Blood Brain Barrier Changes Induced by Pain

描述(由申请人提供)：疼痛每年折磨着超过1.16亿美国人，估计花费了6350亿美元的医疗费用和生产力损失。疼痛(急性/手术后和慢性)的治疗通常涉及阿片类镇痛剂。我们发现，外周炎性疼痛(PIP)促进了BBB功能障碍，其特征是外排转运体和紧密连接(TJ)蛋白的表达和定位发生变化，以及细胞旁通透性增加(即渗漏)。这些变化的临床相关性I改变了大脑对阿片类镇痛剂的摄取。在这次更新中，我们建议测试这一新的假设，即PIP过程中的BBB功能障碍改变了阿片类止痛剂的细胞旁通透性和中枢神经系统输送，可以通过治疗靶向调节病理诱导的P-糖蛋白(Pgp)和TJ蛋白闭锁蛋白和Claudins的运输变化，这些变化对TJ寡聚蛋白组件的形成和完整性至关重要。两个具体目标将 检验这一假设。目的1：确定PIP诱导的Pgp转运改变如何导致Pgp药物外排活性增加。在这个目标中，我们将鉴定从脑微血管(目标1A)分离的PgP储存室(S)的成分。我们还将在1-72小时内将PGP阿片外流活动的变化与PGP贩运的变化相关联(一次命中或再挑战)(目标1B)。由于活性氧物种(ROS)的产生是疼痛/炎症的关键组成部分，我们将评估给予Tempol(即4-羟基-2，2，6，6-四甲基哌啶-N-氧)对PGP转运的影响，以及在1-72小时的PIP(一次点击或再激发)(目标1C)时间段内阿片类药物的脑摄取和止痛效果。目的：研究PIP诱导的TJ蛋白转运改变对细胞旁血脑屏障通透性的影响。在这个目标中，我们将确定与从脑微血管中分离的TJ相关的蛋白质(目标2A)。我们还将把细胞旁血脑屏障通透性的变化与蛋白质-蛋白质相互作用的变化联系起来，蛋白质-蛋白质相互作用的变化导致在1-72小时的PIP(一次击打或再挑战)时间段内闭塞素和克拉丁的细胞内运输的变化(目标2B)。然后，我们将评估在1-72小时的PIP(一次打击或再激发)过程中，Tempoll对occludin/claudin交易、对BBB细胞旁可待因通透性和可待因疗效的影响。(目标2C)。我们此次更新的目标是通过确定蛋白质运输在促进PIP期间BBB结构/功能改变中的作用，发现治疗疼痛和疼痛引起的BBB功能障碍的新治疗靶点。

DESCRIPTION (provided by applicant): Pain afflicts over 116 million Americans annually and costs an estimated $635 billion dollars in medical treatments and lost productivity. The treatment of pain (both acute/post-surgical and chronic) often involves opioid analgesics. We have shown that peripheral inflammatory pain (PIP) promotes BBB dysfunction characterized by changes in expression and localization of efflux transporter and tight junction (TJ) proteins as well as increased paracellular permeability (i.e., leak). The clinical relevance of these changes i altered brain uptake of opioid analgesics. In this renewal, we propose to test the novel hypothesis that BBB dysfunction during PIP, which alters paracellular permeability and CNS delivery of opioid analgesics, can be modulated by therapeutic targeting of pathology-induced changes in trafficking of P- glycoprotein (Pgp) and of TJ proteins occludin and claudins that are critical to the formation and integrity of TJ oligomeric protein assemblies. Two specific aims will test this hypothesis. Aim 1: To determine how PIP-induced changes in Pgp trafficking result in increased Pgp drug efflux activity. In this aim, we will identify components of Pgp storage compartment(s) isolated from cerebral microvessels (Aim 1A). We will also correlate changes in Pgp opioid efflux activity with changes in Pgp trafficking over a 1-72 hr time course (one-hit or rechallenge) (Aim 1B). Since production of reactive oxygen species (ROS) is a critical component of pain/inflammation, we will evaluate the effect of administration of TEMPOL (i.e., 4-hydroxy-2,2,6,6-tetramethylpiperidine-N- oxyl), a ROS scavenger, on Pgp trafficking as well as brain uptake and analgesic efficacy of opioids over a 1-72 hr time course of PIP (one-hit or rechallenge) (Aim 1C). Aim 2: To examine how PIP-induced changes in TJ protein trafficking modulate paracellular BBB permeability. In this aim, we will identify proteins associated with TJs isolated from cerebral microvessels (Aim 2A). We will also correlate changes in paracellular BBB permeability with changes in protein-protein interactions that cause changes in intracellular trafficking of occludin and claudins over a 1-72 hr time course of PIP (one-hit or rechallenge) (Aim 2B). We will then evaluate the effect of TEMPOL administration on occludin/claudin trafficking, on BBB paracellular permeability to codeine and codeine efficacy over a 1-72 hr time course of PIP (one-hit or rechallenge). (Aim 2C). Our goal in this renewal is to discover novel therapeutic targets for treating both pain and pain-induced BBB dysfunction by defining the role of protein trafficking in promoting changes in BBB structure/function that lead to altered CNS drug delivery during PIP.