Electroacupuncture reduces apoptotic index and inhibits p38 mitogen-activated protein kinase signaling pathway in the hippocampus of rats with cerebral ischemia/reperfusion injury

Electroacupuncture attenuates cerebral hypoxia and neuronal apoptosis induced by cerebral ischemia/reperfusion injury.To further identify the involved mechanisms,we assumed that electroacupuncture used to treat cerebral ischemia/reperfusion injury was associated with the p38 mitogen-activated protein kinase（MAPK） signaling pathway.We established rat models of cerebral ischemia/reperfusion injury using the modified Zea-Longa＇s method.At 30 minutes before model establishment,p38 MAPK blocker SB20358 was injected into the left lateral ventricles.At 1.5 hours after model establishment,electroacupuncture was administered at acupoints of Chize（LU5）,Hegu（LI4）,Zusanli（ST36）,and Sanyinjiao（SP6） for 20 minutes in the affected side.Results showed that the combination of EA and SB20358 injection significantly decreased neurologic impairment scores,but no significant differences were determined among different interventional groups.Hematoxylin-eosin staining also showed reduced brain tissue injuries.Compared with the SB20358 group,the cells were regularly arranged,the structures were complete,and the number of viable neurons was higher in the SB20358 ＋ electroacupuncture group.Terminal deoxynucleotidyl transferase（Td T）-mediated d UTP nick-end labeling assay showed a decreased apoptotic index in each group,with a significant decrease in the SB20358 ＋ electroacupuncture group.Immunohistochemistry revealed reduced phosphorylated p38 expression at 3 days in the electroacupuncture group and SB20358 ＋ electroacupuncture group compared with the ischemia/reperfusion group.There was no significant difference in phosphorylated p38 expression between the ischemia/reperfusion group and SB20358 group.These findings confirmed that the electroacupuncture effects on mitigating cerebral ischemia/reperfusion injury are possibly associated with the p38 MAPK signaling pathway.A time period of 3 days could promote the repair of ischemic cerebral nerves.

Physiological roles of mitogen-activated-protein-kinase-activated p38-regulated/activated protein kinase

Mitogen-activated protein kinases(MAPKs)are a family of proteins that constitute signaling pathways involved in processes that control gene expression,cell division, cell survival,apoptosis,metabolism,differentiation and motility.The MAPK pathways can be divided into conventional and atypical MAPK pathways.The first group converts a signal into a cellular response through a relay of three consecutive phosphorylation events exerted by MAPK kinase kinases,MAPK kinase,and MAPK.Atypical MAPK pathways are not organized into this three-tiered cascade.MAPK that belongs to both conventional and atypical MAPK pathways can phosphorylate both non-protein kinase substrates and other protein kinases.The latter are referred to as MAPK-activated protein kinases.This review focuses on one such MAPK-activated protein kinase,MAPK-activated protein kinase 5(MK5)or p38-regulated/activated protein kinase(PRAK).This protein is highly conserved throughout the animal kingdom and seems to be the target of both conventional and atypical MAPK pathways.Recent findings on the regulation of the activity and subcellular localization,bona fide interaction partners and physiological roles of MK5/PRAK are discussed.

Hippocampal activation of c-Jun N-terminal kinase,protein kinase B,and p38 mitogen-activated protein kinase in a chronic stress rat model of depression

Recent studies have shown that varied stress stimuli activate c-Jun N-terminal kinase （JNK）, protein kinase B （Akt）, and p38 mitogen-activated protein kinase （p38） signal transduction pathway, and also regulate various apoptotic cascades. JNK and p38 promote apoptosis, but Akt protects against apoptosis, in hippocampal neurons. However, changes in the transduction pathway in different regions of brain tissues in a chronic stress rat model of depression remain poorly understood. Results from this study showed that JNK phosphorylation levels were significantly greater in the stress group hippocampus compared with the control group （P 〈 0.05）. No significant difference in JNK phosphorylation levels was detected in the rat cerebral cortex between stress and control groups, and no significant difference in Akt and p38 phosphorylation levels was detected in the rat hippocampus and cerebral cortex between stress and control groups （P 〉 0.05）. These results suggested that the JNK signal pathway is activated by JNK phosphorylation and participates in pathophysiological changes in rat models of depression.

Inhibiting p38 mitogen-activated protein kinase attenuates cerebral ischemic injury in Swedish mutant amyloid precursor protein transgenic mice

Cerebral ischemia was induced using photothrombosis 1 hour after intraperitoneal injection of the p38 mitogen-activated protein kinase （MAPK） inhibitor $B239063 into Swedish mutant amyloid precursor protein （APP/SWE） transgenic and non-transgenic mice. The number of surviving neurons in the penumbra was quantified using Nissl staining, and the activity of p38 MAPKs was measured by western blotting. The number of surviving neurons in the penumbra was significantly reduced in APP/SWE transgenic mice compared with non-transgenic controls 7 days after cerebral ischemia, but the activity of p38 MAPKs was significantly elevated compared with the non-ischemic hemisphere in the APP/SWE transgenic mice. SB239063 prevented these changes. The APP/SWE mutation exacerbated ischemic brain injury, and this could be alleviated by inhibiting p38 MAPK activity.

p38 mitogen-activated protein kinase regulates type-Ⅰ vs type-Ⅱ phenotyping of human vascular endothelial cells

AIM: To identify kinases involved in phenotype regulation of vascular endothelial cells(VECs): Proproliferative G-protein signaling 5(RGS5)^(high)(typeⅠ) vs anti-proliferative RGS5^(low)(typeⅡ) VECs.METHODS: Proteomic kinase assays were performed to identify the crucial kinase involved in the phenotype regulation of human VECs using typeⅠ VECs, which promotes the proliferation of human vascular smooth muscle cells(VSMCs), and typeⅡ VECs, which suppress the proliferation of human VSMCs. The assays were performed using multiple pairs of typeⅠ and typeⅡ VECs to obtain the least number of candidates. The involvement of the candidate kinases was verified by evaluating the effects of their specific inhibitors on the phenotype regulation of human VECs as well as the expression levels of regulator of RGS5, which is the causative gene for the "typeⅡ to typeⅠ" phenotype conversion of human VECs. RESULTS: p38α mitogen-activated protein kinase(p38α MAPK) was the only kinase that showed distinctive activities between typeⅠ and typeⅡ VECs: p38α MAPK activities were low and high in type-Ⅰand typeⅡ VECs, respectively. We found that an enforced expression of RGS5 indeed lowered p38α MAPK activitiesin typeⅡ VECs. Furthermore, treatments with a p38α MAPK inhibitor nullified the anti-proliferative potential in typeⅡ VECs. Interestingly, MAPK inhibitor treatments enhanced the induction of RGS5 gene. Thus, there is a vicious cycle between "RGS5 induction" and "p38α MAPK inhibition", which can explain the unidirectional process in the stress-induced "typeⅡ to typeⅠ" conversions of human VECs. To understand the upstream signaling of RGS5, which is known as an inhibitory molecule against the G protein-coupled receptor(GPCR)-mediated signaling, we examined the effects of RGS5 overexpression on the signaling events from sphingosine-1-phosphate(S1P) to N-cadherin, because S1 P receptors belong to the GPCR family gene and N-cadherin, one of their downstream effectors, is reportedly involved in the regulation of VEC-VSMC interactions. We found that RGS5 specifically bound with S1P1. Moreover, N-cadherin localization at intercellular junctions in typeⅡ VECs was abolished by "RGS5 overexpression" and "p38α MAPK inhibition".CONCLUSION: p38α MAPK plays crucial roles in "type-Ⅰ vs type-Ⅱ" phenotype regulations of human VECs at the downstream of RGS5.

Neuroprotective mechanisms of rutin for spinal cord injury through anti-oxidation and anti-inflammation and inhibition of p38 mitogen activated protein kinase pathway

Rutin has anti-inflammatory, antioxidant, anti-viral, anti-tumor and immune regulatory effects. However, the neuroprotective effects of rutin in spinal cord injury are unknown. The p38 mitogen activated protein kinase （p38 MAPK） pathway is the most important member of the MAPK family that controls inflammation. We assumed that the mechanism of rutin in the repair of spinal cord injury is associated with the inhibition of p38 MAPK pathway. Allen’s method was used to establish a rat model of spinal cord injury. The rat model was intraperitoneally injected with rutin （30 mg/kg） for 3 days. After treatment with rutin, Basso, Beattie and Bresnahan locomotor function scores increased. Water content, tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6 levels, p38 MAPK protein expression and caspase-3 and -9 activities in T8–9 spinal cord decreased. Oxidative stress related markers superoxide dismutase and glutathione peroxidase levels increased in peripheral blood. Rutin exerts neuroprotective effect through anti-oxidation, anti-inflammation, anti-apoptosis and inhibition of p38 MAPK pathway.

Xuebijing alters tumor necrosis factor-alpha, interleukin-1beta and p38 mitogen activated protein kinase content in a rat model of cardiac arrest following cardiopulmonary resuscitation

We established a rat model of cardiac arrest by clamping the endotracheal tube of adult rats at expiration. Twenty-four hours after cardiopulmonary resuscitation, nerve cell injury and expression of tumor necrosis factor-α, interleukin-1β, and p38 mitogen activated protein kinase content were increased. Rats injected with Xuebijing, a Chinese herb compound preparation, exhibited normal cellular structure and morphology, dense neuronal cytoplasm, and decreased tumor necrosis factor-α, interleukin-1β, and p38 mitogen activated protein kinase expression at 24 hours following cardiopulmonary resuscitation. These data suggest that Xuebijing can attenuate neuronal injury induced by hypoxia and reperfusion during cardiopulmonary resuscitation.

N-methyl-D-aspartate receptor effects on p38 mitogen activated protein kinase and its role in a rat model of diabetic neuropathic pain

BACKGROUND： Activated N-methyl-D-aspartate （NMDA） receptor is involved in the formation of chronic neuropathic pain, and its antagonist, ketamine, exhibits effective amelioration of diabetic neuropathic pain （DNP）. However, the mechanisms of NMDA receptor participation in the formation and maintenance of DNP remain poorly understood. OBJECTIVE： To evaluate the role NMDA receptor plays in DNP and effects on p38 mitogen activated protein kinase （p38 MAPK） in a rat model of DNP. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Human Embryonic Stem Cell Research Institute of Yunyang Medical College Affiliated Taihe Hospital between July 2005 and September 2007. MATERIALS： Streptozotocin was provided by Sigma, USA; p38 MAPK inhibitor （SB203580） was provided by Shanghai KangChen Biotech, China; NMDA receptor antagonist （MK-801） was purchased from Shanghai Yope Biotech, China. METHODS： A total of 128 healthy, Wistar rats of clean grade, aged 3 months and weighing 180- 220 g, were randomly assigned to 4 groups： control, DNP model, p38 MAPK, and NMDA receptor. Each group contained 32 rats. DNP was established in all groups except for the control group by intraperitoneal injection of streptozocin （65 mg/kg）. Subsequently, 1 mg/kg SB203580 and 1 mg/kg MK-801 were injected once each week via intraperitoneal injection in the p38 MAPK and NMDA receptor groups, respectively. MAIN OUTCOME MEASURES： At the end of 2, 4, 6, and 8 weeks following streptozotocin injection, mechanical withdrawal threshold was measured in 8 animals from each group following von Frey filament stimulation. The rats were anesthetized and nerve conduction velocity of the left sciatic nerve was measured. Subsequently, the right sciatic nerve, the lumbar segment of the spinal cord, and dorsal root ganglia were removed from the L3-6 segment for microscopic examination, p38 MAPK expression was determined using immunohistochemistry and Western blot analysis. Expression of NMDA receptor 1 mRNA in dorsal root ganglion and spinal cord neurons was detected using RT-PCR. RESULTS： Mechanical withdrawal threshold and nerve conduction velocity were significantly reduced, and p38 MAPK and NMDA receptor 1 mRNA expression in the spinal cord and dorsal root ganglia were significantly increased, in the model, p38 MAPK, and NMDA receptor groups compared with the control group at all time points （P 〈 0.05）. At 4-8 weeks following successful DNP model establishment, SB203580 and MK-801 increased mechanical withdrawal threshold, accelerated nerve conduction velocity, and attenuated p38 MAPK expression, compared with the model group. The NMDA receptor group exhibited downregulated mRNA expression of NMDA receptor 1 compared with the model and p38 MAPK groups （P 〈 0.05）. CONCLUSION： NMDA receptor was highly expressed in the brains of DNP rats and was involved in DNP development via activation of the p38 MAPK signal pathway.

胎儿和出生后机体皮肤内p38MAPK及MAPKKs基因表达变化的比较性研究

目的 探讨p38丝裂素活化蛋白激酶(p38mitogen- activated protein kinase,p38MAPK)及其上游信号分子MAPKKs(mkk3和mkk6 )基因,在不同胎龄胎儿皮肤和出生后机体皮肤组织中表达的变化,及其可能的生物学意义。 方法 用病理学技术检测不同发育时期皮肤的结构特征后,提取18例不同胎龄(13～32周)的胎儿皮肤和6例出生后机体皮肤组织(作为对照)的总RNA,分离m RNA,用逆转录-聚合酶链反应(reverse transcription- polymerasechain reaction,RT- PCR)方法检测3种基因在不同组织中的表达规律。 结果 p38MAPK,m kk3和mkk6基因在不同发育阶段的皮肤组织中都有表达。在早期妊娠胎儿的皮肤组织中,这三种基因表达较强,随着胎儿的生长发育,皮肤组织内这三种基因表达逐渐减弱。在出生后机体的皮肤细胞中,p38MAPK、mkk3和mkk6基因的表达量分别为妊娠早期皮肤的39.6 %、6 3.5 %和5 4 .5 % ,明显减弱(P<0 .0 1)。 结论 p38MAPK、mkk3和mkk6基因在不同发育阶段人皮肤组织内都有表达,显示细胞外信号引起的p38MAPK信号通路可能对皮肤的发生、结构功能的维持以及伤后修复十分重要。在早期妊娠胎儿皮肤中p38MAPK及其上游信号分子MAPKKs基因的高表达可能是胎儿皮肤组织细胞快速增殖、皮肤创面无瘢痕愈合的机制之一。

P38MAPK在慢性阻塞性肺疾病中的作用

慢性阻塞性肺疾病是一种慢性气道炎症性疾病,是肺部对有害颗粒或气体的所产生的异常炎症反应,这种气道炎症常导致持续性的气流受限和肺功能的进行性下降。此外,由肺内炎症反应等所导致的氧化应激反应也参与了COPD的发病。p38丝裂原活化蛋白激酶（p38 mitogen-activated protein kinase,p38MAPK）是细胞内重要的信号传递者,

补肾活血方对兔NPMSCs移植治疗退变椎间盘P 38 MAPK信号通路的影响

目的探讨补肾活血方对兔髓核间充质干细胞(nucleus pulposus-derived mesenchymal stem cells,NPMSCs)移植治疗退变椎间盘P 38丝裂原活化蛋白激酶(p38 mitogen-activated protein kinase,P 38 MAPK)信号通路的影响。方法选取128只SPF级健康新西兰大白兔,其中2例用于NPMSCs的获取、纯化及培养,选取24只为假手术组(A组);兔退变椎间盘模型成功100只,模型组(B组,24只)、补肾活血方组(C组,24只)、NPMSCs移植组(D组,24只)、补肾活血方+NPMSCs移植组(E组,24只),死亡6只。每组在治疗前、治疗后1周、治疗后2周、治疗后3周4个时间点均处死6只兔,取相应椎间盘,采用酶联免疫测定每组大兔不同时间点椎间盘P 38 MAPK、基质金属蛋白酶3(matrix metalloproteinase 3,MMP-3)、基质金属蛋白酶7(matrix metalloproteinase 7,MMP-7)的表达。结果(1)各组变化趋势:A组、B组组内不同时间点P 38 MAPK、MMP-3、MMP-7蛋白相对表达差异无统计学意义(P>0.05);C组、D组、E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达与治疗前、治疗后1周、治疗后2周、治疗后3周呈下降趋势,各组组内差异有统计学意义(P<0.01)。(2)与A组比较:B组、C组、D组、E组P38MAPK、MMP-3、MMP-7蛋白相对表达在治疗前、治疗后1周、治疗后2周、治疗后3周均升高,组间差异有统计学意义(P<0.01)。(3)与B组比较:C组、D组、E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗前差异无统计学意义(P>0.05);在治疗后1周、治疗后2周、治疗后3周均降低,组间差异有统计学意义(P<0.01)。(4)与C组比较:D组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗前、治疗后1周、治疗后2周、治疗后3周时同期差异无统计学意义(P>0.05);E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗后1周、治疗后2周、治疗后3周均降低,组间差异有统计学意义(P<0.01)。(5)与D组比较:E组P 38 MAPK、MMP-3、MMP-7蛋白相对表达在治疗后1周、治疗后2周、治疗后3周均降低,组间差异有统计学意义(P<0.01)。结论补肾活血方对兔NPMSCs移植治疗退变椎间盘具有协同作用;其机制可能与抑制P 38 MAPK信号通路,下调MMP-3、MMP-7蛋白相关。

锰诱导PC12细胞凋亡与p-38MAPKs的关系

目的 以鼠嗜铬神经瘤细胞 (PC12 )为模型 ,筛选锰对神经细胞增殖抑制作用的时间及剂量 ,观察细胞形态学、细胞周期和生化指标改变与丝裂原活化蛋白激酶 (p38MAPKs)活化表达间的关系。方法 用 2 0 0 ,4 0 0 ,6 0 0 ,80 0μmol/LMnCl2 的培养液 ,分别作用对数生长期PC12细胞 1,2 ,3,4d后 ,用噻唑蓝比色 (MTT)筛选锰的细胞毒性剂量 ;流式细胞仪检测细胞周期分布 ;透射电镜观察细胞形态学变化 ;琼脂糖凝胶电泳检测MnCl2 对PC12细胞基因组DNA的影响。蛋白印迹 (western -blot)法检测 p -p38。结果 MTT实验结果显示 ,2 0 0～ 80 0 μmol/LMnCl2 作用 1,2 ,3,4d对PC12有显著的抑制作用 ,呈剂量和时间依赖趋势 ,6 0 0 μmol/LMnCl2 作用 4d对PC12的抑制率可达 5 0 %以上。流式细胞仪检测实验表明 :6 0 0 μmol/LMnCl2 作用 4d将PC12细胞周期阻滞在S期 ,诱导细胞凋亡 ,与电镜结果一致 ,同样条件下细胞DNA碎片化。Western -blot实验显示 6 0 0 μmol/LMnCl2 作用 1,2 ,3,4dp -p38逐渐升高 ,3d时较对照组增加 6 6倍 (n =3,P <0 0 5 ) ,2 0 0 ,4 0 0 ,6 0 0 μmol/LMnCl2 作用 4d时 ,磷酸化蛋白 38(p - p38)也逐渐升高 ,4 0 0 μmol/LMnCl2 作用 4d时较对照组升高 4 7倍 (n =3,P <0 0 5 )。结论 锰通过MEK3/

特异性p^(38)MAPK抑制剂SB203580对乳鼠小脑颗粒神经元的保护作用

目的 研究 p38丝裂原激活蛋白激酶 (MAPK)选择性抑制剂SB2 0 35 80对乳鼠小脑颗粒神经元凋亡的保护作用。方法 SD乳鼠小脑颗粒神经元培养 ,琼脂糖凝胶电泳 ,SAPK/JNK分析试剂盒作激酶分析。结果 PI 3 K的特异性抑制剂LY2 940 0 2诱导小脑颗粒神经元凋亡 ,但SB2 0 35 80通过抑制细胞凋亡而促进小脑颗粒神经元的存活 ,且有浓度依赖性。LY2 940 0 2诱导凋亡的颗粒神经元中c Jun的表达量和磷酸化水平均升高 ,JNK被激活。但是 ,当小脑颗粒神经元生长在含SB2 0 35 80的高钾培养基中 ,c Jun的表达量、磷酸化水平和JNK的活性都明显的降低。结论 SB2 0 35 80通过抑制JNK的活性 ,降低c Jun的表达和磷酸化水平 。

黄芪对脂多糖诱导大鼠急性肺损伤p38 MAPK表达的影响

目的探讨脂多糖(LPS)诱导急性肺损伤(ALI)大鼠肺组织磷酸化p38 MAPK表达的变化以及黄芪对其之影响。方法静脉注射LPS复制大鼠ALI模型。随机分成3组:正常对照组、ALI组和黄芪组。采用蛋白质印迹检测肺组织磷酸化p38 MAPK的表达,并观察大鼠动脉血氧分压(PaO2)、肺湿/干重比(W/D)、支气管肺泡灌洗液(BALF)白蛋白、血清TNF-α的变化以及肺组织病理学改变。结果LPS诱导大鼠ALI时肺组织磷酸化p38 MAPK的表达较正常对照组显著增加(P<0.01)。黄芪注射液可显著抑制大鼠肺组织磷酸化p38MAPK表达,降低W/D、BALF白蛋白以及血清TNF-α含量,使下降的PaO2回升,减轻肺组织病理学损伤。结论ALI时肺组织p38 MAPK磷酸化表达增加;黄芪注射液对内毒素性肺损伤有保护作用,其机制可能与抑制磷酸化p38 MAPK的表达有关。

p38α MAPK pathway:A key factor in colorectal cancer therapy and chemoresistance

Colorectal cancer(CRC)remains one of the most common malignancies in the world.Although surgical resection combined with adjuvant therapy is effective at the early stages of the disease,resistance to conventional therapies is frequently observed in advanced stages,where treatments become ineffective.Resistance to cisplatin,irinotecan and 5-fluorouracil chemotherapy has been shown to involve mitogen-activated protein kinase(MAPK)signaling and recent studies identified p38αMAPK as a mediator of resistance to various agents in CRC patients.Studies published in the last decade showed a dual role for the p38αpathway in mammals.Its role as a negative regulator of proliferation has been reported in both normal(including cardiomyocytes,hepatocytes,fibroblasts,hematopoietic and lung cells)and cancer cells(colon,prostate,breast,lung tumor cells).This function is mediated by the negative regulation of cell cycle progression and the transduction of some apoptotic stimuli.However,despite its anti-proliferative and tumor suppressor activity in some tissues,the p38αpathway may also acquire an oncogenic role involving cancer related-processes such as cell metabolism,invasion,inflammation and angiogenesis.In this review,we summarize current knowledge about the predominant role of the p38αMAPK pathway in CRC development and chemoresistance.In our view,this might help establish the therapeutic potential of the targeted manipulation of this pathway in clinical settings.

p38 MAPK inhibition alleviates experimental acute pancreatitis in mice

BACKGROUND： The mitogen-activated protein kinases （MAPKs） signaling pathway is involved in inflammatory process. However,the mechanism is not clear. The present study was to investigate the role of p38 MAPK in acute pancreatitis in mice.METHODS： Mice were divided into 4 groups： saline control; acute pancreatitis induced with repeated injections of cerulein; control plus p38 MAPK inhibitor SB203580; and acute pancreatitis plus SB203580. The pancreatic histology, pancreatic enzymes, cytokines, myeloperoxidase activity, p38 MAPK and heat shock protein （HSP） 60 and 70 were evaluated.RESULTS： Repeated injections of cerulein resulted in acute pancreatitis in mice, accompanying with the activation of p38 MAPK and overexpression of HSP60 and HSP70 in the pancreatic tissues. Treatment with SB203580 significantly inhibited the activation of p38 MAPK, and furthermore, inhibited the expression of HSP60 and HSP70 in the pancreas, the inflammatory cytokines in the serum, and myeloperoxidase activity in the lung.CONCLUSION： The p38 MAPK signaling pathway is involved in the regulation of inflammatory response and the expression of HSP60 and HSP70 in acute pancreatitis.

IL-36 Cytokine Expression and Its Relationship with p38 MAPK and NF-κB Pathways in Psoriasis Vulgaris Skin Lesions

Summary： This study examined the correlation of the expression of interleukin-36 （IL-36）, a novel member of interleukin-1 （IL-1） family, with p38 mitogen-activated protein kinase （p38 MAPK） and nu clear factor-kappa B （NF-kB） pathways in psoriasis vulgaris skin lesions. The expression levels of IL-36a, IL-3613, IL-367, phosphorylated p38 MAPK, and NF-id3p65 were detected in the skin tissues of 38 psoriasis patients and 17 healthy control subjects by real-time quantitative reverse transcription po lymerase chain reaction （qRT-PCR） and Western blotting. The cytokine expression levels were com pared between the psoriasis group and the control group. A correlation analysis between cytokine pro teins was performed in the psoriasis group. Results showed that the expression levels of IL-36a, IL-3613, IL-36y, phosphorylated p38 MAPK and NF-rh3p65 in the psoriasis group were Significantly higher than those in the control group （P〈0.001）. In the psoriasis group, the IL-36 cytokine expression was positively correlated with phosphorylated p38 MAPK and NF-kBp65 expression （P〈0.05）. A significant positive correlation was also found between the phosphorylated p38 MAPK and NF-v,.Bp65 expression （P〈0.01）. It was concluded that the increased IL-36 expression is correlated with p38 MAPK and NF-kB pathways in psoriasis vulgaris skin lesions. All the three factors may be jointly involved in the pathogenesis and local inflammatory response of psoriasis.

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 RToPCR 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.

Downregulation of p38 MAPK Involved in Inhibition of LDL-induced Proliferation of Mesangial Cells and Matrix by Curcumin

Curcumin, as a main pharmacological component in the traditional Chinese medicine-- tttrmeric, has shown anti-inflammatory, anti-oxidation, anti-tumor and anti-fibrotic effects. This study aimed to investigate the possible underlying signaling pathway which was involved in the inhibition of LDL-induced proliferation of mesangial cells and matrix by curcumin. Rat mesangial cells in vitro were incubated with low-density lipoprotein （LDL） and different concentrations of curcumin （0, 6.25, 12.5, 25.0 9mol/L） or p38 MAPK inhibitor, SB203580 （10 μmol/L）. Under LDL incubation, mesangial cells proliferated, the expression of MMP-2 mRNA and protein was decreased, the expression of COX-2 mRNA and protein was increased, reactive oxygen species （ROS） generation was increased and p38 MAPK was activated significantly （P〈0.05）. When LDL-induced cells were treated with curcumin in the concentration of 12.5 or 25.0 μmol/L, LDL-induced proliferation ofmesangial cells was suppressed, the expression of MMP-2 mRNA and protein increased, the expression of COX-2 mRNA and protein downregulated, the production of ROS inhibited and p38 MAPK inactivated （P〈0.05）. In conclusion, curcumin can inhibit the LDL-induced proliferation of mesangial cells and up-regulate the expression of MMP-2, which may be related with the inhibitory effect of curcumin on COX-2 expression, ROS pro- duction and p38 MAPK.

The Cross-talk between ROS and p38MAPKα in the Ex Vivo Expanded Human Umbilical Cord Blood CD133^+ Cells

This study investigated the correlation between and compared the effects of reactive oxygen species（ROS） and p38 mitogen-activated protein kinase α（p38MAPKα） in the ex vivo expanded umbilical cord blood（hUCB） CD133＋ cells.hUCB CD133＋ cells were cultured in the hematopoietic stem cells（HSCs） culture medium with N-acetylcysteine（NAC,an anti-oxidant）,p38MAPKα-specific inhibitor（SB203580） or their combination.The levels of ROS and expression of phosphorylated p38MAPKα（p-p38） in CD133＋ cells were flow cytometrically detected.The efficacy of ex vivo expansion was evaluated by the density of CD133＋ cell sub-group colony-forming cells（CFC） and cobblestone area-forming cells（CAFC） assay.Our results showed decreased ROS levels in NAC,SB203580,and their combination treatment groups were almost 37%,48%,and 85%,respectively.Furthermore,SB203580 abrogated the activation of p38MAPKα more obviously than NAC.Moreover,the CD133＋ cells in SB203580 treatment group had a 21.93±1.36-fold increase,and 14.50±1.19-fold increase in NAC treatment group,but only 10.13±0.57-fold increase in control group.In addition,SB203580 treatment led a higher level increase in the number of CFU and CAFC than NAC did.These findings suggested that,in expanded CD133＋ cells,ROS activates p38MAPKα,which,in turn,induces ROS production,and p38MAPKα might be the most suitable regulator in ROS-p38MAPKα pathway for the promotion of HSCs ex vivo expansion.