Multifunctional Nanoemulsions for Modulation of BBB Transport

描述（由申请人提供）：血脑屏障（BBB）在用于中枢神经系统（CNS）疾病的治疗药物的全身给药中提出了巨大的挑战。此外，在感染性疾病（如HIV/AIDS）中缺乏有效的治疗传递，使得病毒能够将CNS用作避难所。由于BBB既是物理的（例如，紧密的细胞连接）和生物学（例如，膜外排转运蛋白）对药物转运的障碍，解决这两个问题的多模式策略对于有效全身递送到CNS中是必要的。在这项R21提案中，主要目标是开发和评估多功能水包油纳米乳剂，专门用富含ω-3多不饱和脂肪酸（PUFA）的食用油制成，以增强BBB渗透性，并掺入姜黄素（CUR）以下调膜外排转运蛋白。使用沙奎那韦（SQV），一种模型HIV蛋白酶抑制剂，也是一种P-糖蛋白底物，我们将检查在大脑中的全身递送效率。我们的初步研究表明，含有SQV的亚麻籽油纳米乳可以促进口服吸收和血脑屏障通透性。此外，磁共振成像（MRI）研究与钆离子（Gd 3+）纳入纳米乳液也显示对比度增强。申请的具体目的是：（1）制备、表征和优化含有CUR-I的亚麻籽和鱼油纳米乳剂，其具有用于MRI和SQV的Gd 3+离子，以增强药物递送效率，（2）在BBB共培养模型中用CUR、MRI对比度增强和SQV渗透性增强对外排转运蛋白下调的体外评价，和（3）在Balb/c小鼠中全身施用CUR/SQV纳米乳剂制剂后的药物递送功效的体内评价和MRI研究。使用富含ω-3脂肪酸的油来增强渗透性和使用CUR来下调外排转运蛋白，所提出的多功能纳米乳剂系统将为具有低CNS生物利用度的疏水性治疗剂的非侵入性全身给药提供新的平台。多功能纳米乳液策略可以扩展到艾滋病毒/艾滋病治疗以外的其他传染病，癌症和神经退行性疾病。 公共卫生相关性：发现用于治疗脑疾病的超过98%的小分子治疗剂在全身施用时不能穿过血脑屏障（BBB）。此外，在艾滋病毒/艾滋病和其他感染中，尽管进行了慢性抗病毒治疗，大脑也是病毒存活的有效避难所。由于血脑屏障是药物转运的物理和生物障碍，我们的策略是开发一种可以解决这两个问题的运载工具。我们将专门用富含omega-3多不饱和脂肪酸的油配制水包油纳米乳剂，以增加BBB渗透，并使用姜黄素减少药物外排。将以抗HIV蛋白酶抑制剂沙奎那韦作为模型药物，进行评价脑内递送效率改善的研究。此外，我们将制定与钆离子的磁共振成像研究的纳米乳液。

DESCRIPTION (provided by applicant): The blood-brain barrier (BBB) presents a formidable challenge in systemic delivery of therapeutic agents intended for central nervous system (CNS) diseases. In addition, lack of effective therapeutic delivery in infectious diseases, like HIV/AIDS, allows the virus to use the CNS as a sanctuary site. Since the BBB is both a physical (e.g., tight cellular junctions) and biological (e.g., membrane efflux transporters) obstacle to drug transport, a multi-modal strategy that addresses both of these issues is necessary for effective systemic delivery into the CNS. In this R21 proposal, the main objective is to develop and evaluate multifunctional oil-in-water nanoemulsions, made specifically with omega-3 polyunsaturated fatty acids (PUFA)-rich edible oils to enhance BBB permeability, and incorporate curcumin (CUR) for down-regulation of membrane efflux transporters. Using saquinavir (SQV), a model HIV protease inhibitor, which is also a P-glycoprotein substrate, we will examine systemic delivery efficiency in the brain. Our preliminary studies show that SQV- containing flax-seed oil nanoemulsions can promote oral absorption and BBB permeability. In addition, magnetic resonance imaging (MRI) studies with gadolinium ion (Gd3+)-incorporated nanoemulsions also show contrast enhancement. The specific aims of the application are to: (1) prepare, characterize, and optimize CUR-containing flax- seed and fish oil nanoemulsions with Gd3+ ions for MRI and SQV for enhanced drug delivery efficiency, (2) in vitro evaluations of efflux transporter down-regulation with CUR, MRI contrast enhancement, and SQV permeability enhancement in BBB co-culture model, and (3) in vivo evaluations of drug delivery efficacy upon systemic administration of CUR/SQV nanoemulsion formulations and MRI studies in Balb/c mice. The proposed multifunctional nanoemulsion systems, made with the use of omega-3 fatty acids-rich oils for enhancing permeability and CUR for down-regulation of efflux transporters, will provide a novel platform for non-invasive systemic administration of hydrophobic therapeutic agents with low CNS bioavailability. The multifunctional nanoemulsion strategy can be extended beyond HIV/AIDS therapy to other infectious diseases, cancer, and neurodegenerative diseases. PUBLIC HEALTH RELEVANCE: More than 98% of small molecules therapeutics discovered for the treatment of brain diseases cannot cross the blood-brain barrier (BBB) upon systemic administration. Additionally, in HIV/AIDS and other infections, the brain also acts as an effective sanctuary site for the virus to survive despite chronic anti-viral therapy. Since the BBB is both a physical and biological obstacle to drug transport, our strategy is to develop a delivery vehicle that can address both of these issues. We will formulate oil-in-water nanoemulsions specifically with oils rich in omega-3 polyunsaturated fatty acids to increase BBB penetration and use curcumin to reduce drug efflux. Studies to evaluate improvement in delivery efficiency in the brain will be carried out with saquinavir, an anti-HIV protease inhibitor as a model drug. Additionally, we will formulate the nanoemulsion with gadolinium ions for magnetic resonance imaging studies.