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Kelley AM, Del Valle EJ, Zaman S, Karkhanis AN. Adolescent ethanol exposure promotes mechanical allodynia and alters dopamine transmission in the nucleus accumbens shell. Pain 2024; 165:e55-e64. [PMID: 37962155 PMCID: PMC11090756 DOI: 10.1097/j.pain.0000000000003097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 10/03/2023] [Indexed: 11/15/2023]
Abstract
ABSTRACT Excessive alcohol consumption in adolescence can disrupt neural development and may augment pain perception. Recent studies have shown that the nucleus accumbens (NAc) shell is involved in mediating pain sensitivity after peripheral inflammation in rodent models of chronic pain and alcohol use disorder. Interestingly, there have been very few studies examining the impact of chronic ethanol exposure during adolescence on pain sensitivity in adulthood. Therefore, in this project, we investigated the impact of adolescent chronic intermittent ethanol (aCIE) exposure on mechanical allodynia. Furthermore, given the involvement of the NAc shell in pain processing and chronic ethanol-mediated changes, we measured changes in accumbal dopamine kinetics during protracted withdrawal. We found that both male and female aCIE rats show mechanical allodynia during withdrawal. Furthermore, male and female aCIE rats show greater evoked tonic dopamine release, maximal rate of dopamine reuptake, and dopamine affinity to the dopamine transporter in the NAc shell compared with controls. With phasic stimulation, aCIE rats also showed greater dopamine release compared with AIR-exposed rats. Inhibition of dopamine transmission targeted in the NAc shell reversed the aCIE-associated facilitation of mechanical allodynia in both sexes. These data suggest that aCIE exposure exacerbates pain sensitivity during withdrawal in an accumbal dopamine-dependent manner.
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Affiliation(s)
- Abigail M Kelley
- Department of Psychology, Developmental Exposure to Alcohol Research Center, Binghamton University-SUNY, Binghamton, NY, United States
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2
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Agni MB, Hegde PS, Rai P, Sadananda M, K M DG. Astaxanthin and DHA Supplementation Modulates the Maternal Undernutrition-induced Impairment of Cognitive Behavior and Synaptic Plasticity in Adult Life of Offspring's -Exploring the Molecular Mechanism. Mol Neurobiol 2024:10.1007/s12035-024-04147-y. [PMID: 38578356 DOI: 10.1007/s12035-024-04147-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 03/23/2024] [Indexed: 04/06/2024]
Abstract
Maternal nutrition was recognized as a significant part of brain growth and maturation in most mammalian species. Timely intervention with suitable nutraceuticals would provide long-term health benefits. We aim to unravel the molecular mechanisms of perinatal undernutrition-induced impairments in cognition and synaptic plasticity, employing animal model based on dietary nutraceutical supplementation. We treated undernourished dams at their gestational, lactational, and at both the time point with Astaxanthin (AsX) and Docosahexaenoic acid (DHA), and their pups were used as experimental animals. We evaluated the cognitive function by subjecting the pups to behavioral tests in their adult life. In addition, we assessed the expression of genes in the hippocampus related to cognitive function and synaptic plasticity. Our results showed downregulation of Brain-derived neurotrophic factor (BDNF), Neurotrophin-3 (NT-3), cAMP response-element-binding protein (CREB), and uncoupling protein-2 (UCP2) gene expression in pups born to undernourished dams in their adult life, which AsX and DHA modulated. Maternal AsX and DHA supplementation ameliorated the undernutrition-induced learning impairment in novel object recognition (NOR) tests and partially baited radial arm maze (RAM) tasks in offspring's. The expressions of Synapsin-1 and PSD-95 decreased in perinatally undernourished groups compared to control and AsX-DHA treated groups at CA1, CA2, CA3, and DG. AsX and DHA supplementation upregulated BDNF, NT-3, CREB, and UCP2 gene expressions in perinatally undernourished rats, which are involved in intracellular signaling cascades like Ras, PI3K, and PLC. The results of our study give new insights into neuronal differentiation, survival, and plasticity, indicating that the perinatal period is the critical time for reversing maternal undernutrition-induced cognitive impairment in offspring's.
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Affiliation(s)
- Megha Bhat Agni
- Nitte (Deemed to be University), Department of Physiology, KS Hegde Medical Academy, Deralakatte, Mangalore, Karnataka, 575018, India
| | - Pramukh Subrahmanya Hegde
- Nitte (Deemed to be University), Department of Physiology, KS Hegde Medical Academy, Deralakatte, Mangalore, Karnataka, 575018, India
| | - Praveen Rai
- Nitte (Deemed to be University), Department of Infectious Diseases & Microbial Genomics, Nitte University Centre for Science Education and Research (NUCSER), Mangalore, Karnataka, 575018, India
| | - Monika Sadananda
- Biotechnology Unit, Department of Biosciences, Mangalore University, Mangalagangothri, 574199, Karnataka, India
| | - Damodara Gowda K M
- Nitte (Deemed to be University), Department of Physiology, KS Hegde Medical Academy, Deralakatte, Mangalore, Karnataka, 575018, India.
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3
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McElroy BD, Li C, McCloskey NS, Kirby LG. Sex differences in ethanol consumption and drinking despite negative consequences following adolescent social isolation stress in male and female rats. Physiol Behav 2023; 271:114322. [PMID: 37573960 PMCID: PMC10592127 DOI: 10.1016/j.physbeh.2023.114322] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 07/19/2023] [Accepted: 08/10/2023] [Indexed: 08/15/2023]
Abstract
Alcohol use disorder (AUD) is a debilitating psychiatric disorder characterized by drinking despite negative social and biological consequences. AUDs make up 71% of substance use disorders, with relapse rates as high as 80%. Current treatments stem from data conducted largely in males and fail to target the psychological distress motivating drinking in stress-vulnerable and at-risk populations. Here we employed a rat model and hypothesized that early life stress would reveal sex differences in ethanol intake and drinking despite negative consequences in adulthood. Rats were group housed or isolated postweaning to evaluate sex and stress effects on ethanol consumption in homecage drinking, self-administration (SA), and punished SA (drinking despite negative consequences) in adulthood. Stressed rats showed elevated homecage ethanol intake, an effect more pronounced in females. During SA, males were more sensitive to stress-induced elevations of drinking over time, but females drank more overall. Stressed rats, regardless of sex, responded more for ethanol than their non-stressed counterparts. Stressed females showed greater resistance to punishment-suppressed SA than stressed males, indicating a more stress-resistant drinking phenotype. Results support our hypothesis that adolescent social isolation stress enhances adult ethanol intake in a sex- and model-dependent manner with females being especially sensitive to early life stress-induced elevations in ethanol intake and punished SA in adulthood. Our findings echo the clinical literature which indicates that stress-vulnerable populations are more likely to 'self-medicate' with substances. Elucidating a potential mechanism that underlies why vulnerable populations 'self-medicate' with alcohol can lead towards developing catered pharmacotherapeutics that could reduce punishment-resistant drinking and relapse.
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Affiliation(s)
- Bryan D McElroy
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University Philadelphia, PA, 19140, United States of America.
| | - Chen Li
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University Philadelphia, PA, 19140, United States of America
| | - Nicholas S McCloskey
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University Philadelphia, PA, 19140, United States of America
| | - Lynn G Kirby
- Center for Substance Abuse Research, Lewis Katz School of Medicine at Temple University Philadelphia, PA, 19140, United States of America
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4
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Cavieres G, Bozinovic F, Bogdanovich JM, Rivera DS. Impact of prolonged chronic social isolation stress on behavior and multifractal complexity of metabolic rate in Octodon degus. Front Behav Neurosci 2023; 17:1239157. [PMID: 37928446 PMCID: PMC10622977 DOI: 10.3389/fnbeh.2023.1239157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/25/2023] [Indexed: 11/07/2023] Open
Abstract
Social interaction can improve animal performance through the prevention of stress-related events, the provision of security, and the enhancement of reproductive output and survival. We investigated the effects of prolonged chronic social isolation stress on behavioral, cognitive, and physiological performance in the social, long-lived rodent Octodon degus. Degu pups were separated into two social stress treatments: control (CTRL) and chronically isolated (CI) individuals from post-natal and post-weaning until adulthood. We quantified anxiety-like behavior and cognitive performance with a battery of behavioral tests. Additionally, we measured their basal metabolic rate (BMR) and analyzed the multifractal properties of the oxygen consumption time series using Multifractal Detrended Fluctuation Analysis, a well-known method for assessing the fractal characteristics of biological signals. Our results showed that CI induced a significant increase in anxiety-like behaviors and led to a reduction in social and working memory in male degus. In addition, CI-treated degus reduced the multifractal complexity of BMR compared to CTRL, which implies a decrease in the ability to respond to environmental stressors and, as a result, an unhealthy state. In contrast, we did not observe significant effects of social stress on BMR. Multivariate analyses showed a clear separation of behavior and physiological variables into two clusters, corresponding to CI and CTRL degus. This study provides novel insights into the effects of prolonged chronic social isolation stress on behavior, cognitive performance, and metabolic complexity in this rodent animal model. To the best of our knowledge, it is the first study to integrate cognitive-behavioral performance and multifractal dynamics of a physiological signal in response to prolonged social isolation. These findings highlight the importance of social interactions for the well-being and overall performance of social animals.
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Affiliation(s)
- Grisel Cavieres
- Departamento de Zoología, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
- Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Francisco Bozinovic
- Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - José Miguel Bogdanovich
- Center of Applied Ecology and Sustainability (CAPES), Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela S. Rivera
- GEMA Center for Genomics, Ecology and Environment, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
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5
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Heng V, Zigmond M, Smeyne RJ. Neuroanatomical and neurochemical effects of prolonged social isolation in adult mice. Front Neuroanat 2023; 17:1190291. [PMID: 37662476 PMCID: PMC10471319 DOI: 10.3389/fnana.2023.1190291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 07/31/2023] [Indexed: 09/05/2023] Open
Abstract
Introduction As social animals, our health depends in part on interactions with other human beings. Yet millions suffer from chronic social isolation, including those in nursing/assisted living facilities, people experiencing chronic loneliness as well as those in enforced isolation within our criminal justice system. While many historical studies have examined the effects of early isolation on the brain, few have examined its effects when this condition begins in adulthood. Here, we developed a model of adult isolation using mice (C57BL/6J) born and raised in an enriched environment. Methods From birth until 4 months of age C57BL/6J mice were raised in an enriched environment and then maintained in that environment or moved to social isolation for 1 or 3 months. We then examined neuronal structure and catecholamine and brain derived neurotrophic factor (BDNF) levels from different regions of the brain, comparing animals from social isolation to enriched environment controls. Results We found significant changes in neuronal volume, dendritic length, neuronal complexity, and spine density that were dependent on brain region, sex, and duration of the isolation. Isolation also altered dopamine in the striatum and serotonin levels in the forebrain in a sex-dependent manner, and also reduced levels of BDNF in the motor cortex and hippocampus of male but not female mice. Conclusion These studies show that isolation that begins in adulthood imparts a significant change on the homeostasis of brain structure and chemistry.
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Affiliation(s)
- Vibol Heng
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, United States
| | - Michael Zigmond
- Department of Neurology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Richard Jay Smeyne
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA, United States
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Wells AC, Lotfipour S. Prenatal nicotine exposure during pregnancy results in adverse neurodevelopmental alterations and neurobehavioral deficits. ADVANCES IN DRUG AND ALCOHOL RESEARCH 2023; 3:11628. [PMID: 38389806 PMCID: PMC10880762 DOI: 10.3389/adar.2023.11628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/28/2023] [Indexed: 02/24/2024]
Abstract
Maternal tobacco use and nicotine exposure during pregnancy have been associated with adverse birth outcomes in infants and can lead to preventable pregnancy complications. Exposure to nicotine and other compounds in tobacco and electronic cigarettes (e-cigarettes) has been shown to increases the risk of miscarriage, prematurity, stillbirth, low birth weight, perinatal morbidity, and sudden infant death syndrome (SIDS). Additionally, recent data provided by clinical and pre-clinical research demonstrates that nicotine exposure during pregnancy may heighten the risk for adverse neurodevelopmental disorders such as Attention-Deficit Hyperactivity (ADHD), anxiety, and depression along with altering the infants underlying brain circuitry, response to neurotransmitters, and brain volume. In the United States, one in 14 women (7.2%) reported to have smoked cigarettes during their pregnancy with the global prevalence of smoking during pregnancy estimated to be 1.7%. Approximately 1.1% of women in the United States also reported to have used e-cigarettes during the last 3 months of pregnancy. Due to the large percentage of women utilizing nicotine products during pregnancy in the United States and globally, this review seeks to centralize pre-clinical and clinical studies focused on the neurobehavioral and neurodevelopmental complications associated with prenatal nicotine exposure (PNE) such as alterations to the hypothalamic-pituitary-adrenal (HPA) axis and brain regions such as the prefrontal cortex (PFC), ventral tegmental area (VTA), nucleus accumbens (NA), hippocampus, and caudate as well as changes to nAChR and cholinergic receptor signaling, long-term drug seeking behavior following PNE, and other related developmental disorders. Current literature analyzing the association between PNE and the risk for offspring developing schizophrenia, attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), anxiety, and obesity will also be discussed.
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Affiliation(s)
- Alicia C Wells
- School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Shahrdad Lotfipour
- School of Medicine, University of California, Irvine, Irvine, CA, United States
- Department of Emergency Medicine, Pharmaceutical Sciences, Pathology and Laboratory Medicine, University of California, Irvine, Irvine, CA, United States
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7
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Davari S, D'Costa N, Ramezan R, Mielke JG. Chronic Early-Life Social Isolation Enhances Spatial Memory in Male and Female Rats. Behav Brain Res 2023; 447:114433. [PMID: 37037406 DOI: 10.1016/j.bbr.2023.114433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/30/2023] [Accepted: 04/07/2023] [Indexed: 04/12/2023]
Abstract
Social adversity during childhood and adolescence can alter brain development in ways that may increase the likelihood of many prominent mental illnesses. To determine the underlying mechanisms, several animal models have been developed, such as Chronic Early-Life Social Isolation (CELSI), which sees rats isolated for several weeks after weaning. Although such a paradigm does cause many consistent changes in adult behaviour, one area where uncertainty exists concerns its effect upon hippocampal-dependent learning and memory. To help sort out how CELSI affects spatial learning and memory, male and female siblings from 15 Sprague-Dawley rat litters were stratified by sex and then randomly assigned to either group-housing (3 animals/cage), or social isolation (1 animal/cage) for 7 weeks. Spatial learning and memory were then tested over 5 days using the Morris water maze. Next, the animals were euthanised, and stress-sensitive biometrics, including serum corticosterone levels, were collected. Lastly, to determine whether CELSI affected neural cell density, the expression of key neuronal and glial proteins (such as PSD-95 and GFAP, respectively) was assessed in isolated hippocampal tissue using immunoblotting. Notably, both male and female rats that had experienced post-weaning social isolation displayed stronger spatial learning and memory abilities than their group-housed counterparts. As well, socially isolated male rats exhibited a clear increase in expression of PSD-95. However, housing condition did not seem to affect either stress-sensitive biometrics, or hippocampal GFAP expression. Our results support the possibility that CELSI may enhance some aspects of hippocampal-dependent behaviour in a fashion similar among male and female rats.
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Affiliation(s)
- Saeideh Davari
- School of Public Health Sciences, University of Waterloo, Waterloo, ON, Canada
| | - Nicole D'Costa
- School of Public Health Sciences, University of Waterloo, Waterloo, ON, Canada
| | - Reza Ramezan
- Department of Statistics and Actuarial Science, University of Waterloo, Waterloo, ON, Canada
| | - John G Mielke
- School of Public Health Sciences, University of Waterloo, Waterloo, ON, Canada.
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8
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Mancini GF, Meijer OC, Campolongo P. Stress in adolescence as a first hit in stress-related disease development: Timing and context are crucial. Front Neuroendocrinol 2023; 69:101065. [PMID: 37001566 DOI: 10.1016/j.yfrne.2023.101065] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 03/22/2023] [Accepted: 03/25/2023] [Indexed: 04/06/2023]
Abstract
The two-hit stress model predicts that exposure to stress at two different time-points in life may increase or decrease the risk of developing stress-related disorders later in life. Most studies based on the two-hit stress model have investigated early postnatal stress as the first hit with adult stress as the second hit. Adolescence, however, represents another highly sensitive developmental window during which exposure to stressful events may affect programming outcomes following exposure to stress in adulthood. Here, we discuss the programming effects of different types of stressors (social and nonsocial) occurring during adolescence (first hit) and how such stressors affect the responsiveness toward an additional stressor occurring during adulthood (second hit) in rodents. We then provide a comprehensive overview of the potential mechanisms underlying interindividual and sex differences in the resilience/susceptibility to developing stress-related disorders later in life when stress is experienced in two different life stages.
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Affiliation(s)
- Giulia F Mancini
- Dept. of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy; Department of Medicine, Division of Endocrinology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Onno C Meijer
- Department of Medicine, Division of Endocrinology, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Patrizia Campolongo
- Dept. of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy; Neuropsychopharmacology Unit, IRCSS Fondazione Santa Lucia, 00143 Rome, Italy.
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Shan Q, Yu X, Tian Y. Adolescent social isolation shifts the balance of decision-making strategy from goal-directed action to habitual response in adulthood via suppressing the excitatory neurotransmission onto the direct pathway of the dorsomedial striatum. Cereb Cortex 2023; 33:1595-1609. [PMID: 35524719 DOI: 10.1093/cercor/bhac158] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/15/2022] [Accepted: 04/01/2022] [Indexed: 02/05/2023] Open
Abstract
Adverse experience, such as social isolation, during adolescence is one of the major causes of neuropsychiatric disorders that extend from adolescence into adulthood, such as substance addiction, obsessive-compulsive disorder, and eating disorders leading to obesity. A common behavioral feature of these neuropsychiatric disorders is a shift in the balance of decision-making strategy from goal-directed action to habitual response. This study has verified that adolescent social isolation directly shifts the balance of decision-making strategy from goal-directed action to habitual response, and that it cannot be reversed by simple regrouping. This study has further revealed that adolescent social isolation induces a suppression in the excitatory neurotransmission onto the direct-pathway medium spiny neurons of the dorsomedial striatum (DMS), and that chemogenetically compensating this suppression effect shifts the balance of decision-making strategy from habitual response back to goal-directed action. These findings suggest that the plasticity in the DMS causes the shift in the balance of decision-making strategy, which would potentially help to develop a general therapy to treat the various neuropsychiatric disorders caused by adolescent social isolation. Such a study is especially necessary under the circumstances that social distancing and lockdown have caused during times of world-wide, society-wide pandemic.
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Affiliation(s)
- Qiang Shan
- Laboratory for Synaptic Plasticity, Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Xiaoxuan Yu
- Laboratory for Synaptic Plasticity, Shantou University Medical College, Shantou, Guangdong, 515041, China
| | - Yao Tian
- Chern Institute of Mathematics, Nankai University, Tianjin, 300071, China
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Broadfoot CK, Lenell C, Kelm-Nelson CA, Ciucci MR. Effects of social isolation on 50-kHz ultrasonic vocalizations, affective state, cognition, and neurotransmitter concentrations in the ventral tegmental and locus coeruleus of adult rats. Behav Brain Res 2023; 437:114157. [PMID: 36241070 PMCID: PMC9829432 DOI: 10.1016/j.bbr.2022.114157] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/23/2022] [Accepted: 10/09/2022] [Indexed: 11/05/2022]
Abstract
Vocal communication, cognition, and affective state are key features of sustained health and wellness, and because vocalizations are often socially-motivated, social experience likely plays a role in these behaviors. The monoaminergic systems of the ventral tegmental area (VTA) and the locus coeruleus (LC) are associated with social and reward processing, vocalization production, and neurotransmitter changes in response to environmental stressors. The effect of social isolation on these complex behaviors and the underlying neural mechanisms is relatively unknown. To add to this body of literature, we randomized adult male Long-Evans rats to control (housed with a cagemate) or isolated (housed individually) conditions and assayed ultrasonic vocalizations, cognition (novel object recognition test), anxiety (elevated plus maze) and anhedonia (sucrose preference test) at 2, 4, 6, 8, and 10 months of age. At 10 months, VTA and LC samples were assayed for dopamine, norepinephrine, and serotonin using high performance liquid chromatography. We tested the hypotheses that isolation 1) diminishes vocalizations and cognition, 2) increases anxiety and depression, and 3) increases levels of dopamine, norepinephrine, and serotonin in the VTA and LC. Results showed isolation significantly reduced vocalization tonality (signal-to-noise ratio) and increased maximum frequency. There were no significant findings for cognition, anxiety, or anhedonia. Dopamine and serotonin and their respective metabolites were significantly increased in the VTA in isolated rats. These findings suggest chronic changes to social condition such as isolation affects vocalization production and levels of VTA neurotransmitters.
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Affiliation(s)
- Courtney K Broadfoot
- Department of Communication Sciences and Disorders, University of Wisconsin-Madison, 1975 Willow Drive, Madison, WI 53706, USA; Department of Surgery, Division of Otolaryngology-Head & Neck Surgery, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792, USA.
| | - Charles Lenell
- Department of Audiology and Speech-Language Sciences, University of Northern Colorado, 1400 Gunter Hall, Greenly, CO 80639, USA
| | - Cynthia A Kelm-Nelson
- Department of Surgery, Division of Otolaryngology-Head & Neck Surgery, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792, USA
| | - Michelle R Ciucci
- Department of Communication Sciences and Disorders, University of Wisconsin-Madison, 1975 Willow Drive, Madison, WI 53706, USA; Department of Surgery, Division of Otolaryngology-Head & Neck Surgery, University of Wisconsin-Madison, 600 Highland Avenue, Madison, WI 53792, USA; Neuroscience Training Program, University of Wisconsin-Madison, 9531 MIMR II, 1111 Highland Avenue, Madison, WI 53705, USA
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11
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Guo H, Näslund J, Thomassen ST, Larsen MH. Social isolation affects intra-specific interaction behaviour and reduces the size of the cerebellar brain region in juvenile Atlantic salmon Salmo salar. JOURNAL OF FISH BIOLOGY 2022; 101:711-721. [PMID: 35751413 PMCID: PMC9540882 DOI: 10.1111/jfb.15142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
The social environment can affect the development of behavioural phenotypes in fish, and it is important to understand such effects when rearing fish in artificial environments. Here, the authors test the effects of spatial isolation on social interaction propensity and brain development in hatchery-reared Atlantic salmon Salmo salar L. Salmon reared in isolation generally stayed further away from a conspecific in a standardized intruder test than conspecifics reared together in groups. Isolated salmon also tended to be more active in an intruder test, albeit non-significantly so, but this pattern was not detected in open-field tests without an intruding conspecific. The cerebellar brain region was relatively smaller in isolated salmon, suggesting that the brain was developing differently in these fish. Therefore, some features of the behavioural and neural phenotype are affected by rearing in isolation. These effects should be considered when rearing salmon, particularly for experimental purposes as it may affect results of laboratory studies on behavioural expression and brain size.
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Affiliation(s)
- Haoyu Guo
- Fisheries CollegeZhejiang Ocean UniversityZhoushanChina
| | - Joacim Näslund
- Department of Aquatic ResourcesInstitute of Freshwater Research, Swedish University of Agricultural SciencesDrottningholmSweden
| | | | - Martin H. Larsen
- Danish Centre for Wild SalmonRandersDenmark
- National Institute of Aquatic ResourcesSection for Freshwater Fisheries Ecology, Technical University of DenmarkSilkeborgDenmark
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12
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Investigating the Role of GABA in Neural Development and Disease Using Mice Lacking GAD67 or VGAT Genes. Int J Mol Sci 2022; 23:ijms23147965. [PMID: 35887307 PMCID: PMC9318753 DOI: 10.3390/ijms23147965] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 07/12/2022] [Accepted: 07/16/2022] [Indexed: 11/18/2022] Open
Abstract
Normal development and function of the central nervous system involves a balance between excitatory and inhibitory neurotransmission. Activity of both excitatory and inhibitory neurons is modulated by inhibitory signalling of the GABAergic and glycinergic systems. Mechanisms that regulate formation, maturation, refinement, and maintenance of inhibitory synapses are established in early life. Deviations from ideal excitatory and inhibitory balance, such as down-regulated inhibition, are linked with many neurological diseases, including epilepsy, schizophrenia, anxiety, and autism spectrum disorders. In the mammalian forebrain, GABA is the primary inhibitory neurotransmitter, binding to GABA receptors, opening chloride channels and hyperpolarizing the cell. We review the involvement of down-regulated inhibitory signalling in neurological disorders, possible mechanisms for disease progression, and targets for therapeutic intervention. We conclude that transgenic models of disrupted inhibitory signalling—in GAD67+/− and VGAT−/− mice—are useful for investigating the effects of down-regulated inhibitory signalling in a range of neurological diseases.
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13
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Wang ZY, McKenzie-Smith GC, Liu W, Cho HJ, Pereira T, Dhanerawala Z, Shaevitz JW, Kocher SD. Isolation disrupts social interactions and destabilizes brain development in bumblebees. Curr Biol 2022; 32:2754-2764.e5. [PMID: 35584698 PMCID: PMC9233014 DOI: 10.1016/j.cub.2022.04.066] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/28/2022] [Accepted: 04/22/2022] [Indexed: 12/24/2022]
Abstract
Social isolation, particularly in early life, leads to deleterious physiological and behavioral outcomes. Here, we leverage new high-throughput tools to comprehensively investigate the impact of isolation in the bumblebee, Bombus impatiens, from behavioral, molecular, and neuroanatomical perspectives. We reared newly emerged bumblebees in complete isolation, in small groups, or in their natal colony, and then analyzed their behaviors while alone or paired with another bee. We find that when alone, individuals of each rearing condition show distinct behavioral signatures. When paired with a conspecific, bees reared in small groups or in the natal colony express similar behavioral profiles. Isolated bees, however, showed increased social interactions. To identify the neurobiological correlates of these differences, we quantified brain gene expression and measured the volumes of key brain regions for a subset of individuals from each rearing condition. Overall, we find that isolation increases social interactions and disrupts gene expression and brain development. Limited social experience in small groups is sufficient to preserve typical patterns of brain development and social behavior.
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Affiliation(s)
- Z Yan Wang
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA; Lewis Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA
| | - Grace C McKenzie-Smith
- Lewis Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA; Department of Physics, Princeton University, Princeton, NJ, USA
| | - Weijie Liu
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - Hyo Jin Cho
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - Talmo Pereira
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
| | - Zahra Dhanerawala
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA; Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Joshua W Shaevitz
- Lewis Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA; Department of Physics, Princeton University, Princeton, NJ, USA
| | - Sarah D Kocher
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA; Lewis Sigler Institute of Integrative Genomics, Princeton University, Princeton, NJ, USA.
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14
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Bove M, Lama A, Schiavone S, Pirozzi C, Tucci P, Sikora V, Trinchese G, Corso G, Morgese MG, Trabace L. Social isolation triggers oxidative status and impairs systemic and hepatic insulin sensitivity in normoglycemic rats. Biomed Pharmacother 2022; 149:112820. [PMID: 35290886 DOI: 10.1016/j.biopha.2022.112820] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 02/28/2022] [Accepted: 03/09/2022] [Indexed: 11/11/2022] Open
Abstract
Drug-naïve psychotic patients show metabolic and hepatic dysfunctions. The rat social isolation model of psychosis allows to investigate mechanisms leading to these disturbances to which oxidative stress crucially contributes. Here, we investigated isolation-induced central and peripheral dysfunctions in glucose homeostasis and insulin sensitivity, along with redox dysregulation. Social isolation did not affect basal glycemic levels and the response to glucose and insulin loads in the glucose and insulin tolerance tests. However, HOMA-Index value were increased in isolated (ISO) rats. A hypothalamic reduction of AKT phosphorylation and a trend toward an increase in AMPK phosphorylation were observed following social isolation, accompanied by reduced GLUT-4 levels. Social isolation also induced a reduction of phosphorylation of the insulin receptor, of AKT and GLUT-2, and a decreased phosphorylation of AMPK in the liver. Furthermore, a significant reduction in hepatic CPT1 and PPAR-α levels was detected. ISO rats also showed significant elevations in hepatic ROS amount, lipid peroxidation and NOX4 expression, whereas no differences were detected in NOX2 and NOX1 levels. Expression of SOD2 in the mitochondrial fraction and SOD1 in the cytosolic fraction was not altered following social isolation, whereas SOD activity was increased. Furthermore, a decrease of hepatic CAT and GSH amount was observed in ISO rats compared to GRP animals. Our data suggest that the increased oxidant status and antioxidant capacity modifications may trigger hepatic and systemic insulin resistance, by altering signal hormone pathway and sustaining subsequent alteration of glucose homeostasis and metabolic impairment observed in the social isolation model of psychosis.
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Affiliation(s)
- Maria Bove
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy.
| | - Adriano Lama
- Department of Pharmacy, University of Naples Federico II, Via Domenico Montesano, 49, Naples 80131, Italy.
| | - Stefania Schiavone
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy.
| | - Claudio Pirozzi
- Department of Pharmacy, University of Naples Federico II, Via Domenico Montesano, 49, Naples 80131, Italy.
| | - Paolo Tucci
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy.
| | - Vladyslav Sikora
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy; Department of Pathology, Sumy State University, 2, Rymskogo-Korsakova st., Sumy 40007, Ukraine.
| | - Giovanna Trinchese
- Department of Biology, University of Naples Federico II, "Complesso Universitario di Monte Sant'Angelo", Cupa Nuova Cinthia 21 - Building 7, Naples 80126, Italy.
| | - Gaetano Corso
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy.
| | - Maria Grazia Morgese
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy.
| | - Luigia Trabace
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli, 20, Foggia 71122, Italy.
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15
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Vitale EM, Smith AS. Neurobiology of Loneliness, Isolation, and Loss: Integrating Human and Animal Perspectives. Front Behav Neurosci 2022; 16:846315. [PMID: 35464141 PMCID: PMC9029604 DOI: 10.3389/fnbeh.2022.846315] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 02/21/2022] [Indexed: 12/30/2022] Open
Abstract
In social species such as humans, non-human primates, and even many rodent species, social interaction and the maintenance of social bonds are necessary for mental and physical health and wellbeing. In humans, perceived isolation, or loneliness, is not only characterized by physical isolation from peers or loved ones, but also involves negative perceptions about social interactions and connectedness that reinforce the feelings of isolation and anxiety. As a complex behavioral state, it is no surprise that loneliness and isolation are associated with dysfunction within the ventral striatum and the limbic system - brain regions that regulate motivation and stress responsiveness, respectively. Accompanying these neural changes are physiological symptoms such as increased plasma and urinary cortisol levels and an increase in stress responsivity. Although studies using animal models are not perfectly analogous to the uniquely human state of loneliness, studies on the effects of social isolation in animals have observed similar physiological symptoms such as increased corticosterone, the rodent analog to human cortisol, and also display altered motivation, increased stress responsiveness, and dysregulation of the mesocortical dopamine and limbic systems. This review will discuss behavioral and neuropsychological components of loneliness in humans, social isolation in rodent models, and the neurochemical regulators of these behavioral phenotypes with a neuroanatomical focus on the corticostriatal and limbic systems. We will also discuss social loss as a unique form of social isolation, and the consequences of bond disruption on stress-related behavior and neurophysiology.
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Affiliation(s)
- Erika M. Vitale
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, United States
| | - Adam S. Smith
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Kansas, Lawrence, KS, United States
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16
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Rubio Arzola P, Shansky RM. Considering Organismal Physiology in Laboratory Studies of Rodent Behavior. Annu Rev Neurosci 2022; 45:387-402. [PMID: 35395164 DOI: 10.1146/annurev-neuro-111020-085500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Any experiment conducted in a rodent laboratory is done so against the backdrop of each animal's physiological state at the time of the experiment. This physiological state can be the product of multiple factors, both internal (e.g., animal sex, strain, hormone cycles, or circadian rhythms) and external (e.g., housing conditions, social status, and light/dark phases). Each of these factors has the potential to influence experimental outcomes, either independently or via interactions with others, and yet there is little consistency across laboratories in terms of the weight with which they are considered in experimental design. Such discrepancies-both in practice and in reporting-likely contribute to the perception of a reproducibility crisis in the field of behavioral neuroscience. In this review, we discuss how several of these sources of variability can impact outcomes within the realm of common learning and memory paradigms. Expected final online publication date for the Annual Review of Neuroscience, Volume 45 is July 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
| | - Rebecca M Shansky
- Department of Psychology, Northeastern University, Boston, Massachusetts, USA;
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17
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D'avila LF, Dias VT, Trevizol F, Metz VG, Roversi K, Milanesi L, Maurer LH, Baranzelli J, Emanuelli T, Burger ME. INTERESTERIFIED FAT MATERNAL CONSUMPTION BEFORE CONCEPTION PROGRAMMS MEMORY AND LEARNING OF ADULTHOOD OFFSPRING: how big is this deleterious repercussion? Toxicol Lett 2022; 361:10-20. [PMID: 35301046 DOI: 10.1016/j.toxlet.2022.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 11/25/2022]
Abstract
In recent years, interesterified fat (IF) has largely replaced trans fat in industrialized food. Studies of our research group showed that IF consumption may not be safe for central nervous system (CNS) functions. Our current aim was to evaluate IF maternal consumption before conception on cognitive performance of adult rat offspring. Female Wistar rats were fed with standard chow plus 20% soybean and fish oil mix (control group) or plus 20% IF from weaning until adulthood (before mating), when the diets were replaced by standard chow only. Following the gestation and pups' development, locomotion and memory performance followed by neurotrophin immunocontent and fatty acids (FA) profile in the hippocampus of the adulthood male offspring were quantified. Maternal IF consumption before conception decreased hippocampal palmitoleic acid incorporation, proBDNF and BDNF levels, decreasing both exploratory activity and memory performance in adult offspring. Considering that, the adult male offspring did not consume IF directly, further studies are needed to understand the molecular mechanisms and if the IF maternal preconception consumption could induce the epigenetic changes observed here. Our outcomes reinforce an immediate necessity to monitor and / or question the replacement of trans fat by IF with further studies involving CNS functions.
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Affiliation(s)
- Lívia Ferraz D'avila
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Verônica Tironi Dias
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Fabíola Trevizol
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Vinícia Garzella Metz
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Karine Roversi
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Laura Milanesi
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Luana Haselein Maurer
- Programa de Pós-graduação em Ciência e Tecnologia dos Alimentos, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Júlia Baranzelli
- Programa de Pós-graduação em Ciência e Tecnologia dos Alimentos, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Tatiana Emanuelli
- Programa de Pós-graduação em Ciência e Tecnologia dos Alimentos, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
| | - Marilise Escobar Burger
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil; Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria (UFSM), RS, Brazil.
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18
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Krimberg JS, Lumertz FS, Orso R, Viola TW, de Almeida RMM. Impact of social isolation on the oxytocinergic system: A systematic review and meta-analysis of rodent data. Neurosci Biobehav Rev 2022; 134:104549. [PMID: 35074312 DOI: 10.1016/j.neubiorev.2022.104549] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/29/2021] [Accepted: 01/20/2022] [Indexed: 01/31/2023]
Abstract
Social isolation (SI) stress results from a combination of intrinsic and environmental factors and is associated with a variety of negative developmental outcomes. Oxytocin (OXT) might play a role in the consequences of SI in the brain and periphery. We conducted a systematic review and meta-analysis to compile data about the effects of SI in the oxytocinergic system of rats and mice, and its relation to behavioral alterations. Five databases (EMBASE, PsychNet, PubMed, Scopus, and Web of Science) in March 2021, using ("Social Isolation" AND (mouse OR rat) AND (oxytocin OR oxytocin receptor)). This review followed the PRISMA guidelines, including registration in PROSPERO, and risk of bias assessment. The twelve articles included in this review indicated that SI was associated with decreased OXTR levels, resulting in behavioral alterations like increased aggression and anxiety-like behavior, hyperactivity, and diminished social behaviors and memory. No significant effects on OXT levels were observed. Administration of synthetic OXT or its agonists partially decreases those unwanted behaviors to similar levels of control animals.
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Affiliation(s)
- Júlia S Krimberg
- Neuroscience Graduate Program, Basic Health Sciences Institute (IBCS), Universidade Federal of Rio Grande do Sul (UFRGS), Rua Sarmento Leite, 500, Centro Histórico, Porto Alegre, RS, 90050-170, Brazil; Experimental Psychology, Neuroscience and Behavior Laboratory (LPNeC), Psychology Institute, Universidade Federal of Rio Grande do Sul (UFRGS), Rua Ramiro Barcellos, 2600, Room 216. Santa Cecília, Porto Alegre, RS, 90035-003, Brazil.
| | - Francisco S Lumertz
- Developmental Cognitive Neuroscience Lab (DCNL), Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690, Building 63, Jardim Botânico, Porto Alegre, RS, 90619-900, Brazil.
| | - Rodrigo Orso
- Developmental Cognitive Neuroscience Lab (DCNL), Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690, Building 63, Jardim Botânico, Porto Alegre, RS, 90619-900, Brazil.
| | - Thiago W Viola
- Developmental Cognitive Neuroscience Lab (DCNL), Brain Institute of Rio Grande do Sul, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Av. Ipiranga, 6690, Building 63, Jardim Botânico, Porto Alegre, RS, 90619-900, Brazil.
| | - Rosa Maria M de Almeida
- Neuroscience Graduate Program, Basic Health Sciences Institute (IBCS), Universidade Federal of Rio Grande do Sul (UFRGS), Rua Sarmento Leite, 500, Centro Histórico, Porto Alegre, RS, 90050-170, Brazil; Experimental Psychology, Neuroscience and Behavior Laboratory (LPNeC), Psychology Institute, Universidade Federal of Rio Grande do Sul (UFRGS), Rua Ramiro Barcellos, 2600, Room 216. Santa Cecília, Porto Alegre, RS, 90035-003, Brazil.
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19
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Estave PM, Spodnick MB, Karkhanis AN. KOR Control over Addiction Processing: An Exploration of the Mesolimbic Dopamine Pathway. Handb Exp Pharmacol 2022; 271:351-377. [PMID: 33301050 PMCID: PMC8192597 DOI: 10.1007/164_2020_421] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Drug addiction is a complex, persistent, and chronically relapsing neurological disorder exacerbated by acute and chronic stress. It is well known that the dynorphin/kappa opioid receptor (KOR) system regulates stress perception and responsivity, while the mesolimbic dopamine system plays a role in reward and reinforcement associated with alcohol and substance use disorders. Interestingly, the dopamine and dynorphin/KOR systems are highly integrated in mesolimbic areas, with KOR activation leading to inhibition of dopamine release, further altering the perception of reinforcing and aversive stimuli. Chronic or repeated exposure to stress or drugs potentiates KOR function ultimately contributing to a hypodopaminergic state. This hypodopaminergic state is one of the hallmarks of hyperkatifeia, defined as the hypersensitivity to emotional distress that is exacerbated during drug withdrawal and abstinence. The relationship between stress and drug addiction is bidirectional; repeated/chronic stress promotes pro-addictive behaviors, and repeated cycles of drug exposure and withdrawal, across various drug classes, produces stress. Neuroadaptations driven by this bidirectional relationship ultimately influence the perception of the reinforcing value of rewarding stimuli. In this chapter, we address the involvement of the dopamine and dynorphin/KOR systems and their interactions in shaping reinforcement value processing after drug and stress exposure, as well as a combinatorial impact of both drugs and stress.
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Affiliation(s)
- Paige M Estave
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Mary B Spodnick
- Department of Psychology, Developmental Exposure Alcohol Research Center, Center for Developmental and Behavioral Neuroscience, Binghamton University - SUNY, Binghamton, NY, USA
| | - Anushree N Karkhanis
- Department of Psychology, Developmental Exposure Alcohol Research Center, Center for Developmental and Behavioral Neuroscience, Binghamton University - SUNY, Binghamton, NY, USA.
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20
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Myslivecek J. Social Isolation: How Can the Effects on the Cholinergic System Be Isolated? Front Pharmacol 2021; 12:716460. [PMID: 34916930 PMCID: PMC8670609 DOI: 10.3389/fphar.2021.716460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 11/15/2021] [Indexed: 01/31/2023] Open
Abstract
Social species form organizations that support individuals because the consequent social behaviors help these organisms survive. The isolation of these individuals may be a stressor. We reviewed the potential mechanisms of the effects of social isolation on cholinergic signaling and vice versa how changes in cholinergic signaling affect changes due to social isolation.There are two important problems regarding this topic. First, isolation schemes differ in their duration (1–165 days) and initiation (immediately after birth to adulthood). Second, there is an important problem that is generally not considered when studying the role of the cholinergic system in neurobehavioral correlates: muscarinic and nicotinic receptor subtypes do not differ sufficiently in their affinity for orthosteric site agonists and antagonists. Some potential cholinesterase inhibitors also affect other targets, such as receptors or other neurotransmitter systems. Therefore, the role of the cholinergic system in social isolation should be carefully considered, and multiple receptor systems may be involved in the central nervous system response, although some subtypes are involved in specific functions. To determine the role of a specific receptor subtype, the presence of a specific subtype in the central nervous system should be determined using search in knockout studies with the careful application of specific agonists/antagonists.
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Affiliation(s)
- Jaromir Myslivecek
- Institute of Physiology, First Faculty of Medicine, Charles University, Prague, Czechia
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21
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Perić I, Costina V, Djordjević S, Gass P, Findeisen P, Inta D, Borgwardt S, Filipović D. Tianeptine modulates synaptic vesicle dynamics and favors synaptic mitochondria processes in socially isolated rats. Sci Rep 2021; 11:17747. [PMID: 34493757 PMCID: PMC8423821 DOI: 10.1038/s41598-021-97186-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 08/09/2021] [Indexed: 11/09/2022] Open
Abstract
Deregulation of synaptic function and neurotransmission has been linked with the development of major depression disorder (MDD). Tianeptine (Tian) has been used as antidepressant with anxiolytic properties and recently as a nootropic to improve cognitive performance, but its mechanism of action is unknown. We conducted a proteomic study on the hippocampal synaptosomal fractions of adult male Wistar rats exposed to chronic social isolation (CSIS, 6 weeks), an animal model of depression and after chronic Tian treatment in controls (nootropic effect) and CSIS-exposed rats (lasting 3 weeks of 6-week CSIS) (therapeutic effect). Increased expression of Syn1 and Camk2-related neurotransmission, vesicle transport and energy processes in Tian-treated controls were found. CSIS led to upregulation of proteins associated with actin cytoskeleton, signaling transduction and glucose metabolism. In CSIS rats, Tian up-regulated proteins involved in mitochondrial energy production, mitochondrial transport and dynamics, antioxidative defense and glutamate clearance, while attenuating the CSIS-increased glycolytic pathway and cytoskeleton organization proteins expression and decreased the expression of proteins involved in V-ATPase and vesicle endocytosis. Our overall findings revealed that synaptic vesicle dynamics, specifically exocytosis, and mitochondria-related energy processes might be key biological pathways modulated by the effective nootropic and antidepressant treatment with Tian and be a potential target for therapeutic efficacy of the stress-related mood disorders.
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Affiliation(s)
- Ivana Perić
- Department of Molecular Biology and Endocrinology, "VINČA", Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Victor Costina
- Institute for Clinical Chemistry, Medical Faculty Mannheim of the University of Heidelberg, University Hospital Mannheim, 68159, Mannheim, Germany
| | | | - Peter Gass
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, 68159, Mannheim, Germany
| | - Peter Findeisen
- Institute for Clinical Chemistry, Medical Faculty Mannheim of the University of Heidelberg, University Hospital Mannheim, 68159, Mannheim, Germany
| | - Dragoš Inta
- Department of Psychiatry (UPK), University of Basel, Basel, Switzerland
| | - Stefan Borgwardt
- Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, Germany
| | - Dragana Filipović
- Department of Molecular Biology and Endocrinology, "VINČA", Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia.
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22
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Varga TG, de Toledo Simões JG, Siena A, Henrique E, da Silva RCB, Dos Santos Bioni V, Ramos AC, Rosenstock TR. Haloperidol rescues the schizophrenia-like phenotype in adulthood after rotenone administration in neonatal rats. Psychopharmacology (Berl) 2021; 238:2569-2585. [PMID: 34089344 DOI: 10.1007/s00213-021-05880-1] [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] [Received: 09/22/2020] [Accepted: 05/20/2021] [Indexed: 10/21/2022]
Abstract
Neuropsychiatric disorders are multifactorial disturbances that encompass several hypotheses, including changes in neurodevelopment. It is known that brain development disturbances during early life can predict psychosis in adulthood. As we have previously demonstrated, rotenone, a mitochondrial complex I inhibitor, could induce psychiatric-like behavior in 60-day-old rats after intraperitoneal injections from the 5th to the 11th postnatal day. Because mitochondrial deregulation is related to psychiatric disorders and the establishment of animal models is a high-value preclinical tool, we investigated the responsiveness of the rotenone (Rot)-treated newborn rats to pharmacological agents used in clinical practice, haloperidol (Hal), and methylphenidate (MPD). Taken together, our data show that Rot-treated animals exhibit hyperlocomotion, decreased social interaction, and diminished contextual fear conditioning response at P60, consistent with positive, negative, and cognitive deficits of schizophrenia (SZ), respectively, that were reverted by Hal, but not MPD. Rot-treated rodents also display a prodromal-related phenotype at P35. Overall, our results seem to present a new SZ animal model as a consequence of mitochondrial inhibition during a critical neurodevelopmental period. Therefore, our study is crucial not only to elucidate the relevance of mitochondrial function in the etiology of SZ but also to fulfill the need for new and trustworthy experimentation models and, likewise, provide possibilities to new therapeutic avenues for this burdensome disorder.
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Affiliation(s)
- Thiago Garcia Varga
- Department of Physiological Science, Santa Casa de São Paulo School of Medical Science, São Paulo, Brazil
| | | | - Amanda Siena
- Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, Av. Prof. Lineu Prestes, 1524 - Ed. Biomédicas I, 2º andar, São Paulo, SP, 05508-900, Brazil
| | - Elisandra Henrique
- Department of Physiological Science, Santa Casa de São Paulo School of Medical Science, São Paulo, Brazil
| | | | | | - Aline Camargo Ramos
- Department of Psychiatry, Federal University of São Paulo, São Paulo, Brazil
| | - Tatiana Rosado Rosenstock
- Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, Av. Prof. Lineu Prestes, 1524 - Ed. Biomédicas I, 2º andar, São Paulo, SP, 05508-900, Brazil. .,Institute of Cancer and Genomic Sciences, Institute of Biomedical Research, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
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23
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Peña-Vargas C, Armaiz-Peña G, Castro-Figueroa E. A Biopsychosocial Approach to Grief, Depression, and the Role of Emotional Regulation. Behav Sci (Basel) 2021; 11:110. [PMID: 34436100 PMCID: PMC8389251 DOI: 10.3390/bs11080110] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 12/27/2022] Open
Abstract
According to the field of affective neuroscience, grief has been identified as one of the seven primary emotions necessary for human survival. However, maladaptive grief could cause significant impairment in an individual's life, leading to psychopathologies such as major depressive disorder. Research on grief has shifted to a biopsychosocial approach, leaving behind outdated models-such as the Kübler-Ross theory-that have shown poor consistency. The field of psychoneuroimmunology has identified adverse life events such as social loss as being associated with major depressive disorder, and inflammatory processes in chronic health conditions. Likewise, scientists in the field of affective neuroscience have theorized that prolonged and sustained activation of the grief neurological pathway can cause a cascade of neurotransmitters that inhibits the reward-seeking system, causing symptoms of depression. The objective of this review is to highlight findings on the grief process using a biopsychosocial approach to explore grief's impact on psychopathophysiology.
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Affiliation(s)
- Cristina Peña-Vargas
- Ponce’s Research Institute, Ponce Health Sciences University, Ponce, PR 00716, USA
| | | | - Eida Castro-Figueroa
- School of behavioral and Brain Sciences, Ponce Health Sciences University, Ponce, PR 00716, USA;
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24
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Novoa J, Rivero CJ, Pérez-Cardona EU, Freire-Arvelo JA, Zegers J, Yarur HE, Santiago-Marerro IG, Agosto-Rivera JL, González-Pérez JL, Gysling K, Segarra AC. Social isolation of adolescent male rats increases anxiety and K + -induced dopamine release in the nucleus accumbens: Role of CRF-R1. Eur J Neurosci 2021; 54:4888-4905. [PMID: 34097788 DOI: 10.1111/ejn.15345] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 04/08/2021] [Accepted: 05/04/2021] [Indexed: 12/19/2022]
Abstract
Early life adversity can disrupt development leading to emotional and cognitive disorders. This study investigated the effects of social isolation after weaning on anxiety, body weight and locomotion, and on extracellular dopamine (DA) and glutamate (GLU) in the nucleus accumbens (NAc) and their modulation by corticotropin releasing factor receptor 1. On the day of weaning, male rats were housed singly or in groups for 10 consecutive days. Anxiety-like behaviors were assessed by an elevated plus maze (EPM) and an open field test (OF). Neurotransmitter levels were measured by in vivo microdialysis. Single-housed rats spent less time, and entered more, into the closed arms of an EPM than group-housed rats. They also spent less time in the center of an OF, weighed more and showed greater locomotion. In the NAc, no differences in CRF, or in basal extracellular DA or GLU between groups, were observed. A depolarizing stimulus increased DA release in both groups but to higher levels in isolated rats, whereas GLU increased only in single-housed rats. Blocking CRF-R1 receptors with CP-154,526 decreased DA release in single-housed but not in group-housed rats. The corticotropin releasing factor receptor type 1 receptor antagonist also decreased GLU in group-housed animals. These results show that isolating adolescent rats increases anxiety, body weight and ambulation, as well as the sensitivity of dopaminergic neurons to a depolarizing stimulus. This study provides further evidence of the detrimental effects of social isolation during early development and indicates that dysregulation of the CRF system in the NAc may contribute to the pathologies observed.
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Affiliation(s)
- Javier Novoa
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos J Rivero
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
| | - Enrique U Pérez-Cardona
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
| | - Jaime A Freire-Arvelo
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
| | - Juan Zegers
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Héctor E Yarur
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | | | - Jorge L González-Pérez
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
| | - Katia Gysling
- Department of Cellular and Molecular Biology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Annabell C Segarra
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
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25
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Post-weaning social isolation impairs purinergic signaling in rat brain. Neurochem Int 2021; 148:105111. [PMID: 34171414 DOI: 10.1016/j.neuint.2021.105111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/25/2021] [Accepted: 06/20/2021] [Indexed: 01/14/2023]
Abstract
Early life stressors, such as social isolation (SI), can disrupt brain development contributing to behavioral and neurochemical alterations in adulthood. Purinergic receptors and ectonucleotidases are key regulators of brain development in embryonic and postnatal periods, and they are involved in several psychiatric disorders, including schizophrenia. The extracellular ATP drives purinergic signaling by activating P2X and P2Y receptors and it is hydrolyzed by ectonucleotidases in adenosine, which activates P1 receptors. The purpose of this study was to investigate if SI, a rodent model used to replicate abnormal behavior relevant to schizophrenia, impacts purinergic signaling. Male Wistar rats were reared from weaning in group-housed or SI conditions for 8 weeks. SI rats exhibited impairment in prepulse inhibition and social interaction. SI presented increased ADP levels in cerebrospinal fluid and ADP hydrolysis in the hippocampus and striatum synaptosomes. Purinergic receptor expressions were upregulated in the prefrontal cortex and downregulated in the hippocampus and striatum. A2A receptors were differentially expressed in SI prefrontal cortex and the striatum, suggesting distinct roles in these brain structures. SI also presented decreased ADP, adenosine, and guanosine levels in the cerebrospinal fluid in response to D-amphetamine. Like patients with schizophrenia, uric acid levels were prominently increased in SI rats after D-amphetamine challenge. We suggest that the SI-induced deficits in prepulse inhibition might be related to the SI-induced changes in purinergic signaling. We provide new evidence that purinergic signaling is markedly affected in a rat model relevant to schizophrenia, pointing out the importance of purinergic system in psychiatry conditions.
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Gondora N, Pople CB, Tandon G, Robinson M, Solomon E, Beazely MA, Mielke JG. Chronic early-life social isolation affects NMDA and TrkB receptor expression in a sex-specific manner. Neurosci Lett 2021; 760:136016. [PMID: 34111511 DOI: 10.1016/j.neulet.2021.136016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 05/22/2021] [Accepted: 06/06/2021] [Indexed: 12/27/2022]
Abstract
Exposing mammals to adverse social environments early in life can affect brain development in ways that alter adult behaviour. For example, chronic, early-life social isolation (CELSI) has been found to cause novelty-induced hyperactivity, impaired pre-pulse inhibition, and enhanced anxiety-related behaviour. Although the molecular mechanism(s) underlying the embedding of CELSI have not been fully elucidated, evidence suggests changes in the level of excitatory neurotransmission and neurotrophic factor signalling may be quite important. Since much of the work in this area has focused upon mRNA-level analyses, and has shown variable responses across both brain region and animal sex, our study aimed to explore the impact of CELSI on the expression of two important plasticity-related proteins (Tropomyosin receptor kinase B and the GluN2B subunit of the NMDA receptor) in the pre-frontal cortex and hippocampus of both male and female rats. We observed that the expression of both proteins was clearly changed by CELSI, but that the effect occurred in a sex (but not region) specific manner. Our results support the growing view that early-life adversity can cause structural changes reasonably associated with adult behaviour, and emphasise that the study of such changes benefits from a sex-based analysis.
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Affiliation(s)
- Nyasha Gondora
- School of Pharmacy, University of Waterloo, 10 Victoria Street S, Kitchener, Ontario N2G 1C5, Canada
| | - Christopher B Pople
- Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, Ontario M4N 3M5, Canada
| | - Gorvie Tandon
- School of Nursing, York University, 400 Keele Toronto, Ontario M3J 1P3, Canada
| | - Morgan Robinson
- School of Pharmacy, University of Waterloo, 10 Victoria Street S, Kitchener, Ontario N2G 1C5, Canada
| | - Eden Solomon
- Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Michael A Beazely
- School of Pharmacy, University of Waterloo, 10 Victoria Street S, Kitchener, Ontario N2G 1C5, Canada
| | - John G Mielke
- School of Public Health Sciences, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.
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27
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Wang P, Li M, Zhao A, Ma J. Application of animal experimental models in the research of schizophrenia. Am J Med Genet B Neuropsychiatr Genet 2021; 186:209-227. [PMID: 34155806 DOI: 10.1002/ajmg.b.32863] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 05/04/2021] [Accepted: 05/31/2021] [Indexed: 12/14/2022]
Abstract
Schizophrenia is a relatively common but serious mental illness that results in a heavy burden to patients, their families, and society. The disease can be triggered by multiple factors, while the specific pathogenesis remains unclear. The development of effective therapeutic drugs for schizophrenia relies on a comprehensive understanding of the basic biology and pathophysiology of the disease. Therefore, effective animal experimental models play a vital role in the study of schizophrenia. Based on different molecular mechanisms and modeling methods, the currently used experimental animal experimental models of schizophrenia can be divided into four categories that can better simulate the clinical symptoms and the interplay between susceptible genes and the environment: neurodevelopmental, drug-induced, genetic-engineering, and genetic-environmental interaction of animal experimental models. Each of these categories contains multiple subtypes, which has its own advantages and disadvantages and therefore requires careful selection in a research application. The emergence and utilization of these models are promising in the prediction of the risk of schizophrenia at the molecular level, which will shed light on effective and targeted treatment at the genetic level.
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Affiliation(s)
- Pengjie Wang
- Medical Research Center, Xi'an No.3 Hospital, the Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China.,Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Manling Li
- School of Basic Medicine, Guizhou University of Traditional Chinese Medicine, Gui Yang, Guizhou, China
| | - Aizhen Zhao
- Medical Research Center, Xi'an No.3 Hospital, the Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China
| | - Jie Ma
- Medical Research Center, Xi'an No.3 Hospital, the Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China.,Department of Electron Microscope, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
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28
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Davis SED, Sansone JM, Hurley LM. Postweaning Isolation Alters the Responses of Auditory Neurons to Serotonergic Modulation. Integr Comp Biol 2021; 61:302-315. [PMID: 33974061 DOI: 10.1093/icb/icab051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Juvenile social experience, such as social isolation, has profound effects on communicative behavior, including signal production and reception. In the current study, we explored responsiveness to the neuromodulator serotonin as a potential mechanistic link between early life social isolation and auditory processing. The serotonergic system is sensitive to social isolation in many brain regions including the inferior colliculus (IC), an auditory midbrain nucleus. We investigated the effects of social experience on serotonergic responsiveness by measuring cFos, an immediate early gene product, in the IC of female mice. Serotonin was manipulated pharmacologically by administering fenfluramine, pCPA, or saline to mice that had undergone an extreme dichotomy in social experience after weaning: being housed in social groups versus individually. These mice were exposed to a 60-min recording of vocalizations from an opposite-sex interaction and perfused. Using immunohistochemistry, we measured the density of cFos-positive (cFos+) nuclei in the major subdivisions of the IC. Housing condition, drug treatment, and IC subregion all had a significant effect on cFos+ density. The central IC showed the highest density of cFos+ cells and also the most pronounced effects of housing condition and drug treatment. In the central IC, cFos+ density was higher following fenfluramine treatment than saline, and lower following pCPA treatment than fenfluramine. Individually housed mice showed a higher cFos+ density than socially housed mice in both of the pharmacological treatment groups, but not in the saline group. Drug treatment but not housing condition had strong effects on the behaviors of grooming, digging, rearing, and movement. Once the effects of drug condition were controlled, there were no across-individual correlations between cFos+ densities and behaviors. These findings suggest that the responses of auditory neurons to neuromodulation by serotonin are influenced by early life experience.
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Affiliation(s)
- Sarah E D Davis
- Department of Biology, Indiana University, 1001 East Third Street, Bloomington, IN 47401, USA
| | - Jack M Sansone
- Department of Biology, Indiana University, 1001 East Third Street, Bloomington, IN 47401, USA
| | - Laura M Hurley
- Department of Biology, Indiana University, 1001 East Third Street, Bloomington, IN 47401, USA.,Center for the Integrative Study of Animal Behavior, 409 N Park Ave, Bloomington, IN 47408, USA
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29
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Natural antioxidants enhance the power of physical and mental activities versus risk factors inducing progression of Alzheimer's disease in rats. Int Immunopharmacol 2021; 96:107729. [PMID: 33971493 DOI: 10.1016/j.intimp.2021.107729] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/02/2021] [Accepted: 04/25/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is a progressive neurodegenerative disease that is exacerbated by social isolation (SI) and protein malnutrition (PM). Antioxidants, physical and mental activities (Ph&M) can maintain cognitive functions and protect against dementia. OBJECTIVE To investigate the impact of Epigallocatechin-3-gallate (EGCG), Vitamin E (VE), Vitamin C (VC), and Selenium (Se), in enhancing the potential effect of Ph&M versus SI&PM as risk factors in the progression of AD in rats. METHODS Aluminum chloride (70 mg/kg, I.P for 5 weeks) was used to induce AD in rats that either normally fed or socially isolated and protein malnourished (SI&PM). Simultaneously, rats were weekly exposed to Ph&M either alone or in combination with EGCG (10 mg/kg, I.P), VC (400 mg/kg, P.O), VE (100 mg/kg, P.O), and Se (1 mg/kg, P.O). RESULTS The combination protocol of EGCG, VE, VC, and Se together with Ph&M significantly increased brain monoamines, superoxide dismutase (SOD), total antioxidant capacity (TAC) and brain-derived neurotrophic factor (BDNF) in AD, SI&PM and SI&PM/AD groups. Additionally, this regimen significantly mitigated brain acetylcholine esterase (ACHE), β-amyloid (Aβ), Tau protein, β-secretase, malondialdehyde (MDA), tumor necrosis factor-alpha (TNF-α), and Interleukin 1β (IL-1β) as well as DNA fragmentation. These biochemical findings were supported by the histopathological examinations of brain tissue. CONCLUSION The combination protocol of antioxidants with Ph&M activities mitigated SI&PM-induced progressive risk of AD.
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30
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Abramova O, Ushakova V, Zorkina Y, Zubkov E, Storozheva Z, Morozova A, Chekhonin V. The Behavior and Postnatal Development in Infant and Juvenile Rats After Ultrasound-Induced Chronic Prenatal Stress. Front Physiol 2021; 12:659366. [PMID: 33935805 PMCID: PMC8082110 DOI: 10.3389/fphys.2021.659366] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/23/2021] [Indexed: 01/30/2023] Open
Abstract
Fetal development is susceptible to environmental factors. One such factor is exposure to stress during pregnancy. The present study aimed to investigate the effects of chronic prenatal stress (PS) on the development and behavior of rat offspring during infancy and juvenile ages. Existing approaches to modeling prenatal stress on animals do not correlate with the main type of stress in pregnant women, namely psychological stress. We used a new stress paradigm in the experiment, namely, stress induced by exposure to variable frequency ultrasound (US), which acted on pregnant Wistar rats on gestational days 1–21. This type of stress in rodents can be comparable to psychological stress in humans. We assessed physical development, reflex maturation, motor ability development, anxious behavior, response to social novelty, and social play behavior in male and female offspring. Additionally, we investigated maternal behavior and the effect of neonatal handling (NH) on behavior. Prenatal stress did not affect postnatal developmental characteristics in rat pups, but prenatally stressed rats had higher body weight in early and adult age than controls. Prenatal exposure to a stressor increased anxiety in the open-field test (OF), changed social preferences in the social novelty test (SN), and impaired social play behavior in males. Neonatal handling reduced anxiety and restored social behavior, but evoked hyperactive behavior in rat pups. Maternal behavior did not change. Our study demonstrated for the first time that exposure to variable frequency ultrasound during pregnancy influences offspring development and impairs behavior, correlating with the effects of other types of stress during pregnancy in rodents. This supports the idea of using this exposure to model prenatal stress.
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Affiliation(s)
- Olga Abramova
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia.,Mental-health Clinic No. 1 Named After N.A. Alexeev of Moscow Healthcare Department, Moscow, Russia
| | - Valeria Ushakova
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia.,Mental-health Clinic No. 1 Named After N.A. Alexeev of Moscow Healthcare Department, Moscow, Russia.,Department of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Yana Zorkina
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia.,Mental-health Clinic No. 1 Named After N.A. Alexeev of Moscow Healthcare Department, Moscow, Russia
| | - Eugene Zubkov
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia
| | - Zinaida Storozheva
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia
| | - Anna Morozova
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia.,Mental-health Clinic No. 1 Named After N.A. Alexeev of Moscow Healthcare Department, Moscow, Russia
| | - Vladimir Chekhonin
- Department of Basic and Applied Neurobiology, V.P. Serbsky National Medical Research Center for Psychiatry and Narcology, Moscow, Russia.,Department of Medical Nanobiotechnology, Pirogov Russian National Research Medical University, Moscow, Russia
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31
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Lee CR, Chen A, Tye KM. The neural circuitry of social homeostasis: Consequences of acute versus chronic social isolation. Cell 2021; 184:1500-1516. [PMID: 33691140 PMCID: PMC8580010 DOI: 10.1016/j.cell.2021.02.028] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/29/2021] [Accepted: 02/09/2021] [Indexed: 11/22/2022]
Abstract
Social homeostasis is the ability of individuals to detect the quantity and quality of social contact, compare it to an established set-point in a command center, and adjust the effort expended to seek the optimal social contact expressed via an effector system. Social contact becomes a positive or negative valence stimulus when it is deficient or in excess, respectively. Chronic deficits lead to set-point adaptations such that reintroduction to the previous optimum is experienced as a surplus. Here, we build upon previous models for social homeostasis to include adaptations to lasting changes in environmental conditions, such as with chronic isolation.
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Affiliation(s)
- Christopher R Lee
- The Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Alon Chen
- Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Kay M Tye
- The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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32
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Bombardi C, Grandis A, Pivac N, Sagud M, Lucas G, Chagraoui A, Lemaire-Mayo V, De Deurwaerdère P, Di Giovanni G. Serotonin modulation of hippocampal functions: From anatomy to neurotherapeutics. PROGRESS IN BRAIN RESEARCH 2021; 261:83-158. [PMID: 33785139 DOI: 10.1016/bs.pbr.2021.01.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The hippocampal region receives a dense serotoninergic innervation originating from both medial and dorsal raphe nuclei. This innervation regulates hippocampal activity through the activation of distinct receptor families that are expressed in excitatory and inhibitory neurons, terminals of several afferent neurotransmitter systems, and glial cells. Preclinical and clinical studies indicate that hippocampal dysfunctions are involved in learning and memory deficits, dementia, Alzheimer's disease, epilepsy and mood disorders such as anxiety, depression and post-traumatic syndrome disorder, whereas the hippocampus participates also in the therapeutic mechanisms of numerous medicines. Not surprisingly, several drugs acting via 5-HT mechanisms are efficacious to some extent in some diseases and the link between 5-HT and the hippocampus although clear remains difficult to untangle. For this reason, we review reported data concerning the distribution and the functional roles of the 5-HT receptors in the hippocampal region in health and disease. The impact of the 5-HT systems on the hippocampal function is such that the research of new 5-HT mechanisms and drugs is still very active. It concerns notably drugs acting at the 5-HT1A,2A,2C,4,6 receptor subtypes, in addition to the already existing drugs including the selective serotonin reuptake inhibitors.
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Affiliation(s)
- Cristiano Bombardi
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy.
| | - Annamaria Grandis
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Nela Pivac
- Division of Molecular Medicine, Rudier Boskovic Institute, Zagreb, Croatia
| | - Marina Sagud
- Clinical Hospital Center Zagreb and School of Medicine University of Zagreb, Zagreb, Croatia
| | - Guillaume Lucas
- Neurocentre Magendie, INSERM 1215, Université de Bordeaux, Bordeaux, France
| | - Abdeslam Chagraoui
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Normandie University, UNIROUEN, INSERM U1239, Rouen, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France
| | - Valérie Lemaire-Mayo
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR 5287, Bordeaux, France
| | - Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR 5287, Bordeaux, France
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
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33
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Neonatal phencyclidine and social isolation in the rat: effects of clozapine on locomotor activity, social recognition, prepulse inhibition, and executive functions deficits. Psychopharmacology (Berl) 2021; 238:517-528. [PMID: 33169202 DOI: 10.1007/s00213-020-05700-y] [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] [Received: 05/27/2020] [Accepted: 10/30/2020] [Indexed: 12/26/2022]
Abstract
RATIONALE There is a need to develop animal models of schizophrenia-like behaviors that have both construct and predictive validity. Recently, a neonatal phencyclidine (PCP) and post-weaning social isolation dual-hit model was developed; however, its face and predictive validities need to be further investigated. OBJECTIVE The aims of this study were to extend the characterization of the behavioral changes occurring in the neonatal PCP and post-weaning social isolation dual-hit rat model and to evaluate the effects of chronic treatment with clozapine on signs related to schizophrenia. METHODS Male Wistar rat pups were treated with PCP (10 mg/kg s.c.) on postnatal days (PND) 7, 9, and 11. Starting from weaning, neonatal PCP-treated rat pups were socially isolated, while control saline-treated rats were group housed. At adulthood, rats were assessed using behavioral tasks evaluating locomotor activity, social recognition, prepulse inhibition, and reversal learning. Clozapine (3 mg/kg i.p.) was administered daily starting from a week before behavioral tests and until the end of the study. RESULTS Neonatal PCP-treated and post-weaning social isolated (PCP-SI) rats displayed persistent and robust locomotor hyperactivity as well as social recognition impairment. The latter could not be explained by variations in the motivation to interact with a juvenile rat. Weak-to-moderate deficits in prepulse inhibition and reversal learning were also observed. Chronic treatment with clozapine attenuated the observed locomotor hyperactivity and social recognition deficits. CONCLUSION The PCP-SI model presents enduring and robust deficits (hyperactivity and social recognition impairment) associated with positive symptoms and cognitive/social deficits of schizophrenia, respectively. These deficits are normalized by chronic treatment with clozapine, thereby confirming the predictive validity of this animal model.
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Gildawie KR, Ryll LM, Hexter JC, Peterzell S, Valentine AA, Brenhouse HC. A two-hit adversity model in developing rats reveals sex-specific impacts on prefrontal cortex structure and behavior. Dev Cogn Neurosci 2021; 48:100924. [PMID: 33515957 PMCID: PMC7847967 DOI: 10.1016/j.dcn.2021.100924] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023] Open
Abstract
Adversity early in life substantially impacts prefrontal cortex (PFC) development and vulnerability to later-life psychopathology. Importantly, repeated adverse experiences throughout childhood increase the risk for PFC-mediated behavioral deficits more commonly in women. Evidence from animal models points to effects of adversity on later-life neural and behavioral dysfunction; however, few studies have investigated the neurobiological underpinnings of sex-specific, long-term consequences of multiple developmental stressors. We modeled early life adversity in rats via maternal separation (postnatal day (P)2-20) and juvenile social isolation (P21-35). In adulthood, anxiety-like behavior was assessed in the elevated zero maze and the presence and structural integrity of PFC perineuronal nets (PNNs) enwrapping parvalbumin (PV)-expressing interneurons was quantified. PNNs are extracellular matrix structures formed during critical periods in postnatal development that play a key role in the plasticity of PV cells. We observed a female-specific effect of adversity on hyperactivity and risk-assessment behavior. Moreover, females – but not males – exposed to multiple hits of adversity demonstrated a reduction in PFC PV cells in adulthood. We also observed a sex-specific, potentiated reduction in PV + PNN structural integrity. These findings suggest a sex-specific impact of repeated adversity on neurostructural development and implicate PNNs as a contributor to associated behavioral dysfunction.
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Affiliation(s)
| | - Lilly M Ryll
- Department of Psychology, Northeastern University, Boston, MA, USA
| | - Jessica C Hexter
- Department of Psychology, Northeastern University, Boston, MA, USA
| | - Shayna Peterzell
- Department of Psychology, Northeastern University, Boston, MA, USA
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35
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Fontana BD, Müller TE, Cleal M, de Abreu MS, Norton WHJ, Demin KA, Amstislavskaya TG, Petersen EV, Kalueff AV, Parker MO, Rosemberg DB. Using zebrafish (Danio rerio) models to understand the critical role of social interactions in mental health and wellbeing. Prog Neurobiol 2021; 208:101993. [PMID: 33440208 DOI: 10.1016/j.pneurobio.2021.101993] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 11/24/2020] [Accepted: 01/05/2021] [Indexed: 02/07/2023]
Abstract
Social behavior represents a beneficial interaction between conspecifics that is critical for maintaining health and wellbeing. Dysfunctional or poor social interaction are associated with increased risk of physical (e.g., vascular) and psychiatric disorders (e.g., anxiety, depression, and substance abuse). Although the impact of negative and positive social interactions is well-studied, their underlying mechanisms remain poorly understood. Zebrafish have well-characterized social behavior phenotypes, high genetic homology with humans, relative experimental simplicity and the potential for high-throughput screens. Here, we discuss the use of zebrafish as a candidate model organism for studying the fundamental mechanisms underlying social interactions, as well as potential impacts of social isolation on human health and wellbeing. Overall, the growing utility of zebrafish models may improve our understanding of how the presence and absence of social interactions can differentially modulate various molecular and physiological biomarkers, as well as a wide range of other behaviors.
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Affiliation(s)
- Barbara D Fontana
- Brain and Behaviour Laboratory, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK.
| | - Talise E Müller
- Graduate Program in Biological Sciences: Toxicological Biochemistry, Natural and Exact Sciences Center, Federal University of Santa Maria, Santa Maria, RS, Brazil; Laboratory of Experimental Neuropscychobiology, Department of Biochemistry and Molecular Biology, Natural and Exact Sciences Center, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - Madeleine Cleal
- Brain and Behaviour Laboratory, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK
| | - Murilo S de Abreu
- Bioscience Institute, University of Passo Fundo, Passo Fundo, Brazil
| | - William H J Norton
- Department of Neuroscience, Psychology and Behaviour, College of Medicine, Biological Sciences and Psychology, University of Leicester, Leicester, UK; The International Zebrafish Neuroscience Research Consortium (ZNRC), Slidell, LA, USA
| | - Konstantin A Demin
- Institute of Experimental Medicine, Almazov National Medical Research Center, St. Petersburg, Russia; Institute of Translational Biomedicine, St. Petersburg State University, St. Petersburg, Russia; Scientific Research Center of Radiology and Surgical Technologies, St. Petersburg, Russia
| | | | - Elena V Petersen
- Laboratory of Molecular Biology, Neuroscience and Bioscreening, Moscow Institute of Physics and Technology, Moscow, Russia
| | - Allan V Kalueff
- School of Pharmacy, Southwest University, Beibei, Chongqing, China; Ural Federal University, Ekaterinburg, Russia
| | - Matthew O Parker
- Brain and Behaviour Laboratory, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK; The International Zebrafish Neuroscience Research Consortium (ZNRC), Slidell, LA, USA
| | - Denis B Rosemberg
- Graduate Program in Biological Sciences: Toxicological Biochemistry, Natural and Exact Sciences Center, Federal University of Santa Maria, Santa Maria, RS, Brazil; Laboratory of Experimental Neuropscychobiology, Department of Biochemistry and Molecular Biology, Natural and Exact Sciences Center, Federal University of Santa Maria, Santa Maria, RS, Brazil; The International Zebrafish Neuroscience Research Consortium (ZNRC), Slidell, LA, USA.
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Bendersky CJ, Milian AA, Andrus MD, De La Torre U, Walker DM. Long-Term Impacts of Post-weaning Social Isolation on Nucleus Accumbens Function. Front Psychiatry 2021; 12:745406. [PMID: 34616326 PMCID: PMC8488119 DOI: 10.3389/fpsyt.2021.745406] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 08/26/2021] [Indexed: 01/07/2023] Open
Abstract
Adolescence is a period of incredible change, especially within the brain's reward circuitry. Stress, including social isolation, during this time has profound effects on behaviors associated with reward and other neuropsychiatric disorders. Because the Nucleus Accumbens (NAc), is crucial to the integration of rewarding stimuli, the NAc is especially sensitive to disruptions by adolescent social isolation stress. This review highlights the long-term behavioral consequences of adolescent social isolation rearing on the NAc. It will discuss the cellular and molecular changes within the NAc that might underlie the long-term effects on behavior. When available sex-specific effects are discussed. Finally by mining publicly available data we identify, for the first time, key transcriptional profiles induced by adolescence social isolation in genes associated with dopamine receptor 1 and 2 medium spiny neurons and genes associated with cocaine self-administration. Together, this review provides a comprehensive discussion of the wide-ranging long-term impacts of adolescent social isolation on the dopaminergic system from molecules through behavior.
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Affiliation(s)
- Cari J Bendersky
- Department of Behavioral Neuroscience, Oregon Health and Science and University, Portland, OR, United States
| | - Allison A Milian
- Department of Behavioral Neuroscience, Oregon Health and Science and University, Portland, OR, United States
| | - Mason D Andrus
- Department of Behavioral Neuroscience, Oregon Health and Science and University, Portland, OR, United States
| | - Ubaldo De La Torre
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Oregon Health and Science University, Portland, OR, United States
| | - Deena M Walker
- Department of Behavioral Neuroscience, Oregon Health and Science and University, Portland, OR, United States
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Rivera DS, Lindsay CB, Oliva CA, Codocedo JF, Bozinovic F, Inestrosa NC. Effects of long-lasting social isolation and re-socialization on cognitive performance and brain activity: a longitudinal study in Octodon degus. Sci Rep 2020; 10:18315. [PMID: 33110163 PMCID: PMC7591540 DOI: 10.1038/s41598-020-75026-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/27/2020] [Indexed: 12/18/2022] Open
Abstract
Social isolation is considered a stressful situation that results in increased physiological reactivity to novel stimuli, altered behaviour, and impaired brain function. Here, we investigated the effects of long-term social isolation on working memory, spatial learning/memory, hippocampal synaptic transmission, and synaptic proteins in the brain of adult female and male Octodon degus. The strong similarity between degus and humans in social, metabolic, biochemical, and cognitive aspects, makes it a unique animal model that can be highly applicable for further social, emotional, cognitive, and aging studies. These animals were socially isolated from post-natal and post-weaning until adulthood. We also evaluated if re-socialization would be able to compensate for reactive stress responses in chronically stressed animals. We showed that long-term social isolation impaired the HPA axis negative feedback loop, which can be related to cognitive deficits observed in chronically stressed animals. Notably, re-socialization restored it. In addition, we measured physiological aspects of synaptic transmission, where chronically stressed males showed more efficient transmission but deficient plasticity, as the reverse was true on females. Finally, we analysed synaptic and canonical Wnt signalling proteins in the hypothalamus, hippocampus, and prefrontal cortex, finding both sex- and brain structure-dependent modulation, including transient and permanent changes dependent on stress treatment.
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Affiliation(s)
- Daniela S Rivera
- GEMA Center for Genomics, Ecology and Environment, Facultad de Estudios Interdisciplinarios, Universidad Mayor, Santiago, Chile.
| | - Carolina B Lindsay
- Center of Aging and Regeneration UC (CARE-UC), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carolina A Oliva
- Center of Aging and Regeneration UC (CARE-UC), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Francisco Codocedo
- Center of Aging and Regeneration UC (CARE-UC), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Francisco Bozinovic
- Center for Applied Ecology and Sustainability (CAPES), Departamento de Ecología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nibaldo C Inestrosa
- Center of Aging and Regeneration UC (CARE-UC), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile. .,Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile.
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38
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Shifts in broadband power and alpha peak frequency observed during long-term isolation. Sci Rep 2020; 10:17987. [PMID: 33093553 PMCID: PMC7581825 DOI: 10.1038/s41598-020-75127-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/12/2020] [Indexed: 12/23/2022] Open
Abstract
Prolonged periods of social isolation and spatial confinement do not only represent an issue that needs to be faced by a few astronauts during space missions, but can affect all of us as recently shown during pandemic situations. The fundamental question, how the brain adapts to periods of sensory deprivation and re-adapts to normality, has only received little attention. Here, we use eyes closed and eyes open resting-state electroencephalographic (EEG) recordings to investigate how neural activity is altered during 120 days of isolation in a spatially confined, space-analogue environment. After disentangling oscillatory patterns from 1/f activity, we show that isolation leads to a reduction in broadband power and a flattening of the 1/f spectral slope. Beyond that, we observed a reduction in alpha peak frequency during isolation, but did not find strong evidence for isolation-induced changes that are of oscillatory nature. Critically, all effects reversed upon release from isolation. These findings suggest that isolation and concomitant sensory deprivation lead to an enhanced cortical deactivation which might be explained by a reduction in the mean neuronal population firing rate.
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Love J, Zelikowsky M. Stress Varies Along the Social Density Continuum. Front Syst Neurosci 2020; 14:582985. [PMID: 33192349 PMCID: PMC7606998 DOI: 10.3389/fnsys.2020.582985] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 09/22/2020] [Indexed: 12/25/2022] Open
Abstract
Social stress is ubiquitous in the lives of social animals. While significant research has aimed to understand the specific forms of stress imparted by particular social interactions, less attention has been paid to understanding the behavioral effects and neural underpinnings of stress produced by the presence and magnitude of social interactions. However, in humans and rodents alike, chronically low and chronically high rates of social interaction are associated with a suite of mental health issues, suggesting the need for further research. Here, we review literature examining the behavioral and neurobiological findings associated with changing social density, focusing on research on chronic social isolation and chronic social crowding in rodent models, and synthesize findings in the context of the continuum of social density that can be experienced by social animals. Through this synthesis, we aim to both summarize the state of the field and describe promising avenues for future research that would more clearly define the broad effects of social interaction on the brain and behavior in mammals.
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Affiliation(s)
- Jay Love
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT, United States
| | - Moriel Zelikowsky
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT, United States
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Hernández-Arteaga E, Hernández-González M, Bonilla-Jaime H, Guevara MA, Ågmo A. Pubertal stress decreases sexual motivation and supresses the relation between cerebral theta rhythms and testosterone levels in adult male rats. Brain Res 2020; 1745:146937. [PMID: 32505750 DOI: 10.1016/j.brainres.2020.146937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 05/27/2020] [Accepted: 06/03/2020] [Indexed: 11/28/2022]
Abstract
This study evaluated the effect of stress during puberty on sexual motivation and the correlation between serum testosterone levels (T) and the absolute power of the theta electroencephalographic rhythms, recorded in the medial prefrontal cortex (mPFC) and basolateral amygdala (BLA) of adult male rats. Thirty males of the stressed group (SG, housed 1 per cage from days 25-50) and 30 controls (CG, housed 5 per cage), were tested in copulatory interactions at 90 days of age. The above mentioned physiological parameters were obtained during the awake-quiet state in a sub-group without sexual motivation (WSM, n = 15, stimulated with a nonreceptive female) and a sub-group with sexual motivation (SM, n = 15, stimulated with a receptive-female). Pearson correlations (r) between these parameters were calculated for each sub-group and brain structure and then compared between sub-groups. SG presented higher mount and intromission latencies than CG. While CG-WSM showed a positive r between T levels and theta band (0.23-0.59), those CG-SM presented a negative r (-0.23 to -0.67). An r that tended towards zero (-0.31 to 0.29) was obtained in both stressed sub-groups. This study shows that pubertal stress suppresses the relation between serum T levels and theta rhythms in the mPFC and BLA in adult male rats. This is one of the first studies evaluating the association between these two physiological parameters specifically in the context of sexual motivation; thus increasing our understanding of the effect of pubertal stress on prefrontal-amygdaline functioning during the sexually-motivated state in male rats.
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Affiliation(s)
| | | | - Herlinda Bonilla-Jaime
- Departamento de Biología de la Reproducción, Universidad Autónoma Metropolitana, Iztapalapa, Mexico
| | - Miguel Angel Guevara
- Instituto de Neurociencias, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | - Anders Ågmo
- Psychology Department, Tromsø University, Tromsø, Norway
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41
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Kaneda Y, Kawata A, Suzuki K, Matsunaga D, Yasumatsu M, Ishiwata T. Comparison of neurotransmitter levels, physiological conditions, and emotional behavior between isolation-housed rats with group-housed rats. Dev Psychobiol 2020; 63:452-460. [PMID: 32945540 DOI: 10.1002/dev.22036] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 07/17/2020] [Accepted: 08/25/2020] [Indexed: 11/11/2022]
Abstract
Brain monoaminergic neurotransmitters, such as dopamine (DA), serotonin (5-HT), and noradrenaline (NA), play crucial roles in neuronal and physiological functions, including social behaviors. Isolation housing may induce behavioral and neurochemical abnormalities in rats, although its influence on neurotransmitter levels remains obscure. This study investigated the influence of isolation- or group-housing on core body temperature (Tcore ), locomotor activity (ACT), emotional behavior, and neurotransmitter levels in male Wistar rats. Behavioral changes were monitored using the open field test (OFT) and social interaction test (SIT). After 4 weeks, brain tissues were collected to quantify 5-HT, DA, and NA concentrations. Body weight and basal Tcore during both the light and dark phase were higher in isolation-housed than in group-housed rats, although no significant difference was seen in ACT. No significant differences were observed during the OFT. Isolation-housed rats showed increased line crossing and decreased social behavior during the SIT. Isolation-housed rats exhibited decreased levels of 5-HT in the caudate putamen and amygdala, and elevated and decreased NA levels in the paraventricular hypothalamic nucleus and hippocampus, respectively. However, DA levels were unaffected. Thus, housing environments may affect brain areas that regulate various neuronal and physiological functions, such as memory, stress responses, and emotional behavior.
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Affiliation(s)
- Yuta Kaneda
- Graduate School of Community & Human Services, Rikkyo University, Saitama, Japan
| | - Akira Kawata
- Graduate School of Community & Human Services, Rikkyo University, Saitama, Japan
| | - Kota Suzuki
- Graduate School of Community & Human Services, Rikkyo University, Saitama, Japan
| | - Daisuke Matsunaga
- Graduate School of Community & Human Services, Rikkyo University, Saitama, Japan
| | - Mikinobu Yasumatsu
- Graduate School of Community & Human Services, Rikkyo University, Saitama, Japan
| | - Takayuki Ishiwata
- Graduate School of Community & Human Services, Rikkyo University, Saitama, Japan
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Keesom SM, Hurley LM. Silence, Solitude, and Serotonin: Neural Mechanisms Linking Hearing Loss and Social Isolation. Brain Sci 2020; 10:brainsci10060367. [PMID: 32545607 PMCID: PMC7349698 DOI: 10.3390/brainsci10060367] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/06/2020] [Accepted: 06/09/2020] [Indexed: 12/11/2022] Open
Abstract
For social animals that communicate acoustically, hearing loss and social isolation are factors that independently influence social behavior. In human subjects, hearing loss may also contribute to objective and subjective measures of social isolation. Although the behavioral relationship between hearing loss and social isolation is evident, there is little understanding of their interdependence at the level of neural systems. Separate lines of research have shown that social isolation and hearing loss independently target the serotonergic system in the rodent brain. These two factors affect both presynaptic and postsynaptic measures of serotonergic anatomy and function, highlighting the sensitivity of serotonergic pathways to both types of insult. The effects of deficits in both acoustic and social inputs are seen not only within the auditory system, but also in other brain regions, suggesting relatively extensive effects of these deficits on serotonergic regulatory systems. Serotonin plays a much-studied role in depression and anxiety, and may also influence several aspects of auditory cognition, including auditory attention and understanding speech in challenging listening conditions. These commonalities suggest that serotonergic pathways are worthy of further exploration as potential intervening mechanisms between the related conditions of hearing loss and social isolation, and the affective and cognitive dysfunctions that follow.
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Affiliation(s)
- Sarah M. Keesom
- Department of Biology, Utica College, Utica, NY 13502, USA
- Correspondence:
| | - Laura M. Hurley
- Center for the Integrative Study of Animal Behavior, Department of Biology, Indiana University, Bloomington, IN 47405, USA;
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43
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Takita M, Kikusui T. Early weaning augments the spontaneous release of dopamine in the amygdala but not the prefrontal cortex: an in vivo microdialysis study of male rats. Exp Anim 2020; 69:382-387. [PMID: 32350170 PMCID: PMC7677083 DOI: 10.1538/expanim.20-0015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Our early weaning schedule was associated with the emergence of trait anxiety in male
rodents performing an elevated plus maze but not an open-field test. We previously
reported that early weaning weakened excitatory neurotransmission to the amygdala from the
prefrontal cortex, where the mesocorticolimbic dopaminergic (DAergic) fiber terminates on
each. In this study, we investigated DAergic transmission in both these brain regions. The
extracellular levels of amygdalar DA in adulthood were two times higher in rats weaned at
16 days compared to those weaned at 30 days in both the home cage and the open-field. This
difference in extracellular DA levels was not apparent in the prefrontal cortex. The
concurrently measured locomotor and rearing behaviors did not vary according to the
weaning period and the probe-implanted region, respectively. These results suggest that
the effects of early weaning on DA tone appear to be specific to the amygdala and do not
represent ubiquitous upregulation as these changes were not observed in the prefrontal
cortex.
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Affiliation(s)
- Masatoshi Takita
- Human Informatics and Interaction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.,Center for Neuroscience and Biomedical Engineering, The University of Electro-Communications, 1-5-1 Choufuga-oka, Choufu, Tokyo 182-8585, Japan
| | - Takefumi Kikusui
- School of Veterinary Medicine, Azabu University, 1-17-71 Fuchinobe, Chuou-ku, Sagamihara, Kanagawa 252-5201, Japan
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44
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The Levels of Monoamines and Their Metabolites in the Brain Structures of Rats Subjected to Two- and Three-Month-Long Social Isolation. Bull Exp Biol Med 2020; 168:605-609. [PMID: 32249401 DOI: 10.1007/s10517-020-04761-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Indexed: 10/24/2022]
Abstract
The levels of monoamines and their metabolites in the brain structures of adult Wistar rats subjected to post-weaning social isolation for 2 and 3 months were analyzed by HPLC with electrochemical detection. We have previously shown that these rats consistently demonstrate increased aggressiveness and, as a rule, impairment of short-term habituation. Two-monthlong social isolation was accompanied by a reduction in serotonin content and its increased turnover judging from the 5-HIAA/5-HT ratio in the hippocampus; three-month-long isolation was associated with increased levels of serotonin and reduction in its turnover in the amygdala. At this term, the level of dopamine metabolite 3-methoxytyramine tended to increase in the amygdala. In the frontal cortex, a tendency to a decrease in 5-HT level was found. These findings suggest that more prolonged post-weaning social isolation is accompanied by reorganization of neural networks in the brain cortex, which can serve as the pathophysiological basis for psychoemotional disorders.
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45
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McCutcheon RA, Krystal JH, Howes OD. Dopamine and glutamate in schizophrenia: biology, symptoms and treatment. World Psychiatry 2020; 19:15-33. [PMID: 31922684 PMCID: PMC6953551 DOI: 10.1002/wps.20693] [Citation(s) in RCA: 268] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Glutamate and dopamine systems play distinct roles in terms of neuronal signalling, yet both have been proposed to contribute significantly to the pathophysiology of schizophrenia. In this paper we assess research that has implicated both systems in the aetiology of this disorder. We examine evidence from post-mortem, preclinical, pharmacological and in vivo neuroimaging studies. Pharmacological and preclinical studies implicate both systems, and in vivo imaging of the dopamine system has consistently identified elevated striatal dopamine synthesis and release capacity in schizophrenia. Imaging of the glutamate system and other aspects of research on the dopamine system have produced less consistent findings, potentially due to methodological limitations and the heterogeneity of the disorder. Converging evidence indicates that genetic and environmental risk factors for schizophrenia underlie disruption of glutamatergic and dopaminergic function. However, while genetic influences may directly underlie glutamatergic dysfunction, few genetic risk variants directly implicate the dopamine system, indicating that aberrant dopamine signalling is likely to be predominantly due to other factors. We discuss the neural circuits through which the two systems interact, and how their disruption may cause psychotic symptoms. We also discuss mechanisms through which existing treatments operate, and how recent research has highlighted opportunities for the development of novel pharmacological therapies. Finally, we consider outstanding questions for the field, including what remains unknown regarding the nature of glutamate and dopamine function in schizophrenia, and what needs to be achieved to make progress in developing new treatments.
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Affiliation(s)
- Robert A McCutcheon
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
- South London and Maudsley Foundation NHS Trust, Maudsley Hospital, London, UK
| | - John H Krystal
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- VA National Center for PTSD, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Oliver D Howes
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- MRC London Institute of Medical Sciences, Imperial College London, Hammersmith Hospital, London, UK
- South London and Maudsley Foundation NHS Trust, Maudsley Hospital, London, UK
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46
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Almeida J, Oliveira LA, Benini R, Crestani CC. Role of hippocampal nitrergic neurotransmission in behavioral and cardiovascular dysfunctions evoked by chronic social stress. Nitric Oxide 2020; 94:114-124. [DOI: 10.1016/j.niox.2019.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 11/18/2019] [Accepted: 11/18/2019] [Indexed: 12/21/2022]
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47
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Wang L, Nabi G, Zhang T, Wu Y, Li D. Potential Neurochemical and Neuroendocrine Effects of Social Distancing Amidst the COVID-19 Pandemic. Front Endocrinol (Lausanne) 2020; 11:582288. [PMID: 33162938 PMCID: PMC7580381 DOI: 10.3389/fendo.2020.582288] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 09/22/2020] [Indexed: 12/22/2022] Open
Affiliation(s)
| | | | | | - Yuefeng Wu
- *Correspondence: Yuefeng Wu, ; Dongming Li,
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48
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Sánchez-González A, Oliveras I, Río-Álamos C, Piludu MA, Gerbolés C, Tapias-Espinosa C, Tobeña A, Aznar S, Fernández-Teruel A. Dissociation between schizophrenia-relevant behavioral profiles and volumetric brain measures after long-lasting social isolation in Roman rats. Neurosci Res 2019; 155:43-55. [PMID: 31306676 DOI: 10.1016/j.neures.2019.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 07/02/2019] [Accepted: 07/05/2019] [Indexed: 11/29/2022]
Abstract
Social isolation rearing of rodents is an environmental manipulation known to induce or potentiate psychotic-like symptoms and attentional and cognitive impairments relevant for schizophrenia. When subjected to a 28-week isolation rearing treatment, the Roman high-avoidance (RHA-I) rats display the common behavioral social isolation syndrome, with prepulse inhibition (PPI) deficits, hyperactivity, increased anxiety responses and learning/memory impairments when compared to their low-avoidance (RLA-I) counterparts. These results add face validity to the RHA-I rats as an animal model for schizophrenia-relevant behavioral and cognitive profiles and confirm previous results. The aim here was to further investigate the neuroanatomical effects of the isolation rearing, estimated through volume differences in medial prefrontal cortex (mPFC), dorsal striatum (dSt) and hippocampus (HPC). Results showed a global increase in volume in the mPFC in the isolated rats of both strains, as well as strain effects (RLA > RHA) in the three brain regions. These unexpected but robust results, might have unveiled some kind of compensatory mechanisms due to the particularly long-lasting isolation rearing period, much longer than those commonly used in the literature (which usually range from 4 to 12 weeks).
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Affiliation(s)
- A Sánchez-González
- Dept. Psychiatry & Forensic Medicine, Institute of Neurosciences, Universidad Autónoma de Barcelona, Barcelona, Spain.
| | - I Oliveras
- Dept. Psychiatry & Forensic Medicine, Institute of Neurosciences, Universidad Autónoma de Barcelona, Barcelona, Spain
| | - C Río-Álamos
- Dept. Psychology, School of Medicine, Austral University of Chile, Valdivia, Chile
| | - M A Piludu
- Dept. of Life and Environmental Sciences, Section of Pharmaceutical, Pharmacological and Nutraceutical Sciences, University of Cagliari, Cagliari, Italy
| | - C Gerbolés
- Dept. Psychiatry & Forensic Medicine, Institute of Neurosciences, Universidad Autónoma de Barcelona, Barcelona, Spain
| | - C Tapias-Espinosa
- Dept. Psychiatry & Forensic Medicine, Institute of Neurosciences, Universidad Autónoma de Barcelona, Barcelona, Spain
| | - A Tobeña
- Dept. Psychiatry & Forensic Medicine, Institute of Neurosciences, Universidad Autónoma de Barcelona, Barcelona, Spain
| | - S Aznar
- Research Laboratory for Stereology and Neuroscience, Bispebjerg and Frederiksberg Hospitals, Copenhagen, Denmark.
| | - A Fernández-Teruel
- Dept. Psychiatry & Forensic Medicine, Institute of Neurosciences, Universidad Autónoma de Barcelona, Barcelona, Spain.
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49
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Fulford AJ, Keskes S. Limbic circuit connectivity and the stress response: New insights into the mammalian nociceptin peptide system. VITAMINS AND HORMONES 2019; 111:131-145. [PMID: 31421698 DOI: 10.1016/bs.vh.2019.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
Considerable progress has been made in understanding the neurobehavioral effects of nociceptin peptide (N/OFQ) and its NOP receptor. Recent interest has focused on its role in stress and cognition, with consideration of therapeutic potential in regard to anxiety and mood disorders. Research has interrogated the mechanisms of action of N/OFQ peptide in the context of stress-related behavior. We are interested in the endogenous role of N/OFQ and NOP receptor in terms of adaptation to chronic stress. Our research has highlighted the importance of associated limbic regions including the bed nucleus, extended amygdala, in addition to thalamic reticular nucleus as important sites for long-term adaptations in endogenous N/OFQ function in chronic stress. Such research raises interest in appreciation of extended limbic connections and novel pathways which allow us to reevaluate current understanding of stress neurocircuitry. Examination of endogenous N/OFQ-NOP receptor modulation of monoaminergic and amino acid transmitter systems in this extended limbic architecture will facilitate deeper understanding of the tonic control of behavior. Application of in vivo experimental approaches to models of abnormal neurodevelopment and heightened stress vulnerability in adulthood will enable the role of N/OFQ in complex neuropsychiatric disorders including schizophrenia and post-traumatic stress disorder to be defined.
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Affiliation(s)
| | - Sarah Keskes
- Centre for Applied Anatomy, University of Bristol, Bristol, United Kingdom; Keele University Medical School, Keele, United Kingdom
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50
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Karkhanis AN, Leach AC, Yorgason JT, Uneri A, Barth S, Niere F, Alexander NJ, Weiner JL, McCool BA, Raab-Graham KF, Ferris MJ, Jones SR. Chronic Social Isolation Stress during Peri-Adolescence Alters Presynaptic Dopamine Terminal Dynamics via Augmentation in Accumbal Dopamine Availability. ACS Chem Neurosci 2019; 10:2033-2044. [PMID: 30284806 DOI: 10.1021/acschemneuro.8b00360] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Chronic peri-adolescent stress in humans increases risk to develop a substance use disorder during adulthood. Rats reared in social isolation during peri-adolescence (aSI; 1 rat/cage) period show greater ethanol and cocaine intake compared to group housed (aGH; 4 rats/cage) rats. In addition, aSI rats have a heightened dopamine response in the nucleus accumbens (NAc) to rewarding and aversive stimuli. Furthermore, single pulse electrical stimulation in slices containing NAc core elicits greater dopamine release in aSI rats. Here, we further investigated dopamine release kinetics and machinery following aSI. Dopamine release, across a wide range of stimulation intensities and frequencies, was significantly greater in aSI rats. Interestingly, subthreshold intensity stimulations also resulted in measurable dopamine release in accumbal slices from aSI but not aGH rats. Extracellular [Ca2+] manipulations revealed augmented calcium sensitivity of dopamine release in aSI rats. The readily releasable pools of dopamine, examined by bath application of Ro-04-1284/000, a vesicular monoamine transporter 2 (VMAT2) inhibitor, were depleted faster in aGH rats. Western blot analysis of release machinery proteins (VMAT2, Synaptogyrin-3, Syntaxin-1, and Munc13-3) showed no difference between the two groups. Tyrosine hydroxylase (TH) protein expression levels, however, were elevated in aSI rats. The greater dopamine release could potentially be explained by higher levels of TH, the rate-limiting step for dopamine synthesis. This augmented responsivity of the dopamine system and heightened dopamine availability post-aSI may lead to an increased risk of addiction vulnerability.
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Affiliation(s)
- Anushree N. Karkhanis
- Department of Psychology and Developmental Exposure Alcohol Research Center, Binghamton University−SUNY, Binghamton, New York, United States
| | | | - Jordan T. Yorgason
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah, United States
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