去唾液酸糖蛋白受体介导的肝靶向研究进展

目的 介绍去唾液酸糖蛋白受体(asialoglycoprotein receptor,ASGPR)介导的药物和基因肝靶向作用和机制,及其在治疗肝癌和乙型肝炎实验研究方面的最新进展。方法 查阅和选取针对性强、相关度高的文献,总结和归纳ASGPR介导的药物和基因肝靶向用于治疗肝癌和乙型肝炎的最新研究进展。结果 ASGPR是肝细胞的一种重要且高效的内吞受体,可用于介导药物和基因的肝靶向递送。结论 ASGPR介导的药物和基因肝靶向有望成为肝癌和乙型肝炎治疗的有效手段。     

基于去唾液酸糖蛋白受体的肝靶向药物的研究

去唾液酸糖蛋白受体(asialoglycoprotein receptor, ASGPR)是一种在肝实质细胞表面高度表达的受体,它可以特异性识别和结合末端带有半乳糖或N-乙酰基半乳糖胺残基的分子,通过网格蛋白介导其内吞并转运至溶酶体中降解。基于这一特性, ASGPR介导的肝靶向药物递送会增加药物在肝脏中的分布、减少药物潜在不良反应并降低给药剂量。本文全面综述了ASGPR的表达、组成与结构、结合及内吞,系统总结了基于ASGPR的配体设计、优化及其释放策略,并展望该受体在药物开发中的应用。     

受体介导的肝靶向载药系统研究进展

介绍近几年已报道的有关受体介导的肝靶向载药系统的研究情况。近年来受体介导的肝靶向载药系统的研究取得了一些可喜进展,相关配体-受体可与药物、脂质体、纳米粒、基因、偶联物等相连,提高药物或载体的肝靶向能力。受体介导机制在肝靶向载药系统的研究领域具有广阔的应用前景,尤其是肝脏特异性受体的不断发掘,丰富了肝主动靶向的理论体系,展示了肝脏疾病治疗的美好未来。     

肝靶向药物的研究进展

综述肝靶向药物的研究进展.治疗性的肝靶向药物有毫微粒及微球制剂、免疫导向药物、糖蛋白受体导向药物、信号靶向药物、肝靶向降胆固醇药物、抗疟药及促骨骼生长药等;诊断性的肝靶向药物有磁性毫微粒、无唾液酸糖蛋白受体介导的肝靶向药物等.肝靶向药物的研究开发,为肝脏疾病及其相关疾病的诊断和治疗开辟了广阔的前景.     

去唾液酸糖蛋白受体（ASGPR）在N-二硝基亚乙胺诱导原位肝癌模型、原位移植肝癌模型大鼠体内的表达与分布

目的 测定去唾液酸糖蛋白受体(ASGPR)在N-二硝基亚乙胺(DEN)诱导大鼠原位肝癌模型(DEN-HCC-Rat)和原位移植大鼠肝癌模型(OTT-HCC-Rat)中的表达。方法 DEN-HCC-Rat造模:模型组SD大鼠按照20 mg·kg^-1 ig 0.25% DEN水溶液,每周1次,0.025% DEN水溶液供动物饮用;对照组每周ig 1次0.9%氯化钠溶液,灭菌水供动物饮用,于造模第4、10、18、22周取材。OTT-HCC-Rat造模:模型组SD大鼠肝叶注射N1-S1细胞,假手术组大鼠麻醉后给予微创缝合处理,于注射后14 d取材。HE染色观察肝组织病变;通过免疫组化、免疫荧光、Western blotting和实时荧光定量PCR(qRT-PCR)实验检测各组ASGPR表达及分布。结果 通过HE染色确定DEN-HCC-Rat和OTT-HCC-Rat造模成功。在DEN-HCC-Rat中,免疫组化、免疫荧光、Western blotting、qRT-PCR结果均显示,与对照组比较,模型组大鼠肝组织ASGPR表达显著上调(P＜0.05、0.01),且呈时间相关性;在OTT-HCC-Rat中,免疫组化结果显示模型组ASGPR表达显著高于假手术组(P＜0.05),免疫荧光、Western blotting、qRT-PCR结果显示ASGPR在模型组与假手术组之间无显著性差异。结论 DEN-HCC-Rat模型更好地模拟肿瘤微环境改变,且ASGPR在肝癌区域表达高于对照组大鼠肝脏,故可利用ASGPR介导肝靶向制剂的转运,提高肝靶向药物治疗效果。     

半乳糖多聚赖氨酸的肝靶向特征

以还原胺化法合成了半乳糖多聚-L-赖氨酸(GalPLL), 并首次利用放射性示踪实验测定了GalPLL在小鼠体内的肝靶向特征. 结果表明, GalPLL具有较高的肝靶向性, 其在体内的分布形式与肝细胞去唾液酸糖蛋白受体(ASGPR)的内源性配体去唾液酸胎球蛋白(ASF)相似. ¹²⁵I标记的GalPLL经静脉注入小鼠体内后, 主要被肝脏吸收, 在注射后5 min时肝脏的最大吸收为注射总量的38.9%, 比人血清白蛋白高5.7倍. 肝脏对GalPLL的吸收可特异地被ASF及非标记的GalPLL抑制, 但不能被未半乳糖基化的多聚-L-赖氨酸抑制, 证明GalPLL是通过肝细胞ASGPR介导的内吞作用特异地被肝脏吸收的. 由于GalPLL不但具有较高的肝靶向性,而且与ASGPR的天然配体相比在合成和应用方面均具有许多优势, 因此有望成为进行药物或基因肝靶向运送的良好载体.     

短肽在靶向药物递送系统中的研究进展

近年来研究发现许多肿瘤细胞表面高表达一些肽类受体，这些肽类受体与相应的配体亲和性高，能以配体-受体方式特异性结合。以小片段活性肽作为导向物形成复合物而发展的靶向药物递送系统，能够将药物定向转运到靶细胞内，显示了良好的研究价值和应用前景。如蛙皮素/胃泌素释放肽受体介导的靶向药物递送系统、生长抑素受体介导的靶向药物递送系统、十肽SynB₃受体介导的靶向药物递送系统、黄体酮释放激素受体介导的靶向药物递送系统及其他肽类受体介导的靶向药物递送系统，其中短肽作为靶向基团与阿霉素、吡咯阿霉素、甲氨蝶呤、顺铂和喜树碱等结合形成高效的复合物，用于表达有相应受体的肿瘤，获得靶向治疗的研究非常有意义。     

肿瘤靶向治疗药物研究进展

近年来,随着分子生物学技术的提高及从细胞受体和增殖调控的分子水平对肿瘤发病机制的进一步认识,开始了针对细胞受体、关键基因和调控分子为靶点的治疗,即“靶向治疗”.所谓靶向药物治疗就是使药物瞄准肿瘤部位,在局部保存相对较高的浓度,延长药物作用时间,提高对肿瘤细胞的杀伤力,但对正常组织细胞作用较小.目前,用于肿瘤靶向治疗的药物有控缓释化疗药、脂质体化疗药、分子靶向药物、放射性核素等,药物可通过多途径给予,如血管介入给药、超声介导靶向经皮给药等。     

无唾液酸糖蛋白受体介导的肝靶向药物

将肝细胞膜上无唾液酸糖蛋白受体所能识别的配基体为载体与药物相结合获得肝靶向药物，本文着重介绍无唾液酸糖蛋白受体介导的肝靶向药物的作用机制，药物载体及应用。     

叶酸受体介导的靶向给药研究进展

叶酸受体可以与叶酸及其类似物特异性结合,通过介导细胞内化将其摄入细胞胞浆。利用叶酸受体在肿瘤和关节炎细胞的过度表达,使药物与叶酸结合,以叶酸受体为作用靶点,即可将药物主动靶向肿瘤和关节炎细胞,从而提高药物在肿瘤、关节炎的组织分布,达到靶向诊断、治疗的目的。本文就叶酸受体及其组织分布,叶酸受体介导的内吞作用,叶酸受体介导的肿瘤和关节炎的靶向诊断、治疗的研究进展进行了综述。     

Targeted delivery of macromolecular drugs: asialoglycoprotein receptor (ASGPR) expression by selected hepatoma cell lines used in antiviral drug development

The asialoglycoprotein receptor (ASGPR), an endocytotic cell surface receptor expressed by hepatocytes, is triggered by triantennary binding to galactose residues of macromolecules such as asialoorosomucoid (ASOR). The capacity of this receptor to import large molecules across the cellular plasma membrane makes it an enticing target for receptor-mediated drug delivery to hepatocytes and hepatoma cells via ASGPR-mediated endocytosis. This study describes the preparation and characterization of (125)I-ASOR, and its utility in the assessment of ASGPR expression by HepG2, HepAD38 and Huh5-2 human hepatoma cell lines. ASOR was prepared from human orosomucoid, using acid hydrolysis to remove sialic acid residues, then radioiodinated using iodogen. (125)I-ASOR was purified by gel column chromatography and characterized by SDS-PAGE electrophoresis. The ASOR yield by acid hydrolysis was 75%, with approximately 87 % of the sialic acid residues removed. Electrophoresis and gel chromatography demonstrated substantial differences in (125)I-ASOR quality depending on the method of radioiodination. ASGPR densities per cell were estimated at 76,000 (HepG2), 17,000 (HepAD38) and 3,000 (Huh-5-2). (125)I-ASOR binding to ASGPR on HepG2 cells was confirmed through galactose- and EDTA- challenge studies. It is concluded that (125)I-ASOR is a facilely-prepared, stable assay reagent for ASGPR expression if appropriately prepared, and that HepG2 cells, but not HepAD38 or Huh-5-2 cells, are suitable for studies exploiting the endocytotic ASGPR.     

Asialoglycoprotein receptor-targeted superparamagnetic iron oxide nanoparticles

Superparamagnetic iron oxide (SPIO) nanoparticles are primarily used as contrast agents in magnetic resonance imaging. SPIO have also been derivatized to add targeting and drug-carrier functionality as drug delivery devices. The preparation and characterization of amino-functionalized SPIO (ASPIO) and lactose-derivatized galactose-terminal-ASPIO are now reported. The target for galactose-terminal-ASPIO is the cell-surface asialoglycoprotein receptor (ASGPR) expressed by hepatocytes. Two batches of ASPIO with average particle sizes of 61 [42]nm and 127 [125]nm [full-width half maximum; FWHM] were prepared. The small ASPIO increased from 61 nm to 278 [309]nm upon lactosylation (Gal-ASPIO-278) and to 302 [280] by N-acetylation (NAcASPIO-302); the larger ASPIO afforded galactosyl-terminal ASPIO of 337 [372]nm and N-acetylated ASPIO of 326 [308]nm. The LD50 of Gal-ASPIO-278 was 1500 microg/mL to HepG2 cells; Gal-ASPIO-278 associated with HepG2 cells in vitro, whereas NAcSPIO-302, prepared from the same ASPIO batch, did not. Gal-ASPIO-278 and NAcASPIO-302 were not bound by ASPGR non-expressing 143B cells. The association of Gal-ASPIO-278 to HepG2 cells was reduced by free galactose, supporting the model of ASGPR-mediated binding. These data underline the potential application of Gal-ASPIO as a targeted ligand for ASPGR-expressing cells in vivo.     

Liver targeting characteristics of galactosyl poly L lysine

以还原胺化法合成了半乳糖多聚－Ｌ－赖氨酸（ＧａｌＰＬＬ）,并首次利用放射性示踪实验测定了ＧａｌＰＬＬ在小鼠体内的肝靶向特征．结果表明,ＧａｌＰＬＬ具有较高的肝靶向性,其在体内的分布形式与肝细胞去唾液酸糖蛋白受体（ＡＳＧＰＲ）的内源性配体去唾液酸胎球蛋白（ＡＳＦ）相似．１２５Ｉ标记的ＧａｌＰＬＬ经静脉注入小鼠体内后,主要被肝脏吸收,在注射后５ｍｉｎ时肝脏的最大吸收为注射总量的３８．９％,比人血清白蛋白高５．７倍．肝脏对ＧａｌＰＬＬ的吸收可特异地被ＡＳＦ及非标记的ＧａｌＰＬＬ抑制,但不能被未半乳糖基化的多聚－Ｌ－赖氨酸抑制,证明ＧａｌＰＬＬ是通过肝细胞ＡＳＧＰＲ介导的内吞作用特异地被肝脏吸收的．由于ＧａｌＰＬＬ不但具有较高的肝靶向性,而且与ＡＳＧＰＲ的天然配体相比在合成和应用方面均具有许多优势,因此有望成为进行药物或基因肝靶向运送的良好载体．     

Nanoparticles for human liver-specific drug and gene delivery systems: in vitro and in vivo advances

A wide variety of nanoparticles (NPs) that can deliver incorporated therapeutic materials such as compounds, proteins, genes and siRNAs to the human liver have been developed to treat liver-related diseases. This review describes NP-based drug and gene delivery systems such as liposomes (including lipoplex), polymer micelles, polymers (including polyplex) and viral vectors. It focuses upon the modification of these NPs to enhance liver specificity or delivery efficiency in vitro and in vivo. We discuss recent advances in drug and gene delivery systems specific to the human liver utilizing bio-nanocapsules comprising hepatitis B virus (HBV) envelope L protein, which has a pivotal role in HBV infection. These NP-based medicines may offer novel strategies for the treatment of liver-related diseases and contribute to the development of nanomedicines targeting other tissues.     

Asialoglycoprotein receptor targeted delivery of doxorubicin nanoparticles for hepatocellular carcinoma

We report asialoglycoprotein receptor (ASGPR)-targeted doxorubicin hydrochloride (Dox) nanoparticles (NPs) for hepatocellular carcinoma (HCC). Polyethylene sebacate (PES)-Gantrez® AN 119 Dox NPs of average size 220?nm with PDI?p?相似文献   

Lectin recognition and hepatocyte endocytosis of GalNAc-decorated nanostructured lipid carriers

Abstract

Liver is the main organ for metabolism but is also subject to various pathologies, from viral, genetic, cancer or metabolic origin. There is thus a crucial need to develop efficient liver-targeted drug delivery strategies. Asialoglycoprotein receptor (ASGPR) is a C-type lectin expressed in the hepatocyte plasma membrane that efficiently endocytoses glycoproteins exposing galactose (Gal) or N-acetylgalactosamine (GalNAc). Its targeting has been successfully used to drive the uptake of small molecules decorated with three or four GalNAc, thanks to an optimisation of their spatial arrangement. Herein, we assessed the biological properties of highly stable nanostructured lipid carriers (NLC) made of FDA-approved ingredients and formulated with increasing amounts of GalNAc. Cellular studies showed that a high density of GalNAc was required to favour hepatocyte internalisation via the ASGPR pathway. Interaction studies using surface plasmon resonance and the macrophage galactose-lectin as GalNAc-recognising lectin confirmed the need of high GalNAc density for specific recognition of these NLC. This work is the first step for the development of efficient nanocarriers for prolonged liver delivery of active compounds.     

乳糖化赖氨酸与反义x基因质粒复合物体外对HBV表达的抑制

目的研制一种能把基因药物定向导入肝脏组织的小分子肝靶向药物载体。方法用还原氨化法合成乳糖化赖氨酸(Lac-Lys)共价结合物作为肝靶向药物载体。将含HBV反义x基因的质粒在一定条件下与Lac-Lys制成复合物后转染HepG2.2.15。用酶联免疫吸附试验(ELISA)检测细胞培养上清中的HBsAg和HBeAg。结果经红外光谱定性,成功制备出了Lac-Lys的共价结合物;此共价结合物能与质粒DNA形成复合物,经细胞培养观察可将质粒DNA载入细胞;抗原检测结果显示,含有反义xDNA的质粒在细胞内能有效抑制病毒的复制。xDNA与Lac-Lys的最佳比例是1∶5,最大抑制率是73.2%。结论合成的Lac-Lys可将反义x基因质粒定向载入细胞内,并有效抑制HBsAg和HBeAg的表达。     

Targeting C-type lectin receptors with multivalent carbohydrate ligands

C-type lectin receptors (CLRs) represent a large receptor family including collectins, selectins, lymphocyte lectins, and proteoglycans. CLRs share a structurally homologous carbohydrate-recognition domain (CRD) and often bind carbohydrates in a Ca^2 +-dependent manner. In innate immunity, CLRs serve as pattern recognition receptors (PRRs) and bind to the glycan structures of pathogens and also to self-antigens. In nature, the low affinity of CLR/carbohydrate interactions is overcome by multivalent ligand presentation at the surface of cells or pathogens. Thus, multivalency is a promising strategy for targeting CLR-expressing cells and, indeed, carbohydrate-based targeting approaches have been employed for a number of CLRs, including asialoglycoprotein receptor (ASGPR) in the liver, or DC-SIGN expressed by dendritic cells. Since CLR engagement not only mediates endocytosis but also influences intracellular signaling pathways, CLR targeting may allow for cell-specific drug delivery and also the modulation of cellular functions. Glyconanoparticles, glycodendrimers, and glycoliposomes were successfully used as tools for CLR-specific targeting. This review will discuss different approaches for multivalent CLR ligand presentation and aims to highlight how CLR targeting has been employed for cell specific drug delivery. Major emphasis is directed towards targeting of CLRs expressed by antigen-presenting cells to modulate immune responses.     

Characteristics and biodistribution of soybean sterylglucoside and polyethylene glycol-modified cationic liposomes and their complexes with antisense oligodeoxynucleotide

A novel cationic liposome modified with soybean sterylglucoside (SG) and polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE) as a carrier of antisense oligodeoxynucleotide (ODN) for hepatitis B virus (HBV) therapy was constructed. Characteristics of the cationic liposomes modified with SG and PEG (SG/PEG-CL) and their complexes with 15-mer phosphorothioate ODN (SG/PEG-CL-ODN complex) were investigated by incorporation efficiency, morphology, electrophoresis, zeta potentials, and size analysis. Antisense activity of the liposomes and ODN complexes was determined as hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in HepG₂ 2.2.15 cells by ELISA. Their tissue and intrahepatic distribution were evaluated following intravenous injection in mice. The complexes gained high incorporation efficiency and intact vesicular structure with mean size at ∼200 nm. The SG/PEG-CL-ODN complexes enhanced the inhibition of both HBsAg and HBeAg expression in the cultured HepG₂ 2.2.15 cells relative to free ODN. The uptake of SG/PEG-CL and nonmodified cationic liposomes (CL) was primarily by liver, spleen, and lung. Furthermore, the concentration of SG/PEG-CL was significant higher than that of CL in hepatoctyes at 0.5 hr postinjection. The biodistribution of SG/DSPE-CL-ODN complex compare with free ODN showed that liposomes enhanced the accumulation of ODN in the liver and spleen, while decreasing its blood concentration. SG/PEG-CL-mediated ODN transfer to the liver is an effective gene delivery method for cell-specific targeting, which has a potential for gene therapy of HBV infections. SG and PEG-modified cationic liposomes have proven to be an alternative carrier for hepatocyte-selective drug targeting.