In vivo calcium imaging during appetitive learning in HIV Tat transgenic mice exposed to cannabis

项目摘要 在人类免疫缺陷病毒(艾滋病毒)感染的背景下，大麻使用是一个重要的主题，是 艾滋病毒携带者(PWH)最常用的药物，尽管联合抗逆转录病毒取得了成功 治疗(购物车)。众所周知，大麻的使用可以缓解购物车上的PWH的常见症状和并发症， 包括慢性疼痛、恶心和焦虑/抑郁，但报告的结果与此相反 大麻的使用对认知能力的影响。由于CART不能越过血脑屏障，患病率较轻 到中度认知障碍，称为HIV-1相关性神经认知障碍(HAND)， 保持较高水平(50%)。大脑中特别容易感染艾滋病毒的区域包括额纹状体系统， 涉及学习、记忆和奖赏相关行为的缺陷。HIV-1感染者释放的HIV-1蛋白 细胞，包括转录反式激活因子(TAT)蛋白，已知在潜在的 手部神经病理学，包括神经元兴奋性、炎症过程和突触的持久变化 沟通。然而，尚不清楚在学习的同时，HIV TAT如何改变神经元的活动 动物正在执行一项行为任务，即在奖励的背景下。随着体内钙的建立 成像显示，投射到伏核的背内侧前额叶皮质神经元 (PFC-NAC)在成功的食欲辨别学习后增加神经元的活动。的目标是 拟议的研究是确定大麻诱导的神经性HIV小鼠模型中神经元活动的变化 行为奖赏相关学习任务及其与内源性大麻素(ECB)的关系 系统。为了实现这一目标，我们将利用一个成熟的神经艾滋病毒小鼠模型，并提出两个 目标。目的1将确定CBD：THC比率如何改变HIV TAT转基因男性和 雌性小鼠执行与奖励相关的学习任务。动物将接受病毒注射以在体内可视化 PFC-NAC神经元的钙活动和给药从行为评估开始。头部固定 小鼠将被训练执行巴甫洛夫条件反射任务，提供奖励预测线索，并进行测试 动物学习区分条件刺激预测蔗糖奖励(CS+)的能力 而不是另一个(CS-)。神经活动将在整个训练过程中被记录下来，并在训练前后进行比较 学习。目标2将确定不同的CBD：THC比例(1：15、1：1、15：1)对欧洲央行系统和 人类免疫缺陷病毒TAT转基因小鼠食欲辨别学习的病理学研究。免疫组织化学将 用于评估大麻素样受体(CB1R、CB2R、GPR55)和分解代谢的细胞特异性定位 PFC和NAC背内侧神经元、星形胶质细胞和小胶质细胞上的酶(FAAH、MAGL)；(非)ECB 配体(如AEA、2-AG、AA、OEA、PEA)将使用超高效液相色谱进行定量- 串联质谱仪。这项工作将促进对神经元活动变化的理解， 炎症，以及大麻引起的欧洲央行系统的变化都会导致艾滋病毒相关症状。

Project Summary In the context of human immunodeficiency virus (HIV) infection, cannabis use is an important topic and is the most commonly used drug among people living with HIV (PWH), despite the success of combined antiretroviral therapy (cART). Cannabis use is known to alleviate common symptoms and complications in PWH on cART, including chronic pain, nausea, and anxiety/depression, but contradicting results have been reported for cannabis use on cognitive performance. As cART does not cross the blood brain barrier the prevalence of mild to moderate forms of cognitive impairments, known as HIV-1-associated neurocognitive disorders (HAND), remain high (50%). Brain regions that are specifically vulnerable to HIV include the frontostriatal system, involving deficits in learning, memory and reward-related behaviors. HIV-1 proteins released by HIV-1 infected cells, including the transactivator of transcription (Tat) protein, are known to play a major role in the underlying HAND neuropathology, including lasting changes in neuronal excitability, inflammatory processes, and synaptic communication. Nevertheless, it is not clear how neuronal activity is altered by HIV Tat during learning while an animal is performing a behavioral task, i.e in the context of reward. With the establishment of in vivo calcium imaging, it has been shown that dorsomedial prefrontal cortex neurons that project to the nucleus accumbens (PFC-NAc) increase their neuronal activity after successful appetitive discrimination learning. The goal of the proposed study is to determine cannabis-induced changes on neuronal activity in a neuroHIV mouse model during performance of a behavioral reward-related learning task and its relation to the endocannabinoid (eCB) system. To achieve this goal, we will make use of a well-established mouse model of neuroHIV and propose two aims. Aim 1 will determine how CBD:THC ratios alter prefrontal neuronal activity in HIV Tat transgenic male and female mice performing a reward-related learning task. Animals will undergo viral injections to visualize in vivo calcium activity in PFC-NAc neurons and drug administration starts with behavioral assessment. Head-fixed mice will be trained to perform a Pavlovian conditioning task, that presents reward-predictive cues, and tests animal’s ability to learn to discriminate between a conditioned stimulus that predicts sucrose reward (CS+) but not the other (CS-). Neuronal activity will be recorded throughout training and compared before and after learning. Aim 2 will determine the effect of different CBD:THC ratios (1:15, 1:1, 15:1) on the eCB system and pathology in relation to appetitive discrimination learning in HIV Tat transgenic mice. Immunohistochemistry will be used to assess cell-specific localization of cannabinoid-like receptors (CB1R, CB2R, GPR55) and catabolic enzymes (FAAH, MAGL) on neurons, astrocytes, and microglia in the dorsomedial PFC and NAc; (non-)eCB ligands (e.g. AEA, 2-AG, AA, OEA, PEA) will be quantified using ultraperformance liquid chromatography- tandem mass spectrometry. This work will advance the understanding about how alterations in neuronal activity, inflammation, and cannabis-induced changes in the eCB system contribute to HIV-related symptoms.