TLR4/MyD88/NF-κB通路在真菌性角膜炎中的表达和作用

目的 探究Toll样受体4(TLR4)/髓样分化因子88(MyD88)/核因子κB(NF-κB)通路在真菌性角膜炎中的表达和作用。方法 选择2016年1月-2021年1月滕州市中心人民医院收治的82例(82眼)真菌性角膜炎角膜上皮组织为真菌组,另选择40例(40眼)健康角膜组织为正常组,采用免疫组化、实时荧光定量PCR(RT-PCR)和免疫印迹法检测角膜上皮中TLR4、MyD88和NF-κB蛋白表达阳性率、 mRNA及蛋白水平,酶联免疫吸附实验检测炎性细胞因子白细胞介素-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)、γ-干扰素(IFN-γ)、α-干扰素(IFN-α)水平。结果 真菌性角膜炎角膜上皮中TLR4、MyD88和NF-κB蛋白阳性表达率、mRNA及蛋白表达水平高于正常角膜上皮(P<0.05);真菌性角膜炎角膜上皮中炎性细胞因子IL-1β、TNF-α、IFN-γ、IFN-α水平高于正常角膜上皮(P<0.05);真菌性角膜炎角膜上皮中TLR4、MyD88、NF-κB mRNA及蛋白表达水平与炎性细胞因子IL-1β、TNF-α、IFN-γ、IFN-α均呈正相关(P&...     

儿童难治性支原体肺炎外周血TLR2信号通路表达及其对疗效的诊断价值

目的 探究难治性支原体肺炎(RMPP)患儿Toll样受体2(TLR2)信号通路表达及其对疗效的诊断价值。方法 选取2019年5月-2021年5月济南市妇幼保健院收治的70例RMPP患儿为RMPP组，另选取医院同期收治的70例普通支原体肺炎(MPP)患儿为MPP组。收集两组患儿的临床资料，采用实时荧光定量聚合酶链式反应(qRT-PCR)检测外周血单个核细胞(PBMC)TLR2 mRNA、髓样分化蛋白88(MyD88)mRNA、核转录因子-κB(NF-κB)mRNA相对表达水平，酶联免疫吸附法检测血清肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、IL-8、干扰素-γ(IFN-γ)、半胱氨酰白三烯(CysLTs)水平，采用受试者工作特征(ROC)曲线分析TLR2 mRNA、MyD88 mRNA、NF-κB mRNA相对表达水平对RMPP的诊断价值。根据RMPP患儿治疗后疗效将患儿分为有效组和无效组，比较治疗后7 d时TLR2 mRNA、MyD88 mRNA、NF-κB mRNA相对表达水平，并分析其表达与治疗效果的关系。结果 RMPP组的TLR2 mRNA、MyD88 mRNA...     

TLR4/MyD88/NF-κB信号通路在萎缩性胃炎伴幽门螺杆菌感染中的作用

目的 探讨Toll样受体4(TLR4)/髓样分化因子88(MyD88)/核因子κB(NF-κB)信号通路在萎缩性胃炎伴幽门螺杆菌感染中的作用及临床意义。方法 选取2019年6月-2021年5月在徐州市中心医院消化内科接受治疗的118例萎缩性胃炎伴幽门螺杆菌感染患者作为胃炎组,根据慢性胃炎的内镜分型分级标准中的萎缩性胃炎分类标准分为Ⅰ级、Ⅱ级、Ⅲ级,同时选择40名健康人作为对照组。酶联免疫吸附法检测两组血清中TLR4、MyD88、NF-κB以及白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)炎性因子的表达水平。应用受试者工作特征曲线(ROC曲线)分析TLR4、MyD88和NF-κB对萎缩性胃炎伴幽门螺杆菌感染的预测价值。结果 与对照组比较,研究组患者TLR4、MyD88及NF-κB的表达量均增高(P<0.05);炎性因子IL-1β、IL-6、TNF-α的表达水平高于对照组(P<0.05);血清TLR4、MyD88和NF-κB联合预测萎缩性胃炎伴幽门螺杆菌感染的AUC为0.897,高于单独检测的0.854、0.858、0.870。结论 血清中TLR4、MyD88、NF...     

肠梗阻并发腹腔感染患者TLR4/NF-κB信号通路及其与病情转归的关系

目的 探究肠梗阻并发腹腔感染(IAI)患者外周血Toll样受体4(TLR4)/核因子κB(NF-κB)信号通路及其与病情转归的关系。方法 分别选取2018年1月-2021年6月大连大学附属中山医院肠梗阻并发IAI患者117例(感染组)和肠梗阻未合并感染患者109例(未感染组),检测外周血单个核细胞(PBMC)中TLR4 mRNA、髓样分化因子88(MyD88)mRNA和NF-κB mRNA水平及白细胞介素-4(IL-4)、IL-10和肿瘤坏死因子-α(TNF-α),同时采集基本资料并完善其他检查,根据感染程度和抗感染疗效对患者进行分组,并比较不同程度和疗效患者各项指标差异。结果 感染组PBMC中TLR4 mRNA、MyD88 mRNA和NF-κB mRNA及IL-4、IL-10与TNF-α高于未感染组(P<0.05);重度组PBMC中TLR4、MyD88和NF-κB mRNA和IL-4、IL-10及TNF-α水平高于轻中度组(P<0.05);好转组治疗3 d时PBMC中TLR4、MyD88和NF-κB mRNA及IL-4、IL-10和TNF-α均降低(P<0.05),...     

鱼腥草提取物对肺炎支原体感染大鼠的抗炎作用及其作用机制

目的 对肺炎支原体感染大鼠进行鱼腥草提取物治疗,对其所产生抗炎功效及作用机制进行分析。方法 SPF级Wistar雄性大鼠分为空白组、肺炎支原体感染模型组、鱼腥草提取物低剂量组和高剂量组各9只。空白组、模型组只进行生理盐水灌胃,低剂量组和高剂量组给予鱼腥草提取物125 mg/kg、500 mg/kg灌胃,持续7 d后检测外周血转化生长因子-β(TGF-β)、涎液化糖链抗原-6(KL-6)、表面活性蛋白D(SP-D)、炎症因子及Toll样受体4(TLR4)、髓样分化因子88(MyD88)、核因子κB(NF-κB)mRNA相对表达量,免疫印迹法检测肺组织中TLR4、MyD88、NF-κB蛋白表达。结果 与空白组比较,模型组、鱼腥草提取物低剂量组、高剂量组TGF-β、KL-6、SP-D、IL-13、TNF-α水平、TLR4、MyD88、NF-κB mRNA表达量、TLR4、MyD88、NF-κB蛋白表达量均升高,IL-12水平降低(P<0.05);与模型组、低剂量组比较,高剂量组TGF-β、KL-6、SP-D、IL-13、TNF-α水平、TLR4、MyD88、NF-κB mRNA表达量、...     

参苓白术散对感染鼠伤寒沙门菌小鼠的免疫调节作用

目的探讨参苓白术散对感染鼠伤寒沙门菌小鼠的抑菌作用及免疫调节机制。方法用鼠伤寒沙门菌标准菌株(STM,50115)制备STM小鼠模型,造模后给予小鼠参苓白术散(1 g/ml)或庆大霉素(2 mg/ml)连续灌胃10 d,观察小鼠盲肠病理改变,检测盲肠中TNF-α、IL-1β、IL-6、TLR4、MyD88、NF-κB mRNA水平及TLR4、MyD88、NF-κB蛋白含量,测定淋巴结中CD4~+T、CD8~+T及CD4~+IFN-γ和CD8~+IFN-γ细胞比例。结果与对照组比较,STM模型组TNF-α、IL-1β、IL-6及TLR4、MyD88、NF-κB mRNA水平升高(P0.01),参苓白术散组和庆大霉素组较比STM模型组呈下降趋势(P0.05);STM模型组TLR4、MyD88、NF-κB蛋白含量高于对照组(P0.01),参苓白术散组和庆大霉素组低于STM模型组(P0.05);STM模型组CD4~+T、CD8~+T及CD4~+IFN-γ和CD8~+IFN-γ细胞比例均高于对照组(P0.05),参苓白术散组高于STM模型组(P0.05),庆大霉素组较STM模型组有下降趋势(P0.05)。结论参苓白术散对STM感染具有一定治疗效果,治疗机制可能与下调TLR4-MyD88-NF-κB信号诱导的炎性细胞因子分泌及上调CD4~+T、CD8~+T比例及功能有关。     

脑梗死合并肺部感染患者TNF-α、HMGBl、TLR4-NF-κB信号通路改变研究

目的探究脑梗死合并肺部感染患者的肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)和高迁移率族蛋白Bl(High mobility group protein Bl,HMGBl)水平及其临床价值研究。方法2018年1月-2019年2月儋州市人民医院收治的急性脑梗死患者作为研究对象,其中急性脑梗死合并肺部感染患者30例作为感染组,急性脑梗死无肺部感染患者80例作为非感染组,选择同期于此医院体检的健康者30名作为对照组。采用酶联免疫吸附法(Enzyme-linked immuno sorbent assay,ELISA)检测血清HMGB1和细胞因子IL-6、TNF-α水平,采用Western Blot法检测血清Toll样家族受体-4(Toll like receptor-4,TLR4)、核因子κB(nuclear factor kappa-B,NF-κB)、髓样分化因子(myeloiddifferentiationfactor88,MyD88)表达水平。结果感染组的血清HMGB1、TLR4、NF-κB、MyD88表达及细胞因子IL-6、TNF-α水平均高于非感染组和对照组(P<0.05);感染组患者大梗死灶、中等梗死灶、小梗死灶各指标总体水平差异具有统计学意义(P<0.05)。大梗死灶、中等梗死灶两亚组患者的血清HMGB1、TLR4、NF-κB、MyD88表达及细胞因子IL-6、TNF-α水平均高于小梗死灶亚组(P<0.05);急性脑梗死合并肺部感染患者的血清HMGB1和TNF-α水平呈正相关(r=0.523,P<0.001)。结论脑梗死合并肺部感染患者伴随TNF-α、HMGBl、TLR4-NF-κB信号通路的明显改变,且与梗死灶大小具有相关性,其机制有待进一步研究。     

基于TLRs-NF-κB信号通路探讨抗生素药物联合康妇炎胶囊治疗慢性子宫内膜炎疗效及机制

目的：基于Toll样受体-核因子κB(TLRs-NF-κB)信号通路探讨抗生素药物联合康妇炎胶囊治疗慢性子宫内膜炎(CE)的疗效及机制。方法：选择2021年1月-2022年1月本院92例CE患者，按1:1比例随机分为两组，两组均常规给予抗生素药物治疗，观察组联合康妇炎胶囊治疗。对比两组临床疗效，治疗前后外周血单个核细胞(PBMCs)中TLR2、TLR4、NF-κB mRNA表达及血清TLRs-NF-κB相关炎症因子[肿瘤坏死因子-α(TNF-α)、干扰素γ(IFN-γ)、白介素-1β(IL-1β)、IL-6、IL-8]水平。结果：治疗1周、2周后两组中医证候评分均下降，且观察组(6.45±1.14分、4.33±0.81分)低于对照组(7.59±1.22分、5.16±1.23分)(P<0.05);两组PBMCs中TLR2、TLR4、NF-κB mRNA及血清TNF-α、IFN-γ、IL-1β、IL-6、IL-8均降低，且观察组低于对照组(P<0.05)。观察组愈显率(78.3%)高于对照组(58.7%),随访6个月观察组复发率(2.8%)低于对照组(14.8%)(P<0...     

Toll样受体7激动剂对荷瘤小鼠肾癌的抑制作用及免疫机制

目的　研究Toll样受体7激动剂Imiquimod对荷瘤小鼠肾癌的抑制作用及免疫机制。方法　用Renca肾癌细胞构建BABL/c小鼠肾癌模型,实验分为control组、imiquimod组和sorafenib组。观察3组小鼠肿瘤体积及重量、抑瘤率,qPCR法检测肿瘤组织中炎性相关因子肿瘤坏死因子α（Tumor necrosis factor-α,TNF-α）、白细胞介素1β（Interleukin-1β,IL-1β）、白细胞介素6（Interleukin-6,IL-6）、干扰素α（Interferon-α,IFN-α）、干扰素β（Interferon-β,IFN-β）、干扰素γ（Interferon-γ,IFN-γ）及Toll样受体通路相关因子Toll样受体7（Toll-like receptor 7,TLR7）、髓样分化因子88（Myeloid differentiation primary response gene 88,MyD88）、核因子κB （Nuclear factor κB,NF-κB）mRNA表达,Western blot法检测瘤组织中TLR7、MyD88、NF-κB蛋白表达。流式细胞术检测脾脏中CD4+T、CD8+T、CD4+IFN-γ和CD8+IFN-γ细胞比例。结果　与control组比较,imiquimod组和sorafenib组小鼠的肿瘤体积及瘤体重量降低（P＜0.05）;与control组相比,imiquimod组TNF-α、IL-6、IL-1β、IFN-α、IFN-β、IFN-γ及TLR7、MyD88、NF-κB mRNA水平升高（P＜0.05）,而sorafenib组各因子略有上升（P＞0.05）;与control组和sorafenib组比较,imiquimod组CD4+T、CD8+T细胞比例有不同程度的升高（P＞0.05）,CD4+IFN-γ和CD8+IFN-γ细胞比例增加（P＜0.05）。结论　Toll样受体7激动剂通过活化TLR7-MyD88-NF-κB信号刺激多种炎性细胞因子分泌,并上调CD4+T、CD8+T比例及功能,对荷瘤小鼠肾癌发挥抑制作用。     

重型颅脑损伤患者术后颅内感染病原菌及脑脊液单核细胞TLR4 mRNA与MyD88 mRNA水平

目的 分析重型颅脑损伤(STBI)患者术后颅内感染病原菌及脑脊液单核细胞中Toll样受体4(TLR4)mRNA和髓系分化因子88(MyD88)mRNA。方法 选择2019年3月-2021年9月青岛市中医医院收治的STBI患者121例，术后颅内感染患者为感染组47例，未发生颅内感染患者为无感染组74例，分析感染组患者病原菌特点。依据神经功能缺损评分(NIHSS)将感染组患者分为轻度组8例、中度组20例、重度组19例，比较不同分组患者脑脊液单核细胞TLR4和MyD88表达，及感染相关指标肿瘤坏死因子-α(TNF-α)、干扰素-γ(IFN-γ)、免疫球蛋白G(IgG)水平。结果 STBI患者术后颅内感染共培养分离病原菌47株，其中革兰阳性菌28株占59.57%,以凝固酶阴性葡萄球菌和金黄色葡萄球菌为主；革兰阴性菌19株占40.43%,以鲍氏不动杆菌和铜绿假单胞菌为主；感染组NIHSS评分、脑脊液单核细胞TLR4 mRNA和MyD88 mRNA表达量、血清TNF-α、IFN-γ均高于无感染组，血清IgG低于无感染组(P<0.05);重度组患者脑脊液单核细胞TLR4 mRNA和MyD88 ...     

脂多糖经MyD88/NF-κB信号途径抑制Bewo细胞中乙型肝炎病毒复制

目的 探讨Toll样受体4(TLR4)配体脂多糖(LPS)抑制人滋养层细胞Bewo中乙型肝炎病毒( HBV)复制的作用机制,为防治HBV宫内感染提供依据.方法 首先将2μg 1.3倍HBV全基因重组质粒pcDNA3.1(+)-HBV1.3转染Bewo细胞12h后,以TLR4配体LPS处理3d.尔后用LPS处理Bewo细胞,观察IFN-β、TNF-α表达的动力学、NF-κB拮抗剂二硫代氨基甲酸吡咯烷( PDTC)对LPS诱导Bewo细胞产生细胞因子的作用.采用微粒子酶免疫分析法(MEIA)和荧光定量PCR法分别检测HBsAg、HBeAg和HBV DNA水平,并以ELISA和RT-PCR分别检测IFN-β、TNF-α水平及TIR结构域的转接蛋白(TRIF)、髓样分化蛋白(MyD88)表达.结果 与对照组比较,LPS可显著抑制Bewo细胞中HBV复制(P＜0.01),且LPS可显著诱导Bewo细胞产生TNF-α(P＜0.05),呈时间和剂量依赖性.PDTC可抑制LPS诱导细胞产生TNF-α,显著低于对照组(P＜0.01),但对IFN-β无显著作用(P＞0.05).与对照组比较,LPS可诱导HBV重组质粒转染的Bewo细胞表达MyD88(P＜0.01).结论 通过MyD88/NF-κB信号途径诱导Bewo细胞产生TNF-α,TLR4配体LPS可显著抑制HBV复制.     

不同剂量流感病毒感染小鼠模型免疫应答的比较性研究

目的 比较不同剂量流感病毒感染小鼠后肺组织急性损伤情况,初步探讨感染剂量与机体抗病毒的固有、适应性免疫应答的关系。方法 用流感病毒A/PR/8/34（PR8;H1N1）构建小鼠感染102 PFU和103 PFU剂量模型,HE法检测肺组织损伤情况,HA法和免疫荧光染色法检测肺组织病毒滴度和感染程度,RT - PCR法检测肺组织炎性因子干扰素α（interferon - α, IFN - α）、干扰素β（interferon - α, IFN - β）、白细胞介素1β（interleukin - 1β, IL - 1β）、白细胞介素6（interleukin - 6, IL - 6）、肿瘤坏死因子α（tumor necrosis factor - α, TNF - α）及Toll样受体7（Toll - like receptor - 7, TLR7）、髓样分化因子88（myeloid differentiation primary response gene 88, MyD88）、肿瘤坏死因子受体相关蛋白6（TNF receptor associated factor 6, TRAF6）和核因子κB（nuclear factor κB, NF - κB）mRNA水平,免疫组化法对肺组织TLR7、MyD88、TRAF6和NF - κB蛋白定位。流式细胞术检测肺组织、支气管肺泡灌洗液（bronchoalveolar lavage fluid, BALF）和淋巴结中CD4+、CD8+T细胞比例。结果 与102 PFU组比较,103 PFU组小鼠肺组织病毒滴度显著升高（t = 3.071,P = 0.008）,炎症因子IFN - α、IFN - β、IL - 1β、IL - 6、TNF - α mRNA水平上升（t = 4.816,P = 0.003;t = 4.104,P = 0.006;t = 3.992,P = 0.007;t = 4.049,P = 0.007;t = 3.737,P = 0.009）,TLR7、MyD88、TRAF6和NF - κB mRNA水平有不同程度的升高（t = 2.905,P = 0.027;t = 3.854,P = 0.008;t = 3.760,P = 0.009;t = 4.312,P = 0.005）及蛋白表达显著增加（t = 4.712,P = 0.003;t = 4.008,P = 0.007;t = 4.398,P = 0.005;t = 4.564,P = 0.004）,BALF、肺组织和淋巴结中CD4+T细胞比例呈上升趋势（t = 3.771,P = 0.009;t = 2.463,P = 0.049;t = 3.386,P = 0.015）,BALF和肺组织CD8+T细胞比例上调（t = 5.297,P = 0.002;t = 3.502,P = 0.013）。结论 病毒载量影响机体固有和适应性免疫应答状态,通过上调 TLR7 - MyD88 - TRAF6 - NF - κB信号通路促进下游炎症反应,并启动CD4+T和CD8+T细胞发挥抗病毒效应。     

脂多糖经MyD88／NF-KB信号途径抑制Bewo细胞中乙型肝炎病毒复制

目的探讨Toll样受体4（TLR4）配体脂多糖（LPS）抑制人滋养层细胞Bewo中乙型肝炎病毒（rtBv）复制的作用机制,为防治HBV宫内感染提供依据。方法首先将2txg1．3倍HBV全基因重组质粒pcDNA3．1（＋）-HBV1．3转染Bewo细胞12h后,以TLR4配体LPS处理3d。尔后用LPS处理Bewo细胞,观察IFN—β、TNF-a表达的动力学、NF—KB拮抗剂二硫代氨基甲酸吡咯烷（PDTC）对LPS诱导Bewo细胞产生细胞因子的作用。采用微粒子酶免疫分析法（MEIA）和荧光定量PCR法分别检测HBsAg、HBeAg和HBVDNA水平,并以ELISA和RT—PCR分别检测IFN-β、TNF—a水平及TIR结构域的转接蛋白（TRIF）、髓样分化蛋白（MyD88）表达。结果与对照组比较,LPS可显著抑制Bewo细胞中HBV复制（P〈0．01）,且LPS可显著诱导Bewo细胞产生TNF-a（P〈0．05）,呈时间和剂量依赖性。PDTC可抑制LPS诱导细胞产生TNF-a,显著低于对照组（P〈0．01）,但对IFN—β无显著作用（P〉0．05）。与对照组比较,LPS可诱导HBV重组质粒转染的Bewo细胞表达MyD88（P〈0．01）。结论通过MyD88／NF—KB信号途径诱导Bewo细胞产生TNF—a,TLR4配体LPS可显著抑制HBV复制。     

HMGB1 - TLR9 - MyD88 - TRAF6 - NF - κB信号通路在急性胰腺炎肠粘膜屏障损伤中的作用

目的 探讨雨蛙素和脂多糖诱导的小鼠重症急性胰腺炎（severe acute pancreatitis, SAP）模型中肠道粘膜屏障损伤的机制。方法 采用雨蛙素和脂多糖诱导小鼠SAP模型。将雄性C57BL/6J小鼠随机分为对照组和SAP组,每组12只。每组分为6 h和12 h两个时间点。HE染色观察胰腺及回肠病理学,ELISA法检测TNF - α、IL - 1β、IL - 6、DAO和EndoCAb的表达水平,Western blot检测HMGB1、TLR9、MyD88、TRAF6、NF - κB p65、p - NF - κB p65和occludin表达水平,TUNEL法检测肠上皮细胞凋亡情况。采用单因素方差分析比较不同处理组之间的结果,组间差异进一步采用LSD - t多重比较。结果 与对照组相比,SAP组血清中 IL - 1β、IL - 6、TNF - α、DAO 和EndoCAb水平升高（F = 104.50,P＜0.05;F = 140.36,P＜0.05;F = 328.21,P＜0.05;F = 372.23,P＜0.05;F = 80.67,P＜0.05）;HMGB1、TLR9、MyD88、TRAF6和p - NF - κB p65蛋白表达升高（F = 65.95,P＜0.05;F = 84.16,P＜0.05;F = 58.27,P＜0.05;F = 122.26,P＜0.05;F = 178.38,P＜0.05）,occludin的表达降低（F = 456.91,P＜0.05）、小鼠肠上皮细胞凋亡增加(F = 400.47,P＜0.05)。与12 h SAP组相比,6 h SAP组血清IL - 1β、IL - 6和TNF - α水平及p - NF - κB p65蛋白表达升高更明显(ｔ = 4.95,P＜0.05;ｔ = 4.57,P＜0.05;ｔ = 3.32,P＜0.05;ｔ =2.93,P＜0.05)。与6 h SAP组相比,12 h SAP组回肠组织中occludin水平降低更明显（ｔ = - 3.52,P＜0.05）,血清DAO、EndoCAb水平、HMGB1、TLR9、MyD88、TRAF6蛋白表达水平更高（ｔ=6.55,P＜0.05;ｔ = 4.96,P＜0.05;ｔ = 6.88,P＜0.05;ｔ = 8.52,P＜0.05;ｔ = 7.37,P＜0.05;ｔ = 7.78,P＜0.05）,肠上皮细胞出现细胞凋亡更明显 (ｔ = 3.10,P＜0.05)。结论 HMGB1 - TLR9 - MyD88 - TRAF6 - NF - κB信号通路可能参与了SAP肠粘膜屏障损伤。     

Acute ethanol administration inhibits Toll-like receptor 4 signaling pathway in rat intestinal epithelia

Excess alcohol intake, as in binge drinking, increases susceptibility to microbial pathogens. Alcohol impairs macrophage function by suppression of the Toll-like receptor 4 (TLR4) pathway. This study investigated the effects of acute ethanol intake on the TLR4 pathway in rat intestinal epithelia, which usually encounters luminal antigens at first and participates in the development of intestinal immunity. Twenty Wistar rats were randomly assigned to an ethanol group given ethanol as a 25% (v/v) solution in water at 7.5 g/kg, or a control group given saline, by oral gavage daily for 3 days. The epithelial histology and ultrastructure, the intestinal microflora, peripheral and portal venous plasma lipopolysaccharide (LPS) levels, and somatostatin (SST) levels in the peripheral plasma and small intestine were evaluated. Somatostatin receptor 2 (SSTR2), TLR4, TANK binding kinase-1 (TBK1), activated nuclear factor-κB (NF-κB), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in the intestinal mucosa were assayed. LPS responsiveness with or without SST pretreatment was assayed in vitro by quantification of TLR4, TBK1, activated NF-κB, IFN-γ and TNF-α in isolated intestinal epithelia. Mucosal damage was observed in the ethanol group by light and electron microscopy. Escherichia coli cultures were unchanged in rat intestine of the ethanol group compared with controls, but lactobacilli cultures were reduced (p < 0.05). LPS levels increased in peripheral and portal venous plasma (p < 0.05), but mucosal TLR4, TBK1, nuclear NF-κB, IFN-γ and TNF-α were unchanged in the ethanol group. LPS treatment in vitro up-regulated the level of TLR4, TBK1 and nuclear NF-κB as well as the production of IFN-γ and TNF-α in isolated intestinal epithelia in the control (p < 0.05), but not the ethanol group. The stimulatory effects of LPS on intestinal epithelia isolated from the control group were significantly inhibited by SST pretreatment (p < 0.05). The peripheral plasma and intestinal levels of SST and the mucosal expression of SSTR2 in the ethanol group were significantly higher than in the control group (p < 0.05). These findings suggest the hyposensitivity of intestinal epithelial TLR4 to LPS induced by acute alcohol abuse probably through ethanol per se and ethanol-enhanced intestinal mucosal SST pathway may be a novel mechanism for increased susceptibility to intestinal pathogens.     

Decreased somatostatin is related to the hypersensitivity of intestinal epithelia to LPS via upregulated TLR4-TBK1 pathway in rats chronically exposed to ethanol

Chronic alcoholics are predisposed to the development of a systemic inflammatory response syndrome, which is usually triggered in the gut. This study aimed to investigate in rats the role of intestinal epithelial inflammatory responsiveness in the susceptibility of alcoholics to excessive inflammation. Thirty Wistar rats were randomly divided into three groups: 10 rats killed immediately after acclimation (baseline control), 10 rats treated with 25% (vol/vol) ethanol for 6 months (ethanol group), and 10 rats given double-distilled water until killed simultaneously with the ethanol group (9-month control). The intestinal microflora, the epithelial histology and ultrastructure, the level of Toll-like receptor 4 (TLR4), TANK-binding kinase-1 (TBK1), and activated nuclear factor-κB (NF-κB) in the intestinal mucosa, and somatostatin (SST) levels in plasma and small intestine were evaluated in each group. Isolated intestinal epithelia from each rat were used to examine lipopolysaccharide (LPS) responsiveness with or without SST pretreatment by quantification of TLR4, TBK1, activated NF-κB, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α). Compared with both the control groups, the amount of mucosal Escherichia coli in the ethanol group was not changed, whereas the number of intestinal lactobacilli in the ethanol group was significantly reduced (P < .05). Mild inflammatory injury and upregulation of TLR4 and TBK1 were observed in the intestinal mucosa of the ethanol group. The LPS-enhanced in vitro expression of TLR4, TBK1, and production of IFN-γ and TNF-α in isolated intestinal epithelia of the ethanol group were significantly higher than those in either control group (P < .05) and were dramatically inhibited by SST (P < .05), whereas NF-κB was activated by LPS only in the control groups. The plasma and intestinal levels of SST in the ethanol group were significantly lower than those in either control group (P < .05). These findings suggest that impairment of intestinal SST production by chronic ethanol administration leading to upregulation of the TLR4-TBK1 pathway may be one of the mechanisms underlying the LPS hypersensitivity of intestinal epithelia.     

Mycobacterium indicus pranii mediates macrophage activation through TLR2 and NOD2 in a MyD88 dependent manner

Mycobacterium indicus pranii (MIP) is a non-pathogenic strain of mycobacterium and has been used as a vaccine against tuberculosis and leprosy. Here, we investigated the role of different pattern recognition receptors in the recognition of heat-killed MIP by macrophages. Treatment of macrophages with MIP caused upregulation of pro-inflammatory cytokines (like TNFα and IL-1β) which was mediated through both TLR2 and NOD2, as revealed by our knockdown and/or knockout studies. Mechanistically, MIP-induced macrophage activation was shown to result in NF-κB activation and drastically abrogated by MyD88 deficiency, suggesting its regulation via an MyD88-dependent, NF-κB pathway. Interestingly, the IFN-inducible cytokine, CXCL10, which is known target of the TRIF-dependent TLR pathway was found to be upregulated in response to MIP but, in an MyD88-dependent manner. Collectively, these results demonstrate macrophages to recognize and respond to MIP through a TLR2, NOD2 and an MyD88-dependent pathway. However, further studies should clarify whether additional TLR-dependent or -independent pathways also exist in regulating the full spectrum of MIP action on macrophage activation.     

CTRP9抑制幼年哮喘小鼠气道平滑肌细胞增殖和炎性反应的研究

目的 研究C1q/肿瘤坏死因子相关蛋白9(CTRP9)对哮喘幼鼠气道平滑肌细胞(airway smooth muscle cells,ASMCs)增殖和气道炎症的作用。方法 ELISA检测正常、哮喘儿童和小鼠血清中CTRP9含量;原代培养哮喘小鼠ASMCs,经pcDNA3.1-CTRP9转染后,MTT检测ASMCs增殖,ELISA测定TNF-α和IL-6含量,Western 印记检测TLR4和NF-κB p65蛋白表达以及NF-κB p65磷酸化水平;pcDNA3.1-CTRP9转染哮喘小鼠,HE染色观察肺组织炎性细胞的浸润程度;收集小鼠支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF),光镜下检测嗜酸性粒细胞、巨噬细胞和中性粒细胞数目;检测小鼠肺部TNF-α、IL-6、TLR4和NF-κB的表达。结果 哮喘儿童和小鼠血清中CTRP9含量低于正常组;CTRP9能抑制ASMCs增殖、炎症因子分泌和TLR4/NF-κB通路活化;CTRP9也能抑制哮喘小鼠肺部炎性细胞浸润、各炎性反应细胞数目、炎症因子分泌和TLR4/NF-κB通路活化。结论 CTRP9能抑制幼年哮喘小鼠ASMCs增殖和炎性反应。