Showing papers in "Amyloid in 1997"
TL;DR: Quantitative fiuorometry revealed that extension of fAβ2M proceeded by a pseudo-first order exponential increase as measured by the fluorescence of ThT, which is essential to build up a kinetic experimental system to analyze fA β2M formation in vitro.
Abstract: β2-microglobulin (β2M) is a major structural component of dialysis-related amyloid fibrils (fAβ2M). In order to make clear the mechanism of fAβ2M deposition in vivo, as well as to assess the effects of several biological factors on it, it is essential to build up a kinetic experimental system to analyze fAβ2M formation in vitro. We first determined the optimum conditions for quantitative jluorometry of fAβ2M with thioflavine T (ThT). Optimum fluorescence measurements of fAβ2M were obtained at the excitation and emission wavelengths of 455 nm and 485 nm, respectively, with the reaction mixture containing 3 μM ThT and 50 mM of glycine-NaOH buffeer, pH 8.5. We then focused our study on the extension phase of fAβ2M formation in vitro. When fAβ2M were incubated with monomeric β2M, the extension of fAβ2M was observed with electron microscopy. Quantitative fiuorometry revealed that: (a) extension of fAβ2M proceeded by a pseudo-first order exponential increase as measured by the fluorescence of ThT; (b) the rate ...
218 citations
207 citations
TL;DR: An easy, efficient trifluoroacetic acid (TFA) pretreatment method that renders the Aβ easily soluble both in aqueous, buffered solutions and in organic solvents such as hexafluoroisopropanol (HFIP) or dimethylsulfoxide (DMSO).
Abstract: Major problems exist with pharmacological and biophysical studies of the synthetic β(1-42) peptide, in that the results often lack reproducibility. The starting aggregation states and structures of the various synthetic commercial lots appear to vary, resulting in signijicant lot-to-lot variability. We describe here an easy, efficient trifluoroacetic acid (TFA) pretreatment method that renders the Aβ easily soluble both in aqueous, buffered solutions and in organic solvents such as hexafluoroisopropanol (HFIP) or dimethylsulfoxide (DMSO). The TFA treated Aβ exhibits the properties of monomeric, random coil structures and lacks pre-aggregated material that can act as seeds in fibrilization assays, thus reducing the batch to batch variation. In addition, nuclear magnetic resonance (NMR) spectra recorded in deuterated TFA allow measurement of the peptide purity that is not obtainable with other analytical methods.
114 citations
TL;DR: The present study reports optimized fixation and processing methods for the light and electron microscopic immunohistochemical characterization of tissue amyloid characterization in abdominal fat aspirates and tissue biopsy samples from different organs from 36 patients.
Abstract: The present study reports our optimized fixation and processing methods for the light and electron microscopic immunohistochemical characterization of tissue amyloid. The study involved a series of 25 abdominal fat aspirates and of 11 tissue biopsy samples from different organs from 36 patients. We tested a short fixation and processing method and a series of enzymatic, acidic and physical (microwave oven) pretreatments on paraffin slides for light microscopy, Congo red stain and immunohistochemistry. Microwave antigen retrieval provided the highest enhancement for both Congo red stain and immunohistochemical reactions with all tested antibodies; formic acid also gave good results, but tissue morphology may have been altered. Immunoelectron microscopy provided evidence of fibril accumulation and immunoreactivity in both mixed (double immunoreactivity) and non-mixed forms, along with information on the relative amount of immunoreaction for the two components in mixed amyloid deposits; the technique also yi...
68 citations
TL;DR: Solubilization of bound complement proteins and immunoblotting reveal that aggregated Aβ1–42 binds larger amounts of complement proteins C1q, C4, C3, C5 and C6, than Aggregated A β1–40, Aβ 1–28 and Aβ 17–43, and the binding of C3 requires complement activation, unlike CIq and C4.
Abstract: Complement activation and its deposition on β-amyloid plaques in Alzheimer's Disease (AD) brains correlates with the development of AD dementia Results from immunocytochemical studies suggest that the appearance of complement activation in AD brains results in part from a direct interaction with the β-amyloid (Aβ) peptide Aβ–42, the major peptide of β-amyloid plaques To study this possibility, we exposed aggregated Aβ of different lengths to complement present in normal human serum (NHS) in vitro NHS contains two pathways for complement activation, the classical and alternative Solubilization of bound complement proteins and immunoblotting reveal that aggregated Aβ1–42 binds larger amounts of complement proteins C1q, C4, C3, C5 and C6, than aggregated Aβ1–40, Aβ1–28 and Aβ 17–43 The binding of C3, unlike CIq and C4, requires complement activation In NHS, C3 binding to aggregated Aβ1–42 occurs by both the alternative path-way and, to a lesser extent, the classical pathway The activation of C3 by bot
41 citations
TL;DR: A novel chicken model in which reactive (AA) joint amyloidosis arises ajier a single injection of Enterococcus faecalis isolated from jield outbreaks of reactive amyloids arthropathy in domestic fowl is described.
Abstract: The present report describes a novel chicken model in which reactive (AA) joint amyloidosis arises ajier a single injection of Enterococcus faecalis isolated from jield outbreaks of reactive amyloid arthropathy in domestic fowl. All six week old brown layer pullets injected intravenously with 109 or 109 colony forming units developed reactive amyloid arthropathy. Amyloid masses were also present in internal organs. The first articular amyloid deposits were observed 5 days after injection. in internal organs, deposits were encountered fiom day 13 onwards. on intra-articular injection, amyloid arthropathy developed particularly in Ihe target joint and in the internal organs.This model ofAA amyloid arthropathy may contribute in future studies to unravel the pathogenesis of the tissue predilection of amyloid deposition and 05 amyloid arthropathy in general.
35 citations
33 citations
TL;DR: Proteoglycans and the extracellular matrix, as they relate to amyloidosis, are reviewed.
Abstract: Amyloidosis comprises numerous diseases that are characterized by the deposition of insoluble amyloid fibrils in the extracellular matrix in one or more of virtually any organ and tissue of the body. The general nature of amyloid deposits is still not completely defined, however, the presence of fibrillar structures is unquestioned, and the fibrils themselves are derived from proteins. The nature of the nonfibrillar constituents of amyloid deposits is still obscure, but it is becoming evident that proteins such as the amyloid P component, apoE and components derived from the extracellular matrix itself, especially basement membranes, seem to represent ubiquitous components of amyloid deposits, irrespective of the biochemical nature of the fibril-forming protein. The extracellular matrix components found in amyloid include proteoglycans, glycosaminoglycans, glycoproteins and extracellular matrix growth factors. Here, proteoglycans and the extracellular matrix, as they relate to amyloidosis, are reviewed.
32 citations
TL;DR: To the authors' knowledge this is the first report of discordant symptoms in monozygotic twin brothers, 55 years of age, which might indicate that environmental factors are of importance for the onset of FAP symptoms.
Abstract: Two monozygotic twin brothers, 55 years of age, are carriers of the TTR Met 30 gene. Twin no. 1 had onset of typical FAP symptoms seven years ago, while twin no. 2 is absolutely healthy. The twins have the same educational background, are working in the same industry and are living in the same area. The progress of symptoms in twin no. 1 was rather rapid with polyneuropathy, gastrointestinal and heart symptoms. Liver transplantation was per-formed in twin no. 1 in 1993, with a successful result. The discordance of FAP symptoms in identical twins might indicate that environmental factors are of importance for the onset of FAP symptoms. The possible importance of environmental factors is indicated by a population study made in the same area. The TTR Met 30 gene carrier frequency is 1.6 per cent, while the frequency of FAP patients in the same area is only 0.05 per cent, indicating a gene penetrance of only about 5 per cent. To our knowledge this is the first report of discordant symptoms in monozygotic twin...
30 citations
TL;DR: HDL and HDLsaa binding and intemalisation experiments were performed with cultured, cholesterol-laden murine MpH using either native or colloidal gold-labelled HDL and HDLSaa, and visualized either directly by light and electronmicroscopy, or by immunocytochemical means.
Abstract: Serum amyloid A (SAA), an acute phase protein found primarily on high density lipoproteins (HDLsaa), is the precursor protein of AA-amyloidosis. Though extensivly studied, the pathway by which SAA bound to HDL becomes deposited as a fibril protein in AA-amyloidosis, is unknown. Macrophages (Mo) have been implicated in the pathogen-esis of AA amyloidosis and are known to bind, endocytose and retro-endocytose HDL. Studies were therefore performed to examine whether HDLsaa is handled in a manner similar to HDLHDL and HDLsaa binding and intemalisation experiments were performed with cultured, cholesterol-laden murine MpH using either native or colloidal gold-labelled HDL and HDLsaa, and visualized either directly by light and electronmicroscopy, or by immunocytochemical means. Pre-treatment of MpH with heparinase examined the potential importance of membrane-bound glycosaminoglycans on the binding and uptake of HDL and HDLsaaThe binding of HDL and HDLsaa by MpH depended on culture conditions. Short-term cultu...
27 citations
TL;DR: From the previously characterized amyloid positive tissues, Western blotting of both isolated fibrils prepared by solubilization in distilled water and the material extracted in acetonitrile from the same specimens yielded identical low molecular weight proteins (>28kDa) immunoreactive with only one of the 4 antibodies tested.
Abstract: The heterogeneity of the amyloidoses requires the determination of the chemical type of amyloid protein deposited in tissues. in the present study of 15 diagnostic biopsy specimens classified as light chain amyloid, nonamyloid light chain disease, amyloid A and transthyretin amyloid by immunojluorescence microscopy, the residual frozen tissues were independently analyzed by immunochemical methods. The tissue deposits were extracted in aqueous 20% acetonitrile containing 0.1% trlfluoroacetic acid and the extracted material subjected to Western blotting. Similarly analyzed were 9 control amyloid negative and 6 amyloid positive tissues. From the previously characterized amyloid positive tissues, Western blotting of both isolated fibrils prepared by solubilization in distilled water and the material extracted in acetonitrile from the same specimens yielded identical low molecular weight proteins (>28kDa) immunoreactive with only one of the 4 antibodies tested, whereas the control amyloid negative tissue extra...
TL;DR: periodic nausea and vomiting ceased and other autonomic symptoms including orthostatic hypotension, abnormal bowel movements and dysuria were also improving soon after PLT, and further progression of FAP symptoms was observed in one severely disabled patient with a 7 year-history of this disease.
Abstract: Partial liver transplantation using a graft from a living donor (PLT) has been carried out for children with incurable hepatic disorders. We have extended this technique to 5 adult patients (4 female and 1 male) with familial amyloid polyneuropathy (FAP). All were proven to have a TTR Met30 mutation. Four of these 5 patients are alive 5 to 28 months after operation, and 3 patients with a shorter duration of illness (less than jive years) showed remarkable clinical improvement. Periodic nausea and vomiting ceased and other autonomic symptoms including orthostatic hypotension, abnormal bowel movements and dysuria were also improving soon after PLT. Somatic motor and sensory neuropathic symptoms tended to improve very gradually. on the other hand. further progression of FAP symptoms was observed in one severely disabled patient with a 7 year-history of this disease. One other patient with a similar condition died 3 months after PLT. The donors who consisted of 2 sisters and 3 husbands recovered without compl...
TL;DR: The data suggest that following endocytosis of exogenous murine apoSAA/SAA2, the animals undergoing amyloidosis may be processed in the endosomes-lysosomes (EL).
Abstract: Murine ApoSAA3 is synthesized and secreted by activated monocytoid cells. in contrast, these cells have been implicated in the endocytosis of exogenous murine apoSAA/SAA2 and in AA amyloid formation. The implication is that endocytosed apoSAA1/SAA2 may be processed in the endosomes-lysosomes (EL). Here we show the topographic relationship between apoSAA3 and apoSAA1/SAA2 and identify apoSAA1 /SAA2 and their derivatives in peritoneal macrophages from alveolar hydatid cyst infected mice undergoing amyloidosis. Confocal microscopy localized apoSAA1/SAA2 exclusively to the EL whereas apoSAA3 generally had a non-vesicular cytoplasmic distribution. Immunoblotting of the macrophage cytoplasmic fractions, regardless of the duration of the infection, identified pre-dominantly two ~5 and 12 kDa C-terminus cleaved apoSAA1/SAA2 derivatives which resembled in molecular mass the tissue AA Immunoblotting of the infected mouse sera did not reveal any apoSAA1/SAA2 derivatives. These data suggest that following endocytosis...
TL;DR: The biochemical characterization of two amyloid proteins, including their partial amino terminal sequence, isolated from localized forms of ureteral amyfoidosis provide additional evidence for the association betweenAmyloidogenic Ig light chains and localized, tumor-like forms of amyloidsosis.
Abstract: We present the biochemical characterization of two amyloid proteins, including their partial amino terminal sequence, isolated from localized forms of ureteral amyfoidosis. The major component of amyloid NAv extracted from milligram quantities of biopsy tissue, had a molecular mass of 16 kDa and the 20 first amino acids showed homology to immunoglobulin (Ig) light chain of the subgroup λ II. In addition, amyloid P component co-purified with amyloid NA V as determined by Western blot analysis. Amyloid MAI was extracted from formalin fixed, paraffin embedded tissue. It had a molecular mass of 14 kDa and its amino terminal sequence (17 steps) revealed homology to Ig light chain of the subgroup λ III. These results provide additional evidence for the association between amyloidogenic Ig light chains and localized, tumor-like forms of amyloidosis. Moreover, the two simple methods presented here may facilitate the characterization of amyloid proteins from small samples of frozen tissue and rare specimens stored...
TL;DR: It is suggested that apolipoprotein E is a common constituent of amyloid fibrils in patients undergoing chronic hemodialysis with and without dialysis-related amyloidsosis, and in healthy controls.
Abstract: We previously developed a monoclonal antibody recognizing apolipoprotein E in all types of systemic amyloidosis, including dialysis-related amyloidosis. This suggests that apolipoprotein E is a common constituent of amyloid fibrils. in the present study, we analyzed the serum level of apolipoprotein E, the apolipoprotein E phenotypes and the corresponding allele frequencies in 97 patients undergoing chronic hemodialysis with and without dialysis-related amyloidosis, and in 173 healthy controls. The serum concentrations of apolipoprotein E in the patients with amyloidosis did not differ from those in the other hemodialysis patients and in healthy controls. However, the apolipoprotein E3/N phenotype was significantly more common (p<0.05) in the group with amyloidosis (32.0%) than in the healthy controls (13.9%). The frequency of the apolipoprotein E4 allele was significantly greater (p<0.01) in the group with amyloidosis (0.22) than in the group without amyloidosis (0.08) or in healthy controls (0.09). Resu...
TL;DR: The pathogenesis of β2M amyloidosis is reconsidered in light of recently published data regarding advanced glycation end products (AGE), and available and potential treatments for this condition are discussed.
Abstract: β2-microglobulin (β2M) amyloidosis is a disabling disease that affects patients with long-term chronic renal failure but not individuals with normal renal function. It is an ideal model for study of the amyloid diseases because a defined population is at risk for the development of this condition, its clinical manifestations evolve predictably over time, and it ultimately occurs in the majority of patients who have received long-term dialysis therapy. The clinical features of β2M amyloidosis are reviewed, highlighting the systemic nature of this disease. The various techniques available to diagnose this condition are described. The pathogenesis of β2M amyloidosis is reconsidered in light of recently published data regarding advanced glycation end products (AGE). Available and potential treatments for this condition are also discussed.
TL;DR: The complete amino acid sequence of cheetah protein AA is determined (positions 1–90) and these positions conform to positions 2–83 of human proteins apoSAA/AA.
Abstract: Systemic AA amyloidosis is relatively uncommon in domestic cats, but a relatively high prevalence of this form of amyloidosis has been documented in Abyssinian cats and, most recently, in captive cheetahs. These cats thus provide an opportunity to identify and compare amino acid sequence differences in the respective AA proteins that may potentially affect the amyloidogenic process. In this study we determined the complete amino acid sequence of cheetah protein AA (positions 1–90). These positions conform to positions 2–83 of human proteins apoSAA/AA in that the respective cat proteins are N-terminally one residue shorter than the human protein and have an eight amino acid insert between residues conforming to positions 69 and 70 of human apoSAA/AA. Comparison of the protein AA sequence of the cheetah with confirmed protein AA sequences from Abyssinian and/or domestic short-haired (DSH) cats revealed amino acid variations at positions 2, 30, 43, 49, 54, 69e, 69g and 81 (using human numbering). AA proteins...
TL;DR: In this article, specific proteoglycans as potential causative agents and relevant targets for therapeutic intervention in Alzheimer's disease and other amyloidosis were discussed, and the authors proposed a set of targets for treatment.
Abstract: (1997). Specific proteoglycans as potential causative agents and relevant targets for therapeutic intervention in Alzheimer's disease and other amyloidosis. Amyloid: Vol. 4, No. 2, pp. 135-141.
TL;DR: A clinical study and the analysis of transthyretin abnormality were performed on a family with familial amyloid polyneuropathy that had recently been found in China, and it is suggested that mass spectrometry system is a useful procedure for screening variant TTRs in the sera of large populations.
Abstract: A clinical study and the analysis of transthyretin (TTR) abnormality were performed on a family with familial amyloid polyneuropathy (FAP) that had recently been found in China. Fourteen members over four generations were affected and their clinical pictures were consistent with those of type I FAP Using a matrix-assisted laser desorption ion-izatiod time- oS-flight mass spectrometry system, a TTR variant which possibly corresponded to Met 30 TTR was easily identified in the sera of patients and then, Met 30 TTR gene abnormality was confirmed on PCR-RFLP analysis. It is suggested that mass spectrometry system is a useful procedure for screening variant TTRs in the sera of large populations.
TL;DR: Subdivision of the S-JCA patient group, into those with and without reactive amyloidosis, reveals a highly significant co-segregation of theSAA2a2 allele with the amyloidsotic condition.
Abstract: Restriction fragment length polymorphisms of the serum amyloid A, gene have been used to distinguish three alleles:-a1, a2 and β The relative frequencies of these alleles in patients with systemic onset juvenile chronic arthritis (S-JCA) match those in healthy control individuals Subdivision of the S-JCA patient group, into those with and without reactive amyloidosis, reveals a highly significant co-segregation of the SAA2a2 allele with the amyloidotic condition
TL;DR: The in vitro formed fibrils from synthetic peptides represent parts of the human TTR sequence that are mostly in the β-strands in the tertiary structure of TTR and expose a highly fibrillogenic sequence, possibly important for in vivofibrillogenesis.
Abstract: The fibril forming capacity of synthetic peptides representing parts of the human TTR sequence was investigated. The in vitro formed fibrils were studied with electron microscopy and with polarized light after staining with Congo red dye and also compared with fibrils formed in vitro from normal TTR and fibrils extracted from amyloid deposits from a patient with senile systemic amyloidosis. Most of the synthetic peptides that were fibrillogenic in this study represent parts of the TTR sequence that are mostly in the β-strands in the tertiary structure of TTR. A peptide corresponding to the α-helix was also strongly fibrillogenic in vitro as was a peptide representing the DE-loop. in senile systemic amyloidosis and in familial amyloidotic polyneuropathy the fibrils contain C-terminal fragments of TTR starting just before the D strand. The cleavage of the TTR molecule thus exposes a highly fibrillogenic sequence, possibly important for in vivo fibrillogenesis.The in vitro formed fibrils from synthetic pepti...
TL;DR: Hemodynamic instability with low systolic systemic blood pressure was found during the preanhepatic phase, unrelated to surgical procedure, and volume loading or vasoactive drugs had only modest effects.
Abstract: Familial amyloidotic polyneuropathy is a new indication for liver transplantation. Severe cardiovascular disturbances including severe bradyarrhythmias are well known complications to FAP, during anesthesia and operation.Twenty-seven patients with FAP type I (TTR Met30) were followed during and after transplantation. Mean duration of disease was 5 years and mean modified body mass index (mBMI) 690 (normal >700). At pretransplant evaluation, six patients had A V-conduction disturbances, 13 echocardiographic signs of amyloid deposits, five had orthostatic reactions and two had permanent pacemakers.In 14 patients. hemodynamic instability with low systolic systemic blood pressure was found during the preanhepatic phase, unrelated to surgical procedure. Volume loading or vasoactive drugs had only modest effects. Preoperative cardiac findings did not correlate with hemodynamic instability. A temporary pacemaker was introduced in 19 patients, but in only one of these patients did the pacemaker actively pace the ...
TL;DR: It is reported that Aβ1-42 stimulates a parallel increase in the cellular levels of APLP2 in cultured HCSM cells, which suggest a common regulatory mechanism for increased levels of H CSM cellular AJPP and APLP 2 in response to pathologic Aβ 1-42 induced stress.
Abstract: The amyloid β-protein (Aβ) which accumulates in cerebral vascular and senile plaque deposits in the brains of patients with Alzheimer's disease (AD) is proteolytically derived from a larger precursor protein, the amyloid β-protein precursor (AβPP). AβPP is a member of a multigene family which includes amyloid precursor-like protein 2 (APLP2). Recently, we showed that Aβ1-42, but not the shorter Aβ1-40 induces cellular levels of AβPP in degenerating cultured human cerebrovascular smooth muscle (HCSM) cells. Here we report that Aβ1-42 stimulates a parallel increase in the cellular levels of APLP2 in cultured HCSM cells. in contrast, the levels of smooth muscle cell α-actin or total cellular protein did not appreciably change. These findings suggest a common regulatory mechanism for increased levels of HCSM cellular AJPP and APLP2 in response to pathologic Aβ1-42 induced stress.
TL;DR: This study measured, using ELISA or bioassay methodology, fluctuation in concentration of the circulating cytokines tumor necrosis factor (TNF) and interleukin 6 (IL-6), and the acute phase proteins serum amyloid A (apoSAA) and C-reactive protein (CRP), in five septic patients, during a one-week period starting from the day of diagnosis.
Abstract: This study measured, using ELISA or bioassay methodology, fluctuation in concentration of the circulating cytokines tumor necrosis factor (TNF) and interleukin 6 (IL-6), and the acute phase proteins serum amyloid A (apoSAA) and C-reactive protein (CRP), in five septic patients, during a one-week period starting from the day of diagnosis. All had consistently detectable levels of circulating TNF (range of peak values, 0.6-13.6 ng/ml); two also had high IL-6 levels, while the remaining three had detectable levels only at some time points (range of peak values, 105-31j pg/ ml). TNF concentrations fluctuated during the observation period, in some cases with a biphasic temporal pattern. TNF and IL-6 levels were undetectable (below 30 and 100 pg/ml, respectively) in the control population with our assuys12.ApoSAA concentrations in these patients (range of peak values, 65-975 fig/ml) were correlated with TNF and with high CRP concentrations (range of peak values, 7-329 pg/ ml). ApoSAA concentrations ranged from ...
TL;DR: A Dutch kindred with transthyretin Cys 114 related familial amyloidotic polyneuropathy is reported, and the discovery of early involvement of the heart is of great concern and of special relevance to the optimal timing for liver transplantation.
Abstract: A Dutch kindred with transthyretin Cys 114 related familial amyloidotic polyneuropathy is reported. The jnding of early involvement of the heart is of great concern and of special relevance to the optimal timing for liver transplantation. to date, the variant had only been reported to be present in Japan. The variant was identlfied by PCR DNA ampllfication, single strand conformation polymorphism analysis and DNA sequence analysis. Total transthyretin serum levels in 6 Cys 114 patients (median 115 mg/l, range 70-150) were found to be significantly lower than in 12 Met 30 patients (median 325 mg/l, range 160-590) (p<0.0001), which suggests rapid breakdown andor transformation into amyloid andor decreased synthesis.
TL;DR: A captive, 9 year old female cheetah with progressive signs of chronic renal failure was euthanized and Histologic studies of the kidney revealed severe glomerular and medullary amyloidosis.
Abstract: A captive, 9 year old female cheetah (Acinonyxjubatus) with progressive signs of chronic renal failure was euthanized Histologic studies of the kidney revealed severe glomerular and medullary amyloidosis. The amyloid stained positivelv with Congo red and showed green birefringence under polarized light. Based on potassium permanganate sensitivity and the immunohistochemical reaction with monoclonal antibodies, the renal amyloid was classlfied as AA. Amyloid was also deposited in the liver and heart. Elec-trophoresis of heart and kidney tissue showed two protein bands reflecting serum amyloid A. This is the first detailed report of amyloidosis leading to renal failure in a highly endangered species.
TL;DR: This study reveals the first silent mutation on the TTR gene : Ala108, a tetrameric protein synthesized by the liver and the choroid plexus that binds thyroxine and retinol-binding protein.
Abstract: Transthyretin (TTR) is a 55kDa tetrameric protein synthesized by the liver and the choroid plexus that binds thyroxine and retinol-binding protein. More than fifty mutations have been identified in the TTR gene, the majority of them associated with hereditary amyloidosis1. This study reveals the first silent mutation on the TTR gene : Ala108.