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Meléndrez-Balcázar E, Aranda-Vela K, Cervantes-Hernández A, López-Cureño S. Hereditary Transthyretin Amyloidosis and the Impact of Classic and New Treatments on Kidney Function: A Review. Am J Kidney Dis 2024; 84:224-231. [PMID: 38484868 DOI: 10.1053/j.ajkd.2024.01.527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 12/23/2023] [Accepted: 01/22/2024] [Indexed: 04/26/2024]
Abstract
Hereditary transthyretin amyloidosis (ATTRv) is a rare, progressive, and life-threatening disease caused by misfolded transthyretin (TTR) proteins that aggregate as abnormal amyloid fibrils and accumulate throughout the body. The kidney is one of the main organs affected in amyloid light chain (AL) amyloidosis and ATTRv amyloidosis. The most common clinical presentation is proteinuria, which consists mainly of albumin; this is the first step in the natural history of ATTRv nephropathy. Not all TTR mutations are equal in terms of ATTRv kidney involvement. Kidney involvement in ATTRv itself is difficult to define, given the numerous associated confounding factors. There are several treatments available to treat ATTRv, including orthotopic liver transplant (OLT), which is the classic treatment for ATTRv. However, we should be careful regarding the use of calcineurin inhibitors in the setting of OLT because these can be nephrotoxic. New treatments for amyloidosis may have an impact on kidney function, including drugs that target specific pathways involved in the disease. Tafamidis and diflunisal, which are TTR stabilizers, patisiran (RNA interference agent), and inotersen (antisense oligonucleotide inhibitor) have been shown to reduce TTR amyloid. Tafamidis and patisiran are medications that have reduced the progression of kidney disease in amyloidosis, but inotersen and diflunisal may damage kidney function.
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Morfino P, Aimo A, Franzini M, Vergaro G, Castiglione V, Panichella G, Limongelli G, Emdin M. Pathophysiology of Cardiac Amyloidosis. Heart Fail Clin 2024; 20:261-270. [PMID: 38844297 DOI: 10.1016/j.hfc.2024.02.002] [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: 06/09/2024]
Abstract
Amyloidosis refers to a heterogeneous group of disorders sharing common pathophysiological mechanisms characterized by the extracellular accumulation of fibrillar deposits consisting of the aggregation of misfolded proteins. Cardiac amyloidosis (CA), usually caused by deposition of misfolded transthyretin or immunoglobulin light chains, is an increasingly recognized cause of heart failure burdened by a poor prognosis. CA manifests with a restrictive cardiomyopathy which progressively leads to biventricular thickening, diastolic and then systolic dysfunction, arrhythmias, and valvular disease. The pathophysiology of CA is multifactorial and includes increased oxidative stress, mitochondrial damage, apoptosis, impaired metabolism, and modifications of intracellular calcium balance.
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Affiliation(s)
| | - Alberto Aimo
- Fondazione Toscana Gabriele Monasterio, via G. Moruzzi 1, 56124, Pisa, Italy; Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Maria Franzini
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Pisa, Italy
| | - Giuseppe Vergaro
- Fondazione Toscana Gabriele Monasterio, via G. Moruzzi 1, 56124, Pisa, Italy; Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Vincenzo Castiglione
- Fondazione Toscana Gabriele Monasterio, via G. Moruzzi 1, 56124, Pisa, Italy; Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Giorgia Panichella
- Department of Clinical and Experimental Medicine, Careggi University Hospital, Florence, Italy
| | - Giuseppe Limongelli
- Inherited and Rare Cardiovascular Disease Unit, Department of Translational Medical Sciences, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Michele Emdin
- Scuola Superiore Sant'Anna, Pisa, Italy; Fondazione Toscana Gabriele Monasterio, via G. Moruzzi 1, 56124, Pisa, Italy.
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3
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De Michieli L, Cipriani A, Iliceto S, Dispenzieri A, Jaffe AS. Cardiac Troponin in Patients With Light Chain and Transthyretin Cardiac Amyloidosis: JACC: CardioOncology State-of-the-Art Review. JACC CardioOncol 2024; 6:1-15. [PMID: 38510286 PMCID: PMC10950441 DOI: 10.1016/j.jaccao.2023.12.006] [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] [Received: 08/31/2023] [Revised: 12/27/2023] [Accepted: 12/29/2023] [Indexed: 03/22/2024] Open
Abstract
Cardiac amyloidosis (CA) is an infiltrative disease caused by amyloid fibril deposition in the myocardium; the 2 forms that most frequently involve the heart are amyloid light chain (AL) and amyloid transthyretin (ATTR) amyloidosis. Cardiac troponin (cTn) is the biomarker of choice for the detection of myocardial injury and is frequently found to be elevated in patients with CA, particularly with high-sensitivity assays. Multiple mechanisms of myocardial injury in CA have been proposed, including cytotoxic effect of amyloid precursors, interstitial amyloid fibril infiltration, coronary microvascular dysfunction, amyloid- and non-amyloid-related coronary artery disease, diastolic dysfunction, and heart failure. Regardless of the mechanisms, cTn values have relevant prognostic (and potentially diagnostic) implications in both AL and ATTR amyloidosis. In this review, the authors discuss the significant aspects of cTn biology and measurement methods, potential mechanisms of myocardial injury in CA, and the clinical application of cTn in the management of both AL and ATTR amyloidosis.
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Affiliation(s)
- Laura De Michieli
- Department of Cardiac, Thoracic and Vascular Sciences and Public Health, University of Padua, Padua, Italy
- Cardiovascular Department, Mayo Clinic and Medical School, Rochester, Minnesota, USA
| | - Alberto Cipriani
- Department of Cardiac, Thoracic and Vascular Sciences and Public Health, University of Padua, Padua, Italy
- Cardiology Unit, University Hospital of Padua, Padua, Italy
| | - Sabino Iliceto
- Department of Cardiac, Thoracic and Vascular Sciences and Public Health, University of Padua, Padua, Italy
- Cardiology Unit, University Hospital of Padua, Padua, Italy
| | | | - Allan S. Jaffe
- Cardiovascular Department, Mayo Clinic and Medical School, Rochester, Minnesota, USA
- Department of Laboratory Medicine and Pathology, Mayo Clinic and Medical School, Rochester, Minnesota, USA
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Apostolou EA, Fontrier AM, Efthimiadis GK, Kastritis E, Parissis J, Kanavos P. The patient pathway in ATTR-CM in Greece and how to improve it: A multidisciplinary perspective. Hellenic J Cardiol 2023; 73:73-80. [PMID: 37201632 DOI: 10.1016/j.hjc.2023.05.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 04/07/2023] [Accepted: 05/12/2023] [Indexed: 05/20/2023] Open
Abstract
Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underdiagnosed disease associated with high mortality rates and the patient journey is characterized by increased complexities. Accurate and timely diagnosis and prompt initiation of disease-modifying treatment constitute the contemporary unmet need in ATTR-CM. ATTR-CM diagnosis is characterized by considerable delays and high rates of misdiagnosis. The majority of patients present themselves to primary care physicians, internists, and cardiologists, and many have undergone repeated medical evaluations before an accurate diagnosis has been made. The disease is diagnosed mainly after the development of heart failure symptoms, reflecting a long course of missed opportunities before diagnosis and disease-modifying treatment initiation. Early referral to experienced centers ensures prompt diagnosis and therapy. Early diagnosis, better care coordination, acceleration of digital transformation and reference networks, encouragement of patient engagement, and implementation of rare disease registries are the key pillars to improve the ATTR-CM patient pathway and achieve important benefits in ATTR-CM outcomes.
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Affiliation(s)
- Efstratios A Apostolou
- Department of Health Policy and LSE Health, London School of Economics and Political Science, London, United Kingdom; Heart Failure Unit, Attikon University Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Anna-Maria Fontrier
- Department of Health Policy and LSE Health, London School of Economics and Political Science, London, United Kingdom
| | - Georgios K Efthimiadis
- 1(st) Cardiology Department, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Efstathios Kastritis
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, Athens, Greece
| | - John Parissis
- Heart Failure Unit, Attikon University Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Panos Kanavos
- Department of Health Policy and LSE Health, London School of Economics and Political Science, London, United Kingdom.
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Nakano T, Onoue K, Terada C, Terasaki S, Ishihara S, Hashimoto Y, Nakada Y, Nakagawa H, Ueda T, Seno A, Nishida T, Watanabe M, Hoshii Y, Hatakeyama K, Sakaguchi Y, Ohbayashi C, Saito Y. Transthyretin Amyloid Cardiomyopathy: Impact of Transthyretin Amyloid Deposition in Myocardium on Cardiac Morphology and Function. J Pers Med 2022; 12:jpm12050792. [PMID: 35629214 PMCID: PMC9147607 DOI: 10.3390/jpm12050792] [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: 03/11/2022] [Revised: 05/11/2022] [Accepted: 05/12/2022] [Indexed: 12/10/2022] Open
Abstract
Background: Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is increasingly being recognized as a cause of left ventricular (LV) hypertrophy (LVH) and progressive heart failure in elderly patients. However, little is known about the cardiac morphology of ATTR-CM and the association between the degree of TTR amyloid deposition and cardiac dysfunction in these patients. Methods: We studied 28 consecutive patients with ATTR-CM and analyzed the relationship between echocardiographic parameters and pathological features using endomyocardial biopsy samples. Results: The cardiac geometries of patients with ATTR-CM were mainly classified as concentric LVH (96.4%). The relative wall thickness, a marker of LVH, tended to be positively correlated with the degree of non-cardiomyocyte area. The extent of TTR deposition was positively correlated with enlargement of the non-cardiomyocyte area, and these were positively correlated with LV diastolic dysfunction. Additionally, the extent of the area containing TTR was positively correlated with the percentage of cardiomyocyte nuclei stained for 8-hydroxy-2′deoxyguanosine, a marker of reactive oxygen species (ROS). ROS accumulation in cardiomyocytes was positively correlated with LV systolic dysfunction. Conclusion: Patients with ATTR-CM mainly displayed concentric LVH geometry. TTR amyloid deposition was associated with cardiac dysfunction via increased non-cardiomyocyte area and ROS accumulation in cardiomyocytes.
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Affiliation(s)
- Tomoya Nakano
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
- Department of Cardiovascular Medicine, Yamato Takada Municipal Hospital, Yamato-Takada 635-8501, Nara, Japan
| | - Kenji Onoue
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
- Correspondence: ; Tel.: +81-744-22-3051
| | - Chiyoko Terada
- Department of Diagnostic Pathology, Nara Medical University, Kashihara 634-8521, Nara, Japan; (C.T.); (C.O.)
| | - Satoshi Terasaki
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Satomi Ishihara
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Yukihiro Hashimoto
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Yasuki Nakada
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Hitoshi Nakagawa
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Tomoya Ueda
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Ayako Seno
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Taku Nishida
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Makoto Watanabe
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Yoshinobu Hoshii
- Department of Diagnostic Pathology, Yamaguchi University Hospital, Ube 755-0046, Yamaguchi, Japan;
| | - Kinta Hatakeyama
- Department of Pathology, National Cerebral and Cardiovascular Center, Suita 564-8565, Osaka, Japan;
| | - Yasuhiro Sakaguchi
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
| | - Chiho Ohbayashi
- Department of Diagnostic Pathology, Nara Medical University, Kashihara 634-8521, Nara, Japan; (C.T.); (C.O.)
| | - Yoshihiko Saito
- Department of Cardiovascular Medicine, Nara Medical University, Kashihara 634-8521, Nara, Japan; (T.N.); (S.T.); (S.I.); (Y.H.); (Y.N.); (H.N.); (T.U.); (A.S.); (T.N.); (M.W.); (Y.S.); (Y.S.)
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Palmer C, Truong VT, Slivnick JA, Wolking S, Coleman P, Mazur W, Zareba KM. Atrial function and geometry differences in transthyretin versus immunoglobulin light chain amyloidosis: a cardiac magnetic resonance study. Sci Rep 2022; 12:140. [PMID: 34996915 PMCID: PMC8742089 DOI: 10.1038/s41598-021-03359-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 11/24/2021] [Indexed: 11/24/2022] Open
Abstract
To determine the differences in left atrial (LA) function and geometry assessed by cardiac magnetic resonance (CMR) between transthyretin (ATTR) and immunoglobulin light chain (AL) cardiac amyloidosis (CA). We performed a retrospective analysis of 54 consecutive patients (68.5% male, mean age 67 ± 11 years) with confirmed CA (24 ATTR, 30 AL) who underwent comprehensive CMR examinations. LA structural and functional assessment including LA volume, LA sphericity index, and LA strain parameters were compared between both subtypes. In addition, 15 age-matched controls were compared to all groups. Patients with ATTR-CA were older (73 ± 9 vs. 62 ± 10 years, p < 0.001) and more likely to be male (83.3% vs. 56.7%, p = 0.036) when compared to AL-CA. No significant difference existed in LA maximum volume and LA sphericity index between ATTR-CA and AL-CA. LA minimum volumes were larger in ATTR-CA when compared with AL-CA. There was a significant difference in LA function with worse strain values in ATTR vs AL: left atrial reservoir [7.4 (6.3–12.8) in ATTR vs. 13.8 (6.90–24.8) in AL, p = 0.017] and booster strains [3.6 (2.6–5.5) in ATTR vs. 5.2 (3.6–12.1) in AL, p = 0.039]. After adjusting for age, LA reservoir remained significantly lower in ATTR-CA compared to AL-CA (p = 0.03), but not LA booster (p = 0.16). We demonstrate novel differences in LA function between ATTR-CA and AL-CA despite similar LA geometry. Our findings of more impaired LA function in ATTR may offer insight into higher AF burden in these patients.
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Affiliation(s)
- Cassady Palmer
- The Christ Hospital Health Network, 2123 Auburn Ave, Ste 138, Cincinnati, OH, 45219, USA.
| | - Vien T Truong
- The Christ Hospital Health Network, 2123 Auburn Ave, Ste 138, Cincinnati, OH, 45219, USA.,The Lindner Research Center, Cincinnati, OH, USA
| | | | - Sarah Wolking
- The Christ Hospital Health Network, 2123 Auburn Ave, Ste 138, Cincinnati, OH, 45219, USA
| | - Paige Coleman
- The Christ Hospital Health Network, 2123 Auburn Ave, Ste 138, Cincinnati, OH, 45219, USA
| | - Wojciech Mazur
- The Christ Hospital Health Network, 2123 Auburn Ave, Ste 138, Cincinnati, OH, 45219, USA
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7
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Molecular Mechanisms of Cardiac Amyloidosis. Int J Mol Sci 2021; 23:ijms23010025. [PMID: 35008444 PMCID: PMC8744761 DOI: 10.3390/ijms23010025] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/18/2021] [Accepted: 12/18/2021] [Indexed: 12/22/2022] Open
Abstract
Cardiac involvement has a profound effect on the prognosis of patients with systemic amyloidosis. Therapeutic methods for suppressing the production of causative proteins have been developed for ATTR amyloidosis and AL amyloidosis, which show cardiac involvement, and the prognosis has been improved. However, a method for removing deposited amyloid has not been established. Methods for reducing cytotoxicity caused by amyloid deposition and amyloid precursor protein to protect cardiovascular cells are also needed. In this review, we outline the molecular mechanisms and treatments of cardiac amyloidosis.
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8
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Chandrashekar P, Desai AK, Trachtenberg BH. Targeted treatments of AL and ATTR amyloidosis. Heart Fail Rev 2021; 27:1587-1603. [PMID: 34783948 DOI: 10.1007/s10741-021-10180-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/12/2021] [Indexed: 12/22/2022]
Abstract
The therapeutic landscape for cardiac amyloidosis is rapidly evolving. In the last decade, our focus has shifted from dealing with the inevitable complications of continued extracellular infiltration of amyloid fibrils to earlier identification of these patients with prompt initiation of targeted therapy to prevent further deposition. Although much of the focus on novel targeted therapies is within the realm of transthyretin amyloidosis, light chain amyloidosis has benefited due to an overlap particularly in the final common pathway of fibrillogenesis and extraction of amyloid fibrils from the heart. Here, we review the targeted therapeutics for transthyretin and light chain amyloidosis. For transthyretin amyloidosis, the list of current and future therapeutics continues to evolve; and therefore, it is crucial to become familiar with the underlying mechanistic pathways of the disease. Although targeted therapeutic choices in AL amyloidosis are largely driven by the hematology team, the cardiac adverse effect profiles of these therapies, particularly in those with advanced amyloidosis, provide an opportunity for early recognition to prevent decompensation and can help inform recommendations regarding therapy changes when required.
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Affiliation(s)
- Pranav Chandrashekar
- Amyloidosis Center, Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA
| | - Anish K Desai
- Department of Medicine, Oregon Health & Science University, Portland, OR, USA
| | - Barry H Trachtenberg
- Methodist DeBakey Heart and Vascular Center, Houston, TX, USA. .,Cardio-Oncology and Cardiac Amyloidosis Program, Advanced Heart Failure Fellowship Program, Methodist DeBakey Heart and Vascular Centers, J.C. Walter Transplant Center, Houston, USA.
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9
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Dittloff KT, Iezzi A, Zhong JX, Mohindra P, Desai TA, Russell B. Transthyretin amyloid fibrils alter primary fibroblast structure, function, and inflammatory gene expression. Am J Physiol Heart Circ Physiol 2021; 321:H149-H160. [PMID: 34018852 DOI: 10.1152/ajpheart.00073.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Age-related wild-type transthyretin amyloidosis (wtATTR) is characterized by systemic deposition of amyloidogenic fibrils of misfolded transthyretin (TTR) in the connective tissue of many organs. In the heart, this leads to cardiac dysfunction, which is a significant cause of age-related heart failure. The hypothesis tested is that TTR affects cardiac fibroblasts in ways that may contribute to fibrosis. When primary cardiac fibroblasts were cultured on TTR-deposited substrates, the F-actin cytoskeleton was disorganized, focal adhesion formation was decreased, and nuclear shape was flattened. Fibroblasts had faster collective and single-cell migration velocities on TTR-deposited substrates. In addition, fibroblasts cultured on microposts with TTR deposition had reduced attachment and increased proliferation above untreated. Transcriptomic and proteomic analyses of fibroblasts grown on glass covered with TTR showed significant upregulation of inflammatory genes after 48 h, indicative of progression in TTR-based diseases. Together, results suggest that TTR deposited in tissue extracellular matrix may affect the structure, function, and gene expression of cardiac fibroblasts. As therapies for wtATTR are cost-prohibitive and only slow disease progression, better understanding of cellular maladaptation may elucidate novel therapeutic targets.NEW & NOTEWORTHY Transthyretin (TTR) cardiac amyloidosis involves deposition of fibrils of misfolded TTR in the aging human heart, leading to cardiac dysfunction and heart failure. Our novel in vitro studies show that TTR fibrils alter primary cardiac fibroblast cytoskeletal and nuclear structure and focal adhesion formation. Furthermore, both fibrillar and tetrameric TTR significantly increased cellular migration velocity and caused upregulation of inflammatory genes determined by transcriptomic RNA and protein analysis. These findings may suggest new therapeutic approaches.
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Affiliation(s)
- Kyle T Dittloff
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Antonio Iezzi
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
| | - Justin X Zhong
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, San Francisco, California.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California
| | - Priya Mohindra
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, San Francisco, California.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California
| | - Tejal A Desai
- UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, San Francisco, California.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California.,Department of Bioengineering, University of California, Berkeley, California
| | - Brenda Russell
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
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10
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Abstract
Often considered a rare disease, cardiac amyloidosis is increasingly recognized by practicing clinicians. The increased rate of diagnosis is in part due the aging of the population and increasing incidence and prevalence of cardiac amyloidosis with advancing age, as well as the advent of noninvasive methods using nuclear scintigraphy to diagnose transthyretin cardiac amyloidosis due to either variant or wild type transthyretin without a biopsy. Perhaps the most important driver of the increased awareness is the elucidation of the biologic mechanisms underlying the pathogenesis of cardiac amyloidosis which have led to the development of several effective therapies with differing mechanisms of actions. In this review, the mechanisms underlying the pathogenesis of cardiac amyloidosis due to light chain (AL) or transthyretin (ATTR) amyloidosis are delineated as well as the rapidly evolving therapeutic landscape that has emerged from a better pathophysiologic understanding of disease development.
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Affiliation(s)
- Jan M. Griffin
- Division of Cardiology, Cardiovascular Research Laboratory
for the Elderly, Columbia University Irving Medical Center, New York, NY
| | - Hannah Rosenblum
- Division of Cardiology, Cardiovascular Research Laboratory
for the Elderly, Columbia University Irving Medical Center, New York, NY
| | - Mathew S. Maurer
- Division of Cardiology, Cardiovascular Research Laboratory
for the Elderly, Columbia University Irving Medical Center, New York, NY
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11
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Oligomerization Profile of Human Transthyretin Variants with Distinct Amyloidogenicity. Molecules 2020; 25:molecules25235698. [PMID: 33287192 PMCID: PMC7730986 DOI: 10.3390/molecules25235698] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/05/2020] [Accepted: 11/24/2020] [Indexed: 02/08/2023] Open
Abstract
One of the molecular hallmarks of amyloidoses is ordered protein aggregation involving the initial formation of soluble protein oligomers that eventually grow into insoluble fibrils. The identification and characterization of molecular species critical for amyloid fibril formation and disease development have been the focus of intense analysis in the literature. Here, using photo-induced cross-linking of unmodified proteins (PICUP), we studied the early stages of oligomerization of human transthyretin (TTR), a plasma protein involved in amyloid diseases (ATTR amyloidosis) with multiple clinical manifestations. Upon comparison, the oligomerization processes of wild-type TTR (TTRwt) and several TTR variants (TTRV30M, TTRL55P, and TTRT119M) clearly show distinct oligomerization kinetics for the amyloidogenic variants but a similar oligomerization mechanism. The oligomerization kinetics of the TTR amyloidogenic variants under analysis showed a good correlation with their amyloidogenic potential, with the most amyloidogenic variants aggregating faster (TTRL55P > TTRV30M > TTRwt). Moreover, the early stage oligomerization mechanism for these variants involves stepwise addition of monomeric units to the growing oligomer. A completely different behavior was observed for the nonamyloidogenic TTRT119M variant, which does not form oligomers in the same acidic conditions and even for longer incubation times. Thorough characterization of the initial steps of TTR oligomerization is critical for better understanding the origin of ATTR cytotoxicity and developing novel therapeutic strategies for the treatment of ATTR amyloidosis.
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12
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Structural Stabilization of Human Transthyretin by Centella asiatica (L.) Urban Extract: Implications for TTR Amyloidosis. Biomolecules 2019; 9:biom9040128. [PMID: 30934952 PMCID: PMC6523946 DOI: 10.3390/biom9040128] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/21/2019] [Accepted: 03/21/2019] [Indexed: 02/07/2023] Open
Abstract
Transthyretin is responsible for a series of highly progressive, degenerative, debilitating, and incurable protein misfolding disorders known as transthyretin (TTR) amyloidosis. Since dissociation of the homotetrameric protein to its monomers is crucial in its amyloidogenesis, stabilizing the native tetramer from dissociating using small-molecule ligands has proven a viable therapeutic strategy. The objective of this study was to determine the potential role of the medicinal herb Centella asiatica on human transthyretin (huTTR) amyloidogenesis. Thus, we investigated the stability of huTTR with or without a hydrophilic fraction of C. asiatica (CAB) against acid/urea-mediated denaturation. We also determined the influence of CAB on huTTR fibrillation using transmission electron microscopy. The potential binding interactions between CAB and huTTR was ascertained by nitroblue tetrazolium redox-cycling and 8-anilino-1-naphthalene sulfonic acid displacement assays. Additionally, the chemical profile of CAB was determined by liquid chromatography quadruple time-of-flight mass spectrometry (HPLC-QTOF-MS). Our results strongly suggest that CAB bound to and preserved the quaternary structure of huTTR in vitro. CAB also prevented transthyretin fibrillation, although aggregate formation was unmitigated. These effects could be attributable to the presence of phenolics and terpenoids in CAB. Our findings suggest that C. asiatica contains pharmaceutically relevant bioactive compounds which could be exploited for therapeutic development against TTR amyloidosis.
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Ami D, Mereghetti P, Leri M, Giorgetti S, Natalello A, Doglia SM, Stefani M, Bucciantini M. A FTIR microspectroscopy study of the structural and biochemical perturbations induced by natively folded and aggregated transthyretin in HL-1 cardiomyocytes. Sci Rep 2018; 8:12508. [PMID: 30131519 PMCID: PMC6104026 DOI: 10.1038/s41598-018-30995-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 08/09/2018] [Indexed: 02/07/2023] Open
Abstract
Protein misfolding and aggregation are associated with a number of human degenerative diseases. In spite of the enormous research efforts to develop effective strategies aimed at interfering with the pathogenic cascades induced by misfolded/aggregated peptides/proteins, the necessary detailed understanding of the molecular bases of amyloid formation and toxicity is still lacking. To this aim, approaches able to provide a global insight in amyloid-mediated physiological alterations are of importance. In this study, we exploited Fourier transform infrared microspectroscopy, supported by multivariate analysis, to investigate in situ the spectral changes occurring in cultured intact HL-1 cardiomyocytes exposed to wild type (WT) or mutant (L55P) transthyretin (TTR) in native, or amyloid conformation. The presence of extracellular deposits of amyloid aggregates of WT or L55P TTR, respectively, is a key hallmark of two pathological conditions, known as senile systemic amyloidosis and familial amyloid polyneuropathy. We found that the major effects, associated with modifications in lipid properties and in the cell metabolic/phosphorylation status, were observed when natively folded WT or L55P TTR was administered to the cells. The effects induced by aggregates of TTR were milder and in some cases displayed a different timing compared to those elicited by the natively folded protein.
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Affiliation(s)
- Diletta Ami
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy.
| | - Paolo Mereghetti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy
| | - Manuela Leri
- Department of Neuroscience, Psychology, Area of Medicine and Health of the Child of the University of Florence, Viale Pieraccini, 6, 50139, Florence, Italy.,Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, 50134, Florence, Italy
| | - Sofia Giorgetti
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, Viale Taramelli 3/B, 27100, Pavia, Italy
| | - Antonino Natalello
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy
| | - Silvia Maria Doglia
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milano, Italy
| | - Massimo Stefani
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, 50134, Florence, Italy.,Interuniversity Center for the Study of Neurodegenerative Diseases (CIMN), Florence, Italy
| | - Monica Bucciantini
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, 50134, Florence, Italy. .,Interuniversity Center for the Study of Neurodegenerative Diseases (CIMN), Florence, Italy.
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14
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Saelices L, Sievers SA, Sawaya MR, Eisenberg DS. Crystal structures of amyloidogenic segments of human transthyretin. Protein Sci 2018; 27:1295-1303. [PMID: 29626847 PMCID: PMC6032358 DOI: 10.1002/pro.3420] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 12/24/2022]
Abstract
Amyloid diseases are characterized by the deposition of proteins in the form of amyloid fibrils, in organs that eventually fail. The development of effective drug candidates follows from the understanding of the molecular processes that lead to protein aggregation. Here, we study amyloidogenic segments of transthyretin (TTR). TTR is a transporter of thyroxine and retinol in the blood and cerebrospinal fluid. When mutated and/or as a result of aging, TTR aggregates into amyloid fibrils that accumulate in organs such as the heart. Recently, we reported two amyloidogenic segments that drive amyloid aggregation. Here, we report the crystal structure of another six amyloidogenic segments of TTR. We found that the segments from the C-terminal region of TTR form in-register steric-zippers with highly-interdigitated, wet interfaces, whereas the β-strand B from the N-terminal region of TTR forms an out-of-register assembly, previously associated with oligomeric formation. Our results contribute fundamental information for understanding the mechanism of aggregation of TTR.
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Affiliation(s)
- Lorena Saelices
- Departments of Biological Chemistry and Chemistry and Biochemistry, Molecular Biology Institute, Box 951570, UCLAHoward Hughes Medical Institute, UCLA‐DOE InstituteLos AngelesCalifornia90095‐1570
| | - Stuart A. Sievers
- Departments of Biological Chemistry and Chemistry and Biochemistry, Molecular Biology Institute, Box 951570, UCLAHoward Hughes Medical Institute, UCLA‐DOE InstituteLos AngelesCalifornia90095‐1570
- Present address:
Kite Pharma IncSanta MonicaCalifornia.
| | - Michael R. Sawaya
- Departments of Biological Chemistry and Chemistry and Biochemistry, Molecular Biology Institute, Box 951570, UCLAHoward Hughes Medical Institute, UCLA‐DOE InstituteLos AngelesCalifornia90095‐1570
| | - David S. Eisenberg
- Departments of Biological Chemistry and Chemistry and Biochemistry, Molecular Biology Institute, Box 951570, UCLAHoward Hughes Medical Institute, UCLA‐DOE InstituteLos AngelesCalifornia90095‐1570
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15
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Sumi-Akamaru H, Eto M, Yamauchi A, Uehara T, Kakuda K, Obayashi K, Kato S, Naka T, Mochizuki H. Evidence that glial cells attenuate G47R transthyretin accumulation in the central nervous system. Neuropathology 2017; 38:11-21. [PMID: 28960480 DOI: 10.1111/neup.12412] [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: 06/07/2017] [Revised: 08/03/2017] [Accepted: 08/03/2017] [Indexed: 11/29/2022]
Abstract
Amyloidogenic protein forms amyloid aggregations at membranes leading to dysfunction of amyloid clearance and amyloidosis. Glial cells function in the clearance and degradation of amyloid β (Aβ) in the brain. This study aimed to clarify the reason why amyloid transthyretin (ATTR) rarely accumulates in the CNS. We pathologically analyzed the relationship between amyloid deposition with basement membranes or glial cells in a rare case of ATTR leptomeningeal amyloidosis. In addition, we compared the cytotoxicity of ATTR G47R, the amyloidosis-causing mutation in the case studied (n = 1), and Aβ in brains from patients with cerebral amyloid angiopathy (n = 6). In the subarachnoid space of the ATTR G47R case, most amyloids accumulated at the components of basement membranes. On the CNS surface, ATTR accumulations were retained by astrocytic end feet. In areas where glial end feet enveloped ATTR, ubiquitination and micro-vacuolation of ATTR was evident. The colocalization of GFAP and ubiquitin was also evident. The accumulation of ATTR G47R in the CNS was negatively correlated with the prevalence of astrocytes. Quantitatively, amyloid deposits along the vessels were mostly partial in cerebral Aβ angiopathy cases and nearly complete along the basement membrane in the ATTR G47R case. The vascular expressions of type IV collagen and smooth muscle actin were severely reduced in areas with ATTR G47R deposition, but not in areas with Aβ deposition. The vascular protein level recovered in the ATTR G47R case when vessels entered into areas of parenchyma that were rich in astrocytes. In addition, the strong interactions between the transthyretin variant and basement membranes may have led to dysfunction of transthyretin clearance and leptomeningeal amyloidosis. The present study was the first to show that glial cells may attenuate G47R transthyretin accumulation in the CNS.
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Affiliation(s)
- Hisae Sumi-Akamaru
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Masaki Eto
- Department of Neurology, Higashiosaka City Medical Center, Higashi-Osaka, Japan
| | - Amane Yamauchi
- Department of Diagnostic Pathology, Higashiosaka City Medical Center, Higashi-Osaka, Japan
| | - Takuya Uehara
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Japan.,Department of Neurology, Higashiosaka City Medical Center, Higashi-Osaka, Japan
| | - Keita Kakuda
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Japan.,Department of Neurology, Higashiosaka City Medical Center, Higashi-Osaka, Japan
| | - Konen Obayashi
- Department of Morphological and Physiological Sciences, Graduate School of Health Sciences, Kumamoto University, Kumamoto, Japan
| | - Shinsuke Kato
- Division of Neuropathology, Department of Pathology, Tottori University Faculty of Medicine, Yonago, Japan
| | - Takashi Naka
- Department of Neurology, Higashiosaka City Medical Center, Higashi-Osaka, Japan
| | - Hideki Mochizuki
- Department of Neurology, Graduate School of Medicine, Osaka University, Suita, Japan
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16
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Sartiani L, Bucciantini M, Spinelli V, Leri M, Natalello A, Nosi D, Maria Doglia S, Relini A, Penco A, Giorgetti S, Gerace E, Mannaioni G, Bellotti V, Rigacci S, Cerbai E, Stefani M. Biochemical and Electrophysiological Modification of Amyloid Transthyretin on Cardiomyocytes. Biophys J 2017; 111:2024-2038. [PMID: 27806283 DOI: 10.1016/j.bpj.2016.09.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 07/26/2016] [Accepted: 09/06/2016] [Indexed: 12/26/2022] Open
Abstract
Transthyretin (TTR) amyloidoses are familial or sporadic degenerative conditions that often feature heavy cardiac involvement. Presently, no effective pharmacological therapy for TTR amyloidoses is available, mostly due to a substantial lack of knowledge about both the molecular mechanisms of TTR aggregation in tissue and the ensuing functional and viability modifications that occur in aggregate-exposed cells. TTR amyloidoses are of particular interest regarding the relation between functional and viability impairment in aggregate-exposed excitable cells such as peripheral neurons and cardiomyocytes. In particular, the latter cells provide an opportunity to investigate in parallel the electrophysiological and biochemical modifications that take place when the cells are exposed for various lengths of time to variously aggregated wild-type TTR, a condition that characterizes senile systemic amyloidosis. In this study, we investigated biochemical and electrophysiological modifications in cardiomyocytes exposed to amyloid oligomers or fibrils of wild-type TTR or to its T4-stabilized form, which resists tetramer disassembly, misfolding, and aggregation. Amyloid TTR cytotoxicity results in mitochondrial potential modification, oxidative stress, deregulation of cytoplasmic Ca2+ levels, and Ca2+ cycling. The altered intracellular Ca2+ cycling causes a prolongation of the action potential, as determined by whole-cell recordings of action potentials on isolated mouse ventricular myocytes, which may contribute to the development of cellular arrhythmias and conduction alterations often seen in patients with TTR amyloidosis. Our data add information about the biochemical, functional, and viability alterations that occur in cardiomyocytes exposed to aggregated TTR, and provide clues as to the molecular and physiological basis of heart dysfunction in sporadic senile systemic amyloidosis and familial amyloid cardiomyopathy forms of TTR amyloidoses.
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Affiliation(s)
- Laura Sartiani
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy; Center of Molecular Medicine, University of Florence, Florence, Italy
| | - Monica Bucciantini
- Department of Biomedical, Experimental and Clinical Sciences "Mario Serio,", University of Florence, Florence, Italy; Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, Florence, Italy.
| | - Valentina Spinelli
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy; Center of Molecular Medicine, University of Florence, Florence, Italy
| | - Manuela Leri
- Department of Biomedical, Experimental and Clinical Sciences "Mario Serio,", University of Florence, Florence, Italy
| | - Antonino Natalello
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Daniele Nosi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Silvia Maria Doglia
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | | | - Amanda Penco
- Department of Physics, University of Genoa, Genoa, Italy
| | - Sofia Giorgetti
- Department of Molecular Medicine, Institute of Biochemistry, University of Pavia, Pavia, Italy
| | - Elisabetta Gerace
- Department of Health Science, University of Florence, Florence, Italy
| | - Guido Mannaioni
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Vittorio Bellotti
- Department of Molecular Medicine, Institute of Biochemistry, University of Pavia, Pavia, Italy; Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, Division of Medicine, University College London, London, United Kingdom
| | - Stefania Rigacci
- Department of Biomedical, Experimental and Clinical Sciences "Mario Serio,", University of Florence, Florence, Italy
| | - Elisabetta Cerbai
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy; Center of Molecular Medicine, University of Florence, Florence, Italy; Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, Florence, Italy
| | - Massimo Stefani
- Department of Biomedical, Experimental and Clinical Sciences "Mario Serio,", University of Florence, Florence, Italy; Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, Florence, Italy
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17
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Sapp V, Jain M, Liao R. Viewing Extrinsic Proteotoxic Stress Through the Lens of Amyloid Cardiomyopathy. Physiology (Bethesda) 2017; 31:294-9. [PMID: 27252164 DOI: 10.1152/physiol.00047.2015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Proteotoxicity refers to toxic stress caused by misfolded proteins of extrinsic or intrinsic origin and plays an integral role in the pathogenesis of cardiovascular diseases. Herein, we provide an overview of the current understanding of mechanisms underlying proteotoxicity and its contribution in the pathogenesis of amyloid cardiomyopathy.
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Affiliation(s)
- Valerie Sapp
- Departments of Medicine & Pharmacology, University of California San Diego, San Diego, California; and
| | - Mohit Jain
- Departments of Medicine & Pharmacology, University of California San Diego, San Diego, California; and
| | - Ronglih Liao
- Division of Genetics and Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
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18
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Buxbaum JN, Johansson J. Transthyretin and BRICHOS: The Paradox of Amyloidogenic Proteins with Anti-Amyloidogenic Activity for Aβ in the Central Nervous System. Front Neurosci 2017; 11:119. [PMID: 28360830 PMCID: PMC5350149 DOI: 10.3389/fnins.2017.00119] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 02/27/2017] [Indexed: 01/19/2023] Open
Abstract
Amyloid fibrils are physiologically insoluble biophysically specific β-sheet rich structures formed by the aggregation of misfolded proteins. In vivo tissue amyloid formation is responsible for more than 30 different disease states in humans and other mammals. One of these, Alzheimer's disease (AD), is the most common form of human dementia for which there is currently no definitive treatment. Amyloid fibril formation by the amyloid β-peptide (Aβ) is considered to be an underlying cause of AD, and strategies designed to reduce Aβ production and/or its toxic effects are being extensively investigated in both laboratory and clinical settings. Transthyretin (TTR) and proteins containing a BRICHOS domain are etiologically associated with specific amyloid diseases in the CNS and other organs. Nonetheless, it has been observed that TTR and BRICHOS structures are efficient inhibitors of Aβ fibril formation and toxicity in vitro and in vivo, raising the possibility that some amyloidogenic proteins, or their precursors, possess properties that may be harnessed for combating AD and other amyloidoses. Herein, we review properties of TTR and the BRICHOS domain and discuss how their abilities to interfere with amyloid formation may be employed in the development of novel treatments for AD.
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Affiliation(s)
- Joel N Buxbaum
- Department of Molecular and Experimental Medicine, The Scripps Research InstituteLa Jolla, CA, USA; Scintillon InstituteSan Diego, CA, USA
| | - Jan Johansson
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences, and Society (NVS), Center for Alzheimer Research, Karolinska Institutet Huddinge, Sweden
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19
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Iakovleva I, Begum A, Brännström K, Wijsekera A, Nilsson L, Zhang J, Andersson PL, Sauer-Eriksson AE, Olofsson A. Tetrabromobisphenol A Is an Efficient Stabilizer of the Transthyretin Tetramer. PLoS One 2016; 11:e0153529. [PMID: 27093678 PMCID: PMC4836675 DOI: 10.1371/journal.pone.0153529] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 03/30/2016] [Indexed: 01/15/2023] Open
Abstract
Amyloid formation of the human plasma protein transthyretin (TTR) is associated with several human disorders, including familial amyloidotic polyneuropathy (FAP) and senile systemic amyloidosis. Dissociation of TTR's native tetrameric assembly is the rate-limiting step in the conversion into amyloid, and this feature presents an avenue for intervention because binding of an appropriate ligand to the thyroxin hormone binding sites of TTR stabilizes the native tetrameric assembly and impairs conversion into amyloid. The desired features for an effective TTR stabilizer include high affinity for TTR, high selectivity in the presence of other proteins, no adverse side effects at the effective concentrations, and a long half-life in the body. In this study we show that the commonly used flame retardant tetrabromobisphenol A (TBBPA) efficiently stabilizes the tetrameric structure of TTR. The X-ray crystal structure shows TBBPA binding in the thyroxine binding pocket with bromines occupying two of the three halogen binding sites. Interestingly, TBBPA binds TTR with an extremely high selectivity in human plasma, and the effect is equal to the recently approved drug tafamidis and better than diflunisal, both of which have shown therapeutic effects against FAP. TBBPA consequently present an interesting scaffold for drug design. Its absorption, metabolism, and potential side-effects are discussed.
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Affiliation(s)
- Irina Iakovleva
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Afshan Begum
- Department of Chemistry, Umeå University, Umeå, Sweden
| | | | - Alexandra Wijsekera
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Lina Nilsson
- Department of Chemistry, Umeå University, Umeå, Sweden
| | - Jin Zhang
- Department of Chemistry, Umeå University, Umeå, Sweden
| | | | | | - Anders Olofsson
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
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20
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Repositioning tolcapone as a potent inhibitor of transthyretin amyloidogenesis and associated cellular toxicity. Nat Commun 2016; 7:10787. [PMID: 26902880 PMCID: PMC4766415 DOI: 10.1038/ncomms10787] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 01/20/2016] [Indexed: 02/05/2023] Open
Abstract
Transthyretin (TTR) is a plasma homotetrameric protein implicated in fatal systemic amyloidoses. TTR tetramer dissociation precedes pathological TTR aggregation. Native state stabilizers are promising drugs to treat TTR amyloidoses. Here we repurpose tolcapone, an FDA-approved molecule for Parkinson's disease, as a potent TTR aggregation inhibitor. Tolcapone binds specifically to TTR in human plasma, stabilizes the native tetramer in vivo in mice and humans and inhibits TTR cytotoxicity. Crystal structures of tolcapone bound to wild-type TTR and to the V122I cardiomyopathy-associated variant show that it docks better into the TTR T4 pocket than tafamidis, so far the only drug on the market to treat TTR amyloidoses. These data indicate that tolcapone, already in clinical trials for familial amyloid polyneuropathy, is a strong candidate for therapeutic intervention in these diseases, including those affecting the central nervous system, for which no small-molecule therapy exists.
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