The relationship between p38MAPK and apoptosis during paclitaxel resistance of ovarian cancer cells

Summary To investigate the relationship between p38 mitogen-activated protein kinase (p38MAPK) and cell apoptosis during the paclitaxel resistance of ovarian carcinoma cell lines, flow cytometry (FCM) and PI staining were employed to determine the effect of p38MAPK inhibitor SB203580 on the apoptosis of A2780/Taxol cells, a drug-resistant human ovarian carcinoma cell line. p38MAPK protein expression in SB203580-treated cells was immunochemically measured. The 50% inhibition concentration (IC₅₀) of paclitaxel on A2780/Taxol cells was determined by MTT assay. MDR-1 mRNA, and expression of p38MAPK and phospho-p53 protein were detected by RT-PCR and Western blotting, respectively. The apoptosis rate of A2780/Taxol cells was (19.7±1.04)% 24 h after SB203580 treatment. A significant difference in apoptosis rate was found among experiment group, control group and untreated group (P<0.05). The relative reversal rate of A2780/Taxol cells to paclitaxel was (57.18±2.01)%. As compared with the control group and the untreated group, p38MAPK protein and MDR-1 mRNA in SB203580-treated cells was substantially decreased. The expression of p53 protein was significantly increased. It is concluded that p38MAPK pathway is related to paclitaxel resistance of ovarian carcinoma, and blockade of this pathway can promote the apoptosis of the drug-resistant cells and reverse the drug-resistance. Moreover, p38MAPK-mediated apoptosis in paclitaxel-resistant ovarian carcinoma cells depends on the activation of p53. This project was supported by a grant from R&D program of Heilongjiang Province (No. GB05C402-11).     

The Relationship between p38MAPK and Apoptosis during Paclitaxel Resistance of Ovarian Cancer Cells

To investigate the relationship between p38 mitogen-activated protein kinase (p38MAPK) and cell apoptosis during the paclitaxel resistance of ovarian carcinoma cell lines, flow cytometry (FCM) and PI staining were employed to determine the effect of p38MAPK inhibitor SB203580 on the apoptosis of A2780/Taxol cells, a drug-resistant human ovarian carcinoma cell line. p38MAPK protein expression in SB203580-treated cells was immunochemically measured. The 50% inhibition concentration (IC50) of paclitaxel on A2780/Taxol cells was determined by MTT assay. MDR-1 mRNA, and expression of p38MAPK and phospho-p53 protein were detected by RT-PCR and West- ern blotting, respectively. The apoptosis rate of A2780/Taxol cells was (19.7±1.04)% 24 h after SB203580 treatment. A significant difference in apoptosis rate was found among experiment group, control group and untreated group (P<0.05). The relative reversal rate of A2780/Taxol cells to pacli- taxel was (57.18±2.01)%. As compared with the control group and the untreated group, p38MAPK protein and MDR-1 mRNA in SB203580-treated cells was substantially decreased. The expression of p53 protein was significantly increased. It is concluded that p38MAPK pathway is related to pacli- taxel resistance of ovarian carcinoma, and blockade of this pathway can promote the apoptosis of the drug-resistant cells and reverse the drug-resistance. Moreover, p38MAPK-mediated apoptosis in pa- clitaxel-resistant ovarian carcinoma cells depends on the activation of p53.     

Targeting of p38 Mitogen-activated Protein Kinases to Early Growth Response gene 1 （EGR-1） in the Human Paclitaxel-resistance Ovarian Carcinoma Cells

To investigate the relationship between the expression of early growth response gene 1 (EGR-1) and p38MAPK pathway in the paclitaxel resistance of ovarian carcinoma cells, the effect of p38MAPK inhibitor SB203580 on cell apoptosis was examined by using Hoechst 33258 staining. The intracellular Rh123 (Rhodamine 123) accumulation was detected by the flow cytometry (FCM). The 50% inhibition concentration (IC50) of paclitaxel for A2780/Taxol cells was determined by MTT method. Electrophoretic motility shift assay (EMSA) was employed to examine the EGR-1DNA binding activity. MDR1 and EGR-1 mRNA were assessed by RT-PCR. The expressed of p-gp, phos- phorylated p53 and p38 were detected by Western blotting. SB203580 could remarkably promote the apoptosis of A2780/Taxol cells, and the cell apoptosis was in a time-dependent manner. Cellular Rh123 accumulation was increased, and the IC50 of paclitaxel for A2780/Taxol cells was decreased significantly. A2780/Taxol cell line after SB203580 treatment was shown to have a significantly higher level of EGR-1 DNA binding activity. SB203580 down-regulated the activity of p38MAPK pathway, but up-regulated EGR-1 expression. SB203580 significantly increased the level of cellular phosphorylated p53 protein, but decreased the p-gp protein level and MDR1 mRNA level in A2780/Taxol cells. There existed a close relationship between p38MAPK pathway and the paclitaxel resistance of ovarian carcinoma cells. The expression of EGR-1 mediated by p38MAPK pathway plays a critical role in paclitaxel resistance of ovarian carcinoma cells.     

TNF-α 通过 p38 丝裂原活化蛋白激酶信号通路对小胶质细胞HMGB1 表达的调控作用

目的：观察P38丝裂原活化蛋白激酶(p38 mitogen-activated protein kinase,p38 MAPK)抑制剂SB203580对 TNF-α诱导的原代培养大鼠小胶质细胞高迁移率族蛋白B1(high mobility group protein B1,HMGB1)表达的影响。方法： 采用原代培养大鼠小胶质细胞,设立对照组、TNF-α组(25 ng/mL)、TNF-α(25 ng/mL)+SB 203580组(10 μmol/L)、SB 203580组(10 μmol/L),各组细胞经药物处理16 h后分别用ELISA法检测细胞培养上清中HMGB1的表达情况,Western 印迹检测细胞HMGB1和磷酸化p38MAPK表达情况,用反转录PCR检测HMGB1 mRNA表达。结果：经TNF-α刺激 后,大鼠小胶质细胞及其培养上清液中HMGB1蛋白表达增高;SB 203580可抑制TNF-α诱导的磷酸化p38 MAPK表达 (P<0.01),同时下调HMGB1mRNA和HMGB1蛋白的表达。结论：TNF-α可诱导小胶质细胞晚期炎症因子HMGB1的表 达,并且其诱导机制与p38 MAPK被快速激活相关。     

p38MAPK信号通路抑制剂对NMDA诱导的体外培养的皮层神经元损伤的保护作用及机制

目的 观察MK801及SB203580对N-甲基-D-天（门）冬氨酸（NMDA）诱导的皮层神经元损伤的影响, 探讨p38丝裂原活化蛋白激酶（p38MAPK)信号通路在神经元损伤中的作用和机制。方法 培养7d的新生SD大鼠皮层神经元随机分为对照组、NMDA损伤组、MK801干预组、SB203580干预组、联合干预组（SB203580+MK801）。MTT比色实验评价细胞生存力,乳酸脱氢酶(LDH)释放率测定细胞损伤程度,吖啶橙/溴化乙锭 (AO/EB) 双重荧光染色观察细胞凋亡形态和数目,Western blotting检测大鼠皮层神经元各组p38MAPK、BCL-2和BAX表达情况。结果 与对照组比较,NMDA损伤组神经细胞存活力降低、培养上清液中LDH含量增加、凋亡细胞增多、p38MAPK和BAX表达增加(P均＜0.01),BCL-2表达降低(P＜0.05);与NMDA损伤组比较,各个干预组细胞生存力提高、LDH释放率降低、凋亡减少、p38MAPK及BAX的表达减少、BCL-2表达增多(P均＜0.01)。结论 MK801,SB203580对NMDA诱导的皮质神经元损伤具有保护作用,p38MAPK通路可能参与介导MK801的保护作用,其共同机制是通过抑制p38MAPK信号通路介导的凋亡相关蛋白实现的。     

p38MAPK/eNOS信号通道在胰高血糖素样肽-1抑制AGEs诱导的人脐静脉内皮细胞凋亡中的作用

目的探讨p38MAPK信号通道在胰高血糖素样肽-1（GLP-1）拮抗糖基化终末产物（AGEs）诱导的人脐静脉内皮细胞凋亡
的作用。方法实验组分为对照组、AGEs组、GLP-1组、AGEs+GLP-1组、AGEs+抑制剂组及AGEs+GLP-1+抑制剂组,western
blot技术检测p-p38MAPK/p38MAPK、p-eNOS/eNOS蛋白表达情况,Annexin V/PI流式检测细胞凋亡率。结果与对照相比较,
单独加入AGEs或GLP-1可分别导致p-p38MAPK蛋白表达水平明显上升（P=0.001）或下降（P<0.001）;与对照组相比AGEs可
显著降低p-eNOS表达水平（P=0.007）,而予以GLP-1或p38MAPK抑制剂（SB203580）预处理后,受抑制的eNOS蛋白表达水平
再次显著升高（P=0.004）;在AGEs 组加入SB203580 或GLP-1 预处理后,AGEs诱导的细胞凋亡率均显著下降（P<0.001,P<
0.001）。结论GLP-1至少部分通过抑制p38MAPK蛋白磷酸化,上调磷酸化eNOS蛋白的表达,对人脐静脉内皮细胞起到抗凋
亡的保护作用。
     

丝裂原活化蛋白激酶在力达霉素抑制鼠骨髓瘤细胞增殖和诱导凋亡中的作用

目的: 研究力达霉素(LDM)对鼠骨髓瘤细胞丝裂原活化蛋白激酶(MAPKs) 信号传导通路的影响及MAPKs在LDM抑制鼠骨髓瘤细胞增殖和诱导凋亡中的作用,为LDM治疗人多发性骨髓瘤的研究提供依据。方法: 选取处于对数生长期鼠骨髓瘤细胞株SP2/0,随机分为空白对照组、4种不同浓度LDM组,采用Western blotting 方法检测各组细胞48 h后MAPK家族的三个主要成员c-Jun氨基末端激酶(JNK)、细胞外信号调节激酶(ERK)和p38 MAPK的表达水平。选取处于对数生长期SP2/0,随机分为对照组、LDM组、SP600125组(JNK抑制剂)、SB203580组(p38抑制剂)、U0126组(ERK抑制剂)、LDM+SP600125组、LDM+SB203580组和LDM+U0126组,采用MTS法和流式细胞术分别检测各组细胞增殖和凋亡情况。结果: 细胞培养48 h后,不同浓度LDM组JNK、ERK和p38 MAPK的表达水平高于空白对照组（P<0.05）;各抑制剂组细胞增殖率和细胞凋亡率与空白对照组比较差异无统计学意义(P>0.05),即对细胞的增殖抑制和凋亡诱导作用均不明显;但LDM+SP600125组、LDM +SB203580组LDM对细胞的增殖抑制和凋亡诱导作用均降低（P<0.05）,而LDM+U0126组LDM对细胞的增殖抑制和凋亡诱导作用则增强（P<0.05）。结论: LDM能够通过激活JNK、p38 MAPK抑制鼠骨髓瘤细胞SP2/0细胞增殖,诱导其凋亡。     

p38MAPK抑制剂对兔脑血管痉挛病理变化的影响

目的 观察兔脑血管痉挛(CVS)后基底动脉病理学改变、p38MAPK的表达及其抑制剂SB203580对脑血管痉挛的影响,以探讨蛛网膜下腔出血(SAH)后CVS细胞信号通路转导机制.方法 ①采用二次枕大池注血建立兔CVS模型.②采用免疫组织化学技术动态观察兔基底动脉血管壁组织病理改变,观察使用SB203580干预后对病理...     

INVOLVEMENT OF p38 MITOGEN-ACTIVATED PROTEIN KINASE IN E.Coli-INDUCED U937 APOPTOSIS

APOPTOSIS is a highly regulated and orderedprocess that plays a central role in elim inatingunnecessary cells in normal development andhomeostasis·1Increasing numbers of pathogens, includingE·coli, have been found to modulate host cell apoptosisand ther…     

P38MAPK信号通路对大鼠肝星状细胞凋亡的影响

〗［摘 要］
目的：探讨P38MAPK信号传导通路在乙醛刺激的大鼠肝星状细胞株（HSC-T6）凋亡过程中的作用及P38蛋白表达的变化,为肝纤维化的临床治疗提供依据。方法：实验设阴性对照组（HSC-T6加含10%小牛血清的DMEM培养液）、乙醛组（对照组基础上加乙醛）和实验组（乙醛组基础上加P38MAPK抑制剂SB203580,使其终浓度为4、8、16 μmol·L^-1）,流式细胞术（FCM）检测细胞凋亡率;Western blotting法检测磷酸化P38MAPK表达水平,SABC法检测caspase-3蛋白表达。结果：与对照组比较,乙醛组HSC-T6的凋亡率和caspase-3蛋白阳性表达率均降低（P<0.05或P<0.01）,P38MAPK磷酸化水平表达增高（P<0.01）。抑制剂SB203580作用后,细胞凋亡率逐渐增高(P<0.01);P38MAPK磷酸化水平降低(P<0.01);caspase-3蛋白水平升高（P<0.01）;且随剂量的增加,磷酸化水平不断降低,蛋白表达水平不断升高。结论：P38MAPK抑制剂SB203580能促使乙醛刺激的HSC-T6凋亡,且凋亡的发生可能与SB203580抑制P38MAPK的磷酸化途径和caspase-3的活化有关。     

XIAP基因与耐紫杉醇卵巢癌细胞A2780/Taxol耐药关系的研究

目的 探讨X连锁凋亡抑制蛋白（XIAP）基因与卵巢癌对紫杉醇耐药的相关性。方法 以5、10、20、40、80、160、320 ng/mL的紫杉醇处理卵巢癌紫杉醇敏感细胞A2780和耐药细胞A2780/T,噻唑蓝（MTT）比色法检测各组细胞的抑制率（IR）, 逆转录实时荧光定量PCR（RT-qPCR）、蛋白质印记（Western blot）检测紫杉醇100 ng/mL处理A2780和A2780/T细胞后XIAP基因和蛋白的表达;将A2780/T细胞分为空转染组（转染空载体质粒）、小干扰RNA（siRNA）-XIAP（siRNA-XIAP）组（转染siRNA-XIAP质粒）、非特异性转染组（转染非特异性质粒）、空白对照组（不转染质粒）,RT-qPCR和Western blot检测各组细胞XIAP基因和蛋白的表达,并加入含不同质量浓度的紫杉醇（0、1 000、1 500、2 000、2 500 ng/mL）,流式细胞仪检测细胞凋亡率。结果 不同质量浓度紫杉醇处理后,A2780细胞IR随紫杉醇质量浓度的增加而增高（P<0.05）,A2780/T细胞IR无明显变化。紫杉醇100 ng/mL处理A2780和A2780/T细胞后,A2780细胞XIAP mRNA的表达低于紫杉醇未处理组（P<0.05）,A2780/T细胞中XIAP mRNA的表达与紫杉醇未处理组差异无统计学意义(P>0.05),但A2780/T细胞XIAP mRNA和蛋白表达均高于A2780紫杉醇处理组（P均<0.05）;siRNA-XIAP组XIAP mRNA和蛋白的表达均低于其他各组（P<0.05）,在紫杉醇2 000 ng/mL及2 500 ng/mL作用下,siRNA-XIAP组凋亡率高于其他各组（P<0.05）。结论 卵巢癌对紫杉醇耐药与XIAP基因的高表达有关,特异性的siRNA可通过降低XIAP的表达,促进细胞凋亡,增加耐药癌细胞对紫杉醇的敏感性。     

P38通路对帕金森病小鼠模型黑质环氧合酶-2、半胱氨酸蛋白酶-3表达的影响

目的 研究P38MAPK通路在1-甲基-4-苯基-1,2,3,6四氢吡啶(MPTP)所致亚急性帕金森病(PD)小鼠模型中对黑质环氧合酶-2(COX-2)、半胱氨酸蛋向酶-3(caspase-3)表达调控作用.方法 采用MPTP制备PD小鼠模型,观察行为学、免疫组化和免疫蛋白印记法观察小鼠黑质酪氨酸羟化酶(TH)、COX-2、caspase-3和磷酸化P38MAPK(P-P38MAPK)的变化,及给予P38MAPK抑制剂SB203580后对上述变化的影响.结果 模型7 d组小鼠出现典型的PD样症状,黑质区TH阳性神经元和蛋白水平分别下降约65%和75%(P<0.01);模型3 d组小鼠黑质区COX-2、P-P38MAPK、caspase-3阳性细胞数及蛋白水平显著增加.TH阳性神经元明显丢失;经P38MAPK抑制剂SB203580处理后,上述变化均显著减轻(P<0.01).结论 在MPTP所致亚急性小鼠PD模型中,P38MAPK通路对黑质区炎症与凋亡可能有重要调控作用,SB203580对PD小鼠具有一定神经保护作用.

Abstract：

Objective To investigate the effect of p38 mitogen-activated protein kinase (p38MAPK) on the expression of COX-2 and caspase-3 in the substania nigra (SN) of mice with MPTP-induced Parkinson disease (PD). Methods C57BL/CN mice were treated with MPTP to prepare a subacute PD model, and their behavioral changes following the treatment were observed. Immunohistochemistry and Western blotting were performed to detect the expression of tyrosine hydroxylase (TH), COX-2 and phosphorylation of P38MAPK in the SN and their changes following treatment with SB203580, a specific inhibitor of P38MAPK. Results The 7-day model group showed typical symptoms of PD with decrements of TH-positive neurons and TH protein level in the SN of the midbrain by about 65% and 75%, respectively (P<0.01). In the 3-day model group, the COX-2-, caspase-3- and phosphorylated P38MAPK-immunoreactive cells and their protein levels in the SN increased markedly with obvious loss of TH-positive neurons. Administration of SB203580 obviously lessened the above changes (P<0.0l). Conclusion P38MAPK regulates the inflammation and apoptosis in the SN of the mouse model of subacute PD, and SB203580 may provide some neuroprotective effect.     

TWEAK通过P38MAPK途径促进大鼠心肌成纤维细胞Ⅰ型胶原和MMP-1的表达

目的 探讨肿瘤坏死因子样凋亡微弱诱导剂(TWEAK)影响心肌成纤维细胞(CFs)中Ⅰ型胶原和基质金属蛋白酶1(MMP-1)表达的作用机制。方法 取Wistar新生大鼠CFs,加入重组人TWEAK(rhTWEAK)及P38MAPK抑制剂(SB203580)干预,将实验分为① 对照组：不加干预因素;② TWEAK组：加入100ng/mL TWEAK;③ TWEAK+SB203580组：加入100ng/mLTWEAK+SB203580。 采用MTT法检测CFs增殖;Western blot法检测Ⅰ型胶原蛋白及磷酸化P38MAPK(P-P38MAPK)蛋白表达;qRT-PCR法检测Ⅰ型胶原mRNA表达;ELISA法检测CFs细胞培养液中MMP-1的浓度。结果 加入TWEAK干预后,促进了CFs增殖,Ⅰ型胶原蛋白及P-P38MAPK蛋白表达上调,Ⅰ型胶原mRNA和MMP-1 表达上调。加入SB203580可抑制CFs增殖,部分抑制Ⅰ型胶原mRNA、Ⅰ型胶原蛋白、P-P38MAPK蛋白及MMP-1的表达。结论 TWEAK可通过P38MAPK途径促进CFs 表达Ⅰ型胶原和MMP 1。     

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。     

埃克替尼通过p38-MAPK信号通路对涎腺腺样囊性癌ACC-M细胞的凋亡诱导作用

目的：探讨埃克替尼对人涎腺腺样囊性癌细胞ACC-M凋亡的影响,阐明埃克替尼对涎腺腺样囊性癌的治疗作用机制。方法：ACC-M细胞随机分为对照组,2、4、8 μmo1/L^-1埃克替尼组,促分裂原活化蛋白激酶（APK）抑制剂SB203580(20 μmol/L^-1)组,SB203580(20 μmol/L^-1 )+埃克替尼(4 μmol/L^-1 )组。4 h后收
集细胞,采用MTT法检测各组ACC-M细胞的生长抑制率,用caspase-3活力检测试剂盒检测ACC-M细胞的凋亡情况（ 即caspase-3活力）,采用
Westernblotting法检测p-p38-MAPK蛋白的表达水平。结果：与对照组比较,埃克替尼组ACC-M细胞生长抑制率明显升高(P<0.05),caspase-3活力显著增强（P<0.05）,
p-p38-MAPK蛋白表达水平增加（P<0.05）。与4 μmol/L^-1 埃克替尼组比较,SB203580+埃克替尼组p-p38-MAPK蛋白表达水平明显降低（P<0.05）,caspase-3活力显著降低（P<0.05）。结论：埃克替尼可通过上调p-p38-MAPK信号的表达诱导ACC-M细胞凋亡。     

乳腺癌耐药性中MAPK信号转导通路与EGR-1关系的研究

目的探讨乳腺癌细胞阿霉素耐药中p38MAPK通路与EGR-1活性的关系。方法用流式细胞术、四甲基偶氮唑蓝（MTT）、RT—PCR及Western Blot等方法分别检测SB203580（15μmol／L）干预后细胞的凋亡、细胞内阿霉素浓度及细胞对阿霉素敏感性的改变;EGR-1 mRNA表达及P—gP、磷酸化p53蛋白及p38蛋白表达情况。结果经SB203580（15μmol／L）干预,流式细胞仪检测见MCF-7／Adr细胞发生显著凋亡,并呈一定时间依赖性;细胞内阿霉素浓度显著增加;MCF-7／Adr细胞对阿霉素药物的耐受性显著降低;伴随p38MAPK通路活性抑制和EGR—1mRNA表达增加,磷酸化p53蛋白表达显著上调,而P—gP蛋白显著下调。结论提示p38MAPK通路与乳腺癌细胞阿霉素耐药密切相关,p38MAPK通路调控的EGR—1激活参与乳腺癌细胞阿霉素耐药的形成。     

鞘内注射p38 MAPK抑制剂对神经病理性疼痛大鼠脊髓背角脑源性神经营养因子表达的影响

目的 观察鞘内注射p38 MAPK抑制剂SB203580对坐骨神经压缩性损伤(CCI)神经病理性疼痛大鼠的镇痛效果及脊髓背角p38丝裂原活化蛋白激酶(p38 MAPK)、脑源性神经营养因子(BDNF)的表达,探讨大鼠神经病理性疼痛可能的发生机制。 方法 30只SD雄性大鼠随机分为3组(n=10):假手术组、对照组(CCI组)、SB203580组(CCI术前30 min及术后第1~3天鞘内注射SB203580,剂量为0.1 ml/kg)。于CCI术前2 h以及术后第4~14天测定大鼠右足机械痛阈值;术后第14天取损伤侧腰段脊髓,采用免疫组化方法观察脊髓背角p38 MAPK及BDNF的表达。结果 与术前相比,假手术组术后机械痛阈值差异无统计学意义,对照组、SB203580组在CCI术后机械痛阈值明显降低(P<0.05);与假手术组相比,CCI术后,对照组、SB203580组机械痛阈值明显降低(P<0.05);与对照组相比,CCI术后第4~14天SB203580组机械痛阈值明显升高(P<0.05)。与假手术组相比,对照组、SB203580组脊髓背角p38 MAPK表达及BDNF释放明显增加(P<0.05);与对照组相比,SB203580组损伤侧脊髓背角p38 MAPK表达及BDNF释放明显降低(P<0.05)。结论 鞘内注射p38 MAPK抑制剂可能通过降低损伤侧脊髓背角p38 MAPK表达,抑制BDNF释放,从而缓解CCI大鼠慢性神经病理性疼痛。     

LXA4通过p38MAPK/Nrf2信号通路诱导H9c2心肌细胞HO-1高表达

目的:探讨脂氧素A4(lipoxin A4,LXA4)诱导心肌细胞H9c2中血红素加氧酶(heme oxygenase,HO)-1表达可能涉及的信号转导通路?方法:分别用核因子E2相关因子2(nuclear factor-E2 related factor 2,Nrf2)的抑制剂ATRA?p38MAPK的抑制剂SB203580?LXA4联合ATRA?LXA4联合SB03580预处理H9c2细胞后进行缺氧/复氧处理,RT-PCR?Western blot?免疫荧光等检测HO-1?Nrf2以及p38MAPK mRNA和蛋白表达的变化?结果:与只行缺氧/复氧处理的细胞相比,LXA4预处理的H9c2细胞HO-1 mRNA和蛋白的表达明显升高(P < 0.05),而ATRA?SB203580分别抑制了Nrf2的聚集和p38MAPK的磷酸化(P < 0.05),从而抑制了LXA4对HO-1的诱导(P < 0.05)?结论:LXA4预处理诱导心肌细胞H9c2的HO-1高表达,具有抗缺氧/复氧损伤的作用,其机制与p38MAPK/Nrf2信号通路有关?     

苦参煎与SB203580对p38MAPK信号传导通路的调控影响

目的:探讨苦参煎与SB203580对p38MAPK信号传导通路的调控影响。利用苦参煎与SB203580抑制p38 MAPK信号传导通路,来证明中药对基因转录表达具有一定的调控作用。方法:模拟血管内膜损伤术,采用ELISA方法检测188只Webster大鼠血清中P38MAPK的水平含量。将其随机平均分为正常对照组、假手术组、生理盐水组、苦参煎组和SB203580组。结果与结论:中药苦参煎有着与SB203580相同的功效,即对P38MAPK的显著抑制作用。所以对血管内皮有比较明确的保护作用,能干扰MAPK信号传导通路,既能减轻内皮损伤后的炎性细胞释放反应,也能使再生的内皮某些功能得到恢复,有利于内皮细胞结构和功能恢复,防止炎性因子对细胞的损害。     

Coronary microembolization induced myocardial contractile dysfunction and tumor necrosis factor-α mRNA expression partly inhibited by SB203580 through a p38 mitogen-activated protein kinase pathway

Background  The microemboli produced during spontaneous plaque rupture and ulceration and during coronary intervention will reduce coronary reserve and cause cardiac dysfunction. It is though that inflammation caused by the microinfarction induced by the microembolization may play an essential role. It is known that the activation of p38 mitogen-activated protein kinases (MAPK) in both infected and non-infected inflammation in myocardium may cause a contractile dysfunction. But the relation between the activation of p38 MAPK and microembolization is still unknown.

Methods  Sprague-Dawley rats were randomly divided into three groups: Sham group, coronary microembolization (CME) group and SB203580 group (n=10 per group). CME rats were produced by injection of 42 μm microspheres into the left ventricle with occlusion of the ascending aorta. SB203580, a p38 MAPK inhibitor, was injected into the femoral vein after the injection of microspheres to make the SB203580 group. Left ventricular ejection fraction (LVEF) was determined by echocardiography. The protein concentration of P38 MAPK in the myocardium was assessed by Western blotting. The relative expression of mRNA for tumor necrosis factor (TNF)-α was assessed by the technique of semi-quantitative polymerase chain reaction amplification.  

Results  LVEF was depressed at three hours up to 12 hours in the CME group. Increased p38 MAPK activity and TNF-α mRNA expression were observed in the CME group. The administration of SB203580 partly inhibited p38 MAPK activity, but did not fully depress the TNF-α expression, and partly preserved cardiac contractile function.

Conclusions  p38 MAPK is significantly activated by CME and the inhibition of p38 MAPK can partly depress the TNF-α expression and preserve cardiac contractile function.