新型倍半萜Souliene A抑制小胶质细胞活化作用及机制

目的研究Souliene A对LPS与IFN-γ介导的小胶质细胞激活的抑制作用与机制及其对小胶质细胞激活引起的神经元损伤的保护作用。方法分别用LPS与IFN-γ刺激小鼠小胶质细胞BV2,Griess法测定NO。Western blotting和半定量RT-PCR法检测iNOS,COX-2,IL-6,IL-1β,TNF-α的表达及其相关信号通路。ELISA法检测PGE2和IL-6,IL-1β,TNF-α的表达。用流式细胞术检测小胶质细胞内ROS生成。用MTT法检测神经元细胞的存活率。结果 SoulieneA能明显抑制NO和PGE2的生成,减少炎症介质IL-6,IL-1β,TNF-α的表达,抑制小胶质细胞内ROS的产生。SoulieneA还能抑制NF-κB的活化与Akt的磷酸化并能有效的抑制小胶质细胞条件培养液引起的神经元损伤。     

百草枯对小胶质细胞TLR-4蛋白及TNF-α和IL-1β基因表达水平的影响

目的探讨百草枯(paraquat,PQ)对小胶质细胞TLR-4蛋白及TNF-α和IL-1β基因表达水平的影响,为进一步探究百草枯诱导小胶质细胞炎症反应可能的作用机制提供线索。方法小鼠小胶质(BV2)细胞分为PQ(40μmol/L)染毒组、LPS阳性对照组(1μg/ml)和阴性对照组,分别处理6、12和24 h。Western blotting法检测TLR-4蛋白表达,荧光定量PCR法检测TNF-α和IL-1β基因表达水平。结果 6、12和24 h,PQ染毒组、LPS阳性对照组小胶质细胞TLR-4蛋白表达水平、TNF-α和IL-1β基因表达水平均显著增加。结论 PQ能增加小胶质细胞TLR-4蛋白表达,进而可能激活TLR-4信号通路,使炎症因子表达增加,诱导炎症反应。     

LPS对BV2细胞TNF-α、CD11b和IL-1β表达的影响

目的 探讨脂多糖(LPS)对BV2细胞肿瘤坏死因子α(TNF-α)、簇分化抗原11b(CD11b)和白细胞介素1β(IL-1β)表达的影响.方法 分别用LPS 0、1、10、100μg/ml和LPS 10μg/ml 以0、2、4、8、12、24h刺激BV2细胞,ELISA法检测细胞培养上清液中分泌的TNF-α表达量,RT-PCR 检测CD11b及IL-1β mRNA表达变化.结果 用LPS 10μg/ml刺激BV2细胞4h后,上清液中TNF-α的释放量达到峰值,同时CD11b及IL-1β mRNA表达明显增加.结论 LPS能促进BV2细胞高效表达CD11b、IL-1β和分泌TNF-α,从而为BV2细胞作为免疫活性细胞在中枢神经系统中发挥免疫调节作用提供依据.     

红景天苷调控PI3K/Akt信号通路对LPS诱导的BV2小胶质细胞的抗炎作用

目的探讨红景天苷对脂多糖(LPS)诱导的BV2小胶质细胞的抗炎作用及其机制。方法建立LPS诱导BV2小胶质细胞损伤模型。经不同浓度的红景天苷作用后,q PCR法检测细胞因子IL-6、IL-1β、TNF-αmRNA的表达; Western blot法检测Akt、p-Akt、核蛋白NF-κB p50的蛋白表达。PI3K抑制剂LY294002作用30 min,再经红景天苷作用后,检测Akt、p-Akt、核蛋白NF-κB p50、IL-6、IL-1β、TNF-α等指标。结果与模型组比较,红景天苷能够抑制BV2小胶质细胞IL-6、IL-1β、TNF-αmRNA的表达,促进p-Akt蛋白表达,抑制核蛋白NF-κB p50;经LY294002作用后,红景天苷对pAkt、核蛋白NF-κB p50、IL-6、IL-1β等作用不明显。结论红景天苷能够抑制LPS诱导的BV2小胶质细胞炎症反应,主要是通过激活PI3K/Akt信号通路,促进Akt的磷酸化,抑制NF-κB p50核转录,进而抑制细胞因子。     

米诺环素对脂多糖诱导的肺微血管内皮细胞炎症损伤的抑制作用

目的探讨米诺环素对急性肺损伤肺微血管内皮细胞炎症损伤的抑制作用。方法以脂多糖(LPS)10 mg·L^-1与肺微血管内皮细胞作用24 h,构建炎症损伤的细胞模型;米诺环素10和25μmol·L^-1共孵育24 h,用CCK-8法检测细胞存活率,ELISA检测培养液中肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)、IL-8和细胞间黏附分子1(ICAM-1)水平,流式细胞术分析细胞活性氧(ROS)水平,Western印迹法检测细胞聚腺苷二磷酸核糖聚合酶1(PARP-1)和NF-κB表达。结果米诺环素可保护LPS诱导的肺微血管内皮细胞炎症损伤,LPS组细胞存活率为82.4%,米诺环素10和25μmol·L^-1组细胞存活率可达90.6%和96.9%(P<0.01)。米诺环素可降低LPS诱导的肺微血管内皮细胞炎症因子的表达,与LPS组相比,米诺环素组细胞TNF-α,IL-6,IL-8和ICAM-1的表达显著降低(P<0.01)。米诺环素还显著抑制LPS诱导的细胞氧化应激,LPS组细胞ROS相对水平为3.19,米诺环...     

石菖蒲抑制脂多糖诱导的神经胶质细胞炎性反应及其机制

目的 观察石菖蒲对脂多糖(lipopolysaccharide,LPS)诱导的大鼠原代神经胶质细胞炎性反应的抑制作用并探讨其可能机制.方法 分离提取大鼠原代神经胶质细胞,用LPS刺激2h后分别加入不同浓度的石菖蒲含药血清,采用硝酸还原酶法检测石菖蒲对一氧化氮的影响,运用酶联免疫吸附法(ELISA)测定培养上清液中IL-1 β、IL-8、TNF-α水平,通过实时逆转录聚合酶链反应(RT-PCR)测定细胞中诱导型一氧化氮合酶(iNOS) mRNA表达.结果 LPS能够激活神经胶质细胞,不同浓度的石菖蒲含药大鼠血清在不影响细胞存活率的情况下,可以显著降低细胞培养上清液中NO、IL-1β、IL-8、TNF-α水平,抑制细胞内iNOS mRNA表达(P＜0.05).结论 石菖蒲的神经保护机制可能与抑制胶质细胞炎症反应有关.     

金钗石斛多糖对脂多糖作用大鼠皮层胶质细胞-神经元体系的保护作用

目的观察金钗石斛多糖(NDP)对脂多糖(LPS)作用的新生大鼠大脑皮层胶质细胞-神经元混合培养体系的保护作用。方法原代制备新生大鼠大脑皮层胶质细胞-神经元混合培养体系,NDP作用于LPS刺激的胶质细胞-神经元混合培养体系,观察细胞生长情况,并采用Real time PCR法检测体系中炎症相关因子IL-1β、TNF-α、COX-2的基因表达。结果 NDP作用于LPS刺激的大鼠皮层胶质细胞-神经元混合培养体系后,胶质细胞激活减少、神经元损伤减轻,较单用LPS作用的模型组相比,炎症相关因子IL-1β、TNF-α、COX-2的基因表达明显降低。结论 NDP能抑制LPS对小胶质细胞和星形胶质细胞的激活,减少炎性因子的生成。     

吡格列酮对脂多糖诱导的星形胶质细胞炎性细胞因子释放的影响

目的研究吡格列酮对脂多糖(LPS)诱导的星形胶质细胞炎症介质释放的抑制作用及其信号传导通路。方法神经胶质酸性蛋白(glial fibrillary acid protein,GFAP)免疫荧光染色法鉴定星形胶质细胞纯度。ELISA方法检测IL-1β、IL-6和TNF-α蛋白表达量的变化。Griess法测定培养细胞上清液中一氧化氮(NO)含量。结果星形胶质细胞经GFAP免疫荧光鉴定,其阳性率可达95%以上。LPS组能明显增加星形胶质细胞分泌IL-1β、IL-6、TNF-α及NO。吡格列酮能明显抑制LPS引起的这些作用,并呈一定浓度依赖性。过氧化物酶体增殖物激活受体γ(PPARγ)的特异性阻断剂GW9662能明显对抗吡格列酮对LPS引起的IL-1β、IL-6、TNF-α及NO增加的抑制作用。与LPS组相比,JNK特异性阻断剂SP600125(5μmol·L-1)亦能有效对抗LPS诱导星形胶质细胞IL-1β、IL-6、TNF-α及NO分泌的增加;特异性iNOS抑制剂SMT可明显抑制LPS引起的NO分泌增加。结论吡格列酮能明显改善LPS诱导的大鼠皮层星形胶质细胞的损伤,这种作用可能与激活PPARγ、抑制JNK信号传导通路有关。     

小胶质细胞抑制剂对佐剂性关节炎大鼠脊髓促炎性细胞因子的影响

目的:观察小胶质细胞抑制剂对佐剂性关节炎大鼠脊髓促炎性细胞因子的影响。方法:蛛网膜下腔置管成功的雄性SD大鼠分别脊髓蛛网膜下腔注射(it)生理盐水(NS)和米诺环素50μg,30 min后右踝关节皮内注射完全氟氏佐剂(CFA),it,qd,连续7 d,观察CFA后0,2,6,13 d后爪热刺激回缩潜伏期(PWTL)的变化及CFA致炎后0,2,6 d给药后4 h和13 d脊髓IL-1β,IL-6,TNF-α含量变化,这些促炎性细胞因子的表达水平通过ELISA方法检测。结果:米诺环素能抑制PTWL缩短;CFA致炎后脊髓IL-1β,IL-6,TNF-α表达明显增加,米诺环素可减少相应时间点脊髓IL-1β,IL-6,TNF-α的表达水平。结论:蛛网膜下腔注射米诺环素可以减少外周炎症诱导的脊髓促炎性细胞因子的分泌;脊髓小胶质细胞可能通过促炎性细胞因子介导炎性痛觉过敏。     

绿原酸抑制NF-κB/NLRP3炎性体通路减轻LPS诱导小胶质细胞神经炎症损伤研究

摘要：目的:探究绿原酸（CGA）对脂多糖（LPS）诱导的小胶质细胞神经炎症损伤及核因子κB（NF-κB）/Nod样受体家族含pyrin结构域蛋白3（NLRP3）炎性体通路的影响。方法:培养小胶质细胞BV2,3-（4,5-二甲基噻唑-2）-2,5-二苯基四氮唑溴盐（MTT）法检测不同浓度(0,1,2,4,8 mmol·L-1)CGA对BV2细胞活力的影响;再次培养BV2细胞,依次分为对照（Control）组、LPS组、脂多糖和药物溶剂对照[LPS+二甲亚砜（DMSO）]、脂多糖和阳性药物对照（LPS+Positive）组以及脂多糖和绿原酸处理（LPS+CGA）组。免疫荧光法检测肿瘤坏死因子α（TNF-α）和白细胞介素（IL）-1β表达情况;ELISA法检测TNF-α、IL-1β、IL-6、IL-10、IL-12和诱导型一氧化氮合成酶（iNOS）含量;免疫印迹分析NF-κB/NLRP3炎性体通路和凋亡相关蛋白水平;流式细胞仪检测细胞凋亡率。结果:与CGA 0 mmol·L-1比较,CGA 1,2,4 mmol·L-1对BV2细胞增殖活力的影响无统计学意义（P>0.05）,CGA 8 mmol·L-1显著降低BV2细胞增殖活力（P<0.05）。LPS诱导后细胞凋亡率升高,细胞上清液中TNF-α、IL-1β、IL-6、IL-12和iNOS分泌量增多,IL-10分泌量减少,细胞中NF-κB p65、磷酸化NF-κB抑制蛋白（p-IκBα）、NLRP3、含半胱氨酸的天冬氨酸蛋白水解酶1（Caspase-1）和B细胞淋巴瘤/白血病-2（Bcl-2）相关X蛋白（Bax）蛋白水平上调,细胞中Bcl-2蛋白水平下调（P<0.05）。添加CGA可明显改善LPS对BV2细胞的影响（P<0.05）。结论:CGA通过抑制NF-κB/NLRP3炎性体通路减轻LPS诱导的BV2细胞神经炎症损伤。     

Inhibitory action of minocycline on lipopolysaccharide-lnduced release of nitric oxide and prostaglandin E2 in BV2 microglial cells

Microglia are the major inflammatory cells in the central nervous system and become activated in response to brain injuries such as ischemia, trauma, and neurodegenerative diseases including Alzheimer's disease (AD). Moreover, activated microglia are known to release a variety of proinflammatory cytokines and oxidants such as nitric oxide (NO). Minocycline is a semisynthetic second-generation tetracycline that exerts anti-inflammatory effects that are completely distinct form its antimicrobial action. In this study, the inhibitory effects of minocycline on NO and prostaglandin E2 (PGE2) release was examined in lipopolysaccharides (LPS)-challenged BV2 murine microglial cells. Further, effects of minocycline on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression levels were also determined. The results showed that minocycline significantly inhibited NO and PGE2 production and iNOS and COX-2 expression in BV2 microglial cells. These findings suggest that minocycline should be evaluated as potential therapeutic agent for various pathological conditions due to the excessive activation of microglia.     

脂质微泡介导转染MIF siRNA对小鼠急性肺损伤的保护作用

目的：通过探讨超声微泡基因转染系统转染MIF siRNA对小鼠急性肺损伤的保护作用,评价超声微泡基因转染系统的有效性。方法：以脂多糖（LPS）诱导小鼠建立急性肺损伤动物模型,随机分成4组：正常对照组（Con）、LPS刺激组（LPS）、LPS＋PC＋MIF siRNA治疗组（PC＋MIF siRNA）、LPS＋WP＋MIF siRNA治疗组（WP＋MIF siRNA）;通过超声微泡基因转染系统转染MIF siRNA,运用EMSA、Western-Blot、ELISA和相关病理检测技术,观察小鼠肺组织NF-κB/IκB-α表达、炎症介质TNF-α、IL-1β、IL-6水平,及肺组织湿干重比和炎症病理病变,探讨MIF siRNA对小鼠急性肺损伤的保护作用。结果：WP＋MIF siRNA治疗组通过上调肺组织细胞浆中IκB-α表达,对LPS刺激激活的细胞核NF-κB有明显抑制作用、从而抑制炎症介质TNF-α、IL-1β、IL-6释放,减轻小鼠肺组织病理损伤。但PC＋MIF siRNA治疗组对LPS刺激导致的小鼠肺损伤无任何改善的治疗作用。结论：脂质微泡/PEI-Chol介导的基因转染系统能有效转染MIF siRNA,对LPS介导的小鼠急性肺损伤具有一定的保护作用。     

Involvement of heme oxygenase-1 induction in the cytoprotective and immunomodulatory activities of 6,4'-dihydroxy-7-methoxyflavanone in murine hippocampal and microglia cells

6,4'-Dihydroxy-7-methoxyflavanone (DMF), a biologically active compound, was isolated from the heartwood of Dalbergia odorifera T. Chen (Leguminosae). The present study proposed to examine the role of DMF as an anti-oxidative and anti-inflammatory heme oxygenase-1 (HO-1) inducer in mouse hippocampal HT22 cells and BV2 microglia cells. The effect of DMF on cell viability was determined by MTT assay and the effects of DMF on pro-inflammatory enzymes and cytokines were analyzed by western blot and ELISA. Parameters such as DMF induced HO-1 protein immunocontents, HO activity and mitogen-activated protein kinases (MAPK) activation were also measured. DMF increased cellular resistance to oxidative injury caused by glutamate-induced cytotoxicity in HT22 cells, via JUN N-terminal kinase (JNK) pathway dependent HO-1 expression. Furthermore, DMF suppressed the lipopolysaccharide (LPS)-induced expression of pro-inflammatory enzymes and inflammatory mediators in BV2 microglia. DMF suppressed production of nitric oxide (NO), prostaglandin E2 (PGE(2)), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), through extracellular signal-regulated kinase (ERK) pathway dependent HO-1 expression. This study indicates that DMF effectively modulates the regulation of anti-oxidative and anti-inflammatory action, via up-regulation of HO-1 in HT22 cells and BV2 microglia. These results suggest that DMF possesses therapeutic potentials against neurodegenerative diseases that are induced by oxidative stress and neuroinflammation.     

Phlorofucofuroeckol B suppresses inflammatory responses by down-regulating nuclear factor κB activation via Akt,ERK, and JNK in LPS-stimulated microglial cells

Microglial activation has been implicated in many neurological disorders for its inflammatory and neurotrophic effects. In this study, we investigated the effects of phlorofucofuroeckol B (PFF-B) isolated from Ecklonia stolonifera, on the production of inflammatory mediators in lipopolysaccharide (LPS)-stimulated microglia. PFF-B decreased secretion of pro-inflammatory cytokines including tumor necrosis factor α, interleukin (IL)-1β, and IL-6 and the expression of pro-inflammatory proteins such as cyclooxygenase-2 and inducible nitric oxide synthase in LPS-stimulated BV-2 cells. Profoundly, PFF-B inhibited activation of nuclear factor kappaB (NF-κB) by preventing the degradation of inhibitor κB-α (IκB-α), which led to prevent the nuclear translocation of p65 NF-κB subunit. Moreover, PFF-B inhibited the phosphorylation of Akt, ERK, and JNK. These results indicate that the anti-inflammatory effect of PFF-B on LPS-stimulated microglial cells is mainly regulated by the inhibition of IκB-α/NF-κB and Akt/ERK/JNK pathways. Our study suggests that PFF-B can be considered as a therapeutic agent against neuroinflammation by inhibiting microglial activation.     

Inhibition of gene expression and production of iNOS and TNF-alpha in LPS-stimulated microglia by methanol extract of Phellodendri cortex

Activation of microglia has been increasingly associated with the pathogenesis of several neurodegenerative disorders including Parkinson's and Alzheimer's diseases, and the suppression of microglial activation may lead to alleviation of the progression of neurodegeneration in these diseases. We sought to investigate whether Phellodendri cortex (PC) that has been used for centuries in Chinese traditional medicine for the treatment of various inflammatory conditions, inhibits production of anti-inflammatory cytokines and nitric oxide (NO) in microglia, and further studied the molecular and cellular mechanisms that govern these anti-inflammatory effects. The methanol extract of PC (PC extract) attenuated LPS-stimulated increase in production of TNF-alpha, IL-1beta, and NO in BV2 cells, a mouse microglia cell line, as well as in primary mouse microglia. The RNase protection assay and RT-PCR revealed that the PC extracts inhibited increases in mRNAs of these cytokines and iNOS in LPS-stimulated BV2 cells. The PC extracts significantly decreased release of these cytokines and NO from LPS-stimulated microglia in a dose-dependent manner. Molecular mechanisms that govern attenuation of the levels of mRNAs and proteins of these cytokines and iNOS revealed that the PC extract inhibited LPS-stimulated phosphorylation of ERK and activation of NF-kappaB. The studies demonstrate that the PC extract effectively inhibits microglial production and release of inflammatory cytokines and NO, and could be a candidate agent for anti-inflammation in neurodegenerative human brain diseases.     

乌帕替尼对氧糖剥夺/复氧后BV2细胞极化的影响

目的 研究乌帕替尼对氧糖剥夺再复氧(OGD/R)后BV2小胶质细胞极化及炎症的影响,并探讨其作用机制.方法 实验分对照组、OGD组和乌帕替尼组3组.BV2细胞经OGD/R处理后,噻唑蓝试剂(MTT)检测细胞生存率,划痕实验观察细胞迁移能力,实时荧光定量多聚核苷酸链式反应(qPCR)检测BV2细胞M1型极化标志物(CD1...     

Anti-neuroinflammatory effects of tannic acid against lipopolysaccharide-induced BV2 microglial cells via inhibition of NF-κB activation

Microglia mediated neuroinflammation is known to cause various neurodegenerative and neurological ailments. Tannic acid is a natural polyphenol which has been reported to possess antioxidant, anti-inflammatory, anticarcinogenic, antimutagenic, antitumor, and antimicrobial activities. As there are no reports till date on the anti-neuroinflammatory effects of tannic acid, this study was conducted to analyze the possible mechanism and pathway involved in the prevention of neuroinflammation by tannic acid in BV2 microglial cells. BV2 microglial cells were pretreated with tannic acid (10, 25, and 50 μM/mL) and induced with lipopolysaccharide (LPS; 1 μM/mL) to assess the production of reactive oxygen species (ROS), nitric oxide (NO), prostaglandin E2 (PGE2), pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α), and nuclear factor-kappa B (NF-κB) protein expressions through western blotting. The results showed that LPS significantly activated the BV2 cells via toll-like receptor 4 to induce elevated productions of ROS, NO, PGE2, IL-6, and IL-1β. However, tannic acid was able to reverse all the neuroinflammatory effects of LPS-induced BV2 cells in a dose-dependent manner. Collectively, the anti-inflammatory effects of tannic acid on LPS-induced BV2 microglial cells are attributed to the inhibition of ROS formation and the suppression of NF-κB pathway activation. Tannic acid could be a potential therapeutic agent for the treatment of neurological related disorders.     

Involvement of mTOR kinase in cytokine-dependent microglial activation and cell proliferation

Neuroinflammation plays a prominent role in the pathophysiology of several neurodegenerative disorders, including Multiple Sclerosis. Reactive microglial cells are always found in areas of active demyelination as well as in normal-appearing white matter. Microglia contribute to initiating and maintaining brain inflammation, and once activated release pro-inflammatory mediators potentially cytotoxic, like nitric oxide (NO). It is now evident that the mTOR signaling pathway regulates different functions in the innate immune system, contributing to macrophage activation. More recently, mTOR has been found to enhance the survival of EOC2 microglia during oxygen-glucose deprivation and increase NO synthase 2 (NOS2) expression during hypoxia in BV2 microglial cell line, thus suggesting an involvement in microglial pro-inflammatory activation. In the present study, we detected mTOR activation in response to two different stimuli, namely LPS and a mixture of cytokines, in primary cultures of rat cortical microglia. Moreover, mTOR inhibitors reduced NOS activity and NOS2 expression induced by cytokines, but not those induced by LPS. The mTOR inhibitor RAD001, in combination with cytokines, also reduced microglial proliferation and the intracellular levels of cyclooxygenase. Under basal conditions mTOR inhibition significantly reduced microglial viability. Interestingly, mTOR inhibitors did not display any relevant effect on astrocyte NOS2 activity or cell viability. In conclusion, mTOR selectively controls microglial activation in response to pro-inflammatory cytokines and appears to play a crucial role in microglial viability; thus these drugs may be a useful pharmacological tool to reduce neuroinflammation.