PTP-1B及其抑制剂与2型糖尿病的研究现状

蛋白酪氨酸磷酸酶-1B (PTP-1B)是蛋白酪氨酸磷酸酶(PTP)家族中的一员,在胰岛素信号转导途径中发挥重要作用.经研究发现,PTP-1B与2型糖尿病的发生、发展有密切关系. 本文按PTP-1B 小分子抑制剂的结构类别对近年来文献报道的代表性小分子PTP-1B 抑制剂进行综述.表明深入研究PTP-1B及其有效的抑制剂对于2型糖尿病治疗具有良好的发展前景.     

蛋白酪氨酸磷酸酶1B小分子抑制剂的研究进展

蛋白酪氨酸磷酸酶IB（PTP-1B）是胰岛素和瘦索信号转导通路的负调节因子。小鼠PTP-1B基因敲除及反义核苷酸治疗实验表明PTP-1B是治疗糖尿病和肥胖症的潜在靶标。按PTP-1B小分子抑制剂的结构类别对近年来文献报道的代表性小分子PTP-1B抑制剂进行综述。指出采用小分子抑制PTP-1B酶可能成为治疗胰岛素抵抗、2型糖尿病以及肥胖症的新途径。     

蛋白酪氨酸磷酸酶1B及其小分子抑制剂的研究进展

蛋白酪氨酸磷酸酶1B（PTP-1B）是胰岛素和瘦素信号传导通路的负调节因子。目前,作为糖尿病和肥胖症治疗的新靶点,PTP-1B抑制剂的研究引起了广泛的关注。现从PTP-1B简介、生理功能以及抑制剂的结构性质等方面进行综述。     

扫描新的药物分子

蛋白酪氨酸磷酸酶抑制剂蛋白酪氨酸磷酸酶(PTP)和酪氨酸激酶调节蛋白酪氨酸磷酸化水平,成为控制细胞内信号转导通路的关键机制之一。有多种疾病与不能调节磷酸酶的活性有关,例如PTP-α和Cdc25磷酸酶提示可能与癌变有关。故这些酶成为令人感兴趣的治疗靶标。合成PTP抑制剂的一种方法是针对一种特异PTP设计有选择性的抑制剂,但所有PTP催化机制相同,高活性位点也相同,故较难达到。但与PTP1B结合的双配体化合物及3位点结合化合物有一定活性。基于基本结构(1),用液相法合成了104个化合物库。用未纯化的鼠疫耶尔森菌(Yersiniapestis)PTP…     

蛋白酪氨酸磷酸酶-1B抑制剂的研究进展

目的：介绍近年来研究的各种蛋白酪氨酸磷酸酶-1B(protein tyrosine phosphatase 1B，PTP-1B)抑制剂的作用机制和特性。方法：查阅关于PTP-1B抑制剂的国外文献，探讨产生抑制作用的机制。结果：PTP-1B是瘦素和胰岛素信号转导的主要负性调节者，目前所研究的PTP-1B抑制剂能有效抑制PTP-1B；某些还具有良好的脂溶性，可渗透人细胞发挥作用。结论：PTP-1B抑制剂用于治疗糖尿病和肥胖具有重要价值。     

以PTP1B为靶点的胰岛素增敏剂的实验研究

蛋白酪氨酸磷酸酶1B（protein tyrosine phosphatase 1B，PTP1B）是蛋白酪氨酸磷酸酶家族中的主要成员之一，在胰岛素信号传导系统的平衡中，起着重要作用。胰岛素信号传导系统主要是通过信号分子的磷酸化程度来调节的。信号分子的酪氨酸磷酸化与去磷酸化的平衡，对胰岛素发挥生物效应极其重要。阿PTP1B是催化分子酪氨酸去磷酸化的蛋白酪氨酸磷酸酶家族中的主要成员之一，可以使胰岛素受体底物（IRSs）等许多信号分子的酪氨酸去磷酸化而失活，在胰岛素信号传导系统中起着重要作用。阿PTP1B抑制剂已成为胰岛素增敏剂的靶点之一。     

蛋白酪氨酸磷酸酶：治疗前景

蛋白酪氨酸磷酸酶（PTP）大家族，是信号转导途径中的重要调节因子。最近的小鼠基因敲除实验发现，PTP1B极有希望成为开发抗糖尿病／肥胖症药物的作用靶点。PTP也参与体内包括癌症在内的多种疾病的病理过程。特异抑制单个PTP同工酶活性的小分子物质得以鉴定，并取得重要进展。本文概述PTP的基本结构、作用特征及其在信号转导途径中的地位，并对其小分子抑制剂的治疗用途作一展望。     

虚拟筛选荭草素和异荭草素降血糖靶点和体外活性评价

目的 研究荭草素和异荭草素降血糖的靶点及其体外活性。方法 从蛋白质数据库（www.rcsb.org）获取糖尿病相关靶点蛋白结构,利用虚拟分子对接打分评价荭草素和异荭草素与糖尿病相关靶点的结合强弱;基于分子对接的结果,采用荧光标记的1-脱氧葡萄糖（1-NBDG）、4-硝基苯基-α-D-葡萄糖苷PNDG(PNPG)、对硝基苯酚磷酸酯（pNPP）作为底物对荭草素和异荭草素进行体外抑制α-葡萄糖糖苷酶、钠–葡萄糖协同转运蛋白2(SGLT2)和蛋白酪氨酸磷酸酶1B(PTP1B)活性评价。结果 荭草素与α-葡萄糖苷酶、SGLT2、和PTP1B的分子对接得分分别为-5.67、-9.32、-4.75,异荭草素与α-葡萄糖苷酶、SGLT2和PTP1B的分子对接得分分别为-5.34、-8.63、-4.93,而阳性对照药与靶标的分子对接打分依次是-5.58、-9.79、-9.28。体外实验显示,荭草素对α-葡萄糖苷酶、SGLT2、PTP1B的抑制率依次是（16.7±5.8）%、（15.4±1.2）%、（3.0±0.5）%,异荭草素对α-葡萄糖苷酶、SGLT2、PTP1B的抑制率依次是（11.8±3.8）%、...     

异槲皮苷调控PTP1B改善胰岛素抵抗的网络药理学研究及体外实验验证

目的 采用网络药理学法及分子对接技术探析异槲皮苷改善胰岛素抵抗的分子机制,并通过体外实验研究异槲皮苷对胰岛素抵抗的干预作用及机制。方法 利用PubChem、PharmMapper、GEO、CTD、GeneCards、OMIM等多个数据库筛选异槲皮苷活性成分及胰岛素抵抗相关靶点;采用Cytoscape软件将异槲皮苷治疗胰岛素抵抗的潜在靶点构建蛋白质相互作用（PPI）网络,并根据度值筛选核心靶点。利用基因本体（GO）与京都基因与基因组百科全书（KEGG）富集分析寻找与靶点蛋白相关的生物学通路,采用AutoDock Tools软件模拟分子对接,预测异槲皮苷与关键靶点的结合度。体外实验采用异槲皮苷干预蛋白酪氨酸磷酸酶1B（PTP1B）质粒转染HepG2细胞,检测不同浓度异槲皮苷干预后PTP1B的活性;构建PTP1B质粒转染HepG2胰岛素抵抗细胞模型,给予异槲皮苷（40μmol/L）干预,葡萄糖氧化酶法、qRT-PCR、Western Blotting法检测PTP1B等相关因子的表达。结果 网络药理学筛选得到异槲皮苷改善胰岛素抵抗的交集靶点21个,富集到GO条目2 761个,主要涉及胰岛素受体信号通路、糖原生物合成过程的调控等,富集到KEGG通路89条,涉及包括胰岛素信号通路、胰岛素抵抗、磷脂酰肌醇-3-羟激酶（PI3K）-蛋白激酶B（Akt）信号通路、磷酸腺苷活化的蛋白激酶（AMPK）信号通路等。分子对接结果显示,异槲皮苷与靶点PTP1B、磷酸肌醇依赖性蛋白激酶1（PDPK1）、胰岛素受体（INSR）、糖原合酶激酶3β（GSK3β）、AKT2均有一定的结合活性。体外实验结果显示,异槲皮苷能有效抑制PTP1B活性,降低PTP1B过表达HepG2胰岛素抵抗细胞中PTP1B、GSK3β的表达,升高胰岛素受体底物1（IRS-1）、葡萄糖转运蛋白-1（GLUT-1）等因子的表达,改善细胞胰岛素抵抗。结论 异槲皮苷可能通过抑制PTP1B调控PI3K/Akt信号通路因子活性改善胰岛素抵抗。     

溴酚衍生物的合成及其蛋白酪氨酸磷脂酶1B抑制活性研究

目的合成具有新型结构的系列溴酚衍生物,测试其体外蛋白酪氨酸磷脂酶1B(PTP1B)抑制活性并初步探讨其构效关系。方法以香草醛或3,4-二羟基苯甲醛为原料,经溴化、还原、醚化等反应制得目标化合物。借助重组人源PTP1B蛋白水解底物p NPP的方法,测定目标物对PTP1B的抑制活性。结果合成了18个溴酚衍生物,其结构经EI-MS、ESI-MS、~1H-NMR、~(13)C-NMR谱确证。结论目标化合物的PTP1B抑制活性与化合物中溴原子的数目、位置以及烷基链的长度有关;化合物6c体外PTP1B抑制活性最好(IC50=0.572μmol·L~(-1))。     

Protein tyrosine phosphatase-1B in diabetes

A role for protein tyrosine phosphatases in the negative regulation of insulin signaling and a putative involvement in the insulin resistance associated with type 2 diabetes have been postulated since their discovery. The recent demonstration that mice lacking the protein tyrosine phosphatase-1B (PTP-1B) have enhanced insulin sensitivity validates this. Furthermore, when fed a high fat diet, these mice maintained insulin sensitivity and were resistant to obesity, suggesting that inhibition of PTP-1B activity could be a novel way of treating type 2 diabetes and obesity. This commentary reviews our current knowledge of PTP-1B in insulin signaling and its role in diabetes and discusses the development of potent and selective PTP-1B inhibitors.     

Discovery of a novel protein tyrosine phosphatase-1B inhibitor, KR61639: potential development as an antihyperglycemic agent

Protein tyrosine phosphatase-1B (PTP-1B), a negative regulator of insulin signaling, may be an attractive therapeutic target for type 2 diabetes mellitus. High throughput screening (HTS) for PTP-1B inhibitors using compounds from the Korea Chemical Bank identified several hits (active compounds). Among them, a hit with 1,2-naphthoquinone scaffold was chosen for lead development. KR61639, [4-[1-(1H-indol-3-yl)-3,4-dioxo-3,4-dihydro-naphthalen-2-ylmethyl]-phenoxy]-acetic acid tert-butyl ester, inhibited human recombinant PTP-1B with an IC(50) value of 0.65 microM in a noncompetitive manner. KR61639 showed modest selectivity over several phosphatases and increased insulin-stimulated glycogen synthesis in HepG2 cells and stimulated 2-deoxyglucose uptake in 3T3/L1 adipocytes. In addition, in vivo study using ob/ob mouse demonstrated that KR61639 exerted a hypoglycemic action when given orally. Thus, KR61639 may be a good starting point for lead optimization in developing a novel antidiabetic agent.     

Finding discriminating structural features by reassembling common building blocks

We present a new method for constructing discriminating substructures by reassembling common medicinal chemistry building blocks. The algorithm can be parametrized to meet differing objectives: (1) to build features that discriminate for biological activity in a local structural neighborhood, (2) to build scaffolds for R-group analysis, (3) to construct cluster signatures that discriminate for membership in the cluster and provide a graphical representation for its members, and (4) to identify substructures that characterize major classes in a heterogeneous compound set. We illustrated the results of the algorithm on a literature dataset is of 118 compounds with in vitro inhibition data against recombinant human protein tyrosine phosphatase 1B (PTP-1B).     

Current therapies and emerging targets for the treatment of diabetes

Concurrent with the spread of the western lifestyle, the prevalence of all types of diabetes is on the rise in the world's population. The number of diabetics is increasing by 4-5% per year with an estimated 40-45% of individual's over the age of 65 years having either type II diabetes or impaired glucose tolerance. Since the signs of diabetes are not immediately obvious, diagnosis can be preceded by an extended period of impaired glucose tolerance resulting in the prevalence of beta-cell dysfunction and macrovascular complications. In addition to increased medical vigilance, diabetes is being combatted through aggressive treatment directed at lowering circulating blood glucose and inhibiting postprandial hyperglycemic spikes. Current strategies to treat diabetes include reducing insulin resistance using glitazones, supplementing insulin supplies with exogenous insulin, increasing endogenous insulin production with sulfonylureas and meglitinides, reducing hepatic glucose production through biguanides, and limiting postprandial glucose absorption with alpha-glucosidase inhibitors. In all of these areas, new generations of small molecules are being investigated which exhibit improved efficacy and safety profiles. Promising biological targets are also emerging such as (1) insulin sensitizers including protein tyrosine phosphatase-1B (PTP-1B) and glycogen synthase kinase 3 (GSK3), (2) inhibitors of gluconeogenesis like pyruvate dehydrogenase kinase (PDH) inhibitors, (3) lipolysis inhibitors, (4) fat oxidation including carnitine palmitoyltransferase (CPT) I and II inhibitors, and (5) energy expenditure by means of beta 3-adrenoceptor agonists. Also important are alternative routes of glucose disposal such as Na+-glucose cotransporter (SGLT) inhibitors, combination therapies, and the treatment of diabetic complications (eg. retinopathy, nephropathy, and neuropathy). With may new opportunities for drug discovery, the prospects are excellent for development of innovative therapies to effectively manage diabetes and prevent its long term complications. This review highlights recent (1997-2000) advances in diabetes therapy and research with an emphasis on small molecule drug design (275 references).     

Patent focus on antidiabetic agents: September 1999 - February 2000

This focus highlights the most relevant patent disclosures in the field of oral antidiabetic therapy for the period of September 1999 to February 2000. As diabetes is a multi-faceted disease of decreased insulin secretion, increased peripheral (muscle, fat and liver) insulin resistance and dysregulated hepatic glucose production, recent drug development activities have centred around insulin secretagogues, insulin sensitisers and inhibitors of hepatic glucose output. Of particular note recently, are agents which increase insulin sensitivity (PPARγ and RXR agonists), modulate the insulin signalling pathway (PTP-1B and GSK-3 inhibitors), decrease hepatic gluconeogenesis and/or glycogenolysis (G6Pase, F1,6BPase and GP inhibitors), modulate glucose metabolism (PDHK inhibitors) and increase insulin secretion (DPP IV inhibitors).     

Real-time measurement in living cells of insulin-like growth factor activity using bioluminescence resonance energy transfer

Insulin-like growth factor (IGF)-I and -II function in normal physiology to control growth, development, and differentiation, but are also important in pathophysiological conditions, particularly in cancer. The biological effects of the IGFs are mediated by the IGF-I receptor (IGFR), a covalent homodimer composed of two alpha and two beta chains, similar in structure to the insulin receptor (IR). To allow measurement of the stimulation of IGFR in living cells, we developed an assay based on bioluminescence resonance energy transfer (BRET) between a donor molecule, Renilla luciferase, and an acceptor fluorophore, enhanced yellow fluorescent protein (EYFP). Initial attempts based on fusion of the luciferase to IGFR, and EYFP to IGFR, or to downstream signaling molecules, insulin receptor substrate-1 (IRS1) or protein tyrosine phosphatases-1B (PTP-1B), failed. However, similar experiments with IR, carried our in parallel, proved successful. We therefore, constructed assays based on chimeric IGFR/IR proteins, in which the ligand binding site was derived from IGFR. With the most efficient assay, in which the luciferase is fused to a chimeric receptor with the entire intracellular portion derived from IR, and EYFP fused to PTP-1B, IGF activity was measured specifically with sensitivity similar to the corresponding assay for insulin, based on IR. The established system allows efficient evaluation of candidate ligand- or receptor-directed molecules for the modulation of IGF activities. Furthermore, we demonstrate that a set of inhibitory IGF binding proteins (IGFBPs) or activating IGFBP-specific proteinases, unique to the IGF system, may serve as potential targets. In addition to screening, real-time measurement of IGFR stimulation may be important in efforts to understand the kinetics of receptor stimulation, in particular differences between IGFR and IR.