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Arezoumand KS, Roberts CT, Rastegar M. Metformin Induces MeCP2 in the Hippocampus of Male Mice with Sex-Specific and Brain-Region-Dependent Molecular Impact. Biomolecules 2024; 14:505. [PMID: 38672521 DOI: 10.3390/biom14040505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/29/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024] Open
Abstract
Rett Syndrome (RTT) is a progressive X-linked neurodevelopmental disorder with no cure. RTT patients show disease-associated symptoms within 18 months of age that include developmental regression, progressive loss of useful hand movements, and breathing difficulties, along with neurological impairments, seizures, tremor, and mental disability. Rett Syndrome is also associated with metabolic abnormalities, and the anti-diabetic drug metformin is suggested to be a potential drug of choice with low or no side-effects. Previously, we showed that in vitro exposure of metformin in a human brain cell line induces MECP2E1 transcripts, the dominant isoform of the MECP2 gene in the brain, mutations in which causes RTT. Here, we report the molecular impact of metformin in mice. Protein analysis of specific brain regions in the male and female mice by immunoblotting indicated that metformin induces MeCP2 in the hippocampus, in a sex-dependent manner. Additional experiments confirm that the regulatory role of metformin on the MeCP2 target "BDNF" is brain region-dependent and sex-specific. Measurement of the ribosomal protein S6 (in both phosphorylated and unphosphorylated forms) confirms the sex-dependent role of metformin in the liver. Our results can help foster a better understanding of the molecular impact of metformin in different brain regions of male and female adult mice, while providing some insight towards its potential in therapeutic strategies for the treatment of Rett Syndrome.
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Affiliation(s)
- Khatereh Saei Arezoumand
- Department of Biochemistry and Medical Genetics, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada
| | - Chris-Tiann Roberts
- Department of Biochemistry and Medical Genetics, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada
| | - Mojgan Rastegar
- Department of Biochemistry and Medical Genetics, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada
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Moore R, Poulsen J, Reardon L, Samples-Morris C, Simmons H, Ramsey KM, Whatley ML, Lane JB. Managing Gastrointestinal Symptoms Resulting from Treatment with Trofinetide for Rett Syndrome: Caregiver and Nurse Perspectives. Adv Ther 2024; 41:1305-1317. [PMID: 38378975 PMCID: PMC10960750 DOI: 10.1007/s12325-024-02782-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 01/04/2024] [Indexed: 02/22/2024]
Abstract
Rett syndrome (RTT) is a rare genetic neurodevelopmental disorder mainly affecting female individuals. Trofinetide was recently approved as the first treatment for RTT, largely on the basis of results from the phase 3 LAVENDER trial, in which trofinetide showed improvements in core symptoms of RTT compared with placebo. However, gastrointestinal (GI) symptoms such as diarrhea and vomiting were commonly reported side effects, and taste was also a reported issue. The objective of this article is to describe the perspectives of five caregivers of girls in trofinetide clinical trials as well as those of three nurse trial coordinators, with a focus on management of GI symptoms of trofinetide treatment.Audio Abstract available for this article. Audio Abstract: Jane Lane provides an overview and discusses key findings of the article titled "Managing Gastrointestinal Symptoms Resulting from Treatment with Trofinetide for Rett Syndrome: Caregiver and Nurse Perspectives." (MP4 83274 KB).
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Affiliation(s)
| | | | | | | | | | - Keri M Ramsey
- Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, AZ, USA
| | | | - Jane B Lane
- University of Alabama at Birmingham, Birmingham, AL, USA.
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Darwish M, Passarell J, Youakim JM, Bradley H, Bishop KM. Exposure-Response Efficacy Modeling to Support Trofinetide Dosing in Individuals with Rett Syndrome. Adv Ther 2024; 41:1462-1480. [PMID: 38363467 PMCID: PMC10960884 DOI: 10.1007/s12325-024-02796-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 01/19/2024] [Indexed: 02/17/2024]
Abstract
INTRODUCTION Trofinetide was recently approved for the treatment of Rett syndrome (RTT) on the basis of the efficacy and safety findings of the phase 3 LAVENDER study, which used a body weight-based dosing regimen. Exposure-response (E-R) efficacy modeling was used to characterize relationships between trofinetide exposure measures (maximum drug concentration and area under the concentration-time curve for the dosing interval of 0-12 h [AUC0-12]) and efficacy endpoints in RTT clinical studies to support the trofinetide dosing regimen. METHODS Efficacy endpoints were modeled using trofinetide exposure measures predicted from the population pharmacokinetic model and Bayesian estimates. The analysis population for each E-R model comprised individuals receiving placebo or trofinetide who had available trofinetide exposure measures. Efficacy endpoints were scores from the Rett Syndrome Behaviour Questionnaire (RSBQ), the Clinical Global Impression-Improvement, the Communication and Symbolic Behavior Scales Developmental Profile™ Infant-Toddler Checklist (CSBS-DP-IT) Social Composite, and the Rett Syndrome Clinician Rating of Ability to Communicate Choices (RTT-COMC). RESULTS Higher trofinetide exposure was associated with improvements in RSBQ, CSBS-DP-IT Social Composite, and RTT-COMC scores. Assuming target trofinetide AUC0-12 values of 800-1200 μg·h/mL, the reductions in RSBQ total scores at week 12 were approximately five- to seven-fold greater with trofinetide (range 3.55-4.94) versus placebo (0.76). Significant E-R relationships were also found for the CSBS-DP-IT Social Composite and RTT-COMC scores. CONCLUSION E-R efficacy modeling demonstrated significant relationships between trofinetide exposure and RSBQ, CSBS-DP-IT Social Composite, and RTT-COMC scores. Trofinetide is efficacious within the target exposure range, supporting the approved dosing regimen for trofinetide. TRIAL REGISTRATION NCT01703533, NCT02715115, NCT04181723.
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Affiliation(s)
- Mona Darwish
- Acadia Pharmaceuticals Inc., 12830 El Camino Real, Suite 400, San Diego, CA, 92130, USA.
| | - Julie Passarell
- Cognigen Corporation (a Simulations Plus Company), Buffalo, NY, USA
| | - James M Youakim
- Acadia Pharmaceuticals Inc., 12830 El Camino Real, Suite 400, San Diego, CA, 92130, USA
| | - Heather Bradley
- Acadia Pharmaceuticals Inc., 12830 El Camino Real, Suite 400, San Diego, CA, 92130, USA
| | - Kathie M Bishop
- Acadia Pharmaceuticals Inc., 12830 El Camino Real, Suite 400, San Diego, CA, 92130, USA
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Abbas A, Fayoud AM, El Din Moawad MH, Hamad AA, Hamouda H, Fouad EA. Safety and efficacy of trofinetide in Rett syndrome: a systematic review and meta-analysis of randomized controlled trials. BMC Pediatr 2024; 24:206. [PMID: 38521908 PMCID: PMC10960414 DOI: 10.1186/s12887-024-04526-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 01/01/2024] [Indexed: 03/25/2024] Open
Abstract
INTRODUCTION Rett syndrome is a rare genetic neurodevelopmental disorder that predominantly impacts females. It presents with loss of acquired skills, impaired communication, and stereotypic hand movements. Given the limited treatment options for Rett syndrome, there is a dire need for effective interventions. OBJECTIVE To evaluate the safety and efficacy of trofinetide in Randomized Controlled Trials (RCTs) that report on Rett syndrome patients. METHODS We identified 109 articles from four databases (Scopus, PubMed, Web of Science, and Cochrane CENTRAL). After removing the duplicates, we narrowed them down to 59 articles for further assessment. We included RCTs that evaluated the efficacy and safety of trofinetide in patients with Rett syndrome. Three studies were eligible for inclusion. Two independent reviewers evaluated the identified studies' titles, abstracts, and full texts, extracting pertinent data. We assessed the quality of the studies using the Cochrane Risk of Bias (RoB) 2.0 tool. We then conducted a meta-analysis using the fixed effects model in the case of insignificant heterogeneity; otherwise, we used the random effects model. Based on the nature of the outcome, we analyzed the mean difference or the odds ratio. Analysis was conducted using RevMan version 5.3. RESULTS Among the analyzed outcomes in 181 patients in the trofinetide group and 134 patients in the placebo group, significant improvement in Rett Syndrome Behavior Questionnaire (RSBQ) scores was observed at 200 mg dosage (overall mean difference: -3.53, p = 0.001). Clinical Global Impression-Improvement (CGI-I) scores improved considerably at 200 mg dosage (overall mean difference: -0.34, p < 0.0001). No substantial changes were observed in Motor Behavioral Assessment (MBA) or Top 3 Caregiver Concerns. We evaluated Treatment Emergent Adverse Events (TEAEs) across the various dosages and noted significant associations with diarrhea (200 mg), vomiting (200 mg), and irritability (200 mg). However, we did not find a significant association between any of the dosages and the incidence of decreased appetite. CONCLUSION Trofinetide demonstrated potential in improving RSBQ and CGI-I scores at 200 mg dosage. Although no substantial changes were found in MBA and top 3 caregiver concerns. Adverse events were linked to specific dosages.
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Affiliation(s)
- Abdallah Abbas
- Faculty of Medicine, Al-Azhar University, Damietta, Egypt.
| | - Aya M Fayoud
- Faculty of Pharmacy, Kafr El sheik university, Kafr El Sheik, Egypt
| | - Mostafa Hossam El Din Moawad
- Faculty of Pharmacy Clinical Department, Alexandria University, Alexandria, Egypt
- Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | | | - Heba Hamouda
- Faculty of Medicine, Menoufia University, Menoufia, Egypt
| | - Eman A Fouad
- Department of Pediatrics, Ubbo-Emmius-Klinik, Aurich, Germany
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Neul JL, Percy AK, Benke TA, Berry-Kravis EM, Glaze DG, Peters SU, Marsh ED, An D, Bishop KM, Youakim JM. Trofinetide Treatment Demonstrates a Benefit Over Placebo for the Ability to Communicate in Rett Syndrome. Pediatr Neurol 2024; 152:63-72. [PMID: 38232652 DOI: 10.1016/j.pediatrneurol.2023.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 10/27/2023] [Accepted: 11/18/2023] [Indexed: 01/19/2024]
Abstract
BACKGROUND Trofinetide was approved by the US Food and Drug Administration for the treatment of Rett syndrome (RTT) in March 2023. Benefiting the ability to communicate in RTT is often identified as the most important caregiver goal for new therapies. This analysis reports the communication-related end points from the phase 3 LAVENDER study of trofinetide in RTT. METHODS Females with RTT, aged five to 20 years, were randomized 1:1 to trofinetide or placebo for 12 weeks. Secondary efficacy end points related to communication were based on change from baseline to week 12 and included the caregiver-rated Communication and Symbolic Behavior Scales Developmental Profile™ Infant-Toddler Checklist (CSBS-DP-IT) Social Composite score (key secondary end point; scores ranged from 0 to 26 [higher scores indicated better communication]) and novel clinician rating scales (0 [normal] to 7 [severe impairment]) measuring the ability to communicate choices nonverbally (RTT-COMC) and verbally (RTT-VCOM). RESULTS Trofinetide demonstrated a statistically significant difference versus placebo for the CSBS-DP-IT Social Composite score (least squares mean [LSM] difference = 1.0; 95% confidence interval [CI], 0.3 to 1.7; P = 0.0064; Cohen's d effect size = 0.43) and a nominally significant difference for the RTT-COMC (LSM difference: -0.3; 95% CI, -0.6 to -0.0; P = 0.0257; Cohen's d effect size = 0.36). As expected, there was no difference for the RTT-VCOM. CONCLUSIONS Significant treatment benefit for trofinetide versus placebo was observed in scales measuring the ability to communicate. These scales may be appropriate for future clinical studies in RTT and other neurodevelopmental disorders.
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Affiliation(s)
- Jeffrey L Neul
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Alan K Percy
- University of Alabama at Birmingham, Birmingham, Alabama
| | - Timothy A Benke
- Children's Hospital of Colorado, University of Colorado School of Medicine, Aurora, Colorado
| | | | - Daniel G Glaze
- Texas Children's Hospital, Baylor College of Medicine, Houston, Texas
| | - Sarika U Peters
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Eric D Marsh
- Children's Hospital of Philadelphia, Philadelphia, Pennsylvania; University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Di An
- Acadia Pharmaceuticals Inc, San Diego, California
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Amin S, Ruban-Fell B, Newell I, Evans J, Vyas K, Nortvedt C, Chin RF. Treatment guidelines for rare, early-onset conditions associated with epileptic seizures: a literature review on Rett syndrome and tuberous sclerosis complex. Orphanet J Rare Dis 2024; 19:89. [PMID: 38409029 PMCID: PMC10895812 DOI: 10.1186/s13023-023-02994-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 12/13/2023] [Indexed: 02/28/2024] Open
Abstract
BACKGROUND Rett syndrome (RTT) and tuberous sclerosis complex (TSC) are two rare disorders presenting with a range of different epileptic seizures. Seizure management requires careful therapy selection, thereby necessitating development of high-quality treatment guidelines. This targeted literature review (TLR) aimed to characterise country-specific and international treatment guidelines available for pharmacological management of seizures in RTT and TSC. METHODS A TLR was performed between 25-Jan and 11-Mar 2021. Manual searches of online rare disease and guideline databases, and websites of national heath technology assessment bodies were conducted for the following countries: Australia, Canada, France, Germany, Israel, Italy, Japan, Spain, Switzerland, UK, and US as defined by pre-specified eligibility criteria. Search terms were developed for each condition and translated into local languages where appropriate. Eligible publications were defined as guidelines/guidance reporting pharmacological management of seizures in patients with RTT and TSC. Guideline development methodology, geographical focus, author information and treatment recommendations were extracted from guidelines. An author map was generated using R version 3.5.1 to visualise extent of collaboration between authors. RESULTS 24 total guidelines were included, of which three and six contained only recommendations for RTT and TSC, respectively (some provided recommendations for ≥ 1 condition). Guideline development processes were poorly described (50% [12 guidelines] had unclear/absent literature review methodologies); reported methodologies were variable, including systematic literature reviews (SLRs)/TLRs and varying levels of expert consultation. Most (83% [20/24]) were country-specific, with guideline authors predominantly publishing in contained national groups; four guidelines were classified as 'International,' linking author groups in the US, UK, Italy and France. High levels of heterogeneity were observed in the availability of treatment recommendations across indications, with 13 and 67 recommendations found for RTT and TSC, respectively. For RTT, all treatment recommendations were positive and sodium valproate had the highest number of positive recommendations (Khwaja, Sahin (2011) Curr Opin Pediatr 23(6):633-9). All TSC treatments (21 medications) received either exclusively negative (National Organization for Rare Disorders (2019)) or positive (Chu-Shore et al. (2010) Epilepsia 51(7):1236-41) recommendations; vigabatrin received the highest number of positive recommendations (Kaur, Christodoulou (2019)). CONCLUSIONS This review highlights the need for the development of international high-quality and comprehensive consensus-based guidance for the management of seizures with pharmacological therapy in RTT and TSC. TRIAL REGISTRATION Not applicable.
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Affiliation(s)
- S Amin
- Bristol Royal Hospital for Children, Research and Education Centre, Upper Maudlin St, Bristol, BS2 8AE, UK.
| | | | | | - J Evans
- Costello Medical, Cambridge, UK
| | - K Vyas
- GW Pharmaceuticals, London, UK
| | | | - R F Chin
- Royal Hospital for Children and Young People, Edinburgh, UK
- Muir Maxwell Epilepsy Centre, Centre for Clinical Brain Sciences, Edinburgh, UK
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Desnous B, Beretti T, Muller N, Neveu J, Villeneuve N, Lépine A, Daquin G, Milh M. Efficacy and tolerance of cannabidiol in the treatment of epilepsy in patients with Rett syndrome. Epilepsia Open 2024; 9:397-403. [PMID: 37485779 PMCID: PMC10839357 DOI: 10.1002/epi4.12796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 07/20/2023] [Indexed: 07/25/2023] Open
Abstract
We aim to assess the efficacy and tolerance of cannabidiol as adjunctive therapy for Rett syndrome (RTT) patients with epilepsy. We conducted a longitudinal observational study through a monocentric cohort of 46 patients with RTT. Patients were recruited from March 2020 to October 2022 and were treated with Epidyolex® (cannabidiol, CBD, 100 mg/mL oral solution). In our cohort, 26 patients had associated epilepsy (26/46 [56%]), and 10/26 (38%) were treated with CBD, in combination with clobazam in 50% of cases. The median dose at their last follow-up was 15 mg/kg/day. The median treatment duration was 13 months (range: 1-32 months). CBD reduced the incidence of seizures in seven out of 10 patients (70%) with one seizure-free patient, two patients with a reduction of seizures of more than 75%, and four patients with a decrease of more than 50%. No aggravation of symptoms or adverse effects were observed. Only one patient experienced a transitory drooling and somnolence episode at the CBD initiation. Half of the patients showed a reduction in agitation and/or anxiety attacks, and an improvement in spasticity was reported in 4/10 (40%) of patients. CBD appears to have potential therapeutic value for the treatment of drug-resistant epilepsy in Rett syndrome. CBD is well tolerated and, when used in combination with clobazam, may increase the effectiveness of clobazam alone.
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Affiliation(s)
- Béatrice Desnous
- Pediatric Neurology DepartmentTimone Enfant, APHMMarseilleFrance
| | - Thibault Beretti
- Pediatric Neurology DepartmentTimone Enfant, APHMMarseilleFrance
| | - Nathan Muller
- Pediatric Neurology DepartmentTimone Enfant, APHMMarseilleFrance
| | | | | | - Anne Lépine
- Pediatric Neurology DepartmentTimone Enfant, APHMMarseilleFrance
| | - Géraldine Daquin
- Epileptology and Cerebral Rhythmology DepartmentTimone Adulte, APHMMarseilleFrance
| | - Mathieu Milh
- Pediatric Neurology DepartmentTimone Enfant, APHMMarseilleFrance
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Musokhranova U, Grau C, Vergara C, Rodríguez-Pascau L, Xiol C, Castells AA, Alcántara S, Rodríguez-Pombo P, Pizcueta P, Martinell M, García-Cazorla A, Oyarzábal A. Mitochondrial modulation with leriglitazone as a potential treatment for Rett syndrome. J Transl Med 2023; 21:756. [PMID: 37884937 PMCID: PMC10601217 DOI: 10.1186/s12967-023-04622-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND Rett syndrome is a neuropediatric disease occurring due to mutations in MECP2 and characterized by a regression in the neuronal development following a normal postnatal growth, which results in the loss of acquired capabilities such as speech or purposeful usage of hands. While altered neurotransmission and brain development are the center of its pathophysiology, alterations in mitochondrial performance have been previously outlined, shaping it as an attractive target for the disease treatment. METHODS We have thoroughly described mitochondrial performance in two Rett models, patients' primary fibroblasts and female Mecp2tm1.1Bird-/+ mice brain, discriminating between different brain areas. The characterization was made according to their bioenergetics function, oxidative stress, network dynamics or ultrastructure. Building on that, we have studied the effect of leriglitazone, a PPARγ agonist, in the modulation of mitochondrial performance. For that, we treated Rett female mice with 75 mg/kg/day leriglitazone from weaning until sacrifice at 7 months, studying both the mitochondrial performance changes and their consequences on the mice phenotype. Finally, we studied its effect on neuroinflammation based on the presence of reactive glia by immunohistochemistry and through a cytokine panel. RESULTS We have described mitochondrial alterations in Rett fibroblasts regarding both shape and bioenergetic functions, as they displayed less interconnected and shorter mitochondria and reduced ATP production along with increased oxidative stress. The bioenergetic alterations were recalled in Rett mice models, being especially significant in cerebellum, already detectable in pre-symptomatic stages. Treatment with leriglitazone recovered the bioenergetic alterations both in Rett fibroblasts and female mice and exerted an anti-inflammatory effect in the latest, resulting in the amelioration of the mice phenotype both in general condition and exploratory activity. CONCLUSIONS Our studies confirm the mitochondrial dysfunction in Rett syndrome, setting the differences through brain areas and disease stages. Its modulation through leriglitazone is a potential treatment for this disorder, along with other diseases with mitochondrial involvement. This work constitutes the preclinical necessary evidence to lead to a clinical trial.
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Affiliation(s)
- Uliana Musokhranova
- Synaptic Metabolism and Personalized Therapies Lab, Department of Neurology and MetabERN, Institut de Recerca Sant Joan de Déu, 39-57 Santa Rosa Street, Esplugues de Llobregat , 08950, Barcelona, Spain
| | - Cristina Grau
- Synaptic Metabolism and Personalized Therapies Lab, Department of Neurology and MetabERN, Institut de Recerca Sant Joan de Déu, 39-57 Santa Rosa Street, Esplugues de Llobregat , 08950, Barcelona, Spain
| | | | | | - Clara Xiol
- Department of Medical Genetics, Institut de Recerca Pediàtrica, Hospital Sant Joan de Déu, Barcelona, Spain
| | - Alba A Castells
- Neural Development Lab, Departament de Patologia i Terapèutica Experimental, Institut de Neurociències, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Soledad Alcántara
- Neural Development Lab, Departament de Patologia i Terapèutica Experimental, Institut de Neurociències, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Pilar Rodríguez-Pombo
- Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular Severo Ochoa, CBM-CSIC, Departamento de Biología Molecular, Institute for Molecular Biology-IUBM, Universidad Autónoma Madrid, IDIPAZ, Madrid, Spain
- CIBERER-Spanish Biomedical Research Centre in Rare Diseases, Madrid, Spain
| | | | - Marc Martinell
- Minoryx Therapeutics BE S.A., Gosselies, Charleroi, Belgium
- Minoryx Therapeutics S.L., Barcelona, Spain
| | - Angels García-Cazorla
- Synaptic Metabolism and Personalized Therapies Lab, Department of Neurology and MetabERN, Institut de Recerca Sant Joan de Déu, 39-57 Santa Rosa Street, Esplugues de Llobregat , 08950, Barcelona, Spain
- CIBERER-Spanish Biomedical Research Centre in Rare Diseases, Madrid, Spain
| | - Alfonso Oyarzábal
- Synaptic Metabolism and Personalized Therapies Lab, Department of Neurology and MetabERN, Institut de Recerca Sant Joan de Déu, 39-57 Santa Rosa Street, Esplugues de Llobregat , 08950, Barcelona, Spain.
- CIBERER-Spanish Biomedical Research Centre in Rare Diseases, Madrid, Spain.
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Parent H, Ferranti A, Niswender C. Trofinetide: a pioneering treatment for Rett syndrome. Trends Pharmacol Sci 2023; 44:740-741. [PMID: 37460385 PMCID: PMC10529922 DOI: 10.1016/j.tips.2023.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 06/23/2023] [Accepted: 06/23/2023] [Indexed: 08/09/2023]
Affiliation(s)
- Harrison Parent
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, USA
| | - Anthony Ferranti
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, USA
| | - Colleen Niswender
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA; Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, USA; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA.
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Neul JL, Percy AK, Benke TA, Berry-Kravis EM, Glaze DG, Marsh ED, Lin T, Stankovic S, Bishop KM, Youakim JM. Trofinetide for the treatment of Rett syndrome: a randomized phase 3 study. Nat Med 2023; 29:1468-1475. [PMID: 37291210 PMCID: PMC10287558 DOI: 10.1038/s41591-023-02398-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 05/12/2023] [Indexed: 06/10/2023]
Abstract
Rett syndrome is a rare, genetic neurodevelopmental disorder. Trofinetide is a synthetic analog of glycine-proline-glutamate, the N-terminal tripeptide of the insulin-like growth factor 1 protein, and has demonstrated clinical benefit in phase 2 studies in Rett syndrome. In this phase 3 study ( https://clinicaltrials.gov identifier NCT04181723 ), females with Rett syndrome received twice-daily oral trofinetide (n = 93) or placebo (n = 94) for 12 weeks. For the coprimary efficacy endpoints, least squares mean (LSM) change from baseline to week 12 in the Rett Syndrome Behaviour Questionnaire for trofinetide versus placebo was -4.9 versus -1.7 (P = 0.0175; Cohen's d effect size, 0.37), and LSM Clinical Global Impression-Improvement at week 12 was 3.5 versus 3.8 (P = 0.0030; effect size, 0.47). For the key secondary efficacy endpoint, LSM change from baseline to week 12 in the Communication and Symbolic Behavior Scales Developmental Profile Infant-Toddler Checklist Social Composite score was -0.1 versus -1.1 (P = 0.0064; effect size, 0.43). Common treatment-emergent adverse events included diarrhea (80.6% for trofinetide versus 19.1% for placebo), which was mostly mild to moderate in severity. Significant improvement for trofinetide compared with placebo was observed for the coprimary efficacy endpoints, suggesting that trofinetide provides benefit in treating the core symptoms of Rett syndrome.
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Affiliation(s)
- Jeffrey L Neul
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Alan K Percy
- University of Alabama at Birmingham, Birmingham, AL, USA
| | - Timothy A Benke
- Children's Hospital of Colorado and University of Colorado School of Medicine, Aurora, CO, USA
| | | | - Daniel G Glaze
- Texas Children's Hospital and Baylor College of Medicine, Houston, TX, USA
| | - Eric D Marsh
- Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Tim Lin
- Acadia Pharmaceuticals Inc., San Diego, CA, USA
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Harris E. Trofinetide Receives FDA Approval as First Drug for Rett Syndrome. JAMA 2023; 329:1142. [PMID: 36947078 DOI: 10.1001/jama.2023.4003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
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12
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Smith M, Arthur B, Cikowski J, Holt C, Gonzalez S, Fisher NM, Vermudez SAD, Lindsley CW, Niswender CM, Gogliotti RG. Clinical and Preclinical Evidence for M 1 Muscarinic Acetylcholine Receptor Potentiation as a Therapeutic Approach for Rett Syndrome. Neurotherapeutics 2022; 19:1340-1352. [PMID: 35670902 PMCID: PMC9587166 DOI: 10.1007/s13311-022-01254-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2022] [Indexed: 12/04/2022] Open
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder that is characterized by developmental regression, loss of communicative ability, stereotyped hand wringing, cognitive impairment, and central apneas, among many other symptoms. RTT is caused by loss-of-function mutations in a methyl-reader known as methyl-CpG-binding protein 2 (MeCP2), a protein that links epigenetic changes on DNA to larger chromatin structure. Historically, target identification for RTT has relied heavily on Mecp2 knockout mice; however, we recently adopted the alternative approach of performing transcriptional profiling in autopsy samples from RTT patients. Through this mechanism, we identified muscarinic acetylcholine receptors (mAChRs) as potential therapeutic targets. Here, we characterized a cohort of 40 temporal cortex samples from individuals with RTT and quantified significantly decreased levels of the M1, M2, M3, and M5 mAChRs subtypes relative to neurotypical controls. Of these four subtypes, M1 expression demonstrated a linear relationship with MeCP2 expression, such that M1 levels were only diminished in contexts where MeCP2 was also significantly decreased. Further, we show that M1 potentiation with the positive allosteric modulator (PAM) VU0453595 (VU595) rescued social preference, spatial memory, and associative memory deficits, as well as decreased apneas in Mecp2+/- mice. VU595's efficacy on apneas in Mecp2+/- mice was mediated by the facilitation of the transition from inspiration to expiration. Molecular analysis correlated rescue with normalized global gene expression patterns in the brainstem and hippocampus, as well as increased Gsk3β inhibition and NMDA receptor trafficking. Together, these data suggest that M1 PAMs could represent a new class of RTT therapeutics.
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Affiliation(s)
- Mackenzie Smith
- Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago, Maywood, IL, 60153, USA
- Edward Hines Jr. VA Hospital, Hines, IL, 60141, USA
| | - Bright Arthur
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Jakub Cikowski
- Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago, Maywood, IL, 60153, USA
- Edward Hines Jr. VA Hospital, Hines, IL, 60141, USA
| | - Calista Holt
- Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago, Maywood, IL, 60153, USA
- Edward Hines Jr. VA Hospital, Hines, IL, 60141, USA
| | - Sonia Gonzalez
- Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago, Maywood, IL, 60153, USA
- Edward Hines Jr. VA Hospital, Hines, IL, 60141, USA
| | - Nicole M Fisher
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Sheryl Anne D Vermudez
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, 37232, USA
- Department of Chemistry, Vanderbilt University, Nashville, TN, 37232, USA
| | - Colleen M Niswender
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA
- Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN, 37232, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, 37232, USA
| | - Rocco G Gogliotti
- Department of Molecular Pharmacology and Neuroscience, Loyola University Chicago, Maywood, IL, 60153, USA.
- Edward Hines Jr. VA Hospital, Hines, IL, 60141, USA.
- Department of Pharmacology, Vanderbilt University, Nashville, TN, 37232, USA.
- Warren Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, 37232, USA.
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13
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Steinkellner H, Kempaiah P, Beribisky AV, Pferschy S, Etzler J, Huber A, Sarne V, Neuhaus W, Kuttke M, Bauer J, Arunachalam JP, Christodoulou J, Dressel R, Mildner A, Prinz M, Laccone F. TAT-MeCP2 protein variants rescue disease phenotypes in human and mouse models of Rett syndrome. Int J Biol Macromol 2022; 209:972-983. [PMID: 35460749 DOI: 10.1016/j.ijbiomac.2022.04.080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/08/2022] [Accepted: 04/11/2022] [Indexed: 01/02/2023]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder caused by pathogenic variants leading to functional impairment of the MeCP2 protein. Here, we used purified recombinant MeCP2e1 and MeCP2e2 protein variants fused to a TAT protein transduction domain (PTD) to evaluate their transduction ability into RTT patient-derived fibroblasts and the ability to carry out their cellular function. We then assessed their transduction ability and therapeutic effects in a RTT mouse model. In vitro, TAT-MeCP2e2-eGFP reversed the pathological hyperacetylation of histones H3K9 and H4K16, a hallmark of abolition of MeCP2 function. In vivo, intraperitoneal administration of TAT-MeCP2e1 and TAT-MeCP2e2 extended the lifespan of Mecp2-/y mice by >50%. This was accompanied by rescue of hippocampal CA2 neuron size in animals treated with TAT-MeCP2e1. Taken together, these findings provide a strong indication that recombinant TAT-MeCP2 can reach mouse brains following peripheral injection and can ameliorate the phenotype of RTT mouse models. Thus, our study serves as a first step in the development of a potentially novel RTT therapy.
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Affiliation(s)
- Hannes Steinkellner
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Prakasha Kempaiah
- Institute for Human Genetics, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany; Division of Infectious Diseases, Mayo Clinic, Jacksonville, FL, USA
| | - Alexander V Beribisky
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Sandra Pferschy
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Julia Etzler
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Anna Huber
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria; Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences (PhaNuSpo), University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Victoria Sarne
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria
| | - Winfried Neuhaus
- AIT Austrian Institute of Technology GmbH, Competence Center Molecular Diagnostics, 1210 Vienna, Austria
| | - Mario Kuttke
- Institute for Vascular Biology, Center for Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - Jan Bauer
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jayamuruga P Arunachalam
- Institute for Human Genetics, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany; Division of Infectious Diseases, Mayo Clinic, Jacksonville, FL, USA; Department of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, ON, Canada
| | - John Christodoulou
- Murdoch Children's Research Institute and Department of Paediatrics, University of Melbourne, Discipline of Child & Adolescent Health, Sydney Medical School, Australia
| | - Ralf Dressel
- Department of Cellular and Molecular Immunology, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany
| | - Alexander Mildner
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Marco Prinz
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany; Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Franco Laccone
- Center for Pathobiochemistry and Genetics, Institute of Medical Genetics, Medical University of Vienna, 1090 Vienna, Austria; Institute for Human Genetics, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany; Department of Cellular and Molecular Immunology, Georg August University, Universitätsmedizin Göttingen, 37073 Göttingen, Germany.
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14
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Ribeiro MC, MacDonald JL. Vitamin D modulates cortical transcriptome and behavioral phenotypes in an Mecp2 heterozygous Rett syndrome mouse model. Neurobiol Dis 2022; 165:105636. [PMID: 35091041 PMCID: PMC8864637 DOI: 10.1016/j.nbd.2022.105636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 12/14/2022] Open
Abstract
Rett syndrome (RTT) is an X-linked neurological disorder caused by mutations in the transcriptional regulator MECP2. Mecp2 loss-of-function leads to the disruption of many cellular pathways, including aberrant activation of the NF-κB pathway. Genetically attenuating the NF-κB pathway in Mecp2-null mice ameliorates hallmark phenotypes of RTT, including reduced dendritic complexity, raising the question of whether NF-κB pathway inhibitors could provide a therapeutic avenue for RTT. Vitamin D is a known inhibitor of NF-κB signaling; further, vitamin D deficiency is prevalent in RTT patients and male Mecp2-null mice. We previously demonstrated that vitamin D rescues the aberrant NF-κB activity and reduced neurite outgrowth of Mecp2-knockdown cortical neurons in vitro, and that dietary vitamin D supplementation rescues decreased dendritic complexity and soma size of neocortical projection neurons in both male hemizygous Mecp2-null and female heterozygous mice in vivo. Here, we have identified over 200 genes whose dysregulated expression in the Mecp2+/- cortex is modulated by dietary vitamin D. Genes normalized with vitamin D supplementation are involved in dendritic complexity, synapses, and neuronal projections, suggesting that the rescue of their expression could underpin the rescue of neuronal morphology. Further, there is a disruption in the homeostasis of the vitamin D synthesis pathway in Mecp2+/- mice, and motor and anxiety-like behavioral phenotypes in Mecp2+/- mice correlate with circulating vitamin D levels. Thus, our data indicate that vitamin D modulates RTT pathology and its supplementation could provide a simple and cost-effective partial therapeutic for RTT.
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Affiliation(s)
- Mayara C Ribeiro
- Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, NY 13244, United States of America
| | - Jessica L MacDonald
- Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, NY 13244, United States of America.
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15
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Wu Y, Cui N, Xing H, Zhong W, Arrowood C, Johnson CM, Jiang C. In vivo evidence for the cellular basis of central hypoventilation of Rett syndrome and pharmacological correction in the rat model. J Cell Physiol 2021; 236:8082-8098. [PMID: 34077559 DOI: 10.1002/jcp.30462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 04/13/2021] [Accepted: 05/08/2021] [Indexed: 12/29/2022]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder caused mostly by mutations in the MECP2 gene. RTT patients show periodical hypoventilation attacks. The breathing disorder contributing to the high incidence of sudden death is thought to be due to depressed central inspiratory (I) activity via unknown cellular processes. Demonstration of such processes may lead to targets for pharmacological control of the RTT-type hypoventilation. We performed in vivo recordings from medullary respiratory neurons on the RTT rat model. To our surprise, both I and expiratory (E) neurons in the ventral respiratory column (VRC) increased their firing activity in Mecp2-null rats with severe hypoventilation. These I neurons including E-I phase-spanning and other I neurons remained active during apneas. Consistent with enhanced central I drive, ectopic phrenic discharges during expiration as well as apnea were observed in the Mecp2-null rats. Considering the increased I neuronal firing and ectopic phrenic activity, the RTT-type hypoventilation does not seem to be caused by depression in central I activity, neither reduced medullary I premotor output. This as well as excessive E neuronal firing as shown in our previous studies suggests inadequate synaptic inhibition for phase transition. We found that the abnormal respiratory neuronal firing, ectopic phrenic discharge as well as RTT-type hypoventilation all can be corrected by enhancing GABAergic inhibition. More strikingly, Mecp2-null rats reaching humane endpoints with severe hypoventilation can be rescued by GABAergic augmentation. Thus, defective GABAergic inhibition among respiratory neurons is likely to play a role in the RTT-type hypoventilation, which can be effectively controlled with pharmacological agents.
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Affiliation(s)
- Yang Wu
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Ningren Cui
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Hao Xing
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Weiwei Zhong
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | - Colin Arrowood
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
| | | | - Chun Jiang
- Department of Biology, Georgia State University, Atlanta, Georgia, USA
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16
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Urbinati C, Cosentino L, Germinario EAP, Valenti D, Vigli D, Ricceri L, Laviola G, Fiorentini C, Vacca RA, Fabbri A, De Filippis B. Treatment with the Bacterial Toxin CNF1 Selectively Rescues Cognitive and Brain Mitochondrial Deficits in a Female Mouse Model of Rett Syndrome Carrying a MeCP2-Null Mutation. Int J Mol Sci 2021; 22:6739. [PMID: 34201747 PMCID: PMC8269120 DOI: 10.3390/ijms22136739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/25/2021] [Accepted: 06/14/2021] [Indexed: 12/11/2022] Open
Abstract
Rett syndrome (RTT) is a rare neurological disorder caused by mutations in the X-linked MECP2 gene and a major cause of intellectual disability in females. No cure exists for RTT. We previously reported that the behavioural phenotype and brain mitochondria dysfunction are widely rescued by a single intracerebroventricular injection of the bacterial toxin CNF1 in a RTT mouse model carrying a truncating mutation of the MeCP2 gene (MeCP2-308 mice). Given the heterogeneity of MECP2 mutations in RTT patients, we tested the CNF1 therapeutic efficacy in a mouse model carrying a null mutation (MeCP2-Bird mice). CNF1 selectively rescued cognitive defects, without improving other RTT-related behavioural alterations, and restored brain mitochondrial respiratory chain complex activity in MeCP2-Bird mice. To shed light on the molecular mechanisms underlying the differential CNF1 effects on the behavioural phenotype, we compared treatment effects on relevant signalling cascades in the brain of the two RTT models. CNF1 provided a significant boost of the mTOR activation in MeCP2-308 hippocampus, which was not observed in the MeCP2-Bird model, possibly explaining the differential effects of CNF1. These results demonstrate that CNF1 efficacy depends on the mutation beared by MeCP2-mutated mice, stressing the need of testing potential therapeutic approaches across RTT models.
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Affiliation(s)
- Chiara Urbinati
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (C.U.); (L.C.); (D.V.); (L.R.); (G.L.)
| | - Livia Cosentino
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (C.U.); (L.C.); (D.V.); (L.R.); (G.L.)
| | - Elena Angela Pia Germinario
- Department of Cardiovascular, Endocrine-Metabolic Diseases and Aging, Istituto Superiore di Sanità, 00161 Rome, Italy; (E.A.P.G.); (A.F.)
| | - Daniela Valenti
- Bioenergetics and Molecular Biotechnologies, Institute of Biomembranes, National Council of Research, 70126 Bari, Italy; (D.V.); (R.A.V.)
| | - Daniele Vigli
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (C.U.); (L.C.); (D.V.); (L.R.); (G.L.)
| | - Laura Ricceri
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (C.U.); (L.C.); (D.V.); (L.R.); (G.L.)
| | - Giovanni Laviola
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (C.U.); (L.C.); (D.V.); (L.R.); (G.L.)
| | - Carla Fiorentini
- Association for Research on Integrative Oncology Therapies (ARTOI), 00165 Rome, Italy;
| | - Rosa Anna Vacca
- Bioenergetics and Molecular Biotechnologies, Institute of Biomembranes, National Council of Research, 70126 Bari, Italy; (D.V.); (R.A.V.)
| | - Alessia Fabbri
- Department of Cardiovascular, Endocrine-Metabolic Diseases and Aging, Istituto Superiore di Sanità, 00161 Rome, Italy; (E.A.P.G.); (A.F.)
| | - Bianca De Filippis
- Center for Behavioral Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; (C.U.); (L.C.); (D.V.); (L.R.); (G.L.)
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17
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Pizzamiglio L, Focchi E, Cambria C, Ponzoni L, Ferrara S, Bifari F, Desiato G, Landsberger N, Murru L, Passafaro M, Sala M, Matteoli M, Menna E, Antonucci F. The DNA repair protein ATM as a target in autism spectrum disorder. JCI Insight 2021; 6:133654. [PMID: 33373327 PMCID: PMC7934840 DOI: 10.1172/jci.insight.133654] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 12/16/2020] [Indexed: 12/20/2022] Open
Abstract
Impairment of the GABAergic system has been reported in epilepsy, autism, attention deficit hyperactivity disorder, and schizophrenia. We recently demonstrated that ataxia telangiectasia mutated (ATM) directly shapes the development of the GABAergic system. Here, we show for the first time to our knowledge how the abnormal expression of ATM affects the pathological condition of autism. We exploited 2 different animal models of autism, the methyl CpG binding protein 2-null (Mecp2y/-) mouse model of Rett syndrome and mice prenatally exposed to valproic acid, and found increased ATM levels. Accordingly, treatment with the specific ATM kinase inhibitor KU55933 (KU) normalized molecular, functional, and behavioral defects in these mouse models, such as (a) delayed GABAergic development, (b) hippocampal hyperexcitability, (c) low cognitive performances, and (d) social impairments. Mechanistically, we demonstrate that KU administration to WT hippocampal neurons leads to (a) higher early growth response 4 activity on Kcc2b promoter, (b) increased expression of Mecp2, and (c) potentiated GABA transmission. These results provide evidence and molecular substrates for the pharmacological development of ATM inhibition in autism spectrum disorders.
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Affiliation(s)
- Lara Pizzamiglio
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Elisa Focchi
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Clara Cambria
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | | | - Silvia Ferrara
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Francesco Bifari
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Genni Desiato
- Humanitas Clinical and Research Center – IRCCS, Rozzano, Milan, Italy
| | - Nicoletta Landsberger
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
| | - Luca Murru
- Institute of Neuroscience, IN-CNR, Milan, Italy
| | | | | | - Michela Matteoli
- Institute of Neuroscience, IN-CNR, Milan, Italy
- Humanitas Clinical and Research Center – IRCCS, Rozzano, Milan, Italy
| | - Elisabetta Menna
- Institute of Neuroscience, IN-CNR, Milan, Italy
- Humanitas Clinical and Research Center – IRCCS, Rozzano, Milan, Italy
| | - Flavia Antonucci
- Department of Medical Biotechnology and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy
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18
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Byiers BJ, Payen A, Feyma T, Panoskaltsis-Mortari A, Ehrhardt MJ, Symons FJ. Associations Among Diurnal Salivary Cortisol Patterns, Medication Use, and Behavioral Phenotype Features in a Community Sample of Rett Syndrome. Am J Intellect Dev Disabil 2020; 125:353-368. [PMID: 32936892 PMCID: PMC10699094 DOI: 10.1352/1944-7558-125.5.353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 02/10/2020] [Indexed: 06/11/2023]
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder resulting from mutations of the MECP2 gene. Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and abnormal stress responses have been observed in animal models of RTT, but little is known about HPA axis function among individuals with RTT. Diurnal salivary cortisol patterns from 30 females with RTT were examined in relation to mutation type, medication use, and features of the RTT behavioral phenotype. Cortisol patterns were significantly related to mutation severity, anticonvulsant medication status, and bruxism (tooth grinding). This study provides preliminary support for the hypothesis that RTT may be at risk for outcomes associated with aberrant HPA axis function, and that this risk may be mediated by mutation type.
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Affiliation(s)
| | - Ameante Payen
- Breanne J. Byiers and Ameante Payen, University of Minnesota
| | - Timothy Feyma
- Timothy Feyma, Gillette Children's Specialty Healthcare, St. Paul, Minnesota
| | | | - Michael J Ehrhardt
- Angela Panoskaltsis-Mortari, Michael J. Ehrhardt, and Frank J. Symons, University of Minnesota
| | - Frank J Symons
- Angela Panoskaltsis-Mortari, Michael J. Ehrhardt, and Frank J. Symons, University of Minnesota
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19
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Xiang Y, Tanaka Y, Patterson B, Hwang SM, Hysolli E, Cakir B, Kim KY, Wang W, Kang YJ, Clement EM, Zhong M, Lee SH, Cho YS, Patra P, Sullivan GJ, Weissman SM, Park IH. Dysregulation of BRD4 Function Underlies the Functional Abnormalities of MeCP2 Mutant Neurons. Mol Cell 2020; 79:84-98.e9. [PMID: 32526163 DOI: 10.1016/j.molcel.2020.05.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 03/04/2020] [Accepted: 05/12/2020] [Indexed: 12/22/2022]
Abstract
Rett syndrome (RTT), mainly caused by mutations in methyl-CpG binding protein 2 (MeCP2), is one of the most prevalent intellectual disorders without effective therapies. Here, we used 2D and 3D human brain cultures to investigate MeCP2 function. We found that MeCP2 mutations cause severe abnormalities in human interneurons (INs). Surprisingly, treatment with a BET inhibitor, JQ1, rescued the molecular and functional phenotypes of MeCP2 mutant INs. We uncovered that abnormal increases in chromatin binding of BRD4 and enhancer-promoter interactions underlie the abnormal transcription in MeCP2 mutant INs, which were recovered to normal levels by JQ1. We revealed cell-type-specific transcriptome impairment in MeCP2 mutant region-specific human brain organoids that were rescued by JQ1. Finally, JQ1 ameliorated RTT-like phenotypes in mice. These data demonstrate that BRD4 dysregulation is a critical driver for RTT etiology and suggest that targeting BRD4 could be a potential therapeutic opportunity for RTT.
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Affiliation(s)
- Yangfei Xiang
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Yoshiaki Tanaka
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Benjamin Patterson
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Sung-Min Hwang
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Eriona Hysolli
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Bilal Cakir
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Kun-Yong Kim
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Wanshan Wang
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Young-Jin Kang
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Ethan M Clement
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Mei Zhong
- Department of Cell Biology, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Sang-Hun Lee
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Yee Sook Cho
- Regenerative Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, Republic of Korea
| | - Prabir Patra
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA; Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT 06604, USA
| | - Gareth J Sullivan
- Department of Molecular Medicine, Hybrid Technology Hub - Centre of Excellence, Institute of Basic Medical Sciences, Oslo University Hospital and University of Oslo, Oslo 0424, Norway; Department of Pediatric Research, Oslo University Hospital Rikshospitalet, Oslo 0372, Norway
| | - Sherman M Weissman
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - In-Hyun Park
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA.
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20
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Abstract
Dysfunctions in GABAergic inhibitory neural transmission occur in neuronal injuries and neurological disorders. The potassium-chloride cotransporter 2 (KCC2, SLC12A5) is a key modulator of inhibitory GABAergic inputs in healthy adult neurons, as its chloride (Cl-) extruding activity underlies the hyperpolarizing reversal potential for GABAA receptor Cl- currents (EGABA). Manipulation of KCC2 levels or activity improve symptoms associated with epilepsy and neuropathy. Recent works have now indicated that pharmacological enhancement of KCC2 function could reactivate dormant relay circuits in an injured mouse's spinal cord, leading to functional recovery and the attenuation of neuronal abnormality and disease phenotype associated with a mouse model of Rett syndrome (RTT). KCC2 interacts with Huntingtin and is downregulated in Huntington's disease (HD), which contributed to GABAergic excitation and memory deficits in the R6/2 mouse HD model. Here, these recent advances are highlighted, which attest to KCC2's growing potential as a therapeutic target for neuropathological conditions resulting from dysfunctional inhibitory input.
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Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore; ; Tel.: +65-6516-1040
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore 119077, Singapore
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21
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Kaufmann WE, Sprouse J, Rebowe N, Hanania T, Klamer D, Missling CU. ANAVEX®2-73 (blarcamesine), a Sigma-1 receptor agonist, ameliorates neurologic impairments in a mouse model of Rett syndrome. Pharmacol Biochem Behav 2019; 187:172796. [PMID: 31704481 DOI: 10.1016/j.pbb.2019.172796] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/26/2019] [Accepted: 10/04/2019] [Indexed: 11/23/2022]
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder that is associated in most cases with mutations in the transcriptional regulator MECP2. At present, there are no effective treatments for the disorder. Despite recent advances in RTT genetics and neurobiology, most drug development programs have focused on compounds targeting the IGF-1 pathway and no pivotal trial has been completed as yet. Thus, testing novel drugs that can ameliorate RTT's clinical manifestations is a high priority. ANAVEX2-73 (blarcamesine) is a Sigma-1 receptor agonist and muscarinic receptor modulator with a strong safety record and preliminary evidence of efficacy in patients with Alzheimer's disease. Its role in calcium homeostasis and mitochondrial function, cellular functions that underlie pathological processes and compensatory mechanisms in RTT, makes blarcamesine an intriguing drug candidate for this disorder. Mice deficient in MeCP2 have a range of physiological and neurological abnormalities that mimic the human syndrome. We tested blarcamesine in female heterozygous mice carrying one null allele of Mecp2 (HET) using a two-tier approach, with age-appropriate tests. Administration of the drug to younger and older adult mice resulted in improvement in multiple motor, sensory, and autonomic phenotypes of relevance to RTT. The latter included motor coordination and balance, acoustic and visual responses, hindlimb clasping, and apnea in expiration. In line with previous animal and human studies, blarcamesine also showed a good safety profile in this mouse model of RTT. Clinical studies in RTT with blarcamesine are ongoing.
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Affiliation(s)
- Walter E Kaufmann
- Anavex Life Sciences Corp., 51 West 52nd Street, 7th floor, New York, NY 10019, USA; Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Atlanta, GA 30322.
| | - Jeffrey Sprouse
- Anavex Life Sciences Corp., 51 West 52nd Street, 7th floor, New York, NY 10019, USA
| | - Nell Rebowe
- Anavex Life Sciences Corp., 51 West 52nd Street, 7th floor, New York, NY 10019, USA
| | - Taleen Hanania
- PsychoGenics Inc., 215 College Road, Paramus, NJ 07652, USA
| | - Daniel Klamer
- Anavex Life Sciences Corp., 51 West 52nd Street, 7th floor, New York, NY 10019, USA
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22
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Wiedemann A, Renard E, Hernandez M, Dousset B, Brezin F, Lambert L, Weryha G, Feillet F. Annual Injection of Zoledronic Acid Improves Bone Status in Children with Cerebral Palsy and Rett Syndrome. Calcif Tissue Int 2019; 104:355-363. [PMID: 30554334 DOI: 10.1007/s00223-018-0505-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 12/07/2018] [Indexed: 12/27/2022]
Abstract
Osteoporosis is a common complication of cerebral palsy and Rett's syndrome. It is responsible for multiple fractures, bone pain, and impaired quality of life. In case of Rett's syndrome, a specific dysfunction of osteoblasts causes bone fragility. We observed the effects of annual zoledronic acid (ZA) infusion in a cohort of children with cerebral palsy and Rett's syndrome. 27 children under 18 years (19 with cerebral palsy and 8 girls with Rett syndrome confirmed by MCEP2 mutation) were treated with an annual injection of 0.1 mg/kg (max 4 mg) of ZA. Calcium and vitamin D were combined in all patients from the first injection of ZA. Dental examination was performed before treatment. Data were analyzed retrospectively. Bone mineral density was measured at diagnosis and yearly thereafter. Bone mass density (BMD) is decreased in patient with cerebral palsy and RS. One year after injection of ZA, we observe an increase of Lumbar spine BMD from - 2.99 to - 2.14 SD (p < 0.0001) and femoral BMD from - 4.26 to - 3.32 SD (p < 0.001) In the subgroup of patient with Rett syndrome, we also observe an increase from - 3.27 to 2.50 SD (p = 0.018) of Lumbar spine BMD. No fractures have been observed in our cohort since the first infusion. Side effects (flu-like syndrome and hypocalcemia) were more common in younger patients and after the first infusion. No serious complications were noticed. This study confirms the efficacy and the safety of an annual injection of ZA to improve bone status in children with cerebral palsy and Rett syndrome. No severe adverse effects were observed.
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Affiliation(s)
- Arnaud Wiedemann
- Centre de référence des erreurs innées du métabolisme, Hôpital d'Enfants, CHRU Nancy, Nancy, France.
- Réanimation pédiatrique spécialisée, Hôpital d'enfants, CHRU Nancy, Nancy, France.
- Faculté de médecine, INSERM U-1256, Vandoeuvre les Nancy, France.
| | - Emeline Renard
- Service de Médecine Infantile, Hôpital d'enfants, CHRU Nancy, Nancy, France
- Faculté de médecine, INSERM U-1256, Vandoeuvre les Nancy, France
| | | | | | - François Brezin
- Service de Médecine Infantile, Hôpital d'enfants, CHRU Nancy, Nancy, France
| | | | | | - François Feillet
- Centre de référence des erreurs innées du métabolisme, Hôpital d'Enfants, CHRU Nancy, Nancy, France
- Service de Médecine Infantile, Hôpital d'enfants, CHRU Nancy, Nancy, France
- Faculté de médecine, INSERM U-1256, Vandoeuvre les Nancy, France
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23
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Gogliotti RG, Fisher NM, Stansley BJ, Jones CK, Lindsley CW, Conn PJ, Niswender CM. Total RNA Sequencing of Rett Syndrome Autopsy Samples Identifies the M 4 Muscarinic Receptor as a Novel Therapeutic Target. J Pharmacol Exp Ther 2018; 365:291-300. [PMID: 29523700 PMCID: PMC5878667 DOI: 10.1124/jpet.117.246991] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 03/08/2018] [Indexed: 02/04/2023] Open
Abstract
Mutations in the MeCP2 gene are responsible for the neurodevelopmental disorder Rett syndrome (RTT). MeCP2 is a DNA-binding protein whose abundance and ability to complex with histone deacetylase 3 is linked to the regulation of chromatin structure. Consequently, loss-of-function mutations in MeCP2 are predicted to have broad effects on gene expression. However, to date, studies in mouse models of RTT have identified a limited number of gene or pathway-level disruptions, and even fewer genes have been identified that could be considered amenable to classic drug discovery approaches. Here, we performed RNA sequencing (RNA-seq) on nine motor cortex and six cerebellar autopsy samples from RTT patients and controls. This approach identified 1887 significantly affected genes in the motor cortex and 2110 genes in the cerebellum, with a global trend toward increased expression. Pathway-level analysis identified enrichment in genes associated with mitogen-activated protein kinase signaling, long-term potentiation, and axon guidance. A survey of our RNA-seq results also identified a significant decrease in expression of the CHRM4 gene, which encodes a receptor [muscarinic acetylcholine receptor 4 (M4)] that is the subject of multiple large drug discovery efforts for schizophrenia and Alzheimer's disease. We confirmed that CHRM4 expression was decreased in RTT patients, and, excitingly, we demonstrated that M4 potentiation normalizes social and cognitive phenotypes in Mecp2+/- mice. This work provides an experimental paradigm in which translationally relevant targets can be identified using transcriptomics in RTT autopsy samples, back-modeled in Mecp2+/- mice, and assessed for preclinical efficacy using existing pharmacological tool compounds.
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Affiliation(s)
- Rocco G Gogliotti
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
| | - Nicole M Fisher
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
| | - Branden J Stansley
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
| | - Carrie K Jones
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
| | - Craig W Lindsley
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
| | - P Jeffrey Conn
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
| | - Colleen M Niswender
- Departments of Pharmacology (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.) and Chemistry (C.W.L.), and Vanderbilt Center for Neuroscience Drug Discovery (R.G.G., N.M.F., B.J.S., C.K.J., C.W.L., P.J.C., C.M.N.), Vanderbilt University, Nashville, Tennessee; and Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee (P.J.C., C.M.N.)
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24
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Abstract
Rett syndrome (RTT) is a neurological disorder caused by mutations in the X-linked gene methyl-CpG-binding protein 2 (MECP2), a ubiquitously expressed transcriptional regulator. Despite remarkable scientific progress since its discovery, the mechanism by which MECP2 mutations cause RTT symptoms is largely unknown. Consequently, treatment options for patients are currently limited and centred on symptom relief. Thought to be an entirely neurological disorder, RTT research has focused on the role of MECP2 in the central nervous system. However, the variety of phenotypes identified in Mecp2 mutant mouse models and RTT patients implicate important roles for MeCP2 in peripheral systems. Here, we review the history of RTT, highlighting breakthroughs in the field that have led us to present day. We explore the current evidence supporting metabolic dysfunction as a component of RTT, presenting recent studies that have revealed perturbed lipid metabolism in the brain and peripheral tissues of mouse models and patients. Such findings may have an impact on the quality of life of RTT patients as both dietary and drug intervention can alter lipid metabolism. Ultimately, we conclude that a thorough knowledge of MeCP2's varied functional targets in the brain and body will be required to treat this complex syndrome.
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Affiliation(s)
- Stephanie M Kyle
- Genetics and Genome Biology Program, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada M5G 0A4
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Neeti Vashi
- Genetics and Genome Biology Program, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada M5G 0A4
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A1
| | - Monica J Justice
- Genetics and Genome Biology Program, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada M5G 0A4
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A1
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25
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Na ES, De Jesús-Cortés H, Martinez-Rivera A, Kabir ZD, Wang J, Ramesh V, Onder Y, Rajadhyaksha AM, Monteggia LM, Pieper AA. D-cycloserine improves synaptic transmission in an animal model of Rett syndrome. PLoS One 2017; 12:e0183026. [PMID: 28813484 PMCID: PMC5559075 DOI: 10.1371/journal.pone.0183026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 07/30/2017] [Indexed: 01/24/2023] Open
Abstract
Rett syndrome (RTT), a leading cause of intellectual disability in girls, is predominantly caused by mutations in the X-linked gene MECP2. Disruption of Mecp2 in mice recapitulates major features of RTT, including neurobehavioral abnormalities, which can be reversed by re-expression of normal Mecp2. Thus, there is reason to believe that RTT could be amenable to therapeutic intervention throughout the lifespan of patients after the onset of symptoms. A common feature underlying neuropsychiatric disorders, including RTT, is altered synaptic function in the brain. Here, we show that Mecp2tm1.1Jae/y mice display lower presynaptic function as assessed by paired pulse ratio, as well as decreased long term potentiation (LTP) at hippocampal Schaffer–collateral-CA1 synapses. Treatment of Mecp2tm1.1Jae/y mice with D-cycloserine (DCS), an FDA-approved analog of the amino acid D-alanine with antibiotic and glycinergic activity, corrected the presynaptic but not LTP deficit without affecting deficient hippocampal BDNF levels. DCS treatment did, however, partially restore lower BDNF levels in the brain stem and striatum. Thus, treatment with DCS may mitigate the severity of some of the neurobehavioral symptoms experienced by patients with Rett syndrome.
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Affiliation(s)
- Elisa S. Na
- Department of Psychology & Philosophy, Texas Woman’s University, Denton, TX, United States of America
| | - Héctor De Jesús-Cortés
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Arlene Martinez-Rivera
- Division of Pediatric Neurology, Department of Pediatrics, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
- Weill Cornell Autism Research Program, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
| | - Zeeba D. Kabir
- Division of Pediatric Neurology, Department of Pediatrics, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
- Weill Cornell Autism Research Program, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
| | - Jieqi Wang
- Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, IA, United States of America
| | - Vijayashree Ramesh
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX, United States of America
| | - Yasemin Onder
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX, United States of America
| | - Anjali M. Rajadhyaksha
- Division of Pediatric Neurology, Department of Pediatrics, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
- Weill Cornell Autism Research Program, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
- * E-mail: (AMR); (LMM); (AAP)
| | - Lisa M. Monteggia
- Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX, United States of America
- * E-mail: (AMR); (LMM); (AAP)
| | - Andrew A. Pieper
- Weill Cornell Autism Research Program, Weill Cornell Medicine, Cornell University, New York, NY, United States of America
- Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, IA, United States of America
- Department of Neurology, University of Iowa Carver College of Medicine, Iowa City, IA, United States of America
- Department of Free Radical and Radiation Biology, University of Iowa Carver College of Medicine, Iowa City, IA, United States of America
- Department of Veterans Affairs, University of Iowa Carver College of Medicine, Iowa City, IA, United States of America
- Pappajohn Biomedical Institute, University of Iowa Carver College of Medicine, Iowa City, IA, United States of America
- * E-mail: (AMR); (LMM); (AAP)
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26
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Shapiro JR, Boskey AL, Doty SB, Lukashova L, Blue ME. Zoledronic acid improves bone histomorphometry in a murine model of Rett syndrome. Bone 2017; 99:1-7. [PMID: 28323142 DOI: 10.1016/j.bone.2017.03.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 02/06/2017] [Accepted: 03/15/2017] [Indexed: 12/01/2022]
Abstract
Rett syndrome (RTT) is a neurodevelopmental disorder predominately affecting young females, caused by deficiency of the global transcriptional protein methyl CpG binding protein 2 (MeCP2). Osteoblasts express MeCP2 and girls with RTT experience early onset osteoporosis, decreased bone mass and an increased fracture risk. There is no defined treatment for osteoporosis associated with RTT. The present study evaluated the effects of zoledronic acid (ZA), a third generation nitrogen-containing bisphosphonate with primarily anti-osteoclastic activity, in a mouse model of MeCP2 deficiency. Mice received weekly injections of 20μg/kg ZA for six weeks. Due to the shortened lifespan of hemizygous male (Mecp2-null) mice, treatment began at 3weeks of age for this group and corresponding wildtype (WT) male mice. Treatment for heterozygous (HET) and WT female mice began at 8weeks of age. Micro-computed tomography (micro-CT) and dynamic analyses of bone turnover were performed. ZA treatment led to significant increases in bone volume fraction, number, connectivity density and apparent density of trabecular bone in all genotypes of mice. In contrast, cortical bone generally was unaffected by ZA injections. Parameters of bone turnover, including mineral apposition rate, labeled bone surface and bone formation rate decreased after treatment with ZA. Mecp2-null mice had reduced labeled bone surface and bone formation rate compared to WT male mice. The results indicate that ZA treatment significantly improved trabecular bone mass in a murine model of RTT with little effect on cortical bone.
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Affiliation(s)
- Jay R Shapiro
- Hugo W. Moser Research Institute at Kennedy Krieger, Inc., 707 North Broadway, Baltimore, MD 21205, USA
| | - Adele L Boskey
- Hospital for Special Surgery, Mineralized Tissue Laboratory, 535 E 70th Street, New York, NY 10021, USA.
| | - Stephen B Doty
- Hospital for Special Surgery, Mineralized Tissue Laboratory, 535 E 70th Street, New York, NY 10021, USA.
| | - Lyudmila Lukashova
- Hospital for Special Surgery, Mineralized Tissue Laboratory, 535 E 70th Street, New York, NY 10021, USA.
| | - Mary E Blue
- Hugo W. Moser Research Institute at Kennedy Krieger, Inc., 707 North Broadway, Baltimore, MD 21205, USA.
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27
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Zanchetta MB, Scioscia MF, Zanchetta JR. Bone microarchitecture in Rett syndrome and treatment with teriparatide: a case report. Osteoporos Int 2016; 27:2873-2877. [PMID: 27068223 DOI: 10.1007/s00198-016-3586-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 03/30/2016] [Indexed: 01/07/2023]
Abstract
We present the case of a 28-year-old female Rett syndrome patient with low bone mass and a recent fracture who was successfully treated with teriparatide. Bone mineral density and microarchitecture substantially improved after treatment. Rett syndrome (RTT), an X-linked progressive neuro-developmental disorder caused by mutations in the methyl-CpG-binding 2 (MECP2) gene, has been consistently associated with low bone mass. Consequently, patients with RTT are at increased risk of skeletal fractures. Teriparatide is a bone-forming agent for the treatment of osteoporosis that has demonstrated its effectiveness in increasing bone strength and reducing the risk of fractures in postmenopausal women, but, recently, its positive action has also been reported in premenopausal women. We present the case of a 28-year-old female RTT patient with low bone mass and a recent fracture who was successfully treated with teriparatide. Both bone mass measured by DXA and microarchitecture assessed by high resolution peripheral computed tomography (HR pQCT) were substantially improved after treatment.
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Affiliation(s)
- M B Zanchetta
- IDIM, Instituto de Diagnóstico e Investigaciones Metabólicas, Cátedra de Osteología y Metabolismo Mineral, Facultad de Medicina, Universidad del Salvador, Libertad 836, 1st Floor, 1012, Buenos Aires, Argentina.
| | - M F Scioscia
- IDIM, Instituto de Diagnóstico e Investigaciones Metabólicas, Cátedra de Osteología y Metabolismo Mineral, Facultad de Medicina, Universidad del Salvador, Libertad 836, 1st Floor, 1012, Buenos Aires, Argentina
| | - J R Zanchetta
- IDIM, Instituto de Diagnóstico e Investigaciones Metabólicas, Cátedra de Osteología y Metabolismo Mineral, Facultad de Medicina, Universidad del Salvador, Libertad 836, 1st Floor, 1012, Buenos Aires, Argentina
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28
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Patrizi A, Picard N, Simon AJ, Gunner G, Centofante E, Andrews NA, Fagiolini M. Chronic Administration of the N-Methyl-D-Aspartate Receptor Antagonist Ketamine Improves Rett Syndrome Phenotype. Biol Psychiatry 2016; 79:755-764. [PMID: 26410354 PMCID: PMC7410367 DOI: 10.1016/j.biopsych.2015.08.018] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 08/13/2015] [Accepted: 08/13/2015] [Indexed: 12/26/2022]
Abstract
BACKGROUND Rett syndrome (RTT) is a neurological disorder caused by mutation of the X-linked MECP2 gene, which results in the progressive disruption of excitatory and inhibitory neuronal circuits. To date, there is no effective treatment available for the disorder. Studies conducted in RTT patients and murine models have shown altered expression of N-methyl-D-aspartate receptors (NMDARs). Genetic deletion of the NMDAR subunit, GluN2A, in mice lacking Mecp2 is sufficient to prevent RTT phenotypes, including regression of vision. METHODS We performed a systematic, randomized preclinical trial of chronic administration of low-dose (8 mg/kg, intraperitoneal) ketamine, an NMDAR antagonist, starting either early in development or at the onset of RTT phenotype in Mecp2-null mice. RESULTS Daily exposure to ketamine ameliorated RTT symptoms and extended the life span of treated Mecp2-null mice without adverse side effects. Furthermore, significant improvement was observed in cortical processing and connectivity, which were fully restored to a wild-type level, particularly when treatment was started at the onset of regression. CONCLUSIONS Our findings provide strong evidence that targeting NMDA receptors can be a safe and effective treatment for RTT.
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Affiliation(s)
- Annarita Patrizi
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Nathalie Picard
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Alex Joseph Simon
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Georgia Gunner
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Eleonora Centofante
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Nick Arthur Andrews
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Michela Fagiolini
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
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29
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Sykut-Cegielska J. Advances in treatment of Rett syndrome. Dev Period Med 2015; 19:482-483. [PMID: 26982757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Jolanta Sykut-Cegielska
- Screening Department Institute of Mother and Child, ul. Kasprzaka 17A, 01-211 Warsaw, tel. (+48 22) 32-77-375, fax: (+48 22) 32-77-375, e-mail:
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30
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Abstract
Rett syndrome (RTT) is an X-linked neurodevelopmental disorder that is characterized by successive loss of acquired cognitive, social, and motor skills and development of autistic behavior. RTT affects approximately 1 in 10,000 live female births and is the second most common cause of severe mental retardation in females, after Down syndrome. Currently, there is no cure or effective therapy for RTT. Approved treatment regimens are presently limited to supportive management of specific physical and mental disabilities. In this issue, Krishnan and colleagues reveal that the protein tyrosine phosphatase PTP1B is upregulated in patients with RTT and in murine models and provide strong evidence that targeting PTP1B has potential as a viable therapeutic strategy for the treatment of RTT.
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Krishnan N, Krishnan K, Connors CR, Choy MS, Page R, Peti W, Van Aelst L, Shea SD, Tonks NK. PTP1B inhibition suggests a therapeutic strategy for Rett syndrome. J Clin Invest 2015. [PMID: 26214522 DOI: 10.1172/jci80323] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The X-linked neurological disorder Rett syndrome (RTT) presents with autistic features and is caused primarily by mutations in a transcriptional regulator, methyl CpG-binding protein 2 (MECP2). Current treatment options for RTT are limited to alleviating some neurological symptoms; hence, more effective therapeutic strategies are needed. We identified the protein tyrosine phosphatase PTP1B as a therapeutic candidate for treatment of RTT. We demonstrated that the PTPN1 gene, which encodes PTP1B, was a target of MECP2 and that disruption of MECP2 function was associated with increased levels of PTP1B in RTT models. Pharmacological inhibition of PTP1B ameliorated the effects of MECP2 disruption in mouse models of RTT, including improved survival in young male (Mecp2-/y) mice and improved behavior in female heterozygous (Mecp2-/+) mice. We demonstrated that PTP1B was a negative regulator of tyrosine phosphorylation of the tyrosine kinase TRKB, the receptor for brain-derived neurotrophic factor (BDNF). Therefore, the elevated PTP1B that accompanies disruption of MECP2 function in RTT represents a barrier to BDNF signaling. Inhibition of PTP1B led to increased tyrosine phosphorylation of TRKB in the brain, which would augment BDNF signaling. This study presents PTP1B as a mechanism-based therapeutic target for RTT, validating a unique strategy for treating the disease by modifying signal transduction pathways with small-molecule drugs.
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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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Pintaudi M, Calevo MG, Vignoli A, Baglietto MG, Hayek Y, Traverso M, Giacomini T, Giordano L, Renieri A, Russo S, Canevini M, Veneselli E. Antiepileptic drugs in Rett Syndrome. Eur J Paediatr Neurol 2015; 19:446-52. [PMID: 25814391 DOI: 10.1016/j.ejpn.2015.02.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/03/2015] [Accepted: 02/21/2015] [Indexed: 11/19/2022]
Abstract
PURPOSE We investigated drugs most often used to treat epilepsy in Rett Syndrome and their efficacy in a large cohort of Italian patients. METHODS This is a multi-centre retrospective study. Data of 165 Rett subjects were collected from the patients' files, and hospital charts. The efficacy of antiepileptic drugs (AEDs) was classified as follows: not effective; decrease in seizure frequency ≥50% for at least 6 months; seizure-free for at least 2 years. Phenotypic and genetic categorization of patients was performed and it was considered in AEDs efficacy evaluation. RESULTS There were 130 epileptic patients.Sodium valproate (VPA) was the most commonly administered AED (44.3%) at seizure onset, followed by Carbamazepine (CBZ) (25.4%) and Phenobarbital (PB) (13%). Monotherapy was the first treatment option in most patients. VPA and CBZ proved to be equally effective in Rett patients who presented seizures within the typical age range (4-5 years), while Lamotrigine (LTG) was effective for patients in whom epilepsy started later. Overall, the frequency of side effects was low and the most often observed ones were restlessness and somnolence. CONCLUSION Our study suggests that LTG, VPA and CBZ can be used as drugs of first choice in Rett Syndrome. The association of four drugs should be avoided since it did not result in any significant clinical improvement.
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Affiliation(s)
| | - Maria Grazia Calevo
- Epidemiology and Biostatistics Unit, Istituto Giannina Gaslini, Genoa, Italy
| | - Aglaia Vignoli
- Department of Health Science, Epilepsy Centre, St. Paolo Hospital, University of Milan, Italy
| | - Maria Giuseppina Baglietto
- University of Genoa, DINOGMI, Italy; Department of Child Neuropsychiatry, Epilepsy Centre, Giannina Gaslini Institute, Italy
| | - Yussef Hayek
- Pediatric Neuropsychiatric Unit, University Hospital, Policlinico Le Scotte, Siena, Italy
| | - Maria Traverso
- University of Genoa, DINOGMI, Italy; Department of Child Neuropsychiatry, Epilepsy Centre, Giannina Gaslini Institute, Italy
| | - Thea Giacomini
- University of Genoa, DINOGMI, Italy; Department of Child Neuropsychiatry, Epilepsy Centre, Giannina Gaslini Institute, Italy
| | - Lucio Giordano
- Pediatric Neuropsychiatric Division, City Hospital of Brescia, Brescia, Italy
| | - Alessandra Renieri
- Medical Genetics, University of Siena, Siena, Italy; Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Silvia Russo
- Department of Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy
| | - MariaPaola Canevini
- Department of Health Science, Epilepsy Centre, St. Paolo Hospital, University of Milan, Italy
| | - Edvige Veneselli
- University of Genoa, DINOGMI, Italy; Department of Child Neuropsychiatry, Epilepsy Centre, Giannina Gaslini Institute, Italy
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Hjalmgrim H, Hansen LK, Ousager LB, Møller RS. [Early-onset epileptic encephalopathy caused by CDKL5 mutation]. Ugeskr Laeger 2014; 176:V01130031. [PMID: 25497626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Two girls suffering from early-onset epileptic encephalopathy are described. Both girls had changes involving the gene CDKL5. They both had seizures in the first weeks of life and normal EEG interictally. Both developed infantile spasms and severe developmental defect. The epilepsy was difficult to treat.
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De Filippis B, Nativio P, Fabbri A, Ricceri L, Adriani W, Lacivita E, Leopoldo M, Passarelli F, Fuso A, Laviola G. Pharmacological stimulation of the brain serotonin receptor 7 as a novel therapeutic approach for Rett syndrome. Neuropsychopharmacology 2014; 39:2506-18. [PMID: 24809912 PMCID: PMC4207333 DOI: 10.1038/npp.2014.105] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 04/29/2014] [Accepted: 04/30/2014] [Indexed: 01/01/2023]
Abstract
Rett syndrome (RTT) is a rare neurodevelopmental disorder, characterized by severe behavioral and physiological symptoms. Mutations in the methyl CpG-binding protein 2 gene (MECP2) cause >95% of classic cases, and currently there is no cure for this devastating disorder. The serotonin receptor 7 (5-HT7R) is linked to neuro-physiological regulation of circadian rhythm, mood, cognition, and synaptic plasticity. We presently report that 5-HT7R density is consistently reduced in cortical and hippocampal brain areas of symptomatic MeCP2-308 male mice, a RTT model. Systemic repeated treatment with LP-211 (0.25 mg/kg once/day for 7 days), a brain-penetrant selective 5-HT7R agonist, was able to rescue RTT-related defective performance: anxiety-related profiles in a Light/Dark test, motor abilities in a Dowel test, the exploratory behavior in the Marble Burying test, as well as memory in the Novelty Preference task. In the brain of RTT mice, LP-211 also reversed the abnormal activation of PAK and cofilin (key regulators of actin cytoskeleton dynamics) and of the ribosomal protein (rp) S6, whose reduced activation in MECP2 mutant neurons by mTOR is responsible for the altered protein translational control. Present findings indicate that pharmacological targeting of 5-HT7R improves specific behavioral and molecular manifestations of RTT, thus representing a first step toward the validation of an innovative systemic treatment. Beyond RTT, the latter might be extended to other disorders associated with intellectual disability.
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Affiliation(s)
- Bianca De Filippis
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Paola Nativio
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Alessia Fabbri
- Department of Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Rome, Italy
| | - Laura Ricceri
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Walter Adriani
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy
| | - Enza Lacivita
- Department of Pharmacy, University of Bari ‘A Moro', Bari, Italy
| | | | | | - Andrea Fuso
- Department of Psychology, Section of Neuroscience, Sapienza University of Rome, Rome, Italy
- European Center for Brain Research (CERC)/IRCCS Santa Lucia Foundation, Rome, Italy
| | - Giovanni Laviola
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy
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Hagebeuk EEO, Duran M, Abeling NGGM, Vyth A, Poll-The BT. S-adenosylmethionine and S-adenosylhomocysteine in plasma and cerebrospinal fluid in Rett syndrome and the effect of folinic acid supplementation. J Inherit Metab Dis 2013; 36:967-72. [PMID: 23392989 DOI: 10.1007/s10545-013-9590-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 12/22/2012] [Accepted: 01/17/2013] [Indexed: 10/27/2022]
Abstract
Rett syndrome is a neurodevelopmental disorder characterized by cognitive and locomotor regression and stereotypic hand movements. The disorder is caused by mutations in the X chromosomal MECP2 a gene encoding methyl CpG-binding protein. It has been associated with disturbances of cerebral folate homeostasis, as well as with speculations on a compromised DNA-methylation. Folinic acid is the stable form of folate. Its derived intermediate 5-MTHF supports the conversion of homocysteine to methionine, the precursor of S-adenosylmethionine (SAM). This in turn donates its methyl group to various acceptors, including DNA, thereby being converted to S-adenosylhomocysteine (SAH). The SAM/SAH ratio reflects the methylation potential. The goal of our study was to influence DNA methylation processes and ameliorate the clinical symptoms in Rett syndrome. Therefore we examined the hypothesis that folinic acid supplementation, besides increasing cerebrospinal fluid (CSF) 5-MTHF (p = 0.003), influences SAM and SAH and their ratio. In our randomized, double-blind crossover study on folinic acid supplementation, ten female Rett patients received both folinic acid and placebo for 1 year each. It was shown that both SAM and SAH levels in the CSF remained unchanged following folinic acid administration (p = 0.202 and p = 0.097, respectively) in spite of a rise of plasma SAM and SAH (p = 0.007; p = 0.009). There was no significant change in the SAM/SAH ratio either in plasma or CSF. The apparent inability of Rett patients to upregulate SAM and SAH levels in the CSF may contribute to the biochemical anomalies of the Rett syndrome. Our studies warrant further attempts to promote DNA methylation in the true region of interest, i.e. the brain.
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Affiliation(s)
- Eveline E O Hagebeuk
- Department of Pediatric Neurology, Academic Medical Center, PO Box 22660, 1000 AZ, Amsterdam, The Netherlands,
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37
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Panighini A, Duranti E, Santini F, Maffei M, Pizzorusso T, Funel N, Taddei S, Bernardini N, Ippolito C, Virdis A, Costa M. Vascular dysfunction in a mouse model of Rett syndrome and effects of curcumin treatment. PLoS One 2013; 8:e64863. [PMID: 23705018 PMCID: PMC3660336 DOI: 10.1371/journal.pone.0064863] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 04/22/2013] [Indexed: 02/07/2023] Open
Abstract
Mutations in the coding sequence of the X-linked gene MeCP2 (Methyl CpG–binding protein) are present in around 80% of patients with Rett Syndrome, a common cause of intellectual disability in female and to date without any effective pharmacological treatment. A relevant, and so far unexplored feature of RTT patients, is a marked reduction in peripheral circulation. To investigate the relationship between loss of MeCP2 and this clinical aspect, we used the MeCP2 null mouse model B6.129SF1-MeCP2tm1Jae for functional and pharmacological studies. Functional experiments were performed on isolated resistance mesenteric vessels, mounted on a pressurized myograph. Vessels from female MeCP2+/− mice show a reduced endothelium-dependent relaxation, due to a reduced Nitric Oxide (NO) availability secondary to an increased Reactive Oxygen Species (ROS) generation. Such functional aspects are associated with an intravascular increase in superoxide anion production, and a decreased vascular eNOS expression. These alterations are reversed by curcumin administration (5% (w/w) dietary curcumin for 21 days), which restores endothelial NO availability, decreases intravascular ROS production and normalizes vascular eNOS gene expression. In conclusion our findings highlight alterations in the vascular/endothelial system in the absence of a correct function of MeCP2, and uncover related cellular/molecular mechanisms that are rescued by an anti-oxidant treatment.
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MESH Headings
- Animals
- Blood Vessels/drug effects
- Blood Vessels/physiopathology
- Curcumin/administration & dosage
- Curcumin/pharmacology
- Curcumin/therapeutic use
- Disease Models, Animal
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Endothelium, Vascular/pathology
- Endothelium, Vascular/physiopathology
- Female
- Gene Expression Regulation, Enzymologic/drug effects
- Immunohistochemistry
- Malondialdehyde/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Nitric Oxide Synthase Type III/genetics
- Nitric Oxide Synthase Type III/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rett Syndrome/complications
- Rett Syndrome/drug therapy
- Rett Syndrome/physiopathology
- Superoxides/metabolism
- Time Factors
- Vascular Diseases/complications
- Vascular Diseases/drug therapy
- Vascular Diseases/physiopathology
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Affiliation(s)
- Anna Panighini
- Institute of Neuroscience, Italian National Research Council (CNR), Pisa, Italy
| | - Emiliano Duranti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Ferruccio Santini
- Department of Endocrinology and Kidney; University-Hospital of Pisa, Pisa, Italy
| | - Margherita Maffei
- Department of Endocrinology and Kidney; University-Hospital of Pisa, Pisa, Italy
- Dulbecco Telethon Institute, Rome, Italy
- Institute of Food Science, CNR, Avellino, Italy
| | - Tommaso Pizzorusso
- Institute of Neuroscience, Italian National Research Council (CNR), Pisa, Italy
- Institute of Psychology, University of Florence, Florence, Italy
| | - Niccola Funel
- Department of Surgery, University of Pisa, Pisa, Italy
| | - Stefano Taddei
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Nunzia Bernardini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Chiara Ippolito
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Agostino Virdis
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
- * E-mail: (AV); (MC)
| | - Mario Costa
- Institute of Neuroscience, Italian National Research Council (CNR), Pisa, Italy
- Scuola Normale Superiore, Pisa, Italy
- * E-mail: (AV); (MC)
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Schaevitz LR, Nicolai R, Lopez CM, D'Iddio S, Iannoni E, Berger-Sweeney JE. Acetyl-L-carnitine improves behavior and dendritic morphology in a mouse model of Rett syndrome. PLoS One 2012; 7:e51586. [PMID: 23227269 PMCID: PMC3515484 DOI: 10.1371/journal.pone.0051586] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 11/05/2012] [Indexed: 11/18/2022] Open
Abstract
Rett syndrome (RTT) is a devastating neurodevelopmental disorder affecting 1 in 10,000 girls. Approximately 90% of cases are caused by spontaneous mutations in the X-linked gene encoding methyl-CpG-binding protein 2 (MeCP2). Girls with RTT suffer from severe motor, respiratory, cognitive and social abnormalities attributed to early deficits in synaptic connectivity which manifest in the adult as a myriad of physiological and anatomical abnormalities including, but not limited to, dimished dendritic complexity. Supplementation with acetyl-L-carnitine (ALC), an acetyl group donor, ameliorates motor and cognitive deficits in other disease models through a variety of mechanisms including altering patterns of histone acetylation resulting in changes in gene expression, and stimulating biosynthetic pathways such as acetylcholine. We hypothesized ALC treatment during critical periods in cortical development would promote normal synaptic maturation, and continuing treatment would improve behavioral deficits in the Mecp2(1lox) mouse model of RTT. In this study, wildtype and Mecp2(1lox) mutant mice received daily injections of ALC from birth until death (postnatal day 47). General health, motor, respiratory, and cognitive functions were assessed at several time points during symptom progression. ALC improved weight gain, grip strength, activity levels, prevented metabolic abnormalities and modestly improved cognitive function in Mecp2 null mice early in the course of treatment, but did not significantly improve motor or cognitive functions assessed later in life. ALC treatment from birth was associated with an almost complete rescue of hippocampal dendritic morphology abnormalities with no discernable side effects in the mutant mice. Therefore, ALC appears to be a promising therapeutic approach to treating early RTT symptoms and may be useful in combination with other therapies.
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Affiliation(s)
- Laura R Schaevitz
- Department of Biology, Wellesley College, Wellesley, Massachusetts, United States of America.
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39
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Sasaki K. [Effect of tracheostomy with imipramine on apneusis attacks in a girl with Rett syndrome]. No To Hattatsu 2012; 44:492-495. [PMID: 23240533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A girl with Rett syndrome was suffered from severe apneusis attacks, resulting in cardiopulmonary arrest, which required resuscitation. Her apneusis attacks did not respond at all to diazepam, magnesium citrare or tricyclic antidepressants but ceased by tracheostomy with oral imipramine. The breathing abnormality appeared to involve difficulty in terminating inspiration. This supports the idea that a lack of serotonin may cause her apneusis attacks.
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Affiliation(s)
- Kaori Sasaki
- Department of Pediatrics, Kakogawa East City Hospital, Kakogawa, Hyogo.
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40
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De Filippis B, Fabbri A, Simone D, Canese R, Ricceri L, Malchiodi-Albedi F, Laviola G, Fiorentini C. Modulation of RhoGTPases improves the behavioral phenotype and reverses astrocytic deficits in a mouse model of Rett syndrome. Neuropsychopharmacology 2012; 37:1152-63. [PMID: 22157810 PMCID: PMC3306877 DOI: 10.1038/npp.2011.301] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 10/28/2011] [Accepted: 10/28/2011] [Indexed: 11/09/2022]
Abstract
RhoGTPases are crucial molecules in neuronal plasticity and cognition, as confirmed by their role in non-syndromic mental retardation. Activation of brain RhoGTPases by the bacterial cytotoxic necrotizing factor 1 (CNF1) reshapes the actin cytoskeleton and enhances neurotransmission and synaptic plasticity in mouse brains. We evaluated the effects of a single CNF1 intracerebroventricular inoculation in a mouse model of Rett syndrome (RTT), a rare neurodevelopmental disorder and a genetic cause of mental retardation, for which no effective therapy is available. Fully symptomatic MeCP2-308 male mice were evaluated in a battery of tests specifically tailored to detect RTT-related impairments. At the end of behavioral testing, brain sections were immunohistochemically characterized. Magnetic resonance imaging and spectroscopy (MRS) were also applied to assess morphological and metabolic brain changes. The CNF1 administration markedly improved the behavioral phenotype of MeCP2-308 mice. CNF1 also dramatically reversed the evident signs of atrophy in astrocytes of mutant mice and restored wt-like levels of this cell population. A partial rescue of the overexpression of IL-6 cytokine was also observed in RTT brains. CNF1-induced brain metabolic changes detected by MRS analysis involved markers of glial integrity and bioenergetics, and point to improved mitochondria functionality in CNF1-treated mice. These results clearly indicate that modulation of brain RhoGTPases by CNF1 may constitute a totally innovative therapeutic approach for RTT and, possibly, for other disorders associated with mental retardation.
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Affiliation(s)
- Bianca De Filippis
- Department Cell Biology and Neuroscience, Istituto Superiore di Sanità, Roma, Italy
| | - Alessia Fabbri
- Department Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Roma, Italy
| | - Daiana Simone
- Department Cell Biology and Neuroscience, Istituto Superiore di Sanità, Roma, Italy
| | - Rossella Canese
- Department Cell Biology and Neuroscience, Istituto Superiore di Sanità, Roma, Italy
| | - Laura Ricceri
- Department Cell Biology and Neuroscience, Istituto Superiore di Sanità, Roma, Italy
| | | | - Giovanni Laviola
- Department Cell Biology and Neuroscience, Istituto Superiore di Sanità, Roma, Italy
| | - Carla Fiorentini
- Department Therapeutic Research and Medicines Evaluation, Istituto Superiore di Sanità, Roma, Italy
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41
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Schmid DA, Yang T, Ogier M, Adams I, Mirakhur Y, Wang Q, Massa SM, Longo FM, Katz DM. A TrkB small molecule partial agonist rescues TrkB phosphorylation deficits and improves respiratory function in a mouse model of Rett syndrome. J Neurosci 2012; 32:1803-10. [PMID: 22302819 PMCID: PMC3710112 DOI: 10.1523/jneurosci.0865-11.2012] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 12/02/2011] [Accepted: 12/13/2011] [Indexed: 02/07/2023] Open
Abstract
Rett syndrome (RTT) results from loss-of-function mutations in the gene encoding the methyl-CpG-binding protein 2 (MeCP2) and is characterized by abnormal motor, respiratory and autonomic control, cognitive impairment, autistic-like behaviors and increased risk of seizures. RTT patients and Mecp2-null mice exhibit reduced expression of brain-derived neurotrophic factor (BDNF), which has been linked in mice to increased respiratory frequency, a hallmark of RTT. The present study was undertaken to test the hypotheses that BDNF deficits in Mecp2 mutants are associated with reduced activation of the BDNF receptor, TrkB, and that pharmacologic activation of TrkB would improve respiratory function. We characterized BDNF protein expression, TrkB activation and respiration in heterozygous female Mecp2 mutant mice (Het), a model that recapitulates the somatic mosaicism for mutant MECP2 found in typical RTT patients, and evaluated the ability of a small molecule TrkB agonist, LM22A-4, to ameliorate biochemical and functional abnormalities in these animals. We found that Het mice exhibit (1) reduced BDNF expression and TrkB activation in the medulla and pons and (2) breathing dysfunction, characterized by increased frequency due to periods of tachypnea, and increased apneas, as in RTT patients. Treatment of Het mice with LM22A-4 for 4 weeks rescued wild-type levels of TrkB phosphorylation in the medulla and pons and restored wild-type breathing frequency. These data provide new insight into the role of BDNF signaling deficits in the pathophysiology of RTT and highlight TrkB as a possible therapeutic target in this disease.
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Affiliation(s)
- Danielle A. Schmid
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Tao Yang
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California 94305, and
| | - Michael Ogier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Ian Adams
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Yatin Mirakhur
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Qifang Wang
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Stephen M. Massa
- Department of Neurology and Laboratory for Computational Neurochemistry and Drug Discovery, San Francisco Veterans Affairs Medical Center, and Department of Neurology, University of California, San Francisco, California 94121
| | - Frank M. Longo
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California 94305, and
| | - David M. Katz
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
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Zhang X, Su J, Cui N, Gai H, Wu Z, Jiang C. The disruption of central CO2 chemosensitivity in a mouse model of Rett syndrome. Am J Physiol Cell Physiol 2011; 301:C729-38. [PMID: 21307341 PMCID: PMC3174562 DOI: 10.1152/ajpcell.00334.2010] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Accepted: 02/07/2011] [Indexed: 01/14/2023]
Abstract
People with Rett syndrome (RTT) have breathing instability in addition to other neuropathological manifestations. The breathing disturbances contribute to the high incidence of unexplained death and abnormal brain development. However, the cellular mechanisms underlying the breathing abnormalities remain unclear. To test the hypothesis that the central CO(2) chemoreception in these people is disrupted, we studied the CO(2) chemosensitivity in a mouse model of RTT. The Mecp2-null mice showed a selective loss of their respiratory response to 1-3% CO(2) (mild hypercapnia), whereas they displayed more regular breathing in response to 6-9% CO(2) (severe hypercapnia). The defect was alleviated with the NE uptake blocker desipramine (10 mg·kg(-1)·day(-1) ip, for 5-7 days). Consistent with the in vivo observations, in vitro studies in brain slices indicated that CO(2) chemosensitivity of locus coeruleus (LC) neurons was impaired in Mecp2-null mice. Two major neuronal pH-sensitive Kir currents that resembled homomeric Kir4.1 and heteromeric Ki4.1/Kir5.1 channels were identified in the LC neurons. The screening of Kir channels with real-time PCR indicated the overexpression of Kir4.1 in the LC region of Mecp2-null mice. In a heterologous expression system, an overexpression of Kir4.1 resulted in a reduction in the pH sensitivity of the heteromeric Kir4.1-Kir5.1 channels. Given that Kir4.1 and Kir5.1 subunits are also expressed in brain stem respiration-related areas, the Kir4.1 overexpression may not allow CO(2) to be detected until hypercapnia becomes severe, leading to periodical hyper- and hypoventilation in Mecp2-null mice and, perhaps, in people with RTT as well.
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Affiliation(s)
- Xiaoli Zhang
- Dept. of Biology, Georgia State Univ., Atlanta, 30303, USA
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Hagebeuk EEO, Koelman JHTM, Duran M, Abeling NG, Vyth A, Poll-The BT. Clinical and electroencephalographic effects of folinic acid treatment in Rett syndrome patients. J Child Neurol 2011; 26:718-23. [PMID: 21427443 DOI: 10.1177/0883073810390037] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Rett syndrome is characterized by the development of stereotypic hand movements and seizures, which are often difficult to treat. Previous studies have shown conflicting results during add-on folinic acid. Here, the authors reevaluate the response to folinic acid in terms of epilepsy control and electroencephalography features. They performed a randomized, placebo-controlled, double-blind crossover trial, with a follow-up of more than 2 years. Twelve girls with Rett syndrome participated, comparable in clinical stage and disease severity. The Rett syndrome patients were given either folinic acid or placebo, for 1 year each. Only 3 girls benefited to some extent: 2 had a reduction and/or decrease in seizures, and all 3 showed some decreased epileptiform activity on electroencephalography during the addition of folinic acid. Despite this, antiepileptic drugs were adjusted. Because the effect of added folinic acid was limited and did not prevent antiepileptic drug increase, the authors do not recommend adding on folinic acid in Rett syndrome girls with epilepsy.
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Affiliation(s)
- Eveline E O Hagebeuk
- Academical Medical Center, Department of Paediatric Neurology, Amsterdam, the Netherlands.
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Rare diseases offer insights into autism spectrum disorders. Preliminary laboratory studies suggest new biological targets for intervention. Harv Ment Health Lett 2009; 25:3. [PMID: 19475765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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45
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Chen W, Liao JX, Chen L. [Rett syndrome in a child treated with adrenocorticotrophic hormone]. Zhongguo Dang Dai Er Ke Za Zhi 2009; 11:235-6. [PMID: 19292970 DOI: pmid/19292970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Doppler E, Rockenstein E, Ubhi K, Inglis C, Mante M, Adame A, Crews L, Hitzl M, Moessler H, Masliah E. Neurotrophic effects of Cerebrolysin in the Mecp2(308/Y) transgenic model of Rett syndrome. Acta Neuropathol 2008; 116:425-37. [PMID: 18600331 DOI: 10.1007/s00401-008-0407-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Revised: 06/13/2008] [Accepted: 06/14/2008] [Indexed: 02/07/2023]
Abstract
Rett syndrome is a childhood neurodevelopmental disorder caused by mutations in the gene encoding for methyl-CpG-binding protein (MeCP2). Neuropathological studies in patients with Rett syndrome and in MeCP2 mutant models have shown reduced dendritic arborization and abnormal neuronal packing. We have previously shown that Cerebrolysin (CBL), a neurotrophic peptide mixture, ameliorates the synaptic and dendritic pathology in models of aging and neurodegeneration. This study aimed to determine whether CBL was capable of reducing behavioral and neuronal alterations in Mecp2(308/Y) mutant mice. Two sets of experiments were performed, the first with 4-month-old male Mecp2(308/Y) mutant mice treated with CBL or vehicle for 3 months (Group A) and the second with 1-month-old mice treated for 6 months (Group B). Behavioral analysis showed improved motor performance with CBL in Group A and a trend toward improvement in Group B. Consistent with behavioral findings, neuropathological analysis of the basal ganglia showed amelioration of dendritic simplification in CBL-treated Mecp2(308/Y) mutant mice. CBL treatment also ameliorated dendritic pathology and neuronal loss in the hippocampus and neocortex in Mecp2(308/Y) mutant mice. In conclusion, this study demonstrates that CBL promotes recovery of dendritic and neuronal damage and behavioral improvements in young adult Mecp2(308/Y) mutant mice and suggests that CBL may have neurotrophic effects in this model. These findings support the possibility that CBL may have beneficial effects in the management of Rett syndrome.
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Affiliation(s)
- Edith Doppler
- EBEWE Pharmaceuticals, Research Division, Unterach, Austria
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Abstract
Recent progress in our understanding of Rett syndrome has been dramatic. Against the background that the clinical features of Rett syndrome may be reversible, in part or in whole, substantial optimism has emerged regarding possible therapies. As such, it is timely to update recent research progress. This update summarizes research advances during the past 18 to 24 months in terms of clinical and translational research, as well as basic research.
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Affiliation(s)
- Alan K Percy
- Department of Pediatrics, University of Alabama at Birmingham, AL 35294-0021, USA.
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Zanella S, Mebarek S, Lajard AM, Picard N, Dutschmann M, Hilaire G. Oral treatment with desipramine improves breathing and life span in Rett syndrome mouse model. Respir Physiol Neurobiol 2008; 160:116-21. [PMID: 17905670 DOI: 10.1016/j.resp.2007.08.009] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Revised: 08/20/2007] [Accepted: 08/24/2007] [Indexed: 11/22/2022]
Abstract
Rett syndrome is a neurodevelopmental disease due to Mecp2 gene mutations that is associated to complex neurological symptoms, with bioaminergic deficits and life-threatening apneas related to sudden and unexpected death. In male mice, Mecp2-deficiency similarly induces medullary bioaminergic deficits, severe apneas and short life span. Here, we show that long-term oral treatment of Mecp2-deficient male mice with desipramine, an old drug of clinical use known to block norepinephrine uptake and to strengthen its synaptic effects, significantly alleviates their breathing symptoms and prolongs their life span. Although these mouse results identify desipramine as the first oral pharmacological treatment potentially able to alleviate breathing symptoms of Rett syndrome, we recommend further studies of desipramine effects in Mecp2-deficient mice before attempting any clinical trials in Rett patients.
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Affiliation(s)
- Sébastien Zanella
- MP3-Respiration, UMR CNRS 6153, 280 Boulevard Sainte Marguerite, 13009 Marseille, France
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Ogier M, Wang H, Hong E, Wang Q, Greenberg ME, Katz DM. Brain-derived neurotrophic factor expression and respiratory function improve after ampakine treatment in a mouse model of Rett syndrome. J Neurosci 2007; 27:10912-7. [PMID: 17913925 PMCID: PMC6672830 DOI: 10.1523/jneurosci.1869-07.2007] [Citation(s) in RCA: 192] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Rett syndrome (RTT) is caused by loss-of-function mutations in the gene encoding methyl-CpG-binding protein 2 (MeCP2). Although MeCP2 is thought to act as a transcriptional repressor of brain-derived neurotrophic factor (BDNF), Mecp2 null mice, which develop an RTT-like phenotype, exhibit progressive deficits in BDNF expression. These deficits are particularly significant in the brainstem and nodose cranial sensory ganglia (NGs), structures critical for cardiorespiratory homeostasis, and may be linked to the severe respiratory abnormalities characteristic of RTT. Therefore, the present study used Mecp2 null mice to further define the role of MeCP2 in regulation of BDNF expression and neural function, focusing on NG neurons and respiratory control. We find that mutant neurons express significantly lower levels of BDNF than wild-type cells in vitro, as in vivo, under both depolarizing and nondepolarizing conditions. However, BDNF levels in mutant NG cells can be increased by chronic depolarization in vitro or by treatment of Mecp2 null mice with CX546, an ampakine drug that facilitates activation of glutamatergic AMPA receptors. Ampakine-treated Mecp2 null mice also exhibit marked functional improvement, characterized by restoration of normal breathing frequency and minute volume. These data demonstrate that BDNF expression remains plastic in Mecp2 null mice and raise the possibility that ampakine compounds could be of therapeutic value in the treatment of RTT.
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Affiliation(s)
- Michael Ogier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, and
| | - Hong Wang
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, and
| | - Elizabeth Hong
- Departments of Neurology and Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Qifang Wang
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, and
| | - Michael E. Greenberg
- Departments of Neurology and Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - David M. Katz
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, and
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Penning C, van der Wouden JC. Increased plasma leptin levels and valproate use in patients with Rett syndrome. J Pediatr 2007; 151:e15; author reply e15. [PMID: 17889056 DOI: 10.1016/j.jpeds.2007.06.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Accepted: 06/19/2007] [Indexed: 11/18/2022]
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