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Medrano M, Allaoui W, Haddad RES, Makrini-Maleville L, Valjent E, Smolders I, Kormos V, Gaszner B, De Bundel D. Neuromedin U Neurons in the Edinger-Westphal Nucleus Respond to Alcohol Without Interfering with the Urocortin 1 Response. Neurochem Res 2024:10.1007/s11064-024-04238-1. [PMID: 39266897 DOI: 10.1007/s11064-024-04238-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2024] [Revised: 08/29/2024] [Accepted: 09/03/2024] [Indexed: 09/14/2024]
Abstract
The Edinger-Westphal nucleus (EW) is a midbrain nucleus composed of a preganglionic, cholinergic subpopulation and a densely clustered peptidergic subpopulation (EWcp). The EWcp is one of the few brain regions that show consistent induction of FOS following voluntary alcohol intake. Previous results in rodents point to urocortin 1 (UCN1) as one of the peptides most involved in the control of ethanol intake and preference. Notably, the functions described for UCN1, such as reward processing, stress coping or the regulation of feeding behavior are similar to those described for the neuropeptide neuromedin U (NMU). Interestingly, NMU has been recently associated with the modulation of alcohol-related behaviors. However, little is known about the expression and functionality of NMU neurons in alcohol-responsive areas. In this study, we used the recently developed Nmu-Cre knock-in mouse model to examine the expression of NMU in the subaqueductal paramedian zone comprising the EWcp. We delved into the characterization and co-expression of NMU with other markers already described in the EWcp. Moreover, using FOS as a marker of neuronal activity, we tested whether NMU neurons were sensitive to acute alcohol administration. Overall, we provided novel insights on NMU expression and functionality in the EW region. We showed the presence of NMU within a subpopulation of UCN1 neurons in the EWcp and demonstrated that this partial co-expression does not interfere with the responsivity of UCN1-containing cells to alcohol. Moreover, we proposed that the UCN1 content in these neurons may be influenced by sex.
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Affiliation(s)
- Mireia Medrano
- Center for Neurosciences, Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Wissal Allaoui
- Center for Neurosciences, Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Ra'fat Ehab Salim Haddad
- Medical School, Research Group for Mood Disorders, Department of Anatomy and Centre for Neuroscience, University of Pécs, Szigeti út 12, 7624, Pécs, Hungary
| | | | - Emmanuel Valjent
- IGF, Université de Montpellier, CNRS, Inserm, Montpellier, France
| | - Ilse Smolders
- Center for Neurosciences, Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Viktória Kormos
- Medical School, Department of Pharmacology and Pharmacotherapy, University of Pécs, Szigeti út 12, 7624, Pécs, Hungary
| | - Balázs Gaszner
- Medical School, Research Group for Mood Disorders, Department of Anatomy and Centre for Neuroscience, University of Pécs, Szigeti út 12, 7624, Pécs, Hungary.
| | - Dimitri De Bundel
- Center for Neurosciences, Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Research Group Experimental Pharmacology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium.
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2
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Kasper JM, Smith AE, Miller SN, Ara, Russell WK, Cunningham KA, Hommel JD. Role of neuropeptide neuromedin U in the nucleus accumbens shell in cocaine self-administration in male rats. Neuropsychopharmacology 2022; 47:1875-1882. [PMID: 34916591 PMCID: PMC9485260 DOI: 10.1038/s41386-021-01234-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 10/29/2021] [Accepted: 11/03/2021] [Indexed: 11/09/2022]
Abstract
The nucleus accumbens shell (NAcSh) and its afferent and efferent neuronal projections control key aspects of motivation for cocaine. A recently described regulator of γ-aminobutyric acid (GABA) projections from the dorsal raphe nucleus (DRN) to the NAcSh (DRN → NAcSh) is the neuropeptide neuromedin U (NMU). Here, we find that systemic administration of NMU decreases breakpoint for cocaine on a progressive ratio schedule of reinforcement in male rats. Employing a retrograde adeno-associated virus (AAV), we found that RNAi-mediated knockdown of the NMU receptor 2 (NMUR2) in afferent DRN projections to the NAcSh increases the breakpoint for cocaine. Our previous studies demonstrated that NMU regulates GABA release in the NAcSh, and our current investigation found that systemic NMU administration suppresses cocaine-evoked GABA release in the NAcSh and increases phosphorylated c-Fos expression in neurons projecting from the NAcSh to the ventral pallidum (VP). To further probe the impact of NMU/NMUR2 on neuroanatomical pathways regulating motivation for cocaine, we employed multi-viral transsynaptic studies. Using a combination of rabies virus and retrograde AAV helper virus, we mapped the impact of NMU across three distinct brain regions simultaneously and found a direct connection of GABAergic DRN neurons to the NAcSh → VP pathway. Together, these data reveal that NMU/NMUR2 modulates a direct connection within the GABAergic DRN → NAcSh → VP circuit that diminishes breakpoints for cocaine. These findings importantly advance our understanding of the neurochemical underpinnings of pathway-specific regulation of neurocircuitry that may regulate cocaine self-administration, providing a unique therapeutic perspective.
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Affiliation(s)
- James M Kasper
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Ashley E Smith
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Sierra N Miller
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Ara
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - William K Russell
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Kathryn A Cunningham
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, 77555, USA.
| | - Jonathan D Hommel
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, 77555, USA.
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Gholami Ahmadabadi K, Zendehdel M, Vazir B, Asghari A, Babapour V. Possible effects of the central adrenergic and dopaminergic receptors on hypophagia induced by neuromedin S in neonatal layer-type chicks. Gen Comp Endocrinol 2022; 321-322:114032. [PMID: 35331741 DOI: 10.1016/j.ygcen.2022.114032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 02/13/2022] [Accepted: 03/19/2022] [Indexed: 11/30/2022]
Abstract
The current study was aimed to determine the possible effects of the central adrenergic and dopaminergic receptors in neuromedin S (NMS)-induced hypophagia in neonatal layer-type chickens. In the first experiment, control solution, and NMS (0.25, 0.5, and 1 nmol), were injected (intracerebroventricular (ICV)) in chickens. In the second experiment, birds were injected with a control solution,SCH23390 (D1receptor antagonist, 5 nmol), NMS (1 nmol), and a combination of the SCH23390 + NMS. Experiments 3-11 were similar to experiment 2, except that chickens were injected withAMI-193 (D2receptor antagonist, 5 nmol), NGB2904(D3receptor antagonist, 6.4 nmol), L-741,742(D4receptor antagonist, 6 nmol), 6-OHDA(6-hydroxydopamine, 2.5 nmol),Prazosin(α1receptor antagonist, 10 nmol),Yohimbine(α2receptor antagonist, 13 nmol),Metoprolol(β1receptor antagonist receptor, 24 nmol),ICI 118,551 (β2receptor antagonist, 5 nmol),SR 59230R (β3 receptor antagonist, 20 nmol) instead ofSCH23390. Then, cumulative food intake was recorded at 30, 60, and 120 min following the injection. According to the results, food intake was significantly decreased after ICV injection of NMS in a dose -dependent manner (P < 0.05). Also, the co-injection of the SCH23390 + NMS significantly attenuated NMS-induced hypophagia (P < 0.05). The co-administration of AMI-193 + NMS significantly reduced NMS- induced hypophagia (P < 0.05). In addition, the co-injection of ICI 118,551 + NMS and 6-OHDA + NMS considerably decreased NMS-induced food consumption (P < 0.05). However, NGB2904, L-741742, Prazosin, Yohimbine, Metoprolol and SR 59230R had no effect on hypophagia induced by NMS (P > 0.05). These results demonstrated thatNMS- induced hypophagia might be mediated by D1/D2 dopaminergic andβ2adrenergic receptors in neonatal layer-type chickens.
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Affiliation(s)
- Kourosh Gholami Ahmadabadi
- Department of Basic Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Morteza Zendehdel
- Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tehran, 14155-6453 Tehran, Iran.
| | - Bita Vazir
- Department of Basic Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Ahamd Asghari
- Department of Clinical Science, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Vahab Babapour
- Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tehran, 14155-6453 Tehran, Iran
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Neuromedin U, a Key Molecule in Metabolic Disorders. Int J Mol Sci 2021; 22:ijms22084238. [PMID: 33921859 PMCID: PMC8074168 DOI: 10.3390/ijms22084238] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 12/25/2022] Open
Abstract
Obesity is now a public health concern. The leading cause of obesity is an energy imbalance between ingested and expended calories. The mechanisms of feeding behavior and energy metabolism are regulated by a complex of various kinds of molecules, including anorexigenic and orexigenic neuropeptides. One of these neuropeptides, neuromedin U (NMU), was isolated in the 1980s, and its specific receptors, NMUR1 and NMUR2, were defined in 2000. A series of subsequent studies has revealed many of the physiological roles of the NMU system, including in feeding behavior, energy expenditure, stress responses, circadian rhythmicity, and inflammation. Particularly over the past decades, many reports have indicated that the NMU system plays an essential and direct role in regulating body weight, feeding behavior, energy metabolism, and insulin secretion, which are tightly linked to obesity pathophysiology. Furthermore, another ligand of NMU receptors, NMS (neuromedin S), was identified in 2005. NMS has physiological functions similar to those of NMU. This review summarizes recent observations of the NMU system in relation to the pathophysiology of obesity in both the central nervous systems and the peripheral tissues.
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Anan M, Higa R, Shikano K, Shide M, Soda A, Carrasco Apolinario ME, Mori K, Shin T, Miyazato M, Mimata H, Hikida T, Hanada T, Nakao K, Kangawa K, Hanada R. Cocaine has some effect on neuromedin U expressing neurons related to the brain reward system. Heliyon 2020; 6:e03947. [PMID: 32462086 PMCID: PMC7240118 DOI: 10.1016/j.heliyon.2020.e03947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 12/20/2019] [Accepted: 05/05/2020] [Indexed: 02/07/2023] Open
Abstract
Neuromedin U (NMU) is a bioactive neuropeptide, highly distributed in the gastrointestinal tract and the central nervous system. NMU has various physiological functions related to feeding behavior, energy metabolism, stress responses, circadian rhythmicity and inflammation. Recently, several reports indicate that the central NMU system plays an important role in the reward systems in the brain. However, the underlying molecular mechanisms are not yet fully defined. In this study, we found that some of cocaine-induced c-Fos immunoreactive cells were co-localized with NMU in the nucleus accumbens (NAc), caudate putamen (CPu), and basolateral amygdala (BLA), which are key brain regions associated with the brain reward system, in wild type mice. Whereas, a treatment with cocaine did not influence the kinetics of NMU or NMU receptors mRNA expression in these brain regions, and NMU-knockout mice did not show any higher preference for cocaine compared with their control mice. These results indicate that cocaine has some effect on NMU expressing neurons related to the brain reward system, and this suggests NMU system may have a role on the brain reward systems activated by cocaine.
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Affiliation(s)
- Madoka Anan
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | - Ryoko Higa
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | - Kenshiro Shikano
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | - Masahito Shide
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | - Akinobu Soda
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
| | | | - Kenji Mori
- Department of Biochemistry, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Toshitaka Shin
- Department of Urology, Faculty of Medicine, Oita University, Oita, Japan
| | - Mikiya Miyazato
- Department of Biochemistry, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Hiromitsu Mimata
- Department of Urology, Faculty of Medicine, Oita University, Oita, Japan
| | - Takatoshi Hikida
- Laboratory for Advanced Brain Functions, Institute for Protein Research, Osaka University, Osaka, Japan
| | - Toshikatsu Hanada
- Department of Cell Biology, Faculty of Medicine, Oita University, Oita, Japan
| | - Kazuwa Nakao
- Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kenji Kangawa
- Department of Biochemistry, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan
| | - Reiko Hanada
- Department of Neurophysiology, Faculty of Medicine, Oita University, Oita, Japan
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Vallöf D, Kalafateli AL, Jerlhag E. Brain region-specific neuromedin U signalling regulates alcohol-related behaviours and food intake in rodents. Addict Biol 2020; 25:e12764. [PMID: 31069918 PMCID: PMC7187236 DOI: 10.1111/adb.12764] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 12/21/2022]
Abstract
Albeit neuromedin U (NMU) attenuates alcohol‐mediated behaviours, its mechanisms of action are poorly defined. Providing that the behavioural effects of alcohol are processed within the nucleus accumbens (NAc) shell, anterior ventral tegmental area (aVTA), and laterodorsal tegmental area (LDTg), we assessed the involvement of NMU signalling in the aforementioned areas on alcohol‐mediated behaviours in rodents. We further examined the expression of NMU and NMU receptor 2 (NMUR2) in NAc and the dorsal striatum of high compared with low alcohol‐consuming rats, as this area is of importance in the maintenance of alcohol use disorder (AUD). Finally, we investigated the involvement of NAc shell, aVTA and LDTg in the consumption of chow and palatable peanut butter, to expand the link between NMU and reward‐related behaviours. We demonstrated here, that NMU into the NAc shell, but not aVTA or LDTg, blocked the ability of acute alcohol to cause locomotor stimulation and to induce memory retrieval of alcohol reward, as well as reduced peanut butter in mice. In addition, NMU into NAc shell decreased alcohol intake in rats. On a molecular level, we found increased NMU and decreased NMUR2 expression in the dorsal striatum in high compared with low alcohol‐consuming rats. Both aVTA and LDTg, rather than NAc shell, were identified as novel sites of action for NMU's anorexigenic properties in mice based on NMU's ability to selectively reduce chow intake when injected to these areas. Collectively, these data indicate that NMU signalling in different brain areas selectively modulates different behaviours.
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Affiliation(s)
- Daniel Vallöf
- Institute of Neuroscience and Physiology, Department of PharmacologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Aimilia Lydia Kalafateli
- Institute of Neuroscience and Physiology, Department of PharmacologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of PharmacologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
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De Prins A, Allaoui W, Medrano M, Van Eeckhaut A, Ballet S, Smolders I, De Bundel D. Effects of neuromedin U-8 on stress responsiveness and hypothalamus-pituitary-adrenal axis activity in male C57BL/6J mice. Horm Behav 2020; 121:104666. [PMID: 31899262 DOI: 10.1016/j.yhbeh.2019.104666] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/29/2019] [Accepted: 12/24/2019] [Indexed: 01/31/2023]
Abstract
Neuromedin U (NMU) is a highly conserved neuropeptide that has been implicated in the stress response. To better understand how it influences various aspects of the stress response, we studied the effects of intracerebroventricular NMU-8 administration on stress-related behavior and activity of the hypothalamus-pituitary-adrenal (HPA) axis in male C57BL/6J mice. We investigated these NMU-8 effects when mice remained in their home cage and when they were challenged by exposure to forced swim stress. NMU-8 administration resulted in increased grooming behavior in mice that remained in their home cage and in a significant increase in c-Fos immunoreactivity in the paraventricular hypothalamus (PVH) and arcuate nucleus (ARC). Surprisingly, NMU-8 administration significantly decreased plasma corticosterone concentrations. Furthermore, NMU-8 administration increased immobility in the forced swim test in both naïve mice and mice that were previously exposed to swim stress. The effect of NMU-8 on c-Fos immunoreactivity in the PVH was dependent on previous exposure to swim stress given that we observed no significant changes in mice exposed for the first time to swim stress. In contrast, in the ARC we observed a significant increase in c-Fos immunoreactivity regardless of previous stress exposure. Interestingly, NMU-8 administration also significantly decreased plasma corticosterone concentrations in mice that were exposed to single forced swim stress, while this effect was no longer observed when mice were exposed to forced swim stress for a second time. Taken together, our data indicate that NMU-8 regulates stress responsiveness and suggests that its effects depend on previous stress exposure.
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Affiliation(s)
- An De Prins
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Wissal Allaoui
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Mireia Medrano
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Ann Van Eeckhaut
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Steven Ballet
- Research Group of Organic Chemistry, Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Ilse Smolders
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Dimitri De Bundel
- Department of Pharmaceutical Chemistry, Drug Analysis and Drug Information, Center for Neurosciences (C4N), Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium.
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Ulenius L, Adermark L, Söderpalm B, Ericson M. Energy drink constituents (caffeine and taurine) selectively potentiate ethanol-induced locomotion in mice. Pharmacol Biochem Behav 2019; 187:172795. [PMID: 31669834 DOI: 10.1016/j.pbb.2019.172795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/29/2019] [Accepted: 10/02/2019] [Indexed: 02/06/2023]
Abstract
Mixing alcohol with energy drinks has emerged as a popular trend over the last decade. However, epidemiological studies have found this consumption to be associated with increased hazards, such as binge drinking, increased alcohol-related harm and risk of developing alcohol use disorder. The mechanisms underlying these effects are not clear, but much attention has been attributed to caffeine. However, taurine, another common ingredient in energy drinks, has also been associated with the dopamine elevating properties of ethanol, and may in this respect contribute to the increased liability associated with the mixture of alcohol and energy drinks. In the present study we measured locomotor activity, a phenomenon previously linked to the dopamine activating and reinforcing properties of the drug, following acute systemic administration with caffeine (1, 5, 15, 30 mg/kg), taurine (30, 60, 300, 600 mg/kg) and ethanol (1.75, 2.5, 3.25 g/kg), alone or in combination. We found that ethanol and caffeine, but not taurine, increased locomotion compared to vehicle. In addition, when combined with ethanol, caffeine, but not taurine, increased the locomotor stimulatory effect of ethanol. Furthermore, the combination of caffeine and taurine were able to further enhance the ethanol-induced locomotor response. Eleven days of intermittent caffeine exposure produced a sensitized response to the caffeine-induced locomotion, but did not alter the additive effect produced by the combination of caffeine and taurine on ethanol-induced locomotion. Based on the present study we suggest that the combination of caffeine and taurine, at a specific dose range, enhances the locomotor stimulatory properties of ethanol, a phenomenon previously linked to the reinforcing properties of the drug.
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Affiliation(s)
- Lisa Ulenius
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, PO Box 410, 405 30 Gothenburg, Sweden.
| | - Louise Adermark
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, PO Box 410, 405 30 Gothenburg, Sweden
| | - Bo Söderpalm
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, PO Box 410, 405 30 Gothenburg, Sweden; Beroendekliniken, Sahlgrenska University Hospital, Blå Stråket 15, 413 45 Gothenburg, Sweden
| | - Mia Ericson
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, PO Box 410, 405 30 Gothenburg, Sweden
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9
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Vestlund J, Kalafateli AL, Studer E, Westberg L, Jerlhag E. Neuromedin U induces self-grooming in socially-stimulated mice. Neuropharmacology 2019; 162:107818. [PMID: 31647973 DOI: 10.1016/j.neuropharm.2019.107818] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 09/17/2019] [Accepted: 10/18/2019] [Indexed: 11/19/2022]
Abstract
Emerging evidence suggest that appetite-regulating peptides modulate social behaviors. We here investigate whether the anorexigenic peptide neuromedin U (NMU) modulates sexual behavior in male mice. However, instead of modulating sexual behaviors, NMU administered into the third ventricle increased self-grooming behavior. In addition, NMU-treatment increased self-grooming behavior when exposed to other mice or olfactory social-cues, but not when exposed to non-social environments. As the neuropeptide oxytocin is released during social investigation and exogenous oxytocin induces self-grooming, its role in NMU-induced self-grooming behavior was investigated. In line with our hypothesis, the oxytocin receptor antagonist inhibited NMU-induced self-grooming behavior in mice exposed to olfactory social-cues. Moreover, dopamine in the mesocorticolimbic system is known to be a key regulator of self-grooming behavior. In line with this, we proved that infusion of NMU into nucleus accumbens increased self-grooming behavior in mice confronted with an olfactory social-cue and that this behavior was inhibited by antagonism of dopamine D2, but not D1/D5, receptors. Moreover repeated NMU treatment enhanced ex vivo dopamine levels and decreased the expression of dopamine D2 receptors in nucleus accumbens in socially housed mice. On the other hand, the olfactory stimuli-dependent NMU-induced self-grooming was not affected by a corticotrophin-releasing hormone antagonist, and NMU-treatment did not influence repetitive behaviors in the marble burying test. In conclusion, our results suggest that NMU treatment and, social cues - potentially triggering oxytocin release - together induce excessive grooming behavior in male mice. The mesolimbic dopamine system, including accumbal dopamine D2 receptors, was identified as a crucial downstream mechanism.
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Affiliation(s)
- Jesper Vestlund
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Aimilia Lydia Kalafateli
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Erik Studer
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Lars Westberg
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
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10
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Kalafateli AL, Vallöf D, Jerlhag E. Activation of amylin receptors attenuates alcohol-mediated behaviours in rodents. Addict Biol 2019; 24:388-402. [PMID: 29405517 PMCID: PMC6585842 DOI: 10.1111/adb.12603] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/14/2017] [Accepted: 01/05/2018] [Indexed: 02/06/2023]
Abstract
Alcohol expresses its reinforcing properties by activating areas of the mesolimbic dopamine system, which consists of dopaminergic neurons projecting from the ventral tegmental area to the nucleus accumbens. The findings that reward induced by food and addictive drugs involve common mechanisms raise the possibility that gut-brain hormones, which control appetite, such as amylin, could be involved in reward regulation. Amylin decreases food intake, and despite its implication in the regulation of natural rewards, tenuous evidence support amylinergic mediation of artificial rewards, such as alcohol. Therefore, the present experiments were designed to investigate the effect of salmon calcitonin (sCT), an amylin receptor agonist and analogue of endogenous amylin, on various alcohol-related behaviours in rodents. We showed that acute sCT administration attenuated the established effects of alcohol on the mesolimbic dopamine system, particularly alcohol-induced locomotor stimulation and accumbal dopamine release. Using the conditioned place preference model, we demonstrated that repeated sCT administration prevented the expression of alcohol's rewarding properties and that acute sCT administration blocked the reward-dependent memory consolidation. In addition, sCT pre-treatment attenuated alcohol intake in low alcohol-consuming rats, with a more evident decrease in high alcohol consumers in the intermittent alcohol access model. Lastly, sCT did not alter peanut butter intake, blood alcohol concentration and plasma corticosterone levels in mice. Taken together, the present data support that amylin signalling is involved in the expression of alcohol reinforcement and that amylin receptor agonists could be considered for the treatment of alcohol use disorder in humans.
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Affiliation(s)
- Aimilia Lydia Kalafateli
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Daniel Vallöf
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of Gothenburg Gothenburg Sweden
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Millón C, Flores-Burgess A, Castilla-Ortega E, Gago B, García-Fernandez M, Serrano A, Rodriguez de Fonseca F, Narváez JA, Fuxe K, Santín L, Díaz-Cabiale Z. Central administration of galanin N-terminal fragment 1-15 decreases the voluntary alcohol intake in rats. Addict Biol 2019; 24:76-87. [PMID: 29210146 DOI: 10.1111/adb.12582] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 09/27/2017] [Accepted: 10/27/2017] [Indexed: 11/28/2022]
Abstract
Alcohol consumption is considered a major risk factor for disease and mortality worldwide. In the absence of effective treatments in alcohol use disorders, it is important to find new biological targets that could modulate alcohol consumption. We tested the role of the N-terminal galanin fragment (1-15) [GAL(1-15)] in voluntary ethanol consumption in rats using the two-bottle choice paradigm as well as compare the effects of GAL(1-15) with the whole molecule of GAL. We describe for the first time that GAL(1-15), via central mechanisms, induces a strong reduction in preference and ethanol consumption in rats. These effects were significantly different than GAL. GAL receptor (GALR) 2 was involved in these effects, because the specific GALR2 antagonist M871 blocked GAL(1-15) mediated actions in preference and ethanol intake. Importantly, the mechanism of this action involves changes in GALR expression and also in immediate-early gene C-Fos and receptors-internalization-related gene Rab5 in the striatum. The relevance of the striatum as a target for GAL(1-15) was supported by the effect of GAL(1-15) on the locomotor activity of rats after ethanol administration. These results may give the basis for the development of novel therapeutics strategies using GAL(1-15) analogues for the treatment of alcohol use disorders in humans.
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Affiliation(s)
- Carmelo Millón
- Facultad de Medicina, Instituto de Investigación Biomédica de Málaga; Universidad de Málaga; Spain
| | - Antonio Flores-Burgess
- Facultad de Medicina, Instituto de Investigación Biomédica de Málaga; Universidad de Málaga; Spain
| | - Estela Castilla-Ortega
- Unidad de Gestión Clínica de Salud Mental e Instituto de Investigación Biomédica de Málaga; Hospital Regional Universitario de Málaga; Spain
| | - Belén Gago
- Facultad de Medicina, Instituto de Investigación Biomédica de Málaga; Universidad de Málaga; Spain
| | - María García-Fernandez
- Facultad de Medicina, Instituto de Investigación Biomédica de Málaga; Universidad de Málaga; Spain
| | - Antonia Serrano
- Unidad de Gestión Clínica de Salud Mental e Instituto de Investigación Biomédica de Málaga; Hospital Regional Universitario de Málaga; Spain
| | - Fernando Rodriguez de Fonseca
- Unidad de Gestión Clínica de Salud Mental e Instituto de Investigación Biomédica de Málaga; Hospital Regional Universitario de Málaga; Spain
| | - José Angel Narváez
- Facultad de Medicina, Instituto de Investigación Biomédica de Málaga; Universidad de Málaga; Spain
| | - Kjell Fuxe
- Department of Neuroscience; Karolinska Institute; Sweden
| | - Luis Santín
- Instituto de Investigación Biomédica de Málaga, Facultad de Psicología; Universidad de Málaga; Spain
| | - Zaida Díaz-Cabiale
- Facultad de Medicina, Instituto de Investigación Biomédica de Málaga; Universidad de Málaga; Spain
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12
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Kasper JM, Smith AE, Hommel JD. Cocaine-Evoked Locomotor Activity Negatively Correlates With the Expression of Neuromedin U Receptor 2 in the Nucleus Accumbens. Front Behav Neurosci 2018; 12:271. [PMID: 30483076 PMCID: PMC6243026 DOI: 10.3389/fnbeh.2018.00271] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 10/22/2018] [Indexed: 11/24/2022] Open
Abstract
Cocaine use disorder (CUD) is characterized by repeated cycles of drug seeking and drug taking. Currently, there are no available pharmacotherapies to treat CUD, partially due to a lack of a mechanistic understanding of cocaine-evoked alterations in the brain that drive drug-related behaviors. Repeated cocaine use alters expression of numerous genes in addiction-associated areas of the brain and these alterations are in part driven by inter-subject genetic variability. Recent findings have shown the neuropeptide neuromedin U (NMU) and its receptor NMU receptor 2 (NMUR2) decrease drug-related behaviors, but it is unknown if substances of abuse alter NMU or NMUR2 expression. Here, rats were given twice daily saline or cocaine (15 mg/kg, intraperitoneal (IP)) for 5 days and then 7 days with no treatment. All rats were then given a single cocaine treatment and locomotor activity was measured in the acute (non-sensitized) and repeated drug exposure (sensitized) groups. Immediately following locomotor assay, tissue was taken and we demonstrate that accumbal NMUR2 mRNA expression, but not NMU mRNA expression, is negatively correlated with non-sensitized cocaine-evoked locomotor activity, but the correlation is lost following cocaine sensitization. Furthermore, in a separate cohort NMUR2 protein levels also negatively correlated with cocaine-evoked locomotor activity based on immunohistochemical stereology for NMUR2 protein expression. These findings are the first to demonstrate that repeated cocaine exposure causes dysregulated expression of NMUR2 and highlight the deleterious effects of repeated cocaine exposure on neurobiological receptor systems. Restoring the normal function of NMUR2 could be beneficial to the treatment of CUD.
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Affiliation(s)
- James M Kasper
- Center for Addiction Research, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Ashley E Smith
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX, United States
| | - Jonathan D Hommel
- Center for Addiction Research, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
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13
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Huang H, Zhang X, Fu X, Zhang X, Lang B, Xiang X, Hao W. Alcohol-induced conditioned place preference negatively correlates with anxiety-like behavior in adolescent mice: inhibition by a neurokinin-1 receptor antagonist. Psychopharmacology (Berl) 2018; 235:2847-2857. [PMID: 30054674 DOI: 10.1007/s00213-018-4976-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 07/17/2018] [Indexed: 01/23/2023]
Abstract
RATIONALE Although alcohol use disorder and anxiety disorders are highly comorbid in humans, controversy remains regarding whether anxiety predisposes individuals to alcohol reward, and the relationship with neurokinin-1 receptor (NK1R) is unclear. OBJECTIVES The objectives of the study are to investigate the association between anxiety-like behavior and alcohol-induced conditioned place preference (CPP) and to examine the effect of NK1R antagonist L-703,606 on this preference and levels of NK1R protein in different brain regions in adolescent mice. METHODS The anxiety-like behavior of adolescent male C57BL/6 mice was assessed using the elevated plus maze (EPM) test, and the animals were then allocated into high-anxiety mouse (HAM) and low-anxiety mouse (LAM) groups based on the percent of open arm time (OT%). After the reinforcement of ethanol was established by alcohol-induced CPP (2 g/kg), NK1R expression was quantified in the hippocampus, prefrontal cortex, and amygdala. Finally, the effect of L-703,606 (10 mg/kg) on the alcohol-induced CPP was examined. RESULTS LAM showed a greater ethanol preference (P = 0.004) and a higher level of NK1R protein in the hippocampus (P = 0.026) than HAM group. Interestingly, the CPP score positively correlated with OT% (r = 0.520, P = 0.016) and the level of NK1R protein (r = 0.476, P = 0.029) in the hippocampus. Moreover, L-703,606 attenuated alcohol-induced CPP (P < 0.001) in both groups. CONCLUSIONS The present results highlight the negative correlation between anxiety-like behavior and the propensity for alcohol and the critical role for NK1R in alcohol reward in adolescent mice. Importantly, the NK1R antagonist L-703,606 might be a promising therapeutic target for alcohol use disorder.
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Affiliation(s)
- Hui Huang
- Mental Health Institute of the Second Xiangya Hospital, The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, People's Republic of China.,Department of Psychiatry, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People's Republic of China
| | - Xiaojie Zhang
- Mental Health Institute of the Second Xiangya Hospital, The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, People's Republic of China
| | - Xiaoya Fu
- Mental Health Institute of the Second Xiangya Hospital, The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, People's Republic of China
| | - Xiangyang Zhang
- Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Bing Lang
- Mental Health Institute of the Second Xiangya Hospital, The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, People's Republic of China
| | - Xiaojun Xiang
- Mental Health Institute of the Second Xiangya Hospital, The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, People's Republic of China.
| | - Wei Hao
- Mental Health Institute of the Second Xiangya Hospital, The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, People's Republic of China.
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14
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Vallöf D, Ulenius L, Egecioglu E, Engel JA, Jerlhag E. Central administration of the anorexigenic peptide neuromedin U decreases alcohol intake and attenuates alcohol-induced reward in rodents. Addict Biol 2017; 22:640-651. [PMID: 26769653 PMCID: PMC6680249 DOI: 10.1111/adb.12355] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 10/26/2015] [Accepted: 12/01/2015] [Indexed: 01/24/2023]
Abstract
By investigating the neurochemical mechanisms through which alcohol activates the brain reward systems, novel treatment strategies for alcohol use disorder (AUD), a chronic relapsing disease, can be developed. In contrast to the common view of the function of gut-brain peptides, such as neuromedin U (NMU), to regulate food intake and appetite, a novel role in reinforcement mediation has been implied. The anorexigenic effects of NMU are mediated via NMU2 receptors, preferably in the arcuate nucleus and paraventricular nucleus. The expression of NMU2 receptors is also expressed in several reward-related areas in the brain, suggesting a role in reward regulation. The present experiments were therefore set up to investigate the effect of intracerebroventricular administration of NMU on alcohol-mediated behaviors in rodents. We found that central administration of NMU attenuated alcohol-induced locomotor stimulation, accumbal dopamine release and the expression of conditioned place preference in mice. In addition, NMU dose dependently decreased alcohol intake in high, but not in low, alcohol-consuming rats. Central NMU administration did not alter the blood alcohol concentrations nor change the corticosterone levels in rodents. Given that AUD is a major health-care challenge causing an enormous cost to society and novel treatment strategies are warranted, our data suggest that NMU analogues deserve to be evaluated as novel treatment of AUD in humans.
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Affiliation(s)
- Daniel Vallöf
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Lisa Ulenius
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Emil Egecioglu
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Jörgen A. Engel
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
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15
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Yang BZ, Han S, Kranzler HR, Palmer AA, Gelernter J. Sex-specific linkage scans in opioid dependence. Am J Med Genet B Neuropsychiatr Genet 2017; 174:261-268. [PMID: 27762075 PMCID: PMC5695218 DOI: 10.1002/ajmg.b.32507] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 10/03/2016] [Indexed: 02/01/2023]
Abstract
Sex influences risk for opioid dependence (OD). We hypothesized that sex might interact with genetic loci that influence the risk for OD. Therefore we performed an analysis to identify sex-specific genomic susceptibility regions for OD using linkage. Over 6,000 single nucleotide polymorphism (SNP) markers were genotyped for 1,758 African- and European-American (AA and EA) individuals from 739 families, ascertained via affected sib-pairs with OD and/or cocaine dependence. Autosomewide non-parametric linkage scans, stratified by sex and population, were performed. We identified one significant linkage region, segregating with OD in EA men, at 71.1 cM on chromosome 4 (LOD = 3.29; point-wise P = 0.00005; empirical autosome-wide P = 0.042), which significantly differed from the linkage signal at the same location in EA women (empirical P = 0.002). Three suggestive linkage signals were identified at 181.3 cM on chromosome 7 (LOD = 2.18), 104 cM on chromosome 11 (LOD = 1.85), and 60.9 cM on chromosome 16 (LOD = 1.93) in EA women. In AA men, four suggestive linkage signals were detected at 201.1 cM on chromosome 3 (LOD = 2.32), 152.9 cM on chromosome 6 (LOD = 1.86), 16.8 cM on chromosome 7 (LOD = 1.95), and 36.1 cM on chromosome 17 (LOD = 1.99). The significant region, mapping to 4q12-4q13.1, harbors several OD candidate genes with interconnected functionality, including VEGFR, CLOCK, PDCL2, NMU, NRSF, and IGFBP7. In conclusion, these results provide an evidence for the existence of sex-specific and population-specific differences in OD. Furthermore, these results provide positional information that will facilitate the use of targeted next-generation sequencing to search for genes that contribute to sex-specific differences in OD. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Bao-Zhu Yang
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT
| | - Shizhong Han
- Department of Psychiatry, University of Iowa, Iowa City, IA
| | - Henry R. Kranzler
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine and VISN 4 MIRECC, Crescenz VAMC, Philadelphia, PA
| | - Abraham A. Palmer
- Department of Psychiatry, University of California San Diego, La Jolla, CA
| | - Joel Gelernter
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT,VA CT Healthcare Center, West Haven, CT
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16
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McCue DL, Kasper JM, Hommel JD. Regulation of motivation for food by neuromedin U in the paraventricular nucleus and the dorsal raphe nucleus. Int J Obes (Lond) 2017; 41:120-128. [PMID: 27748746 PMCID: PMC5209284 DOI: 10.1038/ijo.2016.178] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 09/02/2016] [Accepted: 09/13/2016] [Indexed: 12/02/2022]
Abstract
BACKGROUND Motivation for high-fat food is thought to contribute to excess caloric intake in obese individuals. A novel regulator of motivation for food may be neuromedin U (NMU), a highly-conserved neuropeptide that influences food intake. Although these effects of NMU have primarily been attributed to signaling in the paraventricular nucleus of the hypothalamus (PVN), NMU has also been found in other brain regions involved in both feeding behavior and motivation. We investigate the effects of NMU on motivation for food and food intake, and identify the brain regions mediating these effects. METHODS The motivational state for a particular reinforcer (e.g., high-fat food) can be assessed using a progressive-ratio schedule of reinforcement under which an increasing number of lever presses are required to obtain subsequent reinforcers. Here, we have used a progressive-ratio operant responding paradigm in combination with an assessment of cumulative food intake to evaluate the effects of NMU administration in rats, and identify the brain regions mediating these effects. RESULTS We found that peripheral administration of NMU decreases operant responding for high-fat food in rats. Evaluation of Fos-like immunoreactivity in response to peripheral NMU indicated the PVN and dorsal raphe nucleus (DRN) as sites of action for NMU. NMU infusion into either region mimics the effects of peripheral NMU on food intake and operant responding for food. NMU-containing projections from the lateral hypothalamus (LH) to the PVN and DRN were identified as an endogenous source of NMU. CONCLUSIONS These results identify the DRN as a site of action for NMU, demonstrate that the LH provides endogenous NMU to the PVN and DRN and implicate NMU signaling in the PVN and DRN as a novel regulator of motivation for high-fat foods.
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Affiliation(s)
- David L. McCue
- Department of Neuroscience, University of Texas Medical Branch, Galveston, TX 77555-0615
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-0615
| | - James M. Kasper
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-0615
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555-0615
| | - Jonathan D. Hommel
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX 77555-0615
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555-0615
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17
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Vallöf D, Vestlund J, Engel JA, Jerlhag E. The Anorexigenic Peptide Neuromedin U (NMU) Attenuates Amphetamine-Induced Locomotor Stimulation, Accumbal Dopamine Release and Expression of Conditioned Place Preference in Mice. PLoS One 2016; 11:e0154477. [PMID: 27139195 PMCID: PMC4854378 DOI: 10.1371/journal.pone.0154477] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/14/2016] [Indexed: 12/28/2022] Open
Abstract
Amphetamine dependence, besides its substantial economical consequence, is a serious cause of mortality and morbidity. By investigations of the neurochemical correlates through which addictive drugs, such as amphetamine, activate the mesoaccumbal dopamine system unique targets for treatment of drug addiction can be identified. This reward link consists of a dopamine projection from the ventral tegmental area to the nucleus accumbens (NAc) suggesting that these brain areas are important for reward. The physiological function of gut-brain peptides has expanded beyond food intake modulation and involves regulation of drug reinforcement. A novel candidate for reward regulation is the anorexigenic peptide neuromedin U (NMU). We therefore investigated the effects of intracerebroventricular (icv) administration of NMU on amphetamine’s well-documented effects on the mesoaccumbal dopamine system, i.e. locomotor stimulation and accumbal dopamine release in mice. In addition, the effect of accumbal NMU administration on locomotor activity was examined. The effect of NMU, icv or intra-NAc, on the expression of conditioned place preference (CPP) was elucidated. Firstly, we showed that icv administration of NMU attenuate the amphetamine-induced locomotor stimulation, accumbal dopamine release and expression of CPP in mice. Secondly, we found that a lower dose of NMU (icv) reduce the amphetamine-induced locomotor stimulation in mice. Thirdly, we demonstrated that NMU administration into the NAc block the ability of amphetamine to cause a locomotor stimulation in mice. However, accumbal NMU administration did not attenuate the amphetamine-induced expression of CPP in mice. Our novel data suggest that central NMU signalling is involved in development of amphetamine dependence.
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Affiliation(s)
- Daniel Vallöf
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jesper Vestlund
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Jörgen A Engel
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Elisabet Jerlhag
- Institute of Neuroscience and Physiology, Department of Pharmacology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
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