1
|
Valencia ML, Sofela FA, Jongens TA, Sehgal A. Do metabolic deficits contribute to sleep disruption in monogenic intellectual disability syndromes? Trends Neurosci 2024; 47:583-592. [PMID: 39054162 DOI: 10.1016/j.tins.2024.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/28/2024] [Accepted: 06/26/2024] [Indexed: 07/27/2024]
Abstract
Intellectual disability is defined as limitations in cognitive and adaptive behavior that often arise during development. Disordered sleep is common in intellectual disability and, given the importance of sleep for cognitive function, it may contribute to other behavioral phenotypes. Animal models of intellectual disability, in particular of monogenic intellectual disability syndromes (MIDS), recapitulate many disease phenotypes and have been invaluable for linking some of these phenotypes to specific molecular pathways. An emerging feature of MIDS, in both animal models and humans, is the prevalence of metabolic abnormalities, which could be relevant for behavior. Focusing on specific MIDS that have been molecularly characterized, we review sleep, circadian, and metabolic phenotypes in animal models and humans and propose that altered metabolic state contributes to the abnormal sleep/circadian phenotypes in MIDS.
Collapse
Affiliation(s)
- Mariela Lopez Valencia
- Chronobiology and Sleep Institute, Perelman Medical School of University of Pennsylvania, Philadelphia, PA, USA
| | - Folasade A Sofela
- Chronobiology and Sleep Institute, Perelman Medical School of University of Pennsylvania, Philadelphia, PA, USA
| | - Thomas A Jongens
- Chronobiology and Sleep Institute, Perelman Medical School of University of Pennsylvania, Philadelphia, PA, USA; Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA; Autism Spectrum Program of Excellence, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Amita Sehgal
- Chronobiology and Sleep Institute, Perelman Medical School of University of Pennsylvania, Philadelphia, PA, USA; Howard Hughes Medical Institute, Philadelphia, PA, USA.
| |
Collapse
|
2
|
Heimdörfer D, Vorleuter A, Eschlböck A, Spathopoulou A, Suarez-Cubero M, Farhan H, Reiterer V, Spanjaard M, Schaaf CP, Huber LA, Kremser L, Sarg B, Edenhofer F, Geley S, de Araujo MEG, Huettenhofer A. Truncated variants of MAGEL2 are involved in the etiologies of the Schaaf-Yang and Prader-Willi syndromes. Am J Hum Genet 2024; 111:1383-1404. [PMID: 38908375 PMCID: PMC11267527 DOI: 10.1016/j.ajhg.2024.05.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/27/2024] [Accepted: 05/29/2024] [Indexed: 06/24/2024] Open
Abstract
The neurodevelopmental disorders Prader-Willi syndrome (PWS) and Schaaf-Yang syndrome (SYS) both arise from genomic alterations within human chromosome 15q11-q13. A deletion of the SNORD116 cluster, encoding small nucleolar RNAs, or frameshift mutations within MAGEL2 result in closely related phenotypes in individuals with PWS or SYS, respectively. By investigation of their subcellular localization, we observed that in contrast to a predominant cytoplasmic localization of wild-type (WT) MAGEL2, a truncated MAGEL2 mutant was evenly distributed between the cytoplasm and the nucleus. To elucidate regulatory pathways that may underlie both diseases, we identified protein interaction partners for WT or mutant MAGEL2, in particular the survival motor neuron protein (SMN), involved in spinal muscular atrophy, and the fragile-X-messenger ribonucleoprotein (FMRP), involved in autism spectrum disorders. The interactome of the non-coding RNA SNORD116 was also investigated by RNA-CoIP. We show that WT and truncated MAGEL2 were both involved in RNA metabolism, while regulation of transcription was mainly observed for WT MAGEL2. Hence, we investigated the influence of MAGEL2 mutations on the expression of genes from the PWS locus, including the SNORD116 cluster. Thereby, we provide evidence for MAGEL2 mutants decreasing the expression of SNORD116, SNORD115, and SNORD109A, as well as protein-coding genes MKRN3 and SNRPN, thus bridging the gap between PWS and SYS.
Collapse
Affiliation(s)
- David Heimdörfer
- Institute of Genomics and RNomics, Biocenter Innsbruck, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Alexander Vorleuter
- Institute of Genomics and RNomics, Biocenter Innsbruck, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Alexander Eschlböck
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Angeliki Spathopoulou
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Marta Suarez-Cubero
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Hesso Farhan
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Veronika Reiterer
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Melanie Spanjaard
- Institute of Human Genetics, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Christian P Schaaf
- Institute of Human Genetics, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Lukas A Huber
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innrain 80/82, Innsbruck 6020, Austria
| | - Leopold Kremser
- Institute of Medical Biochemistry, Protein Core Facility, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Bettina Sarg
- Institute of Medical Biochemistry, Protein Core Facility, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Frank Edenhofer
- Institute for Molecular Biology, Genomics, Stem Cell Biology & Regenerative Medicine Group, University of Innsbruck and CMBI, Technikerstr. 25, 6020 Innsbruck, Austria
| | - Stephan Geley
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Mariana E G de Araujo
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innrain 80/82, Innsbruck 6020, Austria
| | - Alexander Huettenhofer
- Institute of Genomics and RNomics, Biocenter Innsbruck, Medical University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| |
Collapse
|
3
|
Dionne O, Abolghasemi A, Corbin F, Çaku A. Implication of the endocannabidiome and metabolic pathways in fragile X syndrome pathophysiology. Psychiatry Res 2024; 337:115962. [PMID: 38763080 DOI: 10.1016/j.psychres.2024.115962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 05/10/2024] [Accepted: 05/11/2024] [Indexed: 05/21/2024]
Abstract
Fragile X Syndrome (FXS) results from the silencing of the FMR1 gene and is the most prevalent inherited cause of intellectual disability and the most frequent monogenic cause of autism spectrum disorder. It is well established that Fragile X individuals are subjected to a wide array of comorbidities, ranging from cognitive, behavioural, and medical origin. Furthermore, recent studies have also described metabolic impairments in FXS individuals. However, the molecular mechanisms linking FMRP deficiency to improper metabolism are still misunderstood. The endocannabinoidome (eCBome) is a lipid-based signalling system that regulates several functions across the body, ranging from cognition, behaviour and metabolism. Alterations in the eCBome have been described in FXS animal models and linked to neuronal hyperexcitability, a core deficit of the disease. However, the potential link between dysregulation of the eCBome and altered metabolism observed in FXS remains unexplored. As such, this review aims to overcome this issue by describing the most recent finding related to eCBome and metabolic dysfunctions in the context of FXS. A better comprehension of this association will help deepen our understanding of FXS pathophysiology and pave the way for future therapeutic interventions.
Collapse
Affiliation(s)
- Olivier Dionne
- Biochemistry and Functional Genomic Department, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Canada.
| | - Armita Abolghasemi
- Biochemistry and Functional Genomic Department, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Canada
| | - François Corbin
- Biochemistry and Functional Genomic Department, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Canada
| | - Artuela Çaku
- Biochemistry and Functional Genomic Department, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Canada
| |
Collapse
|
4
|
Andrews SM, Panjwani AA, Potter SN, Hamrick LR, Wheeler AC, Kelleher BL. Specificity of Early Childhood Hyperphagia Profiles in Neurogenetic Conditions. AMERICAN JOURNAL ON INTELLECTUAL AND DEVELOPMENTAL DISABILITIES 2024; 129:175-190. [PMID: 38657964 DOI: 10.1352/1944-7558-129.3.175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 10/10/2023] [Indexed: 04/26/2024]
Abstract
Hyperphagia is highly penetrant in Prader-Willi syndrome (PWS) and has increasingly been reported in other neurogenetic conditions (NGC). The Hyperphagia Questionnaire (HQ) was completed by caregivers of 4-8-year-olds with PWS (n = 17), Angelman syndrome (AS; n = 22), Williams syndrome (WS; n = 25), or low-risk controls (LRC; n = 35). All NGC groups were significantly elevated in HQ Total and Behavior scores compared to LRC. Only AS and WS were significantly elevated in the Drive domain, and only PWS in the Severity domain. After controlling for externalizing behavior, HQ Total scores were higher for PWS relative to other groups. Hyperphagic symptoms may not differentiate PWS from other NGCs in early childhood. However, hyperphagic phenotypes may be most severe in PWS. Further investigation of these profiles may inform etiology and syndrome-specific treatments.
Collapse
|
5
|
Aishworiya R, Tak Y, Ponzini MD, Biag HMB, Salcedo-Arellano MJ, Kim K, Tassone F, Schneider A, Thurman AJ, Abbeduto L, Hessl D, Randol JL, Bolduc FV, Lippe S, Hagerman P, Hagerman R. Adaptive, behavioral, and cognitive outcomes in individuals with fragile X syndrome with varying autism severity. Int J Dev Neurosci 2023; 83:715-727. [PMID: 37724826 PMCID: PMC10868665 DOI: 10.1002/jdn.10299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 08/06/2023] [Accepted: 08/31/2023] [Indexed: 09/21/2023] Open
Abstract
This study aimed to determine the association between severity of autism spectrum disorder (ASD) and cognitive, behavioral, and molecular measures in individuals with fragile X syndrome (FXS). Study inclusion criteria included individuals with FXS and (1) age 6-40 years, (2) full-scale IQ < 84, and (3) language ≥3-word phrases. ASD symptom severity was determined by Autism Diagnostic Observation Schedule-2 (ADOS-2). Other measures identified non-verbal IQ, adaptive skills, and aberrant behaviors. Molecular measures included blood FMR1 and CYFIP1 mRNA levels, FMRP and MMP9 levels. Analysis of variance (ANOVA) and Spearman's correlations were used to compare ASD severity groups. Data from 54 individuals was included with no/mild (N = 7), moderate (N = 18), and severe (N = 29) ASD. Individuals with high ASD severity had lower adaptive behavior scores (47.48 ± 17.49) than the no/mild group (69.00 ± 20.45, p = 0.0366); they also had more challenging behaviors, lethargy, and stereotypic behaviors. CYFIP1 mRNA expression levels positively correlated with the ADOS-2 comparison score(r2 = 0.33, p = 0.0349), with no significant correlations with other molecular markers. In conclusion, autism symptom severity is associated with more adverse cognitive and adaptive skills and specific behaviors in FXS, whereas CYFIP1 mRNA expression levels may be a potential biomarker for severity of ASD in FXS.
Collapse
Affiliation(s)
- Ramkumar Aishworiya
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Khoo Teck Puat-National University Children’s Medical Institute, National University Health System, Singapore
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - YeEun Tak
- University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Matthew Dominic Ponzini
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Public Health Sciences, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Hazel Maridith Barlahan Biag
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Maria Jimena Salcedo-Arellano
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Kyoungmi Kim
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Public Health Sciences, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Angela John Thurman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Leonard Abbeduto
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - David Hessl
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Jamie Leah Randol
- University of California Davis School of Medicine, Sacramento, California, United States of America
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, California, United States of America
- Integrative Genetics and Genomics Graduate Group, University of California Davis, One Shields Avenue, Davis, California, United States of America
- UC Davis Biotechnology Program, University of California Davis, Davis, California, United States of America
| | - Francois V Bolduc
- Division of Pediatric Neurology, Pediatrics, University of Alberta, Alberta, Canada
- Division of Medical Genetics, University of Alberta, Alberta, Canada
| | - Sarah Lippe
- Département de Psychologie, Université de Montréal, Québec, Canada
- CHU Sainte-Justine Research Center, Université de Montréal, Québec, Canada
| | - Paul Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- University of California Davis School of Medicine, Sacramento, California, United States of America
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, California, United States of America
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, California, United States of America
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, California, United States of America
| |
Collapse
|
6
|
Aishworiya R, Chi MH, Zafarullah M, Mendoza G, Ponzini MD, Kim K, Biag HMB, Thurman AJ, Abbeduto L, Hessl D, Randol JL, Bolduc FV, Jacquemont S, Lippé S, Hagerman P, Hagerman R, Schneider A, Tassone F. Intercorrelation of Molecular Biomarkers and Clinical Phenotype Measures in Fragile X Syndrome. Cells 2023; 12:1920. [PMID: 37508583 PMCID: PMC10377864 DOI: 10.3390/cells12141920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/05/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
This study contributes to a greater understanding of the utility of molecular biomarkers to identify clinical phenotypes of fragile X syndrome (FXS). Correlations of baseline clinical trial data (molecular measures-FMR1 mRNA, CYFIP1 mRNA, MMP9 and FMRP protein expression levels, nonverbal IQ, body mass index and weight, language level, NIH Toolbox, adaptive behavior rating, autism, and other mental health correlates) of 59 participants with FXS ages of 6-32 years are reported. FMR1 mRNA expression levels correlated positively with adaptive functioning levels, expressive language, and specific NIH Toolbox measures. The findings of a positive correlation of MMP-9 levels with obesity, CYFIP1 mRNA with mood and autistic symptoms, and FMR1 mRNA expression level with better cognitive, language, and adaptive functions indicate potential biomarkers for specific FXS phenotypes. These may be potential markers for future clinical trials for targeted treatments of FXS.
Collapse
Affiliation(s)
- Ramkumar Aishworiya
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Khoo Teck Puat-National University Children’s Medical Institute, National University Health System, Singapore 119074, Singapore
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
| | - Mei-Hung Chi
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Psychiatry, National Cheng Kung University Hospital, Tainan 704, Taiwan
| | - Marwa Zafarullah
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA (G.M.)
| | - Guadalupe Mendoza
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA (G.M.)
| | - Matthew Dominic Ponzini
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Public Health Sciences, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Kyoungmi Kim
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Public Health Sciences, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Hazel Maridith Barlahan Biag
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Pediatrics, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Angela John Thurman
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Leonard Abbeduto
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - David Hessl
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Jamie Leah Randol
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA (G.M.)
- Integrative Genetics and Genomics Graduate Group, University of California Davis, One Shields Avenue, Davis, CA 95616, USA
- UC Davis Biotechnology Program, University of California Davis, Davis, CA 95616, USA
| | - Francois V. Bolduc
- Department of Pediatrics, Department of Medical Genetics, Women and Children Health Research Institute, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Sebastien Jacquemont
- CHU Sainte-Justine Research Center, Université de Montréal, Montreal, QC H3T 1J4, Canada
- Department of Pediatrics, University of Montreal, Montreal, QC H3T 1J4, Canada
| | - Sarah Lippé
- CHU Sainte-Justine Research Center, Université de Montréal, Montreal, QC H3T 1J4, Canada
- Department of Psychology, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Paul Hagerman
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA (G.M.)
| | - Randi Hagerman
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Pediatrics, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Andrea Schneider
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Pediatrics, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Flora Tassone
- MIND Institute, University of California Davis Medical Center, Sacramento, CA 95817, USA; (R.A.); (M.D.P.); (H.M.B.B.)
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA (G.M.)
| |
Collapse
|
7
|
Mahmoud R, Kimonis V, Butler MG. Genetics of Obesity in Humans: A Clinical Review. Int J Mol Sci 2022; 23:11005. [PMID: 36232301 PMCID: PMC9569701 DOI: 10.3390/ijms231911005] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/09/2022] [Accepted: 09/10/2022] [Indexed: 11/23/2022] Open
Abstract
Obesity is a complex multifactorial disorder with genetic and environmental factors. There is an increase in the worldwide prevalence of obesity in both developed and developing countries. The development of genome-wide association studies (GWAS) and next-generation sequencing (NGS) has increased the discovery of genetic associations and awareness of monogenic and polygenic causes of obesity. The genetics of obesity could be classified into syndromic and non-syndromic obesity. Prader-Willi, fragile X, Bardet-Biedl, Cohen, and Albright Hereditary Osteodystrophy (AHO) syndromes are examples of syndromic obesity, which are associated with developmental delay and early onset obesity. Non-syndromic obesity could be monogenic, polygenic, or chromosomal in origin. Monogenic obesity is caused by variants of single genes while polygenic obesity includes several genes with the involvement of members of gene families. New advances in genetic testing have led to the identification of obesity-related genes. Leptin (LEP), the leptin receptor (LEPR), proopiomelanocortin (POMC), prohormone convertase 1 (PCSK1), the melanocortin 4 receptor (MC4R), single-minded homolog 1 (SIM1), brain-derived neurotrophic factor (BDNF), and the neurotrophic tyrosine kinase receptor type 2 gene (NTRK2) have been reported as causative genes for obesity. NGS is now in use and emerging as a useful tool to search for candidate genes for obesity in clinical settings.
Collapse
Affiliation(s)
- Ranim Mahmoud
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
- Department of Pediatrics, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Virginia Kimonis
- Department of Pediatrics, University of California, Irvine, CA 92697, USA
- Departments of Neurology and Pathology, University of California, Irvine, CA 92697, USA
- Children’s Hospital of Orange County, Orange, CA 92868, USA
| | - Merlin G. Butler
- Departments of Psychiatry & Behavioral Sciences and Pediatrics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| |
Collapse
|
8
|
Triantopoulou N, Vidaki M. Local mRNA translation and cytoskeletal reorganization: Mechanisms that tune neuronal responses. Front Mol Neurosci 2022; 15:949096. [PMID: 35979146 PMCID: PMC9376447 DOI: 10.3389/fnmol.2022.949096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 07/07/2022] [Indexed: 12/31/2022] Open
Abstract
Neurons are highly polarized cells with significantly long axonal and dendritic extensions that can reach distances up to hundreds of centimeters away from the cell bodies in higher vertebrates. Their successful formation, maintenance, and proper function highly depend on the coordination of intricate molecular networks that allow axons and dendrites to quickly process information, and respond to a continuous and diverse cascade of environmental stimuli, often without enough time for communication with the soma. Two seemingly unrelated processes, essential for these rapid responses, and thus neuronal homeostasis and plasticity, are local mRNA translation and cytoskeletal reorganization. The axonal cytoskeleton is characterized by high stability and great plasticity; two contradictory attributes that emerge from the powerful cytoskeletal rearrangement dynamics. Cytoskeletal reorganization is crucial during nervous system development and in adulthood, ensuring the establishment of proper neuronal shape and polarity, as well as regulating intracellular transport and synaptic functions. Local mRNA translation is another mechanism with a well-established role in the developing and adult nervous system. It is pivotal for axonal guidance and arborization, synaptic formation, and function and seems to be a key player in processes activated after neuronal damage. Perturbations in the regulatory pathways of local translation and cytoskeletal reorganization contribute to various pathologies with diverse clinical manifestations, ranging from intellectual disabilities (ID) to autism spectrum disorders (ASD) and schizophrenia (SCZ). Despite the fact that both processes are essential for the orchestration of pathways critical for proper axonal and dendritic function, the interplay between them remains elusive. Here we review our current knowledge on the molecular mechanisms and specific interaction networks that regulate and potentially coordinate these interconnected processes.
Collapse
Affiliation(s)
- Nikoletta Triantopoulou
- Division of Basic Sciences, Medical School, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas (IMBB-FORTH), Heraklion, Greece
| | - Marina Vidaki
- Division of Basic Sciences, Medical School, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology Hellas (IMBB-FORTH), Heraklion, Greece
- *Correspondence: Marina Vidaki,
| |
Collapse
|
9
|
Choo TH, Xu Q, Budimirovic D, Lozano R, Esler AN, Frye RE, Andrews H, Velinov M. Height and BMI in fragile X syndrome: A longitudinal assessment. Obesity (Silver Spring) 2022; 30:743-750. [PMID: 35174658 PMCID: PMC11047757 DOI: 10.1002/oby.23368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 12/01/2021] [Accepted: 12/03/2021] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Previously reported data regarding growth parameters in individuals with fragile X syndrome (FXS) are inconsistent. A longitudinal analysis of height and BMI in a large number of individuals with FXS was conducted. METHODS Age- and sex-specific z scores for height and BMI of 1,223 individuals with FXS were calculated based on published normative data. Mixed-effect linear regression models were fit separately for males and females, and z scores for height and weight were regressed against age and adjusted for intellectual disability (ID) and psychotropic medication use. RESULTS Mean height z score for both sexes decreased with age and was lower than normative data. Mean BMI z score was greater than normative data in both sexes, and this disparity increased with age. BMI z score in females was greater for those with moderate or severe ID than those with no or mild ID. Individuals taking antipsychotics had higher BMI z scores than those taking no or other medications; those taking anticonvulsants or stimulants had lower BMI z scores. CONCLUSIONS Individuals with FXS are at elevated risk for overweight and obesity. The risk is higher in individuals taking antipsychotics and among females with severe ID. These findings warrant increased attention to obesity prevention for all individuals with FXS.
Collapse
Affiliation(s)
- Tse-Hwei Choo
- Department of Psychiatry, Columbia University, New York, New York, USA
| | - Qing Xu
- Department of Psychiatry, Columbia University, New York, New York, USA
| | - Dejan Budimirovic
- Department of Psychiatry, Fragile X Clinic, Kennedy Krieger Institute/JHMI, Baltimore, Maryland, USA
- Department of Psychiatry and Behavioral Sciences-Child Psychiatry, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Reymundo Lozano
- Department of Genetics and Genomic Sciences, Pediatrics and Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Amy N Esler
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Richard E Frye
- Section of Neurodevelopmental Disorders, Barrow Neurological Institute at Phoenix Children's Hospital, Phoenix, Arizona, USA
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, Arizona, USA
| | - Howard Andrews
- Data Coordinating Center, Columbia University-Mailman School of Public Health, New York State Psychiatric Institute, New York, New York, USA
| | - Milen Velinov
- Department of Pediatrics, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA
| |
Collapse
|
10
|
Juriaans AF, Kerkhof GF, Hokken-Koelega ACS. The Spectrum of the Prader-Willi-like Pheno- and Genotype: A Review of the Literature. Endocr Rev 2022; 43:1-18. [PMID: 34460908 DOI: 10.1210/endrev/bnab026] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Indexed: 12/16/2022]
Abstract
Prader-Willi syndrome (PWS) is a rare genetic syndrome, caused by the loss of expression of the paternal chromosome 15q11-q13 region. Over the past years, many cases of patients with characteristics similar to PWS, but without a typical genetic aberration of the 15q11-q13 region, have been described. These patients are often labelled as Prader-Willi-like (PWL). PWL is an as-yet poorly defined syndrome, potentially affecting a significant number of children and adults. In the current clinical practice, patients labelled as PWL are mostly left without treatment options. Considering the similarities with PWS, children with PWL might benefit from the same care and treatment as children with PWS. This review gives more insight into the pheno- and genotype of PWL and includes 86 papers, containing 368 cases of patients with a PWL phenotype. We describe mutations and aberrations for consideration when suspicion of PWS remains after negative testing. The most common genetic diagnoses were Temple syndrome (formerly known as maternal uniparental disomy 14), Schaaf-Yang syndrome (truncating mutation in the MAGEL2 gene), 1p36 deletion, 2p deletion, 6q deletion, 6q duplication, 15q deletion, 15q duplication, 19p deletion, fragile X syndrome, and Xq duplication. We found that the most prevalent symptoms in the entire group were developmental delay/intellectual disability (76%), speech problems (64%), overweight/obesity (57%), hypotonia (56%), and psychobehavioral problems (53%). In addition, we propose a diagnostic approach to patients with a PWL phenotype for (pediatric) endocrinologists. PWL comprises a complex and diverse group of patients, which calls for multidisciplinary care with an individualized approach.
Collapse
Affiliation(s)
- Alicia F Juriaans
- National Reference Center for Prader-Willi Syndrome and Prader-Willi-like, The Netherlands.,Department of Pediatrics, Subdivision of Endocrinology, Erasmus Medical Center, The Netherlands.,Dutch Growth Research Foundation, Rotterdam, The Netherlands
| | - Gerthe F Kerkhof
- National Reference Center for Prader-Willi Syndrome and Prader-Willi-like, The Netherlands.,Department of Pediatrics, Subdivision of Endocrinology, Erasmus Medical Center, The Netherlands
| | - Anita C S Hokken-Koelega
- National Reference Center for Prader-Willi Syndrome and Prader-Willi-like, The Netherlands.,Department of Pediatrics, Subdivision of Endocrinology, Erasmus Medical Center, The Netherlands.,Dutch Growth Research Foundation, Rotterdam, The Netherlands
| |
Collapse
|
11
|
Baldini L, Robert A, Charpentier B, Labialle S. Phylogenetic and molecular analyses identify SNORD116 targets involved in the Prader Willi syndrome. Mol Biol Evol 2021; 39:6454102. [PMID: 34893870 PMCID: PMC8789076 DOI: 10.1093/molbev/msab348] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The eutherian-specific SNORD116 family of repeated box C/D snoRNA genes is suspected to play a major role in the Prader–Willi syndrome (PWS), yet its molecular function remains poorly understood. Here, we combined phylogenetic and molecular analyses to identify candidate RNA targets. Based on the analysis of several eutherian orthologs, we found evidence of extensive birth-and-death and conversion events during SNORD116 gene history. However, the consequences for phylogenetic conservation were heterogeneous along the gene sequence. The standard snoRNA elements necessary for RNA stability and association with dedicated core proteins were the most conserved, in agreement with the hypothesis that SNORD116 generate genuine snoRNAs. In addition, one of the two antisense elements typically involved in RNA target recognition was largely dominated by a unique sequence present in at least one subset of gene paralogs in most species, likely the result of a selective effect. In agreement with a functional role, this ASE exhibited a hybridization capacity with putative mRNA targets that was strongly conserved in eutherians. Moreover, transient downregulation experiments in human cells showed that Snord116 controls the expression and splicing levels of these mRNAs. The functions of two of them, diacylglycerol kinase kappa and Neuroligin 3, extend the description of the molecular bases of PWS and reveal unexpected molecular links with the Fragile X syndrome and autism spectrum disorders.
Collapse
Affiliation(s)
- Laeya Baldini
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
| | - Anne Robert
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
| | | | | |
Collapse
|
12
|
Romagnoli A, Di Marino D. The Use of Peptides in the Treatment of Fragile X Syndrome: Challenges and Opportunities. Front Psychiatry 2021; 12:754485. [PMID: 34803767 PMCID: PMC8599826 DOI: 10.3389/fpsyt.2021.754485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/11/2021] [Indexed: 01/17/2023] Open
Abstract
Fragile X Syndrome (FXS) is the most frequent cause of inherited intellectual disabilities and autism spectrum disorders, characterized by cognitive deficits and autistic behaviors. The silencing of the Fmr1 gene and consequent lack of FMRP protein, is the major contribution to FXS pathophysiology. FMRP is an RNA binding protein involved in the maturation and plasticity of synapses and its absence culminates in a range of morphological, synaptic and behavioral phenotypes. Currently, there are no approved medications for the treatment of FXS, with the approaches under study being fairly specific and unsatisfying in human trials. Here we propose peptides/peptidomimetics as candidates in the pharmacotherapy of FXS; in the last years this class of molecules has catalyzed the attention of pharmaceutical research, being highly selective and well-tolerated. Thanks to their ability to target protein-protein interactions (PPIs), they are already being tested for a wide range of diseases, including cancer, diabetes, inflammation, Alzheimer's disease, but this approach has never been applied to FXS. As FXS is at the forefront of efforts to develop new drugs and approaches, we discuss opportunities, challenges and potential issues of peptides/peptidomimetics in FXS drug design and development.
Collapse
Affiliation(s)
| | - Daniele Di Marino
- Department of Life and Environmental Sciences, New York-Marche Structural Biology Center (NY-MaSBiC), Polytechnic University of Marche, Ancona, Italy
| |
Collapse
|
13
|
Salcedo-Arellano MJ, Cabal-Herrera AM, Punatar RH, Clark CJ, Romney CA, Hagerman RJ. Overlapping Molecular Pathways Leading to Autism Spectrum Disorders, Fragile X Syndrome, and Targeted Treatments. Neurotherapeutics 2021; 18:265-283. [PMID: 33215285 PMCID: PMC8116395 DOI: 10.1007/s13311-020-00968-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2020] [Indexed: 02/06/2023] Open
Abstract
Autism spectrum disorders (ASD) are subdivided into idiopathic (unknown) etiology and secondary, based on known etiology. There are hundreds of causes of ASD and most of them are genetic in origin or related to the interplay of genetic etiology and environmental toxicology. Approximately 30 to 50% of the etiologies can be identified when using a combination of available genetic testing. Many of these gene mutations are either core components of the Wnt signaling pathway or their modulators. The full mutation of the fragile X mental retardation 1 (FMR1) gene leads to fragile X syndrome (FXS), the most common cause of monogenic origin of ASD, accounting for ~ 2% of the cases. There is an overlap of molecular mechanisms in those with idiopathic ASD and those with FXS, an interaction between various signaling pathways is suggested during the development of the autistic brain. This review summarizes the cross talk between neurobiological pathways found in ASD and FXS. These signaling pathways are currently under evaluation to target specific treatments in search of the reversal of the molecular abnormalities found in both idiopathic ASD and FXS.
Collapse
Affiliation(s)
- Maria Jimena Salcedo-Arellano
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, 95817, USA.
- Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, 95817, USA.
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute UCDHS, University of California Davis, 2825 50th Street, Sacramento, CA, 95817, USA.
| | - Ana Maria Cabal-Herrera
- Group on Congenital Malformations and Dysmorphology, Faculty of Health, Universidad del Valle, Cali, 00000, Colombia
| | - Ruchi Harendra Punatar
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, 95817, USA
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute UCDHS, University of California Davis, 2825 50th Street, Sacramento, CA, 95817, USA
| | - Courtney Jessica Clark
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, 95817, USA
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute UCDHS, University of California Davis, 2825 50th Street, Sacramento, CA, 95817, USA
| | - Christopher Allen Romney
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, 95817, USA
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute UCDHS, University of California Davis, 2825 50th Street, Sacramento, CA, 95817, USA
| | - Randi J Hagerman
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, 95817, USA.
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute UCDHS, University of California Davis, 2825 50th Street, Sacramento, CA, 95817, USA.
| |
Collapse
|
14
|
Blood-Based Biomarkers Predictive of Metformin Target Engagement in Fragile X Syndrome. Brain Sci 2020; 10:brainsci10060361. [PMID: 32531912 PMCID: PMC7349631 DOI: 10.3390/brainsci10060361] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/05/2020] [Accepted: 06/08/2020] [Indexed: 12/26/2022] Open
Abstract
Recent advances in neurobiology have provided several molecular entrees for targeted treatments for Fragile X syndrome (FXS). However, the efficacy of these treatments has been demonstrated mainly in animal models and has not been consistently predictive of targeted drugs' response in the preponderance of human clinical trials. Because of the heterogeneity of FXS at various levels, including the molecular level, phenotypic manifestation, and drug response, it is critically important to identify biomarkers that can help in patient stratification and prediction of therapeutic efficacy. The primary objective of this study was to assess the ability of molecular biomarkers to predict phenotypic subgroups, symptom severity, and treatment response to metformin in clinically treated patients with FXS. We specifically tested a triplex protein array comprising of hexokinase 1 (HK1), RAS (all isoforms), and Matrix Metalloproteinase 9 (MMP9) that we previously demonstrated were dysregulated in the FXS mouse model and in blood samples from patient with FXS. Seventeen participants with FXS, 12 males and 5 females, treated clinically with metformin were included in this study. The disruption in expression abundance of these proteins was normalized and associated with significant self-reported improvement in clinical phenotypes (CGI-I in addition to BMI) in a subset of participants with FXS. Our preliminary findings suggest that these proteins are of strong molecular relevance to the FXS pathology that could make them useful molecular biomarkers for this syndrome.
Collapse
|
15
|
Salcedo-Arellano MJ, Dufour B, McLennan Y, Martinez-Cerdeno V, Hagerman R. Fragile X syndrome and associated disorders: Clinical aspects and pathology. Neurobiol Dis 2020; 136:104740. [PMID: 31927143 PMCID: PMC7027994 DOI: 10.1016/j.nbd.2020.104740] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/17/2019] [Accepted: 01/08/2020] [Indexed: 12/23/2022] Open
Abstract
This review aims to assemble many years of research and clinical experience in the fields of neurodevelopment and neuroscience to present an up-to-date understanding of the clinical presentation, molecular and brain pathology associated with Fragile X syndrome, a neurodevelopmental condition that develops with the full mutation of the FMR1 gene, located in the q27.3 loci of the X chromosome, and Fragile X-associated tremor/ataxia syndrome a neurodegenerative disease experienced by aging premutation carriers of the FMR1 gene. It is important to understand that these two syndromes have a very distinct clinical and pathological presentation while sharing the same origin: the mutation of the FMR1 gene; revealing the complexity of expansion genetics.
Collapse
Affiliation(s)
- Maria Jimena Salcedo-Arellano
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, USA; Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA; Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California, Sacramento, CA, USA; Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA.
| | - Brett Dufour
- Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California, Sacramento, CA, USA; Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
| | - Yingratana McLennan
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, USA; Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA; Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California, Sacramento, CA, USA
| | - Veronica Martinez-Cerdeno
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA; Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California, Sacramento, CA, USA; Department of Pathology and Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
| | - Randi Hagerman
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, USA; Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA.
| |
Collapse
|
16
|
Biag HMB, Potter LA, Wilkins V, Afzal S, Rosvall A, Salcedo-Arellano MJ, Rajaratnam A, Manzano-Nunez R, Schneider A, Tassone F, Rivera SM, Hagerman RJ. Metformin treatment in young children with fragile X syndrome. Mol Genet Genomic Med 2019; 7:e956. [PMID: 31520524 PMCID: PMC6825840 DOI: 10.1002/mgg3.956] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 08/07/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Metformin is a drug commonly used in individuals with type 2 diabetes, obesity, and impaired glucose tolerance. It has a strong safety profile in both children and adults. Studies utilizing the Drosophila model and knock out mouse model of fragile X syndrome (FXS) have found metformin to rescue memory, social novelty deficits, and neuroanatomical abnormalities. These studies provided preliminary evidence that metformin could be used as a targeted treatment for the cognitive and behavioral problems associated with FXS. Previously, a case series of children and adults with FXS treated with metformin demonstrated improvements in irritability, social responsiveness, language, and hyperactivity. METHODS Here, we present nine children with FXS between 2 and 7 years of age who were treated clinically with metformin and monitored for behavioral and metabolic changes. RESULTS Parent reports and developmental testing before and after metformin are presented. There were improvements in language development and behavior (such as lethargy and stereotypy) in most of the patients. CONCLUSION These results support the need for a controlled trial of metformin in children with FXS under 7 years old whose brains are in a critical developmental window and thus may experience a greater degree of clinical benefit from metformin.
Collapse
Affiliation(s)
- Hazel Maridith B Biag
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - Laura A Potter
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - Victoria Wilkins
- Department of Pediatric Inpatient Medicine, University of Utah and Primary Children's Hospital, Salt Lake City, Utah
| | - Sumra Afzal
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - Alexis Rosvall
- University of California Davis School of Medicine, Sacramento, California
| | - Maria Jimena Salcedo-Arellano
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - Akash Rajaratnam
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Case Western Reserve University School of Medicine, Cleveland, Ohio
| | | | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Biochemistry and Molecular Medicine, University of California Davis Medical Center, Sacramento, California
| | - Susan M Rivera
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Psychology, University of California Davis, Davis, California.,Neurocognitive Development Lab, Center for Mind and Brain, Davis, California
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| |
Collapse
|
17
|
Babbs RK, Beierle JA, Ruan QT, Kelliher JC, Chen MM, Feng AX, Kirkpatrick SL, Benitez FA, Rodriguez FA, Pierre JJ, Anandakumar J, Kumar V, Mulligan MK, Bryant CD. Cyfip1 Haploinsufficiency Increases Compulsive-Like Behavior and Modulates Palatable Food Intake in Mice: Dependence on Cyfip2 Genetic Background, Parent-of Origin, and Sex. G3 (BETHESDA, MD.) 2019; 9:3009-3022. [PMID: 31324746 PMCID: PMC6723122 DOI: 10.1534/g3.119.400470] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/18/2019] [Indexed: 12/11/2022]
Abstract
Binge eating (BE) is a heritable trait associated with eating disorders and involves episodes of rapid, large amounts of food consumption. We previously identified cytoplasmic FMR1-interacting protein 2 (Cyfip2) as a genetic factor underlying compulsive-like BE in mice. CYFIP2 is a homolog of CYFIP1 which is one of four paternally-deleted genes in patients with Type I Prader-Willi Syndrome (PWS), a neurodevelopmental disorder whereby 70% of cases involve paternal 15q11-q13 deletion. PWS symptoms include hyperphagia, obesity (if untreated), cognitive deficits, and obsessive-compulsive behaviors. We tested whether Cyfip1 haploinsufficiency (+/-) would enhance compulsive-like behavior and palatable food (PF) intake in a parental origin- and sex-dependent manner on two Cyfip2 genetic backgrounds, including the BE-prone C57BL/6N (Cyfip2N/N) background and the BE-resistant C57BL/6J (Cyfip2J/J) background. Cyfip1+/- mice showed increased compulsive-like behavior on both backgrounds and increased PF intake on the Cyfip2N/N background. In contrast, maternal Cyfip1 haploinsufficiency on the BE-resistant Cyfip2J/J background induced a robust escalation in PF intake in wild-type Cyfip1J/J males while having no effect in Cyfip1J/- males. Notably, induction of behavioral phenotypes in wild-type males following maternal Fmr1+/- has previously been reported. In the hypothalamus, there was a paternally-enhanced reduction in CYFIP1 protein whereas in the nucleus accumbens, there was a maternally-enhanced reduction in CYFIP1 protein. Nochange in FMR1 protein (FMRP) was observed in Cyfip1+/- mice, regardless of parental origin. To summarize, Cyfip1 haploinsufficiency increased compulsive-like behavior and induced genetic background-dependent, sex-dependent, and parent-of-origin-dependent effects on PF consumption and CYFIP1 expression that could have relevance for neurodevelopmental and neuropsychiatric disorders.
Collapse
Affiliation(s)
- Richard K Babbs
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Jacob A Beierle
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
- T32 NIGMS Training Program in Biomolecular Pharmacology
- Boston University's Transformative Training Program in Addiction Science (TTPAS), Biomedical Genetics, Boston University School of Medicine, Boston, MA 02118
| | - Qiu T Ruan
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
- T32 NIGMS Training Program in Biomolecular Pharmacology
- Boston University's Transformative Training Program in Addiction Science (TTPAS), Biomedical Genetics, Boston University School of Medicine, Boston, MA 02118
| | - Julia C Kelliher
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Melanie M Chen
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Ashley X Feng
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Stacey L Kirkpatrick
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Fabiola A Benitez
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Fred A Rodriguez
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Johanne J Pierre
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Jeya Anandakumar
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| | - Vivek Kumar
- The Jackson Laboratory, 600 Main St., Bar Harbor, ME 04609, and
| | - Megan K Mulligan
- Department of Genetics, Genomics, and Informatics, University of Tennessee Health Science Center, 71 S. Manassas St, Memphis, TN 38163
| | - Camron D Bryant
- Laboratory of Addiction Genetics, Department of Pharmacology and Experimental Therapeutics and Psychiatry
| |
Collapse
|
18
|
Leboucher A, Pisani DF, Martinez-Gili L, Chilloux J, Bermudez-Martin P, Van Dijck A, Ganief T, Macek B, Becker JAJ, Le Merrer J, Kooy RF, Amri EZ, Khandjian EW, Dumas ME, Davidovic L. The translational regulator FMRP controls lipid and glucose metabolism in mice and humans. Mol Metab 2019; 21:22-35. [PMID: 30686771 PMCID: PMC6407369 DOI: 10.1016/j.molmet.2019.01.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 01/02/2019] [Accepted: 01/08/2019] [Indexed: 01/09/2023] Open
Abstract
Objectives The Fragile X Mental Retardation Protein (FMRP) is a widely expressed RNA-binding protein involved in translation regulation. Since the absence of FMRP leads to Fragile X Syndrome (FXS) and autism, FMRP has been extensively studied in brain. The functions of FMRP in peripheral organs and on metabolic homeostasis remain elusive; therefore, we sought to investigate the systemic consequences of its absence. Methods Using metabolomics, in vivo metabolic phenotyping of the Fmr1-KO FXS mouse model and in vitro approaches, we show that the absence of FMRP induced a metabolic shift towards enhanced glucose tolerance and insulin sensitivity, reduced adiposity, and increased β-adrenergic-driven lipolysis and lipid utilization. Results Combining proteomics and cellular assays, we highlight that FMRP loss increased hepatic protein synthesis and impacted pathways notably linked to lipid metabolism. Mapping metabolomic and proteomic phenotypes onto a signaling and metabolic network, we predicted that the coordinated metabolic response to FMRP loss was mediated by dysregulation in the abundances of specific hepatic proteins. We experimentally validated these predictions, demonstrating that the translational regulator FMRP associates with a subset of mRNAs involved in lipid metabolism. Finally, we highlight that FXS patients mirror metabolic variations observed in Fmr1-KO mice with reduced circulating glucose and insulin and increased free fatty acids. Conclusions Loss of FMRP results in a widespread coordinated systemic response that notably involves upregulation of protein translation in the liver, increased utilization of lipids, and significant changes in metabolic homeostasis. Our study unravels metabolic phenotypes in FXS and further supports the importance of translational regulation in the homeostatic control of systemic metabolism. Loss of the translational regulator FMRP impacts glucose and lipid homeostasis in mouse and human. FMR1-deficiency modifies blood metabolic markers. Loss of FMRP enhances the insulin response and lipolysis. Loss of FMRP exaggerates hepatic protein synthesis. FMRP controls the translation of key hepatic proteins involved in lipid metabolism.
Collapse
Affiliation(s)
- Antoine Leboucher
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Didier F Pisani
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France
| | - Laura Martinez-Gili
- Division of Integrative Systems Medicine and Digestive Diseases, Department of Surgery and Cancer, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, United Kingdom
| | - Julien Chilloux
- Division of Integrative Systems Medicine and Digestive Diseases, Department of Surgery and Cancer, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, United Kingdom
| | - Patricia Bermudez-Martin
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
| | - Anke Van Dijck
- Department of Medical Genetics, University and University Hospital of Antwerp, Prins Boudewijnlaan 43/6, 2650 Edegem, Belgium
| | | | | | - Jérôme A J Becker
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Inserm, Université François Rabelais, IFCE, 37380, Nouzilly, France
| | - Julie Le Merrer
- Physiologie de la Reproduction et des Comportements, INRA UMR-0085, CNRS UMR-7247, Inserm, Université François Rabelais, IFCE, 37380, Nouzilly, France
| | - R Frank Kooy
- Department of Medical Genetics, University and University Hospital of Antwerp, Prins Boudewijnlaan 43/6, 2650 Edegem, Belgium
| | - Ez-Zoubir Amri
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France
| | - Edouard W Khandjian
- Centre de Recherche CERVO, Institut en Santé Mentale de Québec, PQ, Canada; Département de Psychiatrie et des Neurosciences, Faculté de Médecine, Université Laval, Québec, PQ, Canada
| | - Marc-Emmanuel Dumas
- Division of Integrative Systems Medicine and Digestive Diseases, Department of Surgery and Cancer, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, United Kingdom
| | - Laetitia Davidovic
- Université Côte d'Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France.
| |
Collapse
|
19
|
Weisz ED, Towheed A, Monyak RE, Toth MS, Wallace DC, Jongens TA. Loss of Drosophila FMRP leads to alterations in energy metabolism and mitochondrial function. Hum Mol Genet 2019; 27:95-106. [PMID: 29106525 PMCID: PMC5886180 DOI: 10.1093/hmg/ddx387] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 10/25/2017] [Indexed: 11/28/2022] Open
Abstract
Fragile X Syndrome (FXS), the most prevalent form of inherited intellectual disability and the foremost monogenetic cause of autism, is caused by loss of expression of the FMR1 gene . Here, we show that dfmr1 modulates the global metabolome in Drosophila. Despite our previous discovery of increased brain insulin signaling, our results indicate that dfmr1 mutants have reduced carbohydrate and lipid stores and are hypersensitive to starvation stress. The observed metabolic deficits cannot be explained by feeding behavior, as we report that dfmr1 mutants are hyperphagic. Rather, our data identify dfmr1 as a regulator of mitochondrial function. We demonstrate that under supersaturating conditions, dfmr1 mutant mitochondria have significantly increased maximum electron transport system (ETS) capacity. Moreover, electron micrographs of indirect flight muscle reveal striking morphological changes in the dfmr1 mutant mitochondria. Taken together, our results illustrate the importance of dfmr1 for proper maintenance of nutrient homeostasis and mitochondrial function.
Collapse
Affiliation(s)
- Eliana D Weisz
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Atif Towheed
- Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Rachel E Monyak
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Meridith S Toth
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Douglas C Wallace
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.,Center for Mitochondrial and Epigenomic Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.,Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Thomas A Jongens
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| |
Collapse
|
20
|
Leboucher A, Bermudez-Martin P, Mouska X, Amri EZ, Pisani DF, Davidovic L. Fmr1-Deficiency Impacts Body Composition, Skeleton, and Bone Microstructure in a Mouse Model of Fragile X Syndrome. Front Endocrinol (Lausanne) 2019; 10:678. [PMID: 31632352 PMCID: PMC6783488 DOI: 10.3389/fendo.2019.00678] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 09/18/2019] [Indexed: 11/13/2022] Open
Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder associated with intellectual disability, hyperactivity, and autism. FXS is due to the silencing of the X-linked FMR1 gene. Murine models of FXS, knock-out (KO) for the murine homolog Fmr1, have been generated, exhibiting CNS-related behavioral, and neuronal anomalies reminiscent of the human phenotypes. As a reflection of the almost ubiquitous expression of the FMR1 gene, FXS is also accompanied by physical abnormalities. This suggests that the FMR1-deficiency could impact skeletal ontogenesis. In the present study, we highlight that Fmr1-KO mice display changes in body composition with an increase in body weight, likely due to both increase of skeleton length and muscular mass along with reduced visceral adiposity. We also show that, while Fmr1-deficiency has no overt impact on cortical bone mineral density (BMD), cortical thickness was increased, and cortical eccentricity was decreased in the femurs from Fmr1-KO mice as compared to controls. Also, trabecular pore volume was reduced and trabecular thickness distribution was shifted toward higher ranges in Fmr1-KO femurs. Finally, we show that Fmr1-KO mice display increased physical activity. Although the precise molecular signaling mechanism that produces these skeletal and bone microstructure changes remains to be determined, our study warrants further investigation on the impact of FMR1-deficiency on whole-body composition, as well as skeletal and bone architecture.
Collapse
Affiliation(s)
| | | | - Xavier Mouska
- Université Côte d'Azur, CNRS, IPMC, Valbonne, France
| | | | | | - Laetitia Davidovic
- Université Côte d'Azur, CNRS, IPMC, Valbonne, France
- *Correspondence: Laetitia Davidovic
| |
Collapse
|
21
|
Luhur A, Buddika K, Ariyapala IS, Chen S, Sokol NS. Opposing Post-transcriptional Control of InR by FMRP and LIN-28 Adjusts Stem Cell-Based Tissue Growth. Cell Rep 2018; 21:2671-2677. [PMID: 29212015 DOI: 10.1016/j.celrep.2017.11.039] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 10/13/2017] [Accepted: 11/10/2017] [Indexed: 01/01/2023] Open
Abstract
Although the intrinsic mechanisms that control whether stem cells divide symmetrically or asymmetrically underlie tissue growth and homeostasis, they remain poorly defined. We report that the RNA-binding protein fragile X mental retardation protein (FMRP) limits the symmetric division, and resulting expansion, of the stem cell population during adaptive intestinal growth in Drosophila. The elevated insulin sensitivity that FMRP-deficient progenitor cells display contributes to their accelerated expansion, which is suppressed by the depletion of insulin-signaling components. This FMRP activity is mediated solely via a second conserved RNA-binding protein, LIN-28, known to boost insulin signaling in stem cells. Via LIN-28, FMRP controls progenitor cell behavior by post-transcriptionally repressing the level of insulin receptor (InR). This study identifies the stem cell-based mechanism by which FMRP controls tissue adaptation, and it raises the possibility that defective adaptive growth underlies the accelerated growth, gastrointestinal, and other symptoms that affect fragile X syndrome patients.
Collapse
Affiliation(s)
- Arthur Luhur
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | - Kasun Buddika
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | | | - Shengyao Chen
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
| | | |
Collapse
|
22
|
Drozd M, Bardoni B, Capovilla M. Modeling Fragile X Syndrome in Drosophila. Front Mol Neurosci 2018; 11:124. [PMID: 29713264 PMCID: PMC5911982 DOI: 10.3389/fnmol.2018.00124] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/29/2018] [Indexed: 01/18/2023] Open
Abstract
Intellectual disability (ID) and autism are hallmarks of Fragile X Syndrome (FXS), a hereditary neurodevelopmental disorder. The gene responsible for FXS is Fragile X Mental Retardation gene 1 (FMR1) encoding the Fragile X Mental Retardation Protein (FMRP), an RNA-binding protein involved in RNA metabolism and modulating the expression level of many targets. Most cases of FXS are caused by silencing of FMR1 due to CGG expansions in the 5'-UTR of the gene. Humans also carry the FXR1 and FXR2 paralogs of FMR1 while flies have only one FMR1 gene, here called dFMR1, sharing the same level of sequence homology with all three human genes, but functionally most similar to FMR1. This enables a much easier approach for FMR1 genetic studies. Drosophila has been widely used to investigate FMR1 functions at genetic, cellular, and molecular levels since dFMR1 mutants have many phenotypes in common with the wide spectrum of FMR1 functions that underlay the disease. In this review, we present very recent Drosophila studies investigating FMRP functions at genetic, cellular, molecular, and electrophysiological levels in addition to research on pharmacological treatments in the fly model. These studies have the potential to aid the discovery of pharmacological therapies for FXS.
Collapse
Affiliation(s)
- Małgorzata Drozd
- Université Côte d'Azur, CNRS, IPMC, Valbonne, France.,CNRS LIA (Neogenex), Valbonne, France
| | - Barbara Bardoni
- CNRS LIA (Neogenex), Valbonne, France.,Université Côte d'Azur, INSERM, CNRS, IPMC, Valbonne, France
| | - Maria Capovilla
- Université Côte d'Azur, CNRS, IPMC, Valbonne, France.,CNRS LIA (Neogenex), Valbonne, France
| |
Collapse
|
23
|
Gilbert J, Man HY. Fundamental Elements in Autism: From Neurogenesis and Neurite Growth to Synaptic Plasticity. Front Cell Neurosci 2017; 11:359. [PMID: 29209173 PMCID: PMC5701944 DOI: 10.3389/fncel.2017.00359] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/31/2017] [Indexed: 01/12/2023] Open
Abstract
Autism spectrum disorder (ASD) is a set of neurodevelopmental disorders with a high prevalence and impact on society. ASDs are characterized by deficits in both social behavior and cognitive function. There is a strong genetic basis underlying ASDs that is highly heterogeneous; however, multiple studies have highlighted the involvement of key processes, including neurogenesis, neurite growth, synaptogenesis and synaptic plasticity in the pathophysiology of neurodevelopmental disorders. In this review article, we focus on the major genes and signaling pathways implicated in ASD and discuss the cellular, molecular and functional studies that have shed light on common dysregulated pathways using in vitro, in vivo and human evidence. HighlightsAutism spectrum disorder (ASD) has a prevalence of 1 in 68 children in the United States. ASDs are highly heterogeneous in their genetic basis. ASDs share common features at the cellular and molecular levels in the brain. Most ASD genes are implicated in neurogenesis, structural maturation, synaptogenesis and function.
Collapse
Affiliation(s)
- James Gilbert
- Department of Biology, Boston University, Boston, MA, United States
| | - Heng-Ye Man
- Department of Biology, Boston University, Boston, MA, United States.,Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, United States
| |
Collapse
|
24
|
Abstract
Fragile X syndrome (FXS) is the leading inherited form of intellectual disability and autism spectrum disorder, and patients can present with severe behavioural alterations, including hyperactivity, impulsivity and anxiety, in addition to poor language development and seizures. FXS is a trinucleotide repeat disorder, in which >200 repeats of the CGG motif in FMR1 leads to silencing of the gene and the consequent loss of its product, fragile X mental retardation 1 protein (FMRP). FMRP has a central role in gene expression and regulates the translation of potentially hundreds of mRNAs, many of which are involved in the development and maintenance of neuronal synaptic connections. Indeed, disturbances in neuroplasticity is a key finding in FXS animal models, and an imbalance in inhibitory and excitatory neuronal circuits is believed to underlie many of the clinical manifestations of this disorder. Our knowledge of the proteins that are regulated by FMRP is rapidly growing, and this has led to the identification of multiple targets for therapeutic intervention, some of which have already moved into clinical trials or clinical practice.
Collapse
|
25
|
Dy ABC, Tassone F, Eldeeb M, Salcedo-Arellano MJ, Tartaglia N, Hagerman R. Metformin as targeted treatment in fragile X syndrome. Clin Genet 2017; 93:216-222. [PMID: 28436599 DOI: 10.1111/cge.13039] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/18/2017] [Accepted: 04/20/2017] [Indexed: 12/23/2022]
Abstract
BACKGROUND Individuals with fragile X syndrome (FXS) have both behavioral and medical comorbidities and the latter include obesity in approximately 30% and the Prader-Willi Phenotype (PWP) characterized by severe hyperphagia and morbid obesity in less than 10%. Metformin is a drug used in individuals with type 2 diabetes, obesity or impaired glucose tolerance and it has a strong safety profile in children and adults. Recently published studies in the Drosophila model and the knock out mouse model of FXS treated with metformin demonstrate the rescue of multiple phenotypes of FXS. MATERIALS AND METHODS We present 7 cases of individuals with FXS who have been treated with metformin clinically. One case with type 2 diabetes, 3 cases with the PWP, 2 adults with obesity and/or behavioral problems and, a young child with FXS. These individuals were clinically treated with metformin and monitored for behavioral changes with the Aberrant Behavior Checklist and metabolic changes with a fasting glucose and HgbA1c. RESULTS We found consistent improvements in irritability, social responsiveness, hyperactivity, and social avoidance, in addition to comments from the family regarding improvements in language and conversational skills. No significant side-effects were noted and most patients with obesity lost weight. CONCLUSION We recommend a controlled trial of metformin in those with FXS. Metformin appears to be an effective treatment of obesity including those with the PWP in FXS. Our study suggests that metformin may also be a targeted treatment for improving behavior and language in children and adults with FXS.
Collapse
Affiliation(s)
- A B C Dy
- Ateneo de Manila University School of Medicine and Public Health, Pasig City, Philippines.,MedMom Institute for Human Development, Pasig City, Philippines.,Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, California
| | - F Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, California.,Department of Biochemistry and Molecular Medicine, University of California Davis Medical Center, Sacramento, California
| | - M Eldeeb
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - M J Salcedo-Arellano
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| | - N Tartaglia
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado
| | - R Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, California.,Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
| |
Collapse
|
26
|
Monyak RE, Emerson D, Schoenfeld BP, Zheng X, Chambers DB, Rosenfelt C, Langer S, Hinchey P, Choi CH, McDonald TV, Bolduc FV, Sehgal A, McBride SM, Jongens TA. Insulin signaling misregulation underlies circadian and cognitive deficits in a Drosophila fragile X model. Mol Psychiatry 2017; 22:1140-1148. [PMID: 27090306 PMCID: PMC5071102 DOI: 10.1038/mp.2016.51] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 03/01/2016] [Indexed: 12/22/2022]
Abstract
Fragile X syndrome (FXS) is an undertreated neurodevelopmental disorder characterized by low intelligence quotent and a wide range of other symptoms including disordered sleep and autism. Although FXS is the most prevalent inherited cause of intellectual disability, its mechanistic underpinnings are not well understood. Using Drosophila as a model of FXS, we showed that select expression of dfmr1 in the insulin-producing cells (IPCs) of the brain was sufficient to restore normal circadian behavior and to rescue the memory deficits in the fragile X mutant fly. Examination of the insulin signaling (IS) pathway revealed elevated levels of Drosophila insulin-like peptide 2 (Dilp2) in the IPCs and elevated IS in the dfmr1 mutant brain. Consistent with a causal role for elevated IS in dfmr1 mutant phenotypes, the expression of dfmr1 specifically in the IPCs reduced IS, and genetic reduction of the insulin pathway also led to amelioration of circadian and memory defects. Furthermore, we showed that treatment with the FDA-approved drug metformin also rescued memory. Finally, we showed that reduction of IS is required at different time points to rescue circadian behavior and memory. Our results indicate that insulin misregulation underlies the circadian and cognitive phenotypes displayed by the Drosophila fragile X model, and thus reveal a metabolic pathway that can be targeted by new and already approved drugs to treat fragile X patients.
Collapse
Affiliation(s)
- Rachel E. Monyak
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158
| | - Danielle Emerson
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158
| | - Brian P. Schoenfeld
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158,Section of Molecular Cardiology, Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Xiangzhong Zheng
- Department of Neuroscience and Howard Hughes Medical Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158
| | - Daniel B. Chambers
- Department of Pediatric Neurology, Center for Neuroscience, University of Alberta, Edmonton, Canada AB T6G 2H7
| | - Cory Rosenfelt
- Department of Pediatric Neurology, Center for Neuroscience, University of Alberta, Edmonton, Canada AB T6G 2H7
| | - Steven Langer
- Department of Pediatric Neurology, Center for Neuroscience, University of Alberta, Edmonton, Canada AB T6G 2H7
| | - Paul Hinchey
- Section of Molecular Cardiology, Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Catherine H. Choi
- Section of Molecular Cardiology, Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461,Department of Dermatology, Drexel University College of Medicine, 219 N. Broad Street, Philadelphia, PA, 19107
| | - Thomas V. McDonald
- Section of Molecular Cardiology, Departments of Medicine and Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Francois V. Bolduc
- Department of Pediatric Neurology, Center for Neuroscience, University of Alberta, Edmonton, Canada AB T6G 2H7
| | - Amita Sehgal
- Department of Neuroscience and Howard Hughes Medical Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158
| | - Sean M.J. McBride
- Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158,To whom correspondence should be addressed: and , phone: 215-573-9332, fax: 215-573-9411
| | - Thomas A. Jongens
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104-5158,To whom correspondence should be addressed: and , phone: 215-573-9332, fax: 215-573-9411
| |
Collapse
|
27
|
Abstract
OBJECTIVES The purpose of this systematic literature review is to describe what is known about fragile X syndrome (FXS) and to identify research gaps. The results can be used to help inform future public health research and provide pediatricians with up-to-date information about the implications of the condition for individuals and their families. METHODS An electronic literature search was conducted, guided by a variety of key words. The search focused on 4 areas of both clinical and public health importance: (1) the full mutation phenotype, (2) developmental trajectories across the life span, (3) available interventions and treatments, and (4) impact on the family. A total of 661 articles were examined and 203 were included in the review. RESULTS The information is presented in the following categories: developmental profile (cognition, language, functional skills, and transition to adulthood), social-emotional profile (cooccurring psychiatric conditions and behavior problems), medical profile (physical features, seizures, sleep, health problems, and physiologic features), treatment and interventions (educational/behavioral, allied health services, and pharmacologic), and impact on the family (family environment and financial impact). Research gaps also are presented. CONCLUSIONS The identification and treatment of FXS remains an important public health and clinical concern. The information presented in this article provides a more robust understanding of FXS and the impact of this complex condition for pediatricians. Despite a wealth of information about the condition, much work remains to fully support affected individuals and their families.
Collapse
Affiliation(s)
- Melissa Raspa
- RTI International, Research Triangle Park, North Carolina; and
| | - Anne C Wheeler
- RTI International, Research Triangle Park, North Carolina; and
| | - Catharine Riley
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
| |
Collapse
|
28
|
Pugin A, Faundes V, Santa María L, Curotto B, Aliaga S, Salas I, Soto P, Bravo P, Peña M, Alliende M. Clinical, molecular, and pharmacological aspects of FMR1 -related disorders. NEUROLOGÍA (ENGLISH EDITION) 2017. [DOI: 10.1016/j.nrleng.2014.10.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
|
29
|
Martínez-Cerdeño V. Dendrite and spine modifications in autism and related neurodevelopmental disorders in patients and animal models. Dev Neurobiol 2017; 77:393-404. [PMID: 27390186 PMCID: PMC5219951 DOI: 10.1002/dneu.22417] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/29/2016] [Accepted: 07/04/2016] [Indexed: 12/12/2022]
Abstract
Dendrites and spines are the main neuronal structures receiving input from other neurons and glial cells. Dendritic and spine number, size, and morphology are some of the crucial factors determining how signals coming from individual synapses are integrated. Much remains to be understood about the characteristics of neuronal dendrites and dendritic spines in autism and related disorders. Although there have been many studies conducted using autism mouse models, few have been carried out using postmortem human tissue from patients. Available animal models of autism include those generated through genetic modifications and those non-genetic models of the disease. Here, we review how dendrite and spine morphology and number is affected in autism and related neurodevelopmental diseases, both in human, and genetic and non-genetic animal models of autism. Overall, data obtained from human and animal models point to a generalized reduction in the size and number, as well as an alteration of the morphology of dendrites; and an increase in spine densities with immature morphology, indicating a general spine immaturity state in autism. Additional human studies on dendrite and spine number and morphology in postmortem tissue are needed to understand the properties of these structures in the cerebral cortex of patients with autism. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 419-437, 2017.
Collapse
Affiliation(s)
- Verónica Martínez-Cerdeño
- Department of Pathology and Laboratory Medicine, UC Davis, Sacramento, California
- Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California, North California, Sacramento, California
- MIND Institute, UC Davis School of Medicine, Sacramento, California
| |
Collapse
|
30
|
Martínez-Cerdeño V, Lechpammer M, Noctor S, Ariza J, Hagerman P, Hagerman R. FMR1 premutation with Prader-Willi phenotype and fragile X-associated tremor/ataxia syndrome. Clin Case Rep 2017; 5:625-629. [PMID: 28469864 PMCID: PMC5412812 DOI: 10.1002/ccr3.834] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 11/07/2016] [Accepted: 01/04/2017] [Indexed: 11/12/2022] Open
Abstract
This is a report of FMR1 premutation with Prader-Willi phenotype (PWP) and FXTAS. Although the PWP is common in fragile X syndrome (FXS), it has never been described in someone with the premutation. The patient presented intranuclear inclusions, severe obesity, hyperphagia, and ADHD symptoms, typical of the PWP in FXS. In addition, the autopsy revealed multiple architectural cortical abnormalities.
Collapse
Affiliation(s)
- Verónica Martínez-Cerdeño
- Department of Pathology and Laboratory Medicine UC Davis Medical Center Sacramento CA USA.,Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California Sacramento CA USA.,MIND Institute UC Davis Medical Center Sacramento CA USA
| | - Mirna Lechpammer
- Department of Pathology and Laboratory Medicine UC Davis Medical Center Sacramento CA USA
| | - Stephen Noctor
- MIND Institute UC Davis Medical Center Sacramento CA USA.,Department of Psychiatry and Behavioral Sciences UC Davis Medical Center Sacramento CA USA
| | - Jeanelle Ariza
- Department of Pathology and Laboratory Medicine UC Davis Medical Center Sacramento CA USA.,Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California Sacramento CA USA
| | - Paul Hagerman
- Department of Biochemistry and Molecular Medicine UC Davis Medical Center Sacramento CA USA
| | - Randi Hagerman
- MIND Institute UC Davis Medical Center Sacramento CA USA.,Department of Pediatrics UC Davis Medical Center Sacramento CA USA
| |
Collapse
|
31
|
Muzar Z, Lozano R, Kolevzon A, Hagerman RJ. The neurobiology of the Prader-Willi phenotype of fragile X syndrome. Intractable Rare Dis Res 2016; 5:255-261. [PMID: 27904820 PMCID: PMC5116860 DOI: 10.5582/irdr.2016.01082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability and autism, caused by a CGG expansion to greater than 200 repeats in the promoter region of FMR1 on the bottom of the X chromosome. A subgroup of individuals with FXS experience hyperphagia, lack of satiation after meals and severe obesity, this subgroup is referred to have the Prader-Willi phenotype of FXS. Prader-Willi syndrome is one of the most common genetic severe obesity disorders known and it is caused by the lack of the paternal 15q11-13 region. Affected individuals suffer from hyperphagia, lack of satiation, intellectual disability, and behavioral problems. Children with fragile X syndrome Prader-Willi phenotye and those with Prader Willi syndrome have clinical and molecular similarities reviewed here which will impact new treatment options for both disorders.
Collapse
Affiliation(s)
- Zukhrofi Muzar
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, b)Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
- Department of Histology, Universitas Muhammadiyah Sumatera Utara (UMSU) Faculty of Medicine, Medan, North Sumatera, Indonesia
| | - Reymundo Lozano
- Seaver Autism Center for Research and Treatment, d)Departments of Genetics and Genomic Sciences, e)Psychiatry, and f)Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Address correspondence to: Dr. Reymundo Lozano, Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1230, New York, NY 10025, USA. E-mail: Dr. Randi J. Hagerman, MIND Institute, UC Davis Health System, 2825 50th Street, Sacramento, CA 95817, USA. E-mail:
| | - Alexander Kolevzon
- Seaver Autism Center for Research and Treatment, d)Departments of Genetics and Genomic Sciences, e)Psychiatry, and f)Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Randi J. Hagerman
- Seaver Autism Center for Research and Treatment, d)Departments of Genetics and Genomic Sciences, e)Psychiatry, and f)Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Address correspondence to: Dr. Reymundo Lozano, Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1230, New York, NY 10025, USA. E-mail: Dr. Randi J. Hagerman, MIND Institute, UC Davis Health System, 2825 50th Street, Sacramento, CA 95817, USA. E-mail:
| |
Collapse
|
32
|
Cheon CK. Genetics of Prader-Willi syndrome and Prader-Will-Like syndrome. Ann Pediatr Endocrinol Metab 2016; 21:126-135. [PMID: 27777904 PMCID: PMC5073158 DOI: 10.6065/apem.2016.21.3.126] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 11/29/2022] Open
Abstract
The Prader-Willi syndrome (PWS) is a human imprinting disorder resulting from genomic alterations that inactivate imprinted, paternally expressed genes in human chromosome region 15q11-q13. This genetic condition appears to be a contiguous gene syndrome caused by the loss of at least 2 of a number of genes expressed exclusively from the paternal allele, including SNRPN, MKRN3, MAGEL2, NDN and several snoRNAs, but it is not yet well known which specific genes in this region are associated with this syndrome. Prader-Will-Like syndrome (PWLS) share features of the PWS phenotype and the gene functions disrupted in PWLS are likely to lie in genetic pathways that are important for the development of PWS phenotype. However, the genetic basis of these rare disorders differs and the absence of a correct diagnosis may worsen the prognosis of these individuals due to the endocrine-metabolic malfunctioning associated with the PWS. Therefore, clinicians face a challenge in determining when to request the specific molecular test used to identify patients with classical PWS because the signs and symptoms of PWS are common to other syndromes such as PWLS. This review aims to provide an overview of current knowledge relating to the genetics of PWS and PWLS, with an emphasis on identification of patients that may benefit from further investigation and genetic screening.
Collapse
Affiliation(s)
- Chong Kun Cheon
- Division of Pediatric Endocrinology and Metabolism, Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, Korea
| |
Collapse
|
33
|
Lozano R, Azarang A, Wilaisakditipakorn T, Hagerman RJ. Fragile X syndrome: A review of clinical management. Intractable Rare Dis Res 2016; 5:145-57. [PMID: 27672537 PMCID: PMC4995426 DOI: 10.5582/irdr.2016.01048] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The fragile X mental retardation 1 gene, which codes for the fragile X mental retardation 1 protein, usually has 5 to 40 CGG repeats in the 5' untranslated promoter. The full mutation is the almost always the cause of fragile X syndrome (FXS). The prevalence of FXS is about 1 in 4,000 to 1 in 7,000 in the general population although the prevalence varies in different regions of the world. FXS is the most common inherited cause of intellectual disability and autism. The understanding of the neurobiology of FXS has led to many targeted treatments, but none have cured this disorder. The treatment of the medical problems and associated behaviors remain the most useful intervention for children with FXS. In this review, we focus on the non-pharmacological and pharmacological management of medical and behavioral problems associated with FXS as well as current recommendations for follow-up and surveillance.
Collapse
Affiliation(s)
- Reymundo Lozano
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, UC Davis, CA, USA
- Department of Pediatrics, UC Davis, Sacramento, CA, USA
- Address correspondence to: Dr. Reymundo Lozano, Medical Investigation of Neurodevelopmental Disorders MIND Institute, UC Davis, CA, USA; Department of Pediatrics, UC Davis, Sacramento, CA, USA. E-mail:
| | - Atoosa Azarang
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, UC Davis, CA, USA
- Department of Pediatrics, UC Davis, Sacramento, CA, USA
| | - Tanaporn Wilaisakditipakorn
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, UC Davis, CA, USA
- Department of Pediatrics, UC Davis, Sacramento, CA, USA
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, UC Davis, CA, USA
- Department of Pediatrics, UC Davis, Sacramento, CA, USA
| |
Collapse
|
34
|
Butler MG. Single Gene and Syndromic Causes of Obesity: Illustrative Examples. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 140:1-45. [PMID: 27288824 DOI: 10.1016/bs.pmbts.2015.12.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Obesity is a significant health problem in westernized societies, particularly in the United States where it has reached epidemic proportions in both adults and children. The prevalence of childhood obesity has doubled in the past 30 years. The causation is complex with multiple sources, including an obesity promoting environment with plentiful highly dense food sources and overall decreased physical activity noted for much of the general population, but genetic factors clearly play a role. Advances in genetic technology using candidate gene approaches, genome-wide association studies, structural and expression microarrays, and next generation sequencing have led to the discovery of hundreds of genes recognized as contributing to obesity. Polygenic and monogenic causes of obesity are now recognized including dozens of examples of syndromic obesity with Prader-Willi syndrome, as a classical example and recognized as the most common known cause of life-threatening obesity. Genetic factors playing a role in the causation of obesity will be discussed along with the growing evidence of single genes and the continuum between monogenic and polygenic obesity. The clinical and genetic aspects of four classical but rare obesity-related syndromes (ie, Prader-Willi, Alström, fragile X, and Albright hereditary osteodystrophy) will be described and illustrated in this review of single gene and syndromic causes of obesity.
Collapse
Affiliation(s)
- Merlin G Butler
- Departments of Psychiatry & Behavioral Sciences and Pediatrics, University of Kansas Medical Center, Kansas City, KS, United States of America.
| |
Collapse
|
35
|
Subramanian M, Timmerman CK, Schwartz JL, Pham DL, Meffert MK. Characterizing autism spectrum disorders by key biochemical pathways. Front Neurosci 2015; 9:313. [PMID: 26483618 PMCID: PMC4586332 DOI: 10.3389/fnins.2015.00313] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 08/20/2015] [Indexed: 12/29/2022] Open
Abstract
The genetic and phenotypic heterogeneity of autism spectrum disorders (ASD) presents a substantial challenge for diagnosis, classification, research, and treatment. Investigations into the underlying molecular etiology of ASD have often yielded mixed and at times opposing findings. Defining the molecular and biochemical underpinnings of heterogeneity in ASD is crucial to our understanding of the pathophysiological development of the disorder, and has the potential to assist in diagnosis and the rational design of clinical trials. In this review, we propose that genetically diverse forms of ASD may be usefully parsed into entities resulting from converse patterns of growth regulation at the molecular level, which lead to the correlates of general synaptic and neural overgrowth or undergrowth. Abnormal brain growth during development is a characteristic feature that has been observed both in children with autism and in mouse models of autism. We review evidence from syndromic and non-syndromic ASD to suggest that entities currently classified as autism may fundamentally differ by underlying pro- or anti-growth abnormalities in key biochemical pathways, giving rise to either excessive or reduced synaptic connectivity in affected brain regions. We posit that this classification strategy has the potential not only to aid research efforts, but also to ultimately facilitate early diagnosis and direct appropriate therapeutic interventions.
Collapse
Affiliation(s)
- Megha Subramanian
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Christina K Timmerman
- Department of Biological Chemistry, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Joshua L Schwartz
- Department of Biological Chemistry, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Daniel L Pham
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine Baltimore, MD, USA
| | - Mollie K Meffert
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine Baltimore, MD, USA ; Department of Biological Chemistry, Johns Hopkins University School of Medicine Baltimore, MD, USA
| |
Collapse
|
36
|
Oguro-Ando A, Rosensweig C, Herman E, Nishimura Y, Werling D, Bill BR, Berg JM, Gao F, Coppola G, Abrahams BS, Geschwind DH. Increased CYFIP1 dosage alters cellular and dendritic morphology and dysregulates mTOR. Mol Psychiatry 2015; 20:1069-78. [PMID: 25311365 PMCID: PMC4409498 DOI: 10.1038/mp.2014.124] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 07/18/2014] [Accepted: 08/21/2014] [Indexed: 12/22/2022]
Abstract
Rare maternally inherited duplications at 15q11-13 are observed in ~1% of individuals with an autism spectrum disorder (ASD), making it among the most common causes of ASD. 15q11-13 comprises a complex region, and as this copy number variation encompasses many genes, it is important to explore individual genotype-phenotype relationships. Cytoplasmic FMR1-interacting protein 1 (CYFIP1) is of particular interest because of its interaction with Fragile X mental retardation protein (FMRP), its upregulation in transformed lymphoblastoid cell lines from patients with duplications at 15q11-13 and ASD and the presence of smaller overlapping deletions of CYFIP1 in patients with schizophrenia and intellectual disability. Here, we confirm that CYFIP1 is upregulated in transformed lymphoblastoid cell lines and demonstrate its upregulation in the post-mortem brain from 15q11-13 duplication patients for the first time. To investigate how increased CYFIP1 dosage might predispose to neurodevelopmental disease, we studied the consequence of its overexpression in multiple systems. We show that overexpression of CYFIP1 results in morphological abnormalities including cellular hypertrophy in SY5Y cells and differentiated mouse neuronal progenitors. We validate these results in vivo by generating a BAC transgenic mouse, which overexpresses Cyfip1 under the endogenous promotor, observing an increase in the proportion of mature dendritic spines and dendritic spine density. Gene expression profiling on embryonic day 15 suggested the dysregulation of mammalian target of rapamycin (mTOR) signaling, which was confirmed at the protein level. Importantly, similar evidence of mTOR-related dysregulation was seen in brains from 15q11-13 duplication patients with ASD. Finally, treatment of differentiated mouse neuronal progenitors with an mTOR inhibitor (rapamycin) rescued the morphological abnormalities resulting from CYFIP1 overexpression. Together, these data show that CYFIP1 overexpression results in specific cellular phenotypes and implicate modulation by mTOR signaling, further emphasizing its role as a potential convergent pathway in some forms of ASD.
Collapse
Affiliation(s)
- A Oguro-Ando
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
,Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands
| | - C Rosensweig
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - E Herman
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - Y Nishimura
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - D Werling
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - BR Bill
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - JM Berg
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - F Gao
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - G Coppola
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
,Semel Institute, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South, Los Angeles, CA 90095-1761
| | - BS Abrahams
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
| | - DH Geschwind
- Programs in Neurogenetics, Department of. Neurology and Program in Neurobehavioral Genetics and Center for Autism Research and Treatment, Semel Institute for Neuroscience and Behavior, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South Los Angeles, CA 90095-1761
,Dept. of Human Genetics, David Geffen School of Medicine, University of California at Los Angeles, 2309 Gonda Bldg, 695 Charles E. Young Dr. South, Los Angeles, CA 90095-1761
,
| |
Collapse
|
37
|
Gross C, Hoffmann A, Bassell GJ, Berry-Kravis EM. Therapeutic Strategies in Fragile X Syndrome: From Bench to Bedside and Back. Neurotherapeutics 2015; 12:584-608. [PMID: 25986746 PMCID: PMC4489963 DOI: 10.1007/s13311-015-0355-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Fragile X syndrome (FXS), an inherited intellectual disability often associated with autism, is caused by the loss of expression of the fragile X mental retardation protein. Tremendous progress in basic, preclinical, and translational clinical research has elucidated a variety of molecular-, cellular-, and system-level defects in FXS. This has led to the development of several promising therapeutic strategies, some of which have been tested in larger-scale controlled clinical trials. Here, we will summarize recent advances in understanding molecular functions of fragile X mental retardation protein beyond the well-known role as an mRNA-binding protein, and will describe current developments and emerging limitations in the use of the FXS mouse model as a preclinical tool to identify therapeutic targets. We will review the results of recent clinical trials conducted in FXS that were based on some of the preclinical findings, and discuss how the observed outcomes and obstacles will inform future therapy development in FXS and other autism spectrum disorders.
Collapse
Affiliation(s)
- Christina Gross
- />Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229 USA
| | - Anne Hoffmann
- />Department of Pediatrics, Rush University Medical Center, Chicago, IL 60612 USA
| | - Gary J. Bassell
- />Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Elizabeth M. Berry-Kravis
- />Departments of Pediatrics, Neurological Sciences, Biochemistry, Rush University Medical Center, Chicago, IL 60612 USA
| |
Collapse
|
38
|
Are Angelman and Prader-Willi syndromes more similar than we thought? Food-related behavior problems in Angelman, Cornelia de Lange, Fragile X, Prader-Willi and 1p36 deletion syndromes. Am J Med Genet A 2015; 167A:572-8. [DOI: 10.1002/ajmg.a.36923] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 11/21/2014] [Indexed: 11/07/2022]
|
39
|
Lumaban JG, Nelson DL. The Fragile X proteins Fmrp and Fxr2p cooperate to regulate glucose metabolism in mice. Hum Mol Genet 2014; 24:2175-84. [PMID: 25552647 DOI: 10.1093/hmg/ddu737] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Fragile X syndrome results from loss of FMR1 expression. Individuals with the disorder exhibit not only intellectual disability, but also an array of physical and behavioral abnormalities, including sleep difficulties. Studies in mice demonstrated that Fmr1, along with its paralog Fxr2, regulate circadian behavior, and that their absence disrupts expression and cycling of essential clock mRNAs in the liver. Recent reports have identified circadian genes to be essential for normal metabolism. Here we describe the metabolic defects that arise in mice mutated for both Fmr1 and Fxr2. These mice have reduced fat deposits compared with age- and weight-matched controls. Several metabolic markers show either low levels in plasma or abnormal circadian cycling (or both). Insulin levels are consistently low regardless of light exposure and feeding conditions, and the animals are extremely sensitive to injected insulin. Glucose production from introduced pyruvate and glucagon is impaired and the mice quickly clear injected glucose. These mice also have higher food intake and higher VO2 and VCO2 levels. We analyzed liver expression of genes involved in glucose homeostasis and found several that are expressed differentially in the mutant mice. These results point to the involvement of Fmr1 and Fxr2 in maintaining the normal metabolic state in mice.
Collapse
Affiliation(s)
- Jeannette G Lumaban
- Department of Molecular and Human Genetics, Jan and Dan Duncan Neurological Research Institute, Baylor College of Medicine, 1250 Moursund Street, Houston, TX 77030, USA
| | - David L Nelson
- Department of Molecular and Human Genetics, Jan and Dan Duncan Neurological Research Institute, Baylor College of Medicine, 1250 Moursund Street, Houston, TX 77030, USA
| |
Collapse
|
40
|
Pugin A, Faundes V, Santa María L, Curotto B, Aliaga S, Salas I, Soto P, Bravo P, Peña MI, Alliende MA. Clinical, molecular, and pharmacological aspects of FMR1 related disorders. Neurologia 2014; 32:241-252. [PMID: 25529181 DOI: 10.1016/j.nrl.2014.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 10/08/2014] [Accepted: 10/23/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Fragile X syndrome, the most common inherited cause of intellectual disability, is associated with a broad spectrum of disorders across different generations of a single family. This study reviews the clinical manifestations of fragile X-associated disorders as well as the spectrum of mutations of the fragile X mental retardation 1 gene (FMR1) and the neurobiology of the fragile X mental retardation protein (FMRP), and also provides an overview of the potential therapeutic targets and genetic counselling. DEVELOPMENT This disorder is caused by expansion of the CGG repeat (>200 repeats) in the 5 prime untranslated region of FMR1, resulting in a deficit or absence of FMRP. FMRP is an RNA-binding protein that regulates the translation of several genes that are important in synaptic plasticity and dendritic maturation. It is believed that CGG repeat expansions in the premutation range (55 to 200 repeats) elicit an increase in mRNA levels of FMR1, which may cause neuronal toxicity. These changes manifest clinically as developmental problems such as autism and learning disabilities as well as neurodegenerative diseases including fragile X-associated tremor/ataxia syndrome (FXTAS). CONCLUSIONS Advances in identifying the molecular basis of fragile X syndrome may help us understand the causes of neuropsychiatric disorders, and they will probably contribute to development of new and specific treatments.
Collapse
Affiliation(s)
- A Pugin
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - V Faundes
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile.
| | - L Santa María
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - B Curotto
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - S Aliaga
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - I Salas
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - P Soto
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - P Bravo
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - M I Peña
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| | - M A Alliende
- Laboratorio de Genética y Enfermedades Metabólicas, Instituto de Nutrición y Tecnología de los Alimentos (INTA), Universidad de Chile, Santiago, Chile
| |
Collapse
|
41
|
Lozano R, Rosero CA, Hagerman RJ. Fragile X spectrum disorders. Intractable Rare Dis Res 2014; 3:134-46. [PMID: 25606363 PMCID: PMC4298643 DOI: 10.5582/irdr.2014.01022] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 11/28/2014] [Indexed: 12/13/2022] Open
Abstract
The fragile X mental retardation 1 gene (FMR1), which codes for the fragile X mental retardation 1 protein (FMRP), is located at Xp27.3. The normal allele of the FMR1 gene typically has 5 to 40 CGG repeats in the 5' untranslated region; abnormal alleles of dynamic mutations include the full mutation (> 200 CGG repeats), premutation (55-200 CGG repeats) and the gray zone mutation (45-54 CGG repeats). Premutation carriers are common in the general population with approximately 1 in 130-250 females and 1 in 250-810 males, whereas the full mutation and Fragile X syndrome (FXS) occur in approximately 1 in 4000 to 1 in 7000. FMR1 mutations account for a variety of phenotypes including the most common monogenetic cause of inherited intellectual disability (ID) and autism (FXS), the most common genetic form of ovarian failure, the fragile X-associated primary ovarian insufficiency (FXPOI, premutation); and fragile X-associated tremor/ataxia syndrome (FXTAS, premutation). The premutation can also cause developmental problems including ASD and ADHD especially in boys and psychopathology including anxiety and depression in children and adults. Some premutation carriers can have a deficit of FMRP and some unmethylated full mutation individuals can have elevated FMR1 mRNA that is considered a premutation problem. Therefore the term "Fragile X Spectrum Disorder" (FXSD) should be used to include the wide range of overlapping phenotypes observed in affected individuals with FMR1 mutations. In this review we focus on the phenotypes and genotypes of children with FXSD.
Collapse
Affiliation(s)
- Reymundo Lozano
- UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
- Address correspondence to: Dr. Reymundo Lozano, UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA. E-mail:
| | - Carolina Alba Rosero
- Instituto Colombiano del Sistema Nervioso, Clínica Montserrat, Bogotá D.C, Colombia
| | - Randi J Hagerman
- UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| |
Collapse
|
42
|
Usdin K, Hayward BE, Kumari D, Lokanga RA, Sciascia N, Zhao XN. Repeat-mediated genetic and epigenetic changes at the FMR1 locus in the Fragile X-related disorders. Front Genet 2014; 5:226. [PMID: 25101111 PMCID: PMC4101883 DOI: 10.3389/fgene.2014.00226] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 06/29/2014] [Indexed: 01/01/2023] Open
Abstract
The Fragile X-related disorders are a group of genetic conditions that include the neurodegenerative disorder, Fragile X-associated tremor/ataxia syndrome (FXTAS), the fertility disorder, Fragile X-associated primary ovarian insufficiency (FXPOI) and the intellectual disability, Fragile X syndrome (FXS). The pathology in all these diseases is related to the number of CGG/CCG-repeats in the 5′ UTR of the Fragile X mental retardation 1 (FMR1) gene. The repeats are prone to continuous expansion and the increase in repeat number has paradoxical effects on gene expression increasing transcription on mid-sized alleles and decreasing it on longer ones. In some cases the repeats can simultaneously both increase FMR1 mRNA production and decrease the levels of the FMR1 gene product, Fragile X mental retardation 1 protein (FMRP). Since FXTAS and FXPOI result from the deleterious consequences of the expression of elevated levels of FMR1 mRNA and FXS is caused by an FMRP deficiency, the clinical picture is turning out to be more complex than once appreciated. Added complications result from the fact that increasing repeat numbers make the alleles somatically unstable. Thus many individuals have a complex mixture of different sized alleles in different cells. Furthermore, it has become apparent that the eponymous fragile site, once thought to be no more than a useful diagnostic criterion, may have clinical consequences for females who inherit chromosomes that express this site. This review will cover what is currently known about the mechanisms responsible for repeat instability, for the repeat-mediated epigenetic changes that affect expression of the FMR1 gene, and for chromosome fragility. It will also touch on what current and future options are for ameliorating some of these effects.
Collapse
Affiliation(s)
- Karen Usdin
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD, USA
| | - Bruce E Hayward
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD, USA
| | - Daman Kumari
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD, USA
| | - Rachel A Lokanga
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD, USA
| | - Nicholas Sciascia
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD, USA
| | - Xiao-Nan Zhao
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda MD, USA
| |
Collapse
|
43
|
Abekhoukh S, Bardoni B. CYFIP family proteins between autism and intellectual disability: links with Fragile X syndrome. Front Cell Neurosci 2014; 8:81. [PMID: 24733999 PMCID: PMC3973919 DOI: 10.3389/fncel.2014.00081] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Accepted: 02/27/2014] [Indexed: 12/14/2022] Open
Abstract
Intellectual disability (ID) and autism spectrum disorders (ASDs) have in common alterations in some brain circuits and brain abnormalities, such as synaptic transmission and dendritic spines morphology. Recent studies have indicated a differential expression for specific categories of genes as a cause for both types of disease, while an increasing number of genes is recognized to produce both disorders. An example is the Fragile X mental retardation gene 1 (FMR1), whose silencing causes the Fragile X syndrome, the most common form of ID and autism, also characterized by physical hallmarks. Fragile X mental retardation protein (FMRP), the protein encoded by FMR1, is an RNA-binding protein with an important role in translational control. Among the interactors of FMRP, CYFIP1/2 (cytoplasmic FMRP interacting protein) proteins are good candidates for ID and autism, on the bases of their genetic implication and functional properties, even if the precise functional significance of the CYFIP/FMRP interaction is not understood yet. CYFIP1 and CYFIP2 represent a link between Rac1, the WAVE (WAS protein family member) complex and FMRP, favoring the cross talk between actin polymerization and translational control.
Collapse
Affiliation(s)
- Sabiha Abekhoukh
- CNRS, Institute of Molecular and Cellular Pharmacology, UMR 7275 Valbonne, France ; University of Nice Sophia-Antipolis Nice, France ; CNRS, International Associated Laboratories-NEOGENEX Valbonne, France
| | - Barbara Bardoni
- CNRS, Institute of Molecular and Cellular Pharmacology, UMR 7275 Valbonne, France ; University of Nice Sophia-Antipolis Nice, France ; CNRS, International Associated Laboratories-NEOGENEX Valbonne, France
| |
Collapse
|
44
|
Coppus AMW. People with intellectual disability: what do we know about adulthood and life expectancy? ACTA ACUST UNITED AC 2014; 18:6-16. [PMID: 23949824 DOI: 10.1002/ddrr.1123] [Citation(s) in RCA: 210] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 12/03/2012] [Accepted: 12/20/2012] [Indexed: 12/13/2022]
Abstract
Increases in the life expectancy of people with Intellectual Disability have followed similar trends to those found in the general population. With the exception of people with severe and multiple disabilities or Down syndrome, the life expectancy of this group now closely approximates with that of the general population. Middle and old age, which until 30 years ago were not recognized in this population, are now important parts of the life course of these individuals. Older adults with Intellectual Disabilities form a small, but significant and growing proportion of older people in the community. How these persons grow older and how symptoms and complications of the underlying cause of the Intellectual Disability will influence their life expectancy is of the utmost importance.
Collapse
Affiliation(s)
- A M W Coppus
- Dichterbij, Center for the Intellectually Disabled, Medical Center, Gennep, The Netherlands.
| |
Collapse
|
45
|
Zink AM, Wohlleber E, Engels H, Rødningen OK, Ravn K, Heilmann S, Rehnitz J, Katzorke N, Kraus C, Blichfeldt S, Hoffmann P, Reutter H, Brockschmidt FF, Kreiß-Nachtsheim M, Vogt PH, Prescott TE, Tümer Z, Lee JA. Microdeletions including FMR1 in three female patients with intellectual disability - further delineation of the phenotype and expression studies. Mol Syndromol 2014; 5:65-75. [PMID: 24715853 DOI: 10.1159/000357962] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2013] [Indexed: 11/19/2022] Open
Abstract
Fragile X syndrome (FXS) is one of the most common causes of intellectual disability/developmental delay (ID/DD), especially in males. It is caused most often by CGG trinucleotide repeat expansions, and less frequently by point mutations and partial or full deletions of the FMR1 gene. The wide clinical spectrum of affected females partly depends on their X-inactivation status. Only few female ID/DD patients with microdeletions including FMR1 have been reported. We describe 3 female patients with 3.5-, 4.2- and 9.2-Mb de novo microdeletions in Xq27.3-q28 containing FMR1. X-inactivation was random in all patients, yet they presented with ID/DD as well as speech delay, macrocephaly and other features attributable to FXS. No signs of autism were present. Here, we further delineate the clinical spectrum of female patients with microdeletions. FMR1 expression studies gave no evidence for an absolute threshold below which signs of FXS present. Since FMR1 expression is known to be highly variable between unrelated females, and since FMR1 mRNA levels have been suggested to be more similar among family members, we further explored the possibility of an intrafamilial effect. Interestingly, FMR1 mRNA levels in all 3 patients were significantly lower than in their respective mothers, which was shown to be specific for patients with microdeletions containing FMR1.
Collapse
Affiliation(s)
- A M Zink
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - E Wohlleber
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - H Engels
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - O K Rødningen
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - K Ravn
- Applied Human Molecular Genetics, Kennedy Center, Glostrup, Denmark
| | - S Heilmann
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Department of Genomics, Life & Brain Center, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - J Rehnitz
- Molecular Genetics and Infertility Unit, Department of Gynecology, Endocrinology and Reproductive Medicine, University Women Hospital, Heidelberg, Germany
| | - N Katzorke
- Molecular Genetics and Infertility Unit, Department of Gynecology, Endocrinology and Reproductive Medicine, University Women Hospital, Heidelberg, Germany
| | - C Kraus
- Institute of Human Genetics, Friedrich-Alexander-University, Erlangen-Nuremberg, Germany
| | - S Blichfeldt
- Pediatric Department L55, Glostrup University Hospital, Glostrup, Denmark
| | - P Hoffmann
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Department of Genomics, Life & Brain Center, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Medical Genetics, Department of Biomedicine, University Hospital, Basel, Switzerland
| | - H Reutter
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Department of Neonatology, Children's Hospital, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - F F Brockschmidt
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Department of Genomics, Life & Brain Center, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - M Kreiß-Nachtsheim
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - P H Vogt
- Molecular Genetics and Infertility Unit, Department of Gynecology, Endocrinology and Reproductive Medicine, University Women Hospital, Heidelberg, Germany
| | - T E Prescott
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
| | - Z Tümer
- Applied Human Molecular Genetics, Kennedy Center, Glostrup, Denmark ; Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - J A Lee
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Department of Genomics, Life & Brain Center, Rheinische Friedrich-Wilhelms-University, Bonn, Germany ; Greenwood Genetic Center, Greenwood, S.C., USA
| |
Collapse
|
46
|
Common variants in genes of the postsynaptic FMRP signalling pathway are risk factors for autism spectrum disorders. Hum Genet 2014; 133:781-92. [PMID: 24442360 DOI: 10.1007/s00439-013-1416-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 12/25/2013] [Indexed: 10/25/2022]
Abstract
Autism spectrum disorders (ASD) are heterogeneous disorders with a high heritability and complex genetic architecture. Due to the central role of the fragile X mental retardation gene 1 protein (FMRP) pathway in ASD we investigated common functional variants of ASD risk genes regulating FMRP. We genotyped ten SNPs in two German patient sets (N = 192 and N = 254 families, respectively) and report association for rs7170637 (CYFIP1; set 1 and combined sets), rs6923492 (GRM1; combined sets), and rs25925 (CAMK4; combined sets). An additional risk score based on variants with an odds ratio (OR) >1.25 in set 1 and weighted by their respective log transmitted/untransmitted ratio revealed a significant effect (OR 1.30, 95 % CI 1.11-1.53; P = 0.0013) in the combined German sample. A subsequent meta-analysis including the two German samples, the "Strict/European" ASD subsample of the Autism Genome Project (1,466 families) and a French case/control (541/366) cohort showed again association of rs7170637-A (OR 0.85, 95 % CI 0.75-0.96; P = 0.007) and rs25925-G (OR 1.31, 95 % CI 1.04-1.64; P = 0.021) with ASD. Functional analyses revealed that these minor alleles predicted to alter splicing factor binding sites significantly increase levels of an alternative mRNA isoform of the respective gene while keeping the overall expression of the gene constant. These findings underpin the role of ASD candidate genes in postsynaptic FMRP regulation suggesting that an imbalance of specific isoforms of CYFIP1, an FMRP interaction partner, and CAMK4, a transcriptional regulator of the FMRP gene, modulates ASD risk. Both gene products are related to neuronal regulation of synaptic plasticity, a pathomechanism underlying ASD and may thus present future targets for pharmacological therapies in ASD.
Collapse
|
47
|
Abstract
Research suggests that the prevalence of obesity in children with autism spectrum disorder (ASD) is at least as high as that seen in typically developing children. Many of the risk factors for children with ASD are likely the same as for typically developing children, especially within the context of today's obesogenic environment. The particular needs and challenges that this population faces, however, may render them more susceptible to the adverse effects of typical risk factors, and they may also be vulnerable to additional risk factors not shared by children in the general population, including psychopharmacological treatment, genetics, disordered sleep, atypical eating patterns, and challenges for engaging in sufficient physical activity. For individuals with ASD, obesity and its sequelae potentially represent a significant threat to independent living, self-care, quality of life, and overall health.
Collapse
|
48
|
Jacquemont S, Berry-Kravis E, Hagerman R, von Raison F, Gasparini F, Apostol G, Ufer M, Des Portes V, Gomez-Mancilla B. The challenges of clinical trials in fragile X syndrome. Psychopharmacology (Berl) 2014; 231:1237-50. [PMID: 24173622 PMCID: PMC3932172 DOI: 10.1007/s00213-013-3289-0] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 09/05/2013] [Indexed: 11/28/2022]
Abstract
RATIONALE Advances in understanding the underlying mechanisms of conditions such as fragile X syndrome (FXS) and autism spectrum disorders have revealed heterogeneous populations. Recent trials of novel FXS therapies have highlighted several challenges including subpopulations with possibly differential therapeutic responses, the lack of specific outcome measures capturing the full range of improvements of patients with FXS, and a lack of biomarkers that can track whether a specific mechanism is responsive to a new drug and whether the response correlates with clinical improvement. OBJECTIVES We review the phenotypic heterogeneity of FXS and the implications for clinical research in FXS and other neurodevelopmental disorders. RESULTS Residual levels of fragile X mental retardation protein (FMRP) expression explain in part the heterogeneity in the FXS phenotype; studies indicate a correlation with both cognitive and behavioral deficits. However, this does not fully explain the extent of phenotypic variance observed or the variability of drug response. Post hoc analyses of studies involving the selective mGluR5 antagonist mavoglurant and the GABAB agonist arbaclofen have uncovered significant therapeutic responses following patient stratification according to FMR1 promoter methylation patterns or baseline severity of social withdrawal, respectively. Future studies designed to quantify disease modification will need to develop new strategies to track changes effectively over time and in multiple symptom domains. CONCLUSION Appropriate selection of patients and outcome measures is central to optimizing future clinical investigations of these complex disorders.
Collapse
Affiliation(s)
- Sébastien Jacquemont
- Service de Génétique Médicale, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
| | - Elizabeth Berry-Kravis
- Departments of Pediatrics, Neurological Sciences and Biochemistry, Rush University Medical Center, Chicago, IL 60612 USA
| | - Randi Hagerman
- MIND Institute and Department of Pediatrics, UC Davis Health System, Sacramento, CA 95817 USA
| | | | - Fabrizio Gasparini
- Novartis Institutes for BioMedical Research Basel, Forum 1, Novartis Campus, 4056 Basel, Switzerland
| | - George Apostol
- Neuroscience Development, Novartis Pharma AG, 4056 Basel, Switzerland
| | - Mike Ufer
- Novartis Institutes for BioMedical Research Basel, Forum 1, Novartis Campus, 4056 Basel, Switzerland
| | - Vincent Des Portes
- National Reference Center for Fragile X and Other XLMR, Hospices Civils de Lyon, Université de Lyon and CNRS UMR 5304 (L2C2), Bron, France
| | - Baltazar Gomez-Mancilla
- Novartis Institutes for BioMedical Research Basel, Forum 1, Novartis Campus, 4056 Basel, Switzerland
| |
Collapse
|
49
|
De Rubeis S, Pasciuto E, Li K, Fernández E, Di Marino D, Buzzi A, Ostroff L, Klann E, Zwartkruis FJ, Komiyama N, Grant SG, Poujol C, Choquet D, Achsel T, Posthuma D, Smit A, Bagni C. CYFIP1 coordinates mRNA translation and cytoskeleton remodeling to ensure proper dendritic spine formation. Neuron 2013; 79:1169-82. [PMID: 24050404 PMCID: PMC3781321 DOI: 10.1016/j.neuron.2013.06.039] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2013] [Indexed: 11/30/2022]
Abstract
The CYFIP1/SRA1 gene is located in a chromosomal region linked to various neurological disorders, including intellectual disability, autism, and schizophrenia. CYFIP1 plays a dual role in two apparently unrelated processes, inhibiting local protein synthesis and favoring actin remodeling. Here, we show that brain-derived neurotrophic factor (BDNF)-driven synaptic signaling releases CYFIP1 from the translational inhibitory complex, triggering translation of target mRNAs and shifting CYFIP1 into the WAVE regulatory complex. Active Rac1 alters the CYFIP1 conformation, as demonstrated by intramolecular FRET, and is key in changing the equilibrium of the two complexes. CYFIP1 thus orchestrates the two molecular cascades, protein translation and actin polymerization, each of which is necessary for correct spine morphology in neurons. The CYFIP1 interactome reveals many interactors associated with brain disorders, opening new perspectives to define regulatory pathways shared by neurological disabilities characterized by spine dysmorphogenesis.
Collapse
Affiliation(s)
- Silvia De Rubeis
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
| | - Emanuela Pasciuto
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
| | - Ka Wan Li
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Medical Center Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Esperanza Fernández
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
| | - Daniele Di Marino
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
| | - Andrea Buzzi
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
| | | | - Eric Klann
- Center for Neural Science, New York University, New York, NY 10003, USA
| | - Fried J.T. Zwartkruis
- Molecular Cancer Research, Center for Biomedical Genetics and Cancer Genomics Center, University Medical Center Utrecht, 3584 CG Utrecht
| | - Noboru H. Komiyama
- Centre for Clinical Brain Sciences and Centre for Neuroregeneration, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Seth G.N. Grant
- Centre for Clinical Brain Sciences and Centre for Neuroregeneration, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Christel Poujol
- CNRS, Bordeaux Imaging Center, UMS 3420, 33000 Bordeaux, France
- University of Bordeaux, UMS 3420, 33077, Bordeaux, France
| | - Daniel Choquet
- CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, 33000 Bordeaux, France
- University of Bordeaux, UMR 5297, 33077, Bordeaux, France
| | - Tilmann Achsel
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
| | - Danielle Posthuma
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Medical Center Amsterdam, 1081 HV Amsterdam, The Netherlands
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Medical Center Amsterdam, 1081 HV Amsterdam, The Netherlands
- Department of Child and Adolescent Psychiatry, Erasmus University Medical Center/Sophia Child Hospital, 3000 CB Rotterdam, The Netherlands
| | - August B. Smit
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Medical Center Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Claudia Bagni
- VIB Center for Biology of Disease, KULeuven, 3000 Leuven, Belgium
- Center for Human Genetics and Leuven Institute for Neuroscience and Disease (LIND), KULeuven, 3000 Leuven, Belgium
- Department of Biomedicine and Prevention, University “Tor Vergata,” 00133 Rome, Italy
| |
Collapse
|
50
|
Autism-related deficits via dysregulated eIF4E-dependent translational control. Nature 2012; 493:371-7. [PMID: 23172145 DOI: 10.1038/nature11628] [Citation(s) in RCA: 389] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 09/28/2012] [Indexed: 01/06/2023]
Abstract
Hyperconnectivity of neuronal circuits due to increased synaptic protein synthesis is thought to cause autism spectrum disorders (ASDs). The mammalian target of rapamycin (mTOR) is strongly implicated in ASDs by means of upstream signalling; however, downstream regulatory mechanisms are ill-defined. Here we show that knockout of the eukaryotic translation initiation factor 4E-binding protein 2 (4E-BP2)-an eIF4E repressor downstream of mTOR-or eIF4E overexpression leads to increased translation of neuroligins, which are postsynaptic proteins that are causally linked to ASDs. Mice that have the gene encoding 4E-BP2 (Eif4ebp2) knocked out exhibit an increased ratio of excitatory to inhibitory synaptic inputs and autistic-like behaviours (that is, social interaction deficits, altered communication and repetitive/stereotyped behaviours). Pharmacological inhibition of eIF4E activity or normalization of neuroligin 1, but not neuroligin 2, protein levels restores the normal excitation/inhibition ratio and rectifies the social behaviour deficits. Thus, translational control by eIF4E regulates the synthesis of neuroligins, maintaining the excitation-to-inhibition balance, and its dysregulation engenders ASD-like phenotypes.
Collapse
|