Expression of MMP2, MMP9 and MMP3 in Breast Cancer Brain Metastasis in a Rat Model

In order to study the expression of MMP2, MMP3 and MMP9 in breast cancer brain metastasis, we used a syngeneic rat model of distant metastasis of ENU1564, a carcinogen-induced mammary adenocarcinoma cell line. At six weeks post inoculation we observed development of micro-metastasis in the brain. Immunohistochemistry and Western Blotting analyses showed that MMP-2, -3 and -9 proteins expressions are consistently significantly higher in neoplastic brain tissue compared to normal brain tissue. These results were confirmed by RT-PCR. In situ zymography revealed gelatinase activity within the brain metastasis. Gel zymography showed increase in MMP2 and MMP3 activity in brain metastasis. Furthermore, we were able to significantly decrease the development of breast cancer brain metastasis in animals by treatment with PD 166793, a selective synthetic MMP inhibitor. In addition, PD 166793 decreased the in vitro invasive cell behavior of ENU1546. Together our results suggest that MMP-2, -3 and -9 may be involved in the process of metastasis of breast cancer to the brain.     

缺氧缺血脑损伤大鼠脑组织Cofilin 1与ERK1/2蛋白表达与磷酸化的分析

目的探索新生大鼠缺氧缺血脑损伤模型脑组织Cofilin1与ERK1/2蛋白表达与磷酸化及其在脑组织中分布的规律。方法新生7日龄SD大鼠,手术结扎左侧颈总动脉并经低氧处理造成缺氧缺血脑损伤(HIBD)模型,以假手术组为对照,应用western Blot和免疫组化方法检测损伤后一定时间段(0h～48h)损伤侧脑组织Cofilin1与磷酸化cofilin1(p-Cofilin1)及Erk1/2和磷酸化ERK1/2(p-ERK1/2)的表达变化,同时检测其在损伤大鼠脑组织和细胞中的表达和分布。结果 Western blot检测显示,HIBD新生SD大鼠脑组织中Cofilin1在HI后的表达与对照组相比也未见明显改变,但磷酸化Cofilin1在HI后1h～12h之间降低,24h后恢复正常;ERK1/2蛋白在不同时点的表达与对照组相比未见明显差异,但可见磷酸化ERK1/2(p-ERK1/2)在缺氧缺血处理(HI)后0h略低于正常,而在1-2h内迅速升高并高于正常对照和假手术,在2h后又逐渐降低。免疫组化结果显示Cofilin1与p-cofilin1在损伤大鼠脑中主要分布于海马和大脑皮质,尤其p-Cofilin表达分布以海马的颗粒细胞为主,并且在HI后7d-14d表达明显增强,在21d则明显降低。结论 Cofilin和ERK的磷酸化修饰与缺氧缺血脑损伤的发生和发展过程有较密切的关系,且cofilin1和p-cofilin1在大脑海马区的定位分布,提示其可能与大脑的学习记忆功能的损伤与修复有一定的关系。     

Characterization of brain and bone-metastasizing clones selected from an ethylnitrosourea-induced rat mammary carcinoma

An animal model for breast cancer, brain and bone metastasis was developed using ENU1564, a cell line established from a metastatic mammary adenocarcinoma induced by N-ethyl-N-nitrosourea in a female Berlin-Druckrey IV rat. The original tumor isolate (designated FP1) spontaneously metastasizes to regional lymph nodes and lung following orthotopic inoculation into mammary fat pad (mfp) and metastasizes widely following left cardiac ventricle (LV) inoculation. From FP1, two sublines were selected from brain metastases (designated Br7-C5) or from slowly growing coloniesin vitro (FP2-A11), then cloned and compared in assays of spontaneous and experimental metastasis. After inoculation of 10⁵ cells into mfp, Br7-C5 formed large tumors at the inoculation site (9.4±3.3 g) and spontaneously metastasized to lung and lymph node by 55 days post-inoculation (dpi). In contrast, FP2-A11 produced much smaller tumors within mfp (0.6±0.3 g) and failed to metastasize by 55 dpi. Rats inoculated via the LV with 10⁴ Br7-C5 cells developed signs of weight loss, head tilt, and dyspnea by 24±1.4 dpi with consistent colonization of brain, bone, lung, heart, kidney, and stomach. Rats inoculated similarly with FP2-A11 showed no signs until 53±12.3 dpi, when all developed rear limb paresis. There was significant colonization of only brain and bone, with only minor lung involvement. These ENU1564 sublines thus differ in their apparent rates of tumor growth and lesion developmentin vivo, their capacity to metastasize from orthotopic implantation sites, and in the spectrum of tissues colonized in experimental metastasis assays. Both clones provide reproducible models of breast cancer metastasis in syngeneic hosts, particularly to brain and bone.     

外源性BDNF对急性高眼压后大鼠视网膜ERK1/2磷酸化的影响

为研究脑源性神经生长因子(BDNF)干预对急性高眼压后大鼠视网膜磷酸化的细胞外信号调节激酶(p-ERK1/2)表达变化的影响,本实验将成年大鼠随机分为单纯高眼压组、BDNF预处理高眼压组和溶媒预处理高眼压组,BDNF预处理高眼压组和溶媒预处理高眼压组动物左眼于加压前2d分别给予BDNF或溶媒预处理,右眼设为正常对照。各组动物左眼眼压升高至闪光视网膜电图b波消失的临界眼压并维持60min,动物分别存活1、3、7、14d后处死,冰冻切片行p-ERK的免疫组织化学染色。结果显示与正常对照相比,单纯高眼压组急性高眼压后p-ERK表达下调(P<0.05),1、3、7d组内核层出现p-ERK阳性细胞;溶媒预处理高眼压组实验结果与单纯急性高眼压组相似;BDNF预处理高眼压组急性高眼压后1、3、7d时p-ERK的表达与正常对照组相似,7d和14d出现了重新分布。此结果提示外源性BDNF可能通过促进急性高眼压后视网膜ERK1/2的活化对受损的视网膜起保护作用。     

Adipophilin通过ERK1/2-AP-1途径诱导炎症因子的表达

目的:观察巨噬细胞中脂肪分化相关蛋白(adipophilin)对炎症因子表达的影响,阐明adipophilin促进巨噬细胞炎症因子表达的机制。方法:将已构建成功的adipophilin稳定高、低表达逆转录病毒载体转染入PA317包装细胞,制备adipophilin高和低表达的RAW264.7细胞;收集已转染成功的各组细胞上清液,用ELISA方法检测IL-6、TNF-α、MCP-1等炎症因子在细胞培养液中的浓度。Western blot检测各组细胞AP-1、p-AP-1、ERK1/2及p-ERK1/2的蛋白水平;用ERK1/2抑制剂PD98059或AP-1抑制剂curcumin孵育细胞,检测各组细胞中以上指标的变化情况。结果:高表达adipophilin的细胞上清液中炎症因子IL-6、MCP-1和TNF-α浓度明显增高,adipophilin siRNA组细胞中的炎症因子降低;高表达adipophilin的细胞中p-ERK1/2和p-AP-1的蛋白水平增高,adipophilin siRNA组则减少;ERK1/2抑制剂PD98059使AP-1蛋白活性明显下调;给予AP-1抑制剂curcumin后,细胞培养液中的IL-6、MCP-1和TNF-α浓度明显下降。结论:Adipophilin在RAW264.7巨噬细胞中能够促进炎症因子的表达。     

ERK1/2/PPARα/SCAD信号途径对生理性和病理性心肌肥大的调控

 目的：研究ERK1/2/PPARα/SCAD（短链脂酰辅酶A脱氢酶）信号途径对生理性和病理性心肌肥大调控的不同机制,探索病理性心肌肥大治疗的新靶点。方法：分别以胰岛素样生长因子1（insulin-like growth factor 1,IGF-1）和苯肾上腺素（phenylephrine,PE）刺激心肌细胞,复制生理性和病理性心肌肥大模型,检测心肌细胞表面积,p-ERK1/2和PPARα蛋白表达变化,SCAD mRNA、蛋白表达和酶活性变化,心肌细胞游离脂肪酸含量变化。结果：与对照组比较,PE和IGF-1刺激后心肌细胞表面积均显著增大。与对照组相比,IGF-1刺激的心肌细胞SCAD mRNA和蛋白表达均上调,酶活性显著增高,游离脂肪酸含量明显减少,且PPARα mRNA和蛋白表达均上调,p-ERK1/2的蛋白表达显著下调;PE刺激的心肌细胞SCAD mRNA和蛋白表达均下调,酶活性显著降低,游离脂肪酸含量明显增加,且PPAR αmRNA和蛋白表达均下调,p-ERK1/2蛋白表达显著上调。结论：p-ERK1/2/PPARα/SCAD在生理性和病理性心肌肥大中呈现出不一致的变化趋势,表明ERK1/2/PPARα/SCAD信号途径对2种不同肌肥大的调控作用不同。SCAD可能作为2种不同心肌肥大的分子标志物及病理性心肌肥大的潜在治疗靶点。     

MMP—2和MMP—9在人脑原发性胶质瘤侵袭中的作用

目的 探讨基质金属蛋白酶MMP－2和MMP－9在原发性人脑胶质瘤侵袭行为中的作用。方法 用免疫组织化学S－P法检测MMP－2和MMP－9在胶质瘤和脑内转移瘤中的表达情况;同时通过测量CT影像上的瘤周水肿范围,并与免疫组织化学表达结果作对照比较。结果 1.45例人脑胶质瘤档本中,MMP－2和MMP－9的瘤细胞阳性率分别为35.5%、62.2%,两者之间差别显著（P＜0.05）;MMP－2、MMP－9在高度恶性胶质瘤标本中阳性率分别为56.5%、91.3%,两者之间亦存在明显差别（P＜0.01）;2.MMP－2的染色强度与胶质瘤侵袭指标－－CT瘤周水肿范围无关（P＞0.05）,而MMP－9的染色强度则与其有关（P＜0.05）;也与高度恶性胶质瘤中的表达率无统计学差别（P＞0.05）。结论 MMP－2、MMP－9在人脑胶质瘤中可以作为恶性表型及侵袭指标之一,亦可体现胶质瘤基质降解表型,但不能作为转移表型。其中,MMP－9在人脑胶质瘤侵袭中可能发挥着更重要的作用。     

CSF1通过CSF1R/PLCG2/ERK/Nrf2信号通路减少缺氧缺血性脑病大鼠神经元凋亡

目的:探讨集落刺激因子1(CSF1)通过CSF1受体(CSF1R)减轻缺氧缺血性脑病(HIE)大鼠神经元凋亡的下游信号通路.方法:采用原代大鼠皮质神经元建立氧糖剥夺(OGD)神经元损伤模型,重组人CSF1(rh-CSF1)干预该模型,通过CCK-8和MTT检测细胞活力,测定LDH漏出,Western blot检测CSF...     

Significance of BRCA1 expression in breast and ovarian cancer patients with brain metastasis – A multicentre study

PurposeCerebral metastases develop in 10–30% of patients with breast cancer (BC) and in around 3.3 to 4% of patients with ovarian cancer (OC). The aim of the multicenter study is to investigate the correlation between the expression of estrogen alpha receptors (ERα), progesterone receptors (PR), human epidermal growth factor receptor 2 (HER2), stromal cell-derived factor 1 (SDF1) and its receptor C-X-C chemokine receptor type 4 (CXCR4), breast cancer metastasis suppressor 1 (BRMS1), astrocyte elevated gene 1 (AEG1), depending on the status of BRCA1 protein, in patients suffering from OC and BC with brain metastases.Patients and methodsThe analysis included 51 patients: 29 with BC and 22 with OC, in whom brain metastases were disclosed.ResultsIn most patients (65.5% of BC patients and 68.2% of patients with OC tumors) BRCA1 protein loss was found. No correlation was disclosed between the levels of ERα, PR receptors, HER2, SDF1, CXCR4, AEG1, BRMS1 and BRCA1 status, patient age, stage of disease advancement, grade of histological maturity of the cells, presence of metastases to lymph nodes. A statistically significant correlation was disclosed between the negative expression of PR receptors and a high expression of CXCR4 in patients with BC. High values of the AEG1 protein (linked to metastases) were detected alongside a high expression of BRMS1 (a suppressor of metastases).ConclusionsPatients with BC and OC and brain metastases have a frequent loss of BRCA1 expression. The role of ERα, PR, HER2, SDF1, CXCR4, AEG1, BRMS1 in metastatic process needs further studies.     

miR-145-5p靶向TPM3通过ERK信号通路抑制甲状腺癌TPC-1细胞侵袭和转移

目的 探讨miR-145-5p对甲状腺癌细胞侵袭和转移的影响.方法 将miR-145-5p mimic质粒、mimic-NC质粒、TPM3质粒分别或联合转入甲状腺癌细胞,RT-qPCR检测miR-145-5p与TPM3 mRNA的表达,双荧光素酶报告检测靶向关系,Transwell法检测细胞侵袭能力,划痕实验检测细胞迁...     

Adrenomedullin and adrenotensin regulate collagen synthesis and proliferation in pulmonary arterial smooth muscle cells

To understand the pathophysiological mechanisms of pulmonary arterial smooth muscle cell (PASMC) proliferation and extracellular-matrix accumulation in the development of pulmonary hypertension and remodeling, this study determined the effects of different doses of adrenomedullin (ADM) and adrenotensin (ADT) on PASMC proliferation and collagen synthesis. The objective was to investigate whether extracellular signal-regulated kinase (ERK1/2) signaling was involved in ADM- and ADT-stimulated proliferation of PASMCs in 4-week-old male Wistar rats (body weight: 100-150 g, n=10). The proliferation of PASMCs was examined by 5-bromo-2-deoxyuridine incorporation. A cell growth curve was generated by the Cell Counting Kit-8 method. Expression of collagen I, collagen III, and phosphorylated ERK1/2 (p-ERK1/2) was evaluated by immunofluorescence. The effects of different concentrations of ADM and ADT on collagen I, collagen III, and p-ERK1/2 protein expression were determined by immunoblotting. We also investigated the effect of PD98059 inhibition on the expression of p-ERK1/2 protein by immunoblotting. ADM dose-dependently decreased cell proliferation, whereas ADT dose-dependently increased it; and ADM and ADT inhibited each other with respect to their effects on the proliferation of PASMCs. Consistent with these results, the expression of collagen I, collagen III, and p-ERK1/2 in rat PASMCs decreased after exposure to ADM but was upregulated after exposure to ADT. PD98059 significantly inhibited the downregulation by ADM and the upregulation by ADT of p-ERK1/2 expression. We conclude that ADM inhibited, and ADT stimulated, ERK1/2 signaling in rat PASMCs to regulate cell proliferation and collagen expression.     

Edaravone对大鼠弥漫性脑创伤后ERK1/2通路的影响

为探讨Edaravone对脑创伤的保护机制,本研究观察了Edaravone对弥漫性脑创伤大鼠脑组织磷酸化细胞外信号调节激酶ERK1/2表达变化的影响。114只雄性SD大鼠,随机分为3组:(1)假手术对照组(A组,n=18),(2)创伤组(B组,n=48),(3)Edaravone治疗组(C组,n=48),采用Marmarou’s法建立大鼠弥漫性颅脑损伤模型。伤后1、3、6、24、48和72h,HE染色观察伤后皮质和海马区神经细胞组织形态变化,Western blot法、免疫组化法检测皮质和海马区p-ERK1/2的表达,术后24、48、72h对大鼠神经运动功能和综合运动能力评分。结果显示:光镜下,伤后6、24h即可见B组大脑皮质和海马区神经细胞胞体收缩呈三角形,胞浆嗜色性减弱,核皱缩浓染,细胞周围出现空隙,即神经细胞变性坏死改变,C组上述改变明显减轻;免疫组化与Western blot法结果显示,与A组比较,B组ERK1/2(即p-ERK1/2)活性在伤后1、3、6、24、48h显著增高(P<0.05);与B组比较,C组中p-ERK1/2在6、24及48h显著回降(P<0.05);神经功能与综合运动能力评分在B组中(8.73±1.4,63.8±27.7)明显低于A组(24.00±0.00,278.4±27.7),C组(17.36±1.63,117.6±20.9)显著回升(P<0.05)。本研究表明Edaravone可改善脑创伤后神经功能损伤,其机制与调节脑创伤后ERK1/2信号活化水平有关。     

Activation of the extracellular signal regulated kinase (ERK) pathway in human melanoma

BACKGROUND: Several studies suggest that melanoma may be resistant to treatment because of resistance to apoptosis and that this may be the result of activation of the extracellular signal regulated kinase (ERK1/2) pathway. AIMS: To test this hypothesis by examining the expression of ERK1/2 and its activated form in histological sections of melanoma and its relation to known prognostic features of the disease. MATERIALS/METHODS: Immunohistochemistry with antibodies to ERK1/2 and phosphorylated ERK (p-ERK) was performed on formalin fixed sections from 42 primary melanomas, 38 metastases, and 20 naevi. Fourteen of the primary melanomas were in the radial and 28 in the vertical growth phase. RESULTS: ERK1/2 was widely expressed (100%) in all the (pigmented) lesions studied. p-ERK1/2 expression was much lower in compound (32.4%) and dysplastic (54.5%) naevi than in primary melanoma (nodular 78.8%, superficial spreading 67%) and subcutaneous metastases (76.3%). p-ERK expression was much lower in lymph node metastases (48.5%), suggesting that the microenvironment may influence the activation of ERK. There was a (non-significant) trend for p-ERK expression to be higher in thick (>1.0 mm) versus thin (< or =1.0 mm) melanoma (p = 0.23). There was a trend for overall survival to be related to p-ERK expression in patients with melanoma over 1 mm in thickness. CONCLUSIONS: Expression of activated ERK1/2 in melanocytic lesions appears to be related to malignant potential so that activation of ERK1/2 may be important in melanoma progression. These results provide important histological support for the proposal that inhibition of this signalling pathway may be useful in treatment of melanoma.     

胰岛素对大鼠结肠平滑肌细胞凋亡及MAPK通路的影响

 目的 探讨胰岛素对大鼠结肠平滑肌细胞( SMCs )凋亡及丝裂原活化蛋白激酶( MAPK )信号转导通路的影响。方法 酶解法分离培养SD大鼠结肠SMCs,α-actin免疫鉴定,将大鼠结肠SMCs分为正常组,胰岛素组,胰岛素 +PD98059( ERK抑制剂)组,MTT法检测SMCs增殖,流式细胞术Annexin V-FITC/PI检测SMCs凋亡,Western blot法检测p-ERK、ERK、p-P38MAPK、P38MAPK和p-JNK、JNK表达。结果 胰岛素组较正常组细胞明显增殖,凋亡率降低,p-ERK表达增强,p-ERK/ERK 比值升高( 110.36 ± 9.5 vs 50.92 ± 6.01 ) ( P < 0.01 );p-P38MAPK、P38MAPK、p-JNK、JNK表达无差异。PD98059组较正常组细胞增殖明显下降,凋亡率升高,p-ERK表达减弱,p-ERK/ERK比值降低( 15.69 ± 2.11 vs 50.92±6.01 ) ( P < 0.01 )。结论 胰岛素可能通过激活结肠SMCs的MAPK通路中的ERK途径,促进细胞增殖,抑制凋亡,可能与P38MAPK途径和JNK途径无关。     

青蒿琥酯通过抑制ERK1/2蛋白活化负性调控HSC-T6细胞cyclin D1的表达和AP-1活性

目的: 通过观察青蒿琥酯(artesunate,Art)对肝星状细胞(hepatic stellate cells,HSCs)细胞外信号调节蛋白激酶1/2(extracellular signal-regulated kinase 1/2,ERK1/2)、激活蛋白1(activator protein 1,AP-1)和细胞周期蛋白D1(cyclin D1)的影响,探讨Art抗肝纤维化的分子机制。方法: 用血小板源性生长因子BB(platelet-derived growth factor BB, PDGF-BB)诱导HSC-T6细胞的增殖。实验分为对照组、PDGF-BB组、PDGF-BB+Art组(Art终浓度6.25 mg/L、25 mg/L、50 mg/L)和PDGF-BB+ERK抑制剂PD98059组。ELISA法测定细胞上清液中Ⅰ型胶原的含量,RT-PCR检测各组ERK1/2和cyclin D1 mRNA水平变化,Western blotting法检测各组p-ERK1/2和cyclin D1蛋白表达水平,凝胶电泳迁移率实验(EMSA)检测AP-1的活性。结果: (1)PDGF-BB 可明显促进HSC-T6细胞的增殖,PDGF-BB+Art各剂量组和PDGF-BB+PD98059均可抑制HSC-T6细胞上清液中Ⅰ型胶原的含量(P<0.05,P<0.01)。(2)PDGF-BB+Art组(50 mg/L)ERK1/2 mRNA的表达低于PDGF-BB组(P<0.05),其中PDGF-BB+PD98059组ERK1/2 mRNA的表达最低(P<0.01);PDGF-BB+Art组(25 mg/L、50 mg/L)和PDGF-BB+PD98059组cyclin D1 mRNA的表达明显低于PDGF-BB组(P<0.05,P<0.01)。(3)p-ERK1/2、cyclin D1蛋白表达水平在PDGF-BB组最高,而PDGF-BB+Art各剂量组和PDGF-BB+PD98059组降低(P<0.05,P<0.01)。(4)Art可使AP-1与DNA结合活性下降。结论: Art可抑制HSC-T6细胞增殖,其机制可能与其抑制ERK1/2蛋白活化从而降低AP-1的活性和下调cyclin D1的表达有关。     

ADM和ADT对肺动脉平滑肌细胞胶原合成及磷酸化ERK1/2表达的影响

目的: 检测不同浓度的肾上腺髓质素(ADM)和肾上腺加压素(ADT)对培养的Wistar大鼠肺动脉平滑肌细胞(PASMCs)Ⅰ、Ⅲ型胶原合成和磷酸化细胞外信号调节激酶(p-ERK1/2)表达的影响,探讨PASMCs增殖过程中ERK途径是否被激活。方法: 取健康雄性Wistar大鼠,行大鼠远端PASMCs分离并进行原代培养,采用小鼠抗人平滑肌α-actin单克隆抗体对培养细胞进行鉴定;在培养基内分别加入10^-7 mol/L ADM或ADT培养72 h 后加入兔抗大鼠Ⅰ型、Ⅲ型胶原抗体和兔抗大鼠p-ERK1/2抗体,0.01 mol/L PBS作阴性对照,FITC标记山羊抗兔IgG为Ⅱ抗,免疫荧光法观察PASMCs内Ⅰ、Ⅲ型胶原及p-ERK1/2表达。Western blotting检测10^-7mol/L、10^-8mol/L和10^-9 mol/L ADM或ADT对p-ERK1/2蛋白表达的影响。结果: 经平滑肌α-actin单克隆抗体对培养细胞进行鉴定,其纯度达97%。10^-7 mol/L ADM可抑制PASMCsⅠ、Ⅲ型胶原及p-ERK1/2的表达(P<0.05,P<0.01);10^-7 mol/L的ADT刺激后大鼠PASMCsⅠ、Ⅲ型胶原及p-ERK1/2的表达增强(P＜0.05,P<0.01)。Western blotting结果显示ADM可呈剂量依赖性抑制p-ERK1/2蛋白表达(P<0.01,P<0.05);而ADT也可呈剂量依赖性促进p-ERK1/2蛋白表达(P<0.01,P<0.05)。结论: ADM可抑制大鼠PASMCsⅠ、Ⅲ型胶原及p-ERK1/2表达,而ADT可促进PASMCsⅠ、Ⅲ型胶原及p-ERK1/2表达,提示PASMCs增殖过程中ERK通路被激活,ADM和ADT可能通过ERK1/2信号通路来调节PASMCs增殖。     

高氧、维甲酸对早产大鼠肺成纤维细胞MMP-2及TIMP-2表达的调控

目的:探讨维甲酸（RA）对高氧暴露下早产大鼠肺成纤维细胞（LFs）基质金属蛋白酶-2（MMP-2）及其特异性组织抑制物-2（TIMP-2）表达的影响。方法:建立原代培养的早产大鼠LFs高氧暴露模型,采用半定量RT-PCR方法检测MMP-2和TIMP-2 mRNA表达,明胶酶谱法检测MMP-2酶原和活酶表达, Western blotting检测其磷酸化和总的ERK1/2、JNK1/2、p38和c-Jun表达。结果:（1）与对照组比较,高氧可促进早产大鼠LFs MMP-2 mRNA及其酶原和活酶表达（P<0.05,P<0.01）,同时使其p-ERK1/2、p-JNK1/2、p-p38和p-c-Jun表达水平显著提高（P<0.01,P<0.05）;（2）RA能不同程度下调高氧诱导的早产大鼠LFs MMP-2 mRNA高表达和明显降低其p-JNK1/2、 p-p38和p-c-Jun表达（P<0.01,P<0.05）,但进一步提高p-ERK1/2表达;（3）高氧、RA对TIMP-2 mRNA和总ERK1/2、JNK1/2 、p38及c-Jun表达无明显影响。结论:高氧暴露通过激活MAPKs信号转导通路（主要是JNK和p38）使c-Jun磷酸化水平提高,促进MMP-2表达和激活;RA通过抑制JNK和p38磷酸化,下调MMP-2表达与活化,从而拮抗高氧诱导的肺损伤。     

Akt与ERK1/2在人骨关节炎软骨细胞中的表达

目的: 观察蛋白激酶B(Akt)与细胞外信号调节激酶1/2(ERK1/2)在正常和骨关节炎(OA)软骨细胞中的表达,探讨Akt与ERK1/2在OA病程中的意义。方法: 手术中取5例正常和18例OA人膝关节软骨组织,包埋制备切片,免疫组织化学技术观察 p-Akt及p-ERK1/2在正常和OA 软骨组织中的表达;培养人软骨细胞,甲苯胺蓝染色、免疫组化鉴定并观察聚集蛋白聚糖及Ⅱ型胶原在正常和OA软骨细胞中的表达; Western blotting技术检测Akt、p-Akt、ERK1/2、p-ERK1/2、磷酸化70 kD核糖体蛋白S6激酶(p-p70S6K)及增殖细胞核抗原(PCNA)蛋白在正常和OA软骨细胞中表达水平; 实时荧光定量PCR技术检测聚集蛋白聚糖及Ⅱ型胶原在正常和OA软骨细胞中mRNA表达水平。结果: 与正常软骨细胞比较,OA软骨细胞内p-Akt和p-p70S6K蛋白表达明显降低(P<0.05),且聚集蛋白聚糖和Ⅱ型胶原mRNA和蛋白在OA软骨细胞中的表达水平降低(P<0.05),而 p-ERK1/2和PCNA蛋白表达明显提高(P<0.05)。结论: Akt可能通过p-p70S6K来调控OA软骨细胞外基质聚集蛋白聚糖及II型胶原的合成,ERK1/2可能通过PCNA来调控OA软骨细胞增殖;Akt与ERK1/2可能参与了OA的病理过程。     

蛋白激酶B受体在大鼠脑星形胶质细胞的表达及其磷酸化

目的:研究大鼠脑星形胶质细胞蛋白激酶B受体(TrkB)的表达及其信号转导通路。方法:用生后2~3dSD大鼠,在无菌条件下取脑,制备细胞悬液,以胶质纤维酸性蛋白(GFAP)鉴定星形胶质细胞;以RT-PCR法研究星形胶质细胞TrkB、ERK1、ERK2 mRNA表达,用蛋白印迹和免疫细胞化学法研究星形胶质细胞TrkB、ERK1、ERK2蛋白表达。用蛋白印迹法检测脑源性神经营养因子(BDNF)作用后的星形胶质细胞p-TrkB。结果:星形胶质细胞的纯度达95%以上,RT-PCR结果显示星形胶质细胞表达TrkB、ERK1、ERK2 mRNA,蛋白印迹及免疫细胞化学法显示星形胶质细胞表达TrkB、ERK1、ERK2蛋白。BDNF作用1h后TrkB磷酸化,K252a可阻止TrkB磷酸化。结论:培养的大鼠星形胶质细胞表达TrkB、ERK1、ERK2;BDNF可使TrkB磷酸化,TrkB与星形胶质细胞信号转导有关。     

Spatio-temporal expression of cysteinyl leukotriene receptor-2 mRNA in rat brain after focal cerebral ischemia

Cysteinyl leukotrienes (CysLTs) induce inflammatory responses mediated by activating CysLT(1) and CysLT(2) receptors. We have recently reported that CysLT(1) receptor expression is increased in rat brain after focal cerebral ischemia and the increased expression is spatio-temporally related to acute neuronal injury and late astrocyte proliferation. Here we report spatio-temporal expression of CysLT(2) receptor mRNA in rat brain after focal cerebral ischemia induced by 30min of middle cerebral artery occlusion. We found that the neuron density was gradually decreased or disappeared in the ischemic core and boundary zone during 14 days after reperfusion, and the astrocyte population in the boundary zone was increased 3-14 days after reperfusion. In the ischemic core, the expression of CysLT(2) receptor mRNA was increased at 6, 12 and 24h and then recovered at 3, 7 and 14 days after reperfusion. In the boundary zone, the expression was significantly increased 3, 7 and 14 days after reperfusion. The results suggest that CysLT(2) receptor may be related to the acute neuronal injury and late astrocyte proliferation in the ischemic brain.