1
|
Zhou BB, Chen X, Zhang C, Wang YP, Ma PP, Hao SJ, Hui L, Bai YF. Analysis of spinal muscular atrophy carrier screening results in 32,416 pregnant women and 7,231 prepregnant women. Front Neurol 2024; 15:1357476. [PMID: 38654739 PMCID: PMC11035774 DOI: 10.3389/fneur.2024.1357476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 03/28/2024] [Indexed: 04/26/2024] Open
Abstract
Objectives Spinal muscular atrophy (SMA) is an autosomal recessive disease that is one of the most common in childhood neuromuscular disorders. Our screenings are more meaningful programs in preventing birth defects, providing a significant resource for healthcare professionals, genetic counselors, and policymakers involved in designing strategies to prevent and manage SMA. Method We screened 39,647 participants from 2020 to the present by quantitative real-time PCR, including 7,231 pre-pregnancy participants and 32,416 pregnancy participants, to detect the presence of SMN1 gene EX7 and EX8 deletion in the DNA samples provided by the subjects. To validate the accuracy of our findings, we also utilized the Multiplex Ligation-dependent Probe Amplification (MLPA) to confirm the reliability of screening results obtained by quantitative real-time PCR. Result Among the 39,647 participants who were screened, 726 participants were the carriers of SMN1. The overall carrier rate was calculated to be 1.83% (95% confidence interval: 0.86-2.8%). After undergoing screening, a total of 592 pregnancy carriers were provided with genetic counseling and only 503 of their spouses (84.97, 95% confidence interval: 82.09-87.85%) voluntarily underwent SMA screening. Conclusion This study provides crucial insights into the prevalence and distribution of SMA carriers among the female population. The identification of 726 asymptomatic carriers highlights the necessity of comprehensive screening programs to identify at-risk individuals and ensure appropriate interventions are in place to minimize the impact of SMA-related conditions.
Collapse
Affiliation(s)
- Bing-bo Zhou
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Xue Chen
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Chuan Zhang
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Yu-pei Wang
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Pan-pan Ma
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Sheng-ju Hao
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | - Ling Hui
- The Center for Medical Genetics in Gansu Provincial Maternity and Child-care Hospital, Gansu Provincial Clinical Research Center for Birth Defects and Rare Diseases, Lanzhou, China
| | | |
Collapse
|
2
|
Oskoui M, Servais L. Spinal Muscular Atrophy. Continuum (Minneap Minn) 2023; 29:1564-1584. [PMID: 37851043 DOI: 10.1212/con.0000000000001338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
OBJECTIVE This article provides a comprehensive overview of the diagnostic assessment and treatment of individuals with spinal muscular atrophy (SMA) due to homozygous deletions of SMN1 . LATEST DEVELOPMENTS In recent years, most states have incorporated SMA in their newborn screening panel. To provide the earliest diagnosis possible after symptom onset, vigilance is needed for births in states without newborn screening for SMA and when compound heterozygotes are missed by newborn screening programs. Supportive care for respiratory, nutritional, and orthopedic health impacts outcomes and is the cornerstone of care. Adaptive equipment, including assistive home technology, enables affected individuals to gain autonomy in their daily activities. Pharmacologic treatments approved by the US Food and Drug Administration (FDA) include three drugs that increase deficient survival motor neuron protein levels through SMN1 - or SMN2 - directed pathways: nusinersen, onasemnogene abeparvovec, and risdiplam. Efficacy for these trials was measured in event-free survival (survival without the need for permanent ventilation) and gains in functional motor outcomes. Earlier treatment is most effective across all treatments. ESSENTIAL POINTS The diagnostic and therapeutic landscapes for SMA have seen dramatic advancements in recent years, improving prognosis. Optimized supportive care remains essential, and vigilance is needed to define the new natural history of this disease.
Collapse
|
3
|
Fay A. Spinal Muscular Atrophy: A (Now) Treatable Neurodegenerative Disease. Pediatr Clin North Am 2023; 70:963-977. [PMID: 37704354 DOI: 10.1016/j.pcl.2023.06.002] [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] [Indexed: 09/15/2023]
Abstract
Spinal muscular atrophy (SMA) is a progressive disease of the lower motor neurons associated with recessive loss of the SMN1 gene, and which leads to worsening weakness and disability, and is fatal in its most severe forms. Over the past six years, three treatments have emerged, two drugs that modify exon splicing and one gene therapy, which have transformed the management of this disease. When treated pre-symptomatically, many children show normal early motor development, and the benefits extend from the newborn period to adulthood. Similar treatment approaches are now under investigation for rare types of SMA associated with genes beyond SMN1.
Collapse
Affiliation(s)
- Alex Fay
- University of California, San Francisco, 1875 4th Street., Suite 5A, San Francisco, CA 94158, USA.
| |
Collapse
|
4
|
Jha NN, Kim JK, Her YR, Monani UR. Muscle: an independent contributor to the neuromuscular spinal muscular atrophy disease phenotype. JCI Insight 2023; 8:e171878. [PMID: 37737261 PMCID: PMC10561723 DOI: 10.1172/jci.insight.171878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/23/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a pediatric-onset neuromuscular disorder caused by insufficient survival motor neuron (SMN) protein. SMN restorative therapies are now approved for the treatment of SMA; however, they are not curative, likely due to a combination of imperfect treatment timing, inadequate SMN augmentation, and failure to optimally target relevant organs. Here, we consider the implications of imperfect treatment administration, focusing specifically on outcomes for skeletal muscle. We examine the evidence that muscle plays a contributing role in driving neuromuscular dysfunction in SMA. Next, we discuss how SMN might regulate the health of myofibers and their progenitors. Finally, we speculate on therapeutic outcomes of failing to raise muscle SMN to healthful levels and present strategies to restore function to this tissue to ensure better treatment results.
Collapse
Affiliation(s)
- Narendra N. Jha
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
| | - Jeong-Ki Kim
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
| | - Yoon-Ra Her
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
| | - Umrao R. Monani
- Department of Neurology
- Center for Motor Neuron Biology and Disease, and
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| |
Collapse
|
5
|
Nishio H, Niba ETE, Saito T, Okamoto K, Takeshima Y, Awano H. Spinal Muscular Atrophy: The Past, Present, and Future of Diagnosis and Treatment. Int J Mol Sci 2023; 24:11939. [PMID: 37569314 PMCID: PMC10418635 DOI: 10.3390/ijms241511939] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/17/2023] [Accepted: 07/21/2023] [Indexed: 08/13/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a lower motor neuron disease with autosomal recessive inheritance. The first cases of SMA were reported by Werdnig in 1891. Although the phenotypic variation of SMA led to controversy regarding the clinical entity of the disease, the genetic homogeneity of SMA was proved in 1990. Five years later, in 1995, the gene responsible for SMA, SMN1, was identified. Genetic testing of SMN1 has enabled precise epidemiological studies, revealing that SMA occurs in 1 of 10,000 to 20,000 live births and that more than 95% of affected patients are homozygous for SMN1 deletion. In 2016, nusinersen was the first drug approved for treatment of SMA in the United States. Two other drugs were subsequently approved: onasemnogene abeparvovec and risdiplam. Clinical trials with these drugs targeting patients with pre-symptomatic SMA (those who were diagnosed by genetic testing but showed no symptoms) revealed that such patients could achieve the milestones of independent sitting and/or walking. Following the great success of these trials, population-based newborn screening programs for SMA (more precisely, SMN1-deleted SMA) have been increasingly implemented worldwide. Early detection by newborn screening and early treatment with new drugs are expected to soon become the standards in the field of SMA.
Collapse
Affiliation(s)
- Hisahide Nishio
- Faculty of Rehabilitation, Kobe Gakuin University, 518 Arise, Ikawadani-cho, Nishi-ku, Kobe 651-2180, Japan
| | - Emma Tabe Eko Niba
- Laboratory of Molecular and Biochemical Research, Biomedical Research Core Facilities, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan;
| | - Toshio Saito
- Department of Neurology, National Hospital Organization Osaka Toneyama Medical Center, 5-1-1 Toneyama, Toyonaka 560-8552, Japan;
| | - Kentaro Okamoto
- Department of Pediatrics, Ehime Prefectural Imabari Hospital, 4-5-5 Ishi-cho, Imabari 794-0006, Japan;
| | - Yasuhiro Takeshima
- Department of Pediatrics, Hyogo Medical University, 1-1 Mukogawacho, Nishinomiya 663-8501, Japan;
| | - Hiroyuki Awano
- Organization for Research Initiative and Promotion, Research Initiative Center, Tottori University, 86 Nishi-cho, Yonago 683-8503, Japan;
| |
Collapse
|
6
|
Rahman MM, Islam MR, Alam Tumpa MA, Shohag S, Shakil Khan Shuvo, Ferdous J, Kajol SA, Aljohani ASM, Al Abdulmonem W, Rauf A, Thiruvengadam M. Insights into the promising prospect of medicinal chemistry studies against neurodegenerative disorders. Chem Biol Interact 2023; 373:110375. [PMID: 36739931 DOI: 10.1016/j.cbi.2023.110375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/06/2022] [Accepted: 01/30/2023] [Indexed: 02/05/2023]
Abstract
Medicinal chemistry is an interdisciplinary field that incorporates organic chemistry, biochemistry, physical chemistry, pharmacology, informatics, molecular biology, structural biology, cell biology, and other disciplines. Additionally, it considers molecular factors such as the mode of action of the drugs, their chemical structure-activity relationship (SAR), and pharmacokinetic aspects like absorption, distribution, metabolism, elimination, and toxicity. Neurodegenerative disorders (NDs), which are defined by the breakdown of neurons over time, are affecting an increasing number of people. Oxidative stress, particularly the increased production of Reactive Oxygen Species (ROS), plays a crucial role in the growth of various disorders, as indicated by the identification of protein, lipid, and Deoxyribonucleic acid (DNA) oxidation products in vivo. Because of their inherent nature, most biological molecules are vulnerable to ROS, even if they play a role in metabolic parameters and cell signaling. Due to their high polyunsaturated fatty acid content, low antioxidant barrier, and high oxygen uptake, neurons are particularly vulnerable to oxidation by nature. As a result, excessive ROS generation in neurons looks especially harmful, and the mechanisms associated with biomolecule oxidative destruction are several and complex. This review focuses on the formation and management of ROS, as well as their chemical characteristics (both thermodynamic and kinetic), interactions, and implications in NDs.
Collapse
Affiliation(s)
- Md Mominur Rahman
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Md Rezaul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Mst Afroza Alam Tumpa
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Sheikh Shohag
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University Buraydah, 52571, Saudi Arabia
| | - Shakil Khan Shuvo
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Jannatul Ferdous
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Saima Akter Kajol
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, 1207, Bangladesh
| | - Abdullah S M Aljohani
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University Buraydah, 52571, Saudi Arabia
| | - Waleed Al Abdulmonem
- Department of Pathology, College of Medicine Qassim University, Buraydah, Saudi Arabia
| | - Abdur Rauf
- Department of Chemistry, University of Swabi, Swabi, Anbar, 23430, Khyber Pakhtunkhwa (KP), Pakistan.
| | - Muthu Thiruvengadam
- Department of Applied Bioscience, College of Life and Environmental Sciences, Konkuk University, Seoul, 05029, South Korea; Department of Microbiology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, 600077, Tamil Nadu, India.
| |
Collapse
|
7
|
Abstract
Spinal muscular atrophy (SMA) is caused by biallelic mutations in the SMN1 (survival motor neuron 1) gene on chromosome 5q13.2, which leads to a progressive degeneration of alpha motor neurons in the spinal cord and in motor nerve nuclei in the caudal brainstem. It is characterized by progressive proximally accentuated muscle weakness with loss of already acquired motor skills, areflexia and, depending on the phenotype, varying degrees of weakness of the respiratory and bulbar muscles. Over the past decade, disease-modifying therapies have become available based on splicing modulation of the SMN2 with SMN1 gene replacement, which if initiated significantly modifies the natural course of the disease. Newborn screening for SMA has been implemented in an increasing number of centers; however, available evidence for these new treatments is often limited to a small spectrum of patients concerning age and disease stage.
Collapse
Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
| | - Jerry R Mendell
- Department of Neurology and Pediatrics, Center for Gene Therapy, Abigail Wexner Research Institute, The Ohio State University, Nationwide Children's Hospital, Columbus, OH, United States
| |
Collapse
|
8
|
Blatnik AJ, McGovern VL, Burghes AHM. What Genetics Has Told Us and How It Can Inform Future Experiments for Spinal Muscular Atrophy, a Perspective. Int J Mol Sci 2021; 22:8494. [PMID: 34445199 PMCID: PMC8395208 DOI: 10.3390/ijms22168494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/28/2021] [Accepted: 08/04/2021] [Indexed: 02/06/2023] Open
Abstract
Proximal spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder characterized by motor neuron loss and subsequent atrophy of skeletal muscle. SMA is caused by deficiency of the essential survival motor neuron (SMN) protein, canonically responsible for the assembly of the spliceosomal small nuclear ribonucleoproteins (snRNPs). Therapeutics aimed at increasing SMN protein levels are efficacious in treating SMA. However, it remains unknown how deficiency of SMN results in motor neuron loss, resulting in many reported cellular functions of SMN and pathways affected in SMA. Herein is a perspective detailing what genetics and biochemistry have told us about SMA and SMN, from identifying the SMA determinant region of the genome, to the development of therapeutics. Furthermore, we will discuss how genetics and biochemistry have been used to understand SMN function and how we can determine which of these are critical to SMA moving forward.
Collapse
Affiliation(s)
| | | | - Arthur H. M. Burghes
- Department of Biological Chemistry & Pharmacology, The Ohio State University Wexner Medical Center, Rightmire Hall, Room 168, 1060 Carmack Road, Columbus, OH 43210, USA; (A.J.B.III); (V.L.M.)
| |
Collapse
|
9
|
Wadmann S, Hauge AM. Strategies of stratification: Regulating market access in the era of personalized medicine. SOCIAL STUDIES OF SCIENCE 2021; 51:628-653. [PMID: 33885344 DOI: 10.1177/03063127211005539] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Personalized medicine raises the stakes of pharmaceutical market regulation. Drawing on pragmatist valuation studies and science and technology studies literature on personalized medicine and pharmaceutical markets, this article demonstrates how complex negotiations about the value of a pharmaceutical can constitute a market in various ways, while also shaping the concerned patient populations. Tracing the path of a pharmacogenetic treatment, Spinraza, from its approval by the European Medicines Agency to its adoption in the publicly funded Danish healthcare system, we show how the market was formatted through particular stratifications of the patient population. We conceptualize these seemingly technical moves as strategies of stratification, that is, the application of techniques to assemble and divide data - and what data are meant to represent - into groups delineated by certain characteristics. We argue that stakeholders' use of strategies of stratification has important implications not only for market access, but also for the delineation of diseases and patient populations. Hence, it is crucial to make intelligible the mutual constitution of pharmaceutical markets and patient populations and the political efforts of delineating and connecting the two.
Collapse
Affiliation(s)
- Sarah Wadmann
- The Danish Center for Social Science Research - VIVE, Copenhagen, Denmark
| | | |
Collapse
|
10
|
Deutsch L, Osredkar D, Plavec J, Stres B. Spinal Muscular Atrophy after Nusinersen Therapy: Improved Physiology in Pediatric Patients with No Significant Change in Urine, Serum, and Liquor 1H-NMR Metabolomes in Comparison to an Age-Matched, Healthy Cohort. Metabolites 2021; 11:206. [PMID: 33808177 PMCID: PMC8065886 DOI: 10.3390/metabo11040206] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/25/2021] [Accepted: 03/29/2021] [Indexed: 02/07/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a genetically heterogeneous group of rare neuromuscular diseases and was until recently the most common genetic cause of death in children. The effects of 2-month nusinersen therapy on urine, serum, and liquor 1H-NMR metabolomes in SMA males and females were not explored yet, especially not in comparison to the urine 1H-NMR metabolomes of matching male and female cohorts. In this prospective, single-centered study, urine, serum, and liquor samples were collected from 25 male and female pediatric patients with SMA before and after 2 months of nusinersen therapy and urine samples from a matching healthy cohort (n = 125). Nusinersen intrathecal application was the first therapy for the treatment of SMA by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Metabolomes were analyzed using targeted metabolomics utilizing 600 MHz 1H-NMR, parametric and nonparametric multivariate statistical analyses, machine learning, and modeling. Medical assessment before and after nusinersen therapy showed significant improvements of movement, posture, and strength according to various medical tests. No significant differences were found in metabolomes before and after nusinersen therapy in urine, serum, and liquor samples using an ensemble of statistical and machine learning approaches. In comparison to a healthy cohort, 1H-NMR metabolomes of SMA patients contained a reduced number and concentration of urine metabolites and differed significantly between males and females as well. Significantly larger data scatter was observed for SMA patients in comparison to matched healthy controls. Machine learning confirmed urinary creatinine as the most significant, distinguishing SMA patients from the healthy cohort. The positive effects of nusinersen therapy clearly preceded or took place devoid of significant rearrangements in the 1H-NMR metabolomic makeup of serum, urine, and liquor. Urine creatinine was successful at distinguishing SMA patients from the matched healthy cohort, which is a simple systemic novelty linking creatinine and SMA to the physiology of inactivity and diabetes, and it facilitates the monitoring of SMA disease in pediatric patients through non-invasive urine collection.
Collapse
Affiliation(s)
- Leon Deutsch
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia;
| | - Damjan Osredkar
- Department of Pediatric Neurology, University Children’s Hospital, University Medical Centre Ljubljana, SI-1000 Ljubljana, Slovenia;
- Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Janez Plavec
- National Institute of Chemistry, NMR Center, SI-1000 Ljubljana, Slovenia;
| | - Blaž Stres
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia;
- Department of Automation, Biocybernetics and Robotics, Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
- Faculty of Civil and Geodetic Engineering, Institute of Sanitary Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia
- Department of Microbiology, University of Innsbruck, A-6020 Innsbruck, Austria
| |
Collapse
|
11
|
Vu-Han TL, Weiß C, Pumberger M. Novel therapies for spinal muscular atrophy are likely changing the patient phenotype. Spine J 2020; 20:1893-1898. [PMID: 32858169 DOI: 10.1016/j.spinee.2020.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/21/2020] [Accepted: 08/23/2020] [Indexed: 02/03/2023]
Affiliation(s)
- Tu-Lan Vu-Han
- Center for Musculoskeletal Surgery Berlin Mitte; Charité University Medicine Berlin, Charitéplatz 1, Berlin 10117, Germany.
| | - Claudia Weiß
- Center for chronically sick children, Department of Neuropediatrics; Charité University, Medicine Berlin, Augustenburger Platz 1, Berlin 13353, Germany
| | - Matthias Pumberger
- Center for Musculoskeletal Surgery Berlin Mitte; Charité University Medicine Berlin, Charitéplatz 1, Berlin 10117, Germany
| |
Collapse
|
12
|
Fang YL, Li N, Zhi XF, Zheng J, Liu Y, Pu LJ, Gu CY, Shu JB, Cai CQ. Discovery of specific mutations in spinal muscular atrophy patients by next-generation sequencing. Neurol Sci 2020; 42:1827-1833. [PMID: 32895776 DOI: 10.1007/s10072-020-04697-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/28/2020] [Indexed: 12/28/2022]
Abstract
Spinal muscular atrophy (SMA) is a type of autosomal recessive genetic disease, which seriously threatens the health and lives of children and adolescents. We attempted to find some genes and mutations related to the onset of SMA. Eighty-three whole-blood samples were collected from 28 core families, including 28 probands with clinically suspected SMA (20 SMA patients, 5 non-SMA children, and 3 patients with unknown etiology) and their parents. The multiplex ligation probe amplification (MLPA) was performed for preliminary diagnosis. The high-throughput sequencing technology was used to conduct the whole-exome sequencing analysis. We analyzed the mutations in adjacent genes of SMN1 gene and the unique mutations that only occurred in SMA patients. According to the MLPA results, 20 probands were regarded as experimental group and 5 non-SMA children as control group. A total of 10 mutations were identified in the adjacent genes of SMN1 gene. GUSBP1 g.[69515863G>A], GUSBP1 g.[69515870C>T], and SMA4 g.[69515738C>A] were the top three most frequent sites. SMA4 g.[69515726A>G] and OCLN c.[818G>T] have not been reported in the existing relevant researches. Seventeen point mutations in the DYNC1H1 gene were only recognized in SMA children, and the top two most common mutations were c.[2869-34A>T] and c.[345-89A>G]; c.[7473+105C>T] was the splicing mutation that might change the mRNA splicing site. The mutations of SMA4 g.[69515726A>G], OCLN c.[818G>T], DYNC1H1 c.[2869-34A>T], DYNC1H1 c.[345-89A>G], and DYNC1H1 c.[7473+105C>T] in the adjacent genes of SMN1 gene and other genes might be related to the onset of SMA.
Collapse
Affiliation(s)
- Yu-Lian Fang
- Institute of Pediatrics, Tianjin Children's Hospital, 238 Longyan Road, Beichen District, Tianjin, 300134, China
| | - Na Li
- Department of Neonatology, The Pediatric Clinical College, Tianjin Medical University, Tianjin, 300134, China.,Department of Neonatology, Tianjin Children's Hospital, Tianjin, 300134, China
| | - Xiu-Fang Zhi
- Graduate School, Tianjin Medical University, Tianjin, 300070, China
| | - Jie Zheng
- Graduate School, Tianjin Medical University, Tianjin, 300070, China
| | - Yang Liu
- Department of Neonatology, The Pediatric Clinical College, Tianjin Medical University, Tianjin, 300134, China.,Department of Neonatology, Tianjin Children's Hospital, Tianjin, 300134, China
| | - Lin-Jie Pu
- Graduate School, Tianjin Medical University, Tianjin, 300070, China
| | - Chun-Yu Gu
- Graduate School, Tianjin Medical University, Tianjin, 300070, China
| | - Jian-Bo Shu
- Institute of Pediatrics, Tianjin Children's Hospital, 238 Longyan Road, Beichen District, Tianjin, 300134, China. .,Tianjin Key Laboratory of Birth Defects for Prevention and Treatment, Tianjin, 300134, China.
| | - Chun-Quan Cai
- Institute of Pediatrics, Tianjin Children's Hospital, 238 Longyan Road, Beichen District, Tianjin, 300134, China. .,Tianjin Key Laboratory of Birth Defects for Prevention and Treatment, Tianjin, 300134, China. .,Department of Neurosurgery, Tianjin Children's Hospital, Tianjin, 300134, China.
| |
Collapse
|
13
|
Adami R, Bottai D. Spinal Muscular Atrophy Modeling and Treatment Advances by Induced Pluripotent Stem Cells Studies. Stem Cell Rev Rep 2020; 15:795-813. [PMID: 31863335 DOI: 10.1007/s12015-019-09910-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Spinal Muscular Atrophy (SMA) is a neurodegenerative disease characterized by specific and predominantly lower motor neuron (MN) loss. SMA is the main reason for infant death, while about one in 40 children born is a healthy carrier. SMA is caused by decreased levels of production of a ubiquitously expressed gene: the survival motor neuron (SMN). All SMA patients present mutations of the telomeric SMN1 gene, but many copies of a centromeric, partially functional paralog gene, SMN2, can somewhat compensate for the SMN1 deficiency, scaling inversely with phenotypic harshness. Because the study of neural tissue in and from patients presents too many challenges and is very often not feasible; the use of animal models, such as the mouse, had a pivotal impact in our understanding of SMA pathology but could not portray totally satisfactorily the elaborate regulatory mechanisms that are present in higher animals, particularly in humans. And while recent therapeutic achievements have been substantial, especially for very young infants, some issues should be considered for the treatment of older patients. An alternative way to study SMA, and other neurological pathologies, is the use of induced pluripotent stem cells (iPSCs) derived from patients. In this work, we will present a wide analysis of the uses of iPSCs in SMA pathology, starting from basic science to their possible roles as therapeutic tools.
Collapse
Affiliation(s)
- Raffaella Adami
- Department of Health Sciences, University of Milan, via A. di Rudinì 8, 20142, Milan, Italy
| | - Daniele Bottai
- Department of Health Sciences, University of Milan, via A. di Rudinì 8, 20142, Milan, Italy.
| |
Collapse
|
14
|
Therapeutic potential of stem cells for treatment of neurodegenerative diseases. Biotechnol Lett 2020; 42:1073-1101. [DOI: 10.1007/s10529-020-02886-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 04/05/2020] [Indexed: 12/13/2022]
|
15
|
Pera MC, Coratti G, Berti B, D’Amico A, Sframeli M, Albamonte E, de Sanctis R, Messina S, Catteruccia M, Brigati G, Antonaci L, Lucibello S, Bruno C, Sansone VA, Bertini E, Tiziano D, Pane M, Mercuri E. Diagnostic journey in Spinal Muscular Atrophy: Is it still an odyssey? PLoS One 2020; 15:e0230677. [PMID: 32203538 PMCID: PMC7089564 DOI: 10.1371/journal.pone.0230677] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 03/05/2020] [Indexed: 11/24/2022] Open
Abstract
Background The advent of new therapies has increased the need to achieve early diagnosis in Spinal Muscular Atrophy (SMA). The aim of the present study was to define the age of diagnosis in the three main types of SMA with pediatric-onset and the timing between the recognition of clinical signs and confirmed genetic diagnosis. Methods All patients with a confirmed diagnosis of type I, II, III SMA followed in 5 Italian centers were included in this study, assessing age at symptoms onset, presenting sign or symptom, age at diagnosis, interval between clinical onset and diagnosis and type of medical investigations conducted in order to obtain the diagnosis. Results The cohort included 480 patients, 191 affected by SMA type I, 210 by type II and 79 by type III. The mean age at diagnosis was 4.70 months (SD ±2.82) in type I, 15.6 months (SD±5.88) in type II, and 4.34 years (SD±4.01) in type III. The mean time between symptom onset and diagnosis was 1.94 months (SD±1.84) in type I, 5.28 months (SD±4.68) in type II and 16.8 months (SD±18.72) in type III. Conclusions Our results suggest that despite improved care recommendations there is still a marked diagnostic delay, especially in type III. At the time new therapies are becoming available more attention should be devoted to reducing such delay as there is consistent evidence of the benefit of early treatment.
Collapse
Affiliation(s)
| | - Giorgia Coratti
- Pediatric Neurology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Beatrice Berti
- Centro Clinico Nemo, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | - Adele D’Amico
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, IRCCS Bambino Gesù Children's Hospital, Rome, Italy
| | - Maria Sframeli
- Department of Neurosciences, and Centro Clinico Nemo Sud, University of Messina, Messina, Italy
| | - Emilio Albamonte
- Neurorehabilitation Unit, Neuromuscular Omnicentre Clinical Center, Niguarda Hospital, University of Milan, Milan, Italy
| | - Roberto de Sanctis
- Centro Clinico Nemo, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | - Sonia Messina
- Department of Neurosciences, and Centro Clinico Nemo Sud, University of Messina, Messina, Italy
| | - Michela Catteruccia
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, IRCCS Bambino Gesù Children's Hospital, Rome, Italy
| | - Giorgia Brigati
- Center of Experimental and Translational Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Laura Antonaci
- Pediatric Neurology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Simona Lucibello
- Pediatric Neurology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Claudio Bruno
- Center of Experimental and Translational Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Valeria A. Sansone
- Neurorehabilitation Unit, Neuromuscular Omnicentre Clinical Center, Niguarda Hospital, University of Milan, Milan, Italy
| | - Enrico Bertini
- Department of Neurosciences, Unit of Neuromuscular and Neurodegenerative Disorders, IRCCS Bambino Gesù Children's Hospital, Rome, Italy
| | - Danilo Tiziano
- Institute of Genomic Medicine, Università Cattolica del Sacro Cuore Fondazione, Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | - Marika Pane
- Centro Clinico Nemo, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | - Eugenio Mercuri
- Pediatric Neurology, Università Cattolica del Sacro Cuore, Rome, Italy
- Centro Clinico Nemo, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
- * E-mail:
| |
Collapse
|
16
|
Wadman RI, van der Pol WL, Bosboom WMJ, Asselman F, van den Berg LH, Iannaccone ST, Vrancken AFJE. Drug treatment for spinal muscular atrophy types II and III. Cochrane Database Syst Rev 2020; 1:CD006282. [PMID: 32006461 PMCID: PMC6995983 DOI: 10.1002/14651858.cd006282.pub5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by a homozygous deletion of the survival motor neuron 1 (SMN1) gene on chromosome 5, or a heterozygous deletion in combination with a (point) mutation in the second SMN1 allele. This results in degeneration of anterior horn cells, which leads to progressive muscle weakness. Children with SMA type II do not develop the ability to walk without support and have a shortened life expectancy, whereas children with SMA type III develop the ability to walk and have a normal life expectancy. This is an update of a review first published in 2009 and previously updated in 2011. OBJECTIVES To evaluate if drug treatment is able to slow or arrest the disease progression of SMA types II and III, and to assess if such therapy can be given safely. SEARCH METHODS We searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, and ISI Web of Science conference proceedings in October 2018. In October 2018, we also searched two trials registries to identify unpublished trials. SELECTION CRITERIA We sought all randomised or quasi-randomised trials that examined the efficacy of drug treatment for SMA types II and III. Participants had to fulfil the clinical criteria and have a homozygous deletion or hemizygous deletion in combination with a point mutation in the second allele of the SMN1 gene (5q11.2-13.2) confirmed by genetic analysis. The primary outcome measure was change in disability score within one year after the onset of treatment. Secondary outcome measures within one year after the onset of treatment were change in muscle strength, ability to stand or walk, change in quality of life, time from the start of treatment until death or full-time ventilation and adverse events attributable to treatment during the trial period. Treatment strategies involving SMN1-replacement with viral vectors are out of the scope of this review, but a summary is given in Appendix 1. Drug treatment for SMA type I is the topic of a separate Cochrane Review. DATA COLLECTION AND ANALYSIS We followed standard Cochrane methodology. MAIN RESULTS The review authors found 10 randomised, placebo-controlled trials of treatments for SMA types II and III for inclusion in this review, with 717 participants. We added four of the trials at this update. The trials investigated creatine (55 participants), gabapentin (84 participants), hydroxyurea (57 participants), nusinersen (126 participants), olesoxime (165 participants), phenylbutyrate (107 participants), somatotropin (20 participants), thyrotropin-releasing hormone (TRH) (nine participants), valproic acid (33 participants), and combination therapy with valproic acid and acetyl-L-carnitine (ALC) (61 participants). Treatment duration was from three to 24 months. None of the studies investigated the same treatment and none was completely free of bias. All studies had adequate blinding, sequence generation and reporting of primary outcomes. Based on moderate-certainty evidence, intrathecal nusinersen improved motor function (disability) in children with SMA type II, with a 3.7-point improvement in the nusinersen group on the Hammersmith Functional Motor Scale Expanded (HFMSE; range of possible scores 0 to 66), compared to a 1.9-point decline on the HFMSE in the sham procedure group (P < 0.01; n = 126). On all motor function scales used, higher scores indicate better function. Based on moderate-certainty evidence from two studies, the following interventions had no clinically important effect on motor function scores in SMA types II or III (or both) in comparison to placebo: creatine (median change 1 higher, 95% confidence interval (CI) -1 to 2; on the Gross Motor Function Measure (GMFM), scale 0 to 264; n = 40); and combination therapy with valproic acid and carnitine (mean difference (MD) 0.64, 95% CI -1.1 to 2.38; on the Modified Hammersmith Functional Motor Scale (MHFMS), scale 0 to 40; n = 61). Based on low-certainty evidence from other single studies, the following interventions had no clinically important effect on motor function scores in SMA types II or III (or both) in comparison to placebo: gabapentin (median change 0 in the gabapentin group and -2 in the placebo group on the SMA Functional Rating Scale (SMAFRS), scale 0 to 50; n = 66); hydroxyurea (MD -1.88, 95% CI -3.89 to 0.13 on the GMFM, scale 0 to 264; n = 57), phenylbutyrate (MD -0.13, 95% CI -0.84 to 0.58 on the Hammersmith Functional Motor Scale (HFMS) scale 0 to 40; n = 90) and monotherapy of valproic acid (MD 0.06, 95% CI -1.32 to 1.44 on SMAFRS, scale 0 to 50; n = 31). Very low-certainty evidence suggested that the following interventions had little or no effect on motor function: olesoxime (MD 2, 95% -0.25 to 4.25 on the Motor Function Measure (MFM) D1 + D2, scale 0 to 75; n = 160) and somatotropin (median change at 3 months 0.25 higher, 95% CI -1 to 2.5 on the HFMSE, scale 0 to 66; n = 19). One small TRH trial did not report effects on motor function and the certainty of evidence for other outcomes from this trial were low or very low. Results of nine completed trials investigating 4-aminopyridine, acetyl-L-carnitine, CK-2127107, hydroxyurea, pyridostigmine, riluzole, RO6885247/RG7800, salbutamol and valproic acid were awaited and not available for analysis at the time of writing. Various trials and studies investigating treatment strategies other than nusinersen (e.g. SMN2-augmentation by small molecules), are currently ongoing. AUTHORS' CONCLUSIONS Nusinersen improves motor function in SMA type II, based on moderate-certainty evidence. Creatine, gabapentin, hydroxyurea, phenylbutyrate, valproic acid and the combination of valproic acid and ALC probably have no clinically important effect on motor function in SMA types II or III (or both) based on low-certainty evidence, and olesoxime and somatropin may also have little to no clinically important effect but evidence was of very low-certainty. One trial of TRH did not measure motor function.
Collapse
Affiliation(s)
- Renske I Wadman
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - W Ludo van der Pol
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Wendy MJ Bosboom
- Onze Lieve Vrouwe Gasthuis locatie WestDepartment of NeurologyAmsterdamNetherlands
| | - Fay‐Lynn Asselman
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Leonard H van den Berg
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Susan T Iannaccone
- University of Texas Southwestern Medical CenterDepartment of Pediatrics5323 Harry Hines BoulevardDallasTexasUSA75390
| | - Alexander FJE Vrancken
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | | |
Collapse
|
17
|
Wadman RI, van der Pol WL, Bosboom WMJ, Asselman F, van den Berg LH, Iannaccone ST, Vrancken AFJE. Drug treatment for spinal muscular atrophy type I. Cochrane Database Syst Rev 2019; 12:CD006281. [PMID: 31825542 PMCID: PMC6905354 DOI: 10.1002/14651858.cd006281.pub5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by a homozygous deletion of the survival motor neuron 1 (SMN1) gene on chromosome 5, or a heterozygous deletion in combination with a point mutation in the second SMN1 allele. This results in degeneration of anterior horn cells, which leads to progressive muscle weakness. By definition, children with SMA type I are never able to sit without support and usually die or become ventilator dependent before the age of two years. There have until very recently been no drug treatments to influence the course of SMA. We undertook this updated review to evaluate new evidence on emerging treatments for SMA type I. The review was first published in 2009 and previously updated in 2011. OBJECTIVES To assess the efficacy and safety of any drug therapy designed to slow or arrest progression of spinal muscular atrophy (SMA) type I. SEARCH METHODS We searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, and ISI Web of Science conference proceedings in October 2018. We also searched two trials registries to identify unpublished trials (October 2018). SELECTION CRITERIA We sought all randomised controlled trials (RCTs) or quasi-RCTs that examined the efficacy of drug treatment for SMA type I. Included participants had to fulfil clinical criteria and have a genetically confirmed deletion or mutation of the SMN1 gene (5q11.2-13.2). The primary outcome measure was age at death or full-time ventilation. Secondary outcome measures were acquisition of motor milestones, i.e. head control, rolling, sitting or standing, motor milestone response on disability scores within one year after the onset of treatment, and adverse events and serious adverse events attributable to treatment during the trial period. Treatment strategies involving SMN1 gene replacement with viral vectors are out of the scope of this review. DATA COLLECTION AND ANALYSIS We followed standard Cochrane methodology. MAIN RESULTS We identified two RCTs: one trial of intrathecal nusinersen in comparison to a sham (control) procedure in 121 randomised infants with SMA type I, which was newly included at this update, and one small trial comparing riluzole treatment to placebo in 10 children with SMA type I. The RCT of intrathecally-injected nusinersen was stopped early for efficacy (based on a predefined Hammersmith Infant Neurological Examination-Section 2 (HINE-2) response). At the interim analyses after 183 days of treatment, 41% (21/51) of nusinersen-treated infants showed a predefined improvement on HINE-2, compared to 0% (0/27) of participants in the control group. This trial was largely at low risk of bias. Final analyses (ranging from 6 months to 13 months of treatment), showed that fewer participants died or required full-time ventilation (defined as more than 16 hours daily for 21 days or more) in the nusinersen-treated group than the control group (hazard ratio (HR) 0.53, 95% confidence interval (CI) 0.32 to 0.89; N = 121; a 47% lower risk; moderate-certainty evidence). A proportion of infants in the nusinersen group and none of 37 infants in the control group achieved motor milestones: 37/73 nusinersen-treated infants (51%) achieved a motor milestone response on HINE-2 (risk ratio (RR) 38.51, 95% CI 2.43 to 610.14; N = 110; moderate-certainty evidence); 16/73 achieved head control (RR 16.95, 95% CI 1.04 to 274.84; moderate-certainty evidence); 6/73 achieved independent sitting (RR 6.68, 95% CI 0.39 to 115.38; moderate-certainty evidence); 7/73 achieved rolling over (RR 7.70, 95% CI 0.45 to 131.29); and 1/73 achieved standing (RR 1.54, 95% CI 0.06 to 36.92; moderate-certainty evidence). Seventy-one per cent of nusinersen-treated infants versus 3% of infants in the control group were responders on the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) measure of motor disability (RR 26.36, 95% CI 3.79 to 183.18; N = 110; moderate-certainty evidence). Adverse events and serious adverse events occurred in the majority of infants but were no more frequent in the nusinersen-treated group than the control group (RR 0.99, 95% CI 0.92 to 1.05 and RR 0.70, 95% CI 0.55 to 0.89, respectively; N = 121; moderate-certainty evidence). In the riluzole trial, three of seven children treated with riluzole were still alive at the ages of 30, 48, and 64 months, whereas all three children in the placebo group died. None of the children in the riluzole or placebo group developed the ability to sit, which was the only milestone reported. There were no adverse effects. The certainty of the evidence for all measured outcomes from this study was very low, because the study was too small to detect or rule out an effect, and had serious limitations, including baseline differences. This trial was stopped prematurely because the pharmaceutical company withdrew funding. Various trials and studies investigating treatment strategies other than nusinersen, such as SMN2 augmentation by small molecules, are ongoing. AUTHORS' CONCLUSIONS Based on the very limited evidence currently available regarding drug treatments for SMA type 1, intrathecal nusinersen probably prolongs ventilation-free and overall survival in infants with SMA type I. It is also probable that a greater proportion of infants treated with nusinersen than with a sham procedure achieve motor milestones and can be classed as responders to treatment on clinical assessments (HINE-2 and CHOP INTEND). The proportion of children experiencing adverse events and serious adverse events on nusinersen is no higher with nusinersen treatment than with a sham procedure, based on evidence of moderate certainty. It is uncertain whether riluzole has any effect in patients with SMA type I, based on the limited available evidence. Future trials could provide more high-certainty, longer-term evidence to confirm this result, or focus on comparing new treatments to nusinersen or evaluate them as an add-on therapy to nusinersen.
Collapse
Affiliation(s)
- Renske I Wadman
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - W Ludo van der Pol
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Wendy MJ Bosboom
- Onze Lieve Vrouwe Gasthuis locatie WestDepartment of NeurologyAmsterdamNetherlands
| | - Fay‐Lynn Asselman
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Leonard H van den Berg
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | - Susan T Iannaccone
- University of Texas Southwestern Medical CenterDepartment of Pediatrics5323 Harry Hines BoulevardDallasTexasUSA75390
| | - Alexander FJE Vrancken
- University Medical Center Utrecht, Brain Center Rudolf MagnusDepartment of NeurologyHeidelberglaan 100UtrechtNetherlands3584 CX
| | | |
Collapse
|
18
|
Abstract
Autosomal-recessive proximal spinal muscular atrophy (Werdnig-Hoffmann, Kugelberg-Welander) is caused by mutation of the SMN1 gene, and the clinical severity correlates with the number of copies of a nearly identical gene, SMN2. The SMN protein plays a critical role in spliceosome assembly and may have other cellular functions, such as mRNA transport. Cell culture and animal models have helped to define the disease mechanism and to identify targets for therapeutic intervention. The main focus for developing treatment has been to increase SMN levels, and accomplishing this with small molecules, oligonucleotides, and gene replacement has been quite. An oligonucleotide, nusinersen, was recently approved for treatment in patients, and confirmatory studies of other agents are now under way.
Collapse
Affiliation(s)
- Eveline S Arnold
- Neurogenetics Branch, National Institutes of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Kenneth H Fischbeck
- Neurogenetics Branch, National Institutes of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States.
| |
Collapse
|
19
|
Critical period of neuromuscular development: Importance for a new treatment of SMA. Neuromuscul Disord 2018; 28:385-393. [DOI: 10.1016/j.nmd.2018.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/05/2018] [Accepted: 03/08/2018] [Indexed: 11/24/2022]
|
20
|
Takarada T, Ar Rochmah M, Harahap NIF, Shinohara M, Saito T, Saito K, Lai PS, Bouike Y, Takeshima Y, Awano H, Morioka I, Iijima K, Nishio H, Takeuchi A. SMA mutations in SMN Tudor and C-terminal domains destabilize the protein. Brain Dev 2017; 39:606-612. [PMID: 28366534 DOI: 10.1016/j.braindev.2017.03.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 02/27/2017] [Accepted: 03/03/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND AND PURPOSE Most spinal muscular atrophy (SMA) patients are homozygous for survival of motor neuron 1 gene (SMN1) deletion. However, some SMA patients carry an intragenic SMN1 mutation. Such patients provide a clue to understanding the function of the SMN protein and the role of each domain of the protein. We previously identified mutations in the Tudor domain and C-terminal region of the SMN protein in three Japanese SMA patients. To clarify the effect of these mutations on protein stability, we conducted expression assays of SMN with mutated domains. PATIENTS AND METHODS Patients A and B carried a mutation in SMN1 exon 3, which encodes a Tudor domain, c.275G>C (p.Trp92Ser). Patient C carried a mutation in SMN1 exon 6, which encodes a YG-box; c.819_820insT (p.Thr274Tyrfs). We constructed plasmid expression vectors containing wild-type and mutant SMN1 cDNAs. After transfection of HeLa cells with the expression plasmids, RNA and protein were isolated and analyzed by reverse-transcription PCR and western blot analysis. RESULTS The abundance of wild-type and mutant SMN1 transcripts in HeLa cells was almost the same. However, western blot analysis showed lower levels of mutant SMN proteins compared with wild-type SMN. In mutant SMN proteins, it is noteworthy that the level of the p.Thr274Tyrfs mutant was much reduced compared with that of the p.Trp92Ser mutant. CONCLUSIONS SMN mutations may affect the stability and levels of the protein.
Collapse
Affiliation(s)
- Toru Takarada
- Analytical Laboratory, Kobe Pharmaceutical University, Kobe, Japan
| | - Mawaddah Ar Rochmah
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Nur Imma Fatimah Harahap
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Masakazu Shinohara
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Toshio Saito
- Department of Neurology, Toneyama National Hospital, Osaka, Japan
| | - Kayoko Saito
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Poh San Lai
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | | | - Hiroyuki Awano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ichiro Morioka
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hisahide Nishio
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe, Japan; Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
| | - Atsuko Takeuchi
- Analytical Laboratory, Kobe Pharmaceutical University, Kobe, Japan
| |
Collapse
|
21
|
Su X, Kang PB, Russell JA, Simmons Z. Ethical issues in the evaluation of adults with suspected genetic neuromuscular disorders. Muscle Nerve 2016; 54:997-1006. [PMID: 27615030 DOI: 10.1002/mus.25400] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2016] [Indexed: 12/13/2022]
Abstract
Genetic testing is rapidly becoming an increasingly significant part of the diagnostic armamentarium of neuromuscular clinicians. Although technically easy to order, the results of such testing, whether positive or negative, have potentially enormous consequences for the individual tested and for family members. As a result, ethical considerations must be in the forefront of the physician's agenda when obtaining genetic testing. Informed consent is an important starting point for discussions between physicians and patients, but the counseling embedded in the informed consent process must be an ongoing part of subsequent interactions, including return of results and follow-up. Patient autonomy, including the right to know and right not-to-know results, must be respected. Considerations of capacity, physician beneficence and nonmaleficence, and privacy all play roles in the process. Muscle Nerve 54: 997-1006, 2016.
Collapse
Affiliation(s)
- Xiaowei Su
- Department of Neurology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Peter B Kang
- Division of Pediatric Neurology, University of Florida College of Medicine, Gainesville, Florida, USA
| | - James A Russell
- Section of Neurology, Lahey Hospital and Medical Center, Burlington, Massachusetts, USA
| | - Zachary Simmons
- Departments of Neurology and Humanities, Penn State Hershey Medical Center, 30 Hope Drive, Hershey, Pennsylvania, 17033, USA
| |
Collapse
|
22
|
Butchbach MER. Copy Number Variations in the Survival Motor Neuron Genes: Implications for Spinal Muscular Atrophy and Other Neurodegenerative Diseases. Front Mol Biosci 2016; 3:7. [PMID: 27014701 PMCID: PMC4785180 DOI: 10.3389/fmolb.2016.00007] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 02/25/2016] [Indexed: 12/11/2022] Open
Abstract
Proximal spinal muscular atrophy (SMA), a leading genetic cause of infant death worldwide, is an early-onset, autosomal recessive neurodegenerative disease characterized by the loss of spinal α-motor neurons. This loss of α-motor neurons is associated with muscle weakness and atrophy. SMA can be classified into five clinical grades based on age of onset and severity of the disease. Regardless of clinical grade, proximal SMA results from the loss or mutation of SMN1 (survival motor neuron 1) on chromosome 5q13. In humans a large tandem chromosomal duplication has lead to a second copy of the SMN gene locus known as SMN2. SMN2 is distinguishable from SMN1 by a single nucleotide difference that disrupts an exonic splice enhancer in exon 7. As a result, most of SMN2 mRNAs lack exon 7 (SMNΔ7) and produce a protein that is both unstable and less than fully functional. Although only 10–20% of the SMN2 gene product is fully functional, increased genomic copies of SMN2 inversely correlates with disease severity among individuals with SMA. Because SMN2 copy number influences disease severity in SMA, there is prognostic value in accurate measurement of SMN2 copy number from patients being evaluated for SMA. This prognostic value is especially important given that SMN2 copy number is now being used as an inclusion criterion for SMA clinical trials. In addition to SMA, copy number variations (CNVs) in the SMN genes can affect the clinical severity of other neurological disorders including amyotrophic lateral sclerosis (ALS) and progressive muscular atrophy (PMA). This review will discuss how SMN1 and SMN2 CNVs are detected and why accurate measurement of SMN1 and SMN2 copy numbers is relevant for SMA and other neurodegenerative diseases.
Collapse
Affiliation(s)
- Matthew E R Butchbach
- Center for Applied Clinical Genomics, Nemours Biomedical Research, Nemours Alfred I. duPont Hospital for ChildrenWilmington, DE, USA; Center for Pediatric Research, Nemours Biomedical Research, Nemours Alfred I. duPont Hospital for ChildrenWilmington, DE, USA; Department of Biological Sciences, University of DelawareNewark, DE, USA; Department of Pediatrics, Thomas Jefferson UniversityPhiladelphia, PA, USA
| |
Collapse
|
23
|
Phan HC, Taylor JL, Hannon H, Howell R. Newborn screening for spinal muscular atrophy: Anticipating an imminent need. Semin Perinatol 2015; 39:217-29. [PMID: 25979781 DOI: 10.1053/j.semperi.2015.03.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Spinal muscular atrophy (SMA) is the most common genetic cause of infant mortality. Children with type I SMA typically die by the age of 2 years. Recent progress in gene modification and other innovative therapies suggest that improved outcomes may soon be forthcoming. In animal models, therapeutic intervention initiated before the loss of motor neurons alters SMA phenotype and increases lifespan. Presently, supportive care including respiratory, nutritional, physiatry, and orthopedic management can ameliorate clinical symptoms and improve survival rates if SMA is diagnosed early in life. Newborn screening could help optimize these potential benefits. A recent report demonstrated that SMA detection can be multiplexed at minimal additional cost with the assay for severe combined immunodeficiency, already implemented by many newborn screening programs. The public health community should remain alert to the rapidly changing developments in early detection and treatment of SMA.
Collapse
Affiliation(s)
- Han C Phan
- Department of Pediatrics, Emory University, Atlanta, GA.
| | | | - Harry Hannon
- Newborn Screening Consensus Committee, Clinical and Laboratory Standards Institute (CLSI), Wayne, PA
| | - Rodney Howell
- Miller School of Medicine, University of Miami, Miami, FL
| |
Collapse
|
24
|
Yamamoto T, Sato H, Lai PS, Nurputra DK, Harahap NIF, Morikawa S, Nishimura N, Kurashige T, Ohshita T, Nakajima H, Yamada H, Nishida Y, Toda S, Takanashi JI, Takeuchi A, Tohyama Y, Kubo Y, Saito K, Takeshima Y, Matsuo M, Nishio H. Intragenic mutations in SMN1 may contribute more significantly to clinical severity than SMN2 copy numbers in some spinal muscular atrophy (SMA) patients. Brain Dev 2014; 36:914-20. [PMID: 24359787 DOI: 10.1016/j.braindev.2013.11.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 11/20/2013] [Accepted: 11/25/2013] [Indexed: 11/18/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder caused by deletion or intragenic mutation of SMN1. SMA is classified into several subtypes based on clinical severity. It has been reported that the copy number of SMN2, a highly homologous gene to SMN1, is associated with clinical severity among SMA patients with homozygous deletion of SMN1. The purpose of this study was to clarify the genotype-phenotype relationship among the patients without homozygous deletion of SMN1. METHODS We performed molecular genetic analyses of SMN1 and SMN2 in 112 Japanese patients diagnosed as having SMA based on the clinical findings. For the patients retaining SMN1, the PCR or RT-PCR products of SMN1 were sequenced to identify the mutation. RESULTS Out of the 112 patients, 106 patients were homozygous for deletion of SMN1, and six patients were compound heterozygous for deletion of one SMN1 allele and intragenic mutation in the retained SMN1 allele. Four intragenic mutations were identified in the six patients: p.Ala2Val, p.Trp92Ser, p.Thr274TyrfsX32 and p.Tyr277Cys. To the best of our knowledge, all mutations except p.Trp92Ser were novel mutations which had never been previously reported. According to our observation, clinical severity of the six patients was determined by the type and location of the mutation rather than SMN2 copy number. CONCLUSION SMN2 copy number is not always associated with clinical severity of SMA patients, especially SMA patients retaining one SMN1 allele.
Collapse
Affiliation(s)
- Tomoto Yamamoto
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan; Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hideyuki Sato
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Poh San Lai
- Department of Paediatrics, Yong Loo Lin School of Medicine, NUHS, National University of Singapore, Singapore
| | - Dian Kesumapramudya Nurputra
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Nur Imma Fatimah Harahap
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Satoru Morikawa
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan; Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Noriyuki Nishimura
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan; Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takashi Kurashige
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, Hiroshima, Japan
| | - Tomohiko Ohshita
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University, Graduate School of Biomedical and Health Sciences, Hiroshima, Japan
| | - Hideki Nakajima
- Department of Clinical Neuroscience and Neurology, Nagasaki University Graduate School of Biomedical Science, Nagasaki, Japan
| | - Hiroyuki Yamada
- Department of Pediatrics, Hyogo Prefectural Tsukaguchi Hospital, Amagasaki, Hyogo, Japan
| | - Yoshinobu Nishida
- Department of Pediatrics, Hyogo Prefectural Tsukaguchi Hospital, Amagasaki, Hyogo, Japan
| | - Soichiro Toda
- Department of Pediatrics, Kameda Medical Center, Kamogawa, Chiba, Japan
| | | | | | - Yumi Tohyama
- Faculty of Pharmaceutical Sciences, Himeji Dokkyo University, Himeji, Japan
| | - Yuji Kubo
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Kayoko Saito
- Institute of Medical Genetics, Tokyo Women's Medical University, Tokyo, Japan
| | - Yasuhiro Takeshima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Masafumi Matsuo
- Department of Medical Rehabilitation, Kobe Gakuin University, Kobe, Japan
| | - Hisahide Nishio
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan; Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
| |
Collapse
|
25
|
Pozzobon M, Franzin C, Piccoli M, De Coppi P. Fetal stem cells and skeletal muscle regeneration: a therapeutic approach. Front Aging Neurosci 2014; 6:222. [PMID: 25221507 PMCID: PMC4145352 DOI: 10.3389/fnagi.2014.00222] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 08/05/2014] [Indexed: 12/13/2022] Open
Abstract
More than 40% of the body mass is represented by muscle tissue, which possesses the innate ability to regenerate after damage through the activation of muscle-specific stem cells, namely satellite cells. Muscle diseases, in particular chronic degenerative states of skeletal muscle such as dystrophies, lead to a perturbation of the regenerative process, which causes the premature exhaustion of satellite cell reservoir due to continuous cycles of degeneration/regeneration. Nowadays, the research is focused on different therapeutic approaches, ranging from gene and cell to pharmacological therapy, but still there is no definitive cure in particular for genetic muscle disease. Keeping this in mind, in this article, we will give special consideration to muscle diseases and the use of fetal derived stem cells as a new approach for therapy. Cells of fetal origin, from cord blood to placenta and amniotic fluid, can be easily obtained without ethical concern, expanded and differentiated in culture, and possess immune-modulatory properties. The in vivo approach in animal models can be helpful to study the mechanism underneath the operating principle of the stem cell reservoir, namely the niche, which holds great potential to understand the onset of muscle pathologies.
Collapse
Affiliation(s)
- Michela Pozzobon
- Fondazione Istituto di Ricerca Pediatrica Città della Speranza , Padova , Italy
| | - Chiara Franzin
- Fondazione Istituto di Ricerca Pediatrica Città della Speranza , Padova , Italy
| | - Martina Piccoli
- Fondazione Istituto di Ricerca Pediatrica Città della Speranza , Padova , Italy
| | - Paolo De Coppi
- UCL Institute of Child Health and Great Ormond Street Hospital , London , UK
| |
Collapse
|
26
|
Sedghi M, Behnam M, Fazel E, Salehi M, Ganji H, Meamar R, Hosseinzadeh M, Nouri N. Genotype-phenotype correlation of survival motor neuron and neuronal apoptosis inhibitory protein genes in spinal muscular atrophy patients from Iran. Adv Biomed Res 2014; 3:74. [PMID: 24627882 PMCID: PMC3950840 DOI: 10.4103/2277-9175.125872] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 12/19/2012] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Proximal spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by symmetrical proximal muscle weakness and atrophy. According to the severity of the disease and the age of onset, SMA can be divided into three groups. The survival motor neuron (SMN) gene that is located on 5q13 is identified as the disease determining gene. Another gene in this region is neuronal apoptosis inhibitory protein (NAIP), and its functional role in the pathogenesis of SMA has not been fully elucidated. Here, we investigated the correlation between deletions in SMN and NAIP genes with clinical features of SMA patients. MATERIALS AND METHODS In the current study, 71 unrelated Iranian patients were investigated for the detection of deletions in SMN1 and NAIP genes. Polymerase chain reaction (PCR) was used to detect the deletions of exon 4 and 5 of the NAIP gene. Deletions in exon 7 and 8 of SMN1 gene were detected by RFLP-PCR with DraI and DdeI, respectively. RESULTS Our results showed that 51 patients have homozygous deletions in SMN1 and/or NAIP genes. Among these 51 patients, deletion in NAIP gene were found in 35 patients (65.7% of type I, 22.5% type II and 11.42% type III). CONCLUSION Defect in SMN1 gene plays a major role in manifesting of the disease and NAIP (4 and 5) gene acts as a modifying factor in severity of symptoms. Correlation between NAIP gene defect and severity of the disease is confirmed. However, the exact role of NAIP gene in SMA has yet to be fully clarified.
Collapse
Affiliation(s)
- Maryam Sedghi
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
- Pediatric Inherited Disease Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahdiyeh Behnam
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Esmat Fazel
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mansoor Salehi
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
- Department of Genetics and Molecular Biology, Medical School, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hamid Ganji
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Rokhsareh Meamar
- Neurosciences Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Majid Hosseinzadeh
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Nayereh Nouri
- Medical Genetics Laboratory, Alzahra University Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
- Pediatric Inherited Disease Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
27
|
Monani UR, De Vivo DC. Neurodegeneration in spinal muscular atrophy: from disease phenotype and animal models to therapeutic strategies and beyond. FUTURE NEUROLOGY 2014; 9:49-65. [PMID: 24648831 DOI: 10.2217/fnl.13.58] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Of the numerous inherited diseases known to afflict the pediatric population, spinal muscular atrophy (SMA) is among the most common. It has an incidence of approximately one in 10,000 newborns and a carrier frequency of one in 50. Despite its relatively high incidence, SMA remains somewhat obscure among the many neurodegenerative diseases that affect humans. Nevertheless, the last two decades have witnessed remarkable progress in our understanding of the pathology, underlying biology and especially the molecular genetics of SMA. This has led to a genuine expectation within the scientific community that a robust treatment will be available to patients before the end of the decade. The progress made in our understanding of SMA and, therefore, towards a viable therapy for affected individuals is in large measure a consequence of the simple yet fascinating genetics of the disease. Nevertheless, important questions remain. Addressing these questions promises not only to accelerate the march towards a cure for SMA, but also to uncover novel therapies for related neurodegenerative disorders. This review discusses our current understanding of SMA, considers the challenges ahead, describes existing treatment options and highlights state-of-the-art research being conducted as a means to a better, safer and more effective treatment for the disease.
Collapse
Affiliation(s)
- Umrao R Monani
- Department of Pathology & Cell Biology, 630 West 168th Street, Columbia University Medical Center, New York, NY 10032, USA ; Department of Neurology, 630 West 168th Street, Columbia University Medical Center, New York, NY 10032, USA ; Center for Motor Neuron Biology & Disease, 630 West 168th Street, Columbia University Medical Center, New York, NY 10032, USA
| | - Darryl C De Vivo
- Department of Neurology, 630 West 168th Street, Columbia University Medical Center, New York, NY 10032, USA ; Center for Motor Neuron Biology & Disease, 630 West 168th Street, Columbia University Medical Center, New York, NY 10032, USA ; Department of Pediatrics, 630 West 168th Street, Columbia University Medical Center, New York, NY 10032, USA
| |
Collapse
|
28
|
Nurputra DK, Lai PS, Harahap NIF, Morikawa S, Yamamoto T, Nishimura N, Kubo Y, Takeuchi A, Saito T, Takeshima Y, Tohyama Y, Tay SKH, Low PS, Saito K, Nishio H. Spinal muscular atrophy: from gene discovery to clinical trials. Ann Hum Genet 2013; 77:435-63. [PMID: 23879295 DOI: 10.1111/ahg.12031] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 04/26/2013] [Indexed: 12/25/2022]
Abstract
Spinal muscular atrophy (SMA) is a common neuromuscular disorder with autosomal recessive inheritance, resulting in the degeneration of motor neurons. The incidence of the disease has been estimated at 1 in 6000-10,000 newborns with a carrier frequency of 1 in 40-60. SMA is caused by mutations of the SMN1 gene, located on chromosome 5q13. The gene product, survival motor neuron (SMN) plays critical roles in a variety of cellular activities. SMN2, a homologue of SMN1, is retained in all SMA patients and generates low levels of SMN, but does not compensate for the mutated SMN1. Genetic analysis demonstrates the presence of homozygous deletion of SMN1 in most patients, and allows screening of heterozygous carriers in affected families. Considering high incidence of carrier frequency in SMA, population-wide newborn and carrier screening has been proposed. Although no effective treatment is currently available, some treatment strategies have already been developed based on the molecular pathophysiology of this disease. Current treatment strategies can be classified into three major groups: SMN2-targeting, SMN1-introduction, and non-SMN targeting. Here, we provide a comprehensive and up-to-date review integrating advances in molecular pathophysiology and diagnostic testing with therapeutic developments for this disease including promising candidates from recent clinical trials.
Collapse
Affiliation(s)
- Dian K Nurputra
- Department of Community Medicine and Social Health Care, Kobe University Graduate School of Medicine, Kobe, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Bottai D, Adami R. Spinal muscular atrophy: new findings for an old pathology. Brain Pathol 2013; 23:613-22. [PMID: 23750936 DOI: 10.1111/bpa.12071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2013] [Accepted: 05/24/2013] [Indexed: 12/15/2022] Open
Abstract
Understanding the events that are responsible for a disease is mandatory for setting up a therapeutic strategy. Although spinal muscular atrophy (SMA) is considered a rare neurodegenerative pathology, its impact in our society is really devastating as it strikes young people from birth onward, and it affects their families either emotionally or financially. Moreover, it requires intensive care for the children, and this diverts both parents and relatives from their occupations. Each neuron is very different from one another; therefore, in a neurodegenerative disease, the population of axons, synapses and cell bodies degenerate asynchronously, and subpopulations of neurons have different vulnerabilities. The knowledge of the sequence of events along the lengths of individual neurons is crucial to understand if each synapse degenerates before the corresponding axon, or if each axon degenerates before the corresponding cell body. Early degeneration of one neuronal compartment in disease often reflects molecular defects somewhere else. Up until now, SMA is considered mostly a lower motor neuron disease caused by the loss-of-function mutations in the SMN1 gene; here, we inspect other features that can be altered by this defect, such as the cross talk between muscle and motor neuron and the role of physical inactivity.
Collapse
Affiliation(s)
- Daniele Bottai
- Department of Science Health, University of Milan, Milano, Italy
| | | |
Collapse
|
30
|
Sifi Y, Sifi K, Boulefkhad A, Abadi N, Bouderda Z, Cheriet R, Magen M, Bonnefont JP, Munnich A, Benlatreche C, Hamri A. Clinical and Genetic Study of Algerian Patients with Spinal Muscular Atrophy. JOURNAL OF NEURODEGENERATIVE DISEASES 2013; 2013:903875. [PMID: 26317002 PMCID: PMC4437343 DOI: 10.1155/2013/903875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 02/12/2013] [Accepted: 02/18/2013] [Indexed: 11/23/2022]
Abstract
Spinal muscular atrophy (SMA) is the second most common lethal autosomal recessive disorder. It is divided into the acute Werdnig-Hoffmann disease (type I), the intermediate form (type II), the Kugelberg-Welander disease (type III), and the adult form (type IV). The gene involved in all four forms of SMA, the so-called survival motor neuron (SMN) gene, is duplicated, with a telomeric (tel SMN or SMN1) and a centromeric copy (cent SMN or SMN2). SMN1 is homozygously deleted in over 95% of SMA patients. Another candidate gene in SMA is the neuronal apoptosis inhibitory protein (NAIP) gene; it shows homozygous deletions in 45-67% of type I and 20-42% of type II/type III patients. Here we studied the SMN and NAIP genes in 92 Algerian SMA patients (20 type I, 16 type II, 53 type III, and 3 type IV) from 57 unrelated families, using a semiquantitative PCR approach. Homozygous deletions of SMN1 exons 7 and/or 8 were found in 75% of the families. Deletions of exon 4 and/or 5 of the NAIP gene were found in around 25%. Conversely, the quantitative analysis of SMN2 copies showed a significant correlation between SMN2 copy number and the type of SMA.
Collapse
Affiliation(s)
- Y. Sifi
- Service of Neurology CHU of Constantine, Algeria
- Laboratory of Biology and Molecular Genetics CHU and University of Constantine, Algeria
| | - K. Sifi
- Laboratory of Biology and Molecular Genetics CHU and University of Constantine, Algeria
- Laboratory of Biochemistry CHU of Constantine, Algeria
| | - A. Boulefkhad
- Service of Neurology CHU of Constantine, Algeria
- Laboratory of Biology and Molecular Genetics CHU and University of Constantine, Algeria
| | - N. Abadi
- Laboratory of Biology and Molecular Genetics CHU and University of Constantine, Algeria
- Laboratory of Biochemistry CHU of Constantine, Algeria
| | - Z. Bouderda
- Service of Pediatrics CHU de Constantine, Algeria
| | - R. Cheriet
- Service of Pediatrics CHU de Constantine, Algeria
| | - M. Magen
- Genetic Department of the Necker Hospital and Paris Descartes University, Paris, France
| | - J. P. Bonnefont
- Genetic Department of the Necker Hospital and Paris Descartes University, Paris, France
| | - A. Munnich
- Genetic Department of the Necker Hospital and Paris Descartes University, Paris, France
| | - C. Benlatreche
- Laboratory of Biology and Molecular Genetics CHU and University of Constantine, Algeria
- Laboratory of Biochemistry CHU of Constantine, Algeria
| | - A. Hamri
- Service of Neurology CHU of Constantine, Algeria
- Laboratory of Biochemistry CHU of Constantine, Algeria
| |
Collapse
|
31
|
Therapeutic strategies for the treatment of spinal muscular atrophy. Future Med Chem 2013; 4:1733-50. [PMID: 22924510 DOI: 10.4155/fmc.12.107] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Spinal muscular atrophy (SMA) is an inherited neurodegenerative disease that results in progressive dysfunction of motor neurons of the anterior horn of the spinal cord. SMA is caused by the loss of full-length protein expression from the survival of motor neuron 1 (SMN1) gene. The disease has a unique genetic profile as it is autosomal recessive for the loss of SMN1, but a nearly identical homolog, SMN2, acts as a disease modifier whose expression is inversely correlated to clinical severity. Targeted therapeutic approaches primarily focus on increasing the levels of full-length SMN protein, through either gene replacement or regulation of SMN2 expression. There is currently no US FDA approved treatment for SMA. This is an exciting time as multiple efforts from academic and industrial laboratories are reaching the preclinical and clinical testing stages.
Collapse
|
32
|
Wadman RI, Bosboom WMJ, van der Pol WL, van den Berg LH, Wokke JHJ, Iannaccone ST, Vrancken AFJE. Drug treatment for spinal muscular atrophy types II and III. Cochrane Database Syst Rev 2012:CD006282. [PMID: 22513940 DOI: 10.1002/14651858.cd006282.pub4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by degeneration of anterior horn cells, which leads to progressive muscle weakness. Children with SMA type II do not develop the ability to walk without support and have a shortened life expectancy, whereas children with SMA type III develop the ability to walk and have a normal life expectancy. There are no known efficacious drug treatments that influence the disease course of SMA. This is an update of a review first published in 2009. OBJECTIVES To evaluate whether drug treatment is able to slow or arrest the disease progression of SMA types II and III and to assess if such therapy can be given safely. Drug treatment for SMA type I is the topic of a separate updated Cochrane review. SEARCH METHODS We searched the Cochrane Neuromuscular Disease Group Specialized Register (8 March 2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), MEDLINE (January 1991 to February 2011), EMBASE (January 1991 to February 2011) and ISI Web of Knowledge (January 1991 to March 8 2011). We also searched clinicaltrials.gov to identify as yet unpublished trials (8 March 2011). SELECTION CRITERIA We sought all randomised or quasi-randomised trials that examined the efficacy of drug treatment for SMA types II and III. Participants had to fulfil the clinical criteria and have a deletion or mutation of the survival motor neuron 1 (SMN1) gene (5q11.2-13.2) that was confirmed by genetic analysis.The primary outcome measure was to be change in disability score within one year after the onset of treatment. Secondary outcome measures within one year after the onset of treatment were to be change in muscle strength, ability to stand or walk, change in quality of life, time from the start of treatment until death or full time ventilation and adverse events attributable to treatment during the trial period. DATA COLLECTION AND ANALYSIS Two authors independently reviewed and extracted data from all potentially relevant trials. Pooled relative risks and pooled standardised mean differences were to be calculated to assess treatment efficacy. Risk of bias was systematically analysed. MAIN RESULTS Six randomised placebo-controlled trials on treatment for SMA types II and III were found and included in the review: the four in the original review and two trials added in this update. The treatments were creatine (55 participants), phenylbutyrate (107 participants), gabapentin (84 participants), thyrotropin releasing hormone (9 participants), hydroxyurea (57 participants), and combination therapy with valproate and acetyl-L-carnitine (61 participants). None of these studies were completely free of bias. All studies had adequate blinding, sequence generation and reports of primary outcomes.None of the included trials showed any statistically significant effects on the outcome measures in participants with SMA types II and III. One participant died due to suffocation in the hydroxyurea trial and one participant died in the creatine trial. No participants in any of the other four trials died or reached the state of full time ventilation. Serious side effects were infrequent. AUTHORS' CONCLUSIONS There is no proven efficacious drug treatment for SMA types II and III.
Collapse
Affiliation(s)
- Renske I Wadman
- Department of Neurology, University Medical Center Utrecht, Utrecht, Netherlands.
| | | | | | | | | | | | | |
Collapse
|
33
|
Wadman RI, Bosboom WMJ, van der Pol WL, van den Berg LH, Wokke JHJ, Iannaccone ST, Vrancken AFFJE. Drug treatment for spinal muscular atrophy type I. Cochrane Database Syst Rev 2012:CD006281. [PMID: 22513939 DOI: 10.1002/14651858.cd006281.pub4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by degeneration of anterior horn cells of the spinal cord, which leads to progressive muscle weakness. Children with SMA type I will never be able to sit without support and usually die by the age of two years. There are no known efficacious drug treatments that influence the course of the disease. This is an update of a review first published in 2009. OBJECTIVES To evaluate whether drug treatment is able to slow or arrest the disease progression of SMA type I, and to assess if such therapy can be given safely. Drug treatment for SMA types II and III is the topic of a separate updated Cochrane review. SEARCH METHODS We searched the Cochrane Neuromuscular Disease Group Specialized Register (8 March 2011), CENTRAL (The Cochrane Library 2011, Issue 1), MEDLINE (January 1991 to February 2011), EMBASE (January 1991 to February 2011) and ISI Web of Knowledge (January 1991 to 8 March 2011). We searched the Clinical Trials Registry of the U.S. National Institute of Health (www.ClinicalTrials.gov) (8 March 2011) to identify additional trials that had not yet been published. SELECTION CRITERIA We sought all randomised or quasi-randomised trials that examined the efficacy of drug treatment for SMA type I. Participants had to fulfil the clinical criteria and have a deletion or mutation of the SMN1 gene (5q11.2-13.2) confirmed by genetic analysis.The primary outcome measure was time from birth until death or full time ventilation. Secondary outcome measures were development of rolling, sitting or standing within one year after the onset of treatment, and adverse events attributable to treatment during the trial period. DATA COLLECTION AND ANALYSIS Two authors (RW and AV) independently reviewed and extracted data from all potentially relevant trials. For included studies, pooled relative risks and standardised mean differences were to be calculated to assess treatment efficacy. MAIN RESULTS One small randomised controlled study comparing riluzole treatment to placebo for 10 SMA type 1 children was identified and included in the original review. No further trials were identified for the update in 2011. Regarding the primary outcome measure, three of seven children treated with riluzole were still alive at the ages of 30, 48 and 64 months, whereas all three children in the placebo group died; but the difference was not statistically significant. Regarding the secondary outcome measures, none of the children in the riluzole or placebo group developed the ability to roll, sit or stand, and no adverse effects were observed. For several reasons the overall quality of the study was low, mainly because the study was too small to detect an effect and because of baseline differences. Follow-up of the 10 included children was complete. AUTHORS' CONCLUSIONS No drug treatment for SMA type I has been proven to have significant efficacy.
Collapse
Affiliation(s)
- Renske I Wadman
- Department of Neurology, University Medical Center Utrecht, Utrecht, Netherlands.
| | | | | | | | | | | | | |
Collapse
|
34
|
Harahap ISK, Saito T, San LP, Sasaki N, Gunadi, Nurputra DKP, Yusoff S, Yamamoto T, Morikawa S, Nishimura N, Lee MJ, Takeshima Y, Matsuo M, Nishio H. Valproic acid increases SMN2 expression and modulates SF2/ASF and hnRNPA1 expression in SMA fibroblast cell lines. Brain Dev 2012; 34:213-22. [PMID: 21561730 DOI: 10.1016/j.braindev.2011.04.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 04/14/2011] [Accepted: 04/14/2011] [Indexed: 12/11/2022]
Abstract
Spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disorder that is caused by loss of the survival motor neuron gene, SMN1. SMA treatment strategies have focused on production of the SMN protein from the almost identical gene, SMN2. Valproic acid (VPA) is a histone deacetylase inhibitor that can increase SMN levels in some SMA cells or SMA patients through activation of SMN2 transcription or splicing correction of SMN2 exon 7. It remains to be clarified what concentration of VPA is required and by what mechanisms the SMN production from SMN2 is elicited. We observed that in two fibroblast cell lines from Japanese SMA patients, more than 1mM of VPA increased SMN2 expression at both the transcript and protein levels. VPA increased not only full-length (FL) transcript level but also exon 7-excluding (Δ7) transcript level in the cell lines and did not change the ratio of FL/Δ7, suggesting that SMN2 transcription was mainly activated. We also found that VPA modulated splicing factor expression: VPA increased the expression of splicing factor 2/alternative splicing factor (SF2/ASF) and decreased the expression of heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1). In conclusion, more than 1mM of VPA activated SMN2 transcription and modulated the expression of splicing factors in our SMA fibroblast cell lines.
Collapse
Affiliation(s)
- Indra Sari Kusuma Harahap
- Department of Community Medicine and Social Healthcare Science, Kobe University Graduate School of Medicine, Kobe, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Wadman RI, Bosboom WM, van den Berg LH, Wokke JH, Iannaccone ST, Vrancken AF. Drug treatment for spinal muscular atrophy type I. Cochrane Database Syst Rev 2011:CD006281. [PMID: 22161399 DOI: 10.1002/14651858.cd006281.pub3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by degeneration of anterior horn cells of the spinal cord, which leads to progressive muscle weakness. Children with SMA type I will never be able to sit without support and usually die by the age of two years. There are no known efficacious drug treatments that influence the course of the disease. This is an update of a review first published in 2009. OBJECTIVES To evaluate whether drug treatment is able to slow or arrest the disease progression of SMA type I, and to assess if such therapy can be given safely. Drug treatment for SMA types II and III is the topic of a separate updated Cochrane review. SEARCH METHODS We searched the Cochrane Neuromuscular Disease Group Specialized Register (8 March 2011), CENTRAL (The Cochrane Library 2011, Issue 1), MEDLINE (January 1991 to February 2011), EMBASE (January 1991 to February 2011) and ISI Web of Knowledge (January 1991 to 8 March 2011). We searched the Clinical Trials Registry of the U.S. National Institute of Health (www.ClinicalTrials.gov) (8 March 2011) to identify additional trials that had not yet been published. SELECTION CRITERIA We sought all randomised or quasi-randomised trials that examined the efficacy of drug treatment for SMA type I. Participants had to fulfil the clinical criteria and have a deletion or mutation of the SMN1 gene (5q11.2-13.2) confirmed by genetic analysis.The primary outcome measure was time from birth until death or full time ventilation. Secondary outcome measures were development of rolling, sitting or standing within one year after the onset of treatment, and adverse events attributable to treatment during the trial period. DATA COLLECTION AND ANALYSIS Two authors (RW and AV) independently reviewed and extracted data from all potentially relevant trials. For included studies, pooled relative risks and standardised mean differences were to be calculated to assess treatment efficacy. MAIN RESULTS One small randomised controlled study comparing riluzole treatment to placebo for 10 SMA type 1 children was identified and included in the original review. No further trials were identified for the update in 2011. Regarding the primary outcome measure, three of seven children treated with riluzole were still alive at the ages of 30, 48 and 64 months, whereas all three children in the placebo group died; but the difference was not statistically significant. Regarding the secondary outcome measures, none of the children in the riluzole or placebo group developed the ability to roll, sit or stand, and no adverse effects were observed. For several reasons the overall quality of the study was low, mainly because the study was too small to detect an effect and because of baseline differences. Follow-up of the 10 included children was complete. AUTHORS' CONCLUSIONS No drug treatment for SMA type I has been proven to have significant efficacy.
Collapse
Affiliation(s)
- Renske I Wadman
- Department of Neurology, University Medical Center Utrecht, Rudolf Magnus Institute for Neuroscience, Universiteitsweg 100, Utrecht, Netherlands, 3584 CG
| | | | | | | | | | | |
Collapse
|
36
|
Wadman RI, Bosboom WM, van den Berg LH, Wokke JH, Iannaccone ST, Vrancken AF. Drug treatment for spinal muscular atrophy types II and III. Cochrane Database Syst Rev 2011:CD006282. [PMID: 22161400 DOI: 10.1002/14651858.cd006282.pub3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by degeneration of anterior horn cells, which leads to progressive muscle weakness. Children with SMA type II do not develop the ability to walk without support and have a shortened life expectancy, whereas children with SMA type III develop the ability to walk and have a normal life expectancy. There are no known efficacious drug treatments that influence the disease course of SMA. This is an update of a review first published in 2009. OBJECTIVES To evaluate whether drug treatment is able to slow or arrest the disease progression of SMA types II and III and to assess if such therapy can be given safely. Drug treatment for SMA type I is the topic of a separate updated Cochrane review. SEARCH METHODS We searched the Cochrane Neuromuscular Disease Group Specialized Register (8 March 2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), MEDLINE (January 1991 to February 2011), EMBASE (January 1991 to February 2011) and ISI Web of Knowledge (January 1991 to March 8 2011). We also searched clinicaltrials.gov to identify as yet unpublished trials (8 March 2011). SELECTION CRITERIA We sought all randomised or quasi-randomised trials that examined the efficacy of drug treatment for SMA types II and III. Participants had to fulfil the clinical criteria and have a deletion or mutation of the survival motor neuron 1 (SMN1) gene (5q11.2-13.2) that was confirmed by genetic analysis.The primary outcome measure was to be change in disability score within one year after the onset of treatment. Secondary outcome measures within one year after the onset of treatment were to be change in muscle strength, ability to stand or walk, change in quality of life, time from the start of treatment until death or full time ventilation and adverse events attributable to treatment during the trial period. DATA COLLECTION AND ANALYSIS Two authors independently reviewed and extracted data from all potentially relevant trials. Pooled relative risks and pooled standardised mean differences were to be calculated to assess treatment efficacy. Risk of bias was systematically analysed. MAIN RESULTS Six randomised placebo-controlled trials on treatment for SMA types II and III were found and included in the review: the four in the original review and two trials added in this update. The treatments were creatine (55 participants), phenylbutyrate (107 participants), gabapentin (84 participants), thyrotropin releasing hormone (9 participants), hydroxyurea (57 participants), and combination therapy with valproate and acetyl-L-carnitine (61 participants). None of these studies were completely free of bias. All studies had adequate blinding, sequence generation and reports of primary outcomes.None of the included trials showed any statistically significant effects on the outcome measures in participants with SMA types II and III. One participant died due to suffocation in the hydroxyurea trial and one participant died in the creatine trial. No participants in any of the other four trials died or reached the state of full time ventilation. Serious side effects were infrequent. AUTHORS' CONCLUSIONS There is no proven efficacious drug treatment for SMA types II and III.
Collapse
Affiliation(s)
- Renske I Wadman
- Department of Neurology, University Medical Center Utrecht, Rudolf Magnus Institute for Neuroscience, Universiteitsweg 100, Utrecht, Netherlands, 3584 CG
| | | | | | | | | | | |
Collapse
|
37
|
Abstract
Spinal muscular atrophy (SMA), a potentially devastating disease marked by progressive weakness and muscle atrophy resulting from the dysfunction and loss of motor neurons of the spinal cord, has emerged in recent years as an attractive target for therapeutic intervention. Caused by a homozygous mutation to the Survival of Motor Neurons 1 (SMN1) gene on chromosome 5q, the severity of the clinical phenotype in SMA is modulated by the function of a related protein, Survival of Motor Neurons 2 (SMN2). SMN2 predominantly produces an unstable SMN transcript lacking exon 7; only about 10% of the transcription product produces a full-length, functional SMN protein. Several therapeutic strategies have targeted this gene with the goal of producing increased full-length SMN transcript, thereby modifying the underlying mechanism. Drugs that have increased SMN2 function, in vitro, are now explored for potential therapeutic benefit in this disease. Alternative approaches, including neuroprotective, muscle anabolic, gene and cell replacement strategies, also hold promise. The recent advances in preclinical research and the development of a wider range of animal models for SMA continue to provide cautious optimism that effective treatments for SMA will eventually emerge.
Collapse
Affiliation(s)
- Douglas M Sproule
- Division of Pediatric Neurosciences, Department of Neurology, SMA Clinical Research Center, Columbia University Medical Center, Harkness Pavilion, HP-514, 180 Fort Washington Avenue, New York, NY 10032-3791, USA.
| | | |
Collapse
|
38
|
Kaufmann P, McDermott MP, Darras BT, Finkel R, Kang P, Oskoui M, Constantinescu A, Sproule DM, Foley AR, Yang M, Tawil R, Chung W, Martens B, Montes J, O'Hagen J, Dunaway S, Flickinger JM, Quigley J, Riley S, Glanzman AM, Benton M, Ryan PA, Irvine C, Annis CL, Butler H, Caracciolo J, Montgomery M, Marra J, Koo B, De Vivo DC. Observational study of spinal muscular atrophy type 2 and 3: functional outcomes over 1 year. ACTA ACUST UNITED AC 2011; 68:779-86. [PMID: 21320981 DOI: 10.1001/archneurol.2010.373] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To characterize the short-term course of spinal muscular atrophy (SMA) in a genetically and clinically well-defined cohort of patients with SMA. DESIGN A comprehensive multicenter, longitudinal, observational study. SETTING The Pediatric Neuromuscular Clinical Research Network for SMA, a consortium of clinical investigators at 3 clinical sites. PARTICIPANTS Sixty-five participants with SMA types 2 and 3, aged 20 months to 45 years, were prospectively evaluated. INTERVENTION We collected demographic and medical history information and determined the SMN 2 copy number. MAIN OUTCOME MEASURES Clinical outcomes included measures of motor function (Gross Motor Function Measure and expanded Hammersmith Functional Motor Scale), pulmonary function (forced vital capacity), and muscle strength (myometry). Participants were evaluated every 2 months for the initial 6 months and every 3 months for the subsequent 6 months. We evaluated change over 12 months for all clinical outcomes and examined potential correlates of change over time including age, sex, SMA type, ambulatory status, SMN2 copy number, medication use, and baseline function. RESULTS There were no significant changes over 12 months in motor function, pulmonary function, and muscle strength measures. There was evidence of motor function gain in ambulatory patients, especially in those children younger than 5 years. Scoliosis surgery during the observation period led to a subsequent decline in motor function. CONCLUSIONS Our results confirm previous clinical reports suggesting that SMA types 2 and 3 represent chronic phenotypes that have relatively stable clinical courses. We did not detect any measurable clinical disease progression in SMA types 2 and 3 over 12 months, suggesting that clinical trials will have to be designed to measure improvement rather than stabilization of disease progression.
Collapse
Affiliation(s)
- Petra Kaufmann
- Department of Neurology, Columbia University, 710 W 168th St, 2nd Floor, New York, NY 10032, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Petit F, Cuisset JM, Rouaix-Emery N, Cancés C, Sablonnière B, Bieth E, Moerman A, Sukno S, Hardy N, Holder-Espinasse M, Manouvrier-Hanu S, Vallée L. Insights into genotype-phenotype correlations in spinal muscular atrophy: a retrospective study of 103 patients. Muscle Nerve 2011; 43:26-30. [PMID: 21171094 DOI: 10.1002/mus.21832] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive disorder associated with homozygous deletion of the survival motor neuron 1 gene (SMN1). Its centromeric copy gene, SMN2, is the major modifying factor. However, the genotype-phenotype correlation is incomplete and is therefore not useful in clinical practice. We studied a cohort of 103 patients in order to refine this correlation. In addition to standard disease severity data, we collected three additional criteria: age at death; brainstem involvement; and loss of ambulation. Gene dosage analysis was conducted by multiplex ligation-dependent probe amplification (MLPA). SMN2 copynumber was highly correlated with survival duration in SMA type I and ambulation conservation or loss in type III. Among SMA severity groups, it was not significantly different in cases with brainstem involvement. Although the SMN2 copynumber could provide prognostic indications, clinical discrepancies still exist among patients, suggesting the existence of unidentified modifying factors.
Collapse
Affiliation(s)
- Florence Petit
- Service de Génétique Clinique, CHU Hôpital Jeanne de Flandre, Lille, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Drug discovery and development for spinal muscular atrophy: lessons from screening approaches and future challenges for clinical development. Future Med Chem 2010; 2:1429-40. [DOI: 10.4155/fmc.10.228] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a progressive pediatric neuromuscular disease. Because disease severity is related to survival motor neuron (SMN) protein levels, increasing SMN production from the SMN2 gene has been a major SMA drug-discovery strategy. Cell-based assays using neuronal cell lines and cells from SMA patients have identified compounds that can increase SMN protein expression. Our experience of using such an assay signaled potential risks to be avoided through the use of appropriate secondary assays. In addition to the ‘SMN2’ approach, compensating for decreased SMN protein or neuroprotection are also potential SMA drug-discovery strategies. SMA clinical trials are now a reality; however, trial design in a slowly progressing rare disease such as SMA will present an interesting future challenge.
Collapse
|
41
|
Burlet P, Gigarel N, Magen M, Drunat S, Benachi A, Hesters L, Munnich A, Bonnefont JP, Steffann J. Single-sperm analysis for recurrence risk assessment of spinal muscular atrophy. Eur J Hum Genet 2010; 18:505-8. [PMID: 19904299 PMCID: PMC2987255 DOI: 10.1038/ejhg.2009.198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 09/10/2009] [Accepted: 09/11/2009] [Indexed: 11/09/2022] Open
Abstract
With the detection of a homozygous deletion of the survival motor neuron 1 gene (SMN1), prenatal and preimplantation genetic diagnosis (PGD) for spinal muscular atrophy has become feasible and widely applied. The finding of a de novo rearrangement, resulting in the loss of the SMN1 gene, reduces the recurrence risk from 25% to a lower percentage, the residual risk arising from recurrent de novo mutation or germline mosaicism. In a couple referred to our PGD center because their first child was affected with SMA, the male partner was shown to carry two SMN1 copies. An analysis of the SMN1 gene and two flanking markers was performed on 12 single spermatozoa, to determine whether the father carried a CIS duplication of the SMN1 gene on one chromosome and was a carrier, or if the deletion has occurred de novo. We showed that all spermatozoa that were carriers of the 'at-risk haplotype' were deleted for the SMN1 gene, confirming the carrier status of the father. We provide an original application of single germ cell studies to recessive disorders using coamplification of the gene and its linked markers. This efficient and easy procedure might be useful to elucidate complex genetic situations when samples from other family members are not available.
Collapse
Affiliation(s)
- Philippe Burlet
- Unité INSERM U781 Institut de Recherche Necker-Enfants Malades, service de génétique médicale, Hôpital Necker-Enfants Malades (Assistance Publique-Hôpitaux de Paris), Université Paris-Descartes, 75743 Paris Cedex 15, France.
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
The spinal muscular atrophy protein SMN affects Drosophila germline nuclear organization through the U body–P body pathway. Dev Biol 2009; 332:142-55. [DOI: 10.1016/j.ydbio.2009.05.553] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 05/15/2009] [Accepted: 05/15/2009] [Indexed: 11/19/2022]
|
43
|
Omrani O, Bonyadi M, Barzgar M. Molecular analysis of the SMN and NAIP genes in Iranian spinal muscular atrophy patients. Pediatr Int 2009; 51:193-6. [PMID: 19405914 DOI: 10.1111/j.1442-200x.2008.02665.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder characterized by degeneration of spinal cord anterior horn cells, leading to muscular atrophy. SMA is clinically classified into three subgroups based on the age of onset and severity. The majority of patients with SMA have homozygous deletions of exons 7 and 8 of the survival motor neuron (SMN) gene. The purpose of the present study was to determine the frequency of SMN and neuronal apoptosis inhibitory protein (NAIP) gene deletions in Iranian SMA patients. Experience in prenatal diagnosis of SMA in this population is also reported. METHODS To study the frequency of deletions of SMN and NAIP genes in an Iranian sample group, 75 unrelated SMA patients (54 type I, eight type II and 13 type III) were analyzed according to the methods described by van der Steege et al and Roy et al. RESULTS Homozygous deletion of SMN1 exons 7 and/or 8 were identified in 68 out of 75 patients (90%). Deletion of exon 5 of the NAIP gene was found in 40/54 of type I, 2/8 of type II and 1/13 of type III patients. CONCLUSIONS Deletion of the SMN1 gene is a major cause of SMA in Iran, and NAIP gene deletions were common in the present patients with type I SMA. Also, the incidence of NAIP deletion is higher in more severe SMA.
Collapse
Affiliation(s)
- Omid Omrani
- Department of Genetics, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
| | | | | |
Collapse
|
44
|
Mannaa MM, Kalra M, Wong B, Cohen AP, Amin RS. Survival probabilities of patients with childhood spinal muscle atrophy. J Clin Neuromuscul Dis 2009; 10:85-89. [PMID: 19258855 DOI: 10.1097/cnd.0b013e318190310f] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE Medical and technological advances over the past 2 decades have resulted in improved patient care for children with spinal muscular atrophy (SMA). The objective of the present study was to describe changes in the life expectancy of pediatric patients with SMA over time and to compare these findings with previously reported survival patterns. METHODS Medical records of all patients diagnosed with SMA over a 16-year period (1989-2005) at Cincinnati Children's Hospital Medical Center were reviewed. Data pertaining to date of birth, type of SMA, medical and surgical interventions, pulmonary complications, and date of death were obtained. RESULTS Kaplan-Meier survival analyses showed a significant improvement in survival probabilities in the severest form of SMA. CONCLUSIONS We found a positive trend in the survival of patients with severe SMA. Although we cannot attribute this trend to any single factor, it is likely that advances in pulmonary care and aggressive nutritional support have played a significant role.
Collapse
Affiliation(s)
- Mohannad M Mannaa
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | | | | | | | | |
Collapse
|
45
|
Bosboom WMJ, Vrancken AFJE, van den Berg LH, Wokke JHJ, Iannaccone ST. Drug treatment for spinal muscular atrophy types II and III. Cochrane Database Syst Rev 2009:CD006282. [PMID: 19160275 DOI: 10.1002/14651858.cd006282.pub2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by degeneration of anterior horn cells, which leads to progressive muscle weakness. Children with SMA type II do not develop the ability to walk without support and have a shortened life expectancy, whereas children with SMA type III develop the ability to walk and have a normal life expectancy. There are no known efficacious drug treatments that influence the disease course of SMA. OBJECTIVES To evaluate if drug treatment is able to slow or arrest the disease progression of SMA type II and III, and to assess if such therapy can be given safely. Drug treatment for SMA type I will be the topic of a separate Cochrane review. SEARCH STRATEGY We searched the Cochrane Neuromuscular Disease Group Trials Register (September 30 2008), The Cochrane Library (Issue 3, 2008), MEDLINE (January 1966 to June 2008), EMBASE (January 1980 to June 2008), ISI (January 1988 to June 2008), and ACP Journal Club (January 1991 to June 2008). SELECTION CRITERIA We sought all randomized or quasi-randomized trials that examined the efficacy of drug treatment for SMA type II and III. Participants had to fulfil the clinical criteria and, in studies including genetic analysis to confirm the diagnosis, have a deletion or mutation of the SMN1 gene (5q11.2-13.2)The primary outcome measure was to be change in disability score within one year after the onset of treatment. Secondary outcome measures within one year after the onset of treatment were to be change in muscle strength, ability to stand or walk, change in quality of life, time from the start of treatment until death or full time ventilation, and adverse events attributable to treatment during the trial period. DATA COLLECTION AND ANALYSIS Two authors independently reviewed and extracted data from all potentially relevant trials. Pooled relative risks and pooled weighted standardized mean differences were to be calculated to assess treatment efficacy MAIN RESULTS Four randomized placebo-controlled trials on treatment for SMA type II and III were found and included in the review. The treatments were creatine, phenylbutyrate, gabapentin and thyrotropin releasing hormone. None of these trials showed any effect on the outcome measures in patients with SMA type II and III. None of the patients in any of the four trials died or reached the state of full time ventilation and serious side effects were infrequent. AUTHORS' CONCLUSIONS There is no proven efficacious drug treatment for SMA type II and III.
Collapse
Affiliation(s)
- Wendy M J Bosboom
- Department of Neurology, Sint Lucas Andreas Hospital, Jan Tooropstraat 164, Amsterdam, Netherlands, 1061 AE.
| | | | | | | | | |
Collapse
|
46
|
Bosboom WMJ, Vrancken AFJE, van den Berg LH, Wokke JHJ, Iannaccone ST. Drug treatment for spinal muscular atrophy type I. Cochrane Database Syst Rev 2009:CD006281. [PMID: 19160274 DOI: 10.1002/14651858.cd006281.pub2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is caused by degeneration of anterior horn cells, which leads to progressive muscle weakness. Children with SMA type I will never be able to sit without support and usually die by the age of two years. There are no known efficacious drug treatments that influence the disease course. OBJECTIVES To evaluate if drug treatment is able to slow or arrest the disease progression of SMA type I, and to assess if such therapy can be given safely. Drug treatment for SMA type II and III will be will be the topic of a separate Cochrane review. SEARCH STRATEGY We searched the Cochrane Neuromuscular Disease Group Trials Register (September 30 2008, The Cochrane Library (Issue 3, 2008), MEDLINE (January 1966 to June 2008), EMBASE (January 1980 to June 2008), ISI (January 1988 to June 2008), and ACP Journal Club (January 1991 to June 2008). SELECTION CRITERIA All randomized or quasi-randomized trials that examined the efficacy of drug treatment for SMA type 1 were sought. Participants had to fulfil clinical criteria and, in studies including genetic analysis to confirm the diagnosis, have a deletion or mutation of the SMN1 gene (5q11.2-13.2)The primary outcome measure was to be time from birth until death or full time ventilation. Secondary outcome measures were to be development of rolling, sitting or standing within one year after the onset of treatment, and adverse events attributable to treatment during the trial period. DATA COLLECTION AND ANALYSIS Two authors (WB and AV) independently reviewed and extracted data from all potentially relevant trials. For included studies pooled relative risks and pooled weighted standardized mean differences were to be calculated to assess treatment efficacy MAIN RESULTS One small randomized-controlled study comparing riluzole treatment to placebo for SMA type 1 was identified and included in the review. Regarding the primary outcome measure three of seven children treated with riluzole were still alive at the age of 30, 48 and 64 months, whereas all three children in the placebo group died, but the difference was not statistically significant. Regarding the secondary outcome measures none of the patients in the riluzole or placebo group developed the ability to roll, sit or stand, and no adverse effects were observed. AUTHORS' CONCLUSIONS No drug treatment for SMA type I has been proven to have significant efficacy.
Collapse
Affiliation(s)
- Wendy M J Bosboom
- Department of Neurology, Sint Lucas Andreas Hospital, Jan Tooropstraat 164, Amsterdam, Netherlands, 1061 AE.
| | | | | | | | | |
Collapse
|
47
|
Affiliation(s)
- Victor Dubowitz
- The Dubowitz Neuromuscular Centre, UCL Institute of Child Health, 30 Guilford St., London WC1N 1EH, UK
| |
Collapse
|
48
|
Abstract
Spinal muscular atrophy (SMA) is a potentially devastating and lethal neuromuscular disease frequently manifesting in infancy and childhood. The discovery of the underlying mutation in the survival of motor neurons 1 (SMN1) gene has accelerated preclinical research, leading to treatment targets and transgenic mouse models, but there is still no effective treatment. The clinical severity is inversely related to the copy number of SMN2, a modifying gene producing some full-length SMN transcript. Drugs shown to increase SMN2 function in vitro, therefore, have the potential to benefit patients with SMA. Because several drugs are now on the horizon of clinical investigation, we review recent clinical trials for SMA and discuss the challenges and opportunities associated with SMA drug development. Although an orphan disease, SMA is well-positioned for successful trials given that it has a common genetic etiology in most cases, that it can be readily diagnosed, that preclinical research in vitro and in transgenic animals has identified candidate compounds, and that trial networks have been established.
Collapse
Affiliation(s)
- Maryam Oskoui
- />Montreal Neurological Institute, McGill University, H3A 2B4 Montreal, Quebec Canada
| | - Petra Kaufmann
- />The Neurological Institute, Columbia University, 710 West 168th Street, 10032-3784 New York, NY
| |
Collapse
|
49
|
Han JJ, McDonald CM. Diagnosis and clinical management of spinal muscular atrophy. Phys Med Rehabil Clin N Am 2008; 19:661-80, xii. [PMID: 18625423 DOI: 10.1016/j.pmr.2008.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by degeneration of lower motor neurons, with resulting progressive muscle weakness. The clinical phenotype and disease severity can be varied and occupy a wide spectrum. Although many advances have been made regarding our understanding of SMA, no cure is yet available. The care of patients who have SMA can often be complex, with many medical issues to consider. When possible, a multidisciplinary team approach is effective. The current understanding of SMA, and the clinical management and rehabilitative care of patients who have SMA, are discussed in this article.
Collapse
Affiliation(s)
- Jay J Han
- Department of Physical Medicine and Rehabilitation, University of California-Davis, 4860 Y Street, Suite 3850, Sacramento, CA 95817, USA.
| | | |
Collapse
|
50
|
Gennarelli M, Melchionda S, Fattorini C, Novelli G, Dallapiccola B. Genotyping of spinal muscular atrophy families with linked DNA probes. Clin Genet 2008; 42:317-9. [PMID: 1362926 DOI: 10.1111/j.1399-0004.1992.tb03264.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report on linkage analysis and haplotype characterization in 40 Italian families with spinal muscular atrophy (SMA). The investigated loci included D5S6, D5S112, D5S39, and D5S76. No evidence of unlinked families was found. Thirty-two (80%) of the examined families were fully informative for prenatal diagnosis and carrier detection. The frequencies of individual alleles did not differ between SMA and normal chromosomes.
Collapse
Affiliation(s)
- M Gennarelli
- Dipartimento di Sanità Pubblica e Biologia Cellulare, Università Tor Vergata, Roma, Italy
| | | | | | | | | |
Collapse
|