Understanding interactions between brain reward and sleep systems in driving maladaptive behaviors

了解大脑奖励和睡眠系统之间的相互作用在驱动适应不良行为中的作用

基本信息

批准号：
10918950
负责人：
Andrew Kesner
金额：
$ 59.19万
依托单位：
NATIONAL INSTITUTE ON ALCOHOL ABUSE AND ALCOHOLISM
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10918950
关键词：
Abstinence Acetylcholine Action Potentials Affect Animals Appetitive Behavior Architecture Area Arousal Automobile Driving Behavior Behavioral Model Brain Brain region CNR1 gene Calcium Cannabis Cell Nucleus Chronic Clozapine Complex Consummatory Behavior Consumption Cues Darkness Data Desire for food Dopamine Drug usage Endocannabinoids Enterobacteria phage P1 Cre recombinase Exposure to Fiber Genes Genetic Recombination Glutamates Goals Homing Human Individual Injections Knock-out Learning Ligands Light Measures Medial Mediating Messenger RNA Modeling Motivation Mus Nature Neurons Neurotransmitters Nucleus Accumbens Oxides Pathway interactions Phase Photometry Presynaptic Terminals Procedures Process Property Proteins Publications REM Sleep Relapse Research Retrieval Rewards Role Site Sleep Sleep disturbances Stimulus Substance Use Disorder Sucrose System Techniques Thalamic structure Time Training Transgenic Organisms Ventral Striatum Ventral Tegmental Area Viral Withdrawal Withdrawal Symptom Work behavior influence brain circuitry cannabis cessation cannabis withdrawal cognitive enhancement designer receptors exclusively activated by designer drugs dopaminergic neuron experimental analysis flexibility gamma-Aminobutyric Acid in vivo interest maladaptive behavior marijuana use motivated behavior neural neuromechanism neurotransmitter release non rapid eye movement pre-clinical presynaptic neurons programs receptor reduce symptoms response reward circuitry sleep behavior substance misuse substance use synergism timeline vigilance

项目摘要

FY2023 was the second year of this project. We have continued following up on findings from the first publication related to this research program (See: Kesner et. al., 2022. PMID: 35478010). That publication describes our work developing pre-clinical sleep and behavioral models of cannabis withdrawal symptoms. This research suggests that brain regions that express cellular machinery related to eCB activity and are associated with both sleep and motivated behaviors may be important loci to assess the neural mechanisms governing withdrawal phenomena associated with cessation of cannabis, and potentially other misused substances. One such brain area that we feel is understudied is the medial septum (MS). The MS expresses cannabinoid receptor type 1 (CB1), which predominantly occupies presynaptic neuron terminals, and is the main target for the psychoactive properties and misuse liability of THC. Release of endocannabinoids (eCBs) from neurons in the MS would act in a retrograde manner to reduce the release of neurotransmitters from presynaptic terminals in the MS. There are several brain regions that have neurons that make CB1 and project to the MS. One region, the supramammillary nucleus (SuM), is known to be involved in sleep-wake processes, heavily expresses mRNA for CB1, and densely projects to the septal complex. We used an intersectional viral strategy to express Cre-recombinase in SuM neurons projecting to the MS in mice that have the gene encoding CB1 flanked by loxp sites. This results in a Cre-recombination-mediated deletion of CB1 on SuM neurons that project to MS. We compared sleep in these mice to wildtype littermates that received the same intracranial viral injections and found that SuM to MS CB1 knockout increases NREM sleep during the active phase of the light cycle, while decreasing REM sleep in the inactive phase. These data confirm that both eCB release and its action on CB1 receptors in the MS is important for sleep-wake processes. During the past year we have also performed similar studies targeting another brain region involved in sleep vigilance-state architecture, the ventral medial thalamus (VM). When removing CB1 from VM circuitry, we found mice were spending less time in NREM sleep during the dark phase. These results show differential contributions of CB1 to sleep depending on which sleep pathways it is acting on. Beyond its role in sleep, the MS has also been implicated in reward seeking behaviors, making it an interesting region to study in relation to synergy of sleep and reward related brain circuitry. The MS is comprised of neurons that primarily make and release the inhibitory neurotransmitter gamma-Aminobutyric acid, the excitatory neurotransmitter glutamate (GLU), or the modulatory neurotransmitter acetylcholine. Of these distinct subpopulations of neurons within the MS, the GLU neurons (MS-GLU) are particularly understudied and have recently been implicated in reward processes. We know that selective stimulation of these neurons using optogentics is reinforcing in mice, who will actively press a lever to earn stimulation specifically of MS-GLU neurons. These neurons in turn project to the ventral tegmental area (VTA), a brain region highly implicated in motivated behavior. This pathway will thus influence VTA dopaminergic neuron activity and dopamine release in the ventral striatum. Beyond these recent findings, little is known about how MS-GLU neurons respond during natural reward seeking behaviors or how modulation of their activity can influence these behaviors. Our group has performed a set of studies to elucidate the role of these neurons in these processes. We expressed either the excitatory designer receptor exclusively activated by designer drug (DREADD) hM3D-Gq, the inhibitory DREADD hM4D-Gi, or control mCherry protein exclusively on MS-GLU neurons. We trained mice to perform a basic reward seeking procedure where one lever press on an active lever (of two levers) resulted in delivery of a sucrose reward. We found that administration of the DREADD ligand, clozapine-n-oxide (CNO) resulted in reduced lever pressing in hM4D-Gi-expressing mice, but not in hM3D-Gq or control mice. Additionally, consummatory behaviors were increased in the hM4D-Gi group but not in other groups. These data suggest that taking MS-GLU neurons offline alters the appetitive and consummatory processes associated with goal directed behaviors in an opposite fashion. When we reversed the lever assignments, where the previously active lever did nothing, but pressing the other lever delivered reward, the hM3D-Gq group adapted their behavior to this new contingency much faster than the control mice, and the hM4D-Gi mice never appropriately adapted. These findings suggest augmenting MS-GLU activity plays a role in enhancing cognitive flexibility. we then used fiber photometry techniques to measure calcium activity in MS-GLU neurons. Calcium activity is a correlate of neuronal activity, so increased calcium levels indicate action potentials and general neuronal activity. In mice performing the same reward-seeking behaviors we found profoundly reduced activity in MS-GLU neurons during reward consumption. MS-GLU neuron activity also appears to encode some valence of different components of the appetitive behaviors; as activity dynamics are different depending on which lever the mouse presses and whether reward was present during consummatory behaviors. In addition, we have begun studying the interactions between MS-GLU neurons and canonical reward circuitry, specifically dopamine (DA) activity in the nucleus accumbens (NAc). We examined NAc-DA responses during 3 consecutive days while the animals performed a Pavlovian strategy switch paradigm, all while MS-GLU neurons were modulated via DREADDs. Analysis of these experiments is ongoing, but preliminary results indicate NAc-DA changes in response to the two cues in this paradigm differ depending on MS-GLU modulation via DREADDs. Of particular note, we see a far smaller NAc-DA response upon a stimulus that used to predict a reward (but now does not) in Gq mice compared to Gi or mCherry groups on Day 1 of the strategy switch paradigm. We also observe potentially larger increase in NAc-DA upon reward retrieval after a new stimulus that predicts a reward in the Gq group again on Day 1. These Day 1 observations are intriguing as they suggest increasing MS-GLU activity during the first day of a strategy switch paradigm helps the animal better disregard the old reward predictive cue, and better associate the new predictive cue with reward. In essence, increasing MS-GLU activity via Gq DREADDs seems to enhance the timeline in which reward prediction error may factor into the animal learning the new cue-reward pairing, and extinguish the old cue-reward pairing. These data are being prepared for article submission. Overall, we have begun homing in on brain circuitry that is involved in both motivation and arousal processes to assess the interaction between these processes in sleep and goal directed behavior.

2023财年是该项目的第二年。我们继续跟进与该研究计划有关的第一个出版物的发现（请参阅：Kesner等，2022。PMID：35478010）。该出版物描述了我们开发临床前睡眠和大麻戒断症状的行为模型的工作。这项研究表明，表达与欧洲央行活性相关的细胞机制并与睡眠和动机行为相关的大脑区域可能是评估有关戒断与戒烟大麻及其他滥用物质有关的戒断现象的神经机制的重要基因座。我们觉得正在研究的大脑区域是内侧隔膜（MS）。 MS表达1型大麻素受体（CB1），主要占据突触前神经元末端，并且是THC的精神活性特性和滥用责任的主要目标。 MS中神经元的内源性大麻素（ECB）释放将以逆行方式起作用，以减少MS突触前末端的神经递质的释放。有几个大脑区域的神经元可以使CB1和向MS投影。已知一个区域，即超核核（SUM），与睡眠效益过程有关，大量表达CB1的mRNA，并密集地向中间复合体投射。我们使用了一个交叉病毒策略来表达在MS的总和神经元中表达CRE-结构酶，这些神经元在小鼠的MS上表达具有编码CB1的基因，该基因编码了LOXP位点的CB1。这会导致CRE结构介导的CB1对MS的总和神经元的缺失。我们将这些小鼠的睡眠与接受相同颅内病毒注射的野生型同窝仔进行了比较，并发现在光周期的活动阶段，与MS CB1敲除的总和增加了NREM睡眠，同时减少了不活跃阶段的REM睡眠。这些数据证实，欧洲央行释放及其对MS中CB1受体的作用对于睡眠觉醒过程很重要。在过去的一年中，我们还进行了类似的研究，针对另一个参与睡眠警惕状态建筑的大脑区域，即腹侧丘脑（VM）。从VM电路中删除CB1时，我们发现在黑暗阶段，在NREM睡眠中花费的时间更少。这些结果表明，根据其作用的睡眠途径，CB1对睡眠的贡献有所不同。除了其在睡眠中的作用外，MS还与寻求奖励的行为有关，使其成为与睡眠和奖励相关的脑电路的研究的有趣区域。 MS由主要制造和释放抑制性神经递质γ-氨基丁酸，兴奋性神经递质谷氨酸（GLU）或调节性神经递质的神经递质的神经递质的神经元组成。在MS内神经元的这些独特的亚群中，GLU神经元（MS-GLU）特别研究了，最近与奖励过程有关。我们知道，选择性刺激这些神经元在小鼠中正在加强这些神经元，后者将积极按杠杆来赚取专门对MS-GLU神经元的刺激。这些神经元反过来又向腹侧对接区域（VTA）进行了项目，这是一个高度涉及动机行为的大脑区域。因此，该途径将影响腹侧纹状体中VTA多巴胺能神经元活性和多巴胺释放。除了这些最新发现之外，对MS-GLU神经元如何在自然奖励寻求行为或其活动的调制如何影响这些行为的情况下响应的知之甚少。我们的小组已经进行了一系列研究，以阐明这些神经元在这些过程中的作用。我们表达了由Designer Dress（Dreadd）HM3D-GQ，抑制性DREADD HM4D-GI（Dreadd）专门激活的兴奋性设计器受体，或者仅在MS-GLU神经元上控制MCHERRY蛋白。我们训练了小鼠执行基本的奖励寻求程序，其中一个杠杆按下（两个杠杆）的杠杆导致提供了蔗糖奖励。我们发现，施用Dreadd配体，氯氮平-N-氧化物（CNO）导致HM4D-GI表达小鼠的杠杆按压降低，但在HM3D-GQ或对照小鼠中却没有减少。此外，HM4D-GI组的完整行为增加，但在其他组中则没有增加。这些数据表明，使MS-GLU神经元离线改变了与目标定向行为相关的食欲和完整过程。当我们逆转杠杆任务时，先前活跃的杠杆什么也没做，但按下另一个杠杆获得了奖励，HM3D-GQ组将其行为适应了这种新的偶然性，而不是控制小鼠，而HM4D-GI小鼠从未适当适应过。这些发现表明，增强MS-GLU活性在增强认知灵活性中起作用。然后，我们使用纤维光度法技术来测量MS-GLU神经元中的钙活性。钙活性是神经元活性的相关性，因此钙水平提高表明作用电位和一般神经元活性。在执行相同奖励行为的小鼠中，我们发现在奖励消费期间，MS-GLU神经元的活动大大减少了。 MS-GLU神经元活性似乎也编码了食欲行为的不同组成部分的某些价。由于活动动力学不同，取决于小鼠按下的杠杆以及在完成行为期间是否存在奖励。此外，我们已经开始研究MS-GLU神经元与规范奖励电路之间的相互作用，特别是伏隔核（NAC）中的多巴胺（DA）活性。我们连续3天检查了NAC-DA的反应，而动物进行了帕夫洛维亚策略开关范式，而MS-GLU神经元则通过Dreadds调节。对这些实验的分析正在进行中，但初步结果表明，根据MS-GLU通过Dreadds的调制，NAC-DA对此范式的响应有所不同。尤其值得注意的是，与GI小鼠相比，在策略转换范式的第1天，我们看到了用于预测GQ小鼠的奖励（但现在不明）的刺激的NAC-DA响应。我们还观察到新的刺激后，我们还会观察到NAC-DA的奖励回收可能会增加，从而预测了第1天再次预测GQ组的奖励。这些第1天的观察结果令人着迷，因为它们暗示在策略开关的第一天增加MS-GLU活动的增加，可以在策略切换范式的第一天增加范围，从而帮助动物更好地忽略旧的奖励预测提示，并更好地与新的预测奖励相关联。从本质上讲，通过GQ Dreadds增加MS-GLU活动似乎增强了时间表，在这种时间表中，奖励预测误差可能会导致学习新的提示奖励配对，并熄灭旧的提示奖励配对。这些数据正在为文章提交准备。总体而言，我们已经开始在脑电路上进行归宿，这些脑电路既参与动机和唤醒过程，以评估这些过程在睡眠和目标定向行为中之间的相互作用。