ICAL: Impact of Cannabinoids Across Lifespan: Molecular Project

分子工程：综述 青少年服用Δ-9-四氢大麻酚会导致长期的神经行为损害 在小鼠和大鼠身上。分子计划将检验这样一种假设，即这些持久的影响是由 CB1型大麻素受体(CB1R)过度激活，触发表观遗传过程 在区域和电路特异性下调内源性大麻素(ECB)信号。我们有两个具体的 目标。在目标1中，我们将研究青春期急性或长期暴露于THC是否会改变 欧洲央行系统的分子组成，和/或该系统与环境接触的能力 刺激物。我们将在小鼠和大鼠身上测试急性和延长的THC方案，以模拟 青少年偶尔或每天吸食大麻。结果将在动物的三个阶段进行评估 寿命：治疗结束(最后一次注射后24小时)、成年期(出生后一天，PND 70)和中年 (PND 300)。为了确定THC影响的年龄相关性，成年动物(PND 70)将受到 到一个相同的协议。我们将确定急性或长期接触青少年THC对(I)的影响 欧洲央行复合体的脂类、蛋白质和基因成分；(Ii)表观遗传修饰；以及(Iii)刺激- 依赖于体外和体内的ECB信号。目标2将确定导致这种疾病的分子机制 诱导和维持ECB信号中持续的大麻素依赖改变。专注于 延长THC协议-我们预计这将对ECB系统、突触活动产生最强烈的影响 和行为-我们将使用功能损失和/或功能获得策略来定义CBR子类型(S) 调解青少年THC治疗的长期影响；并描述表观遗传学和生化 可能负责向欧洲央行信号持续变化过渡的机制。我们期待着 (I)CB1R，而不是CB2R，介导了青少年THC暴露的长期影响和(Ii)遗传 针对受THC影响的特定基因或组蛋白修饰的操作将纠正分子， 在THC治疗的动物中观察到突触和行为缺陷。对经久不衰的深刻理解 THC在遗传、表观遗传和生化水平上的作用将有几个应用：第一，它将指导 所有其他科学项目的研究活动：第二，它将有助于解释由 评估青少年物质使用的长期健康影响的前瞻性研究(例如，ABCD 研究)；第三，它将指导未来发现暴露结果的预测性生物标志物以及 用于合理开发旨在纠正神经行为后果的药物 青少年吸食大麻。

MOLECULAR PROJECT: SUMMARY Adolescent administration of Δ9-tetrahydrocannabinol (THC) causes long-lasting neurobehavioral impairments in mice and rats. The Molecular Project will test the hypothesis that these enduring effects result from excessive activation of CB1-type cannabinoid receptor (CB1R), which triggers epigenetic processes resulting in region- and circuit-specific down-regulation of endocannabinoid (ECB) signaling. We have two specific aims. In Aim 1, we will examine whether acute or prolonged exposure to THC during adolescence alters molecular components of the ECB system, and/or the ability of this system to be engaged by environmental stimuli. We will test, in mice and rats of both sexes, acute and prolonged THC regimens designed to mimic occasional or daily cannabis use in teenagers. Outcomes will be assessed at three stages of the animals’ lifespan: end of treatment (24 h after last THC injection), adulthood (postnatal day, PND 70) and middle age (PND 300). To determine the age-dependence of the effects of THC, adult animals (PND 70) will be subjected to an identical protocol. We will determine the effects of acute or prolonged adolescent THC exposure on (i) lipid, protein and gene constituents of the ECB complex; (ii) epigenetic modifications; and (iii) stimulus- dependent ECB signaling in vitro and in vivo. Aim 2 will identify molecular mechanisms responsible for the induction and maintenance of persistent cannabinoid-dependent alterations in ECB signaling. Focusing on the prolonged THC protocol – which we expect will have the strongest impact on ECB system, synaptic activity and behavior – we will use loss-of-function and/or gain-of-function strategies to define the CBR subtype(s) mediating the long-lasting effects of adolescent THC treatment; and describe epigenetic and biochemical mechanisms potentially responsible for the transition to persistent changes in ECB signaling. We anticipate that (i) CB1R, not CB2R, mediates the long-lasting effects of adolescent THC exposure and (ii) genetic manipulations targeting specific genes or histone modifications affected by THC will correct molecular, synaptic and behavioral deficits observed in THC-treated animals. A deep understanding of the enduring actions of THC at the genetic, epigenetic and biochemical level will have several applications: first, it will guide the research activities of all other ICAL projects: second, it will help interpret the datasets generated by prospective studies that assess the long-term health impact of adolescent substance use (e.g, the ABCD study); and, third, it will guide the future discovery of predictive biomarkers of exposure outcomes as well as for the rational development of medications aimed at correcting the neurobehavioral consequences of teenage cannabis use.