神经生物学相关论文摘要

1、神经生物学相关论文摘要1. 在MN9D细胞-synuclein N、NAC、C端结构域与线粒体关系的研究张韬 硕士2009帕金森病（PD）是最常见的神经退行性疾病之一，a-突触核蛋白（a-synuclein）及线粒体与PD发病密切相关，但作用机制尚不明确。a-synuclein是PD病理特征Lewy体的主要成分, a-synuclein基因突变可导致家族性PD，大多数PD患者存在线粒体功能障碍。本课题前期工作证实a-synuclein可位于线粒体，其在大鼠体内长期过表达可引起神经元线粒体结构变化，导致线粒体退行性变。本实验的目的是研究a-synuclein各结构域与线粒体结构功能的关系。我们成

2、功构建了a-synuclein 基因的各结构域：pLNCX2/N，pLNCX2/NAC及pLNCX2/C的逆转录病毒的表达质粒，通过病毒包装获得了可表达a-synuclein各结构域的MN9D细胞。利用免疫细胞化学方法，通过激光扫描共焦显微镜发现a-synuclein/N端与线粒体存在共定位关系；a-synuclein/NAC主要在核内聚集表达；a-synuclein/C端在胞浆和胞核内均有表达。JC1染色流式细胞仪检测显示，过表达a-synuclein/N实验组细胞线粒体膜电位降低，同时CCK8检测结果显示该组细胞活力较正常组及其它处理组明显下降。凋亡检测显示，过表达a-synuclein/

3、N可引起AIF总量增加及核转位，刺激细胞色素C释放，吖啶橙检测发现引起核DNA断裂以及线粒体形态发生变化。Annexin V/PI染色的直接证据表明a-synuclein/N参与凋亡并最终导致细胞死亡。电镜形态学观察发现a-synuclein/N可导致线粒体形态发生明显改变。因此我们认为a-synuclein的 N端可定位于线粒体，具有细胞毒性作用，并参与调节线粒体功能；a-synuclein/NAC虽具有疏水特性但却能穿过核膜，聚集在核仁周围，发挥着核内调控作用；a-synuclein/C端定位于胞浆和核内可能参与多种细胞功能且不排除其参与细胞保护作用。Mitochondrial dysfu

4、nction is implicated in the pathophysiology of Parkinsons disease characterized by formation of intraneuronal inclusions, Lewy bodies and progressive degeneration of the nigrostriatal dopamine system. Recently, pathophysiological functions of a-synuclein, a major constituent of Lewy bodies, have bee

5、n shown in its interaction with mitochondria. Our present study is to identify which domain of a-synuclein is to be the key in affecting mitochondrial function, and how the function is to be impaired by alteration of a-synuclein. For this purpose, an N-terminal (amino acids 1-65), NAC (61-95), and C

6、-terminal (91-140) fragments of a-synuclein were generated, and retroviral expression system was employed for transfection. Confocal microscopy, flow cytometry, Western blot analysis and electron microscope techniques were employed to evaluate co-localization of target protein and mitochondrion, mit

7、ochondrial membrane potential, mitochondrial modality, and direct interaction of interested proteins in MN9D cells. The results demonstrated that only the N-terminal fragment of a-synuclein was localized on mitochondria, causing the decline of mitochondrial membrane potential. Upon over-expressing o

8、f the N-terminus, cell viability was significantly decreased and the mitochondria were dramatically changed in shape. These results suggested that under altered conditions of a-synuclein expression, a-synuclein on mitochondria might produce enhanced toxicity leading to the eventual neuronal cell dea

9、th. Moreover, in order to examine apoptosis-related molecular events, apoptosis-inducing factor, cytochrome c release, together with Annexin V staining were employed to this cell model to analyze the cell death mechanism with alteration of a-synuclein, which revealed apoptotic events were apparently

10、 involved in the toxicity of N-terminal of a-synuclein2.  在多巴胺能神经元磷酸化的 -SYN 参与保护作用及 TH 的调节机制刘琦 硕士2009帕金森病（Parkinsons Disease, PD）是临床上最常见的老年神经退行性疾病之一。其典型的神经病理学特征为中脑黑质多巴胺 (dopamine, DA) 能神经元选择性进行性缺失，同时残存的神经元胞浆和轴突内出现路易氏体（Lewy body）和路易氏神经索。-突触核蛋白（-SYNuclein，-SYN）是一种与遗传性和散发性PD均密切相关的磷蛋白，-SYN的异常表达和突变均

11、能导致PD的发生。已有研究发现，在路易氏体（Lewy body）中，-SYN磷酸化程度可达90%，远远超出正常生理情况下4%的磷酸化水平，且修饰位点仅为C端129位的丝氨酸。但到目前为止，磷酸化-SYN在PD发病过程中的作用仍不是很清楚，为了进一步明确磷酸化-SYN对多巴胺能神经元的影响及参与TH调控的机制，进行了如下实验。 本 实 验 室 已 经 成 功 构 建 了 逆 转 录 病 毒 载 体 携 带 的 野 生 型 -SYN (WT/-SYN) ， 模 拟 磷 酸 化 -SYN （ S129D/-SYN ） 和 抑 制 磷 酸 化 -SYN（S129A/-SYN），通过病毒包装和筛选，收集

12、病毒上清，感染 MN9D 细胞，通过 real-time PCR 检测细胞内各基因的表达水平，结果显示各组细胞内，-SYN的表达较正常组明显增加。感染细胞 24 和 48h 后，光镜下观察细胞形态，结果显示过表达 WT/-SYN 组细胞形态不规则，突起减少，胞体肿胀，且增殖减慢。Confocal 观察感染 48h 后的细胞，发现过表达 S129D/-SYN 组胞核及胞浆内出现了较为明显的 -SYN 聚集，过表达 S129A/-SYN 组细胞内 -SYN 呈聚集趋势，而过表达 WT/-SYN 组细胞内未见 -SYN 聚集现象。CCK-8 检测感染后 48h细胞活力，发现各组 MN9D 细胞活力较

13、对照组相比均明显下降（*p<0.05，*p<0.01），且过表达 WT/-SYN 组细胞活力明显低于过表达 S129D/-SYN 组和S129A/-SYN 组（#p<0.01)，以上结果提示过表达野生型 -SYN 可以引起细胞内寡聚体形式的 -SYN 增加，其毒性损伤多巴胺能神经元，磷酸化 -SYN 可能通过形成不可溶的蛋白聚集体，使寡聚状态的 -SYN 聚集，抑制对细胞的毒性损伤，从而保护细胞活力。阻抑磷酸化的 -SYN 亦可引起 -SYN 呈聚集状态，可能由于聚集体形成较磷酸化晚，故保护作用不如磷酸化明显。 酪氨酸羟化酶（TH）是多巴胺合成的限速酶，磷酸化 -突触核蛋白是

14、否对TH 的表达和活性具有调节作用，可能的作用机制以及二者之间是否有直接或间接相互作用关系目前尚无明确报道。 本 实 验 将 构 建 好 的 野 生 型 及 两 种 突 变 的 myc-SYN 标 签 蛋 白 和pcDNA3.0-TH 共同转染于 HEK293T 细胞内，通过免疫共沉淀的方法，检测各组-SYN 和 TH 之间是否存在相互作用关系，结果均发现阳性条带。将构建好的野生型及两种突变的荧光标签蛋白 HaloTag-SYN 和 pcDNA3.0-TH 共转染于HEK293T 细胞，通过免疫细胞化学荧光方法，Confocal 检测，可见各组 -SYN和 TH 之间存在共定位。Western

15、-blot 结果证实过表达 S129D/-SYN 可以上调TH 的活性（*p<0.05），同时对 TH 的表达水平无影响；过表达 S129D/-SYN，PP2A 表达水平明显下降（*p<0.01），磷酸化 ERK1/2 水平增强（*p<0.01）；而过表达 WT/-SYN 结果正好相反，同时蛋白激酶 A 水平并无显著性改变。以上试验结果提示，磷酸化 -SYN 可以上调 TH 的活性。其调节机制可能不是通过与其相互作用，而是通过调节 PP2A 和 ERK 通路实现的。 综合以上实验结果，本实验室认为，在 PD 的发展过程中，寡聚状态可溶的-SYN 对多巴胺能神经元具有毒性损伤作

16、用，磷酸化 -SYN 通过促进形成不溶性的 -SYN 聚集体，局限了寡聚体 -SYN 引起的细胞毒性，并进一步促进蛋白酶体系统对其清除，从而在一定程度上抑制了野生型 -SYN 过表达引起的细胞毒性损伤。磷酸化 -SYN 水平增加，通过调节 PP2A 和 ERK 的表达和活性，提高了 TH 磷酸化水平，增强了 TH 活性，促进多巴胺的合成和分泌，弥补了野生 型 -SYN 过表达导致的 TH 活性抑制和多巴胺合成不足。Parkinsons disease is one of the most common progressive neurodegenerative disorders. The t

17、ypical neuropathologic characters are the selectively progressive deletion of dopaminergic neurons and formation of Lewys bodys in lived neuro endochylema and axon. lpha-synuclein（-SYN） is a protein associated with familial and sporadic PD. The abnormal expression and mutation of -SYN can induce PD.

18、 Most researche has found that -SYN is hyperphosphorylated at 129 serine, approximately 90% in Lewy bodys, while remains only 4% in normal. But by now, it is still unclear that the mechenism of phosphorylated -SYN in PD. In order to indentify how phosphorylated -SYN involved in dopaminergic neuron a

19、nd regulates the expression and activity of TH, we design experiments as follow. WT/-SYN, S129D/-SYN and S129A/-SYN have constructed into retrovirus vector. Virus supernatant gathered and infected in mouse dopaminergic cells MN9D, then genes expression of transfected cells was detected by real-time

20、PCR and the results show that the genes level of -SYN in all groups are obviously higher than normal. Cell morphology was observed by microscope after infected 24h and 48h. The morphology of cells WT/-SYN over-expressed was irregular, the number of project from cell body was reduced, cell bodies wer

21、e swallow and proliferation turned slowly. By confocal, protein aggregation of insoluble -SYN was found in cells S129D/-SYN over expressed, in which both were in endochylema and nucleus and -SYN acted as prone to aggregate in over expression cells of S129A/-SYN, but -SYN uniformly distributed in cel

22、ls of WT/-SYN over expressed. The cell viability was obviously reduced in all groups than contral cells after 48h infection (*p<0.05，*p<0.01). And the viability of cells infected by WT/-SYN was much lower than the other two -SYN over-expressing groups (#p<0.01). These results apply that wil

23、d type -SYN over expression could up regulate the level of oligo -SYN, which is toxic to dopaminergic neuron, and -SYN phosphorylated at 129 Ser may protect the cells through formation of insoluble -SYN aggregates. Tyrosine hydroxylase (TH) is the rate-limiting enzyme of DA synthesis, so far, there

24、are no definitly reports about whether phosphorylated -SYN can regulate the expression and the activity of TH and the possibility regulation mechanism, it is still no clear that if any directe or indirecte interaction between them. Wild type and two other mutation -SYN fusion-expressing vectors were

25、 constructed, and co-transfected to human embryo kidney cells HEK293T with pcDNA3-TH. The relation between -SYN and TH was detected by immunocytochemistry, CO-IP and GST pull-down the co-localization detected and the positive belts were found in all groups. Anterior reseache in our lab already prove

26、d that phosphorylated -SYN up-regulated the activity of TH without any change of the expression levels (*p<0.05). By Western-blot, the results showed that the level of phosphorylated ERK1/2 increased and PP2A decreased (*p<0.05, *p<0.01), while without any change of PKA. Those results indic

27、ated that the activity of TH may be up-regulated by phophosphorylated -SYN not through the direct interaction but via cell signaling pathway of ERK1/2 and PP2A. Take these into consideration, in the developing of PD, oligo -SYN causes toxic function to dopaminergic neuron. Phosphorylated -SYN promot

28、es to form insoluble -SYN aggregation and constrains the cell toxicity of oligo -SYN, then facilitates the proteasome system to constrain the toxicity by wild type -SYN. Phosphorylated -SYN elevates the activity of TH through regulating cell signaling pathway of ERK1/2 and PP2A, could increase dopam

29、ine synthesis and secretion, thus make up dopaminal quantity which has been downregulated by inhibition of TH activity through oligo -SYN formation.帕金森病相关基因PINK1和-突触核蛋白的相互作用范春香 硕士 2014帕金森病（Parkinsons Disease, PD）是临床上最常见的神经退行性疾病之一。它的主要特点是中脑黑质多巴胺能神经元的进行性缺失和胞质内路易体的形成，其中的主要成分为-synuclein，近期报导 PINK1等蛋白也在其

30、中。PD的发病机制涉及到多方面，包括：蛋白降解，氧化应激，蛋白磷酸化以及线粒体功能障碍等，具体机制仍不清楚。-synuclein和PINK1均与家族性PD有关。两者均能定位于线粒体，两者的突变体都能影响线粒体的活力。但两者之间的关系至今仍不清楚。为了研究-synuclein和PINK1之间的关系，我们首先利用多巴胺能神经元MN9D细胞，进行免疫细胞化学染色，通过共聚焦显微镜观察-synuclein和PINK1两种蛋白在细胞内的分布及共定位状态。结果显示两者主要分布于细胞浆中并且能够部分共定位，这在空间上提供了两者能够相互作用的可能性。我们进一步克隆了野生型PINK1及其突变体G309D，C14

31、5 及N35，并成功构建了含有Flag-tag的蛋白质表达载体。将本室构建的GST-synuclein经大肠杆菌BL-2l表达纯化后，与MN9D细胞裂解液共孵育，通过GST-Pull down 技术，检测到PINK1与-synuclein蛋白间的相互作用。并应用MN9D细胞的内源性PINK1与-synuclein进行免疫沉淀实验，来进一步验证两蛋白之间的相互作用。结果发现利用GST-synuclein融合蛋白捕获及免疫沉淀技术，均检测到特异的PINK1条带。采用脂质体转染的方法将本室构建的myc-synuclein及pCMV-myc，pcDNA3-Flag-PINK1及pcDNA3-Flag分

32、别单独瞬时转染293T细胞，利用myc抗体及anti-Flag M2 affinity gel进行免疫共沉淀，进一步确定了两者之间的相互作用。有研究表明PINK1突变可导致-synuclein表达量的上调和在细胞内的聚集。在本室成功干扰掉PINK1的MN9D细胞株中，我们检测到-synuclein的蛋白水平是明显增加的。此外，利用本室收集的表达-synuclein的逆转录病毒上清感染MN9D细胞，实时定量检测证明-synuclein的基因表达量显著上调，我们发现该种细胞中PINK1的蛋白水平是明显增加的。这些结果证明PINK1与-synuclein在细胞中能够共定位并相互作用，并能相互影响细胞

33、中的蛋白水平。这可能为PD相关基因的关系及机制研究提供一定的依据。Parkinsons Disease (PD) is a neurodegenerative disorder with pathological hallmarks of dopaminergic neuron degeneration in the substantia nigra pars compacta and cytoplasmic inclusion Lewy bodies that contain -synuclein, PINK1. The PD pathogenic pathways involve defe

34、cts in many cellular processes such as protein degradation, oxidative stress, phosphorylation signaling, and mitochondrial function. -synuclein and PINK1 are both implicated in genetic forms of familial PD. They both can localize to mitochondria, and their mutations have been shown to disrupt mitoch

35、ondrial fuction. Despite this wealth of evidence, its still unclear whether -synuclein and PINK1 have relationship between each other.To answer this question we first detected the location of -synuclein and PINK1 in MN9D cells by immunohistochemical staining. We found that they could be partly co-lo

36、calized in cytoplasm. This provided the possibility that they can interact with each other. We constructed the pcDNA3-Flag-PINK1 (G309D, C145, N35) eukaryotic expression vectors encoding wild-type and its mutants for further research. The GST-synuclein fusion protein was expressed in Escherichia col

37、i and purified on Glutathione-Sepharose 4B by standard methods, and incubated with MN9D cells lysate to detect the interaction of PINK1 with -synuclein. In addition, the full length of PINK1 robustly associated with -synuclein was determined by immunoprecipitation experiment in MN9D cells. We detect

38、ed that GST-synuclein interacted specifically with PINK1, but not GST. Immunoprecipitation with an anti-synuclein antibody and subsequent Western Blotting with an anti-PINK1 antibody confirmed the specific interaction of -synuclein with PINK1. We transiently transfected myc-synuclein/pCMV-myc or pcD

39、NA3-Flag-PINK1/pcDNA3-Flag into 293T cells respectively, and then repeated the immunoprecipitation with anti-myc or anti-Flag M2 affinity gel. The results confirmed the association of PINK1 and -synuclein.It has been proved that PINK1 mutations can upregulate the expression of -synuclein and induce

40、its aggregation. We found that MN9D cells knock-down PINK1 increased -synuclein protein level while overexpression of -synuclein evaluated the protein level of PINK1.These finds indicate that PINK1 and -synuclein can co-localize in cytoplasm and interact with each other, and they also can affect eac

41、h other at protein level.聚酰胺-胺树枝状分子修饰的硅壳荧光磁性纳米粒赵焕瑛 硕士 2009 人类脑部疾患的发病率正呈逐年上升的趋势，对人类生命和健康造成严重的危害。由于血脑屏障( blood brain barrier, BBB) 的存在，使脑部疾病无论采取基因治疗还是药物治疗都很难使有效成分导入中枢神经系统发挥作用。目前,探索利用载体经血管途径透过BBB治疗脑部疾病成为研究的热点。在协助药物或基因入脑的方法中，磁性纳米载体(又称磁纳米粒，magnetic nanoparticles，MNP)因其既具有纳米材料的特性，又具有磁响应性及超顺磁性，而且，这类药物载体还能延

42、缓药物在脑内的释放，降低外周毒性。因此，成为最有前景的靶向性药物或基因载体。本课题设计了聚酰胺-胺(PAMAM)树状分子修饰的可荧光示踪的硅壳磁性纳米载体作为治疗中枢神经系统疾病的药物或基因载体。该载体不仅具有荧光性、超顺磁性等特点，其外表面由于有PAMAM树状分子覆盖，具有大量官能团可再进一步修饰(如连接跨膜肽TAT、抗体、受体等)，而且能阻止包埋的荧光分子泄露所带来的毒副作用。本论文对所制备的系列载体进行了体内外的分布、毒性及穿越BBB能力评估，同时筛选出可携带基因的纳米载体。主要研究内容如下： (1) A549 和9L细胞吞噬纳米粒的体外实验：首次对纳米粒进入胶质瘤9L细胞、人肺腺癌A5

43、49细胞的能力、机制及细胞内定位进行了研究。由流式细胞计数结果可知，纳米粒进入细胞的能力呈时间和浓度依赖性，且受表面电荷影响。细胞经DAPI、Lysotracker blue染色结果表明纳米粒主要分布于胞浆中，且能被溶酶体俘获。细胞加入450mM蔗糖和0.2mg/mL 木黄酮两种抑制剂来观察细胞摄取纳米粒的机制，结果证明A549细胞吞噬纳米粒可通过网格蛋白有被小窝介导的内吞及细胞膜穴样内陷介导的内吞两种途径。9L细胞主要通过细胞膜穴样内陷介导的内吞途径。透射电镜结果验证了纳米粒进入细胞是通过胞吞作用完成的，且主要分布在细胞浆，而带有PEG作连接臂的，及整代PAMAM分子修饰的，纳米粒更易进入细

44、胞核。CCK-8毒性实验证实四种纳米粒毒性都很小，但PAMAM修饰后毒性更小，尤其PAMAM(G2.5)修饰的对细胞活力的影响最小。(2) 体内分布、毒性及跨血脑屏障能力评估实验：通过颈总动脉将四种纳米粒分别注射入大鼠体内，在激光共聚焦显微镜下观察各器官中纳米粒分布情况，并进行组织病理学HE染色分析。结果证明四种纳米粒都在脑组织分布，但只有PEG-PAMAM(G2)修饰的纳米粒分布的最多且聚集最少，其次为ICP-PAMAM(G2)修饰的纳米粒，且四种纳米粒都集中分布在网状内皮系统(RES)丰富的器官：肝脏、脾脏及肺脏。接着我们又将PEG-PAMAM(G2)修饰的纳米粒从ICR小鼠尾静脉进行注射

45、研究，通过行为学、血清生化分析、血液学分析及组织病理学分析表明：纳米粒可分布在全身各器官，且能穿越血脑屏障和血睾屏障，可通过尿液代谢排除，同时表明纳米粒对小鼠没有急性毒性作用。(3) 硅壳荧光纳米粒携基因能力及转染功能的评价：体外进行了纳米粒与DNA结合实验、纳米粒/DNA复合物抵抗DNase和血清消化实验及在Cos7细胞中基因转染等实验，结果表明只有PAMAM(G2)修饰的纳米粒才具有携带DNA能力并能抵御核酸酶和血清的消化，PAMAM(G2)修饰的硅壳荧光纳米粒携带的pDRsed monomer 基因在Cos7细胞中都表达了红色荧光蛋白。本课题设计合成的目标载体及其进入血脑屏障的研究未见文

46、献报道，结果表明PAMAM(G2)修饰纳米粒不但可以穿越血脑屏障,而且容易被神经元和胶质细胞摄取。本研究结果为PAMAM修饰的硅壳荧光纳米粒作为药物/基因载体，用于脑部疾病的治疗提供了基础研究数据，因而具有理论研究价值和潜在的应用价值。The diseases in human brain are rapidly increasing and threatening human health. The existence of BBB blocks most drugs or gene from entering the brain via blood system in the treatm

47、ent of neurological or psychiatric disorders of central nervous system (CNS). Now more interests in drug carriers have been focused on treating CNS disease through intravascular ways. Among various strategies aimed to enhance the penetration of drugs or gene carrier into the brain tissue, magnetic n

48、anoparticles (MNPs) have become a promising targeting carrier for drug or gene delivery through BBB. MNPs which have size in the scale of nanometer and possess unique superparamagnetism, have been shown to release drugs in a controlled manner and possess reduced peripheral toxicity. In this study, p

49、olyamidoamine (PAMAM) dendrimer conjugated fluorescein isothiocyanate (FITC)-doped silica-Fe3O4 core-shell magnetic nanoparticle has been developed as carrier for drug or gene delivery across the BBB. This carrier exhibits a unique superparamagnetism and can be traced by fluoresce as well. The conju

50、gation of PAMAM provides to the carrier a number of primary amino surface functional groups which allow it to conjugate additional ligands, such as transmembrane peptide TAT, appropriate receptors and antibody, to enhance the delivery of drug/gene to the targeting region. Furthermore, the capped PAM

51、AM might reduce the toxicity caused by the leakage of FITC. In this thesis, the in vivo and ex vivo pattern of distribution and toxicity of four kinds of nanoparticles and its ability to penetrate the BBB were investigated.Among them, nanoparticles which can carrier gene were choosen. These results

52、are shown as follows: (1) Examination of the cellular uptake of nanoparticles by 9L cells and A549 cells: The ability, mechanism and intracellular localization of the nanoparticles for 9L and A549 cells were evaluated. Flow cytometry analysis suggested the uptake process of the carrier by cells was

53、a time- and dose-dependent. The result also showed that the efficiency of intracellular uptake was affected by the surface charge of the particales, with the positive charge enhancing the uptake of cells. TEM studies have indicated that the nanoparticles were uptake by the cells through endocytosis.

54、Combined with the DAPI and lysotracker blue costaining result, nanoparticles were mostly internalized into cytoplasm with subsequent intracellular localization in late endosomes/lysosomes. Additional, Only PEG-PAMAM (G2) modified nanoparticles can be detected occassionaly in nucleus. To investigate

55、the possible mechanism of endocytosis of four kinds of nanoparticles, we tested the cellular uptake of nanoparticles in presence of specific inhibitors of different endocytotic pathways. Our results indicated that nanoparticles were endocytosed by A549 cell via a clathrin-pitted mechanism and a cavo

56、lar-mediated mechanism, as the uptakes were inhibited by 450mM sucrose and 0.2mg/ml genistein. However, the uptake efficiency of 9L cells was only affected by a caveolar inhibitor, genistein, suggesting that these nanoparticles are endocytosed via a caveolae-mediated mechanism.(2) Animal stuides of

57、the biodistribution, biocompatibility of nanoparticles and the ability of crossing the BBB: Four kinds of nanoparticles were infused in rats through carotid artery. Subsequently, the biodistribution of nanoparticles in tissue slices stained with DAPI were investigated by confocal laser scanning micr

58、oscope (CLSM). Histopathological analysis in various organs was observed in tissue slices stained with hematoxilin and eosin (HE). HE result showed that no abnomal histopathological changes were observed. CLSM result showed that four type of nanoparticles all were found in the brain, but PEG-PAMAM(G

59、2) modified nanoparticles were distributed more widespread and lesser accumulative than other nanoparticles. Besides, nanoparticles were also found in the organs with plenty of reticulo endothelial system (RES), such as liver, spleen and lung. At the same time FMNPs-PEG-PAMAM (G2) were injected intravenously via the tail vein of mice at a dose of 10 mg /kg. The in vivo toxicity was evaluated. The results of serum biochemical analysis, hema