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Puglisi-Allegra S, Lazzeri G, Busceti CL, Giorgi FS, Biagioni F, Fornai F. Lithium engages autophagy for neuroprotection and neuroplasticity: translational evidence for therapy. Neurosci Biobehav Rev 2023; 148:105148. [PMID: 36996994 DOI: 10.1016/j.neubiorev.2023.105148] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/23/2023] [Accepted: 03/26/2023] [Indexed: 03/30/2023]
Abstract
Here an overview is provided on therapeutic/neuroprotective effects of Lithium (Li+) in neurodegenerative and psychiatric disorders focusing on the conspicuous action of Li+ through autophagy. The effects on the autophagy machinery remain the key molecular mechanisms to explain the protective effects of Li+ for neurodegenerative diseases, offering potential therapeutic strategies for the treatment of neuropsychiatric disorders and emphasizes a crossroad linking autophagy, neurodegenerative disorders, and mood stabilization. Sensitization by psychostimulants points to several mechanisms involved in psychopathology, most also crucial in neurodegenerative disorders. Evidence shows the involvement of autophagy and metabotropic Glutamate receptors-5 (mGluR5) in neurodegeneration due to methamphetamine neurotoxicity as well as in neuroprotection, both in vitro and in vivo models. More recently, Li+ was shown to modulate autophagy through its action on mGluR5, thus pointing to an additional way of autophagy engagement by Li+ and to a substantial role of mGluR5 in neuroprotection related to neural e neuropsychiatry diseases. We propose Li+ engagement of autophagy through the canonical mechanisms of autophagy machinery and through the intermediary of mGluR5.
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2
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Shukla M, Vincent B. Methamphetamine abuse disturbs the dopaminergic system to impair hippocampal-based learning and memory: An overview of animal and human investigations. Neurosci Biobehav Rev 2021; 131:541-559. [PMID: 34606820 DOI: 10.1016/j.neubiorev.2021.09.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 08/09/2021] [Accepted: 09/12/2021] [Indexed: 12/12/2022]
Abstract
Diverse intellectual functions including memory are some important aspects of cognition. Dopamine is a neurotransmitter of the catecholamine family, which contributes to the experience of pleasure and/or emotional states but also plays crucial roles in learning and memory. Methamphetamine is an illegal drug, the abuse of which leads to long lasting pathological manifestations in the brain. Chronic methamphetamine-induced neurotoxicity results in an alteration of various parts of the memory systems by affecting learning processes, an effect attributed to the structural similarities of this drug with dopamine. An evolving field of research established how cognitive deficits in abusers arise and how they could possibly trigger neurodegenerative disorders. Thus, the drugs-induced tenacious neurophysiological changes of the dopamine system trigger cognitive deficits, thereby affirming the influence of this addictive drug on learning, memory and executive function in human abusers. Here we present an overview of the effects of methamphetamine abuse on cognitive functions, dopaminergic transmission and hippocampal integrity as they have been validated in animals and in humans during the past 20 years.
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Affiliation(s)
- Mayuri Shukla
- Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, 73170, Thailand
| | - Bruno Vincent
- Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom, 73170, Thailand; Centre National de la Recherche Scientifique, 2 Rue Michel Ange, 75016, Paris, France.
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3
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Lazzeri G, Busceti CL, Biagioni F, Fabrizi C, Morucci G, Giorgi FS, Ferrucci M, Lenzi P, Puglisi-Allegra S, Fornai F. Norepinephrine Protects against Methamphetamine Toxicity through β2-Adrenergic Receptors Promoting LC3 Compartmentalization. Int J Mol Sci 2021; 22:7232. [PMID: 34281286 PMCID: PMC8269332 DOI: 10.3390/ijms22137232] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/01/2021] [Accepted: 07/03/2021] [Indexed: 01/18/2023] Open
Abstract
Norepinephrine (NE) neurons and extracellular NE exert some protective effects against a variety of insults, including methamphetamine (Meth)-induced cell damage. The intimate mechanism of protection remains difficult to be analyzed in vivo. In fact, this may occur directly on target neurons or as the indirect consequence of NE-induced alterations in the activity of trans-synaptic loops. Therefore, to elude neuronal networks, which may contribute to these effects in vivo, the present study investigates whether NE still protects when directly applied to Meth-treated PC12 cells. Meth was selected based on its detrimental effects along various specific brain areas. The study shows that NE directly protects in vitro against Meth-induced cell damage. The present study indicates that such an effect fully depends on the activation of plasma membrane β2-adrenergic receptors (ARs). Evidence indicates that β2-ARs activation restores autophagy, which is impaired by Meth administration. This occurs via restoration of the autophagy flux and, as assessed by ultrastructural morphometry, by preventing the dissipation of microtubule-associated protein 1 light chain 3 (LC3) from autophagy vacuoles to the cytosol, which is produced instead during Meth toxicity. These findings may have an impact in a variety of degenerative conditions characterized by NE deficiency along with autophagy impairment.
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Affiliation(s)
- Gloria Lazzeri
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, via Roma 55, 56126 Pisa, Italy; (G.L.); (G.M.); (F.S.G.); (M.F.); (P.L.)
| | - Carla L. Busceti
- I.R.C.C.S. Neuromed, via Atinense 18, 86077 Pozzilli, Italy; (C.L.B.); (F.B.); (S.P.-A.)
| | - Francesca Biagioni
- I.R.C.C.S. Neuromed, via Atinense 18, 86077 Pozzilli, Italy; (C.L.B.); (F.B.); (S.P.-A.)
| | - Cinzia Fabrizi
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, via A. Borelli 50, 00161 Rome, Italy;
| | - Gabriele Morucci
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, via Roma 55, 56126 Pisa, Italy; (G.L.); (G.M.); (F.S.G.); (M.F.); (P.L.)
| | - Filippo S. Giorgi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, via Roma 55, 56126 Pisa, Italy; (G.L.); (G.M.); (F.S.G.); (M.F.); (P.L.)
| | - Michela Ferrucci
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, via Roma 55, 56126 Pisa, Italy; (G.L.); (G.M.); (F.S.G.); (M.F.); (P.L.)
| | - Paola Lenzi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, via Roma 55, 56126 Pisa, Italy; (G.L.); (G.M.); (F.S.G.); (M.F.); (P.L.)
| | | | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, via Roma 55, 56126 Pisa, Italy; (G.L.); (G.M.); (F.S.G.); (M.F.); (P.L.)
- I.R.C.C.S. Neuromed, via Atinense 18, 86077 Pozzilli, Italy; (C.L.B.); (F.B.); (S.P.-A.)
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4
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Limanaqi F, Busceti CL, Celli R, Biagioni F, Fornai F. Autophagy as a gateway for the effects of methamphetamine: From neurotransmitter release and synaptic plasticity to psychiatric and neurodegenerative disorders. Prog Neurobiol 2021; 204:102112. [PMID: 34171442 DOI: 10.1016/j.pneurobio.2021.102112] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/27/2021] [Accepted: 06/18/2021] [Indexed: 02/07/2023]
Abstract
As a major eukaryotic cell clearing machinery, autophagy grants cell proteostasis, which is key for neurotransmitter release, synaptic plasticity, and neuronal survival. In line with this, besides neuropathological events, autophagy dysfunctions are bound to synaptic alterations that occur in mental disorders, and early on, in neurodegenerative diseases. This is also the case of methamphetamine (METH) abuse, which leads to psychiatric disturbances and neurotoxicity. While consistently altering the autophagy machinery, METH produces behavioral and neurotoxic effects through molecular and biochemical events that can be recapitulated by autophagy blockade. These consist of altered physiological dopamine (DA) release, abnormal stimulation of DA and glutamate receptors, as well as oxidative, excitotoxic, and neuroinflammatory events. Recent molecular insights suggest that METH early impairs the autophagy machinery, though its functional significance remains to be investigated. Here we discuss evidence suggesting that alterations of DA transmission and autophagy are intermingled within a chain of events underlying behavioral alterations and neurodegenerative phenomena produced by METH. Understanding how METH alters the autophagy machinery is expected to provide novel insights into the neurobiology of METH addiction sharing some features with psychiatric disorders and parkinsonism.
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Affiliation(s)
- Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma, 55, 56126, Pisa, PI, Italy
| | | | - Roberta Celli
- IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy
| | | | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma, 55, 56126, Pisa, PI, Italy; IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy.
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5
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Autophagy status as a gateway for stress-induced catecholamine interplay in neurodegeneration. Neurosci Biobehav Rev 2021; 123:238-256. [PMID: 33497785 DOI: 10.1016/j.neubiorev.2021.01.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 01/08/2021] [Accepted: 01/09/2021] [Indexed: 12/13/2022]
Abstract
The catecholamine-containing brainstem nuclei locus coeruleus (LC) and ventral tegmental area (VTA) are critically involved in stress responses. Alterations of catecholamine systems during chronic stress may contribute to neurodegeneration, including cognitive decline. Stress-related catecholamine alterations, while contributing to anxiety and depression, might accelerate neuronal degeneration by increasing the formation of toxic dopamine and norepinephrine by-products. These, in turn, may impair proteostasis within a variety of cortical and subcortical areas. In particular, the molecular events governing neurotransmission, neuroplasticity, and proteostasis within LC and VTA affect a variety of brain areas. Therefore, we focus on alterations of autophagy machinery in these nuclei as a relevant trigger in this chain of events. In fact, these catecholamine-containing areas are mostly prone to autophagy-dependent neurodegeneration. Thus, we propose a dynamic hypothesis according to which stress-induced autophagy alterations within the LC-VTA network foster a cascade towards early neurodegeneration within these nuclei.
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6
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Giorgi FS, Galgani A, Puglisi-Allegra S, Limanaqi F, Busceti CL, Fornai F. Locus Coeruleus and neurovascular unit: From its role in physiology to its potential role in Alzheimer's disease pathogenesis. J Neurosci Res 2020; 98:2406-2434. [PMID: 32875628 DOI: 10.1002/jnr.24718] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/26/2020] [Accepted: 08/08/2020] [Indexed: 12/15/2022]
Abstract
Locus coeruleus (LC) is the main noradrenergic (NA) nucleus of the central nervous system. LC degenerates early during Alzheimer's disease (AD) and NA loss might concur to AD pathogenesis. Aside from neurons, LC terminals provide dense innervation of brain intraparenchymal arterioles/capillaries, and NA modulates astrocyte functions. The term neurovascular unit (NVU) defines the strict anatomical/functional interaction occurring between neurons, glial cells, and brain vessels. NVU plays a fundamental role in coupling the energy demand of activated brain regions with regional cerebral blood flow, it includes the blood-brain barrier (BBB), plays an active role in neuroinflammation, and participates also to the glymphatic system. NVU alteration is involved in AD pathophysiology through several mechanisms, mainly related to a relative oligoemia in activated brain regions and impairment of structural and functional BBB integrity, which contributes also to the intracerebral accumulation of insoluble amyloid. We review the existing data on the morphological features of LC-NA innervation of the NVU, as well as its contribution to neurovascular coupling and BBB proper functioning. After introducing the main experimental data linking LC with AD, which have repeatedly shown a key role of neuroinflammation and increased amyloid plaque formation, we discuss the potential mechanisms by which the loss of NVU modulation by LC might contribute to AD pathogenesis. Surprisingly, thus far not so many studies have tested directly these mechanisms in models of AD in which LC has been lesioned experimentally. Clarifying the interaction of LC with NVU in AD pathogenesis may disclose potential therapeutic targets for AD.
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Affiliation(s)
- Filippo Sean Giorgi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,Neurology Unit, Pisa University Hospital, Pisa, Italy
| | | | | | - Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,I.R.C.C.S. I.N.M. Neuromed, Pozzilli, Italy
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7
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Hassani OK, Rymar VV, Nguyen KQ, Huo L, Cloutier JF, Miller FD, Sadikot AF. The noradrenergic system is necessary for survival of vulnerable midbrain dopaminergic neurons: implications for development and Parkinson's disease. Neurobiol Aging 2019; 85:22-37. [PMID: 31734438 DOI: 10.1016/j.neurobiolaging.2019.09.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 09/17/2019] [Accepted: 09/19/2019] [Indexed: 12/22/2022]
Abstract
The cause of midbrain dopaminergic (mDA) neuron loss in sporadic Parkinson's disease (PD) is multifactorial, involving cell autonomous factors, cell-cell interactions, and the effects of environmental toxins. Early loss of neurons in the locus coeruleus (LC), the main source of ascending noradrenergic (NA) projections, is an important feature of PD and other neurodegenerative disorders. We hypothesized that NA afferents provide trophic support for vulnerable mDA neurons. We demonstrate that depriving mDA neurons of NA input increases postnatal apoptosis and decreases cell survival in young adult rodents, with relative sparing of calbindin-positive subpopulations known to be resistant to degeneration in PD. As a mechanism, we propose that the neurotrophin brain-derived neurotrophic factor (BDNF) modulates anterograde survival effects of LC inputs to mDA neurons. We demonstrate that the LC is rich in BDNF mRNA in postnatal and young adult brains. Early postnatal NA denervation reduces both BDNF protein and activation of TrkB receptors in the ventral midbrain. Furthermore, overexpression of BDNF in NA afferents in transgenic mice increases mDA neuronal survival. Finally, increasing NA activity in primary cultures of mDA neurons improves survival, an effect that is additive or synergistic in the presence of different concentrations of BDNF. Taken together, our results point to a novel mechanism whereby LC afferents couple BDNF effects and NA activity to provide anterograde trophic support for vulnerable mDA neurons. Early loss of NA activity and anterograde neurotrophin support may contribute to degeneration of vulnerable neurons in PD and other neurodegenerative disorders.
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Affiliation(s)
- Oum Kaltoum Hassani
- Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Vladimir V Rymar
- Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Khanh Q Nguyen
- Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Lia Huo
- Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Jean-François Cloutier
- Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Freda D Miller
- Departments of Medical Genetics, Microbiology & Physiology, The Hospital for Sick Children Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - Abbas F Sadikot
- Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.
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8
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Ferrucci M, Limanaqi F, Ryskalin L, Biagioni F, Busceti CL, Fornai F. The Effects of Amphetamine and Methamphetamine on the Release of Norepinephrine, Dopamine and Acetylcholine From the Brainstem Reticular Formation. Front Neuroanat 2019; 13:48. [PMID: 31133823 PMCID: PMC6524618 DOI: 10.3389/fnana.2019.00048] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/26/2019] [Indexed: 12/22/2022] Open
Abstract
Amphetamine (AMPH) and methamphetamine (METH) are widely abused psychostimulants, which produce a variety of psychomotor, autonomic and neurotoxic effects. The behavioral and neurotoxic effects of both compounds (from now on defined as AMPHs) stem from a fair molecular and anatomical specificity for catecholamine-containing neurons, which are placed in the brainstem reticular formation (RF). In fact, the structural cross-affinity joined with the presence of shared molecular targets between AMPHs and catecholamine provides the basis for a quite selective recruitment of brainstem catecholamine neurons following AMPHs administration. A great amount of investigations, commentary manuscripts and books reported a pivotal role of mesencephalic dopamine (DA)-containing neurons in producing behavioral and neurotoxic effects of AMPHs. Instead, the present review article focuses on catecholamine reticular neurons of the low brainstem. In fact, these nuclei add on DA mesencephalic cells to mediate the effects of AMPHs. Among these, we also include two pontine cholinergic nuclei. Finally, we discuss the conundrum of a mixed neuronal population, which extends from the pons to the periaqueductal gray (PAG). In this way, a number of reticular nuclei beyond classic DA mesencephalic cells are considered to extend the scenario underlying the neurobiology of AMPHs abuse. The mechanistic approach followed here to describe the action of AMPHs within the RF is rooted on the fine anatomy of this region of the brainstem. This is exemplified by a few medullary catecholamine neurons, which play a pivotal role compared with the bulk of peripheral sympathetic neurons in sustaining most of the cardiovascular effects induced by AMPHs.
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Affiliation(s)
- Michela Ferrucci
- Human Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Fiona Limanaqi
- Human Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Larisa Ryskalin
- Human Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | | | - Francesco Fornai
- Human Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
- IRCCS Neuromed, Pozzilli, Italy
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9
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mTOR Modulates Methamphetamine-Induced Toxicity through Cell Clearing Systems. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:6124745. [PMID: 30647813 PMCID: PMC6311854 DOI: 10.1155/2018/6124745] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/31/2018] [Indexed: 11/17/2022]
Abstract
Methamphetamine (METH) is abused worldwide, and it represents a threat for public health. METH exposure induces a variety of detrimental effects. In fact, METH produces a number of oxidative species, which lead to lipid peroxidation, protein misfolding, and nuclear damage. Cell clearing pathways such as ubiquitin-proteasome (UP) and autophagy (ATG) are involved in METH-induced oxidative damage. Although these pathways were traditionally considered to operate as separate metabolic systems, recent studies demonstrate their interconnection at the functional and biochemical level. Very recently, the convergence between UP and ATG was evidenced within a single organelle named autophagoproteasome (APP), which is suppressed by mTOR activation. In the present research study, the occurrence of APP during METH toxicity was analyzed. In fact, coimmunoprecipitation indicates a binding between LC3 and P20S particles, which also recruit p62 and alpha-synuclein. The amount of METH-induced toxicity correlates with APP levels. Specific markers for ATG and UP, such as LC3 and P20S in the cytosol, and within METH-induced vacuoles, were measured at different doses and time intervals following METH administration either alone or combined with mTOR modulators. Western blotting, coimmunoprecipitation, light microscopy, confocal microscopy, plain transmission electron microscopy, and immunogold staining were used to document the effects of mTOR modulation on METH toxicity and the merging of UP with ATG markers within APPs. METH-induced cell death is prevented by mTOR inhibition, while it is worsened by mTOR activation, which correlates with the amount of autophagoproteasomes. The present data, which apply to METH toxicity, are also relevant to provide a novel insight into cell clearing pathways to counteract several kinds of oxidative damage.
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10
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Abstract
SIGNIFICANCE Oxidative stress increases in the brain with aging and neurodegenerative diseases. Previous work emphasized irreversible oxidative damage in relation to cognitive impairment. This research has evolved to consider a continuum of alterations, from redox signaling to oxidative damage, which provides a basis for understanding the onset and progression of cognitive impairment. This review provides an update on research linking redox signaling to altered function of neural circuits involved in information processing and memory. Recent Advances: Starting in middle age, redox signaling triggers changes in nervous system physiology described as senescent physiology. Hippocampal senescent physiology involves decreased cell excitability, altered synaptic plasticity, and decreased synaptic transmission. Recent studies indicate N-methyl-d-aspartate and ryanodine receptors and Ca2+ signaling molecules as molecular substrates of redox-mediated senescent physiology. CRITICAL ISSUES We review redox homeostasis mechanisms and consider the chemical character of reactive oxygen and nitrogen species and their role in regulating different transmitter systems. In this regard, senescent physiology may represent the co-opting of pathways normally responsible for feedback regulation of synaptic transmission. Furthermore, differences across transmitter systems may underlie differential vulnerability of brain regions and neuronal circuits to aging and disease. FUTURE DIRECTIONS It will be important to identify the intrinsic mechanisms for the shift in oxidative/reductive processes. Intrinsic mechanism will depend on the transmitter system, oxidative stressors, and expression/activity of antioxidant enzymes. In addition, it will be important to identify how intrinsic processes interact with other aging factors, including changes in inflammatory or hormonal signals. Antioxid. Redox Signal. 28, 1724-1745.
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Affiliation(s)
- Ashok Kumar
- 1 Department of Neuroscience, McKnight Brain Institute, University of Florida , Gainesville, Florida
| | - Brittney Yegla
- 1 Department of Neuroscience, McKnight Brain Institute, University of Florida , Gainesville, Florida
| | - Thomas C Foster
- 1 Department of Neuroscience, McKnight Brain Institute, University of Florida , Gainesville, Florida.,2 Genetics and Genomics Program, Genetics Institute, University of Florida , Gainesville, Florida
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11
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Zhu MY. Noradrenergic Modulation on Dopaminergic Neurons. Neurotox Res 2018; 34:848-859. [DOI: 10.1007/s12640-018-9889-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 03/05/2018] [Accepted: 03/08/2018] [Indexed: 12/24/2022]
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12
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Striatal norepinephrine efflux in l-DOPA-induced dyskinesia. Neurochem Int 2018; 114:85-98. [DOI: 10.1016/j.neuint.2018.01.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 01/12/2018] [Accepted: 01/17/2018] [Indexed: 11/23/2022]
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13
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Giorgi FS, Ryskalin L, Ruffoli R, Biagioni F, Limanaqi F, Ferrucci M, Busceti CL, Bonuccelli U, Fornai F. The Neuroanatomy of the Reticular Nucleus Locus Coeruleus in Alzheimer's Disease. Front Neuroanat 2017; 11:80. [PMID: 28974926 PMCID: PMC5610679 DOI: 10.3389/fnana.2017.00080] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 09/05/2017] [Indexed: 11/13/2022] Open
Abstract
Alzheimer’s Disease (AD) features the accumulation of β-amyloid and Tau aggregates, which deposit as extracellular plaques and intracellular neurofibrillary tangles (NFTs), respectively. Neuronal Tau aggregates may appear early in life, in the absence of clinical symptoms. This occurs in the brainstem reticular formation and mostly within Locus Coeruleus (LC), which is consistently affected during AD. LC is the main source of forebrain norepinephrine (NE) and it modulates a variety of functions including sleep-waking cycle, alertness, synaptic plasticity, and memory. The iso-dendritic nature of LC neurons allows their axons to spread NE throughout the whole forebrain. Likewise, a prion-like hypothesis suggests that Tau aggregates may travel along LC axons to reach out cortical neurons. Despite this timing is compatible with cross-sectional studies, there is no actual evidence for a causal relationship between these events. In the present mini-review, we dedicate special emphasis to those various mechanisms that may link degeneration of LC neurons to the onset of AD pathology. This includes the hypothesis that a damage to LC neurons contributes to the onset of dementia due to a loss of neuroprotective effects or, even the chance that, LC degenerates independently from cortical pathology. At the same time, since LC neurons are lost in a variety of neuropsychiatric disorders we considered which molecular mechanism may render these brainstem neurons so vulnerable.
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Affiliation(s)
- Filippo S Giorgi
- Section of Neurology, Pisa University Hospital, Department of Clinical and Experimental Medicine, University of PisaPisa, Italy
| | - Larisa Ryskalin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of PisaPisa, Italy
| | - Riccardo Ruffoli
- Department of Translational Research and New Technologies in Medicine and Surgery, University of PisaPisa, Italy
| | | | - Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of PisaPisa, Italy
| | - Michela Ferrucci
- Department of Translational Research and New Technologies in Medicine and Surgery, University of PisaPisa, Italy
| | | | - Ubaldo Bonuccelli
- Section of Neurology, Pisa University Hospital, Department of Clinical and Experimental Medicine, University of PisaPisa, Italy
| | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of PisaPisa, Italy.,I.R.C.C.S. I.N.M. NeuromedPozzilli, Italy
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14
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Chalermpalanupap T, Weinshenker D, Rorabaugh JM. Down but Not Out: The Consequences of Pretangle Tau in the Locus Coeruleus. Neural Plast 2017; 2017:7829507. [PMID: 29038736 PMCID: PMC5605916 DOI: 10.1155/2017/7829507] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/20/2017] [Accepted: 07/20/2017] [Indexed: 12/12/2022] Open
Abstract
Degeneration of locus coeruleus (LC) is an underappreciated hallmark of Alzheimer's disease (AD). The LC is the main source of norepinephrine (NE) in the forebrain, and its degeneration is highly correlated with cognitive impairment and amyloid-beta (Aβ) and tangle pathology. Hyperphosphorylated tau in the LC is among the first detectable AD-like neuropathology in the brain, and while the LC/NE system impacts multiple aspects of AD (e.g., cognition, neuropathology, and neuroinflammation), the functional consequences of hyperphosphorylated tau accrual on LC neurons are not known. Recent evidence suggests that LC neurons accumulate aberrant tau species for decades before frank LC cell body degeneration occurs in AD, suggesting that a therapeutic window exists. In this review, we combine the literature on how pathogenic tau affects forebrain neurons with the known properties and degeneration patterns of LC neurons to synthesize hypotheses on hyperphosphorylated tau-induced dysfunction of LC neurons and the prion-like spread of pretangle tau from the LC to the forebrain. We also propose novel experiments using both in vitro and in vivo models to address the many questions surrounding the impact of hyperphosphorylated tau on LC neurons in AD and its role in disease progression.
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Affiliation(s)
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jacki M. Rorabaugh
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
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15
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Cubells JF, Schroeder JP, Barrie ES, Manvich DF, Sadee W, Berg T, Mercer K, Stowe TA, Liles LC, Squires KE, Mezher A, Curtin P, Perdomo DL, Szot P, Weinshenker D. Human Bacterial Artificial Chromosome (BAC) Transgenesis Fully Rescues Noradrenergic Function in Dopamine β-Hydroxylase Knockout Mice. PLoS One 2016; 11:e0154864. [PMID: 27148966 PMCID: PMC4857931 DOI: 10.1371/journal.pone.0154864] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/20/2016] [Indexed: 12/22/2022] Open
Abstract
Dopamine β-hydroxylase (DBH) converts dopamine (DA) to norepinephrine (NE) in noradrenergic/adrenergic cells. DBH deficiency prevents NE production and causes sympathetic failure, hypotension and ptosis in humans and mice; DBH knockout (Dbh -/-) mice reveal other NE deficiency phenotypes including embryonic lethality, delayed growth, and behavioral defects. Furthermore, a single nucleotide polymorphism (SNP) in the human DBH gene promoter (-970C>T; rs1611115) is associated with variation in serum DBH activity and with several neurological- and neuropsychiatric-related disorders, although its impact on DBH expression is controversial. Phenotypes associated with DBH deficiency are typically treated with L-3,4-dihydroxyphenylserine (DOPS), which can be converted to NE by aromatic acid decarboxylase (AADC) in the absence of DBH. In this study, we generated transgenic mice carrying a human bacterial artificial chromosome (BAC) encompassing the DBH coding locus as well as ~45 kb of upstream and ~107 kb of downstream sequence to address two issues. First, we characterized the neuroanatomical, neurochemical, physiological, and behavioral transgenic rescue of DBH deficiency by crossing the BAC onto a Dbh -/- background. Second, we compared human DBH mRNA abundance between transgenic lines carrying either a "C" or a "T" at position -970. The BAC transgene drove human DBH mRNA expression in a pattern indistinguishable from the endogenous gene, restored normal catecholamine levels to the peripheral organs and brain of Dbh -/- mice, and fully rescued embryonic lethality, delayed growth, ptosis, reduced exploratory activity, and seizure susceptibility. In some cases, transgenic rescue was superior to DOPS. However, allelic variation at the rs1611115 SNP had no impact on mRNA levels in any tissue. These results indicate that the human BAC contains all of the genetic information required for tissue-specific, functional expression of DBH and can rescue all measured Dbh deficiency phenotypes, but did not reveal an impact of the rs11115 variant on DBH expression in mice.
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Affiliation(s)
- Joseph F. Cubells
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Emory Autism Center, Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Jason P. Schroeder
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Elizabeth S. Barrie
- Center for Pharmacogenomics, College of Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Daniel F. Manvich
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Wolfgang Sadee
- Center for Pharmacogenomics, College of Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Tiina Berg
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Kristina Mercer
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, Georgia, United States of America
| | - Taylor A. Stowe
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - L. Cameron Liles
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Katherine E. Squires
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Andrew Mezher
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Patrick Curtin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Dannie L. Perdomo
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, Georgia, United States of America
| | - Patricia Szot
- MIRECC, VA Puget Sound Health Care System, Seattle, Washington, United States of America
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, United States of America
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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Kuhn DM, Angoa-Pérez M, Thomas DM. Nucleus accumbens invulnerability to methamphetamine neurotoxicity. ILAR J 2016; 52:352-65. [PMID: 23382149 DOI: 10.1093/ilar.52.3.352] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Methamphetamine (Meth) is a neurotoxic drug of abuse that damages neurons and nerve endings throughout the central nervous system. Emerging studies of human Meth addicts using both postmortem analyses of brain tissue and noninvasive imaging studies of intact brains have confirmed that Meth causes persistent structural abnormalities. Animal and human studies have also defined a number of significant functional problems and comorbid psychiatric disorders associated with long-term Meth abuse. This review summarizes the salient features of Meth-induced neurotoxicity with a focus on the dopamine (DA) neuronal system. DA nerve endings in the caudate-putamen (CPu) are damaged by Meth in a highly delimited manner. Even within the CPu, damage is remarkably heterogeneous, with ventral and lateral aspects showing the greatest deficits. The nucleus accumbens (NAc) is largely spared the damage that accompanies binge Meth intoxication, but relatively subtle changes in the disposition of DA in its nerve endings can lead to dramatic increases in Meth-induced toxicity in the CPu and overcome the normal resistance of the NAc to damage. In contrast to the CPu, where DA neuronal deficiencies are persistent, alterations in the NAc show a partial recovery. Animal models have been indispensable in studies of the causes and consequences of Meth neurotoxicity and in the development of new therapies. This research has shown that increases in cytoplasmic DA dramatically broaden the neurotoxic profile of Meth to include brain structures not normally targeted for damage. The resistance of the NAc to Meth-induced neurotoxicity and its ability to recover reveal a fundamentally different neuroplasticity by comparison to the CPu. Recruitment of the NAc as a target of Meth neurotoxicity by alterations in DA homeostasis is significant in light of the numerous important roles played by this brain structure.
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Mejias-Aponte CA. Specificity and impact of adrenergic projections to the midbrain dopamine system. Brain Res 2016; 1641:258-73. [PMID: 26820641 DOI: 10.1016/j.brainres.2016.01.036] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Revised: 01/11/2016] [Accepted: 01/20/2016] [Indexed: 12/18/2022]
Abstract
Dopamine (DA) is a neuromodulator that regulates different brain circuits involved in cognitive functions, motor coordination, and emotions. Dysregulation of DA is associated with many neurological and psychiatric disorders such as Parkinson's disease and substance abuse. Several lines of research have shown that the midbrain DA system is regulated by the central adrenergic system. This review focuses on adrenergic interactions with midbrain DA neurons. It discusses the current neuroanatomy including source of adrenergic innervation, type of synapses, and adrenoceptors expression. It also discusses adrenergic regulation of DA cell activity and neurotransmitter release. Finally, it reviews several neurological and psychiatric disorders where changes in adrenergic system are associated with dysregulation of the midbrain DA system. This article is part of a Special Issue entitled SI: Noradrenergic System.
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Affiliation(s)
- Carlos A Mejias-Aponte
- National Institute on Drug Abuse Histology Core, Neuronal Networks Section, Integrative Neuroscience Research Branch, National Institute on Drug Abuse, Biomedical Research Center, 251 Bayview Blvd, Suite 200, Baltimore, MD 21224, USA.
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18
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Gaval-Cruz M, Goertz RB, Puttick DJ, Bowles DE, Meyer RC, Hall RA, Ko D, Paladini CA, Weinshenker D. Chronic loss of noradrenergic tone produces β-arrestin2-mediated cocaine hypersensitivity and alters cellular D2 responses in the nucleus accumbens. Addict Biol 2016; 21:35-48. [PMID: 25123018 DOI: 10.1111/adb.12174] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cocaine blocks plasma membrane monoamine transporters and increases extracellular levels of dopamine (DA), norepinephrine (NE) and serotonin (5-HT). The addictive properties of cocaine are mediated primarily by DA, while NE and 5-HT play modulatory roles. Chronic inhibition of dopamine β-hydroxylase (DBH), which converts DA to NE, increases the aversive effects of cocaine and reduces cocaine use in humans, and produces behavioral hypersensitivity to cocaine and D2 agonism in rodents, but the underlying mechanism is unknown. We found a decrease in β-arrestin2 (βArr2) in the nucleus accumbens (NAc) following chronic genetic or pharmacological DBH inhibition, and overexpression of βArr2 in the NAc normalized cocaine-induced locomotion in DBH knockout (Dbh -/-) mice. The D2/3 agonist quinpirole decreased excitability in NAc medium spiny neurons (MSNs) from control, but not Dbh -/- animals, where instead there was a trend for an excitatory effect. The Gαi inhibitor NF023 abolished the quinpirole-induced decrease in excitability in control MSNs, but had no effect in Dbh -/- MSNs, whereas the Gαs inhibitor NF449 restored the ability of quinpirole to decrease excitability in Dbh -/- MSNs, but had no effect in control MSNs. These results suggest that chronic loss of noradrenergic tone alters behavioral responses to cocaine via decreases in βArr2 and cellular responses to D2/D3 activation, potentially via changes in D2-like receptor G-protein coupling in NAc MSNs.
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Affiliation(s)
- Meriem Gaval-Cruz
- Department of Human Genetics; Emory University School of Medicine; Atlanta GA USA
| | - Richard B. Goertz
- Department of Biology; Neurosciences Institute; University of Texas at San Antonio; San Antonio TX USA
| | - Daniel J. Puttick
- Department of Human Genetics; Emory University School of Medicine; Atlanta GA USA
| | - Dawn E. Bowles
- Department of Surgery; Duke University School of Medicine; Durham NC USA
| | - Rebecca C. Meyer
- Department of Pharmacology; Emory University School of Medicine; Atlanta GA USA
| | - Randy A. Hall
- Department of Pharmacology; Emory University School of Medicine; Atlanta GA USA
| | - Daijin Ko
- Department of Management Science and Statistics; University of Texas at San Antonio; San Antonio TX USA
| | - Carlos A. Paladini
- Department of Biology; Neurosciences Institute; University of Texas at San Antonio; San Antonio TX USA
| | - David Weinshenker
- Department of Human Genetics; Emory University School of Medicine; Atlanta GA USA
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19
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Devoto P, Flore G, Saba P, Bini V, Gessa GL. The dopamine beta-hydroxylase inhibitor nepicastat increases dopamine release and potentiates psychostimulant-induced dopamine release in the prefrontal cortex. Addict Biol 2014; 19:612-22. [PMID: 23289939 DOI: 10.1111/adb.12026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The dopamine-beta-hydroxylase inhibitor nepicastat has been shown to reproduce disulfiram ability to suppress the reinstatement of cocaine seeking after extinction in rats. To clarify its mechanism of action, we examined the effect of nepicastat, given alone or in association with cocaine or amphetamine, on catecholamine release in the medial prefrontal cortex and the nucleus accumbens, two key regions involved in the reinforcing and motivational effects of cocaine and in the reinstatement of cocaine seeking. Nepicastat effect on catecholamines was evaluated by microdialysis in freely moving rats. Nepicastat reduced noradrenaline release both in the medial prefrontal cortex and in the nucleus accumbens, and increased dopamine release in the medial prefrontal cortex but not in the nucleus accumbens. Moreover, nepicastat markedly potentiated cocaine- and amphetamine-induced extracellular dopamine accumulation in the medial prefrontal cortex but not in the nucleus accumbens. Extracellular dopamine accumulation produced by nepicastat alone or by its combination with cocaine or amphetamine was suppressed by the α2 -adrenoceptor agonist clonidine. It is suggested that nepicastat, by suppressing noradrenaline synthesis and release, eliminated the α2 -adrenoceptor mediated inhibitory mechanism that constrains dopamine release and cocaine- and amphetamine-induced dopamine release from noradrenaline or dopamine terminals in the medial prefrontal cortex.
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Affiliation(s)
- Paola Devoto
- Department of Biomedical Sciences; Neuroscience and Clinical Pharmacology Division; University of Cagliari; Italy
- Center of Excellence ‘Neurobiology of Addiction’; University of Cagliari; Italy
- ‘Guy Everett Laboratory’; University of Cagliari; Italy
| | - Giovanna Flore
- Department of Medical Sciences ‘M. Aresu’; University of Cagliari; Italy
| | - Pierluigi Saba
- Department of Biomedical Sciences; Neuroscience and Clinical Pharmacology Division; University of Cagliari; Italy
| | - Valentina Bini
- Department of Biomedical Sciences; Neuroscience and Clinical Pharmacology Division; University of Cagliari; Italy
| | - Gian Luigi Gessa
- Department of Biomedical Sciences; Neuroscience and Clinical Pharmacology Division; University of Cagliari; Italy
- Center of Excellence ‘Neurobiology of Addiction’; University of Cagliari; Italy
- ‘Guy Everett Laboratory’; University of Cagliari; Italy
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20
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Cooper DA, Kimmel HL, Manvich DF, Schmidt KT, Weinshenker D, Howell LL. Effects of pharmacologic dopamine β-hydroxylase inhibition on cocaine-induced reinstatement and dopamine neurochemistry in squirrel monkeys. J Pharmacol Exp Ther 2014; 350:144-52. [PMID: 24817036 DOI: 10.1124/jpet.113.212357] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Disulfiram has shown promise as a pharmacotherapy for cocaine dependence in clinical settings, although it has many targets, and the behavioral and molecular mechanisms underlying its efficacy are unclear. One of many biochemical actions of disulfiram is inhibition of dopamine β-hydroxylase (DBH), the enzyme that converts dopamine (DA) to norepinephrine (NE) in noradrenergic neurons. Thus, disulfiram simultaneously reduces NE and elevates DA tissue levels in the brain. In rats, both disulfiram and the selective DBH inhibitor nepicastat block cocaine-primed reinstatement, a paradigm which is thought to model some aspects of drug relapse. This is consistent with some clinical results and supports the use of DBH inhibitors for the treatment of cocaine dependence. The present study was conducted to confirm and extend these results in nonhuman primates. Squirrel monkeys trained to self-administer cocaine were pretreated with disulfiram or nepicastat prior to cocaine-induced reinstatement sessions. Neither DBH inhibitor altered cocaine-induced reinstatement. Unexpectedly, nepicastat administered alone induced a modest reinstatement effect in squirrel monkeys, but not in rats. To investigate the neurochemical mechanisms underlying the behavioral results, the effects of DBH inhibition on extracellular DA were analyzed in the nucleus accumbens (NAc) using in vivo microdialysis in squirrel monkeys. Both DBH inhibitors attenuated cocaine-induced DA overflow in the NAc. Hence, the attenuation of cocaine-induced changes in accumbal DA neurochemistry was not associated with altered cocaine-seeking behavior. Overall, the reported behavioral effects of DBH inhibition in rodent models of relapse did not extend to nonhuman primates under the conditions used in the current studies.
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Affiliation(s)
- Debra A Cooper
- Yerkes National Primate Research Center, Division of Neuropharmacology and Neurologic Diseases (D.A.C., H.L.K., L.L.H.), Department of Pharmacology (H.L.K., L.L.H.), Department of Human Genetics (D.A.C., D.F.M., K.T.S., D.W.), and Department of Psychiatry and Behavioral Sciences (L.L.H.), Emory University, Atlanta, Georgia
| | - Heather L Kimmel
- Yerkes National Primate Research Center, Division of Neuropharmacology and Neurologic Diseases (D.A.C., H.L.K., L.L.H.), Department of Pharmacology (H.L.K., L.L.H.), Department of Human Genetics (D.A.C., D.F.M., K.T.S., D.W.), and Department of Psychiatry and Behavioral Sciences (L.L.H.), Emory University, Atlanta, Georgia
| | - Daniel F Manvich
- Yerkes National Primate Research Center, Division of Neuropharmacology and Neurologic Diseases (D.A.C., H.L.K., L.L.H.), Department of Pharmacology (H.L.K., L.L.H.), Department of Human Genetics (D.A.C., D.F.M., K.T.S., D.W.), and Department of Psychiatry and Behavioral Sciences (L.L.H.), Emory University, Atlanta, Georgia
| | - Karl T Schmidt
- Yerkes National Primate Research Center, Division of Neuropharmacology and Neurologic Diseases (D.A.C., H.L.K., L.L.H.), Department of Pharmacology (H.L.K., L.L.H.), Department of Human Genetics (D.A.C., D.F.M., K.T.S., D.W.), and Department of Psychiatry and Behavioral Sciences (L.L.H.), Emory University, Atlanta, Georgia
| | - David Weinshenker
- Yerkes National Primate Research Center, Division of Neuropharmacology and Neurologic Diseases (D.A.C., H.L.K., L.L.H.), Department of Pharmacology (H.L.K., L.L.H.), Department of Human Genetics (D.A.C., D.F.M., K.T.S., D.W.), and Department of Psychiatry and Behavioral Sciences (L.L.H.), Emory University, Atlanta, Georgia
| | - Leonard L Howell
- Yerkes National Primate Research Center, Division of Neuropharmacology and Neurologic Diseases (D.A.C., H.L.K., L.L.H.), Department of Pharmacology (H.L.K., L.L.H.), Department of Human Genetics (D.A.C., D.F.M., K.T.S., D.W.), and Department of Psychiatry and Behavioral Sciences (L.L.H.), Emory University, Atlanta, Georgia
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21
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Ferrucci M, Giorgi FS, Bartalucci A, Busceti CL, Fornai F. The effects of locus coeruleus and norepinephrine in methamphetamine toxicity. Curr Neuropharmacol 2013; 11:80-94. [PMID: 23814540 PMCID: PMC3580794 DOI: 10.2174/157015913804999522] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 07/25/2012] [Accepted: 08/08/2012] [Indexed: 12/03/2022] Open
Abstract
The activity of locus coeruleus (LC) neurons has been extensively investigated in a variety of behavioural states. In fact this norepinephrine (NE)-containing nucleus modulates many physiological and pathological conditions including the sleep-waking cycle, movement disorders, mood alterations, convulsive seizures, and the effects of drugs such as psychostimulants and opioids. This review focuses on the modulation exerted by central NE pathways on the behavioural and neurotoxic effects produced by the psychostimulant methamphetamine, essentially the modulation of the activity of mesencephalic dopamine (DA) neurons. In fact, although NE in itself mediates some behavioural effects induced by methamphetamine, NE modulation of DA release is pivotal for methamphetamine-induced behavioural states and neurotoxicity. These interactions are discussed on the basis of the state of the art of the functional neuroanatomy of central NE- and DA systems. Emphasis is given to those brain sites possessing a remarkable overlapping of both neurotransmitters.
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Affiliation(s)
- Michela Ferrucci
- Department of Human Morphology and Applied Biology, University of Pisa, Pisa, Italy
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22
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Schroeder JP, Alisha Epps S, Grice TW, Weinshenker D. The selective dopamine β-hydroxylase inhibitor nepicastat attenuates multiple aspects of cocaine-seeking behavior. Neuropsychopharmacology 2013; 38:1032-8. [PMID: 23303068 PMCID: PMC3629392 DOI: 10.1038/npp.2012.267] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although norepinephrine (NE) does not typically modulate cocaine self-administration under traditional schedules of reinforcement, it is required for different inducers of the reinstatement of cocaine-seeking behavior via activation of multiple adrenergic receptor subtypes. We predicted that blockade of NE synthesis would attenuate all known modalities of reinstatement and showed previously that the selective dopamine β-hydroxylase inhibitor, nepicastat, had no effect on either maintenance of operant cocaine self-administration maintained on a fixed-ratio 1 schedule or reinstatement of food seeking but did abolish cocaine-primed reinstatement. In the present series of studies, we first evaluated the dose-dependent effect of nepicastat (5, 50, or 100 mg/kg) on novelty-induced locomotor activity and found that it blunted exploration only at the highest dose. Next, we assessed the ability of nepicastat (50 mg/kg) to reduce breakpoint responding for cocaine on a progressive ratio schedule and reinstatement induced by drug-associated cues and stress. We found that nepicastat significantly lowered the breakpoint for cocaine, but not for regular chow or sucrose, and attenuated cue-, footshock-, and yohimbine-induced reinstatement. Combined, these results indicate that nepicastat can reduce the reinforcing properties of cocaine under a stringent schedule and can attenuate relapse-like behavior produced by cocaine, formerly cocaine-paired cues, and physiological and pharmacological stressors. Thus, nepicastat is one of those rare compounds that can reduce reinforced cocaine seeking as well as all three reinstatement modalities, while sparing exploratory behavior and natural reward seeking, making it a promising pharmacotherapy for cocaine addiction.
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Affiliation(s)
- Jason P Schroeder
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - S Alisha Epps
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - Taylor W Grice
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA,Department of Human Genetics, Emory University School of Medicine, Whitehead 301, 615 Michael Street, Atlanta, GA 30322, USA, Tel: +1 404 727 3106, Fax 1 404 727 3949, E-mail:
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23
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Gaval-Cruz M, Liles LC, Iuvone PM, Weinshenker D. Chronic inhibition of dopamine β-hydroxylase facilitates behavioral responses to cocaine in mice. PLoS One 2012; 7:e50583. [PMID: 23209785 PMCID: PMC3507785 DOI: 10.1371/journal.pone.0050583] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 10/23/2012] [Indexed: 11/19/2022] Open
Abstract
The anti-alcoholism medication, disulfiram (Antabuse), decreases cocaine use in humans regardless of concurrent alcohol consumption and facilitates cocaine sensitization in rats, but the functional targets are unknown. Disulfiram inhibits dopamine β-hydroxylase (DBH), the enzyme that converts dopamine (DA) to norepinephrine (NE) in noradrenergic neurons. The goal of this study was to test the effects of chronic genetic or pharmacological DBH inhibition on behavioral responses to cocaine using DBH knockout (Dbh −/−) mice, disulfiram, and the selective DBH inhibitor, nepicastat. Locomotor activity was measured in control (Dbh +/−) and Dbh −/− mice during a 5 day regimen of saline+saline, disulfiram+saline, nepicastat+saline, saline+cocaine, disulfiram+cocaine, or nepicastat+cocaine. After a 10 day withdrawal period, all groups were administered cocaine, and locomotor activity and stereotypy were measured. Drug-naïve Dbh −/− mice were hypersensitive to cocaine-induced locomotion and resembled cocaine-sensitized Dbh +/− mice. Chronic disulfiram administration facilitated cocaine-induced locomotion in some mice and induced stereotypy in others during the development of sensitization, while cocaine-induced stereotypy was evident in all nepicastat-treated mice. Cocaine-induced stereotypy was profoundly increased in the disulfiram+cocaine, nepicastat+cocaine, and nepicastat+saline groups upon cocaine challenge after withdrawal in Dbh +/− mice. Disulfiram or nepicastat treatment had no effect on behavioral responses to cocaine in Dbh −/− mice. These results demonstrate that chronic DBH inhibition facilitates behavioral responses to cocaine, although different methods of inhibition (genetic vs. non-selective inhibitor vs. selective inhibitor) enhance qualitatively different cocaine-induced behaviors.
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Affiliation(s)
- Meriem Gaval-Cruz
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Larry Cameron Liles
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Paul Michael Iuvone
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
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24
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Devoto P, Flore G, Saba P, Cadeddu R, Gessa GL. Disulfiram stimulates dopamine release from noradrenergic terminals and potentiates cocaine-induced dopamine release in the prefrontal cortex. Psychopharmacology (Berl) 2012; 219:1153-64. [PMID: 21863234 DOI: 10.1007/s00213-011-2447-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 08/08/2011] [Indexed: 10/17/2022]
Abstract
RATIONALE Disulfiram efficacy in treatment of cocaine addiction is attributed to the inhibition of dopamine-β-hydroxylase and reduction in brain noradrenaline (NA)/dopamine (DA) ratio. OBJECTIVES Using microdialysis, we investigated if disulfiram causes DA release from noradrenergic terminals and modifies cocaine-induced DA release. RESULTS Disulfiram reduced extracellular NA in the medial prefrontal (mPF) cortex, occipital cortex, accumbens and caudate nuclei, while it markedly increased DA not only in mPF but also in the occipital cortex, despite its scanty dopaminergic afferences, and modestly increased DA in the accumbens and caudate nuclei, despite their dense dopaminergic innervation. Disulfiram-induced DA accumulation was reversed in both cortices by tetrodotoxin infusion and by systemic administration of the α(2)-adrenoceptor agonist clonidine, but was not modified by the α(2)-adrenoceptor antagonist RS 79948 or the D(2)-like agonist quinpirole. Disulfiram prevented cocaine-induced NA release in the mPF cortex and nucleus accumbens, potentiated cocaine-induced DA release in the mPF cortex but failed to modify cocaine effect in the nucleus accumbens. DA release induced by disulfiram-cocaine combination in the mPF cortex was prevented by clonidine but not by quinpirole. CONCLUSIONS We suggested that disulfiram, by removing NA-mediated inhibitory control on noradrenergic terminals, causes an unrestrained cocaine-induced DA release from those terminals in the mPF cortex. In the accumbens and caudate nuclei, "allogenic" DA concentration might be clouded by DA originated from dopaminergic terminals. The possible role of "allogenic" DA in disulfiram ability to prevent stress-induced reinstatement of cocaine seeking is discussed.
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Affiliation(s)
- Paola Devoto
- Department of Neuroscience, University of Cagliari, Monserrato, Italy.
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Kuwayama K, Tsujikawa K, Miyaguchi H, Kanamori T, Iwata YT, Inoue H. Distribution measurement of amphetamine-type stimulants in organs using micropulverized extraction and liquid chromatography/tandem mass spectrometry to complement drug distribution using mass spectrometry imaging. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:2397-2406. [PMID: 21910286 DOI: 10.1002/rcm.5145] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Amphetamine-type stimulants (ATS) such as methamphetamine are widely abused and can cause toxic effects in the body. In this study, a simple and accurate analytical method for distribution measurement of drugs in organs was developed to visualize localization of ATS in organs and to complement drug distribution by mass spectrometry imaging (MSI). The brain, liver and kidney from rats to which ATS had been administered were segmented into blocks of 2×2×2 mm3 at -30°C. Each organ block was micropulverized with a stainless-steel bullet at -80°C. The concentrations of drugs in each block were measured by liquid chromatography/tandem mass spectrometry. The three-dimensional distribution of drugs in a whole organ was expressed using color gradation of drug concentration after reconstruction of all blocks to the original locations. The distribution was also compared with that obtained by MSI. This method enabled measurement of drug distribution in organs with simple and clean procedures and accurate quantification unlike autoradiography and MSI. The methamphetamine concentrations were different between parts in an organ, particularly in the kidney. This method could be applicable to the measurement of the distribution of compounds in various solid samples and could be used as a complementary method for the measurement of the distribution of compounds by MSI.
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Affiliation(s)
- Kenji Kuwayama
- National Research Institute of Police Science, Kashiwa, Chiba, Japan.
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Braun AA, Herring NR, Schaefer TL, Hemmerle AM, Dickerson JW, Seroogy KB, Vorhees CV, Williams MT. Neurotoxic (+)-methamphetamine treatment in rats increases brain-derived neurotrophic factor and tropomyosin receptor kinase B expression in multiple brain regions. Neuroscience 2011; 184:164-71. [PMID: 21453757 DOI: 10.1016/j.neuroscience.2011.03.045] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 03/15/2011] [Accepted: 03/22/2011] [Indexed: 10/18/2022]
Abstract
Methamphetamine (MA) is an abused stimulant which can result in cognitive deficits and monoamine depletions. Animal models of neurotoxic MA exposure show reductions in dopamine, serotonin, and their associated transporters. MA abuse can result in long-term attention, working memory, and executive function deficits in humans and deficits in route-based egocentric learning, novel object recognition, and novel odor preference in rodents. MA has also been shown to affect brain-derived neurotrophic factor (BDNF) in humans and rodents. This experiment examined the effects of a MA binge dosing regimen (10 mg/kg x 4 at 2 h intervals, s.c.) in Sprague-Dawley rats on BDNF, tropomyosin receptor kinase B (TrkB), and tyrosine hydroxylase (TH) mRNA expression, and plasma corticosterone. Tissues were collected 1, 7, and 24 h following the last MA dose. Expression of BDNF and TrkB mRNA was analyzed using in situ hybridization with cRNA probes. Frontal, parietal, and entorhinal cortical BDNF mRNA expression were increased by MA exposure at all time-points. Increases in BDNF mRNA were also seen in the hippocampal CA1, prefrontal cortex (PFC), piriform cortex, and locus coeruleus but only at specific times. TrkB mRNA expression was modified in several subregions of the hippocampus as well as in PFC and striatum. TH mRNA was increased at the 1 h time-point in the substantia nigra pars compacta with no differences noted at the other times. Corticosterone levels were increased at all three time-points. The findings suggest that BDNF and its receptor may be upregulated as a compensatory mechanism after MA exposure.
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Affiliation(s)
- A A Braun
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Research Foundation and University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
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27
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Disulfiram attenuates drug-primed reinstatement of cocaine seeking via inhibition of dopamine β-hydroxylase. Neuropsychopharmacology 2010; 35:2440-9. [PMID: 20736996 PMCID: PMC2956132 DOI: 10.1038/npp.2010.127] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The antialcoholism medication disulfiram (Antabuse) inhibits aldehyde dehydrogenase (ALDH), which results in the accumulation of acetaldehyde upon ethanol ingestion and produces the aversive 'Antabuse reaction' that deters alcohol consumption. Disulfiram has also been shown to deter cocaine use, even in the absence of an interaction with alcohol, indicating the existence of an ALDH-independent therapeutic mechanism. We hypothesized that disulfiram's inhibition of dopamine β-hydroxylase (DBH), the catecholamine biosynthetic enzyme that converts dopamine (DA) to norepinephrine (NE) in noradrenergic neurons, underlies the drug's ability to treat cocaine dependence. We tested the effects of disulfiram on cocaine and food self-administration behavior and drug-primed reinstatement of cocaine seeking in rats. We then compared the effects of disulfiram with those of the selective DBH inhibitor, nepicastat. Disulfiram, at a dose (100 mg/kg, i.p.) that reduced brain NE by ∼40%, did not alter the response for food or cocaine on a fixed ratio 1 schedule, whereas it completely blocked cocaine-primed (10 mg/kg, i.p.) reinstatement of drug seeking following extinction. A lower dose of disulfiram (10 mg/kg) that did not reduce NE had no effect on cocaine-primed reinstatement. Nepicastat recapitulated the behavioral effects of disulfiram (100 mg/kg) at a dose (50 mg/kg, i.p.) that produced a similar reduction in brain NE. Food-primed reinstatement of food seeking was not impaired by DBH inhibition. Our results suggest that disulfiram's efficacy in the treatment of cocaine addiction is associated with the inhibition of DBH and interference with the ability of environmental stimuli to trigger relapse.
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28
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Thomas DM, Angoa Pérez M, Francescutti-Verbeem DM, Shah MM, Kuhn DM. The role of endogenous serotonin in methamphetamine-induced neurotoxicity to dopamine nerve endings of the striatum. J Neurochem 2010; 115:595-605. [PMID: 20722968 DOI: 10.1111/j.1471-4159.2010.06950.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methamphetamine (METH) is a neurotoxic drug of abuse that damages the dopamine (DA) neuronal system in a highly delimited manner. The brain structure most affected by METH is the striatum where long-term DA depletion and microglial activation are maximal. Endogenous DA has been implicated as a critical participant in METH-induced neurotoxicity, most likely as a substrate for non-enzymatic oxidation by METH-generated reactive oxygen species. The striatum is also extensively innervated by serotonin (5HT) nerve endings and this neurochemical system is modified by METH in much the same manner as seen in DA nerve endings (i.e., increased release of 5HT, loss of function in tryptophan hydroxylase and the serotonin transporter, long-term depletion of 5HT stores). 5HT can also be modified by reactive oxygen species to form highly reactive species that damage neurons but its role in METH neurotoxicity has not been assessed. Increases in 5HT levels with 5-hydroxytryptophan do not change METH-induced neurotoxicity to the DA nerve endings as revealed by reductions in DA, tyrosine hydroxylase and dopamine transporter levels. Partial reductions in 5HT with p-chlorophenylalanine are without effect on METH toxicity, despite the fact that p-chlorophenylalanine largely prevents METH-induced hyperthermia. Mice lacking the gene for brain tryptophan hydroxylase 2 are devoid of brain 5HT and respond to METH in the same manner as wild-type controls, despite showing enhanced drug-induced hyperthermia. Taken together, the present results indicate that endogenous 5HT does not appear to play a role in METH-induced damage to DA nerve endings of the striatum.
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Affiliation(s)
- David M Thomas
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan, USA.
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29
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Sora I, Li B, Igari M, Hall FS, Ikeda K. Transgenic mice in the study of drug addiction and the effects of psychostimulant drugs. Ann N Y Acad Sci 2010; 1187:218-46. [PMID: 20201856 DOI: 10.1111/j.1749-6632.2009.05276.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The first transgenic models used to study addiction were based upon a priori assumptions about the importance of particular genes in addiction, including the main target molecules of morphine, amphetamine, and cocaine. This consequently emphasized the importance of monoamine transporters, opioid receptors, and monoamine receptors in addiction. Although the effects of opiates were largely eliminated by mu opioid receptor gene knockout, the case for psychostimulants was much more complex. Research using transgenic models supported the idea of a polygenic basis for psychostimulant effects and has associated particular genes with different behavioral consequences of psychostimulants. Phenotypic analysis of transgenic mice, especially gene knockout mice, has been instrumental in identifying the role of specific molecular targets of addictive drugs in their actions. In this article, we summarize studies that have provided insight into the polygenic determination of drug addiction phenotypes in ways that are not possible with other methods, emphasizing research into the effects of psychostimulant drugs in gene knockouts of the monoamine transporters and monoamine receptors.
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Affiliation(s)
- Ichiro Sora
- Department of Biological Psychiatry, Tohoku University Graduate School of Medicine, Sendai, Japan.
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30
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Gaval-Cruz M, Weinshenker D. mechanisms of disulfiram-induced cocaine abstinence: antabuse and cocaine relapse. Mol Interv 2009; 9:175-87. [PMID: 19720750 PMCID: PMC2861803 DOI: 10.1124/mi.9.4.6] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The anti-alcoholism drug disulfiram (Antabuse), which is an inhibitor of aldehyde dehydrogenase, induces an aversive reaction to alcohol consumption and thereby helps patients reduce alcohol intake. Recent clinical trials, initiated to investigate whether disulfiram could be used to treat individuals who abuse both alcohol and cocaine, have indicated that disulfiram effectively decreases cocaine consumption. Yet the ability of disulfiram to curb cocaine intake cannot be explained by the disruption of ethanol metabolism. Here, we synthesize clinical and animal data that point to dopamine beta-hydroxylase inhibition as a mechanism underlying the efficacy of disulfiram in the treatment of cocaine dependence.
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Affiliation(s)
- Meriem Gaval-Cruz
- Department of Human Genetics, Emory University School of Medicine, Whitehead 301, 615 Michael St, Atlanta, GA 30322, USA
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31
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Current world literature. Addictive disorder. Curr Opin Psychiatry 2009; 22:331-6. [PMID: 19365188 DOI: 10.1097/yco.0b013e32832ae253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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32
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Gilsbach R, Röser C, Beetz N, Brede M, Hadamek K, Haubold M, Leemhuis J, Philipp M, Schneider J, Urbanski M, Szabo B, Weinshenker D, Hein L. Genetic dissection of alpha2-adrenoceptor functions in adrenergic versus nonadrenergic cells. Mol Pharmacol 2009; 75:1160-70. [PMID: 19251826 DOI: 10.1124/mol.109.054544] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Alpha(2)-adrenoceptors mediate diverse functions of the sympathetic system and are targets for the treatment of cardiovascular disease, depression, pain, glaucoma, and sympathetic activation during opioid withdrawal. To determine whether alpha(2)-adrenoceptors on adrenergic neurons or alpha(2)-adrenoceptors on nonadrenergic neurons mediate the physiological and pharmacological responses of alpha(2)-agonists, we used the dopamine beta-hydroxylase (Dbh) promoter to drive expression of alpha(2A)-adrenoceptors exclusively in noradrenergic and adrenergic cells of transgenic mice. Dbh-alpha(2A) transgenic mice were crossed with double knockout mice lacking both alpha(2A)- and alpha(2C)-receptors to generate lines with selective expression of alpha(2A)-autoreceptors in adrenergic cells. These mice were subjected to a comprehensive phenotype analysis and compared with wild-type mice, which express alpha(2A)- and alpha(2C)-receptors in both adrenergic and nonadrenergic cells, and alpha(2A)/alpha(2C) double-knockout mice, which do not express these receptors in any cell type. We were surprised to find that only a few functions previously ascribed to alpha(2)-adrenoceptors were mediated by receptors on adrenergic neurons, including feedback inhibition of norepinephrine release from sympathetic nerves and spontaneous locomotor activity. Other agonist effects, including analgesia, hypothermia, sedation, and anesthetic-sparing, were mediated by alpha(2)-receptors in nonadrenergic cells. In dopamine beta-hydroxylase knockout mice lacking norepinephrine, the alpha(2)-agonist medetomidine still induced a loss of the righting reflex, confirming that the sedative effect of alpha(2)-adrenoceptor stimulation is not mediated via autoreceptor-mediated inhibition of norepinephrine release. The present study paves the way for a revision of the current view of the alpha(2)-adrenergic receptors, and it provides important new considerations for future drug development.
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Affiliation(s)
- Ralf Gilsbach
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany
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33
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Cassano T, Gaetani S, Morgese MG, Macheda T, Laconca L, Dipasquale P, Taltavull J, Shippenberg TS, Cuomo V, Gobbi G. Monoaminergic changes in locus coeruleus and dorsal raphe nucleus following noradrenaline depletion. Neurochem Res 2009; 34:1417-26. [PMID: 19229609 DOI: 10.1007/s11064-009-9928-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Accepted: 02/04/2009] [Indexed: 12/19/2022]
Abstract
The goal of our study was to assess the monoaminergic changes in locus coeruleus (LC) and dorsal raphe nucleus (DRN) following noradrenaline (NA) depletion. Seven days after a single N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) intraperitoneal administration in mice, we observed a decrease of NA in both the LC and DRN, as well as in prefrontal cortex (PFC) and hippocampus (HIPP). Moreover, an increase of serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) was detected at LC level, while no change was found in DRN. DSP-4 also caused a significant decrease of dopamine (DA) tissue content in HIPP and DRN, without affecting the LC and the PFC. A decrease of DA metabolite, homovanillic acid (HVA), was found in the DRN of NA-depleted mice. These results highlight that the neurotoxic action of DSP-4 is not restricted to LC terminal projections but also involves NA depletion at the cell body level, where it is paralleled by adaptive changes in both serotonergic and dopaminergic systems.
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Affiliation(s)
- Tommaso Cassano
- Department of Biomedical Sciences, University of Foggia, Viale Luigi Pinto, 1, 71100 Foggia, Italy.
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34
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Fowler JS, Volkow ND, Logan J, Alexoff D, Telang F, Wang GJ, Wong C, Ma Y, Kriplani A, Pradhan K, Schlyer D, Jayne M, Hubbard B, Carter P, Warner D, King P, Shea C, Xu Y, Muench L, Apelskog K. Fast uptake and long-lasting binding of methamphetamine in the human brain: comparison with cocaine. Neuroimage 2008; 43:756-63. [PMID: 18708148 DOI: 10.1016/j.neuroimage.2008.07.020] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2008] [Revised: 06/21/2008] [Accepted: 07/05/2008] [Indexed: 11/26/2022] Open
Abstract
Methamphetamine is one of the most addictive and neurotoxic drugs of abuse. It produces large elevations in extracellular dopamine in the striatum through vesicular release and inhibition of the dopamine transporter. In the U.S. abuse prevalence varies by ethnicity with very low abuse among African Americans relative to Caucasians, differentiating it from cocaine where abuse rates are similar for the two groups. Here we report the first comparison of methamphetamine and cocaine pharmacokinetics in brain between Caucasians and African Americans along with the measurement of dopamine transporter availability in striatum. Methamphetamine's uptake in brain was fast (peak uptake at 9 min) with accumulation in cortical and subcortical brain regions and in white matter. Its clearance from brain was slow (except for white matter which did not clear over the 90 min) and there was no difference in pharmacokinetics between Caucasians and African Americans. In contrast cocaine's brain uptake and clearance were both fast, distribution was predominantly in striatum and uptake was higher in African Americans. Among individuals, those with the highest striatal (but not cerebellar) methamphetamine accumulation also had the highest dopamine transporter availability suggesting a relationship between METH exposure and DAT availability. Methamphetamine's fast brain uptake is consistent with its highly reinforcing effects, its slow clearance with its long-lasting behavioral effects and its widespread distribution with its neurotoxic effects that affect not only striatal but also cortical and white matter regions. The absence of significant differences between Caucasians and African Americans suggests that variables other than methamphetamine pharmacokinetics and bioavailability account for the lower abuse prevalence in African Americans.
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Affiliation(s)
- Joanna S Fowler
- Medical Department, Brookhaven National Laboratory, Upton, NY 11973, USA.
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