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1.
原核生物、真核生物、植物体的非神经细胞和组织中,尤其是多种免疫活性细胞中,均证实乙酰胆碱酯酶(acetylcholinesterase,AChE)、胆碱乙酰转移酶(choline acetyltransferase,ChAT)和乙酰胆碱受体(acetylcholine receptor, AChR)各亚型在内的胆碱能系统组分的存在,其中烟碱样乙酰胆碱受体α7(nicotinic acetylcholine receptor α7,nAChRα7)是烟碱样胆碱能抗炎通路(nicotinic anti-inflammatory pathway)中重要的分子核心机制,同时也是机体限制宿主防御反应扩大的内源性抗炎机制之一. 本文旨在探讨(前)脂肪细胞上非神经元型胆碱能系统是否存在及初步揭示烟碱样胆碱能受体α7对前脂肪细胞功能的影响. 以体外培养的3T3-L1前脂肪细胞为研究对象,采用免疫组化和蛋白质免疫印迹技术,分别检测前脂肪细胞和成熟脂肪细胞中乙酰胆碱酯酶、胆碱乙酰转移酶和烟碱样乙酰胆碱受体α7的3种胆碱能系统主要组分的蛋白表达. 另将前脂肪细胞分为给予广谱烟碱样乙酰胆碱受体激动剂尼古丁、特异性烟碱样乙酰胆碱受体α7激动剂氯化胆碱及特异性烟碱样乙酰胆碱受体α7拮抗剂甲基牛扁亭碱干预12 h、24 h、36 h,并设立相应处理时间的空白对照组,逆转录聚合酶链反应检测前脂肪细胞visfatin mRNA表达情况. 免疫组化染色可见前脂肪细胞中AChE、ChAT及AChRα7均有阳性表达;蛋白免疫印迹检测进一步半定量证实了前脂肪细胞和成熟脂肪细胞中AChE、ChAT及AChRα7的蛋白表达;拮抗剂甲基牛扁亭碱(106~104mol/L)时间、剂量依赖性上调前脂肪细胞visfatin mRNA表达(1.3~1.55fold,P<0.01),与对应空白对照组相比,存在显著性统计学差异; 加入不同剂量的尼古丁和氯化胆碱,则前脂肪细胞中visfatin mRNA表达水平与对应空白对照组相比,均不同程度地下降,其中以氯化胆碱的抑制效应更为显著. 前脂肪细胞与成熟脂肪细胞中均存在有独立的胆碱能体系,其中AChRα7很可能在调节脂肪细胞因子分泌及肥胖相关的病理生理过程中发挥重要作用.  相似文献   

2.
用膜片箝方法,在标定的爪蟾胚胎脊髓胆碱能神经细胞膜上记录钙离子单通道电流。结果显示,在静息膜电位时钙通道即有开放活动。根据通道的电导及动力学等特性,我们将其分为两种类型:NS 型钙通道,斜率电导7.5pS,静息膜电位时平均开放时间0.58ms,其活动受牵张膜片的影响;NL 型钙通道,斜率电导16.7pS,静息膜电位时二级平均开放时间分别是2ms 和19.3ms。鉴于它们在膜静息以及负电位相的显著活动,我们推测这两类钙通道可能参与神经元静息膜电位时钙依赖的细胞活动过程。  相似文献   

3.
前脑基底-大细胞基底核-新皮是胆碱类物质作用的中枢。乙酰胆碱在此区域接受刺激并提供信息到大脑皮层和杏仁核,介导认知过程的产生。采用基因转移技术将果蝇胆碱乙锘转移酶基因植入基因工程细胞载体-纤维母细胞,后者经脑内移植作用于大细胞基底核神经元,释放乙酰胆或胆碱。  相似文献   

4.
胆碱能抗炎通路在炎症反应中的作用   总被引:2,自引:0,他引:2  
胆碱能抗炎通路是调节免疫系统的一种神经生理机制,其在脾脏、肝脏和胃肠道等网状内皮系统通过释放乙酰胆碱抑制细胞因子的合成,控制炎症反应。乙酰胆碱与巨噬细胞和其他分泌细胞因子细胞表面的α7烟碱型乙酰胆碱受体相互作用,抑制致炎细胞因子的合成与释放,防止组织损伤。本文着重综述胆碱能抗炎通路调节炎症反应的神经生理机制及其在炎症性疾病中的干预价值。  相似文献   

5.
目的探讨小胶质细胞活化规律与脂多糖(Lipopolysaccharide,LPS)诱导黑质多巴胺(DA)能神经元变性的关系。方法脑立体定位注射LPS入大鼠脑黑质后,采用特异性抗体0x.42标记不同时间点小胶质细胞的激活情况;酪氨酸羟化酶(tyrosine-hydroxylase,TH)免疫组织化学观察DA能神经元损害变化。结果小胶质细胞在LPS注入黑质6h后开始出现部分激活。12h大部分激活,为“灌木丛样”小胶质细胞;24h已完全激活,呈现“阿米巴样”,在随后的30d内,基本维持在此形态。而TH阳性细胞数在第3d开始出现下降,与对照组相比下降达45%,14d时下降至5~10%,至30d时几乎完全消失。结论小胶质细胞的激活先于DA能神经元变性,其激活介导的炎症反应在PD发病中具有重要的神经破坏作用。  相似文献   

6.
目的:通过观察晚期非小细胞肺癌患者TKI治疗前后外周血IgG、IgM、IgA、C3、C4、C-反应蛋白及CD3+、CD4+、CD8+、CD4+/CD8+细胞的表达变化,探讨TKI治疗对晚期非小细胞肺癌患者免疫功能的影响及意义。方法:检测TKI组30例非小细胞肺癌患者TKI治疗前、治疗一个月后外周血IgG、IgM、IgA、C3、C4、C-反应蛋白及CD3+、CD4+、CD8+、CD4+/CD8+细胞表达水平,分析表达变化及与疗效的关系。30例非小细胞肺癌患者作为对照组。结果:治疗前,TKI组与对照组IgG、IgM、IgA、C3、C4、C-反应蛋白水平基本正常,但CD4+细胞数量减低、CD4+/CD8+比值较低、CD8+细胞数量增高,两组相比IgG、IgM、IgA、C3、C4、C-反应蛋白、CD3+、CD4+、CD8+、CD4+/CD8+差异均无统计学意义(P0.05);TKI治疗一个月后,TKI组与对照组IgG、IgM、IgA、C3、C4、C-反应蛋白水平无明显变化,而CD4+细胞数量增多、CD4+/CD8+较前增高,CD8+细胞数量较前减低,两组相比CD3+、IgG、IgM、IgA、C3、C4、C-反应蛋白差异无统计学意义(P0.05),而CD4+、CD4+/CD8+、CD8+差异有统计学意义(P0.01)。结论:TKI治疗后,晚期非小细胞肺癌患者细胞免疫功能得到改善,体现在CD4+、CD8+细胞数量的变化上,且TKI治疗的疗效可通过比较外周血CD4+、CD4+/CD8+、CD8+细胞表达变化体现。  相似文献   

7.
流行性乙型脑炎(epidemic encephalitis type B,简称乙脑)是由乙型脑炎病毒(encephalitis B virus,简称乙脑病毒)感染引起的中枢神经系统疾病。乙脑病毒感染具有明显的嗜神经性,它在神经元细胞中大量增殖并造成其损伤,以干扰素(interferons, IFNs)为核心的固有免疫应答在机体抵御乙脑病毒感染的过程中发挥重要作用。多项研究表明,乙脑病毒感染神经元细胞后,宿主细胞模式识别受体可识别病毒的结构成分,并经接头分子和转录因子等信号传递,介导IFN的产生。IFN随后激活下游干扰素信号通路,转录多种干扰素诱导基因(interferon stimulated genes, ISGs),启动宿主对病毒的固有免疫应答反应。现就乙脑病毒感染神经元细胞的固有免疫相关分子,如模式识别分子、关键接头分子、转录因子及IFN信号转导过程中相关的调控分子作一概述。  相似文献   

8.
目的研究中国穿山甲消化道5-羟色胺(5-HT)免疫活性细胞的分布和形态。方法应用链霉菌抗生物素蛋白一过氧化物酶免疫组织化学方法(S-P法)。结果中国穿山甲消化道5-HT细胞在胃幽门部密度最高,食道、胃贲门部和胃体中未见分布。肠道5-HT细胞密度从十二指肠、空肠到回肠依次减少,至大肠又显著升高(P〈0.01)。5-HT细胞形态多样,主要有圆形、椭圆形和锥形,肠上皮中锥形5-HT细胞通过顶部较长的胞突通向肠腔,基部较宽的胞体与固有层相接触。结论中国穿山甲消化道5-HT细胞的分布和形态同其它动物有相似之处,也有其自身特点。中国穿山甲消化道中5-HT细胞的分布与其食性是相适应的。  相似文献   

9.
采用ABC免疫组织化学法,应用5—羟色胺(5-HT)特异性抗血清,对枕纹锦蛇(Elaphe dione)消化道内含有的5—HT内分泌细胞进行了免疫组织化学的定位研究和形态学观察。结果显示,5-HT细胞在消化道各部位的分布密度呈倒“V”形,以十二指肠最高,胃贲门部最低。其形态多样,上段(食管、胃)多为圆形和椭圆形,主要分布于上皮基部和腺泡上皮之间;中段(十二指肠、空肠、回肠)以细长锥体形、梭形、圆形为主,主要分布于上皮基部和上皮细胞之间;下段(直肠)为圆形,分布于上皮基部。锥体形细胞常有一个长突起伸入到固有膜或肠腔,行使内或外分泌功能;梭形细胞有两个细长突起,一个指向固有膜,另一个指向肠腔,表明这种细胞可能具有内、外分泌的双重功能。  相似文献   

10.
目的:探讨乌苯美司联合紫杉醇与顺铂(TP)方案治疗晚期非小细胞肺癌的临床疗效及对患者免疫功能的影响。方法:选择2013年10月-2015年6月在我院接受治疗的晚期非小细胞肺癌患者60例,随机分为研究组和对照组。两组患者均给予全身化疗治疗,研究组在此基础上给予口服乌苯美司治疗。观察并比较两组患者的临床疗效、免疫功能变化及不良反应的发生情况。结果:研究组患者治疗有效率明显高于对照组,差异具有统计学意义(P0.05);两组肿瘤控制情况比较,差异无统计学意义(P0.05);与治疗前比较,两组患者治疗后外周血CD3~+,CD4~+,CD4~+/CD8~+及NK细胞升高,而CD8~+下降,差异具有统计学意义(P0.05);与对照组比较,研究组患者治疗后外周血CD3~+,CD4~+,CD4~+/CD8~+及NK细胞显著升高,而CD8~+显著降低,差异具有统计学意义(P0.05);研究组患者白细胞减少、恶心、呕吐及骨髓抑制等不良反应的发生率低于对照组,差异具有统计学意义(P0.05)。结论:乌苯美司联合TP方案能够改善晚期非小细胞肺癌患者机体免疫功能,减少不良反应的发生率,值得临床推广应用。  相似文献   

11.

Background

Acetylcholine (ACh) is known to be a key neurotransmitter in the central and peripheral nervous systems, which is also produced in a variety of non-neuronal tissues and cell. The existence of ACh in maxilla in vivo and potential regulation role for osteogenesis need further study.

Results

Components of the cholinergic system (ACh, esterase, choline acetyltransferase, high-affinity choline uptake, n- and mAChRs) were determined in maxilla of rat in vivo, by means of Real-Time PCR and immunohistochemistry. Results showed RNA for CarAT, carnitine/acylcarnitine translocase member 20 (Slc25a20), VAChT, OCTN2, OCT1, OCT3, organic cation transporter member 4 (Slc22a4), AChE, BChE, nAChR subunits α1, α2, α3, α5, α7, α10, β1, β2, β4, γ and mAChR subunits M1, M2, M3, M4, M5 were detected in rat’s maxilla. RNA of VAChT, AChE, nAChR subunits α2, β1, β4 and mAChR subunits M4 had abundant expression (2-ΔCt > 0.03). Immunohistochemical staining was conducted for ACh, VAChT, nAChRα7 and AChE. ACh was expressed in mesenchymal cells, chondroblast, bone and cartilage matrix and bone marrow cells, The VAChT expression was very extensively while ACh receptor α7 was strongly expressed in newly formed bone matrix of endochondral and bone marrow ossification, AchE was found only in mesenchymal stem cells, cartilage and bone marrow cells.

Conclusions

ACh might exert its effect on the endochondral and bone marrow ossification, and bone matrix mineralization in maxilla.

Electronic supplementary material

The online version of this article (doi:10.1186/0717-6287-47-72) contains supplementary material, which is available to authorized users.  相似文献   

12.
Increasing evidence has shown the expression of the non-neuronal cholinergic system in endothelial cells. In the present experiments the expression of choline acetyltransferase (ChAT) was investigated in human endothelial cells by anti-ChAT immunohistochemistry and anti-ChAT immunofluorescence. Positive ChAT immunoreactivity was found in cultures of human umbilical endothelial cells (HUVEC) and a human angiosarcoma cell line (HAEND). In HUVEC and HAEND choline acetyltransferase activity and small amounts of acetylcholine were also detected. Positive ChAT-immunoreactivity was demonstrated in situ in endothelial cells of the human umbilical cord. In addition, in experiments with confocal laser scanning microscopy positive anti-ChAT immunoreactivity was found in situ in endothelial cells of human skin blood vessels. In the first functional experiments with HUVEC acetylcholine appeared to mediate a small facilitatory effect on the expression of intracellular adhesion molecule-1. The present experiments demonstrate the wide existence of ChAT in human endothelial cells. Further experiments are addressed to elucidate the biological role of acetylcholine in the endothelium and possible differences between the different subtypes of endothelial cells.  相似文献   

13.
14.
Acetylcholine, a prime example of a neurotransmitter, has been detected in bacteria, algae, protozoa, and primitive plants, indicating an extremely early appearance in the evolutionary process (about 3 billion years). In humans, acetylcholine and/or the synthesizing enzyme, choline acetyltransferase (ChAT), have been found in epithelial cells (airways, alimentary tract, urogenital tract, epidermis), mesothelial (pleura, pericardium), endothelial, muscle and immune cells (mononuclear cells, granulocytes, alveolar macrophages, mast cells). The widespread expression of non-neuronal acetylcholine is accompanied by the ubiquitous presence of cholinesterase and receptors (nicotinic, muscarinic). Thus, the non-neuronal cholinergic system and non-neuronal acetylcholine, acting as a local cellular signaling molecule, has to be discriminated from the neuronal cholinergic system and neuronal acetylcholine, acting as neurotransmitter. In the human placenta anti-ChAT immunoreactivity is found in multiple subcellular compartments like the cell membrane (microvilli, coated pits), endosomes, cytoskeleton, mitochondria and in the cell nucleus. These locations correspond with the results of experiments where possible functions of non-neuronal acetylcholine have been identified (proliferation, differentiation, organization of the cytoskeleton and the cell-cell contact, locomotion, migration, ciliary activity, immune functions). In the human placenta acetylcholine release is mediated by organic cation transporters. Thus, structural and functional differences are evident between the non-neuronal and neuronal cholinergic system. Enhanced levels of acetylcholine are detected in inflammatory diseases. In conclusion, it is time to revise the role of acetylcholine in humans. Its biological and pathobiological roles have to be elucidated in more detail and possibly, new therapeutical targets may become available.  相似文献   

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17.
Inflammatory responses, characterized by the overproduction of numerous proinflammatory mediators by immune cells, is essential to protect the host against invading pathogens. Excessive production of proinflammatory cytokines is a key pathogenic factor accounting for severe tissue injury and disease progression during the infection of multiple viruses, which are therefore termed as “cytokine storm”. High mobility group box 1 (HMGB1), a ubiquitous DNA-binding protein released either over virus-infected cells or activated immune cells, may act as a proinflammatory cytokine with a robust capacity to potentiate inflammatory response and disease severity. Moreover, HMGB1 is a host factor that potentially participates in the regulation of viral replication cycles with complicated mechanisms. Currently, HMGB1 is regarded as a promising therapeutic target against virus infection. Here, we provide an overview of the updated studies on how HMGB1 is differentially manipulated by distinct viruses to regulate viral diseases.  相似文献   

18.
The non-neuronal cholinergic system is widely expressed in human airways, skin and immune cells. Choline acetyltransferase (ChAT), acetylcholine and nicotine/muscarine receptors are demonstrated in epithelial surface cells, submucosal glands, airway smooth muscle fibres and immune cells. Moreover, acetylcholine is involved in the regulation of cell functions like proliferation, differentiation, migration, organization of the cytoskeleton, cell-cell contact, secretion and transport of ions and water. Cystic fibrosis (CF), the most frequent genetic disorder, is known to be caused by a mutation of the CF-gene coding for the cystic fibrosis transmembrane regulator protein (CFTR). CFTR represents a regulating transport protein for ion channels and processes involving endo- and exocytosis. Despite the identification of the genetic mutation knowledge of the underlying cellular pathways is limited. In the present experiments the cholinergic system was investigated in the peripheral blood and in the lung of CF patients undergoing lung transplantation (n=7). Acetylcholine content in bronchi and lung parenchyma of CF was reduced by 70% compared to controls (tumor-free tissue obtained from patients with lung tumor; n=13). In contrast, ChAT activity was elevated to some extent (p>0.05) in CF, and esterase activity did not differ from control. Acetylcholine content extracted from peripheral leucocytes (30 ml) was also reduced by 70% in CF (n=13) compared to healthy volunteers (n=9). Double labelling experiments with anti-CF antibodies and anti-ChAT antibodies showed a co-localization in peripheral lymphocytes, giving first evidence that CFTR may be linked with the intracellular storage/transport of non-neuronal acetylcholine. It is concluded that the non-neuronal cholinergic system is involved in the pathogenesis of CF. A reduced content of non-neuronal acetylcholine could contribute to the deleterious changes of epithelial ion and water movements in CF, because acetylcholine stimulates apical Cl(-) secretion, inhibits apical Na(+) and water absorption and therewith facilitates mucociliary clearance.  相似文献   

19.
Mechanisms that regulate neural stem cell activity in the adult brain are tightly coordinated. They provide new neurons and glia in regions associated with high cellular and functional plasticity, after injury, or during neurodegeneration. Because of the proliferative and plastic potential of neural stem cells, they are currently thought to escape their physiological control mechanisms and transform to cancer stem cells. Signals provided by proteins of the transforming growth factor (TGF)-beta family might represent a system by which neural stem cells are controlled under physiological conditions but released from this control after transformation to cancer stem cells. TGF-beta is a multifunctional cytokine involved in various physiological and patho-physiological processes of the brain. It is induced in the adult brain after injury or hypoxia and during neurodegeneration when it modulates and dampens inflammatory responses. After injury, although TGF-beta is neuroprotective, it may limit the self-repair of the brain by inhibiting neural stem cell proliferation. Similar to its effect on neural stem cells, TGF-beta reveals anti-proliferative control on most cell types; however, paradoxically, many brain tumors escape from TGF-beta control. Moreover, brain tumors develop mechanisms that change the anti-proliferative influence of TGF-beta into oncogenic cues, mainly by orchestrating a multitude of TGF-beta-mediated effects upon matrix, migration and invasion, angiogenesis, and, most importantly, immune escape mechanisms. Thus, TGF-beta is involved in tumor progression. This review focuses on TGF-beta and its role in the regulation and control of neural and of brain-cancer stem cells. This work was supported by the German Federal Ministry of Education and Research (BMBF no. 01GA0510 and no. 0312134) and by the Bavarian State Ministry of Sciences, Research and the Arts, "Forneurocell grant".  相似文献   

20.
Summary The neurophysin that is biosynthesised in association with the neurohypophysial hormone vasopressin (vasopressin-neurophysin) affects the growth and DNA synthesis of rat hypothalamic non-neuronal cells in culture. Over a narrow range of concentrations vasopressin-neurophysin stimulated growth, as assessed by increase in cell numbers, about five-fold, in conditions where fetal calf serum concentration was limiting (0.2% fetal calf serum). Maximum stimulation occurred in the presence of 20 to 30 ng vasopressin-neurophysin per ml of medium. DNA synthesis was increased by a factor of three in the presence of 30 ng vasopressin-neurophysin per ml of medium. At least two populations of non-neuronal hypothalamic cells were present in the cultures, and these were both affected by vasopressin-neurophysin.This study allows the suggestion that neurophysin may be acting as a growth-regulating factor at its release site, playing a part in the interactions of neurones and glial cells in the hypothalamo-neurohypophysial system.  相似文献   

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