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Percy AK, Ananth A, Neul JL. Rett Syndrome: The Emerging Landscape of Treatment Strategies. CNS Drugs 2024:10.1007/s40263-024-01106-y. [PMID: 39251501 DOI: 10.1007/s40263-024-01106-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/27/2024] [Indexed: 09/11/2024]
Abstract
Rett syndrome (RTT) has enjoyed remarkable progress in achieving specific therapies. RTT, a unique neurodevelopmental disorder first described in 1966, progressed slowly until the landmark paper of Hagberg and colleagues in 1983. Thereafter, rapid advances were achieved including the development of specific diagnostic criteria and the active search for a genetic etiology, resulting 16 years later in identification of variants in the methyl-CpG-binding protein (MECP2) gene located at Xq28. Shortly thereafter, the NIH Office of Rare Diseases funded the RTT Natural History Study (NHS) in 2003, initiating the acquisition of natural history data on clinical features from a large population of individuals with RTT. This information was essential for advancement of clinical trials to provide specific therapies for this disorder. In the process, the International Rett Syndrome Association (IRSA) was formed (now the International Rett Syndrome Foundation-IRSF), which participated directly in encouraging and expanding enrollment in the NHS and, subsequently, in developing the SCOUT program to facilitate testing of potential therapeutic agents in a mouse model of RTT. The overall objective was to review clinical characteristics developed from the NHS and to discuss the status of specific therapies for this progressive neurodevelopmental disorder. The NHS study provided critical information on RTT: growth, anthropometrics, longevity, key comorbidities including epilepsy, breath abnormalities, gastroesophageal dysfunction, scoliosis and other orthopedic issues, puberty, behavior and anxiety, and progressive motor deterioration including the appearance of parkinsonian features. Phenotype-genotype correlations were noted including the role of X chromosome inactivation. Development of clinical severity and quality of life measures also proved critical for subsequent clinical trials. Further, development of biochemical and neurophysiologic biomarkers offered further endpoints for clinical trials. Initial clinical trials prior to the NHS were ineffective, but advances resulting from the NHS and other studies worldwide promoted significant interest from pharmaceutical firms resulting in several clinical trials. While some of these have been unrewarding such as sarizotan, others have been quite promising including the approval of trofinetide by the FDA in 2023 as the first agent available for specific treatment of RTT. Blarcamesine has been trialed in phase 3 trials, 14 agents have been studied in phase 2 trials, and 7 agents are being evaluated in preclinical/translational studies. A landmark study in 2007 by Guy et al. demonstrated that activation of a normal MECP2 gene in a null mouse model resulted in significant improvement. Gene replacement therapy has advanced through translational studies to two current phase 1/2 clinical trials (Taysha102 and Neurogene-401). Additional genetic therapies are also under study including gene editing, RNA editing, and X-chromosome reactivation. Taken together, progress in understanding and treating RTT over the past 40 years has been remarkable. This suggests that further advances can be expected.
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Affiliation(s)
- Alan K Percy
- University of Alabama at Birmingham, Lowder Bldg 416, Birmingham, AL, 35233, USA.
| | - Amitha Ananth
- University of Alabama at Birmingham, Lowder Bldg 416, Birmingham, AL, 35233, USA
| | - Jeffrey L Neul
- Vanderbilt University Medical Center, Nashville, TN, USA
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2
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Laohavisudhi K, Sriwichaiin S, Attachaipanich T, Wittayachamnankul B, Chattipakorn N, Chattipakorn S. Mechanistic insights into Lipocalin-2 in ischemic stroke and hemorrhagic brain injury: Integrating animal and clinical studies. Exp Neurol 2024; 379:114885. [PMID: 38996863 DOI: 10.1016/j.expneurol.2024.114885] [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: 05/06/2024] [Revised: 06/21/2024] [Accepted: 07/08/2024] [Indexed: 07/14/2024]
Abstract
Brain injuries, including strokes and traumatic brain injuries (TBI), are a major global health concern, contributing significantly to both mortality and long-term disability. Recent research has identified lipocalin-2 (LCN2), a glycoprotein secreted by various brain cells, as a key factor in influencing brain injury outcomes. Evidence from animal and clinical studies firmly establishes the pivotal role of LCN2 in driving the inflammatory responses triggered by damage to brain tissue. Furthermore, increased LCN2 promotes cellular differentiation, blood-brain barrier breakdown, and decreases cell viability. Interventions with LCN2 inhibitors attenuated brain injury through a reduction in the inflammation process and enhanced cellular viability. Potential mechanisms of LCN2 involve several pathways including the Janus kinase-2 (JAK2)-signal transducers and the transcription-3 (STAT3) signaling, hypoxia-inducible factor 1-alpha (HIF-1α)-LCN2-vascular endothelial growth factor alpha (VEGFα), and the PKR-like ER kinase (PERK) pathways. LCN2 itself interacts with diverse inflammatory cytokines in TBI and intracranial hemorrhage (ICH), resulting in disruption of the blood-brain barrier, increased programmed cell death, and an imbalance in iron homeostasis. Clinical studies have also shown that increased LCN2 level can act as a prognostic biomarker of outcomes following brain injuries. Therefore, this review aims to comprehensively evaluate the role and underlying mechanisms of LCN2 in brain injuries, including stroke and TBI, and explore potential therapeutic interventions targeting LCN2 in these conditions.
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Affiliation(s)
- Korsin Laohavisudhi
- Department of Emergency Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Sirawit Sriwichaiin
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai 50200, Thailand; Cardiac Electrophysiology Research Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Tanawat Attachaipanich
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai 50200, Thailand; Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Borwon Wittayachamnankul
- Department of Emergency Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Nipon Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai 50200, Thailand; Cardiac Electrophysiology Research Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; The Academy of Science, The Royal Society of Thailand, Bangkok, Thailand
| | - Siriporn Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai 50200, Thailand; Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand.
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Leoncini S, Boasiako L, Di Lucia S, Beker A, Scandurra V, Vignoli A, Canevini MP, Prato G, Nobili L, Nicotera AG, Di Rosa G, Chiarini MBT, Cutrera R, Grosso S, Lazzeri G, Tongiorgi E, Morano P, Botteghi M, Barducci A, De Felice C. 24-h continuous non-invasive multiparameter home monitoring of vitals in patients with Rett syndrome by an innovative wearable technology: evidence of an overlooked chronic fatigue status. Front Neurol 2024; 15:1388506. [PMID: 38952469 PMCID: PMC11215834 DOI: 10.3389/fneur.2024.1388506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/13/2024] [Indexed: 07/03/2024] Open
Abstract
Background Sleep is disturbed in Rett syndrome (RTT), a rare and progressive neurodevelopmental disorder primarily affecting female patients (prevalence 7.1/100,000 female patients) linked to pathogenic variations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene. Autonomic nervous system dysfunction with a predominance of the sympathetic nervous system (SNS) over the parasympathetic nervous system (PSNS) is reported in RTT, along with exercise fatigue and increased sudden death risk. The aim of the present study was to test the feasibility of a continuous 24 h non-invasive home monitoring of the biological vitals (biovitals) by an innovative wearable sensor device in pediatric and adolescent/adult RTT patients. Methods A total of 10 female patients (mean age 18.3 ± 9.4 years, range 4.7-35.5 years) with typical RTT and MECP2 pathogenic variations were enrolled. Clinical severity was assessed by validated scales. Heart rate (HR), respiratory rate (RR), and skin temperature (SkT) were monitored by the YouCare Wearable Medical Device (Accyourate Group SpA, L'Aquila, Italy). The average percentage of maximum HR (HRmax%) was calculated. Heart rate variability (HRV) was expressed by consolidated time-domain and frequency-domain parameters. The HR/LF (low frequency) ratio, indicating SNS activation under dynamic exercise, was calculated. Simultaneous continuous measurement of indoor air quality variables was performed and the patients' contributions to the surrounding water vapor partial pressure [PH2O (pt)] and carbon dioxide [PCO2 (pt)] were indirectly estimated. Results Of the 6,559.79 h of biovital recordings, 5051.03 h (77%) were valid for data interpretation. Sleep and wake hours were 9.0 ± 1.1 h and 14.9 ± 1.1 h, respectively. HRmax % [median: 71.86% (interquartile range 61.03-82%)] and HR/LF [median: 3.75 (interquartile range 3.19-5.05)] were elevated, independent from the wake-sleep cycle. The majority of HRV time- and frequency-domain parameters were significantly higher in the pediatric patients (p ≤ 0.031). The HRV HR/LF ratio was associated with phenotype severity, disease progression, clinical sleep disorder, subclinical hypoxia, and electroencephalographic observations of multifocal epileptic activity and general background slowing. Conclusion Our findings indicate the feasibility of a continuous 24-h non-invasive home monitoring of biovital parameters in RTT. Moreover, for the first time, HRmax% and the HR/LF ratio were identified as potential objective markers of fatigue, illness severity, and disease progression.
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Affiliation(s)
- Silvia Leoncini
- Rett Syndrome Trial Center, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
- Neonatal Intensive Care Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
- U.O.S.A. Programmazione e Ricerca Clinica, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Lidia Boasiako
- Rett Syndrome Trial Center, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
- Neonatal Intensive Care Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Sofia Di Lucia
- Neonatal Intensive Care Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | | | - Valeria Scandurra
- Child Neuropsychiatry Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Aglaia Vignoli
- Childhood and Adolescence Neurology and Psychiatry Unit, ASST GOM Niguarda, Milan, Italy
| | - Maria Paola Canevini
- Epilepsy Center – Sleep Medicine Center, Childhood and Adolescence Neuropsychiatry Unit, ASST Santi Paolo e Carlo, San Paolo Hospital, Milan, Italy
| | - Giulia Prato
- Child Neuropsychiatry Unit, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Lino Nobili
- Child Neuropsychiatry Unit, IRCCS Istituto Giannina Gaslini, Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health (DINOGMI), University of Genova, Genova, Italy
| | | | - Gabriella Di Rosa
- Child Neuropsychiatry Unit, University Hospital “G. Martino”, Messina, Italy
- Department of Biomedical and Dental Sciences and of Morphological and Functional Imaging (BIOMORF), University of Messina, Messina, Italy
| | - Maria Beatrice Testa Chiarini
- Pneumology and Cystic Fibrosis Unit, Academic Department of Pediatrics, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Renato Cutrera
- Pneumology and Cystic Fibrosis Unit, Academic Department of Pediatrics, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Salvatore Grosso
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
- Pediatrics Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Giacomo Lazzeri
- U.O.S.A. Programmazione e Ricerca Clinica, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Enrico Tongiorgi
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | | | - Matteo Botteghi
- Department of Clinical and Molecular Sciences – Experimental Pathology Research Group, Università Politecnica delle Marche, Ancona, Italy
- Medical Physics Activities Coordination Centre – Alma Mater Studiorum – University of Bologna, Bologna, Italy
| | | | - Claudio De Felice
- Rett Syndrome Trial Center, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
- Neonatal Intensive Care Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
- Pediatrics Unit, University Hospital Azienda Ospedaliera Universitaria Senese, Siena, Italy
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Pasqui A, Cicaloni V, Tinti L, Guiotto A, Tinti C, Mori A, Bruttini M, Hayek J, Pecorelli A, Salvini L, Valacchi G. A proteomic approach to investigate the role of the MECP2 gene mutation in Rett syndrome redox regulatory pathways. Arch Biochem Biophys 2024; 752:109860. [PMID: 38110111 DOI: 10.1016/j.abb.2023.109860] [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: 11/02/2023] [Revised: 12/11/2023] [Accepted: 12/11/2023] [Indexed: 12/20/2023]
Abstract
Mutations in the X-linked methyl-CpG-binding 2 (MECP2) gene lead to Rett Syndrome (RTT; OMIM 312750), a devasting neurodevelopmental disorder. RTT clinical manifestations are complex and with different degrees of severity, going from autistic-like behavior to loss of acquired speech, motor skills and cardiac problems. Furthermore, the correlation between the type of MECP2 mutation and the clinical phenotype is still not fully understood. Contextually, different genotypes can differently affect the patient's phenotype and omics methodologies such as proteomics could be an important tool for a molecular characterization of genotype/phenotype correlation. The aim of our study was focused on evaluating RTT oxidative stress (OS) responses related to specific MECP2 gene mutations by using proteomics and bioinformatics approaches. Primary fibroblasts isolated from patients affected by R133C and R255× mutations were compared to healthy controls (HC). After clustering primary dermal fibroblasts based on their specific MECP2 mutations, fibroblast-derived protein samples were qualitative and quantitative analyzed, using a label free quantification (LFQ) analysis by mass spectrometry (MS), achieving a preliminary correlation for RTT genotype/phenotype. Among the identified proteins involved in redox regulation pathways, NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1) was found to be absent in R255× cells, while it was present in R133C and in HC fibroblasts. Moreover, NQO1 aberrant gene regulation was also confirmed when cells were challenged with 100 μM hydrogen peroxide (H2O2). In conclusion, by employing a multidisciplinary approach encompassing proteomics and bioinformatics analyses, as well as molecular biology assays, the study uncovered phenotypic responses linked to specific MECP2 gene mutations. These findings contribute to a better understanding of the complexity of RTT molecular pathways, confirming the high heterogeneity among the patients.
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Affiliation(s)
- Arianna Pasqui
- Toscana Life Science Foundation, Siena, Italy; Department of Biotechnology, Chemistry and Pharmacy, University of Siena, 53100 Siena, Italy
| | | | - Laura Tinti
- Toscana Life Science Foundation, Siena, Italy
| | - Anna Guiotto
- Plants for Human Health Institute, Animal Science Department, North Carolina State University, North Carolina Research Campus, Kannapolis, NC 28081, USA; Department of Environmental and Prevention Sciences, University of Ferrara, 44121 Ferrara, Italy
| | | | - Alessia Mori
- Diabetes Unit, Department of Medicine, Surgery and Neurosciences, University of Siena Italy; Fondazione Umberto Di Mario ONLUS c/o Toscana Life Science, Siena, Italy; Tuscany Centre for Precision Medicine (CReMeP), Siena 53100, Italy
| | - Marco Bruttini
- Diabetes Unit, Department of Medicine, Surgery and Neurosciences, University of Siena Italy; Fondazione Umberto Di Mario ONLUS c/o Toscana Life Science, Siena, Italy; Tuscany Centre for Precision Medicine (CReMeP), Siena 53100, Italy
| | | | - Alessandra Pecorelli
- Plants for Human Health Institute, Animal Science Department, North Carolina State University, North Carolina Research Campus, Kannapolis, NC 28081, USA; Department of Environmental and Prevention Sciences, University of Ferrara, 44121 Ferrara, Italy.
| | | | - Giuseppe Valacchi
- Plants for Human Health Institute, Animal Science Department, North Carolina State University, North Carolina Research Campus, Kannapolis, NC 28081, USA; Department of Environmental and Prevention Sciences, University of Ferrara, 44121 Ferrara, Italy; Department of Food and Nutrition, Kyung Hee University, Seoul 02447, Republic of Korea.
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Ramirez JM, Carroll MS, Burgraff N, Rand CM, Weese-Mayer DE. A narrative review of the mechanisms and consequences of intermittent hypoxia and the role of advanced analytic techniques in pediatric autonomic disorders. Clin Auton Res 2023; 33:287-300. [PMID: 37326924 DOI: 10.1007/s10286-023-00958-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 05/25/2023] [Indexed: 06/17/2023]
Abstract
Disorders of autonomic functions are typically characterized by disturbances in multiple organ systems. These disturbances are often comorbidities of common and rare diseases, such as epilepsy, sleep apnea, Rett syndrome, congenital heart disease or mitochondrial diseases. Characteristic of many autonomic disorders is the association with intermittent hypoxia and oxidative stress, which can cause or exaggerate a variety of other autonomic dysfunctions, making the treatment and management of these syndromes very complex. In this review we discuss the cellular mechanisms by which intermittent hypoxia can trigger a cascade of molecular, cellular and network events that result in the dysregulation of multiple organ systems. We also describe the importance of computational approaches, artificial intelligence and the analysis of big data to better characterize and recognize the interconnectedness of the various autonomic and non-autonomic symptoms. These techniques can lead to a better understanding of the progression of autonomic disorders, ultimately resulting in better care and management.
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Affiliation(s)
- Jan-Marino Ramirez
- Center for Integrative Brain Research, Seattle Children's Research Institute, 1900 Ninth Avenue, Seattle, WA, 98101, USA.
- Departments of Neurological Surgery and Pediatrics, University of Washington School of Medicine, 1900 Ninth Avenue, Seattle, WA, 98101, USA.
| | - Michael S Carroll
- Data Analytics and Reporting, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Division of Autonomic Medicine, Stanley Manne Children's Research Institute at Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Nicholas Burgraff
- Center for Integrative Brain Research, Seattle Children's Research Institute, 1900 Ninth Avenue, Seattle, WA, 98101, USA
| | - Casey M Rand
- Division of Autonomic Medicine, Stanley Manne Children's Research Institute at Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Debra E Weese-Mayer
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- Division of Autonomic Medicine, Stanley Manne Children's Research Institute at Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
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Baroncelli L, Auel S, Rinne L, Schuster AK, Brand V, Kempkes B, Dietrich K, Müller M. Oral Feeding of an Antioxidant Cocktail as a Therapeutic Strategy in a Mouse Model of Rett Syndrome: Merits and Limitations of Long-Term Treatment. Antioxidants (Basel) 2022; 11:antiox11071406. [PMID: 35883897 PMCID: PMC9311910 DOI: 10.3390/antiox11071406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 02/01/2023] Open
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder that typically arises from spontaneous germline mutations in the X-chromosomal methyl-CpG binding protein 2 (MECP2) gene. For the first 6–18 months of life, the development of the mostly female patients appears normal. Subsequently, cognitive impairment, motor disturbances, hand stereotypies, epilepsy, and irregular breathing manifest, with previously learned skills being lost. Early mitochondrial impairment and a systemic oxidative burden are part of the complex pathogenesis, and contribute to disease progression. Accordingly, partial therapeutic merits of redox-stabilizing and antioxidant (AO) treatments were reported in RTT patients and Mecp2-mutant mice. Pursuing these findings, we conducted a full preclinical trial on male and female mice to define the therapeutic value of an orally administered AO cocktail composed of vitamin E, N-acetylcysteine, and α-lipoic acid. AO treatment ameliorated some of the microcephaly-related aspects. Moreover, the reduced growth, lowered blood glucose levels, and the hippocampal synaptic plasticity of Mecp2−/y mice improved. However, the first-time detected intensified oxidative DNA damage in Mecp2-mutant cortex persisted. The behavioral performance, breathing regularity, and life expectancy of Mecp2-mutant mice did not improve upon AO treatment. Long-term-treated Mecp2+/− mice eventually became obese. In conclusion, the AO cocktail ameliorated a subset of symptoms of the complex RTT-related phenotype, thereby further confirming the potential merits of AO-based pharmacotherapies. Yet, it also became evident that long-term AO treatment may lose efficacy and even aggravate the metabolic disturbances in RTT. This emphasizes the importance of a constantly well-balanced redox balance for systemic well-being.
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Affiliation(s)
- Laura Baroncelli
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
- Institute of Neuroscience, National Research Council (CNR), via Giuseppe Moruzzi 1, I-56124 Pisa, Italy
- Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Viale del Tirreno 331, I-56128 Pisa, Italy
| | - Stefanie Auel
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
| | - Lena Rinne
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
| | - Ann-Kathrin Schuster
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
| | - Victoria Brand
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
| | - Belinda Kempkes
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
| | - Katharina Dietrich
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
| | - Michael Müller
- Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany; (L.B.); (S.A.); (L.R.); (A.-K.S.); (V.B.); (B.K.); (K.D.)
- Correspondence: ; Tel.: +49-551-39-22933
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Delayed Ventricular Repolarization and Sodium Channel Current Modification in a Mouse Model of Rett Syndrome. Int J Mol Sci 2022; 23:ijms23105735. [PMID: 35628543 PMCID: PMC9147596 DOI: 10.3390/ijms23105735] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 02/01/2023] Open
Abstract
Rett syndrome (RTT) is a severe developmental disorder that is strongly linked to mutations in the MECP2 gene. RTT has been associated with sudden unexplained death and ECG QT interval prolongation. There are mixed reports regarding QT prolongation in mouse models of RTT, with some evidence that loss of Mecp2 function enhances cardiac late Na current, INa,Late. The present study was undertaken in order to investigate both ECG and ventricular AP characteristics in the Mecp2Null/Y male murine RTT model and to interrogate both fast INa and INa,Late in myocytes from the model. ECG recordings from 8-10-week-old Mecp2Null/Y male mice revealed prolongation of the QT and rate corrected QT (QTc) intervals and QRS widening compared to wild-type (WT) controls. Action potentials (APs) from Mecp2Null/Y myocytes exhibited longer APD75 and APD90 values, increased triangulation and instability. INa,Late was also significantly larger in Mecp2Null/Y than WT myocytes and was insensitive to the Nav1.8 inhibitor A-803467. Selective recordings of fast INa revealed a decrease in peak current amplitude without significant voltage shifts in activation or inactivation V0.5. Fast INa 'window current' was reduced in RTT myocytes; small but significant alterations of inactivation and reactivation time-courses were detected. Effects of two INa,Late inhibitors, ranolazine and GS-6615 (eleclazine), were investigated. Treatment with 30 µM ranolazine produced similar levels of inhibition of INa,Late in WT and Mecp2Null/Y myocytes, but produced ventricular AP prolongation not abbreviation. In contrast, 10 µM GS-6615 both inhibited INa,Late and shortened ventricular AP duration. The observed changes in INa and INa,Late can account for the corresponding ECG changes in this RTT model. GS-6615 merits further investigation as a potential treatment for QT prolongation in RTT.
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Signorini C, De Felice C, Durand T, Galano JM, Oger C, Leoncini S, Hayek J, Lee JCY, Lund TC, Orchard PJ. Isoprostanoid Plasma Levels Are Relevant to Cerebral Adrenoleukodystrophy Disease. Life (Basel) 2022; 12:146. [PMID: 35207434 PMCID: PMC8874514 DOI: 10.3390/life12020146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 11/16/2022] Open
Abstract
Cerebral adrenoleukodystrophy (ALD) is a rare neuroinflammatory disorder characterized by progressive demyelination. Mutations within the ABCD1 gene result in very long-chain fatty acid (VLCFA) accumulation within the peroxisome, particularly in the brain. While this VLCFA accumulation is known to be the driving cause of the disease, oxidative stress can be a contributing factor. For patients with early cerebral disease, allogeneic hematopoietic stem cell transplantation (HSCT) is the standard of care, and this can be supported by antioxidants. To evaluate the involvement of fatty acid oxidation in the disease, F2-isoprostanes (F2-IsoPs), F2-dihomo-isoprostanes (F2-dihomo-IsoPs) and F4-neuroprostanes (F4-NeuroPs)-which are oxygenated metabolites of arachidonic (ARA), adrenic (AdA) and docosahexaenoic (DHA) acids, respectively-in plasma samples from ALD subjects (n = 20)-with various phenotypes of the disease-were measured. Three ALD groups were classified according to patients with: (1) confirmed diagnosis of ALD but without cerebral disease; (2) cerebral disease in early period post-HSCT (<100 days post-HSCT) and on intravenous N-acetyl-L-cysteine (NAC) treatment; (3) cerebral disease in late period post-HSCT (beyond 100 days post-HSCT) and off NAC therapy. In our observation, when compared to healthy subjects (n = 29), in ALD (i), F2-IsoPs levels were significantly (p < 0.01) increased in all patients, with the single exception of the early ALD and on NAC subjects; (ii) significant elevated (p < 0.0001) amounts of F2-dihomo-IsoPs were detected, with the exception of patients with a lack of cerebral disease; (iii), a significant increase (p < 0.003) in F4-NeuroP plasma levels was detected in all ALD patients. Moreover, F2-IsoPs plasma levels were significantly higher (p = 0.038) in early ALD in comparison to late ALD stage, and F4-NeuroPs were significantly lower (p = 0.012) in ALD subjects with a lack of cerebral disease in comparison to the late disease stage. Remarkably, plasma amounts of all investigated isoprostanoids were shown to discriminate ALD patients vs. healthy subjects. Altogether, isoprostanoids are relevant to the phenotype of X-ALD and may be helpful in predicting the presence of cerebral disease and establishing the risk of progression.
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Affiliation(s)
- Cinzia Signorini
- Department of Molecular and Developmental Medicine, University of Siena, 53100 Siena, Italy
| | - Claudio De Felice
- Neonatal Intensive Care Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy;
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (C.O.)
| | - Jean-Marie Galano
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (C.O.)
| | - Camille Oger
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (C.O.)
| | - Silvia Leoncini
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy; (S.L.); (J.H.)
| | - Joussef Hayek
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy; (S.L.); (J.H.)
- Pediatric Speciality Center “L’Isola di Bau”, Certaldo, 50052 Florence, Italy
| | | | - Troy C. Lund
- Division of Pediatric Blood and Marrow Transplantation, University of Minnesota, Minneapolis, MN 55455, USA; (T.C.L.); (P.J.O.)
| | - Paul J. Orchard
- Division of Pediatric Blood and Marrow Transplantation, University of Minnesota, Minneapolis, MN 55455, USA; (T.C.L.); (P.J.O.)
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9
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Ramirez JM, Karlen-Amarante M, Wang JDJ, Huff A, Burgraff N. Breathing disturbances in Rett syndrome. HANDBOOK OF CLINICAL NEUROLOGY 2022; 189:139-151. [PMID: 36031301 PMCID: PMC10029146 DOI: 10.1016/b978-0-323-91532-8.00018-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Rett Syndrome is an X-linked neurological disorder characterized by behavioral and neurological regression, seizures, motor deficits, and dysautonomia. A particularly prominent presentation includes breathing abnormalities characterized by breathing irregularities, hyperventilation, repetitive breathholding during wakefulness, obstructive and central apneas during sleep, and abnormal responses to hypoxia and hypercapnia. The condition and pathology of the respiratory system is further complicated by dysfunctions of breathing-motor coordination, which is reflected in dysphagia. The discovery of the X-linked mutations in the MECP2 gene has transformed our understanding of the cellular and molecular mechanisms that are at the root of various clinical phenotypes. However, the genotype-phenotype relationship is complicated by various factors which include not only X-inactivation but also consequences of the intermittent hypoxia and oxidative stress associated with the breathing abnormalities.
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Affiliation(s)
- Jan-Marino Ramirez
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States; Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA, United States.
| | - Marlusa Karlen-Amarante
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Jia-Der Ju Wang
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Alyssa Huff
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Nicholas Burgraff
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
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10
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Franzoni F, Scarfò G, Guidotti S, Fusi J, Asomov M, Pruneti C. Oxidative Stress and Cognitive Decline: The Neuroprotective Role of Natural Antioxidants. Front Neurosci 2021; 15:729757. [PMID: 34720860 PMCID: PMC8548611 DOI: 10.3389/fnins.2021.729757] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/09/2021] [Indexed: 12/14/2022] Open
Abstract
Free- radicals (Oxygen and Nitrogen species) are formed in mitochondria during the oxidative phosphorylation. Their high reactivity, due to not-engaged electrons, leads to an increase of the oxidative stress. This condition affects above all the brain, that usually needs a large oxygen amount and in which there is the major possibility to accumulate "Reacting Species." Antioxidant molecules are fundamental in limiting free-radical damage, in particular in the central nervous system: the oxidative stress, in fact, seems to worsen the course of neurodegenerative diseases. The aim of this review is to sum up natural antioxidant molecules with the greatest neuroprotective properties against free radical genesis, understanding their relationship with the Central Nervous System.
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Affiliation(s)
- Ferdinando Franzoni
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Giorgia Scarfò
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Sara Guidotti
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Jonathan Fusi
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Muzaffar Asomov
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Carlo Pruneti
- Department of Medicine and Surgery, University of Parma, Parma, Italy
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11
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How Robust is the Evidence for a Role of Oxidative Stress in Autism Spectrum Disorders and Intellectual Disabilities? J Autism Dev Disord 2021; 51:1428-1445. [PMID: 32929662 PMCID: PMC8084796 DOI: 10.1007/s10803-020-04611-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Growing interest in the pathogenesis of autism spectrum disorders (ASDs) and other intellectual and developmental disabilities (IDD) has led to emerging evidence implicating a role for oxidative stress. However, understanding the strength of this association is made challenging by the use of a variety of purported biomarkers of oxidative stress, many of which have either uncertain specificity or flawed methods of analysis. This review aims to address this issue, which is widespread in the ASD and IDD literature, by providing readers with information concerning the strengths and limitations of the choice and analysis of biomarkers of oxidative stress. We highlight that biomarkers and assays should be specific, sensitive, reproducible, precise, robust, and chosen with careful consideration. Future studies should be sufficiently powered and address sample collection, processing, and storage which are, additionally, poorly considered, sources of bad practice, and potential errors. Only with these issues considered, will the data lead to conclusions as to the precise role of oxidative stress in ASDs and IDD.
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12
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Signorini C, Leoncini S, Durand T, Galano JM, Guy A, Bultel-Poncé V, Oger C, Lee JCY, Ciccoli L, Hayek J, De Felice C. Circulating 4-F 4t-Neuroprostane and 10-F 4t-Neuroprostane Are Related to MECP2 Gene Mutation and Natural History in Rett Syndrome. Int J Mol Sci 2021; 22:ijms22084240. [PMID: 33921863 PMCID: PMC8073126 DOI: 10.3390/ijms22084240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/10/2021] [Accepted: 04/15/2021] [Indexed: 12/20/2022] Open
Abstract
Neuroprostanes, a family of non-enzymatic metabolites of the docosahexaenoic acid, have been suggested as potential biomarkers for neurological diseases. Objective biological markers are strongly needed in Rett syndrome (RTT), which is a progressive X-linked neurodevelopmental disorder that is mainly caused by mutations in the methyl-CpG binding protein 2 (MECP2) gene with a predominant multisystemic phenotype. The aim of the study is to assess a possible association between MECP2 mutations or RTT disease progression and plasma levels of 4(RS)-4-F4t-neuroprostane (4-F4t-NeuroP) and 10(RS)-10-F4t-neuroprostane (10-F4t-NeuroP) in typical RTT patients with proven MECP2 gene mutation. Clinical severity and disease progression were assessed using the Rett clinical severity scale (RCSS) in n = 77 RTT patients. The 4-F4t-NeuroP and 10-F4t-NeuroP molecules were totally synthesized and used to identify the contents of the plasma of the patients. Neuroprostane levels were related to MECP2 mutation category (i.e., early truncating, gene deletion, late truncating, and missense), specific hotspot mutations (i.e., R106W, R133C, R168X, R255X, R270X, R294X, R306C, and T158M), and disease stage (II through IV). Circulating 4-F4t-NeuroP and 10-F4t-NeuroP were significantly related to (i) the type of MECP2 mutations where higher levels were associated to gene deletions (p ≤ 0.001); (ii) severity of common hotspot MECP2 mutation (large deletions, R168X, R255X, and R270X); (iii) disease stage, where higher concentrations were observed at stage II (p ≤ 0.002); and (iv) deficiency in walking (p ≤ 0.0003). This study indicates the biological significance of 4-F4t-NeuroP and 10-F4t-NeuroP as promising molecules to mark the disease progression and potentially gauge genotype-phenotype associations in RTT.
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Affiliation(s)
- Cinzia Signorini
- Department of Molecular and Developmental Medicine, University of Siena, 53100 Siena, Italy;
- Correspondence: (C.S.); (C.D.F.); Tel.: +39-0577-234499 (C.S.)
| | - Silvia Leoncini
- Neonatal Intensive Care Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy;
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy;
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (A.G.); (V.B.-P.); (C.O.)
| | - Jean-Marie Galano
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (A.G.); (V.B.-P.); (C.O.)
| | - Alexandre Guy
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (A.G.); (V.B.-P.); (C.O.)
| | - Valérie Bultel-Poncé
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (A.G.); (V.B.-P.); (C.O.)
| | - Camille Oger
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, CEDEX 5, 34093 Montpellier, France; (T.D.); (J.-M.G.); (A.G.); (V.B.-P.); (C.O.)
| | | | - Lucia Ciccoli
- Department of Molecular and Developmental Medicine, University of Siena, 53100 Siena, Italy;
| | - Joussef Hayek
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy;
- Pediatric Speciality Center “L’Isola di Bau”, 50052 Certaldo, Florence, Italy
| | - Claudio De Felice
- Neonatal Intensive Care Unit, Azienda Ospedaliera Universitaria Senese, 53100 Siena, Italy;
- Correspondence: (C.S.); (C.D.F.); Tel.: +39-0577-234499 (C.S.)
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13
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Correlation of dystonia severity and iron accumulation in Rett syndrome. Sci Rep 2021; 11:838. [PMID: 33436916 PMCID: PMC7804965 DOI: 10.1038/s41598-020-80723-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 12/21/2020] [Indexed: 01/29/2023] Open
Abstract
Individuals with Rett syndrome (RTT) commonly demonstrate Parkinsonian features and dystonia at teen age; however, the pathological reason remains unclear. Abnormal iron accumulation in deep gray matter were reported in some Parkinsonian-related disorders. In this study, we investigated the iron accumulation in deep gray matter of RTT and its correlation with dystonia severity. We recruited 18 RTT-diagnosed participants with MECP2 mutations, from age 4 to 28, and 28 age-gender matched controls and investigated the iron accumulation by susceptibility weighted image (SWI) in substantia nigra (SN), globus pallidus (GP), putamen, caudate nucleus, and thalamus. Pearson's correlation was applied for the relation between iron accumulation and dystonia severity. In RTT, the severity of dystonia scales showed significant increase in subjects older than 10 years, and the contrast ratios of SWI also showed significant differences in putamen, caudate nucleus and the average values of SN, putamen, and GP between RTT and controls. The age demonstrated moderate to high negative correlations with contrast ratios. The dystonia scales were correlated with the average contrast ratio of SN, putamen and GP, indicating iron accumulation in dopaminergic system and related grey matter. As the first SWI study for RTT individuals, we found increased iron deposition in dopaminergic system and related grey matter, which may partly explain the gradually increased dystonia.
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14
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Cristancho AG, Marsh ED. Epigenetics modifiers: potential hub for understanding and treating neurodevelopmental disorders from hypoxic injury. J Neurodev Disord 2020; 12:37. [PMID: 33327934 PMCID: PMC7745506 DOI: 10.1186/s11689-020-09344-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 11/13/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The fetal brain is adapted to the hypoxic conditions present during normal in utero development. Relatively more hypoxic states, either chronic or acute, are pathologic and can lead to significant long-term neurodevelopmental sequelae. In utero hypoxic injury is associated with neonatal mortality and millions of lives lived with varying degrees of disability. MAIN BODY Genetic studies of children with neurodevelopmental disease indicate that epigenetic modifiers regulating DNA methylation and histone remodeling are critical for normal brain development. Epigenetic modifiers are also regulated by environmental stimuli, such as hypoxia. Indeed, epigenetic modifiers that are mutated in children with genetic neurodevelopmental diseases are regulated by hypoxia in a number of preclinical models and may be part of the mechanism for the long-term neurodevelopmental sequelae seem in children with hypoxic brain injury. Thus, a comprehensive understanding the role of DNA methylation and histone modifications in hypoxic injury is critical for developing novel strategies to treat children with hypoxic injury. CONCLUSIONS This review focuses on our current understanding of the intersection between epigenetics, brain development, and hypoxia. Opportunities for the use of epigenetics as biomarkers of neurodevelopmental disease after hypoxic injury and potential clinical epigenetics targets to improve outcomes after injury are also discussed. While there have been many published studies on the epigenetics of hypoxia, more are needed in the developing brain in order to determine which epigenetic pathways may be most important for mitigating the long-term consequences of hypoxic brain injury.
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Affiliation(s)
- Ana G Cristancho
- Departments of Neurology and Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, USA
| | - Eric D Marsh
- Departments of Neurology and Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, USA.
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, USA.
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15
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Adebayo OL, Dewenter I, Rinne L, Golubiani G, Solomonia R, Müller M. Intensified mitochondrial hydrogen peroxide release occurs in all brain regions, affects male as well as female Rett mice, and constitutes a life-long burden. Arch Biochem Biophys 2020; 696:108666. [PMID: 33160914 DOI: 10.1016/j.abb.2020.108666] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/29/2020] [Accepted: 10/31/2020] [Indexed: 12/28/2022]
Abstract
The neurodevelopmental disorder Rett syndrome (RTT) affects mostly females. Upon an apparently normal initial development, cognitive impairment, irregular breathing, motor dysfunction, and epilepsy occur. The complex pathogenesis includes, among others, mitochondrial impairment, redox imbalance, and oxidative damage. As these arise already in neonatal Rett mice, they were proposed contributors of disease progression. Several mitochondrial studies in RTT used either full brains or selected brain regions only. Here, we mapped mitochondria-related ROS generation brain wide. Using sophisticated multi-sample spectrofluorimetry, H2O2 release by isolated mitochondria was quantified in a coupled reaction of Amplex UltraRed and horseradish peroxidase. All brain regions and the entire lifespan were characterized in male and female mice. In WT mice, mitochondrial H2O2 release was usually highest in cortex and lowest in hippocampus. Maximum rates occurred at postnatal day (PD) 10 and they slightly declined with further maturation. Already at PD 10, male and female Rett mice showed exaggerated mitochondrial H2O2 releases in first brain regions and persistent brain-wide increases from PD 50 on. Interestingly, female Rett mice were more intensely affected than male Rett mice, with their brainstem, midbrain and hippocampus being most severely struck. In conclusion, we used a reliable multi-sample cuvette-based assay on mitochondrial ROS release to perform brain-wide analyzes along the entire lifespan. Mitochondrial H2O2 release in Rett mice is intensified in all brain regions, affects hemizygous males and heterozygous females, and involves all maturational stages. Therefore, intensified mitochondrial H2O2 release seriously needs to be considered throughout RTT pathogenesis and may constitute a potential therapeutic target.
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Affiliation(s)
- Olusegun L Adebayo
- Georg-August-Universität Göttingen, Universitätsmedizin Göttingen, Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Germany; Department of Biochemistry, Faculty of Basic Medical Sciences, Redeemer's University, P.M.B. 230, Ede, Osun State, Nigeria
| | - Ina Dewenter
- Georg-August-Universität Göttingen, Universitätsmedizin Göttingen, Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Germany
| | - Lena Rinne
- Georg-August-Universität Göttingen, Universitätsmedizin Göttingen, Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Germany
| | - Gocha Golubiani
- Georg-August-Universität Göttingen, Universitätsmedizin Göttingen, Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Germany; Institute of Chemical Biology, Ilia State University, Tbilisi, Georgia
| | - Revaz Solomonia
- Institute of Chemical Biology, Ilia State University, Tbilisi, Georgia
| | - Michael Müller
- Georg-August-Universität Göttingen, Universitätsmedizin Göttingen, Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Germany.
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16
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Ramirez JM, Karlen-Amarante M, Wang JDJ, Bush NE, Carroll MS, Weese-Mayer DE, Huff A. The Pathophysiology of Rett Syndrome With a Focus on Breathing Dysfunctions. Physiology (Bethesda) 2020; 35:375-390. [PMID: 33052774 PMCID: PMC7864239 DOI: 10.1152/physiol.00008.2020] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 06/21/2020] [Accepted: 06/22/2020] [Indexed: 02/07/2023] Open
Abstract
Rett syndrome (RTT), an X-chromosome-linked neurological disorder, is characterized by serious pathophysiology, including breathing and feeding dysfunctions, and alteration of cardiorespiratory coupling, a consequence of multiple interrelated disturbances in the genetic and homeostatic regulation of central and peripheral neuronal networks, redox state, and control of inflammation. Characteristic breath-holds, obstructive sleep apnea, and aerophagia result in intermittent hypoxia, which, combined with mitochondrial dysfunction, causes oxidative stress-an important driver of the clinical presentation of RTT.
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Affiliation(s)
- Jan-Marino Ramirez
- Center for Integrative Brain Research, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, Washington
- Departments of Neurological Surgery and Pediatrics, University of Washington School of Medicine, Seattle, Washington
| | - Marlusa Karlen-Amarante
- Center for Integrative Brain Research, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, Washington
- Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University (UNESP), Araraquara, Brazil
| | - Jia-Der Ju Wang
- Center for Integrative Brain Research, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, Washington
| | - Nicholas E Bush
- Center for Integrative Brain Research, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, Washington
| | - Michael S Carroll
- Data Analytics and Reporting, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
- Division of Autonomic Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois
| | - Debra E Weese-Mayer
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
- Division of Autonomic Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois
| | - Alyssa Huff
- Center for Integrative Brain Research, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, Washington
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17
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Neutralization of Lipocalin-2 Diminishes Stroke-Reperfusion Injury. Int J Mol Sci 2020; 21:ijms21176253. [PMID: 32872405 PMCID: PMC7503651 DOI: 10.3390/ijms21176253] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 08/27/2020] [Accepted: 08/28/2020] [Indexed: 01/18/2023] Open
Abstract
Oxidative stress is a key contributor to the pathogenesis of stroke-reperfusion injury. Neuroinflammatory peptides released after ischemic stroke mediate reperfusion injury. Previous studies, including ours, have shown that lipocalin-2 (LCN2) is secreted in response to cerebral ischemia to promote reperfusion injury. Genetic deletion of LCN2 significantly reduces brain injury after stroke, suggesting that LCN2 is a mediator of reperfusion injury and a potential therapeutic target. Immunotherapy has the potential to harness neuroinflammatory responses and provides neuroprotection against stroke. Here we report that LCN2 was induced on the inner surface of cerebral endothelial cells, neutrophils, and astrocytes that gatekeep the blood–brain barrier (BBB) after stroke. LCN2 monoclonal antibody (mAb) specifically targeted LCN2 in vitro and in vivo, attenuating the induction of LCN2 and pro-inflammatory mediators (iNOS, IL-6, CCL2, and CCL9) after stroke. Administration of LCN2 mAb at 4 h after stroke significantly reduced neurological deficits, cerebral infarction, edema, BBB leakage, and infiltration of neutrophils. The binding epitope of LCN2 mAb was mapped to the β3 and β4 strands, which are responsible for maintaining the integrity of LCN2 cup-shaped structure. These data indicate that LCN2 can be pharmacologically targeted using a specific mAb to reduce reperfusion injury after stroke.
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18
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Fagiolini M, Patrizi A, LeBlanc J, Jin LW, Maezawa I, Sinnett S, Gray SJ, Molholm S, Foxe JJ, Johnston MV, Naidu S, Blue M, Hossain A, Kadam S, Zhao X, Chang Q, Zhou Z, Zoghbi H. Intellectual and Developmental Disabilities Research Centers: A Multidisciplinary Approach to Understand the Pathogenesis of Methyl-CpG Binding Protein 2-related Disorders. Neuroscience 2020; 445:190-206. [PMID: 32360592 DOI: 10.1016/j.neuroscience.2020.04.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 12/20/2022]
Abstract
Disruptions in the gene encoding methyl-CpG binding protein 2 (MECP2) underlie complex neurodevelopmental disorders including Rett Syndrome (RTT), MECP2 duplication disorder, intellectual disabilities, and autism. Significant progress has been made on the molecular and cellular basis of MECP2-related disorders providing a new framework for understanding how altered epigenetic landscape can derail the formation and refinement of neuronal circuits in early postnatal life and proper neurological function. This review will summarize selected major findings from the past years and particularly highlight the integrated and multidisciplinary work done at eight NIH-funded Intellectual and Developmental Disabilities Research Centers (IDDRC) across the US. Finally, we will outline a path forward with identification of reliable biomarkers and outcome measures, longitudinal preclinical and clinical studies, reproducibility of results across centers as a synergistic effort to decode and treat the pathogenesis of the complex MeCP2 disorders.
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Affiliation(s)
- Michela Fagiolini
- Children's Hospital Intellectual and Developmental Disabilities Research Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Annarita Patrizi
- Children's Hospital Intellectual and Developmental Disabilities Research Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jocelyn LeBlanc
- Children's Hospital Intellectual and Developmental Disabilities Research Center, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Lee-Way Jin
- UC Davis MIND Institute, University of California, Sacramento, CA, USA
| | - Izumi Maezawa
- UC Davis MIND Institute, University of California, Sacramento, CA, USA
| | - Sarah Sinnett
- UNC Intellectual and Developmental Disabilities Research Center, University of North Carolina, Gene Therapy Center and Dept. of Ophthalmology, Chapel Hill, NC, USA; Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Steven J Gray
- UNC Intellectual and Developmental Disabilities Research Center, University of North Carolina, Gene Therapy Center and Dept. of Ophthalmology, Chapel Hill, NC, USA; Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Sophie Molholm
- The Cognitive Neurophysiology Laboratory, Departments of Pediatrics, Neuroscience, and Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA
| | - John J Foxe
- The Cognitive Neurophysiology Laboratory, Ernest J. Del Monte Institute for Neuroscience, Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Michael V Johnston
- Kennedy Krieger Institute Intellectual and Developmental Disabilities Research Center/Hugo Moser Research Institute at Kennedy Krieger and Johns Hopkins School of Medicine, USA
| | - Sakkubai Naidu
- Kennedy Krieger Institute Intellectual and Developmental Disabilities Research Center/Hugo Moser Research Institute at Kennedy Krieger and Johns Hopkins School of Medicine, USA
| | - Mary Blue
- Kennedy Krieger Institute Intellectual and Developmental Disabilities Research Center/Hugo Moser Research Institute at Kennedy Krieger and Johns Hopkins School of Medicine, USA
| | - Ahamed Hossain
- Kennedy Krieger Institute Intellectual and Developmental Disabilities Research Center/Hugo Moser Research Institute at Kennedy Krieger and Johns Hopkins School of Medicine, USA
| | - Shilpa Kadam
- Kennedy Krieger Institute Intellectual and Developmental Disabilities Research Center/Hugo Moser Research Institute at Kennedy Krieger and Johns Hopkins School of Medicine, USA
| | - Xinyu Zhao
- Waisman Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Quiang Chang
- Waisman Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Zhaolan Zhou
- Department of Genetic, Epigenetic Institute, University of Pennsylvania Perelman School of Medicine, Intellectual and Developmental Disabilities Research Center, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Huda Zoghbi
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX, USA
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19
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Neul JL, Skinner SA, Annese F, Lane J, Heydemann P, Jones M, Kaufmann WE, Glaze DG, Percy AK. Metabolic Signatures Differentiate Rett Syndrome From Unaffected Siblings. Front Integr Neurosci 2020; 14:7. [PMID: 32161522 PMCID: PMC7052375 DOI: 10.3389/fnint.2020.00007] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 01/30/2020] [Indexed: 01/07/2023] Open
Abstract
Rett syndrome (RTT, OMIM 312750), a severe neurodevelopmental disorder characterized by regression with loss of spoken language and hand skills, development of characteristic hand stereotypies, and gait dysfunction, is primarily caused by de novo mutations in the X-linked gene Methyl-CpG-binding protein 2 (MECP2). Currently, treatment options are limited to symptomatic management, however, reversal of disease phenotype is possible in mouse models by restoration of normal MECP2 gene expression. A significant challenge is the lack of biomarkers of disease state, disease severity, or treatment response. Using a non-targeted metabolomic approach we evaluated metabolite profiles in plasma from thirty-four people with RTT compared to thirty-seven unaffected age- and gender-matched siblings. We identified sixty-six significantly altered metabolites that cluster broadly into amino acid, nitrogen handling, and exogenous substance pathways. RTT disease metabolite and metabolic pathways abnormalities point to evidence of oxidative stress, mitochondrial dysfunction, and alterations in gut microflora. These observed changes provide insight into underlying pathological mechanisms and the foundation for biomarker discovery of disease severity biomarkers.
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Affiliation(s)
- Jeffrey L Neul
- Vanderbilt University Medical Center, Nashville, TN, United States.,Department of Neurosciences, University of California, San Diego, San Diego, CA, United States.,Baylor College of Medicine, Houston, TX, United States
| | | | - Fran Annese
- Greenwood Genetic Center, Greenwood, SC, United States
| | - Jane Lane
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, United States
| | | | - Mary Jones
- Benioff Children's Hospital Oakland, University of California, San Francisco, San Francisco, CA, United States
| | | | | | - Alan K Percy
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, United States
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Cordone V, Pecorelli A, Amicarelli F, Hayek J, Valacchi G. The complexity of Rett syndrome models: Primary fibroblasts as a disease-in-a-dish reliable approach. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.ddmod.2019.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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21
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Effect of Dietary n-3 Source on Rabbit Male Reproduction. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:3279670. [PMID: 32082475 PMCID: PMC7011472 DOI: 10.1155/2019/3279670] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 11/22/2019] [Accepted: 11/29/2019] [Indexed: 12/30/2022]
Abstract
In the last two decades, the human sperm count linearly decreased in Western countries. Health problems, lifestyle, pollutants, and dietary behaviours are considered as the main risk factors, and the unbalance of dietary n‐6/n‐3 fatty acids is one of the most relevant. The aim of the present research is to study the effect of different dietary sources of n‐3 polyunsaturated fatty acids (PUFA) on reproductive traits using rabbit buck as the animal model. Fifteen rabbit bucks were assigned to three experimental groups: the control group, the FLAX group fed 10% extruded flaxseed, and the FISH group fed 3.5% fish oil for 110 days (50-day adaptation and 60-day experimental periods). Semen samples were collected weekly, whereas blood was collected every two weeks for the analytical determination of semen traits, oxidative status, fatty acid profiles, isoprostanes, neuroprostanes, and the immunocytochemistry of docosahexaenoic acid (DHA) and eicosapentaenoic (EPA) acid. At the end of the trial, the rabbits were killed and the testes were removed and stored for the analysis of fatty acid profile and immunocytochemistry. Results showed that dietary administration of n‐3 PUFA improved the track speed of the sperm and increased the n‐3 long-chain PUFA mainly confined in the sperm tail. Seminal plasma increased the thiobarbituric reactive substances (TBARs) by three times in the groups fed supplemental n‐3, whereas the F2-isoprotanes (F2-IsoPs) and F4-neuroprostanes (F4-NeuroPs) were lower and higher, respectively, in both supplemented groups than in the control. The testes and sperm showed a higher DHA and EPA distribution in rabbits from the n‐3 supplemented groups compared with the control. In conclusion, supplemental dietary n‐3 PUFA improved sperm motion traits and resulted in an enrichment of membrane fatty acid in the sperm and testes of the rabbits. However, such an increased amount of PUFA negatively affected the sperm oxidative status, which was mainly correlated with the generation of F4-NeuroPs with respect to F2-IsoPs. Accordingly, the latter cannot be considered a good marker of oxidation when diets rich in n‐3 PUFA are provided.
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22
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Effects of oral administration of common antioxidant supplements on the energy metabolism of red blood cells. Attenuation of oxidative stress-induced changes in Rett syndrome erythrocytes by CoQ10. Mol Cell Biochem 2019; 463:101-113. [PMID: 31595423 DOI: 10.1007/s11010-019-03633-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 09/25/2019] [Indexed: 01/15/2023]
Abstract
Nutritional supplements are traditionally employed for overall health and for managing some health conditions, although controversies are found concerning the role of antioxidants-mediated benefits in vivo. Consistently with its critical role in systemic redox buffering, red blood cell (RBC) is recognized as a biologically relevant target to investigate the effects of oxidative stress. In RBC, reduction of the ATP levels and adenylate energy charge brings to disturbance in intracellular redox status. In the present work, several popular antioxidant supplements were orally administrated to healthy adults and examined for their ability to induce changes on the energy metabolism and oxidative status in RBC. Fifteen volunteers (3 per group) were treated for 30 days per os with epigallocatechin gallate (EGCG) (1 g green tea extract containing 50% EGCG), resveratrol (325 mg), coenzyme Q10 (CoQ10) (300 mg), vitamin C (1 g), and vitamin E (400 U.I.). Changes in the cellular levels of high-energy compounds (i.e., ATP and its catabolites, NAD and GTP), GSH, GSSG, and malondialdehyde (MDA) were simultaneously analyzed by ion-pairing HPLC. Response to oxidative stress was further investigated through the oxygen radical absorptive capacity (ORAC) assay. According to our experimental approach, (i) CoQ10 appeared to be the most effective antioxidant inducing a high increase in ATP/ADP, ATP/AMP, GSH/GSSG ratio and ORAC value and, in turn, a reduction of NAD concentration, (ii) EGCG modestly modulated the intracellular energy charge potential, while (iii) Vitamin E, vitamin C, and resveratrol exhibited very weak effects. Given that, the antioxidant potential of CoQ10 was additionally assessed in a pilot study which considered individuals suffering from Rett syndrome (RTT), a severe X-linked neuro-developmental disorder in which RBC oxidative damages provide biological markers for redox imbalance and chronic hypoxemia. RTT patients (n = 11), with the typical clinical form, were supplemented for 12 months with CoQ10 (300 mg, once daily). Level of lipid peroxidation (MDA production) and energy state of RBCs were analyzed at 2 and 12 months. Our data suggest that CoQ10 may significantly attenuate the oxidative stress-induced damage in RTT erythrocytes.
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23
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Mouro FM, Miranda-Lourenço C, Sebastião AM, Diógenes MJ. From Cannabinoids and Neurosteroids to Statins and the Ketogenic Diet: New Therapeutic Avenues in Rett Syndrome? Front Neurosci 2019; 13:680. [PMID: 31333401 PMCID: PMC6614559 DOI: 10.3389/fnins.2019.00680] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 06/13/2019] [Indexed: 12/21/2022] Open
Abstract
Rett syndrome (RTT) is an X-linked neurodevelopmental disorder caused mainly by mutations in the MECP2 gene, being one of the leading causes of mental disability in females. Mutations in the MECP2 gene are responsible for 95% of the diagnosed RTT cases and the mechanisms through which these mutations relate with symptomatology are still elusive. Children with RTT present a period of apparent normal development followed by a rapid regression in speech and behavior and a progressive deterioration of motor abilities. Epilepsy is one of the most common symptoms in RTT, occurring in 60 to 80% of RTT cases, being associated with worsening of other symptoms. At this point, no cure for RTT is available and there is a pressing need for the discovery of new drug candidates to treat its severe symptoms. However, despite being a rare disease, in the last decade research in RTT has grown exponentially. New and exciting evidence has been gathered and the etiopathogenesis of this complex, severe and untreatable disease is slowly being unfolded. Advances in gene editing techniques have prompted cure-oriented research in RTT. Nonetheless, at this point, finding a cure is a distant reality, highlighting the importance of further investigating the basic pathological mechanisms of this disease. In this review, we focus our attention in some of the newest evidence on RTT clinical and preclinical research, evaluating their impact in RTT symptomatology control, and pinpointing possible directions for future research.
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Affiliation(s)
- Francisco Melo Mouro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Catarina Miranda-Lourenço
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Ana Maria Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Maria José Diógenes
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
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Can K, Menzfeld C, Rinne L, Rehling P, Kügler S, Golubiani G, Dudek J, Müller M. Neuronal Redox-Imbalance in Rett Syndrome Affects Mitochondria as Well as Cytosol, and Is Accompanied by Intensified Mitochondrial O 2 Consumption and ROS Release. Front Physiol 2019; 10:479. [PMID: 31114506 PMCID: PMC6503037 DOI: 10.3389/fphys.2019.00479] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 04/05/2019] [Indexed: 12/31/2022] Open
Abstract
Rett syndrome (RTT), an X chromosome-linked neurodevelopmental disorder affecting almost exclusively females, is associated with various mitochondrial alterations. Mitochondria are swollen, show altered respiratory rates, and their inner membrane is leaking protons. To advance the understanding of these disturbances and clarify their link to redox impairment and oxidative stress, we assessed mitochondrial respiration in defined brain regions and cardiac tissue of male wildtype (WT) and MeCP2-deficient (Mecp2-/y ) mice. Also, we quantified for the first time neuronal redox-balance with subcellular resolution in cytosol and mitochondrial matrix. Quantitative roGFP1 redox imaging revealed more oxidized conditions in the cytosol of Mecp2-/y hippocampal neurons than in WT neurons. Furthermore, cytosol and mitochondria of Mecp2-/y neurons showed exaggerated redox-responses to hypoxia and cell-endogenous reactive oxygen species (ROS) formation. Biochemical analyzes exclude disease-related increases in mitochondrial mass in Mecp2-/y hippocampus and cortex. Protein levels of complex I core constituents were slightly lower in Mecp2-/y hippocampus and cortex than in WT; those of complex V were lower in Mecp2-/y cortex. Respiratory supercomplex-formation did not differ among genotypes. Yet, supplied with the complex II substrate succinate, mitochondria of Mecp2-/y cortex and hippocampus consumed more O2 than WT. Furthermore, mitochondria from Mecp2-/y hippocampus and cortex mediated an enhanced oxidative burden. In conclusion, we further advanced the molecular understanding of mitochondrial dysfunction in RTT. Intensified mitochondrial O2 consumption, increased mitochondrial ROS generation and disturbed redox balance in mitochondria and cytosol may represent a causal chain, which provokes dysregulated proteins, oxidative tissue damage, and contributes to neuronal network dysfunction in RTT.
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Affiliation(s)
- Karolina Can
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Georg-August-University Göttingen, Göttingen, Germany
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Christiane Menzfeld
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Georg-August-University Göttingen, Göttingen, Germany
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Lena Rinne
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Peter Rehling
- Zentrum Biochemie und Molekulare Zellbiologie, Institut für Zellbiochemie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Sebastian Kügler
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Georg-August-University Göttingen, Göttingen, Germany
- Klinik für Neurologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Gocha Golubiani
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
- Institute of Chemical Biology, Ilia State University, Tbilisi, Georgia
| | - Jan Dudek
- Zentrum Biochemie und Molekulare Zellbiologie, Institut für Zellbiochemie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Michael Müller
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Georg-August-University Göttingen, Göttingen, Germany
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Germany
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25
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Müller M. Disturbed redox homeostasis and oxidative stress: Potential players in the developmental regression in Rett syndrome. Neurosci Biobehav Rev 2019; 98:154-163. [PMID: 30639673 DOI: 10.1016/j.neubiorev.2018.12.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/30/2018] [Accepted: 12/06/2018] [Indexed: 12/16/2022]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder affecting mostly girls. A seemingly normal initial development is followed by developmental stagnation and regression, leading to severe mental impairment with autistic features, motor dysfunction, irregular breathing and epilepsy. Currently, a cure does not exist. Due to the close association of RTT with mitochondrial alterations, cellular redox-impairment and oxidative stress, compounds stabilizing mitochondrial function, cellular redox-homeostasis, and oxidant detoxification are increasingly considered as treatment concepts. Indeed, antioxidants and free-radical scavengers ameliorate certain aspects of the complex and severe clinical presentation of RTT. To further evaluate these strategies, reliable biosensors are needed to quantify redox-conditions in brain and peripheral organs of mouse models or in patient-derived cells. Genetically-encoded redox-sensors meet these requirements. Expressed in transgenic mouse-models such as our unique Rett-redox indicator mice, they will report for any cell type desired the severity of oxidant stress throughout the various disease stages of RTT. Furthermore, these sensors will be crucial to evaluate in vitro and in vivo the outcome of mitochondria- and redox-balance targeted treatments.
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Affiliation(s)
- Michael Müller
- Georg-August-Universität Göttingen, Universitätsmedizin Göttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Humboldtallee 23, D-37073 Göttingen, Germany; Zentrum Physiologie und Pathophysiologie, Institut für Neuro-und Sinnesphysiologie, Humboldtallee 23, D-37073 Göttingen, Germany.
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26
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Vogel Ciernia A, Yasui DH, Pride MC, Durbin-Johnson B, Noronha AB, Chang A, Knotts TA, Rutkowsky JR, Ramsey JJ, Crawley JN, LaSalle JM. MeCP2 isoform e1 mutant mice recapitulate motor and metabolic phenotypes of Rett syndrome. Hum Mol Genet 2018; 27:4077-4093. [PMID: 30137367 PMCID: PMC6240741 DOI: 10.1093/hmg/ddy301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/10/2018] [Accepted: 08/14/2018] [Indexed: 01/27/2023] Open
Abstract
Mutations in the X-linked gene MECP2 cause the majority of Rett syndrome (RTT) cases. Two differentially spliced isoforms of exons 1 and 2 (MeCP2-e1 and MeCP2-e2) contribute to the diverse functions of MeCP2, but only mutations in exon 1, not exon 2, are observed in RTT. We previously described an isoform-specific MeCP2-e1-deficient male mouse model of a human RTT mutation that lacks MeCP2-e1 while preserving expression of MeCP2-e2. However, RTT patients are heterozygous females that exhibit delayed and progressive symptom onset beginning in late infancy, including neurologic as well as metabolic, immune, respiratory and gastrointestinal phenotypes. Consequently, we conducted a longitudinal assessment of symptom development in MeCP2-e1 mutant females and males. A delayed and progressive onset of motor impairments was observed in both female and male MeCP2-e1 mutant mice, including hind limb clasping and motor deficits in gait and balance. Because these motor impairments were significantly impacted by age-dependent increases in body weight, we also investigated metabolic phenotypes at an early stage of disease progression. Both male and female MeCP2-e1 mutants exhibited significantly increased body fat compared to sex-matched wild-type littermates prior to weight differences. Mecp2e1-/y males exhibited significant metabolic phenotypes of hypoactivity, decreased energy expenditure, increased respiratory exchange ratio, but decreased food intake compared to wild-type. Untargeted analysis of lipid metabolites demonstrated a distinguishable profile in MeCP2-e1 female mutant liver characterized by increased triglycerides. Together, these results demonstrate that MeCP2-e1 mutation in mice of both sexes recapitulates early and progressive metabolic and motor phenotypes of human RTT.
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Affiliation(s)
- Annie Vogel Ciernia
- Department of Medical Microbiology and Immunology, UC Davis School of Medicine, University of California, Davis, CA, USA
- UC Davis Genome Center, University of California, Davis, CA, USA
- UC Davis MIND Institute, University of California, Davis, CA, USA
| | - Dag H Yasui
- Department of Medical Microbiology and Immunology, UC Davis School of Medicine, University of California, Davis, CA, USA
| | - Michael C Pride
- UC Davis MIND Institute, University of California, Davis, CA, USA
- Department of Psychiatry and Behavioral Sciences, UC Davis School of Medicine, University of California, Davis, CA, USA
| | - Blythe Durbin-Johnson
- Department of Public Health Sciences, UC Davis School of Medicine, University of California, Davis, CA, USA
| | - Adriana B Noronha
- Department of Medical Microbiology and Immunology, UC Davis School of Medicine, University of California, Davis, CA, USA
| | - Alene Chang
- Department of Medical Microbiology and Immunology, UC Davis School of Medicine, University of California, Davis, CA, USA
| | - Trina A Knotts
- Department of Molecular Biosciences, UC Davis School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Jennifer R Rutkowsky
- Department of Molecular Biosciences, UC Davis School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Jon J Ramsey
- Department of Molecular Biosciences, UC Davis School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Jacqueline N Crawley
- UC Davis MIND Institute, University of California, Davis, CA, USA
- Department of Psychiatry and Behavioral Sciences, UC Davis School of Medicine, University of California, Davis, CA, USA
| | - Janine M LaSalle
- Department of Medical Microbiology and Immunology, UC Davis School of Medicine, University of California, Davis, CA, USA
- UC Davis Genome Center, University of California, Davis, CA, USA
- UC Davis MIND Institute, University of California, Davis, CA, USA
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27
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Ramirez JM, Severs LJ, Ramirez SC, Agosto‐Marlin IM. Advances in cellular and integrative control of oxygen homeostasis within the central nervous system. J Physiol 2018; 596:3043-3065. [PMID: 29742297 PMCID: PMC6068258 DOI: 10.1113/jp275890] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 04/04/2018] [Indexed: 12/31/2022] Open
Abstract
Mammals must continuously regulate the levels of O2 and CO2 , which is particularly important for the brain. Failure to maintain adequate O2 /CO2 homeostasis has been associated with numerous disorders including sleep apnoea, Rett syndrome and sudden infant death syndrome. But, O2 /CO2 homeostasis poses major regulatory challenges, even in the healthy brain. Neuronal activities change in a differentiated, spatially and temporally complex manner, which is reflected in equally complex changes in O2 demand. This raises important questions: is oxygen sensing an emergent property, locally generated within all active neuronal networks, and/or the property of specialized O2 -sensitive CNS regions? Increasing evidence suggests that the regulation of the brain's redox state involves properties that are intrinsic to many networks, but that specialized regions in the brainstem orchestrate the integrated control of respiratory and cardiovascular functions. Although the levels of O2 in arterial blood and the CNS are very different, neuro-glial interactions and purinergic signalling are critical for both peripheral and CNS chemosensation. Indeed, the specificity of neuroglial interactions seems to determine the differential responses to O2 , CO2 and the changes in pH.
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Affiliation(s)
- Jan Marino Ramirez
- Center for Integrative Brain ResearchSeattle Children's Research InstituteDepartment of Neurological SurgeryUniversity of Washington School of MedicineSeattleWAUSA
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | - Liza J. Severs
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | - Sanja C. Ramirez
- Center for Integrative Brain ResearchSeattle Children's Research InstituteDepartment of Neurological SurgeryUniversity of Washington School of MedicineSeattleWAUSA
| | - Ibis M. Agosto‐Marlin
- Center for Integrative Brain ResearchSeattle Children's Research InstituteDepartment of Neurological SurgeryUniversity of Washington School of MedicineSeattleWAUSA
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28
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Signorini C, De Felice C, Durand T, Galano JM, Oger C, Leoncini S, Ciccoli L, Carone M, Ulivelli M, Manna C, Cortelazzo A, Lee JCY, Hayek J. Relevance of 4-F 4t-neuroprostane and 10-F 4t-neuroprostane to neurological diseases. Free Radic Biol Med 2018; 115:278-287. [PMID: 29233794 DOI: 10.1016/j.freeradbiomed.2017.12.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/16/2017] [Accepted: 12/06/2017] [Indexed: 12/11/2022]
Abstract
F4-neuroprostanes (F4-NeuroPs) are non-enzymatic oxidized products derived from docosahexaenoic acid (DHA) and are suggested to be oxidative damage biomarkers of neurological diseases. However, 128 isomers can be formed from DHA oxidation and among them, 4(RS)-4-F4t-NeuroP (4-F4t-NeuroP) and 10(RS)-10-F4t-NeuroP (10-F4t-NeuroP) are the most studied. Here, we report the identification and the clinical relevance of 4-F4t-NeuroP and 10-F4t-NeuroP in plasma of four different neurological diseases, including multiple sclerosis (MS), autism spectrum disorders (ASD), Rett syndrome (RTT), and Down syndrome (DS). The identification and the optimization of the method were carried out by gas chromatography/negative-ion chemical ionization tandem mass spectrometry (GC/NICI-MS/MS) using chemically synthesized 4-F4t-NeuroP and 10-F4t-NeuroP standards and in oxidized DHA liposome. Both 4-F4t-NeuroP and 10-F4t-NeuroP were detectable in all plasma samples from MS (n = 16), DS (n = 16), ASD (n = 9) and RTT (n = 20) patients. While plasma 10-F4t-NeuroP content was significantly higher in patients of all diseases as compared to age and gender matched healthy control subjects (n = 61), 4-F4t-NeuroP levels were significantly higher in MS and RTT as compared to healthy controls. Significant positive relationships were observed between relative disease severity and 4-F4t-NeuroP levels (r = 0.469, P <0.0001), and 10-F4t-NeuroP levels (r = 0.757, P < 0.0001). The study showed that the plasma amount ratio of 10-F4t-NeuroP to 4-F4t-NeuroP and the plasma amount as individual isomer can be used to discriminate between different brain diseases. Overall, by comparing the different types of disease, our plasma data indicates that 4-F4t-NeuroP and 10-F4t -NeuroP: i) are biologically synthesized in vivo and circulated, ii) are related to clinical severity of neurological diseases, iii) are useful to identify shared pathogenetic pathways in distinct brain diseases, and iv) appears to be distinctive for different neurological conditions, thus representing potentially new biological disease markers. Our data strongly suggest that in vivo DHA oxidation follows preferential chemical rearrangements according to different brain diseases.
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Affiliation(s)
- Cinzia Signorini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Claudio De Felice
- Neonatal Intensive Care Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Montpellier, France
| | - Jean-Marie Galano
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Montpellier, France
| | - Camille Oger
- Institut des Biomolécules Max Mousseron, (IBMM), UMR 5247, CNRS, Université de Montpellier, ENSCM, Montpellier, France
| | - Silvia Leoncini
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Lucia Ciccoli
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Marisa Carone
- Department of Medicine, Surgery, and Neuroscience, University of Siena, Siena, Italy
| | - Monica Ulivelli
- Department of Medicine, Surgery, and Neuroscience, University of Siena, Siena, Italy
| | - Caterina Manna
- Department of Biochemistry, Biophysics and General Pathology, University of Campania "Luigi Vanvitelli", Naples, Italy"
| | - Alessio Cortelazzo
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy; Clinical Pathology Laboratory Unit, University Hospital, AOUS, Siena, Italy
| | - Jetty Chung-Yung Lee
- The University of Hong Kong, School of Biological Sciences, Hong Kong Special Administrative Region
| | - Joussef Hayek
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
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Valacchi G, Pecorelli A, Cervellati C, Hayek J. 4-hydroxynonenal protein adducts: Key mediator in Rett syndrome oxinflammation. Free Radic Biol Med 2017; 111:270-280. [PMID: 28063942 DOI: 10.1016/j.freeradbiomed.2016.12.045] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 12/24/2016] [Accepted: 12/30/2016] [Indexed: 12/13/2022]
Abstract
In the last 15 years a strong correlation between oxidative stress (OxS) and Rett syndrome (RTT), a rare neurodevelopmental disorder known to be caused in 95% of the cases, by a mutation in the methyl-CpG-binding protein 2 (MECP2) gene, has been well documented. Here, we revised, summarized and discussed the current knowledge on the role of lipid peroxidation byproducts, with special emphasis on 4-hydroxynonenal (4HNE), in RTT pathophysiology. The posttranslational modifications of proteins via 4HNE, known as 4HNE protein adducts (4NHE-PAs), causing detrimental effects on protein functions, appear to contribute to the clinical severity of the syndrome, since their levels increase significantly during the subsequent 4 clinical stages, reaching the maximum degree at stage 4, represented by a late motor deterioration. In addition, 4HNE-PA are only partially removed due to the compromised functionality of the proteasome activity, contributing therefore to the cellular damage in RTT. All this will lead to a characteristic subclinical inflammation, defined "OxInflammation", derived by a positive feedback loop between OxS byproducts and inflammatory mediators that in a long run further aggravates the clinical features of RTT patients. Therefore, in a pathology completely orphan of any therapy, aiming 4HNE as a therapeutic target could represent a coadjuvant treatment with some beneficial impact in these patients..
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Affiliation(s)
- Giuseppe Valacchi
- Plants for Human Health Institute, Department of Animal Sciences, NC State University, NC Research Campus, 600 Laureate Way, Kannapolis, NC 28081, USA; Department of Life Sciences and Biotechnology, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy.
| | - Alessandra Pecorelli
- Plants for Human Health Institute, Department of Animal Sciences, NC State University, NC Research Campus, 600 Laureate Way, Kannapolis, NC 28081, USA; Department of Life Sciences and Biotechnology, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
| | - Carlo Cervellati
- Department of Biomedical and Specialist Surgical Sciences, Section of Medical Biochemistry, Molecular Biology and Genetics, University of Ferrara, Via Luigi Borsari 46, 44121 Ferrara, Italy
| | - Joussef Hayek
- Child Neuropsychiatry Unit, University Hospital, AOUS, Viale Mario Bracci, 53100 Siena, Italy
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Pathogenesis of Lethal Aspiration Pneumonia in Mecp2-null Mouse Model for Rett Syndrome. Sci Rep 2017; 7:12032. [PMID: 28931890 PMCID: PMC5607245 DOI: 10.1038/s41598-017-12293-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 09/06/2017] [Indexed: 11/09/2022] Open
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder mainly caused by mutations in the gene encoding the transcriptional regulator Methyl-CpG-binding protein 2 (MeCP2), located on the X chromosome. Many RTT patients have breathing abnormalities, such as apnea and breathing irregularity, and respiratory infection is the most common cause of death in these individuals. Previous studies showed that MeCP2 is highly expressed in the lung, but its role in pulmonary function remains unknown. In this study, we found that MeCP2 deficiency affects pulmonary gene expression and structures. We also found that Mecp2-null mice, which also have breathing problems, often exhibit inflammatory lung injury. These injuries occurred in specific sites in the lung lobes. In addition, polarizable foreign materials were identified in the injured lungs of Mecp2-null mice. These results indicated that aspiration might be a cause of inflammatory lung injury in Mecp2-null mice. On the other hand, MeCP2 deficiency affected the expression of several neuromodulator genes in the lower brainstem. Among them, neuropeptide substance P (SP) immunostaining was reduced in Mecp2-null brainstem. These findings suggest that alteration of SP expression in brainstem may be involved in autonomic dysregulation, and may be one of the causes of aspiration in Mecp2-null mice.
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Increased Mitochondrial Mass and Cytosolic Redox Imbalance in Hippocampal Astrocytes of a Mouse Model of Rett Syndrome: Subcellular Changes Revealed by Ratiometric Imaging of JC-1 and roGFP1 Fluorescence. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:3064016. [PMID: 28894505 PMCID: PMC5574314 DOI: 10.1155/2017/3064016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 06/16/2017] [Accepted: 06/27/2017] [Indexed: 12/21/2022]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder with mutations in the MECP2 gene. Mostly girls are affected, and an apparently normal development is followed by cognitive impairment, motor dysfunction, epilepsy, and irregular breathing. Various indications suggest mitochondrial dysfunction. In Rett mice, brain ATP levels are reduced, mitochondria are leaking protons, and respiratory complexes are dysregulated. Furthermore, we found in MeCP2-deficient mouse (Mecp2−/y) hippocampus an intensified mitochondrial metabolism and ROS generation. We now used emission ratiometric 2-photon imaging to assess mitochondrial morphology, mass, and membrane potential (ΔΨm) in Mecp2−/y hippocampal astrocytes. Cultured astrocytes were labeled with the ΔΨm marker JC-1, and semiautomated analyses yielded the number of mitochondria per cell, their morphology, and ΔΨm. Mecp2−/y astrocytes contained more mitochondria than wild-type (WT) cells and were more oxidized. Mitochondrial size, ΔΨm, and vulnerability to pharmacological challenge did not differ. The antioxidant Trolox opposed the oxidative burden and decreased the mitochondrial mass, thereby dampening the differences among WT and Mecp2−/y astrocytes; mitochondrial size and ΔΨm were not markedly affected. In conclusion, mitochondrial alterations and redox imbalance in RTT also involve astrocytes. Mitochondria are more numerous in Mecp2−/y than in WT astrocytes. As this genotypic difference is abolished by Trolox, it seems linked to the oxidative stress in RTT.
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Persistent Unresolved Inflammation in the Mecp2-308 Female Mutated Mouse Model of Rett Syndrome. Mediators Inflamm 2017; 2017:9467819. [PMID: 28592917 PMCID: PMC5448068 DOI: 10.1155/2017/9467819] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 04/19/2017] [Indexed: 12/27/2022] Open
Abstract
Rett syndrome (RTT) is a rare neurodevelopmental disorder usually caused by mutations in the X-linked gene methyl-CpG-binding protein 2 (MECP2). Several Mecp2 mutant mouse lines have been developed recapitulating part of the clinical features. In particular, Mecp2-308 female heterozygous mice, bearing a truncating mutation, are a validated model of the disease. While recent data suggest a role for inflammation in RTT, little information on the inflammatory status in murine models of the disease is available. Here, we investigated the inflammatory status by proteomic 2-DE/MALDI-ToF/ToF analyses in symptomatic Mecp2-308 female mice. Ten differentially expressed proteins were evidenced in the Mecp2-308 mutated plasma proteome. In particular, 5 positive acute-phase response (APR) proteins increased (i.e., kininogen-1, alpha-fetoprotein, mannose-binding protein C, alpha-1-antitrypsin, and alpha-2-macroglobulin), and 3 negative APR reactants were decreased (i.e., serotransferrin, albumin, and apolipoprotein A1). CD5 antigen-like and vitamin D-binding protein, two proteins strictly related to inflammation, were also changed. These results indicate for the first time a persistent unresolved inflammation of unknown origin in the Mecp2-308 mouse model.
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Demion M, Oger C, Vigor C, Thireau J, Guennec JYL, Durand T, Galano JM, Lee JCY. Two sides of the same coin: NEO-PUFAs in Rett syndrome and post-infarction cardiac arrhythmias. EUR J LIPID SCI TECH 2017. [DOI: 10.1002/ejlt.201600320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marie Demion
- Inserm U1046-UMR CNRS 9214 Physiologie et Médecine Expérimentale du cœur et des muscles−PHYMEDEX; Université de Montpellier; Montpellier France
| | - Camille Oger
- Institut des Biomolécules Max Mousseron, (IBMM) UMR 5247; CNRS Université de Montpellier, ENSCM; Montpellier France
| | - Claire Vigor
- Institut des Biomolécules Max Mousseron, (IBMM) UMR 5247; CNRS Université de Montpellier, ENSCM; Montpellier France
| | - Jérôme Thireau
- Inserm U1046-UMR CNRS 9214 Physiologie et Médecine Expérimentale du cœur et des muscles−PHYMEDEX; Université de Montpellier; Montpellier France
| | - Jean-Yves Le Guennec
- Inserm U1046-UMR CNRS 9214 Physiologie et Médecine Expérimentale du cœur et des muscles−PHYMEDEX; Université de Montpellier; Montpellier France
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron, (IBMM) UMR 5247; CNRS Université de Montpellier, ENSCM; Montpellier France
| | - Jean-Marie Galano
- Institut des Biomolécules Max Mousseron, (IBMM) UMR 5247; CNRS Université de Montpellier, ENSCM; Montpellier France
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Cortelazzo A, Pietri T, De Felice C, Leoncini S, Guerranti R, Signorini C, Timperio AM, Zolla L, Ciccoli L, Hayek J. Proteomic analysis of the Rett syndrome experimental model mecp2 Q63X mutant zebrafish. J Proteomics 2017; 154:128-133. [PMID: 28062374 DOI: 10.1016/j.jprot.2016.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 12/09/2016] [Accepted: 12/20/2016] [Indexed: 11/29/2022]
Abstract
Rett syndrome (RTT) is a severe genetic disorder resulting from mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene. Recently, a zebrafish carrying a mecp2-null mutation has been developed with the resulting phenotypes exhibiting defective sensory and thigmotactic responses, and abnormal motor behavior reminiscent of the human disease. Here, we performed a proteomic analysis to examine protein expression changes in mecp2-null vs. wild-type larvae and adult zebrafish. We found a total of 20 proteins differentially expressed between wild-type and mutant zebrafish, suggesting skeletal and cardiac muscle functional defects, a stunted glycolysis and depleted energy availability. This molecular evidence is directly linked to the mecp2-null zebrafish observed phenotype. In addition, we identified changes in expression of proteins critical for a proper redox balance, suggesting an enhanced oxidative stress, a phenomenon also documented in human patients and RTT murine models. The molecular alterations observed in the mecp2-null zebrafish expand our knowledge on the molecular cascade of events that lead to the RTT phenotype. BIOLOGICAL SIGNIFICANCE We performed a proteomic study of a non-mammalian vertebrate model (zebrafish, Danio rerio) for Rett syndrome (RTT) at larval and adult stages of development. Our results reveal major protein expression changes pointing out to defects in energy metabolism, redox status imbalance, and muscle function, both skeletal and cardiac. Our molecular analysis grants the mecp2-null zebrafish as a valuable RTT model, triggering new research approaches for a better understanding of the RTT pathogenesis and phenotype expression. This non-mammalian vertebrate model of RTT strongly suggests a broad impact of Mecp2 dysfunction.
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Affiliation(s)
- Alessio Cortelazzo
- Child Neuropsychiatry Unit, University Hospital, Azienda Ospedaliera Universitaria Senese (AOUS), Siena, Italy; Department of Medical Biotechnologies, University of Siena, Siena, Italy; Clinical Pathology Laboratory Unit, University Hospital, AOUS, Siena, Italy.
| | - Thomas Pietri
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, Paris, France
| | - Claudio De Felice
- Neonatal Intensive Care Unit, University Hospital, AOUS, Siena, Italy
| | - Silvia Leoncini
- Child Neuropsychiatry Unit, University Hospital, Azienda Ospedaliera Universitaria Senese (AOUS), Siena, Italy; Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Roberto Guerranti
- Department of Medical Biotechnologies, University of Siena, Siena, Italy; Clinical Pathology Laboratory Unit, University Hospital, AOUS, Siena, Italy
| | - Cinzia Signorini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Anna Maria Timperio
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Lello Zolla
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Lucia Ciccoli
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Joussef Hayek
- Child Neuropsychiatry Unit, University Hospital, Azienda Ospedaliera Universitaria Senese (AOUS), Siena, Italy
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Pecorelli A, Cervellati C, Hayek J, Valacchi G. OxInflammation in Rett syndrome. Int J Biochem Cell Biol 2016; 81:246-253. [DOI: 10.1016/j.biocel.2016.07.015] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 07/11/2016] [Accepted: 07/14/2016] [Indexed: 12/24/2022]
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Janc OA, Hüser MA, Dietrich K, Kempkes B, Menzfeld C, Hülsmann S, Müller M. Systemic Radical Scavenger Treatment of a Mouse Model of Rett Syndrome: Merits and Limitations of the Vitamin E Derivative Trolox. Front Cell Neurosci 2016; 10:266. [PMID: 27895554 PMCID: PMC5109403 DOI: 10.3389/fncel.2016.00266] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 11/01/2016] [Indexed: 12/21/2022] Open
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder typically arising from spontaneous mutations in the X-chromosomal methyl-CpG binding protein 2 (MECP2) gene. The almost exclusively female Rett patients show an apparently normal development during their first 6-18 months of life. Subsequently, cognitive- and motor-impairment, hand stereotypies, loss of learned skills, epilepsy and irregular breathing manifest. Early mitochondrial impairment and oxidative challenge are considered to facilitate disease progression. Along this line, we recently confirmed in vitro that acute treatment with the vitamin E-derivative Trolox dampens neuronal hyperexcitability, reinstates synaptic plasticity, ameliorates cellular redox balance and improves hypoxia tolerance in male MeCP2-deficient (Mecp2-/y ) mouse hippocampus. Pursuing these promising findings, we performed a preclinical study to define the merit of systemic Trolox administration. Blinded, placebo-controlled in vivo treatment of male mice started at postnatal day (PD) 10-11 and continued for ~40 days. Compounds (vehicle only, 10 mg/kg or 40 mg/kg Trolox) were injected intraperitoneally every 48 h. Detailed phenotyping revealed that in Mecp2-/y mice, blood glucose levels, lipid peroxidation, synaptic short-term plasticity, hypoxia tolerance and certain forms of environmental exploration were improved by Trolox. Yet, body weight and size, motor function and the rate and regularity of breathing did not improve. In conclusion, in vivo Trolox treatment partially ameliorated a subset of symptoms of the complex Rett phenotype, thereby confirming a partial merit of the vitamin E-derivative based pharmacotherapy. Yet, it also became evident that frequent animal handling and the route of drug administration are critical issues to be optimized in future trials.
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Affiliation(s)
- Oliwia A Janc
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany; Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-UniversitätGöttingen, Germany
| | - Marc A Hüser
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Germany
| | - Katharina Dietrich
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany; Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-UniversitätGöttingen, Germany
| | - Belinda Kempkes
- Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Germany
| | - Christiane Menzfeld
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany; Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-UniversitätGöttingen, Germany
| | - Swen Hülsmann
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany; Klinik für Anästhesiologie, Universitätsmedizin Göttingen, Georg-August-UniversitätGöttingen, Germany
| | - Michael Müller
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB)Göttingen, Germany; Zentrum Physiologie und Pathophysiologie, Institut für Neuro- und Sinnesphysiologie, Universitätsmedizin Göttingen, Georg-August-UniversitätGöttingen, Germany
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Hülsmann S, Mesuret G, Dannenberg J, Arnoldt M, Niebert M. GlyT2-Dependent Preservation of MECP2-Expression in Inhibitory Neurons Improves Early Respiratory Symptoms but Does Not Rescue Survival in a Mouse Model of Rett Syndrome. Front Physiol 2016; 7:385. [PMID: 27672368 PMCID: PMC5018520 DOI: 10.3389/fphys.2016.00385] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/22/2016] [Indexed: 11/25/2022] Open
Abstract
Mutations in methyl-CpG-binding protein 2 (MECP2) gene have been shown to manifest in a neurodevelopmental disorder that is called Rett syndrome. A typical problem that occurs during development is a disturbance of breathing. To address the role of inhibitory neurons, we generated a mouse line that restores MECP2 in inhibitory neurons in the brainstem by crossbreeding a mouse line that expresses the Cre-recombinase (Cre) in inhibitory neurons under the control of the glycine transporter 2 (GlyT2, slc6a5) promotor (GlyT2-Cre) with a mouse line that has a floxed-stop mutation of the Mecp2 gene (Mecp2stop/y). Unrestrained whole-body-plethysmography at postnatal day P60 revealed a low respiratory rate and prolonged respiratory pauses in Mecp2stop/y mice. In contrast, GlyT2-Cre positive Mecp2stop/y mice (Cre+; Mecp2stop/y) showed greatly improved respiration and were indistinguishable from wild type littermates. These data support the concept that alterations in inhibitory neurons are important for the development of the respiratory phenotype in Rett syndrome.
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Affiliation(s)
- Swen Hülsmann
- Clinic for Anesthesiology, University Medical CenterGöttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the BrainGöttingen, Germany
| | - Guillaume Mesuret
- Clinic for Anesthesiology, University Medical CenterGöttingen, Germany; Center for Nanoscale Microscopy and Molecular Physiology of the BrainGöttingen, Germany
| | - Julia Dannenberg
- Clinic for Anesthesiology, University Medical Center Göttingen, Germany
| | - Mauricio Arnoldt
- Clinic for Anesthesiology, University Medical Center Göttingen, Germany
| | - Marcus Niebert
- Center for Nanoscale Microscopy and Molecular Physiology of the BrainGöttingen, Germany; Institute of Neuro- and Sensory Physiology, University Medical Center GöttingenGöttingen, Germany
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Ciccoli L, De Felice C, Leoncini S, Signorini C, Cortelazzo A, Zollo G, Pecorelli A, Rossi M, Hayek J. Red blood cells in Rett syndrome: oxidative stress, morphological changes and altered membrane organization. Biol Chem 2016; 396:1233-40. [PMID: 26040005 DOI: 10.1515/hsz-2015-0117] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 05/07/2015] [Indexed: 11/15/2022]
Abstract
In this review, we summarize the current evidence on the erythrocyte as a previously unrecognized target cell in Rett syndrome, a rare (1:10 000 females) and devastating neurodevelopmental disorder caused by loss-of-function mutations in a single gene (i.e. MeCP2, CDKL5, or rarely FOXG1). In particular, we focus on morphological changes, membrane oxidative damage, altered membrane fatty acid profile, and aberrant skeletal organization in erythrocytes from patients with typical Rett syndrome and MeCP2 gene mutations. The beneficial effects of ω-3 polyunsaturated fatty acids (PUFAs) are also summarized for this condition to be considered as a 'model' condition for autism spectrum disorders.
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Pecorelli A, Cervellati C, Cortelazzo A, Cervellati F, Sticozzi C, Mirasole C, Guerranti R, Trentini A, Zolla L, Savelli V, Hayek J, Valacchi G. Proteomic analysis of 4-hydroxynonenal and nitrotyrosine modified proteins in RTT fibroblasts. Int J Biochem Cell Biol 2016; 81:236-245. [PMID: 27495376 DOI: 10.1016/j.biocel.2016.08.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 07/27/2016] [Accepted: 08/01/2016] [Indexed: 11/19/2022]
Abstract
Rett syndrome (RTT) is a pervasive developmental disorder, primarily affecting girls with a prevalence of 1 in every 10,000 births. A clear etiological factor present in more than 90% of classical RTT cases is the mutation of the gene encoding methyl-CpG-binding protein 2 (MECP2). Recent work from our group was able to shown a systemic oxidative stress (OxS) in these patients that correlates with the gravity of the clinical features. Using freshly isolated skin fibroblasts from RTT patients and healthy subjects, we have performed a two-dimensional gel electrophoresis in order to evidence the oxidative modifications of proteins with special focus on the formation of protein adducts with 4-hydroxynonenal (4-HNE PAs)-a major secondary product of lipid peroxidation- and Nitrotyrosine, a marker derived from the biochemical interaction of nitric oxide (NO) or nitric oxide-derived secondary products with reactive oxygen species (ROS). Then, oxidatively modified spots were identified by mass spectrometry, LC-ESI-CID-MS/MS. Our results showed that 15 protein spots presented 4-HNE PAs and/or nitrotyrosine adducts in fibroblasts proteome from RTT patients compared to healthy control cells. Post-translationally modified proteins were related to several functional categories, in particular to cytoskeleton structure and protein folding. In addition, clear upregulated expression of the inducible NO synthase (iNOS) with high nitrite levels were observed in RTT fibroblasts, justifying the increased nitrotyrosine protein modifications. The present work describes not only the proteomic profile in RTT fibroblasts, but also identifies the modified proteins by 4-HNE and nitrotyrosine. Of note, for the first time, it appears that a dysregulation of NO pathway can be associated to RTT pathophysiology. In conclusion, the evidence of a wide range of proteins able to forms adducts with 4-HNE, Nitrotyrosine or with both confirms the possible alteration of several aspects of cellular functions that well correlates to the complex clinical features of RTT patients.
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Affiliation(s)
- Alessandra Pecorelli
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy; Child Neuropsychiatry Unit, University Hospital, Azienda Ospedaliera Universitaria Senese (AOUS), Siena, Italy
| | - Carlo Cervellati
- Department of Biomedical and Specialist Surgical Sciences, University of Ferrara, Ferrara, Italy
| | - Alessio Cortelazzo
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Franco Cervellati
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Claudia Sticozzi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Cristiana Mirasole
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Roberto Guerranti
- Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Alessandro Trentini
- Department of Biomedical and Specialist Surgical Sciences, University of Ferrara, Ferrara, Italy
| | - Lello Zolla
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Vinno Savelli
- Department of Medical, Surgery and Neurosciences, University of Siena, Siena, Italy
| | - Joussef Hayek
- Child Neuropsychiatry Unit, University Hospital, Azienda Ospedaliera Universitaria Senese (AOUS), Siena, Italy
| | - Giuseppe Valacchi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy.
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Signorini C, De Felice C, Leoncini S, Møller RS, Zollo G, Buoni S, Cortelazzo A, Guerranti R, Durand T, Ciccoli L, D’Esposito M, Ravn K, Hayek J. MECP2 Duplication Syndrome: Evidence of Enhanced Oxidative Stress. A Comparison with Rett Syndrome. PLoS One 2016; 11:e0150101. [PMID: 26930212 PMCID: PMC4773238 DOI: 10.1371/journal.pone.0150101] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 02/09/2016] [Indexed: 11/30/2022] Open
Abstract
Rett syndrome (RTT) and MECP2 duplication syndrome (MDS) are neurodevelopmental disorders caused by alterations in the methyl-CpG binding protein 2 (MECP2) gene expression. A relationship between MECP2 loss-of-function mutations and oxidative stress has been previously documented in RTT patients and murine models. To date, no data on oxidative stress have been reported for the MECP2 gain-of-function mutations in patients with MDS. In the present work, the pro-oxidant status and oxidative fatty acid damage in MDS was investigated (subjects n = 6) and compared to RTT (subjects n = 24) and healthy condition (subjects n = 12). Patients with MECP2 gain-of-function mutations showed increased oxidative stress marker levels (plasma non-protein bound iron, intraerythrocyte non-protein bound iron, F2-isoprostanes, and F4-neuroprostanes), as compared to healthy controls (P ≤ 0.05). Such increases were similar to those observed in RTT patients except for higher plasma F2-isoprostanes levels (P < 0.0196). Moreover, plasma levels of F2-isoprostanes were significantly correlated (P = 0.0098) with the size of the amplified region. The present work shows unique data in patients affected by MDS. For the first time MECP2 gain-of-function mutations are indicated to be linked to an oxidative damage and related clinical symptoms overlapping with those of MECP2 loss-of-function mutations. A finely tuned balance of MECP2 expression appears to be critical to oxidative stress homeostasis, thus shedding light on the relevance of the redox balance in the central nervous system integrity.
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Affiliation(s)
- Cinzia Signorini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
- * E-mail: (CS); (CDF)
| | - Claudio De Felice
- Neonatal Intensive Care Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
- * E-mail: (CS); (CDF)
| | - Silvia Leoncini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Rikke S. Møller
- Danish Epilepsy Centre, Dianalund, Denmark
- Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Gloria Zollo
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Sabrina Buoni
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Alessio Cortelazzo
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Roberto Guerranti
- Department of Medical Biotechnologies,University of Siena, Siena, Italy
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247-CNRS-UM-ENSCM, Montpellier, France
| | - Lucia Ciccoli
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Maurizio D’Esposito
- Institute of Genetics and Biophysics “A. Buzzati-Traverso”, Naples, Italy
- IRCSS Neuromed, Pozzilli, Italy
| | - Kirstine Ravn
- Department of Clinical Genetics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Joussef Hayek
- Child Neuropsychiatry Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy
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Ma Y, Smith CE, Lai CQ, Irvin MR, Parnell LD, Lee YC, Pham LD, Aslibekyan S, Claas SA, Tsai MY, Borecki IB, Kabagambe EK, Ordovás JM, Absher DM, Arnett DK. The effects of omega-3 polyunsaturated fatty acids and genetic variants on methylation levels of the interleukin-6 gene promoter. Mol Nutr Food Res 2016; 60:410-9. [PMID: 26518637 PMCID: PMC4844557 DOI: 10.1002/mnfr.201500436] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 09/11/2015] [Accepted: 10/21/2015] [Indexed: 01/04/2023]
Abstract
SCOPE Omega-3 PUFAs (n-3 PUFAs) reduce IL-6 gene expression, but their effects on transcription regulatory mechanisms are unknown. We aimed to conduct an integrated analysis with both population and in vitro studies to systematically explore the relationships among n-3 PUFA, DNA methylation, single nucleotide polymorphisms (SNPs), gene expression, and protein concentration of IL6. METHODS AND RESULTS Using data in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study and the Encyclopedia of DNA Elements (ENCODE) consortium, we found that higher methylation of IL6 promoter cg01770232 was associated with higher IL-6 plasma concentration (p = 0.03) and greater IL6 gene expression (p = 0.0005). Higher circulating total n-3 PUFA was associated with lower cg01770232 methylation (p = 0.007) and lower IL-6 concentration (p = 0.02). Moreover, an allele of IL6 rs2961298 was associated with higher cg01770232 methylation (p = 2.55 × 10(-7) ). The association between n-3 PUFA and cg01770232 methylation was dependent on rs2961298 genotype (p = 0.02), but higher total n-3 PUFA was associated with lower cg01770232 methylation in the heterozygotes (p = 0.04) not in the homozygotes. CONCLUSION Higher n-3 PUFA is associated with lower methylation at IL6 promoter, which may be modified by IL6 SNPs.
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Affiliation(s)
- Yiyi Ma
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
- Biomedical Genetics, Department of Medicine, Boston University, Boston, MA, USA
| | - Caren E. Smith
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - Chao-Qiang Lai
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - Marguerite R. Irvin
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Laurence D. Parnell
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - Yu-Chi Lee
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - Lucia D. Pham
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - Stella Aslibekyan
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Steven A. Claas
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Michael Y. Tsai
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA
| | - Ingrid B. Borecki
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | | | - José M. Ordovás
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
- Department of Epidemiology, Centro Nacional Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Alimentacion (IMDEA-FOOD), Madrid, Spain
| | - Devin M. Absher
- Hudson Alpha Institute for Biotechnology, Huntsville, AL, USA
| | - Donna K. Arnett
- Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL, USA
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Abstract
Rett syndrome (RTT) is a devastating neurodevelopmental disease, previously included into the autistic spectrum disorders, affecting almost exclusively females (frequency 1:10,000). RTT leads to intellective deficit, purposeful hands use loss and late major motor impairment besides featuring breathing disorders, epilepsy and increased risk of sudden death. The condition is caused in up to 95% of the cases by mutations in the X-linked methyl-CpG binding protein 2 (MECP2) gene. Our group has shown a number of previously unrecognized features, such as systemic redox imbalance, chronic inflammatory status, respiratory bronchiolitis-associated interstitial lung disease-like lung disease, and erythrocyte morphology changes. While evidence on an intimate involvement of MeCP2 in the immune response is cumulating, we have recently shown a cytokine dysregulation in RTT. Increasing evidence on the relationship between MeCP2 and an immune dysfunction is reported, with, apparently, a link between MECP2 gene polymorphisms and autoimmune diseases, including primary Sjögren's syndrome, systemic lupus erythematosus, rheumatoid arthritis, and systemic sclerosis. Antineuronal (i.e., brain proteins) antibodies have been shown in RTT. Recently, high levels of anti-N-glucosylation (N-Glc) IgM serum autoantibodies [i.e., anti-CSF114(N-Glc) IgMs] have been detected by our group in a statistically significant number of RTT patients. In the current review, the Authors explore the current evidence, either in favor or against, the presence of an autoimmune component in RTT.
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Liu X, Secombe J. The Histone Demethylase KDM5 Activates Gene Expression by Recognizing Chromatin Context through Its PHD Reader Motif. Cell Rep 2015; 13:2219-31. [PMID: 26673323 DOI: 10.1016/j.celrep.2015.11.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/05/2015] [Accepted: 10/31/2015] [Indexed: 12/22/2022] Open
Abstract
KDM5 family proteins are critically important transcriptional regulators whose physiological functions in the context of a whole animal remain largely unknown. Using genome-wide gene expression and binding analyses in Drosophila adults, we demonstrate that KDM5 (Lid) is a direct regulator of genes required for mitochondrial structure and function. Significantly, this occurs independently of KDM5's well-described JmjC domain-encoded histone demethylase activity. Instead, it requires the PHD motif of KDM5 that binds to histone H3 that is di- or trimethylated on lysine 4 (H3K4me2/3). Genome-wide, KDM5 binding overlaps with the active chromatin mark H3K4me3, and a fly strain specifically lacking H3K4me2/3 binding shows defective KDM5 promoter recruitment and gene activation. KDM5 therefore plays a central role in regulating mitochondrial function by utilizing its ability to recognize specific chromatin contexts. Importantly, KDM5-mediated regulation of mitochondrial activity is likely to be key in human diseases caused by dysfunction of this family of proteins.
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Affiliation(s)
- Xingyin Liu
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Julie Secombe
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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45
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Cytokine Dysregulation in MECP2- and CDKL5-Related Rett Syndrome: Relationships with Aberrant Redox Homeostasis, Inflammation, and ω-3 PUFAs. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:421624. [PMID: 26236424 PMCID: PMC4510261 DOI: 10.1155/2015/421624] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 05/19/2015] [Indexed: 12/20/2022]
Abstract
An involvement of the immune system has been suggested in Rett syndrome (RTT), a devastating neurodevelopmental disorder related to oxidative stress, and caused by a mutation in the methyl-CpG binding protein 2 gene (MECP2) or, more rarely, cyclin-dependent kinase-like 5 (CDKL5). To date, it is unclear whether both mutations may have an impact on the circulating cytokine patterns. In the present study, cytokines involved in the Th1-, Th2-, and T regulatory (T-reg) response, as well as chemokines, were investigated in MECP2- (MECP2-RTT) (n = 16) and CDKL5-Rett syndrome (CDKL5-RTT) (n = 8), before and after ω-3 polyunsaturated fatty acids (PUFAs) supplementation. A major cytokine dysregulation was evidenced in untreated RTT patients. In MECP2-RTT, a Th2-shifted balance was evidenced, whereas in CDKL5-RTT both Th1- and Th2-related cytokines (except for IL-4) were upregulated. In MECP2-RTT, decreased levels of IL-22 were observed, whereas increased IL-22 and T-reg cytokine levels were evidenced in CDKL5-RTT. Chemokines were unchanged. The cytokine dysregulation was proportional to clinical severity, inflammatory status, and redox imbalance. Omega-3 PUFAs partially counterbalanced cytokine changes, as well as aberrant redox homeostasis and the inflammatory status. RTT is associated with a subclinical immune dysregulation as the likely consequence of a defective inflammation regulatory signaling system.
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46
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Abstract
Rett syndrome (RTT) is a syndromic autism spectrum disorder caused by loss-of-function mutations in MECP2. The methyl CpG binding protein 2 binds methylcytosine and 5-hydroxymethycytosine at CpG sites in promoter regions of target genes, controlling their transcription by recruiting co-repressors and co-activators. Several preclinical studies in mouse models have identified rational molecular targets for drug therapies aimed at correcting the underlying neural dysfunction. These targeted therapies are increasingly translating into human clinical trials. In this review, we present an overview of RTT and describe the current state of preclinical studies in methyl CpG binding protein 2-based mouse models, as well as current clinical trials in individuals with RTT.
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Affiliation(s)
- Lucas Pozzo-Miller
- />Department of Neurobiology, Civitan International Research Center, The University of Alabama at Birmingham, Birmingham, AL USA
| | - Sandipan Pati
- />Department of Neurology, Epilepsy Division, Civitan International Research Center, The University of Alabama at Birmingham, Birmingham, AL USA
| | - Alan K. Percy
- />Department of Pediatrics, Civitan International Research Center, The University of Alabama at Birmingham, Birmingham, AL USA
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47
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Turovsky E, Karagiannis A, Abdala AP, Gourine AV. Impaired CO2 sensitivity of astrocytes in a mouse model of Rett syndrome. J Physiol 2015; 593:3159-68. [PMID: 25981852 PMCID: PMC4532534 DOI: 10.1113/jp270369] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 05/11/2015] [Indexed: 12/13/2022] Open
Abstract
Rett syndrome, a prototypical neurological disorder caused by loss of function of the transcriptional regulator methyl-CpG-binding protein 2 (MeCP2) gene, is associated with a severely disordered breathing pattern and reduced ventilatory CO2 sensitivity. In a mouse model of Rett syndrome (MeCP2 knockout), re-introduction of the MeCP2 gene selectively in astrocytes rescues normal respiratory phenotype. In the present study we determined whether the metabolic and/or signalling functions of astrocytes are affected by testing the hypotheses that in conditions of MeCP2 deficiency, medullary astrocytes are unable to produce/release appropriate amounts of lactate or detect changes in PCO2/[H(+) ], or both. No differences in tonic or hypoxia-induced release of lactate from the ventral surface of the medulla oblongata or cerebral cortex in brain slices of MeCP2-knockout and wild-type mice were found. In brainstem slices of wild-type mice, respiratory acidosis triggered robust elevations in [Ca(2+) ]i in astrocytes residing near the ventral surface of the medulla oblongata. The magnitude of CO2 -induced [Ca(2+) ]i responses in medullary astrocytes was markedly reduced in conditions of MeCP2 deficiency, whereas [Ca(2+) ]i responses to ATP were unaffected. These data suggest that (i) metabolic function of astrocytes in releasing lactate into the extracellular space is not affected by MeCP2 deficiency, and (ii) MeCP2 deficiency impairs the ability of medullary astrocytes to sense changes in PCO2/[H(+) ]. Taken together with the evidence of severely blunted ventilatory sensitivity to CO2 in mice with conditional MeCP2 deletion in astroglia, these data support the hypothesis of an important role played by astrocytes in central respiratory CO2 /pH chemosensitivity.
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Affiliation(s)
- Egor Turovsky
- Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.,Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Anastassios Karagiannis
- Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ana Paula Abdala
- School of Physiology & Pharmacology, University of Bristol, Bristol, BS8 1TD, UK
| | - Alexander V Gourine
- Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK
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48
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De Filippis B, Valenti D, de Bari L, De Rasmo D, Musto M, Fabbri A, Ricceri L, Fiorentini C, Laviola G, Vacca RA. Mitochondrial free radical overproduction due to respiratory chain impairment in the brain of a mouse model of Rett syndrome: protective effect of CNF1. Free Radic Biol Med 2015; 83:167-77. [PMID: 25708779 DOI: 10.1016/j.freeradbiomed.2015.02.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/09/2015] [Accepted: 02/11/2015] [Indexed: 11/19/2022]
Abstract
Rett syndrome (RTT) is a pervasive neurodevelopmental disorder mainly caused by mutations in the X-linked MECP2 gene associated with severe intellectual disability, movement disorders, and autistic-like behaviors. Its pathogenesis remains mostly not understood and no effective therapy is available. High circulating levels of oxidative stress markers in patients and the occurrence of oxidative brain damage in MeCP2-deficient mouse models suggest the involvement of oxidative stress in RTT pathogenesis. However, the molecular mechanism and the origin of the oxidative stress have not been elucidated. Here we demonstrate that a redox imbalance arises from aberrant mitochondrial functionality in the brain of MeCP2-308 heterozygous female mice, a condition that more closely recapitulates that of RTT patients. The marked increase in the rate of hydrogen peroxide generation in the brain of RTT mice seems mainly produced by the dysfunctional complex II of the mitochondrial respiratory chain. In addition, both membrane potential generation and mitochondrial ATP synthesis are decreased in RTT mouse brains when succinate, the complex II respiratory substrate, is used as an energy source. Respiratory chain impairment is brain area specific, owing to a decrease in either cAMP-dependent phosphorylation or protein levels of specific complex subunits. Further, we investigated whether the treatment of RTT mice with the bacterial protein CNF1, previously reported to ameliorate the neurobehavioral phenotype and brain bioenergetic markers in an RTT mouse model, exerts specific effects on brain mitochondrial function and consequently on hydrogen peroxide production. In RTT brains treated with CNF1, we observed the reactivation of respiratory chain complexes, the rescue of mitochondrial functionality, and the prevention of brain hydrogen peroxide overproduction. These results provide definitive evidence of mitochondrial reactive oxygen species overproduction in RTT mouse brain and highlight CNF1 efficacy in counteracting RTT-related mitochondrial defects.
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Affiliation(s)
- Bianca De Filippis
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, 00161 Roma, Italy.
| | - Daniela Valenti
- Institute of Biomembranes and Bioenergetics, National Council of Research, Bari, Italy
| | - Lidia de Bari
- Institute of Biomembranes and Bioenergetics, National Council of Research, Bari, Italy
| | - Domenico De Rasmo
- Institute of Biomembranes and Bioenergetics, National Council of Research, Bari, Italy
| | - Mattia Musto
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, 00161 Roma, Italy
| | - Alessia Fabbri
- Department of Therapeutic Research and Medicine Evaluation, Istituto Superiore di Sanità, 00161 Roma, Italy
| | - Laura Ricceri
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, 00161 Roma, Italy
| | - Carla Fiorentini
- Department of Therapeutic Research and Medicine Evaluation, Istituto Superiore di Sanità, 00161 Roma, Italy
| | - Giovanni Laviola
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, 00161 Roma, Italy
| | - Rosa Anna Vacca
- Institute of Biomembranes and Bioenergetics, National Council of Research, Bari, Italy.
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49
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De Felice C, Signorini C, Leoncini S, Durand T, Ciccoli L, Hayek J. Oxidative stress: a hallmark of Rett syndrome. FUTURE NEUROLOGY 2015. [DOI: 10.2217/fnl.15.9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Claudio De Felice
- Neonatal Intensive Care Unit, University Hospital Azienda Ospedaliera Universitaria Senese (AOUS), Policlinico “S. M. alle Scotte”, I-53100 Siena, Italy
| | - Cinzia Signorini
- Department of Molecular & Developmental Medicine, University of Siena, I-53100 Siena, Italy
| | - Silvia Leoncini
- Department of Molecular & Developmental Medicine, University of Siena, I-53100 Siena, Italy
- Child Neuropsychiatry Unit, University Hospital (AOUS), I-53100 Siena, Italy
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron (IBMM), UMR 5247- CNRS-UM -ENSCM, BP 14491, 34093, Montpellier, Cedex 5, France
| | - Lucia Ciccoli
- Department of Molecular & Developmental Medicine, University of Siena, I-53100 Siena, Italy
| | - Joussef Hayek
- Child Neuropsychiatry Unit, University Hospital (AOUS), I-53100 Siena, Italy
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50
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Hami J, Shojae F, Vafaee-Nezhad S, Lotfi N, Kheradmand H, Haghir H. Some of the experimental and clinical aspects of the effects of the maternal diabetes on developing hippocampus. World J Diabetes 2015; 6:412-422. [PMID: 25897352 PMCID: PMC4398898 DOI: 10.4239/wjd.v6.i3.412] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 10/25/2014] [Accepted: 01/12/2015] [Indexed: 02/05/2023] Open
Abstract
Diabetes mellitus during pregnancy is associated with an increased risk of multiple congenital anomalies in progeny. There are sufficient evidence suggesting that the children of diabetic women exhibit intellectual and behavioral abnormalities accompanied by modification of hippocampus structure and function. Although, the exact mechanism by which maternal diabetes affects the developing hippocampus remains to be defined. Multiple biological alterations, including hyperglycemia, hyperinsulinemia, oxidative stress, hypoxia, and iron deficiency occur in pregnancies with diabetes and affect the development of central nervous system (CNS) of the fetus. The conclusion from several studies is that disturbance in glucose and insulin homeostasis in mothers and infants are major teratogenic factor in the development of CNS. Insulin and Insulin-like growth factor-1 (IGF-1) are two key regulators of CNS function and development. Insulin and IGF-1 receptors (IR and IGF1R, respectively) are distributed in a highly specific pattern with the high density in some brain regions such as hippocampus. Recent researches have clearly established that maternal diabetes disrupts the regulation of both IR and IGF1R in the hippocampus of rat newborn. Dissecting out the mechanisms responsible for maternal diabetes-related changes in the development of hippocampus is helping to prevent from impaired cognitive and memory functions in offspring.
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