1
|
Ma S, Zhong H, Liu X, Wang L. Spatial Distribution of Neurons Expressing Single, Double, and Triple Molecular Characteristics of Glutamatergic, Dopaminergic, or GABAergic Neurons in the Mouse Ventral Tegmental Area. J Mol Neurosci 2023; 73:345-362. [PMID: 37243808 DOI: 10.1007/s12031-023-02121-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/16/2023] [Indexed: 05/29/2023]
Abstract
The ventral tegmental area (VTA) is a heterogeneous midbrain area that plays a significant role in diverse neural processes such as reward, aversion, and motivation. The VTA contains three main neuronal populations, namely, dopamine (DA), γ-aminobutyric acid (GABA), and glutamate neurons, but some neurons exhibit combinatorial molecular characteristics of dopaminergic, GABAergic, or glutamatergic neurons. However, little information is available regarding detailed distribution of neurons with single, double, and triple molecular characteristics of glutamatergic, dopaminergic, or GABAergic neurons in mice. We present a topographical distribution map of three main neuronal populations expressing a single molecular characteristic of dopaminergic, GABAergic, or glutamatergic neurons, and four neuronal populations co-expressing double or triple molecular characteristics in combinatorial manners, in the mouse VTA, following analysis of triple fluorescent in situ hybridization for the simultaneous detection of tyrosine hydroxylase (TH, marker for dopaminergic neurons), vesicular glutamate transporter 2 (VGLUT2, marker for glutamatergic neurons), and glutamic acid decarboxylase 2 (GAD2, marker for GABAergic neurons) mRNA. We found that the vast majority of neurons expressed a single type of mRNA, and these neurons were intermingled with neurons co-expressing double or triple combinations of VGLUT2, TH, or GAD2 in the VTA. These seven neuronal populations were differentially distributed in the VTA sub-nuclei across the rostro-caudal and latero-medial axes. This histochemical study will lead to a deeper understanding of the complexity of neuronal molecular characteristics in different VTA sub-nuclei, and potentially facilitate clarification of diverse functions of the VTA.
Collapse
Affiliation(s)
- Shaohua Ma
- Shenzhen Key Laboratory of Neuropsychiatric Modulation, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Hao Zhong
- Shenzhen Key Laboratory of Neuropsychiatric Modulation, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Xuemei Liu
- Shenzhen Key Laboratory of Neuropsychiatric Modulation, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Liping Wang
- Shenzhen Key Laboratory of Neuropsychiatric Modulation, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- CAS Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
- Guangdong Provincial Key Laboratory of Brain Connectome and Behavior, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| |
Collapse
|
2
|
Nashed MG, Waye S, Hasan SMN, Nguyen D, Wiseman M, Zhang J, Lau H, Dinesh OC, Raymond R, Greig IR, Bambico FR, Nobrega JN. Antidepressant activity of pharmacological and genetic deactivation of the small-conductance calcium-activated potassium channel subtype-3. Psychopharmacology (Berl) 2022; 239:253-266. [PMID: 34982171 DOI: 10.1007/s00213-021-06045-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 12/13/2021] [Indexed: 11/25/2022]
Abstract
RATIONALE The voltage-insensitive, small-conductance calcium-activated potassium (SK) channel is a key regulator of neuronal depolarization and is implicated in the pathophysiology of depressive disorders. OBJECTIVE We ascertained whether the SK channel is impaired in the chronic unpredictable stress (CUS) model and whether it can serve as a molecular target of antidepressant action. METHODS We assessed the depressive-like behavioral phenotype of CUS-exposed rats and performed post-mortem SK channel binding and activity-dependent zif268 mRNA analyses on their brains. To begin an assessment of SK channel subtypes involved, we examined the effects of genetic and pharmacological inhibition of the SK3 channel using conditional knockout mice and selective SK3 channel negative allosteric modulators (NAMs). RESULTS We found that [125I]apamin binding to SK channels is increased in the prefrontal cortex and decreased in the hippocampus, an effect that was associated with reciprocal levels of zif268 mRNA transcripts indicating abnormal regional cell activity in this model. We found that genetic and pharmacological manipulations significantly decreased immobility in the forced swim test without altering general locomotor activity, a hallmark of antidepressant-like activity. CONCLUSIONS Taken together, these findings link depression-related neural and behavioral pathophysiology with abnormal SK channel functioning and suggest that this can be reversed by the selective inhibition of SK3 channels.
Collapse
Affiliation(s)
- Mina G Nashed
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| | - Shannon Waye
- Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland & Labrador, A1B 3X9, Canada
| | - S M Nageeb Hasan
- Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland & Labrador, A1B 3X9, Canada
| | - Diana Nguyen
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| | - Micaela Wiseman
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| | - Jing Zhang
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| | - Harry Lau
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| | - O Chandani Dinesh
- Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland & Labrador, A1B 3X9, Canada
| | - Roger Raymond
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| | - Iain R Greig
- Institute of Medical Sciences, University of Aberdeen, King's College, Aberdeen, AB25 2ZD, Scotland
| | - Francis Rodriguez Bambico
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada. .,Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland & Labrador, A1B 3X9, Canada.
| | - José N Nobrega
- Behavioural Neurobiology Laboratory, Research Imaging Center, Centre for Addiction and Mental Health (CAMH), Toronto, ON, M5T 1R8, Canada
| |
Collapse
|
3
|
Kim W, Chung C. Brain-wide cellular mapping of acute stress-induced activation in male and female mice. FASEB J 2021; 35:e22041. [PMID: 34780680 DOI: 10.1096/fj.202101287r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 10/14/2021] [Accepted: 10/29/2021] [Indexed: 11/11/2022]
Abstract
Mood disorders are more prevalent and often reported to be more severe in women; however, little is known about the underlying mechanisms of this sexual prevalence. To gain insight into the functional differences in female brains in response to stress, we systemically compared brain activation in male and female C57BL/6N mice after acute stress exposure. We measured c-Fos expression levels in 18 brain areas related to stress responses after a 3-h long restraint stress and found that activation was sexually dimorphic in several brain areas, including the nucleus accumbens, ventral tegmental area, nucleus reuniens, and medial part of the lateral habenula. Moreover, stress-activated a substantial number of cells in the medial prefrontal cortex, amygdala, and lateral part of the lateral habenula; however, the levels of activation were comparable in males and females, suggesting that the core stress responding machineries are largely shared. Pearson correlation analysis revealed several interesting connections between the analyzed areas that are implicated in stress responses and depression. Overall, stress strengthened intra-circuitries in the hippocampus, amygdala, and prefrontal cortex in female mice, whereas more longer-range connections were highlighted in stressed male mice. Our study provides a highly valuable neuroanatomical framework for investigating the circuit mechanism underlying the higher vulnerability to depression in women.
Collapse
Affiliation(s)
- Woonhee Kim
- Department of Biological Sciences, Konkuk University, Seoul, South Korea
| | - ChiHye Chung
- Department of Biological Sciences, Konkuk University, Seoul, South Korea
| |
Collapse
|
4
|
Waye SC, Dinesh OC, Hasan SN, Conway JD, Raymond R, Nobrega JN, Blundell J, Bambico FR. Antidepressant action of transcranial direct current stimulation in olfactory bulbectomised adolescent rats. J Psychopharmacol 2021; 35:1003-1016. [PMID: 33908307 DOI: 10.1177/02698811211000765] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Antidepressant drugs in adolescent depression are sometimes mired by efficacy issues and paradoxical effects. Transcranial direct current stimulation (tDCS) could represent an alternative. AIMS/METHODS We tested the antidepressant action of prefrontal tDCS and paroxetine (20 mg/kg, intraperitoneal) in olfactory bulbectomised (OBX) adolescent rats. Using enzyme-linked immunosorbent assays and in situ hybridisation, we examined treatment-induced changes in plasma brain-derived neurotrophic factor (BDNF) and brain serotonin transporter (SERT) and 5-HT-1A mRNA. RESULTS OBX-induced anhedonia-like reductions in sucrose preference (SP) correlated with open field (OF) hyperactivity. These were accompanied by decreased zif268 mRNA in the piriform/amygdalopiriform transition area, and increased zif268 mRNA in the hypothalamus. Acute paroxetine (2 days) led to a profound SP reduction, an effect blocked by combined tDCS-paroxetine administration. Chronic (14 days) tDCS attenuated hyperlocomotion and its combination with paroxetine blocked OBX-induced SP reduction. Correlations among BDNF, SP and hyperlocomotion scores were altered by OBX but were normalised by tDCS-paroxetine co-treatment. In the brain, paroxetine increased zif268 mRNA in the hippocampal CA1 subregion and decreased it in the claustrum. This effect was blocked by tDCS co-administration, which also increased zif268 in CA2. tDCS-paroxetine co-treatment had variable effects on 5-HT1A receptors and SERT mRNA. 5-HT1A receptor changes were found exclusively within depression-related parahippocampal/hippocampal subregions, and SERT changes within fear/defensive response-modulating brainstem circuits. CONCLUSION These findings point towards potential synergistic efficacies of tDCS and paroxetine in the OBX model of adolescent depression via mechanisms associated with altered expression of BDNF, 5-HT1A, SERT and zif268 in discrete corticolimbic areas.
Collapse
Affiliation(s)
- Shannon C Waye
- Department of Psychology, Memorial University of Newfoundland, St. John's, Canada
| | - O Chandani Dinesh
- Department of Psychology, Memorial University of Newfoundland, St. John's, Canada
| | - Sm Nageeb Hasan
- Department of Psychology, Memorial University of Newfoundland, St. John's, Canada
| | - Joshua D Conway
- Department of Psychology, Memorial University of Newfoundland, St. John's, Canada
| | - Roger Raymond
- Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health, Toronto, Canada
| | - José N Nobrega
- Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health, Toronto, Canada
| | - Jacqueline Blundell
- Department of Psychology, Memorial University of Newfoundland, St. John's, Canada
| | - Francis Rodriguez Bambico
- Department of Psychology, Memorial University of Newfoundland, St. John's, Canada.,Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health, Toronto, Canada
| |
Collapse
|
5
|
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.
Collapse
|
6
|
Trujillo-Villarreal LA, Romero-Díaz VJ, Marino-Martínez IA, Fuentes-Mera L, Ponce-Camacho MA, Devenyi GA, Mallar Chakravarty M, Camacho-Morales A, Garza-Villarreal EE. Maternal cafeteria diet exposure primes depression-like behavior in the offspring evoking lower brain volume related to changes in synaptic terminals and gliosis. Transl Psychiatry 2021; 11:53. [PMID: 33446642 PMCID: PMC7809040 DOI: 10.1038/s41398-020-01157-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 12/07/2020] [Accepted: 12/10/2020] [Indexed: 02/07/2023] Open
Abstract
Maternal nutritional programming by caloric exposure during pregnancy and lactation results in long-term behavioral modification in the offspring. Here, we characterized the effect of maternal caloric exposure on synaptic and brain morphological organization and its effects on depression-like behavior susceptibility in rats' offspring. Female Wistar rats were exposed to chow or cafeteria (CAF) diet for 9 weeks (pre-pregnancy, pregnancy, and lactation) and then switched to chow diet after weaning. By postnatal day 60, the male Wistar rat offspring were tested for depressive-like behavior using operational conditioning, novelty suppressed feeding, sucrose preference, and open-field test. Brain macro and microstructural morphology were analyzed using magnetic resonance imaging deformation-based morphometry (DBM) and western blot, immunohistochemistry for NMDA and AMPA receptor, synaptophysin and myelin, respectively. We found that the offspring of mothers exposed to CAF diet displayed deficient motivation showing decrease in the operant conditioning, sucrose preference, and suppressed feeding test. Macrostructural DBM analysis showed reduction in the frontomesocorticolimbic circuit volume including the nucleus accumbens (NAc), hippocampus, and prefrontal cortex. Microstructural analysis revealed reduced synaptic terminals in hippocampus and NAc, whereas increased glial fibrillary acidic protein in hippocampus and lateral hypothalamus, as well as a decrease in the hippocampal cell number and myelin reduction in the dentate gyrus and hilus, respectively. Also, offspring exhibited increase of the GluR1 and GLUR2 subunits of AMPA receptor, whereas a decrease in the mGluR2 expression in hippocampus. Our findings reveal that maternal programming might prime depression-like behavior in the offspring by modulating macro and micro brain organization of the frontomesocorticolimbic circuit.
Collapse
Affiliation(s)
- Luis A Trujillo-Villarreal
- Department of Biochemistry, College of Medicine, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
- Neurometabolism Unit, Center for Research and Development in Health Sciences, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Viktor J Romero-Díaz
- Gene therapy Unit, Center for Research and Development in Health Sciences, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Iván Alberto Marino-Martínez
- Gene therapy Unit, Center for Research and Development in Health Sciences, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Lizeth Fuentes-Mera
- Department of Biochemistry, College of Medicine, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Marco Antonio Ponce-Camacho
- Servicio de Anatomía Patológica y Citopatología. Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México
| | - Gabriel A Devenyi
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, QC, Canada
| | - M Mallar Chakravarty
- Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
- Department of Biological and Biomedical Engineering, McGill University, Montreal, Canada
| | - Alberto Camacho-Morales
- Department of Biochemistry, College of Medicine, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México.
- Neurometabolism Unit, Center for Research and Development in Health Sciences, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, México.
| | - Eduardo E Garza-Villarreal
- Instituto de Neurobiología, Universidad Nacional Autónoma de México campus Juriquilla, Queretaro, Mexico.
| |
Collapse
|
7
|
Molecular Targets of Cannabidiol in Experimental Models of Neurological Disease. Molecules 2020; 25:molecules25215186. [PMID: 33171772 PMCID: PMC7664437 DOI: 10.3390/molecules25215186] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/12/2022] Open
Abstract
Cannabidiol (CBD) is a non-psychoactive phytocannabinoid known for its beneficial effects including antioxidant and anti-inflammatory properties. Moreover, CBD is a compound with antidepressant, anxiolytic, anticonvulsant and antipsychotic effects. Thanks to all these properties, the interest of the scientific community for it has grown. Indeed, CBD is a great candidate for the management of neurological diseases. The purpose of our review is to summarize the in vitro and in vivo studies published in the last 15 years that describe the biochemical and molecular mechanisms underlying the effects of CBD and its therapeutic application in neurological diseases. CBD exerts its neuroprotective effects through three G protein coupled-receptors (adenosine receptor subtype 2A, serotonin receptor subtype 1A and G protein-coupled receptor 55), one ligand-gated ion channel (transient receptor potential vanilloid channel-1) and one nuclear factor (peroxisome proliferator-activated receptor γ). Moreover, the therapeutical properties of CBD are also due to GABAergic modulation. In conclusion, CBD, through multi-target mechanisms, represents a valid therapeutic tool for the management of epilepsy, Alzheimer’s disease, multiple sclerosis and Parkinson’s disease.
Collapse
|
8
|
Hyperexcitability of VTA dopaminergic neurons in male offspring exposed to physical or psychological prenatal stress. Prog Neuropsychopharmacol Biol Psychiatry 2020; 101:109923. [PMID: 32173457 DOI: 10.1016/j.pnpbp.2020.109923] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Revised: 03/10/2020] [Accepted: 03/11/2020] [Indexed: 02/02/2023]
Abstract
Prenatal stress (PS) exposure leads to cognitive and behavioral alterations in offspring including an increased risk of substance abuse and anxiety disorders. Signalling from dopamine (DA) neurons of the ventral tegmental area (VTA) in the mesoaccumbal and mesocortical pathways plays a vital role in drug dependency and anxiety behavior. To provide further knowledge about the changes in drug seeking behavior and anxiety behaviors in prenatally stressed mice, we conducted ex vivo investigations in VTA brain slices of adult male PS offspring to evaluate the effects of two types of PS (physical vs. psychological) on activity of DA neurons. Elevated plus maze (EPM) was used to assess anxiety-like behaviors and conditioned place preference (CPP) was used to evaluate drug reinforcing effects in mice. An increased anxiety-like behavior and preference to morphine was observed in prenatally stressed mice. PS VTA DA cells exhibited greater Ih current and a higher frequency and amplitude of sEPSCs, which were consistent with a greater degree of pre- or postsynaptic excitability of the VTA. This was confirmed by lower rheobase and lower firing thresholds in PS VTA neurons, as well as increases in spontaneous firing frequency. When taken together, these data suggest that alterations in VTA DA neurons in this mouse model of prenatal stress might be associated with later life alterations in drug seeking and anxiety-like behaviors through their role in mesocortical and mesoaccumbal pathways.
Collapse
|
9
|
Cifelli P, Ruffolo G, De Felice E, Alfano V, van Vliet EA, Aronica E, Palma E. Phytocannabinoids in Neurological Diseases: Could They Restore a Physiological GABAergic Transmission? Int J Mol Sci 2020; 21:E723. [PMID: 31979108 PMCID: PMC7038116 DOI: 10.3390/ijms21030723] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 01/19/2023] Open
Abstract
γ-Aminobutyric acid type A receptors (GABAARs) are the main inhibitory mediators in the central nervous system (CNS). GABAARs are pentameric ligand gated ion channels, and the main subunit composition is usually 2α2βγ, with various isotypes assembled within a set of 19 different subunits. The inhibitory function is mediated by chloride ion movement across the GABAARs, activated by synaptic GABA release, reducing neuronal excitability in the adult CNS. Several studies highlighted the importance of GABA-mediated transmission during neuro-development, and its involvement in different neurological and neurodevelopmental diseases, from anxiety to epilepsy. However, while it is well known how different classes of drugs are able to modulate the GABAARs function (benzodiazepines, barbiturates, neurosteroids, alcohol), up to now little is known about GABAARs and cannabinoids interaction in the CNS. Endocannabinoids and phytocannabinoids are lately emerging as a new class of promising drugs for a wide range of neurological conditions, but their safety as medication, and their mechanisms of action are still to be fully elucidated. In this review, we will focus our attention on two of the most promising molecules (Δ9-tetrahydrocannabinol; Δ9-THC and cannabidiol; CBD) of this new class of drugs and their possible mechanism of action on GABAARs.
Collapse
Affiliation(s)
| | - Gabriele Ruffolo
- IRCCS San Raffaele Pisana, 00163 Rome, Italy; (G.R.); (E.D.F.)
- Department of Physiology and Pharmacology, laboratory affiliated to Istituto Pasteur Italia, University of Rome Sapienza, 00185 Rome, Italy;
| | | | - Veronica Alfano
- Department of Physiology and Pharmacology, laboratory affiliated to Istituto Pasteur Italia, University of Rome Sapienza, 00185 Rome, Italy;
| | - Erwin Alexander van Vliet
- Amsterdam UMC, University of Amsterdam, Department of (Neuro) Pathology, 1105 Amsterdam, The Netherlands; (E.A.v.V.); (E.A.)
- Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, 1090 Amsterdam, The Netherlands
| | - Eleonora Aronica
- Amsterdam UMC, University of Amsterdam, Department of (Neuro) Pathology, 1105 Amsterdam, The Netherlands; (E.A.v.V.); (E.A.)
- Stichting Epilepsie Instellingen Nederland (SEIN), 0397 Heemstede, The Netherlands
| | - Eleonora Palma
- Department of Physiology and Pharmacology, laboratory affiliated to Istituto Pasteur Italia, University of Rome Sapienza, 00185 Rome, Italy;
| |
Collapse
|
10
|
α7 nicotinic receptor full agonist reverse basolateral amygdala hyperactivity and attenuation of dopaminergic neuron activity in rats exposed to chronic mild stress. Eur Neuropsychopharmacol 2019; 29:1343-1353. [PMID: 31615702 PMCID: PMC6934081 DOI: 10.1016/j.euroneuro.2019.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 09/06/2019] [Accepted: 09/19/2019] [Indexed: 12/19/2022]
Abstract
Neuroimaging and preclinical studies showing that nicotinic receptors (nAChR) may play a role in mood control has increased interest in targeting the cholinergic system for treatment of major depressive disorder. Indeed, modulation of nAChRs in the basolateral amygdala (BLA) are sufficient to produce an anti-immobility effect in the mouse tail suspension test. However, how α7 nAChR modulation impacts BLA neuronal activity in vivo as well as the downstream mechanisms involved in its mood-related effects are not understood. In this work, we used the unpredictable chronic mild stress (CMS) model to investigate the mechanisms underlying the antidepressant-like effect of an α7 nAChR full agonist on BLA-induced changes in dopaminergic neurotransmission. Male adult Sprague-Dawley rats were exposed to four weeks of CMS. Behavioral and electrophysiological experiments were performed within one week following stress. CMS exposure increased rats' immobility time in the forced swimming test, decreased the number of spontaneously active dopamine neurons in the ventral tegmental area and increased the firing rate of putative projection neurons in the BLA. Stress-induced behavioral and electrophysiological changes were reversed by a single systemic administration of PNU282987. In summary, our findings corroborate previous descriptions of a potential rapid antidepressant effect for the α7 nAChR full agonist. This effect appears to involve a mechanism distinct from those of classic antidepressants: normalization of BLA hyperactivity and, consequently, of DA hypofunction. These observations corroborate the role of α7 nAChR as a potential target for novel antidepressant drug development.
Collapse
|