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Mitra S, Gumusgoz E, Minassian BA. Lafora disease: Current biology and therapeutic approaches. Rev Neurol (Paris) 2021; 178:315-325. [PMID: 34301405 DOI: 10.1016/j.neurol.2021.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/21/2021] [Accepted: 06/16/2021] [Indexed: 12/19/2022]
Abstract
The ubiquitin system impacts most cellular processes and is altered in numerous neurodegenerative diseases. However, little is known about its role in neurodegenerative diseases due to disturbances of glycogen metabolism such as Lafora disease (LD). In LD, insufficiently branched and long-chained glycogen forms and precipitates into insoluble polyglucosan bodies (Lafora bodies), which drive neuroinflammation, neurodegeneration and epilepsy. LD is caused by mutations in the gene encoding the glycogen phosphatase laforin or the gene coding for the laforin interacting partner ubiquitin E3 ligase malin. The role of the malin-laforin complex in regulating glycogen structure remains with full of gaps. In this review we bring together the disparate body of data on these two proteins and propose a mechanistic hypothesis of the disease in which malin-laforin's role to monitor and prevent over-elongation of glycogen branch chains, which drive glycogen molecules to precipitate and accumulate into Lafora bodies. We also review proposed connections between Lafora bodies and the ensuing neuroinflammation, neurodegeneration and intractable epilepsy. Finally, we review the exciting activities in developing therapies for Lafora disease based on replacing the missing genes, slowing the enzyme - glycogen synthase - that over-elongates glycogen branches, and introducing enzymes that can digest Lafora bodies. Much more work is needed to fill the gaps in glycogen metabolism in which laforin and malin operate. However, knowledge appears already adequate to advance disease course altering therapies for this catastrophic fatal disease.
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Affiliation(s)
- S Mitra
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - E Gumusgoz
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - B A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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Brewer MK, Uittenbogaard A, Austin GL, Segvich DM, DePaoli-Roach A, Roach PJ, McCarthy JJ, Simmons ZR, Brandon JA, Zhou Z, Zeller J, Young LEA, Sun RC, Pauly JR, Aziz NM, Hodges BL, McKnight TR, Armstrong DD, Gentry MS. Targeting Pathogenic Lafora Bodies in Lafora Disease Using an Antibody-Enzyme Fusion. Cell Metab 2019; 30:689-705.e6. [PMID: 31353261 PMCID: PMC6774808 DOI: 10.1016/j.cmet.2019.07.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 05/28/2019] [Accepted: 07/03/2019] [Indexed: 12/15/2022]
Abstract
Lafora disease (LD) is a fatal childhood epilepsy caused by recessive mutations in either the EPM2A or EPM2B gene. A hallmark of LD is the intracellular accumulation of insoluble polysaccharide deposits known as Lafora bodies (LBs) in the brain and other tissues. In LD mouse models, genetic reduction of glycogen synthesis eliminates LB formation and rescues the neurological phenotype. Therefore, LBs have become a therapeutic target for ameliorating LD. Herein, we demonstrate that human pancreatic α-amylase degrades LBs. We fused this amylase to a cell-penetrating antibody fragment, and this antibody-enzyme fusion (VAL-0417) degrades LBs in vitro and dramatically reduces LB loads in vivo in Epm2a-/- mice. Using metabolomics and multivariate analysis, we demonstrate that VAL-0417 treatment of Epm2a-/- mice reverses the metabolic phenotype to a wild-type profile. VAL-0417 is a promising drug for the treatment of LD and a putative precision therapy platform for intractable epilepsy.
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Affiliation(s)
- M Kathryn Brewer
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Annette Uittenbogaard
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Grant L Austin
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Dyann M Segvich
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Anna DePaoli-Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Peter J Roach
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - John J McCarthy
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Zoe R Simmons
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jason A Brandon
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Zhengqiu Zhou
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Jill Zeller
- Northern Biomedical Research, Spring Lake, MI 49456, USA
| | - Lyndsay E A Young
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - Ramon C Sun
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | - James R Pauly
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
| | | | | | | | | | - Matthew S Gentry
- Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, KY 40536, USA; Lafora Epilepsy Cure Initiative, University of Kentucky College of Medicine, Lexington, KY 40536, USA; University of Kentucky Epilepsy & Brain Metabolism Alliance, University of Kentucky College of Medicine, Lexington, KY 40536, USA.
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Inayat F, Ullah W, Lodhi HT, Khan ZH, Ilyas G, Ali NS, Abdullah HMA. Lafora Disease Masquerading as Hepatic Dysfunction. Cureus 2018; 10:e3197. [PMID: 30498646 PMCID: PMC6257626 DOI: 10.7759/cureus.3197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Lafora disease is fatal intractable progressive myoclonic epilepsy. It is frequently characterized by epileptic seizures, difficulty walking, muscle spasms, and dementia in late childhood or adolescence. We chronicle here an unusual case of an asymptomatic young male soccer player who presented with elevated liver enzymes. Neurological examination was unremarkable. The diagnostic workup for hepatitis, infectious etiologies, autoimmune disorders, hemochromatosis, Wilson's disease, alpha-1 antitrypsin deficiency, and other related diseases was inconclusive. He subsequently underwent an uneventful percutaneous liver biopsy. Based on the pathognomonic histopathological findings, Lafora disease was considered the likely etiology. The present study is a unique illustration of this rare disorder initially manifesting with abnormal liver enzymes. It underscores the importance of clinical suspicion of Lafora disease in cases with unexplained hepatic dysfunction. Prompt liver biopsy and genetic testing should be performed to antedate the onset of symptoms in these patients.
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Affiliation(s)
- Faisal Inayat
- Internal Medicine, Allama Iqbal Medical College, Lahore, PAK
| | - Waqas Ullah
- Internal Medicine, Abington Jefferson Health, Miami Beach, USA
| | - Hanan T Lodhi
- Infectious Diseases, University of Nebraska Medical Center, Omaha, USA
| | - Zarak H Khan
- Internal Medicine, St. Mary Mercy Hospital, Livonia, USA
| | - Ghulam Ilyas
- Pathology, The State University of New York Downstate Medical Center, New York, USA
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Lafora disease with novel autopsy findings: a case report with endocrine involvement and literature review. Pediatr Neurol 2014; 51:713-6. [PMID: 25217339 DOI: 10.1016/j.pediatrneurol.2014.07.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/28/2014] [Accepted: 07/31/2014] [Indexed: 11/20/2022]
Abstract
BACKGROUND Lafora disease is a rare, autosomal recessive, progressive myoclonic epilepsy with onset typically in the second decade of life and uniformly fatal outcome. Most of the current literature focuses on diagnosis, genetic basis, neurological signs, and possible treatment of this currently incurable disease. On literature review of over 50 articles including over 300 patients, there were no comments on or pathologic description of endocrinologic issues in relation to Lafora disease. PATIENT DESCRIPTION We describe a patient with Lafora disease with severe neurological deterioration. During hospitalization for urosepsis, he exhibited thyrotoxicosis with a free thyroxine (T4) level greater than 7.77 ng/dL. On autopsy, he had lymphocytic thyroiditis and Lafora bodies throughout his organs including the anterior pituitary, hypothalamus, and pancreas. CONCLUSIONS This is the first report of the pathologic findings of Lafora bodies in endocrine organs. Although this patient's thyrotoxic state was likely not a direct result of his Lafora disease, given the diffuse deposition of Lafora bodies, endocrinologic abnormalities should be considered in patients with Lafora disease. Furthermore, acute decompensation in these individuals may arise not from a declining neurological status but from a coincidental disease process.
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Abstract
Atrioventricular (AV) block is a delay or an interruption in the transmission of an impulse from atria to ventricles due to an anatomic or a functional impairment in the conduction system. Atrioventricular block may be congenital or acquired. Electrocardiographic screening of asymptomatic school-aged children (median, 12.4 years) in Japan found the prevalence of a third-degree AV block to be 2 per 100,000. We report a case of asymptomatic complete AV block of unknown etiology in a 13-year-old child who did not require pacemaker placement. The importance of recognizing an asymptomatic complete AV block in the pediatric population, the classification and controversies of pacemaker placement, and the complications of pacemaker placement are discussed.
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Vernia S, Heredia M, Criado O, Rodriguez de Cordoba S, Garcia-Roves PM, Cansell C, Denis R, Luquet S, Foufelle F, Ferre P, Sanz P. Laforin, a dual specificity phosphatase involved in Lafora disease, regulates insulin response and whole-body energy balance in mice. Hum Mol Genet 2011; 20:2571-84. [DOI: 10.1093/hmg/ddr157] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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Abstract
Lafora disease is a rare, fatal, autosomal recessive, progressive myoclonic epilepsy. It may also be considered as a disorder of carbohydrate metabolism because of the formation of polyglucosan inclusion bodies in neural and other tissues due to abnormalities of the proteins laforin or malin. The condition is characterized by epilepsy, myoclonus and dementia. Diagnostic findings on MRI and neurophysiological testing are not definitive and biopsy or genetic studies may be required. Therapy in Lafora disease is currently limited to symptomatic management of the epilepsy, myoclonus and intercurrent complications. With a greater understanding of the pathophysiological processes involved, there is justified hope for future therapies.
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Affiliation(s)
- Thomas S Monaghan
- Department of Neurology and Neuroscience, Beaumont Hospital and Royal College of Surgeons in Ireland, Dublin 9, Ireland
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Wick R, Byard RW. Mechanisms of unexpected and/or sudden death in Lafora disease. Forensic Sci Int 2006; 163:144-7. [PMID: 16326059 DOI: 10.1016/j.forsciint.2005.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2005] [Revised: 11/02/2005] [Accepted: 11/02/2005] [Indexed: 11/17/2022]
Abstract
A 23-year-old male was found dead wedged between two chairs at his home address. His past history included a diagnosis of Lafora disease (a type of heritable progressive myoclonic epilepsy) at the age of 16 years. This had been characterised by the development of epilepsy and progressive motor impairment and mental deterioration. Diagnosis had been confirmed by demonstration of mutation in the EPM2A gene on chromosome 6q24. At autopsy, petechial haemorrhages were noted of the face and conjunctivae bilaterally. There were no other significant findings apart from gastric contents within the airways. Death was attributed to positional asphyxia complicated by aspiration of gastric contents. Although death in Lafora disease is usually predictable and often protracted, sudden and/or unexpected death may occur and involve status epilepticus, sudden unexpected epileptic death, choking, aspiration of gastric contents, and cardiac arrhythmias. In addition, the possibility exists of unnatural causes of death, such as accidents, provoked by epilepsy or physical inability of the victims to extricate themselves from dangerous situations, or homicides, provoked by difficulties in caring for individuals with significant and progressive disabilities.
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Affiliation(s)
- Regula Wick
- Forensic Pathology, Forensic Science SA and Department of Histopathology, Women's and Children's Hospital, Adelaide, Australia
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Abstract
Lafora's disease is one of five inherited progressive myoclonus epilepsy syndromes. It is an autosomal-recessive disorder with onset in late childhood or adolescence. Characteristic seizures include myoclonic and occipital lobe seizures with visual hallucinations, scotomata, and photoconvulsions. The course of the disease consists of worsening seizures and an inexorable decline in mental and other neurologic functions that result in dementia and death within 10 years of onset. Pathology reveals pathognomonic polyglucosan inclusions that are not seen in any other progressive myoclonus epilepsy. Lafora's disease is one of several neurologic conditions associated with brain polyglucosan bodies. Why Lafora's polyglucosan bodies alone are associated with epilepsy is unknown and is discussed in this article. Up to 80% of patients with Lafora's disease have mutations in the EPM2A gene. Although common mutations are rare, simple genetic tests to identify most mutations have been established. At least one other still-unknown gene causes Lafora's disease. The EPM2A gene codes for the protein laforin, which localizes at the plasma membrane and the rough endoplasmic reticulum and functions as a dual-specificity phosphatase. Work toward establishing the connection between laforin and Lafora's disease polyglucosans is underway, as are attempts to replace it into the central nervous system of patients with Lafora's disease.
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Affiliation(s)
- B A Minassian
- Division of Neurology, Department of Paediatrics, The Hospital for Sick Children and The University of Toronto, M5G 1X8, Toronto, Ontario, Canada
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