组织中的LTB_4含量都一致性升高,DXM和KF可抑制这种变化。     

布地奈德对哮喘大鼠碱性成纤维细胞生长因子蛋白和mRNA表达的影响

目的：观察碱性成纤维细胞生长因子在急性哮喘大鼠肺组织的表达情况及布地奈德的干预影响.方法：36只雄性SD大鼠随机分为对照组、哮喘组和布地纳德治疗组,以卵清白蛋白激发法制备哮喘模型,采用ELISA法测定支气管肺泡灌洗液中碱性成纤维细胞生长因子的含量,免疫组化和原位杂交法测定肺组织中碱性成纤维细胞生长因子蛋白和mRNA的表达情况.结果：支气管肺泡灌洗液中的碱性成纤维细胞生长因子浓度、肺组织碱性成纤维细胞生长因子蛋白和mRNA的表达水平哮喘组显著高于对照组（P＜0.01）,治疗组显著低于哮喘组（P＜0.01）,但与对照组相比仍较高（P＜0.01）,上皮细胞为主要表达细胞.结论：碱性成纤维细胞生长因子参与了哮喘的发病机制,布地奈德可抑制哮喘急性期碱性成纤维细胞生长因子蛋白和mRNA的表达增加效应,这可能是布地奈德抑制哮喘气道重塑的重要机制之一.     

Therapeutic effects of anti-B7-1 antibody in an ovalbumin-induced mouse asthma model

Allergic asthma is a chronic inflammatory disorder of airways, which is characterized by attacks provoked by exposure to so-called asthma triggers, such as pet dander, second-hand tobacco smoke, dust mites, and mold spores. B7-1 (CD80), perhaps one of the most studied co-stimulatory molecules involved in asthma, plays a key role in regulating allergen-induced T cell activation in asthma, probably through T cell recruitment and Th cell differentiation upon allergen provocation. The present study was designed to test the hypothesis that anti-B7-1 antibody has therapeutic effects in asthma by blocking B7-1/CD28 pathway. The asthma model was established by ovalbumin (OVA) sensitization and challenging in female Balb/c mice. One hour after the last induction, mice were sacrificed and whole lung lavage was conducted. Cell numbers in bronchoalveolar lavage fluid (BALF) were determined and the expression levels of IFN-gamma and IL-4 in supernatant were measured by an enzyme-linked immunosorbent assay method. Sedimental cells smears were stained with Wright's-Gimsa mixed coloring method. The B7-1 expression was detected by immunohistochemistry method with frozen tissue sections. The anti-B7-1 antibody treatment could alleviate asthmatic syndromes induced by OVA. The number of recoverable eosinophils in BALF in the anti-B7-1 antibody treated group was significantly lower than that in the control group (P<0.01) and the eosinophils peribronchial infiltration was remarkably reduced in anti-B7-1 treated asthmatic mice, based on histological evaluation. The treatment with the anti-B7-1 antibody induced IFN-gamma expression and decreased IL-4 expression, compared with the asthmatic control group (P<0.01). In conclusion, the anti-B7-1 antibody approach may provide a novel therapy for allergic asthma.     

Neovastat (AE-941) inhibits the airway inflammation via VEGF and HIF-2 alpha suppression

Vascular endothelial growth factor (VEGF) contributes to airway inflammation and angiogenesis in asthma. Hypoxia inducible factor (HIF), the most potent regulator of VEGF, is a heterodimer of a constitutively expressed beta subunit and an oxygen-regulated alpha subunit (HIF-alpha). Three HIF-alpha isoforms have been described, of which HIF-2 alpha are abundantly expressed in lung tissue. Neovastat is a naturally occurring inhibitor of angiogenesis derived from marine cartilage. We previously reported that Neovastat can inhibit the airway inflammation in asthma. In this study, we hypothesized that the anti-inflammatory effect of Neovastat is mediated with inhibition of VEGF and HIF-2 alpha. BALB/c mice were immunized subcutaneously and challenged with inhaled ovalbumin (OVA). Neovastat was administrated by gavage three times with 12-h interval, beginning at 30 min before OVA inhalation. VEGF concentration in bronchoalveolar lavage fluid was measured by ELISA. We evaluate the expression of VEGF and HIF-2 alpha in lung tissue by immunohistochemistry. Mice treated with Neovastat had significantly reduced inflammatory cell count in BAL fluid compared with untreated asthmatic mice. Furthermore, Mice treated with Neovastat showed significantly reduced VEGF and HIF-2 alpha expression on lung tissue. These results suggest that anti-inflammatory effects of Neovastat could be linked to inhibition of VEGF and HIF-2 alpha.     

S-Allyl cysteine reduces eosinophilic airway inflammation and mucus overproduction on ovalbumin-induced allergic asthma model

S-Allyl cysteine (SAC) is an active component in garlic and has various pharmacological effects, such as anti-inflammatory, anti-oxidant, and anti-cancer activities. In this study, we explored the suppressive effects of SAC on allergic airway inflammation induced in an ovalbumin (OVA)-induced asthma mouse model. To induce asthma, BALB/c mice were sensitized to OVA on days 0 and 14 by intraperitoneal injection and exposed to OVA from days 21 to 23 using a nebulizer. SAC was administered to mice by oral gavage at a dose of 10 or 20 mg/kg from days 18 to 23. SAC significantly reduced airway hyperresponsiveness, inflammatory cell counts, and Th2 type cytokines in bronchoalveolar lavage fluid induced by OVA exposure, which was accompanied by reduced serum OVA-specific immunoglobulin E. In histological analysis of the lung tissue, administration of SAC reduced inflammatory cell accumulation into lung tissue and mucus production in airway goblet cells induced by OVA exposure. Additionally, SAC significantly decreased MUC5AC expression and nuclear factor-κB phosphorylation induced by OVA exposure. In summary, SAC effectively suppressed allergic airway inflammation and mucus production in OVA-challenged asthmatic mice. Therefore, SAC shows potential for use in treating allergic asthma.     

Release of nerve growth factor by human pulmonary epithelial cells: role in airway inflammatory diseases

Elevated levels of nerve growth factor (NGF) have been detected in the bronchoalveolar lavage fluid of patients with asthma. However, the source of this enhanced mediator production is not known. Here, we investigate the production of NGF from a human airway epithelial cell line (A549). Under basal conditions, A549 cells generated NGF in a time-dependent fashion. However, basal release was significantly augmented in a concentration-dependent manner in cells treated with interleukin-1beta (IL-1beta) or tumour necrosis factor-alpha (TNF-alpha) and inhibited by dexamethasone. These data suggest that NGF released from structural cells may be an important target for the anti-inflammatory effects of steroids in asthma therapy.     

Sitagliptin exerts anti-inflammatory and anti-allergic effects in ovalbumin-induced murine model of allergic airway disease

Sitagliptin, a new oral glucose lowering medication, is used for treatment of type 2 diabetes mellitus. The anti-inflammatory property of sitagliptin is reported, yet no studies have been done on asthma. In the present study, the effect of sitagliptin on allergic asthma was investigated using ovalbumin (OVA)-induced asthma model in mice. Swiss male albino mice sensitized and challenged to ovalbumin were treated with sitagliptin (8?mg/kg administered orally twice a day). Drug treatment was done on each day from days 16 to 23, 1?h before the challenge on the days of challenge. Sitagliptin treatment markedly decreased inflammatory cell accumulation in bronchoalveolar lavage (BAL) fluid and in the lungs, as revealed by histopathological examination. Furthermore, the levels of interleukin (IL)-13 in BAL fluid, total and OVA specific immunoglobulins (Ig)-E in serum, were significantly reduced as compared to the OVA group. In addition, sitagliptin significantly increased superoxidase dismutase (SOD) and reduced glutathione (GSH) activities with significant decrease in malondialdehyde (MDA) content in the lung. Importantly, sitagliptin decreased mRNA expression of the inflammatory cytokines tumor necrosis factor-α (TNF-α) and transforming growth factor-β(1) (TGF-β(1)) in lung tissues as compared to the OVA group. Moreover, nitric oxide content as well as the mRNA expression of inducible nitric oxide synthase (iNOS) was remarkably decreased by sitagliptin treatment. Sitagliptin attenuates the allergic airway inflammation suggesting that sitagliptin may have applications in the treatment of bronchial asthma.     

Anti-allergic activity of a Kampo (Japanese herbal) medicine "Sho-seiryu-to (Xiao-Qing-Long-Tang)" on airway inflammation in a mouse model

Effects of a Kampo (Japanese herbal) medicine "Sho-seiryu-to (SST, Xiao-Qing-Long-Tang in Chinese)", which has been used for the treatment of allergic bronchial asthma clinically, were examined on ovalbumin (OVA)-sensitized allergic airway inflammation model (i.e., bronchial asthma) in a mouse. When SST was orally administered at 0.5 g/kg/day from day 1 to 6 days after OVA inhalation, SST reduced the OVA-specific IgE antibody titer in bronchoalveolar lavage (BAL) fluids at 7 days after the OVA inhalation. CD4(+) T cells obtained from the mouse lung produced more interleukin (IL)-4 and IL-5 but less interferon (IFN)-gamma than T cells from nonsensitized control animals. However, oral administration of SST reduced the production of IL-4 and IL-5 and the production of IFN-gamma returned to the control level. In addition, the IL-4 level was increased in the BAL fluid of the OVA-sensitized animals compared to the nonsensitized control, while the IFN-gamma levels decreased. SST reduced the IL-4 levels in the BAL fluids and returned the IFN-gamma level to control levels. Nerve growth factor (NGF) was increased in the BAL fluids of the OVA-sensitized mice over that of nonsensitized mice, but oral administration of SST augmented the NGF levels to approximately 2 times higher than in the sensitized mice. Although lung cells obtained from sensitized mice produced higher levels of NGF than nonsensitized mice, oral administration of SST augmented the production of NGF by the lung cells even higher ( approximately 2 times more than cells from sensitized mice). Administration of anti-NGF antibody to the airway blocked the effects of SST. These results suggest that SST modulates Th1/Th2 balance in the lungs and augmentation of NGF in the lungs may be related to the effects of SST. Pinellic acid (9S, 12S, 13S-trihydroxy-10E-octadecenoic acid), one component of the herbs of SST [Int. Immunopharmacol. 2 (2002) 1183], was purified from the tuber of Pinellia ternata Breitenbach. Oral administration of pinellic acid (50 microg/kg/day) also reduced the OVA-specific IgE antibody titer in BAL fluids from the sensitized mouse. This result suggests that pinellic acid is one of active ingredient(s) in SST.     

Reduced allergic lung inflammation in rats following formaldehyde exposure: Long-term effects on multiple effector systems

Clinical and experimental evidences show that formaldehyde (FA) exposure has an irritant effect on the upper airways. As being an indoor and outdoor pollutant, FA is known to be a causal factor of occupational asthma. This study aimed to investigate the repercussion of FA exposure on the course of a lung allergic process triggered by an antigen unrelated to FA. For this purpose, male Wistar rats were subjected to FA inhalation for 3 consecutive days (1%, 90-min daily), subsequently sensitized with ovalbumin (OVA)-alum via the intraperitoneal route, and 2 weeks later challenged with aerosolized OVA. The OVA challenge in rats after FA inhalation (FA/OVA group) evoked a low-intensity lung inflammation as indicated by the reduced enumerated number of inflammatory cells in bronchoalveolar lavage as compared to FA-untreated allergic rats (OVA/OVA group). Treatment with FA also reduced the number of bone marrow cells and blood leukocytes in sensitized animals challenged with OVA, which suggests that the effects of FA had not been only localized to the airways. As indicated by passive cutaneous anaphylactic reaction, FA treatment did not impair the anti-OVA IgE synthesis, but reduced the magnitude of OVA challenge-induced mast cell degranulation. Moreover, FA treatment was associated to a diminished lung expression of PECAM-1 (platelet-endothelial cell adhesion molecule 1) in lung endothelial cells after OVA challenge and an exacerbated release of nitrites by BAL-cultured cells. Keeping in mind that rats subjected solely to either FA or OVA challenge were able to significantly increase the cell influx into lung, our study shows that FA inhalation triggers long-lasting effects that affect multiple mediator systems associated to OVA-induced allergic lung such as the reduction of mast cells activation, PECAM-1 expression and exacerbation of NO generation, thereby contributing to the decrease of cell recruitment after the OVA challenge. In conclusion, repeated expositions to air-borne FA may impair the lung cell recruitment after an allergic stimulus, thereby leading to a non-responsive condition against inflammatory stimuli likely those where mast cells are involved.     

Montelukast modulates lung CysLT(1) receptor expression and eosinophilic inflammation in asthmatic mice

AIM: To determine the expressions of cysteinyl leukotriene receptors, CysLT1 and CysLT2, in airway eosinophilic inflammation of OVA-induced asthmatic mice and the modulation by montelukast, a CysLT1 receptor antagonist. METHODS: Asthma model was induced by chronic exposure to ovalbumin (OVA) in C57BL/6 mice. The eosino-phils in bronchoalveolar lavage (BAL) fluid and lung tissues were counted, IL-5 level in BAL fluid was measured, and CysLT1 and CysLT2 receptor mRNA expressions were detected by semi-quantitative RT-PCR. RESULTS: Montelukast (6 mg/kg, once per day for 20 d) significantly suppressed the increased eosinophils in BAL fluid and lung tissue, and increased IL-5 level in BAL fluid in OVA challenged mice. OVA challenge increased CysLT1 but decreased CysLT2 receptor mRNA expression. Montelukast inhibited the increased CysLT1 but not the reduced CysLT2 expression after OVA challenge. CONCLUSION: CysLT receptors are modulated immunologically, and montelukast inhibits up-regulation of CysLT1 receptor