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Cho BR, Kim WY, Jang JK, Lee JW, Kim JH. Glycogen Synthase Kinase 3β Is a Key Regulator in the Inhibitory Effects of Accumbal Cocaine- and Amphetamine-Regulated Transcript Peptide 55-102 on Amphetamine-Induced Locomotor Activity. Int J Mol Sci 2022; 23:ijms232415633. [PMID: 36555273 PMCID: PMC9779470 DOI: 10.3390/ijms232415633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/06/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022] Open
Abstract
Microinjection of cocaine- and amphetamine-regulated transcript (CART) peptide 55-102 into the nucleus accumbens (NAcc) core significantly attenuates psychostimulant-induced locomotor activity. However, the molecular mechanism remains poorly understood. We examined the phosphorylation levels of Akt, glycogen synthase kinase 3β (GSK3β), and glutamate receptor 1 (GluA1) in NAcc core tissues obtained 60 min after microinjection of CART peptide 55-102 into this site, followed by systemic injection of amphetamine (AMPH). Phosphorylation levels of Akt at Thr308 and GSK3β at Ser9 were decreased, while those of GluA1 at Ser845 were increased, by AMPH treatment. These effects returned to basal levels following treatment with CART peptide 55-102. Furthermore, the negative regulatory effects of the CART peptide on AMPH-induced changes in phosphorylation levels and locomotor activity were all abolished by pretreatment with the S9 peptide, an artificially synthesized indirect GSK3β activator. These results suggest that the CART peptide 55-102 in the NAcc core plays a negative regulatory role in AMPH-induced locomotor activity by normalizing the changes in phosphorylation levels of Akt-GSK3β, and subsequently GluA1 modified by AMPH at this site. The present findings are the first to reveal GSK3β as a key regulator of the inhibitory role of the CART peptide in psychomotor stimulant-induced locomotor activity.
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Affiliation(s)
- Bo Ram Cho
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, USA
| | - Wha Young Kim
- Department of Physiology, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Ju Kyong Jang
- Department of Pharmacology, Bio-Pharm Solutions Co., Ltd., Suwon-si 16229, Gyeonggi-do, Republic of Korea
| | - Jung Won Lee
- Division of In Vitro Diagnostic Devices, National Institute of Food and Drug Safety Evaluation, Cheongju-si 28159, Chungcheongbuk-do, Republic of Korea
| | - Jeong-Hoon Kim
- Department of Physiology, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
- Department of Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
- Correspondence:
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Brandão SR, Carvalho F, Amado F, Ferreira R, Costa VM. Insights on the molecular targets of cardiotoxicity induced by anticancer drugs: A systematic review based on proteomic findings. Metabolism 2022; 134:155250. [PMID: 35809654 DOI: 10.1016/j.metabol.2022.155250] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/02/2022] [Accepted: 06/26/2022] [Indexed: 11/27/2022]
Abstract
Several anticancer agents have been associated with cardiac toxic effects. The currently proposed mechanisms to explain cardiotoxicity differ among anticancer agents, but in fact, the specific modulation is not completely elucidated. Thus, this systematic review aims to provide an integrative perspective of the molecular mechanisms underlying the toxicity of anticancer agents on heart muscle while using a high-throughput technology, mass spectrometry (MS)-based proteomics. A literature search using PubMed database led to the selection of 27 studies, of which 13 reported results exclusively on animal models, 13 on cardiomyocyte-derived cell lines and only one included both animal and a cardiomyocyte line. The reported anticancer agents were the proteasome inhibitor carfilzomib, the anthracyclines daunorubicin, doxorubicin, epirubicin and idarubicin, the antimicrotubule agent docetaxel, the alkylating agent melphalan, the anthracenedione mitoxantrone, the tyrosine kinase inhibitors (TKIs) erlotinib, lapatinib, sorafenib and sunitinib, and the monoclonal antibody trastuzumab. Regarding the MS-based proteomic approaches, electrophoretic separation using two-dimensional (2D) gels coupled with tandem MS (MS/MS) and liquid chromatography-MS/MS (LC-MS/MS) were the most common. Overall, the studies highlighted 1826 differentially expressed proteins across 116 biological processes. Most of them were grouped in larger processes and critically analyzed in the present review. The selection of studies using proteomics on heart muscle allowed to obtain information about the anticancer therapy-induced modulation of numerous proteins in this tissue and to establish connections that have been disregarded in other studies. This systematic review provides interesting points for a comprehensive understanding of the cellular cardiotoxicity mechanisms of different anticancer drugs.
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Affiliation(s)
- Sofia Reis Brandão
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; UCIBIO-Applied Molecular Biosciences Unit, REQUIMTE, Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira n° 28, 4050-313 Porto, Portugal; LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Félix Carvalho
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; UCIBIO-Applied Molecular Biosciences Unit, REQUIMTE, Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira n° 28, 4050-313 Porto, Portugal
| | - Francisco Amado
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Rita Ferreira
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Vera Marisa Costa
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; UCIBIO-Applied Molecular Biosciences Unit, REQUIMTE, Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira n° 28, 4050-313 Porto, Portugal.
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3
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Ugur M, Kanit L, Koylu EO, Balkan B, Gözen O. Cocaine- and amphetamine-regulated transcript promoter regulated by nicotine in nerve growth factor-treated PC12 cells. Physiol Int 2019; 106:272-282. [DOI: 10.1556/2060.106.2019.27] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nicotine and cocaine- and amphetamine-regulated transcripts (CART) have several overlapping functions, such as the regulation of reward, feeding behavior, stress response, and anxiety. Previous studies showed that nicotine regulates CART expression in various brain regions. However, the molecular mechanisms underlying this regulation are not known. This study investigated the regulatory effect of nicotine on promoter activity of the CART gene in PC12 cells, which were differentiated into a neuronal phenotype by nerve growth factor (NGF) treatment. Two vectors containing reporter genes (Gaussia luciferase or mCherry) and the 1,140-bp upstream of the transcriptional start site of the mouse CART gene are used to analyze the CART promoter activity. Transient transfection of PC12 cells with either vector displayed strong promoter activity in both undifferentiated and differentiated PC12 cells. CART promoter activity in the PC12 cell line is increased by forskolin or NGF treatment. In differentiated PC12 cells, exposure to 50 nM nicotine for 6 h increased CART promoter activity. However, treatment with higher nicotine doses for 6 h and treatment with all nicotine doses for 24 h showed no effect. A nicotine concentration of 50 nM is comparable to brain nicotine levels experienced by chronic smokers over long periods of time. Taken together, these data indicate that nicotine may exert some of its actions through the regulation of CART transcription in the brain.
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Affiliation(s)
- M Ugur
- 1 Department of Physiology, Ege University School of Medicine, Izmir, Turkey
| | - L Kanit
- 1 Department of Physiology, Ege University School of Medicine, Izmir, Turkey
- 2 Ege University Center for Brain Research, Izmir, Turkey
| | - EO Koylu
- 1 Department of Physiology, Ege University School of Medicine, Izmir, Turkey
- 2 Ege University Center for Brain Research, Izmir, Turkey
| | - B Balkan
- 1 Department of Physiology, Ege University School of Medicine, Izmir, Turkey
- 2 Ege University Center for Brain Research, Izmir, Turkey
| | - O Gözen
- 1 Department of Physiology, Ege University School of Medicine, Izmir, Turkey
- 2 Ege University Center for Brain Research, Izmir, Turkey
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Ahmadian-Moghadam H, Sadat-Shirazi MS, Zarrindast MR. Cocaine- and amphetamine-regulated transcript (CART): A multifaceted neuropeptide. Peptides 2018; 110:56-77. [PMID: 30391426 DOI: 10.1016/j.peptides.2018.10.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 10/15/2018] [Accepted: 10/29/2018] [Indexed: 12/12/2022]
Abstract
Over the last 35 years, the continuous discovery of novel neuropeptides has been the key to the better understanding of how the central nervous system has integrated with neuronal signals and behavioral responses. Cocaine and amphetamine-regulated transcript (CART) was discovered in 1995 in the rat striatum but later was found to be highly expressed in the hypothalamus. The widespread distribution of CART peptide in the brain complicated the understanding of the role played by this neurotransmitter. The main objective of the current compact review is to piece together the fragments of available information about origin, expression, distribution, projection, and function of CART peptides. Accumulative evidence suggests CART as a neurotransmitter and neuroprotective agent that is mainly involved in regulation of feeding, addiction, stress, anxiety, innate fear, neurological disease, neuropathic pain, depression, osteoporosis, insulin secretion, learning, memory, reproduction, vision, sleep, thirst and body temperature. In spite of the vast number of studies about the CART, the overall pictures about the CART functions are sketchy. First, there is a lack of information about cloned receptor, specific agonist and antagonist. Second, CART peptides are detected in discrete sets of neurons that can modulate countless activities and third; CART peptides exist in several fragments due to post-translational processing. For these reasons the overall picture about the CART peptides are sketchy and confounding.
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Affiliation(s)
- Hamid Ahmadian-Moghadam
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Mohammad-Reza Zarrindast
- Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Endocrinology and Metabolism Research Institute, Tehran University of Medical Science, Tehran, Iran.
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Xiong L, Meng Q, Sun X, Lu X, Fu Q, Peng Q, Yang J, Oh KW, Hu Z. Cocaine- and amphetamine-regulated transcript peptide in the nucleus accumbens shell inhibits cocaine-induced locomotor sensitization to transient over-expression of α-Ca 2+ /calmodulin-dependent protein kinase II. J Neurochem 2018; 146:289-303. [PMID: 29313985 DOI: 10.1111/jnc.14289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 12/15/2017] [Accepted: 12/18/2017] [Indexed: 11/29/2022]
Abstract
Cocaine- and amphetamine-regulated transcript (CART) peptide is a widely distributed neurotransmitter that attenuates cocaine-induced locomotor activity when injected into the nucleus accumbens (NAc). Our previous work first confirmed that the inhibitory mechanism of the CART peptide on cocaine-induced locomotor activity is related to a reduction in cocaine-enhanced phosphorylated Ca2+ /calmodulin-dependent protein kinaseIIα (pCaMKIIα) and the enhancement of cocaine-induced D3R function. This study investigated whether CART peptide inhibited cocaine-induced locomotor activity via inhibition of interactions between pCaMKIIα and the D3 dopamine receptor (D3R). We demonstrated that lentivirus-mediated gene transfer transiently increased pCaMKIIα expression, which peaked at 10 days after microinjection into the rat NAc shell, and induced a significant increase in Ca2+ influx along with greater behavioral sensitivity in the open field test after intraperitoneal injections of cocaine (15 mg/kg). However, western blot analysis and coimmunoprecipitation demonstrated that CART peptide treatment in lentivirus-transfected CaMKIIα-over-expressing NAc rat tissues or cells prior to cocaine administration inhibited the cocaine-induced Ca2+ influx and attenuated the cocaine-increased pCaMKIIα expression in lentivirus-transfected CaMKIIα-over-expressing cells. CART peptide decreased the cocaine-enhanced phosphorylated cAMP response element binding protein (pCREB) expression via inhibition of the pCaMKIIα-D3R interaction, which may account for the prolonged locomotor sensitization induced by repeated cocaine treatment in lentivirus-transfected CaMKIIα-over-expressing cells. These results provide strong evidence for the inhibitory modulation of CART peptide in cocaine-induced locomotor sensitization. Cover Image for this issue: doi: 10.1111/jnc.14187.
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Affiliation(s)
- Lixia Xiong
- Department of Pathophysiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Qing Meng
- Queen Mary Institute, School of Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Xi Sun
- Anhui Sinobioway Cell Therapy CO., LTD, Hefei, Anhui, China
| | - Xiangtong Lu
- Department of Pathophysiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Qiang Fu
- Department of Respiration, The Fourth Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China.,Department of Respiration, Department Two, Jiangxi Provincial People's Hospital, Nanchang, Jiangxi, China
| | - Qinghua Peng
- Department of Anesthesiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China
| | - Jianhua Yang
- Department of Physiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Ki-Wan Oh
- College of Pharmacy, Chungbuk National University, Cheongju, Korea
| | - Zhenzhen Hu
- Department of Pathophysiology, College of Basic Medicine, Nanchang University, Nanchang, Jiangxi, China.,Jiangxi Province Key laboratory of Tumor Pathogens and Molecular Pathology and the Department of Pathology, Schools of Basic Medical Sciences and Pharmaceutical Sciences, Nanchang University Medical College, Nanchang, China
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Borkar CD, Bharne AP, Nagalakshmi B, Sakharkar AJ, Subhedar NK, Kokare DM. Cocaine- and Amphetamine-Regulated Transcript Peptide (CART) Alleviates MK-801-Induced Schizophrenic Dementia-Like Symptoms. Neuroscience 2018; 375:94-107. [PMID: 29425773 DOI: 10.1016/j.neuroscience.2018.01.056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 01/22/2018] [Accepted: 01/28/2018] [Indexed: 10/18/2022]
Abstract
Exaggerated thoughts, diminished mood and impaired cognition are the hallmarks of the schizophrenia-like condition. These symptoms are attributed to the dysregulation of dopamine and glutamate signaling in the brain. Since cocaine- and amphetamine-regulated transcript peptide (CART) modulates actions of dopamine as well as glutamate, we tested the role of this peptide in MK-801-induced schizophrenic dementia-like condition. MK-801-treated rats were allowed to interact with conspecific juvenile and tested for short-term (30-min) and long-term (24-h) social memory acquisition and recall. While MK-801 impaired the social interaction with a juvenile, the behavior was restored in CART [intracerebroventricular (icv) or intra-ventral tegmental area (VTA)] pre-treated animals. This action of CART was blocked by SCH23390 (dopamine D1 receptor antagonist) administered directly into the prefrontal cortex (PFC). Application of neuronal tracer Di-I in the PFC retrogradely labeled dopamine cells of the VTA, which in turn seem to receive CARTergic innervation. A significant increase in CARTimmunoreactivity was evidenced in the VTA, PFC and accumbens of the animals allowed to interact with a juvenile. However, MK-801 treatment attenuated the peptide expression and induced social memory deficits. The schizophrenic dementia-like symptoms following antagonism of glutamatergic receptors may be attributed to the reduced dopamine activity in the mesocortical system. We suggest that CART may, positively modulate the dopamine system to alleviate cognitive deficits associated with schizophrenia.
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Affiliation(s)
- Chandrashekhar D Borkar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India
| | - Ashish P Bharne
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India
| | - B Nagalakshmi
- Department of Biotechnology, Savitribai Phule Pune University, Pune 411 007, Maharashtra, India
| | - Amul J Sakharkar
- Department of Biotechnology, Savitribai Phule Pune University, Pune 411 007, Maharashtra, India
| | - Nishikant K Subhedar
- Indian Institute of Science Education and Research, Dr Homi Bhabha Road, Pune 411 008, Maharashtra, India
| | - Dadasaheb M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India.
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Li P, Yu X, Xie J, Yao X, Liu W, Yao J, Zhu Z, Lyu L. Expression of cocaine- and amphetamine-regulated transcript (CART) in hen ovary. Biol Res 2017; 50:18. [PMID: 28532517 PMCID: PMC5440929 DOI: 10.1186/s40659-017-0123-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 05/13/2017] [Indexed: 11/12/2022] Open
Abstract
Background Cocaine- and amphetamine-regulated transcript (CART), discovered initially by via differential display RT-PCR analysis of brains of rats administered cocaine, is expressed mainly in central nervous system or neuronal origin cells, and is involved in a wide range of behaviors, such as regulation of food intake, energy homeostasis, and reproduction. The hens egg-laying rate mainly depends on the developmental status of follicles, expression of CART have not been identified from hen follicles, the regulatory mechanisms of CART biological activities are still unknown. The objective of this study was to characterize the mRNA expression of CART in hen follicular granulosa cells and determine CART peptide localization and regulatory role during follicular development. Methods Small white follicles (1–2 mm in diameter) were treated for RNA isolation; Small white follicles (1–2 mm in diameter) and large white follicles (4–6 mm in diameter) were treated for immunohistochemical localization and large white follicles (4–6 mm in diameter), small yellow follicles (6–8 mm in diameter), large yellow follicles (9–12 mm in diameter), mature follicles (F5, F4, F3, F2, F1, >12 mm in diameter) were treated for RNA isolation and Real time PCR. Results The results showed that full length of the CDS of hen CART was 336 bp encoding a 111 amino acid polypeptide. In the hen ovary, CART peptide was primarily localized to the theca layer, but not all, the oocyte and granulosa layer, with diffused, weaker staining than relative to the theca cell layer. Further, amount of CART mRNA was more (P < 0.05) in granulosa cells of 6–8 mm follicles compared with that in granulosa cells of other follicles. However, CART mRNA amount was greater in theca cells of 4–6 mm follicles relative to follicles of other sizes (P < 0.05). Conclusions Results suggest that CART could play a potential role in developmental regulation of chicken follicles.
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Affiliation(s)
- Pengfei Li
- College of Life Science, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Xuejing Yu
- College of Animal Science and Technology, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Jianshan Xie
- School of Basic Medical Sciences, Shanxi Medical University, Taiyuan, 030001, Shanxi, China
| | - Xiaolei Yao
- College of Animal Science and Technology, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Wenzhong Liu
- College of Animal Science and Technology, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Jianbo Yao
- College of Animal Science and Technology, Shanxi Agricultural University, Taigu, 030801, Shanxi, China.,Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Zhiwei Zhu
- College of Life Science, Shanxi Agricultural University, Taigu, 030801, Shanxi, China
| | - Lihua Lyu
- College of Animal Science and Technology, Shanxi Agricultural University, Taigu, 030801, Shanxi, China.
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Valdés-Moreno MI, Alcántara-Alonso V, Estrada-Camarena E, Mengod G, Amaya MI, Matamoros-Trejo G, de Gortari P. Phosphodiesterase-7 inhibition affects accumbal and hypothalamic thyrotropin-releasing hormone expression, feeding and anxiety behavior of rats. Behav Brain Res 2017; 319:165-173. [PMID: 27864049 DOI: 10.1016/j.bbr.2016.11.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 10/24/2016] [Accepted: 11/14/2016] [Indexed: 12/19/2022]
Abstract
Thyrotropin-releasing hormone (TRH) has anorexigenic and anxiolytic functions when injected intraventricularly. Nucleus accumbens (NAcc) is a possible brain region involved, since it expresses proTRH. TRH from hypothalamic paraventricular nucleus (PVN) has a food intake-regulating role. TRHergic pathways of NAcc and PVN are implicated in anxiety and feeding. Both behaviors depend on cAMP and phosphorylated-cAMP response element binding protein (pCREB) intracellular levels. Intracellular levels of cAMP are controlled by the degrading activity of phosphodiesterases (PDEs). Since TRH transcription is activated by pCREB, a specific inhibitor of PDE7B may regulate TRH-induced effects on anxiety and feeding. We evaluated the effectiveness of an intra-accumbal and intraperitoneal (i.p.) administration of a PDE7 inhibitor (BRL-50481) on rats' anxiety-like behavior and food intake; also on TRH mRNA and protein expression in NAcc and PVN to define its mediating role on the PDE7 inhibitor-induced behavioral changes. Accumbal injection of 4μg/0.3μL of PDE7 inhibitor decreased rats' anxiety. The i.p. injection of 0.2mg/kg of the inhibitor was able to increase the PVN TRH mRNA expression and to decrease feeding but did not change animals' anxiety levels; in contrast, 2mg/kg b.w inhibitor enhanced accumbal TRH mRNA, induced anxiolysis with no change in food intake. PDE7 inhibitor induced anxiolytic and anorexigenic like behavior depending on the dose used. Results supported hypothalamic TRH mediated feeding-reduction effects, and accumbal TRH mediation of inhibitor-induced anxiolysis. Thus, an i.p dose of this inhibitor might be reducing anxiety with no change in feeding, which could be useful for obese patients.
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Affiliation(s)
- M I Valdés-Moreno
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico; School of Dietetics and Nutrition ISSSTE, Callejón Vía San Fernando 12, Col. San Pedro Apóstol, 14070 México City, Mexico
| | - V Alcántara-Alonso
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - E Estrada-Camarena
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - G Mengod
- Department of Neurochemistry and Neuropharmachology, Institut d'Investigacions Biòmediques de Barcelona, CSIC, IDIBAPS, CIBERNED, c/Rosselló 161, 6a, E 08036 Barcelona, Spain
| | - M I Amaya
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - G Matamoros-Trejo
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico
| | - P de Gortari
- Department of Neuroscience Research, National Institute of Psychiatry RFM, Calzada México Xochimilco 101, Col. San Lorenzo Huipulco, 14370 México City, Mexico.
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Xu W, Zhang Y, Bai M, Zhou F, Deng R, Ji X, Zhang J, Liu Y, Zhou L, Wang X. Glucose enhances rat islet function via stimulating CART expression. Biochem Biophys Res Commun 2016; 481:84-89. [PMID: 27823935 DOI: 10.1016/j.bbrc.2016.11.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 11/03/2016] [Indexed: 12/30/2022]
Abstract
Cocaine- and amphetamine-regulated transcript (CART) is an anorexigenic peptide widely expressed in the central and peripheral nervous systems, as well as in endocrine cells. CART is markedly upregulated in the β-cells of several rodent models of type-2 diabetes. The stimulatory effect of exogenous CART peptide on insulin secretion is cAMP dependent. Glucose is the most important regulator of islet function. However, the role of CART in glucose-potentiated insulin secretion remains unclear. Here, our results showed that glucose time- and dose-dependently elicited CART mRNA expression in rat islets. Both the glucokinase agonist GKA50 and the long-acting GLP-1 analogue exendin-4 increased CART mRNA expression. The protein kinase A (PKA) inhibitor H89 and the inactivation of cAMP response element-binding protein (CREB) suppressed forskolin-stimulated CART mRNA expression. Furthermore, CART overexpression amplified insulin secretion from rat islets in response to glucose and forskolin, and ameliorated dexamethasone-impaired insulin secretion. These findings suggest that islet-derived CART is involved, at least in part, in high glucose-potentiated pancreatic β-cell function.
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Affiliation(s)
- Wan Xu
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Yuqing Zhang
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Mengyao Bai
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Feiye Zhou
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Ruyuan Deng
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Xueying Ji
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Juan Zhang
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Yun Liu
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China
| | - Libin Zhou
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
| | - Xiao Wang
- Shanghai Clinical Center for Endocrine and Metabolic Diseases, Shanghai Institute of Endocrine and Metabolic Diseases, Department of Endocrine and Metabolic Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
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Fu Q, Zhou X, Dong Y, Huang Y, Yang J, Oh KW, Hu Z. Decreased Caffeine-Induced Locomotor Activity via Microinjection of CART Peptide into the Nucleus Accumbens Is Linked to Inhibition of the pCaMKIIa-D3R Interaction. PLoS One 2016; 11:e0159104. [PMID: 27404570 PMCID: PMC4942143 DOI: 10.1371/journal.pone.0159104] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 06/27/2016] [Indexed: 11/19/2022] Open
Abstract
The purpose of this study was to characterize the inhibitory modulation of cocaine- and amphetamine-regulated transcript (CART) peptides, particularly with respect to the function of the D3 dopamine receptor (D3R), which is activated by its interaction with phosphorylated CaMKIIα (pCaMKIIα) in the nucleus accumbens (NAc). After repeated oral administration of caffeine (30 mg/kg) for five days, microinjection of CART peptide (0.08 μM/0.5 μl/hemisphere) into the NAc affected locomotor behavior. The pCaMKIIα-D3R interaction, D3R phosphorylation and cAMP/PKA/phosphorylated CREB (pCREB) signaling pathway activity were measured in NAc tissues, and Ca2+ influx and pCaMKIIα levels were measured in cultured NAc neurons. We found that CART attenuated the caffeine-mediated enhancement of depolarization-induced Ca2+ influx and CaMKIIα phosphorylation in cultured NAc neurons. Repeated microinjection of CART peptides into the NAc decreased the caffeine-induced enhancement of Ca2+ channels activity, pCaMKIIα levels, the pCaMKIIα-D3R interaction, D3R phosphorylation, cAMP levels, PKA activity and pCREB levels in the NAc. Furthermore, behavioral sensitization was observed in rats that received five-day administration of caffeine following microinjection of saline but not in rats that were treated with caffeine following microinjection of CART peptide. These results suggest that caffeine-induced CREB phosphorylation in the NAc was ameliorated by CART peptide due to its inhibition of D3R phosphorylation. These effects of CART peptides may play a compensatory role by inhibiting locomotor behavior in rats.
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Affiliation(s)
- Qiang Fu
- Department of Respiration, The Fourth Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China
- Department of Respiration, Department Two, Jiangxi Provincial People’s Hospital, Nanchang, Jiangxi, China
| | - Xiaoyan Zhou
- Department of Pathophysiology, College of Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Yun Dong
- Department of Breast Surgery, Jiangxi Tumor Hospital, Nanchang, Jiangxi, China
| | - Yonghong Huang
- Department of Pathophysiology, College of Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Jianhua Yang
- Department of Physiology, College of Medicine, Nanchang University, Nanchang, Jiangxi, China
| | - Ki-Wan Oh
- College of Pharmacy, Chungbuk National University, Cheongju, Republic of Korea
| | - Zhenzhen Hu
- Department of Pathophysiology, College of Medicine, Nanchang University, Nanchang, Jiangxi, China
- * E-mail: ;
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Bakhtazad A, Vousooghi N, Garmabi B, Zarrindast MR. CART peptide and opioid addiction: Expression changes in male rat brain. Neuroscience 2016; 325:63-73. [PMID: 26955782 DOI: 10.1016/j.neuroscience.2016.02.071] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 02/09/2016] [Accepted: 02/29/2016] [Indexed: 01/21/2023]
Abstract
Previous studies have shown the prominence of cocaine- and amphetamine-regulated transcript (CART) peptide in rewarding and reinforcing effects of drugs of abuse specially psychostimulants. The data regarding the effects of different stages of opioid addiction on CART expression and the interconnection between CART and opioids are not much available. Here we have studied the changes in the expression level of CART mRNA and protein in various parts of the brain reward pathway in different stages of opioid addiction. Groups of male rats received acute low-dose (10mg/kg), acute high-dose (80mg/kg) and chronic escalating doses of morphine. In addition, withdrawal and abstinence states were evaluated after injection of naloxone (1mg/kg) and long-term maintenance of addicted animals, respectively. Expression of CART mRNA in the brain was measured by real-time PCR method. Western blotting was used to quantify the protein level. CART mRNA and protein were both up-regulated in high-dose morphine-administered animals and also in the withdrawal group in the nucleus accumbens (NAc), striatum and prefrontal cortex (PFC). In the addicted group, CART mRNA and protein were both down-regulated in NAc and striatum. In the abstinent group, CART mRNA was down-regulated in NAc. In the hippocampus, the only observed change was the up-regulation of CART mRNA in the withdrawal group. We suggest that the modulatory role of CART peptide in rewarding and reinforcing effects of opioids weakens when opioids are used for a long time and is stimulated when acute stress such as naloxone-induced withdrawal syndrome or acute high-dose administration of morphine occurs to the animal.
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Affiliation(s)
- A Bakhtazad
- Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - N Vousooghi
- Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Genetics Laboratory, Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran
| | - B Garmabi
- Department of Neuroscience, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - M R Zarrindast
- Genetics Laboratory, Iranian National Center for Addiction Studies (INCAS), Iranian Institute for Reduction of High-Risk Behaviors, Tehran University of Medical Sciences, Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies, Tehran, Iran; Genomics Center, School of Advanced Sciences, Tehran Medical Branch, Islamic Azad University, Tehran, Iran; School of Cognitive Sciences, Institute for Studies in Theoretical Physics and Mathematics, Tehran, Iran.
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Cho JH, Cho YH, Kim HY, Cha SH, Ryu H, Jang W, Shin KH. Increase in cocaine- and amphetamine-regulated transcript (CART) in specific areas of the mouse brain by acute caffeine administration. Neuropeptides 2015; 50:1-7. [PMID: 25820086 DOI: 10.1016/j.npep.2015.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 02/10/2015] [Accepted: 03/02/2015] [Indexed: 12/12/2022]
Abstract
Caffeine produces a variety of behavioral effects including increased alertness, reduced food intake, anxiogenic effects, and dependence upon repeated exposure. Although many of the effects of caffeine are mediated by its ability to block adenosine receptors, it is possible that other neural substrates, such as cocaine- and amphetamine-regulated transcript (CART), may be involved in the effects of caffeine. Indeed, a recent study demonstrated that repeated caffeine administration increases CART in the mouse striatum. However, it is not clear whether acute caffeine administration alters CART in other areas of the brain. To explore this possibility, we investigated the dose- and time-dependent changes in CART immunoreactivity (CART-IR) after a single dose of caffeine in mice. We found that a high dose of caffeine (100 mg/kg) significantly increased CART-IR 2 h after administration in the nucleus accumbens shell (AcbSh), dorsal bed nucleus of the stria terminalis (dBNST), central nucleus of the amygdala (CeA), paraventricular hypothalamic nucleus (PVN), arcuate hypothalamic nucleus (Arc), and locus coeruleus (LC), and returned to control levels after 8 h. But this increase was not observed in other brain areas. In addition, caffeine administration at doses of 25 and 50 mg/kg appears to produce dose-dependent increases in CART-IR in these brain areas; however, the magnitude of increase in CART-IR observed at a dose of 50 mg/kg was similar or greater than that observed at a dose of 100 mg/kg. This result suggests that CART-IR in AcbSh, dBNST, CeA, PVN, Arc, and LC is selectively affected by caffeine administration.
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Affiliation(s)
- Jin Hee Cho
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea
| | - Yun Ha Cho
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea
| | - Hyo Young Kim
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea
| | - Seung Ha Cha
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea
| | - Hyun Ryu
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea
| | - Wooyoung Jang
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea
| | - Kyung Ho Shin
- Department of Pharmacology, Korea University College of Medicine, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
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Hu Z, Oh EH, Chung YB, Hong JT, Oh KW. Predominant D1 Receptors Involvement in the Over-expression of CART Peptides after Repeated Cocaine Administration. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2015; 19:89-97. [PMID: 25729269 PMCID: PMC4342741 DOI: 10.4196/kjpp.2015.19.2.89] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 11/18/2014] [Accepted: 12/05/2014] [Indexed: 11/30/2022]
Abstract
The aim of this study was to investigate the involvement of dopaminergic receptors (DR) in behavioral sensitization, as measured by locomotor activity, and the over-expression of cocaine- and amphetamine-regulated transcript (CART) peptides after repeated administration of cocaine in mice. Repeated administrations of cocaine induced behavioral sensitization and CART over-expression in mice. The levels of striatal CART mRNA were significantly increased on the 3rd day. CART peptides were over-expressed on the 5th day in the striata of behaviorally sensitized mice. A higher proportion of CART+ cells in the cocaine-treated mice were present in the nucleus accumbens (NAc) shell than in the dorsolateral (DL) part of caudate putamen (CP). The concomitant administration of both D1R and D2R antagonists, SCH 23390 (D1R selective) and raclopride (D2R selective), blocked cocaine induced-behavioral sensitization, CART over-expression, and cyclic adenosine 5'-monophosphate (cAMP)/protein kinase A (PKA)/phospho-cAMP response element-binding protein (pCREB) signal pathways. SCH 23390 more predominantly inhibited the locomotor activity, CART over-expression, pCREB and PKA activity than raclopride. Cocaine induced-behavioral sensitization was also attenuated in the both D1R and D2R knockout (KO) mice, respectively. CART over-expression and activated cAMP/PKA/pCREB signal pathways were inhibited in the D1R-KO mice, but not in the D2R-KO mice. It is suggested that behavioral sensitization, CART over-expression and activated cAMP/PKA/pCREB signal pathways induced by repeated administration of cocaine could be more predominantly mediated by D1R.
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Affiliation(s)
- Zhenzhen Hu
- Department of Pathophysiology, College of Medicine, Nanchang University, Jiangxi 330006, China
| | - Eun-Hye Oh
- Department of Pharmacy, College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
| | - Yeon Bok Chung
- Department of Pharmacy, College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
| | - Jin Tae Hong
- Department of Pharmacy, College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
| | - Ki-Wan Oh
- Department of Pharmacy, College of Pharmacy, Chungbuk National University, Cheongju 361-763, Korea
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Caffeine induces behavioural sensitization and overexpression of cocaine-regulated and amphetamine-regulated transcript peptides in mice. Behav Pharmacol 2014; 25:32-43. [PMID: 24366314 DOI: 10.1097/fbp.0000000000000016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
This study examined whether repeated administration of caffeine would induce behavioural sensitization and overexpression of cocaine-regulated and amphetamine-regulated transcript (CART) peptides in mice. The involvement of dopaminergic receptors and adenosine receptors in caffeine-induced behavioural sensitization and CART overexpression was studied. The relevance of D₁R and D₂R, and A₁R and A(2A)R in the overexpression of CART peptides in mouse striatum was also evaluated. Repeated administration of caffeine induced behavioural sensitization in mice. Significant increases in CART mRNA levels were observed on day 3 and peaked at day 5 of caffeine administration, and then decreased gradually. Higher proportions of CART⁺ cells were observed in the dorsolateral and ventrolateral part of the caudate putamen than in the nucleus accumbens shell and core. The behavioural sensitization induced by caffeine was inhibited by dopaminergic receptor antagonists and adenosine receptor agonists. D₁R and D₂R, and cyclic AMP (cAMP)/protein kinase A (PKA)/phospho-cAMP response element-binding protein (pCREB) signalling were activated by caffeine, but A₁R and A(2A)R were inhibited. Overexpression of caffeine-induced CART peptides and pCREB activity were blocked by N-cyclopentyladenosine (CPA, an A₁R agonist) and 4-[2-[[6-amino-9-(N-ethyl-β-D-ribofuranuronamidosyl)-9H-purin-2-yl]amino]ethyl]benzenepropanoic acid hydrochloride (CGS 21680, an A(2A)R agonist), but not by R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride (SCH 23390, a D₁R antagonist) or raclopride (a D₂R antagonist). Caffeine-induced overexpression of CART peptides was associated with the inhibition of A₁R and A(2A)R, and the activation of cAMP/PKA/pCREB signalling. Moreover, the A(2A)R-D₂R heterodimer might be involved in the overexpression of CART peptides induced by caffeine.
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Peng Q, Sun X, Liu Z, Yang J, Oh KW, Hu Z. Microinjection of CART (cocaine- and amphetamine-regulated transcript) peptide into the nucleus accumbens inhibits the cocaine-induced upregulation of dopamine receptors and locomotor sensitization. Neurochem Int 2014; 75:105-11. [PMID: 24953280 DOI: 10.1016/j.neuint.2014.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/06/2014] [Accepted: 06/10/2014] [Indexed: 11/15/2022]
Abstract
Repeated exposure to addictive drugs enhances dopamine receptor (DR) signaling and the ultimate phosphorylation of the cyclic adenosine 5'-monophosphate (cAMP)-response element-binding protein (CREB)-regulated cocaine- and amphetamine-regulated transcript (CART) expression in the nucleus accumbens (NAcc). These effects are known to contribute to the expression of behavioral sensitization. CART peptides are neuropeptides that modulate drug reward and reinforcement. The present experiments investigated the effects of CART 55-102 microinjection into the NAcc on (1) the phosphorylation of CREB, (2) cAMP/protein kinase A (PKA) signaling and (3) extracellular signal-regulated kinase (ERK) phosphorylated kinase signaling. Here, we show that repeated microinjections into the NAcc of CART 55-102 peptides (1.0 or 2.5μg, 0.5μl/side) attenuates cocaine-induced enhancements of D1R, D2R and D3R phosphorylation in this sites. Furthermore, the microinjection of CART 55-102 followed by repeated injections of cocaine (15mg/kg) dose-dependently blocked the enhancement of cAMP levels, PKA activity and pERK and pCREB levels on the fifth day of cocaine administration. The cocaine-induced locomotor activity and behavioral sensitization in rats were also inhibited by the 5-day-microinjection of CART peptides. These results suggest that the phosphorylation of CREB by cocaine in the NAcc was blocked by the CART 55-102 peptide via the inhibition of D1R and D2R stimulation, D3R phosphorylation, cAMP/PKA signaling and ERK phosphorylated kinase signaling. These effects may have played a compensatory inhibitory role in the behavioral sensitization of rats that received microinjections of CART 55-102.
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Affiliation(s)
- Qinghua Peng
- Department of Anesthesiology, The First Affiliated Hospital, Nanchang University, Nanchang, Jiangxi 33006, China
| | - Xi Sun
- Evidence Identification Center, Department of Jiangxi Provincial Public Security, Nanchang, Jiangxi 33006, China
| | - Ziyong Liu
- Department of Physiology, College of Medicine, Nanchang University, Nanchang, Jiangxi 33006, China
| | - Jianghua Yang
- Evidence Identification Center, Department of Jiangxi Provincial Public Security, Nanchang, Jiangxi 33006, China
| | - Ki-Wan Oh
- College of Pharmacy, Chungbuk National University, Cheongju 361-763, Republic of Korea
| | - Zhenzhen Hu
- Department of Pathophysiology, College of Medicine, Nanchang University, Nanchang, Jiangxi 33006, China.
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Subhedar NK, Nakhate KT, Upadhya MA, Kokare DM. CART in the brain of vertebrates: circuits, functions and evolution. Peptides 2014; 54:108-30. [PMID: 24468550 DOI: 10.1016/j.peptides.2014.01.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 01/10/2014] [Accepted: 01/10/2014] [Indexed: 12/12/2022]
Abstract
Cocaine- and amphetamine-regulated transcript peptide (CART) with its wide distribution in the brain of mammals has been the focus of considerable research in recent years. Last two decades have witnessed a steady rise in the information on the genes that encode this neuropeptide and regulation of its transcription and translation. CART is highly enriched in the hypothalamic nuclei and its relevance to energy homeostasis and neuroendocrine control has been understood in great details. However, the occurrence of this peptide in a range of diverse circuitries for sensory, motor, vegetative, limbic and higher cortical areas has been confounding. Evidence that CART peptide may have role in addiction, pain, reward, learning and memory, cognition, sleep, reproduction and development, modulation of behavior and regulation of autonomic nervous system are accumulating, but an integration has been missing. A steady stream of papers has been pointing at the therapeutic potentials of CART. The current review is an attempt at piecing together the fragments of available information, and seeks meaning out of the CART elements in their anatomical niche. We try to put together the CART containing neuronal circuitries that have been conclusively demonstrated as well as those which have been proposed, but need confirmation. With a view to finding out the evolutionary antecedents, we visit the CART systems in sub-mammalian vertebrates and seek the answer why the system is shaped the way it is. We enquire into the conservation of the CART system and appreciate its functional diversity across the phyla.
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Affiliation(s)
- Nishikant K Subhedar
- Indian Institute of Science Education and Research (IISER), Sai Trinity Building, Sutarwadi, Pashan, Pune 411 021, Maharashtra, India.
| | - Kartik T Nakhate
- Rungta College of Pharmaceutical Sciences and Research, Rungta Educational Campus, Kohka-Kurud Road, Bhilai 490 024, Chhattisgarh, India
| | - Manoj A Upadhya
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India
| | - Dadasaheb M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India
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Lee JS, Lee HS. Reciprocal connections between CART-immunoreactive, hypothalamic paraventricular neurons and serotonergic dorsal raphe cells in the rat: Light microscopic study. Brain Res 2014; 1560:46-59. [DOI: 10.1016/j.brainres.2014.03.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/13/2014] [Accepted: 03/07/2014] [Indexed: 10/25/2022]
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18
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Assessing addiction vulnerability with different rat strains and place preference procedures. Behav Pharmacol 2013; 24:471-7. [DOI: 10.1097/fbp.0b013e328364160a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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19
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Sathanoori R, Olde B, Erlinge D, Göransson O, Wierup N. Cocaine- and amphetamine-regulated transcript (CART) protects beta cells against glucotoxicity and increases cell proliferation. J Biol Chem 2012; 288:3208-18. [PMID: 23250745 DOI: 10.1074/jbc.m112.437145] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cocaine- and amphetamine-regulated transcript (CART) is an islet peptide that promotes glucose-stimulated insulin secretion in beta cells via cAMP/PKA-dependent pathways. In addition, CART is a regulator of neuronal survival. In this study, we examined the effect of exogenous CART 55-102 on beta cell viability and dissected its signaling mechanisms. Evaluation of DNA fragmentation and chromatin condensation revealed that CART 55-102 reduced glucotoxicity-induced apoptosis in both INS-1 (832/13) cells and isolated rat islets. Glucotoxicity in INS-1 (832/13) cells also caused a 50% reduction of endogenous CART protein. We show that CART increased proliferation in INS-1 (832/13) cells, an effect that was blocked by PKA, PKB, and MEK1 inhibitors. In addition, CART induced phosphorylation of CREB, IRS, PKB, FoxO1, p44/42 MAPK, and p90RSK in INS-1 (832/13) cells and isolated rat islets, all key mediators of cell survival and proliferation. Thus, we demonstrate that CART 55-102 protects beta cells against glucotoxicity and promotes proliferation. Taken together our data point to the potential use of CART in therapeutic interventions targeted at enhancing functional beta cell mass and long-term insulin secretion in T2D.
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Zhang J, Wang S, Yuan L, Yang Y, Zhang B, Liu Q, Chen L, Yue W, Li Y, Pei X. Neuron-restrictive silencer factor (NRSF) represses cocaine- and amphetamine-regulated transcript (CART) transcription and antagonizes cAMP-response element-binding protein signaling through a dual NRSE mechanism. J Biol Chem 2012; 287:42574-87. [PMID: 23086924 DOI: 10.1074/jbc.m112.376590] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cocaine- and amphetamine-regulated transcript (CART) peptide plays a pivotal role in neuroprotection against stroke-related brain injury. However, the regulatory mechanism on CART transcription, especially the repression mechanism, is not fully understood. Here, we show that the transcriptional repressor neuron-restrictive silencer elements (NRSF, also known as REST) represses CART expression through direct binding to two NRSF-binding elements (NRSEs) in the CART promoter and intron 1 (named pNRSE and iNRSE, respectively). EMSA show that NRSF binds to pNRSE and iNRSE directly in vitro. ChIP assays show that NRSF recruits differential co-repressor complexes including CoREST and HDAC1 to these NRSEs. The presence of both NRSEs is required for efficient repression of CART transcription as indicated by reporter gene assays. NRSF overexpression antagonizes forskolin-mediated up-regulation of CART mRNA and protein. Ischemia insult triggered by oxygen-glucose deprivation (OGD) enhances NRSF mRNA levels and then NRSF antagonizes the CREB signaling on CART activation, leading to augmented cell death. Depletion of NRSF in combination with forskolin treatment increases neuronal survival after ischemic insult. These findings reveal a novel dual NRSE mechanism by which NRSF represses CART expression and suggest that NRSF may serve as a therapeutic target for stroke treatment.
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Affiliation(s)
- Jing Zhang
- Stem Cell and Regenerative Medicine Laboratory, Beijing Institute of Transfusion Medicine, Beijing 100850, China
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Region- and sex-specific changes in CART mRNA in rat hypothalamic nuclei induced by forced swim stress. Brain Res 2012; 1479:62-71. [PMID: 22960117 DOI: 10.1016/j.brainres.2012.08.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Revised: 08/23/2012] [Accepted: 08/24/2012] [Indexed: 01/22/2023]
Abstract
Cocaine and amphetamine regulated transcript (CART) mRNA and peptides are highly expressed in the paraventricular (PVN), dorsomedial (DMH) and arcuate (ARC) nuclei of the hypothalamus. It has been suggested that these nuclei regulate the hypothalamic-pituitary-adrenal (HPA) axis, autonomic nervous system activity, and feeding behavior. Our previous studies showed that forced swim stress augmented CART peptide expression significantly in whole hypothalamus of male rats. In another study, forced swim stress increased the number of CART-immunoreactive cells in female PVN, whereas no effect was observed in male PVN or in the ARC nucleus of either sex. In the present study, we evaluated the effect of forced swim stress on CART mRNA expression in PVN, DMH and ARC nuclei in both male and female rats. Twelve male (stressed and controls, n=6 each) and 12 female (stressed and controls, n=6 each) Sprague-Dawley rats were used. Control animals were only handled, whereas forced swim stress procedure was applied to the stressed groups. Brains were dissected and brain sections containing PVN, DMH and ARC nuclei were prepared. CART mRNA levels were determined by in situ hybridization. In male rats, forced swim stress upregulated CART mRNA expression in DMH and downregulated it in the ARC. In female rats, forced swim stress increased CART mRNA expression in PVN and DMH, whereas a decrease was observed in the ARC nucleus. Our results show that forced swim stress elicits region- and sex-specific changes in CART mRNA expression in rat hypothalamus that may help in explaining some of the effects of stress.
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Rogge GA, Shen LL, Kuhar MJ. Chromatin immunoprecipitation assays revealed CREB and serine 133 phospho-CREB binding to the CART gene proximal promoter. Brain Res 2010; 1344:1-12. [PMID: 20451507 DOI: 10.1016/j.brainres.2010.04.069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 04/14/2010] [Accepted: 04/26/2010] [Indexed: 02/07/2023]
Abstract
Both over expression of cyclic AMP response element binding protein (CREB) in the nucleus accumbens (NAc), and intra-accumbal injection of cocaine- and amphetamine-regulated transcript (CART) peptides, have been shown to decrease cocaine reward. Also, over expression of CREB in the rat NAc increased CART mRNA and peptide levels, but it is not known if this was due to a direct action of P-CREB on the CART gene promoter. The goal of this study was to test if CREB and P-CREB bound directly to the CRE site in the CART promoter, using chromatin immunoprecipitation (ChIP) assays. ChIP assay with anti-CREB antibodies showed an enrichment of the CART promoter fragment containing the CRE region over IgG precipitated material, a non-specific control. Forskolin, which was known to increase CART mRNA levels in GH3 cells, was utilized to show that the drug increased levels of P-CREB protein and P-CREB binding to the CART promoter CRE-containing region. A region of the c-Fos promoter containing a CRE cis-regulatory element was previously shown to bind P-CREB, and it was used here as a positive control. These data suggest that the effects of CREB over expression on blunting cocaine reward could be, at least in part, attributed to the increased expression of the CART gene by direct interaction of P-CREB with the CART promoter CRE site, rather than by some indirect action.
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Affiliation(s)
- George A Rogge
- Yerkes National Research Primate Center of Emory University, Atlanta, GA 30329, USA
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Kuhar MJ. Measuring levels of proteins by various technologies: can we learn more by measuring turnover? Biochem Pharmacol 2009; 79:665-8. [PMID: 19814998 DOI: 10.1016/j.bcp.2009.09.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 09/29/2009] [Accepted: 09/30/2009] [Indexed: 12/01/2022]
Abstract
In routine experiments, scientists measure the levels of various substances such as proteins after various treatments. Detection of a change in levels suggests an impact of treatment on that particular protein. However, we sometimes forget the importance of turnover in this process. Proteins have half-lives that may change in response to treatments (which is in fact why levels may change), and an examination of half-lives may yield better clues as to how treatment affects the protein. After an exploration of the quantitative aspects of protein turnover, several interesting conclusions may be drawn. (1) Even though levels of some proteins may NOT change after treatments, their half-lives and turnovers do change, and these may be more sensitive indicators of the impact of treatments on the proteins of interest. (2) Treatments can affect protein levels because they alter either the synthesis or degradation of the protein or both. But, the rate of change of the levels depends on the half-life of the protein. If the experimenter waits only a fraction of a half-life of the protein after treatment, no significant change in level may be found since it can take up to 5 half-lives for the protein level to adjust to about 97% of its new level after treatment. (3) Half-lives of the same protein can vary in different species and experimental conditions may have to be altered if using different species. These factors suggest that a consideration of protein turnover and half-lives will be useful for future studies of this type.
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Affiliation(s)
- Michael J Kuhar
- Yerkes National Primate Research Center of Emory University, 954 Gatewood Rd NE, Atlanta, GA 30329, USA.
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Dandekar MP, Singru PS, Kokare DM, Subhedar NK. Cocaine- and amphetamine-regulated transcript peptide plays a role in the manifestation of depression: social isolation and olfactory bulbectomy models reveal unifying principles. Neuropsychopharmacology 2009; 34:1288-300. [PMID: 19005467 DOI: 10.1038/npp.2008.201] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We investigated the effect of cocaine- and amphetamine-regulated transcript (CART) peptide on depression-like behavior in socially isolated and olfactory bulbectomized (OBX) rats. Administration of CART (54-102) into the lateral ventricle (50-100 ng) or central nucleus of amygdala (CeA) (10-20 ng) caused significant decrease in immobility time in the forced swim test (FST) without influencing locomotion, suggesting antidepressant-like effect. Social isolation as well as OBX models were undertaken to produce depression-like conditions. Although isolation reared (6 weeks) rats showed significant increase in immobility time in FST, OBX animals exhibited hyperactivity (increase in the ambulation, rearing, grooming, and defecation scores) on day 14 in the open-field test. The isolation- or OBX-induced depression-like phenotypes were reversed following acute or subchronic treatment of CART, respectively, given via intracerebroventricular and intra-CeA routes. Drastic reduction in CART-immunoreactivity was observed in most cells in the paraventricular (PVN), arcuate and Edinger-Westphal nuclei of the socially isolated and OBX animals. Although the fibers in the PVN showed variable response, those in ARC and prefrontal cortex did not change. The CART-immunoreactive fibers in the locus coeruleus also showed highly significant reduction. However, dramatic increase in CART-immunoreactive fibers was noticed in the CeA in both the experimental models. The response by the cells and fibers in the periventricular area and perifornical nucleus in the OBX and socially isolated rats was variable. The study underscores the possibility that endogenous CART system might play a major role in mediating symptoms of depression.
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Affiliation(s)
- Manoj P Dandekar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University Campus, Nagpur, India
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Jones DC, Lakatos A, Rogge GA, Kuhar MJ. Regulation of cocaine- and amphetamine-regulated transcript mRNA expression by calcium-mediated signaling in GH3 cells. Neuroscience 2009; 160:339-47. [PMID: 19258027 DOI: 10.1016/j.neuroscience.2009.02.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 02/20/2009] [Accepted: 02/23/2009] [Indexed: 11/28/2022]
Abstract
Cocaine- and amphetamine-regulated-transcript (CART) peptides are associated with multiple physiological processes, including, feeding, body weight, and the response to drugs of abuse. CART mRNA and peptide levels and the expression of the CART gene appears to be under the control of a number of extra- and intra-cellular factors including the transcription factor, cAMP response element binding protein (CREB). Similar to the effects of CART, Ca(2+) signaling leads to the phosphorylation of CREB and has been associated with both feeding and the actions of psychostimulants; therefore, we hypothesized that Ca(2+) may play a role in CART gene regulation. We used real-time PCR (rtPCR) and GH3 cells to examine the effect of ionomycin, which increases intracellular Ca(2+), on CART mRNA levels. Ionomycin increased CART mRNA in a dose- and time-dependent manner. The effect of ionomycin appeared transient as CART mRNA had returned to control levels 3 h following treatment. Calmidazolium and KN93, inhibitors of calmodulin and Ca(2+)-modulated protein (CaM) kinases respectively, attenuated the effect of ionomycin (10 microM) on CART mRNA levels suggesting a calmodulin-dependent mechanism. Western immunoblotting indicated that ionomycin increased phosphorylated cAMP response element binding protein (pCREB) levels and electrophoretic mobility shift assay/supershift assay using antibodies against pCREB demonstrated increased levels of a CART oligo/pCREB protein complex. Finally, we showed that injection of ionomycin into the rat nucleus accumbens increases CART mRNA levels. To our knowledge, this is the first study providing evidence that the CART gene is, in part, regulated by Ca(2+)/CaM/CREB-dependent cell signaling.
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Affiliation(s)
- D C Jones
- Division of Neuroscience, Yerkes National Primate Research Center of Emory University, 945 Gatewood Road, Atlanta, GA 30329, USA.
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Regulation of CART peptide expression by CREB in the rat nucleus accumbens in vivo. Brain Res 2008; 1251:42-52. [PMID: 19046951 DOI: 10.1016/j.brainres.2008.11.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 10/22/2008] [Accepted: 11/01/2008] [Indexed: 11/20/2022]
Abstract
Production of mRNA from the cocaine- and amphetamine-regulated transcript (CART) gene is regulated by cocaine and other drugs of abuse in the nucleus accumbens (NAc), a brain reward region. Current hypotheses postulate that CART peptides there oppose the rewarding actions of cocaine by opposing the effects of dopaminergic transmission. Since over expression of CREB was shown to decrease cocaine-mediated reward, we hypothesized that CART could be a target gene for CREB in the NAc and that over expression of CREB would increase CART peptide levels. Transcription factor (TF) binding to DNA is influenced by sequences adjacent to consensus TF binding sites and other factors. We thus examined CREB binding to a 27mer oligonucleotide containing the CRE sequence from the CART gene proximal promoter. Using electrophoretic mobility shift assays and TF-antibody super shift assays, CREB was found to bind to the CRE sequence from the CART promoter. To test if over expression of CREB in the NAc affected CART peptide levels, Herpes simplex virus-1 vectors over expressing CREB (HSV-CREB), or a vector that expressed LacZ (HSV-LacZ) as a control, were injected into the NAc of rats. Western blotting and in situ hybridization showed that HSV-CREB injections increased CART mRNA and peptide levels. Injections of a dominant negative CREB mutant (HSV-mCREB) did not alter either CART mRNA or peptide levels. The finding that CREB can regulate the levels of CART mRNA and peptides in vivo in the NAc supports a role for CART peptides in psychostimulant-induced reward and reinforcement.
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Quantitative trait locus analysis identifies rat genomic regions related to amphetamine-induced locomotion and Galpha(i3) levels in nucleus accumbens. Neuropsychopharmacology 2008; 33:2735-46. [PMID: 18216777 PMCID: PMC2818767 DOI: 10.1038/sj.npp.1301667] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Identification of the genetic factors that underlie stimulant responsiveness in animal models has significant implications for better understanding and treating stimulant addiction in humans. F(2) progeny derived from parental rat strains F344/NHsd and LEW/NHsd, which differ in responses to drugs of abuse, were used in quantitative trait locus (QTL) analyses to identify genomic regions associated with amphetamine-induced locomotion (AIL) and G-protein levels in the nucleus accumbens (NAc). The most robust QTLs were observed on chromosome 3 (maximal log ratio statistic score (LRS(max))=21.3) for AIL and on chromosome 2 (LRS(max)=22.0) for Galpha(i3). A 'suggestive' QTL (LRS(max)=12.5) was observed for AIL in a region of chromosome 2 that overlaps with the Galpha(i3) QTL. Novelty-induced locomotion (NIL) showed different QTL patterns from AIL, with the most robust QTL on chromosome 13 (LRS(max)=12.2). Specific unique and overlapping genomic regions influence AIL, NIL, and inhibitory G-protein levels in the NAc. These findings suggest that common genetic mechanisms influence certain biochemical and behavioral aspects of stimulant responsiveness.
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Rogge G, Jones D, Hubert GW, Lin Y, Kuhar MJ. CART peptides: regulators of body weight, reward and other functions. Nat Rev Neurosci 2008; 9:747-58. [PMID: 18802445 PMCID: PMC4418456 DOI: 10.1038/nrn2493] [Citation(s) in RCA: 234] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Over the past decade or so, CART (cocaine- and amphetamine-regulated transcript) peptides have emerged as major neurotransmitters and hormones. CART peptides are widely distributed in the CNS and are involved in regulating many processes, including food intake and the maintenance of body weight, reward and endocrine functions. Recent studies have produced a wealth of information about the location, regulation, processing and functions of CART peptides, but additional studies aimed at elucidating the physiological effects of the peptides and at characterizing the CART receptor(s) are needed to take advantage of possible therapeutic applications.
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Affiliation(s)
- G Rogge
- Neuroscience Division, Yerkes National Primate Research Center of Emory University, 954 Gatewood Road NE, Atlanta, Georgia 30329, USA
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Transient up-regulation of cocaine- and amphetamine-regulated transcript peptide (CART) immunoreactivity following ethanol withdrawal in rat hypothalamus. Brain Res 2008; 1240:119-31. [PMID: 18823957 DOI: 10.1016/j.brainres.2008.09.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2008] [Revised: 09/02/2008] [Accepted: 09/04/2008] [Indexed: 11/21/2022]
Abstract
We investigated the profile of CART immunoreactivity in some discrete hypothalamic nuclei following chronic ethanol treatment and withdrawal conditions. Adult, male, Sprague-Dawley rats were fed with liquid diet (pair-fed) or liquid diet containing ethanol (ethanol-fed) for 15 days. Thereafter, all the animals were given access to ethanol free nutritionally balanced liquid diet and killed at 0, 24, 48 and 72 h post-withdrawal, and their brains processed for immunocytochemistry using monoclonal antibodies against CART. CART-immunoreactive fibers, but not the cells, were significantly increased in the paraventricular nucleus (PVN). However, the profile of CART-immunoreactive cells and/or fibers in the periventricular area (PeA), arcuate nucleus (ARC), perifornical area inclusive of lateral hypothalamus (LH) and tuber cinereum (TC), dorsomedial (DMH), and ventromedial (VMH) hypothalamus at the 0 h ethanol withdrawal time point was quite similar to that in the pair-fed control rats. Twenty-four hours following ethanol withdrawal, the immunoreactivity in all these areas was dramatically increased. While significant reduction in CART immunoreactivity was noticed in the PVN, PeA, ARC and VMH at 48 h, immunoreactive profile was restored to normal by 72 h post-ethanol withdrawal. The immunoreactive profile in the LH, TC and DMH resembled that of the pair-fed groups at 48 and 72 h post-withdrawal intervals. However, CART-immunoreactive profile in the supraoptic nucleus did not respond to the chronic ethanol treatment and/or withdrawal. We suggest that transient up-regulation of CART in some discrete hypothalamic nuclei following ethanol withdrawal, at least in part, may contribute to the pathogenesis of ethanol withdrawal-induced symptoms like anxiety and anorexia.
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Hubert GW, Kuhar MJ. Cocaine administration increases the fraction of CART cells in the rat nucleus accumbens that co-immunostain for c-Fos. Neuropeptides 2008; 42:339-43. [PMID: 18314190 PMCID: PMC2493299 DOI: 10.1016/j.npep.2008.01.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2007] [Revised: 12/14/2007] [Accepted: 01/12/2008] [Indexed: 11/29/2022]
Abstract
In order to further test whether or not psychostimulant drugs activate CART peptide-containing cells in the nucleus accumbens, we examined the fraction of CART positive cells that co-immunostained for c-Fos after administration of saline or cocaine (10 and 25 mg/kg i.p.). There was about a 45% increase in the fraction of cells that stained for both CART and c-Fos after administration of cocaine, but there was no change in the fraction after administration of saline. Moreover, the increase was not found 24h after injection and is therefore reversible. These results support the notion that psychostimulant drugs activate CART cells in the nucleus accumbens, even under conditions where it is difficult to show a change in CART levels.
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Affiliation(s)
- G W Hubert
- Division of Neuroscience, The National Yerkes Primate Research Center of Emory University, Atlanta, GA 30329, USA.
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31
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Hsieh YS, Yang SF, Chu SC, Ho YJ, Kuo CS, Kuo DY. Transcriptional interruption of cAMP response element binding protein modulates superoxide dismutase and neuropeptide Y-mediated feeding behavior in freely moving rats. J Neurochem 2008; 105:1438-49. [DOI: 10.1111/j.1471-4159.2008.05246.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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32
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Jean A, Conductier G, Manrique C, Bouras C, Berta P, Hen R, Charnay Y, Bockaert J, Compan V. Anorexia induced by activation of serotonin 5-HT4 receptors is mediated by increases in CART in the nucleus accumbens. Proc Natl Acad Sci U S A 2007; 104:16335-40. [PMID: 17913892 PMCID: PMC2042207 DOI: 10.1073/pnas.0701471104] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Anorexia nervosa is a growing concern in mental health, often inducing death. The potential neuronal deficits that may underlie abnormal inhibitions of food intake, however, remain largely unexplored. We hypothesized that anorexia may involve altered signaling events within the nucleus accumbens (NAc), a brain structure involved in reward. We show here that direct stimulation of serotonin (5-hydroxytryptamine, 5-HT) 4 receptors (5-HT(4)R) in the NAc reduces the physiological drive to eat and increases CART (cocaine- and amphetamine-regulated transcript) mRNA levels in fed and food-deprived mice. It further shows that injecting 5-HT(4)R antagonist or siRNA-mediated 5-HT(4)R knockdown into the NAc induced hyperphagia only in fed mice. This hyperphagia was not associated with changes in CART mRNA expression in the NAc in fed and food-deprived mice. Results include that 5-HT(4)R control CART mRNA expression into the NAc via a cAMP/PKA signaling pathway. Considering that CART may interfere with food- and drug-related rewards, we tested whether the appetite suppressant properties of 3,4-N-methylenedioxymethamphetamine (MDMA, ecstasy) involve the 5-HT(4)R. Using 5-HT(4)R knockout mice, we demonstrate that 5-HT(4)R are required for the anorectic effect of MDMA as well as for the MDMA-induced enhancement of CART mRNA expression in the NAc. Directly injecting CART peptide or CART siRNA into the NAc reduces or increases food consumption, respectively. Finally, stimulating 5-HT(4)R- and MDMA-induced anorexia were both reduced by injecting CART siRNA into the NAc. Collectively, these results demonstrate that 5-HT(4)R-mediated up-regulation of CART in the NAc triggers the appetite-suppressant effects of ecstasy.
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MESH Headings
- Animals
- Anorexia Nervosa/etiology
- Anorexia Nervosa/genetics
- Anorexia Nervosa/metabolism
- Base Sequence
- Eating
- Male
- Mice
- Mice, Knockout
- N-Methyl-3,4-methylenedioxyamphetamine/pharmacology
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Nucleus Accumbens/drug effects
- Nucleus Accumbens/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/genetics
- Receptors, Serotonin, 5-HT4/deficiency
- Receptors, Serotonin, 5-HT4/genetics
- Receptors, Serotonin, 5-HT4/metabolism
- Signal Transduction
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Affiliation(s)
- Alexandra Jean
- *Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR)5203, Institut National de la Santé et de la Recherche Médicale, U661, Université Montpellier I and II, Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
- Université Nîmes (JE2425, Team 1, Anorexie, Dépendance, Obésité de Nîmes: ADONîmes), Rue Docteur Georges Salan, F-30021 Nîmes, France
| | - Grégory Conductier
- *Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR)5203, Institut National de la Santé et de la Recherche Médicale, U661, Université Montpellier I and II, Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
- Université Nîmes (JE2425, Team 1, Anorexie, Dépendance, Obésité de Nîmes: ADONîmes), Rue Docteur Georges Salan, F-30021 Nîmes, France
| | - Christine Manrique
- CNRS, UMR6149, Université Aix-Marseille I, Neurobiologie Intégrative et Adaptative, 3 Place Victor Hugo, F-13331 Marseille Cedex 3, France
| | - Constantin Bouras
- Hôpitaux Universitaires de Genève, Division de Neuropsychiatrie, CH-1225 Chêne-bourg, Switzerland; and
| | - Philippe Berta
- Université Nîmes (JE2425, Team 1, Anorexie, Dépendance, Obésité de Nîmes: ADONîmes), Rue Docteur Georges Salan, F-30021 Nîmes, France
| | - René Hen
- Center of Neurobiology and Behavior, Columbia University, New York, NY 10032
| | - Yves Charnay
- Hôpitaux Universitaires de Genève, Division de Neuropsychiatrie, CH-1225 Chêne-bourg, Switzerland; and
| | - Joël Bockaert
- *Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR)5203, Institut National de la Santé et de la Recherche Médicale, U661, Université Montpellier I and II, Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
| | - Valérie Compan
- *Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR)5203, Institut National de la Santé et de la Recherche Médicale, U661, Université Montpellier I and II, Institut de Génomique Fonctionnelle, Département de Neurobiologie, 141 Rue de la Cardonille, F-34094 Montpellier Cedex 5, France
- Université Nîmes (JE2425, Team 1, Anorexie, Dépendance, Obésité de Nîmes: ADONîmes), Rue Docteur Georges Salan, F-30021 Nîmes, France
- To whom correspondence should be addressed. E-mail:
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Yoon HS, Kim S, Park HK, Kim JH. Microinjection of CART peptide 55-102 into the nucleus accumbens blocks both the expression of behavioral sensitization and ERK phosphorylation by cocaine. Neuropharmacology 2007; 53:344-51. [PMID: 17610912 DOI: 10.1016/j.neuropharm.2007.05.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 05/17/2007] [Accepted: 05/21/2007] [Indexed: 11/30/2022]
Abstract
The role of the biologically active CART 55-102 peptide in the nucleus accumbens (NAcc) in the expression of cocaine-induced behavioral sensitization was investigated. Rats were divided into four groups: one for saline and the other three for cocaine pre-exposures (15 mg/kg, i.p., once daily for 7 days). After 3 weeks of withdrawal, rats were microinjected into the NAcc either saline or CART 55-102 (1.0, or 2.5 microg/0.5 microl/side) followed by cocaine challenge (10 mg/kg, i.p.). Microinjection into the NAcc of CART 55-102 peptide dose-dependently blocked the expression of locomotor sensitization produced by repeated cocaine pre-exposures. Next, we further examined the effect of CART 55-102 microinjection on extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation levels in the NAcc. Additional four groups of rats were all cocaine pre-exposed and, after 3 weeks of withdrawal, they were either saline or cocaine challenged systemically following microinjection into the NAcc of either saline, CART 55-102 (2.5 microg/0.5 microl/side), or the equivalent mole amount of inactive CART 1-27 peptide. The increase of ERK1/2 phosphorylation levels in the NAcc by cocaine was completely blocked by CART 55-102 microinjection in this site, while it remains unaffected by inactive CART 1-27 peptide. These results suggest that CART 55-102 peptide in the NAcc may play a compensatory inhibitory role in the expression of behavioral sensitization by cocaine and these effects may be mediated by its inhibition of ERK1/2 phosphorylation in this site.
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Affiliation(s)
- Hyung Shin Yoon
- Department of Physiology, Brain Korea 21 Project for Medical Science, Brain Research Institute, Yonsei University College of Medicine, 134 Shinchondong, Seodaemungu, Seoul 120-752, South Korea
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de Lartigue G, Dimaline R, Varro A, Dockray GJ. Cocaine- and amphetamine-regulated transcript: stimulation of expression in rat vagal afferent neurons by cholecystokinin and suppression by ghrelin. J Neurosci 2007; 27:2876-82. [PMID: 17360909 PMCID: PMC6672594 DOI: 10.1523/jneurosci.5508-06.2007] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The neuropeptide transmitter cocaine- and amphetamine-regulated transcript (CART) inhibits food intake and is expressed by both vagal afferent and hypothalamic neurons. Here we report that cholecystokinin (CCK) regulates CART expression in rat vagal afferent neurons. Thus, CART was virtually undetectable after energy restriction for 24 h, but administration of CCK to fasted rats increased CART immunoreactivity, and refeeding of fasted animals promptly increased CART by a mechanism sensitive to a CCK-1 receptor antagonist. In vagal afferent neurons incubated in serum-free medium, CART was virtually undetectable, whereas the orexigenic peptide melanin-concentrating hormone (MCH) was readily detected. The addition of CCK rapidly induced CART expression and downregulated MCH. Using a CART promoter-luciferase reporter vector transfected into cultured vagal afferent neurons, we showed that CCK stimulation of CART transcription was mediated by activation of protein kinase C and cAMP response element-binding protein (CREB). The action of CCK on CART expression was inhibited by the orexigenic peptide ghrelin, through a mechanism that involved exclusion of phosphorylated CREB from the nucleus. Thus, CCK reciprocally regulates expression of CART and MCH within the same vagal afferent neuron; ghrelin inhibits the effect of CCK at least in part through control of the nuclear localization of phosphoCREB, revealing previously unsuspected modulation of gut-brain signals implicated in control of food intake.
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Affiliation(s)
- Guillaume de Lartigue
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Rod Dimaline
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Andrea Varro
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Graham J. Dockray
- Physiological Laboratory, School of Biomedical Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
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35
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Regulation of CART mRNA by stress and corticosteroids in the hippocampus and amygdala. Brain Res 2007; 1152:234-40. [PMID: 17434149 DOI: 10.1016/j.brainres.2007.03.042] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2007] [Revised: 03/13/2007] [Accepted: 03/14/2007] [Indexed: 11/18/2022]
Abstract
CART (Cocaine-Amphetamine-Regulated Transcript) has been shown to be regulated by corticosteroids in the hypothalamus, but its regulation by corticosteroids and stress has not been well examined in the hippocampus or the amygdala. Further, CART has been implicated in the transition to puberty. In this study we examine the effects of acute (30 min) stress on CART mRNA in prepubescent and adult rats. In addition, we examined chronic (21 day x 6 h) restraint stress upon the expression of CART mRNA in the hippocampus and the amygdala and the effects of 7 days of adrenalectomy and corticosteroid replacement upon CART expression in these regions of the adult rat brain. We found an up-regulation of CART mRNA in the central amygdala induced by acute but not chronic stress and an up-regulation in the dentate gyrus induced by chronic but not acute stress. Adrenalectomy reduced CART expression in the dentate gyrus but not the amygdala and this effect was blocked by corticosterone but not RU28,362 or aldosterone replacement, suggesting a synergism of mineralocorticoid and glucocorticoid receptors. Our data establish that CART expression is regulated by stress in a regionally and time specific manner and that CART is regulated by corticosteroid actions in the hippocampus.
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36
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Hubert GW, Kuhar MJ. Colocalization of CART peptide with prodynorphin and dopamine D1 receptors in the rat nucleus accumbens. Neuropeptides 2006; 40:409-15. [PMID: 17064765 DOI: 10.1016/j.npep.2006.09.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Revised: 08/01/2006] [Accepted: 09/02/2006] [Indexed: 10/24/2022]
Abstract
CART peptide is a peptidergic neurotransmitter that is expressed in brain regions involved in critical biological processes such as feeding and stress, and in areas associated with drug reward and abuse including the dopamine-rich nucleus accumbens (NAcc), which can be considered part of the basal ganglia. Because CART has been shown to colocalize with substance P, a marker of the basal ganglia direct pathway, we now test for colocalization with other markers of the direct pathway to determine if CART colocalizes with dynorphin and dopamine D1 receptors. In the NAcc, CART peptide immunoreactivity (IR) was colocalized with prodynorphin-IR in neurons. Approximately 80.1% of CART-IR cells colocalized with prodynorphin-IR, while only 27.6% of prodynorphin-IR neurons contained CART-IR, suggesting that CART cells are a subset of dynorphin cells. In contrast, only about 25% of CART-IR cell bodies demonstrated dopamine D1 receptor-IR. Because dynorphin and D1 receptors are markers for the basal ganglia direct pathway, from the NAcc to the basal ganglia output nuclei, and because CART significantly colocalizes with these markers, some CART neurons are part of the direct pathway or some comparable pathway in the accumbens. The presence of CART in NAcc neurons and the fact that NAcc projection neurons have extensive local collaterals suggest that CART may have effects in both terminal and cell body regions of the accumbens and may therefore affect information processing in the NAcc by modulating accumbal neurons.
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Affiliation(s)
- George W Hubert
- Division of Neuroscience, Yerkes National Research Center, 954 Gatewood Road, Atlanta, GA 30329, USA.
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Xu Y, Zhang W, Klaus J, Young J, Koerner I, Sheldahl LC, Hurn PD, Martínez-Murillo F, Alkayed NJ. Role of cocaine- and amphetamine-regulated transcript in estradiol-mediated neuroprotection. Proc Natl Acad Sci U S A 2006; 103:14489-94. [PMID: 16971488 PMCID: PMC1636703 DOI: 10.1073/pnas.0602932103] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Indexed: 01/17/2023] Open
Abstract
Estrogen reduces brain injury after experimental cerebral ischemia in part through a genomic mechanism of action. Using DNA microarrays, we analyzed the genomic response of the brain to estradiol, and we identified a transcript, cocaine- and amphetamine-regulated transcript (CART), that is highly induced in the cerebral cortex by estradiol under ischemic conditions. Using in vitro and in vivo models of neural injury, we confirmed and characterized CART mRNA and protein up-regulation by estradiol in surviving neurons, and we demonstrated that i.v. administration of a rat CART peptide is protective against ischemic brain injury in vivo. We further demonstrated binding of cAMP response element (CRE)-binding protein to a CART promoter CRE site in ischemic brain and rapid activation by CART of ERK in primary cultured cortical neurons. The findings suggest that CART is an important player in estrogen-mediated neuroprotection and a potential therapeutic agent for stroke and other neurodegenerative diseases.
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Affiliation(s)
- Yun Xu
- Departments of *Anesthesiology and Critical Care Medicine, and
- Department of Neurology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China
| | - Wenri Zhang
- Departments of Anesthesiology and Perioperative Medicine, and
| | - Judith Klaus
- Departments of *Anesthesiology and Critical Care Medicine, and
| | - Jennifer Young
- Departments of Anesthesiology and Perioperative Medicine, and
| | - Ines Koerner
- Departments of Anesthesiology and Perioperative Medicine, and
| | - Laird C. Sheldahl
- Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97239; and
| | - Patricia D. Hurn
- Departments of *Anesthesiology and Critical Care Medicine, and
- Departments of Anesthesiology and Perioperative Medicine, and
- Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97239; and
| | | | - Nabil J. Alkayed
- Departments of *Anesthesiology and Critical Care Medicine, and
- Departments of Anesthesiology and Perioperative Medicine, and
- Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97239; and
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Jaworski JN, Jones DC. The role of CART in the reward/reinforcing properties of psychostimulants. Peptides 2006; 27:1993-2004. [PMID: 16766084 DOI: 10.1016/j.peptides.2006.03.034] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Accepted: 03/27/2006] [Indexed: 11/20/2022]
Abstract
Cocaine- and amphetamine-regulated transcript (CART) peptides are putative neurotransmitters which appear to play a role in the rewarding and reinforcing effects of both natural (food) and unnatural (psychostimulants) stimuli. There is extensive anatomical, pharmacological, and behavioral evidence supporting the importance of CART peptides in psychostimulant, namely cocaine and amphetamine, abuse. For instance, CART mRNA and peptides are found in brain regions considered important in the reward and reinforcement of psychostimulants including the ventral tegmental area and the nucleus accumbens, which are part of the mesolimbic dopamine system. Consequently, in a pharmacological sense, CART peptides have been closely linked to the actions of mesolimbic dopamine. In addition, under certain conditions, psychostimulants alter CART mRNA and peptide levels. However, the exact conditions and mechanisms are unclear and may involve CART modulation by corticosterone and/or cyclic AMP response element binding protein (CREB). Finally, behavioral studies on CART and psychostimulants suggest a modulatory role for CART in the actions of psychostimulants as central administration of CART attenuates the behavioral effects of cocaine. This review discusses the anatomical, pharmacological, and behavioral evidence implicating a role for CART peptide in the rewarding and reinforcing properties of psychostimulants.
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Affiliation(s)
- Jason N Jaworski
- Department of Behavioral Neuroscience, School of Medicine, Oregon Health & Sciences University, Portland, OR 97239, USA.
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Abstract
CART peptides are important neuropeptides that are involved in a variety of physiologic processes. The regulation of the CART gene is critical since peptides are regulated and secreted in response to specific stimuli. CART mRNA must also be controlled in order to respond to specific stimuli such as psychostimulant drugs and leptin. The regulation of the CART gene is central to maintaining homeostasis of peptide production. The 5' upstream region of the CART gene contains powerful regulatory elements that must be involved in transcriptional regulation via different signaling pathways. This review touches on several aspects related to CART gene regulation such as: (i) CART genomic structure, (ii) stimuli that alter CART mRNA levels, (iii) promoter characterization, (iv) role of the cAMP/PKA/CREB signal transduction pathway, and (v) role of the CART 5' and 3' ends in CART mRNA regulation. The goal of this review is to present current data so as to encourage further work in the field of CART gene regulation.
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Affiliation(s)
- Geraldina Dominguez
- Neuroscience Division, Yerkes National Primate Center of Emory University, Atlanta, GA 30329, USA.
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Vicentic A, Jones DC. The CART (Cocaine- and Amphetamine-Regulated Transcript) System in Appetite and Drug Addiction. J Pharmacol Exp Ther 2006; 320:499-506. [PMID: 16840648 DOI: 10.1124/jpet.105.091512] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
CART (cocaine- and amphetamine-regulated transcript) peptides are neuromodulators that are involved in feeding, drug reward, stress, cardiovascular function, and bone remodeling. CART peptides are abundant but discretely distributed in the brain, pituitary and adrenal glands, pancreas, and gut. High expression of CART in discrete hypothalamic nuclei associated with feeding has led to behavioral and pharmacological studies that strongly support an anorectic action of CART in feeding. Subsequent studies on humans and transgenic animals provide additional evidence that CART is important in the regulation of appetite as mutations in the CART gene are linked to eating disorders, including obesity and anorexia. The expression of CART in the mesolimbic dopamine circuit has lead to functional studies demonstrating CART's psychostimulant-like effects on locomotor activity and conditioned place preference in rats. These and other findings demonstrated that CART modulates mesolimbic dopamine systems and affects psychostimulant-induced reward and reinforcing behaviors. The link between CART and psychostimulants was substantiated by demonstrating alterations of the CART system in human cocaine addicts. CART seems to regulate the mesolimbic dopamine system, which serves as a common mechanism of action for both feeding and addiction. Indeed, recent studies that demonstrated CART projections from specific hypothalamic areas associated with feeding to specific mesolimbic areas linked to reward/motivation behaviors provide evidence that CART may be an important connection between food- and drug-related rewards. Given the enormous public health burden of both obesity and drug addiction, future studies exploring the pharmacotherapies targeting CART peptide represent an exciting and challenging research area.
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Affiliation(s)
- Aleksandra Vicentic
- Yerkes National Primate Research Center of Emory University, Atlanta, GA 30329, USA.
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