1
|
Carvalho E, Dias A, Coelho T, Sousa A, Alves-Ferreira M, Santos M, Lemos C. Hereditary transthyretin amyloidosis: a myriad of factors that influence phenotypic variability. J Neurol 2024; 271:5746-5761. [PMID: 38907862 DOI: 10.1007/s00415-024-12509-8] [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: 04/30/2024] [Revised: 06/02/2024] [Accepted: 06/07/2024] [Indexed: 06/24/2024]
Abstract
Hereditary transthyretin-related amyloidosis (ATTRv amyloidosis) is a rare and progressively debilitating disease characterized by the deposition of transthyretin (TTR) amyloid fibrils in various organs and tissues, most commonly in the heart and peripheral nerves. This pathological deposition can lead to significant organ dysfunction and, ultimately, organ failure. ATTRv amyloidosis exhibits a broad range of clinical presentations, from purely neurological symptoms to purely cardiac manifestations, as well as mixed phenotypes which result from both neurological and cardiac implications. This wide phenotypical spectrum realistically challenges disease diagnosis and prognosis, especially in individuals without or with an unknown family history. Multiple factors are thought to contribute to this variability, including genetic, epigenetic, and even environmental influences. Understanding these factors is crucial, as they can significantly affect disease expression and progression. This review aims to summarize each of these contributing factors, to help elucidate the current knowledge on the phenotypical variability of ATTRv amyloidosis.
Collapse
Affiliation(s)
- Estefânia Carvalho
- Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Andreia Dias
- Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Teresa Coelho
- Unidade Corino de Andrade (UCA), Centro Hospitalar Universitário de Santo António (CHUdSA), Porto, Portugal
| | - Alda Sousa
- Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Miguel Alves-Ferreira
- Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Center for Preditive and Preventive Genetics (CGPP), Institute for Molecular and Cell Biology (IBMC), Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
| | - Mariana Santos
- Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Institute for Molecular and Cell Biology (IBMC), Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal
| | - Carolina Lemos
- Instituto de Investigação e Inovação Em Saúde (i3S), University of Porto, Porto, Portugal.
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal.
| |
Collapse
|
2
|
Li Z, Kanazashi H, Tokashiki Y, Fujikawa R, Okagaki A, Katoh S, Kojima K, Haruna K, Matsushita N, Ishikawa TO, Chen H, Yamamura K. TTR exon-humanized mouse optimal for verifying new therapies for FAP. Biochem Biophys Res Commun 2022; 599:69-74. [PMID: 35176627 DOI: 10.1016/j.bbrc.2022.02.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 02/09/2022] [Indexed: 11/21/2022]
Abstract
Familial amyloidotic polyneuropathy (FAP) is caused by a mutation in the transthyretin (TTR) gene. In addition, deposition of wild-type TTR can cause senile systemic amyloidosis (SSA). To date, we have produced several transgenic mouse models for FAP and SSA by introducing TTR genes with different promoters or mutations. However, mouse TTR can associate with human TTR to produce hybrid tetramers in transgenic mice. Thus, these transgenic mice cannot be used to test the efficacy of a new therapy. In this study, we attempted to construct an optimized mouse model to verify a new therapy. The TTR gene consists of 4 exons and 3 introns. We prepared two gRNAs, one for the exon 1 and the other for exon 4, and a single donor vector carrying the whole TTR gene in which mouse exons were replaced with human exons. Using these vectors, we produced a TTR exon-humanized mouse with human exons and mouse introns using genome editing technology. These TTR exon-humanized mice showed normal TTR expression patterns in terms of serum TTR level and spatial specificity. These TTR exon-humanized mice will be useful for devising new treatment methods for FAP, including gene therapy.
Collapse
Affiliation(s)
- Zhenghua Li
- Department of Histology and Embryology, Harbin Medical University, Harbin, 150081, China; Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, 860-0811, Japan; TransGenic, Inc., Fukuoka, 810-0001, Japan
| | | | | | - Rie Fujikawa
- Biosafety Research Center, Kobe, 650-0047, Japan
| | | | - Sho Katoh
- Biosafety Research Center, Kobe, 650-0047, Japan
| | - Kenta Kojima
- Biosafety Research Center, Kobe, 650-0047, Japan
| | - Kyoko Haruna
- Biosafety Research Center, Kobe, 650-0047, Japan
| | | | | | - Hong Chen
- Department of Pulmonary and Critical Care Medicine, Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China.
| | - Kenichi Yamamura
- Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, 860-0811, Japan; TransGenic, Inc., Fukuoka, 810-0001, Japan.
| |
Collapse
|
3
|
Li X, Lyu Y, Shen J, Mu Y, Qiang L, Liu L, Araki K, Imbimbo BP, Yamamura KI, Jin S, Li Z. Amyloid deposition in a mouse model humanized at the transthyretin and retinol-binding protein 4 loci. J Transl Med 2018; 98:512-524. [PMID: 29330472 DOI: 10.1038/s41374-017-0019-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 11/29/2017] [Accepted: 12/02/2017] [Indexed: 12/19/2022] Open
Abstract
Familial amyloidotic polyneuropathy is an autosomal dominant disorder caused by a point mutation in the transthyretin (TTR) gene. The process of TTR amyloidogenesis begins with rate-limiting dissociation of the TTR tetramer. Thus, the TTR stabilizers, such as Tafamidis and Diflunisal, are now in clinical trials. Mouse models will be useful to testing the efficacy of these drugs. Although several mouse models have been generated, they all express mouse Rbp4. Thus, human TTR associates with mouse RBP4, resulting in different kinetic and thermodynamic stability profiles of TTR tetramers. To overcome this problem, we previously produced humanized mouse strains at both the TTR and Rbp4 loci (Ttr hTTRVal30 , Ttr hTTRMet30 , and Rbp4 hRBP4 ). By mating these mice, we produced double-humanized mouse strains, Ttr hTTRVal30/hTTRVal30 :Rbp4 hRBP4/hRBP4 and Ttr hTTRVal30/Met30 :Rbp4 hRBP4/hRBP4 . We used conventional transgenic mouse strains on a wild-type (Ttr +/+ :Tg[6.0hTTRMet30]) or knockout Ttr background (Ttr-/-:Tg[6.0hTTRMet30]) as reference strains. The double-humanized mouse showed 1/25 of serum hTTR and 1/40 of serum hRBP4 levels. However, amyloid deposition was more pronounced in Ttr hTTRVal30/Met30 :Rbp4 hRBP4/hRBP4 than in conventional transgenic mouse strains. In addition, a similar amount of amyloid deposition was also observed in Ttr hTTRVal30/ hTTRVal30 :Rbp4 hRBP4/ hRBP4 mice that carried the wild-type human TTR gene. Furthermore, amyloid deposition was first observed in the sciatic nerve without any additional genetic change. In all strains, anti-TTR antibody-positive deposits were found in earlier age and at higher percentage than amyloid fibril deposition. In double-humanized mice, gel filtration analysis of serum revealed that most hTTR was free of hRBP4, suggesting importance of free TTR for amyloid deposition.
Collapse
Affiliation(s)
- Xiangshun Li
- Division of Respiratory Disease, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Yanyi Lyu
- Department of Histology and Embryology, Harbin Medical University, Harbin, China
| | - Jingling Shen
- Department of Histology and Embryology, Harbin Medical University, Harbin, China
| | - Yanshuang Mu
- Yamamura Project Laboratory, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Lixia Qiang
- Division of Respiratory Disease, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Li Liu
- Department of Histology and Embryology, Harbin Medical University, Harbin, China
| | - Kimi Araki
- Department of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | | | - Ken-Ichi Yamamura
- Yamamura Project Laboratory, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Shoude Jin
- Division of Respiratory Disease, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, China.
| | - Zhenghua Li
- Department of Histology and Embryology, Harbin Medical University, Harbin, China.
| |
Collapse
|
4
|
Shah KB, Mankad AK, Castano A, Akinboboye OO, Duncan PB, Fergus IV, Maurer MS. Transthyretin Cardiac Amyloidosis in Black Americans. Circ Heart Fail 2017; 9:e002558. [PMID: 27188913 DOI: 10.1161/circheartfailure.115.002558] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 02/10/2016] [Indexed: 12/20/2022]
Abstract
Transthyretin-related cardiac amyloidosis is a progressive infiltrative cardiomyopathy that mimics hypertensive and hypertrophic heart disease and often goes undiagnosed. In the United States, the hereditary form disproportionately afflicts black Americans, who when compared with whites with wild-type transthyretin amyloidosis, a phenotypically similar condition, present with more advanced disease despite having a noninvasive method for early identification (genetic testing). Although reasons for this are unclear, this begs to consider the inadequate access to care, societal factors, or a biological basis. In an effort to improve awareness and explore unique characteristics, we review the pathophysiology, epidemiology, and therapeutic strategies for transthyretin amyloidosis and highlight diagnostic pitfalls and clinical pearls for identifying patients with amyloid heart disease.
Collapse
Affiliation(s)
- Keyur B Shah
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.).
| | - Anit K Mankad
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.)
| | - Adam Castano
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.)
| | - Olakunle O Akinboboye
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.)
| | - Phillip B Duncan
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.)
| | - Icilma V Fergus
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.)
| | - Mathew S Maurer
- From the Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond (K.B.S., A.K.M., P.B.D.); Division of Cardiology, Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA (A.K.M.); Division of Cardiology, Columbia University Medical Center, New York, NY (A.C., M.S.M.); Queens Heart Institute, Rosedale, NY (O.O.A.); Cardiac Health Management Network, Chester, VA (P.B.D.); and Division of Cardiology, Mount Sinai Medical Center, New York, NY (I.V.F.)
| |
Collapse
|
5
|
Petrakis I, Mavroeidi V, Stylianou K, Efthymiou G, Perakis K, Vardaki E, Stratigis S, Giannakakis K, Kourouniotis K, Amoiridis G, Plaitakis A, Saraiva MJ, Yamamura KI, Daphnis E. Human TTRV30M localization within podocytes in a transgenic mouse model of transthyretin related amyloidosis: does the environment play a role? Transgenic Res 2012; 22:101-16. [DOI: 10.1007/s11248-012-9632-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 07/02/2012] [Indexed: 11/24/2022]
|
6
|
Abstract
There has been much progress in our understanding of transthyretin (TTR)-related amyloidosis including familial amyloidotic polyneuropathy (FAP), senile systemic amyloidosis and its related disorders from many clinical and experimental aspects. FAP is an inherited severe systemic amyloidosis caused by mutated TTR, and characterized by amyloid deposition mainly in the peripheral nervous system and the heart. Liver transplantation is the only available treatment for the disease. FAP is now recognized not to be a rare disease, and to have many variations based on genetical and biochemical variations of TTR. This chapter covers the recent advances in the clinical and pathological aspects of, and therapeutic approaches to FAP, and the trend as to the molecular pathogenesis of TTR.
Collapse
Affiliation(s)
- Takamura Nagasaka
- Department of Neurology, University of Yamanashi, 1110 Shimokato, 409-3898, Chuou-city, Yamanashi, Japan,
| |
Collapse
|
7
|
Buxbaum JN. Animal models of human amyloidoses: are transgenic mice worth the time and trouble? FEBS Lett 2009; 583:2663-73. [PMID: 19627988 DOI: 10.1016/j.febslet.2009.07.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 07/15/2009] [Accepted: 07/15/2009] [Indexed: 02/05/2023]
Abstract
The amyloidoses are the prototype gain of toxic function protein misfolding diseases. As such, several naturally occurring animal models and their inducible variants provided some of the first insights into these disorders of protein aggregation. With greater analytic knowledge and the increasing flexibility of transgenic and gene knockout technology, new models have been generated allowing the interrogation of phenomena that have not been approachable in more reductionist systems, i.e. behavioral readouts in the neurodegenerative diseases, interactions among organ systems in the transthyretin amyloidoses and taking pre-clinical therapeutic trials beyond cell culture. The current review describes the features of both transgenic and non-transgenic models and discusses issues that appear to be unresolved even when viewed in their organismal context.
Collapse
Affiliation(s)
- Joel N Buxbaum
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
| |
Collapse
|
8
|
Momose Y, Maruyama A, Iwasaki T, Miyamoto Y, Itoh K. 16S rRNA gene sequence-based analysis of clostridia related to conversion of germfree mice to the normal state. J Appl Microbiol 2009; 107:2088-97. [PMID: 19614852 DOI: 10.1111/j.1365-2672.2009.04431.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To determine phylogenetic groups of clostridia inhabiting the mouse intestine that are essential for normalization of germfree (GF) mice. METHODS AND RESULTS Using both the culture method and cloning, clostridia inhabiting the mouse intestine were isolated, and phylogenetic analysis based on 16S rRNA gene sequences was carried out. As a result, the isolates were found to have novel sequences, and no isolate was determined to be identical to previously known identified clostridia. Although the taxonomy of mouse intestinal clostridia was complex, many of them belonged to Clostridium clusters XIVa and IV in conventional (CV) and limited flora mice and ex-germfree mice administered chloroform-treated CV mouse faeces. The clostridia that belonged to cluster XIVa were most often present and showed the highest diversity. CONCLUSIONS Clostridia belonging clusters XIVa and IV are dominant in the mouse intestine as in other gut ecosystems. The novel groups in these clusters are essential for normalization of GF mice. SIGNIFICANCE AND IMPACT OF THE STUDY The results of this study can be applied in the strict control of mouse intestinal microbiota and will provide important information for normalization of GF mice and also for research on microbiology of the mouse intestine.
Collapse
Affiliation(s)
- Y Momose
- Laboratory of Veterinary Public Health, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | | | | | | | | |
Collapse
|
9
|
Biescas E, Jirón W, Climent S, Fernández A, Pérez M, Weiss D, Solomon A, Luján L. AA Amyloidosis Induced in Sheep Principally Affects the Gastrointestinal Tract. J Comp Pathol 2009; 140:238-46. [DOI: 10.1016/j.jcpa.2008.12.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Revised: 12/04/2008] [Accepted: 12/12/2008] [Indexed: 10/21/2022]
|
10
|
Inoue S, Ohta M, Li Z, Zhao G, Takaoka Y, Sakashita N, Miyakawa K, Takada K, Tei H, Suzuki M, Masuoka M, Sakaki Y, Takahashi K, Yamamura KI. Specific pathogen free conditions prevent transthyretin amyloidosis in mouse models. Transgenic Res 2008; 17:817-26. [DOI: 10.1007/s11248-008-9180-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Accepted: 03/06/2008] [Indexed: 10/22/2022]
|
11
|
Bittencourt PL, Couto CA, Clemente C, Farias AQ, Palácios SA, Mies S, Goldberg AC. Phenotypic expression of familial amyloid polyneuropathy in Brazil. Eur J Neurol 2005; 12:289-93. [PMID: 15804246 DOI: 10.1111/j.1468-1331.2004.00941.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Familial amyloid polyneuropathy (FAP) is an inherited amyloidosis mainly associated with transthyretin Val30Met variant. Clinical heterogeneity has been reported in different populations with FAP and Va130Met variant. In order to characterize FAP expression in Brazilians and to compare its features to those reported in other cohorts, 44 Brazilian patients (27 females, median age 36 [23-53] years) with FAP and the Val30Met variant were investigated. Approximately 40% of their family members, with the exception, of parents and siblings, had FAP. Most of the patients had symptoms of peripheral neuropathy at onset. Median age at onset was 32 [20-44] years. Earlier onset was observed in males (27 [20-43] years in males vs. 33 [20-44] years in females, P = 0.02) and in patients whose parents had FAP (31 [20-44] years vs. 40 [37-43] years in patients, respectively with and without affected parents, P = 0.03). Phenotypic expression of FAP in Brazil is similar to the one reported in Portugal, characterized by high disease penetrance, early onset, particularly in males and in subjects with affected parents, and major symptoms of peripheral neuropathy. These data highlight the influence of common genetic factors, shared by both groups of patients, in disease expression.
Collapse
|
12
|
Takaoka Y, Ohta M, Miyakawa K, Nakamura O, Suzuki M, Takahashi K, Yamamura KI, Sakaki Y. Cysteine 10 is a key residue in amyloidogenesis of human transthyretin Val30Met. THE AMERICAN JOURNAL OF PATHOLOGY 2004; 164:337-45. [PMID: 14695346 PMCID: PMC1602210 DOI: 10.1016/s0002-9440(10)63123-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Type I familial amyloidotic polyneuropathy (FAP), a systemic amyloidosis, is characterized by aggregation of variant transthyretin (TTR Val30Met) into stable, insoluble fibrils. This aggregation is caused by genetic and environmental factors. Genetic factors have been studied extensively. However, little is known about environmental or physiological factors involved in the disease process, and their identification may be important for development of effective treatment. X-ray crystallography of normal and amyloidogenic human TTR Val30Met in type I FAP showed that the -SH side chain of cysteine at position 10 (Cys10) forms a hydrogen bond with Gly57 in normal TTR but not in TTR Val30Met. This result suggests a crucial role for the free Cys10 residue and possible involvement of physiological factors affecting Cys residue reactivity in TTR amyloidogenesis. To analyze amyloidogenesis in vivo, our group generated murine FAP models by transgenic technology, with human TTR Val30Met. The three lines of transgenic mice expressed amyloidogenic mutant TTR (Cys10/Met30), wild-type TTR (Cys10/Val30), and artificial Cys-free mutant TTR (Ser10/Met30). Histochemical investigation showed deposition of amyloid derived from human TTR only in amyloidogenic mutant TTR (Cys10/Met30) mice. Thus, the -SH residue in Cys10 plays a crucial role in TTR Val30Met amyloidogenesis in vivo. These data suggest the possibility of innovative treatment via physiological factors modulating Cys10 residue reactivity.
Collapse
Affiliation(s)
- Yutaka Takaoka
- Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Tagoe CE, Jacobson DR, Gallo G, Buxbaum JN. Mice transgenic for human TTR have the same frequency of renal TTR deposition whether maintained in conventional or specific pathogen free environments. Amyloid 2003; 10:262-6. [PMID: 14986486 DOI: 10.3109/13506120309041744] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Mice transgenic for many copies of the human wild type transthyretin gene were bred and maintained in a specific pathogen free environment until twelve months of age. At that time, half the animals were moved to a conventional animal facility. The incidence of both transthyretin and AA amyloid was the same in both groups at two years of age, indicating that in this model, the frequency, extent or nature of TTR-amyloid deposition did not differ significantly between conventional and specific pathogen-free environments.
Collapse
Affiliation(s)
- Clement E Tagoe
- New York University, Departments of Medicine & Pathology, 550 First Avenue, New York, NY 10016, USA
| | | | | | | |
Collapse
|