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。     

Role of GABAB receptors and p38MAPK/NF-κB pathway in paclitaxel-induced apoptosis of hippocampal neurons

Context: The effects of the anticancer drug paclitaxel on learning and memory are rarely studied.

Objective: This study investigated changes in GABA_B receptor expression during paclitaxel-induced apoptosis of hippocampal neurons and the role of the p38MAPK/NF-κB pathway in this process.

Materials and methods: Hippocampal neurons isolated from neonatal Sprague–Dawley rats were divided into six groups: Control (C), SB (10?µL of 10-µmol/L SB203580), SN (53?µg/mL SN50), N (1?µmol/L paclitaxel), SB?+?N (10?µmol/L SB203580?+?1?µmol/L paclitaxel) and SN?+?N (53?µg/mL SN50?+?1?µmol/L paclitaxel). Cells in different groups were treated with corresponding agents for 24?h at 37?°C. The apoptosis rate and protein levels of GABA_B1 receptors and NF-κB p65 were evaluated. Rat models of neuropathic pain was induced by paclitaxel and were divided into four groups such as N, B?+?N, SN?+?N and SN?+?B?+?N groups. Rats in the N group received intrathecal injections of normal saline solution. Rats in the B?+?N group received intrathecal injections of 10?μL baclofen (0.05?μg/μL). Rats in the SN?+?N and SN?+?B?+?N groups received intrathecal injections of SN50 and SN50 plus baclofen, respectively. Spatial learning and memory were evaluated in rat models based on the escape latency and the number of crossings over the platform and protein levels of GABA_B1 receptors, NF-κB, IL-1β and TNFα were measured by immunohistochemistry assay and western blot.

Results: The neuronal apoptosis rate was significantly increased in N (49.16?±?3.12)%, SB?+?N (31.18?±?3.02)% and SN?+?N (28.47?±?3.75)% groups, accompanied by increased levels of GABA_B1 receptors and NF-κB p65 (p?p?B1:9.0?±?1.6, NF-κB p65:29.6?±?2.4, IL-1β: 30.4?±?3.4, TNFα: 31.0?±?3.4), B?+?N, SN?+?N and SN?+?B?+?N groups evidently increased levels of GABA_B1 receptor (B?+?N:SN?+?N:SN?+?B?+?N?=?19.4?±?2.1:20.8?±?1.9:28.0?±?1.9) but significantly decreased levels of NF-κB p65 (B?+?N:SN?+?N:SN?+?B?+?N?=?21.2?±?1.5:18.6?±?2.1:12.6?±?1.5), IL-1β (B?+?N:SN?+?N:SN?+?B?+?N?=?22.0?±?1.0:19.6?±?1.8:14.6?±?1.5) and TNF α (B?+?N:SN?+?N:SN?+?B?+?N?=?23.0?±?1.6:22.2?±?0.8:16.6?±?1.7). Similar findings were found in western blot analysis.

Discussions and conclusions: Paclitaxel may reduce cognitive function in rats through the p38MAPK/NF-κB pathway and GABA_B1 receptors.     

Inhibition of p38 MAPK activation protects cardiac mitochondria from ischemia/reperfusion injury

Abstract

Context: Cardiac cell death and fatal arrhythmias during myocardial ischemia/reperfusion (I/R) can be reduced by p38 MAPK inhibition. However, the effects of p38 MAPK inhibition on cardiac mitochondria have not been investigated.

Objective: We tested the hypothesis that p38 MAPK inhibition at different times during I/R protects cardiac mitochondrial functions.

Materials and methods: Adult Wistar rats were subjected to 30?min of left anterior descending coronary artery (LAD) occlusion, followed by 120?min of reperfusion. A 2?mg/kg bolus infusion of p38 MAPK inhibitor, SB203580, was given before or during ischemia, or at reperfusion. Mitochondrial function and ultrastructure were assessed and Western blots were performed.

Results: Administration of SB203580 at any time point of I/R significantly attenuated the mitochondrial ultrastructure change, mitochondrial swelling, by increasing the absorbance at 540?nm (I/R control 0.42?±?0.03; pretreatment 0.58?±?0.04; during ischemia 0.49?±?0.02; at reperfusion 0.51?±?0.02, p?<?0.05), similar to reactive oxygen species (ROS) generation (I/R control 1300?±?48; pretreatment 1150?±?30; during ischemia 1000?±?50; at reperfusion 1050?±?55, p?<?0.05). Only SB203580 given before or during ischemia attenuated mitochondrial membrane depolarization (I/R control 0.78?±?0.04; pretreatment 1.02?±?0.03; during ischemia 1.05?±?0.12, p?<?0.05). In addition, pre-treatment of SB203580 significantly reduced the phosphorylation of p53, CREB, Bax, cytochrome c, and cleaved caspase 3.

Discussion and conclusion: The results from this study showed for the first time that p38 MAPK inhibition protects mitochondria from I/R injury.     

槐定碱对LPS诱导的RAW264.7巨噬细胞p38、iNOS表达的影响

目的探讨槐定碱(sophoridine,SRI)在内毒素导致的炎症反应中的作用。方法采用LPS诱导的RAW264.7巨噬细胞建立细胞炎症反应模型,实验细胞分为5组(n=6):空白对照组、LPS组、槐定碱组、SB203580组、SB203580+槐定碱组,利用反转录聚合酶链反应(RT-PCR)技术检测RAW264.7巨噬细胞p38 mRNA表达量;利用Western blot技术检测RAW264.7巨噬细胞p-p38与iNOS蛋白的表达量。结果槐定碱组与LPS组比较p-p38蛋白表达量和p38 mRNA表达量降低,但高于空白对照组(P<0.01),表明槐定碱可以抑制LPS诱导的RAW264.7巨噬细胞p-p38蛋白表达和p38 mRNA表达量;与LPS组比较,槐定碱组iNOS蛋白表达量降低,但高于空白对照组(P<0.01),SB203580+槐定碱组iNOS蛋白表达量低于槐定碱组和SB203580组(P<0.01),表明槐定碱可以抑制LPS诱导的RAW264.7巨噬细胞P38MAPK信号通路下游iNOS蛋白表达,并且与SB203580有协同作用。结论槐定碱可以通过抑制p38MAPK位点而下调p-p38、iNOS蛋白表达而发挥抗炎作用。     

N-乙酰半胱氨酸影响p38有丝分裂原活化蛋白激酶对顺铂诱导急性肾损伤的保护作用

目的研究N-乙酰半胱氨酸(N-acetylcysteine,NAC)对顺铂(cisplatin,CDDP)诱导大鼠急性肾损伤(acute kidney in-jury,AKI)后组织细胞凋亡的影响和与p38有丝分裂原活化蛋白激酶(p38 mitogen activated protein kinase,p38MAPK)的关系。方法静脉注射CDDP制备大鼠AKI模型。大鼠随机分为正常对照组、AKI模型对照组、NAC低剂量组(50 mg.kg-1)、NAC中剂量组(100 mg.kg-1)、NAC高剂量组(200 mg.kg-1)、特异性p38MAPK抑制剂SB203580组(10mg.kg-1)。大鼠预先连续给药3 d,给予CDDP,再继续给药5 d。TUNEL法进行细胞凋亡检查。试剂盒测定肾脏组织caspase-3。Western blot测定caspase-3、Bax、Bcl-2、磷酸化p38MAPK(phosphorylated p38MAPK,p-p38MAPK)表达。结果与正常对照组相比,CDDP诱导AKI模型组肾组织凋亡细胞增加,caspase-3、Bax、p-p38MAPK表达升高,Bcl-2表达降低(P<0.01)。与AKI模型组相比,NAC与SB203580减少凋亡细胞、降低肾脏组织caspase-3、Bax、p-p38MAPK表达和增加Bcl-2表达(P<0.01)。结论 NAC可有效防治CD-DP诱导大鼠AKI,并与p38MAPK相关。     

Effects of sivelestat treatment on acute lung injury in paraquat-intoxicated rats

Abstract

Lung injury is the main cause of death in acute paraquat (PQ) intoxication. Sivelestat (SV), a neutrophil elastase inhibitor, is effective in reducing inflammation in acute lung injury. The aim of this study was to examine the effect of SV on acute lung injury in PQ-intoxicated rats. Seven-week-old male Sprague-Dawley rats were randomly assigned to four groups: (1) control group (group N; n?=?5); (2) PQ?+?normal saline (group P; n?=?6); (3) normal saline?+?SV (group S; n?=?6) and (4) PQ?+?SV (group PS; n?=?6). SV treatment (intraperitoneally [i.p.], 20?mg/kg) was performed 30 minutes after PQ injection (i.p., 100?mg/kg), and injections were continued every hour for a total of five doses. One hour after the last treatment, blood samples were obtained for analysis of interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α). Lung sections were stained with hematoxylin--eosin for light microscopic analysis. Neutrophil infiltration score of group PS was significantly lower than that of group P (p?<?0.05). But, other scores and total score had no significant differences. IL-6 of group PS did not differ, compared to group P. In addition, there were no differences among the four groups. TNF-α of group PS was reduced, in comparison to the level of group P. SV attenuated neutrophil infiltration in PQ-induced acute lung injury in rats. In addition, systemic inflammation was partially suppressed with SV treatment, suppressing TNF-α production. These results suggest that SV reduces paraquat-induced lung injury, at least partially, by inhibiting neutrophil infiltration and TNF-α secretion.     

黄芪多糖在未成年大鼠心肌缺血再灌注炎性损伤中的作用

目的：研究黄芪多糖在未成年大鼠心肌缺血再灌注炎性损伤中的作用。方法：1周龄雄性SD大鼠随机分为5组,假手术组（S组）、缺血再灌注组（I/R组）、黄芪多糖组（40 mg·kg^-1,APS组、p38MAPK阻断剂SB203580组（5 mg·kg^-1,SB组）,APS+SB203580组（APS 40 mg·kg^-1+SB203580 5 mg·kg^-1,APS+SB组） ,给药20 d后,进行冠状动脉左前降支结扎60 min后恢复血流再灌注120 min,经眼眶采血后处死大鼠。ELISA法和Western-blot法分别测定外周血和心肌组织中TNF-α、NF-κB、p38MAPK及p-p38MAPK蛋白表达。结果：在外周血和心肌组织中,与S组比较,I/R组、APS组、SB组、及APS+SB组中TNF-α、NF-κB、p-p38MAPK表达水平均明显升高（P值均小于0.05）;与I/R组比较,APS组、SB组及黄芪APS+SB组中TNF-α、NF-κB和p-p38MAPK表达水平明显降低（P值均小于0.05）。APS+SB组对TNF-α、NF-κB、和p-p38的蛋白表达抑制作用要显著强于APS组的抑制作用（P值均小于0.05）。结论：黄芪多糖和p38MAPK阻断剂（SB203580）均能够有效改善未成年大鼠的心肌缺血再灌注损伤时的炎症反应,黄芪多糖和SB203580联用可以明显抑制TNF-α和NF-κB的表达,抑制p38MAPK信号通路,具有抑制心肌缺血再灌注损伤的协同作用。     

p38 MAPK and MMP-9 cooperatively regulate mucus overproduction in mice exposed to acrolein fog

ObjectiveTo evaluate the role of p38 mitogen-activated protein kinase (MAPK) on mice airway inflammation, mucus production and the possible cross-talk between p38 MAPK and matrix metalloproteinase-9 (MMP-9) in mucin protein synthesis.MethodsMice were exposed to 4.0 ppm of acrolein for 21 days with daily intraperitoneal injection of SB203580, a specific inhibitor of p38 MAPK. In control mice, sterile saline was administered instead. On days 7 and 21, mice were sacrificed to examine airway inflammation and mucus production by BALF cell counts, cytokine ELISA, and H&;E and AB-PAS staining. The mRNA and protein levels of Muc5ac, p38 MAPK and MMP-9 in the lung were determined by RT-PCR, immunohistochemistry and Western blotting analysis. MMP-9 activity was measured by gelatin zymography.ResultsBoth the numbers of inflammatory cells and mucus-secreting goblet cells were significantly increased in the airways of mice exposed to acrolein as compared to the control mice. Acrolein-increased phosphorylation of p38 MAPK was significantly reduced by SB203580. The airway inflammation and goblet cell hyperplasia after acrolein challenge were also attenuated by SB203580 administration. Moreover, SB203580 treatment decreased the acrolein-induced increase of Muc5ac and MMP-9 expression and MMP-9 activity in airway epithelium.ConclusionsThe results indicate an important role of p38 MAPK in acrolein-induced airway inflammation and mucus hypersecretion in mice. The cooperation of p38 and MMP-9 may contribute to the mucin overproduction after inflammatory challenge.     

p38MAPK介导的Fas/FasL凋亡通路在缺血性脑损伤中的作用研究

目的探讨p38MAPK介导的Fas/FasL凋亡通路在大鼠缺血性脑损伤中的作用。方法①制作大鼠全脑缺血模型,免疫印迹法检测假手术组、脑缺血复灌6 h、12 h、1 d、3 d组p-p38MAPK、p38MAPK蛋白表达。②免疫印迹法检测假手术组、缺血复灌组、溶剂对照组和SB203580组p-p38MAPK、p38MAPK、FasL、Fas和Caspase-3蛋白表达。结果①与假手术组相比,脑缺血再灌注6 h、12 h、1 d、3 d组p-p38MAPK蛋白表达水平逐渐升高,于1 d达高峰(P均<0.05)。②与缺血复灌组和溶剂对照组相比,SB203580组p-p38MAPK、FasL和Caspase-3表达水平显著降低(P均<0.05)。结论 p38MAPK介导的Fas/FasL凋亡通路在缺血性脑损伤中发挥了重要作用。     

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.     

唑来膦酸盐通过p38 MAPK信号通路调控高糖微环境下成骨细胞分化

目的 探讨唑来膦酸盐（ZOL）对高糖微环境下小鼠前成骨细胞MC3T3-E1成骨分化的影响及p38丝裂原活化蛋白激酶（p38 MAPK）通路的调节作用。方法 体外培养MC3T3-E1细胞并分为低糖（LG）组、LG+ZOL组、高糖（HG）组、HG+ZOL组。ZOL为0.1μmol/L,LG、HG的葡萄糖浓度分别为5.5 mmol/L和16.5 mmol/L。采用四甲基偶氮唑蓝（MTT）法检测细胞增殖水平;鬼笔环肽染色观察细胞骨架;试剂盒检测细胞碱性磷酸酶（ALP）活性;茜素红染色检测细胞矿化结节生成情况;免疫荧光法检测Wnt5a、p38 MAPK的荧光表达强度。另设HG+ZOL+p38 MAPK通路抑制剂（SB203580）组,SB203580为10μmol/L。Western blot检测5组细胞中Wnt5a、p38 MAPK、磷酸化p38丝裂原活化蛋白激酶（p-p38 MAPK）、骨形态发生蛋白2(BMP2)和Ⅰ型胶原蛋白（COLⅠ）的表达水平。结果 4组细胞增殖水平差异无统计学意义（P>0.05）。与LG组比较,LG+ZOL组细胞骨架清晰程度,ALP活性,茜素红矿化结节生成,W...     

己酮可可碱对大鼠脓毒症急性肺损伤p38MAPK活性的影响

目的探讨己酮可可碱（pentoxifylline,PTX）对腹腔感染致脓毒症急性肺损伤发挥肺保护作用与p38MAPK活化的关系。方法采用盲肠结扎穿孔致脓毒症模型,将大鼠随机分为Ⅰ组（Sham组）、Ⅱ组（脓毒症CLP组）、Ⅲ组（脓毒症加西黄著胶CLP＋V组）、Ⅳ组（脓毒症加生理盐水CLP＋N组）、Ⅴ组（脓毒症加SB203580 CLP＋SB组）、Ⅵ组（脓毒症加己酮可可碱CLP＋PTX组）,其中Ⅲ组、Ⅳ组为溶媒对照组。用Western Blot检测假手术组,脓毒症1,3,6,12,24 h后p38MAPK的磷酸化,然后选择1,6,24 h分别检测应用SB203580或PTX后p38MAPK的表达,同时检测血浆TNF-α、IL-6的含量并观察24 h内肺组织病理改变。结果与假手术组比较,脓毒症组在各个时间点p38MAPK均有较强的表达,SB203580或PTX预处理后各组的p38MAPK的磷酸化明显受到抑制,且与血浆TNF-α、IL-6的含量以及肺的病理切片变化一致。结论己酮可可碱可能是通过抑制p38MAPK的磷酸化抑制促炎因子的过度表达,发挥对脓毒症急性肺损伤的保护作用。     

钩藤碱固体脂质纳米粒对哮喘小鼠miR-155/p38 MAPK轴的影响

目的　观察钩藤碱固体脂质纳米粒（Rhy-SLN）对支气管哮喘模型小鼠微小RNA-155（miR-155）/p38丝裂原活化蛋白激酶（p38 MAPK）轴的影响。方法　15只BALB/c小鼠随机均分为正常对照组、模型组和Rhy-SLN组。Rhy-SLN组小鼠行鼻内氢氧化铝致敏操作前以Rhy-SLN（50 mg/kg）灌胃;正常对照组和模型组给予等量生理盐水。干预结束后,肺泡灌洗液涂片观察嗜酸粒细胞的数量;HE染色观察小鼠肺组织病理改变情况;酶联免疫吸附试验（ELISA）法检测小鼠免疫球蛋白E（IgE）、白细胞介素（IL）-13水平;羟脯氨酸测试盒检测小鼠肺组织中羟脯氨酸水平;Werstern blot检测小鼠肺组织（α-SMA）、胶原蛋白Ⅰ（collagen Ⅰ）、p38 MAPK、p-p38 MAPK蛋白表达水平;荧光定量聚合酶链反应（qPCR）检测小鼠肺组织miR-155 mRNA表达水平。结果　与模型组比较,Rhy-SLN组可以降低哮喘小鼠肺泡灌洗液中嗜酸粒细胞的数目、血清中IgE和肺泡灌洗液中IL-13的水平（P＜0.05）;减轻肺组织炎性细胞浸润;降低肺组织中α-SMA、collagenⅠ、羟脯氨酸和p-p38 MAPK的表达（P＜0.05）;上调小鼠肺组织中miR-155的表达水平（P＜0.05）。结论　Rhy-SLN可缓解小鼠哮喘,其机制可能与调节miR-155/p38 MAPK轴,降低气道的炎症反应有关。     

p38 MAPK mediates cardiovascular and behavioral responses induced by central IL-1 beta and footshock in conscious rats.

AIM: To investigate the roles of p38 mitogen-activated protein kinase (p38 MAPK) in the cardiovascular and behavioral responses induced by intracerebral ventricular injection (i.c.v.) of interleukin-1 beta (IL-1 beta) or footshock. METHODS: We examined the effects of p38 MAPK on mean artery blood pressure (mABP), heart rate (HR), and motor activity (MA) during central administration of IL-1 beta, or footshock after i.c.v. SB203580 (a specific inhibitor of the p38 MAPK) with Cardiovascular and Behavior Telemetry System in conscious SD rats. RESULTS: (1) IL-1 beta (i.c.v.) or footshock remarkably rise the mABP, and the maximal changes are (7.8+/-1.8) and (12.3+/-3.5) mmHg, respectively, which was abrogated by the pretreatment with p38 inhibitor SB203580 intracerebroventricularly. (2) Compared with icv saline group, the motor activity was significantly decreased in SB203580 group with maximal changes (-7.6+/-1.1) counts/min after footshock. CONCLUSION: p38 MAPK plays an important role in the pressor response induced by central administration of IL-1 beta or footshock and change of motor activity after footshock in conscious rats.     

p38MAPK inhibition attenuates LPS-induced acute lung injury involvement of NF-kappaB pathway

The pathogenesis of acute lung injury/acute respiratory distress syndrome (ARDS) is complex and involves multiple signal transduction processes. It is believed that p38MAPK (mitogen-activated protein kinase) is one of the most kinases in inflammatory signaling. At present study, we demonstrated the role of p38MAPK in lipopolysaccharide (LPS)-induced acute lung injury with pharmacologic p38MAPK inhibition by SB203580. SB203580, p38MAPK specific inhibitor, was injected (10 mg/kg, i.v.) 30 min before LPS administration (5 mg/kg, i.v.). The hematoxylin-eosin staining of lung tissues showed that p38MAPK inhibition significantly attenuated the pulmonary inflammatory responses induced by LPS. Moreover, SB203580 can also inhibit the inflammatory cytokine release, and reduce the mortality rate of LPS-induced acute lung injury. Further, western blot analysis that showed SB203580 administration can inhibit the activation of NF-kappaB, which was associated with the inhibition of IkappaBalpha degradation in cytoplasm. These data suggest that p38MAPK signaling may be involved in the activation of NF-kappaB, and activation of p38MAPK signaling may be one of the mechanisms of acute lung injury.     

己酮可可碱弱化大鼠脓毒症急性肺损伤对p38MAPK/IκBα磷酸化的影响

目的探讨己酮可可碱（pentoxifylline,PTX）对腹腔感染致脓毒症急性肺损伤发挥保护作用的上游信号机制。方法采用盲肠结扎穿孔（cecal ligation and puncture,CLP）致脓毒症模型,将大鼠随机分为假手术组、脓毒症组、脓毒症＋西黄著胶组、脓毒症＋生理盐水组、脓毒症＋SB203580组、脓毒症＋PTX组。检测假手术组、脓毒症组各时间点（1,3,6,12,24 h）p38MAPK及IκBα的磷酸化,然后选择1,6,24 h组分别检测应用SB203580或PTX后p38MAPK及IκBα的表达,同时检测血浆TNF-α、IL-6的含量并观察24 h组肺组织病理改变。结果与假手术组比较,脓毒症组在各个时间点p38MAPK及IκBα均有较强的表达,SB203580或PTX预处理后各组的p38MAPK及IκBα的磷酸化明显受到抑制,且与血浆TNF-α、IL-6的含量以及肺的病理切片变化一致。结论 PTX对脓毒症急性肺损伤的保护作用以及抑制促炎因子产生的作用可能是通过抑制p38MAPK的磷酸化从而抑制NF-κB的活化而产生的。     

Aspergillus fumigatus-induced early inflammatory response in pulmonary microvascular endothelial cells: Role of p38 MAPK and inhibition by silibinin

Human invasive pulmonary aspergillosis (IPA) is a serious infectious disease mainly caused by Aspergillus fumigatus (A. fumigatus). Pulmonary microvascular endothelial cells (PMVECs) are important ones in the human lung tissue. However, it remains unclear about the role of PMVECs in IPA. In the present study, we cocultured PMVECs with A. fumigatus. We observed that A. fumigatus induced dose- and time-dependent increases of interleukin 6 (IL-6), interleukin 1β (IL-1β) and intercellular adhesion molecule 1 (ICAM-1) concentration in the cultures. Significant increases in IL-6, IL-1β, E-selectin, and ICAM-1 mRNA expression were also observed in the cultures treated with A. fumigatus. While preincubation with SB203580 (10 μM) did not cause significant changes in IL-6, IL-1β and ICAM-1 concentration in the cocultures, significant IL-6, IL-1β and ICAM-1 concentration decreases were observed in the cocultures preincubated with SB203580 (20 μM). Neither SP600125 (10-20 μM) nor PD98059 (10-20 μM) caused significant changes in IL-6, IL-1β and ICAM-1 concentration in the cocultures. PCR results also showed that SB203580 (20 μM) (neither SP600125 (20 μM) nor PD98059 (20 μM)) preincubation significantly decreased IL-6, IL-1β, E-selectin and ICAM-1 mRNA expression in the cocultures. In addition, significant p38 MAPK phosphorylation increase was observed in the PMVECs cultures treated with A. fumigatus. Furthermore, silibinin pre-treatment and post-treatment were observed to significantly down-regulate mRNA and protein expression of proinflammatory factors and adhesion molecules in the cocultures. Finally, we observed that silibinin significantly inhibited A. fumigatus-induced p38 MAPK activation in PMVECs. Our results indicated that PMVECs might participate in IPA early inflammation which is mediated by p38 MAPK. Silibinin may inhibit A. fumigatus-induced inflammation in PMVECs through p38 MAPK.     

FTY-720通过TGF-β1/P38 MAPK/NF-κB信号通路对小鼠肺纤维化模型的影响

目的探讨FTY-720对博来霉素诱导的小鼠肺纤维化的影响及其作用机制。方法将40只无特定病原体级健康雄性Balb/c小鼠随机分为对照组、博来霉素组、生理盐水+FTY-720对照组、博来霉素+FTY-720组,每组各5只,在7天、14天处死小鼠,共8组。应用HE染色和Masson染色观察肺组织炎症及肺纤维化情况;通过瑞士-吉姆萨染色计数支气管肺泡灌洗液细胞;BCA法测定BALF蛋白含量;ELISA方法检测BALF上清液中炎症因子IL-1β、TNF-α的表达水平;免疫组织化学法检测肺组织中COL1A1的表达水平;Western blot方法检测TGF-β1、p-P38 MAPK和NF-κB表达水平的变化。结果FTY-720显著降低BLM诱导增加的小鼠肺组织细胞外胶原沉积;减少小鼠肺组织BALF中IL-1β和TNF-α表达水平,和蛋白质含量、细胞数;FTY-720抑制TGF-β1活性与P38 MAPK的磷酸化,进而抑制NF-κB的表达与活化。结论FTY-720通过抑制TGF-β1/P38 MAPK/NF-κB信号通路,进而抑制博来霉素诱导小鼠的肺纤维化。     

p38 Mitogen-activated protein kinase up-regulates LPS-induced NF-kappaB activation in the development of lung injury and RAW 264.7 macrophages

Clarification of the key regulatory steps that lead to nuclear factor-kappa B (NF-kappaB) under cellular and pathological conditions is very important. The action of p38 mitogen-activated protein kinase (MAPK) on the upstream of NF-kappaB activation remains controversial. To examine this issue using an in vivo lung injury model, SB203580, a p38 MAPK inhibitor was given intraorally 1h prior to lipopolysaccharide (LPS) treatment (intratracheally). The mice were sacrificed 4 h after LPS treatment. SB203580 substantially suppressed LPS-induced rises in p38 MAPK phosphorylation, neutrophil recruitment, total protein content in bronchoalveolar lavage fluid, and apoptosis of bronchoalveolar cells. Furthermore, SB203580 blocked LPS-induced NF-kappaB activation in lung tissue through down-regulation of serine phosphorylation, degradation of IkappaB-alpha, and consequent translocation of the p65 subunit of NF-kappaB to the nucleus. It is likely that, in cultured RAW 264.7 macrophages, SB203580 also blocked LPS-induced NF-kappaB activation in a dose-dependent manner. SB203580 inhibited LPS-induced serine phosphorylation, degradation of IkappaB-alpha, and tyrosine phosphorylation of p65 NF-kappaB. These data indicate that p38 MAPK acts upstream of LPS-induced NF-kappaB activation by modulating the phosphorylation of IkappaB-alpha and p65 NF-kappaB during acute lung injury. Because LPS-stimulated macrophages may contribute to inflammatory lung injury, the inhibition of the p38 MAPK-mediated intracellular signaling pathway leading to NF-kappaB activation represents a target for the attenuation of lung inflammation and parenchymal damage.     

广州城区大气细颗粒物对PC-12细胞IL-8表达的影响

目的 研究广州城区大气细颗粒物(PM2.5)对PC-12细胞IL-8表达的影响,并从p38 MAPK途径探索其作用机制,促进对PM2.5毒性的认识.方法 采集广州城区大气中的PM2.5,对PC-12细胞染毒,设对照组、不同浓度PM2.5组和SB203580+PM2.5组(用20 μ mol/L的SB230580预处理1h后再给予100μg/ml的PM2.5),Trizol法提取RNA用定量PCR法检测细胞IL-8表达情况,RIRP法提取细胞总蛋白,用Western blot法检测p38 MAPK的磷酸化改变.结果 定量PCR检测显示用25、50和100μg/ml的PM2.5染毒后PC-12细胞IL-8表达明显增高;Western blot结果显示PM2.5可磷酸化激活p38 MAPK信号分子,加入p38 MAPK抑制剂SB230580可以抑制PM2.5诱导的IL-8表达.结论 PM2.5可通过p38 MAPK途径诱导PC-12细胞表达细胞因子IL-8,这可能是其导致神经细胞毒性的机制之一.