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Zou X, Tang Q, Ojiro R, Ozawa S, Shobudani M, Sakamaki Y, Ebizuka Y, Jin M, Yoshida T, Shibutani M. Increased spontaneous activity and progressive suppression of adult neurogenesis in the hippocampus of rat offspring after maternal exposure to imidacloprid. Chem Biol Interact 2024; 399:111145. [PMID: 39002876 DOI: 10.1016/j.cbi.2024.111145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 07/01/2024] [Accepted: 07/10/2024] [Indexed: 07/15/2024]
Abstract
Imidacloprid (IMI) is a widely used neonicotinoid insecticide that poses risks for developmental neurotoxicity in mammals. The present study investigated the effects of maternal exposure to IMI on behaviors and adult neurogenesis in the hippocampal dentate gyrus (DG) of rat offspring. Dams were exposed to IMI via diet (83, 250, or 750 ppm in diet) from gestational day 6 until day 21 post-delivery on weaning, and offspring were maintained until adulthood on postnatal day 77. In the neurogenic niche, 750-ppm IMI decreased numbers of late-stage neural progenitor cells (NPCs) and post-mitotic immature granule cells by suppressing NPC proliferation and ERK1/2-FOS-mediated synaptic plasticity of granule cells on weaning. Suppressed reelin signaling might be responsible for the observed reductions of neurogenesis and synaptic plasticity. In adulthood, IMI at ≥ 250 ppm decreased neural stem cells by suppressing their proliferation and increasing apoptosis, and mature granule cells were reduced due to suppressed NPC differentiation. Behavioral tests revealed increased spontaneous activity in adulthood at 750 ppm. IMI decreased hippocampal acetylcholinesterase activity and Chrnb2 transcript levels in the DG on weaning and in adulthood. IMI increased numbers of astrocytes and M1-type microglia in the DG hilus, and upregulated neuroinflammation and oxidative stress-related genes on weaning. In adulthood, IMI increased malondialdehyde level and number of M1-type microglia, and downregulated neuroinflammation and oxidative stress-related genes. These results suggest that IMI persistently affected cholinergic signaling, induced neuroinflammation and oxidative stress during exposure, and increased sensitivity to oxidative stress after exposure in the hippocampus, causing hyperactivity and progressive suppression of neurogenesis in adulthood. The no-observed-adverse-effect level of IMI for offspring behaviors and hippocampal neurogenesis was determined to be 83 ppm (5.5-14.1 mg/kg body weight/day).
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Affiliation(s)
- Xinyu Zou
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Qian Tang
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Ryota Ojiro
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Shunsuke Ozawa
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Momoka Shobudani
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Yuri Sakamaki
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Yuri Ebizuka
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Meilan Jin
- Laboratory of Veterinary Pathology, College of Veterinary Medicine, Southwest University, No. 2 Tiansheng Road, BeiBei District, Chongqing, 400715, PR China.
| | - Toshinori Yoshida
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan; Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo, 183-8509, Japan.
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2
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Gillespie B, Panthi S, Sundram S, Hill RA. The impact of maternal immune activation on GABAergic interneuron development: A systematic review of rodent studies and their translational implications. Neurosci Biobehav Rev 2024; 156:105488. [PMID: 38042358 DOI: 10.1016/j.neubiorev.2023.105488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 11/09/2023] [Accepted: 11/27/2023] [Indexed: 12/04/2023]
Abstract
Mothers exposed to infections during pregnancy disproportionally birth children who develop autism and schizophrenia, disorders associated with altered GABAergic function. The maternal immune activation (MIA) model recapitulates this risk factor, with many studies also reporting disruptions to GABAergic interneuron expression, protein, cellular density and function. However, it is unclear if there are species, sex, age, region, or GABAergic subtype specific vulnerabilities to MIA. Furthermore, to fully comprehend the impact of MIA on the GABAergic system a synthesised account of molecular, cellular, electrophysiological and behavioural findings was required. To this end we conducted a systematic review of GABAergic interneuron changes in the MIA model, focusing on the prefrontal cortex and hippocampus. We reviewed 102 articles that revealed robust changes in a number of GABAergic markers that present as gestationally-specific, region-specific and sometimes sex-specific. Disruptions to GABAergic markers coincided with distinct behavioural phenotypes, including memory, sensorimotor gating, anxiety, and sociability. Findings suggest the MIA model is a valid tool for testing novel therapeutics designed to recover GABAergic function and associated behaviour.
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Affiliation(s)
- Brendan Gillespie
- Department of Psychiatry, School of Clinical Sciences, Monash University, Clayton, VIC 3168, Australia
| | - Sandesh Panthi
- Department of Psychiatry, School of Clinical Sciences, Monash University, Clayton, VIC 3168, Australia
| | - Suresh Sundram
- Department of Psychiatry, School of Clinical Sciences, Monash University, Clayton, VIC 3168, Australia
| | - Rachel A Hill
- Department of Psychiatry, School of Clinical Sciences, Monash University, Clayton, VIC 3168, Australia.
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3
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Lesh TA, Iosif AM, Tanase C, Vlasova RM, Ryan AM, Bennett J, Hogrefe CE, Maddock RJ, Geschwind DH, Van de Water J, McAllister AK, Styner MA, Bauman MD, Carter CS. Extracellular free water elevations are associated with brain volume and maternal cytokine response in a longitudinal nonhuman primate maternal immune activation model. Mol Psychiatry 2023; 28:4185-4194. [PMID: 37582858 PMCID: PMC10867284 DOI: 10.1038/s41380-023-02213-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 07/21/2023] [Accepted: 08/02/2023] [Indexed: 08/17/2023]
Abstract
Maternal infection has emerged as an important environmental risk factor for neurodevelopmental disorders, including schizophrenia and autism spectrum disorders. Animal model systems of maternal immune activation (MIA) suggest that the maternal immune response plays a significant role in the offspring's neurodevelopment and behavioral outcomes. Extracellular free water is a measure of freely diffusing water in the brain that may be associated with neuroinflammation and impacted by MIA. The present study evaluates the brain diffusion characteristics of male rhesus monkeys (Macaca mulatta) born to MIA-exposed dams (n = 14) treated with a modified form of the viral mimic polyinosinic:polycytidylic acid at the end of the first trimester. Control dams received saline injections at the end of the first trimester (n = 10) or were untreated (n = 4). Offspring underwent diffusion MRI scans at 6, 12, 24, 36, and 45 months. Offspring born to MIA-exposed dams showed significantly increased extracellular free water in cingulate cortex gray matter starting as early as 6 months of age and persisting through 45 months. In addition, offspring gray matter free water in this region was significantly correlated with the magnitude of the maternal IL-6 response in the MIA-exposed dams. Significant correlations between brain volume and extracellular free water in the MIA-exposed offspring also indicate converging, multimodal evidence of the impact of MIA on brain development. These findings provide strong evidence for the construct validity of the nonhuman primate MIA model as a system of relevance for investigating the pathophysiology of human neurodevelopmental psychiatric disorders. Elevated free water in individuals exposed to immune activation in utero could represent an early marker of a perturbed or vulnerable neurodevelopmental trajectory.
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Affiliation(s)
- Tyler A Lesh
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA
| | - Ana-Maria Iosif
- Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, CA, USA
| | - Costin Tanase
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA
| | - Roza M Vlasova
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - Amy M Ryan
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA
- MIND Institute, University of California, Davis, CA, USA
- California National Primate Research Center, Davis, CA, USA
| | - Jeffrey Bennett
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA
| | | | - Richard J Maddock
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA
| | - Daniel H Geschwind
- Neurogenetics Program, Department of Neurology, University of California, Los Angeles, CA, USA
| | - Judy Van de Water
- MIND Institute, University of California, Davis, CA, USA
- Rheumatology/Allergy and Clinical Immunology, University of California, Davis, CA, USA
| | - A Kimberley McAllister
- MIND Institute, University of California, Davis, CA, USA
- Center for Neuroscience, University of California, Davis, CA, USA
| | - Martin A Styner
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
| | - Melissa D Bauman
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA
- MIND Institute, University of California, Davis, CA, USA
- California National Primate Research Center, Davis, CA, USA
| | - Cameron S Carter
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA, USA.
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4
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Woods R, Lorusso J, Fletcher J, ElTaher H, McEwan F, Harris I, Kowash H, D'Souza SW, Harte M, Hager R, Glazier JD. Maternal immune activation and role of placenta in the prenatal programming of neurodevelopmental disorders. Neuronal Signal 2023; 7:NS20220064. [PMID: 37332846 PMCID: PMC10273029 DOI: 10.1042/ns20220064] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/16/2023] [Accepted: 05/17/2023] [Indexed: 06/20/2023] Open
Abstract
Maternal infection during pregnancy, leading to maternal immune activation (mIA) and cytokine release, increases the offspring risk of developing a variety of neurodevelopmental disorders (NDDs), including schizophrenia. Animal models have provided evidence to support these mechanistic links, with placental inflammatory responses and dysregulation of placental function implicated. This leads to changes in fetal brain cytokine balance and altered epigenetic regulation of key neurodevelopmental pathways. The prenatal timing of such mIA-evoked changes, and the accompanying fetal developmental responses to an altered in utero environment, will determine the scope of the impacts on neurodevelopmental processes. Such dysregulation can impart enduring neuropathological changes, which manifest subsequently in the postnatal period as altered neurodevelopmental behaviours in the offspring. Hence, elucidation of the functional changes that occur at the molecular level in the placenta is vital in improving our understanding of the mechanisms that underlie the pathogenesis of NDDs. This has notable relevance to the recent COVID-19 pandemic, where inflammatory responses in the placenta to SARS-CoV-2 infection during pregnancy and NDDs in early childhood have been reported. This review presents an integrated overview of these collective topics and describes the possible contribution of prenatal programming through placental effects as an underlying mechanism that links to NDD risk, underpinned by altered epigenetic regulation of neurodevelopmental pathways.
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Affiliation(s)
- Rebecca M. Woods
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Jarred M. Lorusso
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Jennifer Fletcher
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Medicine, Biology and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Heidi ElTaher
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Medicine, Biology and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
- Department of Physiology, Faculty of Medicine, Alexandria University, Egypt
| | - Francesca McEwan
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Isabella Harris
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Hager M. Kowash
- Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9WL, U.K
| | - Stephen W. D'Souza
- Division of Developmental Biology and Medicine, School of Medical Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9WL, U.K
| | - Michael Harte
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Medicine, Biology and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Reinmar Hager
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
| | - Jocelyn D. Glazier
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, U.K
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5
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Rong J, Yang Y, Liang M, Zhong H, Li Y, Zhu Y, Sha S, Chen L, Zhou R. Neonatal inflammation increases hippocampal KCC2 expression through methylation-mediated TGF-β1 downregulation leading to impaired hippocampal cognitive function and synaptic plasticity in adult mice. J Neuroinflammation 2023; 20:15. [PMID: 36691035 PMCID: PMC9872321 DOI: 10.1186/s12974-023-02697-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/12/2023] [Indexed: 01/25/2023] Open
Abstract
The mechanisms by which neonatal inflammation leads to cognitive deficits in adulthood remain poorly understood. Inhibitory GABAergic synaptic transmission plays a vital role in controlling learning, memory and synaptic plasticity. Since early-life inflammation has been reported to adversely affect the GABAergic synaptic transmission, the aim of this study was to investigate whether and how neonatal inflammation affects GABAergic synaptic transmission resulting in cognitive impairment. Neonatal mice received a daily subcutaneous injection of lipopolysaccharide (LPS, 50 μg/kg) or saline on postnatal days 3-5. It was found that blocking GABAergic synaptic transmission reversed the deficit in hippocampus-dependent memory or the induction failure of long-term potentiation in the dorsal CA1 in adult LPS mice. An increase of mIPSCs amplitude was further detected in adult LPS mice indicative of postsynaptic potentiation of GABAergic transmission. Additionally, neonatal LPS resulted in the increased expression and function of K+-Cl--cotransporter 2 (KCC2) and the decreased expression of transforming growth factor-beta 1 (TGF-β1) in the dorsal CA1 during adulthood. The local TGF-β1 overexpression improved KCC2 expression and function, synaptic plasticity and memory of adult LPS mice. Adult LPS mice show hypermethylation of TGFb1 promoter and negatively correlate with reduced TGF-β1 transcripts. 5-Aza-deoxycytidine restored the changes in TGFb1 promoter methylation and TGF-β1 expression. Altogether, the results suggest that hypermethylation-induced reduction of TGF-β1 leads to enhanced GABAergic synaptic inhibition through increased KCC2 expression, which is a underlying mechanism of neonatal inflammation-induced hippocampus-dependent memory impairment in adult mice.
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Affiliation(s)
- Jing Rong
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Yang Yang
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Min Liang
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Haiquan Zhong
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Yingchun Li
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Yichao Zhu
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Sha Sha
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Lei Chen
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
| | - Rong Zhou
- grid.89957.3a0000 0000 9255 8984Department of Physiology, Nanjing Medical University, Longmian Avenue 101, Jiangning District, Nanjing, 211166 Jiangsu China
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6
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Zhong H, Rong J, Yang Y, Liang M, Li Y, Zhou R. Neonatal inflammation via persistent TGF-β1 downregulation decreases GABA AR expression in basolateral amygdala leading to the imbalance of the local excitation-inhibition circuits and anxiety-like phenotype in adult mice. Neurobiol Dis 2022; 169:105745. [PMID: 35513229 DOI: 10.1016/j.nbd.2022.105745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 11/29/2022] Open
Abstract
Neonatal inflammation can increase the risk of anxiety disorder in adulthood. The balance between glutamatergic excitatory and GABAergic inhibitory transmissions in the basolateral amygdala (BLA) plays a vital role in controlling anxiety state. Based on the reports that early-life inflammation had adverse effects on GABAergic system, the aim of this study was to investigate whether and how neonatal inflammation affects excitatory-inhibitory circuits in the BLA resulting in anxiety disorder. Neonatal mice received a daily subcutaneous injection of lipopolysaccharide (LPS, 50 μg/kg) or saline on postnatal days 3-5. LPS-treated mice developed anxiety behaviors accompanied by the hyperactivity of adrenal axis in adulthood. Electrophysiological study revealed the increase of postsynaptic neuronal excitability in the cortical-BLA excitatory synapses of LPS mice which could be recovered by bath-application of GABAAR agonist suggesting the impairment of GABAergic system in LPS mice. Compared with controls, GABAARα2 subunit expression and density of GABA-evoked current in BLA principal neurons were reduced in LPS mice. Additionally, neonatal LPS treatment resulted in the down-regulation of transforming growth factor-beta 1 (TGF-β1) expression and PKC signaling pathway in the adult BLA. The local TGF-β1 overexpression in the BLA improved GABAARα2 expression via up-regulating the activity of PKC signaling, which corrected GABAAR-mediated inhibition leading to the abolishment of anxiety-like change in adrenal axis regulation and behaviors in LPS mice. These data suggest the persistent TGF-β1deficit induces the down-regulation of GABAARα2 expression and subsequent disruption of the excitation-inhibition balance in the BLA circuits, which is the important mechanisms of neonatal inflammation-induced anxiety disorder.
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Affiliation(s)
- Haiquan Zhong
- Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Jing Rong
- Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Yang Yang
- Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Min Liang
- Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Yingchun Li
- Department of Physiology, Nanjing Medical University, Nanjing 211166, China
| | - Rong Zhou
- Department of Physiology, Nanjing Medical University, Nanjing 211166, China.
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7
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Sánchez-Hidalgo AC, Martín-Cuevas C, Crespo-Facorro B, Garrido-Torres N. Reelin Alterations, Behavioral Phenotypes, and Brain Anomalies in Schizophrenia: A Systematic Review of Insights From Rodent Models. Front Neuroanat 2022; 16:844737. [PMID: 35401125 PMCID: PMC8986979 DOI: 10.3389/fnana.2022.844737] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/14/2022] [Indexed: 12/09/2022] Open
Abstract
Reelin is an extracellular matrix glycoprotein reduced in brain regions (the prefrontal cortex and the hippocampus) of patients with schizophrenia. There are diverse rodent models of schizophrenia that mimic patient symptoms based on various causal theories; however, likely shared reelin alterations have not yet been systematically assessed in those models. A systematic review of the literature was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model. Articles focused on psychotic disorders or schizophrenia and their relationship with reelin in rodent models were selected. Data (first author, publication year, results, both open field and prepulse inhibition test results, and type of reelin alteration) were extracted in duplicate by two independent reviewers. The 37 reviewed articles reported about various schizophrenia models and their reelin alterations, brain morphology, and behavioral defects. We conclude that reelin is an altered preclinical biomarker common to all models included, mainly prenatal or genetic models, and a key protein in schizophrenia disease, making the reelin signaling pathway in prenatal stages a target of special interest for future preclinical and clinical studies. All models presented at least one of the four described reelin alteration types. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021210568], identifier [CRD42021210568].
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Affiliation(s)
- Ana C. Sánchez-Hidalgo
- Spanish Network for Research in Mental Health (CIBERSAM), Madrid, Spain
- Seville Biomedical Research Centre (IBiS), Seville, Spain
| | - Celia Martín-Cuevas
- Spanish Network for Research in Mental Health (CIBERSAM), Madrid, Spain
- Seville Biomedical Research Centre (IBiS), Seville, Spain
| | - Benedicto Crespo-Facorro
- Spanish Network for Research in Mental Health (CIBERSAM), Madrid, Spain
- Seville Biomedical Research Centre (IBiS), Seville, Spain
- Department of Psychiatry, School of Medicine, University Hospital Virgen del Rocío-IBiS, Seville, Spain
- *Correspondence: Benedicto Crespo-Facorro,
| | - Nathalia Garrido-Torres
- Spanish Network for Research in Mental Health (CIBERSAM), Madrid, Spain
- Seville Biomedical Research Centre (IBiS), Seville, Spain
- Department of Psychiatry, School of Medicine, University Hospital Virgen del Rocío-IBiS, Seville, Spain
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8
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Stress induced microglial activation contributes to depression. Pharmacol Res 2022; 179:106145. [DOI: 10.1016/j.phrs.2022.106145] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 02/08/2022] [Accepted: 02/22/2022] [Indexed: 02/06/2023]
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9
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Zakharova L, Sharova V, Izvolskaia M. Mechanisms of Reciprocal Regulation of Gonadotropin-Releasing Hormone (GnRH)-Producing and Immune Systems: The Role of GnRH, Cytokines and Their Receptors in Early Ontogenesis in Normal and Pathological Conditions. Int J Mol Sci 2020; 22:ijms22010114. [PMID: 33374337 PMCID: PMC7795970 DOI: 10.3390/ijms22010114] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 12/18/2020] [Accepted: 12/22/2020] [Indexed: 12/15/2022] Open
Abstract
Different aspects of the reciprocal regulatory influence on the development of gonadotropin-releasing hormone (GnRH)-producing- and immune systems in the perinatal ontogenesis and their functioning in adults in normal and pathological conditions are discussed. The influence of GnRH on the development of the immune system, on the one hand, and the influence of proinflammatory cytokines on the development of the hypothalamic-pituitary-gonadal system, on the other hand, and their functioning in adult offspring are analyzed. We have focused on the effects of GnRH on the formation and functional activity of the thymus, as the central organ of the immune system, in the perinatal period. The main mechanisms of reciprocal regulation of these systems are discussed. The reproductive health of an individual is programmed by the establishment and development of physiological systems during critical periods. Regulatory epigenetic mechanisms of development are not strictly genetically controlled. These processes are characterized by a high sensitivity to various regulatory factors, which provides possible corrections for disorders.
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10
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Holingue C, Budavari AC, Rodriguez KM, Zisman CR, Windheim G, Fallin MD. Sex Differences in the Gut-Brain Axis: Implications for Mental Health. Curr Psychiatry Rep 2020; 22:83. [PMID: 33216233 PMCID: PMC7717677 DOI: 10.1007/s11920-020-01202-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/20/2020] [Indexed: 12/17/2022]
Abstract
PURPOSE OF REVIEW The purpose of this article is to highlight how sex differences in the gut-brain axis may contribute to the discrepancies in incidence of neurodevelopmental, psychiatric, and neurodegenerative disorders between females and males. We focus on autism spectrum disorder, psychotic disorders, stress and anxiety disorders, depression, Alzheimer's disease, and Parkinson's disease and additionally discuss the comorbidity between inflammatory bowel disorder and mental health disorders. RECENT FINDINGS Human and animal studies show that sex may modify the relationship between the gut or immune system and brain and behavior. Sex also appears to modify the effect of microbial treatments such as probiotics and antibiotics on brain and behavior. There is emerging evidence that assessing the role of sex in the gut-brain axis may help elucidate the etiology of and identify effective treatments for neurodevelopmental, psychiatric, and neurodegenerative disorders.
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Affiliation(s)
- Calliope Holingue
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA.
- Department of Neuropsychology, Kennedy Krieger Institute, Baltimore, MD, USA.
- , Baltimore, USA.
| | - Alexa Curhan Budavari
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Katrina M Rodriguez
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Corina R Zisman
- Section on the Neurobiology of Fear and Anxiety, National Institute of Mental Health, Bethesda, MD, USA
| | - Grace Windheim
- Public Health Studies, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - M Daniele Fallin
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
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11
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Brain Structural and Functional Alterations in Mice Prenatally Exposed to LPS Are Only Partially Rescued by Anti-Inflammatory Treatment. Brain Sci 2020; 10:brainsci10090620. [PMID: 32906830 PMCID: PMC7564777 DOI: 10.3390/brainsci10090620] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 08/30/2020] [Accepted: 09/03/2020] [Indexed: 12/12/2022] Open
Abstract
Aberrant immune activity during neurodevelopment could participate in the generation of neurological dysfunctions characteristic of several neurodevelopmental disorders (NDDs). Numerous epidemiological studies have shown a link between maternal infections and NDDs risk; animal models of maternal immune activation (MIA) have confirmed this association. Activation of maternal immune system during pregnancy induces behavioral and functional alterations in offspring but the biological mechanisms at the basis of these effects are still poorly understood. In this study, we investigated the effects of prenatal lipopolysaccharide (LPS) exposure in peripheral and central inflammation, cortical cytoarchitecture and behavior of offspring (LPS-mice). LPS-mice reported a significant increase in interleukin-1β (IL-1β) serum level, glial fibrillary acidic protein (GFAP)- and ionized calcium-binding adapter molecule 1 (Iba1)-positive cells in the cortex. Furthermore, cytoarchitecture analysis in specific brain areas, showed aberrant alterations in minicolumns’ organization in LPS-mice adult brain. In addition, we demonstrated that LPS-mice presented behavioral alterations throughout life. In order to better understand biological mechanisms whereby LPS induced these alterations, dams were treated with meloxicam. We demonstrated for the first time that exposure to LPS throughout pregnancy induces structural permanent alterations in offspring brain. LPS-mice also present severe behavioral impairments. Preventive treatment with meloxicam reduced inflammation in offspring but did not rescue them from structural and behavioral alterations.
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12
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Prenatal exposure to lipopolysaccharide induces changes in the circadian clock in the SCN and AA-NAT activity in the pineal gland. Brain Res 2020; 1743:146952. [DOI: 10.1016/j.brainres.2020.146952] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/02/2020] [Accepted: 06/06/2020] [Indexed: 11/20/2022]
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13
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Pires JM, Foresti ML, Silva CS, Rêgo DB, Calió ML, Mosini AC, Nakamura TKE, Leslie ATF, Mello LE. Lipopolysaccharide-Induced Systemic Inflammation in the Neonatal Period Increases Microglial Density and Oxidative Stress in the Cerebellum of Adult Rats. Front Cell Neurosci 2020; 14:142. [PMID: 32581717 PMCID: PMC7283979 DOI: 10.3389/fncel.2020.00142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 04/28/2020] [Indexed: 01/09/2023] Open
Abstract
Inflammatory processes occurring in the perinatal period may affect different brain regions, resulting in neurologic sequelae. Injection of lipopolysaccharide (LPS) at different neurodevelopmental stages produces long-term consequences in several brain structures, but there is scarce evidence regarding alterations in the cerebellum. The aim of this study was to evaluate the long-term consequences on the cerebellum of a systemic inflammatory process induced by neonatal LPS injection. For this, neonatal rats were randomly assigned to three different groups: naïve, sham, and LPS. Saline (sham group) or LPS solution (1 mg/kg) was intraperitoneally injected on alternate postnatal days (PN) PN1, PN3, PN5, and PN7. Spontaneous activity was evaluated with the open field test in adulthood. The cerebellum was evaluated for different parameters: microglial and Purkinje cell densities, oxidative stress levels, and tumor necrosis factor alpha (TNF-α) mRNA expression. Our results show that administration of LPS did not result in altered spontaneous activity in adult animals. Our data also indicate increased oxidative stress in the cerebellum, as evidenced by an increase in superoxide fluorescence by dihydroethidium (DHE) indicator. Stereological analyses indicated increased microglial density in the cerebellum that was not accompanied by Purkinje cell loss or altered TNF-α expression in adult animals. Interestingly, Purkinje cells ectopically positioned in the granular and molecular layers of the cerebellum were observed in animals of the LPS group. Our data suggest that neonatal LPS exposure causes persistent cellular and molecular changes to the cerebellum, indicating the susceptibility of this region to systemic inflammatory insults in infancy. Further investigation of the consequences of these changes and the development of strategies to avoid those should be subject of future studies.
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Affiliation(s)
| | - Maira Licia Foresti
- Physiology Department, Universidade Federal de São Paulo, São Paulo, Brazil.,Instituto D'Or de Pesquisa e Ensino, Rio de Janeiro, Brazil
| | | | | | | | - Amanda Cristina Mosini
- Physiology Department, Universidade Federal de São Paulo, São Paulo, Brazil.,Associação Brasileira de Epilepsia, São Paulo, Brazil
| | | | | | - Luiz Eugênio Mello
- Physiology Department, Universidade Federal de São Paulo, São Paulo, Brazil.,Instituto D'Or de Pesquisa e Ensino, Rio de Janeiro, Brazil
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14
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Costa LG, Cole TB, Dao K, Chang YC, Coburn J, Garrick JM. Effects of air pollution on the nervous system and its possible role in neurodevelopmental and neurodegenerative disorders. Pharmacol Ther 2020; 210:107523. [PMID: 32165138 PMCID: PMC7245732 DOI: 10.1016/j.pharmthera.2020.107523] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 02/25/2020] [Indexed: 02/06/2023]
Abstract
Recent extensive evidence indicates that air pollution, in addition to causing respiratory and cardiovascular diseases, may also negatively affect the brain and contribute to central nervous system diseases. Air pollution is comprised of ambient particulate matter (PM) of different sizes, gases, organic compounds, and metals. An important contributor to PM is represented by traffic-related air pollution, mostly ascribed to diesel exhaust (DE). Epidemiological and animal studies have shown that exposure to air pollution may be associated with multiple adverse effects on the central nervous system. In addition to a variety of behavioral abnormalities, the most prominent effects caused by air pollution are oxidative stress and neuro-inflammation, which are seen in both humans and animals, and are supported by in vitro studies. Among factors which can affect neurotoxic outcomes, age is considered most relevant. Human and animal studies suggest that air pollution may cause developmental neurotoxicity, and may contribute to the etiology of neurodevelopmental disorders, including autism spectrum disorder. In addition, air pollution exposure has been associated with increased expression of markers of neurodegenerative disease pathologies, such as alpha-synuclein or beta-amyloid, and may thus contribute to the etiopathogenesis of neurodegenerative diseases, particularly Alzheimer's disease and Parkinson's disease.
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Affiliation(s)
- Lucio G Costa
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA; Dept. of Medicine & Surgery, University of Parma, Italy.
| | - Toby B Cole
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA; Center on Human Development and Disability, University of Washington, Seattle, WA, USA
| | - Khoi Dao
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Yu-Chi Chang
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Jacki Coburn
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Jacqueline M Garrick
- Dept. of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
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15
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Acetylcholine receptor agonist effect on seizure activity and GABAergic mechanisms involved in prolonged febrile seizure development in an animal model. Brain Res Bull 2019; 149:203-207. [DOI: 10.1016/j.brainresbull.2019.04.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 04/17/2019] [Accepted: 04/24/2019] [Indexed: 12/21/2022]
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16
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Da Silva T, Hafizi S, Rusjan PM, Houle S, Wilson AA, Prce I, Sailasuta N, Mizrahi R. GABA levels and TSPO expression in people at clinical high risk for psychosis and healthy volunteers: a PET-MRS study. J Psychiatry Neurosci 2019; 44:111-119. [PMID: 30255837 PMCID: PMC6397035 DOI: 10.1503/jpn.170201] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND γ-Aminobutyric acidergic (GABAergic) dysfunction and immune activation have been implicated in the pathophysiology of schizophrenia. Preclinical evidence suggests that inflammation-related abnormalities may contribute to GABAergic alterations in the brain, but this has never been investigated in vivo in humans. In this multimodal imaging study, we quantified cerebral GABA plus macromolecule (GABA+) levels in antipsychotic-naive people at clinical high risk for psychosis and in healthy volunteers. We investigated for the first time the association between GABA+ levels and expression of translocator protein 18 kDa (TSPO; a marker of microglial activation) using positron emission tomography (PET). METHODS Thirty-five people at clinical high risk for psychosis and 18 healthy volunteers underwent 3 T proton magnetic resonance spectroscopy to obtain GABA+ levels in the medial prefrontal cortex (mPFC). A subset (29 people at clinical high risk for psychosis and 15 healthy volunteers) also underwent a high-resolution [18F]FEPPA PET scan to quantify TSPO expression. Each participant was genotyped for the TSPO rs6971 polymorphism. RESULTS We found that GABA+ levels were significantly associated with TSPO expression in the mPFC (F1,40 = 10.45, p = 0.002). We found no significant differences in GABA+ levels in the mPFC (F1,51 = 0.00, p > 0.99) between people at clinical high risk for psychosis and healthy volunteers. We found no significant correlations between GABA+ levels or residuals of the association with TSPO expression and the severity of prodromal symptoms or cognition. LIMITATIONS Given the cross-sectional nature of this study, we could determine no cause-and-effect relationships for GABA alterations and TSPO expression. CONCLUSION Our findings suggest that TSPO expression is negatively associated with GABA+ levels in the prefrontal cortex, independent of disease status.
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Affiliation(s)
- Tania Da Silva
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Sina Hafizi
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Pablo M Rusjan
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Sylvain Houle
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Alan A Wilson
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Ivana Prce
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Napapon Sailasuta
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
| | - Romina Mizrahi
- From the Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Silva, Hafizi, Rusjan, Houle, Wilson, Prce, Sailasuta, Mizrahi); the Institute of Medical Science, University of Toronto, Toronto, Ont., Canada (Silva, Rusjan, Mizrahi); the Department of Psychiatry, University of Toronto, Toronto, Ont., Canada (Rusjan, Houle, Wilson, Mizrahi); and the Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ont., Canada (Rusjan, Houle, Sailasuta, Mizrahi)
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17
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Ignatiuk VM, Izvolskaya MS, Sharova VS, Voronova SN, Zakharova LA. Disruptions in the reproductive system of female rats after prenatal lipopolysaccharide-induced immunological stress: role of sex steroids. Stress 2019; 22:133-141. [PMID: 30369279 DOI: 10.1080/10253890.2018.1508440] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Stress signals during fetal or early postnatal periods may disorganize reproductive axis development at different levels. This study was aimed to test the hypothesis that prenatal immunological stress induced by bacterial endotoxin, lipopolysaccharide (LPS), has impact on structure and function of the reproductive system in female offspring. Adult female Wistar rats were divided into two groups, a control group (n = 5) and a LPS group (n = 12). Rats were injected with LPS 50 μg/kg body or 0.9% saline intraperitoneally on the 12th day of pregnancy. After birth the female pups (n = 20 in each group) were divided into four groups: (group 1) 0.9% saline prenatally, sesame oil (vehicle) postnatally; (group 2) LPS prenatally, sesame oil postnatally; (group 3) LPS prenatally, fulvestrant postnatally; (group 4) LPS prenatally, flutamide postnatally. Pups were injected subcutaneously into the neck with fulvestrant (estrogen receptor antagonist), 1.5 mg/kg in sesame oil, from postnatal day (PND) 5 to PND14; or flutamide (androgen receptor antagonist), 20 mg/kg in sesame oil, from PND14 to PND30. Rats of the control group were injected with sesame oil during the same time period. Parameters were evaluated by ELISA (serum estradiol and testosterone) and ovarian histology. The main findings were: (1) prenatal stress during the critical period resulted in delayed vaginal opening, decreased body weight and serum concentrations of sex steroids, and significant disorders in ovarian development; (2) postnatal estradiol and testosterone antagonist treatments decreased follicular atresia through increasing the number of healthy follicles and restored endogenous steroid production. Lay summaryImmunological stress, caused by simulating infection through exposure to a bacterial toxin (LPS), during a critical period of fetal development in laboratory rats results in delayed reproductive maturity, decreased body weight and decreased secretion of sex steroids in female offspring, and abnormalities in the ovaries like those in polycystic ovarian syndrome. These prenatally toxin-induced sexual disorders in females could be corrected by estradiol/testosterone antagonists during the postnatal period.
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Affiliation(s)
- V M Ignatiuk
- a Moscow State University GSP-1 , Moscow , Russia
| | - M S Izvolskaya
- b Koltsov Institute of Developmental Biology , Russian Academy of Sciences , Moscow , Russia
| | - V S Sharova
- b Koltsov Institute of Developmental Biology , Russian Academy of Sciences , Moscow , Russia
| | - S N Voronova
- b Koltsov Institute of Developmental Biology , Russian Academy of Sciences , Moscow , Russia
| | - L A Zakharova
- b Koltsov Institute of Developmental Biology , Russian Academy of Sciences , Moscow , Russia
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18
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Bergdolt L, Dunaevsky A. Brain changes in a maternal immune activation model of neurodevelopmental brain disorders. Prog Neurobiol 2018; 175:1-19. [PMID: 30590095 DOI: 10.1016/j.pneurobio.2018.12.002] [Citation(s) in RCA: 154] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 12/13/2018] [Accepted: 12/20/2018] [Indexed: 12/11/2022]
Abstract
The developing brain is sensitive to a variety of insults. Epidemiological studies have identified prenatal exposure to infection as a risk factor for a range of neurological disorders, including autism spectrum disorder and schizophrenia. Animal models corroborate this association and have been used to probe the contribution of gene-environment interactions to the etiology of neurodevelopmental disorders. Here we review the behavior and brain phenotypes that have been characterized in MIA offspring, including the studies that have looked at the interaction between maternal immune activation and genetic risk factors for autism spectrum disorder or schizophrenia. These phenotypes include behaviors relevant to autism, schizophrenia, and other neurological disorders, alterations in brain anatomy, and structural and functional neuronal impairments. The link between maternal infection and these phenotypic changes is not fully understood, but there is increasing evidence that maternal immune activation induces prolonged immune alterations in the offspring's brain which could underlie epigenetic alterations which in turn may mediate the behavior and brain changes. These concepts will be discussed followed by a summary of the pharmacological interventions that have been tested in the maternal immune activation model.
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Affiliation(s)
- Lara Bergdolt
- University of Nebraska Medical Center, Neurological Sciences, 985960 Nebraska Medical Center, 68105, Omaha, NE, United States
| | - Anna Dunaevsky
- University of Nebraska Medical Center, Neurological Sciences, 985960 Nebraska Medical Center, 68105, Omaha, NE, United States.
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19
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Izvolskaia MS, Sharova VS, Ignatiuk VM, Voronova SN, Zakharova LA. Abolition of prenatal lipopolysaccharide-induced reproductive disorders in rat male offspring by fulvestrant. Andrologia 2018; 51:e13204. [DOI: 10.1111/and.13204] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 10/18/2018] [Accepted: 10/29/2018] [Indexed: 01/16/2023] Open
Affiliation(s)
- Marina S. Izvolskaia
- Koltsov Institute of Developmental Biology; Russian Academy of Sciences; Moscow Russia
| | - Victoria S. Sharova
- Koltsov Institute of Developmental Biology; Russian Academy of Sciences; Moscow Russia
| | | | - Svetlana N. Voronova
- Koltsov Institute of Developmental Biology; Russian Academy of Sciences; Moscow Russia
| | - Liudmila A. Zakharova
- Koltsov Institute of Developmental Biology; Russian Academy of Sciences; Moscow Russia
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20
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Erbas O, Erdogan MA, Khalilnezhad A, Gürkan FT, Yiğittürk G, Meral A, Taskiran D. Neurobehavioral effects of long‐term maternal fructose intake in rat offspring. Int J Dev Neurosci 2018; 69:68-79. [DOI: 10.1016/j.ijdevneu.2018.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 01/29/2023] Open
Affiliation(s)
- Oytun Erbas
- Istanbul Bilim University School of MedicineDepartment of PhysiologyIstanbulTurkey
| | | | | | | | - Gürkan Yiğittürk
- Ege University School of MedicineDepartment of Histology and EmbryologyIzmirTurkey
| | - Ayfer Meral
- Dumlupinar University School of MedicineDepartment of BiochemistryKütahyaTurkey
| | - Dilek Taskiran
- Ege University School of MedicineDepartment of PhysiologyIzmirTurkey
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21
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Parkinsonian features in aging GFAP.HMOX1 transgenic mice overexpressing human HO-1 in the astroglial compartment. Neurobiol Aging 2017; 58:163-179. [DOI: 10.1016/j.neurobiolaging.2017.06.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 06/05/2017] [Accepted: 06/20/2017] [Indexed: 11/21/2022]
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22
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Positive modulation of α5 GABA A receptors in preadolescence prevents reduced locomotor response to amphetamine in adult female but not male rats prenatally exposed to lipopolysaccharide. Int J Dev Neurosci 2017; 61:31-39. [PMID: 28610974 DOI: 10.1016/j.ijdevneu.2017.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/02/2017] [Accepted: 06/03/2017] [Indexed: 12/16/2022] Open
Abstract
We previously demonstrated that lipopolysaccharide (LPS) administered intraperitoneally (i.p.) to pregnant Wistar rat dams, at embryonic days 15 and 16 (E15/16), induced a decrease of baseline locomotor activity and diminished reactivity to amphetamine in adult female offspring. In the present study we aimed to assess the duration of LPS-induced maternal immune activation (MIA) and investigate possible changes in levels of main neurotransmitters in fetal brain during MIA. We hypothesized that the observed behavioral changes may be linked with MIA-induced disturbance of prenatal GABAergic system development, especially with α5 GABAA receptors (α5GABAARs), expression of which takes place between E14 and E17. Thereafter, we set to investigate if later potentiation of α5GABAARs in offspring's preadolescence (from postnatal day 22-28) could prevent the deficit in locomotor reactivity to amphetamine observed in adulthood, at postnatal day P60. The elevation of IL-6 in amniotic fluid 6h after LPS treatment (100μg/kg, i.p.) at E15 was concurrent with a significant increase of GABA and decrease of glutamate concentration in fetal brain. Moreover, repeated administration of MP-III-022, a selective positive allosteric modulator of α5GABAARs, at a dose (2mg/kg daily, i.p.) derived from a separate pharmacokinetic study, prevented the LPS-induced decrease in locomotor reactivity to amphetamine (0.5mg/kg, i.p.) in adult females. These results were not mirrored in the parallel set of experiments with male offspring from LPS-treated rats. The results suggest that pharmacological potentiation of α5GABAARs activity in preadolescence may ameliorate at least some of adverse consequences of exposure to MIA in utero.
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23
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Costa LG, Chang YC, Cole TB. Developmental Neurotoxicity of Traffic-Related Air Pollution: Focus on Autism. Curr Environ Health Rep 2017; 4:156-165. [PMID: 28417440 PMCID: PMC5952375 DOI: 10.1007/s40572-017-0135-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE OF REVIEW Epidemiological and animal studies suggest that air pollution may negatively affect the central nervous system (CNS) and contribute to CNS diseases. Traffic-related air pollution is a major contributor to global air pollution, and diesel exhaust (DE) is its most important component. RECENT FINDINGS Several studies suggest that young individuals may be particularly susceptible to air pollution-induced neurotoxicity and that perinatal exposure may cause or contribute to developmental disabilities and behavioral abnormalities. In particular, a number of recent studies have found associations between exposures to traffic-related air pollution and autism spectrum disorders (ASD), which are characterized by impairment in socialization and in communication and by the presence of repetitive and unusual behaviors. The cause(s) of ASD are unknown, and while it may have a hereditary component, environmental factors are increasingly suspected as playing a pivotal role in its etiology, particularly in genetically susceptible individuals. Autistic children present higher levels of neuroinflammation and systemic inflammation, which are also hallmarks of exposure to traffic-related air pollution. Gene-environment interactions may play a relevant role in determining individual susceptibility to air pollution developmental neurotoxicity. Given the worldwide presence of elevated air pollution, studies on its effects and mechanisms on the developing brain, genetic susceptibility, role in neurodevelopmental disorders, and possible therapeutic interventions are certainly warranted.
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Affiliation(s)
- Lucio G Costa
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA.
- Department of Neuroscience, University of Parma, Parma, Italy.
| | - Yu-Chi Chang
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA
| | - Toby B Cole
- Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA
- Center on Human Development and Disability, University of Washington, Seattle, WA, USA
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24
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Lim JS, Lim MY, Choi Y, Ko G. Modeling environmental risk factors of autism in mice induces IBD-related gut microbial dysbiosis and hyperserotonemia. Mol Brain 2017; 10:14. [PMID: 28427452 PMCID: PMC5399341 DOI: 10.1186/s13041-017-0292-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 04/04/2017] [Indexed: 02/07/2023] Open
Abstract
Autism spectrum disorder (ASD) is a range of neurodevelopmental conditions that are sharply increasing in prevalence worldwide. Intriguingly, ASD is often accompanied by an array of systemic aberrations including (1) increased serotonin, (2) various modes of gastrointestinal disorders, and (3) inflammatory bowel disease (IBD), albeit the underlying cause for such comorbidities remains uncertain. Also, accumulating number of studies report that the gut microbial composition is significantly altered in children with ASD or patients with IBD. Surprisingly, when we analyzed the gut microbiota of poly I:C and VPA-induced mouse models of ASD, we found a distinct pattern of microbial dysbiosis that highly recapitulated those reported in clinical cases of ASD and IBD. Moreover, we report that such microbial dysbiosis led to notable perturbations in microbial metabolic pathways that are known to negatively affect the host, especially with regards to the pathogenesis of ASD and IBD. Lastly, we found that serum level of serotonin is significantly increased in both poly I:C and VPA mice, and that it correlates with increases of a bacterial genus and a metabolic pathway that are implicated in stimulation of host serotonin production. Our results using animal model identify prenatal environmental risk factors of autism as possible causative agents of IBD-related gut microbial dysbiosis in ASD, and suggest a multifaceted role of gut microbiota in the systemic pathogenesis of ASD and hyperserotonemia.
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Affiliation(s)
- Joon Seo Lim
- Department of Environmental Health Sciences, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea.,Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea
| | - Mi Young Lim
- Department of Environmental Health Sciences, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea.,Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea.,Research Group of Gut Microbiome, Korea Food Research Institute, Seongnam, Gyeonggi-do, Republic of Korea
| | - Yongbin Choi
- Department of Environmental Health Sciences, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea
| | - GwangPyo Ko
- Department of Environmental Health Sciences, Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea. .,Center for Human and Environmental Microbiome, Seoul National University, Seoul, Republic of Korea. .,N-Bio, Seoul National University, Seoul, Republic of Korea. .,KoBioLabs, Inc., 1-Gwanak-ro, Gwanak-gu, Bldg 220, Rm 630, Seoul, 151-746, Republic of Korea.
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25
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Guo JN, Tian LY, Liu WY, Mu J, Zhou D. Activation of the Akt/mTOR signaling pathway: A potential response to long-term neuronal loss in the hippocampus after sepsis. Neural Regen Res 2017; 12:1832-1842. [PMID: 29239329 PMCID: PMC5745837 DOI: 10.4103/1673-5374.219044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Survivors of sepsis may suffer chronic cognitive impairment as a long-term sequela. However, the precise mechanisms of cognitive dysfunction after sepsis are not well understood. We employed the cecal ligation-and-puncture-induced septic mouse model. We observed elevated phosphorylation of Akt, mammalian target of rapamycin (mTOR) and p70S6K on days 14 and 60, progressive neuronal loss in the cornu ammonis 1 region, and abnormal neuronal morphology in the hippocampus in the sepsis mouse model. These findings indicate that changes in neuronal morphology and number in the hippocampus after sepsis were associated with strong activation of the Akt/mTOR signaling pathway, and may reflect a "self-rescuing" feedback response to neuronal loss after sepsis.
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Affiliation(s)
- Jia-Nan Guo
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Lin-Yu Tian
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Wen-Yu Liu
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Jie Mu
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Dong Zhou
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
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Neuroinflammation in Autism: Plausible Role of Maternal Inflammation, Dietary Omega 3, and Microbiota. Neural Plast 2016; 2016:3597209. [PMID: 27840741 PMCID: PMC5093279 DOI: 10.1155/2016/3597209] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/24/2016] [Accepted: 09/27/2016] [Indexed: 02/06/2023] Open
Abstract
Several genetic causes of autism spectrum disorder (ASD) have been identified. However, more recent work has highlighted that certain environmental exposures early in life may also account for some cases of autism. Environmental insults during pregnancy, such as infection or malnutrition, seem to dramatically impact brain development. Maternal viral or bacterial infections have been characterized as disruptors of brain shaping, even if their underlying mechanisms are not yet fully understood. Poor nutritional diversity, as well as nutrient deficiency, is strongly associated with neurodevelopmental disorders in children. For instance, imbalanced levels of essential fatty acids, and especially polyunsaturated fatty acids (PUFAs), are observed in patients with ASD and other neurodevelopmental disorders (e.g., attention deficit hyperactivity disorder (ADHD) and schizophrenia). Interestingly, PUFAs, and specifically n-3 PUFAs, are powerful immunomodulators that exert anti-inflammatory properties. These prenatal dietary and immunologic factors not only impact the fetal brain, but also affect the microbiota. Recent work suggests that the microbiota could be the missing link between environmental insults in prenatal life and future neurodevelopmental disorders. As both nutrition and inflammation can massively affect the microbiota, we discuss here how understanding the crosstalk between these three actors could provide a promising framework to better elucidate ASD etiology.
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Crowley T, Cryan JF, Downer EJ, O'Leary OF. Inhibiting neuroinflammation: The role and therapeutic potential of GABA in neuro-immune interactions. Brain Behav Immun 2016; 54:260-277. [PMID: 26851553 DOI: 10.1016/j.bbi.2016.02.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 01/22/2016] [Accepted: 02/02/2016] [Indexed: 12/25/2022] Open
Abstract
The central nervous system, once thought to be a site of immunological privilege, has since been found to harbour immunocompetent cells and to communicate with the peripheral nervous system. In the central nervous system (CNS), glial cells display immunological responses to pathological and physiological stimuli through pro- and anti-inflammatory cytokine and chemokine signalling, antigen presentation and the clearing of cellular debris through phagocytosis. While this neuroinflammatory signalling can act to reduce neuronal damage and comprises a key facet of CNS homeostasis, persistent inflammation or auto-antigen-mediated immunoreactivity can induce a positive feedback cycle of neuroinflammation that ultimately results in necrosis of glia and neurons. Persistent neuroinflammation has been recognised as a major pathological component of virtually all neurodegenerative diseases and has also been a focus of research into the pathology underlying psychiatric disorders. Thus, pharmacological strategies to curb the pathological effects of persistent neuroinflammation are of interest for many disorders of the CNS. Accumulating evidence suggests that GABAergic activities are closely bound to immune processes and signals, and thus the GABAergic neurotransmitter system might represent an important therapeutic target in modulating neuroinflammation. Here, we review evidence that inflammation induces changes in the GABA neurotransmitter system in the CNS and that GABAergic signalling exerts a reciprocal influence over neuroinflammatory processes. Together, the data support the hypothesis that the GABA system is a potential therapeutic target in the modulation of central inflammation.
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Affiliation(s)
- Tadhg Crowley
- Department of Anatomy and Neuroscience, University College Cork, Ireland
| | - John F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Ireland; APC Microbiome Institute, University College Cork, Ireland
| | - Eric J Downer
- School of Medicine, Discipline of Physiology, Trinity Biomedical Sciences Institute, Trinity College, Dublin 2, Ireland.
| | - Olivia F O'Leary
- Department of Anatomy and Neuroscience, University College Cork, Ireland; APC Microbiome Institute, University College Cork, Ireland.
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28
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Lintas C, Sacco R, Persico AM. Differential methylation at the RELN gene promoter in temporal cortex from autistic and typically developing post-puberal subjects. J Neurodev Disord 2016; 8:18. [PMID: 27134686 PMCID: PMC4850686 DOI: 10.1186/s11689-016-9151-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 04/12/2016] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Reelin plays a pivotal role in neurodevelopment and in post-natal synaptic plasticity and has been implicated in the pathogenesis of autism spectrum disorder (ASD). The reelin (RELN) gene expression is significantly decreased in ASD, both in the brain and peripherally. Methylation at the RELN gene promoter is largely triggered at puberty, and hypermethylation has been found in post-mortem brains of schizophrenic and bipolar patients. METHODS In this study, we assessed RELN gene methylation status in post-mortem temporocortical tissue samples (BA41/42 or 22) of six pairs of post-puberal individuals with ASD and typically developing subjects, matched for sex (male:female, M:F = 5:1), age, and post-mortem interval. RESULTS ASD patients display a significantly higher number of methylated CpG islands and heavier methylation in the 5' region of the RELN gene promoter, spanning from -458 to -223 bp, whereas controls have more methylated CpG positions and greater extent of methylation at the 3' promoter region, spanning from -222 to +1 bp. The most upstream promoter region (-458 to -364 bp) is methylated only in ASD brains, while the most downstream region (-131 to +1 bp) is methylated exclusively in control brains. Within this general framework, three different methylation patterns are discernible, each correlated with different extents of reduction in reelin gene expression among ASD individuals compared to controls. CONCLUSIONS The methylation pattern is different in ASD and control post-mortem brains. ASD-specific CpG positions, located in the most upstream gene promoter region, may exert a functional role potentially conferring ASD risk by blunting RELN gene expression.
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Affiliation(s)
- Carla Lintas
- Unit of Child and Adolescent Neuropsychiatry, University Campus Bio-Medico, Rome, Italy ; Laboratory of Molecular Psychiatry and Neurogenetics, University Campus Bio-Medico, Rome, Italy
| | - Roberto Sacco
- Unit of Child and Adolescent Neuropsychiatry, University Campus Bio-Medico, Rome, Italy ; Laboratory of Molecular Psychiatry and Neurogenetics, University Campus Bio-Medico, Rome, Italy
| | - Antonio M Persico
- Unit of Child and Adolescent Neuropsychiatry, "Gaetano Martino" University Hospital, University of Messina, via Consolare Valeria 1, I-98125 Messina, Italy ; Mafalda Luce Center for Pervasive Developmental Disorders, Milan, Italy
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Giovanoli S, Notter T, Richetto J, Labouesse MA, Vuillermot S, Riva MA, Meyer U. Late prenatal immune activation causes hippocampal deficits in the absence of persistent inflammation across aging. J Neuroinflammation 2015; 12:221. [PMID: 26602365 PMCID: PMC4659211 DOI: 10.1186/s12974-015-0437-y] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/16/2015] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Prenatal exposure to infection and/or inflammation is increasingly recognized to play an important role in neurodevelopmental brain disorders. It has recently been postulated that prenatal immune activation, especially when occurring during late gestational stages, may also induce pathological brain aging via sustained effects on systemic and central inflammation. Here, we tested this hypothesis using an established mouse model of exposure to viral-like immune activation in late pregnancy. METHODS Pregnant C57BL6/J mice on gestation day 17 were treated with the viral mimetic polyriboinosinic-polyribocytidilic acid (poly(I:C)) or control vehicle solution. The resulting offspring were first tested using cognitive and behavioral paradigms known to be sensitive to hippocampal damage, after which they were assigned to quantitative analyses of inflammatory cytokines, microglia density and morphology, astrocyte density, presynaptic markers, and neurotrophin expression in the hippocampus throughout aging (1, 5, and 22 months of age). RESULTS Maternal poly(I:C) treatment led to a robust increase in inflammatory cytokine levels in late gestation but did not cause persistent systemic or hippocampal inflammation in the offspring. The late prenatal manipulation also failed to cause long-term changes in microglia density, morphology, or activation, and did not induce signs of astrogliosis in pubescent, adult, or aged offspring. Despite the lack of persistent inflammatory or glial anomalies, offspring of poly(I:C)-exposed mothers showed marked and partly age-dependent deficits in hippocampus-regulated cognitive functions as well as impaired hippocampal synaptophysin and brain-derived neurotrophic factor (BDNF) expression. CONCLUSIONS Late prenatal exposure to viral-like immune activation in mice causes hippocampus-related cognitive and synaptic deficits in the absence of chronic inflammation across aging. These findings do not support the hypothesis that this form of prenatal immune activation may induce pathological brain aging via sustained effects on systemic and central inflammation. We further conclude that poly(I:C)-based prenatal immune activation models are reliable in their effectiveness to induce (hippocampal) neuropathology across aging, but they appear unsuited for studying the role of chronic systemic or central inflammation in brain aging.
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Affiliation(s)
- Sandra Giovanoli
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | - Tina Notter
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Winterthurerstrasse 260, 8057, Zurich, Switzerland
| | - Juliet Richetto
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Winterthurerstrasse 260, 8057, Zurich, Switzerland
| | - Marie A Labouesse
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland
| | | | - Marco A Riva
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
- Center of Excellence on Neurodegenerative Diseases, Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Urs Meyer
- Physiology and Behavior Laboratory, ETH Zurich, Schwerzenbach, Switzerland.
- Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Winterthurerstrasse 260, 8057, Zurich, Switzerland.
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30
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Labouesse MA, Langhans W, Meyer U. Abnormal context-reward associations in an immune-mediated neurodevelopmental mouse model with relevance to schizophrenia. Transl Psychiatry 2015; 5:e637. [PMID: 26371765 PMCID: PMC5068811 DOI: 10.1038/tp.2015.129] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 06/24/2015] [Accepted: 07/22/2015] [Indexed: 12/19/2022] Open
Abstract
Impairments in central reward processing constitute an important aspect of the negative symptoms of schizophrenia. Despite its clinical relevance, the etiology of deficient reward processing in schizophrenia remains largely unknown. Here, we used an epidemiologically informed mouse model of schizophrenia to explore the effects of prenatal immune activation on reward-related functions. The model is based on maternal administration of the viral mimic PolyI:C and has been developed in relation to the epidemiological evidence demonstrating enhanced risk of schizophrenia and related disorders following prenatal maternal infection. We show that prenatal immune activation induces selective deficits in the expression (but not acquisition) of conditioned place preference for a natural reward (sucrose) without changing hedonic or neophobic responses to the reward. On the other hand, prenatal immune activation led to enhanced place preference for the psychostimulant drug cocaine, while it attenuated the locomotor reaction to the drug. The prenatal exposure did not alter negative reinforcement learning as assessed using a contextual fear conditioning paradigm. Our findings suggest that the nature of reward-related abnormalities following prenatal immune challenge depends on the specificity of the reward (natural reward vs drug of abuse) as well as on the valence domain (positive vs negative reinforcement learning). Moreover, our data indicate that reward abnormalities emerging in prenatally immune-challenged offspring may, at least in part, stem from an inability to retrieve previously established context-reward associations and to integrate such information for appropriate goal-directed behavior.
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Affiliation(s)
- M A Labouesse
- Department of Health Sciences and Technology, Physiology and Behavior Laboratory, Swiss Federal Institute of Technology (ETH) Zurich, Schwerzenbach, Switzerland,Physiology and Behavior Laboratory, Swiss Federal Institute of Technology (ETH), Zurich, Schorenstrasse 16, 8603 Schwerzenbach, Switzerland. E-mail:
| | - W Langhans
- Department of Health Sciences and Technology, Physiology and Behavior Laboratory, Swiss Federal Institute of Technology (ETH) Zurich, Schwerzenbach, Switzerland
| | - U Meyer
- Department of Health Sciences and Technology, Physiology and Behavior Laboratory, Swiss Federal Institute of Technology (ETH) Zurich, Schwerzenbach, Switzerland,Institute of Pharmacology and Toxicology, University of Zurich-Vetsuisse, Zurich, Switzerland
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Möller M, Swanepoel T, Harvey BH. Neurodevelopmental Animal Models Reveal the Convergent Role of Neurotransmitter Systems, Inflammation, and Oxidative Stress as Biomarkers of Schizophrenia: Implications for Novel Drug Development. ACS Chem Neurosci 2015; 6:987-1016. [PMID: 25794269 DOI: 10.1021/cn5003368] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Schizophrenia is a life altering disease with a complex etiology and pathophysiology, and although antipsychotics are valuable in treating the disorder, certain symptoms and/or sufferers remain resistant to treatment. Our poor understanding of the underlying neuropathological mechanisms of schizophrenia hinders the discovery and development of improved pharmacological treatment, so that filling these gaps is of utmost importance for an improved outcome. A vast amount of clinical data has strongly implicated the role of inflammation and oxidative insults in the pathophysiology of schizophrenia. Preclinical studies using animal models are fundamental in our understanding of disease development and pathology as well as the discovery and development of novel treatment options. In particular, social isolation rearing (SIR) and pre- or postnatal inflammation (PPNI) have shown great promise in mimicking the biobehavioral manifestations of schizophrenia. Furthermore, the "dual-hit" hypothesis of schizophrenia states that a first adverse event such as genetic predisposition or a prenatal insult renders an individual susceptible to develop the disease, while a second insult (e.g., postnatal inflammation, environmental adversity, or drug abuse) may be necessary to precipitate the full-blown syndrome. Animal models that emphasize the "dual-hit" hypothesis therefore provide valuable insight into understanding disease progression. In this Review, we will discuss SIR, PPNI, as well as possible "dual-hit" animal models within the context of the redox-immune-inflammatory hypothesis of schizophrenia, correlating such changes with the recognized monoamine and behavioral alterations of schizophrenia. Finally, based on these models, we will review new therapeutic options, especially those targeting immune-inflammatory and redox pathways.
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Affiliation(s)
- M. Möller
- Department of Pharmacology and ‡Center of Excellence for Pharmaceutical Sciences,
School of Pharmacy, North-West University, Potchefstroom 2531, South Africa
| | - T. Swanepoel
- Department of Pharmacology and ‡Center of Excellence for Pharmaceutical Sciences,
School of Pharmacy, North-West University, Potchefstroom 2531, South Africa
| | - B. H. Harvey
- Department of Pharmacology and ‡Center of Excellence for Pharmaceutical Sciences,
School of Pharmacy, North-West University, Potchefstroom 2531, South Africa
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Fang SY, Wang S, Huang N, Yeh HH, Chen CY. Prenatal Infection and Autism Spectrum Disorders in Childhood: A Population-Based Case-Control Study in Taiwan. Paediatr Perinat Epidemiol 2015; 29:307-16. [PMID: 25989831 DOI: 10.1111/ppe.12194] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Infection in pregnancy has long been linked with negative postnatal development and health. This study aims to assess the association between prenatal infections and autism spectrum disorders (ASDs) across three trimesters and to probe possible sex heterogeneity in such link. METHOD A total of 4184 children with incident ASDs and 16,734 matched children were identified from the 2000-2007 National Health Insurance Research Database. For each child, information pertaining to the mother's infection during pregnancy, sociodemographics, and medical history was retrieved from healthcare records. Conditional logistic analyses were carried out to estimate the strength of associations with adjustment for multiple comparisons. RESULT Pooled analyses demonstrated that having two or more outpatient visits for genital infection [adjusted odds ratio (aOR): 1.34; 95% confidence interval (95% CI) 1.12, 1.60; false discovery rate (FDR) < 0.01] and bacterial infection (aOR: 1.24; 95% CI 1.06, 1.43; FDR < 0.05) in the third trimester were slightly associated with increased risk of ASDs. No statistically significant sex differences were found. CONCLUSION The present study contributes updated population-based evidence about the connection between prenatal infection and ASDs. Potential effect of bacterial and genital tract infections during the third trimester on risk of ASDs warrants further exploration.
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Affiliation(s)
- Shao-You Fang
- Institute of Public Health, National Yang-Ming University, Taipei, Taiwan.,Center of Neuropsychiatric Research, National Health Research Institutes, Miaoli County, Taiwan
| | - Sabrina Wang
- Institute of Anatomy and Cell Biology, National Yang-Ming University, Taipei, Taiwan
| | - Nicole Huang
- Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
| | - Hsueh-Han Yeh
- Department of Epidemiology and Biostatistics, Michigan State University, MI
| | - Chuan-Yu Chen
- Institute of Public Health, National Yang-Ming University, Taipei, Taiwan.,Center of Neuropsychiatric Research, National Health Research Institutes, Miaoli County, Taiwan
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Loke YJ, Hannan AJ, Craig JM. The Role of Epigenetic Change in Autism Spectrum Disorders. Front Neurol 2015; 6:107. [PMID: 26074864 PMCID: PMC4443738 DOI: 10.3389/fneur.2015.00107] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/28/2015] [Indexed: 12/14/2022] Open
Abstract
Autism spectrum disorders (ASD) are a heterogeneous group of neurodevelopmental disorders characterized by problems with social communication, social interaction, and repetitive or restricted behaviors. ASD are comorbid with other disorders including attention deficit hyperactivity disorder, epilepsy, Rett syndrome, and Fragile X syndrome. Neither the genetic nor the environmental components have been characterized well enough to aid diagnosis or treatment of non-syndromic ASD. However, genome-wide association studies have amassed evidence suggesting involvement of hundreds of genes and a variety of associated genetic pathways. Recently, investigators have turned to epigenetics, a prime mediator of environmental effects on genomes and phenotype, to characterize changes in ASD that constitute a molecular level on top of DNA sequence. Though in their infancy, such studies have the potential to increase our understanding of the etiology of ASD and may assist in the development of biomarkers for its prediction, diagnosis, prognosis, and eventually in its prevention and intervention. This review focuses on the first few epigenome-wide association studies of ASD and discusses future directions.
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Affiliation(s)
- Yuk Jing Loke
- Murdoch Childrens Research Institute, Royal Children's Hospital and Department of Paediatrics, University of Melbourne , Parkville, VIC , Australia
| | - Anthony John Hannan
- Melbourne Brain Centre, Florey Institute of Neuroscience and Mental Health, The University of Melbourne , Parkville, VIC , Australia
| | - Jeffrey Mark Craig
- Murdoch Childrens Research Institute, Royal Children's Hospital and Department of Paediatrics, University of Melbourne , Parkville, VIC , Australia
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Wischhof L, Irrsack E, Osorio C, Koch M. Prenatal LPS-exposure--a neurodevelopmental rat model of schizophrenia--differentially affects cognitive functions, myelination and parvalbumin expression in male and female offspring. Prog Neuropsychopharmacol Biol Psychiatry 2015; 57:17-30. [PMID: 25455585 DOI: 10.1016/j.pnpbp.2014.10.004] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 10/08/2014] [Accepted: 10/10/2014] [Indexed: 01/15/2023]
Abstract
Maternal infection during pregnancy increases the risk for the offspring to develop schizophrenia. Gender differences can be seen in various features of the illness and sex steroid hormones (e.g. estrogen) have strongly been implicated in the disease pathology. In the present study, we evaluated sex differences in the effects of prenatal exposure to a bacterial endotoxin (lipopolysaccharide, LPS) in rats. Pregnant dams received LPS-injections (100 μg/kg) at gestational day 15 and 16. The offspring was then tested for prepulse inhibition (PPI), locomotor activity, anxiety-like behavior and object recognition memory at various developmental time points. At postnatal day (PD) 33 and 60, prenatally LPS-exposed rats showed locomotor hyperactivity which was similar in male and female offspring. Moreover, prenatal LPS-treatment caused PPI deficits in pubertal (PD45) and adult (PD90) males while PPI impairments were found only at PD45 in prenatally LPS-treated females. Following prenatal LPS-administration, recognition memory for objects was impaired in both sexes with males being more severely affected. Additionally, we assessed prenatal infection-induced alterations of parvalbumin (Parv) expression and myelin fiber density. Male offspring born to LPS-challenged mothers showed decreased myelination in cortical and limbic brain regions as well as reduced numbers of Parv-expressing cells in the medial prefrontal cortex (mPFC), hippocampus and entorhinal cortex. In contrast, LPS-exposed female rats showed only a modest decrease in myelination and Parv immunoreactivity. Collectively, our data indicate that some of the prenatal immune activation effects are sex dependent and further strengthen the importance of taking into account gender differences in animal models of schizophrenia.
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Affiliation(s)
- Lena Wischhof
- Brain Research Institute, Department of Neuropharmacology, University of Bremen, Hochschulring 18, 28359 Bremen, Germany.
| | - Ellen Irrsack
- Brain Research Institute, Department of Neuropharmacology, University of Bremen, Hochschulring 18, 28359 Bremen, Germany
| | - Carmen Osorio
- Brain Research Institute, Department of Neuropharmacology, University of Bremen, Hochschulring 18, 28359 Bremen, Germany
| | - Michael Koch
- Brain Research Institute, Department of Neuropharmacology, University of Bremen, Hochschulring 18, 28359 Bremen, Germany
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35
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Prenatal administration of lipopolysaccharide induces sex-dependent changes in glutamic acid decarboxylase and parvalbumin in the adult rat brain. Neuroscience 2015; 287:78-92. [DOI: 10.1016/j.neuroscience.2014.12.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 12/02/2014] [Accepted: 12/09/2014] [Indexed: 11/19/2022]
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36
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Solati J, Kleehaupt E, Kratz O, Moll GH, Golub Y. Inverse effects of lipopolysaccharides on anxiety in pregnant mice and their offspring. Physiol Behav 2014; 139:369-74. [PMID: 25447752 DOI: 10.1016/j.physbeh.2014.10.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 10/14/2014] [Indexed: 11/29/2022]
Abstract
This study aimed to evaluate the effects of the bacterial lipopolysaccharide (LPS) exposure during early pregnancy on anxiety-related behaviour of both pregnant female mice and their male offspring. Pregnant NMRI mice were treated with subcutaneous injections of LPS (30, 60, 120, 240 and 480 μg/kg) on the tenth gestational day of pregnancy. Pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-6 and corticosterone levels, were measured in maternal serum 1.5h following the LPS injections. Baseline anxiety levels of pregnant mice (1.5h after LPS administration) and their male offspring (at postnatal days 60-70) were investigated with the elevated plus maze (EPM) test. In addition, anxiety levels in the offspring were measured after 2h restraint stress or TNF-α (10 μg/kg) administration. Our results demonstrate that LPS administration induces anxiety-like behaviour and a significant increase in cytokines and corticosterone levels in maternal serum. However, in male offspring, prenatal LPS administration has no significant effects on serum cytokines and corticosterone secretion with an exception of the lowest LPS dose that slightly reduced corticosterone levels. Interestingly, prenatal LPS treatment seemed to decrease the baseline anxiety levels, while pretreatment with restraint stress or TNF-α abolished this anxiolytic effects. In summary, our results suggest that prenatal exposure to LPS during early pregnancy may result in reduced baseline anxiety in adult male offspring.
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Affiliation(s)
- Jalal Solati
- Department of Child and Adolescent Mental Health, University of Erlangen-Nürnberg, Erlangen, Germany; Department of Biology, College of Science, Karaj branch, Islamic Azad University, Alborz, Iran
| | - Eva Kleehaupt
- Department of Child and Adolescent Mental Health, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver Kratz
- Department of Child and Adolescent Mental Health, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Gunther H Moll
- Department of Child and Adolescent Mental Health, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Yulia Golub
- Department of Child and Adolescent Mental Health, University of Erlangen-Nürnberg, Erlangen, Germany.
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37
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Maternal immune activation and abnormal brain development across CNS disorders. Nat Rev Neurol 2014; 10:643-60. [PMID: 25311587 DOI: 10.1038/nrneurol.2014.187] [Citation(s) in RCA: 604] [Impact Index Per Article: 60.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Epidemiological studies have shown a clear association between maternal infection and schizophrenia or autism in the progeny. Animal models have revealed maternal immune activation (mIA) to be a profound risk factor for neurochemical and behavioural abnormalities in the offspring. Microglial priming has been proposed as a major consequence of mIA, and represents a critical link in a causal chain that leads to the wide spectrum of neuronal dysfunctions and behavioural phenotypes observed in the juvenile, adult or aged offspring. Such diversity of phenotypic outcomes in the mIA model are mirrored by recent clinical evidence suggesting that infectious exposure during pregnancy is also associated with epilepsy and, to a lesser extent, cerebral palsy in children. Preclinical research also suggests that mIA might precipitate the development of Alzheimer and Parkinson diseases. Here, we summarize and critically review the emerging evidence that mIA is a shared environmental risk factor across CNS disorders that varies as a function of interactions between genetic and additional environmental factors. We also review ongoing clinical trials targeting immune pathways affected by mIA that may play a part in disease manifestation. In addition, future directions and outstanding questions are discussed, including potential symptomatic, disease-modifying and preventive treatment strategies.
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38
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Foley KA, MacFabe DF, Kavaliers M, Ossenkopp KP. Sexually dimorphic effects of prenatal exposure to lipopolysaccharide, and prenatal and postnatal exposure to propionic acid, on acoustic startle response and prepulse inhibition in adolescent rats: relevance to autism spectrum disorders. Behav Brain Res 2014; 278:244-56. [PMID: 25300465 DOI: 10.1016/j.bbr.2014.09.032] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 09/16/2014] [Accepted: 09/20/2014] [Indexed: 02/07/2023]
Abstract
Potential environmental risk factors for autism spectrum disorders (ASD) include viral/bacterial infection and an altered microbiome composition. The present study investigated whether administration of immune and gastrointestinal factors during gestation and early life altered startle response and prepulse inhibition in adolescent offspring using lipopolysaccharide (LPS), a bacterial mimetic, and propionic acid (PPA), a short chain fatty acid and metabolic product of antibiotic resistant enteric bacteria. Pregnant Long-Evans rats were injected once a day with PPA (500 mg/kg SC) on G12-16, LPS (50 μg/kg SC) on G15 and G16, or vehicle control on G12-16 or G15-16. Male and female offspring were injected with PPA (500 mg/kg SC) or vehicle twice a day, every second day from postnatal days 10-18. Acoustic startle and prepulse inhibition was measured on postnatal days 45, 47, 49, and 51. Prenatal and postnatal treatments altered startle behavior in a sex-specific manner. Prenatal LPS treatment produced hyper-sensitivity to acoustic startle in males, but not females and did not alter prepulse inhibition. Subtle alterations in startle responses that disappeared with repeated trials occurred with prenatal PPA and postnatal PPA treatment in both male and female offspring. Prenatal PPA treatment decreased prepulse inhibition in females, but not males. Lastly, females receiving a double hit of PPA, prenatal and postnatal, showed sensitization to acoustic startle, providing evidence for the double hit hypothesis. The current study supports the hypotheses that immune activation and metabolic products of enteric bacteria may alter development and behavior in ways that resemble sensory abnormalities observed in ASD.
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Affiliation(s)
- Kelly A Foley
- Graduate Program in Neuroscience, Department of Psychology, University of Western Ontario, London, ON, Canada; The Kilee Patchell-Evans Autism Research Group, Department of Psychology, University of Western Ontario, London, ON, Canada
| | - Derrick F MacFabe
- The Kilee Patchell-Evans Autism Research Group, Department of Psychology and Psychiatry, Division of Developmental Disabilities, University of Western Ontario, London, ON, Canada
| | - Martin Kavaliers
- Graduate Program in Neuroscience, Department of Psychology, University of Western Ontario, London, ON, Canada; The Kilee Patchell-Evans Autism Research Group, Department of Psychology, University of Western Ontario, London, ON, Canada
| | - Klaus-Peter Ossenkopp
- Graduate Program in Neuroscience, Department of Psychology, University of Western Ontario, London, ON, Canada; The Kilee Patchell-Evans Autism Research Group, Department of Psychology, University of Western Ontario, London, ON, Canada.
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Rideau Batista Novais A, Crouzin N, Cavalier M, Boubal M, Guiramand J, Cohen-Solal C, de Jesus Ferreira MC, Cambonie G, Vignes M, Barbanel G. Tiagabine improves hippocampal long-term depression in rat pups subjected to prenatal inflammation. PLoS One 2014; 9:e106302. [PMID: 25184226 PMCID: PMC4153642 DOI: 10.1371/journal.pone.0106302] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 08/03/2014] [Indexed: 02/02/2023] Open
Abstract
Maternal inflammation during pregnancy is associated with the later development of cognitive and behavioral impairment in the offspring, reminiscent of the traits of schizophrenia or autism spectrum disorders. Hippocampal long-term potentiation and long-term depression of glutamatergic synapses are respectively involved in memory formation and consolidation. In male rats, maternal inflammation with lipopolysaccharide (LPS) led to a premature loss of long-term depression, occurring between 12 and 25 postnatal days instead of after the first postnatal month, and aberrant occurrence of long-term potentiation. We hypothesized this would be related to GABAergic system impairment. Sprague Dawley rats received either LPS or isotonic saline ip on gestational day 19. Male offspring's hippocampus was studied between 12 and 25 postnatal days. Morphological and functional analyses demonstrated that prenatal LPS triggered a deficit of hippocampal GABAergic interneurons, associated with presynaptic GABAergic transmission deficiency in male offspring. Increasing ambient GABA by impairing GABA reuptake with tiagabine did not interact with the low frequency-induced long-term depression in control animals but fully prevented its impairment in male offspring of LPS-challenged dams. Tiagabine furthermore prevented the aberrant occurrence of paired-pulse triggered long-term potentiation in these rats. Deficiency in GABA seems to be central to the dysregulation of synaptic plasticity observed in juvenile in utero LPS-challenged rats. Modulating GABAergic tone may be a possible therapeutic strategy at this developmental stage.
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Affiliation(s)
- Aline Rideau Batista Novais
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
- Neonatal Intensive Care Unit, Montpellier University Hospital, Montpellier, France
| | - Nadine Crouzin
- Laboratory NICN-UMR7259 “Neurobiologie des Interactions Cellulaires et Neurophysiopathologie”, CNRS - Aix-Marseille University, Marseille, France
| | - Mélanie Cavalier
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
| | - Mathilde Boubal
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
- Neonatal Intensive Care Unit, Montpellier University Hospital, Montpellier, France
| | - Janique Guiramand
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
| | - Catherine Cohen-Solal
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
| | - Marie-Céleste de Jesus Ferreira
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
| | - Gilles Cambonie
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
- Neonatal Intensive Care Unit, Montpellier University Hospital, Montpellier, France
| | - Michel Vignes
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
| | - Gérard Barbanel
- Laboratory IBMM-UMR 5247 “Institut des Biomolécules Max Mousseron”, CNRS - Montpellier 1 University - Montpellier 2 University, Montpellier, France
- * E-mail:
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Single and combined effects of prenatal immune activation and peripubertal stress on parvalbumin and reelin expression in the hippocampal formation. Brain Behav Immun 2014; 40:48-54. [PMID: 24859043 DOI: 10.1016/j.bbi.2014.04.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 04/03/2014] [Accepted: 04/15/2014] [Indexed: 11/21/2022] Open
Abstract
Exposure to prenatal infection and traumatizing experiences in peripubertal life are two environmental risk factors for developmental neuropsychiatric disorders. Modeling the cumulative neuronal impact of these factors in a translational animal model has led to the recent identification of pathological interactions between these environmental adversities in the development of adult brain dysfunctions. The present study explored the consequences of combined prenatal immune challenge and peripubertal stress on discrete cellular abnormalities in the γ-aminobutyric acid (GABA) system of the hippocampus. Pregnant mice were treated with the viral mimetic poly(I:C) (=polyriboinosinic-polyribocytidilic acid) or control solution, and offspring born to poly(I:C)-exposed or control mothers were then left undisturbed or subjected to unpredictable sub-chronic stress during peripubertal development. Stereological estimations of parvalbumin-expressing cells revealed a significant reduction of these GABAergic interneurons in the ventral dentate gyrus of adult offspring exposed to combined immune activation and stress. Single exposure to either environmental factor was insufficient to cause similar neuropathology. We further found that peripubertal stress exerted opposite effects on reelin-immunoreactive cells in the dorsal cornu ammonis (CA) region of the hippocampus, with stress increasing and decreasing reelin expression in control offspring and prenatally immune challenged animals, respectively. The present data suggest that the combination of two environmental risk factors, which have each been implicated in the etiology of major neuropsychiatric disease, induces significant but restricted neuropathological effects on hippocampal GABAergic cell populations known to be affected in brain disorders with neurodevelopmental components.
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Foley KA, MacFabe DF, Vaz A, Ossenkopp KP, Kavaliers M. Sexually dimorphic effects of prenatal exposure to propionic acid and lipopolysaccharide on social behavior in neonatal, adolescent, and adult rats: implications for autism spectrum disorders. Int J Dev Neurosci 2014; 39:68-78. [PMID: 24747144 DOI: 10.1016/j.ijdevneu.2014.04.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 04/07/2014] [Accepted: 04/07/2014] [Indexed: 12/14/2022] Open
Abstract
Emerging evidence suggests that the gut microbiome plays an important role in immune functioning, behavioral regulation and neurodevelopment. Altered microbiome composition, including altered short chain fatty acids, and/or immune system dysfunction, may contribute to neurodevelopmental disorders such as autism spectrum disorders (ASD), with some children with ASD exhibiting both abnormal gut bacterial metabolite composition and immune system dysfunction. This study describes the effects of prenatal propionic acid (PPA), a short chain fatty acid and metabolic product of many antibiotic resistant enteric bacteria, and of prenatal lipopolysaccharide (LPS), a bacterial mimetic and microbiome component, on social behavior in male and female neonatal, adolescent and adult rats. Pregnant Long-Evans rats were injected once a day with either a low level of PPA (500 mg/kg SC) on gestation days G12-16, LPS (50 μg/kg SC) on G12, or vehicle control on G12 or G12-16. Sex- and age-specific, subtle effects on behavior were observed. Both male and female PPA treated pups were impaired in a test of their nest seeking response, suggesting impairment in olfactory-mediated neonatal social recognition. As well, adolescent males, born to PPA treated dams, approached a novel object more than control animals and showed increased levels of locomotor activity compared to prenatal PPA females. Prenatal LPS produced subtle impairments in social behavior in adult male and female rats. These findings raise the possibility that brief prenatal exposure to elevated levels of microbiome products, such as PPA or LPS, can subtly influence neonatal, adolescent and adult social behavior.
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Affiliation(s)
- Kelly A Foley
- Graduate Program in Neuroscience, The University of Western Ontario, London, ON N6A 5B7, Canada; Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada.
| | - Derrick F MacFabe
- Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada; The Kilee Patchell-Evans Autism Research Group, Departments of Psychology and Psychiatry, Division of Developmental Disabilities, The University of Western Ontario, London, ON N6A 5C2, Canada.
| | - Alisha Vaz
- Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada.
| | - Klaus-Peter Ossenkopp
- Graduate Program in Neuroscience, The University of Western Ontario, London, ON N6A 5B7, Canada; Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada; The Kilee Patchell-Evans Autism Research Group, Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada.
| | - Martin Kavaliers
- Graduate Program in Neuroscience, The University of Western Ontario, London, ON N6A 5B7, Canada; Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada; The Kilee Patchell-Evans Autism Research Group, Department of Psychology, The University of Western Ontario, London, ON N6A 5C2, Canada.
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Green HF, Nolan YM. Inflammation and the developing brain: Consequences for hippocampal neurogenesis and behavior. Neurosci Biobehav Rev 2014; 40:20-34. [DOI: 10.1016/j.neubiorev.2014.01.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 01/12/2014] [Accepted: 01/13/2014] [Indexed: 02/06/2023]
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The role of microbes and autoimmunity in the pathogenesis of neuropsychiatric illness. Curr Opin Rheumatol 2014; 25:488-795. [PMID: 23656715 DOI: 10.1097/bor.0b013e32836208de] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW To illustrate how microbes might participate in the pathogenesis of neuropsychiatric illness by triggering the production of autoantibodies that bind to brain targets. RECENT FINDINGS Some studies link exposure to infectious agents to development of brain disorders; others have identified autoantibodies in individuals with these conditions without finding evidence of pathogens. Neither line of work demonstrates consistent associations between a specific neuropsychiatric disease and a particular environmental trigger or immune marker. Growing evidence suggests that the microbiome conditions host immunity to microbes and xenobiotics, and regulates autoimmune responses that can affect the central nervous system (CNS). The presence of CNS receptors for cytokines and other immune molecules underscores the importance of brain-immune crosstalk in maintaining normal function. An increased prevalence of familial autoimmunity, exposure to pathogens prenatally and postnatally, and findings of antibrain antibodies is common in disorders as diverse as schizophrenia, obsessive-compulsive disorder and autism, and suggests that differences in exposure timing and genetic vulnerability toward autoimmunity are important determinants of neuropsychiatric outcomes. SUMMARY Microbes, both pathogenic and commensal, can induce autoantibodies that bind to brain and affect behavior in susceptible hosts. Interventions that correct the microbial balance or diminish autoantibody binding may be effective in diverse neuropsychiatric conditions mediated by autoimmunity.
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Foley KA, Ossenkopp KP, Kavaliers M, MacFabe DF. Pre- and neonatal exposure to lipopolysaccharide or the enteric metabolite, propionic acid, alters development and behavior in adolescent rats in a sexually dimorphic manner. PLoS One 2014; 9:e87072. [PMID: 24466331 PMCID: PMC3899377 DOI: 10.1371/journal.pone.0087072] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 12/22/2013] [Indexed: 02/08/2023] Open
Abstract
Alterations in the composition of the gut microbiome and/or immune system function may have a role in the development of autism spectrum disorders (ASD). The current study examined the effects of prenatal and early life administration of lipopolysaccharide (LPS), a bacterial mimetic, and the short chain fatty acid, propionic acid (PPA), a metabolic fermentation product of enteric bacteria, on developmental milestones, locomotor activity, and anxiety-like behavior in adolescent male and female offspring. Pregnant Long-Evans rats were subcutaneously injected once a day with PPA (500 mg/kg) on gestation days G12–16, LPS (50 µg/kg) on G15–16, or vehicle control on G12–16 or G15–16. Male and female offspring were injected with PPA (500 mg/kg) or vehicle twice a day, every second day from postnatal days (P) 10–18. Physical milestones and reflexes were monitored in early life with prenatal PPA and LPS inducing delays in eye opening. Locomotor activity and anxiety were assessed in adolescence (P40–42) in the elevated plus maze (EPM) and open-field. Prenatal and postnatal treatments altered behavior in a sex-specific manner. Prenatal PPA decreased time spent in the centre of the open-field in males and females while prenatal and postnatal PPA increased anxiety behavior on the EPM in female rats. Prenatal LPS did not significantly influence those behaviors. Evidence for the double hit hypothesis was seen as females receiving a double hit of PPA (prenatal and postnatal) displayed increased repetitive behavior in the open-field. These results provide evidence for the hypothesis that by-products of enteric bacteria metabolism such as PPA may contribute to ASD, altering development and behavior in adolescent rats similar to that observed in ASD and other neurodevelopmental disorders.
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Affiliation(s)
- Kelly A. Foley
- Graduate Program in Neuroscience, The University of Western Ontario, London, Ontario, Canada
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada
- * E-mail:
| | - Klaus-Peter Ossenkopp
- Graduate Program in Neuroscience, The University of Western Ontario, London, Ontario, Canada
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada
- The Kilee Patchell-Evans Autism Research Group, Department of Psychology, The University of Western Ontario, London, Ontario, Canada
| | - Martin Kavaliers
- Graduate Program in Neuroscience, The University of Western Ontario, London, Ontario, Canada
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada
- The Kilee Patchell-Evans Autism Research Group, Department of Psychology, The University of Western Ontario, London, Ontario, Canada
| | - Derrick F. MacFabe
- Department of Psychology, The University of Western Ontario, London, Ontario, Canada
- The Kilee Patchell-Evans Autism Research Group, Division of Developmental Disabilities, Departments of Psychology and Psychiatry, The University of Western Ontario, London, Ontario, Canada
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Pitkänen A, Ndode-Ekane XE, Łukasiuk K, Wilczynski GM, Dityatev A, Walker MC, Chabrol E, Dedeurwaerdere S, Vazquez N, Powell EM. Neural ECM and epilepsy. PROGRESS IN BRAIN RESEARCH 2014; 214:229-62. [DOI: 10.1016/b978-0-444-63486-3.00011-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Prenatal immune activation interacts with stress and corticosterone exposure later in life to modulate N-methyl-D-aspartate receptor synaptic function and plasticity. Int J Neuropsychopharmacol 2013; 16:1835-48. [PMID: 23552018 DOI: 10.1017/s1461145713000229] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Prenatal infection is an environmental risk factor for schizophrenia while later in life, stressful events have been associated with the onset and severity of psychosis. Recent findings on the impact of stress on the N-methyl-d-aspartate receptor (NMDAR), of which hypofunctioning is implicated in schizophrenia, suggest changes in stress-induced regulation of the glutamatergic system may be related to the pathogenesis of schizophrenia. Our study aimed to test whether prenatal immune activation could interact with stress at adolescence to alter NMDAR function. We used offspring from rat dams administered bacterial lipopolysaccharide (LPS) during pregnancy (gestational days 15 and 16), an animal model expressing schizophrenia-related behavioural phenotypes. Using electrophysiological techniques, we investigated effects of stress and the stress hormone corticosterone (Cort) on NMDAR-mediated synaptic function and long-term depression (LTD) in hippocampal CA1 slices from these adolescent (aged 28-39 d) male offspring. In prenatal LPS offspring, NMDAR-mediated synaptic function and LTD were reduced and abolished, respectively, compared to prenatal saline controls. Notably, in vivo stress and in vitro Cort treatment facilitated LTD in slices from prenatal LPS rats but not prenatal saline controls. Finally, Cort enhanced NMDAR-mediated synaptic function in slices from prenatal LPS rats only. We conclude that prenatal immune activation results in NMDAR hypofunction in the hippocampus of adolescent rats but also increases responsiveness of NMDAR-mediated synaptic function and LTD towards stress. Prenatal infection could confer susceptibility to schizophrenia through modification of hippocampal NMDAR function, with hypofunction in resting conditions and heightened responsiveness to stress, thus impacting the development of the disorder.
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Prenatal immune challenge in rats increases susceptibility to seizure-induced brain injury in adulthood. Brain Res 2013; 1519:78-86. [DOI: 10.1016/j.brainres.2013.04.047] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 04/23/2013] [Accepted: 04/23/2013] [Indexed: 01/22/2023]
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N-acetyl-cysteine prevents pyramidal cell disarray and reelin-immunoreactive neuron deficiency in CA3 after prenatal immune challenge in rats. Pediatr Res 2013; 73:750-5. [PMID: 23478644 DOI: 10.1038/pr.2013.40] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Prenatal infection is a major risk factor for the occurrence of neuropsychiatric disorders. These have been associated with hippocampal neuroanatomical and functional abnormalities. In the present study, we evaluated the occurrence of pyramidal cell disarray and reelin neuronal deficit in the hippocampus, and the protective role of N-acetyl-cysteine (NAC) in a rodent experimental model of prenatal immune challenge. METHODS Sprague-Dawley rats received either 500 μg/kg of endotoxin (lipopolysaccharide, LPS) or 2 ml/kg of isotonic saline by i.p. injection on day 19 of gestation. After LPS injection, rats were or were not maintained on a preventive treatment of NAC (5 g/l in tap water), up to delivery. The pyramidal cell orientation and the number and type of reelin-expressing neurons were determined in male offspring. RESULTS Prenatal LPS challenge led to permanent pyramidal cell disarray and to an early and transient decreased density of reelin-immunoreactive neurons. These disorders, more pronounced in the CA3 area, were prevented by NAC. CONCLUSION Hippocampal cytoarchitectural alterations and reelin deficiency may be involved in the development of remote cognitive impairments in this model. The antioxidant NAC is an efficient neuroprotective drug that underlines the role of oxidative stress in prenatal infection and associated neurodevelopmental damage.
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Folsom TD, Fatemi SH. The involvement of Reelin in neurodevelopmental disorders. Neuropharmacology 2013; 68:122-35. [PMID: 22981949 PMCID: PMC3632377 DOI: 10.1016/j.neuropharm.2012.08.015] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 08/14/2012] [Accepted: 08/16/2012] [Indexed: 12/21/2022]
Abstract
Reelin is a glycoprotein that serves important roles both during development (regulation of neuronal migration and brain lamination) and in adulthood (maintenance of synaptic function). A number of neuropsychiatric disorders including autism, schizophrenia, bipolar disorder, major depression, Alzheimer's disease and lissencephaly share a common feature of abnormal Reelin expression in the brain. Altered Reelin expression has been hypothesized to impair neuronal connectivity and synaptic plasticity, leading ultimately to the cognitive deficits present in these disorders. The mechanisms for abnormal Reelin expression in some of these disorders are currently unknown although possible explanations include early developmental insults, mutations, hypermethylation of the promoter for the Reelin gene (RELN), miRNA silencing of Reelin mRNA, FMRP underexpression and Reelin processing abnormalities. Increasing Reelin expression through pharmacological therapies may help ameliorate symptoms resulting from Reelin deficits. This article is part of the Special Issue entitled 'Neurodevelopmental Disorders'.
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Affiliation(s)
- Timothy D. Folsom
- Department of Psychiatry, Division of Neuroscience Research, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455, USA
| | - S. Hossein Fatemi
- Department of Psychiatry, Division of Neuroscience Research, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455, USA
- Department of Pharmacology, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455, USA
- Department of Neuroscience, University of Minnesota Medical School, 420 Delaware St SE, MMC 392, Minneapolis, MN 55455, USA
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Etiopathogenesis of autism spectrum disorders: fitting the pieces of the puzzle together. Med Hypotheses 2013; 81:26-35. [PMID: 23622947 DOI: 10.1016/j.mehy.2013.04.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 03/26/2013] [Accepted: 04/01/2013] [Indexed: 12/19/2022]
Abstract
Autism spectrum disorders (ASD) are disorders of the central nervous system characterized by impairments in communication and social reciprocity. Despite thousands of studies on this topic, the etiopathogenesis of these disorders remains unclear, apart from a general belief that they derive from an interaction between several genes and the environment. Given the mystery surrounding the etiopathogenesis of ASD it is impossible to plan effective preventive and treatment measures. This is of particular concern due to the progressive increase in the prevalence of ASD, which has reached a figure as high as 1:88 children in the USA. Here we present data corroborating a novel unifying hypothesis of the etiopathogenesis of ASD. We suggest that ASD are disorders of the immune system that occur in a very early phase of embryonic development. In a background of genetic predisposition and environmental predisposition (probably vitamin D deficiency), an infection (notably a viral infection) could trigger a deranged immune response which, in turn, results in damage to specific areas of the central nervous system. If proven, this hypothesis would have dramatic consequences for strategies aimed at preventing and treating ASD. To confirm or refute this hypothesis, we need a novel research approach, which unlike former approaches in this field, examine the major factors implicated in ASD (genetic, infections, vitamin D deficiency, immune system deregulation) not separately, but collectively and simultaneously.
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