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Spencer PS, Valdes Angues R, Palmer VS. Nodding syndrome: A role for environmental biotoxins that dysregulate MECP2 expression? J Neurol Sci 2024; 462:123077. [PMID: 38850769 DOI: 10.1016/j.jns.2024.123077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 05/15/2024] [Accepted: 05/30/2024] [Indexed: 06/10/2024]
Abstract
Nodding syndrome is an epileptic encephalopathy associated with neuroinflammation and tauopathy. This initially pediatric brain disease, which has some clinical overlap with Methyl-CpG-binding protein 2 (MECP2) Duplication Syndrome, has impacted certain impoverished East African communities coincident with local civil conflict and internal displacement, conditions that forced dependence on contaminated food and water. A potential role in Nodding syndrome for certain biotoxins (freshwater cyanotoxins plus/minus mycotoxins) with neuroinflammatory, excitotoxic, tauopathic, and MECP2-dysregulating properties, is considered here for the first time.
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Affiliation(s)
- Peter S Spencer
- Department of Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA; Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA; Gulu University School of Medicine, Gulu, Uganda.
| | - Raquel Valdes Angues
- Department of Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Valerie S Palmer
- Department of Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA; Gulu University School of Medicine, Gulu, Uganda
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Jiang Z, Sullivan PF, Li T, Zhao B, Wang X, Luo T, Huang S, Guan PY, Chen J, Yang Y, Stein JL, Li Y, Liu D, Sun L, Zhu H. The pivotal role of the X-chromosome in the genetic architecture of the human brain. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2023.08.30.23294848. [PMID: 37693466 PMCID: PMC10491353 DOI: 10.1101/2023.08.30.23294848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Genes on the X-chromosome are extensively expressed in the human brain. However, little is known for the X-chromosome's impact on the brain anatomy, microstructure, and functional network. We examined 1,045 complex brain imaging traits from 38,529 participants in the UK Biobank. We unveiled potential autosome-X-chromosome interactions, while proposing an atlas outlining dosage compensation (DC) for brain imaging traits. Through extensive association studies, we identified 72 genome-wide significant trait-locus pairs (including 29 new associations) that share genetic architectures with brain-related disorders, notably schizophrenia. Furthermore, we discovered unique sex-specific associations and assessed variations in genetic effects between sexes. Our research offers critical insights into the X-chromosome's role in the human brain, underscoring its contribution to the differences observed in brain structure and functionality between sexes.
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Zeng L, Zhu H, Wang J, Wang Q, Pang Y, Luo Z, Chen A, Qin S, Zhu S. Genetic analysis of a pedigree with MECP2 duplication syndrome in China. BMC Med Genomics 2024; 17:54. [PMID: 38373942 PMCID: PMC10875745 DOI: 10.1186/s12920-024-01831-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 02/10/2024] [Indexed: 02/21/2024] Open
Abstract
BACKGROUND MECP2 duplication syndrome (MDS) is a rare X-linked genomic disorder that primarily affects males. It is characterized by delayed or absent speech development, severe motor and cognitive impairment, and recurrent respiratory infections. MDS is caused by the duplication of a chromosomal region located on chromosome Xq28, which contains the methyl CpG binding protein-2 (MECP2) gene. MECP2 functions as a transcriptional repressor or activator, regulating genes associated with nervous system development. The objective of this study is to provide a clinical description of MDS, including imaging changes observed from the fetal period to the neonatal period. METHODS Conventional G-banding was employed to analyze the chromosome karyotypes of all pedigrees under investigation. Subsequently, whole exome sequencing (WES), advanced biological information analysis, and pedigree validation were conducted, which were further confirmed by copy number variation sequencing (CNV-seq). RESULTS Chromosome karyotype analysis revealed that a male patient had a chromosome karyotype of 46,Y,dup(X)(q27.2q28). Whole-exon duplication in the MECP2 gene was revealed through WES results. CNV-seq validation confirmed the presence of Xq27.1q28 duplicates spanning 14.45 Mb, which was inherited from a mild phenotype mother. Neither the father nor the mother's younger brother carried this duplication. CONCLUSION In this study, we examined a male child in a family who exhibited developmental delay and recurrent respiratory tract infections as the main symptoms. We conducted thorough family investigations and genetic testing to determine the underlying causes of the disease. Our findings will aid in early diagnosis, genetic counseling for male patients in this family, as well as providing prenatal diagnosis and reproductive guidance for female carriers.
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Affiliation(s)
- Lan Zeng
- Department of Medical Genetics and Prenatal Diagnosis, Sichuan Provincial Maternity and Child Health Care Hospital, Chengdu, Sichuan, China
| | - Hui Zhu
- Department of Pediatrics, Sichuan Provincial Maternity and Child Health Care Hospital, No. 290, Sha Yan West 2Nd Road, Chengdu, 610031, Sichuan, China
| | - Jin Wang
- Department of Medical Genetics and Prenatal Diagnosis, Sichuan Provincial Maternity and Child Health Care Hospital, Chengdu, Sichuan, China
| | - Qiyan Wang
- Department of Radiology, Sichuan Provincial Maternity and Child Health Care Hospital, Chengdu, Sichuan, China
| | - Ying Pang
- Department of Pediatrics, Sichuan Provincial Maternity and Child Health Care Hospital, No. 290, Sha Yan West 2Nd Road, Chengdu, 610031, Sichuan, China
| | - Zemin Luo
- Department of Pediatrics, Sichuan Provincial Maternity and Child Health Care Hospital, No. 290, Sha Yan West 2Nd Road, Chengdu, 610031, Sichuan, China
| | - Ai Chen
- Department of Pediatrics, Sichuan Provincial Maternity and Child Health Care Hospital, No. 290, Sha Yan West 2Nd Road, Chengdu, 610031, Sichuan, China
| | - Shengfang Qin
- Department of Medical Genetics and Prenatal Diagnosis, Sichuan Provincial Maternity and Child Health Care Hospital, Chengdu, Sichuan, China
| | - Shuyao Zhu
- Department of Pediatrics, Sichuan Provincial Maternity and Child Health Care Hospital, No. 290, Sha Yan West 2Nd Road, Chengdu, 610031, Sichuan, China.
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Balicza P, Gezsi A, Fedor M, Sagi JC, Gal A, Varga NA, Molnar MJ. Multilevel evidence of MECP2-associated mitochondrial dysfunction and its therapeutic implications. Front Psychiatry 2024; 14:1301272. [PMID: 38250256 PMCID: PMC10796460 DOI: 10.3389/fpsyt.2023.1301272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Accepted: 11/22/2023] [Indexed: 01/23/2024] Open
Abstract
We present a male patient carrying a pathogenic MECP2 p. Arg179Trp variant with predominant negative psychiatric features and multilevel evidence of mitochondrial dysfunction who responded to the cariprazine treatment. He had delayed speech development and later experienced severe social anxiety, learning disabilities, cognitive slowing, and predominant negative psychiatric symptoms associated with rigidity. Clinical examinations showed multisystemic involvement. Together with elevated ergometric lactate levels, the clinical picture suggested mitochondrial disease, which was also supported by muscle histopathology. Exploratory transcriptome analysis also revealed the involvement of metabolic and oxidative phosphorylation pathways. Whole-exome sequencing identified a pathogenic MECP2 variant, which can explain both the dopamine imbalance and mitochondrial dysfunction in this patient. Mitochondrial dysfunction was previously suggested in classical Rett syndrome, and we detected related phenotype evidence on multiple consistent levels for the first time in a MECP2 variant carrier male. This study further supports the importance of the MECP2 gene in the mitochondrial pathways, which can open the gate for more personalized therapeutic interventions. Good cariprazine response highlights the role of dopamine dysfunction in the complex psychiatric symptoms of Rett syndrome. This can help identify the optimal treatment strategy from a transdiagnostic perspective instead of a classical diagnostic category.
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Affiliation(s)
- Peter Balicza
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
- Eotvos Lorand Research Network, Multiomic Neurodegeneration Research Group, Budapest, Hungary
| | - Andras Gezsi
- Department of Measurement and Information Systems, Budapest University of Technology and Economics, Budapest, Hungary
| | - Mariann Fedor
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Judit C. Sagi
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Aniko Gal
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Noemi Agnes Varga
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Maria Judit Molnar
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
- Eotvos Lorand Research Network, Multiomic Neurodegeneration Research Group, Budapest, Hungary
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Sadhu C, Lyons C, Oh J, Jagadeeswaran I, Gray SJ, Sinnett SE. The Efficacy of a Human-Ready mini MECP2 Gene Therapy in a Pre-Clinical Model of Rett Syndrome. Genes (Basel) 2023; 15:31. [PMID: 38254921 PMCID: PMC10815157 DOI: 10.3390/genes15010031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024] Open
Abstract
Inactivating mutations and the duplication of methyl-CpG binding protein 2 (MeCP2), respectively, mediate Rett syndrome (RTT) and MECP2 duplication syndrome. These disorders underscore the conceptual dose-dependent risk posed by MECP2 gene therapy for mosaic RTT patients. Recently, a miRNA-Responsive Autoregulatory Element (miRARE) mitigated the dose-dependent toxicity posed by self-complementary adeno-associated viral vector serotype 9 (AAV9) miniMECP2 gene therapy (scAAV9/miniMECP2-myc) in mice. Here, we report an efficacy assessment for the human-ready version of this regulated gene therapy (TSHA-102) in male Mecp2-/y knockout (KO) mice after intracerebroventricular (ICV) administration at postnatal day 2 (P2) and after intrathecal (IT) administration at P7, P14 (±immunosuppression), and P28 (±immunosuppression). We also report qPCR studies on KO mice treated at P7-P35; protein analyses in KO mice treated at P38; and a survival safety study in female adult Mecp2-/+ mice. In KO mice, TSHA-102 improved respiration, weight, and survival across multiple doses and treatment ages. TSHA-102 significantly improved the front average stance and swing times relative to the front average stride time after P14 administration of the highest dose for that treatment age. Viral genomic DNA and miniMECP2 mRNA were present in the CNS. MiniMeCP2 protein expression was higher in the KO spinal cord compared to the brain. In female mice, TSHA-102 permitted survivals that were similar to those of vehicle-treated controls. In all, these pivotal data helped to support the regulatory approval to initiate a clinical trial for TSHA-102 in RTT patients (clinical trial identifier number NCT05606614).
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Affiliation(s)
- Chanchal Sadhu
- Formerly of Taysha Gene Therapies, Dallas, TX 75247, USA
| | - Christopher Lyons
- Formerly of the Department of Pediatrics, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
| | - Jiyoung Oh
- Department of Pediatrics, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
| | - Indumathy Jagadeeswaran
- Department of Pediatrics, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
| | - Steven J. Gray
- Department of Pediatrics, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
| | - Sarah E. Sinnett
- Department of Pediatrics, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
- Peter O’Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center (UTSWMC), Dallas, TX 75390, USA
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Liang J, Xin C, Xin M, Wang G, Wu X. An insertion mutation of the MECP2 gene in severe neonatal encephalopathy and ocular and oropharyngeal dyskinesia: a case report. BMC Med Genomics 2023; 16:181. [PMID: 37537631 PMCID: PMC10398912 DOI: 10.1186/s12920-023-01616-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 07/26/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND Pathogenic variation of the MECP2 gene presents mostly as Rett syndrome in females and is extremely rare in males. Most male patients with MECP2 gene mutation show MECP2 duplication syndrome. CASE PRESENTATION Here we report a rare case in a 10-month-old boy with a hemizygous insertion mutation in MECP2 as NM_001110792, c.799_c.800insAGGAAGC, which results in a frameshift mutation (p.R267fs*6). The patient presented with severe encephalopathy in the neonatal period, accompanied by severe development backwardness, hypotonia, and ocular and oropharyngeal dyskinesia. This is the first report of this mutation, which highlights the phenotype variability associated with MECP2 variants. CONCLUSIONS This case helps to expand the clinical spectrum associated with MECP2 variants. Close attention should be paid to the growth and development of patients carrying a MECP2 variant or Xq28 duplication. Early interventions may help improve symptoms to some certain extent.
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Affiliation(s)
- Jianmin Liang
- Department of Pediatric, Neurology of Jilin University, 1 Xinmin Street, Changchun, 130000, Jilin Province, China
- Jilin Provincial Key Laboratory of Pediatric Neurology, Changchun, China
| | - Cuijuan Xin
- Department of Pediatric, Neurology of Jilin University, 1 Xinmin Street, Changchun, 130000, Jilin Province, China
| | - Meiying Xin
- Department of Pediatric, Neurology of Jilin University, 1 Xinmin Street, Changchun, 130000, Jilin Province, China
| | - Guangliang Wang
- Department of Cardiology, Jiren Hospital of Far Eastern Horizon, Anda, China
| | - Xuemei Wu
- Department of Pediatric, Neurology of Jilin University, 1 Xinmin Street, Changchun, 130000, Jilin Province, China.
- Jilin Provincial Key Laboratory of Pediatric Neurology, Changchun, China.
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Shalata A, Bar-Shai M, Hadid Y, Mahroum M, Mintz H, Shalata ZE, Radzishevsky E, Genizi J, Lorber A, Ben-Yosef T, Yaniv L. Danon Disease: Entire LAMP2 Gene Deletion with Unusual Clinical Presentation-Case Report and Review of the Literature. Genes (Basel) 2023; 14:1539. [PMID: 37628591 PMCID: PMC10454823 DOI: 10.3390/genes14081539] [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: 06/01/2023] [Revised: 07/17/2023] [Accepted: 07/25/2023] [Indexed: 08/27/2023] Open
Abstract
Danon disease is a rare x-linked dominant multisystemic disorder with a clinical triad of severe cardiomyopathy, skeletal myopathy, and intellectual disability. It is caused by defects in the lysosome-associated membrane protein-2 (LAMP2) gene. Numerous different mutations in the LAMP2 protein have been described. Danon disease is typically lethal by the mid-twenties in male patients due to cardiomyopathy and heart failure. Female patients usually present with milder and variable symptoms. This report describes a 42-year-old father and his 3-year-old daughter presenting with mild manifestations of the disease. The father has normal intellectual development and normal physical activity. At the age of 13, he was diagnosed with mild ventricular pre-excitation known as Wolf-Parkinson-White syndrome (WPWs), very mild and mostly asymptomatic cardiomyopathy and left ventricular hypertrophy, and at about the age of 25 presented with visual impairment due to cone-rod dystrophy. His daughter showed normal development and very mild asymptomatic electrocardiographic WPWs abnormalities with left mild ventricular hypertrophy. Genetic testing revealed an Xq24 microdeletion encompassing the entire LAMP2 gene. Relevant literature was reviewed as a reference for the etiology, diagnosis, treatment and case management.
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Affiliation(s)
- Adel Shalata
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
| | - Marina Bar-Shai
- The Institute of Medical Genetics, Carmel Medical Center, Haifa 34362, Israel;
| | - Yarin Hadid
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
| | - Muhammad Mahroum
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
| | - Hila Mintz
- The Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, Haifa 32000, Israel; (Y.H.); (M.M.); (H.M.)
| | | | - Evgeny Radzishevsky
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Cardiology Department, Bnai Zion Medical Center, Haifa 32000, Israel
| | - Jacob Genizi
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Department of Pediatric, Bnai Zion Medical Center, Haifa 32000, Israel
| | - Avraham Lorber
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Pediatric Cardiology Unit, Rambam Medical Centre, Haifa 31096, Israel
| | - Tamar Ben-Yosef
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
| | - Liat Yaniv
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 32000, Israel; (E.R.); (J.G.); (A.L.); (T.B.-Y.); (L.Y.)
- Department of Pediatric, Bnai Zion Medical Center, Haifa 32000, Israel
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Masri AT, Oweis L, Ali M, Hamamy H. Global developmental delay and intellectual disability in the era of genomics: Diagnosis and challenges in resource limited areas. Clin Neurol Neurosurg 2023; 230:107799. [PMID: 37236004 DOI: 10.1016/j.clineuro.2023.107799] [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: 01/13/2023] [Revised: 05/12/2023] [Accepted: 05/22/2023] [Indexed: 05/28/2023]
Abstract
AIMS To report the diagnostic yield of clinical singleton whole exome sequencing (WES) performed among a group of Jordanian children presenting with global developmental delay /intellectual disability (GDD/ID), discuss the underlying identified genetic disorders and the challenges encountered. PATIENTS AND METHODS This retrospective medical record review study included 154 children who were diagnosed with GDD/ID at our clinic at Jordan University Hospital between 2016 and 2021, and whose diagnostic work up included WES. RESULTS Consanguinity among parents was reported in 94/154 (61.0%) patients and history of other affected siblings in 35/154 (22.7%) patients. Pathogenic and likely pathogenic variants (solved cases) were reported in 69/154 (44.8%) patients, a variant of uncertain significance was reported in 54/154 (35.0%) and a negative result was reported in 31/154 (20.1%) cases. In the solved cases, autosomal recessive diseases were the most common (33/69; 47.8%). Metabolic disorders were identified in 20/69 (28.9%) patients, followed by developmental and epileptic encephalopathies (9/69; 13.0%) and MECP2 related disorders (7/69; 10.1%). Other single gene disorders were identified in 33/69; 47.8%) patients. CONCLUSION This study had several limitations, as it was hospital-based and only including patients who were able to afford the test. Nevertheless, it yielded several important findings. In resource-limited countries, WES may be a reasonable approach. We discussed the challenges that clinicians meet in the context of shortage of resources.
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Affiliation(s)
- Amira T Masri
- Faculty of Medicine, Paediatric Department, Division of Child Neurology, The University of Jordan, Jordan.
| | - Liyana Oweis
- Faculty of Medicine, The University of Jordan, Jordan
| | - Majd Ali
- Faculty of Medicine, The University of Jordan, Jordan
| | - Hanan Hamamy
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland
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Fogarty MJ. Inhibitory Synaptic Influences on Developmental Motor Disorders. Int J Mol Sci 2023; 24:ijms24086962. [PMID: 37108127 PMCID: PMC10138861 DOI: 10.3390/ijms24086962] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
During development, GABA and glycine play major trophic and synaptic roles in the establishment of the neuromotor system. In this review, we summarise the formation, function and maturation of GABAergic and glycinergic synapses within neuromotor circuits during development. We take special care to discuss the differences in limb and respiratory neuromotor control. We then investigate the influences that GABAergic and glycinergic neurotransmission has on two major developmental neuromotor disorders: Rett syndrome and spastic cerebral palsy. We present these two syndromes in order to contrast the approaches to disease mechanism and therapy. While both conditions have motor dysfunctions at their core, one condition Rett syndrome, despite having myriad symptoms, has scientists focused on the breathing abnormalities and their alleviation-to great clinical advances. By contrast, cerebral palsy remains a scientific quagmire or poor definitions, no widely adopted model and a lack of therapeutic focus. We conclude that the sheer abundance of diversity of inhibitory neurotransmitter targets should provide hope for intractable conditions, particularly those that exhibit broad spectra of dysfunction-such as spastic cerebral palsy and Rett syndrome.
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Affiliation(s)
- Matthew J Fogarty
- Department of Physiology & Biomedical Engineering, Mayo Clinic, Rochester, MN 55902, USA
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Chen Y, Chang Y, Zhou J, Lv L, Ying H. Inhibiting lncRNA NEAT1 facilitates the sensitization of melanoma cells to cisplatin through modulating the miR-519c-3p-MeCP2 axis. Pathol Res Pract 2023; 243:154364. [PMID: 36841132 DOI: 10.1016/j.prp.2023.154364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 02/01/2023] [Accepted: 02/04/2023] [Indexed: 02/09/2023]
Abstract
Cutaneous melanoma is an aggressive human malignancy, leading to high mortality worldwide. In addition to surgery, radiotherapy and chemotherapy are routine approaches to treat melanoma at late or metastatic stage. However, a group of melanoma patients developed chemoresistance, which ultimately limited the efficiency of chemotherapy. LncRNA NEAT1 (Nuclear-enriched abundant transcript 1) is frequently overexpressed in various cancers. Currently, the precise roles and underlying mechanisms of NEAT1 in chemoresistant melanoma remain unclear. This study reports NEAT1 was significantly upregulated in melanoma tumor specimens and cell lines. Blocking NEAT1 effectively sensitized melanoma cells to cisplatin (CDDP), a frequently used first-line anticancer agent. From the established cisplatin resistant melanoma cell line (SK-MEL-5 CDDP Res), we detected significantly upregulated NEAT1 expression and downregulated miR-519c-3p expression compared with those from SK-MEL-5 parental cells. Subsequently, expression of miR-519c-3p was remarkedly attenuated in melanoma tumors and cell lines. Bioinformatics analysis, RNA pull-down assay and luciferase assay consistently demonstrated that NEAT1 sponged miR-519c-3p to downregulate its expression in melanoma cells. Moreover, we identified the methyl CpG binding protein 2 (MeCP2), which is positively associated with cisplatin resistance in melanoma, was a direct target of miR-519c-3p in melanoma cells. Restoration of MeCP2 rescued the miR-519c-3p-promoted cisplatin sensitization. Finally, we showed restoration of miR-519c-3p in NEAT1-overexpressing SK-MEL-5 CDDP Res cells successfully overrode the NEAT1-promoted cisplatin resistance in melanoma from in vitro and in vivo results. In summary, our results unveiled biological roles and molecular mechanisms of the noncoding RNA-mediated cisplatin resistance in melanoma, suggesting blocking the NEAT1-miR-519c-3p-MeCP2 axis as a therapeutic strategy against chemoresistant melanoma.
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Affiliation(s)
- Yan Chen
- Department of Dermatology, First People's Hospital of Linping District, Zhejiang Province 311100, China
| | - Yan Chang
- Department of Dermatology, First People's Hospital of Linping District, Zhejiang Province 311100, China
| | - Jianping Zhou
- Department of Dermatology, First People's Hospital of Linping District, Zhejiang Province 311100, China
| | - Linna Lv
- Department of Dermatology, First People's Hospital of Linping District, Zhejiang Province 311100, China
| | - Hangyu Ying
- Department of Dermatology, Hangzhou Hospital of Traditional Chinese Medicine, Zhejiang Province 310012, China.
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Modeling RTT Syndrome by iPSC-Derived Neurons from Male and Female Patients with Heterogeneously Severe Hot-Spot MECP2 Variants. Int J Mol Sci 2022; 23:ijms232214491. [PMID: 36430969 PMCID: PMC9697612 DOI: 10.3390/ijms232214491] [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: 10/11/2022] [Revised: 11/07/2022] [Accepted: 11/15/2022] [Indexed: 11/23/2022] Open
Abstract
Rett syndrome caused by MECP2 variants is characterized by a heterogenous clinical spectrum accounted for in 60% of cases by hot-spot variants. Focusing on the most frequent variants, we generated in vitro iPSC-neurons from the blood of RTT girls with p.Arg133Cys and p.Arg255*, associated to mild and severe phenotype, respectively, and of an RTT male harboring the close to p.Arg255*, p.Gly252Argfs*7 variant. Truncated MeCP2 proteins were revealed by Western blot and immunofluorescence analysis. We compared the mutant versus control neurons at 42 days for morphological parameters and at 120 days for electrophysiology recordings, including girls' isogenic clones. A precocious reduced morphological complexity was evident in neurons with truncating variants, while in p.Arg133Cys neurons any significant differences were observed in comparison with the isogenic wild-type clones. Reduced nuclear size and branch number show up as the most robust biomarkers. Patch clamp recordings on mature neurons allowed the assessment of cell biophysical properties, V-gated currents, and spiking pattern in the mutant and control cells. Immature spiking, altered cell capacitance, and membrane resistance of RTT neurons, were particularly pronounced in the Arg255* and Gly252Argfs*7 mutants. The overall results indicate that the specific markers of in vitro cellular phenotype mirror the clinical severity and may be amenable to drug testing for translational purposes.
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Courgeon L, Uguen K, Lefranc J, Lesca G, Ropars J. MECP2 Dysautonomia Phenotypes in Boys. Pediatr Neurol 2022; 134:31-36. [PMID: 35809380 DOI: 10.1016/j.pediatrneurol.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 02/13/2022] [Accepted: 06/02/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Recognizing and identifying dysautonomia would facilitate the diagnosis and management of MECP2 mutations in boys. We aimed to explore the prevalence of dysautonomia symptoms in boys with MECP2 mutations. METHOD We conducted a national, retrospective study (2000-2020) of medical records from boys who were aged less than 18 years when diagnosed with a pathogenic, or likely pathogenic, variant in the MECP2 gene. We systematically looked for dysautonomic signs in the cardiovascular, respiratory, gastrointestinal, and thermoregulatory systems. RESULTS Nine of the 13 cases had at least one system affected by dysautonomia. Two patient subgroups were identified: (1) patients who were ambulatory with intellectual or learning disabilities (n = 6/13 cases) and (2) patients who were unable to walk normally with severe encephalopathy (n = 7/13 cases). Dysautonomic signs were found in both subgroups: 7 of seven patients in the severe array subgroup and 2 of six in the mild array subgroup. CONCLUSIONS These results support MECP2 testing and dysautonomia investigations in both young males who present with encephalopathy and those with intellectual disabilities.
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Affiliation(s)
- Lisa Courgeon
- Department of Neuropediatrics, Brest University Hospital, Brest, France.
| | - Kévin Uguen
- Department of Genetics, Brest University Hospital, Brest, France
| | - Jérémie Lefranc
- Department of Neuropediatrics, Reference Centre for Epilepsy, Brest University Hospital, Brest, France
| | - Gaetan Lesca
- Department of Genetics, Lyon University Hospital, Bron cedex, France
| | - Juliette Ropars
- Department of Neuropediatrics, Brest University Hospital, LaTIM INSERM UMR 1101, Brest, France
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Torres-Pérez JV, Martínez-Rodríguez E, Forte A, Blanco-Gómez C, Stork O, Lanuza E, Santos M, Agustín-Pavón C. Early life stress exacerbates behavioural and neuronal alterations in adolescent male mice lacking methyl-CpG binding protein 2 (Mecp2). Front Behav Neurosci 2022; 16:974692. [PMID: 36082308 PMCID: PMC9447412 DOI: 10.3389/fnbeh.2022.974692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 07/25/2022] [Indexed: 11/17/2022] Open
Abstract
The methyl-CpG binding protein 2 gene (MECP2) encodes an epigenetic transcriptional regulator implicated in neuronal plasticity. Loss-of-function mutations in this gene are the primary cause of Rett syndrome and, to a lesser degree, of other neurodevelopmental disorders. Recently, we demonstrated that both Mecp2 haploinsuficiency and mild early life stress decrease anxiety-like behaviours and neuronal activation in brain areas controlling these responses in adolescent female mice. Here, we extend this work to males by using Mecp2-null and wild type adolescent mice subjected to maternal separation and their non-stressed controls. We assessed their behavioural responses in a battery of anxiety-provoking tests. Upon exposure to an elevated plus maze in aversive conditions, we evaluated changes in c-FOS expression in stress- and anxiety-related brain regions. In addition, we assessed the impact of maternal separation in neuronal maturation using doublecortin and reelin as surrogate markers. Mutant males showed reduced motor abilities, increased activation of the olfactory bulbs, probably due to breathing abnormalities, and decreased activation of the paraventricular thalamic nucleus, when compared to wild type mice. In addition, maternal separation increased the number of immature doublecortin-like neurons found in Mecp2-null animals. Moreover, this work shows for the first time that reelin is decreased in the mutant animals at the olfactory tubercle, piriform cortex and hippocampal dentate gyrus, an effect also associated to maternal separation. Taken together, our results suggest that maternal separation exacerbates some phenotypical alterations associated with lack of MeCP2 in adolescent males.
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Affiliation(s)
- Jose Vicente Torres-Pérez
- Unitat Mixta d’Investigació en Neuroanatomia Funcional, Departament de Biologia Cel⋅lular, Biologia Funcional i Antropologia Física, Universitat de València, València, Spain
| | - Elena Martínez-Rodríguez
- Unitat Mixta d’Investigació en Neuroanatomia Funcional, Departament de Biologia Cel⋅lular, Biologia Funcional i Antropologia Física, Universitat de València, València, Spain
| | - Anabel Forte
- Department of Statistics and Operational Research, Universitat de València, Valencia, Spain
| | - Carlos Blanco-Gómez
- Unitat Mixta d’Investigació en Neuroanatomia Funcional, Departament de Biologia Cel⋅lular, Biologia Funcional i Antropologia Física, Universitat de València, València, Spain
| | - Oliver Stork
- Department of Genetics and Molecular Neurobiology, Institute of Biology, Otto-von-Guericke University, Magdeburg, Germany
| | - Enrique Lanuza
- Unitat Mixta d’Investigació en Neuroanatomia Funcional, Departament de Biologia Cel⋅lular, Biologia Funcional i Antropologia Física, Universitat de València, València, Spain
| | - Mónica Santos
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
- Institute for Interdisciplinary Research, University of Coimbra (IIIUC), Coimbra, Portugal
- *Correspondence: Mónica Santos, ;
| | - Carmen Agustín-Pavón
- Unitat Mixta d’Investigació en Neuroanatomia Funcional, Departament de Biologia Cel⋅lular, Biologia Funcional i Antropologia Física, Universitat de València, València, Spain
- Carmen Agustín-Pavón,
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Design and outcome measures of LAVENDER, a phase 3 study of trofinetide for Rett syndrome. Contemp Clin Trials 2022; 114:106704. [PMID: 35149233 DOI: 10.1016/j.cct.2022.106704] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/01/2022] [Accepted: 02/02/2022] [Indexed: 11/23/2022]
Abstract
INTRODUCTION Rett syndrome (RTT) is a debilitating neurodevelopmental disorder with no approved treatments. Trofinetide is a synthetic analog of glycine-proline-glutamate, the N-terminal tripeptide of insulin-like growth factor 1. In a phase 2, placebo-controlled trial in 82 females with RTT aged 5-15 years, a significant (p ≤ 0.042) improvement over placebo was observed with the highest trofinetide dose (200 mg/kg twice daily [BID]) on three measures: Rett Syndrome Behavior Questionnaire (RSBQ), Clinical Global Impression-Improvement (CGI-I), and RTT-Clinician Domain Specific Concerns-Visual Analog Scale (RTT-DSC-VAS). Trofinetide was well tolerated at all doses (50, 100, and 200 mg/kg BID). A phase 3 trial utilizing disease-specific and novel scales was designed to investigate the efficacy and safety of trofinetide in girls and women with RTT. METHODS This 12-week, double-blind, randomized, placebo-controlled study (LAVENDER; NCT04181723) will evaluate trofinetide in 187 females, aged 5-20 years, with RTT. Co-primary endpoints are the RSBQ and CGI-I scales. Clinical domains of the CGI-I include communication, ambulation, hand use, seizures, attentiveness, and social (eye contact) and autonomic (breathing) aspects. Secondary endpoints will leverage four novel RTT-specific clinician ratings (derived from the RTT-DSC-VAS) of hand function, ambulation, ability to communicate, and verbal communication, and existing scales, to evaluate other core symptoms of RTT, quality of life and caregiver burden. A 40-week, open-label extension study will follow. DISCUSSION This study was designed using disease-specific scales optimized to demonstrate changes in core symptoms of RTT and may provide the first phase 3 data demonstrating drug efficacy in individuals with RTT. TRIAL REGISTRATION Clinicaltrials.govNCT04181723.
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