EFFECT OF INTERLEUKIN-1β ON GROWTH HORMONE GENE EXPRESSION AND ITS POSSIBLE MOLECULAR MECHANISM IN RAT MtT/S SOMATOTROPH CELLS

Objective To elucidate the effect of interleukin-1β （IL- 1β） on human growth hormone （hGH） gene expression in a rat somatotropic pituitary cell line MtT/S.
Methods Stably transfected MtT/S cells were firstly established by transfecting 484-Lucl plasmid which contained hGH gene promoter --484 to ＋30 bp and luciferase reporter gene. The effect of IL-1β on hGH gene expression was determined by assaying the luciferase activities. RT-PCR method was also used to determine whether IL-1 recepor mRNA was expressed in MtT/S cells.
Results The 10^3 U/mL IL-1β stimulated secretion and synthesis of GH, and promoted the 5＇-promoter activity of GH gene in stably transfected MtT/SGL cells with the action of 1.38 times above the control. Among inhibitors of signaling transduction pathways, mitogen-activated protein kinase kinase （MAPKK/MEK） inhibitor PD98059 （40 μmol/L） and p38 mitogen-activated protein kinase （MAPK） inhibitor SB203580 （5 μmol/L） completely blocked the stimulatory effect of IL-1μ, and phosphatidylinositol-3-kinase （PI3-K） inhibitor LY294002 partly abolished the effect of IL-1μ. Western blot analysis further confirmed the activation of phosphorylated MEK and p38 MAPK in MtT/SGL cells. Neither over-expression of Pit- 1 nor inhibition of Pit- 1 expression affected induction of hGH promoter activity by IL-1μ. A series of deletion constructs of hGH promoter were created to identify the DNA sequence that mediated the effect of IL-1β, and results showed that the stimulatory effect of IL-1β was abolished following deletion of the --196 to -- 132 bp fragment.
Conclusions IL-1β promotes GH secretion and synthesis in rat MtT/S somatotroph cells. The stimulatory effect of IL-1β on hGH gene promoter appears to require the activation of MEK, p38 MAPK, PI3-K, and a fragment of promoter sequence that spans the -196 to -132 bp of the gene, but it may be unlinked with Pit-1 protein.     

白细胞介素1β促进GH3细胞中人生长激素基因表达的机制

目的研究白细胞介素1β(IL-1β)对大鼠垂体GH3细胞中人生长激素(hGH)基因启动子活性的影响及其可能的调节机制.方法采用荧光素酶报告基因方法.建立含hGH基因启动子(-484～30 bp)和荧光素酶融合基因的稳定转染GH3细胞株,然后加入IL-1β或IL-1β与胞内信号转导途径的抑制剂,通过检测细胞培养液和细胞裂解液中GH的含量以及GH3细胞内荧光素酶的变化,反映IL-1β对GH分泌、合成、hGH基因启动子活性的影响及可能的作用机制.结果IL-1β(10～104U/ml)均能刺激大鼠垂体GH3细胞中GH的分泌和合成,102～104 U/ml的IL-1β还能剂量依赖性地增加细胞中荧光素酶的表达,最高达对照组的161%;在胞内信号转导抑制剂中,丝裂原活化蛋白激酶(MAPK)特异性抑制剂PD98059(40μmol/L)和p38MAPK抑制剂SB203580(5 μmol/L)均能完全阻断IL-1β促进GH3细胞中荧光素酶表达的作用,磷脂酰肌醇3激酶(PI3-K)抑制剂LY294002(10 μmol/L)能部分抑制IL-1β的促进作用;Pit-1蛋白过表达和表达被抑制对IL-1β的促进作用没有影响;在含不同长度hGH基因启动子序列的质粒中,IL-1β促进GH3细胞中hGH基因启动子活性的关键序列在-196～-132 bp之间.结论IL-1β能增强垂体GH3细胞中hGH基因的启动子的活性,此作用可能需要激活细胞内依赖MAPK、p38MAPK和PI3-K等激酶的信号转导途径完成,并与hGH基因上游-196～-132 bp启动子序列密切相关,但与Pit-1蛋白无关.     

C反应蛋白对NRK-52E细胞NF-κB信号传导与IL-6mRNA表达的影响

目的:探讨C反应蛋白(CRP)对肾小管上皮细胞NF-κB信号与IL-6 mRNA表达的影响。方法:体外培养的骨小管上皮细胞NRK-52E,分3组:①对照组:设阴性对照(加入PBS)和阳性对照(AngⅡ,1μmol/L);②CRP刺激组(分别加入CRP 5,10,20 mg/L);③干预组:加入10 mg/L CRP,同时加入CRP抗体1μmol/L或SB203580(10μmol/L,p38MAPK的特异性抑制剂)。分别应用ELISA、RT-PCR、Western Blot技术和EMSA方法,检测细胞p38MAPK的磷酸化、NF-κB活性与IL-6分泌与mRNA表达的变化。结果:CRP呈剂量依赖性上调NRK-52E细胞IL-6分泌与mRNA的表达。CRP上调NRK-52E细胞p38MAPK的磷酸化与NF-κB与DNA的结合活性。CRP抗体、SB203580下调CRP对NRK-52E细胞的炎性激活效应。结论:CRP直接诱导NRK-52E细胞NF-κB活化及下游因子IL-6 mRNA与蛋白质的高表达,可能通过p38MAPK的磷酸化途径。     

丝裂原活化蛋白激酶通路对脂多糖诱导RAW264.7细胞肿瘤坏死因子α基因表达的协同调节作用

目的 探讨脂多糖（LPS）诱导RAW264.7细胞肿瘤坏死因子α(TNF-α)基因表达过程中丝裂原活化蛋白激酶（MAPK）通路的协同调节作用及其分子机制。方法 用蛋白激酶活性测定分析LPS刺激RAW264．7细胞引起的激酶活性变化;用报告基因技术和反转录聚合酶链反应（RT－PCR）方法研究LPS诱导的TNF－α基因转录的分子机制。结果 LPS刺激RAW264．7细胞可引起细胞外信号调节激酶1（ERK1）、c-Jun氨基末端激酶1（JNK1）和p38MAPK的一过性激活,用MAPK上游激酶的活性突变体分别转染RAW264．7均可不同程度地诱导TNF－α启动子转录活性;而且,这些MAPK通路激活诱导的TNF－α启动子转录活性表现出明显的协同效应;三种MPAPK的无活性突变体均显示出对LPS刺激引起的TNF－α启动子转录激活的抑制效应;RT－PCR的结果证实,ERK、JNK和p38MAPK的特异性抑制剂对TNF－αmRNA表达具有不同程度的抑制作用。结论 LPS刺激引起的TNF－α启动子转录活性增加,可能涉及了ERK、p38和JNK三条通路的激活;这些通路通过协同效应共同发挥对TNF－α基因表达的调控。     

ESM-1在转染MEK基因的ECV304细胞中的表达

目的探讨内皮细胞特异性分子-1（ESM-1）在转染MEK基因的人脐静脉内皮细胞中的表达,探讨ESM-1的表达是否受分裂原激活的蛋白激酶（MAPK）信号转导通路的调节。方法脂质体转染高活性的MEK基因人ECV304细胞,Western blot检测ESM-1在ECV304细胞中的表达。结果成功获得稳定转染高活性MEK基因的细胞株,并检测到胞外信号调节的激酶（ERKs）的表达量在二株细胞中没有变化,而pERK-2和ESM-1在转染MEK基因的细胞中表达高于未转染的细胞。结论ESM-1可能处于ERK-2的下游,其表达可能受MAPK信号转导通路的调节。     

白介素1-β对人肺腺癌细胞COX-2表达的作用及调节机制

目的 探讨细胞因子白介素-1β（IL-1β）对人肺腺癌细胞株A549细胞环氧合酶2（COX-2）表达的影响及调节机制。方法 A549细胞培养达80％融合后，用不同浓度的IL-1β（0、0.1、1、5和10ng／mL）干预或用5ng/mL IL-1β干预不同时间（0、3、6、9、12和24h）观察白介素-1β（IL-1β）对A549细胞COX-2表达的影响；用5ng／mL IL-1β与有丝分裂原激活的细胞外调节激酶（ERK）抑制剂PD098059、P38有丝分裂原激活的蛋白激酶（MAPK）抑制剂SB203580、蛋白激酶C（PKC）抑制剂H-7共同干预A549细胞观察IL-1β诱导A549细胞COX-2表达的信号传导途径；用COX-2系列报告基因质粒及对照质粒转染A549细胞后予以IL-1β干预，以不加IL-1β干预的细胞为对照组观察IL-1β对COX-2启动子的影响；westem blot检测COX-2蛋白表达，RT—PCR检测COX-2 mRNA表达。COX-2报告基因活性应用荧光素酶活性分析法测定。结果 A549细胞COX-2蛋白表达和mRNA表达呈IL-1β浓度依赖性表达增加，干预9h表达达高峰；SB203580、H-7可明显抑制IL-1β诱导A549细胞COX-2表达，PD098059对IL-1β诱导A549细胞COX-2表达无影响；IL-1β对COX-2报告基因无影响。结论 PKC途径和P38 MAPK途径参与IL-1β诱导A549细胞COX-2蛋白表达。     

p38 MAPK对冲击波促进T淋巴细胞增殖和分泌IL-2的作用

目的：研究有丝分裂原激活蛋白激酶p38（p38 MAPK）对冲击波促进激活的T淋巴细胞增殖及分泌IL-2的作用。方法：预先用p38 MAPK抑制剂( SB203580,20 μmol•L^-1)分别与人外周血单个核细胞（PBMC）和Jurkat T细胞共同培养,同时设立不含SB203580的阴性对照组,再用冲击波和PHA或抗-CD3/抗-CD28抗体的亚刺激量作用,检测T淋巴细胞增殖和分泌IL-2的变化。采用免疫印迹法,用抗- p38MAPK抗体及抗-磷酸化的p38MAPK(Thr180/Tyr182)抗体,测定冲击波作用后Jurkat T细胞上的p38 MAPK的表达及磷酸化。结果：与未用冲击波作用组比较,被PHA激活的PBMC细胞,在能量密度为(0.180±0.015) mJ•mm^-2的冲击波作用100、150、200、250、300、330和360次时,细胞对³H-TdR掺入量明显增高（P<0.01）。加入SB203580的PHA激活的PBMC细胞,在上述同样强度的冲击波作用时,细胞对³H-TdR掺入量低于没有加入SB203580对照组（P<0.01）。与未受冲击波作用组比较,被CD3和CD28激活的Jurkat T细胞,在上述同样强度的冲击波作用时,细胞上清液中的IL-2活性明显增高（P<0.01）。加入SB203580的CD3和CD28激活的Jurkat T细胞,在该强度的冲击波作用时,细胞上清液中的IL-2水平低于比未加入SB203580的对照组（P<0.01）。50～250次的(0.180±0.015)mJ•mm²的低能冲击波可使Jurkat T细胞的p38MAPK磷酸化, p38MAPK的磷酸化程度随着冲击波作用次数的增加而增加。结论：SB203580可抑制低能冲击波对激活的T淋巴细胞的增殖及分泌IL-2作用;低能冲击波通过激活T淋巴细胞内的p38 MAPK,促进激活的T淋巴细胞增殖及分泌IL-2。     

MRP8/MRP14诱导腹腔巨噬细胞释放炎性细胞因子

目的 探讨MRP8/MRP14诱导小鼠腹腔巨噬细胞细胞因子表达效应及其作用机制.方法 Luminex xMAP液相芯片系统检测重组MRP8/MRP 14蛋白诱导腹腔巨噬细胞6种细胞因子/趋化因子的水平变化;MRP14不同结构域融合蛋白刺激细胞,检测TNF-α、IP-10和IL-6表达;Western blot检测MRP8/MRP14刺激细胞p38MAPK、JNK和ERK激酶磷酸化变化;细胞预先用p38MAPKs、JNK、ERK激酶抑制剂、TLR4和RAGE受体拮抗剂预处理,之后给予MRP8/MRP14蛋白刺激,检测TNF-α、IP-10和IL-6表达.结果 MRP8/MRP14能显著诱导TNF-α、IP-10和IL-6的表达,与对照组相比,蛋白表达水平分别升高约98.2、378.6和6.3倍(P＜0.01),MRP8/MRP14不能诱导IL-2、IL-5和IFN-g的表达;MRP14全长及其结构域EFhand-1、EFhand-2及EFhand-1+2融合蛋白能够诱导TNF-α、IP-10和IL-6的表达(P＜0.01),CT末端结构域不具有诱导活性;MRP8/MRP 14刺激细胞后1 h p38 MAPK、JNK及ERK激酶发生显著磷酸化变化,持续至2h;与单纯MRP8/MRP 14组相比,p38MAPK抑制剂SB203580显著抑制TNF-α、IP-10和IL-6的表达(P＜0.05);JNK抑制剂SP600125显著抑制TNF-α和IP-10的表达(P＜0.05),对IL-6的表达无影响;ERK及其上游MEK1/2的抑制剂PD98059和U0126显著抑制IL-6的表达(P＜0.05);TLR4抑制剂TAK242抑制了MRP8/MRP14诱导的TNF-α、IP-10和IL-6的表达(P＜0.05),而RAGE中和性抗体仅部分抑制MRP8/MRP14诱导的IL-6的表达(P＜0.05).结论 MRP8/MRP14能够诱导小鼠腹腔巨噬细胞TNF-α、IP-10和IL-6的表达;MRP蛋白以包含有钙离子结合基序的结构域具有诱导细胞因子表达的活性;TNF-α和IP-10的表达与TLR4受体及其下游的p38MAPKs、JNK通路有关,IL-6的表达则同时由TLR4和RAGE受体介导,继而激活下游的p38MAPKs和ERK信号通路.     

Chrysanthemum indicum linnéextracts attenuate the mitogenic effect of epinephrine on human HCC cells

Objective: To investigate the stimulatory effect of epinephrine(Epi) and the antagonistic effect of Chrysanthemum indicum Linné extracts (CILE) on Epi-induced growth of human hepatocellular carcinoma(HCC) cells. Methods: The stimulatory effect of Epi and inhibitory effect of CILE on the growth of HepG2 and MHCC97H cells were investigated using a proliferation assay in correlation with βadrenergic receptor(β 2-AR) blockade, a MEK1/MEK2 inhibitor, and assessment of MAPK/ERK1/2 intracellular activity. Results:...     

地塞米松对哮喘患者外周血单个核细胞p38MAPK表达的影响

目的探讨支气管哮喘患者外周血单个核细胞(PBMCs)p38MAPK表达的变化及地塞米松(DEX)对其的影响。方法分离培养哮喘患者和正常健康者的PBMCs。分别采用蛋白质印迹和ELISA方法检测PBMCs核蛋白p38MAPK的表达及细胞上清液中IL -4、IL- 5的蛋白质浓度。结果哮喘对照组PBMCs核蛋白p38MAPK表达及细胞上清液中IL -4、IL- 5的蛋白质浓度较正常对照组显著升高(P<0. 001),DEX处理组核蛋白p38MAPK表达及细胞上清液中IL- 4、IL- 5的蛋白质浓度较哮喘对照组显著降低(P<0. 01)。通过直线相关分析发现,PB MCs核蛋白p38MAPK表达与培养上清液中IL- 4、IL- 5蛋白质含量之间均呈显著正相关(r分别=0. 71、0. 64,P均<0. 01)。结论p38MAPK可能参与支气管哮喘的病理生理过程。DEX可能通过作用于p38MAPK这一靶点发挥其抗炎效应。     

NALP3炎性复合体及p38 MAPK信号通路在氧化应激中的作用及阿魏酸钠的干预机制

目的探讨氧化应激时成纤维细胞（NIH-3T3）中NALP3炎性复合体、p38丝裂原活化蛋白激酶（MAPK）的变化及阿魏酸钠的干预机制。方法将NIH-3T3细胞分为6组:对照组;H2O2 （200 μmol/L）刺激组;阿魏酸钠（400 μg/mL）组;H2O2 +N-乙酰半胱氨酸（H2O2 200 μmol/L+ NAC 5 mmol/L）组（抗氧化组）;H2O2 + p38 MAPK抑制剂（H2O2 200 μmol/L+ SB203580 5 μmol/L）组（p38 MAPK阻断剂组）;阿魏酸钠干预(H2O2 200 μmol/L+阿魏酸钠 400 μg/mL)组。培养24 h后,荧光定量PCR检测各组NIH-3T3细胞中NALP3、Caspase-1及P38α mRNA的表达;培养48 h后,Western blot检测各组NIH-3T3细胞中NALP3、p-p38和p38蛋白的表达量（p-p38为p38活化表示形式,p38 MAPK信号通路的活化用p-p38/p38表示);培养24 h后,ELISA检测各组细胞的上清液中白细胞介素（IL）-1β的含量。结果相比于对照组,H2O2 的刺激可以上调NIH-3T3细胞中NALP3、Caspase-1及P38α mRNA的表达,NALP3及p-p38/p38蛋白的表达量,以及IL-1β分泌均增加（P均＜0.05）;抗氧化组、p38 MAPK阻断剂组及阿魏酸钠干预组相较于H2O2 刺激组,NALP3、Caspase-1及P38α mRNA的表达量以及NALP3、p-p38/p38蛋白的表达量均降低,IL-1β的释放也减少（P均＜0.05）;而抗氧化组、p38 MAPK阻断剂组及阿魏酸钠干预组间上述指标的差异无统计学意义（P＞0.05）。结论阿魏酸钠可能通过抑制p38 MAPK通路的活化降低NALP3炎性复合体、Caspase-1和IL-1β的表达,从而下调炎症级联反应。     

C-reactive protein decreases interleukin-8 production in human endothelial progenitor cells by inhibition of p38 MAPK pathway

Background C-reactive protein （CRP） has been reported to damage the vascular wall by inducing endothelial dysfunction and inflammation, and it is also speculated to have a role in attenuating angiogenic functions of human endothelial progenitor cells （EPCs）. Interleukin-8 （IL-8） is an important mediator of the paracrine mitogenic effect of EPCs which has direct angiogenic effects on mature endothelial cells. We, herein, investigated the direct effect of CRP on IL-8 production and gene expression in cultured human EPCs. Methods EPCs were isolated from the peripheral venous blood of healthy male volunteers. Cells were cultured in EndoCultTM liquid medium in the absence and presence of CRP at clinically relevant concentrations （5 to 25 μg/ml） for different durations （3 to 48 hours）. IL-8 protein and mRNA of cultured EPCs were evaluated using ELISA and real-time PCR. Results The results showed that CRP at a concentration of 10 μg/ml significantly reduced IL-8 secretion of cultured EPCs with a peak at 25 μg/ml, and also decreased mRNA expression in EPCs with a peak at 12 hours. In addition, preincubation of EPCs with SB203580, an inhibitor of p38 mitogen-activated protein kinase （MAPK） decreased CRP inhibition of IL-8 mRNA expression at 12 hours in EPCs. Conclusions Our study, for the first time, demonstrates that CRP directly inhibits EPCs IL-8 secretion, a key cytokine player of angiogenesis induced by EPCs. Inhibition occurred in part via an effect of CRP to active the p38 MAPK signal transduction pathway in EPC. The ability of CRP to inhibit EPCs IL-8 secretion may represent an important mechanism that further links inflammation to cardiovascular disease.     

Chrysanthemum indicum linné extracts attenuate the mitogenic effect of epinephrine on human HCC cells

Objective

To investigate the stimulatory effect of epinephrine(Epi) and the antagonistic effect of Chrysanthemum indicum Linné extracts (CILE) on Epi-induced growth of human hepatocellular carcinoma(HCC) cells.

Methods

The stimulatory effect of Epi and inhibitory effect of CILE on the growth of HepG2 and MHCC97H cells were investigated using a proliferation assay in correlation with β adrenergic receptor(β2-AR) blockade, a MEK1/MEK2 inhibitor, and assessment of MAPK/ERK½ intracellular activity.

Results

Epi transiently activated MAPK/ERK½ in HepG2 and MHCC97H cells, resulting in a burst of growth. The effect of Epi was significantly attenuated by ICI 118551 and U0126. CILE exhibited a dose-dependent attenuation of the stimulatory effect of Epi on the growth of both cell lines and inhibited the Epi-induced activation of MAPK/ERK½.

Conclusion

Epi, mimicking a mitogen, stimulated the growth of HepG2 and MHCC97H cells, and CILE was effective in attenuating this effect of Epi on tumor cells by inhibiting the β2-AR-mediated activation of MAPK/ERK½.     

Flagellin of Pseudomonas aeruginosa induces transforming growth factor beta 1 expression in normal bronchial epithelial cells through mitogen activated protein kinase cascades

Background  Acute lung infection due to Pseudomonas aeruginosa (P. aeruginosa) is a serious problem, especially in patients with structural lung conditions or immune compromised hosts, leading to an overwhelming threat with a high risk of morbidity and mortality. As an outcome of infection, fibrosis can be linked with chronic lung diseases. But some fibrotic manifestations, such as an irreversible decrease of lung function and fibrous bands seen on chest imaging, have been found after an acute infection with P. aeruginosa. Fibrogenesis/remodeling resulting from acute lung infection by P. aeruginosa is rarely reported. This study was designed to explore the relation between fibrogenesis/remodeling and acute infection by P. aeruginosa in vitro. We used flagellin protein from P. aeruginosa, a key initiator of acute P. aeruginosa lung infection, to elucidate mechanisms by which acute lung infection with P. aeruginosa can cause fibrogenesis/remodeling.

Methods  We studied the effect of flagellin from P. aeruginosa (flagellin for short) on the transforming growth factor beta 1 (TGF-β1) and interleukin-8 (IL-8) expression, and the possible involvement of the signaling pathway, tumor necrosis factor receptor-associated factor 6 (TRAF6)/mitogen activated protein kinase (MAPK) pathway. Flagellin was purified from the P. aeruginosa standard strain, PAO1. Normal bronchial epithelial cells BEAS-2B were challenged with different concentrations of flagellin, and cell viability assessment was performed by cell counting kit-8. BEAS-2B cells were incubated with flagellin with the specific MAPK inhibitors or TRAF6 siRNA. Cell lysates and the cultured supernatant were collected. The level of TGF-β1 and IL-8 were detected by enzyme-linked immunosorbant assay (ELISA). Western blotting was used to detect the protein levels of MAPK signal proteins p38, c-Jun NH₂-terminal kinase (JNK) and extracellular regulated kinase (ERK).

Results  Expression of TGF-β1 in BEAS-2B cells was elevated by flagellin vs. control groups ((104.3±20.8) vs. (44.6±4.4) pg/ml (P <0.01)) and was ablated by either p38 or JNK inhibitors compared with flagellin treatment ((45.1±18.8) vs. (104.3±20.8) pg/ml and (48.1±20.8) vs. (104.3±20.8) pg/ml, respectively (P <0.05)). Flagellin also elevated the expression of IL-8 in BEAS-2B cells vs. the control groups ((554.9±57.7) vs. (51.4±22.9) pg/ml (P <0.01)), and p38 MAPK inhibitors weaken the expression by flagellin ((301.1±155.1) vs. (554.9±57.7) pg/ml (P <0.05)). Western blotting revealed that all three MAPK proteins, p38, JNK and ERK were activated by flagellin challenge in an early phase, respectively in 15 minutes (P <0.01), 30 minutes (P <0.01) and 15 minutes (P <0.01). TRAF6 siRNA which decreased expression of TRAF6, altered the activation of JNK, p38, and ERK following flagellin treatment, but its influence on the expression of TGF-β1 and IL-8 has no statistical significance.

Conclusions  Flagellin from P.aeruginosa PAO1 induces TGF-β1 expression in normal bronchial epithelial cells, BEAS-2B, through the MAPK signal cascade in vitro. It suggests that the fibrogenesis/remodeling process may be initiated from an early stage of acute lung infection due to P. aeruginosa.

     

热射病小鼠大脑皮层组织中炎症细胞因子水平及 P38MAPK/P65NF-κB信号通路变化

目的：探讨热射病小鼠大脑皮层组织中白细胞介素1β（IL-1β）、白细胞介素-6（IL-6）、肿瘤坏死因子α（TNF-α）水平和P38丝裂原活化蛋白激酶（P38 MAPK）/P65核转录因子κB （P65NF-κB）信号通路的变化,并阐明其机制。方法：将60只小鼠根据随机数字法分为对照组及热射病1、6和24 h组（热射病模型小鼠出舱后1、6和24 h）,每组15只。观察各组小鼠体质量丢失和肛温,HE染色检测各组小鼠大脑皮层组织的形态表现,ELISA法测定各组小鼠大脑皮层组织中IL-1β、IL-6和TNF-α水平,Western blotting法检测各组小鼠大脑皮层组织中P38MAPK、P65NF-κB、p-P38MAPK和p-P65NF-κB蛋白表达水平。结果：与对照组比较,热射病组小鼠体质量丢失明显增加（P<0.05）,热射病1和6 h组小鼠肛温明显降低（P<0.05）。HE染色,对照组小鼠大脑皮层脑组织形态表现正常;热射病1 h组小鼠大量脑细胞核固缩、核染色深,血管被压缩变形、管壁外大量水肿;热射病6 h组小鼠核固缩细胞数量减少,血管外水肿减轻;热射病24 h组小鼠核固缩脑细胞和血管外水肿少见。与对照组比较,热射病1和6 h组小鼠大脑皮层组织中IL-1β、IL-6、TNF-α水平和p-P38MAPK、p-P65NF-κB蛋白表达水平明显升高（P<0.05）;热射病6 h组小鼠大脑皮层组织中IL-1β、IL-6、TNF-α水平和p-P38MAPK、p-P65NF-κB蛋白表达水平明显低于热射病1 h组（P<0.05）。结论：热射病小鼠大脑皮层组织中炎症细胞因子水平升高,P38MAPK/P65NF-κB信号通路激活,这种中枢神经系统炎症反应可能与其信号通路激活有关。     

丝裂原活化蛋白激酶对佛波酯诱导滋养细胞MMP-9基因表达的影响

目的 探讨佛波酯(PMA)诱导细胞滋养层细胞(CTB)MMP-9基因表达的调控机制。方法 用细胞ELISA法测定CTB细胞的蛋白激酶活性变化;用反转录聚合酶链反应检测CTB中MMP-9的基因表达。结果 100 nmol/L PMA能迅速激活CTB中丝裂原活化蛋白激酶(MAPK)家族中细胞外信号调节蛋白激酶(ERK)、c-jun氨基末端激酶(JNK)以及p38 MAPK激酶的活性。100 nmol/L PMA刺激CTB引起MMP-9 mRNA表达显著增加,能被ERK或p38 MAPK的特异性抑制剂所抑制。结论 ERK和p38 MAPK可能是PMA诱导CTB中MMP-9基因表达增加的重要调节物质。     

牛磺酸对重症急性胰腺炎大鼠枯否细胞p38MAPK信号转导通路的影响

目的 探讨牛磺酸对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠枯否细胞(KCs)P38MAPK的影响以及对分泌促炎细胞因子TNF-α和IL-1β的作用.方法 48只SD大鼠采用完全随机法分为假手术对照(SO)组、SAP组、SAP+Taut(牛磺酸)组.SAP模型通过胰胆管逆行注射5%牛磺胆酸钠诱导,造模前SAP+Taur组分别于24、12 h从尾静脉内注入牛磺酸(3 mmol/L,0.1 ml/100 g).假手术或造模后分别于12、24 h处死动物,检测其血清中AST、ALT、AMS含量;分离KCs,采用Western blot法检测P38MAPK活化情况,凝胶电泳迁移率法(EMSA)检测KCs中NF-κB DNA的表达,并用ELISA法检测KCs培养上清液中TNF-α和IL-1β蛋白含量.结果 SAP组大鼠血清中AST、ALT、AMS含量均较SO组明显升高(P<0.01);而SAP+Taur组血清中AST、ALT、AMS含量与SAP组比较,明显降低(P<0.05).SAP组各时间点大鼠KCs中p38MAPK活性显著高于SO组(P<0.01),而且NF-κB的表达也明显高于SO组(P<0.01),KCs培养上清液中TNF-α和IL-1β蛋白含量明显高于SO组(P<0.01),但SAP+Taut组大鼠KCs上述指标均显著低于SAP组.结论 牛磺酸可以抑制急性胰腺炎时KCs中p38MAPK的活化,减少NF-κB的表达,从而对促炎细胞因子TNF-α和IL-1β的分泌起抑制作用,可能具有临床应用前景.     

丝裂原活化蛋白激酶信号转导通路在金黄色葡萄球菌α-毒素所致人外周血单核细胞凋亡中的作用

目的研究丝裂原活化蛋白激酶信号转导通路在金黄色葡萄球菌α-毒素所致人外周血单核细胞凋亡中的作用。方法以Annexin V异硫氰酸荧光素/碘化丙啶双染流式细胞仪检测人外周血单核细胞的凋亡率,以Western blot法检测p38丝裂原活化蛋白激酶(MAPK)、细胞外信号调节激酶(ERK)及c-Jun N末端激酶(JNK)等蛋白的表达。结果随着α-毒素作用时间的延长,磷酸化-p38 MAPK和JNK1/2等蛋白的表达逐渐增高,而磷酸化-ERK1/2蛋白的表达不变。用SB203580和SP600125阻断p38 MAPK和JNK1/2后,单核细胞凋亡率明显降低,分别为(17.7±1.8)%和(15.3±1.6)%,与感染60 min时(35.7±3.6)%比较,差异有统计学意义(P<0.05)。结论 MAPK信号通路的成员p38 MAPK和JNK1/2在金黄色葡萄球菌的致病过程中起重要作用。     

黄芪对哮喘大鼠肺组织p38蛋白激酶表达的影响

目的 探讨支气管哮喘大鼠肺组织p38蛋白激酶（p38 MAPK）表达的变化以及黄芪注射液对其影响。方法 应用鸡卵清蛋白（OVA）腹腔注射致敏和反复超声雾化吸入刺激复制大鼠哮喘模型。随机分成3组：正常对照组、哮喘模型组和黄芪干预组。分别采用酶联免疫吸附法（ELISA）和蛋白质印迹检测支气管肺泡灌洗液（BALF）IL-5含量和肺组织磷酸化p38MAPK表达的变化,并观察BALF中EOS计数以及肺组织病理学变化。结果哮喘模型组大鼠肺组织磷酸化p38MAPK表达水平及BALF中IL-5含量和EOS计数均较正常对照组显著增加（P〈0．01）;黄芪干预组的上述改变较哮喘模型组显著降低（P〈0．01）,肺组织病理学损伤程度明显减轻。肺组织磷酸化p38 MAPK表达水平与BALF中IL-5含量和EOS计数之间分别呈显著正相关（r=0．73,0．65,P〈0．01）。结论 p38 MAPK可能参与了支气管哮喘的发病过程,黄芪对哮喘的治疗作用可能部分与抑制磷酸化p38 MAPK的表达有关。