DATS通过p38MAPK通路抑制LPS诱导的小鼠MH-S细胞TNF-α及IL-1β表达

目的探讨p38MAPK在二烯丙基三硫(DATS)抑制脂多糖(LPS)诱导小鼠肺泡巨噬细胞促炎细胞因子表达中的作用。方法体外培养MH-S细胞,用DATS和(或)LPS进行干预,Western blot检测细胞p38及磷酸化p38(p-p38)的表达;用LPS和(或)SB203580孵育细胞,反转录PCR检测细胞中TNF-α、IL-1βmRNA表达,Western blot检测细胞磷酸化(p-IκB)及非磷酸化IκB的表达。结果 LPS刺激MH-S细胞可导致p-p38表达增加,呈时间依赖性;用DATS(0.1、0.5、2.5、5.0 mg.L-1)预处理细胞30 min后再给予LPS刺激,p-p38表达呈剂量依赖性下降;单独DATS对p-p38表达无明显影响。p38特异性抑制剂SB203580可剂量依赖性地抑制LPS诱导的p-IκB蛋白、TNF-α及IL-1βmR-NA表达。结论 DATS可通过抑制p38MAPK通路抑制IκB磷酸化及NF-κB活化,进而下调LPS诱导小鼠肺泡巨噬细胞TNF-α、IL-1βmRNA表达。     

八肽胆囊收缩素通过p38MAPK通路抑制LPS诱导的RAW264.7细胞IL-1β表达

目的研究八肽胆囊收缩素(CCK-8)对LPS诱导RAW264.7细胞IL-1β表达的影响及相关机制。方法用ELISA及RT-PCR法检测RAW264.7细胞IL-1βmRNA及蛋白表达;用Western blot检测RAW264.7细胞p38 MAPK的磷酸化水平。结果①LPS可时间依赖性的诱导RAW264.7细胞IL-1βmRNA及蛋白的表达,分别于刺激后3 h及6 h达到高峰;②10-10 mol.L-1 CCK-8对LPS诱导的RAW264.7细胞IL-1β表达无影响;10-8、10-6 mol.L-1CCK-8浓度依赖性地抑制了LPS诱导的RAW264.7细胞IL-1β表达;③10-10 mol.L-1 CCK-8未影响LPS诱导的p-p38MAPK水平,10-8、10-6 mol.L-1 CCK-8浓度依赖性地抑制了LPS诱导的p-p38 MAPK水平;④p38 MAPK特异性抑制剂SB203580可抑制LPS诱导的RAW264.7细胞IL-1β表达,与CCK-8共同作用后,抑制作用进一步加强。结论 CCK-8通过抑制p38 MAPK磷酸化而抑制了LPS诱导的RAW264.7细胞IL-1β表达,这可能是CCK-8发挥抗炎作用的信号转导机制之一。     

阿司匹林抑制脂多糖诱导RAW264.7细胞MMP-9表达及机制研究

目的:探讨阿司匹林对脂多糖(LPS)诱导RAW264.7细胞中基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)的表达及其机制研究.方法:MTT法检测LPS诱导RAW264.7细胞作用下,阿司匹林对细胞毒性的影响.Q-RT-PCR检测MMP-9 mRNA表达,免疫蛋白印迹法(western blot)检测MMP-9、p38 MAPK及磷酸化p38(Phospho-p38,P-p38)蛋白表达.特异性抑制剂SB203580(SB)阻断p38MAPK通路后,分别应用Q-RT-PCR和Western blot检测MMP-9的基因和蛋白表达.结果:阿司匹林呈剂量依赖性抑制MMP-9基因和蛋白表达.与LPS组相比,阿司匹林可明显抑制P-p38MAPK蛋白的表达,而p38MAPK总蛋白无明显变化.抑制p38MAPK通路后,MMP-9 mRNA和蛋白水平均明显下调.结论:阿司匹林抑制LPS诱导RAW264.7细胞中MMP-9表达可能与抑制p38MAPK信号转导通路有关,进而发挥其抗AS药理作用.     

TLR4-p38MAPK信号通路在金黄色葡萄球菌感染人巨噬细胞系U937过程中的表达及意义

目的观察金黄色葡萄球菌感染人巨噬细胞系U937细胞后信号通路Toll样受体4(TLR4)-p38蛋白激酶(p38MAPK)的表达及意义。方法体外培养人巨噬细胞系U937细胞,感染0、30、60和90 min时收集细胞,应用Western blot法检测各组TLR4和p38MAPK蛋白表达的变化;在另一实验中,分为对照组、金黄色葡萄球菌感染60 min组及p38MAPK抑制剂SB203580 5 mg/m L干预组、SB203580 10 mg/m L干预组,应用Western blot法检测各组TLR4和p38MAPK蛋白表达的变化。结果随着感染时间的延长,TLR4和p38MAPK蛋白的表达逐渐增加;给予SB203580抑制剂后,TLR4和p38MAPK蛋白的表达明显减弱。结论金黄色葡萄球菌感染U937细胞可引起TLR4-p38MAPK信号通路的活化,而SB203580对其有明显的抑制作用,证明TLR4-p38MAPK信号通路与金黄色葡萄球菌感染U937细胞密切相关。     

丝裂原活化蛋白激酶抑制剂对急性肺损伤影响

目的探讨p38MAPK抑制剂SB203580对大鼠急性肺损伤影响。方法采用LPS建立SD大鼠急性肺损伤模型，随机分为对照组、LPS组、SB203580组。造模后注射p38MAPK抑制剂SB203580，在1h、3h、6h及12h时，剖杀大鼠，观察肺组织病理改变，ELISA法测血清中的TNF—α及IL-6；免疫组化检测肺组织中的p38MAPK及其磷酸化-p38MAPK。结果注射LPS后，SB203580治疗组较LPS组血清中的TNF—α及IL-6显著减少（P〈0．05 or 0.01）；肺组织中的磷酸化-p38MAPK的表达显著减轻，而p38丝裂原活化蛋白激酶未明显减轻。结论p38MAPK抑制剂SB203580可减轻血清中的TNF-α及IL-6和肺组织中的磷酸化-p38MAPK的表达，从而减轻LPS诱导的急性肺损伤。     

p38MAPK对内毒素致大鼠急性肺损伤的保护

目的 研究p38丝裂原活化蛋白激酶(p38MAPK)在内毒素引起急性肺损伤中的作用.方法 60只SD大鼠随机分生理盐水(NS)组、内毒素(LPS)组、SB203580+LPS(SB+LPS)组和SB203580+NS(SB+NS)组.ELISA法检测不同时间点大鼠支气管肺泡灌洗液(BALF)中肿瘤坏死因子(TNF)-α和白细胞介素(IL)-6浓度,HE染色检测肺组织病理学变化,Western blot法检测肺组织中磷酸化p38MAPK、核因子-kB(NF-kB)、p65和NF-kB抑制蛋白(IkBa)的表达.结果 LPS组大鼠BALF中TNF-α、IL-6的浓度明显升高(P＜0.05),肺组织破坏明显.磷酸化p38MAPK及胞核中NF-αB 065表达显著增多,胞浆中IkBa表达显著减少.SB+LPS组肺组织损伤程度轻,BALF中TNF-α、IL-6的释放显著受抑(P＜0.01),肺组织NF-kB活化及胞浆中IkBα鼬的降解均明显受抑(P＜0.01).结论 p38MAPK在LPS诱导的急性肺损伤中发挥重要作用,p38MAPK可能参与NF-kB的活化过程.     

MCI-186对β-淀粉样肽诱导SH-SY5Y细胞凋亡及p38MAPK蛋白表达的影响

目的研究依达拉奉(MCI-186)对阿尔茨海默病(AD)细胞损伤的保护作用及其机制。方法将人神经母细胞瘤SH-SY5Y细胞分为五组:空白对照组、溶剂对照组、β淀粉样肽(Aβ)组、Aβ+溶剂对照组和Aβ+药物处理组。用Aβ25-35处理SH-SY5Y细胞,建立AD细胞模型。采用DAPI荧光染色法计数凋亡细胞,Western blot法检测磷酸化的p38丝裂原活化蛋白激酶(p-p38MAPK)表达。结果 Aβ25-35引起时间和剂量依赖性的SH-SY5Y细胞凋亡,并使p-p38MAPK表达增加(P<0.05)。MCI-186与p38MAPK抑制剂SB239063均抑制Aβ25-35诱导的SH-SY5Y细胞凋亡及p-p38MAPK表达(P<0.05)。结论 MCI-186通过抑制p38MAPK磷酸化,对Aβ25-35诱导的SH-SY5Y细胞凋亡起到保护作用。     

P-选择素对黑色素瘤细胞整合素β_1表达的影响

目的：研究P-选择素对黑色素瘤细胞整合素β1表达的影响,探讨P-选择素在肿瘤转移中的作用。方法：培养黑色素瘤细胞B16F10,在加或不加p38丝裂原活化蛋白激酶（MAPK）抑制剂SB203580的情况下,用P-选择素蛋白进行刺激,用蛋白质印迹（Western Blot）检测刺激后B16F10细胞整合素β1蛋白表达及p38 MAPK信号分子磷酸化水平的改变,用MTT法检测黏附细胞数目的变化。结果：P-选择素刺激B16F10细胞导致p38 MAPK磷酸化水平增高,整合素β1表达上调,用特异性阻断剂阻断p38 MAPK活化可以抑制P-选择素的诱导作用。MTT检测结果显示P-选择素刺激可增加细胞与整合素β1配基纤维粘连蛋白的黏附能力,说明细胞整合素β1表达增高。结论：P-选择素可以通过激活p38 MAPK途径诱导黑色素瘤B16F10细胞整合素β1的表达,提高肿瘤细胞的黏附能力,这可能是其促进肿瘤转移的机制之一。     

CCK-8对LPS诱导小鼠骨髓来源树突状细胞分泌IL-12的影响

目的探讨八肽胆囊收缩素(cholecystokinin-octopep-tide,CCK-8)对脂多糖(lipopolysaccharide,LPS)诱导小鼠骨髓来源的树突状细胞(bone marrow-derived dendritic cell,BM-DC)分泌IL-12的影响。方法应用免疫荧光技术观察BM-DC表面CCK受体表达情况,酶联免疫吸附(ELISA)方法检测CCK-8对LPS诱导BM-DC分泌IL-12的影响,Western blot技术检测CCK-8对LPS诱导BM-DC细胞p38MAPK磷酸化的影响。结果BM-DC表面存在CCK-1R和CCK-2R;CCK-8促进LPS对BM-DC表达IL-12的诱导作用呈剂量依赖性(10-10、10-8、10-6mol·L-1);并能增加其p38磷酸化水平;CCK的1、2受体拮抗剂CR1409或CR2945均可减弱CCK-8的此种效应。结论CCK-8剂量依赖性促进了LPS诱导BM-DC分泌的IL-12,该作用由CCK-1R和CCK-2R介导,可能是通过促进p38MAPK的磷酸化作用而实现的。     

IL-17与TNF-α对HaCaT细胞IL-17R、p-p38 MAPK和炎症因子表达的共影响作用

目的 考察IL-17与TNF-α共作用对皮肤角质形成细胞系HaCaT细胞IL-17R、p-p38 MAPK表达的影响,及其对HaCaT细胞分泌IL-6、IL-8、MIP-3α等炎症因子的影响。方法 采用RT-PCR方法检测IL-17与TNF-α共作用对皮肤角质形成细胞IL-17R mRNA表达的影响;采用western blot方法检测IL-17与TNF-α共作用对HaCaT细胞表达p-p38 MAPK的影响;采用ELISA法检测IL-17与TNF-a共作用对HaCaT细胞分泌炎症因子IL-6、IL-8及MIP-3α的影响。结果 IL-17与TNF-α共作用可上调HaCaT细胞表达IL-17R和p-p38 MAPK,以及上调HaCaT细胞IL-6、IL-8、MIP-3α等炎症因子的分泌。结论 IL-17与TNF-α共作用可通过上调皮肤角质形成细胞IL-17R的表达,促进p38 MAPK的磷酸化过程而具有明显致炎作用。     

MAPK/ERK通过诱导纤维蛋白A磷酸化抑制垂体瘤细胞增殖、凋亡、迁移及相关信号转导

目的 探讨MAPK/ERK对垂体瘤细胞增殖、凋亡、迁移及相关信号转导的影响.方法 通过CCK-8法确定SB203580(MAPK/ERK抑制剂)的最佳安全浓度,然后将体外培养的垂体瘤细胞分为SB203580组和对照组,通过CCK-8法检测垂体瘤细胞的增殖情况,流式细胞术检测垂体瘤细胞的细胞凋亡百分数,RT-PCR和We...     

Inflammation in methotrexate-induced pulmonary toxicity occurs via the p38 MAPK pathway

Methotrexate (MTX) has been widely used for the treatment of inflammatory diseases and rheumatoid arthritis (RA), as well as a variety of tumors. However, MTX-induced toxicity is a serious and unpredictable side effect of this therapy and an important clinical problem. We used microarray analysis to examine MTX-induced gene expression in a human lung epithelial cell line (BEAS-2B) and identified 10 differentially expressed genes related to the p38 mitogen-activated protein kinase (MAPK) pathway, including IL-1β, MKK6, and MAPKAPK2. Differential gene expression was confirmed via real-time RT-PCR. To determine the functional significance of MTX-induced p38 MAPK activation, we used a p38 MAPK inhibitor (SB203580) to block the p38 MAPK cascade. We also used protein array technology to investigate the modulated expression of pro- and anti-inflammatory cytokines in BEAS-2B cells. MTX activated IL-1β expression and induced the phosphorylation of various proteins in the p38 MAPK cascade, including TAK1, MKK3/MKK6, p38 MAPK, MAPKAPK2, and HSP27. Finally, HSP27 activation may increase IL-8 secretion, resulting in a pulmonary inflammatory response such as pneumonitis. Although IL-1β and IL-8 expression increased, the expression of IL-4, IL-6, IL-12, TNF-α, MIP-1α, and MIP-1β decreased in a dose-dependent manner. These results suggest that the modulation of cytokine expression may play an important role in MTX-induced pulmonary toxicity.     

Polygalasaponin F inhibits secretion of inflammatory cytokines via NF-κB pathway regulation

To study the anti-neuroinflammatory mechanisms of polygalasaponin F (PS-F), ELISA method was used to detect the secretion of inflammatory cytokines. Western blot was used to detect the protein expression and phosphorylation levels. Immunofluorescence assay was used to observe the NF-κB nuclear translocation. PS-F could inhibit the release of inflammatory cytokines TNF-α and NO induced by lipopolysaccharides (LPS) and reduce the expression of inducible nitric oxide synthases (iNOS). As for MAPK-signaling pathway, PS-F could only inhibit the phosphorylation levels of p38 MAPK, but did not significantly affect the phosphorylation levels of JNK and ERK1/2 protein kinases. PS-F could inhibit NF-κB nuclear translocation in a dose-dependent manner. The results of Western blot assay were consistent with immunofluorescence assays. Meanwhile, p38-specific inhibitor SB203580 (20 μM) and p65-specific inhibitor PDTC (100 μM) were, respectively, administered as a positive control. In addition, PS-F could significantly inhibit the cytotoxicity of conditioned medium prepared by LPS-stimulated BV-2 microglia (LPS conditioned media) to neuronal PC12 cells and improve cell viability. PS-F inhibits the secretions of neuroinflammatory cytokines by the regulation of NF-κB-signaling pathway.     

Role of mitogen-activated protein kinase family in serum-induced leukaemia inhibitory factor and interleukin-6 secretion by bone marrow stromal cells

1: In the haematopoietic microenvironment, bone marrow stromal cells play an important role in regulating haematopoiesis by expressing various cytokines, including leukaemia inhibitory factor (LIF) and interleukin-6 (IL-6). However, the intracellular signal that regulates cytokine secretion in bone marrow stromal cells has not been determined. The aim of this study was to evaluate the role of mitogen-activated protein kinase (MAPK) family in serum-induced secretion of LIF and IL-6 by bone marrow stromal cells. 2: Transformed human bone marrow stromal cells (HS-5) were stimulated with foetal calf serum (FCS) to produce LIF and IL-6. FCS also induced activation of extracellular signal-regulated kinase (ERK), p38 MAPK and c-Jun NH(2)-terminal kinase (JNK). 3: Both PD98059 (MAPK/ERK kinase inhibitor) and SB203580 (p38 MAPK inhibitor) attenuated FCS-induced LIF protein production and gene expression. SB203580 decreased IL-6 production and gene expression, but PD98059 had no effect on IL-6 production and gene expression. 4: Expression of a dominant-negative mutant form of JNK1 that blocked FCS-induced JNK activity had no effect on protein production and gene expression of these cytokines. 5: These findings demonstrate that both ERK and p38 MAPK are involved in FCS-induced LIF secretion, whereas only p38 MAPK is important for IL-6 secretion, and that FCS-induced activation of JNK has no effect on the production of LIF and IL-6. We conclude that, in spite of their similar biological effects, they are differentially regulated at the level of MAPK activity in bone marrow stromal cells.     

Cytokine regulation by MAPK activated kinase 2 in keratinocytes exposed to sulfur mustard

Uncontrolled inflammation contributes to cutaneous damage following exposure to the warfare agent bis(2-chloroethyl) sulfide (sulfur mustard, SM). Activation of the p38 mitogen activated protein kinase (MAPK) precedes SM-induced cytokine secretion in normal human epidermal keratinocytes (NHEKs). This study examined the role of p38-regulated MAPK activated kinase 2 (MK2) during this process. Time course analysis studies using NHEK cells exposed to 200 μM SM demonstrated rapid MK2 activation via phosphorylation that occurred within 15 min. p38 activation was necessary for MK2 phosphorylation as determined by studies using the p38 inhibitor SB203580. To compare the role of p38 and MK2 during SM-induced cytokine secretion, small interfering RNA (siRNA) targeting these proteins was utilized. TNF-α, IL-1β, IL-6 and IL-8 secretion was evaluated 24 h postexposure, while mRNA changes were quantified after 8 h. TNF-α, IL-6 and IL-8 up regulation at the protein and mRNA level was observed following SM exposure. IL-1β secretion was also elevated despite unchanged mRNA levels. p38 knockdown reduced SM-induced secretion of all the cytokines examined, whereas significant reduction in SM-induced cytokine secretion was only observed with TNF-α and IL-6 following MK2 knockdown. Our observations demonstrate potential activation of other p38 targets in addition to MK2 during SM-induced cytokine secretion.     

p38蛋白激酶抑制剂SB203580对支气管哮喘小鼠气道炎症和Th2类细胞因子的影响

目的观察特异性p38蛋白激酶(p38 MAPK)抑制剂SB203580对哮喘小鼠气道炎症和Th2类细胞因子的影响。方法BALB/c小鼠30只随机分成3组,即正常对照组、哮喘模型组和SB203580干预组。通过原位分子杂交和酶联免疫吸附法(ELISA)检测肺组织IL-4、IL-5 mRNA和支气管肺泡灌洗液(BALF)中白细胞介素(IL-4、IL-5)含量的变化,并观察BALF中炎症细胞和肺组织病理学改变。结果哮喘模型组小鼠BALF中炎症细胞计数和IL-4、IL-5含量以及肺组织IL-4、IL-5mRNA的表达较正常对照组明显升高,差异具有显著性(P<0.01);SB203580干预组小鼠上述指标较哮喘模型组小鼠明显降低,差异亦具有显著性(P<0.01),肺组织病理学改变明显减轻。结论SB203580能降低气道炎症细胞的聚集和炎症介质的表达。抑制p38 MAPK的活性可能成为哮喘治疗的新途径。     

Blockade of p38 mitogen-activated protein kinase pathway ameliorates delayed gastric emptying in streptozotocin-induced diabetic rats

Background and aimGastrointestinal dysfunction is one of the major complications of diabetes. The roles of inflammation in diabetes and its associated complications are increasingly recognized. p38 mitogen-activated protein kinase (MAPK) has been shown to be involved in the production of pro-inflammatory mediators. The aims of this study were to investigate the effects of SB203580, a specific p38 MAPK inhibitor, on delayed gastric emptying in diabetic rats and to elucidate its possible mechanism.MethodsSB203580 was administered in diabetic rats induced by intraperitoneal injection of streptozotocin. The gastric emptying rate of rats was measured by using phenol red solution, and blood glucose levels and body weights were observed. p38 MAPK activity and iNOS expression were assessed by Western blot analysis. The expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1β were determined by enzyme-linked immunosorbent assay.ResultsGastric emptying was delayed significantly in diabetic rats and improved significantly with SB203580; high glucose significantly activated p38 MAPK and increased the expression of iNOS, TNF-α and IL-1β. The administration of SB203580 led to a significant decrease in the activation of p38 MAPK and the expression of iNOS, TNF-α and IL-1β.ConclusionsInflammation was associated with the development of delayed gastric emptying, and blockade of p38 MAPK pathway with SB203580 ameliorates delayed gastric emptying in diabetic rats, at least in part, by inhibiting the expression of iNOS, TNF-a and IL-1β. Therefore, p38MAPK may serve as a novel target for the therapy of diabetes-related gastrointestinal dysmotility.