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Swiss Medical Weekly Feb 2024Systemic amyloidoses are rare protein-folding diseases with heterogeneous, often nonspecific clinical presentations. To better understand systemic amyloidoses and to...
AIMS OF THE STUDY
Systemic amyloidoses are rare protein-folding diseases with heterogeneous, often nonspecific clinical presentations. To better understand systemic amyloidoses and to apply state-of-the-art diagnostic pathways and treatment, the interdisciplinary Amyloidosis Network was founded in 2013 at University Hospital Zurich. In this respect, a registry was implemented to study the characteristics and life expectancy of patients with amyloidosis within the area covered by the network. Patient data were collected retrospectively for the period 2005-2014 and prospectively from 2015 onwards.
METHODS
Patients aged 18 years or older diagnosed with any subtype of systemic amyloidosis were eligible for inclusion if they were treated in one of the four referring centres (Zurich, Chur, St Gallen, Bellinzona). Baseline data were captured at the time of diagnosis. Follow-up data were assessed half-yearly for the first two years, then annually.
RESULTS
Between January 2005 and March 2020, 247 patients were screened, and 155 patients with confirmed systemic amyloidosis were included in the present analysis. The most common amyloidosis type was light-chain (49.7%, n = 77), followed by transthyretin amyloidosis (40%, n = 62) and amyloid A amyloidosis (5.2%, n = 8). Most patients (61.9%, n = 96) presented with multiorgan involvement. Nevertheless, single organ involvement was seen in all types of amyloidosis, most commonly in amyloid A amyloidosis (75%, n = 6). The median observation time of the surviving patients was calculated by the reverse Kaplan-Meier method and was 3.29 years (95% confidence interval [CI] 2.33-4.87); it was 4.87 years (95% CI 3.14-7.22) in light-chain amyloidosis patients and 1.85 years (95% CI 1.48-3.66) in transthyretin amyloidosis patients, respectively. The 1-, 3- and 5-year survival rates were 87.0% (95% CI 79.4-95.3%), 68.5% (95% CI 57.4-81.7%) and 66.0% (95% CI 54.6-79.9%) respectively for light-chain amyloidosis patients and 91.2% (95% CI 83.2-99.8%), 77.0% (95% CI 63.4-93.7%) and 50.6% (95% CI 31.8-80.3%) respectively for transthyretin amyloidosis patients. There was no significant difference between the two groups (p = 0.81).
CONCLUSION
During registry set-up, a more comprehensive work-up of our patients suffering mainly from light-chain amyloidosis and transthyretin amyloidosis was implemented. Survival rates were remarkably high and similar between light-chain amyloidosis and transthyretin amyloidosis, a finding which was noted in similar historic registries of international centres. However, further studies are needed to depict morbidity and mortality as the amyloidosis landscape is changing rapidly.
Topics: Humans; Amyloid Neuropathies, Familial; Amyloidosis; Registries; Retrospective Studies; Serum Amyloid A Protein; Switzerland; Adult
PubMed: 38579306
DOI: 10.57187/s.3485 -
International Journal of Molecular... Mar 2024Trigonelline (TRG) is a natural polar hydrophilic alkaloid that is found in many plants such as green coffee beans and fenugreek seeds. TRG potentially acts on multiple... (Review)
Review
Trigonelline (TRG) is a natural polar hydrophilic alkaloid that is found in many plants such as green coffee beans and fenugreek seeds. TRG potentially acts on multiple molecular targets, including nuclear factor erythroid 2-related factor 2 (Nrf2), peroxisome proliferator-activated receptor γ, glycogen synthase kinase, tyrosinase, nerve growth factor, estrogen receptor, amyloid-β peptide, and several neurotransmitter receptors. In this review, we systematically summarize the pharmacological activities, medicinal properties, and mechanistic actions of TRG as a potential therapeutic agent. Mechanistically, TRG can facilitate the maintenance and restoration of the metabolic homeostasis of glucose and lipids. It can counteract inflammatory constituents at multiple levels by hampering pro-inflammatory factor release, alleviating inflammatory propagation, and attenuating tissue injury. It concurrently modulates oxidative stress by the blockage of the detrimental Nrf2 pathway when autophagy is impaired. Therefore, it exerts diverse therapeutic effects on a variety of pathological conditions associated with chronic metabolic diseases and age-related disorders. It shows multidimensional effects, including neuroprotection from neurodegenerative disorders and diabetic peripheral neuropathy, neuromodulation, mitigation of cardiovascular disorders, skin diseases, diabetic mellitus, liver and kidney injuries, and anti-pathogen and anti-tumor activities. Further validations are required to define its specific targeting molecules, dissect the underlying mechanistic networks, and corroborate its efficacy in clinical trials.
Topics: Humans; NF-E2-Related Factor 2; Alkaloids; Diabetes Mellitus; Oxidative Stress
PubMed: 38542359
DOI: 10.3390/ijms25063385 -
The Journal of Biological Chemistry May 2024Aggregation of leukocyte cell-derived chemotaxin 2 (LECT2) causes ALECT2, a systemic amyloidosis that affects the kidney and liver. Previous studies established that...
Aggregation of leukocyte cell-derived chemotaxin 2 (LECT2) causes ALECT2, a systemic amyloidosis that affects the kidney and liver. Previous studies established that LECT2 fibrillogenesis is accelerated by the loss of its bound zinc ion and stirring/shaking. These forms of agitation create heterogeneous shear conditions, including air-liquid interfaces that denature proteins, that are not present in the body. Here, we determined the extent to which a more physiological form of mechanical stress-shear generated by fluid flow through a network of narrow channels-drives LECT2 fibrillogenesis. To mimic blood flow through the kidney, where LECT2 and other proteins form amyloid deposits, we developed a microfluidic device consisting of progressively branched channels narrowing from 5 mm to 20 μm in width. Shear was particularly pronounced at the branch points and in the smallest capillaries. Aggregation was induced within 24 h by shear levels that were in the physiological range and well below those required to unfold globular proteins such as LECT2. EM images suggested the resulting fibril ultrastructures were different when generated by laminar flow shear versus shaking/stirring. Importantly, results from the microfluidic device showed the first evidence that the I40V mutation accelerated fibril formation and increased both the size and the density of the aggregates. These findings suggest that kidney-like flow shear, in combination with zinc loss, acts in combination with the I40V mutation to trigger LECT2 amyloidogenesis. These microfluidic devices may be of general use for uncovering mechanisms by which blood flow induces misfolding and amyloidosis of circulating proteins.
Topics: Humans; Amyloid; Intercellular Signaling Peptides and Proteins; Kidney; Stress, Mechanical; Amyloid Neuropathies; Shear Strength; Renal Plasma Flow; Protein Aggregates
PubMed: 38537700
DOI: 10.1016/j.jbc.2024.107231 -
Revista de La Facultad de Ciencias... Mar 2024The most common form of hereditary amyloidosis is associated with variants of transthyretin (TTR). Familial amyloidosis polyneuropathy associated with variants of TTR...
INTRODUCTION
The most common form of hereditary amyloidosis is associated with variants of transthyretin (TTR). Familial amyloidosis polyneuropathy associated with variants of TTR (FAP-TTR) is an infrequent, multisystemic disease, with predominant involvement of the peripheral nervous system. More than 130 pathogenic variants have been identified so far and most of them are amyloidogenic, being Val30Met the most frequently described.
CASE REPORT
A 74 year-old male was evaluated for progressive decreased sensitivity and associated loss of strength in four limbs in the previous two years, needing assistance for walking. Areflexia, bilateral tibialis anterior and gastrocnemius atrophy, bilateral anesthesia and apalesthesia were found in lower limbs. Bilateral hypoesthesia was reported in upper limbs. No painful dysesthesia, hyperalgesia or allodynia were found. DNA sequencing of the TTR gene led to the detection of the variant c.186G>C in heterozygous state. The resulting variant (Glu62Asp), located in the critical functional domain, has not been published before.
CONCLUSION
The importance of considering late onset, sporadic FAP-TTR as a differential diagnosis of cryptogenic polyneuropathy is highlighted.
Topics: Aged; Humans; Male; Amyloid Neuropathies, Familial; Prealbumin
PubMed: 38537102
DOI: 10.31053/1853.0605.v81.n1.40992 -
Circulation Journal : Official Journal... Jun 2024The prevalence of transthyretin amyloid cardiomyopathy (ATTR-CM) in atrial fibrillation (AF) patients remains unclear. We explored the efficacy of computed...
Efficacy of Computed Tomography-Based Evaluation of Myocardial Extracellular Volume Combined With Red Flags for Early Screening of Concealed Cardiac Amyloidosis in Patients With Atrial Fibrillation.
BACKGROUND
The prevalence of transthyretin amyloid cardiomyopathy (ATTR-CM) in atrial fibrillation (AF) patients remains unclear. We explored the efficacy of computed tomography-based myocardial extracellular volume (CT-ECV) combined with red flags for the early screening of concealed ATTR-CM in AF patients undergoing catheter ablation.Methods and Results: Patients referred for AF ablation at Oita University Hospital were prescreened using the red-flag signs defined by echocardiographic or electrocardiographic findings, medical history, symptoms, and blood biochemical findings. Myocardial CT-ECV was quantified in red flag-positive patients using routine pre-AF ablation planning cardiac CT with the addition of delayed-phase cardiac CT scans. Patients with high (>35%) ECV were evaluated using technetium pyrophosphate (Tc-PYP) scintigraphy. A cardiac biopsy was performed during the planned AF ablation procedure if Tc-PYP scintigraphy was positive. Between June 2022 and June 2023, 342 patients were referred for AF ablation. Sixty-seven (19.6%) patients had at least one of the red-flag signs. Myocardial CT-ECV was evaluated in 57 patients because of contraindications to contrast media, revealing that 16 patients had high CT-ECV. Of these, 6 patients showed a positive Tc-PYP study, and 6 patients were subsequently diagnosed with wild-type ATTR-CM via cardiac biopsy and genetic testing.
CONCLUSIONS
CT-ECV combined with red flags could contribute to the systematic early screening of concealed ATTR-CM in AF patients undergoing catheter ablation.
Topics: Humans; Atrial Fibrillation; Male; Female; Aged; Middle Aged; Amyloid Neuropathies, Familial; Cardiomyopathies; Catheter Ablation; Myocardium; Tomography, X-Ray Computed; Early Diagnosis
PubMed: 38522901
DOI: 10.1253/circj.CJ-23-0948 -
Cardiology and Therapy Jun 2024Transthyretin amyloidosis (ATTR) is a progressive, heterogeneous rare disease manifesting as ATTR polyneuropathy (ATTR-PN), ATTR cardiomyopathy (ATTR-CM), or a mixed...
INTRODUCTION
Transthyretin amyloidosis (ATTR) is a progressive, heterogeneous rare disease manifesting as ATTR polyneuropathy (ATTR-PN), ATTR cardiomyopathy (ATTR-CM), or a mixed phenotype. Tafamidis meglumine (20 mg po qd) is approved in some markets to delay neurologic progression in ATTR-PN, while high-dose tafamidis (80/61 mg po qd) is approved worldwide to reduce cardiovascular mortality and cardiovascular-related hospitalization in ATTR-CM. The objective of this study was to assess the real-world benefit of high-dose tafamidis for delaying neurologic progression in patients with mixed-phenotype variant ATTR-CM (ATTRv-CM).
METHODS
This exploratory, retrospective, observational cohort study evaluated anonymized electronic medical records and included adult patients with mixed-phenotype ATTRv-CM treated with high-dose tafamidis for at least 6 months. Neurologic assessments included the Medical Research Council (MRC) Scale for Muscle Strength, Neuropathy Impairment Score (NIS) muscle weakness subscale, and Polyneuropathy Disability (PND) instrument. Modified body mass index (mBMI) was also assessed.
RESULTS
Patients (N = 10) started tafamidis treatment an average of 3.8 months after diagnosis, with an average treatment duration of 20.8 months. Seven of 10 patients demonstrated normal muscle strength on the MRC scale throughout the study, and 9 of 10 patients had no decline in muscle strength during the post-treatment period. The NIS muscle weakness subscale score was ≤ 60 for all patients in the study at all time points, suggesting normal function to mild impairment. Six of 10 patients had no change in walking capacity as measured by the PND instrument at pre- and post-assessments, while one-third of patients had a decrease in PND stage (signaling improvement) from pre- to post-assessment. mBMI remained relatively stable throughout the study.
CONCLUSION
This is the first real-world study to demonstrate the potential value of high-dose tafamidis for delaying neurologic disease progression in patients with mixed-phenotype ATTRv-CM. The findings underscore the importance of multidisciplinary assessment for patients with ATTR amyloidosis.
TRIAL REGISTRATION
ClinicalTrials.gov: NCT05139680.
PubMed: 38521883
DOI: 10.1007/s40119-024-00362-9 -
Archivos de Cardiologia de Mexico 2024Aortic stenosis (AS) is currently the most common valvular disease, with an estimated prevalence of over 4% in octogenarians.
BACKGROUND
Aortic stenosis (AS) is currently the most common valvular disease, with an estimated prevalence of over 4% in octogenarians.
OBJECTIVE
To describe the prevalence of moderate-severe aortic stenosis (AS) in patients with wild type transthyretin amyloidosis (ATTRwt). Also, describe the clinical features, echocardiographic characteristics and clinical evolution.
METHOD
Retrospective cohort of patients with diagnosis of ATTRwt, belonging to Hospital Italiano de Buenos Aires Institutional Amyloidosis Registry, from 30/11/2007 to 31/05/2021. Patients follow up was carried out through the institution clinical history. The prevalence of moderate-severe AE was estimated and presented as a percentage with its 95% confidence interval (95% CI). The characteristics were compared by groups according to whether or not they had moderate-severe AS.
RESULTS
104 patients with ATTRwt were included. Median follow up was 476 days [interquartile range: 192-749]. Moderate-severe AS prevalence at the ATTRwt time of diagnosis was 10.5% (n = 11; 95% CI: 5-18%). The median age of patients with AS moderate-severe at the time of diagnosis of ATTRwt was 86 years [78-91] and the male sex predominated (82%). Most of the patients had a history of heart failure (n = 8) and atrial fibrillation (n = 8) prior to the diagnosis of ATTRwt. Most of the patients were subclassified as low flow low gradient severe AS group (n = 7). Four patients underwent some intervention on the aortic valve. During follow-up, 5 patients (46%) were hospitalized for decompensated heart failure and 4 (36%) died.
CONCLUSIONS
In our cohort, the coexistence of both pathologies had a similar prevalence as reported in the international literature. It was an elderly population with a high percentage of atrial fibrillation and history of heart failure. Most of the patients presented with severe AS with low flow low gradient.
Topics: Aged, 80 and over; Humans; Male; Aged; Retrospective Studies; Atrial Fibrillation; Prevalence; Amyloid Neuropathies, Familial; Heart Failure; Aortic Valve Stenosis
PubMed: 38507302
DOI: 10.24875/ACM.22000074 -
The Israel Medical Association Journal... Mar 2024Cardiac amyloidosis (CA) is characterized by the extracellular deposition of misfolded protein in the heart. Precise identification of the amyloid type is often...
BACKGROUND
Cardiac amyloidosis (CA) is characterized by the extracellular deposition of misfolded protein in the heart. Precise identification of the amyloid type is often challenging, but critical, since the treatment and prognosis depend on the disease form and the type of deposited amyloid. Coexistence of clinical conditions such as old age, monoclonal gammopathy, chronic inflammation, or peripheral neuropathy in a patient with cardiomyopathy creates a differential diagnosis between the major types of CA: amyloidosis light chains (AL), amyloidosis transthyretin (ATTR) and amyloidosis A (AA).
OBJECTIVES
To demonstrate the utility of the Western blotting (WB)-based amyloid typing method in patients diagnosed with cardiac amyloidosis where the type of amyloid was not obvious based on the clinical context.
METHODS
Congo red positive endomyocardial biopsy specimens were studied in patients where the type of amyloid was uncertain. Amyloid proteins were extracted and identified by WB. Mass spectrometry (MS) of the electrophoretically resolved protein-in-gel bands was used for confirmation of WB data.
RESULTS
WB analysis allowed differentiation between AL, AA, and ATTR in cardiac biopsies based on specific immunoreactivity of the electrophoretically separated proteins and their characteristic molecular weight. The obtained results were confirmed by MS.
CONCLUSIONS
WB-based amyloid typing method is cheaper and more readily available than the complex and expensive gold standard techniques such as MS analysis or immunoelectron microscopy. Notably, it is more sensitive and specific than the commonly used immunohistochemical techniques and may provide an accessible diagnostic service to patients with amyloidosis in Israel.
Topics: Humans; Amyloidosis; Amyloid; Amyloidogenic Proteins; Cardiomyopathies; Blotting, Western; Amyloid Neuropathies, Familial; Prealbumin
PubMed: 38493325
DOI: No ID Found -
Scientific Reports Mar 2024Increasing evidence suggests that gut microbiota alterations are related to development and phenotypes of many neuropsychiatric diseases. Here, we evaluated the fecal...
Increasing evidence suggests that gut microbiota alterations are related to development and phenotypes of many neuropsychiatric diseases. Here, we evaluated the fecal microbiota and its clinical correlates in patients with hereditary transthyretin amyloidosis (ATTRv) and polyneuropathy. Fecal microbiota from 38 ATTRv patients and 39 age-matched controls was analyzed by sequencing 16S V3-V4 ribosomal RNA, and its relationships with clinical characteristics of polyneuropathy and cardiomyopathy were explored. The familial amyloidotic polyneuropathy stage was stage I, II, and III in 13, 18, and 7 patients. Tc-PYP SPECT showed a visual score of 2 in 15 and 3 in 21 patients. The gut microbiota of ATTRv patients showed higher alpha diversity (ASV richness and Shannon effective numbers) and dissimilar beta diversity compared to controls. Relative abundance of microbiota was dominated by Firmicutes and decreased in Bacteroidetes in ATTRv patients than in controls. Patients with more myocardial amyloid deposition were associated with increased alpha diversity, and the abundance of Clostridia was significantly correlated with pathophysiology of polyneuropathy in ATTRv patients. These findings demonstrated alterations in the gut microbiota, especially Firmicutes, in ATTRv. The association between altered microbiota and phenotypes of cardiomyopathy and polyneuropathy might suggest potential contributions of gut microbiota to ATTRv pathogenesis.
Topics: Humans; Amyloid Neuropathies, Familial; Cardiomyopathies; Firmicutes; Gastrointestinal Microbiome; Polyneuropathies; RNA, Ribosomal, 16S
PubMed: 38486098
DOI: 10.1038/s41598-024-56984-5 -
Journal of the American College of... Mar 2024Cardiac amyloidosis is increasingly recognized as a treatable form of heart failure. Highly effective specific therapies have recently become available for the 2 most... (Review)
Review
Cardiac amyloidosis is increasingly recognized as a treatable form of heart failure. Highly effective specific therapies have recently become available for the 2 most frequent forms of cardiac amyloidosis: immunoglobulin light chain amyloidosis and transthyretin (ATTR) amyloidosis. Nevertheless, initiation of specific therapies requires recognition of cardiac amyloidosis and appropriate characterization of the amyloid type. Although noninvasive diagnosis is possible for ATTR cardiac amyloidosis, histological demonstration and typing of amyloid deposits is still required for a substantial number of patients with ATTR and in all patients with light chain amyloidosis and other rarer forms of cardiac amyloidosis. Amyloid histological typing can be performed using different techniques: mass spectrometry, immunohistochemistry, and immunoelectron microscopy. This review describes which patients require histological confirmation of cardiac amyloidosis along with when and how to type amyloid deposits in histologic specimens. Furthermore, it covers the characteristics and limitations of the different typing methods that are available in clinical practice.
Topics: Humans; Plaque, Amyloid; Amyloidosis; Amyloid; Heart Failure; Immunohistochemistry; Amyloidogenic Proteins; Prealbumin; Amyloid Neuropathies, Familial; Cardiomyopathies
PubMed: 38479957
DOI: 10.1016/j.jacc.2024.01.010