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Azizifar N, Mohaddes G, Keyhanmanesh R, Athari SZ, Alimohammadi S, Farajdokht F. Intranasal AdipoRon Mitigated Anxiety and Depression-Like Behaviors in 6-OHDA-Induced Parkinson 's Disease Rat Model: Going Beyond Motor Symptoms. Neurochem Res 2024:10.1007/s11064-024-04223-8. [PMID: 39096412 DOI: 10.1007/s11064-024-04223-8] [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: 03/21/2024] [Revised: 07/02/2024] [Accepted: 07/29/2024] [Indexed: 08/05/2024]
Abstract
Depression and anxiety are prevalent neuropsychiatric conditions among patients with Parkinson's disease (PD), which may manifest prior to motor symptoms. As levodopa, a prominent treatment for PD motor symptoms, provides few benefits for mood-related abnormalities, tackling non-motor symptoms is particularly important. AdipoRon (Ad), an adiponectin agonist, has demonstrated neuroprotective effects by suppressing neuroinflammatory responses and activating the AMPK/Sirt-1 signaling pathway. This study looked at the potential advantages and underlying mechanisms of intranasal Ad in a rat model of PD induced by 6-hydroxydopamine (6-OHDA). We found that Ad at doses of 1 and 10 µg for 21 days exhibited anxiolytic- and antidepressant effects in the open field (OF) test, elevated plus maze (EPM), sucrose splash test, and forced swimming test in a PD model caused by a unilateral 6-OHDA injection into the medial forebrain bundle (MFB). The Ad also lowered the levels of corticosterone in the blood, decreased inflammasome components (NLRP3, caspase 1, and IL-1β), and increased Sirt-1 protein levels in the prefrontal cortex (PFC) of PD rats. We conclude that Ad ameliorates anxious and depressive-like behaviors in the PD rat model through stimulating the AMPK/Sirt-1 signaling and blocking the NLRP3 inflammasome pathways in the PFC.
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Affiliation(s)
- Negin Azizifar
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Gisou Mohaddes
- Department of Biomedical Education, College of Osteopathic Medicine, California Health Sciences University, Clovis, CA, USA
| | - Rana Keyhanmanesh
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Seyed Zanyar Athari
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Soraya Alimohammadi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Fereshteh Farajdokht
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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Okitsu M, Fujita M, Moriya Y, Kotajima-Murakami H, Ide S, Kojima R, Sekiyama K, Takahashi K, Ikeda K. Mouse Model of Parkinson's Disease with Bilateral Dorsal Striatum Lesion with 6-Hydroxydopamine Exhibits Cognitive Apathy-like Behavior. Int J Mol Sci 2024; 25:7993. [PMID: 39063235 PMCID: PMC11276653 DOI: 10.3390/ijms25147993] [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] [Received: 06/27/2024] [Revised: 07/11/2024] [Accepted: 07/18/2024] [Indexed: 07/28/2024] Open
Abstract
Among the symptoms of Parkinson's disease (PD), apathy comprises a set of behavioral, affective, and cognitive features that can be classified into several subtypes. However, the pathophysiology and brain regions that are involved in these different apathy subtypes are still poorly characterized. We examined which subtype of apathy is elicited in a mouse model of PD with 6-hydroxydopamine (6-OHDA) lesions and the behavioral symptoms that are exhibited. Male C57/BL6J mice were allocated to sham (n = 8) and 6-OHDA (n = 13) groups and locally injected with saline or 4 µg 6-OHDA bilaterally in the dorsal striatum. We then conducted motor performance tests and apathy-related behavioral experiments. We then pathologically evaluated tyrosine hydroxylase (TH) immunostaining. The 6-OHDA group exhibited significant impairments in motor function. In the behavioral tests of apathy, significant differences were observed between the sham and 6-OHDA groups in the hole-board test and novelty-suppressed feeding test. The 6-OHDA group exhibited impairments in inanimate novel object preference, whereas social preference was maintained in the three-chamber test. The number of TH+ pixels in the caudate putamen and substantia nigra compacta was significantly reduced in the 6-OHDA group. The present mouse model of PD predominantly showed dorsal striatum dopaminergic neuronal loss and a decrease in novelty seeking as a symptom that is related to the cognitive apathy component.
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Affiliation(s)
- Masato Okitsu
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (M.O.); (M.F.); (Y.M.); (H.K.-M.); (S.I.)
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo 183-0042, Japan;
| | - Masayo Fujita
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (M.O.); (M.F.); (Y.M.); (H.K.-M.); (S.I.)
| | - Yuki Moriya
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (M.O.); (M.F.); (Y.M.); (H.K.-M.); (S.I.)
| | - Hiroko Kotajima-Murakami
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (M.O.); (M.F.); (Y.M.); (H.K.-M.); (S.I.)
| | - Soichiro Ide
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (M.O.); (M.F.); (Y.M.); (H.K.-M.); (S.I.)
| | - Rika Kojima
- Laboratory of Molecular Pathology and Histology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (R.K.); (K.S.)
| | - Kazunari Sekiyama
- Laboratory of Molecular Pathology and Histology, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (R.K.); (K.S.)
| | - Kazushi Takahashi
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo 183-0042, Japan;
| | - Kazutaka Ikeda
- Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan; (M.O.); (M.F.); (Y.M.); (H.K.-M.); (S.I.)
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 187-8553, Japan
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Abomosallam M, Hendam BM, Abdallah AA, Refaat R, El-Hak HNG. Neuroprotective effect of Withania somnifera leaves extract nanoemulsion against penconazole-induced neurotoxicity in albino rats via modulating TGF-β1/Smad2 signaling pathway. Inflammopharmacology 2024; 32:1903-1928. [PMID: 38630361 PMCID: PMC11136823 DOI: 10.1007/s10787-024-01461-8] [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] [Received: 10/20/2023] [Accepted: 03/12/2024] [Indexed: 05/30/2024]
Abstract
Penconazole (PEN) is a systemic triazole fungicide used to control various fungal diseases on grapes, stone fruits, cucurbits, and strawberries. Still, it leaves residues on treated crops after collection with many hazardous effects on population including neurotoxicity. Withania somnifera leaves extract (WSLE) is known for its memory and brain function enhancing ability. To evoke such action efficiently, WSLE bioactive metabolites are needed to cross the blood-brain barrier, that could limit the availability of such compounds to be localized within the brain. Therefore, in the present study, the association between PEN exposure and neurotoxicity was evaluated, and formulated WSLE nanoemulsion was investigated for improving the permeability of the plant extract across the blood-brain barrier. The rats were divided into five groups (n = 6). The control group was administered distilled water, group II was treated with W. somnifera leaves extract nanoemulsion (WSLE NE), group III received PEN, group IV received PEN and WSLE, and group V received PEN and WSLE NE. All rats were gavaged daily for 6 weeks. Characterization of compounds in WSLE using LC-MS/MS analysis was estimated. Neurobehavioral disorders were evaluated in all groups. Oxidative stress biomarkers, antioxidant enzyme activities, and inflammatory cytokines were measured in brain tissue. Furthermore, the gene expression patterns of GFAP, APP, vimentin, TGF-β1, Smad2 and Bax were measured. Histopathological changes and immunohistochemical expression in the peripheral sciatic nerve and cerebral cortex were evaluated. A total of 91 compounds of different chemo-types were detected and identified in WSLE in both ionization modes. Our data showed behavioral impairment in the PEN-treated group, with significant elevation of oxidative stress biomarkers, proinflammatory cytokines, neuronal damage, and apoptosis. In contrast, the PEN-treated group with WSLE NE showed marked improvement in behavioral performance and histopathological alteration with a significant increase in antioxidant enzyme activity and anti-inflammatory cytokines compared to the group administered WSLE alone. The PEN-treated group with WSLE NE in turn significantly downregulated the expression levels of GFAP, APP, vimentin, TGF-β1, Smad2 and Bax in brain tissue. In conclusion, WSLE NE markedly enhanced the permeability of plant extract constituents through the blood brain barrier to boost its neuroprotective effect against PEN-induced neurotoxicity.
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Affiliation(s)
- Mohamed Abomosallam
- Forensic Medicine and Toxicology Department, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
| | - Basma M Hendam
- Department of Husbandry and Development of Animal Wealth, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
| | - Amr A Abdallah
- Central Agricultural Pesticides Laboratory, Agricultural Research Center, Giza, Egypt
| | - Rasha Refaat
- Phytochemistry and Plant Systematics Department, National Research Centre, Dokki, Cairo, Egypt
| | - Heba Nageh Gad El-Hak
- Zoology Department, Faculty of Science, Suez Canal University, 10, Ismailia, 41522, Egypt.
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Arzua T, Yan Y, Liu X, Dash RK, Liu QS, Bai X. Synaptic and mitochondrial mechanisms behind alcohol-induced imbalance of excitatory/inhibitory synaptic activity and associated cognitive and behavioral abnormalities. Transl Psychiatry 2024; 14:51. [PMID: 38253552 PMCID: PMC10803756 DOI: 10.1038/s41398-024-02748-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 01/02/2024] [Accepted: 01/08/2024] [Indexed: 01/24/2024] Open
Abstract
Alcohol consumption during pregnancy can significantly impact the brain development of the fetus, leading to long-term cognitive and behavioral problems. However, the underlying mechanisms are not well understood. In this study, we investigated the acute and chronic effects of binge-like alcohol exposure during the third trimester equivalent in postnatal day 7 (P7) mice on brain cell viability, synapse activity, cognitive and behavioral performance, and gene expression profiles at P60. Our results showed that alcohol exposure caused neuroapoptosis in P7 mouse brains immediately after a 6-hour exposure. In addition, P60 mice exposed to alcohol during P7 displayed impaired learning and memory abilities and anxiety-like behaviors. Electrophysiological analysis of hippocampal neurons revealed an excitatory/inhibitory imbalance in alcohol-treated P60 mice compared to controls, with decreased excitation and increased inhibition. Furthermore, our bioinformatic analysis of 376 dysregulated genes in P60 mouse brains following alcohol exposure identified 50 synapse-related and 23 mitochondria-related genes. These genes encoded proteins located in various parts of the synapse, synaptic cleft, extra-synaptic space, synaptic membranes, or mitochondria, and were associated with different biological processes and functions, including the regulation of synaptic transmission, transport, synaptic vesicle cycle, metabolism, synaptogenesis, mitochondrial activity, cognition, and behavior. The dysregulated synapse and mitochondrial genes were predicted to interact in overlapping networks. Our findings suggest that altered synaptic activities and signaling networks may contribute to alcohol-induced long-term cognitive and behavioral impairments in mice, providing new insights into the underlying synaptic and mitochondrial molecular mechanisms and potential neuroprotective strategies.
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Affiliation(s)
- Thiago Arzua
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Yasheng Yan
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Xiaojie Liu
- Department of Pharmacology, Medical College of Wisconsin, Milwaukee, 53226, WI, USA
| | - Ranjan K Dash
- Department of Biomedical Engineering, Medical College of Wisconsin, Milwaukee, 53226, WI, USA
| | - Qing-Song Liu
- Department of Pharmacology, Medical College of Wisconsin, Milwaukee, 53226, WI, USA
| | - Xiaowen Bai
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
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Xu Y, Gao W, Sun Y, Wu M. New insight on microglia activation in neurodegenerative diseases and therapeutics. Front Neurosci 2023; 17:1308345. [PMID: 38188026 PMCID: PMC10770846 DOI: 10.3389/fnins.2023.1308345] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 12/06/2023] [Indexed: 01/09/2024] Open
Abstract
Microglia are immune cells within the central nervous system (CNS) closely linked to brain health and neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. In response to changes in the surrounding environment, microglia activate and change their state and function. Several factors, example for circadian rhythm disruption and the development of neurodegenerative diseases, influence microglia activation. In this review, we explore microglia's function and the associated neural mechanisms. We elucidate that circadian rhythms are essential factors influencing microglia activation and function. Circadian rhythm disruption affects microglia activation and, consequently, neurodegenerative diseases. In addition, we found that abnormal microglia activation is a common feature of neurodegenerative diseases and an essential factor of disease development. Here we highlight the importance of microglia activation in neurodegenerative diseases. Targeting microglia for neurodegenerative disease treatment is a promising direction. We introduce the progress of methods targeting microglia for the treatment of neurodegenerative diseases and summarize the progress of drugs developed with microglia as targets, hoping to provide new ideas for treating neurodegenerative diseases.
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Affiliation(s)
- Yucong Xu
- Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- The Key Laboratory of Carcinogenesis of the Chinese Ministry of Health, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, Hunan, China
| | - Wei Gao
- Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- The Key Laboratory of Carcinogenesis of the Chinese Ministry of Health, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, Hunan, China
| | - Yingnan Sun
- Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
| | - Minghua Wu
- Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- The Key Laboratory of Carcinogenesis of the Chinese Ministry of Health, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, Hunan, China
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Borgonetti V, Mugnaini C, Corelli F, Galeotti N. The Selective CB2 Agonist COR167 Reduced Symptoms in a Mice Model of Trauma-Induced Peripheral Neuropathy through HDAC-1 Inhibition. Biomedicines 2023; 11:1546. [PMID: 37371642 DOI: 10.3390/biomedicines11061546] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 05/21/2023] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
Neuropathic pain is a chronic disabling condition with a 7-10% of prevalence in the general population that is largely undertreated. Available analgesic therapies are poorly effective and are often accompanied by numerous side effects. Growing evidence indicates cannabinoids are a valuable treatment opportunity for neuropathic pain. The endocannabinoid system is an important regulator of pain perception through the CB1 receptors, but CB1 agonists, while largely effective, are not always satisfactory pain-relieving agents in clinics because of their serious adverse effects. Recently, several CB2 agonists have shown analgesic, anti-hyperalgesic, and anti-allodynic activity in the absence of CB1-induced psychostimulant effects, offering promise in neuropathic pain management. The aim of this study was to evaluate the anti-neuropathic activity of a novel selective CB2 agonist, COR167, in a preclinical model of peripheral neuropathy, the spared nerve injury (SNI). Oral COR167, in a dose-dependent manner, attenuated mechanical allodynia and thermal hyperalgesia after acute and repeated administration, showing the absence of tolerance induction. At anti-neuropathic doses, COR167 did not show any alteration in the locomotor behavior. SNI mice showed increased microglial levels of HDAC1 protein in the ipsilateral side of the spinal cord, along with NF-kB activation. COR167 treatment prevented the HDAC1 overexpression and the NF-kB activation and increased the levels of the anti-inflammatory cytokine IL-10 through a CB2-mediated mechanism. Oral administration of COR167 shows promising therapeutic potential in the management of neuropathic pain conditions.
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Affiliation(s)
- Vittoria Borgonetti
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Claudia Mugnaini
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Federico Corelli
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy
| | - Nicoletta Galeotti
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, Viale G. Pieraccini 6, 50139 Florence, Italy
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He Y, Jia H, Yang Q, Shan W, Chen X, Huang X, Liu T, Sun R. Specific Activation of CB2R Ameliorates Psoriasis-Like Skin Lesions by Inhibiting Inflammation and Oxidative Stress. Inflammation 2023:10.1007/s10753-023-01805-6. [PMID: 37000322 DOI: 10.1007/s10753-023-01805-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 03/09/2023] [Accepted: 03/10/2023] [Indexed: 04/01/2023]
Abstract
Psoriasis is a chronic inflammatory skin disease. Inflammation and oxidative stress play crucial roles in the pathogenesis of psoriasis. Cannabinoid receptor type 2 (CB2R) is an attractive target for treating various inflammatory disorders. However, the precise role and mechanism of CB2R activation in psoriasis remain to be further elucidated. In this study, imiquimod (IMQ)-induced experimental psoriasis mice and tumor necrosis factor-α (TNF-α)-activated keratinocytes (HaCaT) were used to examine the effect of CB2R activation on psoriasis-like lesions and the mechanism in vivo and in vitro. Our results demonstrated that activation of CB2R by the specific agonist GW842166X (GW) significantly ameliorated IMQ-induced psoriasiform skin lesions in mice by reducing epidermal thickness and decreasing plaque thickness. On the one hand, GW alleviated inflammation by decreasing inflammatory cytokines and abating inflammatory cell infiltration. On the other hand, this treatment reduced the level of iNOS and downregulated the expression of CB2R in psoriatic skin tissue. Further studies suggested that the Kelch-like ECH-associated protein 1/nuclear factor erythroid-2-related factor (Keap1/Nrf2) signaling pathway might be involved. Our findings reveal that selective activation of CB2R may serve as a new strategy for the treatment of psoriasis.
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Affiliation(s)
- Yufeng He
- Department of Dermatology, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Honglin Jia
- Department of Dermatology, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Qunfang Yang
- Department of Pharmacology, College of Pharmacy and Laboratory Medicine, Army Medical University, Chongqing, 400038, China
| | - Wenjun Shan
- Department of Pharmacology, College of Pharmacy and Laboratory Medicine, Army Medical University, Chongqing, 400038, China
| | - Xiaohong Chen
- Department of Pharmacology, College of Pharmacy and Laboratory Medicine, Army Medical University, Chongqing, 400038, China
| | - Xianqiong Huang
- Department of Dermatology, Daping Hospital, Army Medical University, Chongqing, 400042, China
| | - Tao Liu
- Department of Pharmacology, College of Pharmacy and Laboratory Medicine, Army Medical University, Chongqing, 400038, China.
| | - Renshan Sun
- Department of Dermatology, Daping Hospital, Army Medical University, Chongqing, 400042, China.
- Department of Dermatology, Health Science Center, South China Hospital, Shenzhen University, Guangdong, 518116, China.
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Liu X, Vickstrom CR, Yu H, Liu S, Snarrenberg ST, Friedman V, Mu L, Chen B, Kelly TJ, Baker DA, Liu QS. Epac2 in midbrain dopamine neurons contributes to cocaine reinforcement via facilitation of dopamine release. eLife 2022; 11:80747. [PMID: 35993549 PMCID: PMC9436413 DOI: 10.7554/elife.80747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 08/21/2022] [Indexed: 11/21/2022] Open
Abstract
Repeated exposure to drugs of abuse results in an upregulation of cAMP signaling in the mesolimbic dopamine system, a molecular adaptation thought to be critically involved in the development of drug dependence. Exchange protein directly activated by cAMP (Epac2) is a major cAMP effector abundantly expressed in the brain. However, it remains unknown whether Epac2 contributes to cocaine reinforcement. Here, we report that Epac2 in the mesolimbic dopamine system promotes cocaine reinforcement via enhancement of dopamine release. Conditional knockout of Epac2 from midbrain dopamine neurons (Epac2-cKO) and the selective Epac2 inhibitor ESI-05 decreased cocaine self-administration in mice under both fixed-ratio and progressive-ratio reinforcement schedules and across a broad range of cocaine doses. In addition, Epac2-cKO led to reduced evoked dopamine release, whereas Epac2 agonism robustly enhanced dopamine release in the nucleus accumbens in vitro. This mechanism is central to the behavioral effects of Epac2 disruption, as chemogenetic stimulation of ventral tegmental area (VTA) dopamine neurons via deschloroclozapine (DCZ)-induced activation of Gs-DREADD increased dopamine release and reversed the impairment of cocaine self-administration in Epac2-cKO mice. Conversely, chemogenetic inhibition of VTA dopamine neurons with Gi-DREADD reduced dopamine release and cocaine self-administration in wild-type mice. Epac2-mediated enhancement of dopamine release may therefore represent a novel and powerful mechanism that contributes to cocaine reinforcement.
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Affiliation(s)
- Xiaojie Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Casey R Vickstrom
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Hao Yu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Shuai Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Shana Terai Snarrenberg
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Vladislav Friedman
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Lianwei Mu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Bixuan Chen
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - Thomas J Kelly
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
| | - David A Baker
- Department of Biomedical Sciences, Marquette University, Milwaukee, United States
| | - Qing-Song Liu
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, United States
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