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Clark PJ, Brodnik ZD, España RA. Chemogenetic Signaling in Space and Time: Considerations for Designing Neuroscience Experiments Using DREADDs. Neuroscientist 2024; 30:328-346. [PMID: 36408535 DOI: 10.1177/10738584221134587] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
The use of designer receptors exclusively activated by designer drugs (DREADDs) has led to significant advances in our understanding of the neural circuits that govern behavior. By allowing selective control over cellular activity and signaling, DREADDs have become an integral tool for defining the pathways and cellular phenotypes that regulate sleep, pain, motor activity, goal-directed behaviors, and a variety of other processes. In this review, we provide a brief overview of DREADDs and discuss notable discoveries in the neurosciences with an emphasis on circuit mechanisms. We then highlight methodological approaches to achieve pathway specific activation of DREADDs. Finally, we discuss spatial and temporal constraints of DREADDs signaling and how these features can be incorporated into experimental designs to precisely dissect circuits of interest.
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Affiliation(s)
- Philip J Clark
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Zachary D Brodnik
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Rodrigo A España
- Department of Neurobiology and Anatomy, College of Medicine, Drexel University, Philadelphia, PA, USA
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2
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Peng B, Foilb AR, Manasian Y, Li Y, Deng X, Meloni EG, Ressler KJ, Carlezon WA, Bolshakov VY. Intra-amygdala circuits of sleep disruption-induced anxiety in female mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.19.594863. [PMID: 38798391 PMCID: PMC11118584 DOI: 10.1101/2024.05.19.594863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Combining mouse genetics, electrophysiology, and behavioral training and testing, we explored how sleep disruption may affect the function of anxiety-controlling circuits, focusing on projections from the basolateral nucleus of the amygdala (BLA) to CRF-positive cells in the lateral division of the central amygdala (CeL). We found in Crh-IRES-Cre::Ai14(tdTomato) reporter female mice that 6 hours of sleep disruption during their non-active (light) cycle may be anxiogenic. Notably, the AMPAR/NMDAR EPSC amplitude ratio at the BLA inputs to CRF-CeL cells (CRF CeL ), assessed with whole-cell recordings in ex vivo experiments, was enhanced in slices from sleep-disrupted mice, whereas paired-pulse ratio (PPR) of the EPSCs induced by two closely spaced presynaptic stimuli remained unchanged. These findings indicate that sleep disruption-associated synaptic enhancements in glutamatergic projections from the BLA to CRF-CeL neurons may be postsynaptically expressed. We found also that the excitation/inhibition (E/I) ratio in the BLA to CRF CeL inputs was increased in sleep-disrupted mice, suggesting that the functional efficiency of excitation in BLA inputs to CRF CeL cells has increased following sleep disruption, thus resulting in their enhanced activation. The latter could be translated into enhanced anxiogenesis as activation of CRF cells in the CeL was shown to promote anxiety-like behaviors.
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Harada M, Capdevila LS, Wilhelm M, Burdakov D, Patriarchi T. Stimulation of VTA dopamine inputs to LH upregulates orexin neuronal activity in a DRD2-dependent manner. eLife 2024; 12:RP90158. [PMID: 38567902 PMCID: PMC10990487 DOI: 10.7554/elife.90158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024] Open
Abstract
Dopamine and orexins (hypocretins) play important roles in regulating reward-seeking behaviors. It is known that hypothalamic orexinergic neurons project to dopamine neurons in the ventral tegmental area (VTA), where they can stimulate dopaminergic neuronal activity. Although there are reciprocal connections between dopaminergic and orexinergic systems, whether and how dopamine regulates the activity of orexin neurons is currently not known. Here we implemented an opto-Pavlovian task in which mice learn to associate a sensory cue with optogenetic dopamine neuron stimulation to investigate the relationship between dopamine release and orexin neuron activity in the lateral hypothalamus (LH). We found that dopamine release can be evoked in LH upon optogenetic stimulation of VTA dopamine neurons and is also naturally evoked by cue presentation after opto-Pavlovian learning. Furthermore, orexin neuron activity could also be upregulated by local stimulation of dopaminergic terminals in the LH in a way that is partially dependent on dopamine D2 receptors (DRD2). Our results reveal previously unknown orexinergic coding of reward expectation and unveil an orexin-regulatory axis mediated by local dopamine inputs in the LH.
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Affiliation(s)
- Masaya Harada
- Institute of Pharmacology and Toxicology, University of ZürichZürichSwitzerland
| | | | - Maria Wilhelm
- Institute of Pharmacology and Toxicology, University of ZürichZürichSwitzerland
| | - Denis Burdakov
- Neuroscience Center Zürich, University and ETH ZürichZürichSwitzerland
- Department of Health Sciences and Technology, ETH ZürichZürichSwitzerland
| | - Tommaso Patriarchi
- Institute of Pharmacology and Toxicology, University of ZürichZürichSwitzerland
- Neuroscience Center Zürich, University and ETH ZürichZürichSwitzerland
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4
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Hou G, Hao M, Duan J, Han MH. The Formation and Function of the VTA Dopamine System. Int J Mol Sci 2024; 25:3875. [PMID: 38612683 PMCID: PMC11011984 DOI: 10.3390/ijms25073875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 04/14/2024] Open
Abstract
The midbrain dopamine system is a sophisticated hub that integrates diverse inputs to control multiple physiological functions, including locomotion, motivation, cognition, reward, as well as maternal and reproductive behaviors. Dopamine is a neurotransmitter that binds to G-protein-coupled receptors. Dopamine also works together with other neurotransmitters and various neuropeptides to maintain the balance of synaptic functions. The dysfunction of the dopamine system leads to several conditions, including Parkinson's disease, Huntington's disease, major depression, schizophrenia, and drug addiction. The ventral tegmental area (VTA) has been identified as an important relay nucleus that modulates homeostatic plasticity in the midbrain dopamine system. Due to the complexity of synaptic transmissions and input-output connections in the VTA, the structure and function of this crucial brain region are still not fully understood. In this review article, we mainly focus on the cell types, neurotransmitters, neuropeptides, ion channels, receptors, and neural circuits of the VTA dopamine system, with the hope of obtaining new insight into the formation and function of this vital brain region.
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Affiliation(s)
- Guoqiang Hou
- Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China (M.H.); (J.D.)
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Mei Hao
- Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China (M.H.); (J.D.)
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Jiawen Duan
- Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China (M.H.); (J.D.)
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Ming-Hu Han
- Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China (M.H.); (J.D.)
- Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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5
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Coppola G, Abagnale C, Sebastianelli G, Goadsby PJ. Pathophysiology of cluster headache: From the trigeminovascular system to the cerebral networks. Cephalalgia 2024; 44:3331024231209317. [PMID: 38415635 DOI: 10.1177/03331024231209317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
BACKGROUND Despite advances in neuroimaging and electrophysiology, cluster headache's pathogenesis remains unclear. This review will examine clinical neurophysiology studies, including electrophysiological and functional neuroimaging, to determine if they might help us construct a neurophysiological model of cluster headache. RESULTS Clinical, biochemical, and electrophysiological research have implicated the trigeminal-parasympathetic system in cluster headache pain generation, although the order in which these two systems are activated, which may be somewhat independent, is unknown. Electrophysiology and neuroimaging have found one or more central factors that may cause seasonal and circadian attacks. The well-known posterior hypothalamus, with its primary circadian pacemaker suprachiasmatic nucleus, the brainstem monoaminergic systems, the midbrain, with an emphasis on the dopaminergic system, especially when cluster headache is chronic, and the descending pain control systems appear to be involved. Functional connection investigations have verified electrophysiological evidence of functional changes in distant brain regions connecting to wide cerebral networks other than pain. CONCLUSION We propose that under the impact of external time, an inherited misalignment between the primary circadian pacemaker suprachiasmatic nucleus and other secondary extra- suprachiasmatic nucleus clocks may promote disturbance of the body's internal physiological clock, lowering the threshold for bout recurrence.
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Affiliation(s)
- Gianluca Coppola
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome Polo Pontino ICOT, Latina, Italy
| | - Chiara Abagnale
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome Polo Pontino ICOT, Latina, Italy
| | - Gabriele Sebastianelli
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome Polo Pontino ICOT, Latina, Italy
| | - Peter J Goadsby
- NIHR King's Clinical Research Facility, and Wolfson Sensory, Pain and Regeneration Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London UK
- Department of Neurology, University of California, Los Angeles, Los Angeles, California, USA
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Zamanirad F, Eskandari K, Mousavi Z, Haghparast A. Blockade of the orexin-2 receptors within the ventral tegmental area facilitates the extinction and prevents the reinstatement of methamphetamine-seeking behavior. Physiol Behav 2024; 273:114382. [PMID: 37866644 DOI: 10.1016/j.physbeh.2023.114382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 10/19/2023] [Accepted: 10/19/2023] [Indexed: 10/24/2023]
Abstract
Repeated use of methamphetamine (METH) causes severe effects on the central nervous system, associated with an increased relapse rate. The orexinergic system is highly implicated in the reward circuitry and may be a promising target for treating psychostimulant dependency. The present study aimed to investigate the involvement of the orexin system, mainly the orexin-2 receptors (OX2R) in the ventral tegmental area (VTA) in the extinction and reinstatement of METH-seeking behavior using a conditioned place preference (CPP) paradigm. To this end, animals received METH (1 mg/kg; sc) for a 5-day conditioning period. Then, in the first set of experiments, different groups of rats were given intra-VTA TCS OX2 29 (1, 3, 10, or 30 nmol/0.3 μl DMSO) as an OX2R antagonist over a 10-day extinction period. In another experiment, after the extinction period, a different set of animals received a single dose of TCS OX2 29 (1, 3, 10, or 30 nmol) before the priming dose of METH (0.25 mg/kg; sc) on the reinstatement day. The results revealed that TCS OX2 29 (10 and 30 nmol) remarkably facilitated the extinction of rewarding properties of METH (P < 0.001 for both doses). Furthermore, TCS OX2 29 (3, 10, or 30 nmol) significantly suppressed the METH-induced reinstatement (3 nmol; P < 0.05, 10 nmol; P < 0.01, and 30 nmol; P < 0.001). In conclusion, the current study revealed that the orexinergic system, specifically the VTA OX2R, is involved in METH-seeking behaviors and that manipulation of this system can be considered a potential therapeutics in treating METH dependency.
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Affiliation(s)
- Ferdos Zamanirad
- Pharmacology and Toxicology Department, Faculty of Pharmacy and Pharmaceutical Sciences, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Kiarash Eskandari
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Zahra Mousavi
- Pharmacology and Toxicology Department, Faculty of Pharmacy and Pharmaceutical Sciences, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; School of Cognitive Sciences, Institute for Research in Fundamental Sciences, Tehran, Iran; Department of Basic Sciences, Iranian Academy of Medical Sciences, Tehran, Iran.
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7
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Bouâouda H, Jha PK. Orexin and MCH neurons: regulators of sleep and metabolism. Front Neurosci 2023; 17:1230428. [PMID: 37674517 PMCID: PMC10478345 DOI: 10.3389/fnins.2023.1230428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 08/07/2023] [Indexed: 09/08/2023] Open
Abstract
Sleep-wake and fasting-feeding are tightly coupled behavioral states that require coordination between several brain regions. The mammalian lateral hypothalamus (LH) is a functionally and anatomically complex brain region harboring heterogeneous cell populations that regulate sleep, feeding, and energy metabolism. Significant attempts were made to understand the cellular and circuit bases of LH actions. Rapid advancements in genetic and electrophysiological manipulation help to understand the role of discrete LH cell populations. The opposing action of LH orexin/hypocretin and melanin-concentrating hormone (MCH) neurons on metabolic sensing and sleep-wake regulation make them the candidate to explore in detail. This review surveys the molecular, genetic, and neuronal components of orexin and MCH signaling in the regulation of sleep and metabolism.
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Affiliation(s)
- Hanan Bouâouda
- Pharmacology Institute, Medical Faculty Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Pawan Kumar Jha
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Pirino BE, Kelley AM, Karkhanis AN, Barson JR. A critical review of effects on ethanol intake of the dynorphin/kappa opioid receptor system in the extended amygdala: From inhibition to stimulation. ALCOHOL, CLINICAL & EXPERIMENTAL RESEARCH 2023; 47:1027-1038. [PMID: 37042026 PMCID: PMC10289127 DOI: 10.1111/acer.15078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/03/2023] [Accepted: 04/06/2023] [Indexed: 04/13/2023]
Abstract
The dynorphin (DYN)/kappa opioid receptor (KOR) system has increasingly been investigated as a possible pharmacotherapeutic target for alcohol use disorder, but findings on the direction of its effects have been mixed. Activation of KORs by DYN has been shown to elicit dysphoric effects, and the DYN/KOR system has canonically been considered particularly important in driving alcohol intake through negative reinforcement in dependent states. However, this review also highlights its activity in opposing the positive reinforcement that drives alcohol intake at earlier stages. Both DYN and KORs are concentrated in the extended amygdala, a set of interconnected regions that includes the bed nucleus of the stria terminalis, central nucleus of the amygdala, and nucleus accumbens shell. This review focuses on the role of the DYN/KOR system in the extended amygdala in ethanol use. It begins by examining the effects of ethanol on the expression of DYN/KOR in the extended amygdala, expression of DYN/KOR in alcohol-preferring and alcohol-avoiding animals, and the effects of knocking out DYN/KOR genes on ethanol intake. Then, it examines the effects on ethanol use in both dependent and nondependent states from systemic pharmacological manipulations of DYN/KOR and from specific manipulation of this system in regions of the extended amygdala. We propose that greater expression and binding of DYN/KOR, by reducing the positive reinforcement that drives early stages of intake, initially acts to prevent the escalation of ethanol drinking. However, prolonged, binge-like, or intermittent ethanol intake enhances levels of DYN/KOR in the extended amygdala such that the system ultimately facilitates the negative reinforcement that drives later stages of ethanol drinking. This review highlights the potential of the DYN/KOR system as a target that can affect different outcomes across different stages of ethanol drinking and the development of alcohol use disorder.
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Affiliation(s)
- Breanne E. Pirino
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, P.A. 19129
| | - Abigail M. Kelley
- Department of Psychology, Binghamton University – SUNY, Binghamton, N.Y. 13902
| | | | - Jessica R. Barson
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Philadelphia, P.A. 19129
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Mazzeo F, Meccariello R, Guatteo E. Molecular and Epigenetic Aspects of Opioid Receptors in Drug Addiction and Pain Management in Sport. Int J Mol Sci 2023; 24:ijms24097831. [PMID: 37175536 PMCID: PMC10178540 DOI: 10.3390/ijms24097831] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/14/2023] [Accepted: 04/21/2023] [Indexed: 05/15/2023] Open
Abstract
Opioids are substances derived from opium (natural opioids). In its raw state, opium is a gummy latex extracted from Papaver somniferum. The use of opioids and their negative health consequences among people who use drugs have been studied. Today, opioids are still the most commonly used and effective analgesic treatments for severe pain, but their use and abuse causes detrimental side effects for health, including addiction, thus impacting the user's quality of life and causing overdose. The mesocorticolimbic dopaminergic circuitry represents the brain circuit mediating both natural rewards and the rewarding aspects of nearly all drugs of abuse, including opioids. Hence, understanding how opioids affect the function of dopaminergic circuitry may be useful for better knowledge of the process and to develop effective therapeutic strategies in addiction. The aim of this review was to summarize the main features of opioids and opioid receptors and focus on the molecular and upcoming epigenetic mechanisms leading to opioid addiction. Since synthetic opioids can be effective for pain management, their ability to induce addiction in athletes, with the risk of incurring doping, is also discussed.
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Affiliation(s)
- Filomena Mazzeo
- Department of Economics, Law, Cybersecurity and Sports Sciences, University of Naples "Parthenope", 80133 Naples, Italy
- Department of Movement Sciences and Wellbeing, University of Naples "Parthenope", 80133 Naples, Italy
| | - Rosaria Meccariello
- Department of Movement Sciences and Wellbeing, University of Naples "Parthenope", 80133 Naples, Italy
| | - Ezia Guatteo
- Department of Movement Sciences and Wellbeing, University of Naples "Parthenope", 80133 Naples, Italy
- IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, 00143 Rome, Italy
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10
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α-Synuclein Induced the Occurrence of RBD via Interaction with OX1R and Modulated Its Degradation. Neuromolecular Med 2023:10.1007/s12017-023-08735-4. [PMID: 36689149 DOI: 10.1007/s12017-023-08735-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 01/12/2023] [Indexed: 01/24/2023]
Abstract
Rapid eye movement (REM) sleep behavior disorder (RBD) is a powerful early sign of Parkinson's disease (PD), but the pathogenetic mechanism involved in RBD remains largely unexplored. α-Synuclein has been verified to form Lewy bodies in the orexin neurons, whose activity and function rely on the orexin 1 receptor (OX1R). Dysfunction of the OX1R may induce the occurrence of RBD. Here, we determined the role of the interaction between α-Synuclein and OX1R in the pathogenesis of RBD, in vitro and in vivo. We found that injection of α-Synuclein into the lateral hypothalamus area (LHA) damaged orexin neurons and induced the RBD-like sleep pattern, to further damage dopaminergic neurons and result in locomotor dysfunction in mice. α-Synuclein interacted with OX1R, promoting the degradation of OX1R through proteasomal and lysosomal pathways. In addition, overexpression of α-Synuclein downregulated OX1R-mediated signaling, subsequently leading to orexin neuron damage. We conclude that α-Synuclein induced the occurrence of RBD via interaction with OX1R and modulated its degradation. These findings provide evidence for a novel mechanism by which the association of α-Synuclein with OX1R was attributed to α-Synuclein-induced orexin neuron damage, which may be a new molecular target for an effective therapeutic strategy for RBD pathology.
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11
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Tyree SM, Jennings KJ, Gonzalez OC, Li SB, Nicholson JR, von Heimendahl M, de Lecea L. Optogenetic and pharmacological interventions link hypocretin neurons to impulsivity in mice. Commun Biol 2023; 6:74. [PMID: 36658362 PMCID: PMC9852239 DOI: 10.1038/s42003-023-04409-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 01/03/2023] [Indexed: 01/20/2023] Open
Abstract
Neurons in the lateral hypothalamus expressing the neuropeptide Hypocretin, also known as orexin, are known critical modulators of arousal stability. However, their role in the different components of the arousal construct such as attention and decision making is poorly understood. Here we study Hypocretin neuronal circuit dynamics during stop action impulsivity in a Go/NoGo task in mice. We show that Hypocretin neuronal activity correlates with anticipation of reward. We then assessed the causal role of Hypocretin neuronal activity using optogenetics in a Go/NoGo task. We show that stimulation of Hypocretin neurons during the cue period dramatically increases the number of premature responses. These effects are mimicked by amphetamine, reduced by atomoxetine, a norepinephrine uptake inhibitor, and blocked by a Hypocretin receptor 1 selective antagonist. We conclude that Hypocretin neurons have a key role in the integration of salient stimuli during wakefulness to produce appropriate and timely responses to rewarding and aversive cues.
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Affiliation(s)
- Susan M. Tyree
- grid.168010.e0000000419368956Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Stanford, CA USA ,Present Address: Atlantia Clinical Trials, Cork, Ireland
| | - Kimberly J. Jennings
- grid.168010.e0000000419368956Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Stanford, CA USA ,grid.55460.320000000121548364Present Address: University of Texas, Austin, TX USA
| | - Oscar C. Gonzalez
- grid.168010.e0000000419368956Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Stanford, CA USA
| | - Shi-bin Li
- grid.168010.e0000000419368956Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Stanford, CA USA
| | - Janet R. Nicholson
- grid.420061.10000 0001 2171 7500Boehringer Ingelheim Pharma GmbH & Co.KG, Biberach, Germany
| | - Moritz von Heimendahl
- grid.420061.10000 0001 2171 7500Boehringer Ingelheim Pharma GmbH & Co.KG, Biberach, Germany
| | - Luis de Lecea
- grid.168010.e0000000419368956Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Stanford, CA USA
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12
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James MH, Aston-Jones G. Orexin Reserve: A Mechanistic Framework for the Role of Orexins (Hypocretins) in Addiction. Biol Psychiatry 2022; 92:836-844. [PMID: 36328706 PMCID: PMC10184826 DOI: 10.1016/j.biopsych.2022.06.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 06/07/2022] [Accepted: 06/23/2022] [Indexed: 11/22/2022]
Abstract
In 2014, we proposed that orexin signaling transformed motivationally relevant states into adaptive behavior directed toward exploiting an opportunity or managing a threat, a process we referred to as motivational activation. Advancements in animal models since then have permitted higher-resolution measurements of motivational states; in particular, the behavioral economics approach for studying drug demand characterizes conditions that lead to the enhanced motivation that underlies addiction. This motivational plasticity is paralleled by persistently increased orexin expression in a topographically specific manner-a finding confirmed across species, including in humans. Normalization of orexin levels also reduces drug motivation in addiction models. These new advancements lead us to update our proposed framework for the orexin function. We now propose that the capacity of orexin neurons to exhibit dynamic shifts in peptide production contributes to their role in adaptive motivational regulation and that this is achieved via a pool of reserve orexin neurons. This reserve is normally bidirectionally recruited to permit motivational plasticity that promotes flexible, adaptive behavior. In pathological states such as addiction, however, we propose that the orexin system loses capacity to adaptively adjust peptide production, resulting in focused hypermotivation for drug, driven by aberrantly and persistently high expression in the orexin reserve pool. This mechanistic framework has implications for the understanding and treatment of several psychiatric disorders beyond addiction, particularly those characterized by motivational dysfunction.
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Affiliation(s)
- Morgan H James
- Brain Health Institute, Rutgers University and Rutgers Biomedical and Health Sciences, Piscataway, New Jersey; Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University and Rutgers Biomedical and Health Sciences, Piscataway, New Jersey.
| | - Gary Aston-Jones
- Brain Health Institute, Rutgers University and Rutgers Biomedical and Health Sciences, Piscataway, New Jersey; Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University and Rutgers Biomedical and Health Sciences, Piscataway, New Jersey.
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13
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Linders LE, Patrikiou L, Soiza-Reilly M, Schut EHS, van Schaffelaar BF, Böger L, Wolterink-Donselaar IG, Luijendijk MCM, Adan RAH, Meye FJ. Stress-driven potentiation of lateral hypothalamic synapses onto ventral tegmental area dopamine neurons causes increased consumption of palatable food. Nat Commun 2022; 13:6898. [PMID: 36371405 PMCID: PMC9653441 DOI: 10.1038/s41467-022-34625-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 11/01/2022] [Indexed: 11/13/2022] Open
Abstract
Stress can cause overconsumption of palatable high caloric food. Despite the important role of stress eating in obesity and (binge) eating disorders, its underlying neural mechanisms remain unclear. Here we demonstrate in mice that stress alters lateral hypothalamic area (LHA) control over the ventral tegmental area (VTA), thereby promoting overconsumption of palatable food. Specifically, we show that glutamatergic LHA neurons projecting to the VTA are activated by social stress, after which their synapses onto dopamine neurons are potentiated via AMPA receptor subunit alterations. We find that stress-driven strengthening of these specific synapses increases LHA control over dopamine output in key target areas like the prefrontal cortex. Finally, we demonstrate that while inducing LHA-VTA glutamatergic potentiation increases palatable fat intake, reducing stress-driven potentiation of this connection prevents such stress eating. Overall, this study provides insights in the neural circuit adaptations caused by stress that drive overconsumption of palatable food.
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Affiliation(s)
- Louisa E. Linders
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Lefkothea Patrikiou
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Mariano Soiza-Reilly
- grid.7345.50000 0001 0056 1981Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), CONICET, University of Buenos Aires, Buenos Aires, Argentina
| | - Evelien H. S. Schut
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Bram F. van Schaffelaar
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Leonard Böger
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Inge G. Wolterink-Donselaar
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Mieneke C. M. Luijendijk
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Roger A. H. Adan
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Frank J. Meye
- grid.5477.10000000120346234Department of Translational Neuroscience, Brain Center, UMC Utrecht, Utrecht University, Utrecht, The Netherlands
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14
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Limoges A, Yarur HE, Tejeda HA. Dynorphin/kappa opioid receptor system regulation on amygdaloid circuitry: Implications for neuropsychiatric disorders. Front Syst Neurosci 2022; 16:963691. [PMID: 36276608 PMCID: PMC9579273 DOI: 10.3389/fnsys.2022.963691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/18/2022] [Indexed: 11/13/2022] Open
Abstract
Amygdaloid circuits are involved in a variety of emotional and motivation-related behaviors and are impacted by stress. The amygdala expresses several neuromodulatory systems, including opioid peptides and their receptors. The Dynorphin (Dyn)/kappa opioid receptor (KOR) system has been implicated in the processing of emotional and stress-related information and is expressed in brain areas involved in stress and motivation. Dysregulation of the Dyn/KOR system has also been implicated in various neuropsychiatric disorders. However, there is limited information about the role of the Dyn/KOR system in regulating amygdala circuitry. Here, we review the literature on the (1) basic anatomy of the amygdala, (2) functional regulation of synaptic transmission by the Dyn/KOR system, (3) anatomical architecture and function of the Dyn/KOR system in the amygdala, (4) regulation of amygdala-dependent behaviors by the Dyn/KOR system, and (5) future directions for the field. Future work investigating how the Dyn/KOR system shapes a wide range of amygdala-related behaviors will be required to increase our understanding of underlying circuitry modulation by the Dyn/KOR system. We anticipate that continued focus on the amygdala Dyn/KOR system will also elucidate novel ways to target the Dyn/KOR system to treat neuropsychiatric disorders.
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Affiliation(s)
- Aaron Limoges
- Unit on Neuromodulation and Synaptic Integration, Bethesda, MD, United States
- NIH-Columbia University Individual Graduate Partnership Program, National Institutes of Health, Bethesda, MD, United States
- Department of Biological Sciences, Columbia University, New York, NY, United States
| | - Hector E. Yarur
- Unit on Neuromodulation and Synaptic Integration, Bethesda, MD, United States
| | - Hugo A. Tejeda
- Unit on Neuromodulation and Synaptic Integration, Bethesda, MD, United States
- *Correspondence: Hugo A. Tejeda,
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15
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Lowes DC, Harris AZ. Stressed and wired: The effects of stress on the VTA circuits underlying motivated behavior. CURRENT OPINION IN ENDOCRINE AND METABOLIC RESEARCH 2022; 26:100388. [PMID: 36406203 PMCID: PMC9674332 DOI: 10.1016/j.coemr.2022.100388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Stress affects many brain regions, including the ventral tegmental area (VTA), which is critically involved in reward processing. Excessive stress can reduce reward-seeking behaviors but also exacerbate substance use disorders, two seemingly contradictory outcomes. Recent research has revealed that the VTA is a heterogenous structure with diverse populations of efferents and afferents serving different functions. Stress has correspondingly diverse effects on VTA neuron activity, tending to decrease lateral VTA dopamine (DA) neuron activity, while increasing medial VTA DA and GABA neuron activity. Here we review the differential effects of stress on the activity of these distinct VTA neuron populations and how they contribute to decreases in reward-seeking behavior or increases in drug self-administration.
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Affiliation(s)
- Daniel C. Lowes
- Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA
| | - Alexander Z. Harris
- Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA,Division of Systems Neuroscience, New York State Psychiatric Institute, New York, NY 10032, USA
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16
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You WR, Lin LC, Lin WC, Tsai MC. Differences in orexin-A level in the functional brain network of HUD patients undergoing harm reduction therapy. Medicine (Baltimore) 2022; 101:e30093. [PMID: 35984180 PMCID: PMC9387983 DOI: 10.1097/md.0000000000030093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Orexins regulate the reward-seeking pathway and also play a role in drug addiction. The aim of this study was an investigation of the changes in serum level of orexin-A as well as changes in the functional brain network in heroin use disorder (HUD) patients undergoing harm reduction therapy (HRT). Twenty-five HUD patients undergoing HRT that included methadone and buprenorphine, and 31 healthy control (HC) subjects, were enrolled for this study. Serum orexin-A levels and brain-derived neurotrophic factor were measured with assay kits. The functional brain network in HUD patients and HC was investigated and assessed using seed-based analysis and functional brain MRI scans. t Tested orexin-A levels were found to be significantly higher in HUD patients undergoing HRT than in HCs (P < .05). Analysis showed the functional activity of the right ventral anterior insula (RVAI) in HUD patients to be significantly lower than in HCs (P < .05, Family-Wise Error) corrected). In addition, the internetwork functional connectivity was significantly lower in the left nucleus accumbens and left dorsal anterior insula in the HUD subjects than in HCs (P < .05, Family-Wise Error corrected). In this study, no significant correlation between orexin-A levels and functional brain networks was found. However, the results suggest that HRT might increase orexin-A levels and decrease functional activity in RVAI in HUD patients.
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Affiliation(s)
- Wan-Ru You
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Liang-Chun Lin
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan
| | - Wei-Che Lin
- Department of Diagnostic Radiology, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Meng-Chang Tsai
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, Taiwan
- *Correspondence: Meng-Chang Tsai, Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Kaohsiung, 123 Ta-Pei Road, Niao-Sung, Kaohsiung 83305, Taiwan (e-mail: )
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17
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Dunigan AI, Roseberry AG. Actions of feeding-related peptides on the mesolimbic dopamine system in regulation of natural and drug rewards. ADDICTION NEUROSCIENCE 2022; 2:100011. [PMID: 37220637 PMCID: PMC10201992 DOI: 10.1016/j.addicn.2022.100011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The mesolimbic dopamine system is the primary neural circuit mediating motivation, reinforcement, and reward-related behavior. The activity of this system and multiple behaviors controlled by it are affected by changes in feeding and body weight, such as fasting, food restriction, or the development of obesity. Multiple different peptides and hormones that have been implicated in the control of feeding and body weight interact with the mesolimbic dopamine system to regulate many different dopamine-dependent, reward-related behaviors. In this review, we summarize the effects of a selected set of feeding-related peptides and hormones acting within the ventral tegmental area and nucleus accumbens to alter feeding, as well as food, drug, and social reward.
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Affiliation(s)
- Anna I. Dunigan
- Department of Biology and Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Aaron G. Roseberry
- Department of Biology and Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
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18
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Abraham AD, Casello SM, Land BB, Chavkin C. Optogenetic stimulation of dynorphinergic neurons within the dorsal raphe activate kappa opioid receptors in the ventral tegmental area and ablation of dorsal raphe prodynorphin or kappa receptors in dopamine neurons blocks stress potentiation of cocaine reward. ADDICTION NEUROSCIENCE 2022; 1. [PMID: 36176476 PMCID: PMC9518814 DOI: 10.1016/j.addicn.2022.100005] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Behavioral stress exposure increases the risk of drug-taking in individuals with substance use disorders by mechanisms involving the dynorphins, which are the endogenous neuropeptides for the kappa opioid receptor (KOR). KOR agonists have been shown to encode dysphoria, aversion, and changes in reward valuation, and kappa opioid antagonists are in clinical development for treating substance use disorders. In this study, we confirmed that KORs were expressed in dopaminergic neurons in the ventral tegmental area (VTA) of male C57BL6/J mice. Genetic ablation of KORs from dopamine neurons blocked the potentiating effects of repeated forced swim stress on cocaine conditioned place preference (CPP). KOR activation inhibited dopamine neuron GCaMP6m calcium activity in VTA during swim stress and caused a rebound enhancement during the period after stress exposure. Transient optogenetic inhibition of VTA dopamine neurons with AAV5-DIO-SwiChR was acutely aversive in a real time place preference assay and blunted cocaine CPP when inhibition was administered concurrently with cocaine conditioning. However, when inhibition preceded cocaine conditioning by 30 min, cocaine CPP was enhanced. Retrograde tracing with CAV2-DIO-ZsGreen identified a population of prodynorphinCre neurons in the dorsal raphe nucleus (DRN) projecting to the VTA. Optogenetic stimulation of dynorphinergic neurons within the DRN by Channelrhodopsin2 activated KOR in VTA and ablation of prodynorphin blocked stress potentiation of cocaine CPP. Together, these studies demonstrate the presence of a dynorphin/KOR midbrain circuit that projects from the DRN to VTA and is involved in altering the dynamic response of dopamine neuron activity to enhance drug reward learning.
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19
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Duffet L, Kosar S, Panniello M, Viberti B, Bracey E, Zych AD, Radoux-Mergault A, Zhou X, Dernic J, Ravotto L, Tsai YC, Figueiredo M, Tyagarajan SK, Weber B, Stoeber M, Gogolla N, Schmidt MH, Adamantidis AR, Fellin T, Burdakov D, Patriarchi T. A genetically encoded sensor for in vivo imaging of orexin neuropeptides. Nat Methods 2022; 19:231-241. [PMID: 35145320 PMCID: PMC8831244 DOI: 10.1038/s41592-021-01390-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 12/16/2021] [Indexed: 02/07/2023]
Abstract
Orexins (also called hypocretins) are hypothalamic neuropeptides that carry out essential functions in the central nervous system; however, little is known about their release and range of action in vivo owing to the limited resolution of current detection technologies. Here we developed a genetically encoded orexin sensor (OxLight1) based on the engineering of circularly permutated green fluorescent protein into the human type-2 orexin receptor. In mice OxLight1 detects optogenetically evoked release of endogenous orexins in vivo with high sensitivity. Photometry recordings of OxLight1 in mice show rapid orexin release associated with spontaneous running behavior, acute stress and sleep-to-wake transitions in different brain areas. Moreover, two-photon imaging of OxLight1 reveals orexin release in layer 2/3 of the mouse somatosensory cortex during emergence from anesthesia. Thus, OxLight1 enables sensitive and direct optical detection of orexin neuropeptides with high spatiotemporal resolution in living animals.
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Affiliation(s)
- Loïc Duffet
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Seher Kosar
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Mariangela Panniello
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, Genova, Italy
| | - Bianca Viberti
- Center for Experimental Neurology (ZEN), Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Edward Bracey
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Anna D Zych
- Circuits for Emotion Research Group, Max Planck Institute of Neurobiology, Martinsried, Germany
- International Max Planck Research School for Translational Psychiatry (IMPRS-TP), Munich, Germany
| | | | - Xuehan Zhou
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Jan Dernic
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Luca Ravotto
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Yuan-Chen Tsai
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Marta Figueiredo
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Shiva K Tyagarajan
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, Genova, Italy
| | - Bruno Weber
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, Genova, Italy
| | - Miriam Stoeber
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Nadine Gogolla
- Circuits for Emotion Research Group, Max Planck Institute of Neurobiology, Martinsried, Germany
| | - Markus H Schmidt
- Center for Experimental Neurology (ZEN), Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Antoine R Adamantidis
- Center for Experimental Neurology (ZEN), Department of Neurology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Tommaso Fellin
- Optical Approaches to Brain Function Laboratory, Istituto Italiano di Tecnologia, Genova, Italy
| | - Denis Burdakov
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland
| | - Tommaso Patriarchi
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland.
- Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland.
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20
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Thomas CS, Mohammadkhani A, Rana M, Qiao M, Baimel C, Borgland SL. Optogenetic stimulation of lateral hypothalamic orexin/dynorphin inputs in the ventral tegmental area potentiates mesolimbic dopamine neurotransmission and promotes reward-seeking behaviours. Neuropsychopharmacology 2022; 47:728-740. [PMID: 34663867 PMCID: PMC8782948 DOI: 10.1038/s41386-021-01196-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 09/15/2021] [Accepted: 09/20/2021] [Indexed: 01/30/2023]
Abstract
Reward and reinforcement processes are critical for survival and propagation of genes. While numerous brain systems underlie these processes, a cardinal role is ascribed to mesolimbic dopamine. However, ventral tegmental area (VTA) dopamine neurons receive complex innervation and various neuromodulatory factors, including input from lateral hypothalamic (LH) orexin/hypocretin neurons which also express and co-release the neuropeptide, dynorphin. Dynorphin in the VTA induces aversive conditioning through the Kappa opioid receptor (KOR) and decreases dopamine when administered intra-VTA. Exogenous application of orexin or orexin 1 receptor (oxR1) antagonists in the VTA bidirectionally modulates dopamine-driven motivation and reward-seeking behaviours, including the attribution of motivational value to primary rewards and associated conditioned stimuli. However, the effect of endogenous stimulation of LH orexin/dynorphin-containing projections to the VTA and the potential contribution of co-released dynorphin on mesolimbic dopamine and reward related processes remains uncharacterised. We combined optogenetic, electrochemical, and behavioural approaches to examine this. We found that optical stimulation of LH orexin/dynorphin inputs in the VTA potentiates mesolimbic dopamine neurotransmission in the nucleus accumbens (NAc) core, produces real time and conditioned place preference, and increases the food cue-directed orientation in a Pavlovian conditioning procedure. LH orexin/dynorphin potentiation of NAc dopamine release and real time place preference was blocked by an oxR1, but not KOR antagonist. Thus, rewarding effects associated with optical stimulation of LH orexin/dynorphin inputs in the VTA are predominantly driven by orexin rather than dynorphin.
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Affiliation(s)
- Catherine S. Thomas
- grid.22072.350000 0004 1936 7697Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1 Canada
| | - Aida Mohammadkhani
- grid.22072.350000 0004 1936 7697Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1 Canada
| | - Madiha Rana
- grid.22072.350000 0004 1936 7697Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1 Canada
| | - Min Qiao
- grid.22072.350000 0004 1936 7697Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1 Canada
| | - Corey Baimel
- grid.22072.350000 0004 1936 7697Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1 Canada
| | - Stephanie L. Borgland
- grid.22072.350000 0004 1936 7697Department of Physiology and Pharmacology, Hotchkiss Brain Institute, The University of Calgary, 3330 Hospital Dr. NW, Calgary, AB T2N 4N1 Canada
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21
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Kalló I, Omrani A, Meye FJ, de Jong H, Liposits Z, Adan RAH. Characterization of orexin input to dopamine neurons of the ventral tegmental area projecting to the medial prefrontal cortex and shell of nucleus accumbens. Brain Struct Funct 2022; 227:1083-1098. [PMID: 35029758 PMCID: PMC8930802 DOI: 10.1007/s00429-021-02449-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/29/2021] [Indexed: 11/29/2022]
Abstract
Orexin neurons are involved in homeostatic regulatory processes, including arousal and feeding, and provide a major input from the hypothalamus to the ventral tegmental area (VTA) of the midbrain. VTA neurons are a central hub processing reward and motivation and target the medial prefrontal cortex (mPFC) and the shell part of nucleus accumbens (NAcs). We investigated whether subpopulations of dopamine (DA) neurons in the VTA projecting either to the mPFC or the medial division of shell part of nucleus accumbens (mNAcs) receive differential input from orexin neurons and whether orexin exerts differential electrophysiological effects upon these cells. VTA neurons projecting to the mPFC or the mNAcs were traced retrogradely by Cav2-Cre virus and identified by expression of yellow fluorescent protein (YFP). Immunocytochemical analysis showed that a higher proportion of all orexin-innervated DA neurons projected to the mNAcs (34.5%) than to the mPFC (5.2%). Of all sampled VTA neurons projecting either to the mPFC or mNAcs, the dopaminergic (68.3 vs. 79.6%) and orexin-innervated DA neurons (68.9 vs. 64.4%) represented the major phenotype. Whole-cell current clamp recordings were obtained from fluorescently labeled neurons in slices during baseline periods and bath application of orexin A. Orexin similarly increased the firing rate of VTA dopamine neurons projecting to mNAcs (1.99 ± 0.61 Hz to 2.53 ± 0.72 Hz) and mPFC (0.40 ± 0.22 Hz to 1.45 ± 0.56 Hz). Thus, the hypothalamic orexin system targets mNAcs and to a lesser extent mPFC-projecting dopaminergic neurons of the VTA and exerts facilitatory effects on both clusters of dopamine neurons.
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Affiliation(s)
- Imre Kalló
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Eötvös Loránd Research Center, Budapest, 1083, Hungary.,Department of Neuroscience, Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, 1083, Hungary
| | - Azar Omrani
- Department of Translational Neuroscience, UMC Brain Center, University Medical Center Utrecht, Universiteitsweg 100, 3584, Utrecht, The Netherlands
| | - Frank J Meye
- Department of Translational Neuroscience, UMC Brain Center, University Medical Center Utrecht, Universiteitsweg 100, 3584, Utrecht, The Netherlands
| | - Han de Jong
- Department of Translational Neuroscience, UMC Brain Center, University Medical Center Utrecht, Universiteitsweg 100, 3584, Utrecht, The Netherlands
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Eötvös Loránd Research Center, Budapest, 1083, Hungary. .,Department of Neuroscience, Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, 1083, Hungary.
| | - Roger A H Adan
- Department of Translational Neuroscience, UMC Brain Center, University Medical Center Utrecht, Universiteitsweg 100, 3584, Utrecht, The Netherlands. .,Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 40530, Goteborg, Sweden.
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22
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Transcriptional and functional divergence in lateral hypothalamic glutamate neurons projecting to the lateral habenula and ventral tegmental area. Neuron 2021; 109:3823-3837.e6. [PMID: 34624220 DOI: 10.1016/j.neuron.2021.09.020] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/28/2021] [Accepted: 09/10/2021] [Indexed: 01/19/2023]
Abstract
The lateral hypothalamic area (LHA) regulates feeding- and reward-related behavior, but because of its molecular and anatomical heterogeneity, the functions of defined neuronal populations are largely unclear. Glutamatergic neurons within the LHA (LHAVglut2) negatively regulate feeding and appetitive behavior. However, this population comprises transcriptionally distinct and functionally diverse neurons that project to diverse brain regions, including the lateral habenula (LHb) and ventral tegmental area (VTA). To resolve the function of distinct LHAVglut2 populations, we systematically compared projections to the LHb and VTA using viral tracing, single-cell sequencing, electrophysiology, and in vivo calcium imaging. LHAVglut2 neurons projecting to the LHb or VTA are anatomically, transcriptionally, electrophysiologically, and functionally distinct. While both populations encode appetitive and aversive stimuli, LHb projecting neurons are especially sensitive to satiety state and feeding hormones. These data illuminate the functional heterogeneity of LHAVglut2 neurons, suggesting that reward and aversion are differentially processed in divergent efferent pathways.
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23
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Song Y, Li J, Li H, Cai M, Miao D. The role of ventral tegmental area orexinergic afferents in depressive-like behavior in a chronic unpredictable mild stress (CUMS) mouse model. Biochem Biophys Res Commun 2021; 579:22-28. [PMID: 34583191 DOI: 10.1016/j.bbrc.2021.09.062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 09/22/2021] [Indexed: 10/20/2022]
Abstract
Orexin has been implicated in comorbid diseases of depression, making it a promising target for anti-depression treatment. Although orexin neurons exhibit abnormal activity in depression, the neurocircuit mechanism of orexin remains unclear. As one of the important downstream factors of orexin neurons, the ventral tegmental area (VTA) is considered crucial to the mechanism of depression. However, the role of VTA orexinergic afferents in depression remains unclear. In this study, we applied a combination of opto/chemogenetic and neuropharmacology methods to investigate whether the VTA orexinergic afferents participate in the pathogenesis of depression in a chronic unpredictable mild stress (CUMS) mouse model. We found that c-Fos expression in these VTA-projecting orexin neurons specifically decreased in CUMS-treated mice. Optogenetic and chemogenetic activation of orexin terminals in the VTA significantly reversed depressive behavior. Microinjection of orexin-A, but not orexin-B, into the VTA significantly improved depressive-like behavior. Our study provided direct evidence that the VTA orexinergic afferents participate in the mechanism of depression, and the orexin-1 receptor plays a major role.
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Affiliation(s)
- Yunyun Song
- Department of Medical Psychology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jiannan Li
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Huiming Li
- Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Min Cai
- Department of Psychiatry, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Danmin Miao
- Department of Medical Psychology, The Fourth Military Medical University, Xi'an, Shaanxi, China.
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24
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Peleg-Raibstein D, Burdakov D. Do orexin/hypocretin neurons signal stress or reward? Peptides 2021; 145:170629. [PMID: 34416308 DOI: 10.1016/j.peptides.2021.170629] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/04/2021] [Accepted: 08/14/2021] [Indexed: 12/23/2022]
Abstract
Hypothalamic neurons that produce the peptide transmitters orexins/hypocretins (HONs) broadcast their predominantly neuroexcitatory outputs to the entire brain via their extremely wide axonal projections. HONs were originally reported to be activated by food deprivation, and to stimulate arousal, energy expenditure, and eating. This led to extensive studies of HONs in the context of nutrient-sensing and energy balance control. While activation of HONs by body energy depletion continues to be supported by experimental evidence, it has also become clear that HONs are robustly activated not only by nutrient depletion, but also by diverse sensory stimuli (both neutral and those associated with rewarding or aversive events), seemingly unrelated to each other or to energy balance. One theory that could unify these findings is that all these stimuli signal "stress" - defined either as a potentially harmful state, or an awareness of reward deficiency. If HON activity is conceptualized as a cumulative representation of stress, then many of the reported HONs outputs - including EEG arousal, sympathetic activation, place avoidance, and exploratory behaviours - could be viewed as logical stress-counteracting responses. We discuss evidence for and against this unifying theory of HON function, including the alterations in HON activity observed in anxiety and depression disorders. We propose that, in order to orchestrate stress-countering responses, HONs need to coactivate motivation and aversion brain systems, and the impact of HON stimulation on affective states may be perceived as rewarding or aversive depending on the baseline HON activity.
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Affiliation(s)
| | - Denis Burdakov
- Department of Health Sciences and Technology, ETH Zürich, Switzerland.
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25
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Cunha C, Smiley JF, Chuhma N, Shah R, Bleiwas C, Menezes EC, Seal RP, Edwards RH, Rayport S, Ansorge MS, Castellanos FX, Teixeira CM. Perinatal interference with the serotonergic system affects VTA function in the adult via glutamate co-transmission. Mol Psychiatry 2021; 26:4795-4812. [PMID: 32398719 PMCID: PMC7657958 DOI: 10.1038/s41380-020-0763-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 04/07/2020] [Accepted: 04/27/2020] [Indexed: 11/29/2022]
Abstract
Serotonin and dopamine are associated with multiple psychiatric disorders. How they interact during development to affect subsequent behavior remains unknown. Knockout of the serotonin transporter or postnatal blockade with selective serotonin reuptake inhibitors (SSRIs) leads to novelty-induced exploration deficits in adulthood, potentially involving the dopamine system. Here, we show in the mouse that raphe nucleus serotonin neurons activate ventral tegmental area dopamine neurons via glutamate co-transmission and that this co-transmission is reduced in animals exposed postnatally to SSRIs. Blocking serotonin neuron glutamate co-transmission mimics this SSRI-induced hypolocomotion, while optogenetic activation of dopamine neurons reverses this hypolocomotor phenotype. Our data demonstrate that serotonin neurons modulate dopamine neuron activity via glutamate co-transmission and that this pathway is developmentally malleable, with high serotonin levels during early life reducing co-transmission, revealing the basis for the reduced novelty-induced exploration in adulthood due to postnatal SSRI exposure.
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Affiliation(s)
- Catarina Cunha
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA
- Department of Child and Adolescent Psychiatry, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - John F Smiley
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA
- Department of Child and Adolescent Psychiatry, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Nao Chuhma
- Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York, NY, 10032, USA
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Relish Shah
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA
| | - Cynthia Bleiwas
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA
| | - Edenia C Menezes
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA
| | - Rebecca P Seal
- Department of Neurobiology and Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15260, USA
| | - Robert H Edwards
- Departments of Neurology and Physiology, University of California, San Francisco School of Medicine, San Francisco, CA, 94143, USA
| | - Stephen Rayport
- Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York, NY, 10032, USA
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Mark S Ansorge
- Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York, NY, 10032, USA
- Department of Developmental Neuroscience, New York State Psychiatric Institute, New York, NY, 10032, USA
| | - Francisco X Castellanos
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA
- Department of Child and Adolescent Psychiatry, New York University Grossman School of Medicine, New York, NY, 10016, USA
| | - Catia M Teixeira
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, 10962, USA.
- Department of Child and Adolescent Psychiatry, New York University Grossman School of Medicine, New York, NY, 10016, USA.
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Reactivating a positive feedback loop VTA-BLA-NAc circuit associated with positive experience ameliorates the attenuated reward sensitivity induced by chronic stress. Neurobiol Stress 2021; 15:100370. [PMID: 34381852 PMCID: PMC8334743 DOI: 10.1016/j.ynstr.2021.100370] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/20/2021] [Accepted: 07/22/2021] [Indexed: 12/24/2022] Open
Abstract
Both genetic predisposition and life events, particularly life stress, are thought to increase the risk for depression. Reward sensitivity appears to be attenuated in major depressive disorder (MDD), suggesting deficits in reward processing in these patients. We identified the VTA-BLA-NAc circuit as being activated by sex reward, and the VTA neurons that respond to sex reward are mostly dopaminergic. Acute or chronic reactivation of this circuit ameliorates the reward insensitivity induced by chronic restraint stress. Our histological and electrophysiological results show that the VTA neuron subpopulation responding to restraint stress, predominantly GABAergic neurons, inhibits the responsiveness of VTA dopaminergic neurons to reward stimuli, which is probably the mechanism by which stress modulates the reward processing neural circuits and subsequently disrupts reward-related behaviours. Furthermore, we found that the VTA-BLA-NAc circuit is a positive feedback loop. Blocking the projections from the BLA to the NAc associated with sex reward increases the excitability of VTA GABAergic neurons and decreases the excitability of VTA dopaminergic neurons, while activating this pathway decreases the excitability of VTA GABAergic neurons and increases the excitability of VTA dopaminergic neurons, which may be the cellular mechanism by which the VTA-BLA-NAc circuit associated with sex reward ameliorates the attenuated reward sensitivity induced by chronic stress.
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Abstract
As ultraprocessed foods (i.e., foods composed of mostly cheap industrial sources of dietary energy and nutrients plus additives) have become more abundant in our food supply, rates of obesity and diet-related disease have increased simultaneously. Food addiction has emerged as a phenotype of significant empirical interest within the past decade, conceptualized most commonly as a substance-based addiction to ultraprocessed foods. We detail (a) how approaches used to understand substance-use disorders may be applicable for operationalizing food addiction, (b) evidence for the reinforcing potential of ingredients in ultraprocessed foods that may drive compulsive consumptions, (c) the utility of conceptualizing food addiction as a substance-use disorder versus a behavioral addiction, and (d) clinical and policy implications that may follow if ultraprocessed foods exhibit an addictive potential. Broadly, the existing literature suggests biological and behavioral parallels between food addiction and substance addictions, with ultraprocessed foods high in both added fat and refined carbohydrates being most implicated in addictive-like eating. Future research priorities are also discussed, including the need for longitudinal studies and the potential negative impact of addictive ultraprocessed foods on children. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Ashley N Gearhardt
- Department of Psychology, University of Michigan, Ann Arbor, Michigan 48109, USA;
| | - Erica M Schulte
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA;
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Clare K, Pan C, Kim G, Park K, Zhao J, Volkow ND, Lin Z, Du C. Cocaine Reduces the Neuronal Population While Upregulating Dopamine D2-Receptor-Expressing Neurons in Brain Reward Regions: Sex-Effects. Front Pharmacol 2021; 12:624127. [PMID: 33912043 PMCID: PMC8072657 DOI: 10.3389/fphar.2021.624127] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/08/2021] [Indexed: 02/03/2023] Open
Abstract
Addiction to cocaine is associated with dysfunction of the dopamine mesocortical system including impaired dopamine-2 receptor (D2r) signaling. However, the effects of chronic cocaine on neuronal adaptations in this system have not been systematically examined and data available is mostly from males. Here, we investigated changes in the total neuronal density and relative concentration of D2r-expressing neurons in the medial prefrontal cortex (mPFC), dorsal striatum (Dstr), nucleus accumbens (NAc), and ventral tegmental area (VTA) in both male and female mice passively exposed to cocaine for two weeks. In parallel experiments, we measured mRNA levels for Drd2 and for opioid peptides (mPenk and mPdyn). Through a combination of large field of view fluorescent imaging with BAC transgenic D2r-eGFP mice and immunostaining, we observed that cocaine exposed mice had a higher density of D2r-positive cells that was most prominent in mPFC and VTA and larger for females than for males. This occurred amidst an overall significant decrease in neuronal density (measured with NeuN) in both sexes. However, increases in Drd2 mRNA levels with cocaine were only observed in mPFC and Dstr in females, which might reflect the limited sensitivity of the method. Our findings, which contrast with previous findings of cocaine-induced downregulation of D2r binding availability, could reflect a phenotypic shift in neurons that did not previously express Drd2 and merits further investigation. Additionally, the neuronal loss particularly in mPFC with chronic cocaine might contribute to the cognitive impairments observed with cocaine use disorder.
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Affiliation(s)
- Kevin Clare
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States
| | - Chelsea Pan
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States
| | - Gloria Kim
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States
| | - Kicheon Park
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States
| | - Juan Zhao
- Laboratory of Psychiatric Neurogenomics, Basic Neuroscience Division, McLean Hospital, Belmont, MA, United States
| | - Nora D Volkow
- National Institute on Drug Abuse, Bethesda, MD, United States
| | - Zhicheng Lin
- Laboratory of Psychiatric Neurogenomics, Basic Neuroscience Division, McLean Hospital, Belmont, MA, United States
| | - Congwu Du
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, United States
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Concetti C, Burdakov D. Orexin/Hypocretin and MCH Neurons: Cognitive and Motor Roles Beyond Arousal. Front Neurosci 2021; 15:639313. [PMID: 33828450 PMCID: PMC8019792 DOI: 10.3389/fnins.2021.639313] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 03/01/2021] [Indexed: 02/01/2023] Open
Abstract
The lateral hypothalamus (LH) is classically implicated in sleep-wake control. It is the main source of orexin/hypocretin and melanin-concentrating hormone (MCH) neuropeptides in the brain, which have been both implicated in arousal state switching. These neuropeptides are produced by non-overlapping LH neurons, which both project widely throughout the brain, where release of orexin and MCH activates specific postsynaptic G-protein-coupled receptors. Optogenetic manipulations of orexin and MCH neurons during sleep indicate that they promote awakening and REM sleep, respectively. However, recordings from orexin and MCH neurons in awake, moving animals suggest that they also act outside sleep/wake switching. Here, we review recent studies showing that both orexin and MCH neurons can rapidly (sub-second-timescale) change their firing when awake animals experience external stimuli, or during self-paced exploration of objects and places. However, the sensory-behavioral correlates of orexin and MCH neural activation can be quite different. Orexin neurons are generally more dynamic, with about 2/3rds of them activated before and during self-initiated running, and most activated by sensory stimulation across sensory modalities. MCH neurons are activated in a more select manner, for example upon self-paced investigation of novel objects and by certain other novel stimuli. We discuss optogenetic and chemogenetic manipulations of orexin and MCH neurons, which combined with pharmacological blockade of orexin and MCH receptors, imply that these rapid LH dynamics shape fundamental cognitive and motor processes due to orexin and MCH neuropeptide actions in the awake brain. Finally, we contemplate whether the awake control of psychomotor brain functions by orexin and MCH are distinct from their “arousal” effects.
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Affiliation(s)
- Cristina Concetti
- Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland
| | - Denis Burdakov
- Department of Health Sciences and Technology, ETH Zürich, Zurich, Switzerland
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30
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Siahposht-Khachaki A, Nazari-Serenjeh F, Rezaee L, Haghparast A, Rashvand M, Haghparast A. Dopaminergic receptors in the ventral tegmental area modulated the lateral hypothalamic stimulation-induced antinociception in an animal model of tonic pain. Neurosci Lett 2021; 751:135827. [PMID: 33727128 DOI: 10.1016/j.neulet.2021.135827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 02/21/2021] [Accepted: 03/08/2021] [Indexed: 11/26/2022]
Abstract
The role of the ventral tegmental area (VTA) and the lateral hypothalamus (LH) in the modulation of formalin-induced nociception is well documented individually. The present study aimed to investigate the role of dopamine receptors of the VTA in the modulation of the LH stimulation-induced antinociception during both phases of the formalin test as an animal model of tonic pain. In this study, male Wistar rats were unilaterally implanted with two guide cannulae in the VTA and LH. In two separate groups, animals received different doses (0.25, 1, and 4 μg/rat) of D1- or D2-like dopamine receptor antagonists (SCH-23,390 or Sulpiride, respectively) into the VTA before intra-LH injection of carbachol (22.83 ng/rat) following formalin injection (50 μL; s.c.) into their contralateral hind paws. The blockade of these two receptors reduced intra-LH carbachol-induced antinociception during both phases of the formalin test. This reduction during the late phase of the formalin test was more than that of the early phase. The results indicated that LH stimulation-induced antinociception was mediated by D1- and D2-like dopamine receptors in the VTA, and so, the neural pathway projecting from the LH to the VTA contributes to the modulation of formalin-induced nociception in the rats.
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Affiliation(s)
- Ali Siahposht-Khachaki
- Department of Physiology and Pharmacology, Mazandaran University of Medical Sciences, Ramsar International Branch, Sari, Iran
| | | | - Laleh Rezaee
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mina Rashvand
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Wu G, Xu X, Ye F, Shu H. Effects of processed Aconiti tuber on the extinction and reinstatement of morphine-induced conditioned place preference in rats. JOURNAL OF ETHNOPHARMACOLOGY 2021; 267:113524. [PMID: 33129945 DOI: 10.1016/j.jep.2020.113524] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 09/10/2020] [Accepted: 10/26/2020] [Indexed: 06/11/2023]
Abstract
AIM OF THE STUDY To investigate the effect of processed Aconiti tuber (PAT) administered during or after the time of conditioned place preference (CPP) training on the extinction and reinstatement of morphine-priming CPP in rats. The dynorphin level in rats' nucleus accumbens (NAc) is detected as a target of the Dynorphin/Kappa Opioid Receptor (KOR) system for the possible mechanism. MATERIALS AND METHODS Eight groups of rats were subcutaneously (s.c.) injected with morphine (10mg/kg) (on days 2,4,6,8) or saline (1ml/kg) (on days 3,5,7,9) alternately for 8 days. Five groups, including groups (Mor + Water, Mor + PAT (1.0/3.0g/kg) (S) and Sal + PAT(1.0/3.0g/kg)), were orally given distilled water or PAT 1.0 or 3.0 g/kg daily on days 1-8 during CPP training while other three groups, including groups (Sal + Water and Mor + PAT (1.0/3.0g/kg)(P), were given distilled water or PAT daily from day 10 until CPP was extinct. Morphine 1mg/kg (s.c.) was used to reinstate the extinct CPP and the CPP scores were recorded. The dynorphin concentration in nucleus accumbens (NAc) was assayed by radioimmunoassay after the last CPP measurement. RESULTS 1) The CPP extinction shortened in Mor + PAT (1.0/3.0 g/kg) (S) groups but extended in Mor + PAT (1.0/3.0 g/kg)(P) groups. 2) Morphine-priming CPP did not change either in Mor + PAT (1.0/3.0 g/kg) (S) or Mor + PAT (1.0/3.0 g/kg)(P) groups. 3) The dynorphin concentration in NAc increased either in Mor + PAT (1.0/3.0 g/kg)(S) or Mor + PAT (1.0/3.0 g/kg)(P) groups. CONCLUSIONS 1) PAT shortened the extinction from morphine induced CPP when administrated before CPP acquisition, whereas it extended the extinction when administrated after CPP formation. 2) PAT administrated during or after CPP training did not affect morphine-priming reinstatement of morphine induced CPP. 3) Dynorphin/KOR system might be a target to regulate morphine-induced CPP extinction but not reinstatement.
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Affiliation(s)
- Guiyun Wu
- Department of Anesthesiology, Affiliated Sun Yat-sen Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiaoying Xu
- Department of Anesthesiology, Affiliated Sun Yat-sen Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Fang Ye
- Department of Anesthesiology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Haihua Shu
- Department of Anesthesiology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, PR China; The Second School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong, PR China.
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32
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Orexin-A differentially modulates inhibitory and excitatory synaptic transmission in rat inner retina. Neuropharmacology 2021; 187:108492. [PMID: 33582153 DOI: 10.1016/j.neuropharm.2021.108492] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 01/08/2021] [Accepted: 02/06/2021] [Indexed: 11/21/2022]
Abstract
In this work, modulation by orexin-A of the release of glutamate and GABA from bipolar and amacrine cells respectively was studied by examining the effects of the neuropeptide on miniature excitatory postsynaptic currents (mEPSCs) and miniature inhibitory postsynaptic currents (mIPSCs) of rat retinal ganglion cells (GCs). Using RNAscope in situ hybridization in combination with immunohistochemistry, we showed positive signals for orexin receptor-1 (OX1R) mRNA in the bipolar cell terminals and those for orexin receptor-2 (OX2R) mRNA in the amacrine cell terminals. With whole-cell patch-clamp recordings in rat retinal slices, we demonstrated that application of orexin-A reduced the interevent interval of mEPSCs of GCs through OX1R. However, it increased the interevent interval of mIPSCs, mediated by GABAA receptors, through OX2R. Furthermore, orexin-A-induced reduction of mEPSC interevent interval was abolished by the application of PI-PLC inhibitors or PKC inhibitors. In contrast, orexin-A-induced increase of GABAergic mIPSC interevent interval was mimicked by 8-Br-cAMP or an adenylyl cyclase activator, but was eliminated by PKA antagonists. Finally, application of nimodipine, an L-type Ca2+ channel blocker, increased both mEPSC and mIPSC interevent interval, and co-application of orexin-A no longer changed the mEPSCs and mIPSCs. We conclude that orexin-A increases presynaptic glutamate release onto GCs by activating L-type Ca2+ channels in bipolar cells, a process that is mediated by an OX1R/PI-PLC/PKC signaling pathway. However, orexin-A decreases presynaptic GABA release onto GCs by inhibiting L-type Ca2+ channels in amacrine cells, a process that is mediated by an OX2R/cAMP-PKA signaling pathway.
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Klockars A, Levine AS, Head MA, Perez-Leighton CE, Kotz CM, Olszewski PK. Impact of Gut and Metabolic Hormones on Feeding Reward. Compr Physiol 2021; 11:1425-1447. [PMID: 33577129 DOI: 10.1002/cphy.c190042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Ingestion of food activates a cascade of endocrine responses (thereby reflecting a contemporaneous feeding status) that include the release of hormones from the gastrointestinal (GI) tract, such as cholecystokinin (CCK), glucagonlike peptide YY (PYY), peptide PP, and oleoylethanolamide, as well as suppression of ghrelin secretion. The pancreas and adipose tissue, on the other hand, release hormones that serve as a measure of the current metabolic state or the long-term energy stores, that is, insulin, leptin, and adiponectin. It is well known and intuitively understandable that these hormones target either directly (by crossing the blood-brain barrier) or indirectly (e.g., via vagal input) the "homeostatic" brainstem-hypothalamic pathways involved in the regulation of appetite. The current article focuses on yet another target of the metabolic and GI hormones that is critical in inducing changes in food intake, namely, the reward system. We discuss the physiological basis of this functional interaction, its importance in the control of appetite, and the impact that disruption of this crosstalk has on energy intake in select physiological and pathophysiological states. We conclude that metabolic and GI hormones have a capacity to strengthen or weaken a response of the reward system to a given food, and thus, they are fundamental in ensuring that feeding reward is plastic and dependent on the energy status of the organism. © 2021 American Physiological Society. Compr Physiol 11:1425-1447, 2021.
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Affiliation(s)
- Anica Klockars
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | - Allen S Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, Minnesota, USA
| | - Mitchell A Head
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand
| | | | - Catherine M Kotz
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, Minnesota, USA.,Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, Minnesota, USA
| | - Pawel K Olszewski
- Faculty of Science and Engineering, University of Waikato, Hamilton, New Zealand.,Department of Food Science and Nutrition, University of Minnesota, St. Paul, Minnesota, USA.,Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, Minnesota, USA
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Tunisi L, D'Angelo L, Fernández-Rilo AC, Forte N, Piscitelli F, Imperatore R, de Girolamo P, Di Marzo V, Cristino L. Orexin-A/Hypocretin-1 Controls the VTA-NAc Mesolimbic Pathway via Endocannabinoid-Mediated Disinhibition of Dopaminergic Neurons in Obese Mice. Front Synaptic Neurosci 2021; 13:622405. [PMID: 33613258 PMCID: PMC7890184 DOI: 10.3389/fnsyn.2021.622405] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 01/11/2021] [Indexed: 01/27/2023] Open
Abstract
Disinhibition of orexin-A/hypocretin-1 (OX-A) release occurs to several output areas of the lateral hypothalamus (LH) in the brain of leptin knockout obese ob/ob mice. In this study, we have investigated whether a similar increase of OX-A release occurs to the ventral tegmental area (VTA), an orexinergic LH output area with functional effects on dopaminergic signaling at the mesolimbic circuit. By confocal and correlative light and electron microscopy (CLEM) morphological studies coupled to molecular, biochemical, and pharmacological approaches, we investigated OX-A-mediated dopaminergic signaling at the LH-VTA-nucleus accumbens (NAc) pathway in obese ob/ob mice compared to wild-type (wt) lean littermates. We found an elevation of OX-A trafficking and release to the VTA of ob/ob mice and consequent orexin receptor-1 (OX1R)-mediated over-activation of dopaminergic (DA) neurons via phospholipase C (PLC)/diacylglycerol lipase (DAGL-α)-induced biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG). In fact, by retrograde signaling to cannabinoid receptor type 1 (CB1R) at inhibitory inputs to DA neurons, 2-AG inhibited GABA release thus inducing an increase in DA concentration in the VTA and NAc of ob/ob mice. This effect was prevented by the OX1R antagonist SB-334867 (30 mg/Kg, i.p.), or the CB1R antagonist AM251 (10 mg/Kg, i.p.) and mimicked by OX-A injection (40 μg/Kg, i.p.) in wt lean mice. Enhanced DA signaling to the NAc in ob/ob mice, or in OX-A-injected wt mice, was accompanied by β-arrestin2-mediated desensitization of dopamine D2 receptor (D2R) in a manner prevented by SB-334867 or the D2R antagonist L741 (1.5 mg/Kg, i.p.). These results further support the role of OX-A signaling in the control of neuroadaptive responses, such as compulsive reward-seeking behavior or binge-like consumption of high palatable food, and suggest that aberrant OX-A trafficking to the DA neurons in the VTA of ob/ob mice influences the D2R response at NAc, a main target area of the mesolimbic pathway, via 2-AG/CB1-mediated retrograde signaling.
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Affiliation(s)
- Lea Tunisi
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Italy.,Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy
| | - Livia D'Angelo
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy
| | - Alba Clara Fernández-Rilo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Italy
| | - Nicola Forte
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Italy.,Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, Université Laval, Québec City, QC, Canada
| | - Fabiana Piscitelli
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Italy
| | - Roberta Imperatore
- Department of Sciences and Technologies, University of Sannio, Benevento, Italy
| | - Paolo de Girolamo
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Italy.,Canada Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health, Université Laval, Québec City, QC, Canada.,Heart and Lung Research Institute of Université Laval, and Institute for Nutrition and Functional Foods, Université Laval, Québec City, QC, Canada
| | - Luigia Cristino
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council, Pozzuoli, Italy
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35
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Differential importance of nucleus accumbens Ox1Rs and AMPARs for female and male mouse binge alcohol drinking. Sci Rep 2021; 11:231. [PMID: 33420199 PMCID: PMC7794293 DOI: 10.1038/s41598-020-79935-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 12/15/2020] [Indexed: 02/06/2023] Open
Abstract
Alcohol use disorder exhausts substantial social and economic costs, with recent dramatic increases in female problem drinking. Thus, it is critically important to understand signaling differences underlying alcohol consumption across the sexes. Orexin-1 receptors (Ox1Rs) can strongly promote motivated behavior, and we previously identified Ox1Rs within nucleus accumbens shell (shell) as crucial for driving binge intake in higher-drinking male mice. Here, shell Ox1R inhibition did not alter female mouse alcohol drinking, unlike in males. Also, lower dose systemic Ox1R inhibition reduced compulsion-like alcohol intake in both sexes, indicating that female Ox1Rs can drive some aspects of pathological consumption, and higher doses of systemic Ox1R inhibition (which might have more off-target effects) reduced binge drinking in both sexes. In contrast to shell Ox1Rs, inhibiting shell calcium-permeable AMPA receptors (CP-AMPARs) strongly reduced alcohol drinking in both sexes, which was specific to alcohol since this did not reduce saccharin intake in either sex. Our results together suggest that the shell critically regulates binge drinking in both sexes, with shell CP-AMPARs supporting intake in both sexes, while shell Ox1Rs drove drinking only in males. Our findings provide important new information about sex-specific and -general mechanisms that promote binge alcohol intake and possible targeted therapeutic interventions.
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Tejeda HA, Wang H, Flores RJ, Yarur HE. Dynorphin/Kappa-Opioid Receptor System Modulation of Cortical Circuitry. Handb Exp Pharmacol 2021; 271:223-253. [PMID: 33580392 DOI: 10.1007/164_2021_440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cortical circuits control a plethora of behaviors, from sensation to cognition. The cortex is enriched with neuropeptides and receptors that play a role in information processing, including opioid peptides and their cognate receptors. The dynorphin (DYN)/kappa-opioid receptor (KOR) system has been implicated in the processing of sensory and motivationally-charged emotional information and is highly expressed in cortical circuits. This is important as dysregulation of DYN/KOR signaling in limbic and cortical circuits has been implicated in promoting negative affect and cognitive deficits in various neuropsychiatric disorders. However, research investigating the role of this system in controlling cortical circuits and computations therein is limited. Here, we review the (1) basic anatomy of cortical circuits, (2) anatomical architecture of the cortical DYN/KOR system, (3) functional regulation of cortical synaptic transmission and microcircuit function by the DYN/KOR system, (4) regulation of behavior by the cortical DYN/KOR system, (5) implications for the DYN/KOR system for human health and disease, and (6) future directions and unanswered questions for the field. Further work elucidating the role of the DYN/KOR system in controlling cortical information processing and associated behaviors will be of importance to increasing our understanding of principles underlying neuropeptide modulation of cortical circuits, mechanisms underlying sensation and perception, motivated and emotional behavior, and cognition. Increased emphasis in this area of study will also aid in the identification of novel ways to target the DYN/KOR system to treat neuropsychiatric disorders.
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Affiliation(s)
- Hugo A Tejeda
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| | - Huikun Wang
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Rodolfo J Flores
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Hector E Yarur
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
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Blockade of orexin receptors in the ventral tegmental area reduced the extinction period of the lateral hypothalamic-induced conditioned place preference in rats. Behav Pharmacol 2020; 32:54-61. [PMID: 33399296 DOI: 10.1097/fbp.0000000000000602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The orexinergic connection between the lateral hypothalamus (LH) and the ventral tegmental area (VTA) is involved in modulating the reward circuit. The conditioned place preference (CPP) can be induced by microinjection of carbachol, a cholinergic agonist, into the LH. The current research was conducted to understand whether intra-VTA orexin receptors (OXRs) could influence the duration of the extinction period or maintenance of the intra-LH carbachol-induced CPP. To this end, the rats unilaterally received intra-LH carbachol (250 nM) within a 3-day conditioning period. Animals that have already passed the conditioning test were unilaterally administered by intra-VTA microinjection of SB334867, an OX1R antagonist, or TCS OX2 29, an OX2R antagonist during the extinction phase of the LH stimulation-induced CPP. For the first time, our data indicated that daily intra-VTA administration of either SB334867 (30 nM) or TCS OX2 29 (10 and 30 nM) during the extinction period decreased the maintenance of intra-LH carbachol-induced CPP. In conclusion, OXRs in the VTA play crucial roles in the maintenance of reward processes.
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Mahmoudi M, Maleki-Roveshti M, Karimi-Haghighi S, Haghparast A. Chemical stimulation of the lateral hypothalamus induced seeking behaviors in rats: Involvement of orexin receptors in the ventral tegmental area. Eur J Pharmacol 2020; 886:173433. [DOI: 10.1016/j.ejphar.2020.173433] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 07/26/2020] [Accepted: 07/26/2020] [Indexed: 11/16/2022]
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Lee J, Raycraft L, Johnson AW. The dynamic regulation of appetitive behavior through lateral hypothalamic orexin and melanin concentrating hormone expressing cells. Physiol Behav 2020; 229:113234. [PMID: 33130035 DOI: 10.1016/j.physbeh.2020.113234] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 02/07/2023]
Abstract
The lateral hypothalamic area (LHA) is a heterogeneous brain structure extensively studied for its potent role in regulating energy balance. The anatomical and molecular diversity of the LHA permits the orchestration of responses to energy sensing cues from the brain and periphery. Two of the primary cell populations within the LHA associated with integration of this information are Orexin (ORX) and Melanin Concentrating Hormone (MCH). While both of these non-overlapping populations exhibit orexigenic properties, the activities of these two systems support feeding behavior through contrasting mechanisms. We describe the anatomical and functional properties as well as interaction with other neuropeptides and brain reward and hedonic systems. Specific outputs relating to arousal, food seeking, feeding, and metabolism are coordinated through these mechanisms. We then discuss how both the ORX and MCH systems harmonize in a divergent yet overall cooperative manner to orchestrate feeding behavior through transitions between various appetitive states, and thus offer novel insights into LHA allostatic control of appetite.
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Affiliation(s)
| | | | - Alexander W Johnson
- Department of Psychology; Neuroscience Program, Michigan State University, East Lansing.
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Chemogenetic Manipulation of Dopamine Neurons Dictates Cocaine Potency at Distal Dopamine Transporters. J Neurosci 2020; 40:8767-8779. [PMID: 33046544 DOI: 10.1523/jneurosci.0894-20.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 09/18/2020] [Accepted: 09/27/2020] [Indexed: 12/21/2022] Open
Abstract
The reinforcing efficacy of cocaine is largely determined by its capacity to inhibit the dopamine transporter (DAT), and emerging evidence suggests that differences in cocaine potency are linked to several symptoms of cocaine use disorder. Despite this evidence, the neural processes that govern cocaine potency in vivo remain unclear. In male rats, we used chemogenetics with intra-VTA microinfusions of the agonist clozapine-n-oxide to bidirectionally modulate dopamine neurons. Using ex vivo fast scan cyclic voltammetry, pharmacological probes of the DAT, biochemical assessments of DAT membrane availability and phosphorylation, and cocaine self-administration, we tested the effects of chemogenetic manipulations on cocaine potency at distal DATs in the nucleus accumbens as well as the behavioral economics of cocaine self-administration. We discovered that chemogenetic manipulation of dopamine neurons produced rapid, bidirectional modulation of cocaine potency at DATs in the nucleus accumbens. We then provided evidence that changes in cocaine potency are associated with alterations in DAT affinity for cocaine and demonstrated that this change in affinity coincides with DAT conformation biases and changes in DAT phosphorylation state. Finally, we showed that chemogenetic manipulation of dopamine neurons alters cocaine consumption in a manner consistent with changes in cocaine potency at distal DATs. Based on the spatial and temporal constraints inherent to our experimental design, we posit that changes in cocaine potency are driven by alterations in dopamine neuron activity. When considered together, these observations provide a novel mechanism through which GPCRs regulate cocaine's pharmacological and behavioral effects.SIGNIFICANCE STATEMENT Differences in the pharmacological effects of cocaine are believed to influence the development and progression of cocaine use disorder. However, the biological and physiological processes that determine sensitivity to cocaine remain unclear. In this work, we use a combination of chemogenetics, fast scan cyclic voltammetry, pharmacology, biochemistry, and cocaine self-administration with economic demand analysis to demonstrate a novel mechanism by which cocaine potency is determined in vivo These studies identify a novel process by which the pharmacodynamics of cocaine are derived in vivo, and thus this work has widespread implications for understanding the mechanisms that regulate cocaine consumption across stages of addiction.
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Ahmadi-Soleimani SM, Mianbandi V, Azizi H, Azhdari-Zarmehri H, Ghaemi-Jandabi M, Abbasi-Mazar A, Mohajer Y, Darana SP. Coregulation of sleep-pain physiological interplay by orexin system: An unprecedented review. Behav Brain Res 2020; 391:112650. [DOI: 10.1016/j.bbr.2020.112650] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/28/2020] [Accepted: 04/08/2020] [Indexed: 12/14/2022]
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Pantazis CB, James MH, Bentzley BS, Aston‐Jones G. The number of lateral hypothalamus orexin/hypocretin neurons contributes to individual differences in cocaine demand. Addict Biol 2020; 25:e12795. [PMID: 31297913 DOI: 10.1111/adb.12795] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/25/2019] [Accepted: 05/22/2019] [Indexed: 12/11/2022]
Abstract
Lateral hypothalamus (LH) orexin neuron signaling has been implicated in the motivation to seek and take drugs of abuse. The number of LH orexin neurons has been shown to be upregulated with exposure to drugs of abuse. We sought to determine if the number of LH orexin neurons related to individual differences in motivation (demand) for cocaine in our behavioral economics (BE) paradigm, and whether knockdown of these cells predicted changes in economic demand. We quantified LH orexin cell numbers in animals immediately following our BE paradigm, as well as after a 2-week period of abstinence, to relate the number of LH orexin cells to economic demand for cocaine. We also knocked down LH orexin expression with an orexin morpholino antisense to determine how reduced orexin numbers impacted cocaine demand. We found that animals with greater baseline motivation for cocaine (lower demand elasticity) had more LH orexin neurons. Following a 2-week abstinence from cocaine, the number of LH orexin neurons predicted economic demand for cocaine prior to abstinence, indicating that orexin expression is a persistent marker for demand. Reducing LH orexin cell numbers with antisense decreased motivation for cocaine (increased demand elasticity) without affecting baseline consumption. In addition, the number of spared LH orexin neurons after antisense treatment correlated with individual motivation for cocaine. These studies point to a role for the endogenous number of LH orexin neurons in individual differences in motivation for cocaine.
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Affiliation(s)
- Caroline B. Pantazis
- Brain Health Institute Rutgers University/Rutgers Biomedical and Health Sciences Piscataway New Jersey USA
| | - Morgan H. James
- Brain Health Institute Rutgers University/Rutgers Biomedical and Health Sciences Piscataway New Jersey USA
- Florey Institute for Neuroscience and Mental Health Parkville Australia
| | - Brandon S. Bentzley
- Department of Psychiatry and Behavioral Sciences Stanford University Stanford California USA
| | - Gary Aston‐Jones
- Brain Health Institute Rutgers University/Rutgers Biomedical and Health Sciences Piscataway New Jersey USA
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Matini T, Haghparast A, Rezaee L, Salehi S, Tehranchi A, Haghparast A. Role of Dopaminergic Receptors Within the Ventral Tegmental Area in Antinociception Induced by Chemical Stimulation of the Lateral Hypothalamus in an Animal Model of Orofacial Pain. J Pain Res 2020; 13:1449-1460. [PMID: 32606911 PMCID: PMC7304680 DOI: 10.2147/jpr.s255250] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 06/03/2020] [Indexed: 12/13/2022] Open
Abstract
Introduction The ventral tegmental area (VTA), as one of the classical components of the brain reward circuitry, shares large neural networks with the pain processing system. We previously showed the role of VTA dopamine receptors in modulation of lateral hypothalamus (LH)-induced antinociception in acute pain conditions. However, considering the fact that the neural systems involved in the mediation of tonic pain are not the same as those that mediate phasic pain. In the present study, we aimed to examine the role of intra-VTA dopamine receptors in LH-induced antinociceptive responses during tonic orofacial pain conditions. Methods Male Wistar rats weighing 230-250 g were implanted with two separate cannulae into the LH and VTA on the same side. Different solutions of carbachol (62.5, 125 and 250 nM), as a non-selective cholinergic receptor agonist that activates the LH projecting neurons, were microinjected into the LH. In the other groups, D1-like dopamine receptor antagonist, SCH-23390 (0.25, 1 and 4 µg/03 µL saline) or D2-like dopamine receptor antagonist, Sulpiride (0.25, 1 and 4 µg/0.3 µL DMSO 12%) were microinjected into VTA, 5 min prior intra-LH carbachol (250 nM), then subjected to orofacial formalin test. Intra-LH carbachol microinjection dose-dependently attenuated biphasic orofacial pain. Results Intra-VTA administration of SCH-23390 or Sulpiride dose-dependently decreased intra-LH carbachol-induced antinociception during both phases of orofacial formalin test with further effects in the late phase. Discussion The findings suggest that chemical stimulation of the LH by carbachol possibly activates the orexin projecting neurons and subsequently, the VTA dopaminergic neurons involved in the orofacial pain modulation. Detecting such neural circuitry offers an alternative approach in the development of more efficient therapies for such debilitating pain conditions.
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Affiliation(s)
- Tina Matini
- School of Dentistry, International Branch of Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Haghparast
- School of Dentistry, International Branch of Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Laleh Rezaee
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sakineh Salehi
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Medicine, Ardabil Medical Sciences Branch, Islamic Azad University, Ardabil, Iran
| | - Azita Tehranchi
- Dental Research Center, Research Institute of Dental Sciences, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Perez-Bonilla P, Santiago-Colon K, Leinninger GM. Lateral hypothalamic area neuropeptides modulate ventral tegmental area dopamine neurons and feeding. Physiol Behav 2020; 223:112986. [PMID: 32492498 DOI: 10.1016/j.physbeh.2020.112986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 05/19/2020] [Accepted: 05/26/2020] [Indexed: 01/26/2023]
Abstract
Understanding how the brain coordinates energy status with the motivation to eat is crucial to identify strategies to improve disordered body weight. The ventral tegmental area (VTA), known as the core of the mesolimbic system, is of particular interest in this regard because it controls the motivation to consume palatable, calorie-dense foods and to engage in volitional activity. The VTA is largely composed of dopamine (DA) neurons, but modulating these DA neurons has been alternately linked with promoting and suppressing feeding, suggesting heterogeneity in their function. Subsets of VTA DA neurons have recently been described based on their anatomical distribution, electrophysiological features, connectivity and molecular expression, but to date there are no signatures to categorize how DA neurons control feeding. Assessing the neuropeptide receptors expressed by VTA DA neurons may be useful in this regard, as many neuropeptides mediate anorexic or orexigenic responses. In particular, the lateral hypothalamic area (LHA) releases a wide variety of feeding-modulating neuropeptides to the VTA. Since VTA neurons intercept LHA neuropeptides known to either evoke or suppress feeding, expression of the cognate neuropeptide receptors within the VTA may point to VTA DA neuronal mechanisms to promote or suppress feeding, respectively. Here we review the role of the VTA in energy balance and the LHA neuropeptide signaling systems that act in the VTA, whose receptors might be used to classify how VTA DA neurons contribute to energy balance.
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Affiliation(s)
- Patricia Perez-Bonilla
- Neuroscience Graduate Program, USA; Pharmacology and Toxicology Graduate Program, USA; Michigan State University, East Lansing, MI 48114, USA
| | - Krystal Santiago-Colon
- Department of Biology, University of Puerto Rico - Cayey, USA; Bridge to the PhD in Neuroscience Program, USA
| | - Gina M Leinninger
- Department of Physiology, USA; Michigan State University, East Lansing, MI 48114, USA.
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A VTA to Basal Amygdala Dopamine Projection Contributes to Signal Salient Somatosensory Events during Fear Learning. J Neurosci 2020; 40:3969-3980. [PMID: 32277045 DOI: 10.1523/jneurosci.1796-19.2020] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 03/25/2020] [Accepted: 03/26/2020] [Indexed: 01/02/2023] Open
Abstract
The amygdala is a brain area critical for the formation of fear memories. However, the nature of the teaching signal(s) that drive plasticity in the amygdala are still under debate. Here, we use optogenetic methods to investigate the contribution of ventral tegmental area (VTA) dopamine neurons to auditory-cued fear learning in male mice. Using anterograde and retrograde labeling, we found that a sparse and relatively evenly distributed population of VTA neurons projects to the basal amygdala (BA). In vivo optrode recordings in behaving mice showed that many VTA neurons, among them putative dopamine neurons, are excited by footshocks, and acquire a response to auditory stimuli during fear learning. Combined cfos imaging and retrograde labeling in dopamine transporter (DAT) Cre mice revealed that a large majority of BA projectors (>95%) are dopamine neurons, and that BA projectors become activated by the tone-footshock pairing of fear learning protocols. Finally, silencing VTA dopamine neurons, or their axon terminals in the BA during the footshock, reduced the strength of fear memory as tested 1 d later, whereas silencing the VTA-central amygdala (CeA) projection had no effect. Thus, VTA dopamine neurons projecting to the BA contribute to fear memory formation, by coding for the saliency of the footshock event and by signaling such events to the basal amygdala.SIGNIFICANCE STATEMENT Powerful mechanisms of fear learning have evolved in animals and humans to enable survival. During fear conditioning, a sensory cue, such as a tone (the conditioned stimulus), comes to predict an innately aversive stimulus, such as a mild footshock (the unconditioned stimulus). A brain representation of the unconditioned stimulus must act as a teaching signal to instruct plasticity of the conditioned stimulus representation in fear-related brain areas. Here we show that dopamine neurons in the VTA that project to the basal amygdala contribute to such a teaching signal for plasticity, thereby facilitating the formation of fear memories. Knowledge about the role of dopamine in aversively motivated plasticity might allow further insights into maladaptive plasticities that underlie anxiety and post-traumatic stress disorders in humans.
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Hulme H, Fridjonsdottir E, Gunnarsdottir H, Vallianatou T, Zhang X, Wadensten H, Shariatgorji R, Nilsson A, Bezard E, Svenningsson P, Andrén PE. Simultaneous mass spectrometry imaging of multiple neuropeptides in the brain and alterations induced by experimental parkinsonism and L-DOPA therapy. Neurobiol Dis 2020; 137:104738. [DOI: 10.1016/j.nbd.2020.104738] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/20/2019] [Accepted: 01/08/2020] [Indexed: 12/11/2022] Open
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St Laurent R, Martinez Damonte V, Tsuda AC, Kauer JA. Periaqueductal Gray and Rostromedial Tegmental Inhibitory Afferents to VTA Have Distinct Synaptic Plasticity and Opiate Sensitivity. Neuron 2020; 106:624-636.e4. [PMID: 32191871 DOI: 10.1016/j.neuron.2020.02.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 10/01/2019] [Accepted: 02/25/2020] [Indexed: 12/16/2022]
Abstract
The ventral tegmental area (VTA) is a major target of addictive drugs and receives multiple GABAergic projections originating outside the VTA. We describe differences in synaptic plasticity and behavior when optogenetically driving two opiate-sensitive GABAergic inputs to the VTA, the rostromedial tegmental nucleus (RMTg), and the periaqueductal gray (PAG). Activation of GABAergic RMTg terminals in the VTA in vivo is aversive, and low-frequency stimulation induces long-term depression in vitro. Low-frequency stimulation of PAG afferents in vitro unexpectedly causes long-term potentiation. Opioid receptor activation profoundly depresses PAG and RMTg inhibitory synapses but prevents synaptic plasticity only at PAG synapses. Activation of the GABAergic PAG terminals in the VTA promotes immobility, and optogenetically-driven immobility is blocked by morphine. Our data reveal the PAG as a source of highly opioid-sensitive GABAergic afferents and support the idea that different GABAergic pathways to the VTA control distinct behaviors.
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Affiliation(s)
- Robyn St Laurent
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Valentina Martinez Damonte
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94035, USA
| | - Ayumi C Tsuda
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Julie A Kauer
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94035, USA.
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Simmons SJ, Gentile TA. Cocaine abuse and midbrain circuits: Functional anatomy of hypocretin/orexin transmission and therapeutic prospect. Brain Res 2020; 1731:146164. [PMID: 30796894 PMCID: PMC6702109 DOI: 10.1016/j.brainres.2019.02.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/09/2019] [Accepted: 02/12/2019] [Indexed: 12/18/2022]
Abstract
Cocaine abuse remains a pervasive public health problem, and treatments thus far have proven ineffective for long-term abstinence maintenance. Intensive research on the neurobiology underlying drug abuse has led to the consideration of many candidate transmitter systems to target for intervention. Among these, the hypocretin/orexin (hcrt/ox) neuropeptide system holds largely untapped yet clinically viable therapeutic potential. Hcrt/ox originates from the hypothalamus and projects widely across the mammalian central nervous system to produce neuroexcitatory actions via two excitatory G-protein coupled receptor subtypes. Functionally, hcrt/ox promotes arousal/wakefulness and facilitates energy homeostasis. In the early 2000s, hcrt/ox transmission was shown to underlie mating behavior in male rats suggesting a novel role in reward-seeking. Soon thereafter, hcrt/ox neurons were shown to respond to drug-associated stimuli, and hcrt/ox transmission was found to facilitate motivated responding for intravenous cocaine. Notably, blocking hcrt/ox transmission using systemic or site-directed pharmacological antagonists markedly reduced motivated drug-taking as well as drug-seeking in tests of relapse. This review will unfold the current state of knowledge implicating hcrt/ox receptor transmission in the context of cocaine abuse and provide detailed background on animal models and underlying midbrain circuits. Specifically, attention will be paid to the mesoaccumbens, tegmental, habenular, pallidal and preoptic circuits. The review will conclude with discussion of recent preclinical studies assessing utility of suvorexant - the first and only FDA-approved hcrt/ox receptor antagonist - against cocaine-associated behaviors.
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Affiliation(s)
- Steven J Simmons
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia Research Institute, Philadelphia, PA, USA; Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA.
| | - Taylor A Gentile
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, USA
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Karkhanis AN, Al-Hasani R. Dynorphin and its role in alcohol use disorder. Brain Res 2020; 1735:146742. [PMID: 32114059 DOI: 10.1016/j.brainres.2020.146742] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 02/04/2020] [Accepted: 02/25/2020] [Indexed: 02/07/2023]
Abstract
The dynorphin / kappa opioid receptor (KOR) system has been implicated in many aspects that influence neuropsychiatric disorders. Namely, this system modulates neural circuits that primarily regulate reward seeking, motivation processing, stress responsivity, and pain sensitivity, thus affecting the development of substance and alcohol use disorder (AUD). The effects of this system are often bidirectional and depend on projection targets. To date, a majority of the studies focusing on this system have examined the KOR function using agonists and antagonists. Indeed, there are studies that have examined prodynorphin and dynorphin levels by measuring mRNA and tissue content levels; however, static levels of the neuropeptide and its precursor do not explain complete and online function of the peptide as would be explained by measuring dynorphin transmission in real time. New and exciting methods using optogenetics, chemogenetics, genetic sensors, fast scan cyclic voltammetry are now being developed to detect various neuropeptides with a focus on opioid peptides, including dynorphin. In this review we discuss studies that examine dynorphin projections in areas involved in AUD, its functional involvement in AUD and vulnerability to develop AUD at various ages. Moreover, we discuss dynorphin's role in promoting AUD by dysregulation motivation circuits and how advancements in opioid peptide detection will further our understanding.
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Affiliation(s)
- Anushree N Karkhanis
- Department of Psychology, Developmental Exposure Alcohol Research Center, Center for Developmental and Behavioral Neuroscience, Binghamton University - SUNY, 4400 Vestal Parkway East, Binghamton, NY 13902, USA.
| | - Ream Al-Hasani
- Department of Pharmaceutical and Administrative Sciences, St. Louis College of Pharmacy, Department of Anesthesiology Washington University in St. Louis, Center for Clinical Pharmacology, Washington University School of Medicine & St. Louis College of Pharmacy 660 S.Euclid, Box 8054, St. Louis, MO 63110, USA.
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Robble MA, Bozsik ME, Wheeler DS, Wheeler RA. Learned avoidance requires VTA KOR-mediated reductions in dopamine. Neuropharmacology 2020; 167:107996. [PMID: 32057802 DOI: 10.1016/j.neuropharm.2020.107996] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 01/03/2020] [Accepted: 02/08/2020] [Indexed: 12/31/2022]
Abstract
Proper learning from an aversive experience is essential for survival, yet it is an aberrant process in a wide range of mental disorders, as well as dopaminergic neurodegenerative disease. While the mesolimbic dopamine system is known to be essential for reward learning, the characterization of a potential pattern of dopamine signaling that guides avoidance remains unknown. Aversive stimuli may directly modulate dopamine signaling through the dynorphin/kappa opioid receptor (KOR) system, as kappa opioid receptors are expressed in this neural circuit and their activation is aversive in both rodents and humans. Ventral tegmental area (VTA) KORs are ideally positioned to directly shape aversion-induced reductions in dopamine signaling, but their role in this process has received little consideration. To determine the necessity of VTA KOR activity in the regulation of dopamine signaling and avoidance, we tested the effects of VTA KOR blockade on real time dopaminergic responses to aversive stimuli and learned avoidance in male Sprague-Dawley rats. We found that blockade of VTA KORs attenuated aversion-induced reductions in dopamine, and this treatment also prevented avoidance following the aversive experience. To determine whether aversion-induced reductions in striatal dopamine are necessary for avoidance, we tested avoidance following treatment with an intra nucleus accumbens D2 receptor agonist. This treatment also prevented avoidance and is consistent with the view that aversion-induced reductions in dopamine reduce dopamine signaling at high affinity D2 receptors and disinhibit an aversion-sensitive striatal output circuit to promote avoidance.
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Affiliation(s)
- Mykel A Robble
- Dept. Biomedical Sciences, Marquette University, 561 N. 15th St SC 446, Milwaukee, WI, 53233, USA.
| | - Mary E Bozsik
- Dept. Biomedical Sciences, Marquette University, 561 N. 15th St SC 446, Milwaukee, WI, 53233, USA
| | - Daniel S Wheeler
- Dept. Biomedical Sciences, Marquette University, 561 N. 15th St SC 446, Milwaukee, WI, 53233, USA.
| | - Robert A Wheeler
- Dept. Biomedical Sciences, Marquette University, 561 N. 15th St SC 446, Milwaukee, WI, 53233, USA.
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