1
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Chi OZ, Liu X, Fortus H, Werlen G, Jacinto E, Weiss HR. Inhibition of p70 Ribosomal S6 Kinase (S6K1) Reduces Cortical Blood Flow in a Rat Model of Autism-Tuberous Sclerosis. Neuromolecular Med 2024; 26:10. [PMID: 38570425 PMCID: PMC10990997 DOI: 10.1007/s12017-024-08780-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 03/04/2024] [Indexed: 04/05/2024]
Abstract
The manifestations of tuberous sclerosis complex (TSC) in humans include epilepsy, autism spectrum disorders (ASD) and intellectual disability. Previous studies suggested the linkage of TSC to altered cerebral blood flow and metabolic dysfunction. We previously reported a significant elevation in cerebral blood flow in an animal model of TSC and autism of young Eker rats. Inhibition of the mammalian target of rapamycin (mTOR) by rapamycin could restore normal oxygen consumption and cerebral blood flow. In this study, we investigated whether inhibiting a component of the mTOR signaling pathway, p70 ribosomal S6 kinase (S6K1), would yield comparable effects. Control Long Evans and Eker rats were divided into vehicle and PF-4708671 (S6K1 inhibitor, 75 mg/kg for 1 h) treated groups. Cerebral regional blood flow (14C-iodoantipyrine) was determined in isoflurane anesthetized rats. We found significantly increased basal cortical (+ 32%) and hippocampal (+ 15%) blood flow in the Eker rats. PF-4708671 significantly lowered regional blood flow in the cortex and hippocampus of the Eker rats. PF-4708671 did not significantly lower blood flow in these regions in the control Long Evans rats. Phosphorylation of S6-Ser240/244 and Akt-Ser473 was moderately decreased in Eker rats but only the latter reached statistical significance upon PF-4708671 treatment. Our findings suggest that moderate inhibition of S6K1 with PF-4708671 helps to restore normal cortical blood flow in Eker rats and that this information might have therapeutic potential in tuberous sclerosis complex and autism.
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Affiliation(s)
- Oak Z Chi
- Department of Anesthesiology and Perioperative Medicine, Rutgers Robert Wood Johnson Medical School, 125 Paterson Street, Suite 3100, New Brunswick, NJ, 08901-1977, USA.
| | - Xia Liu
- Department of Anesthesiology and Perioperative Medicine, Rutgers Robert Wood Johnson Medical School, 125 Paterson Street, Suite 3100, New Brunswick, NJ, 08901-1977, USA
| | - Harvey Fortus
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854, USA
| | - Guy Werlen
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854, USA
| | - Estela Jacinto
- Department of Biochemistry and Molecular Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854, USA
| | - Harvey R Weiss
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, 08854, USA
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2
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Pokorná M, Kútna V, Ovsepian SV, Matěj R, Černá M, O’Leary VB. Biomolecules to Biomarkers? U87MG Marker Evaluation on the Path towards Glioblastoma Multiforme Pathogenesis. Pharmaceutics 2024; 16:123. [PMID: 38258133 PMCID: PMC10818292 DOI: 10.3390/pharmaceutics16010123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024] Open
Abstract
The heterogeneity of the glioma subtype glioblastoma multiforme (GBM) challenges effective neuropathological treatment. The reliance on in vitro studies and xenografted animal models to simulate human GBM has proven ineffective. Currently, a dearth of knowledge exists regarding the applicability of cell line biomolecules to the realm of GBM pathogenesis. Our study's objectives were to address this preclinical issue and assess prominin-1, ICAM-1, PARTICLE and GAS5 as potential GBM diagnostic targets. The methodologies included haemoxylin and eosin staining, immunofluorescence, in situ hybridization and quantitative PCR. The findings identified that morphology correlates with malignancy in GBM patient pathology. Immunofluorescence confocal microscopy revealed prominin-1 in pseudo-palisades adjacent to necrotic foci in both animal and human GBM. Evidence is presented for an ICAM-1 association with degenerating vasculature. Significantly elevated nuclear PARTICLE expression from in situ hybridization and quantitative PCR reflected its role as a tumor activator. GAS5 identified within necrotic GBM validated this potential prognostic biomolecule with extended survival. Here we present evidence for the stem cell marker prominin-1 and the chemotherapeutic target ICAM-1 in a glioma animal model and GBM pathology sections from patients that elicited alternative responses to adjuvant chemotherapy. This foremost study introduces the long non-coding RNA PARTICLE into the context of human GBM pathogenesis while substantiating the role of GAS5 as a tumor suppressor. The validation of GBM biomarkers from cellular models contributes to the advancement towards superior detection, therapeutic responders and the ultimate attainment of promising prognoses for this currently incurable brain cancer.
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Affiliation(s)
- Markéta Pokorná
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Ruská 87, Vinohrady, 10000 Prague, Czech Republic; (M.P.); (M.Č.)
| | - Viera Kútna
- Department of Experimental Neurobiology, National Institute of Mental Health, Topolová 748, 25067 Klecany, Czech Republic;
| | - Saak V. Ovsepian
- Faculty of Engineering and Science, University of Greenwich London, Chatham Maritime, Kent ME4 4TB, UK;
| | - Radoslav Matěj
- Department of Pathology, Third Faculty of Medicine, Charles University, Ruská 87, Vinohrady, 10000 Prague, Czech Republic;
- Department of Pathology, University Hospital Královské Vinohrady, Šrobárova 50, Vinohrady, 10000 Prague, Czech Republic
| | - Marie Černá
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Ruská 87, Vinohrady, 10000 Prague, Czech Republic; (M.P.); (M.Č.)
| | - Valerie Bríd O’Leary
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Ruská 87, Vinohrady, 10000 Prague, Czech Republic; (M.P.); (M.Č.)
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3
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Elziny S, Crino PB. Vascularization in mTOR Mouse Mutants: An Effort Not in Vein. eNeuro 2023; 10:ENEURO.0122-23.2023. [PMID: 37479502 PMCID: PMC10368145 DOI: 10.1523/eneuro.0122-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 06/25/2023] [Indexed: 07/23/2023] Open
Abstract
Highlighted Research Paper: M. Dusing, C. L. LaSarge, A. White, L. G. Jerow, C. Gross and S. C. Danzer, "Neurovascular Development in Pten and Tsc2 Mouse Mutants."
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Affiliation(s)
- Soad Elziny
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, 21201 MD
| | - Peter B Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, 21201 MD
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4
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Dusing M, LaSarge CL, White A, Jerow LG, Gross C, Danzer SC. Neurovascular Development in Pten and Tsc2 Mouse Mutants. eNeuro 2023; 10:ENEURO.0340-22.2023. [PMID: 36759189 PMCID: PMC9953070 DOI: 10.1523/eneuro.0340-22.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Hyperactivation of the mechanistic target of rapamycin (mTOR) signaling pathway is linked to more than a dozen neurologic diseases, causing a range of pathologies, including excess neuronal growth, disrupted neuronal migration, cortical dysplasia, epilepsy and autism. The mTOR pathway also regulates angiogenesis. For the present study, therefore, we queried whether loss of Pten or Tsc2, both mTOR negative regulators, alters brain vasculature in three mouse models: one with Pten loss restricted to hippocampal dentate granule cells [DGC-Pten knock-outs (KOs)], a second with widespread Pten loss from excitatory forebrain neurons (FB-Pten KOs) and a third with focal loss of Tsc2 from cortical excitatory neurons (f-Tsc2 KOs). Total hippocampal vessel length and volume per dentate gyrus were dramatically increased in DGC-Pten knock-outs. DGC-Pten knock-outs had larger dentate gyri overall, however, and when normalized to these larger structures, vessel density was preserved. In addition, tests of blood-brain barrier integrity did not reveal increased permeability. FB-Pten KOs recapitulated the findings in the more restricted DGC-Pten KOs, with increased vessel area, but preserved vessel density. FB-Pten KOs did, however, exhibit elevated levels of the angiogenic factor VegfA. In contrast to findings with Pten, focal loss of Tsc2 from cortical excitatory neurons produced a localized increase in vessel density. Together, these studies demonstrate that hypervascularization is not a consistent feature of mTOR hyperactivation models and suggest that loss of different mTOR pathway regulatory genes exert distinct effects on angiogenesis.
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Affiliation(s)
- Mary Dusing
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
| | - Candi L LaSarge
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
- Departments of Anesthesia and Pediatrics, University of Cincinnati, Cincinnati, OH 45229
- Center for Pediatric Neuroscience, Cincinnati Children's Hospital, Cincinnati, OH 45229
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH 45219
| | - Angela White
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
| | - Lilian G Jerow
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH 45219
| | - Christina Gross
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
- Departments of Anesthesia and Pediatrics, University of Cincinnati, Cincinnati, OH 45229
- Center for Pediatric Neuroscience, Cincinnati Children's Hospital, Cincinnati, OH 45229
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH 45219
| | - Steve C Danzer
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
- Departments of Anesthesia and Pediatrics, University of Cincinnati, Cincinnati, OH 45229
- Center for Pediatric Neuroscience, Cincinnati Children's Hospital, Cincinnati, OH 45229
- Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH 45219
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5
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Granak S, Tuckova K, Kutna V, Vojtechova I, Bajkova L, Petrasek T, Ovsepian SV. Developmental effects of constitutive mTORC1 hyperactivity and environmental enrichment on structural synaptic plasticity and behaviour in a rat model of autism spectrum disorder. Eur J Neurosci 2023; 57:17-31. [PMID: 36380588 DOI: 10.1111/ejn.15864] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 09/18/2022] [Accepted: 11/09/2022] [Indexed: 11/17/2022]
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental condition causing a range of social and communication impairments. Although the role of multiple genes and environmental factors has been reported, the effects of the interplay between genes and environment on the onset and progression of the disease remains elusive. We housed wild-type (Tsc2+/+) and tuberous sclerosis 2 deficient (Tsc2+/-) Eker rats (ASD model) in individually ventilated cages or enriched conditions and conducted a series of behavioural tests followed by the histochemical analysis of dendritic spines and plasticity in three age groups (days 45, 90 and 365). The elevated plus-maze test revealed a reduction of anxiety by enrichment, whereas the mobility of young and adult Eker rats in the open field was lower compared to the wild type. In the social interaction test, an enriched environment reduced social contact in the youngest group and increased anogenital exploration in 90- and 365-day-old rats. Self-grooming was increased by environmental enrichment in young and adult rats and decreased in aged Eker rats. Dendritic spine counts revealed an increased spine density in the cingulate gyrus in adult Ekers irrespective of housing conditions, whereas spine density in hippocampal pyramidal neurons was comparable across all genotypes and groups. Morphometric analysis of dendritic spines revealed age-related changes in spine morphology and density, which were responsive to animal genotype and environment. Taken together, our findings suggest that under TSC2 haploinsufficiency and mTORC1 hyperactivity, the expression of behavioural signs and neuroplasticity in Eker rats can be differentially influenced by the developmental stage and environment.
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Affiliation(s)
- Simon Granak
- National Institute of Mental Health, Klecany, Czech Republic.,Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Klara Tuckova
- National Institute of Mental Health, Klecany, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Viera Kutna
- National Institute of Mental Health, Klecany, Czech Republic
| | - Iveta Vojtechova
- National Institute of Mental Health, Klecany, Czech Republic.,Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Laura Bajkova
- Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Tomas Petrasek
- National Institute of Mental Health, Klecany, Czech Republic.,Laboratory of Neurophysiology of Memory, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Saak V Ovsepian
- Faculty of Science and Engineering, University of Greenwich London, Chatham Maritime, UK
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6
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Zhang J, Xu S, Liang K, Cao X, Ye Z, Huang W, Bai X, Zhang Y. LysM-positive neurons drive Tuberous Sclerosis Complex (TSC)-associated brain lesions. Cell Signal 2022; 100:110468. [PMID: 36115548 DOI: 10.1016/j.cellsig.2022.110468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 09/01/2022] [Accepted: 09/09/2022] [Indexed: 11/22/2022]
Abstract
Mutations of Tsc1 or Tsc2 can lead to excessive activation of mTORC1 and cause Tuberous Sclerosis Complex (TSC), which is an autosomal dominant genetic disease prominently characterized by seizures, mental retardation and multiorgan hamartoma. In TSC, pathological changes in the central nervous system are the leading cause of death and disability. In decades, series of rodent models have been established by mutating Tsc1 or Tsc2 genes in diverse neural cell lineages to investigate the underlying cellular and molecular mechanisms, however, the cellular origin triggering neural pathological changes in TSC is undetermined. In this study, we generated a novel mouse model involving conditional deletion of Tsc1 in lysozyme 2 (Lyz2)-positive cells which replicated several features of brain lesions including epileptic seizures, megalencephaly, highly enlarged pS6-positive neurons and astrogliosis. In addition, we confirmed that bone marrow-derived myeloid cells including microglia with Tsc1 deficiency are not the decisive lineage in the cerebral pathologies in TSC. These histological assays in our murine model indicate an essential contribution of Lyz2-positive neurons to TSC progression. The Lyz2-positive neural population-specific onset of Tsc1 loss in murine postnatal brain might be the key to pathological phenotypes. Our findings thus provided evidences supporting new insights into the role of Lyz2-positive neurons in TSC events.
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Affiliation(s)
- Jiahuan Zhang
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China
| | - Song Xu
- Department of Arthroplasty, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - Kangyan Liang
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China
| | - Xiong Cao
- Department of Neurobiology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China
| | - Zhixin Ye
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China
| | - Wenlan Huang
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China
| | - Xiaochun Bai
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
| | - Yue Zhang
- Department of Cell Biology, School of Basic Medical Science, Southern Medical University, Guangzhou 510515, China.
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7
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Kútna V, O'Leary VB, Hoschl C, Ovsepian SV. Cerebellar demyelination and neurodegeneration associated with mTORC1 hyperactivity may contribute to the developmental onset of autism-like neurobehavioral phenotype in a rat model. Autism Res 2022; 15:791-805. [PMID: 35178882 DOI: 10.1002/aur.2688] [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: 10/09/2021] [Revised: 01/14/2022] [Accepted: 02/06/2022] [Indexed: 02/06/2023]
Abstract
The cerebellum hosts more than half of all neurons of the human brain, with their organized activity playing a key role in coordinating motor functions. Cerebellar activity has also been implicated in the control of speech, communication, and social behavior, which are compromised in autism spectrum disorders (ASD). Despite major research advances, there is a shortage of mechanistic data relating cellular and molecular changes in the cerebellum to autistic behavior. We studied the impact of tuberous sclerosis complex 2 haploinsufficiency (Tsc2+/-) with downstream mTORC1 hyperactivity on cerebellar morphology and cellular organization in 1, 9, and 18 m.o. Eker rats, to determine possible structural correlates of an autism-like behavioural phenotype in this model. We report a greater developmental expansion of the cerebellar vermis, owing to enlarged white matter and thickened molecular layer. Histochemical and immunofluorescence data suggest age-related demyelination of central tract of the vermis, as evident from reduced level of myelin-basic protein in the arbora vitae. We also observed a higher number of astrocytes in Tsc2+/- rats of older age while the number of Purkinje cells (PCs) in these animals was lower than in wild-type controls. Unlike astrocytes and PCs, Bergmann glia remained unaltered at all ages in both genotypes, while the number of microglia was higher in Tsc2+/- rats of older age. The convergent evidence for a variety of age-dependent cellular changes in the cerebellum of rats associated with mTORC1 hyperactivity, thus, predicts an array of functional impairments, which may contribute to the developmental onset of an autism-like behavioral phenotype in this model. LAY SUMMARY: This study elucidates the impact of constitutive mTORC1 hyperactivity on cerebellar morphology and cellular organization in a rat model of autism and epilepsy. It describes age-dependent degeneration of Purkinje neurons, with demyelination of central tract as well as activation of microglia, and discusses the implications of these changes for neuro-behavioral phenotypes. The described changes provide new indications for the putative mechanisms underlying cerebellar impairments with their age-related onset, which may contribute to the pathobiology of autism, epilepsy, and related disorders.
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Affiliation(s)
- Viera Kútna
- Department of Experimental Neurobiology, National Institute of Mental Health, Klecany, Czech Republic
| | - Valerie Bríd O'Leary
- Department of Medical Genetics, Third Faculty of Medicine, Charles University, Prague 10, Czech Republic
| | - Cyril Hoschl
- Department of Experimental Neurobiology, National Institute of Mental Health, Klecany, Czech Republic.,Department of Psychiatry and Medical Psychology, Third Faculty of Medicine, Charles University, Prague 10, Czech Republic
| | - Saak V Ovsepian
- Faculty of Engineering and Science, University of Greenwich London, Chatham Maritime, Kent, ME4 4TB, United Kingdom
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8
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All-Trans Retinoic Acid Fosters the Multifarious U87MG Cell Line as a Model of Glioblastoma. Brain Sci 2021; 11:brainsci11060812. [PMID: 34207434 PMCID: PMC8234004 DOI: 10.3390/brainsci11060812] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 11/20/2022] Open
Abstract
Glioblastoma multiforme (GBM) is a primary brain cancer of poor prognosis, with existing treatments remaining essentially palliative. Current GBM therapy fails due to rapid reappearance of the heterogeneous neoplasm, with models suggesting that the recurrent growth is from treatment-resistant glioblastoma stem-like cells (GSCs). Whether GSCs depend on survival/proliferative cues from their surrounding microenvironmental niche, particularly surrounding the leading edge after treatment remains unknown. Simulating human GBM in the laboratory relies on representative cell lines and xenograft models for translational medicine. Due to U87MG source discrepancy and differential proliferation responses to retinoic acid treatment, this study highlights the challenges faced by laboratory scientists working with this representative GBM cell line. Investigating the response to all trans-retinoic acid (ATRA) revealed its sequestering of the prominin-1 stem cell marker. ICAM-1 universally present throughout U87MG was enhanced by ATRA, of interest for chemotherapy targeting studies. ATRA triggered diverse expression patterns of long non-coding RNAs PARTICLE and GAS5 in the leading edge and established monolayer growth zone microenvironment. Karyotyping confirmed the female origin of U87MG sourced from Europe. Passaging U87MG revealed the presence of chromosomal anomalies reflective of structural genomic alterations in this glioblastoma cell line. All evidence considered, this study exposes further phenotypic nuances of U87MG which may belie researchers seeking data contributing towards the elusive cure for GBM.
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9
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Petrasek T, Vojtechova I, Klovrza O, Tuckova K, Vejmola C, Rak J, Sulakova A, Kaping D, Bernhardt N, de Vries PJ, Otahal J, Waltereit R. mTOR inhibitor improves autistic-like behaviors related to Tsc2 haploinsufficiency but not following developmental status epilepticus. J Neurodev Disord 2021; 13:14. [PMID: 33863288 PMCID: PMC8052752 DOI: 10.1186/s11689-021-09357-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 02/18/2021] [Indexed: 12/18/2022] Open
Abstract
Background Tuberous sclerosis complex (TSC), a multi-system genetic disorder often associated with autism spectrum disorder (ASD), is caused by mutations of TSC1 or TSC2, which lead to constitutive overactivation of mammalian target of rapamycin (mTOR). In several Tsc1+/- and Tsc2+/- animal models, cognitive and social behavior deficits were reversed by mTOR inhibitors. However, phase II studies have not shown amelioration of ASD and cognitive deficits in individuals with TSC during mTOR inhibitor therapy. We asked here if developmental epilepsy, common in the majority of individuals with TSC but absent in most animal models, could explain the discrepancy. Methods At postnatal day P12, developmental status epilepticus (DSE) was induced in male Tsc2+/- (Eker) and wild-type rats, establishing four experimental groups including controls. In adult animals (n = 36), the behavior was assessed in the paradigms of social interaction test, elevated plus-maze, light-dark test, Y-maze, and novel object recognition. The testing was carried out before medication (T1), during a 2-week treatment with the mTOR inhibitor everolimus (T2) and after an 8-week washing-out (T3). Electroencephalographic (EEG) activity was recorded in a separate set of animals (n = 18). Results Both Tsc2+/- mutation and DSE caused social behavior deficits and epileptiform EEG abnormalities (T1). Everolimus led to a persistent improvement of the social deficit induced by Tsc2+/-, while deficits related to DSE did not respond to everolimus (T2, T3). Conclusions These findings may contribute to an explanation why ASD symptoms in individuals with TSC, where comorbid early-onset epilepsy is common, were not reliably ameliorated by mTOR inhibitors in clinical studies. Supplementary Information The online version contains supplementary material available at 10.1186/s11689-021-09357-2.
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Affiliation(s)
- Tomas Petrasek
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic.
| | - Iveta Vojtechova
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic.,First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Ondrej Klovrza
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic.,Second Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Klara Tuckova
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Cestmir Vejmola
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic
| | - Jakub Rak
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic
| | - Anna Sulakova
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic
| | - Daniel Kaping
- National Institute of Mental Health, Topolova 748, 250 67, Klecany, Czech Republic
| | - Nadine Bernhardt
- Department of Psychiatry, University Hospital and Medical Faculty Carl Gustav Carus, Technical University of Dresden, Dresden, Germany
| | - Petrus J de Vries
- Division of Child & Adolescent Psychiatry, University of Cape Town, Cape Town, South Africa
| | - Jakub Otahal
- Department of Developmental Epileptology, Institute of Physiology CAS, Prague, Czech Republic
| | - Robert Waltereit
- Department of Child and Adolescent Psychiatry, University Hospital and Medical Faculty Carl Gustav Carus, Technical University of Dresden, Dresden, Germany. .,Department of Child and Adolescent Psychiatry, University Medical Center Göttingen, Von-Siebold-Str. 5, 37075, Göttingen, Germany.
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10
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Kútna V, O'Leary VB, Newman E, Hoschl C, Ovsepian SV. Revisiting Brain Tuberous Sclerosis Complex in Rat and Human: Shared Molecular and Cellular Pathology Leads to Distinct Neurophysiological and Behavioral Phenotypes. Neurotherapeutics 2021; 18:845-858. [PMID: 33398801 PMCID: PMC8423952 DOI: 10.1007/s13311-020-01000-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2020] [Indexed: 12/27/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is a dominant autosomal genetic disorder caused by loss-of-function mutations in TSC1 and TSC2, which lead to constitutive activation of the mammalian target of rapamycin C1 (mTORC1) with its decoupling from regulatory inputs. Because mTORC1 integrates an array of molecular signals controlling protein synthesis and energy metabolism, its unrestrained activation inflates cell growth and division, resulting in the development of benign tumors in the brain and other organs. In humans, brain malformations typically manifest through a range of neuropsychiatric symptoms, among which mental retardation, intellectual disabilities with signs of autism, and refractory seizures, which are the most prominent. TSC in the rat brain presents the first-rate approximation of cellular and molecular pathology of the human brain, showing many instructive characteristics. Nevertheless, the developmental profile and distribution of lesions in the rat brain, with neurophysiological and behavioral manifestation, deviate considerably from humans, raising numerous research and translational questions. In this study, we revisit brain TSC in human and Eker rats to relate their histopathological, electrophysiological, and neurobehavioral characteristics. We discuss shared and distinct aspects of the pathology and consider factors contributing to phenotypic discrepancies. Given the shared genetic cause and molecular pathology, phenotypic deviations suggest an incomplete understanding of the disease. Narrowing the knowledge gap in the future should not only improve the characterization of the TSC rat model but also explain considerable variability in the clinical manifestation of the disease in humans.
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Affiliation(s)
- Viera Kútna
- Department of Experimental Neurobiology, National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic.
| | - Valerie B O'Leary
- Department of Medical Genetics, Third Faculty of Medicine of Charles University, Ruská 87, 100 00, Prague, Czech Republic
| | - Ehren Newman
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, USA
| | - Cyril Hoschl
- Department of Experimental Neurobiology, National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic
- Department of Psychiatry and Medical Psychology, Third Faculty of Medicine of Charles University, Ruská 87, 100 00, Prague, Czech Republic
| | - Saak V Ovsepian
- Department of Experimental Neurobiology, National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic.
- Department of Psychiatry and Medical Psychology, Third Faculty of Medicine of Charles University, Ruská 87, 100 00, Prague, Czech Republic.
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