地高辛通过下调AEG-1表达抑制人胃癌MKN45细胞迁移和侵袭

本研究旨在观察地高辛对人胃癌MKN45细胞迁移和侵袭能力的影响,并探讨其分子机制。取人胃癌MKN45细胞作为研究对象,采用Transwell法检测细胞迁移和侵袭能力,通过脂质体转染法将星形细胞上调基因-1(astrocyte elevated gene-1,AEG-1)sh RNA干扰质粒转染MKN45细胞以构建低表达AEG-1的细胞株,利用Western blot法检测基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)、E-钙粘蛋白(E-cadherin)和AEG-1等蛋白的表达变化。结果显示,地高辛可使MKN45细胞迁移率和侵袭率均显著下降(P0.05),下调MMP-9和AEG-1蛋白表达水平(P0.05)以及上调E-cadherin蛋白表达水平(P0.05),上述作用均具有剂量依赖性。经sh RNA干扰AEG-1基因表达后,MKN45细胞中AEG-1蛋白表达水平显著下降(P0.05);同时AEG-1干扰组MKN45细胞中E-cadherin蛋白表达水平显著升高(P0.05),细胞迁移率、侵袭率和MMP-9蛋白表达水平均显著下降(P0.05)。上述结果提示,地高辛可在体外剂量依赖性地抑制人胃癌MKN45细胞迁移和侵袭,这可能与地高辛抑制AEG-1蛋白表达,继而下调MMP-9蛋白表达和上调E-cadherin蛋白表达有关。     

褪黑素的抗胃癌效应及其对TNF-α、NO表达的调节作用

目的 探讨褪黑素(melatonin, MLT)在体内外对胃癌细胞增殖活性的影响及其对肿瘤坏死因子-α(TNF-α)、一氧化氮(NO)表达的调节作用。方法 构建不同浓度褪黑素干预皮下荷胃癌小鼠模型。测量各组小鼠肿瘤质量、体积;胸腺、脾脏指数;HE染色观察肿瘤组织形态;分离各组小鼠腹水巨噬细胞并计数分析。ELISA和比色法检测外周血清及腹水巨噬细胞培养液TNF-α、NO表达水平。不同浓度褪黑素干预小鼠胃癌细胞(MFC)。CCK-8检测各组MFC细胞的增殖活力;ELISA和比色法检测各组细胞培养上清TNF-α、NO表达水平。结果 褪黑素干预后小鼠肿瘤质量、体积均显著下降,脾和胸腺指数无明显变化;相比对照组,褪黑素组外周血清和腹水巨噬细胞培养液TNF-α、NO表达水平均明显升高。褪黑素干预后MFC细胞增殖活力明显下降,呈剂量依赖性;同时,褪黑素组相比对照组MFC细胞上清NO表达降低,TNF-α表达升高。结论 褪黑素体内外均能抑制胃癌细胞增殖活性,该作用与TNF-α表达上调、NO表达水平改变有关;也与体内巨噬细胞分泌TNF-α、NO水平增强有关。     

细胞因子对血管平滑肌细胞MMP-2基因表达的诱导及其作用机制研究

为了探讨血管平滑肌细胞 ( VSMC)基质金属蛋白酶 - 2 ( MMP- 2 )基因的表达调控机制 ,利用Northern印迹杂交和 MMP- 2活性酶图分析检查 b FGF、TNF- α和 IL- 1 β对 VSMC MMP- 2基因表达的影响 ,应用电泳迁移率改变实验 ( EMSA)和 CAT分析对其作用机制进行研究 .结果证实 ,3种细胞因子均能显著诱导 MMP- 2基因表达 ,其作用强度依次为 b FGF>TNF-α>IL - 1β.将 MMP-2基因 5′侧翼 - 61 9～ 1 9bp调控序列克隆进携带报告基因的重组质粒 p SV0 - CAT后 ,经转染VSMC及 CAT分析显示 ,在上述 3种细胞因子的作用下 ,该调控序列可激活 cat基因表达 ,三者促进 cat表达的活性与其诱导 VSMC表达 MMP- 2的结果相一致 ;EMSA结果显示 ,被 b FGF和TNF- α刺激的 VSMC中产生与该基因调控区序列特异结合的转录调控因子 .提示细胞因子除可激活 VSMC细胞周期调节基因表达外 ,还可通过诱导 MMP- 2表达而发挥其对细胞外基质代谢的调节作用及参与 VSMC迁移的启动过程 ;细胞因子对 VSMC MMP- 2基因表达的诱导作用是通过促进转录调控因子的合成或活化而实现的 .     

迷迭香酸对乳腺癌MDA-MB-231细胞增殖、凋亡和迁移能力的影响

研究迷迭香酸对乳腺癌MDA-MB-231细胞增殖、凋亡和迁移能力的影响。采用磺酰罗丹明B(SRB)法测定迷迭香酸对乳腺癌MDA-MB-231细胞增殖的影响,Hoechst 33258荧光染色法观察细胞凋亡形态,Annexin VFITC/PI检测细胞凋亡率;同时,细胞划痕实验检测迷迭香酸对MDA-MB-231细胞体外迁移能力的影响,实时荧光PCR(qPCR)法检测Bax、Bcl-2、Caspase-3、MMP-2和MMP-9基因的表达水平。研究结果显示迷迭香酸能抑制乳腺癌MDA-MB-231细胞的增殖,且呈时间剂量依赖性;迷迭香酸处理后的MDA-MB-231细胞出现明显的凋亡形态,且细胞凋亡率明显增加,Bax和caspase-3 mRNA表达水平增加,而Bcl-2 mRNA表达水平降低。另外,迷迭香酸作用后可剂量依赖性地降低MDA-MB-231细胞的体外迁移能力;同时降低MMP-2和MMP-9 mRNA的表达。因此,迷迭香酸能有效的抑制MDA-MB-231细胞的增殖,诱导细胞凋亡,降低细胞迁移能力。     

nAChRα1调控尼古丁促进巨噬细胞RAW264.7增殖迁移的作用研究

目的:探讨nAChRα1是否参与调节尼古丁促进巨噬细胞RAW264.7增殖迁移的作用。方法:将体外培养的RAW264.7细胞分4组为:(1)正常对照组;(2)尼古丁组;(3)对照干扰+尼古丁组;(4)nAChRα1干扰+尼古丁组。用尼古丁(5 ng/mL)刺激巨噬细胞RAW264.7,特异性nAChRα1 si RNA用脂质体3000转染细胞,CCK-8法检测尼古丁处理3 h、24 h和48 h后细胞的增殖情况,细胞划痕实验检测细胞迁移情况,Western blot和RT-PCR检测细胞内nAChRα1、MMP-2、MMP-9的蛋白和mRNA的表达情况。结果:与空白对照组相比,尼古丁可显著促进RAW264.7细胞的增殖和迁移,增加nAChRα1、MMP-2、MMP-9的蛋白和mRNA表达;而在干扰nAChRα1表达后,尼古丁诱导的RAW264.7细胞的增殖和迁移明显被抑制,且细胞nAChRα1、MMP-2、MMP-9的蛋白和mRNA表达均显著的降低。结论:nAChRα1可介导尼古丁促进RAW264.7细胞的增殖和迁移,这可能与其参与调控尼古丁增加RAW264.7细胞分泌MMP-2、MMP-9有关。     

黄芪皂苷Ⅳ对LPS诱导大鼠心肌损伤的保护作用及机制

目的:研究黄芪皂苷Ⅳ对LPS诱导的大鼠心肌损伤的保护作用及机制.方法:心肌细胞的活力,乳酸脱氢酶(LDH)的释放,肌酸激酶(CK)的含量被测量来判断心肌细胞损伤的程度.对超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、肿瘤坏死因子-α(TNF-α)的释放以及Sirt1的蛋白表达进行评估.结果:1,3和10 μM黄芪皂苷Ⅳ可显著降低LPS诱导的心肌细胞LDH,CK和MDA的生成;黄芪皂苷Ⅳ可剂量依赖性地增加SOD的活性,减少TNF-α的释放.黄芪皂苷Ⅳ的干预可剂量依赖性的增加由LPS刺激而引起的乳鼠心肌细胞Sirt1蛋白的表达.结论:结果表明,黄芪皂苷Ⅳ可通过调控氧化应激和Sirt1-TNF-α途径有效发挥对LPS诱导大鼠心肌损伤的保护作用.     

黄芪甲苷Ⅳ对内毒素诱导RAW264.7细胞损伤的保护作用及机制研究

目的:研究黄芪皂苷Ⅳ对LPS诱导的巨噬细胞RAW264.7损伤的保护作用及机制.方法:测定细胞活力判断心肌细胞损伤的程度.TNF-α,IL-1β,IL-6,IL-10的释放以及NF-кB蛋白、Akt和磷酸化Akt表达用以研究作用机制.结果:黄芪皂苷Ⅳ对LPS引起的RAW264.7细胞损伤具有显著的抑制作用,1,3和10μM黄芪皂苷Ⅳ可显著降低LPS诱导的RAW264.7细胞TNF-α,IL-1β和IL-6的生成,促进IL-10的释放.黄芪皂苷Ⅳ剂量依赖性地增加了由LPS刺激而引起的RAW264.7细胞NF-kB蛋白的表达,抑制了LPS所致的p-Akt蛋白表达的升高.结论:黄芪皂苷Ⅳ可通过Akt-NF-kB途径调控促炎因子和抗炎因子表达的失衡,有效发挥对LPS诱导巨噬细胞RAW264.7损伤的保护作用.     

水飞蓟宾对人肝癌HepG2细胞迁移的作用研究

目的观察水飞蓟宾对人肝癌(HCC)HepG2细胞迁移的作用。方法采用MTT法观察水飞蓟宾对HepG2细胞的增殖抑制作用,采用细胞划痕实验和Transwell小室法观察水飞蓟宾对HepG2细胞迁移的作用,通过RT-PCR方法检测迁移相关基因Twist、Snail和Slug的表达水平;采用单因素方差分析方法比较不同浓度水飞蓟宾对细胞活力、细胞迁移距离的和迁移细胞个数的影响,并比较各组间Twist、Snail和Slug的转率。结果 MTT检测结果显示不同浓度(0,30,60,120,240,480μg/ml)水飞蓟宾可以不同程度地抑制HepG2细胞增殖,同时呈现剂量依赖和时间依赖(P0.05);与对照组相比,HepG2细胞在划痕24 h后,水飞蓟宾组(60,120,240μg/ml)的迁移距离分别为(1.50±0.24)cm(P=0.046)、(1.20±0.33)cm(P=0.037)和(1.05±0.24)cm(P=0.029);Transwell实验中水飞蓟宾组(60,120和240μg/ml)细胞迁移个数分别为(100.00±4.25)个、(30.00±5.34)个和(6.00±2.28)个(P均0.05);PCR结果显示,水飞蓟宾不同程度的降低HepG2细胞Snail、Slug和Twist基因的转率。结论水飞蓟宾可抑制人HCC HepG2细胞的迁移。     

在寻常型银屑病中HBD-2、MMP-9及TNF-α的表达与PASI评分的正相关关系

为了探讨寻常型银屑病患者皮损中β-防御素2(HBD-2)、基质金属蛋白酶9(MMP-9)、肿瘤坏死因子-α(TNF-α)蛋白的表达情况及其临床意义。本研究选取在我院2014年8月至2016年12月皮肤科确诊的寻常型银屑病患者90例作为病例组,另选30例健康对象作为健康组,分别采用免疫组化检测两组HBD-2、MMP-9、TNF-ɑ蛋白的表达,分析其与患者银屑病皮疹面积和严重程度评分法(PASI)评分的关系。研究发现,病例组患者皮损中HBD-2、MMP-9、TNF-α蛋白光密度值显著的高于健康组皮肤,并且MMP-9指标最大;根据PASI将银屑病患者分组,皮损中HBD-2、MMP-9、TNF-α蛋白光密度值组间比较为轻度组中度组重度组,差异均具有统计学意义(p0.05)。因此,银屑病患者皮损中HBD-2、MMP-9、TNF-α蛋白光密度值与PASI评分均呈显著的正相关关系,HBD-2、MMP-9、TNF-α的表达水平可以作为辅助临床诊断和治疗寻常型银屑病的判断指标,也为进一步探究寻常型银屑病发病机制提供参考依据。     

钙周期素结合蛋白促进胃癌细胞迁移侵袭和MMP-2、MMP-9、p-ERK1/2、p-AKT水平上调

目的探讨钙周期素结合蛋白(calcyclin binding protein/Siah-1-interacting protein, CacyBP/SIP)对胃癌细胞侵袭迁移的影响和潜在机制。方法采用免疫组织化学和Western blot方法检测不同T分期胃癌组织中CacyBP/SIP水平;Western blot检测胃癌细胞中CacyBP/SIP水平;MKN-45细胞转染si-CacyBP/SIP与Ad-CacyBP/SIP后,细胞划痕实验检测细胞迁移情况,Transwell细胞侵袭实验检测细胞侵袭情况,Western blot检测MMP-2、MMP-9和p-ERK1/2、p-AKT水平。结果 CacyBP/SIP在胃癌组织和胃癌细胞中高表达;胃癌组织中CacyBP/SIP表达水平与T分期呈正相关;敲减CacyBP/SIP抑制MKN-45细胞的迁移侵袭能力和MMP-2、MMP-9、p-ERK1/2、p-AKT蛋白表达水平;过表达CacyBP/SIP促进MKN-45细胞迁移侵袭能力和MMP-2、MMP-9、p-ERK1/2、p-AKT蛋白表达水平。结论 CacyBP/SIP对胃癌转移侵袭能力的促进作用可能与其上调MMP-2、MMP-9、p-ERK1/2、p-AKT水平有关。     

Suppression of TNF-alpha-induced MMP-9 expression by a cell-permeable superoxide dismutase in keratinocytes

Up-regulation of selected matrix metalloproteinases (MMPs) such as MMP-9 contributes to inflammatory processes during the development of various skin diseases, such as atopic dermatitis. In this study, we examined the effect of a cell-permeable superoxide dismutase (Tat-SOD) on TNF-α-induced MMP-9 expression in human keratinocyte cells (HaCaT). When Tat-SOD was added to the culture medium of HaCaT cells, it rapidly entered the cells in dose- and time-dependent manners. Tat-SOD decreased TNF-α-induced reactive oxygen species (ROS) generation. Tat-SOD also inhibited TNF-α-induced NF-κB DNA binding activity. Treatment of HaCaT cells with Tat-SOD significantly inhibited TNF-α-induced mRNA and protein expression of MMP-9, as measured by RT-PCR and Western blot analysis. In addition, Tat-SOD suppressed TNF-α-induced gelatinolytic activity of MMP-9. Taken together, our results indicate that Tat-SOD can suppress TNF-α-induced MMP-9 expression via ROS-NF-κB-dependent mechanisms in keratinocytes, and therefore can be used as an immunomodulatory agent against inflammatory skin diseases related to oxidative stress.     

Silibinin prevents TPA-induced MMP-9 expression and VEGF secretion by inactivation of the Raf/MEK/ERK pathway in MCF-7 human breast cancer cells

Matrix metalloproteinase-9 (MMP-9) and vascular endothelial growth factor (VEGF) expression are pivotal steps in cancer metastasis. Herein, we investigated the effect of silibinin, a major constituent (flavanolignan) of the fruits of Silybum marianum, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 and VEGF expression in MCF-7 human breast cancer cells. The expression of MMP-9 and VEGF in response to TPA was increased, whereas TPA-induced MMP-9 and VEGF expression was decreased by silibinin. To investigate the regulatory mechanism of silibinin on TPA-induced MMP-9 and VEGF expression, we pretreated cells with various inhibitors, such as UO126 (MEK1/2 inhibitor), SP600125 (JNK inhibitor), and SB203580 (p38 inhibitor). Interestingly, TPA-induced MMP-9 expression was significantly inhibited by UO126, but not by SP600125 and SB203580. In addition, we pretreated cells with 100 μM silibinin prior to TPA treatment. TPA-induced MEK and ERK phosphorylation was significantly decreased by silibinin in MCF7 cells. TPA-induced VEGF expression was also suppressed by UO126. On the other hand, we found that adenoviral constitutive active-MEK (Ad-CA-MEK) significantly increased MMP-9 and VEGF expression. Taken together, we suggest that the inhibition of TPA-induced MMP-9 and VEGF expression by silibinin is mediated by the suppression of the Raf/MEK/ERK pathway in MCF-7 breast cancer cells.     

Eicosapentaenoic acid inhibits TNF-alpha-induced matrix metalloproteinase-9 expression in human keratinocytes, HaCaT cells

Eicosapentaenoic acid (EPA) is an omega-3 (ω-3) polyunsaturated fatty acid (PUFA), which has anti-inflammatory and anti-cancer properties. Some reports have demonstrated that EPA inhibits NF-κB activation induced by tumor necrosis factor (TNF)-α or lipopolysaccharide (LPS) in various cells. However, its detailed mode of action is unclear. In this report, we investigated whether EPA inhibits the expression of TNF-α-induced matrix metalloproteinases (MMP)-9 in human immortalized keratinocytes (HaCaT). TNF-α induced MMP-9 expression by NF-κB-dependent pathway. Pretreatment of EPA inhibited TNF-α-induced MMP-9 expression and p65 phosphorylation. However, EPA could not affect IκB-α phosphorylation, nuclear translocation of p65, and DNA binding activity of NF-κB. EPA inhibited TNF-α-induced p65 phosphorylation through p38 and Akt inhibition and this inhibition was IKKα-dependent event. Taken together, we demonstrate that EPA inhibits TNF-α-induced MMP-9 expression through inhibition of p38 and Akt activation.     

TNF-α promotes human retinal pigment epithelial (RPE) cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression through activation of Akt/mTORC1 signaling

Tumor necrosis factor-alpha (TNF-α) promotes in vitro retinal pigment epithelial (RPE) cell migration to initiate proliferative vitreoretinopathy (PVR). Here we report that TNF-α promotes human RPE cell migration by inducing matrix metallopeptidase 9 (MMP-9) expression. Inhibition of MMP-9 by its inhibitor or its neutralizing antibody inhibited TNF-α-induced in vitro RPE cell migration. Reversely, exogenously-added active MMP-9 promoted RPE cell migration. Suppression Akt/mTOR complex 1(mTORC1) activation by LY 294002 and rapamycin inhibited TNF-α-mediated MMP-9 expression. To introduce a constitutively active Akt (CA-Akt) in cultured RPE cells increased MMP-9 expression, and to block mTORC1 activation by rapamycin inhibited its effect. RNA interference (RNAi)-mediated silencing of SIN1, a key component of mTOR complex 2 (mTORC2), had no effect on MMP-9 expression or secretion. In conclusion, this study suggest that TNF-α promotes RPE cell migration by inducing MMP-9 expression through activation of Akt/ mTORC1, but not mTORC2 signaling.     

Aristolochic acid downregulates monocytic matrix metalloproteinase-9 by inhibiting nuclear factor-κB activation

Aristolochic acid (AA)-associated nephropathy was described as being characterized by a rapid progressive enhancement of interstitial renal fibrosis. Renal tissue fibrosis occurs because of an imbalance of extracellular matrix (ECM) accumulation and matrix metalloproteinase (MMP) activation. Much evidence indicates that inflammatory renal disease including monocyte and mesangial interactions is linked to the development and progression of renal remodeling. In this study, we found that AA showed concentration-dependent inhibition of tumor necrosis factor (TNF)-α-induced MMP-9 activation with an IC₅₀ value of 6.4 ± 0.5 μM in human monocytic THP-1 cells. A similar effect was also noted with different ratios of AAs (types I and II). However, AA had no inhibitory effect on the intact enzymatic activity of MMP-9 at a concentration of 20 μM. On the other hand, the level of tissue inhibitor of metalloproteinase (TIMP)-1 was not induced by AA, but it suppressed TNF-α-induced MMP-9 protein and messenger RNA expressions. AA also significantly inhibited TNF-α-induced IκBα degradation. Furthermore, an electrophoretic mobility shift assay and a reported gene study, respectively, revealed that AA inhibited TNF-α-induced NF-κB translocation and activation. In addition, compared to other NF-κB inhibitors, AA exerted significant inhibition of MMP-9 activation and monocyte chemotactic protein-1-directed invasion. From these results, we concluded that AA, a natural compound, inhibits TNF-α-induced MMP-9 in human monocytic cells possibly through the NF-κB signal pathway. These results also imply that AA may be involved in alteration of matrix homeostasis during renal fibrosis in vivo.