人呼吸道合胞病毒感染对机体Th1、Th2影响的研究进展

人呼吸道合胞病毒(Human respiratory syncytial virus,HRSV)感染是儿童时期罹患病毒性毛细支气管炎和肺炎的首要原因,与高发病率、住院率、死亡率明显相关。HRSV感染引起机体免疫应答失衡是导致发病的主要因素,其引发细胞介导的免疫应答方式常见的有辅助型T淋巴细胞1型(T-helper type 1,Th1)应答和辅助型T淋巴细胞2型(T-helper type 2,Th2)应答。这两种T细胞亚型的分化途径密切相关,两者之间的失衡可能在HRSV感染的发病机制中起重要作用。进一步研究和阐明HRSV感染对机体Th1、Th2之间免疫应答的作用机制将对寻找具有治疗作用的潜在靶标、通路,设计、研制安全有效的HRSV疫苗和药物具有至关重要的推动作用。     

白细胞介素23受体、白细胞介素17A在炎症性肠病患者中的表达及临床意义

目的：通过检测白细胞介素23受体（1L-23R）及白细胞介素17A（IL-17A）在炎症性肠病（IBD）患者肠黏膜及血清中的表达水平,探讨其在IBD发病过程中的作用及意义。方法：收集32例克罗恩病（CD）患者、29例溃疡性结肠炎（UC）患者及27例对照者的内镜肠黏膜活检标本,采用荧光定量PCR技术检测肠黏膜内IL-23R、IL-17AmRNA的表达情况,免疫组化技术分析IL-23R、IL-17A在肠黏膜中的原位表达。结果：与健康对照组相比,CD及UC患者肠黏膜组织内IL-23RmRNA表达显著增高（P〈0．05）,CD及UC组间的表达量差异无统计学意义（P〉0．05）。CD及UC患者肠黏膜组织内IL-17AmRNA表达显著增高（P〈0．05）,CD组肠黏膜组织内IL．17AmRNA表达显著高于uc组（P〈0．05）。免疫组化分析显示IL-23R阳性细胞在CD与uc肠黏膜固有层内有较多表达,较正常黏膜内的肠上皮细胞相比,CD及UC患者肠黏膜IL-23R蛋白表达量最著增高（P〈0．05）,UC及CD组间的表达量差异无统计学意义（P〉0．05）。IL-17A阳性细胞在CD与UC肠黏膜固有层内有较多表达,较正常黏膜内的肠上皮细胞相比,CD及UC患者肠黏膜IL-17A蛋白表达量最著增高（P〈0．05）。结论：IL．23R及IL-17A在IBD患者肠黏膜中表达显著增高,提示IL-23R及IL-17A表达异常与IBD的发生发展密切相关,有可能成为IBD治疗的新靶点。     

白细胞介素23受体、白细胞介素17A在炎症性肠病患者中的表达及临床意义

目的:通过检测白细胞介素23受体(IL-23R)及白细胞介素17A(IL-17A)在炎症性肠病(IBD)患者肠黏膜及血清中的表达水平,探讨其在IBD发病过程中的作用及意义。方法:收集32例克罗恩病(CD)患者、29例溃疡性结肠炎(UC)患者及27例对照者的内镜肠黏膜活检标本,采用荧光定量PCR技术检测肠黏膜内IL-23R、IL-17AmRNA的表达情况,免疫组化技术分析IL-23R、IL-17A在肠黏膜中的原位表达。结果:与健康对照组相比,CD及UC患者肠黏膜组织内IL-23R mRNA表达显著增高(P<0.05),CD及UC组间的表达量差异无统计学意义(P>0.05)。CD及UC患者肠黏膜组织内IL-17A mRNA表达显著增高(P<0.05),CD组肠黏膜组织内IL-17AmRNA表达显著高于UC组(P<0.05)。免疫组化分析显示IL-23R阳性细胞在CD与UC肠黏膜固有层内有较多表达,较正常黏膜内的肠上皮细胞相比,CD及UC患者肠黏膜IL-23R蛋白表达量最著增高(P<0.05),UC及CD组间的表达量差异无统计学意义(P>0.05)。IL-17A阳性细胞在CD与UC肠黏膜固有层内有较多表达,较正常黏膜内的肠上皮细胞相比,CD及UC患者肠黏膜IL-17A蛋白表达量最著增高(P<0.05)。结论:IL-23R及IL-17A在IBD患者肠黏膜中表达显著增高,提示IL-23R及IL-17A表达异常与IBD的发生发展密切相关,有可能成为IBD治疗的新靶点。     

白介素23 及Th17 细胞在炎症性肠病的作用

炎症性肠病(Inflammatory Bowel Diseases,IBD),是一组病因未明的累及胃肠道的慢性炎症性疾病,一般指克罗恩病(Crohn’sdisease,CD)和溃疡性结肠炎(ulcerative colitis,UC)。目前认为它是由多种因素相互作用所致的一种自身免疫性疾病,主要包括免疫、环境以及遗传等因素,其中免疫在IBD的发生过程中起着极其重要的作用。以往研究认为与T辅助细胞(T Helper cells)Th1或Th2细胞反应的增强或减弱有关。然而最近研究发现一类新细胞亚群,称为Th17细胞,与之相关的细胞因子可导致包括肠道在内的多脏器病变。Th17细胞分化过程中又需要IL-23的参与,因此IL-23/Th17细胞在炎症性肠病患者肠道内过度表达可以解释肠组织损伤的新途径,并为制定新的治疗策略提出依据。本文就IL-23/Th17轴在炎症性肠病中的作用的研究进展作一综述。     

p38 MAPKα/β和ERK1/2在心肌缺氧预处理信号传递中的不同作用

建立培养乳鼠心肌细胞的缺氧／复氧(A／R)损伤模型和缺氧预处理(APC)模型,以细胞存活率、细胞内超氧化物趋化酶(SOD)活性、丙二醛(MDA)含量、培养上清液乳酸脱氢酶(LDH)活性作为反映心肌细胞损伤的指标。采用细胞外信号调节蛋白激酶(ERK1／2)抑制剂PD98059及丝裂素活化蛋白激酶p38α/β(p38α/β)阻滞剂SB203580干预模型,并以胶内原位磷酸化法测定ERK1／2和p38活性,借以探讨ERK1／2和p38α/β在缺氧预处理保护机制中的作用。结果表明：(1)在APC组,于预处理的缺氧时相给予PD98059,可以完全消除APC的延迟保护作用;在A／R组的缺氧时相加入PD98059对细胞损伤无影响;(2)在APC组的预处理缺氧时相给予p38α／β抑制剂SB203580并不能消除APC的保护作用,而在A／R组的持续缺氧时相给予SB203580则可显著减轻缺氧对细胞的损伤;(3)ERK1／2和p38总活性测定表明,缺氧可激活ERK1／2和p38,它们的活性在缺氧后4h时达到高峰,而经过APC处理后,两者活性高峰提前于缺氧后3h时出现,且峰值显著降低。上述结果提示,预处理过程中ERK1／2的激活可能是缺氧预处理延迟保护机制中细胞信号传递的重要环节,预处理阶段p38α/β的活化不参与APC诱导的延迟保护信号传递过程,p38的过度激活可能是缺氧／复氧损伤过程中的一个致损伤参与因素,而预处理抑制随后持续缺氧阶段p38的过度激活可能是其保护机制的一个环节。     

p38 MAPK信号传导通路

丝裂原活化蛋白激酶（ｍｉｔｏｇｅｎ－ａｃｔｉｖａｔｅｄｐｏｒｏｔｅｉｎｋｉｎａｓｅ,ＭＡＰＫ）介导了生长、发育,分裂,死亡,以及细胞间的功能同步等多种细胞生理功能,在哺乳动物细胞中已发现和克隆了ＥＲＫ、ＪＮＫ／ＳＡＰＫ,ＥＲＫ５／ＢＭＫ１和ｐ３８／ＲＫ四个ＭＡＰＫ亚族,这些新的ＭＡＰＫ介导了物理,化学反激,细菌产物,炎性细胞因子等多种刺激引起的细胞反应,ｐ３８亚族至少包括ｐ３８（α）,ｐ３８β,ｐ     

Notch通路与基质金属蛋白酶在软骨肉瘤中的表达及意义

目的 研究软骨肉瘤组织中Notch通路、p38丝裂原活化蛋白激酶(MAPK)及基质金属蛋白酶(MMPs)的表达情况,探讨它们在软骨肉瘤间质浸润中的作用机制.方法 收集正常软骨组织标本10例、内生性软骨瘤标本23例和软骨肉瘤标本32例,分别用免疫组化、Western blot和real-time PCR检测Notch1、Jagged1、MMP-1、MMP-13、p38 MAPK及p-p38 MAPK的表达情况.结果 与正常软骨组织相比,Notch1、Jagged1、MMP-1、MMP-13及p-p38 MAPK在内生性软骨瘤表达部分升高,在软骨肉瘤表达均明显增加(P＜0.01).p38 MAPK在正常软骨组织、内生性软骨瘤及软骨肉瘤组织中表达无明显差异(P＞0.05).结论 Notch通路和p38 MAPK通过调节基质金属蛋白酶在软骨肉瘤中的表达,来增加软骨肉瘤的浸润转移能力.     

Endogenous δ-Opioid and ORL1 Receptors Couple to Phosphorylation and Activation of p38 MAPK in NG108-15 Cells and This Is Regulated by Protein Kinase A and Protein Kinase C

The p38 mitogen-activated protein kinase (MAPK) cascade transduces multiple extracellular signals from cell surface to nucleus and is employed in cellular responses to cellular stresses and apoptotic regulation. The involvement of the p38 MAPK cascade in opioid- and opioid receptor-like receptor-1 (ORL1) receptor-mediated signal transduction was examined in NG108-15 neuroblastoma x glioma hybrid cells. Stimulation of endogenous delta-opioid receptor (DOR) or ORL1 resulted in activation of p38 MAPK. It also induced the activation of extracellular signal-regulated kinases (ERKs), another member of the MAPK family, with slower kinetics. Activation of p38 MAPK was abolished by selective antagonists of DOR or ORL1, pretreatment with pertussis toxin, or SB203580, a specific inhibitor of p38 MAPK. Inhibition of p38 MAPK had no significant effect on opioid-induced ERK activation, indicating that p38 MAPK activity was not required for ERK activation, though its stimulation preceded ERK activation. Inhibition of protein kinase A (PKA) strongly diminished p38 activation mediated by DOR or ORL1 but had no significant effect on ERK activation, and protein kinase C (PKC) inhibitors potentiated stimulation of p38 while inhibiting activation of ERKs. Taken together, our results provide the first evidence for coupling of DOR and ORL1 to the p38 MAPK cascade and clearly demonstrate that receptor-mediated activation of p38 MAPK both involves PKA and is negatively regulated by PKC.     

Direct evidence for leptin-induced lipid oxidation independent of long-form leptin receptor

Leptin administration has been shown to enhance muscle lipid oxidation in relation to the energy expenditure. Both long-form (Ob-R_L) and short-form leptin receptors (Ob-R_S) are expressed in skeletal muscle, but the role of Ob-R_S is unclear. In the present study, the role of Ob-R_S in leptin-induced lipid oxidation in skeletal muscles was investigated using primary murine myotubes from m/m and db/db mice. Primary myotubes were treated with leptin (0.1, 1, 10, 100 nM) for 24 h. Lipid oxidation was determined by ¹⁴CO₂ production rate from [1-¹⁴C] palmitate. Leptin was found to increase lipid oxidation in a dose- and time-dependent manner in db/db myotubes as well as in m/m myotubes. Leptin significantly increased phosphorylation of JAK2 and STAT3 in both types of myotube. Leptin-induced lipid oxidation was abolished by STAT3 siRNA. To investigate the mechanism underlying leptin-induced lipid oxidation, the effects of pharmacological inhibitors were examined. JAK2 or p38 MAPK inhibitor suppressed leptin-induced lipid oxidation and decreased STAT3 phosphorylation in both types of myotube, respectively. Leptin significantly increased phosphorylation of p38 MAPK, and leptin-induced lipid oxidation was abolished by treatment with p38 MAPK siRNA in both types of myotube. These results suggest that leptin induces lipid oxidation in skeletal muscle through the JAK2/p38 MAPK/STAT3 signaling pathway via not only Ob-R_L but also Ob-R_S.     

p38丝裂原素激活的蛋白激酶在调节低氧诱导人内皮细胞分泌血管内皮生长因子过程中的作用

血管内皮细胞中血管内皮生长因子(vascular endothelial growthfactor,VEGF)的合成增加在促进血管新生的过程中起着非常重要的作用.然而低氧诱导VEGF分泌的细胞内信号转导机制还不是很清楚.人脐静脉内皮细胞系(ECV304)在低氧或常氧的状态下培养12～24 h后分别用实时定量PCR和Western blot的方法来检测VEGF mRNA的表达及ERK1/2和p38激酶的磷酸化水平.分泌到培养液中的VEGF蛋白用酶联免疫吸附(ELISA)的方法来检测.业已报道,ERK的抑制剂PD98059能够抑制低氧诱导的VEGF基因的表达,根据这个报道,我们发现在低氧情况下,ECV304细胞的ERK1/2磷酸化水平增高以及VEGF的合成增加等这些变化也能被PD98059所抑制.本次实验的新发现是p38激酶的激活在低氧诱导VEGF合成增加中的作用.p38激酶的抑制剂SB202190能抑制低氧诱导的VEGF合成增加.这些数据首次直接证实了p38激酶在低氧诱导人内皮细胞分泌VEGF增加过程中的作用.     

AMPK induces MUC5B expression via p38 MAPK in NCI-H292 airway epithelial cells

Adenosine monophosphate-activated protein kinase (AMPK) is a well-known serine/threonine kinase that has been implicated in modulation of glucose and fatty acid metabolism. Recent reports have also implicated AMPK in modulation of mucin secretion. In this study, the effects and signaling pathways of AMPK on MUC5B expression were investigated in human NCI-H292 airway epithelial cells. Metformin, as an activator of AMPK, induced MUC5B expression in a dose-dependent manner. Compound C, as an inhibitor of AMPK, inhibited metformin-induced MUC5B expression in a dose-dependent manner. Metformin significantly activated phosphorylation of AMPK; compound C inhibited metformin-activated phosphorylation of AMPK. Without treatment with metformin, there was no difference in MUC5B mRNA expression between Ad-dnAMPK transfected and wild-type adenovirus transfected NCI-H292 cells. However, after treatment with metformin, MUC5B mRNA expression was increased in wild-type adenovirus transfected NCI-H292 cells; MUC5B mRNA expression was significantly decreased in Ad-dnAMPK transfected NCI-H292 cells. Metformin activated phosphorylation of p38 mitogen-activated protein kinase (MAPK); compound C inhibited metformin-activated phosphorylation of p38 MAPK. SB203580, as an inhibitor of p38 MAPK, significantly inhibited metformin-induced MUC5B mRNA expression, while U0126, as an inhibitor of ERK1/2 MAPK, had no effect. In addition, knockdown of p38 MAPK by p38 MAPK siRNA significantly blocked metformin-induced MUC5B mRNA expression. In conclusion, results of this study show that AMPK induces MUC5B expression through the p38 MAPK signaling pathway in airway epithelial cells.     

p38丝裂原活化蛋白激酶活性放射自显影测定方法的建立和应用

建立p38丝裂原活化蛋白激酶（mitogen-activated protein kinase, MAPK）放射自显影激酶活性测定方法,并应用于血管内皮细胞中p38 MAPK活性动态变化的研究.结果表明放射自显影激酶活性测定方法具有很好的量效关系、灵敏性和特异性.在脂多糖（lipopolysaccharide, LPS）刺激的血管内皮细胞,p38 MAPK在LPS刺激15 min后活性增高,30～60 min达高峰,120 min后活性逐渐下降,较好地反映了LPS刺激的内皮细胞中p38 MAPK活性的动态变化.国内实验室完全有可能和条件,建立本国的放射自显影激酶活性测定方法,并应用于信号转导的研究.     

Paralytic peptide activates insect humoral immune response via epidermal growth factor receptor

Paralytic peptide (PP) activates innate immunity of silkworm Bombyx mori, inducing production of anti-microbial peptides (AMPs) and phagocytosis-related proteins; however the signal pathways of PP-dependent immune responses are not clear. In present study, we characterized BmE cells as a PP-responsive cell line by examining the expression of AMP genes and activation of p38 mitogen-activated protein kinase (p38 MAPK) under PP stimulation, and we also found PP directly binds to BmE cell membrane. Then we found that PP-dependent expression of AMP genes is suppressed by tyrosine kinase inhibitor (genistein) both in BmE cells and in fat body of silkworm larvae. Moreover, the specific tyrosine kinase epidermal growth factor receptor (EGFR) inhibitor (AG1478) attenuates PP-induced expression of AMP genes in BmE cells and fat body of silkworm and RNA interference (RNAi) to BmEGFR also suppresses PP-induced expression of AMP genes. Furthermore, the PP-induced p38 MAPK phosphorylation is inhibited by AG1478. Our results suggest that BmE cells can be used as a cell model to investigate the signal pathway of PP-dependent humoral immune response and receptor tyrosine kinase EGFR/p38 MAPK pathway is involved in the production of AMPs induced by PP.     

The cell adhesion molecule neuroplastin-65 inhibits hippocampal long-term potentiation via a mitogen-activated protein kinase p38-dependent reduction in surface expression of GluR1-containing glutamate receptors

Neuroplastin-65 is a brain-specific, synapse-enriched member of the immunoglobulin (Ig) superfamily of cell adhesion molecules. Previous studies highlighted the importance of neuroplastin-65 for long-term potentiation (LTP), but the mechanism was unclear. Here, we show how neuroplastin-65 activation of mitogen-activated protein kinase p38 (p38MAPK) modified synapse strength by altering surface glutamate receptor expression. Organotypic hippocampal slice cultures treated with the complete extracellular fragment of neuroplastin-65 (FcIg1-3) sustained an increase in the phosphorylation of p38MAPK and an inability to induce LTP at hippocampal synapses. The LTP block was reversed by application of the p38MAPK inhibitor SB202190, suggesting that p38MAPK activation occurred downstream of neuroplastin-65 binding and upstream of the loss of LTP. Further investigation revealed that the mechanism underlying neuroplastin-65-dependent prevention of LTP was a p38MAPK-dependent acceleration of the loss of surface-exposed glutamate receptor subunits that was reversed by pretreatment with the p38MAPK inhibitor SB202190. Our results indicate that neuroplastin-65 binding and associated stimulation of p38MAPK activity are upstream of a mechanism to control surface glutamate receptor expression and thereby influence plasticity at excitatory hippocampal synapses.     

Mycophenolic acid inhibits mesangial cell activation through p38 MAPK inhibition

Mesangial cell (MC) proliferation and extracellular matrix (ECM) accumulation are major pathologic features of chronic renal disease including chronic allograft nephropathy (CAN). Mycophenolic acid (MPA), a potent immunosuppressant, has emerged as a treatment to prevent CAN because it inhibits MC proliferation and ECM synthesis, but the mechanism involved has not been clarified. The present study examined relative role of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (p38 MAPK) activation in inhibitory effect of MPA on MC activation. Growth arrested and synchronized primary rat MC (passages 7-11) were stimulated by PDGF 10 ng/ml in the presence and absence of clinically attainable dose of MPA (0-10 microM). Cell proliferation was assessed by [(3)H]thymidine incorporation, fibronectin and the activation of ERK and p38 MAPK by Western blot analysis, and total collagen by [(3)H]proline incorporation. PDGF increased cell proliferation by 4.6-fold, fibronectin secretion by 3.2-fold, total collagen synthesis by 1.8-fold, and the activation of ERK and 38 MAPK by 5.6-fold and 3.1-fold, respectively, compared to control. MPA, at doses inhibiting PDGF-induced MC proliferation and ECM synthesis, effectively blocked p38 MAPK activation but reduced ERK activation by 23% at maximal concentration tested (10 microM). Exogenous guanosine partially reversed the inhibition of MPA on p38 MAPK activation. Inhibitor of ERK or p38 MAPK suppressed PDGF-induced MC proliferation and ECM synthesis. In conclusion, MPA inhibits p38 MAPK activation leading to inhibiting proliferation and ECM synthesis in MC. Guanosine reduction is partially responsible for inhibitory effect of MPA on p38 MAPK activation in MC.