苦参碱对oxLDL 诱导的血管平滑肌细胞炎症反应及增殖凋亡的影响及分子机制研究

目的:探讨苦参碱对氧化型低密度脂蛋白(oxLDL)诱导的血管平滑肌细胞炎症反应及增殖凋亡的影响及分子机制。方法:oxLDL 处理人主动脉血管平滑肌细胞建立动脉粥样硬化模型。CCK-8 实验分析细胞活力和增殖。实时定量PCR(qRT-PCR)检测炎症因子白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)、IL-10 和IL-13 的mRNA 水平。流式细胞术分析细胞凋亡。蛋白印迹检测增殖标记蛋白细胞增殖核抗原-67(Ki-67)和增殖细胞核抗原(PCNA),细胞凋亡标记蛋白B 细胞淋巴瘤-2(Bcl-2) 和Bcl-2 相关蛋白X(Bax),信号转导及转录激活子3(STAT3)和信号转导及转录激活子5(STAT5)的表达。结果:与对照组相比,造模组促炎因子IL-1β和TNF-α的mRNA 水平大大提高,抗炎因子IL-10 和IL-13 mRNA 水平则显著降低(P<0.01)。与造模组相比,模型加药组促炎因子IL-1β和TNF-α的mRNA 水平显著降低,抗炎因子IL-10 和IL-13 的mRNA 水平明显升高(P<0.05)。造模组细胞增殖倍数和细胞凋亡率明显高于对照组,模型加药组细胞增殖倍数和细胞凋亡率明显低于造模组(P<0.05)。与对照组相比,造模组Ki-67、PCNA 和Bax 的表达显著升高,Bcl-2 显著降低(P<0.01)。与造模组相比,模型加药组Ki-67、PCNA 和Bax 的表达明显减少,Bcl-2 表达明显增多(P<0.05)。造模组p-STAT3 和p-STAT5 相对蛋白表达量显著高于对照组(P<0.01)。模型加药组p-STAT3 和p-STAT5 相对蛋白表达量明显低于造模组(P<0.05)。与造模组相比,模型加药组和模型+Ruxolitinib 组Ki-67、PCNA 和Bax 的表达明显减少,Bcl-2 表达明显增多(P<0.05);模型加药+Ruxolitinib 组Ki-67、PCNA 和Bax 的表达显著减少,Bcl-2 表达显著增多(P <0.01)。与造模组相比,模型加药组和模型+Ruxolitinib 组及模型加药+Ruxolitinib 组IL-1β和TNF-α的mRNA 水平都明显降低,IL-10 和IL-13 的mRNA 水平都明显升高(P<0.05)。结论:苦参碱可通过抑制JAK/ STAT3 通路的活化起到抗炎和抑制血管平滑肌细胞增殖和凋亡的作用。     

石杉碱甲的抗炎作用及其对大鼠神经干细胞的保护作用

 目的： 探讨石杉碱甲（HupA）的抗炎作用及其对大鼠神经干细胞的保护作用。方法：取新生SD大鼠海马组织,分离并培养神经干细胞和小胶质细胞,建立Transwell共培养体系。将细胞分成3组：空白对照组、淀粉样β肽（Aβ）组和HupA组。Aβ组小胶质细胞层中加入终浓度为10 μmol/L的Aβ1-42,HupA组于加入Aβ1-42前4 h用1 μmol/L HupA预处理小胶质细胞。液相芯片技术检测炎症因子白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）和巨噬细胞炎症蛋白1α（MIP-1α）的表达,流式细胞术和Western blotting检测神经干细胞的凋亡。结果：小胶质细胞与神经干细胞共培养72 h后,与空白对照组相比,Aβ组IL-6、TNF-α和MIP-1α水平以及神经干细胞凋亡率（25.46%）均显著升高(P<0.01);HupA预处理小胶质细胞后,Aβ诱导的小胶质细胞炎症因子分泌显著减少,IL-6、TNF-α和MIP-1α的水平降低(P<0.01),同时神经干细胞凋亡率降低至8.05% (P<0.01)。Western blotting检测结果显示,HupA组Bcl-2/Bax值显著高于Aβ组(P<0.05)。结论：石杉碱甲可以抑制小胶质细胞分泌细胞因子和趋化因子,减弱Aβ诱导的炎症反应,降低神经干细胞凋亡率,从而发挥抗炎和神经保护作用。     

抑制或过表达GRK5 基因对星形胶质细胞凋亡及IL-1β和TNF-α表达的影响

目的:探讨抑制或过表达G 蛋白偶联受体激酶5(GRK5)基因对星形胶质细胞(AS)凋亡及IL-1β和TNF-α 表达的影响。方法:培养原代AS,将干扰GRK5 表达的siRNA(GRK5-siRNA)及GRK5 的过表达质粒(pcDNA3.1-GRK5)分别转染AS,通过Western blot 检测转染24 h 后的细胞中GRK5 蛋白的表达;缺氧处理AS,细胞分为空白组、缺氧组、缺氧+pcDNA3.1-GRK5 组和缺氧+GRK5-siRNA 组,缺氧处理24 h 后通过流式细胞仪检测各组细胞的凋亡率及ROS 含量;RT-PCR检测IL-1β和TNF-α的mRNA 表达;Western blot 检测p53、信号转导与转录因子3(STAT3)和p-STAT3 蛋白表达。结果:与空白组比较,转染GRK5-siRNA 的AS 中GRK5 的表达显著降低,转染pcDNA3.1-GRK5 的细胞GRK5 的表达显著升高(P <0.05);与空白组比较,缺氧组细胞凋亡率、ROS 水平及IL-1β、TNF-α、p53 和p-STAT3 的表达均显著升高(P<0.05);与缺氧组比较,缺氧+pcDNA3.1-GRK5 组细胞凋亡率、ROS 水平及IL-1β、TNF-α、p53 和p-STAT3 的表达均显著降低,缺氧+GRK5-siRNA组细胞凋亡率、ROS 水平及IL-1β、TNF-α、p53 和p-STAT3 的表达均显著升高(P<0.05)。结论:过表达GRK5 可降低AS 凋亡和ROS 水平,下调IL-1β、TNF-α、p53 表达及STAT3 信号通路,抑制GRK5表达反之。     

阿托伐他汀对TNF-α和IL-1β诱导的大鼠主动脉内皮细胞PAPP-A表达的影响

目的: 研究阿托伐他汀对炎症因子肿瘤坏死因子 α(TNF-α)和白细胞介素-1β(IL-1β)诱导大鼠主动脉内皮细胞表达妊娠相关血浆蛋白A(PAPP-A)的影响。方法: 原代培养大鼠主动脉内皮细胞,选择生长良好的第3-4代细胞用于实验。实验分组:(1)空白对照组 :不加干预措施原培养液继续培养;(2)阿托伐他汀浓度组:加入浓度分别为 0.1、1、10 μmol/L的阿托伐他汀作用24 h;(3)阿托伐他汀时间组:加入浓度为10 μmol/L的阿托伐他汀分别作用6、12、24 h;(4)阿托伐他汀干预组:加入TNF-α(60 μg/L)或者IL-1β(20 μg/L)作用1 h后,再加入不同浓度的阿托伐他汀(0.1、1、10 μmol/L)进行培养,分别于作用6、12、24 h终止实验。MTT法观察药物对细胞增殖的影响, RT-PCR技术测定细胞中PAPP-A mRNA的表达, ELISA方法检测上清液中PAPP-A蛋白水平。结果: (1) 外源性加入阿托伐他汀及TNF-α或者IL-1β后,分别作用3、6、12、24、48 h,同对照组相比,细胞增殖能力无明显变化(P<0.05),说明干预药物本身对细胞没有毒性作用。(2)单独加入阿托伐他汀,细胞PAPP-A表达水平与空白对照组比较没有明显差异(P<0.05)。(3)炎症因子作用一段时间后再加入阿托伐他汀,PAPP-A mRNA和蛋白表达水平随着阿托伐他汀浓度和作用时间的增加而逐渐降低,有一定的浓度-时间依赖关系,与 TNF-α组和IL-1β组比较明显下降(P<0.05)。结论: 阿托伐他汀本身对细胞表达PAPP-A没有影响,但在一定程度上抑制TNF-α和IL-1β诱导的内皮细胞PAPP-A的表达,并有浓度-时间依赖关系。     

胍丁胺通过细胞因子介导多器官功能衰竭小鼠保护作用的研究

目的:通过探讨胍丁胺(AGM)对炎症因子表达水平的影响,研究胍丁胺对酵母多糖(ZYM)诱导小鼠多器官功能衰竭(MODS)的保护作用。方法:小鼠腹腔注射ZYM+AGM,建立ZYM 诱导的炎症模型,同时设立空白组、AGM 组、ZYM组,观察各组建模前后小鼠进食、白细胞计数、心率等以确定造模是否成功。造模成功后对各组小鼠的肝功能、肾功能、心肌酶等生化指标进行检测;并通过qPCR 和ELISA 方法检测血液中肿瘤坏死因子(TNF-α)、白细胞介素1β(IL-1β)、白细胞介素6(IL-6)、IL-10 因子的基因和蛋白分泌水平。结果:注射ZYM 后的小鼠出现精神不振、活动和进食减少;检测小鼠各脏器功能血清学指标,显示脏器功能出现严重异常。与空白对照组相比,ZYM 组、ZYM+AGM 组小鼠血清学指标均明显增高;并伴随炎症因子TNF-α、IL1β、IL-6、IL-10 明显升高(P<0.05)。与ZYM 组相比,ZYM+AGM 组各脏器功能血清学指标降低,炎症因子TNF-α、IL-1β、IL-6 明显下降(P<0.05),IL-10 无明显差异(P>0.05),而小鼠精神、活动和进食等无明显的改变。结论:腹腔注射500 mg/ kg 的ZYM 能够成功构建小鼠MODS 模型,AGM 通过降低炎症因子的释放,对MODS 小鼠各器官功能起到一定的保护作用。     

聚腺苷二磷酸核糖糖苷水解酶调节癫痫大鼠海马组织凋亡诱导因子及炎症因子的研究

目的: 探讨聚腺苷二磷酸核糖糖苷水解酶(PARG)对癫痫大鼠海马神经元损伤的影响及其分子机制,探讨PARG抑制剂单宁酸对凋亡诱导因子(AIF)、白细胞介素1β(IL-1β)和肿瘤坏死因子α (TNF-α)的调节作用。方法: 应用Nissl染色方法检测海藻氨酸致痫大鼠海马神经元在单宁酸干预前后的变化;应用Western blotting检测单宁酸干预前后致痫大鼠海马组织聚腺苷二磷酸核糖、AIF、IL-1β和TNF-α表达的变化。结果: 单宁酸干预明显减少癫痫大鼠损伤海马神经元数目(P<0.05);增加致痫大鼠海马组织聚腺苷二磷酸核糖水平(P<0.05);增加致痫大鼠海马组织线粒体蛋白中AIF含量,降低核蛋白中AIF含量 (P<0.05);可显著降低致痫大鼠海马组织IL-1β和TNF-α蛋白表达(P<0.05)。结论: PARG抑制剂单宁酸可减轻癫痫大鼠海马神经元损伤,阻断线粒体AIF的核转位,抑制海马组织IL-1β和TNF-α的表达。     

白藜芦醇对氧糖剥夺/再复氧损伤后小胶质细胞系N9活化的影响

目的 探讨白藜芦醇对氧糖剥夺/再复氧损伤（OGD/R）后小胶质细胞系N9活化的影响。 方法 体外培养的N9小胶质细胞行氧糖剥夺150 min,复氧培养24 h。实验分为正常组（Nor）、对照组(Ctrl)和白藜芦醇预处理组(Res)。细胞计数盒-8（CCK-8）法测细胞活力,流式细胞仪检测细胞凋亡,免疫荧光法检测Iba1蛋白表达,Western blotting检测钙离子接头蛋白1（Iba1）、CD11b、Caspase-3、Bax、白细胞介素-10(IL-10)、肿瘤坏死因子α（TNF-α）和IL-1β蛋白表达,ELISA法检测培养细胞上清液中IL-10、TNF-α和IL-1β蛋白含量。 结果 CCK-8 法检测结果显示,OGD/R损伤后对照组、1、5、20、40和80 μmol/L白藜芦醇组细胞活力均较正常组降低（P＜0.05,n=3）,但5、20和 40 μmol/L白藜芦醇组细胞活力较对照组显著增强（P＜0.05,n=3）,以20 μmol/L组最强。流式细胞术、免疫荧光、Western blotting和ELISA法显示,对照组和白藜芦醇组CD11b、Iba1、Caspase-3、Bax、IL-10、TNF-α、IL-1β蛋白表达或含量或凋亡细胞百分比均显著高于正常组（P＜0.05,n=3）,但白藜芦醇组除IL-10蛋白表达或含量较对照组增高外,其余均 低于对照组（P＜0.05,n=3）。结论 白藜芦醇预处理可抑制OGD/R后小胶质细胞的活化及凋亡,减轻炎症反应。     

硫化氢通过调控NF-κB通路抑制阿霉素引起的心肌细胞炎症与细胞毒性

 目的：探讨硫化氢（H2S）是否通过调控核因子κB(NF-κB)通路抑制阿霉素（DOX）引起的心肌细胞炎症反应与细胞毒性。方法：应用Western blotting法测定NF-κB p65表达;酶联免疫吸附试验（ELISA）测定白细胞介素（IL）-1β、IL-6及肿瘤坏死因子α(TNF-α)的分泌水平;细胞计数盒（CCK-8）检测细胞存活率,Hoechst 33258核染色法检测凋亡细胞的形态学及数量的变化。结果：应用5 μmol/L DOX处理H9c2心肌细胞明显上调磷酸化NF-κB p65（p-p65）表达水平,并引起炎症反应和细胞毒性,表现为IL-1β、IL-6、TNF-α的分泌水平升高、凋亡细胞数量增多及细胞存活率降低。400 μmol/L NaHS（H2S供体）预处理30 min能显著抑制DOX对心肌细胞p-p65表达的上调作用,并减轻DOX引起的炎症反应和细胞损伤,使IL-1β、IL-6、TNF-α的分泌水平下降、凋亡细胞数量降低及细胞存活率升高。与NaHS的作用相似,NF-κB抑制剂吡咯烷二硫代氨基甲酸盐（PDTC,100 μmol/L）预处理也能阻断DOX引起的心肌炎症反应和细胞毒性。IL-1受体拮抗剂（IL-1Ra, 20 μg/L）与DOX共处理能拮抗DOX对心肌细胞NF-κB p65的激活作用及细胞毒性作用。结论：在DOX引起的心肌细胞炎症中,NF-κB通路与IL-1β之间存在正的相互作用;H2S可通过抑制NF-κB通路保护心肌细胞对抗DOX引起的炎症反应与细胞毒性。     

罗格列酮对RAW 264.7细胞源性泡沫细胞炎症反应及SOCS1和SOCS3表达的影响

 目的:观察过氧化物酶体增殖物激活受体γ（PPARγ）配体罗格列酮是否能够调节泡沫细胞促炎/抗炎反应以及细胞因子信号抑制物1（SOCS1）和细胞因子信号抑制物3（SOCS3）的表达。方法:采用ELISA法测定泡沫细胞培养液中肿瘤坏死因子α (TNF-α)、白细胞介素(IL)-6和IL-10的水平,并计算TNF-α/IL-10和IL-6/IL-10的比值。采用RT-PCR及Western blotting技术分别观察RAW 264.7细胞源性泡沫细胞SOCS1和SOCS3 mRNA及蛋白的表达。结果:RAW 264.7细胞源性泡沫细胞组细胞培养液中TNF-α、IL-6和IL-10的水平以及TNF-α/IL-10和IL-6/IL-10的比值均明显高于对照组（control）组。而罗格列酮加入泡沫细胞培养液24 h后,TNF-α、IL-6和IL-10的浓度以及TNF-α/IL-10和IL-6/IL-10的比值均明显低于泡沫细胞组。Control组和泡沫细胞组只有少量SOCS1和SOCS3 mRNA及蛋白的表达,罗格列酮作用于泡沫细胞后SOCS1和SOCS3 mRNA及蛋白的表达均明显高于control组和氧化低密度脂蛋白(ox-LDL)组。结论: 罗格列酮上调泡沫细胞SOCS1和SOCS3的表达,抑制泡沫细胞分泌TNF-α、IL-6和IL-10,调节了泡沫细胞促炎/抗炎反应。     

PYNOD对LPS活化的BV2小胶质细胞炎症因子释放的影响

 目的:观察PYNOD对LPS活化的BV2小胶质细胞炎症因子释放的影响。方法: 将表达PYNOD的重组质粒pEGFP-C2-PYNOD瞬时转染BV2细胞后,加入LPS作用24 h,Griess 法检测一氧化氮（nitric oxide, NO）的释放,实时荧光定量PCR（real-time PCR）检测诱导型一氧化氮合酶（inducible NO synthase, iNOS）和白细胞介素-1β（interleukin-1β,IL-1β）mRNA的表达,此外Western blotting和ELISA法检测iNOS和IL-1β的蛋白表达。结果: 转染PYNOD重组质粒能显著抑制LPS诱导的BV2小胶质细胞炎症因子NO的释放（P＜0.05）。Real-time PCR证实PYNOD可抑制iNOS和 IL-1β 的mRNA表达,差异有统计学意义（P＜0.05）。ELISA和Western blotting证实PYNOD可下调iNOS和 IL-1β 蛋白的表达（P＜0.05）。结论: PYNOD蛋白可以在转录水平和翻译水平显著抑制LPS刺激的BV2小胶质细胞活化产生的炎症反应。     

Iron accumulation in microglia triggers a cascade of events that leads to altered metabolism and compromised function in APP/PS1 mice

Among the changes that typify Alzheimer’s disease (AD) are neuroinflammation and microglial activation, amyloid deposition perhaps resulting from compromised microglial function and iron accumulation. Data from Genome Wide Association Studies (GWAS) identified a number of gene variants that endow a significant risk of developing AD and several of these encode proteins expressed in microglia and proteins that are implicated in the immune response. This suggests that neuroinflammation and the accompanying microglial activation are likely to contribute to the pathogenesis of the disease. The trigger(s) leading to these changes remain to be identified. In this study, we set out to examine the link between the inflammatory, metabolic and iron‐retentive signature of microglia in vitro and in transgenic mice that overexpress the amyloid precursor protein (APP) and presenilin 1 (PS1; APP/PS1 mice), a commonly used animal model of AD. Stimulation of cultured microglia with interferon (IFN)γ and amyloid‐β (Aβ) induced an inflammatory phenotype and switched the metabolic profile and iron handling of microglia so that the cells became glycolytic and iron retentive, and the phagocytic and chemotactic function of the cells was reduced. Analysis of APP/PS1 mice by magnetic resonance imaging (MRI) revealed genotype‐related hypointense areas in the hippocampus consistent with iron deposition, and immunohistochemical analysis indicated that the iron accumulated in microglia, particularly in microglia that decorated Aβ deposits. Isolated microglia prepared from APP/PS1 mice were characterized by a switch to a glycolytic and iron‐retentive phenotype and phagocytosis of Aβ was reduced in these cells. This evidence suggests that the switch to glycolysis in microglia may kick‐start a cascade of events that ultimately leads to microglial dysfunction and Aβ accumulation.     

TREM2-induced activation of microglia contributes to synaptic integrity in cognitively intact aged individuals with Alzheimer's neuropathology

The existence of individuals who remain cognitively intact despite presenting histopathological signs of Alzheimer's disease (AD), here referred to as “Nondemented with AD neuropathology” (NDAN), suggests that some mechanisms are triggered to resist cognitive impairment. Exposed phosphatidylserine (ePS) represents a neuronal “eat-me” signal involved in microglial-mediated phagocytosis of damaged synapses. A possible mediator of this process is TREM2, a microglial surface receptor activated by ligands including PS. Based on TREM2 role in the scavenging function of microglia, we hypothesize that an efficient microglial phagocytosis of damaged synapses underlies synaptic resilience in NDAN, thus protecting from memory deficits. Using immunofluorescence microscopy, we performed a comparative study of human post-mortem frontal cortices of aged-matched, AD and NDAN individuals. We studied the distribution of activated microglia (IBA1, IBA1⁺/CD68⁺ cells) and phagocytic microglia-related proteins (TREM2, DAP12), demonstrating higher microglial activation and TREM2 expression in NDAN versus AD. A study of the preservation of synapses around plaques, assessed using MAP2 and βIII tubulin as dendritic and axonal markers, respectively, and PSD95 as a postsynaptic marker, revealed preserved axonal/dendritic structure around plaques in NDAN versus AD. Moreover, high levels of PSD95 around NDAN plaques and the colocalization of PSD95 with CD68 indicated a prompt removal of damaged synapses by phagocytic microglia. Furthermore, Annexin V assay on aged-matched, AD and NDAN individuals synaptosomes revealed increased levels of ePS in NDAN, confirming damaged synapses engulfment. Our results suggest a higher efficiency of TREM2-induced phagocytic microglia in removing damaged synapses, underlying synaptic resilience in NDAN individuals.     

Lesion-associated expression of transforming growth factor-beta-2 in the rat nervous system: evidence for down-regulating the phagocytic activity of microglia and macrophages

The mechanisms that control the phagocytic activities of microglia and macrophages during disorders of the nervous system are largely unknown. In the present investigation, we assessed the functional role of transforming growth factor (TGF)beta2 in vitro and studied TGFbeta-2mRNA and protein expression in two CNS lesion paradigms in vivo characterized by fundamental differences in microglia/macrophage behaviour: optic nerve crush exhibiting slow, and focal cerebral ischemia exhibiting rapid phagocytic transformation. Furthermore, we used sciatic nerve crush injury as a PNS lesion paradigm comparable to brain ischemia in its rapid phagocyte response. In normal and degenerating optic nerves, astrocytes strongly and continuously expressed TGF-beta2 immunoreactivity. In contrast, TGF-beta2 was downregulated in Schwann cells of degenerating sciatic nerves, and was not expressed by reactive astrocytes in the vicinity of focal ischemic brain lesions during the acute phagocytic phase. In line with its differential lesion-associated expression pattern, exogenous TGF-beta2 suppressed spontaneous myelin phagocytosis by microglia/macrophages in a mouse ex vivo assay of CNS and PNS Wallerian degeneration. In conclusion, we have identified TGF-beta2 as a nervous system intrinsic cytokine that could account for the differential regulation of phagocytic activities of microglia and macrophages during injury.     

Hematopoietic MyD88-adaptor Protein Acts as a Natural Defense Mechanism for Cognitive Deficits in Alzheimer’s Disease

Accumulating evidence supports a critical role of Toll-like receptors in the clearance of Amyloid beta (Aβ) by microglial cells. Myeloid differentiation factor 88 (MyD88) is an adaptor protein that bridges the intracellular signal to nucleus for most of these innate immune receptors. We investigated here the role of competent MyD88 hematopoietic stem cells on the cognitive decline of a mouse model of Alzheimer's disease (AD). We generated classical chimeric mouse models using irradiation and transplantation of wild type GFP cells and MyD88-deficient cells. Transplantation of GFP cells essentially rescued the cognitive impairment, whereas MyD88-deficient cells significantly accelerated memory deficits of APP(swe)/PS1 mice. Moreover, we found that monocytes and microglia deficient for MyD88 exhibit a functionally impaired phagocytic reaction to Aβ.     

Phosphatidylserine expression on apoptotic lymphocytes of Xenopus laevis, the South African clawed toad, as a signal for macrophage recognition

Inflammation is avoided in apoptosis by early removal of dying cells by macrophages (MOs). In mammalian cells, an early aspect of apoptosis is the translocation of phosphatidylserine (PS) from the inner leaflet of the cell membrane to the surface. PS recognition can serve as a signal for triggering removal of dying cells. PS expression on splenocytes and thymocytes of Xenopus laevis was quantified using FITC-Annexin and flow cytometry following exposure in vitro to several known apoptogens for this species. All apoptogens used induced PS expression. Dose dependency and the kinetics of PS expression following exposure to the calcium ionophore, A23187, were also examined. Peritoneal exudate cells (PEC's) were cultured with A23187-treated thymocytes to test MO capacity for recognition of PS. MO binding to apoptotic thymocytes was reduced following exposure of PEC's to a water soluble analogue of PS, phospho-L-serine. The presence of a phagocytic PS-dependent recognition system in amphibia is supportive of the evolutionary conservation of this function in mammals that is crucial in limiting inflammation induced by dying cells.     

CC chemokine receptor 8 in the central nervous system is associated with phagocytic macrophages

CC chemokine receptor 8 (CCR8) has been detected in vitro on type 2 helper and regulatory lymphocytes, which might exert beneficial functions in multiple sclerosis (MS) and on macrophages and microglia, possibly promoting tissue injury in MS lesions. To discriminate the relevant expression pattern in vivo, we defined the cell types that expressed CCR8 in MS lesions and determined the relationship of CCR8 expression and demyelinating activity. CCR8 was not expressed on T cells but was associated with phagocytic macrophages and activated microglia in MS lesions and directly correlated with demyelinating activity. To identify factors associated with CCR8 expression, the study was extended to other central nervous system (CNS) pathologies. CCR8 was consistently expressed on phagocytic macrophages and activated microglia in stroke and progressive multifocal leukoencephalopathy, but not expressed on microglia in pathologies that lacked phagocytic macrophages such as senile change of the Alzheimer's type. CCR8 was up-regulated by macrophage differentiation and activating stimuli in vitro. In summary CNS CCR8 expression was associated with phagocytic macrophages and activated microglial cells in human CNS diseases, suggesting that CCR8 may be a feasible target for therapeutic intervention in MS. CCR8 expression may also indicate a selective program of mononuclear phagocyte gene expression.     

Effect of red blood cells and red blood cell ghosts on reticuloendothelial system function

Previous studies have shown that hepatic phagocytosis of red blood cell (RBC) stroma can depress reticuloendothelial system (RES) phagocytic function and increase susceptibility to shock. Since the RBC stroma used in these experiments contained substantial amounts of adherent hemoglobin, the present study was carried out to evaluate the role of the hepatic uptake of RBC membrane material on RES phagocytic function and susceptibility to endotoxin shock in rats. Neuraminidase-treated RBC which contained normal amounts of hemoglobin and RBC ghosts which were hemoglobin-free were used. Both preparations were removed from the circulation primarily by the liver. RES phagocytic function was depressed following the hepatic uptake of 29 X 10(8) neuraminidase-treated RBC and 26 X 10(8) RBC ghosts. RES uptake of neuraminidase-treated RBC was associated with an increase in susceptibility to endotoxin shock, but RBC ghosts did not affect shock susceptibility. Thus, RBC ghosts and intact RBC are equally effective in depressing RES phagocytic function, but RBC ghosts did not affect susceptibility to endotoxin shock.     

褪黑素对AD模型小鼠脑内小胶质细胞的影响

目的探讨褪黑素对APP/PS1转基因AD模型小鼠脑内小胶质细胞和炎症细胞因子COX-2的抑制效应。方法 AD转基因小鼠随机分为褪黑素处理组和对照组。14 d后,取海马通过免疫荧光化学染色检测小胶质细胞、老年斑位置情况;Western blot、ELISA方法分别检测CD11b、COX-2的变化;Western blot检测炎症信号通路TLR/NF-κB的变化。结果免疫荧光化学显示,老年斑周围有大量活化的小胶质细胞聚集;Western blot、ELISA结果显示褪黑素组小鼠脑内CD11b、COX-2表达显著减少;褪黑素组小鼠TLR/NF-κB炎症信号通路的TLR2、NF-κB-p65表达减少。结论褪黑素可能通过抑制TLR/NF-κB炎症信号通路来抑制小胶质细胞活化并抑制炎症细胞因子COX-2的分泌。     

FSD-C10调节阿尔茨海默病双转基因小鼠炎性微环境

目的:探讨新型Rho激酶抑制剂FSD-C10对阿尔茨海默病(Alzheimer disease,AD)模型小鼠脑内炎性微环境的调节作用。方法:采用双转染人β-淀粉样蛋白前体(β-amyloid protein precursor,APP)695swe基因和人早老素1(presenilin-1,PS1)ΔE9突变基因的8月龄小鼠作为AD动物模型,随机分为模型组和FSD-C10治疗组,分别经腹腔注射生理盐水和FSD-C10(25 mg·kg~(-1)·d~(-1))持续治疗2个月,同月龄野生型小鼠作为正常对照组。应用Morris水迷宫(Morris water maze,MWM)实验检测小鼠学习和记忆能力。采用免疫组化和Western blot技术检测小鼠脑组织β-淀粉样蛋白(Aβ)、磷酸化Tau蛋白(p-Tau)、β位点APP剪切酶(BACE)、Toll样受体4(TLR-4)、磷酸化核因子κB(p-NF-κB)、诱导型一氧化氮合酶(i NOS)和精氨酸酶1(Arg-1)的表达。结果:与模型组相比,FSD-C10干预能显著改善APP/PS1双转基因小鼠学习和记忆能力,减少海马区Aβ1-42、p-Tau和BACE的表达,抑制脑内炎症信号通路TLRs/NF-κB轴TLR-4的表达和p-NF-κB的激活,减少i NOS的表达,增加Arg-1的表达。结论:FSD-C10干预能明显改善APP/PS1双转基因小鼠的学习和记忆能力,其机制可能是通过抑制TLRs/NF-κB信号通路激活,减少炎症因子的分泌及促进M1型炎性小胶质细胞向M2型抗炎小胶质细胞转化,从而改善APP/PS1双转基因小鼠脑组织炎症微环境。     

天麻素对缺血缺氧脑损伤新生大鼠小胶质细胞Sirt3表达的影响

目的:研究天麻素对缺血缺氧脑损伤(HIBD)新生大鼠脑内激活的小胶质细胞Sirt3表达的影响。方法:选取39只3 d龄SD幼年大鼠随机分为对照组(control)、缺血缺氧脑损伤组(HIBD)、天麻素组(HIBD+gastrodin)。采用左侧颈总动脉结扎结合缺氧法建立新生大鼠缺血缺氧性脑损伤(HIBD)模型,使用免疫荧光染色观察HIBD模型后新生大鼠大脑胼胝体区小胶质细胞的分布情况;使用免疫荧光双标染色及Western Blot检测大鼠大脑左侧胼胝体区小胶质细胞Sirt3的表达变化。结果:免疫荧光染色结果显示HIBD后新生大鼠大脑左侧胼胝体区小胶质细胞出现明显激活,确定模型建立成功。免疫荧光双标染色及Western Blot结果均显示,与对照组相比,HIBD模型组Sirt3的表达水平明显升高(P<0.05);与HIBD模型组相比,天麻素组Sirt3的表达进一步增强(P<0.05)。结论:天麻素可能通过促进新生大鼠脑内小胶质细胞Sirt3的表达,发挥其神经保护作用。