Protease Inhibitor Analogues for Enhanced Transport Across Blood-Brain Interfaces

蛋白酶抑制剂类似物可增强跨血脑界面的运输

基本信息

批准号：
7555598
负责人：
Ashim K. Mitra
金额：
$ 37.25万
依托单位：
UNIVERSITY OF MISSOURI KANSAS CITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-01-15 至 2011-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7555598
关键词：
AIDS Dementia Complex ATP-Binding Cassette Transporters Acquired Immunodeficiency Syndrome Affinity Amino Acid Transporter Amino Acids Amprenavir Anti-HIV Agents Applications Grants Astrocytes Binding Biological Availability Biotin Blood Blood - brain barrier anatomy Blood Circulation Brain Bypass CYP3A4 gene Capillary Endothelial Cell Cell Culture Techniques Cell Line Clinical Coculture Techniques Coupled Cultured Cells Diffusion Dipeptides Drug Kinetics Drug resistance Endothelial Cells Enzymes Exhibits Folate HIV HIV Protease Inhibitors Highly Active Antiretroviral Therapy Human In Vitro Intravenous Ligands Link Lipids Liver Microsomes Lopinavir Mediating Membrane Metabolic Metabolism Microdialysis Modeling Modification Multi-Drug Resistance N-glycylglutamic acid Natural regeneration Neuraxis Octanols Oral Oral Administration Outcome P-Glycoprotein P-Glycoproteins Partition Coefficient Patients Peptides Permeability Pharmaceutical Preparations Plasma Plasma Proteins Process Prodrugs Property Protease Inhibitor Protein Binding Proteins Rattus Sampling Saquinavir Simulate Site Solubility Sprague-Dawley Rats Therapeutic Therapeutic Agents Tight Junctions Treatment Protocols Viral Vitamins Water absorption analog aqueous chemical stability cytotoxicity design efflux pump improved in vivo intestinal epithelium intestinal peptide-proton cotransporter monolayer novel overexpression prevent receptor uptake valyltyrosine valylvaline

项目摘要

DESCRIPTION: Blood brain barrier (BBB) presents a significant challenge to the delivery of therapeutic agents to the brain. Tight junctions prevent free diffusion of small polar molecules across this barrier. However, entry of large lipid soluble molecules is also limited across BBB by the presence of several ABC (ATP binding cassette) efflux transporters i.e., P- glycoprotein (P-gp) and multi-drug resistance associated proteins (MRPs). Inclusion of HIV protease inhibitors (PIs) in `highly active antiretroviral therapy' (HAART) has substantially improved clinical outcomes in AIDS patients. However, a major challenge with current anti-HIV drug regimen is the inability of PIs to attain sufficient concentrations in CNS resulting in persistent viral replication and a HIV sanctuary site in the brain parenchyma. Sub-therapeutic concentration of PIs in CNS also leads to drug resistance and AIDS related dementia. One of the major factors that limit CNS permeation of PIs is the presence of efflux proteins i.e, P-gp and MRPs on brain capillary endothelial cells. Therefore the objective of this application is to develop novel prodrug strategies to circumvent ABC transporter mediated efflux and to improve brain permeation of HIV protease inhibitors. Prodrug modification of PIs is one such promising strategy where the ligand linked PIs can bypass efflux processes by becoming substrates for influx transporters such as vitamin, and amino acid transporters present on the blood brain barrier. We hypothesize that the ligand coupled PIs will permeate CNS efficiently by binding and translocating by membrane influx transporters/receptors and bypass membrane efflux pumps like P-gp and MRP. Our preliminary results clearly indicate that prodrugs designed for influx transporters can efficiently bypass efflux pumps. We also propose a novel pro-prodrug strategy where a dipeptide prodrug moiety will be designed so that it can be identified by the peptide transporter present on the intestinal epithelium. Once the dipeptide prodrug reaches systemic circulation it will be converted to amino acid prodrug which can then be identified by the amino acid transporters on the BBB. This pro-prodrug strategy will not only result in increased oral absorption of poorly absorbed PIs but also can result in higher CNS concentrations. Rat brain endothelial cells co-cultured with astrocytes will be employed as a model mimicking BBB to study permeation of the synthesized prodrugs. Finally, in-vivo rat brain microdialysis will be employed to delineate CNS pharmacokinetics of prodrugs following oral and IV administrations. Thus, overall hypothesis of this grant application is to design prodrug and pro-prodrug derivatives of PIs that may result in (a) circumvention of P-gp and MRP mediated efflux (b) higher permeability due to enhanced uptake by influx transporters, (c) higher oral bioavailability (d) lower plasma protein binding (e) higher metabolic stability against CYP 450 enzymes (f) higher aqueous solubility and (g) higher brain uptake.

描述：血脑屏障（BBB）对将治疗剂递送到大脑提出了重大挑战。紧密的连接阻止小极性分子在该屏障中的自由扩散。但是，通过存在几种ABC（ATP结合盒）外排转运蛋白，即P-糖蛋白（P-GP）和多药耐药相关蛋白（MRP），大脂质可溶性分子的进入也受到BBB的限制。在“高活性抗逆转录病毒疗法”（HAART）中纳入HIV蛋白酶抑制剂（PIS）在AIDS患者中已大大改善了临床结果。然而，当前抗HIV药物方案的主要挑战是PI无法在中枢神经系统中获得足够的浓度，从而导致持续的病毒复制和HIV避难所在脑实质中。中枢神经系统中PI的亚治疗浓度也导致耐药性和与艾滋病相关的痴呆。限制PI渗透的主要因素之一是存在外排蛋白，即脑毛细管内皮细胞上的P-gp和MRP。因此，该应用的目的是制定新型的前药策略来规避ABC转运蛋白介导的外排并改善HIV蛋白酶抑制剂的大脑渗透。 PIS的前药修饰是一种有前途的策略，配体连接的PI可以通过成为涌入转运蛋白（例如维生素）和存在于血脑屏障上的氨基酸转运蛋白的底物来绕过外排的过程。我们假设配体偶联的PI将通过膜涌入和易位的渗透转运蛋白/受体和旁路膜外排泵（如P-gp和MRP）有效地渗透CNS。我们的初步结果清楚地表明，专为涌入转运蛋白设计的前药可以有效地绕开外排泵。我们还提出了一种新型的促生策略，其中将设计二肽前药部分，以便可以通过存在于肠上皮上的肽转运蛋白来识别它。一旦二肽前药到达全身循环，它将转换为氨基酸前药，然后可以由BBB上的氨基酸转运蛋白鉴定。这种启动的策略不仅会导致吸收不良的PI的口服吸收增加，而且还会导致CNS浓度更高。与星形胶质细胞共培养的大鼠脑内皮细胞将被用作模仿BBB的模型，以研究合成前药的渗透。最后，将采用体内大鼠大脑微透析来描述口服和IV施用后的前药的CNS药代动力学。因此，该赠款应用的总体假设是设计PI的前药和促生生物衍生物，这可能导致（a）绕过P-gp和MRP介导的费用（b）由于涌入转运蛋白的摄取增强而引起的较高的渗透率（b）较高的口服生物可利用性（D）较高的质量蛋白质（D）较高的含量（d）较高的含量（D）较高的含量（d）较高的含量（d）coptip posite（d）较高的含量（d）copip posite（d）copip posite（d）copip posite（d）copip posite focip afters（d）copip posite focip afters（d）。水溶性和（g）较高的大脑吸收。