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Wang Y, Huang C, Liou G, Hsueh H, Liang C, Tseng H, Huang S, Chao C, Hsieh S, Tzeng S. A molecular basis for tetramer destabilization and aggregation of transthyretin Ala97Ser. Protein Sci 2023; 32:e4610. [PMID: 36851846 PMCID: PMC10037696 DOI: 10.1002/pro.4610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 02/02/2023] [Accepted: 02/23/2023] [Indexed: 03/01/2023]
Abstract
Transthyretin (TTR)-related amyloidosis (ATTR) is a syndrome of diseases characterized by the extracellular deposition of fibrillar materials containing TTR variants. Ala97Ser (A97S) is the major mutation reported in Taiwanese ATTR patients. Here, we combine atomic resolution structural information together with the biochemical data to demonstrate that substitution of polar Ser for a small hydrophobic side chain of Ala at residue 97 of TTR largely influences the local packing density of the FG-loop, thus leading to the conformational instability of native tetramer, the increased monomeric species, and thus the enhanced amyloidogenicity of apo-A97S. Based on calorimetric studies, the tetramer destabilization of A97S can be substantially altered by interacting with native stabilizers via similarly energetic patterns compared to that of wild-type (WT) TTR; however, stabilizer binding partially rearranges the networks of hydrogen bonding in TTR variants while FG-loops of tetrameric A97S still remain relatively flexible. Moreover, TTR in complexed with holo-retinol binding protein 4 is slightly influenced by the structural and dynamic changes of FG-loop caused by A97S substitution with an approximately five-fold difference in binding affinity. Collectively, our findings suggest that the amyloidogenic A97S mutation destabilizes TTR by increasing the flexibility of the FG-loop in the monomer, thus modulating the rate of amyloid fibrillization.
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Affiliation(s)
- Yi‐Shiang Wang
- Institute of Biochemistry and Molecular BiologyCollege of Medicine, National Taiwan UniversityTaipeiTaiwan
| | - Chun‐Hsiang Huang
- Protein diffraction group, Experimental instrumentation divisionNational Synchrotron Radiation Research CenterHsinchuTaiwan
| | - Gunn‐Guang Liou
- Office of Research and Development, College of MedicineNational Taiwan UniversityTaipeiTaiwan
| | - Hsueh‐Wen Hsueh
- Department of Anatomy and Cell Biology, College of MedicineNational Taiwan UniversityTaipeiTaiwan
| | - Chi‐Ting Liang
- Institute of Biochemistry and Molecular BiologyCollege of Medicine, National Taiwan UniversityTaipeiTaiwan
| | - Hsi‐Ching Tseng
- Instrumentation CenterNational Taiwan UniversityTaipeiTaiwan
| | | | - Chi‐Chao Chao
- Department of NeurologyNational Taiwan University HospitalTaipeiTaiwan
| | - Sung‐Tsang Hsieh
- Graduate Institute of Brain and Mind SciencesTaipeiTaiwan
- Graduate Institute of Clinical MedicineTaipeiTaiwan
- Center of Precision MedicineNational Taiwan University College of MedicineTaipeiTaiwan
| | - Shiou‐Ru Tzeng
- Institute of Biochemistry and Molecular BiologyCollege of Medicine, National Taiwan UniversityTaipeiTaiwan
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Vilas-Boas MDC, Fonseca PFP, Sousa IM, Cardoso MN, Cunha JPS, Coelho T. Gait Characterization and Analysis of Hereditary Amyloidosis Associated with Transthyretin Patients: A Case Series. J Clin Med 2022; 11:jcm11143967. [PMID: 35887731 PMCID: PMC9320786 DOI: 10.3390/jcm11143967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/30/2022] [Accepted: 07/02/2022] [Indexed: 02/04/2023] Open
Abstract
Hereditary amyloidosis associated with transthyretin (ATTRv), is a rare autosomal dominant disease characterized by length-dependent symmetric polyneuropathy that has gait impairment as one of its consequences. The gait pattern of V30M ATTRv amyloidosis patients has been described as similar to that of diabetic neuropathy, associated with steppage, but has never been quantitatively characterized. In this study we aim to characterize the gait pattern of patients with V30M ATTRv amyloidosis, thus providing information for a better understanding and potential for supporting diagnosis and disease progression evaluation. We present a case series in which we conducted two gait analyses, 18 months apart, of five V30M ATTRv amyloidosis patients using a 12-camera, marker based, optical system as well as six force platforms. Linear kinematics, ground reaction forces, and angular kinematics results are analyzed for all patients. All patients, except one, showed a delayed toe-off in the second assessment, as well as excessive pelvic rotation, hip extension and external transverse rotation and knee flexion (in stance and swing phases), along with reduced vertical and mediolateral ground reaction forces. The described gait anomalies are not clinically quantified; thus, gait analysis may contribute to the assessment of possible disease progression along with the clinical evaluation.
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Affiliation(s)
- Maria do Carmo Vilas-Boas
- Centro Hospitalar Universitário do Porto, Hospital Santo António, Unidade Corino de Andrade, E.P.E., Largo do Prof. Abel Salazar, 4099-001 Porto, Portugal; (M.N.C.); (T.C.)
- INESC TEC (Instituto de Engenharia de Sistemas e Computadores, Tecnologia e Ciência), FEUP (Faculdade de Engenharia da Universidade do Porto), University of Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal;
- Correspondence: ; Tel.: +351-22-209-4000
| | - Pedro Filipe Pereira Fonseca
- LABIOMEP: Porto Biomechanics Laboratory, University of Porto, R. Dr. Plácido de Costa, 91, 4200-450 Porto, Portugal; (P.F.P.F.); (I.M.S.)
| | - Inês Martins Sousa
- LABIOMEP: Porto Biomechanics Laboratory, University of Porto, R. Dr. Plácido de Costa, 91, 4200-450 Porto, Portugal; (P.F.P.F.); (I.M.S.)
- Escola Superior de Biotecnologia, Universidade Católica Portuguesa Rua de Diogo Botelho, 1327, 4169-005 Porto, Portugal
| | - Márcio Neves Cardoso
- Centro Hospitalar Universitário do Porto, Hospital Santo António, Unidade Corino de Andrade, E.P.E., Largo do Prof. Abel Salazar, 4099-001 Porto, Portugal; (M.N.C.); (T.C.)
| | - João Paulo Silva Cunha
- INESC TEC (Instituto de Engenharia de Sistemas e Computadores, Tecnologia e Ciência), FEUP (Faculdade de Engenharia da Universidade do Porto), University of Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal;
- LABIOMEP: Porto Biomechanics Laboratory, University of Porto, R. Dr. Plácido de Costa, 91, 4200-450 Porto, Portugal; (P.F.P.F.); (I.M.S.)
| | - Teresa Coelho
- Centro Hospitalar Universitário do Porto, Hospital Santo António, Unidade Corino de Andrade, E.P.E., Largo do Prof. Abel Salazar, 4099-001 Porto, Portugal; (M.N.C.); (T.C.)
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Qin Q, Wei C, Piao Y, Lian F, Wu H, Zhou A, Wang F, Zuo X, Han Y, Lyu J, Guo D, Jia J. Current Review of Leptomeningeal Amyloidosis Associated With Transthyretin Mutations. Neurologist 2021; 26:189-195. [PMID: 34491937 PMCID: PMC8423141 DOI: 10.1097/nrl.0000000000000337] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Leptomeningeal amyloidosis (LA) represents a rare subtype of familial transthyretin (TTR) amyloidosis, characterized by deposition of amyloid in cranial and spinal leptomeninges. Of >120 TTR mutations identified, few have been associated with LA. CASE REPORT A 27-year-old male presented with a 2-year history of progressive symptoms including cognitive decline and right-sided weakness and numbness. Cerebrospinal fluid (CSF) analyses demonstrated high protein level. Gadolinium-enhanced magnetic resonance imaging (MRI) revealed extensive leptomeningeal enhancement over the surface of the brain and spinal cord. Pathologic analyses revealed a TTR mutation c.113A>G (p.D38G). REVIEW SUMMARY Fifteen mutations and genotype-phenotype correlation of 72 LA patients have been summarized to provide an overview of LA associated with transthyretin mutations. The mean age of clinical onset was 44.9 years and the neurological symptoms primarily included cognitive impairment, headache, ataxia seizures and hearing, visual loss. CSF analysis showed elevated high CSF protein level and MRI revealed extensive leptomeningeal enhancement. CONCLUSION Clinicians should be aware of this rare form of familial transthyretin amyloidosis as well as its typical MRI enhancement and high CSF protein. The important role of biopsy, genetic testing and the potential early diagnosis value of contrast MRI were suggested. Early recognition of these characteristics is important to provide misdiagnosis and shorten the time before correct diagnosis. These findings expand the phenotypic spectrum of TTR gene and have implications for the diagnosis, treatment, and systematic study of LA.
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Affiliation(s)
- Qi Qin
- Department of Neurology, Innovation Center for Neurological Disorders
- Center for Cognitive Disorders, Beijing Geriatric Hospital
| | - Cuibai Wei
- Department of Neurology, Innovation Center for Neurological Disorders
| | | | | | - Hao Wu
- Department of Neurosurgery, Xuanwu Hospital of Capital Medical University
| | - Aihong Zhou
- Department of Neurology, Innovation Center for Neurological Disorders
| | - Fen Wang
- Department of Neurology, Innovation Center for Neurological Disorders
| | - Xiumei Zuo
- Department of Neurology, Innovation Center for Neurological Disorders
| | - Yue Han
- Department of Neurology, Innovation Center for Neurological Disorders
| | - Jihui Lyu
- Department of Neurosurgery, Xuanwu Hospital of Capital Medical University
| | - Dongmei Guo
- Department of Neurology, Innovation Center for Neurological Disorders
| | - Jianping Jia
- Department of Neurology, Innovation Center for Neurological Disorders
- Center of Alzheimer’s Disease, Beijing Institute for Brain Disorders
- Beijing Key Laboratory of Geriatric Cognitive Disorders
- Neurodegenerative Laboratory of Ministry of Education of the People’s Republic of China, Beijing, China
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Du K, Li F, Wang H, Miao Y, Lv H, Zhang W, Wang Z, Yuan Y, Meng L. Hereditary transthyretin amyloidosis in mainland China: a unicentric retrospective study. Ann Clin Transl Neurol 2021; 8:831-841. [PMID: 33739616 PMCID: PMC8045954 DOI: 10.1002/acn3.51328] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/31/2021] [Accepted: 02/06/2021] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE This study aims to report the genotypes and phenotypes of hereditary transthyretin amyloidosis (ATTR) in a large Chinese cohort, yet the clinical and genetic profiles of ATTR remain elusive in mainland China. METHODS Fifty-four patients with molecularly confirmed ATTR from 39 unrelated families were identified by sequencing the TTR gene. Sural nerve biopsies were performed in 40 of these cases. The clinical and electrophysiological data were retrospectively collected and analyzed. RESULTS The male/female ratio was 42:12. The average age of patients at the onset of the disease was 47.8 ± 13.0 years. The late-onset type occurred in 29 cases (53.7%). Twenty-two probands (56.4%) had a family history with ATTR. The initial symptoms were limb paresthesia in 33 cases (61.1%), autonomic dysfunction in 15 cases (27.8%), and blurred vision in 6 cases (11.1%). A total of 22 different TTR mutations were identified, including Val30Met (25.6%) in 10 families in North China and Ala97Ser in 4 families (10.3%) in South China. Electrophysiological studies revealed general sensorimotor axonal polyneuropathy in 33/44 cases (75.0%), mixed neuropathy with axonal and demyelinating impairment features in 9/44 cases (20.5%) and isolated carpal tunnel syndrome in two cases. Sural nerve biopsies revealed positive Congo red staining in 16/40 cases (40.0%). CONCLUSION Chinese patients with ATTR exhibited heterogeneous TTR genotypes and clinical phenotypes. Val30Met remains the most common mutation type in mainland China.
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Affiliation(s)
- Kang Du
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Fan Li
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Hui Wang
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Yuanfeng Miao
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - He Lv
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Wei Zhang
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Zhaoxia Wang
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Yun Yuan
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
| | - Lingchao Meng
- Department of NeurologyPeking University First Hospital8 Xishiku StreetXicheng DistrictBeijing100034China
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Möckelind S, Axelsson J, Pilebro B, Lindqvist P, Suhr OB, Sundström T. Quantification of cardiac amyloid with [ 18F]Flutemetamol in patients with V30M hereditary transthyretin amyloidosis. Amyloid 2020; 27:191-199. [PMID: 32400202 DOI: 10.1080/13506129.2020.1760237] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background: Hereditary transthyretin amyloid (ATTRv) is a systemic amyloidosis with mainly neurological and cardiac symptoms. The aim of this study was to evaluate the outcome of [18F]Flutemetamol PET/CT-scan of the heart in long-term survivors with ATTRV30M amyloidosis.Methods: Twenty-one patients with ATTRV30M amyloidosis and predominantly neurological symptoms, mainly negative on cardiac 99mtechnetium-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD)-scintigraphy, were examined with a dynamic [18F]Flutemetamol PET/CT-scan. Five patients suffering from Alzheimer's disease and one healthy individual served as controls. Volumes of interests were drawn over the intraventricular septum, lateral wall of the left ventricle and free wall of the right ventricle. Clinical records were reviewed for data from previous completed DPD-scintigraphy of the heart and echocardiography.Results: Patients with ATTRv amyloidosis had a higher cardiac uptake than the control-group in all analysed regions of the heart and could be identified with high accuracy (sensitivity 88%, specificity 100%) in static image acquisition at 30 or 60 min. We found no correlation between cardiac [18F]Flutemetamol uptake and clinical variables.Conclusion: In this small study of selected patients, cardiac [18F]Flutemetamol PET/CT could differentiate between healthy individuals and patients with ATTRV30M. [18F]Flutemetamol PET/CT imaging of amyloidosis in patients with a negative DPD-scintigraphy has a potential as a diagnostic method.
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Affiliation(s)
- Sofia Möckelind
- Department of Radiation Science, Radiation Physics, Umeå University, Umeå, Sweden
| | - Jan Axelsson
- Department of Radiation Science, Radiation Physics, Umeå University, Umeå, Sweden
| | - Björn Pilebro
- Department of Public Health and Clinical medicine, Umeå University, Umeå, Sweden
| | - Per Lindqvist
- Department of Surgical and Perioperative Science, Umeå University, Umeå, Sweden
| | - Ole B Suhr
- Department of Public Health and Clinical medicine, Umeå University, Umeå, Sweden
| | - Torbjörn Sundström
- Department of Radiation Science, Diagnostic Radiology, Umeå University, Umeå, Sweden
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Rational Design, Synthesis, Characterization and Evaluation of Iodinated 4,4'-Bipyridines as New Transthyretin Fibrillogenesis Inhibitors. Molecules 2020; 25:molecules25092213. [PMID: 32397334 PMCID: PMC7248964 DOI: 10.3390/molecules25092213] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 04/29/2020] [Accepted: 05/06/2020] [Indexed: 02/06/2023] Open
Abstract
The 3,3',5,5'-tetrachloro-2-iodo-4,4'-bipyridine structure is proposed as a novel chemical scaffold for the design of new transthyretin (TTR) fibrillogenesis inhibitors. In the frame of a proof-of-principle exploration, four chiral 3,3',5,5'-tetrachloro-2-iodo-2'-substituted-4,4'- bipyridines were rationally designed and prepared from a simple trihalopyridine in three steps, including a Cu-catalysed Finkelstein reaction to introduce iodine atoms on the heteroaromatic scaffold, and a Pd-catalysed coupling reaction to install the 2'-substituent. The corresponding racemates, along with other five chiral 4,4'-bipyridines containing halogens as substituents, were enantioseparated by high-performance liquid chromatography in order to obtain pure enantiomer pairs. All stereoisomers were tested against the amyloid fibril formation (FF) of wild type (WT)-TTR and two mutant variants, V30M and Y78F, in acid mediated aggregation experiments. Among the 4,4'-bipyridine derivatives, interesting inhibition activity was obtained for both enantiomers of the 3,3',5,5'-tetrachloro-2'-(4-hydroxyphenyl)-2-iodo-4,4'-bipyridine. In silico docking studies were carried out in order to explore possible binding modes of the 4,4'-bipyridine derivatives into the TTR. The gained results point out the importance of the right combination of H-bond sites and the presence of iodine as halogen-bond donor. Both experimental and theoretical evidences pave the way for the utilization of the iodinated 4,4'-bipyridine core as template to design new promising inhibitors of TTR amyloidogenesis.
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Current update in domino liver transplantation. Int J Surg 2020; 82S:163-168. [PMID: 32244002 DOI: 10.1016/j.ijsu.2020.03.017] [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] [Received: 12/29/2019] [Revised: 03/09/2020] [Accepted: 03/12/2020] [Indexed: 12/14/2022]
Abstract
Orthotopic liver transplantation is an established treatment for end stage liver diseases as well as for some severe metabolic disorders. With increasing number of patients on the waiting list and the ongoing shortage of livers available, domino liver transplantation (DLT) became an option to further expand the organ donor pool. DLT utilizes the explanted liver of one liver transplant recipient as a donor graft in another patient. Despite being a surgically, and logistically demanding procedure, excellent results could be achieved in experienced high-volume transplant centers. In this review we present the current world status of DLT.
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Derouault P, Chauzeix J, Rizzo D, Miressi F, Magdelaine C, Bourthoumieu S, Durand K, Dzugan H, Feuillard J, Sturtz F, Mérillou S, Lia AS. CovCopCan: An efficient tool to detect Copy Number Variation from amplicon sequencing data in inherited diseases and cancer. PLoS Comput Biol 2020; 16:e1007503. [PMID: 32049956 PMCID: PMC7041855 DOI: 10.1371/journal.pcbi.1007503] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 02/25/2020] [Accepted: 10/23/2019] [Indexed: 02/07/2023] Open
Abstract
Molecular diagnosis is an essential step of patient care. An increasing number of Copy Number Variations (CNVs) have been identified that are involved in inherited and somatic diseases. However, there are few existing tools to identify them among amplicon sequencing data generated by Next Generation Sequencing (NGS). We present here a new tool, CovCopCan, that allows the rapid and easy detection of CNVs in inherited diseases, as well as somatic data of patients with cancer, even with a low ratio of cancer cells to healthy cells. This tool could be very useful for molecular geneticists to rapidly identify CNVs in an interactive and user-friendly way.
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Affiliation(s)
| | - Jasmine Chauzeix
- CHU Limoges, Service Hématologie Biologique, Limoges, France
- Univ. Limoges, UMR CNRS 7276 CRIBL, Limoges, France
| | - David Rizzo
- CHU Limoges, Service Hématologie Biologique, Limoges, France
- Univ. Limoges, UMR CNRS 7276 CRIBL, Limoges, France
| | | | - Corinne Magdelaine
- Univ. Limoges, MMNP, EA 6309, Limoges, France
- CHU Limoges, Service Biochimie et Génétique Moléculaire, Limoges France
| | - Sylvie Bourthoumieu
- Univ. Limoges, MMNP, EA 6309, Limoges, France
- CHU Limoges, Service de Cytogénétique, Limoges, France
| | - Karine Durand
- CHU Limoges, Service Anatomie Pathologie, Limoges, France
- Univ. Limoges, EA CAPTur, Limoges, France
| | - Hélène Dzugan
- Univ. Limoges, MMNP, EA 6309, Limoges, France
- CHU Limoges, Service Biochimie et Génétique Moléculaire, Limoges France
| | - Jean Feuillard
- CHU Limoges, Service Hématologie Biologique, Limoges, France
- Univ. Limoges, UMR CNRS 7276 CRIBL, Limoges, France
| | - Franck Sturtz
- Univ. Limoges, MMNP, EA 6309, Limoges, France
- CHU Limoges, Service Biochimie et Génétique Moléculaire, Limoges France
| | | | - Anne-Sophie Lia
- CHU Limoges, UF de Bioinformatique, Limoges France
- Univ. Limoges, MMNP, EA 6309, Limoges, France
- CHU Limoges, Service Biochimie et Génétique Moléculaire, Limoges France
- * E-mail:
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Liu YT, Yen YJ, Ricardo F, Chang Y, Wu PH, Huang SJ, Lin KP, Yu TY. Biophysical characterization and modulation of Transthyretin Ala97Ser. Ann Clin Transl Neurol 2019; 6:1961-1970. [PMID: 31502419 PMCID: PMC6801203 DOI: 10.1002/acn3.50887] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 08/10/2019] [Accepted: 08/14/2019] [Indexed: 12/19/2022] Open
Abstract
Objective Ala97Ser (A97S) is the major transthyretin (TTR) mutation in Taiwanese patients of familial amyloid polyneuropathy (FAP), characterized by a late‐onset but rapidly deteriorated neuropathy. Tafamidis can restore the stability of some mutant TTR tetramers and slow down the progression of TTR‐FAP. However, there is little understanding of the biophysical features of A97S‐TTR mutant and the pharmacological modulation effect of tafamidis on it. This study aims to delineate the biophysical characteristics of A97S‐TTR and the pharmacological modulation effect of tafamidis on this mutant. Method The stability of TTR tetramers was assessed by urea denaturation and differential scanning calorimetry. Isothermal titration calorimetry (ITC) was used to measure the binding constant of tafamidis to TTR. Nuclear magnetic resonance spectroscopy (NMR) titration experiment was used to map out the tafamidis binding site. Results Chemical and thermal denaturation confirmed the destabilization effect of A97S. Consistent with other the amyloidogenic mutant, A97S‐TTR has slightly lower conformational stability. NMR revealed the binding site of A97S‐TTR with tafamidis is at the thyroxine binding pocket. The ITC experiments documented the high affinity of the binding which can effectively stabilize the A97S‐TTR tetramer. Interpretation This study confirmed the structural modulation effect of tafamidis on A97S‐TTR and implied the potential therapeutic benefit of tafamidis for A97S TTR‐FAP. This approach can be applied to investigate the modulation effect of tafamidis on other rare TTR variants and help to make individualized choices of available treatments for FAP patients.
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Affiliation(s)
- Yo-Tsen Liu
- Division of Epilepsy, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan.,National Yang-Ming University School of Medicine, Taipei, Taiwan.,Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan.,Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Yueh-Jung Yen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Frans Ricardo
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Yu Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Pei-Hao Wu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
| | - Shing-Jong Huang
- Instrumentation Center, National Taiwan University, Taipei, Taiwan
| | - Kon-Ping Lin
- National Yang-Ming University School of Medicine, Taipei, Taiwan.,Division of Peripheral Nervous System Disorders, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Tsyr-Yan Yu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan.,International Graduate Program of Molecular Science and Technology, National Taiwan University, Taipei, Taiwan
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