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Sample records for serum amyloid protein

  1. Human serum amyloid A. Three hepatic mRNAs and the corresponding proteins in one person.

    OpenAIRE

    Kluve-Beckerman, B; Dwulet, F.E.; Benson, M. D.

    1988-01-01

    Serum amyloid A protein (SAA) is a major acute-phase protein in humans and most other mammals. In addition, it is the serum precursor of the major protein constituent of reactive amyloid fibrils. Sequence analyses have identified a number of polymorphic forms of human SAA and amyloid A protein (AA), but the question of the number of genes encoding SAA in the human has not been addressed. In addition, there are insufficient data to predict whether one form of SAA predisposes to amyloid fibril ...

  2. Serum amyloid A protein in amyloidosis, rheumatic, and neoplastic diseases

    International Nuclear Information System (INIS)

    Serum levels of amyloid protein A (SAA) have been shown to be elevated in different types of amyloidosis and in rheumatic diseases by radioimmunoassay using 125 iodine labeled AA and anti-AA. SAA levels were elevated in both primary and secondary amyloidosis, but there were highly significant differences between these levels. In heredofamilial amyloid, SAA levels were within normal limits. While the mean SAA level was elevated in persons over 70 years, the fact that some persons in this age group had normal levels suggested that marked elevation after age 70 may be due to occult inflammatory or neoplastic disease. High SAA levels in patients with rheumatoid arthritis correlated, in most cases, with physician evaluation of disease activity and Westergren ESR. SAA levels in patients with systemic lupus erythematosus were lower than those in patients with rheumatoid arthritis, and most patients with degenerative joint disease had normal levels. Very high levels of SAA were found in patients with neoplastic diseases. Patients with carcinoma of the lung and bowel had much higher levels than patients with carcinoma of the breast. Determination of SAA levels may be of value in evaluating different forms of systemic amyloidosis, assessing the activity of rheumatic disease, and screening for occult inflammatory or neoplastic disease

  3. Identification of Human Serum Proteins Which Interact With Alzheimer`s Amyloid ?A4 Protein

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    Golam Sadik

    2000-01-01

    Full Text Available Alzheimer`s amyloid ?A4 protein fused with glutathione S-transferase (GST was highly expressed using a strong prokaryotic expression system in Escherichia coli. The expressed protein had expected molecular mass on SDS-PAGE and appeared exclusively immunoreactive with antibody specific for ?A4 epitope. This recombinant protein was purified with a combination of urea solubilization and ion exchange chromatography. To identify the human serum proteins which interact with ?A4, affinity columns were prepared by immobilizing GST- ?A4 and GST respectively. Using the affinity columns and human serum, we have observed an interaction of ?A4 with serum proteins. Two proteins of Mr 45 and 15 kDa were identified on SDS-PAGE to be involved in the interaction. Our demonstration of the ability of ?A4 to interact with serum protein strongly support the notion that such an interaction may underlie with the biological function of ?A4 in vivo.

  4. Human serum amyloid A. Three hepatic mRNAs and the corresponding proteins in one person.

    Science.gov (United States)

    Kluve-Beckerman, B; Dwulet, F E; Benson, M D

    1988-01-01

    Serum amyloid A protein (SAA) is a major acute-phase protein in humans and most other mammals. In addition, it is the serum precursor of the major protein constituent of reactive amyloid fibrils. Sequence analyses have identified a number of polymorphic forms of human SAA and amyloid A protein (AA), but the question of the number of genes encoding SAA in the human has not been addressed. In addition, there are insufficient data to predict whether one form of SAA predisposes to amyloid fibril formation. In the present study three separate SAA proteins have been isolated from the plasma of one individual and completely sequenced. While two of the SAA forms (SAA2 alpha and SAA2 beta) differ from each other only at position 71, they differ from the most abundant form (SAA1) at seven and eight other positions, respectively. Nucleotide sequencing of cDNAs from a liver library of this individual identified all three mRNs coding for these proteins and proved that: (a) the often-reported absence of arginine at the amino terminus of SAA proteins must result from proteolytic processing of the protein; (b) the polymorphism involving histidine and arginine at position 71 is present at the DNA level and therefore is not due to an event at the translational level; (c) there are at least two genes coding for human SAA. Comparison of these data to published sequences of SAA and AA proteins may help in identifying genetically determined forms of SAA which predispose to reactive amyloid fibril formation. Images PMID:3183061

  5. A comparison of serum amyloid A (SAA) synthesis with that of the pentraxins: Serum amyloid P (SAP) and C-reactive protein (CRP)

    International Nuclear Information System (INIS)

    Serum amyloid A (SAA) and serum amyloid P (SAP) were detected in cultures of hepatocytes which had been isolated from normal CBA/J mice by the collagenase perfusion technique. SAP production in 24 h cultures was more resistant than SAA and total protein synthesis to inhibition by actinomycin D, but was more sensitive to inhibition by 48 h. However, the production of SAP was more sensitive to cycloheximide than SAA and total protein throughout the 48 hr incubation period. SAP and SAA levels in the culture media were suppressed by treatment of liver cells with 10-6 M of colchicine for 48 h. Inhibition of SAP production by colchicine was the same regardless of culture condition, but the effect of colchicine on SAA synthesis varied according to the presence of serum of monokine. These observations also support the concept that the two amyloid proteins are produced under different regulatory mechanisms. When C-reactive protein (CRP) was not detected in the sera of patients with severe chronic liver diseases, the SAA levels were very low. When CRP was detected, SAA values were within the normal range. Thus, in order to produce SAA, liver cells in these patients not only were viable but also maintained their specialized function

  6. Effect of colchicine on the acute phase serum amyloid A protein response and splenic amyloid deposition during experimental murine inflammation

    International Nuclear Information System (INIS)

    We investigated the effects of colchicine on the acute phase serum amyloid A protein (SAA) response and splenic amyloid A protein (AA) deposition in CBA/J mice undergoing chronic inflammatory stimulation with silver nitrate (AgNO3), and on accelerated amyloid deposition induced by amyloidenhancing factor (AEF). Colchicine (10 microg daily) significantly lowered splenic AA levels after 25 days of inflammation, as determined by radioimmunoassay. Pretreatment (3 days) with colchicine decreased SAA levels 24 h after AgNO3. It was (unexpectedly) observed that brief pretreatment (12 h) with colchicine augmented the acute phase SAA response to AgNO3 at 24 h. Colchicine stimulated production of both the SAA inducer and lymphocyte-activating factor (LAF) activities of interleukin 1 (IL 1) by macrophages. Decreased SAA levels did not appear to be the mechanism by which colchicine inhibited amyloidosis, since SAA levels fell both in colchicinetreated and control mice after 25 days of inflammation. Colchicine only partially lowered AA deposition after injection of AEF. This effect could be explained by decreased acute phase SAA levels. It is postulated that colchicine inhibits amyloidosis in the pre-deposition period by altering the production of factors (e.g., AEF) required in the deposition phase

  7. Serum amyloid A protein (SAA) from mink, horse, and man: a comparative study

    International Nuclear Information System (INIS)

    Serum amyloid A protein (SAA) was isolated from mink, horse, and human serum by ultracentrifugation and gel filtration and characterized by two-dimensional gel electrophoresis, Western blotting followed by autoradiography and N-terminal amino acid analysis. SAA was found in similar quantities in the high density lipoprotein (HDL) fraction of serum from a patient suffering from systemic juvenile rheumatoid arthritis (JRA) and mink stimulated with lipopolysaccharide (LPS), and in somewhat smaller quantities in serum from horses stimulated with Escherichia coli cultures. Only very small quantities were present in normal human controls and not detectable in normal mink and horse. Striking similarities were found between human and mink SAA with respect to molecular weight, isolectric point and degree of heterogeneity, while the molecular weight, isolectric point and degree of heterogeneity, while the molecular weight of horse SAA seemed to be somewhat lower, and no obvious heterogeneity could be demonstrated in this protein using two-dimensional gel electrophoresis. Immunologic cross-reactivity between SAA from the three species was not found. In contrast to human and horse HDL, mink HDL was found not to contain apoA-II and only minute amounts of apoC proteins. Normal horse HDL also contained additional apoproteins not present in HDL from the other species. N-terminal amino acids analysis of SAA from mink and horse demonstrated the same similarity with the corresponding AA protein as previously reported for human SAA/AA

  8. Solid-phase immunoradiometric assay for serum amyloid A protein using magnetisable cellulose particles

    International Nuclear Information System (INIS)

    An immunoradiometric assay for human serum amyloid A protein (SAA) was developed using magnetisable cellulose particles as the solid phase. Rabbit antiserum to SAA was raised by immunization with SAA isolated from acute-phase serum by gel filtration in formic acid. The antiserum was rendered monospecific for SAA by solid-phase immunoabsorption with normal human serum, which contains only traces of SAA, and some was coupled covalently to the cellulose particles. Immunopurified anti-SAA antibodies were isolated from the monospecific anti-SAA serum by binding to, and elution from insolubilized acute-phase serum and were radiolabelled with 125I. The assay was calibrated with an acute phase serum which contained 6000 times more SAA than normal sera with the lowest detectable level of SAA, and an arbitrary value of 6000 U/l was assigned to this standard. Sera were tested in the native, undenatured state and there was no increase in SAA immunoreactivity following alkali treatment or heating. The assay range was from 1-2000 U/l so that all SAA levels above 6 U/l could be measured on a single (1:6) dilution of serum. The intra- and interassay coefficients of variation were 11.7 and 15.0% respectively. Among 100 healthy normal subjects (50 male, 50 female) the median SAA level was 9 U/l, range <1-100, with 93% below 20 U/l and only 2% below the lower limit of sensitivity of the assay (1 U/l). (Auth.)

  9. Comparison of serum amyloid A and C-reactive protein as diagnostic markers of systemic inflammation in dogs

    DEFF Research Database (Denmark)

    Christensen, Michelle Brønniche; Langhorn, Rebecca; Goddard, Amelia; Andreasen, Eva Bartholin; Moldal, Elena; Tvarijonaviciute, Asta; Kirpensteijn, Jolle; Jakobsen, Sabrina; Persson, Frida; Kjelgaard-Hansen, Mads

    2014-01-01

    The diagnostic performance of canine serum amyloid A (SAA) was compared with that of C-reactive protein (CRP) in the detection of systemic inflammation in dogs. Sera from 500 dogs were retrospectively included in the study. C-reactive protein and SAA were measured using validated automated assays. The overlap performance, clinical decision limits, overall diagnostic performance, correlations, and agreement in the clinical classification between these 2 diagnostic markers were compared. Significa...

  10. Evaluation of Sialic Acid and Acute Phase Proteins (Haptoglobin and Serum Amyloid A) in Clinical and Subclinical Bovine Mastitis

    OpenAIRE

    S. Nazifi*, M. Haghkhah1, Z. Asadi, M. Ansari-Lari2, M. R. Tabandeh3, Z. Esmailnezhad and M. Aghamiri

    2011-01-01

    The present study was conducted to evaluate the concentrations of sialic acids (total, lipid bound and protein bound) and their correlation with acute phase proteins (haptoglobin and serum amyloid A) in clinical and subclinical mastitis of cattle. Thirty subclinical mastitic cows with positive California mastitis test (CMT) test and no clinical signs of mastitis, 10 clinical mastitic cows and 10 healthy cows with negative CMT test and normal somatic cell count were selected. Milk and blood sa...

  11. Native human serum amyloid P component is a single pentamer

    DEFF Research Database (Denmark)

    Sørensen, Inge Juul; Andersen, Ove; Nielsen, EH; Svehag, SE

    1995-01-01

    Serum amyloid P component (SAP) and C-reactive protein (CRP) are members of the pentraxin protein family. SAP is the precursor protein to amyloid P component present in all forms of amyloidosis. The prevailing notion is that SAP in circulation has the form of a double pentameric molecule (decamer) whereas CRP is a single pentameric molecule. We have investigated by gel permeation chromatography the M(r) of SAP in freshly collected human serum and of SAP purified by carbohydrate affinity chromato...

  12. Comparison of serum amyloid A and C-reactive protein as diagnostic markers of systemic inflammation in dogs

    DEFF Research Database (Denmark)

    Christensen, Michelle BrØnniche; Langhorn, Rebecca

    2014-01-01

    The diagnostic performance of canine serum amyloid A (SAA) was compared with that of C-reactive protein (CRP) in the detection of systemic inflammation in dogs. Sera from 500 dogs were retrospectively included in the study. C-reactive protein and SAA were measured using validated automated assays. The overlap performance, clinical decision limits, overall diagnostic performance, correlations, and agreement in the clinical classification between these 2 diagnostic markers were compared. Significantly higher concentrations of both proteins were detected in dogs with systemic inflammation (SAA range: 48.75 to > 2700 mg/L; CRP range: 0.4 to 907.4 mg/L) compared to dogs without systemic inflammation (SAA range: 1.06 to 56.4 mg/L; CRP range: 0.07 to 24.7 mg/L). Both proteins were shown to be sensitive and specific markers of systemic inflammation in dogs. Significant correlations and excellent diagnostic agreement were observed between the 2 markers. However, SAA showed a wider range of concentrations and a significantly superior overall diagnostic performance compared with CRP.

  13. Human serum amyloid genes--molecular characterization

    International Nuclear Information System (INIS)

    Three clones containing human genes for serum amyloid A protein (SAA) have been isolated and characterized. Each of two clones, GSAA 1 and 2 (of 12.8 and 15.9 kilobases, respectively), contains two exons, accouting for amino acids 12-58 and 58-103 of mature SAA; the extreme 5' termini and 5' untranslated regions have not yet been defined but are anticipated to be close based on studies of murine SAA genes. Initial amino acid sequence comparisons show 78/89 identical residues. At 4 of the 11 discrepant residues, the amino acid specified by the codon is the same as the corresponding residue in murine SAA. Identification of regions containing coding regions has permitted use of selected subclones for blot hybridization studies of larger human SAA chromosomal gene organization. The third clone, GSAA 3 also contains SAA coding information by DNA sequence analysis but has a different organization which has not yet been fully described. We have reported the isolation of clones of human DNA hybridizing with pRS48 - a plasmid containing a complementary DNA (cDNA) clone for murine serum amyloid A (SAA; 1, 2). We now present more detailed data confirming the identity and defining some of the organizational features of these clones

  14. Protein Polymers and Amyloids

    DEFF Research Database (Denmark)

    Risør, Michael Wulff

    2014-01-01

    Several human disorders are caused by a common general disease mechanism arising from abnormal folding and aggregation of the underlying protein. These include the prevalent dementias like Alzheimer’s and Parkinson’s, where accumulation of protein fibrillar structures, known as amyloid fibrils, is a general hallmark. They also include the ?1-antitrypsin deficiency, where disease-causing mutations in the serine protease inhibitor, ?1-antitrypsin (?1AT), leads to accumulation of the aberrant prote...

  15. Serum amyloid A: A new potential serum marker correlated with the stage of breast cancer

    OpenAIRE

    Zhang, Guojun; Sun, Xudong; LV, HONG; Yang, Xiaolin; KANG, XIXIONG

    2012-01-01

    Previous studies reported that serum amyloid A (SAA) is elevated in patients with tumors, including breast cancer, compared to healthy controls. In addition, the levels of SAA increase gradually with tumor progression. In this study, we investigated the blood SAA level of breast cancer patients, and evaluated its potential as a serum biomarker for the early diagnosis of breast cancer and as a staging estimate. SAA protein was determined by enzyme-linked immunosorbent assay in serum samples fr...

  16. Kinetics of human serum amyloid A

    International Nuclear Information System (INIS)

    In order to better understand the pathogenetic role of serum amyloid A (SAA) we studied the kinetics of 131I radiolabelled pure SAA, extracted from 400 ml serum of a human volunteer. 50 microCi of 131I SAA and 15 microCi 125I labelled sodium iodide were administered i.v. on two occasions at 6 month intervals. Serum and plasma samples were collected at 10-20 min intervals x 10, then once daily x 10; lymphocytes were separated from monocytes and granulocytes. Counts per minute of 131I and 125I were measured in each sample in the serum, in serum precipitates resulting after addition of a rabbit anti-SAA antibody and of TCA and in various cell subpopulations as well as in the whole urine and TCA precipitated urine from each micturition. The 131I disappearance curves from the plasma and serum precipitates were semilogarithmically plotted; cumulative 131I cpm in plasma, cells and urine at various intervals were determined. Body scanning was performed at 2, 16, and 48 h. The results of the two experiments were very similar. The curve of 131I SAA in plasma TCA precipitates indicated the existence of 4 compartments likely due to uptake of 131I SAA by some plasma proteins, circulating cells and other tissues; later release from tissues started at 6 h. The 131I SAA half-life time in these compartments was found to be 35, 170, 255, and 550 min, respectively. Tissue binding of 131I was also suggested by a rising of the 125I:131I ratio with time and by a 26% release of 131I in the urine at 15 h which could not account for its plasma disappearance. Scanning, except for 131I uptake in the spleen at 2 h likely due to blood activity, showed no organ concentration. 92% of the injected 131I was found in the urine but only 6.2% of 131I SAA was accounted for in urine precicipitates

  17. Effects of Chinese herbal medicine Guanxinkang on lipid metabolism and serum C-reactive protein, amyloid A protein, and fibrinogen in apolipoprotein E-knockout mice with atherosclerosis

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    Mei-jiao Mao

    2011-03-01

    Full Text Available Objective: To observe the effects of Guanxinkang (GXK decoction, a compound traditional Chinese herbal medicine, on serum lipids and apolipoprotein A ? (ApoA ?, apolipoprotein B (ApoB, apolipoprotein E (ApoE, C-reactive protein (CRP, serum amyloid A protein (SAA and fibrinogen (Fbg concentrations of ApoE-knockout mice with atherosclerosis, and to explore the mechanism of GXK decoction in anti-atherosclerosis.Methods: Seventy 6-week-old ApoE-knockout mice receiving a high-cholesterol diet were used to induce atherosclerosis and were randomly divided into 5 groups: untreated group, simvastatin group and low- (drug concentration is 0.864 g/mL, medium- (1.728 g/mL, and high-dose (3.456 g/mL GXK groups. Another fourteen 6-week-old C57BL/6J mice were used as the normal control. Two 12-week-old mice were randomly selected from the normal control and the ApoE-knockout mice respectively to observe vulnerable plaque in the mouse’s aortic by hematoxylin-eosin staining. Blood was collected from venous plexus of eye socket after gavage of corresponding drugs once daily for 8 weeks continuously, and then the serum was separated. Triglyceride (TAG and total cholesterol (TC were measured by enzyme-coupled assay; low-density lipoprotein cholesterol (LDL-C and high-density lipoprotein cholesterol (HDL-C were measured by selective precipitation method. Serum levels of ApoA ? and ApoB were determined by turbidimetry. Double-antibody sandwich enzyme-linked immunosorbent assay was used to detect ApoE, CRP, SAA and Fbg concentrations in serum.Results: Compared with the normal control group, the levels of serum TC, TAG, LDL-C, ApoB, CRP, SAA and Fbg in the untreated group were increased (P<0.05, and the serum concentrations of HDL-C, ApoA ? and ApoE in the untreated group were decreased (P<0.05. After treatment, GXK decoction and simvastatin improved the dyslipidemia by increasing the concentrations of ApoA ? and HDL-C and decreasing the concentrations of TC, TAG, LDL-C, ApoB, CRP, SAA and Fbg (P<0.05. The high-dose GXK decoction had the most marked effects on SAA and Fbg and the serum lipids compared with the low-dose and medium-dose GXK and simvastatin.Conclusion: GXK decoction may not only provide an active effect on hyperlipidemia, but also down-regulate the levels of serum CRP, SAA and Fbg. GXK decoction exerts an anti-atherosclerosis effect in ApoE-knockout mice.

  18. Serum amyloid P inhibits dermal wound healing

    OpenAIRE

    Naik-Mathuria, Bindi; Pilling, Darrell; Crawford, Jeff R.; Gay, Andre N.; Smith, C Wayne; Gomer, Richard H.; Olutoye, Oluyinka O

    2008-01-01

    The repair of open wounds depends on granulation tissue formation and contraction, which is primarily mediated by myofibroblasts. A subset of myofibroblasts originates from bone-marrow-derived monocytes which differentiate into fibroblast-like cells called fibrocytes. Serum amyloid P (SAP) inhibits differentiation of monocytes into fibrocytes. Thus, we hypothesized that the addition of exogenous SAP would hinder the normal wound healing process. Excisional murine dorsal wounds were either inj...

  19. Binding of complement proteins C1q and C4bp to serum amyloid P component (SAP) in solid contra liquid phase.

    DEFF Research Database (Denmark)

    SØrensen, Inge Juul; Nielsen, EH

    1996-01-01

    Serum amyloid P component (SAP), a member of the conserved pentraxin family of plasma proteins, binds calcium dependently to its ligands. The authors investigated SAPs interaction with the complement proteins C4b binding protein (C4bp) and C1q by ELISA, immunoelectrophoresis and electron microscopy. Binding of these proteins to SAP was demonstrated when SAP was immobilized using F(ab')2 anti-SAP, but not when SAP reacted with these proteins in liquid phase; thus the binding to human SAP was markedly phase state dependent. Presaturation of solid phase SAP with heparin, which binds SAP with high affinity, did not interfere with the subsequent binding of C4bp or C1q to SAP. In contrast, collagen I and IV showed partial competition with the binding of C1q to SAP. Using fresh serum, immobilized native SAP bound C4bp whereas binding of C1q/C1 could not be demonstrated. Altogether the results indicate that firm binding of C1q and C4bp to SAP requires that SAP is presented on a solid phase, that C1q and C4bp react with sites distinct from the heparin binding site, and that C1q and collagen I share binding sites on SAP. Immobilized native SAP, aggregated SAP and SAP-heparansulphate complexes induced no detectable complement activation.

  20. Serum amyloid A in the mouse. Sites of uptake and mRNA expression.

    OpenAIRE

    Meek, R L; Eriksen, N; Benditt, E P

    1989-01-01

    Murine serum amyloid A1 (SAA1) and serum amyloid A2 (SAA2) are circulating, acute phase, high density apolipoproteins of unknown function. To pursue issues relating to their possible function their uptake and formation were studied. Kinetics of SAA protein distribution and gene expression after acute phase stimulation by casein or lipopolysaccharide were examined using immunocytochemistry for protein and RNA blot and in situ hybridization with probes for SAA1 and SAA2 mRNA. After casein injec...

  1. Serum amyloid P component scintigraphy in familial amyloid polyneuropathy: regression of visceral amyloid following liver transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Rydh, A.; Hietala, S.O.; Aahlstroem, K.R. [Department of Diagnostic Radiology, University Hospital of Northern Sweden, Umeaa (Sweden); Suhr, O. [Department of Internal Medicine, University Hospital of Northern Sweden, Umeaa (Sweden); Pepys, M.B.; Hawkins, P.N. [Immunological Medicine Unit, Department of Medicine, Imperial College School of Medicine, London (United Kingdom)

    1998-07-01

    Familial amyloid polyneuropathy (FAP) associated with transthyretin (TTR) mutations is the commonest type of hereditary amyloidosis. Plasma TTR is produced almost exclusively in the liver and orthotopic liver transplantation is the only available treatment, although the clinical outcome varies. Serum amyloid P component (SAP) scintigraphy is a method for identifying and quantitatively monitoring amyloid deposits in vivo, but it has not previously been used to study the outcome of visceral amyloid deposits in FAP following liver transplantation. Whole body scintigraphy following injection of iodine-123 labelled SAP was performed in 17 patients with FAP associated with TTR Met30 and in five asymptomatic gene carriers. Follow-up studies were performed in ten patients, eight of whom had undergone orthotopic liver transplantation 1-5 years beforehand. There was abnormal uptake of {sup 123}I-SAP in all FAP patients, including the kidneys in each case, the spleen in five cases and the adrenal glands in three cases. Renal amyloid deposits were also present in three of the asymptomatic carriers. Follow-up studies 1-5 years after liver transplantation showed that there had been substantial regression of the visceral amyloid deposits in two patients and modest improvement in three cases. The amyloid deposits were unchanged in two patients. In conclusion, {sup 123}I-SAP scintigraphy identified unsuspected visceral amyloid in each patient with FAP due to TTR Met30. The universal presence of renal amyloid probably underlies the high frequency of renal failure that occurs in FAP following liver transplantation. The variable capacity of patients to mobilise amyloid deposits following liver transplantation may contribute to their long-term clinical outcome. (orig.) With 2 figs., 2 tabs., 22 refs.

  2. Serum amyloid P component scintigraphy in familial amyloid polyneuropathy: regression of visceral amyloid following liver transplantation

    International Nuclear Information System (INIS)

    Familial amyloid polyneuropathy (FAP) associated with transthyretin (TTR) mutations is the commonest type of hereditary amyloidosis. Plasma TTR is produced almost exclusively in the liver and orthotopic liver transplantation is the only available treatment, although the clinical outcome varies. Serum amyloid P component (SAP) scintigraphy is a method for identifying and quantitatively monitoring amyloid deposits in vivo, but it has not previously been used to study the outcome of visceral amyloid deposits in FAP following liver transplantation. Whole body scintigraphy following injection of iodine-123 labelled SAP was performed in 17 patients with FAP associated with TTR Met30 and in five asymptomatic gene carriers. Follow-up studies were performed in ten patients, eight of whom had undergone orthotopic liver transplantation 1-5 years beforehand. There was abnormal uptake of 123I-SAP in all FAP patients, including the kidneys in each case, the spleen in five cases and the adrenal glands in three cases. Renal amyloid deposits were also present in three of the asymptomatic carriers. Follow-up studies 1-5 years after liver transplantation showed that there had been substantial regression of the visceral amyloid deposits in two patients and modest improvement in three cases. The amyloid deposits were unchanged in two patients. In conclusion, 123I-SAP scintigraphy identified unsuspected visceral amyloid in each patient with FAP due to TTR Met30. The universal presence of renal amyloid probably underlies the high frequency of renal failure that occurs in FAP following liver transplantation. The variable capacity of patients to mobilise amyloid deposits following liver transplantation may contribute to their long-term clinical outcome. (orig.)

  3. Proteomic screening for amyloid proteins.

    Science.gov (United States)

    Nizhnikov, Anton A; Alexandrov, Alexander I; Ryzhova, Tatyana A; Mitkevich, Olga V; Dergalev, Alexander A; Ter-Avanesyan, Michael D; Galkin, Alexey P

    2014-01-01

    Despite extensive study, progress in elucidation of biological functions of amyloids and their role in pathology is largely restrained due to the lack of universal and reliable biochemical methods for their discovery. All biochemical methods developed so far allowed only identification of glutamine/asparagine-rich amyloid-forming proteins or proteins comprising amyloids that form large deposits. In this article we present a proteomic approach which may enable identification of a broad range of amyloid-forming proteins independently of specific features of their sequences or levels of expression. This approach is based on the isolation of protein fractions enriched with amyloid aggregates via sedimentation by ultracentrifugation in the presence of strong ionic detergents, such as sarkosyl or SDS. Sedimented proteins are then separated either by 2D difference gel electrophoresis or by SDS-PAGE, if they are insoluble in the buffer used for 2D difference gel electrophoresis, after which they are identified by mass-spectrometry. We validated this approach by detection of known yeast prions and mammalian proteins with established capacity for amyloid formation and also revealed yeast proteins forming detergent-insoluble aggregates in the presence of human huntingtin with expanded polyglutamine domain. Notably, with one exception, all these proteins contained glutamine/asparagine-rich stretches suggesting that their aggregates arose due to polymerization cross-seeding by human huntingtin. Importantly, though the approach was developed in a yeast model, it can easily be applied to any organism thus representing an efficient and universal tool for screening for amyloid proteins. PMID:25549323

  4. Ligand-binding sites in human serum amyloid P component

    DEFF Research Database (Denmark)

    Heegaard, N.H.H.; Heegaard, Peter M. H.; Roepstorff, P.; Robey, F.A.

    1996-01-01

    Amyloid P component (AP) is a naturally occurring glycoprotein that is found in serum and basement membranes, AP is also a component of all types of amyloid, including that found in individuals who suffer from Alzheimer's disease and Down's syndrome. Because AP has been found to bind strongly and specifically to certain glycosaminoglycans that are components of amyloid deposits, AP may play an important role in the maintenance of amyloid. In the present work, we isolated and identified two prote...

  5. Specific localization and imaging of amyloid deposits in vivo using /sup 123/I-labeled serum amyloid P component

    Energy Technology Data Exchange (ETDEWEB)

    Hawkins, P.N.; Myers, M.J.; Epenetos, A.A.; Caspi, D.; Pepys, M.B.

    1988-03-01

    Highly specific, high-resolution scintigraphic images of amyloid-laden organs in mice with experimentally induced amyloid A protein (AA) amyloidosis were obtained after intravenous injection of /sup 123/I-labeled serum amyloid P component (SAP). Interestingly, a much higher proportion (up to 40%) of the injected dose of heterologous human SAP localized to amyloid and was retained there than was the case with isologous mouse SAP, indicating that human SAP binds more avidly to mouse AA fibrils than does mouse SAP. Specificity of SAP localization was established by the failure of the related proteins, human C-reactive protein and Limulus C-reactive protein, to deposit significantly in amyloid and by the absence of human SAP deposition in nonamyloidotic organs. However, only partial correlations were observed between the quantity of SAP localized and two independent estimates, histology and RIA for AA of the amount of amyloid in particular organs. It is not clear which of the three methods used reflects better the extent or clinical significance of the amyloid deposits but in vivo localization of radiolabeled SAP, detectable and quantifiable by gamma camera imaging, is apparently extremely sensitive. These findings establish the use of labeled SAP as a noninvasive in vivo diagnostic probe in experimental amyloidosis, potentially capable of revealing the natural history of the condition, and suggest that it may also be applicable generally as a specific targeting agent for diagnostic and even therapeutic purposes in clinical amyloidosis.

  6. An in vitro study on neuroprotective effects of serum containing Gengnianchun decoction and its main monomers against amyloid beta protein-induced cellular toxicity

    Directory of Open Access Journals (Sweden)

    Wen-jun WANG

    2010-01-01

    Full Text Available Obiective: To observe the effects of serum containing Gengnianchun (GNC decoction, a compound traditional Chinese herbal medicine, and its monomers (paeoniflorin, berberine, timosaponin A-? and icariin on neurotoxicity in PC12 cells induced by amyloid beta-protein (A?.?Methods: Injury of PC12 cells was induced by in incubating with A?25-35 in vitro.? Ovariectomized rats were intragastrically administered with GNC decoction twice daily for 5 days and then sera were obtained. Different concentrations of serum containing GNC decoction and its main monomers including paeoniflorin, berberine, timosaponin and icariine and the monomer mixtures were cultured with PC12 cells to determine the best concentration of the drugs by methyl thiazolyl tetrazolium (MTT method. The effective concentration of A?25-35 was detemined by culturing PC12 cells with different concentrations of A?25-35. Then, the activity of PC12 cells with A?25-35-induced injury was observed with MTT method. Cellular morphological change was observed by phase contrast microscopy. Flow cytometry and fluorescence microscopy were employed to observe the A?25-35-induced early apoptosis of PC12 cells.?Results: After A?25-35 induction, the PC12 cells were fewer in number, less viable with shrinked cel1 body, many fragments, adhered less and nuclei shrinked. The cell proliferation was inhibited by A?25-35 concentration- and time?dependently. A?25-35 at concentration of 20 ?mol/ L was selected to construct the Alzheimer's disease model ?in vitro.? The sera containing GNC decoction could reinforce PC12 cell activity, and concentration at 20% was better than other concentrations after 24-, 48- and 72-hour culture. The 20% serum containing GNC decoction, 0.1 ?mol/L berberin and monomer mixture 3 including 1 mg/mL paeoniflorin, 1 ?mol/L berberine, 1 ?mol/L timosaponin and 1 ng/mL icariine could antagonize neurotoxicity induced by A?25-35. Moreover, they could inhibit A?25-35-induced early apoptosis of PC12 cells, with the effect of 20% serum containing GNC decoction better than 0.1 ?mol/L berberine and monomer mixture 3.Conclusion: Serum containing GNC decoction at 20% concentration has the potential neuroprotective effect on A?-induced cellular impairment. The serum containing GNC decoction was found to be stronger in action than the main monomers.

  7. Amyloid ? protein and Alzheimer disease

    OpenAIRE

    Square, D.

    1997-01-01

    Amyloid beta protein is predominant in senile plaques, the neuropathologic hallmarks of Alzheimer disease. Researchers in Winnipeg have shown that this protein can overstimulate certain hydrolytic enzymes to break down the phospholipid building blocks of the brain-cell wall. They speculate that the abnormal destruction of phospholipids gradually drains the energy resources a neuron uses to rebuild its membrane. As neurons "burn out," the brain loses its ability to function normally. In view o...

  8. Systemic reactive amyloidosis associated with Castleman's disease: serial changes of the concentrations of acute phase serum amyloid A and interleukin 6 in serum.

    OpenAIRE

    Ikeda, S; Chisuwa, H; Kawasaki, S.; Ozawa, J; Hoshii, Y; Yokota, T; Aoi, T

    1997-01-01

    A case is reported of a 21 year old woman who suffered from Castleman's disease and systemic reactive amyloidosis. The serum concentrations of serum amyloid A (SAA) and interleukin 6 (IL-6) were extremely high and amyloid protein was immunohistochemically identified as AA. After surgical excision of a large retroperitoneal lymph node with the pathological findings of plasma cell type of Castleman's disease, both serum SAA and IL-6 declined, showing a similar pattern of reduction curves. All c...

  9. C-reactive protein and serum amyloid A as early-phase and prognostic indicators of acute radiation exposure in nonhuman primate total-body irradiation model

    International Nuclear Information System (INIS)

    Terrorist radiological attacks or nuclear accidents could expose large numbers of people to ionizing radiation. In mass-casualty radiological incidents early medical-management requires triage tools for first-responders to quantitatively identify individuals exposed to life-threatening radiation doses and for early initiation (i.e., within one day after radiation exposure) of cytokine therapy for treatment of bone marrow acute radiation syndrome. Herein, we present results from 30 rhesus macaques total-body irradiated (TBI) to a broad dose range of 1-8.5 Gy with 60Co ?-rays (0.55 Gy min-1) and demonstrate dose- and time-dependent changes in blood of C-reactive protein (CRP), serum amyloid A (SAA), and interleukin 6 (IL-6) measured by enzyme linked immunosorbent assay (ELISA). CRP and SAA dose-response results are consistent with ?1 Gy and ?0.2 Gy thresholds for photon-exposure at 24 h after TBI, respectively. Highly significant elevations of CRP and SAA (p = 0.00017 and p = 0.0024, respectively) were found in animal plasma at 6 h after all TBI doses suggesting their potential use as early-phase biodosimeters. Results also show that the dynamics and content of CRP and SAA levels reflect the course and severity of the acute radiation sickness (ARS) and may function as prognostic indicators of ARS outcome. These results demonstrate proof-of-concept that these radiation-responsive proteins show promise as a complementary approach to conventional biodosimetry for early assessment of radiation exposures and may also contribute as diagnostic indices in the medical management of radiation accidents.

  10. Molecular characterization of two immunity-related acute-phase proteins: Haptoglobin and serum amyloid A from black rockfish (Sebastes schlegeli).

    Science.gov (United States)

    Jayasinghe, J D H E; Elvitigala, Don Anushka Sandaruwan; Whang, Ilson; Nam, Bo-Hye; Lee, Jehee

    2015-08-01

    Haptoglobin (Hp) and serum amyloid A (SAA) are two vital proteins involved in inflammatory reactions and are classified as acute-phase proteins. They are released from hepatocytes under inflammatory conditions to protect healthy cells from being damaged by pathogens or from self-destructive mechanisms. In this study, a previously constructed black rockfish (Sebastes schlegeli) cDNA library was used to identify the full-length cDNA sequences of Hp and SAA homologs (RfHp and RfSAA, respectively) and characterize them at the molecular level. As expected, in silico analysis of these homologs showed the typical domain architectures of their known counterparts. Open reading frames of RfHp and RfSAA consisted of 942-bp and 313-bp DNA sequences, respectively. The derived polypeptide sequence of RfHp was composed of 313 amino acids (aa) with a predicted molecular weight of 34 kD, whereas RfSAA had a 121-amino acid sequence with a molecular weight of 13 kD. Phylogenetic analysis as well as pairwise sequence alignment results showed that RfHp was more closely related to Oreochromis mossambicus from an evolutionary perspective while RfSAA was closely related to the Epinephelus coioides ortholog. Although both genes were expressed ubiquitously in the tissues analyzed, they were particularly expressed in liver tissue, suggesting their origin in hepatocytes. Quantitative real-time PCR analysis indicated that both RfHp and RfSAA were significantly up-regulated by both bacterial and viral stimulation in liver tissue, affirming their putative importance in the acute phase of first-line host immune defenses. PMID:25989623

  11. Purification, subunit characterization and ultrastructure of three soluble bovine lectins: conglutinin, mannose-binding protein and the pentraxin serum amyloid P-component.

    DEFF Research Database (Denmark)

    Andersen, Ove; Friis, P

    1992-01-01

    Conglutinin and mannose-binding protein (MBP) are members of the C-type lectins which are widely present in mammalian plasma. Serum amyloid P-component (SAP) is a member of the pentraxin family with lectin properties. A scheme for the partial purification of all three lectins by carbohydrate affinity chromatography and selective elution was developed. The purification was monitored by SDS-PAGE, Western blotting and electron microscopy. Binding of the lectins to Sephadex-iC3b, their collagenase sensitivity, and the size and antibody reactivity of their subunits was investigated. The demonstration, by SDS-PAGE, of 25-kDa subunits, which were unaffected by collagenase treatment but bound to Sephadex-iC3b and antibodies to human SAP, indicated the existence of bovine SAP. Bovine conglutinin (BK) also showed calcium-dependent binding to Sephadex-iC3b, whereas bovine MBP did not. The binding of BK was inhibitable with GlcNAc. A 3000-fold increase in BK activity (ELISA) was obtained in eluates from Sephadex-iC3b. SDS-PAGE analyses of BK and MBP revealed subunits with an Mr of 43 kDa and 30 kDa, respectively. These subunits were sensitive to collagenase treatment which reduced the Mr to 20 kDa. Electron micrographs revealed a prominent flexible tetramer molecule (diameter 96 nm) in the BK preparations, a predominantly hexameric structure (diameter 30 nm) in the MBP preparations, and single annular pentameric disc-like molecules (diameter 11 nm) in the SAP preparations.

  12. Transthyretin Sequesters Amyloid ? Protein and Prevents Amyloid Formation

    Science.gov (United States)

    Schwarzman, Alexander L.; Gregori, Luisa; Vitek, Michael P.; Lyubski, Sergey; Strittmatter, Warren J.; Enghilde, Jan J.; Bhasin, Ramaninder; Silverman, Josh; Weisgraber, Karl H.; Coyle, Patricia K.; Zagorski, Michael G.; Talafous, Joseph; Eisenberg, Moises; Saunders, Ann M.; Roses, Allen D.; Goldgaber, Dmitry

    1994-08-01

    The cardinal pathological features of Alzheimer disease are depositions of aggregated amyloid ? protein (A?) in the brain and cerebrovasculature. However, the A? is found in a soluble form in cerebrospinal fluid in healthy individuals and patients with Alzheimer disease. We postulate that sequestration of A? precludes amyloid formation. Failure to sequester A? in Alzheimer disease may result in amyloidosis. When we added A? to cerebrospinal fluid of patients and controls it was rapidly sequestered into stable complexes with transthyretin. Complexes with apolipoprotein E, which has been shown to bind A? in vitro, were not observed in cerebrospinal fluid. Additional in vitro studies showed that both purified transthyretin and apolipoprotein E prevent amyloid formation.

  13. Serum amyloid A isoforms in serum and synovial fluid from spontaneously diseased dogs with joint diseases or other conditions

    DEFF Research Database (Denmark)

    Kjelgaard-Hansen, Mads Jens; Christensen, Michelle B.; Lee, Marcel Huisung; Jensen, Asger Lundorff; Jacobsen, Stine

    2007-01-01

    Serum amyloid A (SAA) is a major acute phase protein in dogs. However, knowledge of qualitative properties of canine SAA and extent of its synthesis in extrahepatic tissues is limited. The aim of the study was to investigate expression of different SAA isoforms in serum and synovial fluid in samples obtained from dogs (n = 16) suffering from different inflammatory or non-inflammatory conditions, which were either related or unrelated to joints. Expression of SAA isoforms was visualized by denatu...

  14. Protein electrophoresis - serum

    Science.gov (United States)

    This lab test measures the types of protein in the fluid (serum) part of a blood sample. Other electrophoresis tests that measure proteins in the serum include: Immunoelectrophoresis Immunofixation Globulin electrophoresis

  15. Transthyretin sequesters amyloid beta protein and prevents amyloid formation

    DEFF Research Database (Denmark)

    Schwarzman, A L; Gregori, L; Vitek, M P; Lyubski, S; Strittmatter, W J; Enghild, Jan J; Bhasin, R; Silverman, J; Weisgraber, K H; Coyle, P K

    1994-01-01

    The cardinal pathological features of Alzheimer disease are depositions of aggregated amyloid beta protein (A beta) in the brain and cerebrovasculature. However, the A beta is found in a soluble form in cerebrospinal fluid in healthy individuals and patients with Alzheimer disease. We postulate that sequestration of A beta precludes amyloid formation. Failure to sequester A beta in Alzheimer disease may result in amyloidosis. When we added A beta to cerebrospinal fluid of patients and controls i...

  16. Transthyretin sequesters amyloid beta protein and prevents amyloid formation.

    OpenAIRE

    Schwarzman, A L; Gregori, L; Vitek, M.P.; Lyubski, S; Strittmatter, W. J.; Enghilde, J J; Bhasin, R; Silverman, J.; Weisgraber, K. H.; Coyle, P.K.

    1994-01-01

    The cardinal pathological features of Alzheimer disease are depositions of aggregated amyloid beta protein (A beta) in the brain and cerebrovasculature. However, the A beta is found in a soluble form in cerebrospinal fluid in healthy individuals and patients with Alzheimer disease. We postulate that sequestration of A beta precludes amyloid formation. Failure to sequester A beta in Alzheimer disease may result in amyloidosis. When we added A beta to cerebrospinal fluid of patients and control...

  17. Avaliação da proteína amilóide A sérica na atividade clínica da artrite reumatóide / Evaluation of the serum amyloid A protein in the rheumatoid arthritis clinical activity

    Scientific Electronic Library Online (English)

    Carlos Roberto Machado, Gayer; Geraldo da Rocha Castelar, Pinheiro; Carlos Augusto Ferreira de, Andrade; Sérgio Miranda, Freire; Marsen Garcia Pinto, Coelho.

    2003-08-01

    Full Text Available A artrite reumatóide (AR) é uma doença auto-imune, crônica, caracterizada pelo comprometimento inflamatório das articulações sinoviais periféricas. A proteína amilóide A sérica (SAA) é uma das principais proteínas de fase aguda (PFA), porém seu uso na rotina do laboratório clínico ainda é pouco difu [...] ndido. OBJETIVO: O objetivo deste trabalho foi analisar a utilidade da SAA na avaliação da atividade clínica da AR. MÉTODOS: Foram estudados 113 pacientes com AR, diagnosticados segundo os critérios do Colégio Americano de Reumatologia. Para a caracterização da atividade de doença, foi utilizado o Índice de Atividade de Doença (IAD), proposto pela Liga Européia Contra o Reumatismo. RESULTADOS: A SAA apresentou correlação positiva, estatisticamente significativa, com a proteína C-Reativa (PCR), tanto como a ?-1-glicoproteína ácida (AGP), quanto com o IAD. Nossos resultados demonstraram que a SAA apresentou, particularmente, uma maior sensibilidade na determinação da atividade inflamatória da AR, em comparação às outras PFA. Apresentou, também, uma boa capacidade de discriminar os grupos de atividade moderada e alta do IAD. Como o IAD não mede unicamente o componente inflamatório da AR, a dosagem de uma PFA é de grande utilidade para a caracterização da atividade dessa enfermidade. CONCLUSÕES: Os resultados deste estudo sugerem que a SAA pode ser de grande valor na determinação da atividade inflamatória da AR. Abstract in english Rheumatoid arthritis (RA) is a systemic autoimmune disease, with chronic inflammation of synovial peripheral joints as the most prominent feature. The serum amyloid A (SAA) is one of the major acute phase proteins (APP), however its use in the clinical laboratory routine is uncommon. OBJECTIVE: The [...] aim of this work was to analyze the usefulness of SAA in the evaluation of RA clinical activity. METHODS: We studied 113 patients diagnosed with RA according to the criteria of the American College of Rheumatology. The disease activity was evaluated by the Disease Activity Score (DAS) according to the European League Against Rheumatism. RESULTS: SAA presented positive correlation, statistically significant, with C-reactive protein (CRP), as well as ?-1-acid glycoprotein (AGP) and DAS. The results demonstrated that SAA presented a higher sensibility in relation to other APP in the determination of the inflammatory activity on RA patients. SAA also shows a good capability to discriminate the groups of moderate and high activity of DAS. As DAS doesn't measure only the inflammatory behavior of RA, the determination of APP is of great usefulness for the activity characterization of this illness. CONCLUSIONS: Our data suggest that SAA can be of great value in the determination of the RA inflammatory activity.

  18. A serum amyloid P-binding hydrogel speeds healing of partial thickness wounds in pigs

    OpenAIRE

    Gomer, Richard H.; Pilling, Darrell; Lawrence M. Kauvar; Ellsworth, Stote; Ronkainen, Sanna D.; Roife, David; Davis, Stephen C

    2009-01-01

    During wound healing, some circulating monocytes enter the wound, differentiate into fibroblast-like cells called fibrocytes, and appear to then further differentiate into myofibroblasts, cells that play a key role in collagen deposition, cytokine release, and wound contraction. The differentiation of monocytes into fibrocytes is inhibited by the serum protein serum amyloid P (SAP). Depleting SAP at a wound site thus might speed wound healing. SAP binds to some types of agarose in the presenc...

  19. Serum ?-1 acid glycoprotein and serum amyloid A concentrations in cats receiving antineoplastic treatment for lymphoma.

    Science.gov (United States)

    Winkel, Valter M; Pavan, Tatiana L R; Wirthl, Vera A B F; Alves, Ana L N; Lucas, Silvia R R

    2015-11-01

    OBJECTIVE To characterize serum ?-1 acid glycoprotein (AGP) and serum amyloid A (SAA) concentrations at diagnosis and during treatment in cats with lymphoma. ANIMALS 16 cats with various anatomic forms of lymphoma and 25 healthy cats. PROCEDURES Blood samples were collected from healthy cats once and from cats with lymphoma at diagnosis and 2-week intervals until the 12th week of antineoplastic treatment. Serum harvested from blood samples was assessed for AGP and SAA concentrations. Differences in serum AGP and SAA values were investigated between healthy cats and cats with lymphoma (at diagnosis) and, for cats with lymphoma, between diagnosis and various points during treatment. RESULTS Serum AGP and SAA concentrations were higher in cats with lymphoma at diagnosis (median, 832.60 and 1.03 ?g/mL, respectively), compared with those in healthy cats (median, 269.85 and 0.10 ?g/mL). Treatment resulted in a gradual decrease in serum AGP concentration after 4 weeks and in SAA concentration after 8 weeks of treatment, and these concentrations returned to values comparable with those of healthy cats by 12 weeks of treatment, by which point all cats had achieved complete remission of the disease. CONCLUSIONS AND CLINICAL RELEVANCE Serum AGP and SAA concentrations in cats with lymphoma were higher at diagnosis than after antineoplastic treatment. Decreases to values established for healthy cats corresponded with achievement of complete disease remission. Serum AGP and SAA may be useful protein markers for monitoring of antineoplastic treatment in cats with lymphoma. PMID:26512544

  20. Determination of serum amyloid P component in seminal plasma and correlations with serum hormone levels in young, healthy men.

    OpenAIRE

    Sonesson, Annika; Hillarp, Andreas; Giwercman, Aleksander; Malm, Johan

    2011-01-01

    Abstract Serum amyloid P component (SAP) belongs to the pentraxin family of proteins. SAP is evolutionary conserved, and involved in amyloidosis, innate immunity, inflammation, and apoptosis. We have previously described SAP in the male reproductive tract, where it occurs in seminal fluid, on spermatozoa, and in epididymal, seminal vesicle, and prostate tissue. In the present investigation, our aim was to characterize SAP in male reproduction. In short, we developed and evaluated an immunoass...

  1. Amyloid Oligomer Conformation in a Group of Natively Folded Proteins

    OpenAIRE

    Yoshiike, Yuji; Minai, Ryoichi; Matsuo, Yo; Chen, Yun-Ru; Kimura, Tetsuya; Takashima, Akihiko

    2008-01-01

    Recent in vitro and in vivo studies suggest that destabilized proteins with defective folding induce aggregation and toxicity in protein-misfolding diseases. One such unstable protein state is called amyloid oligomer, a precursor of fully aggregated forms of amyloid. Detection of various amyloid oligomers with A11, an anti-amyloid oligomer conformation-specific antibody, revealed that the amyloid oligomer represents a generic conformation and suggested that toxic ?-aggregation processes posse...

  2. Human serum amyloid P component is a single uncomplexed pentamer in whole serum.

    OpenAIRE

    Hutchinson, W.L.; Hohenester, E.; Pepys, M. B.

    2000-01-01

    BACKGROUND: Serum amyloid P component (SAP) is a universal constituent of amyloid deposits and contributes to their pathogenesis. SAP also has important normal functions in the handling of chromatin in vivo and resistance to bacterial infection. The atomic resolution crystal structure of SAP is known, but its physiological oligomeric assembly remains controversial. In the absence of calcium, isolated human SAP forms stable decamers composed of two cyclic disk-like pentamers interacting face t...

  3. Ligand-binding sites in human serum amyloid P component

    DEFF Research Database (Denmark)

    Heegaard, N.H.H.; Heegaard, Peter M. H.

    1996-01-01

    Amyloid P component (AP) is a naturally occurring glycoprotein that is found in serum and basement membranes, AP is also a component of all types of amyloid, including that found in individuals who suffer from Alzheimer's disease and Down's syndrome. Because AP has been found to bind strongly and specifically to certain glycosaminoglycans that are components of amyloid deposits, AP may play an important role in the maintenance of amyloid. In the present work, we isolated and identified two proteolytic fragments of AP that are responsible for its heparin-binding activity. Neither fragment corresponds to published heparin-binding sequences. The structural requirements for activity of the peptides (amino acid residues 27-38 and 192-203 of AP) were examined by means of solid-phase inhibition assays with synthetic peptides, AP-(192-203)-peptide inhibits the Ca2+-dependent binding of AP to heparin with an IC50 of 25 mu M, while the IC50 of AP-(27-38)-peptide and AP-(33-38)-peptide are 10 mu M and 2 mu M, respectively, The understanding of the structure and function of active AP peptides will be useful for development of amyloid-targeted diagnostics and therapeutics.

  4. Serum amyloid A inhibits RANKL-induced osteoclast formation.

    Science.gov (United States)

    Oh, Eunseo; Lee, Ha Young; Kim, Hak Jung; Park, Yoo Jung; Seo, Jeong Kon; Park, Joon Seong; Bae, Yoe-Sik

    2015-01-01

    When mouse bone marrow-derived macrophages were stimulated with serum amyloid A (SAA), which is a major acute-phase protein, there was strong inhibition of osteoclast formation induced by the receptor activator of nuclear factor kappaB ligand. SAA not only markedly blocked the expression of several osteoclast-associated genes (TNF receptor-associated factor 6 and osteoclast-associated receptor) but also strongly induced the expression of negative regulators (MafB and interferon regulatory factor 8). Moreover, SAA decreased c-fms expression on the cell surface via shedding of the c-fms extracellular domain. SAA also restrained the fusion of osteoclast precursors by blocking intracellular ATP release. This inhibitory response of SAA is not mediated by the well-known SAA receptors (formyl peptide receptor 2, Toll-like receptor 2 (TLR2) or TLR4). These findings provide insight into a novel inhibitory role of SAA in osteoclastogenesis and suggest that SAA is an important endogenous modulator that regulates bone homeostasis. PMID:26563612

  5. Neuronal overexpression of mutant amyloid precursor protein results in prominent deposition of cerebrovascular amyloid

    OpenAIRE

    Calhoun, Michael E; Burgermeister, Patrick; Phinney, Amie L.; Stalder, Martina; Tolnay, Markus; Wiederhold, Karl-Heinz; Abramowski, Dorothee; Sturchler-Pierrat, Christine; Sommer, Bernd; Staufenbiel, Matthias; Jucker, Mathias

    1999-01-01

    Transgenic mice that overexpress mutant human amyloid precursor protein (APP) exhibit one hallmark of Alzheimer’s disease pathology, namely the extracellular deposition of amyloid plaques. Here, we describe significant deposition of amyloid ? (A?) in the cerebral vasculature [cerebral amyloid angiopathy (CAA)] in aging APP23 mice that had striking similarities to that observed in human aging and Alzheimer’s disease. Amyloid deposition occurred preferentially in arterioles and capillaries and ...

  6. Serum Amyloid A Circulating Levels and Disease Activity in Patients with Juvenile Idiopathic Arthritis

    OpenAIRE

    Cantarini, Luca; Giani, Teresa; Fioravanti, Antonella; Iacoponi, Francesca; Simonini, Gabriele; Pagnini, Ilaria; Spreafico, Adriano; Chellini, Federico; Galeazzi, Mauro; Cimaz, Rolando

    2012-01-01

    The aim of our study was to evaluate the association between circulating levels of serum amyloid A protein (SAA) and disease activity in patients with juvenile idiopathic arthritis (JIA). Our study group included 41 JIA patients (9 male, 32 female), classified according to the International League of Associations for Rheumatology (ILAR) criteria (5); 16 had polyarticular onset disease and 25 had oligoarticular onset disease. Among 25 patients with oligoarticular disease, three had extended ol...

  7. Administration of perioperative penicillin reduces postoperative serum amyloid A response in horses being castrated standing

    DEFF Research Database (Denmark)

    Busk, Peter; Jacobsen, Stine; Martinussen, Torben

    2010-01-01

    Objectives: To compare postoperative in?ammatory responses in horses administered perioperative procaine penicillin and those not administered penicillin using acute phase protein serum amyloid A (SAA) as a marker of in?ammation. Study Design: Randomized clinical trial. Animals: Stallions (n = 50) castrated under ?eld conditions. Methods: SAA concentrations were determined on days 0, 3, and 8. Six horses were subsequently excluded because of elevated SAA concentrations on day 0. Of the remaining...

  8. Characterization of serum amyloid A (SAA) in rainbow trout using a new monoclonal antibody

    DEFF Research Database (Denmark)

    Kania, Per Walter; Chettri, Jiwan Kumar; Buchmann, Kurt

    2014-01-01

    Serum amyloid A (SAA) is an integral part of the innate immune response in mammals and considered to be important during the acute phase response. The present study was undertaken to elucidate the role of SAA protein in the innate immune response of rainbow trout. A monoclonal antibody raised against a recombinant peptide of rainbow trout SAA was characterized using Western blot, dot blot, ELISA and immunohistochemistry. SAA association with high density lipoprotein (HDL) complicated band identi...

  9. SERUM AMYLOID A IN RUMINANTS: DIAGNOSTIC VALUE AND FOOD CONTAMINATION ASSESSMENT

    OpenAIRE

    Pisani, Laura Francesca

    2010-01-01

    The aims of the work presented in this thesis were to investigate the bovine acute phase protein Serum Amyloid A, focussing on its value as safety marker in farm animals. SAA can be considered as a natural anti-inflammatory and immunomodulatory agent and local expression of SAA, at the site of the initial acute phase reaction, could protect against the deleterious effects of inflammation. In this study whether SAA can be isolated from tissues of bovine with clinical amyloidosis was i...

  10. Calumenin interacts with serum amyloid P component

    DEFF Research Database (Denmark)

    Vorum, H; Jacobsen, Christian; Honoré, Bent

    2000-01-01

    We recently reported the identification of human calumenin, a novel Ca(2+) binding, transformation-sensitive and secreted protein [Vorum et al. (1998) Biochim. Biophys. Acta 1386, 121-131; Vorum et al. (1999) Exp. Cell Res. 248, 473-481] belonging to the family of multiple EF-hand proteins of the secretory pathway that include reticulocalbin, ERC-55, Cab45 and crocalbin. In order to further investigate the extracellular functions of calumenin we immobilized the recombinant protein to a column. A...

  11. Interaction of serum amyloid P component with hexanoyl bis(d-proline) (CPHPC)

    Energy Technology Data Exchange (ETDEWEB)

    Kolstoe, Simon E. [University College London, Rowland Hill Street, London NW3 2PF (United Kingdom); Jenvey, Michelle C. [University of Southampton, Southampton SO17 1BJ (United Kingdom); Purvis, Alan [Imperial College London, London SW7 2AZ (United Kingdom); Light, Mark E. [University of Southampton, Southampton SO17 1BJ (United Kingdom); Thompson, Darren [University of Sussex, Falmer, Brighton BN1 9RQ (United Kingdom); Hughes, Peter; Pepys, Mark B.; Wood, Stephen P., E-mail: s.wood@ucl.ac.uk [University College London, Rowland Hill Street, London NW3 2PF (United Kingdom)

    2014-08-01

    Serum amyloid P component is a pentameric plasma glycoprotein that recognizes and binds to amyloid fibres in a calcium-dependent fashion and is likely to contribute to their deposition and persistence in vivo. Five molecules of the drug CPHPC avidly cross-link pairs of protein pentamers and the decameric complex is rapidly cleared in vivo. Crystal structures of the protein in complex with a bivalent drug and cadmium ions, which improve crystal quality, allow the definition of the preferred bound drug isomers. Under physiological conditions, the pentameric human plasma protein serum amyloid P component (SAP) binds hexanoyl bis(d-proline) (R-1-(6-[R-2-carboxy-pyrrolidin-1-yl]-6-oxo-hexanoyl) pyrrolidine-2-carboxylic acid; CPHPC) through its d-proline head groups in a calcium-dependent interaction. Cooperative effects in binding lead to a substantial enhancement of affinity. Five molecules of the bivalent ligand cross-link and stabilize pairs of SAP molecules, forming a decameric complex that is rapidly cleared from the circulation by the liver. Here, it is reported that X-ray analysis of the SAP complex with CPHPC and cadmium ions provides higher resolution detail of the interaction than is observed with calcium ions. Conformational isomers of CPHPC observed in solution by HPLC and by X-ray analysis are compared with the protein-bound form. These are discussed in relation to the development of CPHPC to provide SAP depletion for the treatment of amyloidosis and other indications.

  12. The porcine acute phase response to infection with Actinobacillus pleuropneumoniae. Haptoglobin, C-reactive protein, major acute phase protein and serum amyloid a protein are sensitive indicators of infection

    DEFF Research Database (Denmark)

    Heegaard, Peter M. H.; Klausen, Joan; Nielsen, J.P.; Gonzalez-Ramon, N.; Pineiro, M.; Lampreave, F.; Alava, M.A.

    1998-01-01

    In an experimental infection model mimicking acute Actinobacillus pleuropneumoniae (Ap) infection in swine (Sus scrofa) by aerosol inoculation, the development of a number of typical clinical signs was accompanied by a prototypic acute phase reaction encompassing fever and an acute phase protein response peaking at around 2 days after infection. Haptoglobin, C-reactive protein (CRP), and major acute phase protein (MAP) responded with large increases in serum levels, preceding the development of ...

  13. Immunohistochemical characterization of amyloid proteins in sural nerves and clinical associations in amyloid neuropathy.

    OpenAIRE

    Li, K.; Kyle, R. A.; Dyck, P.J.

    1992-01-01

    To test whether immunohistochemical characterization of proteins in amyloid deposits in biopsied sural nerves gives reliable and useful diagnostic information using commercially available reagents, biopsy specimens of sural nerves from 38 patients with amyloid neuropathy were studied. Transthyretin (TTR) was detected in the amyloid deposits of 11 nerves, lambda light chains (LC) in 8 nerves, kappa LC in 7 nerves, and both lambda and kappa LC in 3 nerves. In 9 nerves, the amyloid deposits were...

  14. Expression of serum amyloid a in equine wounds

    DEFF Research Database (Denmark)

    Sørensen, Mette Aamand; Jacobsen, Stine; Berg, Lise Charlotte

    2010-01-01

    OBJECTIVES Aberrant wound healing with formation of exuberant granulation tissue (EGT) occurs frequently in horses and may affect their athletic career and quality of life. The objective of the study was to determine mRNA expression levels of serum amyloid A (SAA) in normal and aberrant wound healing in horses. METHODS Experimental wounds were made in six horses on both metatarsi and on regio brachii. One limb was bandaged to provoke formation of EGT. Biopsies were collected on day 21 and were d...

  15. Organization and Biology of the Porcine Serum Amyloid A (SAA) Gene Cluster: Isoform Specific Responses to Bacterial Infection

    DEFF Research Database (Denmark)

    Olsen, Helle G; Skovgaard, Kerstin; Nielsen, Ole L; Leifsson, Páll S.; Jensen, Henrik E.; Iburg, Tine; Heegaard, Peter M. H.

    2013-01-01

    Serum amyloid A (SAA) is a prominent acute phase protein. Although its biological functions are debated, the wide species distribution of highly homologous SAA proteins and their uniform behavior in response to injury or inflammation in itself suggests a significant role for this protein. The pig is increasingly being used as a model for the study of inflammatory reactions, yet only little is known about how specific SAA genes are regulated in the pig during acute phase responses and other respo...

  16. Serum amyloid A  renal amyloidosis in a chronic subcutaneous (“skin popping”) heroin user

    Science.gov (United States)

    Cooper, Chad; Bilbao, Jorge E.; Said, Sarmad; Alkhateeb, Haider; Bizet, Jorge; Elfar, Ahmed; Davalos, Olinamyr; Meza, Ana T.; Hernandez, German T.

    2013-01-01

    Background: Systemic AA amyloidosis is a long-term complication of several chronic inflammatory disorders. Organ damage results from the extracellular deposition of proteolytic fragments of the acute-phase reactant serum amyloid A (SAA) as amyloid fibrils. Drug users that inject drug by a subcutaneous route (“skin popping”) have a higher chance of developing secondary amyloidosis. The kidneys, liver, and spleen are the main target organs of AA amyloid deposits. More than 90% of patients with renal amyloidosis will present with proteinuria, nephrotic syndrome, or renal function. Case presentation: A 37 year-old female presented to the hospital with a one-week history of pain and redness in her right axilla. Her relevant medical history included multiple skin abscesses secondary to “skin popping”, heroin abuse for 18 years, and hepatitis C. The physical examination revealed “skin popping” lesions, bilateral costovertebral angle tenderness, and bilateral knee swelling. The laboratory workup was significant for renal insufficiency with a serum creatinine of 5 mg/dL and 14.8 grams of urine protein per 1 gram of urine creatinine. The renal biopsy findings were consistent with a diagnosis of renal amyloidosis due to serum amyloid A deposition and acute tubulointerstitial nephritis. Conclusions: AA renal amyloidosis among heroin addicts seems to be associated with chronic suppurative skin infection secondary to “skin popping”. It is postulated that the chronic immunologic stimulation by one or more exogenous antigens or multiple acute inflammatory episodes is an important factor in the pathogenesis of amyloidosis in these patients. Therefore, AA renal amyloidosis should always be considered in chronic heroin users presenting with proteinuria and renal impairment. PMID:24475449

  17. A unique biofilm in human deep mycoses: fungal amyloid is bound by host serum amyloid P component

    Science.gov (United States)

    Garcia-Sherman, Melissa C; Lundberg, Tracy; Sobonya, Richard E; Lipke, Peter N; Klotz, Stephen A

    2015-01-01

    Background/Objectives We have demonstrated the presence of Candida cell surface amyloids that are important in aggregation of fungi and adherence to tissue. Fungal amyloid was present in invasive human candidal infections and host serum amyloid P component (SAP) bound to the fungal amyloid. SAP is a protease-resistant glycoprotein that binds avidly to amyloid and interferes with host defence, especially against bacterial pathogens for which neutrophils are important. In this study, we investigated whether biofilm of fungal amyloid and SAP was a feature of other disseminated fungal infections. Methods Tissue specimens from 15 autopsies were systematically evaluated with multiple histochemical stains including thioflavin T and Congo red (dyes that stain amyloid), as well as antibody to SAP. We studied specimens with disseminated aspergillosis, mucormycosis and coccidioidomycosis. The structure of the lesions, host inflammatory cells and the presence of fungal amyloid and SAP were determined. Results The structure of the lesions was characteristic in aspergillosis (‘starburst’) and mucormycosis (closely apposed bundles of hyphae). Host inflammatory cells were absent or few in number within these lesions. In Coccidioides lesions, host inflammation was sparse as well. Fungal amyloid was a prominent feature of all lesions along with abundant SAP bound to hyphae and spherules. Fungal amyloid and SAP perhaps contributed to persistence in caseous necrosis lesions. SAP also bound to Aspergillus and Mucorales amyloid in vitro. Conclusions A biofilm including amyloid and SAP is present in invasive fungal infections. This biofilm may dampen host defence leading to the characteristic sparse inflammatory reaction found in these infections. PMID:26366292

  18. Apple Procyanidins Suppress Amyloid ?-Protein Aggregation

    OpenAIRE

    Toda, Toshihiko; Sunagawa, Tadahiro; Kanda, Tomomasa; Tagashira, Motoyuki; Shirasawa, Takuji; Shimizu, Takahiko

    2011-01-01

    Procyanidins (PCs) are major components of the apple polyphenols (APs). We previously reported that treatment with PC extended the mean lifespan of Caenorhabditis elegans (Sunagawa et al., 2011). In order to estimate the neuroprotective effects of PC, we investigated the antiaggregative activity of PC on amyloid ?-protein (A?) aggregation, which is a pathological hallmark of Alzheimer's disease. We herein report that PC significantly suppressed A?42 aggregation and dissociated A?42 aggregates...

  19. Novel mediators of amyloid precursor protein signaling

    OpenAIRE

    Swistowski, Andrzej; Zhang, Qiang; Orcholski, Mark E.; Crippen, Danielle; Vitelli, Cathy; Kurakin, Alexei; Bredesen, Dale E

    2009-01-01

    Multiple recent reports implicate amyloid precursor protein (APP) signaling in the pathogenesis of Alzheimer's disease, but the APP-dependent signaling network involved has not been defined. Here we report a novel consensus sequence for interaction with the PDZ-1 and PDZ-2 domains of the APP-interacting proteins Mint1, Mint2, and Mint3 (X11?, X11?, and X11?), and multiple novel interactors for these proteins, with the finding that transcriptional co-activators are highly represented among the...

  20. Serum amyloid A  renal amyloidosis in a chronic subcutaneous (“skin popping”) heroin user

    OpenAIRE

    Cooper, Chad; Bilbao, Jorge E.; Said, Sarmad; Alkhateeb, Haider; Bizet, Jorge; Elfar, Ahmed; Davalos, Olinamyr; Meza, Ana T.; German T. Hernandez

    2013-01-01

    Background: Systemic AA amyloidosis is a long-term complication of several chronic inflammatory disorders. Organ damage results from the extracellular deposition of proteolytic fragments of the acute-phase reactant serum amyloid A (SAA) as amyloid fibrils. Drug users that inject drug by a subcutaneous route (“skin popping”) have a higher chance of developing secondary amyloidosis. The kidneys, liver, and spleen are the main target organs of AA amyloid deposits. More than 90% of patients...

  1. Overexpression of Monocyte Chemotactic Protein-1/CCL2 in ?-Amyloid Precursor Protein Transgenic Mice Show Accelerated Diffuse ?-Amyloid Deposition

    OpenAIRE

    Yamamoto, Masaru; Horiba, Masahide; Buescher, James L.; Huang, DeReng; Gendelman, Howard E; Ransohoff, Richard M.; Ikezu, Tsuneya

    2005-01-01

    Microglia accumulation at the site of amyloid plaques is a strong indication that microglia play a major role in Alzheimer’s disease pathogenesis. However, how microglia affect amyloid-? peptide (A?) deposition remains poorly understood. To address this question, we developed a novel bigenic mouse that overexpresses both amyloid precursor protein (APP) and monocyte chemotactic protein-1 (MCP-1; CCL2 in systematic nomenclature). CCL2 expression, driven by the glial fibrillary acidic protein pr...

  2. Amyloid ?-sheet mimics that antagonize protein aggregation and reduce amyloid toxicity

    Science.gov (United States)

    Cheng, Pin-Nan; Liu, Cong; Zhao, Minglei; Eisenberg, David; Nowick, James S.

    2012-11-01

    The amyloid protein aggregation associated with diseases such as Alzheimer's, Parkinson's and type II diabetes (among many others) features a bewildering variety of ?-sheet-rich structures in transition from native proteins to ordered oligomers and fibres. The variation in the amino-acid sequences of the ?-structures presents a challenge to developing a model system of ?-sheets for the study of various amyloid aggregates. Here, we introduce a family of robust ?-sheet macrocycles that can serve as a platform to display a variety of heptapeptide sequences from different amyloid proteins. We have tailored these amyloid ?-sheet mimics (ABSMs) to antagonize the aggregation of various amyloid proteins, thereby reducing the toxicity of amyloid aggregates. We describe the structures and inhibitory properties of ABSMs containing amyloidogenic peptides from the amyloid-? peptide associated with Alzheimer's disease, ?2-microglobulin associated with dialysis-related amyloidosis, ?-synuclein associated with Parkinson's disease, islet amyloid polypeptide associated with type II diabetes, human and yeast prion proteins, and Tau, which forms neurofibrillary tangles.

  3. Serum amyloid a gene expression and immunohistochemical localization in rainbow trout, Oncorhynchus mykiss, infected by Yersinia ruckeri

    DEFF Research Database (Denmark)

    Kania, Per Walter; Buchmann, Kurt; Chettri, Jiwan Kumar

    2013-01-01

    Serum amyloid A (SAA) is an integral part of the innate immune response in general and in particular the acute phase response. SAA belongs to a highly conserved group of apolipoproteins reported from different groups of organisms such as mammals, birds, fish and even invertebrates. The present study was undertaken to elucidate the role of SAA protein in the innate immune response of rainbow trout. For this purpose a monoclonal antibody was raised against a recombinant peptide of rainbow trout SA...

  4. Regulation of Serum Amyloid A3 (SAA3) in Mouse Colonic Epithelium and Adipose Tissue by the Intestinal Microbiota

    OpenAIRE

    Reigstad, Christopher S.; Lundén, Gunnel Östergren; Felin, Jenny; Bäckhed, Fredrik

    2009-01-01

    The gut microbiota has been proposed as an environmental factor that affects the development of metabolic and inflammatory diseases in mammals. Recent reports indicate that gut bacteria-derived lipopolysaccharide (LPS) can initiate obesity and insulin resistance in mice; however, the molecular interactions responsible for microbial regulation of host metabolism and mediators of inflammation have not been studied in detail. Hepatic serum amyloid A (SAA) proteins are markers and proposed mediat...

  5. Statistical Mechanical Treatments of Protein Amyloid Formation

    CERN Document Server

    Schreck, John S

    2013-01-01

    Protein aggregation is an important field of investigation because it is closely related to the problem of neurodegenerative diseases, to the development of biomaterials, and to the growth of cellular structures such as cyto-skeleton. Self-aggregation of protein amyloids, for example, is a complicated process involving many species and levels of structures. This complexity, however, can be dealt with using statistical mechanical tools, such as free energies, partition functions, and transfer matrices. In this article, we review general strategies for studying protein aggregation using statistical mechanical approaches and show that canonical and grand canonical ensembles can be used in such approaches. The grand canonical approach is particularly convenient since competing pathways of assembly and dis-assembly can be considered simultaneously. Another advantage of using statistical mechanics is that numerically exact solutions can be obtained for all of the thermodynamic properties of fibrils, such as the amo...

  6. Serum amyloid A and haptoglobin concentrations in serum and peritoneal fluid of healthy horses and horses with acute abdominal pain

    DEFF Research Database (Denmark)

    Pihl, Tina Holberg; Andersen, Pia Haubro; Kjelgaard-Hansen, Mads; Mørck, Nina Brinch; Jacobsen, Stine

    2013-01-01

    BACKGROUND: Peritoneal fluid (PF) analysis is a valuable diagnostic tool in equine medicine. Markers such as serum amyloid A (SAA) and haptoglobin (Hp) could facilitate the diagnosis of inflammatory abdominal conditions. OBJECTIVES: The objectives were to (1) establish reference intervals (RI) for SAA and Hp in serum and PF in healthy horses, (2) compare SAA and Hp concentrations between healthy horses and horses with colic, and (3) to assess the correlation between serum and PF concentrations. ...

  7. Soluble aggregates of the amyloid-? peptide are trapped by serum albumin to enhance amyloid-? activation of endothelial cells

    Directory of Open Access Journals (Sweden)

    Gonzalez-Velasquez Francisco J

    2009-04-01

    Full Text Available Abstract Background Self-assembly of the amyloid-? peptide (A? has been implicated in the pathogenesis of Alzheimer's disease (AD. As a result, synthetic molecules capable of inhibiting A? self-assembly could serve as therapeutic agents and endogenous molecules that modulate A? self-assembly may influence disease progression. However, increasing evidence implicating a principal pathogenic role for small soluble A? aggregates warns that inhibition at intermediate stages of A? self-assembly may prove detrimental. Here, we explore the inhibition of A?1–40 self-assembly by serum albumin, the most abundant plasma protein, and the influence of this inhibition on A?1–40 activation of endothelial cells for monocyte adhesion. Results It is demonstrated that serum albumin is capable of inhibiting in a dose-dependent manner both the formation of A?1–40 aggregates from monomeric peptide and the ongoing growth of A?1–40 fibrils. Inhibition of fibrillar A?1–40 aggregate growth is observed at substoichiometric concentrations, suggesting that serum albumin recognizes aggregated forms of the peptide to prevent monomer addition. Inhibition of A?1–40 monomer aggregation is observed down to stoichiometric ratios with partial inhibition leading to an increase in the population of small soluble aggregates. Such partial inhibition of A?1–40 aggregation leads to an increase in the ability of resulting aggregates to activate endothelial cells for adhesion of monocytes. In contrast, A?1–40 activation of endothelial cells for monocyte adhesion is reduced when more complete inhibition is observed. Conclusion These results demonstrate that inhibitors of A? self-assembly have the potential to trap small soluble aggregates resulting in an elevation rather than a reduction of cellular responses. These findings provide further support that small soluble aggregates possess high levels of physiological activity and underscore the importance of resolving the effect of A? aggregation inhibitors on aggregate size.

  8. Relative serum amyloid A (SAA) values: the influence of SAA1 genotypes and corticosteroid treatment in Japanese patients with rheumatoid arthritis

    OpenAIRE

    Yamada, T.; Okuda, Y.; Takasugi, K.; Itoh, K.(Department of Physics, University of Tokyo, 113-0033, Tokyo, Japan); Igari, J

    2001-01-01

    OBJECTIVES—(1) To determine whether serum concentration of serum amyloid A (SAA) protein is influenced by the SAA1 allele in Japanese patients with rheumatoid arthritis (RA) as previously shown in a healthy control group; and (2) to analyse what factors, based on such an allelic bias, influence the relative SAA values of those patients.?METHODS—SAA and C reactive protein (CRP) concentrations together with SAA1 genotypes were determined in 316 Japanese patients with RA. The relative SAA values...

  9. Formation of soluble amyloid oligomers and amyloid fibrils by the multifunctional protein vitronectin

    Directory of Open Access Journals (Sweden)

    Langen Ralf

    2008-10-01

    Full Text Available Abstract Background The multifunctional protein vitronectin is present within the deposits associated with Alzheimer disease (AD, age-related macular degeneration (AMD, atherosclerosis, systemic amyloidoses, and glomerulonephritis. The extent to which vitronectin contributes to amyloid formation within these plaques, which contain misfolded, amyloidogenic proteins, and the role of vitronectin in the pathophysiology of the aforementioned diseases is currently unknown. The investigation of vitronectin aggregation is significant since the formation of oligomeric and fibrillar structures are common features of amyloid proteins. Results We observed vitronectin immunoreactivity in senile plaques of AD brain, which exhibited overlap with the amyloid fibril-specific OC antibody, suggesting that vitronectin is deposited at sites of amyloid formation. Of particular interest is the growing body of evidence indicating that soluble nonfibrillar oligomers may be responsible for the development and progression of amyloid diseases. In this study we demonstrate that both plasma-purified and recombinant human vitronectin readily form spherical oligomers and typical amyloid fibrils. Vitronectin oligomers are toxic to cultured neuroblastoma and retinal pigment epithelium (RPE cells, possibly via a membrane-dependent mechanism, as they cause leakage of synthetic vesicles. Oligomer toxicity was attenuated in RPE cells by the anti-oligomer A11 antibody. Vitronectin fibrils contain a C-terminal protease-resistant fragment, which may approximate the core region of residues essential to amyloid formation. Conclusion These data reveal the propensity of vitronectin to behave as an amyloid protein and put forth the possibilities that accumulation of misfolded vitronectin may contribute to aggregate formation seen in age-related amyloid diseases.

  10. Interaction of intracellular ? amyloid peptide with chaperone proteins

    OpenAIRE

    Fonte, Virginia; Kapulkin, Wadim Jan; Taft, Andrew; Fluet, Amy; FRIEDMAN, DAVID; Link, Christopher D.

    2002-01-01

    Expression of the human ? amyloid peptide (A?) in transgenic Caenorhabditis elegans animals can lead to the formation of intracellular immunoreactive deposits as well as the formation of intracellular amyloid. We have used this model to identify proteins that interact with intracellular A? in vivo. Mass spectrometry analysis of proteins that specifically coimmunoprecipitate with A? has identified six likely chaperone proteins: two members of the HSP70 family, three ?B-...

  11. Efflux transport of serum amyloid P component at the blood–brain barrier

    OpenAIRE

    Veszelka, Szilvia; Laszy, Judit; Pázmány, Tamás; Ne?meth, La?szlo?; Obál, Izabella; Fábián, László; Szabó, Gábor; Ábrahám, Csongor S.; Deli, Mária A.; Urbányi, Zoltán

    2013-01-01

    Serum amyloid P component (SAP), a member of the innate immune system, does not penetrate the brain in physiological conditions; however, SAP is a stabilizing component of the amyloid plaques in neurodegenerative diseases. We investigated the cerebrovascular transport of human SAP in animal experiments and in culture blood–brain barrier (BBB) models. After intravenous injection, no SAP could be detected by immunohistochemistry or ELISA in healthy rat brains. Salmonella typhi...

  12. Influenza virus infection is not affected by serum amyloid P component.

    OpenAIRE

    HERBERT, J.; Hutchinson, W.L.; CARR, J; Ives, J.; Jakob-Roetne, R.; Yamamura, K; Suzuki, M.; Pepys, M. B.

    2002-01-01

    BACKGROUND: Binding of serum amyloid P component (SAP) to its ligands, including bacteria, chromatin and amyloid fibrils, protects them from degradation, is anti-opsonic and anti-immunogenic. SAP thereby enhances the virulence of pathogenic bacteria to which it binds. However SAP also contributes to host resistance against bacteria to which it does not bind. Human SAP has been reported to bind to the influenza virus and inhibit viral invasion of cells in tissue culture. We therefore investiga...

  13. Amyloid-Like Protein Inclusions in Tobacco Transgenic Plants

    Science.gov (United States)

    Villar-Piqué, Anna; Sabaté, Raimon; Lopera, Oriol; Gibert, Jordi; Torne, Josep Maria; Santos, Mireya; Ventura, Salvador

    2010-01-01

    The formation of insoluble protein deposits in human tissues is linked to the onset of more than 40 different disorders, ranging from dementia to diabetes. In these diseases, the proteins usually self-assemble into ordered ?-sheet enriched aggregates known as amyloid fibrils. Here we study the structure of the inclusions formed by maize transglutaminase (TGZ) in the chloroplasts of tobacco transplastomic plants and demonstrate that they have an amyloid-like nature. Together with the evidence of amyloid structures in bacteria and fungi our data argue that amyloid formation is likely a ubiquitous process occurring across the different kingdoms of life. The discovery of amyloid conformations inside inclusions of genetically modified plants might have implications regarding their use for human applications. PMID:21049018

  14. Statistical Mechanical Treatments of Protein Amyloid Formation

    Directory of Open Access Journals (Sweden)

    John S. Schreck

    2013-08-01

    Full Text Available Protein aggregation is an important field of investigation because it is closely related to the problem of neurodegenerative diseases, to the development of biomaterials, and to the growth of cellular structures such as cyto-skeleton. Self-aggregation of protein amyloids, for example, is a complicated process involving many species and levels of structures. This complexity, however, can be dealt with using statistical mechanical tools, such as free energies, partition functions, and transfer matrices. In this article, we review general strategies for studying protein aggregation using statistical mechanical approaches and show that canonical and grand canonical ensembles can be used in such approaches. The grand canonical approach is particularly convenient since competing pathways of assembly and dis-assembly can be considered simultaneously. Another advantage of using statistical mechanics is that numerically exact solutions can be obtained for all of the thermodynamic properties of fibrils, such as the amount of fibrils formed, as a function of initial protein concentration. Furthermore, statistical mechanics models can be used to fit experimental data when they are available for comparison.

  15. The metazoan protein disaggregase and amyloid depolymerase system

    Science.gov (United States)

    Torrente, Mariana P; Shorter, James

    2013-01-01

    A baffling aspect of metazoan proteostasis is the lack of an Hsp104 ortholog that rapidly disaggregates and reactivates misfolded polypeptides trapped in stress induced disordered aggregates, preamyloid oligomers, or amyloid fibrils. By contrast, in bacteria, protozoa, chromista, fungi, and plants, Hsp104 orthologs are highly conserved and confer huge selective advantages in stress tolerance. Moreover, in fungi, the amyloid remodeling activity of Hsp104 has enabled deployment of prions for various beneficial modalities. Thus, a longstanding conundrum has remained unanswered: how do metazoan cells renature aggregated proteins or resolve amyloid fibrils without Hsp104? Here, we highlight recent advances that unveil the metazoan protein-disaggregase machinery, comprising Hsp110, Hsp70, and Hsp40, which synergize to dissolve disordered aggregates, but are unable to rapidly solubilize stable amyloid fibrils. However, Hsp110, Hsp70, and Hsp40 exploit the slow monomer exchange dynamics of amyloid, and can slowly depolymerize amyloid fibrils from their ends in a manner that is stimulated by small heat shock proteins. Upregulation of this system could have key therapeutic applications in various protein-misfolding disorders. Intriguingly, yeast Hsp104 can interface with metazoan Hsp110, Hsp70, and Hsp40 to rapidly eliminate disease associated amyloid. Thus, metazoan proteostasis is receptive to augmentation with exogenous disaggregases, which opens a number of therapeutic opportunities. PMID:24401655

  16. Amyloid-Like Protein Inclusions in Tobacco Transgenic Plants

    OpenAIRE

    Villar-Piqué, Anna; Sabaté, Raimon; Lopera, Oriol; Gibert, Jordi; Torne, Josep Maria; Santos, Mireya; Ventura, Salvador

    2010-01-01

    The formation of insoluble protein deposits in human tissues is linked to the onset of more than 40 different disorders, ranging from dementia to diabetes. In these diseases, the proteins usually self-assemble into ordered ?-sheet enriched aggregates known as amyloid fibrils. Here we study the structure of the inclusions formed by maize transglutaminase (TGZ) in the chloroplasts of tobacco transplastomic plants and demonstrate that they have an amyloid-like nature. Together with the evidence ...

  17. Modeling of chemical inhibition from amyloid protein aggregation kinetics

    OpenAIRE

    Vázquez, José Antonio

    2014-01-01

    Backgrounds The process of amyloid proteins aggregation causes several human neuropathologies. In some cases, e.g. fibrillar deposits of insulin, the problems are generated in the processes of production and purification of protein and in the pump devices or injectable preparations for diabetics. Experimental kinetics and adequate modelling of chemical inhibition from amyloid aggregation are of practical importance in order to study the viable processing, formulation and storage as well as to...

  18. Serum Amyloid A as a Predictive Marker for Radiation Pneumonitis in Lung Cancer Patients

    International Nuclear Information System (INIS)

    Purpose: To investigate serum markers associated with radiation pneumonitis (RP) grade ?3 in patients with lung cancer who were treated with radiation therapy. Methods and Materials: Pretreatment serum samples from patients with stage Ib-IV lung cancer who developed RP within 1 year after radiation therapy were analyzed to identify a proteome marker able to stratify patients prone to develop severe RP by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Dosimetric parameters and 3 biological factors were compared. Results: Serum samples from 16 patients (28%) with severe RP (grade 3-4) and 42 patients (72%) with no or mild RP (grade 0-2) were collected for analysis. All patients received a median of 54 Gy (range, 42-70 Gy) of three-dimensional conformal radiation therapy with a mean lung dose (MLD) of 1502 cGy (range, 700-2794 cGy). An m/z peak of 11,480 Da was identified by SELDI-TOF-MS, and serum amyloid A (SAA) was the primary splitter serum marker. The receiver operating characteristic area under the curve of SAA (0.94; 95% confidence interval [CI], 0.87-1.00) was higher than those of C-reactive protein (0.83; 95% CI, 0.72-0.94), interleukin-6 (0.79; 95% CI, 0.65-0.94), and MLD (0.57; 95% CI, 0.37-0.77). The best sensitivity and specificity of combined SAA and MLD for predicting RP were 88.9% and 96.0%, respectively. Conclusions: Baseline SAA could be used as an auxiliary marker for predicting severe RP. Extreme care should be taken to limit the lung irradiation dose in patients with high SAA

  19. Serum Amyloid A as a Predictive Marker for Radiation Pneumonitis in Lung Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu-Shan [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Department of Animal Science, National Ilan University, Ilan, Taiwan (China); Chang, Heng-Jui [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Chang, Yue-Cune [Department of Mathematics, Tamkang University, Taipei, Taiwan (China); Huang, Su-Chen; Ko, Hui-Ling; Chang, Chih-Chia [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Yeh, Yu-Wung; Jiang, Jiunn-Song [Department of Chest Medicine, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Lee, Cheng-Yen; Chi, Mau-Shin [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Chi, Kwan-Hwa, E-mail: M006565@ms.skh.org.tw [Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan (China); Institute of Radiation Science and School of Medicine, National Yang-Ming University, Taipei, Taiwan (China)

    2013-03-01

    Purpose: To investigate serum markers associated with radiation pneumonitis (RP) grade ?3 in patients with lung cancer who were treated with radiation therapy. Methods and Materials: Pretreatment serum samples from patients with stage Ib-IV lung cancer who developed RP within 1 year after radiation therapy were analyzed to identify a proteome marker able to stratify patients prone to develop severe RP by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Dosimetric parameters and 3 biological factors were compared. Results: Serum samples from 16 patients (28%) with severe RP (grade 3-4) and 42 patients (72%) with no or mild RP (grade 0-2) were collected for analysis. All patients received a median of 54 Gy (range, 42-70 Gy) of three-dimensional conformal radiation therapy with a mean lung dose (MLD) of 1502 cGy (range, 700-2794 cGy). An m/z peak of 11,480 Da was identified by SELDI-TOF-MS, and serum amyloid A (SAA) was the primary splitter serum marker. The receiver operating characteristic area under the curve of SAA (0.94; 95% confidence interval [CI], 0.87-1.00) was higher than those of C-reactive protein (0.83; 95% CI, 0.72-0.94), interleukin-6 (0.79; 95% CI, 0.65-0.94), and MLD (0.57; 95% CI, 0.37-0.77). The best sensitivity and specificity of combined SAA and MLD for predicting RP were 88.9% and 96.0%, respectively. Conclusions: Baseline SAA could be used as an auxiliary marker for predicting severe RP. Extreme care should be taken to limit the lung irradiation dose in patients with high SAA.

  20. The acute phase response of haptoglobin and serum amyloid A (SAA) in cattle undergoing experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Heegaard, Peter M. H.; Godson, D.L.; Toussaint, M.J.M.; Tjørnehøj, Kirsten; Larsen, Lars Erik; Viuff, B.; Rønsholt, Leif

    2000-01-01

    The ability of a pure virus infection to induce an acute phase protein response is of interest as viral infections are normally considered to be less efficient in inducing an acute phase protein response than bacterial infections. This was studied in a bovine model for infection with bovine respiratory syncytial virus (BRSV), analysing the induction of the two most dominant bovine acute phase proteins haptoglobin and serum amyloid A (SAA). Strong and reproducible acute phase responses were detec...

  1. Brazilin inhibits amyloid ?-protein fibrillogenesis, remodels amyloid fibrils and reduces amyloid cytotoxicity

    Science.gov (United States)

    Du, Wen-Jie; Guo, Jing-Jing; Gao, Ming-Tao; Hu, Sheng-Quan; Dong, Xiao-Yan; Han, Yi-Fan; Liu, Fu-Feng; Jiang, Shaoyi; Sun, Yan

    2015-01-01

    Soluble amyloid ?-protein (A?) oligomers, the main neurotoxic species, are predominantly formed from monomers through a fibril-catalyzed secondary nucleation. Herein, we virtually screened an in-house library of natural compounds and discovered brazilin as a dual functional compound in both A?42 fibrillogenesis inhibition and mature fibril remodeling, leading to significant reduction in A?42 cytotoxicity. The potent inhibitory effect of brazilin was proven by an IC50 of 1.5 +/- 0.3 ?M, which was smaller than that of (-)-epigallocatechin gallate in Phase III clinical trials and about one order of magnitude smaller than those of curcumin and resveratrol. Most importantly, it was found that brazilin redirected A?42 monomers and its mature fibrils into unstructured A? aggregates with some ?-sheet structures, which could prevent both the primary nucleation and the fibril-catalyzed secondary nucleation. Molecular simulations demonstrated that brazilin inhibited A?42 fibrillogenesis by directly binding to A?42 species via hydrophobic interactions and hydrogen bonding and remodeled mature fibrils by disrupting the intermolecular salt bridge Asp23-Lys28 via hydrogen bonding. Both experimental and computational studies revealed a different working mechanism of brazilin from that of known inhibitors. These findings indicate that brazilin is of great potential as a neuroprotective and therapeutic agent for Alzheimer's disease.

  2. The physico-chemical, antigenic, and functional heterogeneity of human serum amyloid A

    International Nuclear Information System (INIS)

    In the present study we attempted to develop a rapid method to isolate serum amyloid A isomers (SAA is.) and to determine whether this physicochemical heterogeneity corresponds to an antigenic and functional one. Pure human low molecular SAA (SAAL) was prepared from the serum of 6 patients (pts.) using standard techniques. Preparative isoelectric focusing in agarose/sephadex gels was used to separate SAAL is. Monoclonal antibodies (m. abs.) to SAAL and to AA were prepared by hybridization of P3XU-1 nonsecretory murine myeloma cells with murine spleen cells from Balb/c mice immunized with pooled SAAL and AA respectively. Four distinctly migrating SAAL isomers with PI's of 4.9, 5.8, 6.6, and 7.2 were isolated from 6 pts. while only three isomers were separated from the pt. with myasthenia gravis. Four m. abs. to SAAL, one to AA, six m. abs. to SAAL-2 is. and one to SAAL-1 is. were generated in murine ascitic fluid. Dishes coated with the four human SAA is., human AA, various mammalian and human proteins as well as with serum from 31 pts. with metastatic Ca. and 23 pts. with inflammatory diseases (ID) were reacted with the m. abs. The amount of binding was determined using 125I labelled goat antimouse serum. The m. abs. to SAA were found specific for human SAA recognizing two different patterns in relationship to the intensity of binding to SAA is. One of them (7A2-43) had a greater affinity for SAA from pts with ID, while the other (5A6-5) reacted stronger with SAA from pts with metastatic Ca

  3. Serum amyloid A and haptoglobin concentrations in serum and peritoneal fluid of healthy horses and horses with acute abdominal pain

    DEFF Research Database (Denmark)

    Pihl, Tina Holberg; Andersen, Pia Haubro

    2013-01-01

    BACKGROUND: Peritoneal fluid (PF) analysis is a valuable diagnostic tool in equine medicine. Markers such as serum amyloid A (SAA) and haptoglobin (Hp) could facilitate the diagnosis of inflammatory abdominal conditions. OBJECTIVES: The objectives were to (1) establish reference intervals (RI) for SAA and Hp in serum and PF in healthy horses, (2) compare SAA and Hp concentrations between healthy horses and horses with colic, and (3) to assess the correlation between serum and PF concentrations. METHODS: Serum amyloid A and Hp concentrations were determined by automated assays in prospectively enrolled healthy reference horses and horses with colic. RIs were calculated, group concentrations were compared by Student's t-test, and Pearson's correlation for serum and PF concentrations were determined. RESULTS: In healthy horses (n = 62) the measurements for SAA were below the detection limit (0.5 mg/L) in 94% of serum samples and 98% of PF samples. Horses with colic (n = 61) had statistically significantly increased SAA concentrations in serum (P 

  4. Haptoglobin and serum amyloid a in subacute ruminal acidosis in goats

    Directory of Open Access Journals (Sweden)

    F.H.D. González

    2010-12-01

    Full Text Available Ruminal acidosis is a frequent disorder that occurs in goats as a consequence of feedingmistakes in animals not adapted to a diet of easily fermentable carbohydrates. The subacuteform of the disease is difficult to diagnose because no apparent signs are shownand the acid-base parameters may remain within the normal range. The present studyaimed at testing the hypothesis that haptoglobin (Hp and serum amyloid A (SAA,the two major acute phase proteins in ruminants, may be useful as markers of subacuteacidosis in goats.A subacute acidosis was induced in six Murciano-Granadina goats through a diet of60% mixed feed-40% alfalfa hay offered during 5 days to goats not adapted to eatmixed feed. Two goats were rumen-fistulated to investigate the effect of feeding onruminal pH. Sampling of blood and urine of all animals was done before the inductionof the acidosis, during 5 days after the onset of induction and for 18 days after theinduction (recovery period.Ruminal pH in the fistulated goats dropped to less than 5.5 during the inductionperiod, and half of the goats had diarrhea on the third day after the induction of acidosis.Acid-base parameters showed that the acid-base compensatory mechanisms wereefficient in maintaining the equilibrium. Serum Hp had a moderate increase duringthe induction period, while SAA did not change. These results suggest that Hp mightbe a potential marker for ruminal acidosis in goats.

  5. Kinetics of local and systemic isoforms of serum amyloid A in bovine mastitic milk

    DEFF Research Database (Denmark)

    Jacobsen, Stine; Niewold, T.A.; Kornalijnslijper, E.; Toussaint, M.J.M; Gruys, E.

    2005-01-01

    The aim of the present study was to characterise the serum amyloid A (SAA) response to intramammary inoculation of Escherichia coli and to examine the distribution of hepatically and extrahepatically pruduced SAA isoforms in plasma and milk fra cows with mastitis.

  6. Serum amyloid P component binds to influenza A virus haemagglutinin and inhibits the virus infection in vitro

    DEFF Research Database (Denmark)

    Andersen, Ove; Vilsgaard Ravn, K; Juul Sørensen, I; Jonson, G; Holm Nielsen, E; Svehag, SE

    1997-01-01

    Serum amyloid P component (SAP) is a member of the phylogenetically conserved and structurally related group of proteins called pentraxins. SAP exhibits multispecific calcium-dependent binding to oligosaccharides with terminal N-acetyl-galactosamine, mannose and glucuronic acid. The authors report that SAP can bind to influenza A virus and inhibit agglutination of erythrocytes mediated by the virus subtypes H1N1, H2N2 and H3N2. SAP also inhibits the production of haemagglutinin (HA) an the cytop...

  7. Prion amyloid structure explains templating: how proteins can be genes

    OpenAIRE

    Wickner, Reed B.; Shewmaker, Frank; Edskes, Herman; Kryndushkin, Dmitry; Nemecek, Julie; McGlinchey, Ryan; Bateman, David; Winchester, Chia-Lin

    2010-01-01

    The yeast and fungal prions determine heritable and infectious traits, and are thus genes composed of protein. Most prions are inactive forms of a normal protein as it forms a self-propagating filamentous ? – sheet - rich polymer structure called amyloid. Remarkably, a single prion protein sequence can form two or more faithfully inherited prion variants, in effect alleles of these genes. What protein structure explains this protein-based inheritance? Using solid-state NMR, we showed that the...

  8. Investigation of the solubility and the potentials for purification of serum amyloid A (SAA) from equine acute phase serum

    DEFF Research Database (Denmark)

    Christensen, Michelle Brønniche; Sørensen, Jens Christian; Jacobsen, Stine; Kjelgaard-Hansen, Mads

    2013-01-01

    BACKGROUND: Serum amyloid A (SAA) is useful as a diagnostic marker of systemic inflammation in horses, but only heterologous assays based on non-equine calibration and standardization are available for measurements of equine SAA. More accurate measurements could be obtained using purified species-specific SAA in native conformation for assay calibration and standardization. Further knowledge about the biochemical properties of SAA would facilitate a future production of native species-specific c...

  9. Measuring Serum Amyloid A for Infection Prediction in Aneurysmal Subarachnoid Hemorrhage.

    Science.gov (United States)

    Azurmendi, Leire; Degos, Vincent; Tiberti, Natalia; Kapandji, Natacha; Sanchez, Paola; Sarrafzadeh, Asita; Puybasset, Louis; Turck, Natacha; Sanchez, Jean-Charles

    2015-09-01

    Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high rates of mortality and morbidity. Nosocomial infections, such as pneumonia or urinary tract infections, are among the main causes of worsening outcomes and death. The aim of this study was to discover a biomarker to predict infection in aSAH patients. For this purpose, the plasma of infected and noninfected patients was compared using quantitative mass spectrometry. The most interesting differentially expressed proteins were selected for validation by immunoassays on plasma samples taken from patients (n = 81) over 10 days of hospitalization. Predictive performances were established using Mann-Whitney U tests and receiver operating characteristic curves. Quantitative proteomics identified 17 significantly regulated proteins. Of these, levels of serum amyloid A (SAA) were significantly higher in infected patients (p < 0.007). ELISA confirmed that the concentrations were significantly higher (p < 0.002) already at hospital admission in patients who subsequently developed an infection during their hospitalization, (AUC of 76%) for a cutoff value of 90.9 ?g/mL. Our data suggested that measuring SAA could be an efficient means of detecting patients susceptible of developing an infection during hospitalization after an aSAH. Its predictive capacity could lead to earlier antibiotherapy, improved patient management, and potentially better long-term outcomes. PMID:26198378

  10. The liver in systemic amyloidosis: insights from 123I serum amyloid P component scintigraphy in 484 patients

    OpenAIRE

    Lovat, L; Persey, M; Madhoo, S; Pepys, M; HAWKINS, P

    1998-01-01

    Background and aims—The liver is frequently involved in amyloidosis but the significance of hepatic amyloid has not been systematically studied. We have previously developed scintigraphy with 123I serum amyloid P component (123I-SAP) to identify and monitor amyloid deposits quantitatively in vivo and we report here our findings in hepatic amyloidosis. ?Methods—Between 1988 and 1995, 805 patients with clinically suspected or biopsy proven systemic amyloidosis were evaluate...

  11. Prediction of Peptide and Protein Propensity for Amyloid Formation.

    Science.gov (United States)

    Família, Carlos; Dennison, Sarah R; Quintas, Alexandre; Phoenix, David A

    2015-01-01

    Understanding which peptides and proteins have the potential to undergo amyloid formation and what driving forces are responsible for amyloid-like fiber formation and stabilization remains limited. This is mainly because proteins that can undergo structural changes, which lead to amyloid formation, are quite diverse and share no obvious sequence or structural homology, despite the structural similarity found in the fibrils. To address these issues, a novel approach based on recursive feature selection and feed-forward neural networks was undertaken to identify key features highly correlated with the self-assembly problem. This approach allowed the identification of seven physicochemical and biochemical properties of the amino acids highly associated with the self-assembly of peptides and proteins into amyloid-like fibrils (normalized frequency of ?-sheet, normalized frequency of ?-sheet from LG, weights for ?-sheet at the window position of 1, isoelectric point, atom-based hydrophobic moment, helix termination parameter at position j+1 and ?G° values for peptides extrapolated in 0 M urea). Moreover, these features enabled the development of a new predictor (available at http://cran.r-project.org/web/packages/appnn/index.html) capable of accurately and reliably predicting the amyloidogenic propensity from the polypeptide sequence alone with a prediction accuracy of 84.9 % against an external validation dataset of sequences with experimental in vitro, evidence of amyloid formation. PMID:26241652

  12. Prediction of Peptide and Protein Propensity for Amyloid Formation

    Science.gov (United States)

    Família, Carlos; Dennison, Sarah R.; Quintas, Alexandre; Phoenix, David A.

    2015-01-01

    Understanding which peptides and proteins have the potential to undergo amyloid formation and what driving forces are responsible for amyloid-like fiber formation and stabilization remains limited. This is mainly because proteins that can undergo structural changes, which lead to amyloid formation, are quite diverse and share no obvious sequence or structural homology, despite the structural similarity found in the fibrils. To address these issues, a novel approach based on recursive feature selection and feed-forward neural networks was undertaken to identify key features highly correlated with the self-assembly problem. This approach allowed the identification of seven physicochemical and biochemical properties of the amino acids highly associated with the self-assembly of peptides and proteins into amyloid-like fibrils (normalized frequency of ?-sheet, normalized frequency of ?-sheet from LG, weights for ?-sheet at the window position of 1, isoelectric point, atom-based hydrophobic moment, helix termination parameter at position j+1 and ?G° values for peptides extrapolated in 0 M urea). Moreover, these features enabled the development of a new predictor (available at http://cran.r-project.org/web/packages/appnn/index.html) capable of accurately and reliably predicting the amyloidogenic propensity from the polypeptide sequence alone with a prediction accuracy of 84.9 % against an external validation dataset of sequences with experimental in vitro, evidence of amyloid formation. PMID:26241652

  13. Anti-serum amyloid component P antibodies in patients with systemic lupus erythematosus correlate with disease activity

    OpenAIRE

    Zandman-Goddard, G; Blank, M.; LANGEVITZ, P.; Slutsky, L; Pras, M.; Levy, Y; Shovman, O.; Witte, T.; Doria, A.; Rovensky, J; Shoenfeld, Y

    2005-01-01

    Objective: To determine the presence of raised titres of anti-serum amyloid P component (SAP) antibodies in patients with systemic lupus erythematosus (SLE) and to evaluate their correlation with clinical disease by the SLEDAI and clinical manifestations.

  14. Genetic polymorphisms of serum amyloid A1 and coronary artery disease risk.

    Science.gov (United States)

    Xie, X; Ma, Y-T; Yang, Y-N; Li, X-M; Zheng, Y-Y; Liu, F; Ma, X; Fu, Z-Y; Yu, Z-X; Chen, Y; Chen, B-D; Huang, Y

    2015-03-01

    Serum amyloid A (SAA) protein is not only an inflammatory factor but also an apolipoprotein that can replace apolipoprotein A1 (apoA1) as the major apolipoprotein of high-density lipoprotein cholesterol (HDL-C). However, the relationship between genetic polymorphisms of SAA and coronary artery disease (CAD) remains unclear. A total of four single nucleotide polymorphisms (rs12218, rs4638289, rs7131332, and rs11603089) of the SAA gene were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in two independent case-control studies, one of the Han population (1416 CAD patients and 1373 control subjects) and the other of the Uygur population (588 CAD patients and 529 control subjects). We found that the rs12218 CC genotype was more frequent among the CAD patients than among the controls in both the Han (8.3% vs. 4.8%, P?Genetic polymorphisms in SAA1 are associated with CAD in the Han and Uygur populations in western China. PMID:25656165

  15. Characterization of serum amyloid A (SAA) in rainbow trout using a new monoclonal antibody

    DEFF Research Database (Denmark)

    Kania, Per Walter; Chettri, Jiwan Kumar

    2014-01-01

    Serum amyloid A (SAA) is an integral part of the innate immune response in mammals and considered to be important during the acute phase response. The present study was undertaken to elucidate the role of SAA protein in the innate immune response of rainbow trout. A monoclonal antibody raised against a recombinant peptide of rainbow trout SAA was characterized using Western blot, dot blot, ELISA and immunohistochemistry. SAA association with high density lipoprotein (HDL) complicated band identification in Western blot, but delipidization of the SAA-HDL isolate highly increased the quality of reaction in the western blot. Rainbow trout fry (87 days post hatch) infected with Yersinia ruckeri showed a significant up-regulation of the SAA gene at 72 h post infection with an increase until 96 h post infection. Non-significant up-regulations were seen at earlier time points i.e. 4 and 24 h. The expression pattern of SAA significantly correlated to the immunohistochemical analysis of the infected fry. A weak staining was seen in liver tissue at 4 h post infection which increased in intensity during the course of infection i.e. 24, 72 and 96 h post infection.

  16. Serum amyloid P ameliorates radiation-induced oral mucositis and fibrosis

    Directory of Open Access Journals (Sweden)

    Murray Lynne A

    2010-07-01

    Full Text Available Abstract Purpose To evaluate the effect of the anti-fibrotic protein serum amyloid P (SAP on radiation-induced oral mucositis (OM and fibrosis in a hamster cheek-pouch model. Experimental Design Hamsters received a single dose of radiation (40 Gy to the left everted cheek pouch to induce significant OM. The protective therapeutic potential of SAP was evaluated using varying dosing regimens. The extent of OM was measured using a validated six-point scoring scheme ranging from 0 (normal tissue, no mucositis to 5 (complete ulceration. Fibrotic remodeling was also visualized histologically and quantified at later time points using collagen gene expression. Results SAP treatment attenuated the profile of radiation-induced oral mucositis by delaying the time of onset, reducing the peak value, and enhancing the resolution of injury. The peak mucositis score was reduced by approximately 0.5 grade in SAP-treated animals. The number of animal days with a score of ? 3 was reduced by 48% in the SAP-treated group, compared with the saline control group (P Conclusions SAP treatment significantly attenuated radiation-induced injury. In particular, SAP attenuated the severity of OM and inhibited pathogenic remodeling. This suggests that SAP may be a useful therapy for the palliation of side effects observed during treatment for head and neck cancer.

  17. Predictive values of serum amyloid-A and CRP for infection in febrile neutropenic cancer patients

    Directory of Open Access Journals (Sweden)

    Ay?e Bat?rel

    2014-12-01

    Full Text Available Objectives: To evaluate predictive values of serum amyloid A (SAA and C-reactive protein (CRP for infection and mor­tality in patients with febrile neutropenia (FEN. Methods: Daily measurement of serum SAA and CRP levels of patients during antibiotherapy for FEN. Results: Sixty-five FEN episodes of 52 patients were evaluated. Median CRP and SAA levels on 1st day of FEN were 137 mg/L (23-420 mg/L and 547 mg/L (11-1660 mg/L, respectively. For detection of infection of infection the sensitivity, positive predictive value (PPV, and negative predictive value (NPV of SAA at a level of >80 mg/L were as 100%, 48% and 100%. Whilethe sensitivity, PPV, and NPV of CRP at a level of >50mg/L were as 86%, 47% and 60%, respectively. Predictive values of initial SAA and CRP levels for infection didn’t differ significantly (CRP: p=0.24, SAA: p=0.39. SAA and CRP levels on the last day of FEN course were significant for infection and mortality (for infection: p=0.003 for CRP and p=0.026 for SAA; for mortality: p<0.001 for CRP and p=0.021 for SAA. Both initial and daily SAA and CRP levels correlated with each other positively and statistically significantly (p<0.001. The area under the curve (AUC on the re­ceiver operating character (ROC curve for CRP and SAA were 0.72 (p=0.003, 95% CI: 0.59-0.86 and 0.68 (p=0.19, 95% CI: 0.54-0.82, respectively. Conclusions: Despite low predictive values in decision of initial therapy, these parameters would be helpful in decision of modification and evaluation of response to therapy. J Microbiol Infect Dis 2014; 4(4: 128-135

  18. Serum amyloid P component inhibits influenza A virus infections: in vitro and in vivo studies

    DEFF Research Database (Denmark)

    Horvath, A; Andersen, I; Junker, K; Lyck Fogh-Schultz, B; Holm Nielsen, E; Gizurarson, S; Andersen, Ove; Karman, J; Rajnavolgyi, E; Erdei, A; Svehag, SE

    2001-01-01

    Serum amyloid P component (SAP) binds in vitro Ca(2+)-dependently to several ligands including oligosaccharides with terminal mannose and galactose. We have earlier reported that SAP binds to human influenza A virus strains, inhibiting hemagglutinin (HA) activity and virus infectivity in vitro. These studies were extended to comprise five mouse-adapted influenza A strains, two swine influenza A strains, a mink influenza A virus, a ferret influenza A reassortant virus, a influenza B virus and a p...

  19. Serum amyloid A as a sensitive marker of disease activity in rheumatic diseases

    OpenAIRE

    Singh, N.K. (Nitin); Ankur Nandan Varshney; Rajendra Prasad Meena

    2014-01-01

    Inflammation is known to play a major role in rheumatologic disorders. Hence quantitating the degree of inflammation has become essential to tailor the treatment strategy, especially with the discovery of potent biologicals. CRP and ESR are the currently used predominant inflammatory markers for rheumatologic disorders, but they have several limitations. Various studies have highlighted the superiority of serum amyloid A over these markers in quantitating inflammatory and treatment responses....

  20. Accumulation and expression of serum amyloid P component in human atherosclerotic lesions

    OpenAIRE

    Song, Zhiqing; Cai, Lei; Guo, Ling; Tsukamoto, Yoshitane; Yutani, Chikao; Li, Xiang-An

    2010-01-01

    Serum amyloid P component (SAP) is a member of pentraxins. Previous studies indicate that SAP exists in human atherosclerotic aortic intima and the plasma SAP levels are associated with cardiovascular disease. In this study, we characterized SAP in normal and atherosclerotic intima, investigated the source of SAP in atherosclerotic lesions, and assessed the effect of SAP on HDL function. Immunohistochemical staining and electroimmunoassay indicated that SAP is not present in normal aortic int...

  1. Amyloid-binding proteins: affinity-based separation, proteomic identification, and optical biosensor validation.

    Science.gov (United States)

    Medvedev, Alexei; Buneeva, Olga; Kopylov, Arthur; Gnedenko, Oksana; Ivanov, Alexis; Zgoda, Victor; Makarov, Alexander A

    2015-01-01

    The amyloid-beta peptide is considered as a key player in the development and progression of Alzheimer's disease (AD). Although good evidence exists that amyloid-beta accumulates inside cells, intracellular brain amyloid-beta-binding proteins remain poorly characterized. Here we describe a protocol for affinity-based profiling of amyloid-beta-binding proteins of rat brain, their proteomic identification and validation by a surface plasmon resonance (SPR)-based analysis. It includes: (a) SPR-based selection of immobilization conditions for beta-amyloid coupling and choice of appropriate resin for preparation of an affinity sorbent; (b) immobilization of beta-amyloid on the selected resin; PMID:25820741

  2. Characterization of rat serum amyloid A4 (SAA4): A novel member of the SAA superfamily

    International Nuclear Information System (INIS)

    Highlights: • The full length rat SAA4 (rSAA4) mRNA was characterized by rapid amplification of cDNA ends. • rSAA4 mRNA has 1830 bases including a GA dinucleotide tandem repeat in the 5?UTR. • Three consecutive C/EBP promoter elements are crucial for transcription of rSAA4. • rSAA4 is abundantly expressed in the liver on mRNA and protein level. - Abstract: The serum amyloid A (SAA) family of proteins is encoded by multiple genes, which display allelic variation and a high degree of homology in mammals. The SAA1/2 genes code for non-glycosylated acute-phase SAA1/2 proteins, that may increase up to 1000-fold during inflammation. The SAA4 gene, well characterized in humans (hSAA4) and mice (mSaa4) codes for a SAA4 protein that is glycosylated only in humans. We here report on a previously uncharacterized SAA4 gene (rSAA4) and its product in Rattus norvegicus, the only mammalian species known not to express acute-phase SAA. The exon/intron organization of rSAA4 is similar to that reported for hSAA4 and mSaa4. By performing 5?- and 3?RACE, we identified a 1830-bases containing rSAA4 mRNA (including a GA-dinucleotide tandem repeat). Highest rSAA4 mRNA expression was detected in rat liver. In McA-RH7777 rat hepatoma cells, rSAA4 transcription was significantly upregulated in response to LPS and IL-6 while IL-1?/? and TNF? were without effect. Luciferase assays with promoter-truncation constructs identified three proximal C/EBP-elements that mediate expression of rSAA4 in McA-RH7777 cells. In line with sequence prediction a 14-kDa non-glycosylated SAA4 protein is abundantly expressed in rat liver. Fluorescence microscopy revealed predominant localization of rSAA4-GFP-tagged fusion protein in the ER

  3. Identification of tetranectin as adipogenic serum protein.

    Science.gov (United States)

    Park, Jihyun; Park, Jeongho; Jeong, Jinju; Cho, Kyung-Hyun; Choi, Inho; Kim, Jihoe

    2015-05-01

    Fetal bovine serum (FBS) is an essential culture supplement for adipocyte differentiation of various adipogenic precursor cells. Adipocyte differentiation greatly varies depending on the type of serum in the differentiation medium. In this study, we found that FBS supported adipocyte differentiation of 3T3-L1 cells to a significantly higher extent than other types of bovine serum such as adult bovine serum (ABS). This differential adipogenic effect of bovine serum was shown to be due to the protein contents of bovine sera, indicating the presence of an adipogenic protein(s) in FBS. Serum proteome analysis identified tetranectin as an adipogenic protein. The adipogenic effect of tetranectin was confirmed by supplementation of FBS-containing differentiation medium with anti-tetranectin antibody, which suppressed adipocyte differentiation of 3T3-L1 cells. These results demonstrate that tetranectin is an adipogenic serum protein mediating the adipogenic effect of FBS. PMID:25797624

  4. Administration of perioperative penicillin reduces postoperative serum amyloid A response in horses being castrated standing

    DEFF Research Database (Denmark)

    Busk, Peter; Jacobsen, Stine

    2010-01-01

    Objectives: To compare postoperative in?ammatory responses in horses administered perioperative procaine penicillin and those not administered penicillin using acute phase protein serum amyloid A (SAA) as a marker of in?ammation. Study Design: Randomized clinical trial. Animals: Stallions (n = 50) castrated under ?eld conditions. Methods: SAA concentrations were determined on days 0, 3, and 8. Six horses were subsequently excluded because of elevated SAA concentrations on day 0. Of the remaining 50 horses, 26 were administered nonsteroidal anti-in?ammatory drug (NSAID) therapy and 24 were administered NSAID and 25,000 U/kg procaine penicillin on day 0, 1, and 2. Results: SAA concentrations increased signi?cantly from preoperative levels in both groups, and on day 8 concentrations were signi?cantly (P o .02) higher in horses administered only NSAID than in those administered procaine penicillin and NSAID. Infectious complications occurred more frequently (P o .01) in horses with preoperatively elevated SAA concentrations (the excluded horses) than in horses with normal preoperative SAA concentrations (the included horses). Conclusions: Perioperative antimicrobial therapy reduced the postoperative SAA response, suggesting that bacteria were present in the surgical wound and contributed to in?ammation after castration. Horses with elevated preoperative SAA concentrations developed infectious complications more often than horses with normal preoperative SAA concentrations. Clinical Relevance: Administration of antimicrobials may be important in horses being castrated standing under ?eld conditions. Increased SAA concentrations seem to be an indicator of increased surgical risk in horses and may be useful before elective surgery for planning.

  5. The zipper groups of the amyloid state of proteins

    Energy Technology Data Exchange (ETDEWEB)

    Stroud, James C., E-mail: jstroud@mbi.ucla.edu [University of California at Los Angeles, Box 951570, Los Angeles, CA 90095-1570 (United States)

    2013-04-01

    A formal derivation is provided of the 15 symmetry groups (zipper groups) available to the amyloid homosteric zipper. Fibrous proteins in the amyloid state are found both associated with numerous diseases and in the normal functions of cells. Amyloid fibers contain a repetitive spine, commonly built from a pair of ?-sheets whose ?-strands run perpendicular to the fiber direction and whose side chains interdigitate, much like the teeth of a zipper. In fiber spines known as homosteric zippers, identical protein segments sharing identical packing environments make the two ?-sheets. In previous work based on atomic resolution crystal structures of homosteric zippers derived from a dozen proteins, the symmetries of homosteric zippers were categorized into eight classes. Here, it is shown through a formal derivation that each homosteric zipper class corresponds to a unique set of symmetry groups termed ‘zipper groups’. Furthermore, the eight previously identified classes do not account for all of the 15 possible zipper groups, which may be categorized into the complete set of ten classes. Because of their foundations in group theory, the 15 zipper groups provide a mathematically rigorous classification for homosteric zippers.

  6. Modulation of fibrin clot formation by human serum amyloid P component (SAP) and heparin

    OpenAIRE

    1983-01-01

    Serum amyloid P-component (SAP) is a normal plasma constituent in man with a circulating concentration of approximately 40 micrograms/ml. Supraphysiological amounts of SAP (150-300 micrograms/ml) have been reported to affect coagulation. We have investigated this further by studying the effect of SAP upon clot times in both the absence and presence of heparin, a suggested ligand for SAP and itself a modulator of coagulation processes. In the absence of heparin, SAP (5-125 micrograms/ml) had n...

  7. Investigation of the solubility and the potentials for purification of serum amyloid A (SAA) from equine acute phase serum : a pilot study

    DEFF Research Database (Denmark)

    Christensen, Michelle BrØnniche; SØrensen, Jens Christian

    2013-01-01

    BACKGROUND: Serum amyloid A (SAA) is useful as a diagnostic marker of systemic inflammation in horses, but only heterologous assays based on non-equine calibration and standardization are available for measurements of equine SAA. More accurate measurements could be obtained using purified species-specific SAA in native conformation for assay calibration and standardization. Further knowledge about the biochemical properties of SAA would facilitate a future production of native species-specific calibration material Therefore, the aim of the study was an investigation of the solubility and potentials for purification of equine SAA based on biochemical properties.Freeze dried equine acute phase serum was dissolved in 70% 2-propanol, 8 M urea, and milli-Q water, respectively. Supercritical fluid extraction (SFE), size-exclusive chromatography (FPLC-SEC), and preparative isoelectric focusing (IEF) were performed in the attempt to purify. Immunostaining of IEF blots were used for isoform-specific detection of SAA in the preparations and purity was assessed by silverstained SDS-PAGE. FINDINGS: SAA was soluble in 70% 2-propanol, 8 M urea and Milli-Q water. SAA was not separated in the lipophilic or ampipathic fractions following SFE. SAA was included in a FPLC-SEC-fraction of 237 kDa, despite the molecular weight known to be much smaller, suggesting binding to other serum constituents. SAA precipitated following separation of other serum proteins by preparative IEF. DISCUSSION: No effective purification of SAA was achieved in the present study, but findings important for future investigations were made. The study suggested that SAA is not exclusively hydrophobic, but appears less hydrophobic when interacting with other serum components. These results suggest more complex aspects of solubility than previously believed, and indicate potentials for purification of native SAA.

  8. Protein Polymers and Amyloids : Focus on ?1-Antitrypsin

    DEFF Research Database (Denmark)

    RisØr, Michael Wulff

    2014-01-01

    Several human disorders are caused by a common general disease mechanism arising from abnormal folding and aggregation of the underlying protein. These include the prevalent dementias like Alzheimer’s and Parkinson’s, where accumulation of protein fibrillar structures, known as amyloid fibrils, is a general hallmark. They also include the ?1-antitrypsin deficiency, where disease-causing mutations in the serine protease inhibitor, ?1-antitrypsin (?1AT), leads to accumulation of the aberrant protein in the liver of these patients. The native metastable structure of ?1AT constitutes a molecular trap that inhibits its target protease through a large conformational change but mutations compromise this function and cause premature structural collapse into hyperstable polymers. Understanding the conformational disorders at a molecular level is not only important for our general knowledge on protein folding and misfolding but also for rationalizing efficient therapeutic strategies to ameliorate the associated disease. In this work, we focussed on the C-terminal part of ?1AT to understand its role in the disease-causing polymerization events and to investigate the amyloid fibril formation of a proteolytically generated fragment from here. To enable a detailed structural analysis by Nuclear Magnetic Resonance Spectroscopy an in vitro ligation procedure was established that reconstituted ?1AT from two separate fragments. In this way, it would be possible to incorporate NMR-active isotopes in the C-terminal part selectively. Extensive biochemical work established successful expressed protein ligation for two separate ligation joints in ?1AT and provided proof-of-concept for the strategy. The polymerization of ?1AT can happen trough the insertion of the C-terminal tail into the succeeding molecule and features of this mechanism were investigated through a series of interaction experiments. Despite a very buried location in the native structure, evidence here suggest that the C-terminal tail is labile under slightly destabilizing conditions, providing new detail to this matter. A small infectious polymer unit was also constructed and used to show how polymerogenic seeding and polymer propagation might happen inside the body. The locking of central structural elements during ?1AT folding or in the native state represents a therapeutic strategy to prevent polymerization. Using Molecular Dynamics simulations, we identified a new druggable pocket on the surface of ?1AT that could be targeted to serve this purpose. The proteolytically generated C-terminal tail from ?1AT is 36 residues long (C- 36) and is present in various bodily fluids. The peptide is able to form amyloid fibrils and we provide the first characterization of the fibrillation mechanism and of the amyloid structures that arise. The fibrillation is greatly enhanced by the presence of the anionic heparin sugar chain and we establish a model to describe these effects. Such negatively charged sugar molecules are ubiquitously associated with amyloid deposits in vivo, underlining the importance of understanding this relationship. The monomeric C-36 peptide was investigated by liquid-state NMR spectroscopy and found to be intrinsically disordered with minor propensities towards ?-sheet structure. The plasticity of such a peptide makes it suitable for a whole range of interactions, including its conversion to the tightly packed repetitive ?-sheet arrangement of an amyloid fibre. The ultra-structural details of these fibres were established by electron microscopy and solid-state NMR was employed to resolve the underlying molecular structure. This last task has not been completed yet but solving such structures to atomic resolution is of high value for understanding and targeting the culprits of the amyloid-related conformational disorders. Lastly, this work also includes a study on the protease HtrA1 that localizes to certain amyloid plaques. We explore the mechanism behind its automaturation process and find it to depend on the integrity of a disulphide bond network

  9. Serum protein capillary electrophoresis and measurement of acute phase proteins in a captive cheetah (Acinonyx jubatus) population

    DEFF Research Database (Denmark)

    Depauw, Sarah; Delanghe, Joris

    2014-01-01

    Renal and gastrointestinal pathologies are widespread in the captive cheetah (Acinonyx jubatus) population but are often diagnosed at a late stage, because diagnostic tools are limited to the evaluation of clinical signs or general blood examination. Presently, no data are available on serum proteins and acute-phase proteins in cheetahs during health or disease, although they might be important to improve health monitoring. This study aimed to quantify serum proteins by capillary electrophoresis in 80 serum samples from captive cheetahs, categorized according to health status and disease type. Moreover, serum amyloid A concentrations were measured via a turbidimetric immunoassay validated in domestic cats, whereas haptoglobin and C-reactive protein were determined by non-species-specific functional tests. Cheetahs classified as healthy had serum protein and acute phase protein concentrations within reference ranges for healthy domestic cats. In contrast, unhealthy cheetahs had higher (P < 0.001) serum amyloidA, alpha2-globulin, and haptoglobin concentrations compared with the healthy subgroup. Moreover, serum amyloid A (P = 0.020), alpha2-globulin (P < 0.001) and haptoglobin (P = 0.001) concentrations in cheetahs suffering from chronic kidney disease were significantly greater compared to the reportedly healthy cheetahs. Our study indicates that serum proteins in the cheetah can be analyzed by routine capillary electrophoresis, whereas acute-phase proteins can be measured using available immunoassays or non-species-specific techniques, which are also likely to be applicable in other exotic felids. Moreover, results suggest that serum amyloid A and haptoglobin are important acute-phase proteins in the diseased cheetah and highlight the need to evaluate their role as early-onset markers for disease.

  10. Protein microgels from amyloid fibril networks.

    Science.gov (United States)

    Shimanovich, Ulyana; Efimov, Igor; Mason, Thomas O; Flagmeier, Patrick; Buell, Alexander K; Gedanken, Aharon; Linse, Sara; Åkerfeldt, Karin S; Dobson, Christopher M; Weitz, David A; Knowles, Tuomas P J

    2015-01-27

    Nanofibrillar forms of proteins were initially recognized in the context of pathology, but more recently have been discovered in a range of functional roles in nature, including as active catalytic scaffolds and bacterial coatings. Here we show that protein nanofibrils can be used to form the basis of monodisperse microgels and gel shells composed of naturally occurring proteins. We explore the potential of these protein microgels to act as drug carrier agents, and demonstrate the controlled release of four different encapsulated drug-like small molecules, as well as the component proteins themselves. Furthermore, we show that protein nanofibril self-assembly can continue after the initial formation of the microgel particles, and that this process results in active materials with network densities that can be modulated in situ. We demonstrate that these materials are nontoxic to human cells and that they can be used to enhance the efficacy of antibiotics relative to delivery in homogeneous solution. Because of the biocompatibility and biodegradability of natural proteins used in the fabrication of the microgels, as well as their ability to control the release of small molecules and biopolymers, protein nanofibril microgels represent a promising class of functional artificial multiscale materials generated from natural building blocks. PMID:25469621

  11. Amyloid Precursor Protein Binding Protein-1 Is Up-regulated in Brains of Tg2576 Mice

    OpenAIRE

    Yang, Hyun Jung; Joo, Yuyoung; Hong, Bo-Hyun; Ha, Sung-Ji; Woo, Ran-Sook; Lee, Sang Hyung; Suh, Yoo-hun; Kim, Hye-Sun

    2010-01-01

    Amyloid precursor protein binding protein-1 (APP-BP1) binds to the carboxyl terminus of amyloid precursor protein and serves as a bipartite activation enzyme for the ubiquitin-like protein, NEDD8. Previously, it has been reported that APP-BP1 rescues the cell cycle S-M checkpoint defect in Ts41 hamster cells, that this rescue is dependent on the interaction of APP-BP1 with hUba3. The exogenous expression of APP-BP1 in neurons has been reported to cause DNA synthesis and apoptosis via a signal...

  12. Validación analítica de técnicas comerciales para la determinación de haptoglobina, proteína C reactiva y amiloide A sérico en caninos Analytical / validation of commercial assays for the determination of haptoglobin, C-reactive protein and serum amyloid A in dogs

    Scientific Electronic Library Online (English)

    S., Martínez-Subiela; J. J., Cerón.

    Full Text Available Los métodos analíticos deben ser validados antes de emplearlos de forma rutinaria en un laboratorio. El objetivo de este trabajo fue validar tres métodos analíticos comerciales usados en nuestro laboratorio para la determinación de haptoglobina (Hp), proteína C reactiva (CRP) y amiloide A sérico (SA [...] A) en muestras de la especie canina con concentraciones bajas y altas de proteínas de fase aguda (PFAs). Los parámetros que se evaluaron para la validación fueron: (1) Precisión, determinada mediante el cálculo de los coeficientes de variación (CVs) intra e interdeterminación. (2) Exactitud, evaluada indirectamente comprobando la linealidad bajo dilución. (3) Límite de detección, determinado como la mínima concentración que puede distinguirse de una muestra de valor 0. Todos los CVs intradeterminación fueron Abstract in english All laboratory tests must be validated before being introduced for patient testing. The objective of this work was to perform the analytical validation of three commercial assays that are being used at our laboratory for the determination of haptoglobin (Hp), C reactive protein (CRP) and serum amylo [...] id A (SAA) in canine samples with low and high concentrations of these acute phase proteins (APPs). The parameters evaluated for the validation of the methods were: (1) Precision, assessed by determination of the within and between-run coefficients of variation (CVs). (2) Inaccuracy, evaluated indirectly by investigating linearity under dilution. (3) Limit of detection, determined as the lowest concentration of the APPs which could be distinguished from a zero sample. All within-run CVs were lower than 10%, however between-run CVs were lower than 10% only for Hp. Dilution of a serum sample with high concentrations of the different APPs resulted in a linear regression equation with correlation coefficient R²0.98 in all cases; so all methods showed a good accuracy. The detection limit of each assay was 0.02 g/L for Hp, 0.15 mg/L for CRP and 0.79 mg/L for SAA. Additionally they differentiate animals with inflammatory or infectious diseases from healthy subjects. Overall results of validation showed that the assays tested can be suitable for the routine measurement of APPs in canine samples, although it would be desirable to reduce the between run imprecision found for CRP and SAA assays.

  13. Distinctive serum protein profiles involving abundant proteins in lung cancer patients based upon antibody microarray analysis

    International Nuclear Information System (INIS)

    Cancer serum protein profiling by mass spectrometry has uncovered mass profiles that are potentially diagnostic for several common types of cancer. However, direct mass spectrometric profiling has a limited dynamic range and difficulties in providing the identification of the distinctive proteins. We hypothesized that distinctive profiles may result from the differential expression of relatively abundant serum proteins associated with the host response. Eighty-four antibodies, targeting a wide range of serum proteins, were spotted onto nitrocellulose-coated microscope slides. The abundances of the corresponding proteins were measured in 80 serum samples, from 24 newly diagnosed subjects with lung cancer, 24 healthy controls, and 32 subjects with chronic obstructive pulmonary disease (COPD). Two-color rolling-circle amplification was used to measure protein abundance. Seven of the 84 antibodies gave a significant difference (p < 0.01) for the lung cancer patients as compared to healthy controls, as well as compared to COPD patients. Proteins that exhibited higher abundances in the lung cancer samples relative to the control samples included C-reactive protein (CRP; a 13.3 fold increase), serum amyloid A (SAA; a 2.0 fold increase), mucin 1 and ?-1-antitrypsin (1.4 fold increases). The increased expression levels of CRP and SAA were validated by Western blot analysis. Leave-one-out cross-validation was used to construct Diagonal Linear Discriminant Analysis (DLDA) classifiers. At a cutoff where all 56 of the non-tumor samples were correctly classified, 15/24 lung tumor patient sera were correctly classified. Our results suggest that a distinctive serum protein profile involving abundant proteins may be observed in lung cancer patients relative to healthy subjects or patients with chronic disease and may have utility as part of strategies for detecting lung cancer

  14. Evaluation of Infective Property of Recombinant Prion Protein Amyloids in Cultured Cells Overexpressing Cellular Prion Protein

    OpenAIRE

    Kim, Dae-Hwan; Lee, Hye-Mi; Ryou, Chongsuk

    2014-01-01

    Misfolded isoform of prion protein (PrP), termed scrapie PrP (PrPSc), tends to aggregate into various fibril forms. Previously, we reported various conditions that affect aggregation of recombinant PrP into amyloids. Because amyloidogenesis of PrP is closely associated with transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease in humans, we investigated infectivity of recombinant PrP amyloids generated in vitro. Using cultured cell lines which overexpress cellular PrP of...

  15. Serum Protein Profile Alterations in Hemodialysis Patients

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, G A; Davies, R W; Choi, M W; Perkins, J; Turteltaub, K W; McCutchen-Maloney, S L; Langlois, R G; Curzi, M P; Trebes, J E; Fitch, J P; Dalmasso, E A; Colston, B W; Ying, Y; Chromy, B A

    2003-11-18

    Background: Serum protein profiling patterns can reflect the pathological state of a patient and therefore may be useful for clinical diagnostics. Here, we present results from a pilot study of proteomic expression patterns in hemodialysis patients designed to evaluate the range of serum proteomic alterations in this population. Methods: Surface-Enhanced Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOFMS) was used to analyze serum obtained from patients on periodic hemodialysis treatment and healthy controls. Serum samples from patients and controls were first fractionated into six eluants on a strong anion exchange column, followed by application to four array chemistries representing cation exchange, anion exchange, metal affinity and hydrophobic surfaces. A total of 144 SELDI-TOF-MS spectra were obtained from each serum sample. Results: The overall profiles of the patient and control samples were consistent and reproducible. However, 30 well-defined protein differences were observed; 15 proteins were elevated and 15 were decreased in patients compared to controls. Serum from one patient exhibited novel protein peaks suggesting possible additional changes due to a secondary disease process. Conclusion: SELDI-TOF-MS demonstrated dramatic serum protein profile differences between patients and controls. Similarity in protein profiles among dialysis patients suggests that patient physiological responses to end-stage renal disease and/or dialysis therapy have a major effect on serum protein profiles.

  16. Serum amyloid-beta levels are increased in patients with obstructive sleep apnea syndrome

    Science.gov (United States)

    Bu, Xian-Le; Liu, Yu-Hui; Wang, Qing-Hua; Jiao, Shu-Sheng; Zeng, Fan; Yao, Xiu-Qing; Gao, Dong; Chen, Ji-Chuan; Wang, Yan-Jiang

    2015-01-01

    A critical link between amyloid-beta (A?) and hypoxia has been demonstrated in in vitro and animal studies but has not yet been proven in humans. Obstructive sleep apnea syndrome (OSAS) is a common disorder that is characterized by nocturnal intermittent hypoxaemia. This study sought to examine the association between the chronic intermittent hypoxia and A? in OSAS patients. Forty-five cognitively normal OSAS patients and forty-nine age- and gender-matched subjects diagnosed with simple snoring and not OSAS were included in the present study. Serum A?40, A?42, total tau and phosphorylated tau 181 (P-tau 181) levels were measured using ELISA kits. All subjects were evaluated with nighttime polysomnography and cognitive tests. Compared with the controls, the OSAS patients exhibited significantly higher serum A?40, A?42 and total A? levels, and each of these levels was positively correlated with the apnea-hypopnea index, the oxygen desaturation index, and the mean and lowest oxyhaemoglobin saturations in the OSAS patients. Moreover, the OSAS patients exhibited strikingly higher serum P-tau 181 levels, and these levels were positively correlated with serum A? levels. This study suggests that there is an association between chronic intermittent hypoxia and increased A? levels, implying that hypoxia may contribute to the pathogenesis of Alzheimer’s disease. PMID:26351108

  17. A Drosophila gene encoding a protein resembling the human ?-amyloid protein precursor

    International Nuclear Information System (INIS)

    The authors have isolated genomic and cDNA clones for a Drosophila gene resembling the human ?-amyloid precursor protein (APP). This gene produces a nervous system-enriched 6.5-kilobase transcript. Sequencing of cDNAs derived from the 6.5-kilobase transcript predicts an 886-amino acid polypeptide. This polypeptide contains a putative transmembrane domain and exhibits strong sequence similarity to cytoplasmic and extracellular regions of the human ?-amyloid precursor protein. There is a high probability that this Drosophila gene corresponds to the essential Drosophila locus vnd, a gene required for embryonic nervous system development

  18. Serum proteins analysis by capillary electrophoresis

    OpenAIRE

    Uji, Yoshinori; Okabe, Hiroaki

    2001-01-01

    The purpose of this study was to evaluate the efficacy of multi-capillary electrophoresis instrument in clinical laboratory. An automated clinical capillary electrophoresis system was evaluated for performing serum proteins electrophoresis and immuno-fixation electrophoresis by subtraction. In this study the performance of capillary electrophoresis was compared with the cellulose acetate membrane electrophoresis and agarose gel immunofixation electrophoresis for serum proteins. The results of...

  19. Structure of a Functional Amyloid Protein Subunit Computed Using Sequence Variation

    DEFF Research Database (Denmark)

    Tian, Pengfei; Boomsma, Wouter; Wang, Yong; Otzen, Daniel; Jensen, Mogens H; Lindorff-Larsen, Kresten

    2015-01-01

    Functional amyloid fibers, called curli, play a critical role in adhesion and invasion of many bacteria. Unlike pathological amyloids, curli structures are formed by polypeptide sequences whose amyloid structure has been selected for during evolution. This important distinction provides us with an opportunity to obtain structural insights from an unexpected source: the covariation of amino acids in sequences of different curli proteins. We used recently developed methods to extract amino acid co...

  20. Amyloid-clearing proteins and their epigenetic regulation as a therapeutic target in Alzheimer’s disease

    OpenAIRE

    Nalivaeva, Natalia N; Belyaev, Nikolai D.; Kerridge, Caroline; Turner, Anthony J.

    2014-01-01

    Abnormal elevation of amyloid ?-peptide (A?) levels in the brain is the primary trigger for neuronal cell death specific to Alzheimer’s disease (AD). It is now evident that A? levels in the brain are manipulable due to a dynamic equilibrium between its production from the amyloid precursor protein (APP) and removal by amyloid clearance proteins. Clearance can be either enzymic or non-enzymic (binding/transport proteins). Intriguingly several of the main amyloid-degrading enzymes (ADEs) are me...

  1. Human serum amyloid P component binds to a specific peptide in the presence of calcium.

    Science.gov (United States)

    Hamazaki, H

    1994-12-15

    Human serum amyloid P component (SAP) binds to a carboxyl-terminal peptide of residues 160-204 of SAP itself in the presence of calcium. A set of sequentially overlapping decapeptides covering the entire length of residues 160-204 of SAP was synthesized on polyethylene pins to be used for binding assay, and six overlapping peptides in residues 190-204 (Tyr-Glu-Ile-Arg-Gly-Tyr-Val-Ile-Ile-Lys-Pro-Leu-Val-Trp-Val) were found to have equally high affinity for SAP. The validity of using peptides on polyethylene pins was shown by the binding assay using 11-residue soluble peptide corresponding to residues 194-204. Replacement of the Lys or the Ile residues with Glu abolished the binding activity. PMID:7802647

  2. Acute phase serum amyloid A induces proinflammatory cytokines and mineralization via toll-like receptor 4 in mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Regina Ebert

    2015-07-01

    Full Text Available The role of serum amyloid A (SAA proteins, which are ligands for toll-like receptors, was analyzed in human bone marrow-derived mesenchymal stem cells (hMSCs and their osteogenic offspring with a focus on senescence, differentiation and mineralization. In vitro aged hMSC developed a senescence-associated secretory phenotype (SASP, resulting in enhanced SAA1/2, TLR2/4 and proinflammatory cytokine (IL6, IL8, IL1?, CXCL1, CXCL2 expression before entering replicative senescence. Recombinant human SAA1 (rhSAA1 induced SASP-related genes and proteins in MSC, which could be abolished by cotreatment with the TLR4-inhibitor CLI-095. The same pattern of SASP-resembling genes was stimulated upon induction of osteogenic differentiation, which is accompanied by autocrine SAA1/2 expression. In this context additional rhSAA1 enhanced the SASP-like phenotype, accelerated the proinflammatory phase of osteogenic differentiation and enhanced mineralization. Autocrine/paracrine and rhSAA1 via TLR4 stimulate a proinflammatory phenotype that is both part of the early phase of osteogenic differentiation and the development of senescence. This signaling cascade is tightly involved in bone formation and mineralization, but may also propagate pathological extraosseous calcification conditions such as calcifying inflammation and atherosclerosis.

  3. Serum amyloid a gene expression and immunohistochemical localization in rainbow trout, Oncorhynchus mykiss, infected by Yersinia ruckeri

    DEFF Research Database (Denmark)

    Kania, Per Walter; Buchmann, Kurt

    Serum amyloid A (SAA) is an integral part of the innate immune response in general and in particular the acute phase response. SAA belongs to a highly conserved group of apolipoproteins reported from different groups of organisms such as mammals, birds, fish and even invertebrates. The present study was undertaken to elucidate the role of SAA protein in the innate immune response of rainbow trout. For this purpose a monoclonal antibody was raised against a recombinant peptide of rainbow trout SAA. The antibody was characterized using Western blot, immunohistochemistry and ELISA techniques. SAA was found to be associated with high density lipoprotein (HDL) which complicated band identification in Western blot, but delipidization of the SAA-HDL isolate, using a solvent extraction method, highly increased the quality of reaction in the Western blot. Inhibition ELISA indicated the presence of SAA in serum and tissues (head kidney, liver and spleen) of rainbow trout. Rainbow trout fry (87 days post hatch) infected with Yersinia ruckeri showed a significant up-regulation of the SAA gene at 72 h post infection with further increase at 96 h post infection. Non-significant up-regulations were seen at earlier time points i.e. 4 and 24 h. A weak staining with the monoclonal antibody was seen at 4 h post infection which increased in intensity during the course of infection i.e. 24, 72 and 96 h post infection. The expression pattern of SAA in the infected fry, analysed by qPCR, significantly correlated with the results obtained by immunohistochemical methods. From the present study it can be concluded that the SAA may act as an acute phase protein in rainbow trout and its expression increases significantly during the course of infection.

  4. Amyloid fibril protein in familial amyloidotic polyneuropathy, Portuguese type. Definition of molecular abnormality in transthyretin (prealbumin).

    OpenAIRE

    Saraiva, M.J.; Birken, S; Costa, P.P.; Goodman, D. S.

    1984-01-01

    Amyloid fibril protein in patients with familial amyloidotic polyneuropathy is known to be chemically related to transthyretin (TTR), the plasma protein that is usually referred to as prealbumin. A genetically abnormal TTR may be involved in this disease. Studies were conducted on amyloid fibril protein (AFp) isolated from tissues of two Portuguese patients who died with familial amyloidosis, and on TTR isolated from sera of patients with this disease. AFp, purified by affinity chromatography...

  5. Curcumin Reduces Amyloid Fibrillation of Prion Protein and Decreases Reactive Oxidative Stress

    OpenAIRE

    Raymond Chung; Cheng-I Lee; Chi-Fen Lin; Cheng-Ping Jheng; Kun-Hua Yu

    2013-01-01

    Misfolding and aggregation into amyloids of the prion protein (PrP) is responsible for the development of fatal transmissible neurodegenerative diseases. Various studies on curcumin demonstrate promise for the prevention of Alzheimer’s disease and inhibition of PrPres accumulation. To evaluate the effect of curcumin on amyloid fibrillation of prion protein, we first investigated the effect of curcumin on mouse prion protein (mPrP) in a cell-free system. Curcumin reduced the prion fibril forma...

  6. Serum Amyloid-Beta Levels are Increased in Patients with Chronic Obstructive Pulmonary Disease.

    Science.gov (United States)

    Bu, Xian-Le; Cao, Guo-Qiang; Shen, Lin-Lin; Xiang, Yang; Jiao, Shu-Sheng; Liu, Yu-Hui; Zhu, Chi; Zeng, Fan; Wang, Qing-Hua; Wang, Ye-Ran; He, Yong; Zhou, Hua-Dong; Wang, Yan-Jiang

    2015-11-01

    Chronic obstructive pulmonary disease (COPD) is associated with cognitive decline, but the molecular link between COPD and dementia or Alzheimer's disease (AD) remains unclear. This study was aimed to investigate whether serum A? levels are correlated with COPD. 77 cognitively normal COPD patients and 45 age- and gender-matched normal controls were admitted to the study. Serum A?40 and A?42 levels were measured using ELISA kits. Serum C-reactive protein (CRP), interleukin 6 (IL-6), and procalcitonin (PCT) measurements were done using standard laboratory methods. Pulmonary function tests were performed to assess the pulmonary function and determine the degree of lung damage. Significantly increased levels of serum A?40, A?42, and total A? levels were found in patients with COPD in comparison with normal controls. In COPD patients, serum A? levels were higher in subjects with serum CRP, IL-6, and PCT upper the limit of normal. Moreover, serum A? levels were dramatically higher in COPD patients with worse pulmonary function. Our study suggests that cognitively normal COPD patients may undergo AD-related pathological changes, and COPD might facilitate AD-type pathogenesis. PMID:26243505

  7. Adenosine triphosphate (ATP) reduces amyloid-? protein misfolding in vitro.

    Science.gov (United States)

    Coskuner, Orkid; Murray, Ian V J

    2014-01-01

    Alzheimer's disease (AD) is a devastating disease of aging that initiates decades prior to clinical manifestation and represents an impending epidemic. Two early features of AD are metabolic dysfunction and changes in amyloid-? protein (A?) levels. Since levels of ATP decrease over the course of the disease and A? is an early biomarker of AD, we sought to uncover novel linkages between the two. First and remarkably, a GxxxG motif is common between both A? (oligomerization motif) and nucleotide binding proteins (Rossmann fold). Second, ATP was demonstrated to protect against A? mediated cytotoxicity. Last, there is structural similarity between ATP and amyloid binding/inhibitory compounds such as ThioT, melatonin, and indoles. Thus, we investigated whether ATP alters misfolding of the pathologically relevant A?42. To test this hypothesis, we performed computational and biochemical studies. Our computational studies demonstrate that ATP interacts strongly with Tyr10 and Ser26 of A? fibrils in solution. Experimentally, both ATP and ADP reduced A? misfolding at physiological intracellular concentrations, with thresholds at ~500 ?M and 1 mM respectively. This inhibition of A? misfolding is specific; requiring Tyr10 of A? and is enhanced by magnesium. Last, cerebrospinal fluid ATP levels are in the nanomolar range and decreased with AD pathology. This initial and novel finding regarding the ATP interaction with A? and reduction of A? misfolding has potential significance to the AD field. It provides an underlying mechanism for published links between metabolic dysfunction and AD. It also suggests a potential role of ATP in AD pathology, as the occurrence of misfolded extracellular A? mirrors lowered extracellular ATP levels. Last, the findings suggest that A? conformation change may be a sensor of metabolic dysfunction. PMID:24625803

  8. Magnesium modulates amyloid-beta protein precursor trafficking and processing.

    Science.gov (United States)

    Yu, Jia; Sun, Miao; Chen, Zheng; Lu, Jiangyang; Liu, Yi; Zhou, Liang; Xu, Xuemin; Fan, Dongsheng; Chui, Dehua

    2010-01-01

    Alzheimer's disease (AD), the most common form of dementia, is characterized by the presence of excessive deposits of aggregated amyloid-beta (Abeta), which is derived from the amyloid-beta protein precursor (AbetaPP) following processing by beta- and gamma-secretase. Metal elements are implicated in the pathophysiology of AD. Magnesium affects many biochemical mechanisms vital for neuronal properties and synaptic plasticity, and magnesium levels were reported to be decreased in various tissues including brain of AD patients. However, the exact role of magnesium in the neurodegenerative process of AD remains elusive. In this study, we investigated the effects of physiological (0.8 mM, as normal control), low (0-0.4 mM), and high (1.2-4.0 mM) concentrations of extracellular magnesium ([Mg2+]o) on AbetaPP processing and Abeta secretion. Here we show the effects of varying [Mg2+]o on AbetaPP processing is time- and dose-dependent. After 24 h treatment, high [Mg2+]o increased C-terminal fragment-alpha (CTFalpha) levels and soluble alpha-secretase cleaved AbetaPP (sAbetaPPalpha) release via enhancing retention of AbetaPP on plasma membrane. In contrast, low [Mg2+]o enhanced CTFbeta accumulation and Abeta secretion, and reduced cell surface AbetaPP level. Varying [Mg2+]o did not alter protein contents of full length AbetaPP. However, decreased total intracellular magnesium level by magnesium deprivation over 24 hr impaired cell viability. Normal AbetaPP processing could be restored when magnesium was adjusted back to physiological concentration. These data demonstrate that AbetaPP processing can be modulated by magnesium and at high [Mg2+]o, AbetaPP processing favors the alpha-secretase cleavage pathway. Our findings suggest that supplementation of magnesium has a therapeutic potential for preventing AD. PMID:20413885

  9. Assessement of serum amyloid A levels in the rehabilitation setting in the Florida manatee (Trichechus manatus latirostris).

    Science.gov (United States)

    Cray, Carolyn; Dickey, Meranda; Brewer, Leah Brinson; Arheart, Kristopher L

    2013-12-01

    The acute phase protein serum amyloid A (SAA) has been previously shown to have value as a biomarker of inflammation and infection in many species, including manatees (Trichechus manatus latirostris). In the current study, results from an automated assay for SAA were used in a rehabilitation setting. Reference intervals were established from clinically normal manatees using the robust method: 0-46 mg/L. More than 30-fold higher mean SAA levels were observed in manatees suffering from cold stress and boat-related trauma. Poor correlations were observed between SAA and total white blood count, percentage of neutrophils, albumin, and albumin/globulin ratio. A moderate correlation was observed between SAA and the presence of nucleated red blood cells. The sensitivity of SAA testing was 93% and the specificity was 98%, representing the highest combined values of all the analytes. The results indicate that the automated method for SAA quantitation can provide important clinical data for manatees in a rehabilitation setting. PMID:24450049

  10. Autoinhibition of Mint1 adaptor protein regulates amyloid precursor protein binding and processing

    OpenAIRE

    Matos, Maria F.; Xu, Yibin; Dulubova, Irina; Otwinowski, Zbyszek; John M. Richardson; Diana R Tomchick; Rizo, Josep; Ho, Angela

    2012-01-01

    Mint adaptor proteins bind to the amyloid precursor protein (APP) and regulate APP processing associated with Alzheimer’s disease; however, the molecular mechanisms underlying Mint regulation in APP binding and processing remain unclear. Biochemical, biophysical, and cellular experiments now show that the Mint1 phosphotyrosine binding (PTB) domain that binds to APP is intramolecularly inhibited by the adjacent C-terminal linker region. The crystal structure of a C-terminally extended Mint1 PT...

  11. Accumulation of cellular prion protein within dystrophic neurites of amyloid plaques in the Alzheimer's disease brain.

    Science.gov (United States)

    Takahashi, Reisuke H; Tobiume, Minoru; Sato, Yuko; Sata, Tetsutaro; Gouras, Gunnar K; Takahashi, Hidehiro

    2011-06-01

    Amyloid plaques, a well-known hallmark of Alzheimer's disease (AD), are formed by aggregated ?-amyloid (A?). The cellular prion protein (PrPc) accumulates concomitantly with A? in amyloid plaques. One type of amyloid plaque, classified as a neuritic plaque, is composed of an amyloid core and surrounding dystrophic neurites. PrPc immunoreactivity reminiscent of dystrophic neurites is observed in neuritic plaques. Proteinase K treatment prior to immunohistochemistry removes PrPc immunoreactivity from amyloid plaques, whereas A? immunoreactivity is enhanced by this treatment. In the present study, we used a chemical pretreatment by a sarkosyl solution (0.1% sarkosyl, 75 mM NaOH, 2% NaCl), instead of proteinase K treatment, to evaluate PrPc accumulation within amyloid plaques. Since PrPc within amyloid plaques is removed by this chemical pretreatment, we can recognize that the PrP species deposits within amyloid plaques were PrPc. We could observe that PrPc accumulation in dystrophic neurites occurred differently compared with A? or hyperphosphorylated tau aggregation in the AD brain. These results could support the hypothesis that PrPc accumulation in dystrophic neurites reflects a response to impairments in cellular degradation, endocytosis, or transport mechanisms associated with AD rather than a non-specific cross-reactivity between PrPc and aggregated A? or tau. PMID:21062360

  12. Serum Amyloid P Component Bound to Gram-Negative Bacteria Prevents Lipopolysaccharide-Mediated Classical Pathway Complement Activation

    OpenAIRE

    de Haas, Carla J.C.; van Leeuwen, Ester M.M.; van Bommel, Toon; Verhoef, Jan; van Kessel, Kok P.M.; van Strijp, Jos A.G.

    2000-01-01

    Although serum amyloid P component (SAP) is known to bind many ligands, its biological function is not yet clear. Recently, it was demonstrated that SAP binds to lipopolysaccharide (LPS). In the present study, SAP was shown to bind to gram-negative bacteria expressing short types of LPS or lipo-oligosaccharide (LOS), such as Salmonella enterica serovar Copenhagen Re and Escherichia coli J5, and also to clinical isolates of Haemophilus influenzae. It was hypothesized that SAP binds to the bact...

  13. Role of serum amyloid P component in bacterial infection: Protection of the host or protection of the pathogen

    OpenAIRE

    Noursadeghi, Mahdad; Bickerstaff, Maria C. M.; Gallimore, J. Ruth; Herbert, Jeff; Cohen, Jonathan; Pepys, Mark B.

    2000-01-01

    Serum amyloid P component (SAP) binds to Streptococcus pyogenes, and we show here that it also binds to Neisseria meningitidis, including a lipopolysaccharide (LPS)-negative mutant, and to rough variants of Escherichia coli. Surprisingly, this binding had a powerful antiopsonic effect both in vitro and in vivo, reducing phagocytosis and killing of bacteria. Furthermore, SAP knockout mice survived lethal infection with S. pyogenes and rough E. coli J5, organisms...

  14. Organization and Biology of the Porcine Serum Amyloid A (SAA) Gene Cluster: Isoform Specific Responses to Bacterial Infection.

    DEFF Research Database (Denmark)

    Olsen, Helle G; Skovgaard, Kerstin

    2013-01-01

    Serum amyloid A (SAA) is a prominent acute phase protein. Although its biological functions are debated, the wide species distribution of highly homologous SAA proteins and their uniform behavior in response to injury or inflammation in itself suggests a significant role for this protein. The pig is increasingly being used as a model for the study of inflammatory reactions, yet only little is known about how specific SAA genes are regulated in the pig during acute phase responses and other responses induced by pro-inflammatory host mediators. We designed SAA gene specific primers and quantified the gene expression of porcine SAA1, SAA2, SAA3, and SAA4 by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in liver, spleen, and lung tissue from pigs experimentally infected with the Gram-negative swine specific bacterium Actinobacillus pleuropneumoniae, as well as from pigs experimentally infected with the Gram-positive bacterium Staphylococcus aureus. Our results show that: 1) SAA1 may be a pseudogene in pigs; 2) we were able to detect two previously uncharacterized SAA transcripts, namely SAA2 and SAA4, of which the SAA2 transcript is primarily induced in the liver during acute infection and presumably contributes to circulating SAA in pigs; 3) Porcine SAA3 transcription is induced both hepatically and extrahepatically during acute infection, and may be correlated to local organ affection; 4) Hepatic transcription of SAA4 is markedly induced in pigs infected with A. pleuropneumoniae, but only weakly in pigs infected with S. aureus. These results for the first time establish the infection response patterns of the four porcine SAA genes which will be of importance for the use of the pig as a model for human inflammatory responses, e.g. within sepsis, cancer, and obesity research.

  15. B-Amyloid Precursor Protein Staining of the Brain in Sudden Infant and Early Childhood Death

    DEFF Research Database (Denmark)

    Jensen, Lisbeth Lund; Banner, Jytte

    2013-01-01

    To develop and validate a scoring method for assessing ?-amyloid precursor protein (APP) staining in cerebral white matter and to investigate the occurrence, amount and deposition pattern based on the cause of death in infants and young children.

  16. Protein ?-mediated effects on rat hippocampal choline transporters CHT1 and ?-amyloid ? interactions.

    Czech Academy of Sciences Publication Activity Database

    Krištofíková, Z.; ?ípová, D.; Hegnerová, Kate?ina; Šírová, J.; Homola, Ji?í

    2013-01-01

    Ro?. 38, ?. 9 (2013), s. 1949-1959. ISSN 0364-3190 Institutional support: RVO:67985882 Keywords : Tau protein * Amyloid ? peptide * Choline transporter Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 2.551, year: 2013

  17. Immunohistochemical identification and crossreactions of amyloid-A fibril protein in man and eleven other species.

    Science.gov (United States)

    Linke, R P; Hol, P R; Gruys, E; Geisel, O; Nathrath, W B; Trautwein, G

    1984-07-01

    Antisera were prepared in rabbits, sheep or chicken against purified amyloid fibril protein AA from man, mouse, stone marten, dog, cow and hamster. These antisera were tested by immunodiffusion against all purified antigens and applied to tissue sections containing amyloid from man, mouse, hamster, guinea pig, rabbit, cat, dog, mink, stone marten, pine marten, cow and horse. The binding of the antibodies to amyloid in tissue sections was assessed by the indirect immunoperoxidase method. The strongest reactions in the immunodiffusion and immunohistochemical methods were found between amyloid deposits of members of a given species and an antibody raised against protein AA from the same species. In contrast to the lack of cross-reactivity in immunodiffusion (except in the mouse-man relationship), extensive cross-reactions were observed immunohistochemically in phylogenetically related species, e.g. between stone marten, pine marten and mink, or between hamster and mouse. However, cross-reactions were also observed in combinations such as man-mouse, man-dog, man-cat, mouse-horse, and dog-cow. In addition, individual antisera showed variations in immunohistochemical reactivity with amyloid deposits of different members of one given species. Moreover, antisera prepared in rabbits reacted more restrictedly than those prepared in sheep, while rabbit antisera against any AA-protein did not react with rabbit amyloid. Finally, the widest degree of cross-reactivity including almost all mammalian species investigated was observed with a chicken antiserum to human amyloid AA protein. PMID:6432863

  18. Inhibiting transthyretin amyloid fibril formation via protein stabilization.

    OpenAIRE

    Miroy, G. J.; Lai, Z.; Lashuel, H. A.; Peterson, S. A.; Strang, C.; Kelly, J. W.

    1996-01-01

    Transthyretin (TTR) amyloid fibril formation is observed systemically in familial amyloid polyneuropathy and senile systemic amyloidosis and appears to be the causative agent in these diseases. Herein, we demonstrate conclusively that thyroxine (10.8 ?M) inhibits TTR fibril formation efficiently in vitro and does so by stabilizing the tetramer against dissociation and the subsequent conformational changes required for amyloid fibril formation. In addition, the nonn...

  19. Insights into the variability of nucleated amyloid polymerization by a minimalistic model of stochastic protein assembly

    CERN Document Server

    Eugene, Sarah; Robert, Philippe; Doumic-Jauffret, Marie

    2015-01-01

    Self-assembly of proteins into amyloid aggregates is an important biological phenomenon associated with human diseases such as Alzheimer's disease. Amyloid fibrils also have potential applications in nano-engineering of biomaterials. The kinetics of amyloid assembly show an exponential growth phase preceded by a lag phase, variable in duration as seen in bulk experiments and experiments that mimic the small volumes of cells. Here, to investigate the origins and the properties of the observed variability in the lag phase of amyloid assembly currently not accounted for by deterministic nucleation dependent mechanisms, we formulate a new stochastic minimal model that is capable of describing the characteristics of amyloid growth curves despite its simplicity. We then solve the stochastic differential equations of our model and give mathematical proof of a central limit theorem for the sample growth trajectories of the nucleated aggregation process. These results give an asymptotic description for our simple mode...

  20. A positive correlation between serum amyloid ? levels and depressive symptoms among community-dwelling elderly individuals in Japan

    Directory of Open Access Journals (Sweden)

    Tsuruga K

    2014-08-01

    Full Text Available Koji Tsuruga,1 Norio Sugawara,1 Norio Yasui-Furukori,1 Ippei Takahashi,2 Shoko Tsuchimine,1 Ayako Kaneda,1 Shigeyuki Nakaji,2 Kazuhiko Nakamura1 1Department of Neuropsychiatry, 2Department of Social Medicine, Hirosaki University School of Medicine, Hirosaki, Japan Background: Amyloid beta (A? levels have been associated with an increased risk of Alzheimer’s disease (AD. As depression is common before the onset of AD, serum Aß levels could be associated with depressive symptoms. The aim of this study was to investigate whether serum A? levels are associated with depressive symptoms and/or cognitive function in community-dwelling elderly individuals. Methods: We examined the association between serum A? levels and depression among 419 Japanese community-dwelling elderly individuals aged 60 years and over. Subjects were divided into two subgroups: younger elderly between 60 and 69 years old and older elderly over 69 years old. The Mini-Mental State Examination (MMSE was used to assess cognitive function, and symptoms of depression were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D. The ability to perform activities of daily living was evaluated using the Tokyo Metropolitan Institute of Gerontology Index of Competence. Serum A? levels were measured with a human amyloid beta enzyme-linked immunosorbent assay kit. Results: After controlling for potential confounding variables, a multiple linear regression analysis showed that increased levels of serum A?40 and A?42 were associated with higher CES-D scores in the older elderly subgroup. Under the same condition, multiple regression showed that serum A? levels were not associated with MMSE scores among the total subjects, younger elderly, or older elderly. Conclusion: Serum A? levels were associated with depressive symptoms in community-dwelling elderly individuals. The present study indicates the possibility that serum A? may be involved in the development of late-onset depression. Keywords: Alzheimer’s disease, depression, dementia, Japanese

  1. Protein Folding and Aggregation into Amyloid: The Interference by Natural Phenolic Compounds

    Directory of Open Access Journals (Sweden)

    Massimo Stefani

    2013-06-01

    Full Text Available Amyloid aggregation is a hallmark of several degenerative diseases affecting the brain or peripheral tissues, whose intermediates (oligomers, protofibrils and final mature fibrils display different toxicity. Consequently, compounds counteracting amyloid aggregation have been investigated for their ability (i to stabilize toxic amyloid precursors; (ii to prevent the growth of toxic oligomers or speed that of fibrils; (iii to inhibit fibril growth and deposition; (iv to disassemble preformed fibrils; and (v to favor amyloid clearance. Natural phenols, a wide panel of plant molecules, are one of the most actively investigated categories of potential amyloid inhibitors. They are considered responsible for the beneficial effects of several traditional diets being present in green tea, extra virgin olive oil, red wine, spices, berries and aromatic herbs. Accordingly, it has been proposed that some natural phenols could be exploited to prevent and to treat amyloid diseases, and recent studies have provided significant information on their ability to inhibit peptide/protein aggregation in various ways and to stimulate cell defenses, leading to identify shared or specific mechanisms. In the first part of this review, we will overview the significance and mechanisms of amyloid aggregation and aggregate toxicity; then, we will summarize the recent achievements on protection against amyloid diseases by many natural phenols.

  2. Protein folding and aggregation into amyloid: the interference by natural phenolic compounds.

    Science.gov (United States)

    Stefani, Massimo; Rigacci, Stefania

    2013-01-01

    Amyloid aggregation is a hallmark of several degenerative diseases affecting the brain or peripheral tissues, whose intermediates (oligomers, protofibrils) and final mature fibrils display different toxicity. Consequently, compounds counteracting amyloid aggregation have been investigated for their ability (i) to stabilize toxic amyloid precursors; (ii) to prevent the growth of toxic oligomers or speed that of fibrils; (iii) to inhibit fibril growth and deposition; (iv) to disassemble preformed fibrils; and (v) to favor amyloid clearance. Natural phenols, a wide panel of plant molecules, are one of the most actively investigated categories of potential amyloid inhibitors. They are considered responsible for the beneficial effects of several traditional diets being present in green tea, extra virgin olive oil, red wine, spices, berries and aromatic herbs. Accordingly, it has been proposed that some natural phenols could be exploited to prevent and to treat amyloid diseases, and recent studies have provided significant information on their ability to inhibit peptide/protein aggregation in various ways and to stimulate cell defenses, leading to identify shared or specific mechanisms. In the first part of this review, we will overview the significance and mechanisms of amyloid aggregation and aggregate toxicity; then, we will summarize the recent achievements on protection against amyloid diseases by many natural phenols. PMID:23765219

  3. Intestinal Epithelial Serum Amyloid A Modulates Bacterial Growth In Vitro and Pro-Inflammatory Responses in Mouse Experimental Colitis

    Directory of Open Access Journals (Sweden)

    Wang Yu

    2010-11-01

    Full Text Available Abstract Background Serum Amyloid A (SAA is a major acute phase protein of unknown function. SAA is mostly expressed in the liver, but also in other tissues including the intestinal epithelium. SAA reportedly has anti-bacterial effects, and because inflammatory bowel diseases (IBD result from a breakdown in homeostatic interactions between intestinal epithelia and bacteria, we hypothesized that SAA is protective during experimental colitis. Methods Intestinal SAA expression was measured in mouse and human samples. Dextran sodium sulfate (DSS colitis was induced in SAA 1/2 double knockout (DKO mice and in wildtype controls. Anti-bacterial effects of SAA1/2 were tested in intestinal epithelial cell lines transduced with adenoviral vectors encoding the CE/J SAA isoform or control vectors prior to exposure to live Escherichia coli. Results Significant levels of SAA1/SAA2 RNA and SAA protein were detected by in situ hybridization and immunohistochemistry in mouse colonic epithelium. SAA3 expression was weaker, but similarly distributed. SAA1/2 RNA was present in the ileum and colon of conventional mice and in the colon of germfree mice. Expression of SAA3 was strongly regulated by bacterial lipopolysaccharides in cultured epithelial cell lines, whereas SAA1/2 expression was constitutive and not LPS inducible. Overexpression of SAA1/2 in cultured epithelial cell lines reduced the viability of co-cultured E. coli. This might partially explain the observed increase in susceptibility of DKO mice to DSS colitis. SAA1/2 expression was increased in colon samples obtained from Crohn's Disease patients compared to controls. Conclusions Intestinal epithelial SAA displays bactericidal properties in vitro and could play a protective role in experimental mouse colitis. Altered expression of SAA in intestinal biopsies from Crohn's Disease patients suggests that SAA is involved in the disease process..

  4. The metazoan protein disaggregase and amyloid depolymerase system: Hsp110, Hsp70, Hsp40, and small heat shock proteins.

    Science.gov (United States)

    Torrente, Mariana P; Shorter, James

    2013-01-01

    A baffling aspect of metazoan proteostasis is the lack of an Hsp104 ortholog that rapidly disaggregates and reactivates misfolded polypeptides trapped in stress induced disordered aggregates, preamyloid oligomers, or amyloid fibrils. By contrast, in bacteria, protozoa, chromista, fungi, and plants, Hsp104 orthologs are highly conserved and confer huge selective advantages in stress tolerance. Moreover, in fungi, the amyloid remodeling activity of Hsp104 has enabled deployment of prions for various beneficial modalities. Thus, a longstanding conundrum has remained unanswered: how do metazoan cells renature aggregated proteins or resolve amyloid fibrils without Hsp104? Here, we highlight recent advances that unveil the metazoan protein-disaggregase machinery, comprising Hsp110, Hsp70, and Hsp40, which synergize to dissolve disordered aggregates, but are unable to rapidly solubilize stable amyloid fibrils. However, Hsp110, Hsp70, and Hsp40 exploit the slow monomer exchange dynamics of amyloid, and can slowly depolymerize amyloid fibrils from their ends in a manner that is stimulated by small heat shock proteins. Upregulation of this system could have key therapeutic applications in various protein-misfolding disorders. Intriguingly, yeast Hsp104 can interface with metazoan Hsp110, Hsp70, and Hsp40 to rapidly eliminate disease associated amyloid. Thus, metazoan proteostasis is receptive to augmentation with exogenous disaggregases, which opens a number of therapeutic opportunities. PMID:24401655

  5. The acute phase response of haptoglobin and serum amyloid A (SAA) in cattle undergoing experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Heegaard, Peter M. H.; Godson, D.L.

    2000-01-01

    The ability of a pure virus infection to induce an acute phase protein response is of interest as viral infections are normally considered to be less efficient in inducing an acute phase protein response than bacterial infections. This was studied in a bovine model for infection with bovine respiratory syncytial virus (BRSV), analysing the induction of the two most dominant bovine acute phase proteins haptoglobin and serum amyloid A (SAA). Strong and reproducible acute phase responses were detected for both proteins, peaking at around 7-8 days after inoculation of BRSV, while no response was seen in mock-inoculated control animals. The serum concentrations reached for SAA and haptoglobin during the BRSV-induced acute phase response were generally the same or higher than previously reported for bacterial infections in calves. The magnitude and the duration of the haptoglobin response was found to correlate well with the severity of clinical signs (fever) and with the extent of lung consolidation while SAA responded most rapidly to infection.

  6. Membrane-protein interactions hold the key to understanding amyloid formation

    CERN Document Server

    Straub, John E

    2014-01-01

    In this perspective we describe the critical role membranes play in modulating the structures of the Amyloid Precursor Proteins to produce the peptides involved in the Alzheimer's disease. Some of the key concepts related to protein aggregation including the potential role of the excited states of monomers in initiating protein aggregation are described.

  7. Biochemical studies in Normal Pressure Hydrocephalus (NPH) patients: Change in CSF levels of amyloid precursor protein (APP), amyloid-beta (A?) peptide and phospho-tau

    OpenAIRE

    Ray, Balmiki; Reyes, Patricio F.; Lahiri, Debomoy K.

    2010-01-01

    Normal Pressure Hydrocephalus (NPH) is one of the causes of dementia of the elderly characterized by impaired mental function, gait difficulties and urinary incontinence. Previously, it was proposed that some of the NPH patients may develop Alzheimer’s disease (AD) like pathology. Aim of this study was to compare levels of different CSF biomarkers, including total secreted ?-amyloid precursor protein (sAPP), sAPP-alpha form (sAPP?), amyloid-beta (A?) peptide, total-tau protein and hyperphosph...

  8. Predicted alpha-helical regions of the prion protein when synthesized as peptides form amyloid.

    OpenAIRE

    Gasset, M.; Baldwin, M. A.; Lloyd, D. H.; Gabriel, J M; Holtzman, D.M.; F. Cohen; Fletterick, R; Prusiner, S. B.

    1992-01-01

    By comparing the amino acid sequences of 11 mammalian and 1 avian prion proteins (PrP), structural analyses predicted four alpha-helical regions. Peptides corresponding to these regions of Syrian hamster PrP were synthesized, and, contrary to predictions, three of the four spontaneously formed amyloids as shown by electron microscopy and Congo red staining. By IR spectroscopy, these amyloid peptides exhibited secondary structures composed largely of beta-sheets. The first of the predicted hel...

  9. Sortilin and SorLA Display Distinct Roles in Processing and Trafficking of Amyloid Precursor Protein

    DEFF Research Database (Denmark)

    Gustafsen, Camilla; Glerup, Simon; Pallesen, Lone Tjener; Olsen, Ditte; Andersen, Olav M; Nykjær, Anders; Madsen, Peder; Petersen, Claus Munck

    2013-01-01

    The development and progression of Alzheimer's disease is linked to excessive production of toxic amyloid-? peptide, initiated by ?-secretase cleavage of the amyloid precursor protein (APP). In contrast, soluble APP? (sAPP?) generated by the ?-secretase is known to stimulate dendritic branching and enhance synaptic function. Regulation of APP processing, and the shift from neurotrophic to neurotoxic APP metabolism remains poorly understood, but the cellular localization of APP and its interactio...

  10. Cleavage of amyloid precursor protein by an archaeal presenilin homologue PSH

    OpenAIRE

    Dang, Shangyu; Wu, Shenjie; Wang, Jiawei; Li, Hongbo; Huang, Min; He, Wei; LI, YUE-MING; Wong, Catherine C. L; Shi, Yigong

    2015-01-01

    Amyloid precursor protein (APP) is cleaved by ?-secretase to produce APP C99, which undergoes additional, sequential cleavages by ?-secretase to generate amyloid-? peptides including A?40 and A?42. Increased ratios of A?42 over A?40 are thought to cause Alzheimer’s disease. Screening of ?-secretase modulators is hindered by the technical challenges in expression and biochemical manipulation of ?-secretase. In this study, we demonstrate that the archaeal intramembrane protease PSH represents a...

  11. AMP-activated Protein Kinase Signaling Activation by Resveratrol Modulates Amyloid-? Peptide Metabolism*

    OpenAIRE

    Vingtdeux, Valérie; Giliberto, Luca; Zhao, Haitian; Chandakkar, Pallavi; Wu, Qingli; James E. Simon; Janle, Elsa M; Lobo, Jessica; Ferruzzi, Mario G.; Davies, Peter; Marambaud, Philippe

    2010-01-01

    Alzheimer disease is an age-related neurodegenerative disorder characterized by amyloid-? (A?) peptide deposition into cerebral amyloid plaques. The natural polyphenol resveratrol promotes anti-aging pathways via the activation of several metabolic sensors, including the AMP-activated protein kinase (AMPK). Resveratrol also lowers A? levels in cell lines; however, the underlying mechanism responsible for this effect is largely unknown. Moreover, the bioavailability of resveratrol in the brain...

  12. Idiopathic amyloidosis in the stone marten (Martes foina): identification of amyloid fibril proteins in tissue sections using the immunoperoxidase technique.

    Science.gov (United States)

    Linke, R P; Geisel, O; Eulitz, M; Nathrath, W B

    1980-12-01

    Amyloid fibril proteins isolated from a spleen of a wild stone marten (Martes foina, Exleben) with idiopathic amyloidosis show resemblance to protein AA by amino acid analysis. An antiserum directed against these proteins can be used to identify the marten's amyloid in formalin-fixed tissue paraffin-embedded sections using the immunoperoxidase method. PMID:7004540

  13. Serum amyloid A, haptoglobin, and ferritin in horses with colic: Association with common clinicopathological variables and short-term outcome.

    Science.gov (United States)

    Dondi, Francesco; Lukacs, Robert M; Gentilini, Fabio; Rinnovati, Riccardo; Spadari, Alessandro; Romagnoli, Noemi

    2015-07-01

    Equine colic may be associated with an acute phase response (APR). Measurement of acute phase proteins (APPs) allows the detection of an APR and may help clinicians in monitoring the disease; however, the role of APPs in colic is unclear. This study aimed to evaluate the clinical usefulness of serum amyloid A (SAA), haptoglobin and ferritin in combination with an extended clinicopathological profile in equine colic. The medical records of 54 horses were retrospectively selected. Horses were grouped based on outcome (survivors vs. non-survivors), diagnosis (ischaemic/strangulating vs. non-ischaemic/non-strangulating), and treatment (medical treatment vs. surgery). Laboratory data were compared, and a logistic regression analysis was performed for outcome prediction upon admission. A high percentage of horses had abnormal SAA (29/54), haptoglobin (20/54), and ferritin (31/54) concentrations. In particular, haptoglobin was below the reference interval in 13/54 horses. Non-survivors had significantly decreased haptoglobin and increased ferritin concentrations compared with survivors. The ischaemic/strangulating group had significantly increased creatinine and ferritin and decreased haptoglobin concentrations compared with the non-ischaemic/non-strangulating group. Creatinine was the only significant predictor of mortality in the regression analysis. In conclusion, APPs including SAA, haptoglobin, and ferritin combined with clinicopathological variables may help clinicians to understand the pathogenesis of APR and underline potential complications of equine colic. The reduction in haptoglobin concentration may suggest haemolysis or muscle fibre damage; ferritin may indicate alteration in iron metabolism and tissue damage. Further prospective studies are needed to assess diagnostic and prognostic values of APPs in colic horses. PMID:25981935

  14. Elevated levels of serum amyloid A indicate poor prognosis in patients with esophageal squamous cell carcinoma

    International Nuclear Information System (INIS)

    Increase of Serum amyloid A (SAA) level has been observed in patients with a variety of cancers. The objective of this study was to determined whether SAA level could be used as a prognostic parameter in patients with esophageal squamous cell carcinoma (ESCC). SAA levels were measured by rate nephelometry immunoassay in 167 healthy controls and 167 ESCC patients prior to surgical resection. Statistical associations between clinicopathological observations and SAA levels were determined using the Mann–Whitney U test. The clinical value of SAA level as a prognostic parameter was evaluated using the Cox’s proportional hazards model. SAA levels were significantly higher in patients with ESCC compared to levels in healthy controls (13.88 ± 15.19 mg/L vs. 2.26 ± 1.66 mg/L, P < 0.001). Elevation of SAA levels (? 8.0 mg/L) was observed in 54.5% (91/167) of patients with ESCC but not in healthy controls. SAA levels were associated with tumor size (P < 0.001), histological differentiation (P = 0.015), T classification (P < 0.001), clinical stage (P < 0.001), lymph node metastasis (P < 0.001) and distant metastasis (P < 0.001), but not with the age and gender of the patients or tumor location. Multivariate analysis revealed that patients with an elevated level of SAA (? 8.0 mg/L) had significantly lower 5-year survival rate than those with non-elevated SAA (< 8.0 mg/L, log-rank P < 0.0001). An elevated level of preoperative SAA was found to associate with tumor progression and poor survival in patients with ESCC

  15. Investigation of amyloid deposition in uterine leiomyoma patients

    OpenAIRE

    Jinping Liu; Fei Zhai; Peng Ge; Jinhai Lu; Yi Qin; Xuguo Sun

    2012-01-01

    Objects: To investigate the pathogenesis of amyloid presented in uterine leiomyoma. Methods: 36 uterine leiomyoma patients were recruited and divided into two groups according to Congo red staining results. 6 cases are Congo red staining-positive, and 30 cases Congo red staining-negative which represented amyloid positive and amyloid negative respectively. All patients’ serum total protein (TP), albumin (Alb) and prealbumin (PA) levels were measured as well as blood hemoglobin (Hb), cell coun...

  16. Amyloid-related biomarkers and axonal damage proteins in parkinsonian syndromes

    DEFF Research Database (Denmark)

    Bech, Sara; Hjermind, Lena E

    2012-01-01

    Clinical differentiation between parkinsonian syndromes (PS) remains a challenge despite well-established clinical diagnostic criteria. Specific diagnostic biomarkers have yet to be identified, though in recent years, studies have been published on the aid of certain brain related proteins (BRP) in the diagnosing of PS. We investigated the levels of the light subunit of neurofilament triplet protein (NF-L), total tau and phosphorylated tau, amyloid-?(1-42), and the soluble ?- and ?-cleaved fragments of amyloid precursor proteins in a cohort of patients with various PS.

  17. ?-Secretase processing of the Alzheimer amyloid-? precursor protein and its homolog APLP2

    OpenAIRE

    Jacobsen, Kristin

    2013-01-01

    The amyloid-? precursor protein (APP) has been widely studied due to its role in Alzheimer´s disease (AD). When APP is sequentially cleaved by ?- and ?-secretase, amyloid-? (A?) is formed. A? is prone to aggregate and is toxic to neurons. However, the main processing pathway for APP involves initial cleavage at the ?-site, within the A? region, instead generating a neuroprotective soluble fragment, sAPP?. APP is a member of a protein family, also including the proteins APLP1 and APLP2, which ...

  18. Self-assembling of amyloid-like proteins

    Energy Technology Data Exchange (ETDEWEB)

    Sales, E.M.; Barbosa, L.R.S.; Itri, R. [Universidade de Sao Paulo (USP), SP (Brazil); Damalio, J.C.P.; Araujo, A.P.U. [Universidade de Sao Paulo (USP-SC), Sao Carlos, SP (Brazil); Spinozzi, F.; Mariani, P. [Universita Politecnica delle Marche, Ancona (Italy)

    2012-07-01

    Full text: Septins are proteins from the GTP-binding family and participate in cell division cycle performing functions such as secretion and cytoskeletal division. They can also be found in neurodegenerative conditions as Alzheimers and Parkinson's diseases, forming highly organized fiber-like aggregates known as amyloids. In this work, we used small angle x-ray scattering (SAXS) to investigate the formation and time evolution of septins aggregates under the influence of temperature and concentration. The SAXS measurements were performed with the GTPase domain of human Septin 2 (SEPT2G) at 0.5 and 1 mg/mL and temperatures between 4 and 45 deg C. At 0.5 mg/mL and 4 deg C, the protein self-aggregates as a dimer, being stable over one hour of observation. When the temperature was increased to 15 deg C, the results demonstrate that cylinder-like aggregates are formed and coexist with some dimer population and a small amount of larger aggregates. However, the number of very large aggregates increases with time concomitantly with the decrease of cylinder amount in the solution. At 37 deg C cylinder-like aggregates are not longer present in solution, whereas a significant amount of dimers decreases from 50% to 20% in less than 1 hour. At 45 deg C such an effect is even more accentuated: the percentage of dimers is only 6% in solution into a favor of 94% of very larger aggregates. When we analyze the protein at 1 mg/mL, at 4 deg C cylinder-like aggregates (36 nm-long and 12 nm-cross section) are already formed, coexisting with dimers and, as occurred for lower concentration, the two populations remained unchanged over one hour of observation. Out results also indicate that the dimensions of these cylinders increase with the concentration and the percentage of cylinders and larger aggregates are higher than those found for 0.5 mg/mL. In conclusion, our results showed the coexistence of dimers of SEPT2G with small fibers and larger aggregates in solution that evolve not only with concentration and temperature but also with time. (author)

  19. Self-assembling of amyloid-like proteins

    International Nuclear Information System (INIS)

    Full text: Septins are proteins from the GTP-binding family and participate in cell division cycle performing functions such as secretion and cytoskeletal division. They can also be found in neurodegenerative conditions as Alzheimers and Parkinson's diseases, forming highly organized fiber-like aggregates known as amyloids. In this work, we used small angle x-ray scattering (SAXS) to investigate the formation and time evolution of septins aggregates under the influence of temperature and concentration. The SAXS measurements were performed with the GTPase domain of human Septin 2 (SEPT2G) at 0.5 and 1 mg/mL and temperatures between 4 and 45 deg C. At 0.5 mg/mL and 4 deg C, the protein self-aggregates as a dimer, being stable over one hour of observation. When the temperature was increased to 15 deg C, the results demonstrate that cylinder-like aggregates are formed and coexist with some dimer population and a small amount of larger aggregates. However, the number of very large aggregates increases with time concomitantly with the decrease of cylinder amount in the solution. At 37 deg C cylinder-like aggregates are not longer present in solution, whereas a significant amount of dimers decreases from 50% to 20% in less than 1 hour. At 45 deg C such an effect is even more accentuated: the percentage of dimers is only 6% in solution into a favor of 94% of very larger aggregates. When we analyze the protein at 1 mg/mL, at 4 deg C cylinder-like aggregates (36 nm-long and 12 nm-cross section) are already formed, coexisting with dimers and, as occurred for lower concentration, the two populations remained unchanged over one hour of observation. Out results also indicate that the dimensions of these cylinders increase with the concentration and the percentage of cylinders and larger aggregates are higher than those found for 0.5 mg/mL. In conclusion, our results showed the coexistence of dimers of SEPT2G with small fibers and larger aggregates in solution that evolve not only with concentration and temperature but also with time. (author)

  20. Serum amyloid A and pairing formyl peptide receptor 2 are expressed in corneas and involved in inflammation-mediated neovascularization

    Directory of Open Access Journals (Sweden)

    Sheng-Wei Ren

    2014-04-01

    Full Text Available AIM:To solidify the involvement of Saa-related pathway in corneal neovascularization (CorNV. The pathogenesis of inflammatory CorNV is not fully understood yet, and our previous study implicated that serum amyloid A (Saa 1 (Saa1 and Saa3 were among the genes up-regulated upon CorNV induction in mice.METHODS:Microarray data obtained during our profiling project on CorNV were analyzed for the genes encoding the four SAA family members (Saa1-4, six reported SAA receptors (formyl peptide receptor 2, Tlr2, Tlr4, Cd36, Scarb1, P2rx7 and seven matrix metallopeptidases (Mmp 1a, 1b, 2, 3, 9, 10, 13 reportedly to be expressed upon SAA pathway activation. The baseline expression or changes of interested genes were further confirmed in animals with CorNV using molecular or histological methods. CorNV was induced in Balb/c and C57BL/6 mice by placing either three interrupted 10-0 sutures or a 2 mm filter paper soaked with sodium hydroxide in the central area of the cornea. At desired time points, the corneas were harvested for histology examination or for extraction of mRNA and protein. The mRNA levels of Saa1, Saa3, Fpr2, Mmp2 and Mmp3 in corneas were detected using quantitative reverse transcription-PCR, and SAA3 protein in tissues detected using immunohistochemistry or western blotting.RESULTS:Microarray data analysis revealed that Saa1, Saa3, Fpr2, Mmp2, Mmp3 messengers were readily detected in normal corneas and significantly up-regulated upon CorNV induction. The changes of these five genes were confirmed with real-time PCR assay. On the contrary, other SAA members (Saa2, Saa4, other SAA receptors (Tlr2, Tlr4, Cd36, P2rx7, etc, or other Mmps (Mmp1a, Mmp1b, Mmp9, Mmp10, Mmp13 did not show consistent changes. Immunohistochemistry study and western blotting further confirmed the expression of SAA3 products in normal corneas as well as their up-regulation in corneas with CorNV.CONCLUSION:SAA-FPR2 pathway composing genes were expressed in normal murine corneas and, upon inflammatory stimuli challenge to the corneas, their expressions were up-regulated, suggesting their roles in pathogenesis of CorNV. The potential usefulness of SAA-FPR2 targets in future management of CorNV-related diseases deserves investigation.

  1. Physiological functions of the amyloid precursor protein secretases ADAM10, BACE1, and presenilin.

    Science.gov (United States)

    Prox, Johannes; Rittger, Andrea; Saftig, Paul

    2012-04-01

    Alzheimer's disease causing mutations in the amyloid precursor protein (APP) or in the Presenilin 1 (PS1) or Presenilin 2 (PS2) genes increase the production of amyloid peptides (A?) that precipitate in amyloid plaques. Since amyloid plaques are also a prominent feature of sporadic Alzheimer's disease (AD), abnormal proteolysis of APP and the generation of amyloid beta (A?) are key events in the pathogenesis of AD. The proteases (secretases) that cleave APP are therefore important therapeutic targets, both for the rare familial forms but likely also for the sporadic forms of AD. The identification and understanding of the (neuro)biological functions of the ?-, ?-, and presenilin/?-secretase (complexes) is important for the development of drugs and the delineation of their associated side effects. The potential impact of this type of research exceeds the AD field since the function of these secretases are also linked to cellular pathways like ectodomain shedding of growth factors and regulated intramembrane proteolysis of receptors in developmental biology, tissue homeostasis, and tumorigenesis. The generation of mice deficient in presenilin 1, presenilin 2, the ?-secretase ADAM10, and the ?-secretases BACE1 and BACE2 were instrumental for the elucidation of the physiological functions of these proteases. Using these mouse models understanding how these secretases regulate amyloid peptide formation and how they exert their diverse biological functions could be significantly increased. This review attempts to summarize selected aspects of the current view of the multiple roles such proteases play in health and disease. PMID:22120156

  2. Assessment of Oritavancin Serum Protein Binding across Species?

    OpenAIRE

    Arhin, Francis F.; Belley, Adam; McKay, Geoffrey; Beaulieu, Sylvain; Sarmiento, Ingrid; Parr, Thomas R.; Moeck, Gregory

    2010-01-01

    Biophysical methods to study the binding of oritavancin, a lipoglycopeptide, to serum protein are confounded by nonspecific drug adsorption to labware surfaces. We assessed oritavancin binding to serum from mouse, rat, dog, and human by a microbiological growth-based method under conditions that allow near-quantitative drug recovery. Protein binding was similar across species, ranging from 81.9% in human serum to 87.1% in dog serum. These estimates support the translation of oritavancin expos...

  3. Amyloid-clearing proteins and their epigenetic regulation as a therapeutic target in Alzheimer's disease.

    Science.gov (United States)

    Nalivaeva, Natalia N; Belyaev, Nikolai D; Kerridge, Caroline; Turner, Anthony J

    2014-01-01

    Abnormal elevation of amyloid ?-peptide (A?) levels in the brain is the primary trigger for neuronal cell death specific to Alzheimer's disease (AD). It is now evident that A? levels in the brain are manipulable due to a dynamic equilibrium between its production from the amyloid precursor protein (APP) and removal by amyloid clearance proteins. Clearance can be either enzymic or non-enzymic (binding/transport proteins). Intriguingly several of the main amyloid-degrading enzymes (ADEs) are members of the M13 peptidase family (neprilysin (NEP), NEP2 and the endothelin converting enzymes (ECE-1 and -2)). A distinct metallopeptidase, insulin-degrading enzyme (IDE), also contributes to A? degradation in the brain. The ADE family currently embraces more than 20 members, both membrane-bound and soluble, and of differing cellular locations. NEP plays an important role in brain function terminating neuropeptide signals. Its decrease in specific brain areas with age or after hypoxia, ischaemia or stroke contribute significantly to the development of AD pathology. The recently discovered mechanism of epigenetic regulation of NEP (and other genes) by the APP intracellular domain (AICD) and its dependence on the cell type and APP isoform expression suggest possibilities for selective manipulation of NEP gene expression in neuronal cells. We have also observed that another amyloid-clearing protein, namely transthyretin (TTR), is also regulated in the neuronal cell by a mechanism similar to NEP. Dependence of amyloid clearance proteins on histone deacetylases and the ability of HDAC inhibitors to up-regulate their expression in the brain opens new avenues for developing preventive strategies in AD. PMID:25278875

  4. The biodistribution and imaging of a novel amyloid probe 131I-serum amyloid P-component in mice model of amyloidosis

    International Nuclear Information System (INIS)

    Objective: To validate 131I-serum amyloid P-component (SAP) as a novel amyloid probe in mice bearing amyloidosis and evaluate its diagnostic value. Methods: Standard SAP was labeled with 131I using Iodogen method. Amyloidotic mice model was established by subcutaneous injection of 0.5 ml 10% Casein daily for 21 d, and the control group was injected with 0.5 ml saline. Both groups were injected with 7.4 MBq 131I-SAP through the tail veins and imaging was performed at 1, 3, 6, 24, 48 and 72 h post injection. In biodistribution study, 30 amyloidotic mice model and 30 controls were injected with 555 kBq 131I-SAP and were killed evenly at 1, 3, 6, 24, 48 and 72 h post injection. T test was used to analysis the data. Results: The labeling efficiency of 131I-SAP was 70.6%, and the radiochemical purity was ( 95.5 ±3.4)%. There was significant tracer uptake by liver, spleen and kidney at 24 h in the test group and mild uptake by these organs in the control group. The uptake ratios of liver, spleen and kidney over blood in the test group were 2.201 ±0.301, 2.139 ±0.223, 4.797 ±0.615, vs 0.657 ±0.126, 1.014 ±0.063, 0.607 ±0.028 in the control group,respectively (t=10.747, 11.626 and 15.135, all P<0.01). The uptake differences between the two groups were still statistically significant at 48 h (t=15.128, 4.558, 16.960, all P<0.01). The uptake ratios of spleen over blood between the two groups were not significantly different at 72 h (t=3.022, P>0.05), but the other two uptake ratios were both significantly different (t=7.801, 6.442, both P<0.01). Conclusions: SAP can be reliably labeled with 131I. The labeled product 131I-SAP can accumulate in amyloid laden tissues, thus rendering it a potential agent in the detection of amyloidosis. (authors)

  5. Prophylaxis and Treatment of Alzheimer's Disease by Delivery of an Adeno-Associated Virus Encoding a Monoclonal Antibody Targeting the Amyloid Beta Protein

    OpenAIRE

    Shimada, Masaru; Abe, Shinya; Takahashi, Toru; Shiozaki, Kazumasa; Okuda, Mitsue; Mizukami, Hiroaki; Klinman, Dennis M.; Ozawa, Keiya; Okuda, Kenji

    2013-01-01

    We previously reported on a monoclonal antibody (mAb) that targeted amyloid beta (Aß) protein. Repeated injection of that mAb reduced the accumulation of Aß protein in the brain of human Aß transgenic mice (Tg2576). In the present study, cDNA encoding the heavy and light chains of this mAb were subcloned into an adeno-associated virus type 1 (AAV) vector with a 2A/furin adapter. A single intramuscular injection of 3.0×1010 viral genome of these AAV vectors into C57BL/6 mice generated serum an...

  6. Adaptor protein 2–mediated endocytosis of the ?-secretase BACE1 is dispensable for amyloid precursor protein processing

    OpenAIRE

    Prabhu, Yogikala; Burgos, Patricia V.; Schindler, Christina; Farías, Ginny G; Magadár, Javier G.; Bonifacino, Juan S

    2012-01-01

    An adaptor protein complex, AP-2, is involved in the endocytosis of ?-secretase (BACE1) via the clathrin-dependent machinery. Endosomal targeting of either the amyloid precursor protein (APP) and/or BACE1 is expendable for the amyloidogenic processing of APP.

  7. Structure of a Functional Amyloid Protein Subunit Computed Using Sequence Variation

    DEFF Research Database (Denmark)

    Tian, Pengfei; Boomsma, Wouter

    2015-01-01

    Functional amyloid fibers, called curli, play a critical role in adhesion and invasion of many bacteria. Unlike pathological amyloids, curli structures are formed by polypeptide sequences whose amyloid structure has been selected for during evolution. This important distinction provides us with an opportunity to obtain structural insights from an unexpected source: the covariation of amino acids in sequences of different curli proteins. We used recently developed methods to extract amino acid contacts from a multiple sequence alignment of homologues of the curli subunit protein, CsgA. Together with an efficient force field, these contacts allow us to determine structural models of CsgA. We find that CsgA forms a ?-helical structure, where each turn corresponds to previously identified repeat sequences in CsgA. The proposed structure is validated by previously measured solid-state NMR, electron microscopy and X-ray diffraction data, and agrees with an earlier proposed model derived by complementary means.

  8. Functional Amyloid in Pseudomonas

    DEFF Research Database (Denmark)

    Dueholm, Morten Simonsen; Petersen, Steen V.; Sønderkær, Mads; Larsen, Poul; Christiansen, Gunna; Hein, Kim L.; Enghild, Jan J.; Nielsen, Jeppe Lund; Nielsen, Kåre Lehmann; Nielsen, Per Halkjær; Otzen, Daniel

    2010-01-01

    Summary Amyloids are highly abundant in many microbial biofilms and may play an important role in their architecture. Nevertheless, little is known of the amyloid proteins. We report the discovery of a novel functional amyloid expressed by a Pseudomonas strain of the P. fluorescens group. The amyloid protein was purified and the amyloid-like structure verified. Partial sequencing by MS/MS combined with full genomic sequencing of the Pseudomonas strain identified the gene coding for the major sub...

  9. Functional amyloid in Pseudomonas

    DEFF Research Database (Denmark)

    Dueholm, Morten S; Petersen, Steen V; Sønderkær, Mads; Larsen, Poul; Christiansen, Gunna; Hein, Kim L; Enghild, Jan J; Nielsen, Jeppe L; Nielsen, Kåre L; Nielsen, Per H; Otzen, Daniel E

    2010-01-01

    Summary Amyloids are highly abundant in many microbial biofilms and may play an important role in their architecture. Nevertheless, little is known of the amyloid proteins. We report the discovery of a novel functional amyloid expressed by a Pseudomonas strain of the P. fluorescens group. The amyloid protein was purified and the amyloid-like structure verified. Partial sequencing by MS/MS combined with full genomic sequencing of the Pseudomonas strain identified the gene coding for the major sub...

  10. What drives an amyloid protein precursor from an amyloidogenic to a native-like aggregation pathway?

    OpenAIRE

    Quintas, Alexandre

    2013-01-01

    Conformational disorders such as Alzheimer’s, Parkinson’s, familial amyloidotic polyneuropathy and spongiform encephalopaties are a consequence of protein misfolding and aggregation predominantly in the form of amyloid fibrils. These pathologies represent a major health problem, which most probably will overwhelm the health systems of developed countries in the near future. Significant progress has been made recently to understanding the underlying mecha...

  11. Mediator is a transducer of amyloid-precursor-protein-dependent nuclear signalling

    OpenAIRE

    Xu, Xuan; ZHOU, HAIYING; Boyer, Thomas G.

    2011-01-01

    MED12, an RNA Polymerase II Mediator subunit implicated in human cognitive development, is identified as a critical transcriptional coactivator of the amyloid precursor protein (APP) intracellular domain, implicating MED12/Mediator in a broad range of developmental and pathological processes driven by APP signal transduction.

  12. Macroautophagy Is Not Directly Involved in the Metabolism of Amyloid Precursor Protein*

    OpenAIRE

    Boland, Barry; Smith, David A.; Mooney, Declan; Jung, Sonia S.; Walsh, Dominic M; Platt, Frances M.

    2010-01-01

    Alterations in the metabolism of amyloid precursor protein (APP) are believed to play a central role in Alzheimer disease pathogenesis. Burgeoning data indicate that APP is proteolytically processed in endosomal-autophagic-lysosomal compartments. In this study, we used both in vivo and in vitro paradigms to determine whether alterations in macroautophagy affect APP metabolism...

  13. Correlations between serum levels of beta amyloid, cerebrospinal levels of tau and phospho tau, and delayed response tasks in young and aged cynomolgus monkeys (Macaca fascicularis)

    DEFF Research Database (Denmark)

    Darusman, Huda Shalahudin; Sajuthi, D

    2013-01-01

    In an attempt to explore cynomolgus monkeys as an animal model for Alzheimer's disease, the present study focused on the Alzheimer's biomarkers beta amyloid 1-42 (A?42 ) in serum, and total tau (t-tau) and phosphorylated tau (p-tau) levels in cerebrospinal fluid.

  14. Effect of x-radiation on serum proteins

    International Nuclear Information System (INIS)

    The inbred albine mice were exposed to 315 roentgen whole-body X-radiation at a rate of 22.5 roentgen per minute. Maximum decrease in the serum albumin and maximum increase in the serum globulin fractions were seen two hours after irradiation. Both of the serum proteins return to approximately normal levels within six hours. (author)

  15. SorLA CR-Domains Protect the Amyloid Precursor Protein against Processing

    DEFF Research Database (Denmark)

    Mehmedbasic, Arnela; Christensen, Sofie K; Nilsson, Jonas; Rüetschi, Ulla; Gustafsen, Camilla; Poulsen, Annemarie Svane Aavild; Rasmussen, Rikke W; Fjorback, Anja N; Larson, Göran; Andersen, Olav M

    2014-01-01

    SorLA is a neuronal sorting receptor that is genetically associated with Alzheimer's disease. SorLA interacts directly with the amyloid precursor protein (APP) and affects the processing of the precursor, leading to a decreased generation of the amyloid-? (A?) peptide. The sorLA complement-type repeat (CR)-domains associate in vitro with APP, but the precise molecular determinants of sorLA-APP complex formation and the mechanisms responsible for the effect of binding on APP processing have not y...

  16. Transgenic Drosophila expressing human amyloid precursor protein show ?-secretase activity and a blistered-wing phenotype

    OpenAIRE

    Fossgreen, Anke; Brückner, Bodo; Czech, Christian; Masters, Colin L.; Beyreuther, Konrad; Paro, Renato

    1998-01-01

    The importance of the amyloid precursor protein (APP) in the pathogenesis of Alzheimer’s disease (AD) became apparent through the identification of distinct mutations in the APP gene, causing early onset familial AD with the accumulation of a 4-kDa peptide fragment (?A4) in amyloid plaques and vascular deposits. However, the physiological role of APP is still unclear. In this work, Drosophila melanogaster is used as a model system to analyze the function of APP by expressing wild-type and var...

  17. 99mTc-MAMA-chrysamine G, a probe for beta-amyloid protein of Alzheimer's disease

    International Nuclear Information System (INIS)

    Chrysamine G (CG), an analogue of Congo red, is known to bind in vitro to the ?-amyloid protein (A? 10-43) and to homogenates of several regions of the brain of Alzheimer's disease (AD) patients. We synthesised a conjugate of 2-(acetamido)-CG with a bis-S-trityl protected monoamide-monoaminedithiol (MAMA-Tr2) tetraligand, which was efficiently deprotected and labelled with a 75% yield with technetium-99m, to obtain 99mTc-MAMA-CG. In mice, 99mTc-MAMA-CG was cleared mainly by the hepatobiliary system, resulting in a fast blood clearance. Brain uptake of 99mTc-MAMA-CG was low. Co-injection with the blood pool tracer iodine-125 human serum albumin (125I-HSA) demonstrated a brain/blood activity ratio for 99mTc-MAMA-CG that was significantly higher than that for 125I-HSA (t test for dependent samples, P99mTc-MAMA-CG to cross the blood-brain barrier. In vitro autoradiography demonstrated pronounced binding of 99mTc-MAMA-CG to ?-amyloid deposits in autopsy sections of the parietal and occipital cortex of an AD patient as compared with controls. Adding 10 ?M Congo red during incubation displaced the binding of 99mTc-MAMA-CG. Congo red staining and autoradiography identified the same lesions. 99mTc-MAMA-CG seems to bind selectively to ?-amyloid deposition in human brain parenchyma and blood vessels in vitro and thus might be a lead compound for further development of a useful tracer agent for the in vivo diagnosis of Alzheimer's disease. (orig.)

  18. EFhd2 is a novel amyloid protein associated with pathological tau in Alzheimer's disease.

    Science.gov (United States)

    Ferrer-Acosta, Yancy; Rodríguez-Cruz, Eva N; Orange, François; De Jesús-Cortés, Hector; Madera, Bismark; Vaquer-Alicea, Jaime; Ballester, Juan; Guinel, Maxime J-F; Bloom, George S; Vega, Irving E

    2013-06-01

    EFhd2 is a conserved calcium-binding protein, abundant within the central nervous system. Previous studies identified EFhd2 associated with pathological forms of tau proteins in the tauopathy mouse model JNPL3, which expresses the human tau(P301L) mutant. This association was validated in human tauopathies, such as Alzheimer's disease (AD). However, the role that EFhd2 may play in tauopathies is still unknown. Here, we show that EFhd2 formed amyloid structures in vitro, a capability that is reduced by calcium ions. Electron microscopy (EM) analyses demonstrated that recombinant EFhd2 formed filamentous structures. EM analyses of sarkosyl-insoluble fractions derived from human AD brains also indicated that EFhd2 co-localizes with aggregated tau proteins and formed granular structures. Immunohistological analyses of brain slices demonstrated that EFhd2 co-localizes with pathological tau proteins in AD brains, confirming the co-aggregation of EFhd2 and pathological tau. Furthermore, EFhd2's coiled-coil domain mediated its self-oligomerization in vitro and its association with tau proteins in JNPL3 mouse brain extracts. The results demonstrate that EFhd2 is a novel amyloid protein associated with pathological tau proteins in AD brain and that calcium binding may regulate the formation of EFhd2's amyloid structures. Hence, EFhd2 may play an important role in the pathobiology of tau-mediated neurodegeneration. PMID:23331044

  19. Prion and Nonprion Amyloids: A Comparison Inspired by the Yeast Sup35 Protein

    OpenAIRE

    Kushnirov, Vitaly V; Vishnevskaya, Aleksandra B.; Alexandrov, Ilya M.; Ter-Avanesyan, Michael D.

    2007-01-01

    Yeast prion determinants are related to polymerization of some proteins into amyloid-like fibers. The [PSI+] determinant reflects polymerization of the Sup35 protein. Fragmentation of prion polymers by the Hsp104 chaperone represents a key step of the prion replication cycle. The frequency of fragmentation varies depending on the structure of the prion polymers and defines variation in the prion phenotypes, e.g., the suppressor strength of [PSI+] and stability of its inheritance. Besides [PSI...

  20. Amyloid-related biomarkers and axonal damage proteins in parkinsonian syndromes

    DEFF Research Database (Denmark)

    Bech, Sara; Hjermind, Lena E; Salvesen, Lisette; Nielsen, Jørgen E; Heegaard, Niels H H; Jørgensen, Henrik L; Rosengren, Lars; Blennow, Kaj; Zetterberg, Henrik; Winge, Kristian

    2012-01-01

    Clinical differentiation between parkinsonian syndromes (PS) remains a challenge despite well-established clinical diagnostic criteria. Specific diagnostic biomarkers have yet to be identified, though in recent years, studies have been published on the aid of certain brain related proteins (BRP) in the diagnosing of PS. We investigated the levels of the light subunit of neurofilament triplet protein (NF-L), total tau and phosphorylated tau, amyloid-ß(1-42), and the soluble a- and ß-cleaved fragm...

  1. Metalloprotease Meprin ? Generates Nontoxic N-terminal Amyloid Precursor Protein Fragments in Vivo*

    OpenAIRE

    Jefferson, Tamara; ?auševi?, Mirsada; Auf dem Keller, Ulrich; Schilling, Oliver; Isbert, Simone; Geyer, Rebecca; Maier, Wladislaw; Tschickardt, Sabrina; Jumpertz, Thorsten; Weggen, Sascha; Bond, Judith S.; Overall, Christopher M; Pietrzik, Claus U.; Becker-Pauly, Christoph

    2011-01-01

    Identification of physiologically relevant substrates is still the most challenging part in protease research for understanding the biological activity of these enzymes. The zinc-dependent metalloprotease meprin ? is known to be expressed in many tissues with functions in health and disease. Here, we demonstrate unique interactions between meprin ? and the amyloid precursor protein (APP). Although APP is intensively studied as a ubiquitously expressed cell surface protein, which is involved i...

  2. Serum Surfactant Protein D: Biomarker of Chronic Obstructive Pulmonary Disease

    OpenAIRE

    Chun-Rong Ju; Wei Liu; Rong-Chang Chen

    2012-01-01

    Background: Surfactant protein D (SP-D) is a lung-specific protein proposed to predict clinical outcomes in patients with chronic obstructive pulmonary disease (COPD). However, the changes in serum SP-D during acute exacerbation (AECOPD) episodes and the relationship of serum SP-D with the overall severity of the disease in stable COPD (SCOPD) remain unclear.

  3. Multiplexed microfluidic quantification of proteins in serum

    Science.gov (United States)

    Rajan, Nitin; Rajauria, Sukumar; Cleland, Andrew

    2015-03-01

    Rapid and low cost immunoassays targeting proteins in blood or other bodily fluids are highly sought after for point-of-care devices and early screening of patients. Immunoturbidimetric assays utilize latex particles functionalized with antibodies, with particle aggregation in the presence of the analyte detected by a change in absorbance. Using a high throughput micro-fluidic particle analyzer based solely on electrical signals (resistive pulse sensing), we are able to accurately quantify the degree of aggregation by analyzing the changes in the particle size distribution. Thus we study the aggregation of streptavidin (SAv) coated beads in the presence of biotinylated bovine serum albumin as a proof-of-principle assay and extract the binding capacity of the SAv beads from the dose-response curve. We also use our aggregation measurement platform to characterize a commercial C-reactive protein (CRP) immunoturbidimetric assay (hsCRP, Diazyme Inc.). We obtain a linear calibration curve as well as a better limit of detection of CRP than that obtained by absorbance measurements. By using different bead sizes functionalized with different antibodies, multiplexed analyte detection is also possible. We demonstrate this by combining the commercial anti-CRP functionalized beads (0.4 microns) with biotin coated beads (1.0 microns), and carry out the simultaneous detection of SAv and CRP in a single sample.

  4. Heterocomplexes of mannose-binding lectin and the pentraxins PTX3 or serum amyloid P component trigger cross-activation of the complement system

    DEFF Research Database (Denmark)

    Ma, Ying Jie; Doni, Andrea

    2011-01-01

    The long pentraxin 3 (PTX3), serum amyloid P component (SAP), and C-reactive protein belong to the pentraxin family of pattern recognition molecules involved in tissue homeostasis and innate immunity. They interact with C1q from the classical complement pathway. Whether this also occurs via the analogous mannose-binding lectin (MBL) from the lectin complement pathway is unknown. Thus, we investigated the possible interaction between MBL and the pentraxins. We report that MBL bound PTX3 and SAP partly via its collagen-like domain but not C-reactive protein. MBL-PTX3 complex formation resulted in recruitment of C1q, but this was not seen for the MBL-SAP complex. However, both MBL-PTX3 and MBL-SAP complexes enhanced C4 and C3 deposition and opsonophagocytosis of Candida albicans by polymorphonuclear leukocytes. Interaction between MBL and PTX3 led to communication between the lectin and classical complement pathways via recruitment of C1q, whereas SAP-enhanced complement activation occurs via a hitherto unknown mechanism. Taken together, MBL-pentraxin heterocomplexes trigger cross-activation of the complement system.

  5. Elemental analysis of human serum and serum protein fractions by thermal neutron activation

    International Nuclear Information System (INIS)

    Some applications of thermal neutron activation for the determination of elemental contents in human serum and human serum protein fractions are presented. Firstly total serum is dealt with, secondly serum protein fractions obtained by gel filtration are described. A brief review on the role of (trace) elements in human health and disease and a compilation of literature data for elemental contents in human serum, as obtained by neutron activation techniques, are given. The most important sources of statistical and systematic errors are evaluated. Results for the contents of sodium, potassium, magnesium, bromine, iron, copper, zinc, selenium, rubidium, cesium and antimony in serum are given, with emphasis on control of accuracy and precision. The possible relation between selenium in blood and cancer occurrence in humans is discussed. The results of elemental analyses from cancer patients and from a patient receiving a cytostatic treatment are presented. A survey of literature results for the determination of protein-bound elemental contents in serum is presented. Subsequently, results from a study on the behaviour of elements during gel filtration are discussed. Gel-element and protein-element interactions are studied. Finally the protein-bound occurrence of trace elements in human serum is determined by gel filtration and neutron activation analysis. Results for both desalting and fractionation are given, for the elements bromine, copper, manganese, vanadium, selenium, zinc, rubidium, iron and iodine. (Auth.)

  6. Molecular simulations of beta-amyloid protein near hydrated lipids (PECASE).

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Aidan Patrick; Han, Kunwoo (Texas A& M University, College Station, TX); Ford, David M. (Texas A& M University, College Station, TX)

    2005-12-01

    We performed molecular dynamics simulations of beta-amyloid (A{beta}) protein and A{beta} fragment(31-42) in bulk water and near hydrated lipids to study the mechanism of neurotoxicity associated with the aggregation of the protein. We constructed full atomistic models using Cerius2 and ran simulations using LAMMPS. MD simulations with different conformations and positions of the protein fragment were performed. Thermodynamic properties were compared with previous literature and the results were analyzed. Longer simulations and data analyses based on the free energy profiles along the distance between the protein and the interface are ongoing.

  7. Mapping of the gene encoding the ?-amyloid precursor protein and its relationship to the Down syndrome region of chromosome 21

    International Nuclear Information System (INIS)

    The gene encoding the ?-amyloid precursor protein has been assigned to human chromosome 21, as has a gene responsible for at least some cases of familial Alzheimer disease. Linkage studies strongly suggest that the ?-amyloid precursor protein and the product corresponding to familial Alzheimer disease are from two genes, or at least that several million base pairs of DNA separate the markers. The precise location of the ?-amyloid precursor protein gene on chromosome 21 has not yet been determined. Here the authors show, by using a somatic-cell/hybrid-cell mapping panel, in situ hybridization, and transverse-alternating-field electrophoresis, that the ?-amyloid precursor protein gene is located on chromosome 21 very near the 21q21/21q/22 border and probably within the region of chromosome 21 that, when trisomic, results in Down syndrome

  8. Brain Trauma Induces Massive Hippocampal Neuron Death Linked to a Surge in ?-Amyloid Levels in Mice Overexpressing Mutant Amyloid Precursor Protein

    OpenAIRE

    Smith, Douglas H; Nakamura, Michio; McIntosh, Tracy K.; Wang, Jun; Rodríguez, Amarís; Chen, Xiao-Han; Raghupathi, Ramesh; Saatman, Kathryn E; Clemens, James; Schmidt, M. Luise; Lee, Virginia M-Y.; Trojanowski, John Q.

    1998-01-01

    Although brain trauma is a risk factor for Alzheimer’s disease, no experimental model has been generated to explore this relationship. We developed a model of brain trauma in transgenic mice that overexpress mutant human amyloid precursor protein (PDAPP) leading to the appearance of Alzheimer’s disease-like ?-amyloid (A?) plaques beginning at 6 months of age. We induced cortical impact brain injury in the PDAPP animals and their wild-type littermates at 4 months of age, ie, before A? plaque f...

  9. The Effects of Endogenous Non-Peptide Molecule Isatin and Hydrogen Peroxide on Proteomic Profiling of Rat Brain Amyloid-? Binding Proteins: Relevance to Alzheimer’s Disease?

    Directory of Open Access Journals (Sweden)

    Alexei E. Medvedev

    2014-12-01

    Full Text Available The amyloid-? peptide is considered as a key player in the development and progression of Alzheimer’s disease (AD. Although good evidence exists that amyloid-? accumulates inside cells, intracellular brain amyloid-binding proteins remain poorly characterized. Proteomic profiling of rat brain homogenates, performed in this study, resulted in identification of 89 individual intracellular amyloid-binding proteins, and approximately 25% of them were proteins that we had previously identified as specifically binding to isatin, an endogenous neuroprotector molecule. A significant proportion of the amyloid-binding proteins (more than 30% are differentially expressed or altered/oxidatively modified in AD patients. Incubation of brain homogenates with 70 µM hydrogen peroxide significantly influenced the profile of amyloid-? binding proteins and 0.1 mM isatin decreased the number of identified amyloid-? binding proteins both in control and hydrogen peroxide treated brain homogenates. The effects of hydrogen peroxide and isatin have been confirmed in optical biosensor experiments with purified glyceraldehyde-3-phosphate dehydrogenase, one of the known crucial amyloid-? binding proteins (also identified in this study. Data obtained suggest that isatin protects crucial intracellular protein targets against amyloid binding, and possibly favors intracellular degradation of this protein via preventing formation of amyloid-? oligomers described in the literature for some isatin derivatives.

  10. The Effects of Endogenous Non-Peptide Molecule Isatin and Hydrogen Peroxide on Proteomic Profiling of Rat Brain Amyloid-? Binding Proteins: Relevance to Alzheimer’s Disease?

    Science.gov (United States)

    Medvedev, Alexei E.; Buneeva, Olga A.; Kopylov, Arthur T.; Gnedenko, Oksana V.; Medvedeva, Marina V.; Kozin, Sergey A.; Ivanov, Alexis S.; Zgoda, Victor G.; Makarov, Alexander A.

    2014-01-01

    The amyloid-? peptide is considered as a key player in the development and progression of Alzheimer’s disease (AD). Although good evidence exists that amyloid-? accumulates inside cells, intracellular brain amyloid-binding proteins remain poorly characterized. Proteomic profiling of rat brain homogenates, performed in this study, resulted in identification of 89 individual intracellular amyloid-binding proteins, and approximately 25% of them were proteins that we had previously identified as specifically binding to isatin, an endogenous neuroprotector molecule. A significant proportion of the amyloid-binding proteins (more than 30%) are differentially expressed or altered/oxidatively modified in AD patients. Incubation of brain homogenates with 70 µM hydrogen peroxide significantly influenced the profile of amyloid-? binding proteins and 0.1 mM isatin decreased the number of identified amyloid-? binding proteins both in control and hydrogen peroxide treated brain homogenates. The effects of hydrogen peroxide and isatin have been confirmed in optical biosensor experiments with purified glyceraldehyde-3-phosphate dehydrogenase, one of the known crucial amyloid-? binding proteins (also identified in this study). Data obtained suggest that isatin protects crucial intracellular protein targets against amyloid binding, and possibly favors intracellular degradation of this protein via preventing formation of amyloid-? oligomers described in the literature for some isatin derivatives. PMID:25551598

  11. The effects of endogenous non-peptide molecule isatin and hydrogen peroxide on proteomic profiling of rat brain amyloid-? binding proteins: relevance to Alzheimer's disease?

    Science.gov (United States)

    Medvedev, Alexei E; Buneeva, Olga A; Kopylov, Arthur T; Gnedenko, Oksana V; Medvedeva, Marina V; Kozin, Sergey A; Ivanov, Alexis S; Zgoda, Victor G; Makarov, Alexander A

    2015-01-01

    The amyloid-? peptide is considered as a key player in the development and progression of Alzheimer's disease (AD). Although good evidence exists that amyloid-? accumulates inside cells, intracellular brain amyloid-binding proteins remain poorly characterized. Proteomic profiling of rat brain homogenates, performed in this study, resulted in identification of 89 individual intracellular amyloid-binding proteins, and approximately 25% of them were proteins that we had previously identified as specifically binding to isatin, an endogenous neuroprotector molecule. A significant proportion of the amyloid-binding proteins (more than 30%) are differentially expressed or altered/oxidatively modified in AD patients. Incubation of brain homogenates with 70 µM hydrogen peroxide significantly influenced the profile of amyloid-? binding proteins and 0.1 mM isatin decreased the number of identified amyloid-? binding proteins both in control and hydrogen peroxide treated brain homogenates. The effects of hydrogen peroxide and isatin have been confirmed in optical biosensor experiments with purified glyceraldehyde-3-phosphate dehydrogenase, one of the known crucial amyloid-? binding proteins (also identified in this study). Data obtained suggest that isatin protects crucial intracellular protein targets against amyloid binding, and possibly favors intracellular degradation of this protein via preventing formation of amyloid-? oligomers described in the literature for some isatin derivatives. PMID:25551598

  12. Brain amyloid ? protein and memory disruption in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Weiming Xia

    2010-09-01

    Full Text Available Weiming XiaCenter for Neurologic Diseases, Department of Neurology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USAAbstract: The development of amyloid-containing neuritic plaques is an invariable characteristic of Alzheimer’s diseases (AD. The conversion from monomeric amyloid ? protein (A? to oligomeric A? and finally neuritic plaques is highly dynamic. The specific Aß species that is correlated with disease severity remains to be discovered. Oligomeric A? has been detected in cultured cells, rodent and human brains, as well as human cerebrospinal fluid. Synthetic, cell, and brain derived A? oligomers have been found to inhibit hippocampal long-term potentiation (LTP and this effect can be suppressed by the blockage of A? oligomer formation. A large body of evidence suggests that A? oligomers inhibit N-methyl-D-aspartate receptor dependent LTP; additional receptors have also been found to elicit downstream pathways upon binding to A? oligomers. Amyloid antibodies and small molecular compounds that reduce brain A? levels and block A? oligomer formation are capable of reversing synaptic dysfunction and these approaches hold a promising therapeutic potential to rescue memory disruption.Keywords: Alzheimer, amyloid, oligomer, long-term potentiation, NMDA

  13. Automated solid-state NMR resonance assignment of protein microcrystals and amyloids

    International Nuclear Information System (INIS)

    Solid-state NMR is an emerging structure determination technique for crystalline and non-crystalline protein assemblies, e.g., amyloids. Resonance assignment constitutes the first and often very time-consuming step to a structure. We present ssFLYA, a generally applicable algorithm for automatic assignment of protein solid-state NMR spectra. Application to microcrystals of ubiquitin and the Ure2 prion C-terminal domain, as well as amyloids of HET-s(218–289) and ?-synuclein yielded 88–97 % correctness for the backbone and side-chain assignments that are classified as self-consistent by the algorithm, and 77–90 % correctness if also assignments classified as tentative by the algorithm are included

  14. Amyloid formation of native folded protein induced by peptide-based graft copolymer.

    Science.gov (United States)

    Koga, Tomoyuki; Taguchi, Kazuhiro; Kogiso, Masaki; Kobuke, Yoshiaki; Kinoshita, Takatoshi; Higuchi, Masahiro

    2002-11-01

    We report here that a native folded holo-myoglobin, when incubated with a synthetic amyloidogenic peptide in aqueous solutions, forms fibrils. These fibrils took a cross-beta form (inter-strand spacing: 4.65 A and inter-sheet spacing: 10.65 A) and bound the amyloidophilic dye Congo red as did the authentic amyloid fibrils. In contrast such fibril formation of myoglobin did not occur in the absence of the peptide. These results suggest the possibility that inter-molecular interaction of native protein with the amyloidogenic peptide trigger the amyloid formation even for the non-pathogenic native protein like myoglobin, which itself exists as a globular form, under certain conditions. PMID:12417301

  15. Automated solid-state NMR resonance assignment of protein microcrystals and amyloids

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Elena [Goethe University Frankfurt am Main, Center for Biomolecular Magnetic Resonance, Institute of Biophysical Chemistry (Germany); Gath, Julia [ETH Zurich, Physical Chemistry (Switzerland); Habenstein, Birgit [UMR 5086 CNRS/Universite de Lyon 1, Institut de Biologie et Chimie des Proteines (France); Ravotti, Francesco; Szekely, Kathrin; Huber, Matthias [ETH Zurich, Physical Chemistry (Switzerland); Buchner, Lena [Goethe University Frankfurt am Main, Center for Biomolecular Magnetic Resonance, Institute of Biophysical Chemistry (Germany); Boeckmann, Anja, E-mail: a.bockmann@ibcp.fr [UMR 5086 CNRS/Universite de Lyon 1, Institut de Biologie et Chimie des Proteines (France); Meier, Beat H., E-mail: beme@ethz.ch [ETH Zurich, Physical Chemistry (Switzerland); Guentert, Peter, E-mail: guentert@em.uni-frankfurt.de [Goethe University Frankfurt am Main, Center for Biomolecular Magnetic Resonance, Institute of Biophysical Chemistry (Germany)

    2013-07-15

    Solid-state NMR is an emerging structure determination technique for crystalline and non-crystalline protein assemblies, e.g., amyloids. Resonance assignment constitutes the first and often very time-consuming step to a structure. We present ssFLYA, a generally applicable algorithm for automatic assignment of protein solid-state NMR spectra. Application to microcrystals of ubiquitin and the Ure2 prion C-terminal domain, as well as amyloids of HET-s(218-289) and {alpha}-synuclein yielded 88-97 % correctness for the backbone and side-chain assignments that are classified as self-consistent by the algorithm, and 77-90 % correctness if also assignments classified as tentative by the algorithm are included.

  16. Biosensor based protein profiling on reverse phase serum microarray

    OpenAIRE

    Sjöberg, Ronald; Hammarström, L; Nilsson, Peter

    2012-01-01

    The reverse phase serum microarray format enables multi-parallel and simultaneous analysis of literally thousands of samples, a feature which is of uttermost importance for protein profiling of clinical samples. We have here screened 2400 serum samples for their potential IgA deficiency by using a fluorescence based reverse phase serum microarray platform and a biosensor based label-free microarray platform for verification and also compared our microarray-results to clinical routine ELISA. W...

  17. The Drosophila Homologue of the Amyloid Precursor Protein Is a Conserved Modulator of Wnt PCP Signaling

    OpenAIRE

    Soldano, Alessia; Okray, Zeynep; Janovska, Pavlina; Tmejová, Kate?ina; Reynaud, Elodie; Claeys, Annelies; Yan, Jiekun; Atak, Zeynep Kalender; De Strooper, Bart; Dura, Jean-Maurice; Bryja, Vít?zslav; Bassem A. Hassan

    2013-01-01

    Wnt Planar Cell Polarity (PCP) signaling is a universal regulator of polarity in epithelial cells, but it regulates axon outgrowth in neurons, suggesting the existence of axonal modulators of Wnt-PCP activity. The Amyloid precursor proteins (APPs) are intensely investigated because of their link to Alzheimer's disease (AD). APP's in vivo function in the brain and the mechanisms underlying it remain unclear and controversial. Drosophila possesses a single APP homologue called APP Like, or APPL...

  18. Amyloid-? protein dimers isolated directly from Alzheimer's brains impair synaptic plasticity and memory.

    OpenAIRE

    ROWAN, MICHAEL JOSEPH

    2008-01-01

    Alzheimer’s disease (AD) constitutes a rising threat to public health. Despite extensive research in cellular and animal models, identifying the pathogenic agent present in the human brain and showing that it confers key features of AD have not been achieved. We extracted soluble amyloid ?–protein (A?) oligomers directly from the cerebral cortex of typical AD subjects. The oligomers potently inhibited long term potentiation (LTP), enhanced long term depression (LTD), and reduced dendritic spi...

  19. Amyloid Precursor Protein and Alpha Synuclein Translation, Implications for Iron and Inflammation in Neurodegenerative diseases

    OpenAIRE

    Cahill, Catherine M; Lahiri, Debomoy K.; Huang, Xudong; Rogers, Jack T.

    2008-01-01

    Recent studies that alleles in the hemochromatosis gene may accelerate the onset of Alzheimer's disease (AD) by five years have validated interest in the model in which metals (particularly iron) accelerate disease course. Biochemical and biophysical measurements demonstrated the presence of elevated levels of neurotoxic copper, zinc and iron in the brains of AD patients. Intracellular levels of amyloid precursor protein (APP) holoprotein were shown to be modulated via iron by a mechanism tha...

  20. Membrane-mediated Amyloidogenesis and the Promotion of Oxidative Lipid Damage by Amyloid ? Proteins*S

    OpenAIRE

    Murray, Ian V. J.; Liu, Liu; Komatsu, Hiroaki; Uryu, Kunihiro; Xiao, Gang; Lawson, John A.; Axelsen, Paul H.

    2007-01-01

    Evidence of oxidative stress and the accumulation of fibrillar amyloid ? proteins (A?) in senile plaques throughout the cerebral cortex are consistent features in the pathology of Alzheimer disease. To define a mechanistic link between these two processes, various aspects of the relationship between oxidative lipid membrane damage and amyloidogenesis were characterized by chemical and physical techniques. Earlier studies of this relationship demonstrated that oxidatively damaged synthetic lip...

  1. Funktion des Amyloid Precursor Proteins und dessen Spaltprodukten bei der synaptischen Übertragung

    OpenAIRE

    Priller, Christina

    2006-01-01

    Das Amyloid Precursor Protein (APP) spielt eine wichtige Rolle in der Pathogenese der Alzheimer-Erkrankung. Seine physiologische Funktion in Neuronen, in denen es sich hauptsächlich in den Synapsen befindet, ist immer noch weitestgehend ungeklärt. Mit Hilfe autaptischer, hippocampaler Neurone von APP-Knockout-Mäusen, konnte gezeigt werden, dass Knockout-Neurone signifikant erhöhte Amplituden stimulierter AMPA- und NMDA-Rezeptor vermittelter exzitatorischer postsynaptischer Ströme (EPSC) au...

  2. Macroautophagy is not directly involved in the metabolism of amyloid precursor protein.

    OpenAIRE

    Boland, B.; Smith, DA; Mooney, D; Jung, SS; Walsh, DM; Platt, FM

    2010-01-01

    Alterations in the metabolism of amyloid precursor protein (APP) are believed to play a central role in Alzheimer disease pathogenesis. Burgeoning data indicate that APP is proteolytically processed in endosomal-autophagic-lysosomal compartments. In this study, we used both in vivo and in vitro paradigms to determine whether alterations in macroautophagy affect APP metabolism. Three mouse models of glycosphingolipid storage diseases, namely Niemann-Pick type C1, GM1 gangliosidosis, and Sandho...

  3. Deletion of Mint proteins decreases amyloid production in transgenic mouse models of Alzheimer’s disease

    OpenAIRE

    Ho, Angela; Liu, Xinran; Südhof, Thomas C.

    2008-01-01

    Mints/X11s are neuronal adaptor proteins that bind to amyloid-? precursor protein (APP). Previous studies suggested that Mint/X11 proteins influence APP cleavage, and affect production of pathogenic A?-peptides in Alzheimer’s disease; however, the biological significance of Mint/X11-binding to APP and their possible role in A?-production remain unclear. Here, we crossed conditional and constitutive Mint1, Mint2, and Mint3 knockout mice with transgenic mouse models of Alzheimer’s disease overp...

  4. Powerful beneficial effects of benfotiamine on cognitive impairment and beta-amyloid deposition in amyloid precursor protein/presenilin-1 transgenic mice.

    Science.gov (United States)

    Pan, Xiaoli; Gong, Neng; Zhao, Jing; Yu, Zhe; Gu, Fenghua; Chen, Jia; Sun, Xiaojing; Zhao, Lei; Yu, Meijing; Xu, Zhiru; Dong, Wenxin; Qin, Yan; Fei, Guoqiang; Zhong, Chunjiu; Xu, Tian-Le

    2010-05-01

    Reduction of glucose metabolism in brain is one of the main features of Alzheimer's disease. Thiamine (vitamin B1)-dependent processes are critical in glucose metabolism and have been found to be impaired in brains from patients with Alzheimer's disease. However, thiamine treatment exerts little beneficial effect in these patients. Here, we tested the effect of benfotiamine, a thiamine derivative with better bioavailability than thiamine, on cognitive impairment and pathology alterations in a mouse model of Alzheimer's disease, the amyloid precursor protein/presenilin-1 transgenic mouse. We show that after a chronic 8 week treatment, benfotiamine dose-dependently enhanced the spatial memory of amyloid precursor protein/presenilin-1 mice in the Morris water maze test. Furthermore, benfotiamine effectively reduced both amyloid plaque numbers and phosphorylated tau levels in cortical areas of the transgenic mice brains. Unexpectedly, these effects were not mimicked by another lipophilic thiamine derivative, fursultiamine, although both benfotiamine and fursultiamine were effective in increasing the levels of free thiamine in the brain. Most notably, benfotiamine, but not fursultiamine, significantly elevated the phosphorylation level of glycogen synthase kinase-3alpha and -3beta, and reduced their enzymatic activities in the amyloid precursor protein/presenilin-1 transgenic brain. Therefore, in the animal Alzheimer's disease model, benfotiamine appears to improve the cognitive function and reduce amyloid deposition via thiamine-independent mechanisms, which are likely to include the suppression of glycogen synthase kinase-3 activities. These results suggest that, unlike many other thiamine-related drugs, benfotiamine may be beneficial for clinical Alzheimer's disease treatment. PMID:20385653

  5. Genetic and environmental influences of surfactant protein D serum levels

    DEFF Research Database (Denmark)

    Sorensen, G.L.; Hjelmborg, J.V.; Kyvik, K.O.; Fenger, Mogens; Hoj, A.; Bendixen, C.; Sørensen, Thorkild I.A.; Holmskov, Uffe Laurits

    2006-01-01

    The collectin surfactant protein D (SP-D) is an important component of the pulmonary innate immune system, but SP-D is also present on extrapulmonary epithelial surfaces and in serum, where it has been used as a biomarker for pulmonary disease states. In this study, we investigate the mechanisms defining the constitutional serum level of SP-D and determine the magnitude of the genetic contribution to serum SP-D in the adult population. Recent studies have demonstrated that serum SP-D concentrati...

  6. Acute phase serum proteins in diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Rema M

    1996-01-01

    Full Text Available The serum concentration of various acute phase reactants were studied in patients with non-insulin dependent diabetes mellitus with and without retinopathy and in control subjects. The serum levels of haptoglobin was elevated in diabetics with retinopathy and the levels were highest in those with proliferative diabetic retinopathy. The levels of serum albumin, alpha-1 acid glycoprotein, alpha-1 antitrypsin and caeruloplasmin were not significantly different between the patients with retinopathy and controls. Haptoglobin increases serum viscosity and this could be the mechanism by which it plays a role in pathogenesis of diabetic retinopathy. These preliminary observations need to be confirmed by studies based on larger number of patients. Longitudinal studies on acute phase reactants in various stages of development of diabetic retinopathy would also provide valuable information.

  7. FKBP12 regulates the localization and processing of amyloid precursor protein in human cell lines

    Indian Academy of Sciences (India)

    Fan-Lun Liu; Ting-Yi Liu; Fan-Lu Kung

    2014-03-01

    One of the pathological hallmarks of Alzheimer’s disease is the presence of insoluble extracellular amyloid plaques. These plaques are mainly constituted of amyloid beta peptide (A), a proteolytic product of amyloid precursor protein (APP). APP processing also generates the APP intracellular domain (AICD). We have previously demonstrated that AICD interacts with FKBP12, a peptidyl-prolyl cis-trans isomerase (PPIase) ubiquitous in nerve systems. This interaction was interfered by FK506, a clinically used immunosuppressant that has recently been reported to be neuroprotective. To elucidate the roles of FKBP12 in the pathogenesis of Alzheimer’s disease, the effect of FKBP12 overexpression on APP processing was evaluated. Our results revealed that APP processing was shifted towards the amyloidogenic pathway, accompanied by a change in the subcellular localization of APP, upon FKBP12 overexpression. This FKBP12-overexpression-induced effect was reverted by FK506. These findings support our hypothesis that FKBP12 may participate in the regulation of APP processing. FKBP12 overexpression may lead to the stabilization of a certain isomer (presumably the cis form) of the Thr668-Pro669 peptide bond in AICD, therefore change its affinity to flotillin-1 or other raft-associated proteins, and eventually change the localization pattern and cause a shift in the proteolytic processing of APP.

  8. Focally Elevated Creatine Detected in Amyloid Precursor Protein (APP) Transgenic Mice and Alzheimer Disease Brain Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Gallant,M.; Rak, M.; Szeghalmi, A.; Del Bigio, M.; Westaway, D.; Yang, J.; Julian, R.; Gough, K.

    2006-01-01

    The creatine/phosphocreatine system, regulated by creatine kinase, plays an important role in maintaining energy balance in the brain. Energy metabolism and the function of creatine kinase are known to be affected in Alzheimer diseased brain and in cells exposed to the {beta}-amyloid peptide. We used infrared microspectroscopy to examine hippocampal, cortical, and caudal tissue from 21-89-week-old transgenic mice expressing doubly mutant (K670N/M671L and V717F) amyloid precursor protein and displaying robust pathology from an early age. Microcrystalline deposits of creatine, suggestive of perturbed energetic status, were detected by infrared microspectroscopy in all animals with advanced plaque pathology. Relatively large creatine deposits were also found in hippocampal sections from post-mortem Alzheimer diseased human brain, compared with hippocampus from non-demented brain. We therefore speculate that this molecule is a marker of the disease process.

  9. Oligomerization preceding amyloid fibril formation: a process in common to intrinsically disordered and globular proteins.

    Science.gov (United States)

    Zerovnik, Eva

    2011-01-01

    Neurodegenerative diseases present a big burden to society. At the molecular level many of them - if not all - show protein aggregation (as an epiphenomenon or as a cause). The knowledge on details of thermodynamics and kinetics as well as structure of the protein aggregates, especially the early and soluble oligomers, may help in designing inhibitors for early stages of such diseases. Here, a possible outlook on more general mechanism for their formation is discussed. The oligomers of amyloid forming proteins, which are present prior and during nucleation and amyloid fibril formation, are claimed to be toxic to cells. Oligomers of the globular proteins and the intrinsically disordered proteins (IDPs), form in vitro upon partial denaturation and renaturation, respectively. Often they form if the sample is heated or freeze-thawed for a few cycles. A question is asked if this does not highlight one important property in common to globular proteins and IDPs, namely, a high energetic barrier dividing such oligomers from the monomers. This also would imply existence of two populations of states, one, the monomer - being metastable - at least under the conditions, which promote fibril formation. PMID:22149676

  10. Correlation between some hematological parameters, acute phase proteins and serum immunoglobulins in experimental caprine besnoitiosis.

    Science.gov (United States)

    Hosseini, A; Namazi, F; Oryan, A; Nazifi, S

    2015-06-01

    The present study was undertaken to investigate correlation between some hematological parameters, acute phase proteins and immunoglobulins in the experimentally infected goats with Besnoitia caprae from the time of infection till 360 days post infection (DPI). Six male goats, approximately 12-16 months old, were inoculated subcutaneously with approximately 1.3 × 10(8) bradyzoites of B. caprae and blood samples were collected at weekly intervals from the jugular vein of the goats. Total leukocyte count and differential leukocyte counts were determined. Acute phase proteins (APPs) including serum amyloid A (SAA), haptoglobin (Hp), fibrinogen and ceruloplasmin were undertaken at weekly intervals. We evaluated an enzyme-linked immunosorbent assay (ELISA) (using a somatic antigen of bradyzoite) to detect anti-B. caprae antibodies in caprine sera. Cysts were present in the skin biopsies of the distal parts of the leg of the infected goats from 28 DPI. From 30 to 360 DPI, results showed that the APPs concentrations including SAA, Hp, fibrinogen and ceruloplasmin were enhanced in the serum of infected goats. However, there were some variation in hematological parameters; the differences were not significant with those of the normal values. Some variations were seen in the levels of specific antibodies against this parasite and they had correlation with some hematological parameters and acute-phase proteins. PMID:26063991

  11. Homodimerization Protects the Amyloid Precursor Protein C99 Fragment from Cleavage by ?-Secretase.

    Science.gov (United States)

    Winkler, Edith; Julius, Ayse; Steiner, Harald; Langosch, Dieter

    2015-10-13

    The amyloid precursor protein (APP) is a single-span integral membrane protein whose C-terminal fragment C99 is cleaved within the transmembrane helix by ?-secretase. Cleavage produces various A? peptides that are linked to the etiology of Alzheimer's disease. The transmembrane helix is known to homodimerize in a sequence-specific manner, and considerable controversy about whether the homodimeric form of C99 is cleaved by ?-secretase exists. Here, we generated various covalent C99 homodimers via cross-linking at engineered cysteine residues. None of the homodimers was cleaved in vitro by purified ?-secretase, strongly suggesting that homodimerization protects C99 from cleavage. PMID:26403946

  12. Protein-induced Photophysical Changes to the Amyloid Indicator Dye Thioflavin T

    Energy Technology Data Exchange (ETDEWEB)

    L Wolfe; M Calabrese; A Nath; D Blaho; A Miranker; Y Xiong

    2011-12-31

    The small molecule thioflavin T (ThT) is a defining probe for the identification and mechanistic study of amyloid fiber formation. As such, ThT is fundamental to investigations of serious diseases such as Alzheimer's disease, Parkinson disease, and type II diabetes. For each disease, a different protein undergoes conformational conversion to a {beta}-sheet rich fiber. The fluorescence of ThT exhibits an increase in quantum yield upon binding these fibers. Despite its widespread use, the structural basis for binding specificity and for the changes to the photophysical properties of ThT remain poorly understood. Here, we report the co-crystal structures of ThT with two alternative states of {beta}-2 microglobulin ({beta}2m); one monomeric, the other an amyloid-like oligomer. In the latter, the dye intercalates between {beta}-sheets orthogonal to the {beta}-strands. Importantly, the fluorophore is bound in such a manner that a photophysically relevant torsion is limited to a range of angles generally associated with low, not high, quantum yield. Quantum mechanical assessment of the fluorophore shows the electronic distribution to be strongly stabilized by aromatic interactions with the protein. Monomeric {beta}2m gives little increase in ThT fluorescence despite showing three fluorophores, at two binding sites, in configurations generally associated with high quantum yield. Our efforts fundamentally extend existing understanding about the origins of amyloid-induced photophysical changes. Specifically, the {beta}-sheet interface that characterizes amyloid acts both sterically and electronically to stabilize the fluorophore's ground state electronic distribution. By preventing the fluorophore from adopting its preferred excited state configuration, nonradiative relaxation pathways are minimized and quantum yield is increased.

  13. Serum amyloid A stimulates macrophage foam cell formation via lectin-like oxidized low-density lipoprotein receptor 1 upregulation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ha Young, E-mail: hayoung@skku.edu [Department of Biological Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Kim, Sang Doo [Department of Biological Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Baek, Suk-Hwan [Department of Biochemistry and Molecular Biology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Choi, Joon Hyuk [Department of Pathology, College of Medicine, Yeungnam University, Daegu 705-717 (Korea, Republic of); Cho, Kyung-Hyun [School of Biotechnology, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Zabel, Brian A. [Palo Alto Institute for Research and Education, Veterans Affairs Hospital, Palo Alto, CA 94304 (United States); Bae, Yoe-Sik, E-mail: yoesik@skku.edu [Department of Biological Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Mitochondria Hub Regulation Center, Dong-A University, Busan 602-714 (Korea, Republic of); Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of)

    2013-03-29

    Highlights: ? SAA induced macrophage foam cell formation. ? SAA stimulated upregulation of lectin-like oxidized low-density lipoprotein receptor 1 (LOX1). ? SAA-induced LOX1 expression and foam cell formation is mediated by JNK/NF-?B signaling. ? HDL-conjugated SAA also stimulates foam cell formation via LOX1 upregulation. ? The finding reveals a novel mechanism of action of SAA in the pathogenesis of atherosclerosis. -- Abstract: Elevated levels of serum amyloid A (SAA) is a risk factor for cardiovascular diseases, however, the role of SAA in the pathophysiology of atherosclerosis remains unclear. Here we show that SAA induced macrophage foam cell formation. SAA-stimulated foam cell formation was mediated by c-jun N-terminal kinase (JNK) signaling. Moreover, both SAA and SAA-conjugated high density lipoprotein stimulated the expression of the important scavenger receptor lectin-like oxidized low-density lipoprotein receptor 1 (LOX1) via nuclear factor-?B (NF-?B). A LOX1 antagonist carrageenan significantly blocked SAA-induced foam cell formation, indicating that SAA promotes foam cell formation via LOX1 expression. Our findings therefore suggest that SAA stimulates foam cell formation via LOX1 induction, and thus likely contributes to atherogenesis.

  14. Serum amyloid A stimulates macrophage foam cell formation via lectin-like oxidized low-density lipoprotein receptor 1 upregulation

    International Nuclear Information System (INIS)

    Highlights: ? SAA induced macrophage foam cell formation. ? SAA stimulated upregulation of lectin-like oxidized low-density lipoprotein receptor 1 (LOX1). ? SAA-induced LOX1 expression and foam cell formation is mediated by JNK/NF-?B signaling. ? HDL-conjugated SAA also stimulates foam cell formation via LOX1 upregulation. ? The finding reveals a novel mechanism of action of SAA in the pathogenesis of atherosclerosis. -- Abstract: Elevated levels of serum amyloid A (SAA) is a risk factor for cardiovascular diseases, however, the role of SAA in the pathophysiology of atherosclerosis remains unclear. Here we show that SAA induced macrophage foam cell formation. SAA-stimulated foam cell formation was mediated by c-jun N-terminal kinase (JNK) signaling. Moreover, both SAA and SAA-conjugated high density lipoprotein stimulated the expression of the important scavenger receptor lectin-like oxidized low-density lipoprotein receptor 1 (LOX1) via nuclear factor-?B (NF-?B). A LOX1 antagonist carrageenan significantly blocked SAA-induced foam cell formation, indicating that SAA promotes foam cell formation via LOX1 expression. Our findings therefore suggest that SAA stimulates foam cell formation via LOX1 induction, and thus likely contributes to atherogenesis

  15. Role of sequence and membrane composition in structure of transmembrane domain of Amyloid Precursor Protein

    Science.gov (United States)

    Straub, John

    2013-03-01

    Aggregation of proteins of known sequence is linked to a variety of neurodegenerative disorders. The amyloid ? (A ?) protein associated with Alzheimer's Disease (AD) is derived from cleavage of the 99 amino acid C-terminal fragment of Amyloid Precursor Protein (APP-C99) by ?-secretase. Certain familial mutations of APP-C99 have been shown to lead to altered production of A ? protein and the early onset of AD. We describe simulation studies exploring the structure of APP-C99 in micelle and membrane environments. Our studies explore how changes in sequence and membrane composition influence (1) the structure of monomeric APP-C99 and (2) APP-C99 homodimer structure and stability. Comparison of simulation results with recent NMR studies of APP-C99 monomers and dimers in micelle and bicelle environments provide insight into how critical aspects of APP-C99 structure and dimerization correlate with secretase processing, an essential component of the A ? protein aggregation pathway and AD.

  16. Calpain Activation Promotes BACE1 Expression, Amyloid Precursor Protein Processing, and Amyloid Plaque Formation in a Transgenic Mouse Model of Alzheimer Disease*

    OpenAIRE

    Liang, Bin; Duan, Bao-Yu; Zhou, Xiu-Ping; Gong, Jia-Xin; Luo, Zhen-Ge

    2010-01-01

    Abnormal activation of calpain is implicated in synaptic dysfunction and participates in neuronal death in Alzheimer disease (AD) and other neurological disorders. Pharmacological inhibition of calpain has been shown to improve memory and synaptic transmission in the mouse model of AD. However, the role and mechanism of calpain in AD progression remain elusive. Here we demonstrate a role of calpain in the neuropathology in amyloid precursor protein (APP) and presenilin 1 (PS1) double-transgen...

  17. Sphingolipid storage affects autophagic metabolism of the amyloid precursor protein and promotes Abeta generation.

    Science.gov (United States)

    Tamboli, Irfan Y; Hampel, Heike; Tien, Nguyen T; Tolksdorf, Karen; Breiden, Bernadette; Mathews, Paul M; Saftig, Paul; Sandhoff, Konrad; Walter, Jochen

    2011-02-01

    Deposition of amyloid ? peptides (A?s) in extracellular amyloid plaques within the human brain is a hallmark of Alzheimer's disease (AD). A? derives from proteolytic processing of the amyloid precursor protein (APP) by ?- and ?-secretases. The initial cleavage by ?-secretase results in shedding of the APP ectodomain and generation of APP C-terminal fragments (APP-CTFs), which can then be further processed within the transmembrane domain by ?-secretase, resulting in release of A?. Here, we demonstrate that accumulation of sphingolipids (SLs), as occurs in lysosomal lipid storage disorders (LSDs), decreases the lysosome-dependent degradation of APP-CTFs and stimulates ?-secretase activity. Together, this results in increased generation of both intracellular and secreted A?. Notably, primary fibroblasts from patients with different SL storage diseases show strong accumulation of potentially amyloidogenic APP-CTFs. By using biochemical, cell biological, and genetic approaches, we demonstrate that SL accumulation affects autophagic flux and impairs the clearance of APP-CTFs. Thus, accumulation of SLs might not only underlie the pathogenesis of LSDs, but also trigger increased generation of A? and contribute to neurodegeneration in sporadic AD. PMID:21289194

  18. The binding of americium and curium to human serum proteins

    International Nuclear Information System (INIS)

    Human serum labelled with americium or curium has been separated by affinity chromatography. The results indicate that the only protein binding these actinides is transferrin, not albumin. Similar experiments with rat serum gave poor resolution of transferrin and albumin, due to the lower affinity of rat albumin for the Blue Sepharose. The reason for the low recoveries of radioactivity during the chromatographic process was investigated. Dissociation of the protein-actinide complex followed by competition between the gell matrix and the protein for the actinide was suspected to be responsible. Results showed that for both labelled human and rat serum, the proportion of americium eluting in the protein fractions decreased with the flow rate, confirming the suspicions of dissociation. (U.K.)

  19. Structural and Thermodynamic Characteristics That Seed Aggregation of Amyloid-? Protein in Water.

    Science.gov (United States)

    Chong, Song-Ho; Park, Mirae; Ham, Sihyun

    2012-02-14

    Amyloid-? (A?) proteins undergo conformational transitions leading to aggregation-prone structures, which can initiate self-assembly to form soluble oligomers and eventually insoluble amyloid fibrils when transferred from the transmembrane phase to the physiological aqueous phase. Yet, how A? proteins acquire an aggregation-prone nature during the conformational transitions in water remains elusive. Here, we investigate key structural and thermodynamic features of a 42-residue A? (A?42) protein that seed aggregation based on the fully atomistic, explicit-water molecular dynamics simulations as well as on the integral-equation theory of liquids for solvation thermodynamic analysis. We performed a structure-based analysis on the solvation free energy, a major determinant of the protein hydrophobicity/solubility that influences the aggregation propensity of A?42 protein in water. In addition, the Gibbs free energy and its constituents including protein internal energy, protein configurational entropy, solvation enthalpy, and solvation entropy were computed to elucidate thermodynamic driving forces for the conformational transitions of A?42 protein in water. On the basis of the atomic-decomposition analysis of these thermodynamic functions, we demonstrate how N-terminal (residues 1-11) and C-terminal (39-42) regions as well as the central region (16-18) contribute significantly to decreasing the solubility of A?42 protein upon its conformational transitions in water. These results are consistent with the recent experimental and computational implications and further provide the molecular origin for why the C terminus may serve as an "internal seed" for aggregation and the N-terminal segment may act as a "catalyst" in inducing the A?42 self-assembly. This work takes a step forward toward the identification of structural and thermodynamic features of the A?42 monomer that seed the aggregation process in water. PMID:26596619

  20. Systematic study of plasma and serum proteins in the pig

    International Nuclear Information System (INIS)

    This work has been carried out in the framework of the determination of the physiological constants of a normal pig. The aim was to study the serum and plasma proteins of this animal species, the ultimate object being to discover whether the qualitative and quantitative changes in these proteins can make a significant contribution to the establishment of a biological dosimetry for irradiated pigs. The serum and plasma from a normal pig were analyzed first by various simple electrophoretic methods and then by immuno-electrophoresis. As a result of the particular characteristics of pig serum we have gradually been led to make numerous modifications to the techniques used for human serums or for those of small laboratory animals. Much careful work and patience were required in order to obtain reproducible results. (authors)

  1. Serum C-reactive protein in dairy herds

    OpenAIRE

    Lee, Wen-Chuan; Hsiao, Huo-Cheng; Wu, Ying-Ling; Lin, Jyh-Hung; Lee, Yen-Pai; Fung, Hang-Poung; Chen, Hsin-Hsin; Chen, Yu-Hsin; Chu, Rea-Min

    2003-01-01

    The purpose of this study was to determine the relationship between the serum level of C-reactive protein (CRP) and lactation and health status. Blood samples were collected every 2 wk for 12 mo from 29 randomly selected dairy cattle on 3 farms. At the time the blood samples were collected, the stage of pregnancy, lactation status, breeding records, general health condition, reproductive status, and body condition score were recorded for each cow. Serum CRP was detected with sodium dodecyl su...

  2. [Serum levels of immunosuppressive acidic protein in gynecological cancer].

    Science.gov (United States)

    Sato, S; Wakisaka, T; Hamazaki, Y; Oikawa, N; Toki, T; Yamauchi, R; Sakahira, H; Tase, T; Yajima, A; Suzuki, M

    1983-07-01

    The pre-therapy serum levels of immunosuppressive acidic protein (IAP) were assayed in patients with cancer of the uterine cervix and ovarium using the single radial immunodiffusion method. These levels were normal in patients with early cancer of uterine cervix (O and Ia stage); in advanced cancer patients they were increased with cancer stage. The serum IAP levels in ovarian cancer were higher than in patients with advanced uterine cervical cancer. PMID:6887522

  3. Serum Protein Electrophoresis in Dogs With Intestinal Parasites

    OpenAIRE

    KAYMAZ, Alev AKDO?AN; BAKIREL, Utku; Remzi GÖNÜL; Tan, Hüseyin

    1999-01-01

    The serum of 66 dogs with intestinal parasites (showing gastrointestinal problems caused by taeniosis, coccidiosis, ancylostomosis, trichuriosis and ascarididosis) was examined by electrophoresis. There were 6 dogs with coccidiosis, 6 dogs with ancylostomosis, 6 dogs with trichuriosis, 24 dogs with taeniosis and 24 dogs with ascarididosis. After agar gel protein electorphoresis of the serum samples, ?1 globulin levels were significantly lower in the coccidiosis group than in the other grou...

  4. Serum Copper and Plasma Protein Status in Normal Pregnancy

    Directory of Open Access Journals (Sweden)

    Nushrat Noor, Nasim Jahan, Nayma Sultana

    2012-12-01

    Full Text Available AbstractBackground: Gradual alteration of serum copper and some plasma protein levels may occur with advancement of pregnancy, which is associated with increased maternal and infant morbidity and mortality.Objective: To observe serum copper and plasma protein levels in normal pregnant women of different trimesters in order to find out their nutritional status.Methods: This cross sectional study was carried out in the Department of Physiology, Sir Salimullah Medical College (SSMC, Dhaka, between 1st January 2010 and December 2010. Ninety normal pregnant women of different trimesters with age 20-30 years were included in the study group. They were selected from Out Patient Department of Obstetrics and Gynaecology, SSMC. Age matched 30 non-pregnant women were taken as control. Serum copper level was measured by Spectrophotometric method, serum total protein and albumin levels were estimated by standard method. Statistical analysis was done by one way ANOVA, Bonferroni and Pearson’s correlation coefficient test as applicable.Results: Serum Cu levels were significantly higher in all trimesters of pregnant women compared to control. Again, this value was significantly higher in 3rd trimester than that of in 1st and 2nd trimester and also in 2nd trimester than that of in 1st trimester. In addition, mean serum total protein level was significantly lower in 3rd trimester than control but no statistically significant difference was observed among different trimesters. Again, mean serum albumin level was significantly lower in 2nd and 3rd trimester than 1st trimester and control. In addition, serum Cu concentration showed significant positive correlation with different trimesters of gestation.Conclusion: This study reveals that hypercupremia along with hypoproteinemia occur in pregnant women from 1st to 3rd trimester of gestation. This gradual alteration of micro and macronutrients become more profound with advancement of pregnancy.

  5. Endolysosome involvement in HIV-1 transactivator protein-induced neuronal amyloid beta production.

    Science.gov (United States)

    Chen, Xuesong; Hui, Liang; Geiger, Nicholas H; Haughey, Norman J; Geiger, Jonathan D

    2013-10-01

    The increased life expectancy of people living with HIV-1/AIDS is accompanied by increased prevalence of HIV-1-associated neurocognitive disorder. As well, these individuals are increasingly experiencing Alzheimer's disease (AD)-like neurocognitive problems and neuropathological features such as increased deposition of amyloid beta (A?) protein. Findings that A? production occurs largely in endolysosomes, that HIV-1 transactivator protein (Tat) disrupts endolysosome function-an early pathological feature of AD-and that HIV-1 Tat can increase A? levels prompted us to test the hypothesis that endolysosome dysfunction is associated with HIV-1 Tat-induced increases in neuronal A? generation. Using primary cultured rat hippocampal neurons, we found that treatment with HIV-1 Tat caused such morphological changes as enlargement of endolysosomes identified with LysoTracker dye and such functional changes as elevated endolysosome pH measured ratiometrically with LysoSensor dye. The HIV-1 Tat-induced changes in endolysosome function preceded temporally HIV-1 Tat-induced increases in A? generation measured using enzyme-linked immunosorbent assay. In addition, we demonstrated that HIV-1 Tat increased endolysosome accumulation of A? precursor protein and A? identified using immunostaining with 4G8 antibodies. Furthermore, we demonstrated that treatment of neurons with HIV-1 Tat increased endolysosome accumulation of beta amyloid-converting enzyme, the rate-limiting enzymatic step for A? production, and enhanced beta amyloid-converting enzyme activity. Together, our findings suggest that HIV-1 Tat increases neuronal A? generation and thereby contributes to the development of AD-like pathology in HIV-1-infected individuals by disturbing endolysosome structure and function. PMID:23673310

  6. Formaldehyde at Low Concentration Induces Protein Tau into Globular Amyloid-Like Aggregates In Vitro and In Vivo

    Science.gov (United States)

    Nie, Chun Lai; Wei, Yan; Chen, Xinyong; Liu, Yan Ying; Dui, Wen; Liu, Ying; Davies, Martyn C.; Tendler, Saul J.B.; He, Rong Giao

    2007-01-01

    Recent studies have shown that neurodegeneration is closely related to misfolding and aggregation of neuronal tau. Our previous results show that neuronal tau aggregates in formaldehyde solution and that aggregated tau induces apoptosis of SH-SY5Y and hippocampal cells. In the present study, based on atomic force microscopy (AFM) observation, we have found that formaldehyde at low concentrations induces tau polymerization whilst acetaldehyde does not. Neuronal tau misfolds and aggregates into globular-like polymers in 0.01–0.1% formaldehyde solutions. Apart from globular-like aggregation, no fibril-like polymerization was observed when the protein was incubated with formaldehyde for 15 days. SDS-PAGE results also exhibit tau polymerizing in the presence of formaldehyde. Under the same experimental conditions, polymerization of bovine serum albumin (BSA) or ?-synuclein was not markedly detected. Kinetic study shows that tau significantly misfolds and polymerizes in 60 minutes in 0.1% formaldehyde solution. However, presence of 10% methanol prevents protein tau from polymerization. This suggests that formaldehyde polymerization is involved in tau aggregation. Such aggregation process is probably linked to the tau's special “worm-like” structure, which leaves the ?-amino groups of Lys and thiol groups of Cys exposed to the exterior. Such a structure can easily bond to formaldehyde molecules in vitro and in vivo. Polymerizing of formaldehyde itself results in aggregation of protein tau. Immunocytochemistry and thioflavin S staining of both endogenous and exogenous tau in the presence of formaldehyde at low concentrations in the cell culture have shown that formaldehyde can induce tau into amyloid-like aggregates in vivo during apoptosis. The significant protein tau aggregation induced by formaldehyde and the severe toxicity of the aggregated tau to neural cells may suggest that toxicity of methanol and formaldehyde ingestion is related to tau misfolding and aggregation. PMID:17637844

  7. Amyloid Precursor Protein Regulates Brain Apolipoprotein E and Cholesterol Metabolism through Lipoprotein Receptor LRP1

    OpenAIRE

    Qiang LIU; Zerbinatti, Celina V; ZHANG Juan; Hoe, Hyang-Sook; Wang, Baiping; Cole, Sarah L.; Herz, Joachim; Muglia, Louis; Bu, Guojun

    2007-01-01

    Mutations in the amyloid precursor protein (APP) cause early-onset Alzheimer's disease (AD), but the only genetic risk factor for late-onset AD is the ?4 allele of apolipoprotein E (apoE), a major cholesterol carrier. Using Cre-lox conditional knockout mice, we demonstrate that lipoprotein receptor LRP1 expression regulates apoE and cholesterol levels within the CNS. We also found that deletion of APP and its homologue APLP2, or components of the ?-secretase complex, significantly enhanced th...

  8. Segregation of a missense mutation in the amyloid precursor protein gene with familial Alzheimer's disease.

    OpenAIRE

    Goate, A; Chartier-Harlin, MC; Mullan, M; Brown, J.; Crawford, F.; Fidani, L; Giuffra, L; Haynes, A.; IRVING, N; James, L.

    1991-01-01

    A locus segregating with familial Alzheimer's disease (AD) has been mapped to chromosome 21, close to the amyloid precursor protein (APP) gene. Recombinants between the APP gene and the AD locus have been reported which seemed to exclude it as the site of the mutation causing familial AD. But recent genetic analysis of a large number of AD families has demonstrated that the disease is heterogeneous. Families with late-onset AD do not show linkage to chromosome 21 markers. Some families with e...

  9. Mechanism of cytotoxicity mediated by the C31 fragment of the Amyloid Precursor Protein

    OpenAIRE

    Park, Sun Ah; Shaked, Gideon M.; Bredesen, Dale E; Koo, Edward H.

    2009-01-01

    The cytoplasmic tail of the amyloid precursor protein (APP) contains two putatively cytotoxic peptides, Jcasp and C31, derived by caspase cleavage of APP. Jcasp is a fragment starting from the ?-secretase site to position 664, while C31 is a fragment from position 665 to the C-terminus. Our studies now showed that compared to C31, Jcasp appeared to play a minor role in cytotoxicity. In particular, inhibition of Jcasp generation by treatment of ?-secretase inhibitor did not lead to any attenua...

  10. Analysis of glycans on serum proteins using antibody microarrays

    OpenAIRE

    Chen, Songming; Haab, Brian B.

    2009-01-01

    Antibody arrays can be employed for the profiling glycan structures on proteins. Antibody arrays capture multiple, specific proteins directly from biological samples (such as serum), and lectin and glycan-binding antibodies probe the levels of specific glycans on the captured proteins. We use a practical method of partitioning microscope slides to enable the convenient processing of many detection reagents or samples. A critical first step in the procedure is the chemical derivatization of th...

  11. Expression of active secreted forms of human amyloid beta-protein precursor by recombinant baculovirus-infected insect cells.

    OpenAIRE

    Bhasin, R; Nostrand, W.E. Van; Saitoh, T; Donets, M A; Barnes, E.A.; Quitschke, W W; Goldgaber, D

    1991-01-01

    Three alternatively spliced forms of the amyloid precursor protein (APP), APP-695, APP-751, and APP-770, were expressed in the baculovirus expression vector system. The recombinant proteins were secreted into the culture medium by infected insect cells, and APP molecules were detected in insect cells and medium 2 days after infection with the recombinant APP-baculoviruses. A partial sequence of the NH2 terminus of the secreted protein revealed identity with the native secreted protein and sho...

  12. Analyzing Ensembles of Amyloid Proteins Using Bayesian Statistics.

    Science.gov (United States)

    Gurry, Thomas; Fisher, Charles K; Schmidt, Molly; Stultz, Collin M

    2016-01-01

    Intrinsically disordered proteins (IDPs) are notoriously difficult to study experimentally because they rapidly interconvert between many dissimilar conformations during their biological lifetime, and therefore cannot be described by a single structure. The importance of studying these systems, however, is underscored by the fact that they form toxic aggregates that play a role in the pathogenesis of many disorders. The first step towards a comprehensive understanding of the aggregation mechanism of these proteins involves a description of their thermally accessible states under physiologic conditions. The resulting conformational ensembles correspond to coarse-grained descriptions of their energy landscapes, where the number of structures in the ensemble is related to the resolution in which one views the free energy surface. Here, we provide step-by-step instructions on how to use experimental data to construct a conformational ensemble for an IDP using a Variational Bayesian Weighting (VBW) algorithm. We further discuss how to leverage this Bayesian approach to identify statistically significant ensemble-wide observations that can form the basis of further experimental studies. PMID:26453218

  13. Production of glycosylated soluble amyloid precursor protein alpha (sAPPalpha) in Leishmania tarentolae.

    Science.gov (United States)

    Klatt, Stephan; Rohe, Michael; Alagesan, Kathirvel; Kolarich, Daniel; Konthur, Zoltán; Hartl, Daniela

    2013-01-01

    Soluble amyloid precursor protein alpha (sAPPalpha) is a cleavage product of the amyloid precursor protein (APP), the etiologic agent in Alzheimer's disease (AD). Reduced expression of sAPPalpha was previously found in the brains of AD patients, and it was suggested that sAPPalpha might counteract neurotoxic effects of Abeta, another APP cleavage product with enhanced abundance in Alzheimer's diseased brains. However, little is known about the biological functions of sAPPalpha. Thus, efficient production of this protein is a prerequisite for further studies. The unicellular eukaryotic parasite Leishmania tarentolae has recently emerged as a promising expression system for eukaryotic proteins due to its ability to posttranslationally modify proteins combined with easy cultivation and high protein yield. Interestingly, sAPPalpha produced in L. tarentolae was biologically active and glycosylated. In contrast to nonglycosylated sAPPalpha expressed in Eschericha coli, it also featured higher stability against enzymatic degradation. Detailed analysis of the glycosylation pattern of sAPPalpha produced in L. tarentolae by PGC-LC-ESI-MS/MS N-glycan analysis identified among eukaryotic species the highly conserved core pentasaccharide (Man3GlcNAc2) as being attached to Asn467 of sAPPalpha. Using oxonium ion scanning of CID-MS/MS spectra in combination with ETD fragmentation, we also identified two peptides (peptides 269-288 and 575-587) modified with N-acetyl hexosamine (HexNAc) residues. One of these O-glycosylation sites could be unambiguously assigned to Thr576 of sAPPalpha. This is the first time that O-glycosylation of a recombinant protein expressed in L. tarentolae has been demonstrated. Together, human sAPPalpha produced in L. tarentolae was N- and O-glycosylated on similar sites as described for mammalian-expressed sAPPalpha and showed similar biological activity. This demonstrates that L. tarentolae is a very suitable and simple to handle expression system for mammalian glycoproteins. PMID:23214446

  14. Evaluation of serum amyloid A and haptoglobin concentrations as prognostic indicators for horses with inflammatory disease examined at a tertiary care hospital.

    Science.gov (United States)

    Westerman, Trina L; Tornquist, Susan J; Foster, Crystal M; Poulsen, Keith P

    2015-10-01

    OBJECTIVE To evaluate use of serum amyloid A (SAA) and haptoglobin concentrations as prognostic indicators for horses with inflammatory disease in regard to euthanasia, complications, and hospitalization duration and cost. ANIMALS 20 clinically normal horses and 53 horses with inflammatory disease. PROCEDURES Total WBC count, neutrophil count, and fibrinogen, SAA, and haptoglobin concentrations were determined for clinically normal horses and horses with suspected inflammatory disease. Clinicopathologic values at admission were compared to test the use of SAA and haptoglobin concentrations in predicting euthanasia, complications, and hospitalization duration and cost. Haptoglobin and SAA concentrations of 22 horses were monitored during hospitalization to test the use of serial measurements in predicting survival and complications. RESULTS Neutrophil count and SAA and haptoglobin concentrations were significantly different at admission for horses with inflammatory disease, compared with those for clinically normal horses. Horses with colitis and peritonitis had significantly higher SAA and haptoglobin concentrations than clinically normal horses. A moderate positive correlation (r = 0.355) between hospitalization duration and haptoglobin concentration was identified. Horses with an increase in SAA concentration between 24 and 72 hours after admission, compared with admission SAA concentration, were significantly more likely (OR, 7.0; 95% confidence interval, 1.1 to 45.9) to be euthanized or develop complications. CONCLUSIONS AND CLINICAL RELEVANCE Concentrations of SAA and haptoglobin at admission were not significantly correlated with outcome in horses with inflammatory conditions. Acute-phase proteins likely have more utility in serial analysis rather than testing at a single time point for horses with inflammatory conditions. PMID:26413826

  15. Structure of beta-crystallite assemblies formed by Alzheimer beta-amyloid protein analogues: analysis by x-ray diffraction.

    OpenAIRE

    Inouye, H.; Fraser, P E; Kirschner, D. A.

    1993-01-01

    To elucidate the relation between amyloid fibril formation in Alzheimer disease and the primary structure of the beta/A4 protein, which is the major component of the amyloid, we have been investigating the ability of peptides sharing sequences with beta/A4 to form fibrils in vitro. In previous studies we focused on the macroscopic morphology of the assemblies formed by synthetic peptides corresponding in sequence to different regions of this protein. In the present study we analyze the x-ray ...

  16. Localization and Trafficking of Amyloid-? Protein Precursor and Secretases: Impact on Alzheimer's Disease.

    Science.gov (United States)

    Agostinho, Paula; Pliássova, Anna; Oliveira, Catarina R; Cunha, Rodrigo A

    2015-01-01

    Alzheimer's disease (AD) affects almost 35 million people worldwide. One of the neuropathological features of AD is the presence of extracellular amyloid plaques, which are mainly composed of amyloid-? (A?) peptides. These peptides derive from the amyloidogenic proteolytic processing of the amyloid-? protein precursor (A?PP), through the sequential action of ?- and ?-secretases. However, A?PP can also be cleaved by a non-amyloidogenic pathway, involving an ?-secretase, and in this case the A? formation is precluded. The production of A? and of other A?PP catabolites depends on the spatial and temporal co-localization of A?PP with ?- or ?-secretases and ?-secretase, which traffic through the secretory pathway in a highly regulated manner. Disturbances on A?PP and secretases intracellular trafficking and, consequently, in their localization may affect dynamic interactions between these proteins with consequences in the AD pathogenesis. In this article, we critically review the recent knowledge about the trafficking and co-localization of A?PP and related secretases in the brain under physiological and AD conditions. A particular focus is given to data concerning the distribution of A?PP and secretases in different types of synapses relatively to other neuronal or glial localizations. Furthermore, we discuss some possible signals that govern the dynamic encounter of A?PP with each group of secretases, such as A?PP mutations, estrogen deprivation, chronic stress, metabolic impairment, and alterations in sleep pattern-associated with aging. The knowledge of key signals that are responsible for the shifting of A?PP processing away from ?-secretases and toward the ?-secretases might be useful to develop AD therapeutic strategies. PMID:25589722

  17. Serum amyloid A (SAA) as a biomarker of chronic infection due to boat strike trauma in a free-ranging Florida manatee (Trichechus manatus latirostris) with incidental polycystic kidneys.

    Science.gov (United States)

    Harr, Kendal E; Rember, Renee; Ginn, Pamela E; Lightsey, Jessica; Keller, Martha; Reid, James; Bonde, Robert K

    2011-10-01

    Watercraft-related trauma is the predominant cause of human-induced mortality in manatees (Trichechus manatus latirostris), a federal- and state-listed endangered species. Pyothorax (documented in this case report) and other secondary infections are common sequelae of inhalation of water and the open wounds caused by boat propellers. These secondary infections can lead to the demise of the animal weeks to months after the traumatic incident when external wounds have healed. Diagnosis of underlying disease on physical examination during capture and restraint can be difficult. Acute phase proteins, including serum amyloid A, fibrinogen, and albumin can be used to diagnose inflammatory disease in manatees and improve quality of medical care and husbandry. We also provide the first report of polycystic kidneys in Sirenians. PMID:22102678

  18. Serum amyloid A (SAA) as a biomarker of chronic infection due to boat strike trauma in a free-ranging Florida manatee (Trichechus manatus latirostris) with incidental polycystic kidneys

    Science.gov (United States)

    Harr, Kendal E.; Rember, Renee; Ginn, Pamela E.; Lightsey, Jessica; Keller, Martha; Reid, James; Bonde, Robert K.

    2011-01-01

    Watercraft-related trauma is the predominant cause of human-induced mortality in manatees (Trichechus manatus latirostris), a federal- and state-listed endangered species. Pyothorax (documented in this case report) and other secondary infections are common sequelae of inhalation of water and the open wounds caused by boat propellers. These secondary infections can lead to the demise of the animal weeks to months after the traumatic incident when external wounds have healed. Diagnosis of underlying disease on physical examination during capture and restraint can be difficult. Acute phase proteins, including serum amyloid A, fibrinogen, and albumin can be used to diagnose inflammatory disease in manatees and improve quality of medical care and husbandry. We also provide the first report of polycystic kidneys in Sirenians.

  19. Protein binding and serum bactericidal activities of vancomycin and teicoplanin.

    OpenAIRE

    Dykhuizen, R S; Harvey, G.; Stephenson, N.; Nathwani, D.; Gould, I. M.

    1995-01-01

    In a randomized crossover study, the protein binding and serum bactericidal activities (SBAs) of vancomycin and teicoplanin against Staphylococcus aureus and Streptococcus pyogenes were investigated in six healthy volunteers. Total concentrations in serum 1 h postadministration of vancomycin and teicoplanin were 25.5 +/- 2.7 and 10.8 +/- 8.9 mg/liter, respectively; mean free concentrations were 14.6 +/- 2.0 and 0.6 +/- 0.9 mg/liter, respectively. Protein binding for vancomycin was 36.9% +/- 2...

  20. Alpha-1-antitrypsin studies: canine serum and canine surfactant protein

    International Nuclear Information System (INIS)

    Canine serum alpha-1-antitrypsin was isolated by gel filtration and affinity chromatography and characterized by polyacrylamide gel electrophoresis and immunoelectrophoresis. Measurement of the trypsin inhibitory capacity of the separated protein indicated a ninefold concentration of functional trypsin inhibitor during the isolation procedure. Electrophoresis demonstrated the presence of a single protein with alpha-globulin mobility and a molecular weight near that of human alpha-1-antitrypsin. The trypsin inhibitory capacity of pulmonary surfactant protein from five Beagle dogs was measured, related to total surfactant protein concentration, and compared with similar measurements on whole serum from the same animals. Results indicated a variable concentration of trypsin inhibitor in the canine pulmonary surfactant protein. However, the concentration in the surfactant protein was always significantly higher than that in the corresponding serum sample. Preliminary experiments designed to separate the trypsin inhibitory fraction(s) from the other surfactant proteins by gel filtration chromatography indicated that the trypsin inhibitor was probably a single protein with a molecular weight near that of alpha-1-antitrypsin. (U.S.)

  1. Unraveling the mysteries of serum albumin—more than just a serum protein

    OpenAIRE

    Merlot, Angelica M.; Kalinowski, Danuta S.; Richardson, Des R.

    2014-01-01

    Serum albumin is a multi-functional protein that is able to bind and transport numerous endogenous and exogenous compounds. The development of albumin drug carriers is gaining increasing importance in the targeted delivery of cancer therapy, particularly as a result of the market approval of the paclitaxel-loaded albumin nanoparticle, Abraxane®. Considering this, there is renewed interest in isolating and characterizing albumin-binding proteins or receptors on the plasma membrane that are res...

  2. Immunoglobulin light chains, glycosaminoglycans and amyloid.

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, F. J.; Kisilevsky, R.; Biosciences Division; Queen' s Univ.

    2000-03-01

    Immunoglobulin light chains are the precursor proteins for fibrils that are formed during primary amyloidosis and in amyloidosis associated with multiple myeloma. As found for the approximately 20 currently described forms of focal, localized, or systemic amyloidoses, light chain-related fibrils extracted from physiological deposits are invariably associated with glycosaminoglycans, predominantly heparan sulfate. Other amyloid-related proteins are either structurally normal, such as g2-microglobulin and islet amyloid polypeptide, fragments of normal proteins such as serum amyloid A protein or the precursor protein of the g peptide involved in Alzheimer's disease, or are inherited forms of single amino acid variants of a normal protein such as found in the familial forms of amyloid associated with transthyretin. In contrast, the primary structures of light chains involved in fibril formation exhibit extensive mutational diversity rendering some proteins highly amyloidogenic and others non-pathological. The interactions between light chains and glycosaminoglycans are also affected by amino acid variation and may influence the clinical course of disease by enhancing fibril stability and contributing to resistance to protease degradation. Relatively little is currently known about the mechanisms by which glycosaminoglycans interact with light chains and light-chain fibrils. It is probable that future studies of this uniquely diverse family of proteins will continue o shed light on the processes of amyloidosis, and contribute as well to a greater understanding of the normal physiological roles of glycosaminoglycans.

  3. Amyloid-clearing proteins and their epigenetic regulation as a therapeutic target in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Natalia N Nalivaeva

    2014-09-01

    Full Text Available Abnormal elevation of amyloid ?-peptide (A? levels in the brain is the primary trigger for neuronal cell death specific to Alzheimer’s disease (AD. It is now evident that A? levels in the brain are manipulable due to a dynamic equilibrium between its production from the amyloid precursor protein (APP and removal by amyloid clearance proteins. Clearance can be either enzymic or non-enzymic (binding/transport proteins. Intriguingly several of the main amyloid-degrading enzymes (ADEs are members of the M13 peptidase family (neprilysin (NEP, NEP2 and the endothelin converting enzymes (ECE-1 and -2. A distinct metallopeptidase, insulin-degrading enzyme (IDE, also contributes to A? degradation in the brain. The ADE family currently embraces more than 20 members, both membrane-bound and soluble, and of differing cellular locations. NEP plays an important role in brain function terminating neuropeptide signals. Its decrease in specific brain areas with age or after hypoxia, ischaemia or stroke contribute significantly to the development of AD pathology. The recently discovered mechanism of epigenetic regulation of NEP (and other genes by the APP intracellular domain (AICD and its dependence on the cell type and APP isoform expression suggest possibilities for selective manipulation of NEP gene expression in neuronal cells. We have also observed that another amyloid-clearing protein, namely transthyretin (TTR, is also regulated in the neuronal cell by a mechanism similar to NEP. Dependence of amyloid clearance proteins on histone deacetylases and the ability of HDAC inhibitors to up-regulate their expression in the brain opens new avenues for developing preventive strategies in AD.

  4. Amyloid-clearing proteins and their epigenetic regulation as a therapeutic target in Alzheimer’s disease

    Science.gov (United States)

    Nalivaeva, Natalia N.; Belyaev, Nikolai D.; Kerridge, Caroline; Turner, Anthony J.

    2014-01-01

    Abnormal elevation of amyloid ?-peptide (A?) levels in the brain is the primary trigger for neuronal cell death specific to Alzheimer’s disease (AD). It is now evident that A? levels in the brain are manipulable due to a dynamic equilibrium between its production from the amyloid precursor protein (APP) and removal by amyloid clearance proteins. Clearance can be either enzymic or non-enzymic (binding/transport proteins). Intriguingly several of the main amyloid-degrading enzymes (ADEs) are members of the M13 peptidase family (neprilysin (NEP), NEP2 and the endothelin converting enzymes (ECE-1 and -2)). A distinct metallopeptidase, insulin-degrading enzyme (IDE), also contributes to A? degradation in the brain. The ADE family currently embraces more than 20 members, both membrane-bound and soluble, and of differing cellular locations. NEP plays an important role in brain function terminating neuropeptide signals. Its decrease in specific brain areas with age or after hypoxia, ischaemia or stroke contribute significantly to the development of AD pathology. The recently discovered mechanism of epigenetic regulation of NEP (and other genes) by the APP intracellular domain (AICD) and its dependence on the cell type and APP isoform expression suggest possibilities for selective manipulation of NEP gene expression in neuronal cells. We have also observed that another amyloid-clearing protein, namely transthyretin (TTR), is also regulated in the neuronal cell by a mechanism similar to NEP. Dependence of amyloid clearance proteins on histone deacetylases and the ability of HDAC inhibitors to up-regulate their expression in the brain opens new avenues for developing preventive strategies in AD. PMID:25278875

  5. AMP-activated Protein Kinase Signaling Activation by Resveratrol Modulates Amyloid-? Peptide Metabolism*

    Science.gov (United States)

    Vingtdeux, Valérie; Giliberto, Luca; Zhao, Haitian; Chandakkar, Pallavi; Wu, Qingli; Simon, James E.; Janle, Elsa M.; Lobo, Jessica; Ferruzzi, Mario G.; Davies, Peter; Marambaud, Philippe

    2010-01-01

    Alzheimer disease is an age-related neurodegenerative disorder characterized by amyloid-? (A?) peptide deposition into cerebral amyloid plaques. The natural polyphenol resveratrol promotes anti-aging pathways via the activation of several metabolic sensors, including the AMP-activated protein kinase (AMPK). Resveratrol also lowers A? levels in cell lines; however, the underlying mechanism responsible for this effect is largely unknown. Moreover, the bioavailability of resveratrol in the brain remains uncertain. Here we show that AMPK signaling controls A? metabolism and mediates the anti-amyloidogenic effect of resveratrol in non-neuronal and neuronal cells, including in mouse primary neurons. Resveratrol increased cytosolic calcium levels and promoted AMPK activation by the calcium/calmodulin-dependent protein kinase kinase-?. Direct pharmacological and genetic activation of AMPK lowered extracellular A? accumulation, whereas AMPK inhibition reduced the effect of resveratrol on A? levels. Furthermore, resveratrol inhibited the AMPK target mTOR (mammalian target of rapamycin) to trigger autophagy and lysosomal degradation of A?. Finally, orally administered resveratrol in mice was detected in the brain where it activated AMPK and reduced cerebral A? levels and deposition in the cortex. These data suggest that resveratrol and pharmacological activation of AMPK have therapeutic potential against Alzheimer disease. PMID:20080969

  6. Mechanism of amyloid ?-protein dimerization determined using single-molecule AFM force spectroscopy

    Science.gov (United States)

    Lv, Zhengjian; Roychaudhuri, Robin; Condron, Margaret M.; Teplow, David B.; Lyubchenko, Yuri L.

    2013-10-01

    A?42 and A?40 are the two primary alloforms of human amyloid ?-protein (A?). The two additional C-terminal residues of A?42 result in elevated neurotoxicity compared with A?40, but the molecular mechanism underlying this effect remains unclear. Here, we used single-molecule force microscopy to characterize interpeptide interactions for A?42 and A?40 and corresponding mutants. We discovered a dramatic difference in the interaction patterns of A?42 and A?40 monomers within dimers. Although the sequence difference between the two peptides is at the C-termini, the N-terminal segment plays a key role in the peptide interaction in the dimers. This is an unexpected finding as N-terminal was considered as disordered segment with no effect on the A? peptide aggregation. These novel properties of A? proteins suggests that the stabilization of N-terminal interactions is a switch in redirecting of amyloids form the neurotoxic aggregation pathway, opening a novel avenue for the disease preventions and treatments.

  7. Studies on serum protein level in patients with hepatic cirrhosis

    Directory of Open Access Journals (Sweden)

    Anca-Mirela Amariei

    2012-03-01

    Full Text Available The liver synthesizes besides its structural proteins, most of the plasma proteins: albumin, 2-globulin-ceruloplasmin, and -lipoproteins, and a good part of protein coagulation factors (prothrombin, proconvertin, proaccelerin, fibrinogen. After the study of the serum proteins in patients with liver cirrhosis from Botosani County Hospital Mavromati were found decreases in albumin content both women and men installed, probably due to the imbalance between synthesis and the degradation processes, and the -globulins increased values compared with thereference range.

  8. Blood serum components and serum protein test of Hybro-PG broilers of different ages

    Directory of Open Access Journals (Sweden)

    PRL Silva

    2007-12-01

    Full Text Available Blood serum samples of HYBRO PG broilers were analyzed, with 30 samples collected from 21-day-old broilers (G1, 30 from 35-day-old birds (G2, and 30 from 42-day-old birds (G3, with the aim of establishing normal values of some blood serum parameters. The activities of the enzymes gamma-glutamyl-transferase (GGT, aspartate aminotransferase (AST, creatine kinase (CK, alkaline phosphatase (ALP, and lactate dehydrogenase (LDH, serum levels of total calcium, calcium ion, phosphorus, sodium, potassium, magnesium, chlorides, creatinine, uric acid, triglycerides, cholesterol, total protein, albumin, total and indirect and direct bilirubin, and electrophoretic profile of serum proteins in acrylamide (SDS-PAGE and agarose gel were determined. There was no influence of age on total bilirubin and albumin levels. All the other evaluated parameters presented differences in at least one age group. Protein electrophoretic profile also changed as a function of age. The obtained results can be considered as normal for the studied ages, and therefore be used as references for the interpretation of laboratory exams of broilers of this genetic line in the evaluated ages.

  9. Acute-phase proteins and serum immunoglobulins in ankylosing spondylitis.

    OpenAIRE

    Laurent, M R; Panayi, G S

    1983-01-01

    The erythrocyte sedimentation rate (ESR) and the serum acute-phase proteins (APP), C-reactive protein (CRP), fibrinogen, 9th component of complement (C9), and alpha, antitrypsin were measured on 231 occasions in 80 patients with ankylosing spondylitis and compared with those in 30 controls. APP levels did not correlate with clinical assessment of disease activity. However, there were significant correlations between CRP, C9, and fibrinogen (p = less than 0.01), suggesting that these APP may b...

  10. Changes in serum protein profiles of chickens with tibial dyschondroplasia

    Science.gov (United States)

    Differences in serum protein profiles were analyzed to identify biomarkers associated with a poultry leg problem named tibial dyschondroplasia (TD) that can cause lameness. We used a bead-based affinity matrix containing a combinatorial library of hexapeptides (ProteoMinerTM) to deplete high abundan...

  11. EFFECTS OF THYROIDECTOMY ON THE SERUM PROTEIN FRACTIONS IN DOG

    Directory of Open Access Journals (Sweden)

    N. Guiti

    1969-01-01

    Full Text Available The study on the serum protein electrophoresis following thyroidectomy in A puppies showed a significant decrease in the albumin and -a-ratio associated with a relative increase in gamma and total globulin, but alterations of alpha I and beta globulin were not statistically charcteristic in our thyroidectomized dogs.

  12. Aggregation and fibrillation of bovine serum albumin

    DEFF Research Database (Denmark)

    Holm, NK; Jespersen, SK; Thomassen, LV; Wolff, TY; Sehgal, P; Thomsen, LA; Christiansen, Gunna; Andersen, CB; Knudsen, AD; Otzen, DE

    2007-01-01

    The all-alpha helix multi-domain protein bovine serum albumin (BSA) aggregates at elevated temperatures. Here we show that these thermal aggregates have amyloid properties. They bind the fibril-specific dyes Thioflavin T and Congo Red, show elongated although somewhat worm-like morphology and characteristic amyloid X-ray fiber diffraction peaks. Fibrillation occurs over minutes to hours without a lag phase, is independent of seeding and shows only moderate concentration dependence, suggesting in...

  13. Measurement of ?- and ?-secretase cleaved amyloid precursor protein in cerebrospinal fluid from Alzheimer patients

    DEFF Research Database (Denmark)

    Sjögren, Magnus; Andreasen, Niels

    2003-01-01

    One of the major histopathological hallmarks of Alzheimer's disease (AD) is redundant senile plaques mainly composed of ?-amyloid (A?) aggregates. Alternative cleavage of the amyloid precursor protein (APP), occurring in both normal and AD subjects, results in the generation and secretion of soluble APP (sAPP) and A?. We examined the cerebrospinal fluid (CSF) for ?- and ?-secretase cleaved sAPP (?-sAPP and ?-sAPP) in 81 sporadic AD patients, 19 patients with mild cognitive impairment, and 42 healthy controls by using newly developed sandwich enzyme-linked immunosorbent assay methods. We found that neither the level of CSF-?-sAPP nor CSF-?-sAPP differed between sporadic AD patients and healthy controls. These findings further support the conclusion that there is no change in APP expression in sporadic AD. However, the level of CSF-?-sAPP was significantly increased in patients with mild cognitive impairment compared to controls. We also investigated the relationship between the CSF level of ?/?-sAPP and A?42 and the apoE ?4 (apoE4) allele. Significantly lower levels of CSF-?-sAPP were found in AD patients possessing one or two apoE4 alleles than in those not possessing the apoE4 allele. Neither the levels of CSF-?-sAPP nor CSF-A?42 differed when comparing ApoE4 allele-positive with allele-negative individuals. © 2003 Elsevier Science (USA). All rights reserved.

  14. Beta-secretase-cleaved amyloid precursor protein in Alzheimer brain: a morphologic study

    DEFF Research Database (Denmark)

    Sennvik, Kristina; Bogdanovic, N

    2004-01-01

    beta-amyloid (Abeta) is the main constituent of senile plaques seen in Alzheimer's disease. Abeta is derived from the amyloid precursor protein (APP) via proteolytic cleavage by proteases beta- and gamma-secretase. In this study, we examined content and localization of beta-secretase-cleaved APP (beta-sAPP) in brain tissue sections from the frontal, temporal and occipital lobe. Strong granular beta-sAPP staining was found throughout the gray matter of all three areas, while white matter staining was considerably weaker. beta-sAPP was found to be localized in astrocytes and in axons. We found the beta-sAPP immunostaining to be stronger and more extensive in gray matter in Alzheimer disease (AD) cases than controls. The axonal beta-sAPP staining was patchy and unevenly distributed for the AD cases, indicating impaired axonal transport. beta-sAPP was also found surrounding senile plaques and cerebral blood vessels. The results presented here show altered beta-sAPP staining in the AD brain, suggestive of abnormalprocessing and transport of APP.

  15. Sortilin and SorLA Display Distinct Roles in Processing and Trafficking of Amyloid Precursor Protein

    DEFF Research Database (Denmark)

    Gustafsen, Camilla; Glerup, Simon

    2013-01-01

    The development and progression of Alzheimer's disease is linked to excessive production of toxic amyloid-? peptide, initiated by ?-secretase cleavage of the amyloid precursor protein (APP). In contrast, soluble APP? (sAPP?) generated by the ?-secretase is known to stimulate dendritic branching and enhance synaptic function. Regulation of APP processing, and the shift from neurotrophic to neurotoxic APP metabolism remains poorly understood, but the cellular localization of APP and its interaction with various receptors is considered important. We here identify sortilin as a novel APP interaction partner. Like the related APP receptor SorLA, sortilin is highly expressed in the CNS, but whereas SorLA mainly colocalizes with APP in the soma, sortilin interacts with APP in neurites. The presence of sortilin promotes ?-secretase cleavage of APP, unlike SorLA, which inhibits the generation of all soluble products. Also, sortilin and SorLA both bind and mediate internalization of sAPP but to different cellular compartments. The interaction involves the 6A domain of APP, present in both neuronal and non-neuronal APP isoforms. This is important as sAPP receptors described so far only bind the non-neuronal isoforms, leaving SorLA and sortilin as the only receptors for sAPP generated by neurons. Together, our findings establish sortilin, as a novel APP interaction partner that influences both production and cellular uptake of sAPP.

  16. Delta-secretase cleaves amyloid precursor protein and regulates the pathogenesis in Alzheimer's disease.

    Science.gov (United States)

    Zhang, Zhentao; Song, Mingke; Liu, Xia; Su Kang, Seong; Duong, Duc M; Seyfried, Nicholas T; Cao, Xuebing; Cheng, Liming; Sun, Yi E; Ping Yu, Shan; Jia, Jianping; Levey, Allan I; Ye, Keqiang

    2015-01-01

    The age-dependent deposition of amyloid-? peptides, derived from amyloid precursor protein (APP), is a neuropathological hallmark of Alzheimer's disease (AD). Despite age being the greatest risk factor for AD, the molecular mechanisms linking ageing to APP processing are unknown. Here we show that asparagine endopeptidase (AEP), a pH-controlled cysteine proteinase, is activated during ageing and mediates APP proteolytic processing. AEP cleaves APP at N373 and N585 residues, selectively influencing the amyloidogenic fragmentation of APP. AEP is activated in normal mice in an age-dependent manner, and is strongly activated in 5XFAD transgenic mouse model and human AD brains. Deletion of AEP from 5XFAD or APP/PS1 mice decreases senile plaque formation, ameliorates synapse loss, elevates long-term potentiation and protects memory. Blockade of APP cleavage by AEP in mice alleviates pathological and behavioural deficits. Thus, AEP acts as a ?-secretase, contributing to the age-dependent pathogenic mechanisms in AD. PMID:26549211

  17. Serum proteins, trace metals and phosphatases in psoriasis

    Directory of Open Access Journals (Sweden)

    Bhatnagar M

    1994-01-01

    Full Text Available Serum proteins, zinc, copper, acid phosphatase (AcPase and alkaline phosphatase (AlPase were studied in both active and remission phases of psoriasis. Data were compared with healthy controls, ?1, ? and ? globulins were high in active phase while ?1 and ? globulins were at par in remission phase. Serum copper was low but zinc and alkaline phosphatase were significantly high in both active and remission phases of the disease. Acid phosphatase level was at par in all the experimental groups. Study suggests a positive correlation of globulin, zinc and Alpase in active and remission phase of psoriasis.

  18. Early and rapid de novo synthesis of Alzheimer beta A4-amyloid precursor protein (APP) in activated microglia.

    Science.gov (United States)

    Banati, R B; Gehrmann, J; Czech, C; Mönning, U; Jones, L L; König, G; Beyreuther, K; Kreutzberg, G W

    1993-11-01

    Upon acute activation, microglia, the immuneffector cells of the brain parenchyma, express the amyloid precursor protein (APP) that is otherwise prominent in pathological structures related to Alzheimer's disease. In this disease complex amyloid-bearing neuritic plaques contain beta A4-amyloid protein, the APP, and numerous inflammatory proteins. The accompanying activation of microglia has mostly been viewed as a secondary reaction to amyloid deposits. Activation of microglia was performed in a graded fashion. Transection of peripheral nerves such as the facial or sciatic nerve causes a microglial reaction within hours in the nucleus of origin or in projection areas of the CNS. A predominantly glial up-regulation of APP mRNA and protein could be detected as early as 6 h post lesion not only at the site of affected neuronal cell bodies but also in corresponding projection areas. Its time course suggests rapid transneuronal signalling to glial cells in the projection area. Light and electron microscopy demonstrate that microglia, which are cells of mononuclear phagocyte lineage and comprise up to 20% of all glial cells, are the dominant source for non-neuronal APP expression. Ultrastructurally, brain perivascular cells within the basal lamina constitutively express APP and thus are a possible source of vascular amyloid. Additionally, microglia express leukocyte-derived (L)-APP mRNA and protein that have recently been described in mononuclear cells of the immune system. Increased L-APP expression may serve as a potential marker for glial/microglial activation. Such immune-mediated amyloidogenesis initiated by microglia might have implications for the treatment of neurodegenerative diseases. PMID:7507467

  19. Acute phase proteins in bovine milk in an experimental model of Staphylococcus aureus subclinical mastitis

    DEFF Research Database (Denmark)

    Eckersall, P D; Young, F J; Nolan, A M; Knight, Christopher Harold; McComb, C; Waterston, M M; Hogarth, C J; Scott, E M; Fitzpatrick, J L

    2006-01-01

    The objectives were to establish the origin of 2 acute phase proteins in milk during subclinical bovine mastitis and to characterize the relationship between those proteins in milk and blood. Haptoglobin (Hp) and mammary-associated serum amyloid A (M-SAA3) appear in milk during mastitis, whereas Hp and serum amyloid A increase in serum during mastitis. The concentrations of these proteins were determined in an experimental model using a field strain of Staphylococcus aureus to induce subclinical...

  20. {sup 99m}Tc-MAMA-chrysamine G, a probe for beta-amyloid protein of Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Dezutter, N.A.; Groot, T.J. de; Bormans, G.M. [K.U. Leuven (Belgium). Lab. of Radiopharmaceutical Chemistry; Dom, R.J. [Department of Neuropathology, University Hospital Gasthuisberg, Leuven (Belgium); Verbruggen, A.M. [K.U. Leuven (Belgium). Lab. of Radiopharmaceutical Chemistry; U.Z. Gasthuisberg, Radiopharmacy, Leuven (Belgium)

    1999-11-01

    Chrysamine G (CG), an analogue of Congo red, is known to bind in vitro to the {beta}-amyloid protein (A{beta} 10-43) and to homogenates of several regions of the brain of Alzheimer's disease (AD) patients. We synthesised a conjugate of 2-(acetamido)-CG with a bis-S-trityl protected monoamide-monoaminedithiol (MAMA-Tr{sub 2}) tetraligand, which was efficiently deprotected and labelled with a 75% yield with technetium-99m, to obtain {sup 99m}Tc-MAMA-CG. In mice, {sup 99m}Tc-MAMA-CG was cleared mainly by the hepatobiliary system, resulting in a fast blood clearance. Brain uptake of {sup 99m}Tc-MAMA-CG was low. Co-injection with the blood pool tracer iodine-125 human serum albumin ({sup 125}I-HSA) demonstrated a brain/blood activity ratio for {sup 99m}Tc-MAMA-CG that was significantly higher than that for {sup 125}I-HSA (t test for dependent samples, P<0.02), indicating the ability of {sup 99m}Tc-MAMA-CG to cross the blood-brain barrier. In vitro autoradiography demonstrated pronounced binding of {sup 99m}Tc-MAMA-CG to {beta}-amyloid deposits in autopsy sections of the parietal and occipital cortex of an AD patient as compared with controls. Adding 10 {mu}M Congo red during incubation displaced the binding of {sup 99m}Tc-MAMA-CG. Congo red staining and autoradiography identified the same lesions. {sup 99m}Tc-MAMA-CG seems to bind selectively to {beta}-amyloid deposition in human brain parenchyma and blood vessels in vitro and thus might be a lead compound for further development of a useful tracer agent for the in vivo diagnosis of Alzheimer's disease. (orig.)

  1. Enhanced generation of Alzheimer's amyloid-? following chronic exposure to phorbol ester correlates with differential effects on alpha and epsilon isozymes of protein kinase C

    OpenAIRE

    da Cruz e Silva, Odete A. B.; Rebelo, Sandra; Vieira, Sandra I; Gandy, Sam; da Cruz e Silva, Edgar F; Greengard, Paul

    2008-01-01

    Alzheimer's amyloid precursor protein (APP) sorting and processing are modulated through signal transduction mechanisms regulated by protein phosphorylation. Notably, protein kinase C (PKC) appears to be an important component in signaling pathways that control APP metabolism. PKCs exist in at least 11 conventional and unconventional isoforms, and PKC? and PKC? isoforms have been specifically implicated in controlling the generation of soluble APP and amyloid-? (A?) fragments of APP, although...

  2. Amyloid in endomyocardial biopsies.

    Science.gov (United States)

    Kieninger, Barbara; Eriksson, Magdalena; Kandolf, Reinhard; Schnabel, Philipp A; Schönland, Stefan; Kristen, Arnt V; Hegenbart, Ute; Lohse, Peter; Röcken, Christoph

    2010-05-01

    The prognosis of cardiac amyloidosis depends on the nature and origin of the amyloid protein deposited. However, little is known about the prevalence and origin of amyloid in heart muscle biopsies. We therefore examined retrospectively the distribution and origin of amyloid in a consecutive series of endomyocardial biopsies. Endomyocardial biopsies with verified presence of amyloid from 101 patients were included. Amyloid was classified immunohistochemically in each of them. Our collective comprised 63 men and 38 women, with a mean age of 66 years (range 37-85 years). Cardiac amyloidosis was the most common of the AL (54 patients) or ATTR type (42 patients). In five individuals, amyloid remained unclassified. AL amyloidosis was subdivided into ALlambda (45 patients) and ALkappa amyloid (nine patients). AA amyloid was not found in any individual. The amount of amyloid was higher in AL than in ATTR amyloidosis. Genomic DNA was extracted and examined by DNA sequencing in 19 patients with ATTR amyloidosis. Five (26%) individuals carried TTR mutations (p.Val20Ile, p.Val30Met (twice), p.Asp39Val and p.Glu54Asp) and were classified as suffering from hereditary ATTR amyloidosis. Amyloid in endomyocardial biopsies is most commonly of immunoglobulin light chain origin, followed by non-hereditary and hereditary-type ATTR amyloid. PMID:20376481

  3. Serum protein concentrations in calves with experimentally induced pneumonic pasteurellosis

    Directory of Open Access Journals (Sweden)

    Fagliari J.J.

    2003-01-01

    Full Text Available Ten healthy 2 to 4-week-old Holstein calves were randomly allotted into control and infected groups. Control calves (n=5 were inoculated intrabronchially with 5ml of Dulbecco's phosphate-buffered saline solution (DPBSS. Infected calves (n=5 were inoculated intrabronchially with 5x10(9 log-phase Mannheimia haemolytica organisms suspended in 5ml of DPBSS. Blood samples were obtained 15 minutes before and one, two, four and six hours after inoculation. Serum protein concentrations were determined by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Serum concentrations of proteins with molecular weights of 125,000 D (ceruloplasmin, 60,000 D (a 1-antitrypsin, 45,000 D (haptoglobin, and 40,000 D (acid glycoprotein were significantly increased in calves with pneumonic pasteurellosis, compared with concentrations in control calves. Results indicate that acute phase proteins increase more rapidly after the onset of inflammation than previously thought. Measurement of serum protein concentrations may be useful in monitoring the progression of the induced pneumonic pasteurellosis in calves.

  4. Oxidative stress induces macroautophagy of amyloid beta-protein and ensuing apoptosis

    DEFF Research Database (Denmark)

    Zheng, Lin; Kågedal, Katarina

    2009-01-01

    There is increasing evidence for the toxicity of intracellular amyloid beta-protein (Abeta) to neurons and the involvement of lysosomes in this process in Alzheimer disease (AD). We have recently shown that oxidative stress, a recognized determinant of AD, enhances macroautophagy and leads to intralysosomal accumulation of Abeta in cultured neuroblastoma cells. We hypothesized that oxidative stress promotes AD by stimulating macroautophagy of Abeta that further may induce cell death by destabilizing lysosomal membranes. To investigate such possibility, we compared the effects of hyperoxia (40% ambient oxygen) in cultured HEK293 cells that were transfected with an empty vector (Vector), wild-type APP (APPwt), or Swedish mutant APP (APPswe). Exposure to hyperoxia for 5 days increased the number of cells with Abeta-containing lysosomes, as well as the number of apoptotic cells, compared to normoxic conditions. The rate of apoptosis in all three cell lines demonstrated dependence on intralysosomal Abeta content (Vector

  5. Amine oxidase activity of ?-amyloid precursor protein modulates systemic and local catecholamine levels.

    Science.gov (United States)

    Duce, J A; Ayton, S; Miller, A A; Tsatsanis, A; Lam, L Q; Leone, L; Corbin, J E; Butzkueven, H; Kilpatrick, T J; Rogers, J T; Barnham, K J; Finkelstein, D I; Bush, A I

    2013-02-01

    The catecholamines dopamine (DA), norepinephrine (NE) and epinephrine (E) are neurotransmitters and hormones that mediate stress responses in tissues and plasma. The expression of ?-amyloid precursor protein (APP) is responsive to stress and is high in tissues rich in catecholamines. We recently reported that APP is a ferroxidase, subsuming, in neurons and other cells, the iron-export activity that ceruloplasmin mediates in glia. Here we report that, like ceruloplasmin, APP also oxidizes synthetic amines and catecholamines catalytically (K(m) NE=0.27?mM), through a site encompassing its ferroxidase motif and selectively inhibited by zinc. Accordingly, APP knockout mice have significantly higher levels of DA, NE and E in brain, plasma and select tissues. Consistent with this, these animals have increased resting heart rate and systolic blood pressure as well as suppressed prolactin and lymphocyte levels. These findings support a role for APP in extracellular catecholaminergic clearance. PMID:22212595

  6. Amyloid Precursor Protein Translation Is Regulated by a 3’UTR Guanine Quadruplex

    Science.gov (United States)

    Sharoni, Michal; Olson, Kalee; Sebastian, Neeraj P.; Ansaloni, Sara; Schweitzer-Stenner, Reinhard; Akins, Michael R.; Bevilacqua, Philip C.; Saunders, Aleister J.

    2015-01-01

    A central event in Alzheimer’s disease is the accumulation of amyloid ? (A?) peptides generated by the proteolytic cleavage of the amyloid precursor protein (APP). APP overexpression leads to increased A? generation and Alzheimer’s disease in humans and altered neuronal migration and increased long term depression in mice. Conversely, reduction of APP expression results in decreased A? levels in mice as well as impaired learning and memory and decreased numbers of dendritic spines. Together these findings indicate that therapeutic interventions that aim to restore APP and A? levels must do so within an ideal range. To better understand the effects of modulating APP levels, we explored the mechanisms regulating APP expression focusing on post-transcriptional regulation. Such regulation can be mediated by RNA regulatory elements such as guanine quadruplexes (G-quadruplexes), non-canonical structured RNA motifs that affect RNA stability and translation. Via a bioinformatics approach, we identified a candidate G-quadruplex within the APP mRNA in its 3’UTR (untranslated region) at residues 3008–3027 (NM_201414.2). This sequence exhibited characteristics of a parallel G-quadruplex structure as revealed by circular dichroism spectrophotometry. Further, as with other G-quadruplexes, the formation of this structure was dependent on the presence of potassium ions. This G-quadruplex has no apparent role in regulating transcription or mRNA stability as wild type and mutant constructs exhibited equivalent mRNA levels as determined by real time PCR. Instead, we demonstrate that this G-quadruplex negatively regulates APP protein expression using dual luciferase reporter and Western blot analysis. Taken together, our studies reveal post-transcriptional regulation by a 3’UTR G-quadruplex as a novel mechanism regulating APP expression. PMID:26618502

  7. SorLA CR-Domains Protect the Amyloid Precursor Protein against Processing

    DEFF Research Database (Denmark)

    Mehmedbasic, Arnela; Christensen, Sofie K

    2014-01-01

    SorLA is a neuronal sorting receptor that is genetically associated with Alzheimer's disease. SorLA interacts directly with the amyloid precursor protein (APP) and affects the processing of the precursor, leading to a decreased generation of the amyloid-? (A?) peptide. The sorLA complement-type repeat (CR)-domains associate in vitro with APP, but the precise molecular determinants of sorLA-APP complex formation and the mechanisms responsible for the effect of binding on APP processing have not yet been elucidated. Here, we have generated protein expression constructs for sorLA devoid of the 11 CR-domains and for two sorLA mutants harboring substitutions of the fingerprint residues in the central CR-domains. We generated SH-SY5Y cell lines that stably express these sorLA variants to study the binding and processing of APP using co-immunoprecipitation and western blotting/ELISA assays, respectively. We found that the sorLA CR-cluster is essential for interaction with APP and that deletion of the CR-cluster abolishes the protection against APP processing. Mutation of identified fingerprint residues in the sorLA CR-domains leads to changes in the O-linked glycosylation of APP when expressed in SH-SY5Y cells. Our results provide novel information on the mechanisms behind the influence of sorLA activity on APP metabolism by controlling post-translational glycosylation in the Golgi, suggesting new strategies against amyloidogenesis in Alzheimer's disease.

  8. Amyloid precursor protein regulates migration and metalloproteinase gene expression in prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Toshiaki; Ikeda, Kazuhiro; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama 350-1241 (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama 350-1241 (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655 (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655 (Japan)

    2014-09-26

    Highlights: • APP knockdown reduced proliferation and migration of prostate cancer cells. • APP knockdown reduced expression of metalloproteinase and EMT-related genes. • APP overexpression promoted LNCaP cell migration. • APP overexpression increased expression of metalloproteinase and EMT-related genes. - Abstract: Amyloid precursor protein (APP) is a type I transmembrane protein, and one of its processed forms, ?-amyloid, is considered to play a central role in the development of Alzheimer’s disease. We previously showed that APP is a primary androgen-responsive gene in prostate cancer and that its increased expression is correlated with poor prognosis for patients with prostate cancer. APP has also been implicated in several human malignancies. Nevertheless, the mechanism underlying the pro-proliferative effects of APP on cancers is still not well-understood. In the present study, we explored a pathophysiological role for APP in prostate cancer cells using siRNA targeting APP (siAPP). The proliferation and migration of LNCaP and DU145 prostate cancer cells were significantly suppressed by siAPP. Differentially expressed genes in siAPP-treated cells compared to control siRNA-treated cells were identified by microarray analysis. Notably, several metalloproteinase genes, such as ADAM10 and ADAM17, and epithelial–mesenchymal transition (EMT)-related genes, such as VIM, and SNAI2, were downregulated in siAPP-treated cells as compared to control cells. The expression of these genes was upregulated in LNCaP cells stably expressing APP when compared with control cells. APP-overexpressing LNCaP cells exhibited enhanced migration in comparison to control cells. These results suggest that APP may contribute to the proliferation and migration of prostate cancer cells by modulating the expression of metalloproteinase and EMT-related genes.

  9. Amyloid precursor protein regulates migration and metalloproteinase gene expression in prostate cancer cells

    International Nuclear Information System (INIS)

    Highlights: • APP knockdown reduced proliferation and migration of prostate cancer cells. • APP knockdown reduced expression of metalloproteinase and EMT-related genes. • APP overexpression promoted LNCaP cell migration. • APP overexpression increased expression of metalloproteinase and EMT-related genes. - Abstract: Amyloid precursor protein (APP) is a type I transmembrane protein, and one of its processed forms, ?-amyloid, is considered to play a central role in the development of Alzheimer’s disease. We previously showed that APP is a primary androgen-responsive gene in prostate cancer and that its increased expression is correlated with poor prognosis for patients with prostate cancer. APP has also been implicated in several human malignancies. Nevertheless, the mechanism underlying the pro-proliferative effects of APP on cancers is still not well-understood. In the present study, we explored a pathophysiological role for APP in prostate cancer cells using siRNA targeting APP (siAPP). The proliferation and migration of LNCaP and DU145 prostate cancer cells were significantly suppressed by siAPP. Differentially expressed genes in siAPP-treated cells compared to control siRNA-treated cells were identified by microarray analysis. Notably, several metalloproteinase genes, such as ADAM10 and ADAM17, and epithelial–mesenchymal transition (EMT)-related genes, such as VIM, and SNAI2, were downregulated in siAPP-treated cells as compared to control cells. The expression of these genes was upregulated in LNCaP cells stably expressing APP when compared with control cells. APP-overexpressing LNCaP cells exhibited enhanced migration in comparison to control cells. These results suggest that APP may contribute to the proliferation and migration of prostate cancer cells by modulating the expression of metalloproteinase and EMT-related genes

  10. Sorting by the cytoplasmic domain of the amyloid precursor protein binding receptor SorLA.

    DEFF Research Database (Denmark)

    Nielsen, Morten S; Gustafsen, Camilla

    2007-01-01

    SorLA/LR11 (250 kDa) is the largest and most composite member of the Vps10p-domain receptors, a family of type 1 proteins preferentially expressed in neuronal tissue. SorLA binds several ligands, including neurotensin, platelet-derived growth factor-bb, and lipoprotein lipase, and via complex-formation with the amyloid precursor protein it downregulates generation of Alzheimer's disease-associated Abeta-peptide. The receptor is mainly located in vesicles, suggesting a function in protein sorting and transport. Here we examined SorLA's trafficking using full-length and chimeric receptors and find that its cytoplasmic tail mediates efficient Golgi body-endosome transport, as well as AP-2 complex-dependent endocytosis. Functional sorting sites were mapped to an acidic cluster-dileucine-like motif and to a GGA binding site in the C terminus. Experiments in permanently or transiently AP-1 mu1-chain-deficient cells established that the AP-1 adaptor complex is essential to SorLA's transport between Golgi membranes and endosomes. Our results further implicate the GGA proteins in SorLA trafficking and provide evidence that SNX1 and Vps35, as parts of the retromer complex or possibly in a separate context, are engaged in retraction of the receptor from endosomes. Udgivelsesdato: 2007-Oct

  11. Distinctive serum protein profiles involving abundant proteins in lung cancer patients based upon antibody microarray analysis

    Directory of Open Access Journals (Sweden)

    Rom William N

    2005-08-01

    Full Text Available Abstract Background Cancer serum protein profiling by mass spectrometry has uncovered mass profiles that are potentially diagnostic for several common types of cancer. However, direct mass spectrometric profiling has a limited dynamic range and difficulties in providing the identification of the distinctive proteins. We hypothesized that distinctive profiles may result from the differential expression of relatively abundant serum proteins associated with the host response. Methods Eighty-four antibodies, targeting a wide range of serum proteins, were spotted onto nitrocellulose-coated microscope slides. The abundances of the corresponding proteins were measured in 80 serum samples, from 24 newly diagnosed subjects with lung cancer, 24 healthy controls, and 32 subjects with chronic obstructive pulmonary disease (COPD. Two-color rolling-circle amplification was used to measure protein abundance. Results Seven of the 84 antibodies gave a significant difference (p Conclusion Our results suggest that a distinctive serum protein profile involving abundant proteins may be observed in lung cancer patients relative to healthy subjects or patients with chronic disease and may have utility as part of strategies for detecting lung cancer.

  12. Significant association between renal function and amyloid-positive area in renal biopsy specimens in AL amyloidosis

    Directory of Open Access Journals (Sweden)

    Kuroda Takeshi

    2012-09-01

    Full Text Available Abstract Background The kidney is a major target organ for systemic amyloidosis that often affects the kidney including proteinura, and elevated serum creatinine (Cr. The correlation between amount of amyloid deposits and clinical parameters is not known. The aim of this study was to clarify correlation the amyloid area in all renal biopsy specimen and clinical parameters. Methods Fifty-eight patients with an established diagnosis of AL amyloidosis participated in the study. All patients showed amyloid deposits in renal biopsies. We retrospectively investigated the correlation between clinical data and amyloid occupied area in whole renal biopsy specimens. Results The area occupied by amyloid was less than 10% in 57 of the 58 patients, and was under 2% in 40. For statistical analyses, %amyloid-positive areas were transformed to common logarithmic values (Log10%amyloid. Cr showed significant correlation with Log10%amyloid and estimated glomerular filtration rate (eGFR showed the significant negative correlation. Patient age, cleatinine clearance (Ccr, blood urea nitorogen, and urinary protein was not significantly correlated with Log10%amyloid. The correlation with other clinical factors such as sex, and serum concentrations of total protein, albumin, immunoglobulins, compliments was evaluated. None of these factors significantly correlated with Log10%amyloid. According to sex- and age- adjusted multiple linear regression analysis, Log10%amyloid had significant positive association with Cr and significant negative association with eGFR. Conclusion There is significant association between amyloid-positive area in renal tissue and renal function, especially Cr and eGFR. The level of Cr and eGFR may be a marker of amount of amyloid in renal tissue.

  13. Comparison between liver and serum concentrations of mannan binding protein.

    OpenAIRE

    Ryley, N. G.; Heryet, A R; Lu, J. (Jun); Reid, K. B.; Fleming, K. A.

    1993-01-01

    AIMS: To investigate staining patterns for mannan binding protein (MBP) by immunocytochemistry in liver biopsy specimens from patients with various hepatic disorders; to measure the serum MBP concentration in the patients at the time of biopsy; and to compare these to define further the role of MBP in disease. METHODS: Fifty seven consecutive patients with a variety of types of liver disease were studied. Fresh liver biopsy specimens were immunostained with anti-MBP and graded for intensity o...

  14. Diagnosis of alpha-1-antitrypsin deficiency by serum protein electrophoresis

    OpenAIRE

    Justin, V. G.; Venkatesh, T.

    2000-01-01

    Alpha-1-antitrypsin deficiency is a hereditary disease leading to hepatitis and cirrhosis. It is the most common genetic cause of liver disease in children which must inherit the tendency from both parents to develop. It acquires the highest priority in the differential diagnosis in a child with chronic liver disease. In this case report we substantiate the role of serum protein electrophoresis, in diagnosing alpha-1-antitrypsin deficiency.

  15. Serum Protein Electrophoresis in the Evaluation of Lytic Bone Lesions

    OpenAIRE

    Nystrom, Lukas M.; Buckwalter, Joseph A.; Syrbu, Sergei; Miller, Benjamin J.

    2013-01-01

    Serum protein electrophoresis (SPEP) is often obtained at the initial evaluation of a radiolucent bone lesion of unknown etiology. The results are considered convincing evidence of the presence or absence of a plasma cell neoplasm. The sensitivity and specificity of the SPEP have not been reported in this clinical scenario. Our purpose is to assess the diagnostic value of the SPEP in the initial work-up of the radiolucent bone lesion. We identified 182 patients undergoing evaluation of a radi...

  16. Acute serum amyloid A induces migration, angiogenesis, and inflammation in synovial cells in vitro and in a human rheumatoid arthritis/SCID mouse chimera model.

    LENUS (Irish Health Repository)

    Connolly, Mary

    2010-06-01

    Serum amyloid A (A-SAA), an acute-phase protein with cytokine-like properties, is expressed at sites of inflammation. This study investigated the effects of A-SAA on chemokine-regulated migration and angiogenesis using rheumatoid arthritis (RA) cells and whole-tissue explants in vitro, ex vivo, and in vivo. A-SAA levels were measured by real-time PCR and ELISA. IL-8 and MCP-1 expression was examined in RA synovial fibroblasts, human microvascular endothelial cells, and RA synovial explants by ELISA. Neutrophil transendothelial cell migration, cell adhesion, invasion, and migration were examined using transwell leukocyte\\/monocyte migration assays, invasion assays, and adhesion assays with or without anti-MCP-1\\/anti-IL-8. NF-kappaB was examined using a specific inhibitor and Western blotting. An RA synovial\\/SCID mouse chimera model was used to examine the effects of A-SAA on cell migration, proliferation, and angiogenesis in vivo. High expression of A-SAA was demonstrated in RA patients (p < 0.05). A-SAA induced chemokine expression in a time- and dose-dependent manner (p < 0.05). Blockade with anti-scavenger receptor class B member 1 and lipoxin A4 (A-SAA receptors) significantly reduced chemokine expression in RA synovial tissue explants (p < 0.05). A-SAA induced cell invasion, neutrophil-transendothelial cell migration, monocyte migration, and adhesion (all p < 0.05), effects that were blocked by anti-IL-8 or anti-MCP-1. A-SAA-induced chemokine expression was mediated through NF-kappaB in RA explants (p < 0.05). Finally, in the RA synovial\\/SCID mouse chimera model, we demonstrated for the first time in vivo that A-SAA directly induces monocyte migration from the murine circulation into RA synovial grafts, synovial cell proliferation, and angiogenesis (p < 0.05). A-SAA promotes cell migrational mechanisms and angiogenesis critical to RA pathogenesis.

  17. Identification and quantification of serum proteins secreted into the normal human jejunum

    DEFF Research Database (Denmark)

    Andersen, Vibeke; HegnhØj, J H

    1990-01-01

    The in vivo transfer of serum proteins to the human intestinal lumen was characterized by crossed immunoelectrophoretic analyses of intestinal perfusates from four healthy volunteers. Serum proteins with molecular masses below 100 kDa and the immunoglobulins were found in human jejunal perfusates. Larger serum proteins were either absent (alpha and beta lipoproteins) or present in small amounts (alpha 2-macroglobulin, haptoglobulin and ceruloplasmin). These results demonstrate the existence of a selective transfer of serum proteins to the intestinal lumen under physiological conditions. The intestinal clearance rate was 0.1 ml serum per hour per 10 cm jejunum for albumin, prealbumin, alpha 1-antitrypsin, orosomucoid, transferrin and haemopexin. The rate of secretion of total protein to the jejunal lumen was 100 mg protein per hour per 10 cm jejunum. About 45% was due to immunoglobulins and further 10-15% due to the remaining serum proteins. It is suggested that the serum proteins pass through the epithelium by a transcellular mechanism.

  18. Lead-Induced Accumulation of ?-Amyloid in the Choroid Plexus: Role of Low Density Lipoprotein Receptor Protein-1 and Protein Kinase C

    OpenAIRE

    Behl, Mamta; Zhang, Yanshu; Shi, Yunzhou; Cheng, JiXin; Du, Yansheng; Zheng, Wei

    2010-01-01

    The choroid plexus (CP), constituting the blood–cerebrospinal fluid barrier, has the capacity to remove beta-amyloid (A?) from the cerebrospinal fluid. Our previous work indicates that exposure to lead (Pb) results in A? accumulation in the CP by decreasing the expression of low density lipoprotein receptor protein-1 (LRP1), a protein involved in the transport and clearance of A?. The current study was designed to explore the relationship between A? accumulation, protein kinase C (PKC) activi...

  19. Interaction of thorium with blood serum proteins in vivo

    International Nuclear Information System (INIS)

    The distribution of thorium in the blood serum of rats was studied in vivo, using carrier-free 234Th and 59Fe-citrate solution. The chromatographic data presented in this short communication indicate that, as with plutonium, the iron-transport protein, transferrin, is the main carrier protein for thorium. Also, like plutonium, thorium could be displaced from the transferrin complex by excess iron. Further investigations are required to determine if plutonium and thorium are bound to the same sites on the transferrin molecule as iron and whether the binding mechanisms are similar. (U.K.)

  20. Protein Folding and Aggregation into Amyloid: The Interference by Natural Phenolic Compounds

    OpenAIRE

    Massimo Stefani; Stefania Rigacci

    2013-01-01

    Amyloid aggregation is a hallmark of several degenerative diseases affecting the brain or peripheral tissues, whose intermediates (oligomers, protofibrils) and final mature fibrils display different toxicity. Consequently, compounds counteracting amyloid aggregation have been investigated for their ability (i) to stabilize toxic amyloid precursors; (ii) to prevent the growth of toxic oligomers or speed that of fibrils; (iii) to inhibit fibril growth and deposition; (iv) to disassemble preform...

  1. Amyloids here, amyloids there…What’s wrong with them?

    OpenAIRE

    Gharibyan, Anna

    2012-01-01

    Amyloid formation is inherent property of proteins which under certain circumstances can become a pathologic feature of a group of diseases called amyloidosis. There are about 30 known human amyloidosis and more than 27 identified proteins involved in these pathologies.  Besides these proteins, there are a growing number of proteins non-related to diseases shown to form amyloid-like structures in vitro, which make them excellent tools for studying amyloid formation mechanisms, physicochemical...

  2. Design and synthesis of ?-site amyloid precursor protein cleaving enzyme (BACE1) inhibitors with in vivo brain reduction of ?-amyloid peptides.

    Science.gov (United States)

    Swahn, Britt-Marie; Kolmodin, Karin; Karlström, Sofia; von Berg, Stefan; Söderman, Peter; Holenz, Jörg; Berg, Stefan; Lindström, Johan; Sundström, Marie; Turek, Dominika; Kihlström, Jacob; Slivo, Can; Andersson, Lars; Pyring, David; Rotticci, Didier; Ohberg, Liselotte; Kers, Annika; Bogar, Krisztian; von Kieseritzky, Fredrik; Bergh, Margareta; Olsson, Lise-Lotte; Janson, Juliette; Eketjäll, Susanna; Georgievska, Biljana; Jeppsson, Fredrik; Fälting, Johanna

    2012-11-01

    The evaluation of a series of aminoisoindoles as ?-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitors and the discovery of a clinical candidate drug for Alzheimer's disease, (S)-32 (AZD3839), are described. The improvement in permeability properties by the introduction of fluorine adjacent to the amidine moiety, resulting in in vivo brain reduction of A?40, is discussed. Due to the basic nature of these compounds, they displayed affinity for the human ether-a-go-go related gene (hERG) ion channel. Different ways to reduce hERG inhibition and increase hERG margins for this series are described, culminating in (S)-16 and (R)-41 showing large in vitro margins with BACE1 cell IC(50) values of 8.6 and 0.16 nM, respectively, and hERG IC(50) values of 16 and 2.8 ?M, respectively. Several compounds were advanced into pharmacodynamic studies and demonstrated significant reduction of ?-amyloid peptides in mouse brain following oral dosing. PMID:22924815

  3. The Drosophila homologue of the amyloid precursor protein is a conserved modulator of Wnt PCP signaling.

    Science.gov (United States)

    Soldano, Alessia; Okray, Zeynep; Janovska, Pavlina; Tmejová, Kate?ina; Reynaud, Elodie; Claeys, Annelies; Yan, Jiekun; Atak, Zeynep Kalender; De Strooper, Bart; Dura, Jean-Maurice; Bryja, Vít?zslav; Hassan, Bassem A

    2013-01-01

    Wnt Planar Cell Polarity (PCP) signaling is a universal regulator of polarity in epithelial cells, but it regulates axon outgrowth in neurons, suggesting the existence of axonal modulators of Wnt-PCP activity. The Amyloid precursor proteins (APPs) are intensely investigated because of their link to Alzheimer's disease (AD). APP's in vivo function in the brain and the mechanisms underlying it remain unclear and controversial. Drosophila possesses a single APP homologue called APP Like, or APPL. APPL is expressed in all neurons throughout development, but has no established function in neuronal development. We therefore investigated the role of Drosophila APPL during brain development. We find that APPL is involved in the development of the Mushroom Body ?? neurons and, in particular, is required cell-autonomously for the ?-axons and non-cell autonomously for the ?-axons growth. Moreover, we find that APPL is a modulator of the Wnt-PCP pathway required for axonal outgrowth, but not cell polarity. Molecularly, both human APP and fly APPL form complexes with PCP receptors, thus suggesting that APPs are part of the membrane protein complex upstream of PCP signaling. Moreover, we show that APPL regulates PCP pathway activation by modulating the phosphorylation of the Wnt adaptor protein Dishevelled (Dsh) by Abelson kinase (Abl). Taken together our data suggest that APPL is the first example of a modulator of the Wnt-PCP pathway specifically required for axon outgrowth. PMID:23690751

  4. Chondroitin Sulfate Accelerates Trans-Golgi-to-Surface Transport of Proteoglycan Amyloid Precursor Protein.

    Science.gov (United States)

    Mihov, Deyan; Raja, Eva; Spiess, Martin

    2015-08-01

    The amyloid precursor protein (APP) is a membrane protein implicated in the pathogenesis of Alzheimer's disease. APP is a part-time proteoglycan, as splice variants lacking exon 15 are modified by a chondroitin sulfate glycosaminoglycan (GAG) chain. Investigating the effect of the GAG chain on the trafficking of APP in non-polarized cells, we found it to increase the steady-state surface-to-intracellular distribution, to reduce the rate of endocytosis and to accelerate transport kinetics from the trans-Golgi network (TGN) to the plasma membrane. Deletion of the cytosolic domain resulted in delayed surface arrival of GAG-free APP, but did not affect the rapid export kinetics of the proteoglycan form. Protein-free GAG chains showed the same TGN-to-cell surface transport kinetics as proteoglycan APP. Endosome ablation experiments were performed to distinguish between indirect endosomal and direct pathways to the cell surface. Surprisingly, TGN-to-cell surface transport of both GAG-free and proteoglycan APP was found to be indirect via transferrin-positive endosomes. Our results show that GAGs act as alternative sorting determinants in cellular APP transport that are dominant over cytoplasmic signals and involve distinct sorting mechanisms. PMID:25951880

  5. Metal ions and intrinsically disordered proteins and peptides: from Cu/Zn amyloid-? to general principles.

    Science.gov (United States)

    Faller, Peter; Hureau, Christelle; La Penna, Giovanni

    2014-08-19

    The interaction of d-block metal ions (Cu, Zn, Fe, etc.) with intrinsically disordered proteins (IDPs) has gained interest, partly due to their proposed roles in several diseases, mainly neurodegenerative. A prominent member of IDPs is the peptide amyloid-? (A?) that aggregates into metal-enriched amyloid plaques, a hallmark of Alzheimer's disease, in which Cu and Zn are bound to A?. IDPs are a class of proteins and peptides that lack a unique 3D structure when the protein is isolated. This disordered structure impacts their interaction with metal ions compared with structured metalloproteins. Metalloproteins either have a preorganized metal binding site or fold upon metal binding, resulting in defined 3D structure with a well-defined metal site. In contrast, for A? and likely most of the other IDPs, the affinity for Cu(I/II) and Zn(II) is weaker and the interaction is flexible with different coordination sites present. Coordination of Cu(I/II) with A? is very dynamic including fast Cu-exchange reactions (milliseconds or less) that are intrapeptidic between different sites as well as interpeptidic. This highly dynamic metal-IDP interaction has a strong impact on reactivity and potential biological role: (i) Due to the low affinity compared with classical metalloproteins, IDPs likely bind metals only at special places or under special conditions. For A?, this is likely in the neurons that expel Zn or Cu into the synapse and upon metal dysregulation occurring in Alzheimer's disease. (ii) Amino acid substitutions (mutations) on noncoordinating residues can change drastically the coordination sphere. (iii) Considering the Cu/Zn-A? aberrant interaction, therapeutic strategies can be based on removal of Cu/Zn or precluding their binding to the peptide. The latter is very difficult due to the multitude of metal-binding sites, but the fast koff facilitates removal. (iv) The high flexibility of the Cu-A? complex results in different conformations with different redox activity. Only some conformations are able to produce reactive oxygen species. (v) Other, more specific catalysis (like enzymes) is very unlikely for Cu/Zn-A?. (vi) The Cu/Zn exchange reactions with A? are faster than the aggregation process and can hence have a strong impact on this process. In conclusion, the coordination chemistry is fundamentally different for most of IDPs compared with the classical, structured metalloproteins or with (bio)-inorganic complexes. The dynamics is a key parameter to understand this interaction and its potential biological impact. PMID:24871565

  6. HAPTOGLOBIN AND SERUM AMYLOID A IN SUBACUTE RUMINAL ACIDOSIS IN GOATS / HAPTOGLOBINA Y PROTEÍNA AMILÓIDE SÉRICA A EN ACIDOSIS RUMINAL SUBAGUADA EN CABRAS

    Scientific Electronic Library Online (English)

    F.H.D, González; F.H, Ruipérez; J.M, Sánchez; J.C, Souza; S, Martínez-Subiela; J.J, Cerón.

    2010-12-01

    Full Text Available La acidosis ruminal es un trastorno frecuente en cabras como consecuencia de errores en el manejo alimentario en animales no adaptados a dietas que contienen carbohidratos fácilmente fermentables. La forma subaguda de la enfermedad es de difícil diagnóstico toda vez que no muestra evidencia de signo [...] s clínicos claros y los parámetros ácido-básicos pueden permanecer en el rango normal. El presente estudio tuvo por objetivo probar la hipótesis de que la haptoglobina y la proteína amilóide sérica A, las dos proteínas de fase aguda más importantes en rumiantes, pueden ser útiles como marcadores de acidosis subaguda en cabras. Se indujo acidosis ruminal a seis cabras de la raza Murciano-Granadina, no adaptadas al consumo de concentrado, mediante el suministro de una dieta con 60% de concentrado y 40% de heno de alfalfa durante 5 días. Dos cabras fueron sometidas a fistulación ruminal para comprobar el efecto del tratamiento sobre el pH del rumen. A todos los animales se les tomaron muestras de sangre y orina el día anterior a la inducción, durante el período de inducción y hasta 18 días después de la inducción (período de recuperación). El pH ruminal cayó a menos de 5,5 durante el período de inducción de acidosis en las cabras fistuladas, mientras que la mitad de las cabras tuvieron diarrea al tercer día de la inducción de acidosis. Los parámetros gasométricos indicaron que los mecanismos compensatorios fueron eficientes para mantener el equilibrio ácido-básico. La haptoglobina sérica presentó un aumento moderado durante el período de inducción de acidosis, mientras que la amilóide sérica A no presentó cambios. Los resultados sugieren que la haptoglobina puede utilizarse como un potencial indicador de acidosis ruminal en cabras. Abstract in english Ruminal acidosis is a frequent disorder that occurs in goats as a consequence of feeding mistakes in animals not adapted to a diet of easily fermentable carbohydrates. The subacute form of the disease is difficult to diagnose because no apparent signs are shown and the acid-base parameters may remai [...] n within the normal range. The present study aimed at testing the hypothesis that haptoglobin (Hp) and serum amyloid A (SAA), the two major acute phase proteins in ruminants, may be useful as markers of subacute acidosis in goats. A subacute acidosis was induced in six Murciano-Granadina goats through a diet of 60% mixed feed-40% alfalfa hay offered during 5 days to goats not adapted to eat mixed feed. Two goats were rumen-fistulated to investigate the effect of feeding on ruminal pH. Sampling of blood and urine of all animals was done before the induction of the acidosis, during 5 days after the onset of induction and for 18 days after the induction (recovery period). Ruminal pH in the fistulated goats dropped to less than 5.5 during the induction period, and half of the goats had diarrhea on the third day after the induction of acidosis. Acid-base parameters showed that the acid-base compensatory mechanisms were efficient in maintaining the equilibrium. Serum Hp had a moderate increase during the induction period, while SAA did not change. These results suggest that Hp might be a potential marker for ruminal acidosis in goats.

  7. Injury severity and serum amyloid A correlate with plasma oxidation-reduction potential in multi-trauma patients: a retrospective analysis

    Directory of Open Access Journals (Sweden)

    Mains Charles W

    2009-11-01

    Full Text Available Abstract Background In critical injury, the occurrence of increased oxidative stress or a reduced antioxidant status has been observed. The purpose of this study was to correlate the degree of oxidative stress, by measuring the oxidation-reduction potential (ORP of plasma in the critically injured, with injury severity and serum amyloid A (SAA levels. Methods A total of 140 subjects were included in this retrospective study comprising 3 groups: healthy volunteers (N = 21, mild to moderate trauma (ISS Results ORP maxima were reached on day 3 (± 0.4 SEM and day 5 (± 0.5 SEM for the ISS Conclusion The results suggest the presence of an oxidative environment in the plasma of the critically injured as measured by ORP. More importantly, ORP can differentiate the degree of oxidative stress based on the severity of the trauma and degree of inflammation.

  8. The Role of 6-Gingerol on Inhibiting Amyloid ? Protein-Induced Apoptosis in PC12 Cells.

    Science.gov (United States)

    Zeng, Gao-Feng; Zong, Shao-Hui; Zhang, Zhi-Yong; Fu, Song-Wen; Li, Ke-Ke; Fang, Ye; Lu, Li; Xiao, De-Qiang

    2015-10-01

    Our previous study suggests that ginger root extract can reverse behavioral dysfunction and prevent Alzheimer's disease (AD)-like symptoms induced by the amyloid-? protein (A?) in a rat model. 6-Gingerol is the major gingerol in ginger rhizomes, but its effect on the treatment of AD remains unclear. In this study, we aimed to determine if 6-gingerol had a protective effect on A?1-42-induced damage and apoptotic death in rat pheochromocytoma cells (PC12 cells) and to investigate the underlying mechanisms by which 6-gingerol may exert its neuroprotective effects. Our results indicated that pre-treatment with 6-gingerol significantly increased cell viability and reduced cell apoptosis in A?1-42-treated cells. Moreover, 6-gingerol pretreatment markedly reduced the level of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), the production of nitric oxide (NO), and the leakage of lactate dehydrogenase (LDH) and increased superoxide dismutase (SOD) activity compared with the A?1-42 treatment group. In addition, 6-gingerol pretreatment also significantly enhanced the protein levels of phosphorylated Akt (p-Akt) and glycogen synthase kinase-3? (p-GSK-3?). Overall, these results indicate that 6-gingerol exhibited protective effects on apoptosis induced by A?1-42 in cultured PC12 cells by reducing oxidative stress and inflammatory responses, suppressing the activation of GSK-3? and enhancing the activation of Akt, thereby exerting neuroprotective effects. Therefore, 6-gingerol may be useful in the prevention and/or treatment of AD. PMID:25811848

  9. Altered Innate Immune and Glial Cell Responses to Inflammatory Stimuli in Amyloid Precursor Protein Knockout Mice

    Science.gov (United States)

    Carrano, Anna; Das, Pritam

    2015-01-01

    Amyloid precursor protein (APP) and its cleaved products have been reported to have important functions in CNS health, including in memory and synapse formation, cell survival and neuroprotection. Furthermore APP and its cleaved products have been shown to be transiently increased in response to various CNS stressors, suggesting a role in response to acute cellular injury. In an attempt to further understand the function of APP in response to CNS injury, we have used intracranial LPS injection as an inflammatory injury model in APP knock out mice (APPKO). Our data show that innate immune responses to LPS injection is significantly blunted in APPKO mice compared to APP sufficient wild type (BL6) mice. Morphologically, glial cells in APPKO mice appear less reactive, with shorter ramified processes and smaller cell bodies in response to LPS. Additionally, quantitative RT-PCR analysis for several glia markers and innate immune cytokine levels (e.g. TNF?, IL-6, IL-1? and IL-10) showed significantly reduced expression levels in LPS injected APPKO mice. In vitro cell culture assays confirmed this attenuated response to LPS stimulation by primary microglial cells isolated from APPKO mice. Our data suggests that APP full length protein and/or its cleaved products are necessary to mount a complete and effective innate immune cell response to inflammatory injury. PMID:26447481

  10. Metalloprotease meprin beta generates nontoxic N-terminal amyloid precursor protein fragments in vivo.

    Science.gov (United States)

    Jefferson, Tamara; ?auševi?, Mirsada; auf dem Keller, Ulrich; Schilling, Oliver; Isbert, Simone; Geyer, Rebecca; Maier, Wladislaw; Tschickardt, Sabrina; Jumpertz, Thorsten; Weggen, Sascha; Bond, Judith S; Overall, Christopher M; Pietrzik, Claus U; Becker-Pauly, Christoph

    2011-08-01

    Identification of physiologically relevant substrates is still the most challenging part in protease research for understanding the biological activity of these enzymes. The zinc-dependent metalloprotease meprin ? is known to be expressed in many tissues with functions in health and disease. Here, we demonstrate unique interactions between meprin ? and the amyloid precursor protein (APP). Although APP is intensively studied as a ubiquitously expressed cell surface protein, which is involved in Alzheimer disease, its precise physiological role and relevance remain elusive. Based on a novel proteomics technique termed terminal amine isotopic labeling of substrates (TAILS), APP was identified as a substrate for meprin ?. Processing of APP by meprin ? was subsequently validated using in vitro and in vivo approaches. N-terminal APP fragments of about 11 and 20 kDa were found in human and mouse brain lysates but not in meprin ?(-/-) mouse brain lysates. Although these APP fragments were in the range of those responsible for caspase-induced neurodegeneration, we did not detect cytotoxicity to primary neurons treated by these fragments. Our data demonstrate that meprin ? is a physiologically relevant enzyme in APP processing. PMID:21646356

  11. Metalloprotease Meprin ? Generates Nontoxic N-terminal Amyloid Precursor Protein Fragments in Vivo*

    Science.gov (United States)

    Jefferson, Tamara; ?auševi?, Mirsada; auf dem Keller, Ulrich; Schilling, Oliver; Isbert, Simone; Geyer, Rebecca; Maier, Wladislaw; Tschickardt, Sabrina; Jumpertz, Thorsten; Weggen, Sascha; Bond, Judith S.; Overall, Christopher M.; Pietrzik, Claus U.; Becker-Pauly, Christoph

    2011-01-01

    Identification of physiologically relevant substrates is still the most challenging part in protease research for understanding the biological activity of these enzymes. The zinc-dependent metalloprotease meprin ? is known to be expressed in many tissues with functions in health and disease. Here, we demonstrate unique interactions between meprin ? and the amyloid precursor protein (APP). Although APP is intensively studied as a ubiquitously expressed cell surface protein, which is involved in Alzheimer disease, its precise physiological role and relevance remain elusive. Based on a novel proteomics technique termed terminal amine isotopic labeling of substrates (TAILS), APP was identified as a substrate for meprin ?. Processing of APP by meprin ? was subsequently validated using in vitro and in vivo approaches. N-terminal APP fragments of about 11 and 20 kDa were found in human and mouse brain lysates but not in meprin ??/? mouse brain lysates. Although these APP fragments were in the range of those responsible for caspase-induced neurodegeneration, we did not detect cytotoxicity to primary neurons treated by these fragments. Our data demonstrate that meprin ? is a physiologically relevant enzyme in APP processing. PMID:21646356

  12. Relaxation dynamics of piroxicam structures within human serum albumin protein.

    Science.gov (United States)

    El-Kemary, Maged; Gil, Micha?; Douhal, Abderrazzak

    2007-06-14

    We report on steady-state and ps-time-resolved emission studies of piroxicam (1) drug within human serum albumin (HSA) protein in cyclodextrin and in neat solvents. The steady-state results indicate that 1 binds to HSA protein and that two binding sites are involved. The fluorescence decays corresponding to site I in subdomain IIA and to site II in subdomain IIIA have time constants of approximately 60 ps and approximately 360 ps, respectively. The results suggest that the anion forms bind to site I, whereas the zwitterionic ones bind to site II. The energy-transfer process from excited tryptophan to 1 can occur with moderate efficiency (50%). The rotational time of 1 encapsulated by HSA indicates diffusion within the protein. These findings can be used for a better understanding of piroxicam and HSA interactions. PMID:17506539

  13. Memory-enhancing effects of secreted forms of the ?-amyloid precursor protein in normal and amnestic mice

    OpenAIRE

    Meziane, H.; Dodart, J.-C.; Mathis, C; Little, S.; Clemens, J.; Paul, S M; Ungerer, A.

    1998-01-01

    When administered intracerebroventricularly to mice performing various learning tasks involving either short-term or long-term memory, secreted forms of the ?-amyloid precursor protein (APPs751 and APPs695) have potent memory-enhancing effects and block learning deficits induced by scopolamine. The memory-enhancing effects of APPs were observed over a wide range of extremely low doses (0.05-5,000 pg intracerebroventricularly), blocked by anti-APPs antisera, and observed when APPs was administ...

  14. Chronic pre-treatment with memantine prevents amyloid-beta protein-mediated long-term potentiation disruption?

    OpenAIRE

    Li, Fushun; Chen, Xiaowei (Sylvia); WANG, FEIMING; Xu, Shujun; Chang, Lan; ANWYL, ROGER; WANG, QINWEN

    2013-01-01

    Previous studies indicate that memantine, a low-affinity N-methyl-D-aspartate receptor antagonist, exerted acute protective effects against amyloid-? protein-induced neurotoxicity. In the present study, the chronic effects and mechanisms of memantine were investigated further using electrophysiological methods. The results showed that 7-day intraperitoneal application of memantine, at doses of 5 mg/kg or 20 mg/kg, did not alter hippocampal long-term potentiation induction in rats, while 40 mg...

  15. Serum protein concentrations, including acute phase proteins, in calves experimentally infected with Salmonella Dublin

    Directory of Open Access Journals (Sweden)

    Daniela Gomes da Silva

    2011-07-01

    Full Text Available The aim of this study was to evaluate serum protein concentrations in calves experimentally inoculated with Salmonella Dublin. Twelve healthy 10 to 15-day-old Holstein calves were randomly allotted into two groups, control and infected with 10(8 CFU of Salmonella Dublin orally. The calves were subjected to physical evaluation and blood samples were collected shortly before administration of the bacteria and also 24, 48, 72, 96, 120 and 168 hours post-infection. The concentration of serum proteins was determined through sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE. Thirty serum proteins ranging from molecular weight of 24,000 Da to molecular weight of 236,000 Da were detected. Serum concentrations of ceruloplasmin (125,000 Da, haptoglobin (45,000 Da, acid glycoprotein (40,000 Da and a 34,000 Da protein were significantly increased in the experimentally infected calves, when compared with their concentrations in the control animals. Therefore, this study showed that S. Dublin infection could lead to the increase of certain serum proteins in calves.

  16. Environmental conditions influence hippocampus-dependent behaviours and brain levels of amyloid precursor protein in rats.

    Science.gov (United States)

    Teather, Lisa A; Magnusson, Jane E; Chow, Christina M; Wurtman, Richard J

    2002-12-01

    Sprague-Dawley rats were reared in enriched (EC; group housing, exposure to stimulating objects, frequent handling) or restricted (RC; individual housing, no exposure to stimulating objects, minimal handling) environments starting on day 23 of life. At six months of age, they underwent behavioural tests to assess 'cognitive' and 'stimulus-response' memory, selective attention, and inflammatory pain processing. Alterations in synapses and cell survival may occur as a result of environment differences; therefore we assessed the brain levels of several proteins implicated in neurite outgrowth, synaptogenesis, and cell survival. Brains were dissected and analysed for amyloid precursor protein (APP) and other synaptic and cytoskeletal proteins using Western blotting. The performance of EC animals in a hidden platform water maze task, and in a test of selective attention (both of which are thought to involve the hippocampus) was superior to that of RC animals. In contrast, performance of RC animals on two stimulus-response tasks, the visible platform water maze test and simple visual discrimination (both of which are thought to be hippocampal independent) was indistinguishable from that of EC animals. Male EC rats displayed a different behavioural response to formalin during the inflammatory phase of nociception--the phase affected by hippocampal processing; a similar trend was observed in females. Female but not male RC rats exhibited elevated plasma corticosterone levels; adrenal weights were unaffected by environmental conditions. Region-specific increases in brain levels of APP, neurofilament-70 (NF-70), and platelet-activating factor receptor (PAF-R) were found in EC rats. These data suggest that enriched animals manifest enhanced functioning of certain hippocampus-mediated behaviours when compared with that of their restricted counterparts; and that brain levels of various synaptic and structural proteins involved in neurite outgrowth, cell survival, and synaptogenesis, are affected by environmental factors. PMID:12492435

  17. Chronic pre-treatment with memantine prevents amyloid-beta protein-mediated long-term potentiation disruption?

    Science.gov (United States)

    Li, Fushun; Chen, Xiaowei; Wang, Feiming; Xu, Shujun; Chang, Lan; Anwyl, Roger; Wang, Qinwen

    2013-01-01

    Previous studies indicate that memantine, a low-affinity N-methyl-D-aspartate receptor antagonist, exerted acute protective effects against amyloid-? protein-induced neurotoxicity. In the present study, the chronic effects and mechanisms of memantine were investigated further using electrophysiological methods. The results showed that 7-day intraperitoneal application of memantine, at doses of 5 mg/kg or 20 mg/kg, did not alter hippocampal long-term potentiation induction in rats, while 40 mg/kg memantine presented potent long-term potentiation inhibition. Then further in vitro studys were carried out in 5 mg/kg and 20 mg/kg memantine treated rats. We found that 20 mg/kg memantine attenuated the potent long-term potentiation inhibition caused by exposure to amyloid-? protein in the dentate gyrus in vitro. These findings are the first to demonstrate the antagonizing effect of long-term systematic treatment of memantine against amyloid-? protein triggered long-term potentiation inhibition to improve synaptic plasticity. PMID:25206371

  18. Structures of segments of [alpha]-synuclein fused to maltose-binding protein suggest intermediate states during amyloid formation

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Minglei; Cascio, Duilio; Sawaya, Michael R.; Eisenberg, David (UCLA)

    2011-08-29

    Aggregates of the protein {alpha}-synuclein are the main component of Lewy bodies, the hallmark of Parkinson's disease. {alpha}-Synuclein aggregates are also found in many human neurodegenerative diseases known as synucleinopathies. In vivo, {alpha}-synuclein associates with membranes and adopts {alpha}-helical conformations. The details of how {alpha}-synuclein converts from the functional native state to amyloid aggregates remain unknown. In this study, we use maltose-binding protein (MBP) as a carrier to crystallize segments of {alpha}-synuclein. From crystal structures of fusions between MBP and four segments of {alpha}-synuclein, we have been able to trace a virtual model of the first 72 residues of {alpha}-synuclein. Instead of a mostly {alpha}-helical conformation observed in the lipid environment, our crystal structures show {alpha}-helices only at residues 1-13 and 20-34. The remaining segments are extended loops or coils. All of the predicted fiber-forming segments based on the 3D profile method are in extended conformations. We further show that the MBP fusion proteins with fiber-forming segments from {alpha}-synuclein can also form fiber-like nano-crystals or amyloid-like fibrils. Our structures suggest intermediate states during amyloid formation of {alpha}-synuclein.

  19. Molecular Structures of Amyloid and Prion Fibrils: Consensus vs. Controversy

    OpenAIRE

    Tycko, Robert; Wickner, Reed B.

    2013-01-01

    Many peptides and proteins self-assemble into amyloid fibrils, including polypeptides that are associated with human amyloid diseases, mammalian and fungal prion proteins, and proteins that are believed to have biologically functional amyloid states. Proper understanding of the common propensity for polypeptides to form amyloid fibrils depends on elucidation of the molecular structures of these fibrils, as does rational design of amyloid inhibitors and imaging agents. Whereas amyloid fibril s...

  20. Embryo culture in teratological surveillance and serum proteins in development. Progress report, 1979-1980

    Energy Technology Data Exchange (ETDEWEB)

    Klein, N.W.

    1980-07-01

    Research progress for the period 1979-1980 is reported. The feasibility of using rat embryo cultures to test the teratogenic activity of serum was studied. The mechanisms regulating the synthesis of serum proteins were investigated. (ACR)

  1. Age does not influence the serum protein binding of bupivacaine.

    OpenAIRE

    Veering, B T; Burm, A G; Gladines, M P; Spierdijk, J

    1991-01-01

    The serum protein binding of bupivacaine was studied in 74 subjects, 39 males and 35 females, aged 20-90 years, without evidence of acute or chronic inflammatory disease or malignancy. Subjects were drug free for at least 1 month. The free fractions of bupivacaine did not change with age in either males or females. This is in keeping with the lack of effect of age on AAG concentrations. Free fractions of bupivacaine were slightly higher in females as compared with males. The previously observ...

  2. Acute phase proteins as diagnostic markers in horses with colic

    DEFF Research Database (Denmark)

    Pihl, Tina Holberg; Scheepers, Elrien; Sanz, Macarena; Goddard, Amelia; Page, Patrick; Toft, Nils; Kjeldgaard-Hansen, Mads; Andersen, Pia Haubro; Jacobsen, Stine

    2013-01-01

    Take Home Message: Serum amyloid A (SAA) in serum was the biomarker which best improved the clinical assessment in differentiating infectious colic from surgical colic. Introduction: The objective of this study was to investigate the ability of the acute phase proteins (APPs); Serum amyloid A, haptoglobin and fibrinogen to differentiate between horses with infectious non-surgical colic and surgical colic. Materials & Methods: The performance of the APPs was evaluated individually and in combinat...

  3. Curli functional amyloid systems are phylogenetically widespread and display large diversity in operon and protein structure

    DEFF Research Database (Denmark)

    Dueholm, Morten S; Albertsen, Mads

    2012-01-01

    Escherichia coli and a few other members of the Enterobacteriales can produce functional amyloids known as curli. These extracellular fibrils are involved in biofilm formation and studies have shown that they may act as virulence factors during infections. It is not known whether curli fibrils are restricted to the Enterobacteriales or if they are phylogenetically widespread. The growing number of genome-sequenced bacteria spanning many phylogenetic groups allows a reliable bioinformatic investigation of the phylogenetic diversity of the curli system. Here we show that the curli system is phylogenetically much more widespread than initially assumed, spanning at least four phyla. Curli fibrils may consequently be encountered frequently in environmental as well as pathogenic biofilms, which was supported by identification of curli genes in public metagenomes from a diverse range of habitats. Identification and comparison of curli subunit (CsgA/B) homologs show that these proteins allow a high degree of freedom in their primary protein structure, although a modular structure of tightly spaced repeat regions containing conserved glutamine, asparagine and glycine residues has to be preserved. In addition, a high degree of variability within the operon structure of curli subunits between bacterial taxa suggests that the curli fibrils might have evolved to fulfill specific functions. Variations in the genetic organization of curli genes are also seen among different bacterial genera. This suggests that some genera may utilize alternative regulatory pathways for curli expression. Comparison of phylogenetic trees of Csg proteins and the 16S rRNA genes of the corresponding bacteria showed remarkably similar overall topography, suggesting that horizontal gene transfer is a minor player in the spreading of the curli system.

  4. Competitive protein adsorption to polymer surface from human serum

    DEFF Research Database (Denmark)

    Holmberg, Maria; Jensen, Karin Bagger Stibius

    2008-01-01

    Surface modification by "soft" plasma polymerisation to obtain a hydrophilic and non-fouling polymer surface has been validated using radioactive labelling. Adsorption to unmodified and modified polymer surfaces, from both single protein and human serum solutions, has been investigated. By using different radioisotopes, albumin and Immunoglobulin G (IgG) adsorption has been monitored simultaneously during competitive adsorption processes, which to our knowledge has not been reported in the literature before. Results show that albumin and IgG adsorption is dependent on adsorption time and on the presence and concentration of other proteins in bulk solutions during adsorption. Generally, lower albumin and IgG adsorption was observed on the modified and more hydrophilic polymer surfaces, but otherwise the modified and unmodified polymer surfaces showed the same adsorption characteristics.

  5. Serum protein biomarkers relevant to hepatocellular carcinoma and their detection.

    Science.gov (United States)

    Waidely, Eric; Al-Yuobi, Abdul-Rahman Obaid; Bashammakh, A S; El-Shahawi, Mohammad S; Leblanc, Roger M

    2016-01-01

    Hepatocellular carcinoma (HCC) is one of the most recurrent and lethal cancers worldwide. The low survival rate of this particular strain of carcinoma is largely due to the late stages at which it is diagnosed. Tumorigenesis of hepatocellular carcinoma is most frequently detected through ultrasonography, magnetic resonance imaging and computerized tomography scans, however, these methods are poor for detection of early tumor development. This review presents alternative hepatocellular carcinoma detection techniques through the use of protein and enzyme/isozyme biomarkers. The detection methods used to determine the serum levels of ?-fetoprotein (AFP), glypican-3 (GPC3), Golgi protein 73 (GP73), ?-l-fucosidase (AFU), des-?-carboxyprothrombin (DCP), ?-glutamyl transferase (GGT) and squamous cell carcinoma antigen (SCCA) are presented and each marker's respective validity in the diagnosis of hepatocellular carcinoma is evaluated. PMID:26606739

  6. Pulsed laser deposition of bovine serum albumin protein thin films

    International Nuclear Information System (INIS)

    Thin films of the bovine serum albumin protein (BSA) were prepared by pulsed laser deposition (PLD). Using a KrF excimer laser beam focused on a target made of pressed powder with a fluence in the 1-2 J cm-2 range, films of about 1 ?m thickness and low roughness could be obtained on silica substrates at room temperature and under a pressure of about 10-5 mbar. The Fourier transform infrared (FTIR) spectra of the films, recorded in attenuated total reflection (ATR) configuration, are nearly identical to those of the starting powders. For fluences lower than 0.6 J cm-2, however, the structure of the molecule is not preserved. Atomic force microscopy (AFM) images show the protein to be deposited as particles of about 100 nm diameter without clear ordering and the films to have low roughness. Refractive index and thickness of the films were measured by m-lines spectroscopy

  7. Involvement of amyloid precursor protein in memory formation in the rat: an indirect antibody approach.

    Science.gov (United States)

    Huber, G; Martin, J R; Löffler, J; Moreau, J L

    1993-02-19

    The potential role of different isoforms of amyloid precursor proteins (APPs) in memory and learning processes was investigated in rats using antibodies differentiating between APP isoforms containing or lacking the Kunitz protease inhibitor (KPI) domain. Rats received intracerebroventricular injection of control immunoglobulins (IgGs), anti-KPI-APP (= anti-P3) or anti-N-terminus-APP (= anti-P4). No immediate effects on learning of a passive avoidance task were observed; however, performance evaluated 1 day later was somewhat impaired by the anti-P3 antibody (reacting with APPKPI) and even more markedly impaired by the anti-P4 antibody (reacting with both APP695 and APPKPI) relative to control antibody. The antibodies did not affect performance of an active avoidance task acquired prior to the experimental treatment or active avoidance learning 8 days post-treatment. These results suggest that blockade of APP by an antibody injected intracerebroventricularly impairs the consolidation and/or retrieval of memory in rats. PMID:8461988

  8. Cleavage of amyloid precursor protein by an archaeal presenilin homologue PSH

    Science.gov (United States)

    Dang, Shangyu; Wu, Shenjie; Wang, Jiawei; Li, Hongbo; Huang, Min; He, Wei; Li, Yue-Ming; Wong, Catherine C. L.; Shi, Yigong

    2015-01-01

    Aberrant cleavage of amyloid precursor protein (APP) by ?-secretase contributes to the development of Alzheimer’s disease. More than 200 disease-derived mutations have been identified in presenilin (the catalytic subunit of ?-secretase), making modulation of ?-secretase activity a potentially attractive therapeutic opportunity. Unfortunately, the technical challenges in dealing with intact ?-secretase have hindered discovery of modulators and demand a convenient substitute approach. Here we report that, similar to ?-secretase, the archaeal presenilin homolog PSH faithfully processes the substrate APP C99 into A?42, A?40, and A?38. The molar ratio of the cleavage products A?42 over A?40 by PSH is nearly identical to that by ?-secretase. The proteolytic activity of PSH is specifically suppressed by presenilin-specific inhibitors. Known modulators of ?-secretase also modulate PSH similarly in terms of the A?42/A?40 ratio. Structural analysis reveals association of a known ?-secretase inhibitor with PSH between its two catalytic aspartate residues. These findings identify PSH as a surrogate protease for the screening of agents that may regulate the protease activity and the cleavage preference of ?-secretase. PMID:25733893

  9. Nicotine-induced plasticity in the retinocollicular pathway: Evidence for involvement of amyloid precursor protein.

    Science.gov (United States)

    Gonçalves, R G J; Vasques, J F; Trindade, P; Serfaty, C A; Campello-Costa, P; Faria-Melibeu, A C

    2016-01-28

    During early postnatal development retinocollicular projections undergo activity-dependent synaptic refinement that results in the formation of precise topographical maps in the visual layers of the superior colliculus (SC). Amyloid Precursor Protein (APP) is a widely expressed transmembrane glycoprotein involved in the regulation of several aspects of neural development, such as neurite outgrowth, synapse formation and plasticity. Stimulation of cholinergic system has been found to alter the expression and processing of APP in different cell lines. Herein, we investigated the effect of nicotine on the development of retinocollicular pathway and on APP metabolism in the SC of pigmented rats. Animals were submitted to intracranial Elvax implants loaded with nicotine or phosphate-buffered saline (vehicle) at postnatal day (PND) 7. The ipsilateral retinocollicular pathway of control and experimental groups was anterogradely labeled either 1 or 3weeks after surgery (PND 14 or PND 28). Local nicotine exposure produces a transitory sprouting of uncrossed retinal axons outside their main terminal zones. Nicotine also increases APP content and its soluble neurotrophic fragment sAPP?. Furthermore, nicotine treatment upregulates nicotinic acetylcholine receptor ?7 and ?2 subunits. Taken together, these data indicate that nicotine disrupts the ordering and topographic mapping of axons in the retinocollicular pathway and facilitates APP processing through the nonamyloidogenic pathway, suggesting that sAPP? may act as a trophic agent that mediates nicotine-induced morphological plasticity. PMID:26601777

  10. The effect of zinc on amyloid ?-protein assembly and toxicity: A mechanistic investigation

    Science.gov (United States)

    Solomonov, Inna; Sagi, Irit

    2014-10-01

    Neurotoxic assemblies of amyloid ?-protein (A?) are widely believed to be the cause for Alzheimer's disease (AD). Therefore, understanding the factors and mechanisms that control, modulate, and inhibit formation of these assemblies is crucial for the development of therapeutic intervention of AD. This information also can contribute significantly to our understanding of the mechanisms of other amyloidosis diseases, such as Parkinson's disease, Huntington's disease, type 2 diabetes, amyotrophic lateral sclerosis (Lou Gehrig's disease) and prion diseases (e.g. Mad Cow disease). We have developed a multidisciplinary experimental strategy to study structural and dynamic mechanistic aspects that underlie the A? assembly process. Utilizing this strategy, we explored the molecular basis leading to the perturbation of the A? assembly process by divalent metal ions, mainly Zn2+ ions. Using Zn2+ as reaction physiological relevant probes, it was demonstrated that Zn2+ rapidly (milliseconds) induce self-assembly of A? aggregates and stabilize them in a manner that prevents formation of A? fibrils. Importantly, the early-formed intermediates are substantially more neurotoxic than fibrils. Our results suggest that relevant A? modulators should be targeted against the rapidly evolved intermediate states of A? assembly. The design of such modulators is challenging, as they have to compete with different natural mediators (such as Zn2+) of A? aggregation, which diverse A? assemblies in both specific and nonspecific manners.

  11. Overexpression of amyloid precursor protein increases copper content in HEK293 cells

    Energy Technology Data Exchange (ETDEWEB)

    Suazo, Miriam; Hodar, Christian; Morgan, Carlos [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Cerpa, Waldo [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Cambiazo, Veronica [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Millenium Nucleus CGC, Universidad de Chile (Chile); Inestrosa, Nibaldo C. [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Gonzalez, Mauricio, E-mail: mgonzale@inta.cl [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile)

    2009-05-15

    Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu{sup 2+} binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu{sup 2+} reduction and {sup 64}Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu{sup 2+} reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu{sup 2+} ions. Moreover, wild-type cells exposed to both Cu{sup 2+} ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu{sup 2+} reductase activity and increased {sup 64}Cu uptake. We conclude that Cu{sup 2+} reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.

  12. Overexpression of amyloid precursor protein increases copper content in HEK293 cells

    International Nuclear Information System (INIS)

    Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu2+ binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu2+ reduction and 64Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu2+ reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu2+ ions. Moreover, wild-type cells exposed to both Cu2+ ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu2+ reductase activity and increased 64Cu uptake. We conclude that Cu2+ reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.

  13. White matter alterations following thromboembolic stroke: a beta-amyloid precursor protein immunocytochemical study in rats.

    Science.gov (United States)

    Dietrich, W D; Kraydieh, S; Prado, R; Stagliano, N E

    1998-05-01

    Thromboembolic stroke in rats leads to a well-described pattern of histopathological and behavioral abnormalities. However, limited data are available in animal models concerning the response of the white matter to embolic events. The purpose of this study was to document patterns of white matter abnormalities using beta-amyloid precursor protein (betaAPP) immunocytochemistry as a marker of axonal damage. Twelve male Wistar rats underwent photochemically induced right common carotid artery thrombosis (CCAT) or sham procedures. At 3 days after CCAT, rats were perfusion-fixed and sections immunostained for the visualization of betaAPP or stained with hematoxylin and eosin for routine histopathological analysis. As previously described, CCAT produced small ipsilateral embolic infarcts and ischemic cell change within gray matter structures including the medial cerebral cortex, striatum, hippocampus and thalamus. In areas of frank infarction, numerous reactive profiles were observed within borderzones of the damaged site. However, betaAPP immunocytochemistry also revealed reactive axonal profiles within various white matter tracts including the corpus callosum, external capsule and fimbria of the hippocampus. In many cases, the presence of axonal damage could not be appreciated with routine hematoxylin and eosin staining. These data indicate that CCAT leading to platelet embolization to the brain not only produces embolic infarcts but also produces more subtle white matter abnormalities. Previously undetected white matter damage would be expected to participate in the sensorimotor and cognitive behavioral deficits following embolic stroke. PMID:9600599

  14. E22? Mutation in Amyloid ?-Protein Promotes ?-Sheet Transformation, Radical Production, and Synaptotoxicity, But Not Neurotoxicity

    Science.gov (United States)

    Suzuki, Takayuki; Murakami, Kazuma; Izuo, Naotaka; Kume, Toshiaki; Akaike, Akinori; Nagata, Tetsu; Nishizaki, Tomoyuki; Tomiyama, Takami; Takuma, Hiroshi; Mori, Hiroshi; Irie, Kazuhiro

    2011-01-01

    Oligomers of 40- or 42-mer amyloid ?-protein (A?40, A?42) cause cognitive decline and synaptic dysfunction in Alzheimer's disease. We proposed the importance of a turn at Glu22 and Asp23 of A?42 to induce its neurotoxicity through the formation of radicals. Recently, a novel deletion mutant at Glu22 (E22?) of A?42 was reported to accelerate oligomerization and synaptotoxicity. To investigate this mechanism, the effects of the E22? mutation in A?42 and A?40 on the transformation of ?-sheets, radical production, and neurotoxicity were examined. Both mutants promoted ?-sheet transformation and the formation of radicals, while their neurotoxicity was negative. In contrast, E22P-A?42 with a turn at Glu22 and Asp23 exhibited potent neurotoxicity along with the ability to form radicals and potent synaptotoxicity. These data suggest that conformational change in E22?-A? is similar to that in E22P-A?42 but not the same, since E22?-A?42 exhibited no cytotoxicity, unlike E22P-A?42 and wild-type A?42. PMID:21234376

  15. A setup for simultaneous measurement of infrared spectra and light scattering signals: Watching amyloid fibrils grow from intact proteins

    International Nuclear Information System (INIS)

    A setup for the simultaneous measurement of mid-infrared spectra and static light scattering is described that can be used for the analysis of the formation of nanoscale and microscopic aggregates from smaller molecules to biopolymers. It can be easily integrated into sample chambers of infrared spectrometers or combined with laser beams from tunable infrared lasers. Here, its use for the analysis of the formation of amyloid fibrils from intact proteins is demonstrated. The formation of amyloid fibrils or plaques from proteins is a widespread and pathogenetic relevant process, and a number of diseases are caused and correlated with the deposition of amyloid fibrils in cells and tissues. The molecular mechanisms of these transformations, however, are still unclear. We report here the simultaneous measurement of infrared spectra and static light scattering for the analysis of fibril formation from egg-white lysozyme. The transformation of the native form into non-native forms rich in ?-sheet structure is measured by analysis of the amide I spectral region in the infrared spectra, which is sensitive for local structures. At the same time, light scattering signals at forward direction as well as the forward/backward ratio, which are sensitive for the number of scattering centers and their approximate sizes, respectively, are collected for the analysis of fibril growth. Thermodynamic and kinetic parameters as well as mechanistic information are deduced from the combination of the two complementary techniques

  16. A setup for simultaneous measurement of infrared spectra and light scattering signals: Watching amyloid fibrils grow from intact proteins

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yang; Maurer, Jürgen; Roth, Andreas; Vogel, Vitali; Winter, Ernst; Mäntele, Werner, E-mail: maentele@biophysik.uni-frankfurt.de [Institut für Biophysik, Goethe-Universität Frankfurt am Main, Max-von Laue-Straße 1, D-60438 Frankfurt am Main (Germany)

    2014-08-15

    A setup for the simultaneous measurement of mid-infrared spectra and static light scattering is described that can be used for the analysis of the formation of nanoscale and microscopic aggregates from smaller molecules to biopolymers. It can be easily integrated into sample chambers of infrared spectrometers or combined with laser beams from tunable infrared lasers. Here, its use for the analysis of the formation of amyloid fibrils from intact proteins is demonstrated. The formation of amyloid fibrils or plaques from proteins is a widespread and pathogenetic relevant process, and a number of diseases are caused and correlated with the deposition of amyloid fibrils in cells and tissues. The molecular mechanisms of these transformations, however, are still unclear. We report here the simultaneous measurement of infrared spectra and static light scattering for the analysis of fibril formation from egg-white lysozyme. The transformation of the native form into non-native forms rich in ?-sheet structure is measured by analysis of the amide I spectral region in the infrared spectra, which is sensitive for local structures. At the same time, light scattering signals at forward direction as well as the forward/backward ratio, which are sensitive for the number of scattering centers and their approximate sizes, respectively, are collected for the analysis of fibril growth. Thermodynamic and kinetic parameters as well as mechanistic information are deduced from the combination of the two complementary techniques.

  17. Binding of rare earths to serum proteins and DNA

    International Nuclear Information System (INIS)

    In order to investigate further the physiological behavior of rare earths and rare earth chelates, studies of the binding of 46Sc, 91Y, and 140La to serum proteins and to nucleic acids were performed using the methods of equilibrium dialysis and ultrafiltration. The binding of lanthanum and yttrium as the chlorides to ?-globulin increased as the free rare earth concentration increased. When scandium and lanthanum were chelated in nitrilotriacetate (NTA) the binding to ?-globulin was considerably less and there was no binding to albumin. The binding of 46Sc chelated to ethylenediamine di(O-hydroxyphenylacetate) (EDDHA) was five times greater than of 46Sc chloride. When the free scandium concentration was increased, the moles bound per mole of protein increased proportionally and the binding was reversible. Scandium was 100% filterable from a mixture of human serum and from the scandium chelates with high stability constants scandium diethylenetriaminepentaacetate (ScDTPA), scandium ethylenediaminetetraacetate (ScEDTA) and scandium cyclohexane trans-1,2-diaminetetraacetate (ScCDTA) respectively. In contrast, only 2% of the scandium was filterable when scandium nitrilotriacetate, a scandium chelate of low stability constant, was used. (Auth.)

  18. Effects of cerebrovascular disease on amyloid precursor protein metabolites in cerebrospinal fluid

    Directory of Open Access Journals (Sweden)

    Rosengren Lars

    2010-07-01

    Full Text Available Abstract Background Alzheimer's disease (AD and cerebrovascular disease (CVD including chronic small vessel disease of the brain (SVD are the most frequent causes of dementia. AD is associated with metabolism of amyloid precursor protein (APP and low levels of amyloid-? peptide (A? X-42 in the cerebrospinal fluid (CSF. CVD and SVD are established risk factors for AD, brain white matter lesions (WML are established surrogate markers for SVD and are also associated with reduced CSF A?X-42. A cohort survey was performed to examine whether SVD or acute CVD affects APP metabolism and to explore a potential association between WML and APP metabolism in two groups; cognitively impaired patients, subjective and mild (SCI and MCI and stroke patients. Through measurements of CSF APP metabolite levels in patients with a wide range of WML volumes, this study aimed to determine how SVD influences APP metabolism. Methods Sixty-three patients were included: 37 with subjective cognitive impairment (SCI or mild cognitive impairment (MCI without stroke, and 26 after acute stroke. Chronic and acute WML volume and infarct volume were determined by magnetic resonance imaging (MRI post-scan processing, and CSF levels of ?- and ?-cleaved soluble APP (sAPP-? and sAPP-?, A?X-38, A?X-40 and A?X-42 were determined. The Mann-Whitney test was used to compare the patient groups. Chronic and acute WML volumes, infarct volume, age, and sex were used as predictors for CSF biomarker levels in linear regression analysis. Results CSF levels of sAPP-? and sAPP-? were strongly correlated (r = 0.95, p p p p ? 0.005; p ? 0.01; p ? 0.01; p ? 0.05; p ? 0.05 respectively, but not with acute WML or infarct volumes. Conclusions Lower CSF levels of sAPP-? and sAPP-? in the stroke group than in the SCI/MCI group and an inverse correlation with chronic WML indicate that ischemia lowers the levels of CSF sAPP metabolites and suggests that APP axonal transport or metabolism may be affected in SVD of the brain.

  19. Exclusively targeting ?-secretase to lipid rafts by GPI-anchor addition up-regulates ?-site processing of the amyloid precursor protein

    OpenAIRE

    Cordy, Joanna M; Hussain, Ishrut; Dingwall, Colin; Hooper, Nigel M.; Turner, Anthony J.

    2003-01-01

    ?-Secretase (BACE, Asp-2) is a transmembrane aspartic proteinase responsible for cleaving the amyloid precursor protein (APP) to generate the soluble ectodomain sAPP? and its C-terminal fragment CTF?. CTF? is subsequently cleaved by ?-secretase to produce the neurotoxic/synaptotoxic amyloid-? peptide (A?) that accumulates in Alzheimer's disease. Indirect evidence has suggested that amyloidogenic APP processing may preferentially occur in lipid rafts. Here, we show that relatively little wild-...

  20. Amyloid Beta-Mediated Epigenetic Alteration of Insulin-Like Growth Factor Binding Protein 3 Controls Cell Survival in Alzheimer's Disease

    OpenAIRE

    Sung, Hye Youn; Choi, Eun Nam; Lyu, Dahyun; Mook-Jung, Inhee; Ahn, Jung-Hyuck

    2014-01-01

    Swedish double mutation (KM670/671NL) of amyloid precursor protein (APP) is reported to increase toxic amyloid ? (A?) production via aberrant cleavage at the ?-secretase site and thereby cause early-onset Alzheimer's disease (AD). However, the underlying molecular mechanisms leading to AD pathogenesis remains largely unknown. Previously, our transcriptome sequence analyses revealed global expressional modifications of over 600 genes in APP-Swedish mutant-expressing H4 (H4-sw) cells compared t...

  1. On the transfer of serum proteins to the rat intestinal juice

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Norén, Ove; Poulsen, Mona D; Sjöström, H; Hansen, Gert Helge; Olsen, Jørgen

    1994-01-01

    The in vivo pattern of serum proteins in the rat small-intestinal juice was characterized by crossed immunoelectrophoresis. Immunoglobulins and albumin, alpha-1-antitrypsin, transferrin, and orosomucoid were present. Larger serum proteins were absent (ceruloplasmin, haptoglobin, alpha-1-macroglobulin, alpha and beta lipoproteins). Thus, apart from immunoglobulins, only serum proteins with a molecular mass less than approximately 100 kDa were demonstrated. The origin and epithelial transfer were ...

  2. Yolk sac endoderm: exclusive site of serum protein synthesis in the early chick embryo

    International Nuclear Information System (INIS)

    In order to determine which cell type or types synthesized serum proteins, yolk sacs from 4-day chick embryos were manually separated into ectoderm, mesoderm, and endoderm and incubated in the presence of radioactive valine. Analysis of the incubation media by polyacrylamide gel electrophoresis as well as by immunoprecipitation showed that all serum proteins were synthesized exclusively by the cells of the endoderm. These included transferrin and three embryo-specific serum proteins: ?reverse arrowglobulin ?-globulin b, and prealbumin

  3. Neural stem cells isolated from amyloid precursor protein-mutated mice for drug discovery

    Directory of Open Access Journals (Sweden)

    Vito Antonio Baldassarro

    2013-01-01

    Full Text Available AIM: To develop an in vitro model based on neural stem cells derived from transgenic animals, to be used in the study of pathological mechanisms of Alzheimer’s disease and for testing new molecules. METHODS: Neural stem cells (NSCs were isolated from the subventricular zone of Wild type (Wt and Tg2576 mice. Primary and secondary neurosphere generation was studied, analysing population doubling and the cell yield per animal. Secondary neurospheres were dissociated and plated on MCM Gel Cultrex 2D and after 6 d in vitro (DIVs in mitogen withdrawal conditions, spontaneous differentiation was studied using specific neural markers (MAP2 and TuJ-1 for neurons, GFAP for astroglial cells and CNPase for oligodendrocytes. Gene expression pathways were analysed in secondary neurospheres, using the QIAGEN PCR array for neurogenesis, comparing the Tg2576 derived cell expression with the Wt cells. Proteins encoded by the altered genes were clustered using STRING web software. RESULTS: As revealed by 6E10 positive staining, all Tg2576 derived cells retain the expression of the human transgenic Amyloid Precursor Protein. Tg2576 derived primary neurospheres show a decrease in population doubling. Morphological analysis of differentiated NSCs reveals a decrease in MAP2- and an increase in GFAP-positive cells in Tg2576 derived cells. Analysing the branching of TuJ-1 positive cells, a clear decrease in neurite number and length is observed in Tg2576 cells. The gene expression neurogenesis pathway revealed 11 altered genes in Tg2576 NSCs compared to Wt. CONCLUSION: Tg2576 NSCs represent an appropriate AD in vitro model resembling some cellular alterations observed in vivo, both as stem and differentiated cells.

  4. The conjugation of amyloid beta protein on the gold colloidal nanoparticles' surfaces

    International Nuclear Information System (INIS)

    The conjugation of various sequences of amyloid ? protein solution (A?); A?1-11, A?12-28, A?31-35, A?1-40, and A?1-42 with gold colloidal suspension of 20 nm size was examined. Absorption spectroscopy was utilized to identify changes in the optical properties of gold colloid for pHs, ranging from pH 2 to pH 10. Colour changes were seen for all tested proteins in this study at a higher pH than where bare gold colloid exhibits its colour change at pH = 3.09 ± 0.02. All tested A? sequences except for A?1-42 exhibited colour changes around pI values of A?1-40, about pH 5.2. The A?1-42 exhibited precipitants in all pH lower than pH 7 and showed the colour change around pH 3.96 ± 0.05. The colour change observed at a pH lower than 5 is attributed to the unfolded A? monomer units around the gold colloidal surface. Interestingly, only A?1-40-coated gold colloidal nanoparticles exhibited a reversible colour change as the pH was externally altered between pH 4 and 10. This reversibility is an important implication of the observation of a reversible step reported for the fibrillogenesis. It was interpreted that the reversible process takes place when hydrophilic A? possesses a three-dimensional network containing both ?-sheet and ?-helices

  5. Regulated O-glycosylation of the Alzheimer beta-A4 amyloid precursor protein in thyrocytes.

    Science.gov (United States)

    Graebert, K S; Popp, G M; Kehle, T; Herzog, V

    1995-01-01

    In thyrocytes, the beta-amyloid precursor protein (beta-APP) is expressed, proteolytically cleaved and released into the extracellular space in a TSH-dependent fashion. Immunocytochemically, beta-APP was detectable mainly in the stacked Golgi cisternae indicating the accumulation in this organelle. Because this unusual immunoreactivity might be related to the Golgi-specific posttranslational processing we studied the glycosylation of beta-APP and the possible regulation of this process. For this purpose we used FRTL-5 cells which showed that the degree of glycosylation was also TSH dependent. Glycosidase digestion experiments revealed that only the O-glycans, not the N-glycans, of beta-APP were regulated by TSH. Using enzyme digestion and lectin precipitation analyses we showed that O-glycosylation involved mainly alpha 2,6-sialylated Gal 1-3 GalNAc-alpha-core glycans (approximately 85%) whereas the 2,3 linked sialic acids amounted to only approximately 15% of total sialic acid residues. Upon stimulation with TSH, O-glycosylation as measured by the degree of sialylation increased by a factor of approximately 1.7 thereby raising the molecular mass of mature beta-APP by 4 to 5 kDa above that from control cells. This process coincided with the accumulation of a proteolytically derived 8.5 kDa C-terminal beta-APP fragment indicating that the proteolytic processing of mature beta-APP was not inhibited by its O-glycosylation. When cells were stimulated with TSH in the presence of cycloheximide, the Golgi cisternae lost their predominant immunoreactivity for beta-APP and were rapidly emptied (within 30 min). Hence, under the conditions of normal protein synthesis, the Golgi cisternae may operate as a storage compartment for beta-APP. PMID:7750518

  6. Macroautophagy is not directly involved in the metabolism of amyloid precursor protein.

    Science.gov (United States)

    Boland, Barry; Smith, David A; Mooney, Declan; Jung, Sonia S; Walsh, Dominic M; Platt, Frances M

    2010-11-26

    Alterations in the metabolism of amyloid precursor protein (APP) are believed to play a central role in Alzheimer disease pathogenesis. Burgeoning data indicate that APP is proteolytically processed in endosomal-autophagic-lysosomal compartments. In this study, we used both in vivo and in vitro paradigms to determine whether alterations in macroautophagy affect APP metabolism. Three mouse models of glycosphingolipid storage diseases, namely Niemann-Pick type C1, GM1 gangliosidosis, and Sandhoff disease, had mTOR-independent increases in the autophagic vacuole (AV)-associated protein, LC3-II, indicative of impaired lysosomal flux. APP C-terminal fragments (APP-CTFs) were also increased in brains of the three mouse models; however, discrepancies between LC3-II and APP-CTFs were seen between primary (GM1 gangliosidosis and Sandhoff disease) and secondary (Niemann-Pick type C1) lysosomal storage models. APP-CTFs were proportionately higher than LC3-II in cerebellar regions of GM1 gangliosidosis and Sandhoff disease, although LC3-II increased before APP-CTFs in brains of NPC1 mice. Endogenous murine A?40 from RIPA-soluble extracts was increased in brains of all three mice. The in vivo relationship between AV and APP-CTF accumulation was also seen in cultured neurons treated with agents that impair primary (chloroquine and leupeptin + pepstatin) and secondary (U18666A and vinblastine) lysosomal flux. However, A? secretion was unaffected by agents that induced autophagy (rapamycin) or impaired AV clearance, and LC3-II-positive AVs predominantly co-localized with degradative LAMP-1-positive lysosomes. These data suggest that neuronal macroautophagy does not directly regulate APP metabolism but highlights the important anti-amyloidogenic role of lysosomal proteolysis in post-secretase APP-CTF catabolism. PMID:20864542

  7. Self-assembly of a nine-residue amyloid-forming peptide fragment of SARS corona virus E-protein: mechanism of self aggregation and amyloid-inhibition of hIAPP.

    Science.gov (United States)

    Ghosh, Anirban; Pithadia, Amit S; Bhat, Jyotsna; Bera, Supriyo; Midya, Anupam; Fierke, Carol A; Ramamoorthy, Ayyalusamy; Bhunia, Anirban

    2015-04-01

    Molecular self-assembly, a phenomenon widely observed in nature, has been exploited through organic molecules, proteins, DNA, and peptides to study complex biological systems. These self-assembly systems may also be used in understanding the molecular and structural biology which can inspire the design and synthesis of increasingly complex biomaterials. Specifically, use of these building blocks to investigate protein folding and misfolding has been of particular value since it can provide tremendous insights into peptide aggregation related to a variety of protein misfolding diseases, or amyloid diseases (e.g., Alzheimer's disease, Parkinson's disease, type-II diabetes). Herein, the self-assembly of TK9, a nine-residue peptide of the extra membrane C-terminal tail of the SARS corona virus envelope, and its variants were characterized through biophysical, spectroscopic, and simulated studies, and it was confirmed that the structure of these peptides influences their aggregation propensity, hence, mimicking amyloid proteins. TK9, which forms a beta-sheet rich fibril, contains a key sequence motif that may be critical for beta-sheet formation, thus making it an interesting system to study amyloid fibrillation. TK9 aggregates were further examined through simulations to evaluate the possible intra- and interpeptide interactions at the molecular level. These self-assembly peptides can also serve as amyloid inhibitors through hydrophobic and electrophilic recognition interactions. Our results show that TK9 inhibits the fibrillation of hIAPP, a 37 amino acid peptide implicated in the pathology of type-II diabetes. Thus, biophysical and NMR experimental results have revealed a molecular level understanding of peptide folding events, as well as the inhibition of amyloid-protein aggregation are reported. PMID:25785896

  8. ALTERATIONS IN TOTAL PROTEIN CONCENTRATION, SERUM PROTEIN FRACTIONS AND ALBUMIN/GLOBULIN RATIO IN HEALTHY RABBITS

    OpenAIRE

    Nuzhat Sultana; Rahila Najam

    2013-01-01

    This study assessed the effect of oral administration of Aloe vera and was to evaluate total serum protein, albumin and globulin concentrations as well as albumin / globulin (A / G) ratio. Twenty rabbits weighing 1000 – 1800 g were divided into 2 groups. Each group consisted of ten animals. One served as control and other group served as experimental group. Results show that animals after 07, 15 and 30 days dosing of Aloe vera showed highly significant decrease in total protein and globulin a...

  9. Polyglutamine-Rich Suppressors of Huntingtin Toxicity Act Upstream of Hsp70 and Sti1 in Spatial Quality Control of Amyloid-Like Proteins

    OpenAIRE

    Wolfe, K.J.; Ren, H.Y.; Trepte, P.; Cyr, D M

    2014-01-01

    Protein conformational maladies such as Huntington Disease are characterized by accumulation of intracellular and extracellular protein inclusions containing amyloid-like proteins. There is an inverse correlation between proteotoxicity and aggregation, so facilitated protein aggregation appears cytoprotective. To define mechanisms for protective protein aggregation, a screen for suppressors of nuclear huntingtin (Htt103Q) toxicity was conducted. Nuclear Htt103Q is highly toxic and less aggreg...

  10. The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells

    International Nuclear Information System (INIS)

    Highlights: • Copper levels are elevated in the tumour microenvironment. • APP mitigates copper-induced growth inhibition of DU145 prostate cancer (PCa) cells. • The APP intracellular domain is a prerequisite; soluble forms have no effect. • The E1 CuBD of APP is also a prerequisite. • APP copper binding potentially mitigates copper-induced PCa cell growth inhibition. - Abstract: Copper plays an important role in the aetiology and growth of tumours and levels of the metal are increased in the serum and tumour tissue of patients affected by a range of cancers including prostate cancer (PCa). The molecular mechanisms that enable cancer cells to proliferate in the presence of elevated copper levels are, therefore, of key importance in our understanding of tumour growth progression. In the current study, we have examined the role played by the amyloid precursor protein (APP) in mitigating copper-induced growth inhibition of the PCa cell line, DU145. A range of APP molecular constructs were stably over-expressed in DU145 cells and their effects on cell proliferation in the presence of copper were monitored. Our results show that endogenous APP expression was induced by sub-toxic copper concentrations in DU145 cells and over-expression of the wild-type protein was able to mitigate copper-induced growth inhibition via a mechanism involving the cytosolic and E1 copper binding domains of the full-length protein. APP likely represents one of a range of copper binding proteins that PCa cells employ in order to ensure efficient proliferation despite elevated concentrations of the metal within the tumour microenvironment. Targeting the expression of such proteins may contribute to therapeutic strategies for the treatment of cancers

  11. Electrophoretic pattern of serum proteins in horses with babesiosis Patrón electroforético de proteínas séricas en caballos con babesiosis

    OpenAIRE

    Barrera, R.; MV Carapeto; MA Habela; Zaragoza, C.

    2010-01-01

    Serum electrophoresis in cellulose acetate strips is a technique commonly used to separate the protein fractions. This technique allows detecting quantitative and qualitative changes in the serum proteins associated with different diseases. The aim of this study was to characterize the changes of the serum protein fractions produced in horses suffering from babesiosis and to evaluate its application in its diagnosis. Serum total proteins were calculated and the serum electrophoresis from 53 h...

  12. LDLR-related protein 10 (LRP10) regulates amyloid precursor protein (APP) trafficking and processing: evidence for a role in Alzheimer’s disease

    OpenAIRE

    Brodeur Julie; Thériault Caroline; Lessard-Beaudoin Mélissa; Marcil Alexandre; Dahan Sophie; Lavoie Christine

    2012-01-01

    Abstract Background The A? peptide that accumulates in Alzheimer’s disease (AD) is derived from amyloid precursor protein (APP) following proteolysis by ?- and ?-secretases. Substantial evidence indicates that alterations in APP trafficking within the secretory and endocytic pathways directly impact the interaction of APP with these secretases and subsequent A? production. Various members of the low-density lipoprotein receptor (LDLR) family have been reported to play a role in APP traffickin...

  13. Serum transferrin levels in children with protein-energy malnutrition

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    Selime Aydo?du

    2013-03-01

    Full Text Available Objective: Although the diagnosis of patients with severemalnutrition is easy, it is very difficult to recognize patientswith mild and moderate malnutrition. A variety of methodsattempts to develop for early diagnosis of these cases.In this study, we evaluated the serum transferrin and albuminlevels in children with mild, moderate and severeprotein-energy malnutrition (PEM.Materials and methods: Children admitted to our policlinic,aged between 3 and 25 months, 45 subjects withPEM and 39 healthy subjects (control group were evaluated.According to the Gomez, Waterlow and Kanawatisubjects with PEM were divided in 3 subgroups mild,moderate and severe PEM. Anthropometric measurementsand biochemical results of 4 groups were compared.Results: For albumin levels in mild to moderate PEMgroups, 37.7% sensitivity, and 28.5% specificity, positivepredictive value 54%; negative predictive value 16.6%was found. For severe PEM sensitivity, specificity, positivepredictive value and negative predictive value were71%, 62.5%, 45%, and 83.3% respectively.With respect to the levels of transferrin, a significant differencewas found between mild PEM-control and moderatePEM-control groups (p0.05.Conclusion: Our study results showed that albumin isa weak indicator in mild-moderate PEM. In these cases,serum transferrin level reduces before decreasing of albuminlevel, thus it may be an early sensitive finding thatcan be used as a sensitive parameter in the diagnosis ofearly stages of malnutrition.Key words: Protein energy malnutrition, children, albumin,transferrin

  14. Influence of chlorpyrifos oxon on the development and progression of Alzheimer's disease in amyloid precursor protein transgenic mice

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    Jin Yu

    2015-03-01

    Full Text Available Aim: Alzheimer's disease (AD is a devastating neurological disorder and the most common form of dementia. Until date, the cause of AD eludes us, but a number of hypotheses have been put forward to try and understand the mechanisms involved. A series of studies have indicated that environmental factors, such as pesticides, heavy metals, and others can contribute to the development and progression of AD. Based on these data, we determined the impact of pesticides (chlorpyrifos oxon [CPO] on AD-like pathogenesis in amyloid precursor protein (APP transgenic mice. Methods: APP mice were treated at various times with low-dose CPO (1 mg/kg/day, in utero (3-week of gestation, during lactation (3-week, or as young adults (continuous dosing. Results: Exposure to CPO at all times enhanced neuro-inflammation and exacerbated oxidative stress in the brain prior to amyloid deposition. CPO-treated APP mice showed a decrease in memory and learning compared with untreated APP mice; furthermore, analyses of brain tissue sections and extracts showed an increase in Ab levels and C-terminal fragment-b levels, a decrease in soluble APPa (sAPPa levels, and an increase in plaque load. In addition, CPO-treated APP transgenic mice showed a significant decrease in neurotrophic factor levels (nerve growth factor, brain-derived neurotrophic factor, and neurotrophin-3 compared to vehicle-treated APP transgenic animals. Treatment with galantamine attenuated the effects of CPO by reducing amyloid b levels and amyloid load. Conclusion: CPO accelerated and exacerbated the disease development and progression in the APP mice suggesting that pesticides may play a significant role in the pathogenesis of AD.

  15. The prion protein ligand, stress-inducible phosphoprotein 1, regulates amyloid-? oligomer toxicity.

    Science.gov (United States)

    Ostapchenko, Valeriy G; Beraldo, Flavio H; Mohammad, Amro H; Xie, Yu-Feng; Hirata, Pedro H F; Magalhaes, Ana C; Lamour, Guillaume; Li, Hongbin; Maciejewski, Andrzej; Belrose, Jillian C; Teixeira, Bianca L; Fahnestock, Margaret; Ferreira, Sergio T; Cashman, Neil R; Hajj, Glaucia N M; Jackson, Michael F; Choy, Wing-Yiu; MacDonald, John F; Martins, Vilma R; Prado, Vania F; Prado, Marco A M

    2013-10-16

    In Alzheimer's disease (AD), soluble amyloid-? oligomers (A?Os) trigger neurotoxic signaling, at least partially, via the cellular prion protein (PrP(C)). However, it is unknown whether other ligands of PrP(C) can regulate this potentially toxic interaction. Stress-inducible phosphoprotein 1 (STI1), an Hsp90 cochaperone secreted by astrocytes, binds to PrP(C) in the vicinity of the A?O binding site to protect neurons against toxic stimuli. Here, we investigated a potential role of STI1 in A?O toxicity. We confirmed the specific binding of A?Os and STI1 to the PrP and showed that STI1 efficiently inhibited A?O binding to PrP in vitro (IC50 of ?70 nm) and also decreased A?O binding to cultured mouse primary hippocampal neurons. Treatment with STI1 prevented A?O-induced synaptic loss and neuronal death in mouse cultured neurons and long-term potentiation inhibition in mouse hippocampal slices. Interestingly, STI1-haploinsufficient neurons were more sensitive to A?O-induced cell death and could be rescued by treatment with recombinant STI1. Noteworthy, both A?O binding to PrP(C) and PrP(C)-dependent A?O toxicity were inhibited by TPR2A, the PrP(C)-interacting domain of STI1. Additionally, PrP(C)-STI1 engagement activated ?7 nicotinic acetylcholine receptors, which participated in neuroprotection against A?O-induced toxicity. We found an age-dependent upregulation of cortical STI1 in the APPswe/PS1dE9 mouse model of AD and in the brains of AD-affected individuals, suggesting a compensatory response. Our findings reveal a previously unrecognized role of the PrP(C) ligand STI1 in protecting neurons in AD and suggest a novel pathway that may help to offset A?O-induced toxicity. PMID:24133259

  16. Smoking and lung cancer-induced changes in N-glycosylation of blood serum proteins

    OpenAIRE

    Vasseur, Jacqueline A; Goetz, John A; Alley, William R.; Novotny, Milos V

    2012-01-01

    Glycosylation is a key post-translational protein modification which appears important in malignant transformation and tumor metastasis. Abnormal glycosylation of different proteins can often be measured in the blood serum. In this study, we extend our serum-based structural investigations to samples provided by patients diagnosed with lung cancer, paying particular attention to the effects of smoking on the serum glycomic traces. Following a battery of glycomic tests, we find that several fu...

  17. Induction of methionine-sulfoxide reductases protects neurons from amyloid ?-protein insults in vitro and in vivo

    OpenAIRE

    Moskovitz, Jackob; Maiti, Panchanan; Lopes, Dahabada H. J.; Oien, Derek B.; Attar, Aida; Liu, Tingyu; Mittal, Shivina; Hayes, Jane; Bitan, Gal

    2011-01-01

    Amyloid ?-protein (A?) self-assembly into toxic oligomers and fibrillar polymers is believed to cause Alzheimer’s disease (AD). In the AD brain, a high percentage of A? contains Met-sulfoxide at position 35, though the role this modification plays in AD is not clear. Oxidation of Met35 to sulfoxide has been reported to decrease A? assembly and neurotoxicity, whereas surprisingly, Met35 oxidation to sulfone yields similar toxicity to unoxidized A?. We hypothesized that the lower toxicity of A?...

  18. Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1?, suppress amyloid ?-induced neurotoxicity

    International Nuclear Information System (INIS)

    Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-? (A?). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1? (SDF-1?), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A?-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1? significantly protected neurons from A?-induced dendritic regression and apoptosis in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1?. Intra-cerebroventricular (ICV) injection of A? led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A?-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F2-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1?. Additionally, MIP-2 or SDF-1? was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A? neurotoxicity in CXCR2?/? mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: ? Neuroprotective ability of the chemokines MIP2 and CXCL12 against A? toxicity. ? MIP-2 or CXCL12 prevented dendritic regression and apoptosis in vitro. ? Neuroprotection through activation of Akt, ERK1/2 and maintenance of ADAM17. ? Neuroprotection of hippocampal pyramidal neurons in vivo by MIP-2 or CXCL12. ? MIP-2 or CXCL12 prevent elevation of F2-Isoprostanes against A? treatment.

  19. Memantine treatment decreases levels of secreted Alzheimer’s amyloid precursor protein (APP) and amyloid beta (A?) peptide in the human neuroblastoma cells

    OpenAIRE

    Ray, Balmiki; Banerjee, Pradeep K; Greig, Nigel H.; Lahiri, Debomoy K.

    2009-01-01

    Memantine, an uncompetitive NMDA receptor antagonist, is a FDA approved drug used for the treatment of moderate to severe Alzheimer’s disease (AD). Several studies have documented protective roles of memantine against amyloid beta peptide (A?)– mediated damage to neurons in both in vitro and in vivo models. Memantine is also effective in reducing amyloid burden in the brain of APP transgenic mice. Currently the role of memantine in the A?– mediated neurodegenerative cascade, including APP met...

  20. Serum amyloid A stimulates matrix-metalloproteinase-9 upregulation via formyl peptide receptor like-1-mediated signaling in human monocytic cells

    International Nuclear Information System (INIS)

    In the present study, we found that serum amyloid A (SAA) stimulated matrix-metalloproteinase-9 (MMP-9) upregulation at the transcription and translational levels in THP-1 cells. SAA stimulated the activation of nuclear factor ?B (NF-?B), which was required for the MMP-9 upregulation by SAA. The signaling events induced by SAA included the activation of ERK and intracellular calcium rise, which were found to be required for MMP-9 upregulation. Formyl peptide receptor like 1 (FPRL1) was found to be involved in the upregulation of MMP-9 by SAA. Among several FPRL1 agonists, including Trp-Lys-Tyr-Met-Val-D-Met (WKYMVm), SAA selectively stimulated MMP-9 upregulation. With respect to the molecular mechanisms involved in the differential action of SAA and WKYMVm, we found that SAA could not competitively inhibit the binding of 125I-labeled WKYMVm to FPRL1. Taken together, we suggest that SAA plays a role in the modulation of inflammatory and immune responses via FPRL1, by inducing MMP-9 upregulation in human monocytic cells

  1. The neuroprotective effect of immune serum of adeno-associated virus vaccine containing A?1-15 gene on amyloid toxicity

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    Ling-Yun Liu

    2013-01-01

    Full Text Available Objective: The aim of this study was to explore the effect of adeno-associated virus (AAV serotype 2 vector vaccine containing amyloid-? peptide (A? 1-15 gene fragment (AAV-A?15 immunized mice sera on counteracting A?1-42 peptide toxicity towards a primary culture cortical neurons. Materials and Methods: BALB/c mice were vaccinated via the intramuscular immunization route with AAV-A?15. The anti-A? antibody titer of immunized mice sera was quantified by sandwich Enzyme-Linked ImmunoSorbent Assay. The toxicity of A?1-42 peptide on neurons was assessed by morphology with an inverse microscopy and cell viability was determined by the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT assay. Results: AAV-A?15 could induce an A?-specific immunoglobulin G (IgG humoral immune response in /c mice the anti-A? antibodies were detectable at 1 month after immunization, significantly increased at 2 and 4 months after immunization, and the immunized sera could attenuate cytotoxicity of A?1-42 peptide on primary culture cortical neurons. Conclusions: The immune serum of AAV-A?15 could play a neuroprotective effect against A?1-42 peptide toxicity, which would be beneficial for Alzheimer?s disease patients.

  2. Nanoparticle-Assisted Removal of Protein in Human Serum for Metabolomics Studies.

    Science.gov (United States)

    Zhang, Bo; Xie, Mouzhe; Bruschweiler-Li, Lei; Brüschweiler, Rafael

    2016-01-01

    Among human body fluids, serum plays a key role for diagnostic tests and, increasingly, for metabolomics analysis. However, the high protein content of serum poses significant challenges for nuclear magnetic resonance (NMR)-based metabolomics studies because it can strongly interfere with metabolite signal detection and quantitation. Although several methods for protein removal have been proposed, including ultrafiltration and organic-solvent-induced protein precipitation, there is currently no standard operating procedure for the elimination of protein from human serum samples. Here, we introduce novel procedures for the removal of protein from serum by the addition of nanoparticles. It is demonstrated how serum protein can be efficiently, cost-effectively, and environmentally friendly removed at physiological pH (pH 7.4) through attractive interactions with silica nanoparticles. It is further shown how serum can be processed with nanoparticles prior to ultrafiltration or organic-solvent-induced protein precipitation for optimal protein removal. After examination of all of the procedures, the combination of nanoparticle treatment and ultrafiltration is found to have a minimal effect on the metabolite content, leading to remarkably clean homo- and heteronuclear NMR spectra of the serum metabolome that compare favorably to other methods for protein removal. PMID:26605638

  3. Structural analysis and characterization of new small serum proteins from the serum of a venomous snake (Gloydius blomhoffii).

    Science.gov (United States)

    Shioi, Narumi; Deshimaru, Masanobu; Terada, Shigeyuki

    2014-01-01

    Some snakes have several anti-toxic proteins in their sera that neutralize their own venom. Five new small serum proteins (SSPs) were isolated from Japanese mamushi (Gloydius blomhoffii) serum by gel-filtration and RP-HPLC, and their N-Terminal sequences were determined. The amino acid sequences of the precursor proteins were deduced from the nucleotide sequences of cDNAs encoding them. Due to the sequence similarity to those of SSPs in habu snake (Protobothrops flavoviridis) serum (>75% identity), these proteins were designated mSSP-1 to mSSP-5 as the homologs of habu proteins. mSSP-1 was stable at 100?°C and in the pH range of 1-10, and inhibited the proteolytic activity of a certain snake venom metalloproteinase. The inhibitory activity was extinguished by modifying the amino groups of mSSP-1. mSSP-1 is the first prostate secretory protein of the 94 amino acid-family protein with a carbohydrate chain in the Asn37 residue. PMID:25036827

  4. Differential effects of interleukin-1? and S100B on amyloid precursor protein in rat retinal neurons

    Directory of Open Access Journals (Sweden)

    Peter JB Anderson

    2009-02-01

    Full Text Available Peter JB Anderson1, Helena R Watts1, Sheila Jen1, Stephen M Gentleman2, Juliet A Moncaster1, et al1Department of Cellular and Molecular Neuroscience and 2Department of Clinical Neuroscience, Division of Neuroscience and Mental Health, Imperial College London, Burlington Danes Building, Hammersmith Hospital, London, UKPurpose: Interleukin-1? (IL-1? and S100B calcium binding protein B (S100B have been implicated in the pathogenesis of Alzheimer’s disease. Both are present in and around senile plaques and have been shown to increase levels of amyloid precursor protein (APP mRNA in vitro. However, it is not known how either of these substances affects APP in vivo.Methods: We have studied the effects of IL-1? and S100B on the expression and processing of APP using a retinal-vitreal model. We have also investigated the effect of amyloid beta peptide (A? on APP in the same system and the regulation of S100B production by A? and IL-1? from retinal glial cells.Results: Retinal ganglion cells constitutively express APP. However, after intravitreal injection of IL-1? or A? there was a marked reduction in APP levels as detected by Western blotting and IL-1? produced a decrease in APP immunoreactivity (IR. Nissl staining showed that the integrity of the injected retinas was unchanged after injection. Two days after S100B injection, there was a small reduction in APP-IR but this was accompanied by the appearance of some intensely stained large ganglion cells and there was some up-regulation in APP holoprotein  levels on Western blot. Seven days post-S100? injection, these large, highly stained cells had increased in number throughout the retina. Injection of A? and IL-1? also caused an increase in S100B production within the retinal Müller glial cells.Conclusion: These results support the hypothesis that S100B (a glial-derived neurotrophic factor and IL-1? (a pro-infl ammatory cytokine can modulate the expression and processing of APP in vivo and so may contribute to the progression of Alzheimer’s disease.Keywords: Alzheimer’s disease, interleukin 1?, S100B, amyloid precursor protein, amyloid-?, retina

  5. Evaluation of three high abundance protein depletion kits for umbilical cord serum proteomics

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    Nie Jing

    2011-05-01

    Full Text Available Abstract Background High abundance protein depletion is a major challenge in the study of serum/plasma proteomics. Prior to this study, most commercially available kits for depletion of highly abundant proteins had only been tested and evaluated in adult serum/plasma, while the depletion efficiency on umbilical cord serum/plasma had not been clarified. Structural differences between some adult and fetal proteins (such as albumin make it likely that depletion approaches for adult and umbilical cord serum/plasma will be variable. Therefore, the primary purposes of the present study are to investigate the efficiencies of several commonly-used commercial kits during high abundance protein depletion from umbilical cord serum and to determine which kit yields the most effective and reproducible results for further proteomics research on umbilical cord serum. Results The immunoaffinity based kits (PROTIA-Sigma and 5185-Agilent displayed higher depletion efficiency than the immobilized dye based kit (PROTBA-Sigma in umbilical cord serum samples. Both the PROTIA-Sigma and 5185-Agilent kit maintained high depletion efficiency when used three consecutive times. Depletion by the PROTIA-Sigma Kit improved 2DE gel quality by reducing smeared bands produced by the presence of high abundance proteins and increasing the intensity of other protein spots. During image analysis using the identical detection parameters, 411 ± 18 spots were detected in crude serum gels, while 757 ± 43 spots were detected in depleted serum gels. Eight spots unique to depleted serum gels were identified by MALDI- TOF/TOF MS, seven of which were low abundance proteins. Conclusions The immunoaffinity based kits exceeded the immobilized dye based kit in high abundance protein depletion of umbilical cord serum samples and dramatically improved 2DE gel quality for detection of trace biomarkers.

  6. Overcoming antigen masking of anti-amyloidbeta antibodies reveals breaking of B cell tolerance by virus-like particles in amyloidbeta immunized amyloid precursor protein transgenic mice

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    Ugen Kenneth E

    2004-06-01

    Full Text Available Abstract Background In prior work we detected reduced anti-A? antibody titers in A?-vaccinated transgenic mice expressing the human amyloid precursor protein (APP compared to nontransgenic littermates. We investigated this observation further by vaccinating APP and nontransgenic mice with either the wild-type human A? peptide, an A? peptide containing the "Dutch Mutation", E22Q, or a wild-type A? peptide conjugated to papillomavirus virus-like particles (VLPs. Results Anti-A? antibody titers were lower in vaccinated APP than nontransgenic mice even when vaccinated with the highly immunogenic A? E22Q. One concern was that human A? derived from the APP transgene might mask anti-A? antibodies in APP mice. To test this possibility, we dissociated antigen-antibody complexes by incubation at low pH. The low pH incubation increased the anti-A? antibody titers 20–40 fold in APP mice but had no effect in sera from nontransgenic mice. However, even after dissociation, the anti-A? titers were still lower in transgenic mice vaccinated with wild-type A? or E22Q A? relative to non-transgenic mice. Importantly, the dissociated anti-A? titers were equivalent in nontransgenic and APP mice after VLP-based vaccination. Control experiments demonstrated that after acid-dissociation, the increased antibody titer did not cross react with bovine serum albumin nor alpha-synuclein, and addition of A? back to the dissociated serum blocked the increase in antibody titers. Conclusions Circulating human A? can interfere with ELISA assay measurements of anti-A? titers. The E22Q A? peptide vaccine is more immunogenic than the wild-type peptide. Unlike peptide vaccines, VLP-based vaccines against A? abrogate the effects of A? self-tolerance.

  7. Role of maternal serum Chlamydia trachomatis IgG antibodies and serum C- reactive protein in preterm labour

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    Preeti Dubey

    2014-02-01

    Conclusion: The detection of maternal serum C- reactive protein and antichlamydial antibodies are valuable, non-invasive diagnostic procedure for prediction of preterm delivery and can be used as predictors of preterm delivery. [Int J Reprod Contracept Obstet Gynecol 2014; 3(1.000: 195-198

  8. Amyloid precursor protein regulates neurogenesis by antagonizing miR-574-5p in the developing cerebral cortex.

    Science.gov (United States)

    Zhang, Wei; Thevapriya, Selvaratnam; Kim, Paul J; Yu, Wei-Ping; Je, H Shawn; Tan, Eng King; Zeng, Li

    2014-01-01

    Amyloid precursor protein (APP) is a transmembrane glycoprotein proteolytically processed to release amyloid beta, a pathological hallmark of Alzheimer's disease. APP is expressed throughout the developing and mature brain; however, the primary function of this protein is unknown. We previously demonstrated that APP deficiency enhances neurogenesis, but the mechanisms underlying this process are not known. Here we show that APP regulates the expression of microRNAs in the cortex and in neural progenitors, specifically repressing miR-574-5p. We also show that overexpression of miR-574-5p promotes neurogenesis, but reduces the neural progenitor pool. In contrast, the reduced expression of miR-574-5p inhibits neurogenesis and stimulates proliferation in vitro and in utero. We further demonstrate that the inhibition of miR-574-5p in APP-knockout mice rescues the phenotypes associated with APP deficiency in neurogenesis. Taken together, these results reveal a mechanism in which APP regulates the neurogenesis through miRNA-mediated post-transcriptional regulation. PMID:24584353

  9. Overproduction, purification, crystallization and preliminary X-ray analysis of human Fe65-PTB2 in complex with the amyloid precursor protein intracellular domain

    International Nuclear Information System (INIS)

    Alzheimer’s disease is characterized by proteolytic processing of the amyloid precursor protein (APP), which releases the aggregation-prone amyloid-? (A?) peptide and liberates the intracellular domain (AICD) that interacts with various adaptor proteins. The crystallized AICD–Fe65-PTB2 complex is of central importance for APP translocation, nuclear signalling, processing and A? generation. Alzheimer’s disease is associated with typical brain deposits (senile plaques) that mainly contain the neurotoxic amyloid ? peptide. This peptide results from proteolytic processing of the type I transmembrane protein amyloid precursor protein (APP). During this proteolytic pathway the APP intracellular domain (AICD) is released into the cytosol, where it associates with various adaptor proteins. The interaction of the AICD with the C-terminal phosphotyrosine-binding domain of Fe65 (Fe65-PTB2) regulates APP translocation, signalling and processing. Human AICD and Fe65-PTB2 have been cloned, overproduced and purified in large amounts in Escherichia coli. A complex of Fe65-PTB2 with the C-terminal 32 amino acids of the AICD gave well diffracting hexagonal crystals and data have been collected to 2.1 Å resolution. Initial phases obtained by the molecular-replacement method are of good quality and revealed well defined electron density for the substrate peptide

  10. Smoking and serum proteins in atomic-bomb survivors in Japan

    International Nuclear Information System (INIS)

    Associations of smoking habit with serum levels of total protein as well as protein fractions were studied in a population consisting of 4,739 atomic-bomb survivors and unexposed control subjects in Hiroshima, Japan who participated in the 1979-1981 period of the Adult Health Study, an ongoing health follow-up program of the Radiation Effects Research Foundation. Smoking was strongly related to serum protein concentration after correction for age, sex, and body mass index. Among current smokers, levels of total protein, beta globulin, and gamma globulin were significantly lower and levels of alpha-1 and alpha-2 globulin were significantly higher, when compared with nonsmokers. For serum albumin levels a decrease was also noted, but it failed to attain statistical significance. Ex-smokers were indistinguishable from nonsmokers in terms of the serum protein levels analyzed. With an increase of the amount of daily cigarette consumption, monotonic increases of serum levels were observed only in alpha-1 globulin. Duration of smoking was related to increased alpha-1 and alpha-2 globulin. Smoking duration was also associated with albumin level, but the trend was not monotonic. The radiation exposure effect on serum protein level was significant in several instances but was in general much smaller than the smoking effect, and its inclusion in the regression models did not noticeably affect the association between smoking and serum proteins

  11. Serum acute phase proteins in control and Theileria annulata infected water buffaloes (Bubalus bubalis).

    Science.gov (United States)

    El-Deeb, Wael M; Iacob, Olimpia C

    2012-11-23

    This study was carried out to ascertain the changes in acute phase proteins (APPs) and pro-inflammatory cytokines in Theileria annulata infected water buffalo. Thirty infected water buffaloes and 20 parasitologically free were used. In the present study there was significant (P ? 0.05) increase in haptoglobin (Hp), serum amyloid A (SAA), ceruloplasmin, ?1-acid glycoprotein (AGP) and fibrinogen levels (2.18 ± 0.29 g/l, 156.58 ± 3.48 mg/l, 31.23 ± 1.25mg/dl, 370.23 ± 33.21 mg/l and 16.17 ± 1.18 g/l, respectively) in T. annulata infected water buffaloes when compared to healthy ones (0.13 ± 0.01 g/l, 23.9 ± 0.56 mg/l, 21.23 ± 1.21 mg/dl, 240.53 ± 22.45 mg/l and 4.2 ± 0.1 6g/l, respectively). Moreover, there was significant (P ? 0.05) increase in the levels of TNF-?, IL-1?, IL-6, IL-12, IL-1? and IFN-? (2.55 ± 0.12 ng/ml, 98.32 ± 4.21 pg/ml, 152.32 ± 5.62 pg/ml, 26.44 ± 1.43 ng/ml, 240.33 ± 20.45 pg/ml and 123.65 ± 5.67 pg/ml, respectively) in T. annulata infected water buffaloes when compared to healthy ones (0.42 ± 0.04 ng/ml, 55.32 ± 3.21 pg/ml, 88.23 ± 3.21 pg/ml, 7.45 ± 0.67 ng/ml, 98.33 ± 3.45 pg/ml and 34.76 ± 1.56 pg/ml, respectively). There was also significant decrease (P ? 0.05) in the Hb content, PCV%, RBCs and WBCs counts in the diseased water buffaloes compared to the control ones. Neutropenia, eosinopenia, lymphopenia, monocytopenia and thrombocytopenia were also recorded. The biochemical changes revealed significant (P ? 0.05) elevation in the levels of AST, ALT, ALP, LDL-c, VLDL-c, BHBA and NEFA, with significant (P ? 0.05) decrease in the levels of total proteins, albumin, globulins, cholesterol, triglyceride, glucose, G6PD, calcium and phosphorus in T. annulata infected water buffaloes when compared to healthy ones. It could be concluded that APPs and pro-inflammatory cytokines could be used as a valuable biomarkers in T. annulata infected water buffaloes (Bubalus bubalis). PMID:22785130

  12. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis.

    Science.gov (United States)

    Lee, Jae Eun; Lee, Jae Young; Kim, Hong Rye; Shin, Hyun Young; Lin, Tao; Jin, Dong Il

    2015-06-01

    Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum. PMID:25925056

  13. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    Science.gov (United States)

    Lee, Jae Eun; Lee, Jae Young; Kim, Hong Rye; Shin, Hyun Young; Lin, Tao; Jin, Dong Il

    2015-01-01

    Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum. PMID:25925056

  14. Competitive Protein Adsorption of Albumin and Immunoglobulin G from Human Serum onto Polymer Surfaces

    DEFF Research Database (Denmark)

    Holmberg, Maria; Hou, Xiaolin

    2010-01-01

    Competitive protein adsorption from human serum onto unmodified polyethylene terephthalate (PET) surfaces and plasma-polymerized PET surfaces, using the monomer diethylene glycol vinyl ether (DEGVE), has been investigated using radioactive labeling. Albumin and immunoglobulin G (IgG) labeled with two different iodine isotopes have been added to human serum solutions of different concentrations, and adsorption has been performed using adsorption times from approximately 5 s to 24 h. DEGVE surfaces showed indications of being nonfouling regarding albumin and IgG adsorption during competitive protein adsorption from diluted human serum solutions with relatively low protein concentrations, but the nonfouling character was weakened when less diluted human serum solutions with higher protein concentrations were used. The observed adsorption trend is independent of adsorption time, indicating that the protein concentration has a stronger influence on observed adsorption characteristics of the material than the adsorption time has.

  15. Hierarchical Organization in the Amyloid Core of Yeast Prion Protein Ure2*

    OpenAIRE

    Ngo, Sam; Gu, Lei; Guo, Zhefeng

    2011-01-01

    Formation of amyloid fibrils is involved in a range of fatal human disorders including Alzheimer, Parkinson, and prion diseases. Yeast prions, despite differences in sequence from their mammalian counterparts, share similar features with mammalian prions including infectivity, prion strain phenomenon, and species barrier and thus are good model systems for human prion diseases. Yeast prions normally have long prion domains that presumably form multiple ? strands in the fibril, and structural ...

  16. Purification of Hyaluronan Binding Proteins from Human Normal and Cancer Serum

    Directory of Open Access Journals (Sweden)

    Fekry B

    2010-04-01

    Full Text Available Background: Analysis of human cancer serum has revealed the presence of high amounts of hyaluronan (hyaluronic acid, HA when compared to human normal serum, It is well documented that HA and its receptors, known as hyaladherins (HABPs are involved in matrix regulation, cell proliferation, migration and malignant tumour progression. These hyaladherins not only interact with hyaluronan at the matrix proper but also with hyaluronan at the plasma membrane as a cell surface receptors and thus influence cell physiology including secretion of this protein into the circulatory system. Methods: Normal serum and colon cancer serum samples were included in this study, using biochemical techniques such as gel permeation, strong anion exchange chromatography, single dimension electrophoresis and western blot analysis. Results: This study is based on the clinical work of normal serum and colon cancer serum. The description of the procedure was given for the fractionation of serum proteins mainly HABPs from 20 normal and 15 colon cancer patients by using special biotinylated hyaluronan probe. Conclusion: To evaluate whether serum HABPs levels could be used as diagnostic marker for human cancer. The semi purified serum from normal and colon cancer patients showed mainly a major protein (57kDa and a minor one (30kDa by overlay experiments with b-HA probe and these results were confirmed by competition experiments with cold HA.

  17. Y682 mutation of amyloid precursor protein promotes endo-lysosomal dysfunction by disrupting APP-SorLA interaction

    Directory of Open Access Journals (Sweden)

    Luca Rosario La Rosa

    2015-04-01

    Full Text Available The intracellular transport and localization of amyloid precursor protein (APP are critical determinants of APP processing and ?-amyloid peptide production, thus crucially important for the pathophysiology of Alzheimer’s disease (AD. Notably, the C-terminal Y682ENPTY687 domain of APP binds to specific adaptors controlling APP trafficking and sorting in neurons. Mutation on the Y682 residue to glycine (Y682G leads to altered APP sorting in hippocampal neurons that favors its accumulation in intracellular compartments and the release of soluble APP?. Such alterations induce premature aging and learning and cognitive deficits in APP Y682G mutant mice (APPYG/YG. Here, we report that Y682G mutation affects formation of the APP complex with sortilin-related receptor (SorLA, resulting in endo-lysosomal dysfunctions and neuronal degeneration. Moreover, disruption of the APP/SorLA complex changes the trafficking pathway of SorLA, with its consequent increase in secretion outside neurons. Mutations in the SorLA gene are a prognostic factor in AD, and increases in SorLA levels in cerebrospinal fluid are predictive of AD in humans. These results might open new possibilities in comprehending the role played by SorLA in its interaction with APP and in the progression of neuronal degeneration. In addition, they further underline the crucial role played by Y682 residue in controlling APP trafficking in neurons.

  18. Treatment with simvastatin in patients with Alzheimer's disease lowers both alpha- and beta-cleaved amyloid precursor protein.

    DEFF Research Database (Denmark)

    Sjögren, Magnus; Wallin, Anders

    2003-01-01

    We investigated the clinical and biological effects of cholesterol-lowering treatment with a statin in 19 patients with Alzheimer's disease. They received simvastatin 20 mg/day for 12 weeks in an open trial. Primary efficacy parameters were the changes after 12 weeks in the cerebrospinal fluid (CSF) levels of beta-amyloid(42) (Abeta(42)), alpha-secretase-cleaved amyloid precursor protein (alpha-sAPP), beta-secretase-cleaved APP (beta-sAPP), tau, phospho-tau and the plasma levels of Abeta(42). A secondary efficacy parameter was the change in the Alzheimer's Disease Assessment Scale-Cognition (ADAS-cog) score. After 12 weeks, CSF alpha-sAPP and CSF beta-sAPP were significantly reduced (p <0.001), but the CSF levels of tau, phospho-tau, Abeta(42) and the plasma levels of Abeta(42) were unchanged. The ADAS-cog score was slightly increased (p <0.05). The results suggest that simvastatin acts directly on the processing of APP by inhibiting both the alpha- and the beta-secretase pathways.

  19. Treatment with simvastatin in patients with Alzheimer's disease lowers both alpha- and beta-cleaved amyloid precursor protein

    DEFF Research Database (Denmark)

    Sjögren, Magnus; Wallin, Anders

    2003-01-01

    We investigated the clinical and biological effects of cholesterol-lowering treatment with a statin in 19 patients with Alzheimer's disease. They received simvastatin 20 mg/day for 12 weeks in an open trial. Primary efficacy parameters were the changes after 12 weeks in the cerebrospinal fluid (CSF) levels of beta-amyloid(42) (Abeta(42)), alpha-secretase-cleaved amyloid precursor protein (alpha-sAPP), beta-secretase-cleaved APP (beta-sAPP), tau, phospho-tau and the plasma levels of Abeta(42). A secondary efficacy parameter was the change in the Alzheimer's Disease Assessment Scale-Cognition (ADAS-cog) score. After 12 weeks, CSF alpha-sAPP and CSF beta-sAPP were significantly reduced (p < 0.001), but the CSF levels of tau, phospho-tau, Abeta(42) and the plasma levels of Abeta(42) were unchanged. The ADAS-cog score was slightly increased (p < 0.05). The results suggest that simvastatin acts directly on the processing of APP by inhibiting both the alpha- and the beta-secretase pathways.

  20. Presence of non-fibrillar amyloid beta protein in skin biopsies of Alzheimer's disease (AD), Down's syndrome and non-AD normal persons

    DEFF Research Database (Denmark)

    Wen, G Y; Wisniewski, H M; Blondal, H; Benedikz, Eirikur; Frey, H; Pirttila, T; Rudelli, R; Kim, K S

    1994-01-01

    A total of 66 skin biopsies from persons with Alzheimer's disease (AD) or Down's syndrome (DS) and from persons without AD were used in this study. The age range was from 7 to 89 years. Positive immunoreactivity of skin biopsies to monoclonal antibody 4G8, which is reactive to amino acid residue 17-24 of synthetic amyloid beta protein (A beta), and 4G8-Fab (the antigen-binding fragment of 4G8 IgG, reactive only to amyloid plaque) was observed in the epidermis-dermis junction or the basement memb...

  1. Iron and the translation of the amyloid precursor protein (APP) and ferritin: riboregulation against neural oxidative damage in Alzheimer’s disease

    OpenAIRE

    Rogers, Jack; Bush, Ashley; Cho, Hyun-Hee; Smith, Deborah; Thomson, Andrew; Friedlich, Avi; Lahiri, Debomoy K.; Leedman, Peter; Huang, Xudong; Cahill, Catherine C.

    2008-01-01

    The essential metals iron, zinc and copper deposit near the A? (amyloid ?-peptide) plaques in the brain cortex of AD (Alzheimer’s disease) patients. Plaque-associated iron and zinc are in neurotoxic excess at 1 mM concentrations. APP (amyloid precursor protein) is a single transmembrane metalloprotein cleaved to generate the 40-42-amino-acid A?s, which exhibit metal-catalysed neurotoxicity. In health, ubiquitous APP is cleaved in a non-amyloidogenic pathway within its A? domain to release the...

  2. Rhodococcus equi pneumonia in foals: an assessment of the early diagnostic value of serum amyloid A and plasma fibrinogen concentrations in equine clinical practice.

    Science.gov (United States)

    Passamonti, F; Vardi, D M; Stefanetti, V; Marenzoni, M L; Prato, S; Cévese, P; Coletti, M; Pepe, M; Casagrande Proietti, P; Olea-Popelka, F

    2015-02-01

    Early diagnosis and prevention of Rhodococcus equi pneumonia in foals represent important goals for equine clinicians. Recent protocols for diagnosis and treatment of Rhodococcosis in foals typically rely on a multimodal approach based on sonographic evidence suggestive of pyogranulomas, sonographic abscess scores and laboratory findings including plasma fibrinogen concentrations, blood biochemistry testing and platelet and leukocyte counts. The aim of this study was to assess the utility of weekly testing of serum amyloid A (SAA) and plasma fibrinogen concentrations in foals to achieve early diagnosis of R.?equi pneumonia prior to the onset of clinical signs. This testing was used to simulate a clinically practical screening procedure and compared with thoracic ultrasonography performed in parallel. The present study suggests that SAA does not represent a reliable early marker of Rhodococcosis when plasma concentrations are tested weekly. However, when clinical signs of R.?equi pneumonia are present, SAA concentrations may allow clinicians to obtain 'real-time' indications concerning both the progress of infection and the effectiveness of therapy. This study raises the possibility that plasma fibrinogen monitoring starting at 1 week of age and repeated on a weekly basis, could serve as a screening test allowing clinicians to identify foals as suspected of R.?equi infection. Future investigations regarding both physiological plasma fibrinogen concentrations in foals as well as fibrinogen kinetics in foals affected with R.?equi pneumonia, including the establishment of appropriate reference intervals for the test method employed in this study, will be necessary in order to clarify this possibility. PMID:25555337

  3. First Identification of Resident and Circulating Fibrocytes in Dupuytren’s Disease Shown to Be Inhibited by Serum Amyloid P and Xiapex

    Science.gov (United States)

    Iqbal, Syed Amir; Hayton, Michael John; Watson, James Stewart; Szczypa, Piotr; Bayat, Ardeshir

    2014-01-01

    Dupuytren’s disease (DD) is a common progressive fibroproliferative disorder causing permanent digital contracture. Proliferative myofibroblasts are thought to be the cells responsible for DD initiation and recurrence, although their source remains unknown. DD tissue has also been shown to harbor mesenchymal and hematopoietic stem cells. Fibrocytes are circulating cells that show characteristics of fibroblasts and they express surface markers for both hematopoietic and mesenchymal stromal cells. Fibrocytes differentiate from peripheral CD14+ mononuclear cells, which can be inhibited by serum amyloid P (SAP). In this study we have demonstrated the presence of fibrocytes in DD blood and tissue, moreover we have evaluated the effects of SAP and Xiapex (Collagenase Clostridium histolyticum) on fibrocytes derived from DD. H&E staining showed typical Spindle shaped morphology of fibrocytes. FACS analysis based on a unique combination of 3 markers, revealed the increased presence of fibrocytes in blood and tissue of DD patients. Additionally, immunohistology of DD nodule and cord tissue showed the presence of collagen 1+/CD34+ cells. No difference in plasma SAP levels was observed between DD and control. Higher concentrations of SAP significantly inhibited fibrocytes differentiated from DD derived monocytes compared to control. DD fascia derived fibrocytes showed resistance to growth inhibition by SAP, particularly nodule derived fibrocytes showed robust growth even at higher SAP concentrations compared to control. DD derived fibrocytes were positive for typical fibrocyte dual markers, i.e. Collagen 1/LSP-1 and collagen 1/CD34. Xiapex was more effective in inhibiting the growth of nodule derived cells compared to commercially available collagenase A. Our results show for the first time the increased presence of fibrocytes in DD patient’s blood and disease tissue compared to control tissue. Additionally, we evaluate the response of these fibrocytes to SAP and Xiapex therapy. PMID:24933153

  4. A role for the high-density lipoprotein receptor SR-B1 in synovial inflammation via serum amyloid-A.

    LENUS (Irish Health Repository)

    Mullan, Ronan Hugh

    2012-02-01

    Acute phase apoprotein Serum Amyloid A (A-SAA), which is strongly expressed in rheumatoid arthritis synovial membrane (RA SM), induces angiogenesis, adhesion molecule expression, and matrix metalloproteinase production through the G-coupled receptor FPRL-1. Here we report alternative signaling through the high-density lipoprotein receptor scavenger receptor-class B type 1 (SR-B1). Quantitative expression\\/localization of SR-B1 in RA SM, RA fibroblast-like cells (FLCs), and microvascular endothelial cells (ECs) was assessed by Western blotting and immunohistology\\/fluorescence. A-SAA-mediated effects were examined using a specific antibody against SR-B1 or amphipathic alpha-Helical Peptides (the SR-B1 antagonists L-37pA and D-37pA), in RA FLCs and ECs. Adhesion molecule expression and cytokine production were quantified using flow cytometry and ELISA. SR-B1 was strongly expressed in the RA SM lining layer and endothelial\\/perivascular regions compared with osteoarthritis SM or normal control synovium. Differential SR-B1 expression in RA FLC lines (n = 5) and ECs correlated closely with A-SAA, but not tumor necrosis factor alpha-induced intercellular adhesion molecule-1 upregulation. A-SAA-induced interleukin-6 and -8 production was inhibited in the presence of anti-SR-B1 in human microvascular endothelial cells and RA FLCs. Moreover, D-37pA and L-37pA inhibited A-SAA-induced vascular cell adhesion molecule-1 and intercellular adhesion molecule expression from ECs in a dose-dependent manner. As SR-B1 is expressed in RA synovial tissue and mediates A-SAA-induced pro-inflammatory pathways, a better understanding of A-SAA-mediated inflammatory pathways may lead to novel treatment strategies for RA.

  5. Amyloid tumour of the rectum.

    OpenAIRE

    Senapati, A.; Fletcher, C; Bultitude, M I; Jackson, B T

    1995-01-01

    Systemic amyloidosis results in diffuse deposition of amyloid proteins in various organs. Localized deposits in the form of nodules also occur but are rare in the gastrointestinal tract. A localized amyloid deposit in the rectum that was clinically indistinguishable from carcinoma of the rectum or prostate is described.

  6. Aggregation properties of a short peptide that mediates amyloid fibril formation in model proteins unrelated to disease

    Indian Academy of Sciences (India)

    Nitin Chaudhary; Shashi Singh; Ramakrishnan Nagaraj

    2011-09-01

    Short peptides have been identified from amyloidogenic proteins that form amyloid fibrils in isolation. The hexapeptide stretch 21DIDLHL26 has been shown to be important in the self-assembly of the Src homology 3 (SH3) domain of p85 subunit of bovine phosphatidylinositol-3-kinase (PI3-SH3). The SH3 domain of chicken brain -spectrin, which is otherwise non-amyloidogenic, is rendered amyloidogenic if 22EVTMKK27 is replaced by DIDLHL. In this article, we describe the aggregation behaviour of DIDLHL-COOH and DIDLHL-CONH2. Our results indicate that DIDLHL-COOH and DIDLHL-CONH2 aggregate to form spherical structures at pH 5 and 6. At pH 5, in the presence of mica, DIDLHL-CONH2 forms short fibrous structures. The presence of NaCl along with mica results in fibrillar structures. At pH 6, DIDLHL-CONH2 forms largely spherical aggregates. Both the peptides are unstructured in solution but adopt -conformation on drying. The aggregates formed by DIDLHL-COOH and DIDLHL-CONH2 are formed during drying process and their structures are modulated by the presence of mica and salt. Our study suggests that a peptide need not have intrinsic amyloidogenic propensity to facilitate the selfassembly of the full-length protein. The propensity of peptides to form self-assembled structures that are non-amyloidogenic could be important in potentiating the self-assembly of full-length proteins into amyloid fibrils.

  7. Mechanism of Inhibition of beta-site amyloid precursor protein-cleaving enzyme (BACE) by a statine-based peptide.

    Science.gov (United States)

    Marcinkeviciene, J; Luo, Y; Graciani, N R; Combs, A P; Copeland, R A

    2001-06-29

    Inhibition of beta-site amyloid precursor protein-cleaving enzyme by a statine-based inhibitor has been studied using steady state and stopped-flow methods. A slow onset rate of inhibition has been observed under steady state conditions, and a K(i) of 22 nm has been derived using progress curves analysis. Simulation of stopped-flow protein fluorescence transients provided an estimate of the K(d) for initial inhibitor binding of 660 nm. A two-step inhibition mechanism is proposed, wherein slower "tightening up" of the initial encounter complex occurs. Two hypotheses have been proposed in the literature to address the nature of the slow step in the inhibition of aspartic proteases by peptidomimetic inhibitors: a conformational change related to the "flap" movement and displacement of a catalytic water. We compared substrate and inhibitor binding rates under pre-steady-state conditions. Both ligands are likely to cause flap movement, whereas no catalytic water replacement occurs during substrate binding. Our results suggest that both ligands bind to the enzyme at a rate significantly lower than the diffusion limit, but there are additional rate limitations involved in inhibitor binding, resulting in a k(on) of 3.5 x 10(4) m(-)1 s(-)1 for the inhibitor compared with 3.5 x 10(5) m(-)1 s(-)1 for the substrate. Even though specific intermediate formation steps might be different in the productive inhibitor and substrate binding to beta-site amyloid precursor protein-cleaving enzyme, a similar final optimized conformation is achieved in both cases, as judged by the comparable free energy changes (DeltaDeltaG of 2.01 versus 1.97 kcal/mol) going from the initial to the final enzyme-inhibitor or enzyme-substrate complexes. PMID:11306583

  8. Amyloid Fibril Solubility

    CERN Document Server

    Rizzi, L G

    2015-01-01

    It is well established that amyloid fibril solubility is protein specific, but how solubility depends on the interactions between the fibril building blocks is not clear. Here we use a simple protein model and perform Monte Carlo simulations to directly measure the solubility of amyloid fibrils as a function of the interaction between the fibril building blocks. Our simulations confirms that the fibril solubility depends on the fibril thickness and that the relationship between the interactions and the solubility can be described by a simple analytical formula. The results presented in this study reveal general rules how side-chain side-chain interactions, backbone hydrogen bonding and temperature affect amyloid fibril solubility, which might prove a powerful tool to design protein fibrils with desired solubility and aggregation properties in general.

  9. Effect of water salinity on total protein and electrophoretic pattern of serum proteins of grass carp, Ctenopharyngodon idella.

    Science.gov (United States)

    Peyghan, Rahim; Khadjeh, Gholam Hosain; Enayati, Ala

    2014-01-01

    In this study the effects of water salinity on serum total protein and its components in grass carp were investigated. The aim of this study was to determine the effect of salinity tolerance of fish on total serum protein level and its components as an indicator of liver and kidney activity. One hundred and twenty grass carp were divided into four groups, randomly. The first three groups were reared in concentration of 4, 8 and 12 g L(-1) of salt solution, respectively, and the fourth group was reared in freshwater and served as control. After 3 weeks, blood samples were collected and after harvesting the blood serum, serum total protein and protein components were measured with Biuret and electrophoresis methods, respectively. Results showed that mean value of serum total protein in the control and three salinities groups were 2.75, 3.28, 2.90 and 3.13 g dL(-1), respectively. Five fractions of serum protein were electrophoretically observed as: albumin (Alb), alpha-1 globulin (?1-glu), alpha-2 globulin (?2-glu), beta globulin (?-glu) and gamma globulin (?-glu). There were not any significant differences between the average mean of serum total protein of experimental and control groups (p > 0.05). However, Alb, ?1-glu and ?-glu levels in the experimental groups were significantly higher than in the control group (p 0.05). In conclusion, our results showed that increasing water salinity could have a significant effect on Alb, ?1-glu and ?-glu levels but not on total serum protein in grass carp. PMID:25568723

  10. PrionW: a server to identify proteins containing glutamine/asparagine rich prion-like domains and their amyloid cores.

    Science.gov (United States)

    Zambrano, Rafael; Conchillo-Sole, Oscar; Iglesias, Valentin; Illa, Ricard; Rousseau, Frederic; Schymkowitz, Joost; Sabate, Raimon; Daura, Xavier; Ventura, Salvador

    2015-07-01

    Prions are a particular type of amyloids with the ability to self-perpetuate and propagate in vivo. Prion-like conversion underlies important biological processes but is also connected to human disease. Yeast prions are the best understood transmissible amyloids. In these proteins, prion formation from an initially soluble state involves a structural conversion, driven, in many cases, by specific domains enriched in glutamine/asparagine (Q/N) residues. Importantly, domains sharing this compositional bias are also present in the proteomes of higher organisms, thus suggesting that prion-like conversion might be an evolutionary conserved mechanism. We have recently shown that the identification and evaluation of the potency of amyloid nucleating sequences in putative prion domains allows discrimination of genuine prions. PrionW is a web application that exploits this principle to scan sequences in order to identify proteins containing Q/N enriched prion-like domains (PrLDs) in large datasets. When used to scan the complete yeast proteome, PrionW identifies previously experimentally validated prions with high accuracy. Users can analyze up to 10 000 sequences at a time, PrLD-containing proteins are identified and their putative PrLDs and amyloid nucleating cores visualized and scored. The output files can be downloaded for further analysis. PrionW server can be accessed at http://bioinf.uab.cat/prionw/. PMID:25977297

  11. Serum protein profiling by solid phase extraction and mass spectrometry: A future diagnostics tool?

    DEFF Research Database (Denmark)

    Callesen, Anne K; Madsen, Jonna S; Vach, Werner; Kruse, Torben A; Mogensen, Ole; Jensen, Ole Nørregaard

    2009-01-01

    Serum protein profiling by MS is a promising method for early detection of disease. Important characteristics for serum protein profiling are preanalytical factors, analytical reproducibility and high throughput. Problems related to preanalytical factors can be overcome by using standardized and rigorous sample collection and sample handling protocols. The sensitivity of the MS analysis relies on the quality of the sample; consequently, the blood sample preparation step is crucial to obtain pure...

  12. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    OpenAIRE

    Lee, Jae Eun; Lee, Jae Young; Kim, Hong Rye; Shin, Hyun Young; Lin, Tao; Jin, Dong Il

    2015-01-01

    Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2...

  13. Discovery and fine mapping of serum protein loci through transethnic meta-analysis.

    OpenAIRE

    Franceschini, N; van Rooij, FJ; Prins, BP; Feitosa, MF; Karakas, M.; Eckfeldt, JH; Folsom, AR; Kopp, J.; Vaez, A; Andrews, JS.; Baumert, J.; Boraska, V; Broer, L; Hayward, C.; Ngwa, JS

    2012-01-01

    Many disorders are associated with altered serum protein concentrations, including malnutrition, cancer, and cardiovascular, kidney, and inflammatory diseases. Although these protein concentrations are highly heritable, relatively little is known about their underlying genetic determinants. Through transethnic meta-analysis of European-ancestry and Japanese genome-wide association studies, we identified six loci at genome-wide significance (p < 5 × 10(-8)) for serum albumin (HPN-SCN1B, GCKR-F...

  14. Genetic factors explain half of all variance in serum eosinophil cationic protein

    DEFF Research Database (Denmark)

    Elmose, Camilla; Sverrild, Asger; van der Sluis, Sophie; Kyvik, K O; Backer, Vibeke; Thomsen, Simon Francis

    2014-01-01

    BACKGROUND: Eosinophil cationic protein (ECP) is one of four basic proteins of the secretory granules of eosinophils. It has a variety of functions associated with inflammatory responses. Little is known about the causes for variation in serum ECP levels. AIM: To identify factors associated with variation in serum ECP and to determine the relative proportion of the variation in ECP due to genetic and non-genetic factors, in an adult twin sample. METHODS: A sample of 575 twins, selected through a...

  15. Role of maternal serum Chlamydia trachomatis IgG antibodies and serum C- reactive protein in preterm labour

    OpenAIRE

    Preeti Dubey; Kiran Pandey; Neetu Singh; Ajay Bhagoliwal; Deepti Sharma

    2014-01-01

    Background: The objective was to find the role of maternal serum C- reactive protein and Chlamydia trachomatis IgG antibodies as predictors of preterm delivery. Methods: This prospective study was conducted in UISEMH, Department of Obstetrics and Gynecology, GSVM Medical College, Kanpur from September 2011 to September 2013. The present study comprised of a total of 100 cases, out of which 50 were in study group and 50 in control group. Cases were compared with respect to presence of Chla...

  16. Testing the Neurovascular Hypothesis of Alzheimer’s Disease: LRP-1 Antisense Reduces Blood-Brain Barrier Clearance, Increases Brain Levels of Amyloid-? Protein, and Impairs Cognition

    OpenAIRE

    Jaeger, Laura B.; Dohgu, Shinya; Hwang, Mark C.; Farr, Susan A.; Murphy, M Paul; Fleegal-DeMotta, Melissa A; Lynch, Jessica L.; Robinson, Sandra M.; Niehoff, Michael L.; Johnson, Steven N.; Kumar, Vijaya B.; Banks, William A

    2009-01-01

    Decreased clearance is the main reason amyloid-? protein (A?) in increased in the brains of patients with Alzheimer’s disease (AD). The neurovascular hypothesis states that this decreased clearance is caused by impairment of low density lipoprotein receptor related protein-1 (LRP-1), the major brain-to-blood transporter of A? at the blood-brain barrier (BBB). As deletion of the LRP-1 gene is a lethal mutation, we tested the neurovascular hypothesis by developing a cocktail of phosphorothioate...

  17. Crystal structure of amyloid precursor-like protein 1 and heparin complex suggests a dual role of heparin in E2 dimerization

    OpenAIRE

    Xue, Yi; Lee, SangWon; Ha, Ya

    2011-01-01

    Mutations in amyloid precursor protein (APP) are associated with familial Alzheimer’s disease. Recent development suggests that homo- and heterodimerization of APP and APP-like proteins (APLPs), which are enhanced by heparan sulfate binding, may play a role in signal transduction and cell adhesion. Despite efforts to model heparin binding based on known apo crystal structures, the mechanism of heparin-induced APP/APLP dimerization has not been established experimentally. Here we report the cr...

  18. Memory-enhancing effects of secreted forms of the beta-amyloid precursor protein in normal and amnestic mice.

    Science.gov (United States)

    Meziane, H; Dodart, J C; Mathis, C; Little, S; Clemens, J; Paul, S M; Ungerer, A

    1998-10-13

    When administered intracerebroventricularly to mice performing various learning tasks involving either short-term or long-term memory, secreted forms of the beta-amyloid precursor protein (APPs751 and APPs695) have potent memory-enhancing effects and block learning deficits induced by scopolamine. The memory-enhancing effects of APPs were observed over a wide range of extremely low doses (0.05-5,000 pg intracerebroventricularly), blocked by anti-APPs antisera, and observed when APPs was administered either after the first training session in a visual discrimination or a lever-press learning task or before the acquisition trial in an object recognition task. APPs had no effect on motor performance or exploratory activity. APPs695 and APPs751 were equally effective in the object recognition task, suggesting that the memory-enhancing effect of APPs does not require the Kunitz protease inhibitor domain. These data suggest an important role for APPss on memory processes. PMID:9770546

  19. The Amyloid Precursor Protein of Alzheimer's Disease in the Reduction of Copper(II) to Copper(I)

    Science.gov (United States)

    Multhaup, Gerd; Schlicksupp, Andrea; Hesse, Lars; Beher, Dirk; Ruppert, Thomas; Masters, Colin L.; Beyreuther, Konrad

    1996-03-01

    The transition metal ion copper(II) has a critical role in chronic neurologic diseases. The amyloid precursor protein (APP) of Alzheimer's disease or a synthetic peptide representing its copper-binding site reduced bound copper(II) to copper(I). This copper ion-mediated redox reaction led to disulfide bond formation in APP, which indicated that free sulfhydryl groups of APP were involved. Neither superoxide nor hydrogen peroxide had an effect on the kinetics of copper(II) reduction. The reduction of copper(II) to copper(I) by APP involves an electron-transfer reaction and could enhance the production of hydroxyl radicals, which could then attack nearby sites. Thus, copper-mediated toxicity may contribute to neurodegeneration in Alzheimer's disease.

  20. 3-Hydroxy-4-pyridinone derivatives designed for fluorescence studies to determine interaction with amyloid protein as well as cell permeability.

    Science.gov (United States)

    Telpoukhovskaia, Maria A; Cawthray, Jacqueline F; Rodríguez-Rodríguez, Cristina; Scott, Lauren E; Page, Brent D G; Patrick, Brian O; Orvig, Chris

    2015-09-01

    Finding a cure for Alzheimer's disease is an urgent goal. Multifunctional metal binders are used to elucidate its pathological features and investigated as potential therapeutics. The use of physicochemical and TD-DFT calculations constituted successful strategy in the design of 1-(4-(benzo[d]oxazol-2-yl)phenyl)-3-hydroxy-2-methylpyridin-4(1H)-one (HL21) and 1-(4-(benzo[d]thiazol-2-yl)phenyl)-3-hydroxy-2-methylpyridin-4(1H)-one (HL22). We report the synthesis and full characterization of these compounds, including X-ray crystallography. Using fluorescent signal as the readout, it was determined that HL22 interacts with amyloid-beta protein fibrils, and permeates into bEnd.3 cells used as a mimic of the blood-brain barrier. This provides the first example of direct investigation of our hydroxypyridinone compounds within a biological setting. PMID:26141772

  1. Elevated serum immunoinflammation-related protein complexes are associated with psychosis.

    Science.gov (United States)

    Liu, Yujie; Zhang, Dan; Cheng, Yuhang; Li, Zhili

    2015-11-30

    Emerging evidence suggests an underlying immune and inflammatory response for a variety of psychiatric disorders. Herein, we employed an optimized native-polyacrylamide gel electrophoresis to isolate psychosis-related serum immunoinflammation-related protein complexes (IIRPCs) from 147 patients with schizophrenia (SCH), 158 patients with bipolar disorder (BPD), 132 patients with other psychosis, and 145 normal controls. All participants could be classified into four categories based on serum IIRPCs, which correspond to 290, 215, 70, and 7 serum samples, correspondingly. For each category, significantly enhanced levels of serum IIRPCs in patients with SCH, BPD, and other psychosis groups were observed compared with normal controls. Receiver operating characteristic analysis indicated that serum IIRPCs have excellent diagnostic performance to differentiate SCH, BPD, and other psychosis groups from normal controls, with high sensitivities and specificities of >85%. Total serum amounts of IgG, IgA, and IgM in all patients were significantly decreased compared with normal controls. PMID:26337482

  2. Sea lamprey (Petromyzon marinus) contain four developmentally regulated serum thyroid hormone distributor proteins.

    Science.gov (United States)

    Gross, Tianna Natalia; Manzon, Richard Giuseppe

    2011-02-01

    Thyroid hormones (THs) are very lipophilic molecules which require a distribution network for efficient transport in serum. Despite observations that THs function in a wide variety of processes, including aspects of fish development (i.e., flat fish metamorphosis and smoltification), the proteins responsible for TH distribution in fish serum remain poorly studied. We chose to investigate the serum TH distributor proteins (THDPs) in lampreys. As one of only two extant agnathans, data on lamprey THDPs may offer new insights into the evolution of the vertebrate TH distribution network and serum proteins in general. Moreover, lampreys appear to contradict the vertebrate model of an increase in TH concentrations initiating and driving vertebrate metamorphosis. We show for the first time that sea lamprey serum contains at least four THDPs and that their presence in serum is temporally regulated throughout the life cycle. The albumin, glycoprotein AS is the dominant THDP present in the sera of larval and metamorphosing sea lamprey. In stage seven of metamorphosis, three additional THDPs appear, including the albumin, glycoprotein SDS-1; the glycolipoprotein CB-III; and an unidentified low molecular weight protein temporarily named Spot-5. The sera of parasitic and upstream migrant sea lampreys lack AS; their serum THDPs are SDS-1, CB-III, and Spot-5. Our data indicate that despite the change in type and number of THDPs, the overall total TH binding capacity of sea lamprey serum remains fairly stable until stage 7 of metamorphosis when a only modest decrease in total binding capacity is observed. Collectively these data indicate that the decline in serum TH concentrations observed during lamprey metamorphosis is not a consequence of a reduction in the distribution and storage capacity of the serum. PMID:21163261

  3. ALTERATIONS IN TOTAL PROTEIN CONCENTRATION, SERUM PROTEIN FRACTIONS AND ALBUMIN/GLOBULIN RATIO IN HEALTHY RABBITS

    Directory of Open Access Journals (Sweden)

    Nuzhat Sultana

    2013-08-01

    Full Text Available This study assessed the effect of oral administration of Aloe vera and was to evaluate total serum protein, albumin and globulin concentrations as well as albumin / globulin (A / G ratio. Twenty rabbits weighing 1000 – 1800 g were divided into 2 groups. Each group consisted of ten animals. One served as control and other group served as experimental group. Results show that animals after 07, 15 and 30 days dosing of Aloe vera showed highly significant decrease in total protein and globulin and highly significant decrease in Albumin after 15 and 30 days of dosing of Aloe vera in comparison to control animals group. It is concluded that the long-term use of Aloe vera may cause hypoglobinemia and hypoalbuminemia at 30 days of dosing and it could be due to the liver diseases, evidence of hepatotoxicity induced Aloe vera also reported in previous studies.

  4. Functional Amyloid Formation within Mammalian Tissue

    OpenAIRE

    Fowler, Douglas M.; Koulov, Atanas V; Alory-Jost, Christelle; Marks, Michael S.; Balch, William E.; Kelly, Jeffery W

    2005-01-01

    Amyloid is a generally insoluble, fibrous cross-? sheet protein aggregate. The process of amyloidogenesis is associated with a variety of neurodegenerative diseases including Alzheimer, Parkinson, and Huntington disease. We report the discovery of an unprecedented functional mammalian amyloid structure generated by the protein Pmel17. This discovery demonstrates that amyloid is a fundamental nonpathological protein fold utilized by organisms from bacteria to humans. We have found that Pmel17 ...

  5. Functional Amyloid Formation within Mammalian Tissue.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available Amyloid is a generally insoluble, fibrous cross-beta sheet protein aggregate. The process of amyloidogenesis is associated with a variety of neurodegenerative diseases including Alzheimer, Parkinson, and Huntington disease. We report the discovery of an unprecedented functional mammalian amyloid structure generated by the protein Pmel17. This discovery demonstrates that amyloid is a fundamental nonpathological protein fold utilized by organisms from bacteria to humans. We have found that Pmel17 amyloid templates and accelerates the covalent polymerization of reactive small molecules into melanin-a critically important biopolymer that protects against a broad range of cytotoxic insults including UV and oxidative damage. Pmel17 amyloid also appears to play a role in mitigating the toxicity associated with melanin formation by sequestering and minimizing diffusion of highly reactive, toxic melanin precursors out of the melanosome. Intracellular Pmel17 amyloidogenesis is carefully orchestrated by the secretory pathway, utilizing membrane sequestration and proteolytic steps to protect the cell from amyloid and amyloidogenic intermediates that can be toxic. While functional and pathological amyloid share similar structural features, critical differences in packaging and kinetics of assembly enable the usage of Pmel17 amyloid for normal function. The discovery of native Pmel17 amyloid in mammals provides key insight into the molecular basis of both melanin formation and amyloid pathology, and demonstrates that native amyloid (amyloidin may be an ancient, evolutionarily conserved protein quaternary structure underpinning diverse pathways contributing to normal cell and tissue physiology.

  6. Using competitive protein adsorption to measure fibrinogen in undiluted human serum

    Science.gov (United States)

    Choi, Seokheun; Wang, Ran; Lajevardi-Khosh, Arad; Chae, Junseok

    2010-12-01

    We report a unique sensing mechanism based on competitive protein adsorption to measure fibrinogen, a cardiovascular biomarker, in undiluted human serum. The method uses physical adsorption of proteins to a surface rather than complex and time-consuming immobilization procedures. Two fibrinogen concentrations were differentiated in spiked in human serum [3.0 mg/ml (normal concentration) versus 3.2 mg/ml (abnormal concentration with heart disease)]. Real-time surface plasmon resonance signals were monitored as fibrinogen displaced a preadsorbed protein, IgM, on a hydrophobic gold surface. The relatively strong-affinity protein, IgM, was displaced primarily by fibrinogen and much less by other proteins in human serum.

  7. Crystallization and preliminary crystallographic studies of the copper-binding domain of the amyloid precursor protein of Alzheimer’s disease

    International Nuclear Information System (INIS)

    The binding of Cu2+ ions to the copper-binding domain of the amyloid precursor protein of Alzheimer’s disease reduces the production of the amyloid ? peptide, which is centrally involved in Alzheimer’s disease. Structural studies of the copper-binding domain will provide a basis for structure-based drug design that might prove useful in treating this devastating disease. Alzheimer’s disease is thought to be triggered by production of the amyloid ? (A?) peptide through proteolytic cleavage of the amyloid precursor protein (APP). The binding of Cu2+ to the copper-binding domain (CuBD) of APP reduces the production of A? in cell-culture and animal studies. It is expected that structural studies of the CuBD will lead to a better understanding of how copper binding causes A? depletion and will define a potential drug target. The crystallization of CuBD in two different forms suitable for structure determination is reported here

  8. Antibody binding to cell surface amyloid precursor protein induces neuronal injury by deregulating the phosphorylation of focal adhesion signaling related proteins.

    Science.gov (United States)

    Xu, Yu-Xia; Wang, Hong-Quan; Yan, Jie; Sun, Xiao-Bo; Guo, Jing-Chun; Zhu, Cui-Qing

    2009-11-20

    The biological function of full-length amyloid-beta protein precursor (APP), the precursor of Abeta, is not fully understood. Mounting studies reported that antibody binding to cell surface APP causes neuronal injury. However, the mechanism of cell surface APP mediating neuronal injury remains to be determined. Colocalization of APP with integrin on cell surface leads us to suppose that focal adhesion (FA) related mechanism is involved in surface APP-mediated neuronal injury. In the present study, results demonstrated that primary cultured neurons treated with antibody against APP-N-terminal not only caused neuronal injury and aberrant morphologic changes of neurite, but also induced reaction of FA proteins appearing an acute increase then decrease pattern. Moreover, the elevation of tyrosine phosphorylation of FA proteins including paxillin and focal adhesion kinase (FAK), and down-regulated expression of protein tyrosine phosphatase (PTP1B) induced by APP antibody were prevented by inhibitor of Src protein kinases 4-amino-5-(4-chlorophenyl)-7(t-butyl) pyrazol (3,4-D) pyramide (PP2) and G protein inhibitor pertussis toxin (PTX), implying that Src family kinase and G protein play roles in APP-induced FA signals. In addition, pretreatment with PTX and PP2 was able to suppress APP-antibody induced neuronal injury. Taken together, the results suggest a novel mechanism for APP mediating neuronal injury through deregulating FA signals. PMID:19766167

  9. Effect of Spray Drying on Protein Content of Natural Rubber Serum (NRS

    Directory of Open Access Journals (Sweden)

    I. Aimi Izyana and M.N. Zairossani

    2011-12-01

    Full Text Available Natural rubber latex comprises approximately 70% natural rubber serum (NRS which is the aqueous part of the latex. The NRS is made up of mainly water and non-rubber components; sugar, protein and other lipids. The protein component of the NRS is separated using membrane separation and spray dried whereby the amino acid and protein content was monitored during the process. The optimum drying temperatures were first determined to obtain the maximum recovery of the protein powder, whereby the amino acid content was approximately 40 times that of the feed. The production of protein powder from NRS increases the rubber industry's competitiveness through value addition to the previously discarded NRS but also to the processing industry. NRS protein powder has a great opportunity to be developed as an alternative protein source.ABSTRAK: Susu getah asli mengandungi lebih kurang 70% serum getah asli (natural rubber serum (NRS iaitu bahagian susu getah yang berair. NRS sebahagian besarnya merupakan air dan komponen bukan getah; gula, protein dan lipid-lipid lain. Komponen protein NRS dipisahkan dengan menggunakan membran pemisah dan kaedah kering semburan dimana asid amino dan kandungan protein dipantau semasa proses tersebut. Pada mulanya, suhu pengeringan optimum ditentukan untuk mendapatkan hasil maksima serbuk protein, dimana kandungan asid amino adalah lebih kurang 40 kali suapan. Penghasilan serbuk protein daripada NRS meningkatkan daya saing industri getah dan industri pemprosesan menerusi pertambahan nilai terhadap NRS yang sebelum ini hanya dibuang. Serbuk protein NRS mempunyai peluang besar untuk dimajukan sebagai sumber protein alternatif.KEY WORDS:  protein, spray dry, natural rubber serum.

  10. Transcriptional regulation of human FE65, a ligand of Alzheimer's disease amyloid precursor protein, by Sp1.

    LENUS (Irish Health Repository)

    Yu, Hoi-Tin

    2010-03-01

    FE65 is a neuronal-enriched adaptor protein that binds to the Alzheimer\\'s disease amyloid precursor protein (APP). FE65 forms a transcriptionally active complex with the APP intracellular domain (AICD). The precise gene targets for this complex are unclear but several Alzheimer\\'s disease-linked genes have been proposed. Additionally, evidence suggests that FE65 influences APP metabolism. The mechanism by which FE65 expression is regulated is as yet unknown. To gain insight into the regulatory mechanism, we cloned a 1.6 kb fragment upstream of the human FE65 gene and found that it possesses particularly strong promoter activity in neurones. To delineate essential regions in the human FE65 promoter, a series of deletion mutants were generated. The minimal FE65 promoter was located between -100 and +5, which contains a functional Sp1 site. Overexpression of the transcription factor Sp1 potentiates the FE65 promoter activity. Conversely, suppression of the FE65 promoter was observed in cells either treated with an Sp1 inhibitor or in which Sp1 was knocked down. Furthermore, reduced levels of Sp1 resulted in downregulation of endogenous FE65 mRNA and protein. These findings reveal that Sp1 plays a crucial role in transcriptional control of the human FE65 gene.

  11. Monoacylated Cellular Prion Proteins Reduce Amyloid-?-Induced Activation of Cytoplasmic Phospholipase A2 and Synapse Damage.

    Science.gov (United States)

    West, Ewan; Osborne, Craig; Nolan, William; Bate, Clive

    2015-01-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid-? (A?) and the loss of synapses. Aggregation of the cellular prion protein (PrPC) by A? oligomers induced synapse damage in cultured neurons. PrPC is attached to membranes via a glycosylphosphatidylinositol (GPI) anchor, the composition of which affects protein targeting and cell signaling. Monoacylated PrPC incorporated into neurons bound "natural A?", sequestering A? outside lipid rafts and preventing its accumulation at synapses. The presence of monoacylated PrPC reduced the A?-induced activation of cytoplasmic phospholipase A2 (cPLA2) and A?-induced synapse damage. This protective effect was stimulus specific, as treated neurons remained sensitive to ?-synuclein, a protein associated with synapse damage in Parkinson's disease. In synaptosomes, the aggregation of PrPC by A? oligomers triggered the formation of a signaling complex containing the cPLA2.a process, disrupted by monoacylated PrPC. We propose that monoacylated PrPC acts as a molecular sponge, binding A? oligomers at the neuronal perikarya without activating cPLA2 or triggering synapse damage. PMID:26043272

  12. Monoacylated Cellular Prion Proteins Reduce Amyloid-?-Induced Activation of Cytoplasmic Phospholipase A2 and Synapse Damage

    Directory of Open Access Journals (Sweden)

    Ewan West

    2015-06-01

    Full Text Available Alzheimer’s disease (AD is a progressive neurodegenerative disease characterized by the accumulation of amyloid-? (A? and the loss of synapses. Aggregation of the cellular prion protein (PrPC by A? oligomers induced synapse damage in cultured neurons. PrPC is attached to membranes via a glycosylphosphatidylinositol (GPI anchor, the composition of which affects protein targeting and cell signaling. Monoacylated PrPC incorporated into neurons bound “natural A?”, sequestering A? outside lipid rafts and preventing its accumulation at synapses. The presence of monoacylated PrPC reduced the A?-induced activation of cytoplasmic phospholipase A2 (cPLA2 and A?-induced synapse damage. This protective effect was stimulus specific, as treated neurons remained sensitive to ?-synuclein, a protein associated with synapse damage in Parkinson’s disease. In synaptosomes, the aggregation of PrPC by A? oligomers triggered the formation of a signaling complex containing the cPLA2.a process, disrupted by monoacylated PrPC. We propose that monoacylated PrPC acts as a molecular sponge, binding A? oligomers at the neuronal perikarya without activating cPLA2 or triggering synapse damage.

  13. Probing folding free energy landscape of small proteins through minimalistic models: Folding of HP-36 and -amyloid

    Indian Academy of Sciences (India)

    Arnab Mukherjee; Biman Bagchi

    2003-10-01

    Folding dynamics and energy landscape picture of protein conformations of HP-36 and -amyloid (A) are investigated by extensive Brownian dynamics simulations, where the inter amino acid interactions are given by a minimalistic model (MM) we recently introduced [J. Chem. Phys. 118 4733 (2003)]. In this model, a protein is constructed by taking two atoms for each amino acid. One atom represents the backbone C$_{\\alpha}$ atom, while the other mimics the whole side chain residue. Sizes and interactions of the side residues are all different and specific to a particular amino acid. The effect of water-mediated folding is mapped into the MM by suitable choice of interaction parameters of the side residues obtained from the amino acid hydropathy scale. A new non-local helix potential is incorporated to generate helices at the appropriate positions in a protein. Simulations have been done by equilibrating the protein at high temperature followed by a sudden quench. The subsequent folding is monitored to observe the dynamics of topological contacts ($N_{topo}$), relative contact order parameter (RCO), and the root mean square deviation (RMSD) from the realprotein native structure. The folded structures of different model proteins (HP-36 and $A\\beta$) resemble their respective real native state rather well. The dynamics of folding shows multistage decay, with an initial hydrophobic collapse followed by a long plateau. Analysis of $N_{topo}$ and RCO correlates the late stage folding with rearrangement of the side chain residues, particularly those far apart in the sequence. The long plateau also signifies large entropic free energy barrier near the native state, as predicted from theories of protein folding.

  14. Measurement of alpha- and beta-secretase cleaved amyloid precursor protein in cerebrospinal fluid from Alzheimer patients

    DEFF Research Database (Denmark)

    Sjögren, Magnus; Andreasen, Niels

    2003-01-01

    One of the major histopathological hallmarks of Alzheimer's disease (AD) is redundant senile plaques mainly composed of beta-amyloid (Abeta) aggregates. Alternative cleavage of the amyloid precursor protein (APP), occurring in both normal and AD subjects, results in the generation and secretion of soluble APP (sAPP) and Abeta. We examined the cerebrospinal fluid (CSF) for alpha- and beta-secretase cleaved sAPP (alpha-sAPP and beta-sAPP) in 81 sporadic AD patients, 19 patients with mild cognitive impairment, and 42 healthy controls by using newly developed sandwich enzyme-linked immunosorbent assay methods. We found that neither the level of CSF-alpha-sAPP nor CSF-beta-sAPP differed between sporadic AD patients and healthy controls. These findings further support the conclusion that there is no change in APP expression in sporadic AD. However, the level of CSF-beta-sAPP was significantly increased in patients with mild cognitive impairment compared to controls. We also investigated the relationship between the CSF level of alpha/beta-sAPP and Abeta(42) and the apoE epsilon 4 (apoE4) allele. Significantly lower levels of CSF-alpha-sAPP were found in AD patients possessing one or two apoE4 alleles than in those not possessing the apoE4 allele. Neither the levels of CSF-beta-sAPP nor CSF-Abeta(42) differed when comparing ApoE4 allele-positive with allele-negative individuals.

  15. Amyloid protein-mediated differential DNA methylation status regulates gene expression in Alzheimer’s disease model cell line

    International Nuclear Information System (INIS)

    Highlights: ? Genome-wide DNA methylation pattern in Alzheimer’s disease model cell line. ? Integrated analysis of CpG methylation and mRNA expression profiles. ? Identify three Swedish mutant target genes; CTIF, NXT2 and DDR2 gene. ? The effect of Swedish mutation on alteration of DNA methylation and gene expression. -- Abstract: The Swedish mutation of amyloid precursor protein (APP-sw) has been reported to dramatically increase beta amyloid production through aberrant cleavage at the beta secretase site, causing early-onset Alzheimer’s disease (AD). DNA methylation has been reported to be associated with AD pathogenesis, but the underlying molecular mechanism of APP-sw-mediated epigenetic alterations in AD pathogenesis remains largely unknown. We analyzed genome-wide interplay between promoter CpG DNA methylation and gene expression in an APP-sw-expressing AD model cell line. To identify genes whose expression was regulated by DNA methylation status, we performed integrated analysis of CpG methylation and mRNA expression profiles, and identified three target genes of the APP-sw mutant; hypomethylated CTIF (CBP80/CBP20-dependent translation initiation factor) and NXT2 (nuclear exporting factor 2), and hypermethylated DDR2 (discoidin domain receptor 2). Treatment with the demethylating agent 5-aza-2?-deoxycytidine restored mRNA expression of these three genes, implying methylation-dependent transcriptional regulation. The profound alteration in the methylation status was detected at the ?435, ?295, and ?271 CpG sites of CTIF, and at the ?505 to ?341 region in the promoter of DDR2. In the promoter region of NXT2, only one CpG site located at ?432 was differentially unmethylated in APP-sw cells. Thus, we demonstrated the effect of the APP-sw mutation on alteration of DNA methylation and subsequent gene expression. This epigenetic regulatory mechanism may contribute to the pathogenesis of AD.

  16. A time-resolved immunoassay to measure serum antibodies to the rotavirus VP6 capsid protein

    OpenAIRE

    Kavanagh, Owen; Zeng, Xi-Lei; Ramani, Sasirekha; Mukhopadhya, Indrani; Crawford, Sue E; Kang, Gagandeep; Estes, Mary K

    2013-01-01

    ? Two recombinant VP6 capsid proteins from an Indian birth cohort were expressed. ? The proteins were used to establish a time-resolved fluorescence DELFIA. ? DELFIA was compared to a gold standard ELISA using cohort serum samples. ? A significant association was observed between the two assays (p 

  17. Characterization of the beta amyloid precursor protein-like gene in the central nervous system of the crab Chasmagnathus. Expression during memory consolidation

    Directory of Open Access Journals (Sweden)

    Fustiñana Maria

    2010-09-01

    Full Text Available Abstract Background Human ?-amyloid, the main component in the neuritic plaques found in patients with Alzheimer's disease, is generated by cleavage of the ?-amyloid precursor protein. Beyond the role in pathology, members of this protein family are synaptic proteins and have been associated with synaptogenesis, neuronal plasticity and memory, both in vertebrates and in invertebrates. Consolidation is necessary to convert a short-term labile memory to a long-term and stable form. During consolidation, gene expression and de novo protein synthesis are regulated in order to produce key proteins for the maintenance of plastic changes produced during the acquisition of new information. Results Here we partially cloned and sequenced the beta-amyloid precursor protein like gene homologue in the crab Chasmagnathus (cappl, showing a 37% of identity with the fruit fly Drosophila melanogaster homologue and 23% with Homo sapiens but with much higher degree of sequence similarity in certain regions. We observed a wide distribution of cappl mRNA in the nervous system as well as in muscle and gills. The protein localized in all tissues analyzed with the exception of muscle. Immunofluorescence revealed localization of cAPPL in associative and sensory brain areas. We studied gene and protein expression during long-term memory consolidation using a well characterized memory model: the context-signal associative memory in this crab species. mRNA levels varied at different time points during long-term memory consolidation and correlated with cAPPL protein levels Conclusions cAPPL mRNA and protein is widely distributed in the central nervous system of the crab and the time course of expression suggests a role of cAPPL during long-term memory formation.

  18. Mitogen-activated protein kinase signaling pathways promote low-density lipoprotein receptor-related protein 1-mediated internalization of beta-amyloid protein in primary cortical neurons.

    Science.gov (United States)

    Yang, Wei-Na; Ma, Kai-Ge; Qian, Yi-Hua; Zhang, Jian-Shui; Feng, Gai-Feng; Shi, Li-Li; Zhang, Zhi-Chao; Liu, Zhao-Hui

    2015-07-01

    Mounting evidence suggests that the pathological hallmarks of Alzheimer's disease (AD) are caused by the intraneuronal accumulation of beta-amyloid protein (A?). Reuptake of extracellular A? is believed to contribute significantly to the intraneuronal A? pool in the early stages of AD. Published reports have claimed that the low-density lipoprotein receptor-related protein 1 (LRP1) mediates A?1-42 uptake and lysosomal trafficking in GT1-7 neuronal cells and mouse embryonic fibroblast non-neuronal cells. However, there is no direct evidence supporting the role of LRP1 in A? internalization in primary neurons. Our recent study indicated that p38 MAPK and ERK1/2 signaling pathways are involved in regulating ?7 nicotinic acetylcholine receptor (?7nAChR)-mediated A?1-42 uptake in SH-SY5Y cells. This study was designed to explore the regulation of MAPK signaling pathways on LRP1-mediated A? internalization in neurons. We found that extracellular A?1-42 oligomers could be internalized into endosomes/lysosomes and mitochondria in cortical neurons. A?1-42 and LRP1 were also found co-localized in neurons during A?1-42 internalization, and they could form A?1-42-LRP1 complex. Knockdown of LRP1 expression significantly decreased neuronal A?1-42 internalization. Finally, we identified that p38 MAPK and ERK1/2 signaling pathways regulated the internalization of A?1-42 via LRP1. Therefore, these results demonstrated that LRP1, p38 MAPK and ERK1/2 mediated the internalization of A?1-42 in neurons and provided evidence that blockade of LRP1 or inhibitions of MAPK signaling pathways might be a potential approach to lowering brain A? levels and served a potential therapeutic target for AD. PMID:25936756

  19. Association of Serum C-Reactive Protein (CRP) with Some Nutritional Parameters of Maintenance Hemodialysis Patients

    OpenAIRE

    Azar Baradaran; Hamid Nasri

    2005-01-01

    Malnutrition and inflammation are common in hemodialysis patients, and are usually closely associated. Serum C-reactive protein (CRP) concentrations have been found to be significantly elevated in hemodialysis patients and reflects chronic inflammation, and as an acute-phase reactant, is a sensitive and independent marker of malnutrition. To investigate the association of serum CRP level with some nutritional variables in diabetic and non diabetic end-stage renal failure patients under...

  20. CE can identify small molecules that selectively target soluble oligomers of amyloid beta protein and display antifibrillogenic activity.

    Science.gov (United States)

    Colombo, Raffaella; Carotti, Angelo; Catto, Marco; Racchi, Marco; Lanni, Cristina; Verga, Laura; Caccialanza, Gabriele; De Lorenzi, Ersilia

    2009-04-01

    Soluble and toxic oligomers of amyloid beta (A beta) protein have been identified as the true neurotoxic species involved in Alzheimer's disease and considering them as targets to inhibit A beta aggregation might have a therapeutic value. We previously set up a CE method that enables the separation and quantification of transient oligomers of A beta protein-containing 42 amino acids (A beta(1-42)) along the pathway leading to fibrils and we now demonstrate how this method can be successfully applied to examine the in vitro inhibitory effects of small molecules on A beta oligomerization. To this end, we investigated mitoxantrone and pixantrone, two well-known anticancer drugs, as well as suramin and a suramin-like compound. By using CE, it is here shown how mitoxantrone and pixantrone either reduce or block A beta(1-42) oligomerization, while Thioflavin T spectrofluorimetric assay and transmission electron microscopy demonstrate how these two compounds also display antifibrillogenic activity. Interestingly, in vitro cell viability experiments indicated that pixantrone significantly reduces A beta(1-42) neurotoxicity. PMID:19306269

  1. Elevated glucose and oligomeric ?-amyloid disrupt synapses via a common pathway of aberrant protein S-nitrosylation.

    Science.gov (United States)

    Akhtar, Mohd Waseem; Sanz-Blasco, Sara; Dolatabadi, Nima; Parker, James; Chon, Kevin; Lee, Michelle S; Soussou, Walid; McKercher, Scott R; Ambasudhan, Rajesh; Nakamura, Tomohiro; Lipton, Stuart A

    2016-01-01

    Metabolic syndrome (MetS) and Type 2 diabetes mellitus (T2DM) increase risk for Alzheimer's disease (AD). The molecular mechanism for this association remains poorly defined. Here we report in human and rodent tissues that elevated glucose, as found in MetS/T2DM, and oligomeric ?-amyloid (A?) peptide, thought to be a key mediator of AD, coordinately increase neuronal Ca(2+) and nitric oxide (NO) in an NMDA receptor-dependent manner. The increase in NO results in S-nitrosylation of insulin-degrading enzyme (IDE) and dynamin-related protein 1 (Drp1), thus inhibiting insulin and A? catabolism as well as hyperactivating mitochondrial fission machinery. Consequent elevation in A? levels and compromise in mitochondrial bioenergetics result in dysfunctional synaptic plasticity and synapse loss in cortical and hippocampal neurons. The NMDA receptor antagonist memantine attenuates these effects. Our studies show that redox-mediated posttranslational modification of brain proteins link A? and hyperglycaemia to cognitive dysfunction in MetS/T2DM and AD. PMID:26743041

  2. Low-density lipoprotein receptor-related protein-1 : a serial clearance homeostatic mechanism controlling Alzheimer's amyloid ?-peptide elimination from the brain

    OpenAIRE

    Zlokovic, Berislav V.; Deane, Rashid; Sagare, Abhay P.; Bell, Robert D; Winkler, Ethan A

    2010-01-01

    Low-density lipoprotein receptor-related protein-1 (LRP1), a member of the LDL receptor family, has major roles in the cellular transport of cholesterol, endocytosis of forty structurally diverse ligands, transcytosis of ligands across the blood-brain barrier, and transmembrane and nuclear signaling. Recent evidence indicates that LRP1 regulates brain and systemic clearance of Alzheimer's disease (AD) amyloid ?-peptide (A?). According to the two hit vascular hypothesis for AD, vascular damage...

  3. Heparan sulphate proteoglycan and the low-density lipoprotein receptor-related protein 1 constitute major pathways for neuronal amyloid-? uptake

    OpenAIRE

    Kanekiyo, Takahisa; ZHANG Juan; Qiang LIU; Liu, Chia-Chen; Zhang, Lijuan; Bu, Guojun

    2011-01-01

    Alzheimer’s disease (AD) is a progressive and irreversible neurodegenerative disorder in which the aggregation and deposition of amyloid-? (A?) peptides in the brain are central to its pathogenesis. In healthy brains, A? is effectively metabolized with little accumulation. Cellular uptake and subsequent degradation of A? is one of the major pathways for its clearance in the brain. Increasing evidence has demonstrated significant roles for the low-density lipoprotein receptor-related protein 1...

  4. Chronic treatment with amyloid beta(1-42) inhibits non-cholinergic high-affinity choline transport in NG108-15 cells through protein kinase C signaling.

    Czech Academy of Sciences Publication Activity Database

    Nováková, Jana; Mikasová, Lenka; Machová, Eva; Lisá, V?ra; Doležal, Vladimír

    2005-01-01

    Ro?. 1062, ?. 1-2 (2005), s. 101-110. ISSN 0006-8993 R&D Projects: GA AV ?R(CZ) IAA5011206; GA MŠk(CZ) LC554 Grant ostatní: Lipidiet(XE) QLK1-CT-2002-00172 Institutional research plan: CEZ:AV0Z50110509 Keywords : choline transporter * beta-amyloid * protein kinase C Subject RIV: ED - Physiology Impact factor: 2.296, year: 2005

  5. Identification of the Alzheimer's disease amyloid precursor protein (APP) and its homologue APLP2 as essential modulators of glucose and insulin homeostasis and growth.

    Science.gov (United States)

    Needham, B E; Wlodek, M E; Ciccotosto, G D; Fam, B C; Masters, C L; Proietto, J; Andrikopoulos, S; Cappai, R

    2008-06-01

    The amyloid precursor protein (APP), the source of the neurotoxic amyloid beta (A beta) peptide involved in Alzheimer's disease (AD), belongs to a conserved family of related proteins. In mammals, the APP family contains amyloid precursor-like protein 1 (APLP1) and amyloid precursor-like protein 2 (APLP2). Whilst a number of activities have been attributed to the APP family, an overall function has not been definitively established. While ablating either the APP or APLP2 gene in mice produces minimal phenotypic change, the combined knockout of these genes in mice causes postnatal mortality. Postnatal survival therefore requires a shared but unknown function of APP and APLP2. To investigate the biochemical basis for the postnatal lethality, plasma was analysed from double knockout mice (APP-/- APLP2-/-) 2 days before birth, at gestational day E17, and from mice at 12-16 h after birth. The postnatal double knockouts had 66% lower plasma glucose levels than their wild-type controls and 50% lower than their single knockout counterparts. Interestingly, the postnatal double knockouts displayed hyperinsulinaemia, as shown by inappropriate plasma insulin levels, given their degree of hypoglycaemia. The single knockout mice also showed hyperinsulinaemia and had 31% lower plasma glucose than the wild-types. While the double knockouts did not survive more than 24 h after birth, the single knockouts reached adulthood and their hypoglycaemia continued. Therefore, APP and APLP2 expression modulates plasma insulin and glucose concentrations. Plasma calcium, magnesium and phosphate were also significantly reduced in the double knockouts compared to the wild-types, and they showed distinctive growth restriction, suggesting the involvement of a metabolic impairment. These results link the expression of the APP and APLP2 genes with glucose homeostasis and growth and therefore identify a novel function for the APP family. PMID:18393365

  6. THE USE OF ELECTROPHORESIS IN LABORATORY DIAGNOSTIC OF SERUM PROTEINS IN VETERINARY MEDICINE

    OpenAIRE

    Veronika Nagyová; Csila Tóthová; Helena Šoltésová; Mária Vargová; Oskar Nagy

    2013-01-01

    In this study, we explain the need for more detailed laboratory diagnostic of serum proteins in veterinary medicine. The application of proteomic approaches over the last decade has provided new tools for clarifying the molecular aspects of physiological states, and for understanding the etiology and pathogenesis of many diseases. Proteomics performs large-scale protein analysis, describes the entire protein complement of a cell, tissue, biological fluid or organism and provides information o...

  7. Correlation between ocular Demodex infestation and serum immunoreactivity to bacillus proteins

    Directory of Open Access Journals (Sweden)

    Jian-Jing Li

    2015-06-01

    Full Text Available AIM: To investigate correlation between ocular Demodex infestation and serum immunoreactivity.METHODS:Demodex counting of 68 inpatients was performed based on eight lashes sampling. Serum immunoreactivity to two 62-kDa and 83-kDa proteins derived from B oleronius was determined by Western blot analysis.RESULTS: These 68 patients without facialrosacea or blepharitis were age matched(P=0.888and gender matched(P=0.595regarding serum immunoreactivity or ocular Demodex infestation. According to the eyelash, creep mite infection was divided into positive and negative groups, age-matched(P=0.590and sex-matched(P=0.329. There was no significant correlation between serum immunoreactivity and Demodex infestation(P=0.925. There were 27 patients with positive serum immunoreactivity in 38 patients with Demodex infestation(71%, and there were 21 patients in 30 patients without Demodex infestation(70%. There was no significant correlation between serum immunoreactivity and Demodex counting(P=0.758. CONCLUSION: It is unnecessary to perform serum analysis when Demodex can be found in asymptomatic individuals. But treatment of reducing lashes Demodex infestation is necessary when patient with blepharitis was detected Demodex in eye lashes and positive serum immunoreactivity.

  8. Protein heterodimerization through ligand-bridged multivalent pre-organization: enhancing ligand binding toward both protein targets.

    Science.gov (United States)

    Liu, Jiyun; Zhang, Zhongsheng; Tan, Xiaojian; Hol, Wim G J; Verlinde, Christophe L M J; Fan, Erkang

    2005-02-23

    Structure-based design of a bifunctional ligand for two protein pentamers, cholera toxin B pentamer (CTB) and human serum amyloid P component (SAP), leads to multivalent dimerization of CTB and SAP in solution. This multivalent heterodimerization of proteins significantly enhances the affinity of the bifunctional ligand toward both target proteins. PMID:15713072

  9. Relation between raised concentrations of fucose, sialic acid, and acute phase proteins in serum from patients with cancer: choosing suitable serum glycoprotein markers.

    OpenAIRE

    Turner, G.A.; Skillen, A W; Buamah, P; Guthrie, D.; Welsh, J; J. Harrison(School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom); Kowalski, A

    1985-01-01

    Serum concentrations of fucose, sialic acid, and eight acute phase proteins were measured in single specimens from patients with cancer in order to determine whether the raised concentrations of protein bound sugars commonly found in cancer correlate with increased concentrations of the acute phase proteins. Strong positive correlations were found only with alpha 1-acid glycoprotein, alpha 1-antitrypsin, and haptoglobins. Changes in protein bound sugars and acute phase proteins were also exam...

  10. Effect of acute irradiation on concentration of some serum proteins in rats

    Energy Technology Data Exchange (ETDEWEB)

    Chlebovska, K.; Liskova, E.; Chlebovsky, O.; Praslicka, M. (Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie)

    1981-01-01

    The relationship is studied between the effect of a dose of acute radiation and the character of changes in the serum concentration of prealbumin, albumin, A/sub 1/-globulin, A/sub 1/-macroglobulin (A/sub 1/M), transferrin, IgG, haptoglobin, ceruloplasmin, hemopexin, and the C/sub 3/ component of the complement in rats irradiated with doses of 1.91 Gy, 5.26 Gy and 6.70 Gy. With proteins whose serum concentrations decreased, the decrease was found to depend on the radiation dose. With proteins whose concentration increased as a result of irradiation, the most effective dose was found to be 5.26 Gy. The concentration of the serum proteins was determined by 2-dimensional immunoelectrophoresis.

  11. Serum-based protein biomarkers in blast-induced traumatic brain injury spectrum disorder

    Directory of Open Access Journals (Sweden)

    MohammadElsayed

    2012-07-01

    Full Text Available The biological consequences of exposure to explosive blast are extremely complex. Serum protein biomarkers in blast-induced TBI (bTBI can aid in determining injury severity, monitoring progress, and predicting outcome. Exposure to blast results in varying degrees of physical injury. Explosive blast can also induce psychological stress that can contribute to or amplify the extent of physical damage. Given the complexity, the scale of injury, and variety of symptoms, bTBI may be best described as a spectrum disorder. In this focused review, we summarize the status of serum protein biomarkers in bTBI in the context of the classification and pathological changes of other forms of TBI. Finally, we recommend specific and easily implementable measures to accelerate serum protein biomarker discovery and validation in bTBI.

  12. The relation of the individual variability of serum proteins to the mortality of rats after irradiation

    International Nuclear Information System (INIS)

    On the basis of the percentage of particular serum proteins, established prior to irradiation of rats by doses of 6.7, 7.17 and 8.13 Gy in comparison with their mortality, followed up to the 30th day after completing irradiation, the individual radiosensitivity of the animals was ascertained. The highest percentage of the mortality of irradiated rats after all the three doses was observed in groups with lower (30 to 50, 50 to 70%) and higher (130 to 150%) values of serum proteins. Maximum numbers of surviving rats were found in the central region (90 to 110%) of the variation interval of the values of serum proteins examined. (author)

  13. Effect of acute irradiation on concentration of some serum proteins in rats

    International Nuclear Information System (INIS)

    The relationship is studied between the effect of a dose of acute radiation and the character of changes in the serum concentration of prealbumin, albumin, A1-globulin, A1-macroglobulin (A1M), transferrin, IgG, haptoglobin, ceruloplasmin, hemopexin, and the C3 component of the complement in rats irradiated with doses of 1.91 Gy, 5.26 Gy and 6.70 Gy. With proteins whose serum concentrations decreased, the decrease was found to depend on the radiation dose. With proteins whose concentration increased as a result of irradiation, the most effective dose was found to be 5.26 Gy. The concentration of the serum proteins was determined by 2-dimensional immunoelectrophoresis. (author)

  14. Amyloid Deposits in Senile Vertebral Arteries, Immunohistological and Ultrastructural Findings

    Directory of Open Access Journals (Sweden)

    S. Doostkam

    2008-01-01

    Full Text Available In a study on amyloid deposits in vertebral arteries, many elderly patients showed amyloid deposits in the perivascular tissue. These proved to be senile systemic amyloidosis of the transthyretin-type by immunohistochemistry. Amyloid deposits were also found in the arterial wall. These intramural amyloid deposits showed significant affinity to elastic material of the arterial wall. The intramural amyloid deposits did not react with any of the known or available antibodies to amyloid subtypes. Only a polyclonal antibody to human elastin could mark this type of amyloid. It may therefore be assumed that the precursor protein of this amyloid is derived from elastin molecules. By electron microscopy, the light microscopic amyloid deposits were of fibrillary structure, typical for amyloid with a direct contact to elastic material.

  15. Kinetic studies on beta-site amyloid precursor protein-cleaving enzyme (BACE). Confirmation of an iso mechanism.

    Science.gov (United States)

    Toulokhonova, Larisa; Metzler, William J; Witmer, Mark R; Copeland, Robert A; Marcinkeviciene, Jovita

    2003-02-14

    The steady-state kinetic mechanism of beta-amyloid precursor protein-cleaving enzyme (BACE)-catalyzed proteolytic cleavage was evaluated using product and statine- (Stat(V)) or hydroxyethylene-containing (OM99-2) peptide inhibition data, solvent kinetic isotope effects, and proton NMR spectroscopy. The noncompetitive inhibition pattern observed for both cleavage products, together with the independence of Stat(V) inhibition on substrate concentration, suggests a uni-bi-iso kinetic mechanism. According to this mechanism, the enzyme undergoes multiple conformation changes during the catalytic cycle. If any of these steps are rate-limiting to turnover, an enzyme form preceding the rate-limiting conformational change should accumulate. An insignificant solvent kinetic isotope effect (SKIE) on k(cat)/K(m), a large inverse solvent kinetic isotope effect on k(cat), and the absence of any SKIE on the inhibition onset by Stat(V) during catalysis together indicate that the rate-limiting iso-step occurs after formation of a tetrahedral intermediate. A moderately short and strong hydrogen bond (at delta 13.0 ppm and phi of 0.6) has been observed by NMR spectroscopy in the enzyme-hydroxyethylene peptide (OM99-2) complex that presumably mimics the tetrahedral intermediate of catalysis. Collapse of this intermediate, involving multiple steps and interconversion of enzyme forms, has been suggested to impose a rate limitation, which is manifested in a significant SKIE on k(cat). Multiple enzyme forms and their distribution during catalysis were evaluated by measuring the SKIE on the noncompetitive (mixed) inhibition constants for the C-terminal reaction product. Large, normal SKIE values were observed for these inhibition constants, suggesting that both kinetic and thermodynamic components contribute to the K(ii) and K(is) expressions, as has been suggested for other iso-mechanism featuring enzymes. We propose that a conformational change related to the reprotonation of aspartates during or after the bond-breaking event is the rate-limiting segment in the catalytic reaction of beta-amyloid precursor protein-cleaving enzyme, and ligands binding to other than the ground-state forms of the enzyme might provide inhibitors of greater pharmacological relevance. PMID:12458195

  16. On the transfer of serum proteins to the rat intestinal juice

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Hansen, G H

    1994-01-01

    The in vivo pattern of serum proteins in the rat small-intestinal juice was characterized by crossed immunoelectrophoresis. Immunoglobulins and albumin, alpha-1-antitrypsin, transferrin, and orosomucoid were present. Larger serum proteins were absent (ceruloplasmin, haptoglobin, alpha-1-macroglobulin, alpha and beta lipoproteins). Thus, apart from immunoglobulins, only serum proteins with a molecular mass less than approximately 100 kDa were demonstrated. The origin and epithelial transfer were further characterized, using albumin as a model. No sign of local synthesis of albumin by the enterocytes was found by Northern blotting, and no albumin was found in the Golgi complex by immunogold electron microscopy. By immunogold electron microscopy a heavy labelling of albumin was observed in the interstitial spaces between the villus enterocytes. Where the enterocytes disintegrated, albumin was seen to leak out into the intestinal lumen from the opened interstitial spaces. A weak labelling was also found in the lysosomal/endosomal-like structures, especially in the crypt enterocytes, indicating pinocytosis of albumin. We conclude that the main reason for the occurrence of certain serum proteins in the intestinal juice is a selective passage through the capillary wall followed by passive intercellular transport via delivery of the serum in the interstitial space during disintegration of the enterocytes.

  17. Protein Clearance Mechanisms of Alpha-Synuclein and Amyloid-Beta in Lewy Body Disorders

    OpenAIRE

    Michela Deleidi; Walter Maetzler

    2012-01-01

    Protein clearance is critical for the maintenance of the integrity of neuronal cells, and there is accumulating evidence that in most—if not all—neurodegenerative disorders, impaired protein clearance fundamentally contributes to functional and structural alterations eventually leading to clinical symptoms. Dysfunction of protein clearance leads to intra- and extraneuronal accumulation of misfolded proteins and aggregates. The pathological hallmark of Lewy body disorders (LBDs) is the abnorma...

  18. Effect of water salinity on total protein and electrophoretic pattern of serum proteins of grass carp, Ctenopharyngodon idella

    OpenAIRE

    Peyghan, Rahim; Khadjeh, Gholam Hosain; Enayati, Ala

    2014-01-01

    In this study the effects of water salinity on serum total protein and its components in grass carp were investigated. The aim of this study was to determine the effect of salinity tolerance of fish on total serum protein level and its components as an indicator of liver and kidney activity. One hundred and twenty grass carp were divided into four groups, randomly. The first three groups were reared in concentration of 4, 8 and 12 g L-1 of salt solution, respectively, and the fourth group was...

  19. Interaction of the amyloid precursor protein-like protein 1 (APLP1) E2 domain with heparan sulfate involves two distinct binding modes

    International Nuclear Information System (INIS)

    Two X-ray structures of APLP1 E2 with and without a heparin dodecasaccharide are presented, revealing two distinct binding modes of the protein to heparan sulfate. The data provide a mechanistic explanation of how APP-like proteins bind to heparan sulfates and how they specifically recognize nonreducing structures of heparan sulfates. Beyond the pathology of Alzheimer’s disease, the members of the amyloid precursor protein (APP) family are essential for neuronal development and cell homeostasis in mammals. APP and its paralogues APP-like protein 1 (APLP1) and APP-like protein 2 (APLP2) contain the highly conserved heparan sulfate (HS) binding domain E2, which effects various (patho)physiological functions. Here, two crystal structures of the E2 domain of APLP1 are presented in the apo form and in complex with a heparin dodecasaccharide at 2.5 Å resolution. The apo structure of APLP1 E2 revealed an unfolded and hence flexible N-terminal helix ?A. The (APLP1 E2)2–(heparin)2 complex structure revealed two distinct binding modes, with APLP1 E2 explicitly recognizing the heparin terminus but also interacting with a continuous heparin chain. The latter only requires a certain register of the sugar moieties that fits to a positively charged surface patch and contributes to the general heparin-binding capability of APP-family proteins. Terminal binding of APLP1 E2 to heparin specifically involves a structure of the nonreducing end that is very similar to heparanase-processed HS chains. These data reveal a conserved mechanism for the binding of APP-family proteins to HS and imply a specific regulatory role of HS modifications in the biology of APP and APP-like proteins

  20. Interaction of the amyloid precursor protein-like protein 1 (APLP1) E2 domain with heparan sulfate involves two distinct binding modes

    Energy Technology Data Exchange (ETDEWEB)

    Dahms, Sven O., E-mail: sdahms@fli-leibniz.de [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany); Mayer, Magnus C. [Freie Universität Berlin, Thielallee 63, 14195 Berlin (Germany); Miltenyi Biotec GmbH, Robert-Koch-Strasse 1, 17166 Teterow (Germany); Roeser, Dirk [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany); Multhaup, Gerd [McGill University Montreal, Montreal, Quebec H3G 1Y6 (Canada); Than, Manuel E., E-mail: sdahms@fli-leibniz.de [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany)

    2015-03-01

    Two X-ray structures of APLP1 E2 with and without a heparin dodecasaccharide are presented, revealing two distinct binding modes of the protein to heparan sulfate. The data provide a mechanistic explanation of how APP-like proteins bind to heparan sulfates and how they specifically recognize nonreducing structures of heparan sulfates. Beyond the pathology of Alzheimer’s disease, the members of the amyloid precursor protein (APP) family are essential for neuronal development and cell homeostasis in mammals. APP and its paralogues APP-like protein 1 (APLP1) and APP-like protein 2 (APLP2) contain the highly conserved heparan sulfate (HS) binding domain E2, which effects various (patho)physiological functions. Here, two crystal structures of the E2 domain of APLP1 are presented in the apo form and in complex with a heparin dodecasaccharide at 2.5 Å resolution. The apo structure of APLP1 E2 revealed an unfolded and hence flexible N-terminal helix ?A. The (APLP1 E2){sub 2}–(heparin){sub 2} complex structure revealed two distinct binding modes, with APLP1 E2 explicitly recognizing the heparin terminus but also interacting with a continuous heparin chain. The latter only requires a certain register of the sugar moieties that fits to a positively charged surface patch and contributes to the general heparin-binding capability of APP-family proteins. Terminal binding of APLP1 E2 to heparin specifically involves a structure of the nonreducing end that is very similar to heparanase-processed HS chains. These data reveal a conserved mechanism for the binding of APP-family proteins to HS and imply a specific regulatory role of HS modifications in the biology of APP and APP-like proteins.

  1. The serum protein carbonyl content level in relation to exercise stress test

    Directory of Open Access Journals (Sweden)

    Titiporn Mekrungruangwong

    2012-01-01

    Full Text Available Background: Protein carbonyl (P is oxidatively-modified protein with diagnostic potential for acute myocardial infarction. However, many findings indicated the elevation of serum PC content level related to exercise, which could cause false positive results and limiting the specificity for acute coronary syndrome diagnosis. This study aims to evaluate the level of serum protein carbonyl content in healthy volunteers subjected to exercise stress test (EST. Materials and Methods: Serum from healthy volunteers was collected 5-10 min before performing EST and 1 hour after the EST was achieved. The serum was collected, and the serum PC content level was determined by spectrophotometric DNPH assay. Results: The serum PC content level after exercise stress test was significantly higher than that of before performing EST (0.373 ± 0.05 nM/mg vs. 0.275 ± 0.02 nM/mg, P < 0.0001. The results demonstrated that in both male and female, serum PC content level after EST was significantly higher than that of before performing EST (0.29 ± 0.03 nM/mg vs. 0.36 ± 0.05 nM/mg P < 0.0001 in male, 0.27 ± 0.02 nM/mg vs. 0.38 ± 0.06 nM/mg P < 0.0001 in female, respectively. Conclusions: This study demonstrated that exercise stress test could result in non-specificity and false positive increasing in serum PC content level in healthy subjects, which may cause misinterpretation when using PC as cardiac marker, especially in patients, who underwent exercise stress test or patients who performing heavy physical activities.

  2. ANTIAMNESIC POTENTIAL OF SOLASODINE AGAINST ?-AMYLOID PROTEIN INDUCED AMNESIA IN MICE

    Directory of Open Access Journals (Sweden)

    Desai Alpesh B

    2011-05-01

    Full Text Available Alzheimer’s disease (AD, the most common form of dementia in the elderly population, is characterized by an insidious onset with memory impairment and an inexorable progression of cognitive decline. Nootropic agents are a heterogeneous groups of drugs developed for use in dementia and other cerebral disorders. Nootropics agents are being primarily used to improve memory, mood and behavior. However, the resulting adverse effects associated with these agents have limited their use. Therefore, it is worthwhile to explore the utility of traditional medicines for the treatment of various cognitive disorders. The present study was undertaken to assess the potential of solasodine on ?-amyloid induced amnesia in mice. Elevated plus maze (EPM and Morris water maze (MWM was employed to evaluate learning and memory parameters. Piracetam was used as the standard drug. Solasodine (1, 2 and 4 mg/kg, p.o. was screened for claimed potential in mice. Solasodine improved both short term memory and long term memory when assessed on Elevated pluz maze and Morris Water maze respectively. Hence, solasodine might prove to be a useful memory restorative agent in the treatment of dementia seen in the Alzheimer’s disease.

  3. Hyperphosphorylated tau and amyloid precursor protein deposition is increased in the brains of young drug abusers.

    Science.gov (United States)

    Ramage, S N; Anthony, I C; Carnie, F W; Busuttil, A; Robertson, R; Bell, J E

    2005-08-01

    Drug abuse is a major problem worldwide. The incidence of drug-related deaths attributed to opiate abuse is increasing annually. Apart from routine examination, little is known of the neuropathology of drug abuse. We, and others, have shown previously that drug abuse is associated with microglial activation. We hypothesised that neuroinflammation might lead to premature neurodegeneration in drug abusers. We investigated the brains of young opiate abusers (n=34, allabusers. These were not only more prevalent in the drug abusers than in controls (44%vs. 19%) but also involved more brain areas. In controls NFT were confined to the entorhinal cortex whereas in drug users they were also found in the subiculum, temporal neocortex, nucleus basalis of Meynert and the locus coeruleus. Virtually no amyloid plaques were present but betaAPP positivity was again much more common in drug abusers than controls (73%vs. 20% in the brainstem and 59%vs. 23% in the temporal lobe). There is no suggestion that these drug abusers had displayed major cognitive impairment although detailed neuropsychological assessment is difficult in this subject group. Likely causes of hyperphosphorylated tau deposition in drug abuse include hypoxic-ischaemic injury, microglial-associated cytokine release and possibly drug-associated neurotoxicity or hepatitis. Head injury, which is another major risk factor, does not appear to have contributed to our findings. Genetic factors also merit consideration. It is unclear at present how much of the hyperphosphorylated tau detected in these young drug abusers represents a transitory phenomenon. PMID:16008828

  4. Tracer diffusion coefficients of proteins by means of holographic relaxation spectroscopy: application to bovine serum albumin

    International Nuclear Information System (INIS)

    Holographic relaxation spectroscopy has been used to measure tracer diffusion coefficients for photochromically labeled bovine serum albumin in solutions having total bovine serum albumin concentrations in the range 3.25 to 257 g/liter. In the limit of zero concentration, the diffusion coefficient was found to be 5.9 X 10(-7) cm2/s and the initial slope was zero. The concentration dependence of the diffusion coefficient was not significantly affected by the fraction of protein molecules which were labeled. Holographic relaxation spectroscopy permits rapid, accurate determination of tracer diffusion coefficients for proteins in mixtures

  5. Serum Advanced Oxidation Protein Products in Oral Squamous Cell Carcinoma: Possible Markers of Diagnostic Significance

    Directory of Open Access Journals (Sweden)

    Abhishek Singh Nayyar

    2013-07-01

    Full Text Available Background: The aim of this study was to measure the concentrations (levels ofserum total proteins and advanced oxidation protein products as markers of oxidantmediated protein damage in the sera of patients with oral cancers.Methods: The study consisted of the sera analyses of serum total protein andadvanced oxidation protein products’ levels in 30 age and sex matched controls, 60patients with reported pre-cancerous lesions and/or conditions and 60 patients withhistologically proven oral squamous cell carcinoma. One way analyses of variance wereused to test the difference between groups. To determine which of the two groups’ meanswere significantly different, the post-hoc test of Bonferroni was used. The results wereaveraged as mean ± standard deviation. In the above test, P values less than 0.05 weretaken to be statistically significant. The normality of data was checked before thestatistical analysis was performed.Results: The study revealed statistically significant variations in serum levels ofadvanced oxidation protein products (P<0.001. Serum levels of total protein showedextensive variations; therefore the results were largely inconclusive and statisticallyinsignificant.Conclusion: The results emphasize the need for more studies with larger samplesizes to be conducted before a conclusive role can be determined for sera levels of totalprotein and advanced oxidation protein products as markers both for diagnosticsignificance and the transition from the various oral pre-cancerous lesions and conditionsinto frank oral cancers.

  6. Studies on serum protein fractions of patients with uterine cervical cancer undergoing radiotherapy. Relationship between changes in serum protein fractions and prognosis

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the correlation between changes in serum protein fractions and patient prognosis. The subjects were 84 patients with uterine cervical cancer treated with combined external pelvic irradiation and intracavitary irradiation using a remote afterloading system (RALS). Twenty one normal women served as controls. Serum levels of 23 protein components were determined before and after radiotherapy. All patients were followed up for 4 to 8 years after radiotherapy. Pretreatment serum levels of prealbumin (Prealb), ?2HS glycoprotein (?2HS), ?2-plasmin inhibitor (?2PI), transferrin (Tf), plasminogen (Pmg), albumin (Alb), IgM, and hemopexin (Hx) were significantly lower in the group of cervical cancer patients than the control group; and serum levels of ?1-antichymotrypsin (?1X), haptoglobin (Hp), C9, fibrinogen (Fib), ceruloplasmin (Cp), ?1-acid glycoprotein (?1AG), ?1-antitrypsin (?1AT), and C4 were elevated. At the completion of radiotherapy, HP, C4, and Fib levels were significantly lower than those before radiotherapy; Prealb, ?2HS, and ?2PI were elevated. In patients who survived 4 years and 8 years, pretreatment levels of Cp, ?1AG, Hp, and C9 were significantly reduced and Tf was elevated, as compared with those who died within 4 years. In those who survived more than 4 years, posttreatment levels of ?1AT, Hp, ?1X, Cp, and C9 were significantly reduced, although the serum level of C4 was elevated. Survival positively correlated with pretreatment levels of Tf, Pmg, and ?1AT, but negatively correlated with AT III, Cp, C1Inh, IgA, ?1AG, and C9. For posttreatment levels, it positively correlated with Pmg, C4, Prealb, Alb, ?2M, and Hp, but negatively correlated with Tf, ?2PI, AT III, ?1AT, C1Inh, C9, and IgA. (N.K.)

  7. A preliminary study on the serum protein response in canine babesiosis : research communication

    Directory of Open Access Journals (Sweden)

    R.G. Lobetti

    2000-07-01

    Full Text Available Total serum protein, albumin, globulin, globulin fractions (alpha, beta and gamma globulins and an acute-phase protein ((alpha1-acid glycoprotein were evaluated in dogs with naturally occurring mild (Group 1, severe (Group 2 or complicated babesiosis (Group 3. Results showed that the total serumprotein, albumin, A/G ratio and (alphaglobulins were statistically different between Groups 1 and 2. There was no statistical difference between groups with total, (betaand (gamma globulins. The findings from this study suggest that dogs with mild and severe babesiosis had low total serum proteins, albumin, A/G ratio and (alpha globulins; dogs with complicated babesiosis showed no typical serum protein changes or patterns; and that there was no evidence of an acute-phase response detectable on serum protein electrophoresis in any of the 3 groups. A marked acute-phase response was, however, present, as measured by the (alpha1-acid glycoprotein, in all 3 groups. As this was a retrospective study, the possibility that the observed responses were due in part to concurrent disease could not be excluded.

  8. Clinical significance of serum S-100B protein levels in the grading of brain injury

    International Nuclear Information System (INIS)

    Objective: To investigate the clinical significance of determination of serum S-100B protein levels in the grading of brain injury. Methods: Eighty patients with brain injury were classified in to three grades according to the Glascow score: 13-15, minor grade n=30; 9-12, moderate, n=25; 3-8, severe n=25. Serum S-100B protein levels were measured with EL ISA in these patients 6h after the injury and daily thereafter for 3-7 days. Results: The mean concentrations of serum S-100B protein in these patients were as followings ; minor grade, 0.35 ± 0.13 ?g/L; moderate grade, 0.77 ± 0.20 ?g/L; severe grade 1.12 ± 0.30 ?g/L (differences among them being significant, P<0.005). The S-100B protein levels were negatively correlated with the Glascow score. Conclusion: Serum concentrations of S - 100B protein is an ideal screening bio-marker for the severity of brain injury. (authors)

  9. Low Serum Level ?-Synuclein and Tau Protein in Autism Spectrum Disorder Compared to Controls.

    Science.gov (United States)

    Kadak, Muhammed Tayyib; Cetin, Ihsan; Tarakç?o?lu, Mahmut Cem; Özer, Ömer Faruk; Kaçar, Selma; Çimen, Behzat

    2015-12-01

    ?-Synuclein (?-syn) and tau proteins are thought to be related with the synaptic loss and cell death underlying several important neurodegenerative diseases. The aim of our study was to investigate serum ?-syn and tau levels in autism. Serum levels of ?-syn and tau were measured, and autism spectrum disorder (ASD) severity was assessed at admission using the Childhood Autism Rating Scale (CARS) total score. The mean CARS score of the autism group on admission was 47.91 points (SD: 5.97). The results indicated that the mean serum ?-syn and serum tau levels were significantly (p?children with ASD as compared with normal cases (33.01?±?20.78 and 55.19?±?15.34 ng/mL and 241.23?±?290.5 and 509.78?±?269.25 ng/mL, respectively). There was a significant positive correlation between serum ?-syn levels and serum levels of tau identified by Pearson correlation analysis (r?=?0.922, n?=?28, p?autism may result from microglial activity. Furthermore, ?-syn and tau aggregation may lead to synaptic dysfunction, and this may contribute to either neuronal or synaptic dysfunction or neurodegeneration. Our preliminary study suggests that low levels of serum ?-syn and tau may be implicated in the relationship between synaptic activity and autism. PMID:26479762

  10. Serum glial fibrillary acidic protein as a specific marker for necrotizing meningoencephalitis in Pug dogs.

    Science.gov (United States)

    Miyake, Hizuru; Inoue, Akiko; Tanaka, Miho; Matsuki, Naoaki

    2013-11-01

    To evaluate the ability of serum glial fibrillary acidic protein (GFAP) concentration as a diagnostic marker for canine central nervous system (CNS) disorders, sera from dogs with various CNS (n=47) and non-CNS (n=56) disorders were measured for GFAP by using an ELISA kit. Healthy Beagles (n=15) and Pug dogs (n=12) were also examined as controls. Interestingly, only Pug dogs with necrotizing meningoencephalitis (NME) showed elevated serum GFAP concentrations (dogs with NME did not. Among the Pug dogs with NME, serum GFAP concentrations did not correlate with their clinical features, such as ages or survival times. Our data indicate the usefulness of serum GFAP as a novel marker for Pug dogs with NME. PMID:23856761

  11. The correlation study of serum retinol binding protein 4 and atherosclerosis in type 2 diabetes

    International Nuclear Information System (INIS)

    Objective: To evaluate the association of Retinol binding protein 4(RBP4) with carotid atherosclerosis in type 2 diabetes mellitus (T2DM). Methods: ELISA was used to detect the serum RBP4 level in 100 T2DM in 39 of which carotid atherosclerosis was observed and in the 30 controls, transthyretin (TTR) and other clinical index were also tested. Results: Serum RBP4 level and RBP4/ TTR were significantly higher in T2DM with/without carotid atherosclerosis than that in the controls (P0, OR>1, P<0.1). Conclusion: Serum RBP4 may be a novel risk factor for diabetes with atherosclerosis. Importantly, the RBP4/TTR ratio is more valuable than serum RBP4 concentration to used to evaluate risk factor for carotid atherosclerosis in T2DM. (authors)

  12. Agregados amiloides: rol en desórdenes de conformación proteica / Amyloid aggregates: role in protein misfolding disorders

    Scientific Electronic Library Online (English)

    Claudia, Duran-Aniotz; Inés, Moreno-Gonzalez; Rodrigo, Morales.

    2013-04-01

    Full Text Available [...] Abstract in english Misfolding and aggregation of proteins are the main features of a group of diseases termed Protein Misfolding Disorders (PMDs). PMDs include Alzheimer's disease and Transmissible Spongiform Encephalopathies, among many others. The deposition of protein aggregates is the main responsible for tissue d [...] amage and the consequent clinical signs generated in such disorders. In this review, we will focus in the role of protein aggregates in these diseases and in the putative mechanisms by which they exert their toxicity.

  13. The low-density lipoprotein receptor-related protein 1 and amyloid-? clearance in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Takahisa Kanekiyo

    2014-05-01

    Full Text Available Accumulation and aggregation of amyloid-? (A? peptides in the brain trigger the development of progressive neurodegeneration and dementia associated with Alzheimer’s disease (AD. Perturbation in A? clearance, rather than A? production, is likely the cause of sporadic, late-onset AD, which accounts for the majority of AD cases. Since cellular uptake and subsequent degradation constitute a major A? clearance pathway, the receptor-mediated endocytosis of A? has been intensely investigated. Among A? receptors, the low-density lipoprotein receptor-related protein 1 (LRP1 is one of the most studied receptors. LRP1 is a large endocytic receptor for more than 40 ligands, including apolipoprotein E (apoE, ?2-macroglobulin and A?. Emerging in vitro and in vivo evidence demonstrates that LRP1 is critically involved in brain A? clearance. LRP1 is highly expressed in a variety of cell types in the brain including neurons, vascular cells and glial cells, where LRP1 functions to maintain brain homeostasis and control A? metabolism. LRP1-mediated endocytosis regulates cellular A? uptake by binding to A? either directly or indirectly through its co-receptors or ligands. Furthermore, LRP1 regulates several signaling pathways, which also likely influences A? endocytic pathways. In this review, we discuss how LRP1 regulates the brain A? clearance and how this unique endocytic receptor participates in AD pathogenesis. Understanding of the mechanisms underlying LRP1-mediated A? clearance should enable the rational design of novel diagnostic and therapeutic strategies for AD.

  14. Solid-state NMR analysis of the {beta}-strand orientation of the protofibrils of amyloid {beta}-protein

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Takashi [Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Masuda, Yuichi, E-mail: masuda@mail.pharm.tohoku.ac.jp [Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578 (Japan); Irie, Kazuhiro [Graduate School of Agriculture, Kyoto University, Kyoto 606-8502 (Japan); Akagi, Ken-ichi; Monobe, Youko; Imazawa, Takayoshi [Section of Laboratory Equipment, Division of Biomedical Research, National Institute of Biomedical Innovation, Osaka 567-0085 (Japan); Takegoshi, K. [Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer The supramolecular structure of A{beta}42 protofibrils was analyzed by solid-state NMR. Black-Right-Pointing-Pointer The Ala-21 residue in the A{beta}42 protofibrils is included in a slightly disordered {beta}-strand. Black-Right-Pointing-Pointer The A{beta}42 protofibrils do not form intermolecular in-register parallel {beta}-sheets. -- Abstract: Alzheimer's disease (AD) is caused by abnormal deposition (fibrillation) of a 42-residue amyloid {beta}-protein (A{beta}42) in the brain. During the process of fibrillation, the A{beta}42 takes the form of protofibrils with strong neurotoxicity, and is thus believed to play a crucial role in the pathogenesis of AD. To elucidate the supramolecular structure of the A{beta}42 protofibrils, the intermolecular proximity of the Ala-21 residues in the A{beta}42 protofibrils was analyzed by {sup 13}C-{sup 13}C rotational resonance experiments in the solid state. Unlike the A{beta}42 fibrils, an intermolecular {sup 13}C-{sup 13}C correlation was not found in the A{beta}42 protofibrils. This result suggests that the {beta}-strands of the A{beta}42 protofibrils are not in an in-register parallel orientation. A{beta}42 monomers would assemble to form protofibrils with the {beta}-strand conformation, then transform into fibrils by forming intermolecular parallel {beta}-sheets.

  15. Nanoscale size dependence in the conjugation of amyloid beta and ovalbumin proteins on the surface of gold colloidal particles

    International Nuclear Information System (INIS)

    Absorption spectroscopy was utilized to investigate the conjugation of amyloid ? protein solution (A?1-40) and chicken egg albumin (ovalbumin) with various sizes of gold colloidal nanoparticles for various pHs, ranging from pH 2 to pH 10. The pH value that indicates the colour change, pHo, exhibited colloidal size dependence for both A?1-40 and ovalbumin coated particles. In particular, A?1-40 coated gold colloidal particles exhibited non-continuous size dependence peaking at 40 and 80 nm, implying that their corresponding cage-like structures provide efficient net charge cancellation at these core sizes. Remarkably, only the pHo value for ovalbumin coated 80 nm gold colloid was pH>7, and a specific cage-like structure is speculated to have a positive net charge facing outward when ovalbumin self-assembles over this particular gold colloid. The previously reported reversible colour change between pH 4 and 10 took place only with A?1-40 coated 20 nm gold colloids; this was also explored with ovalbumin coated gold colloids. Interestingly, gold colloidal nanoparticles showed a quasi-reversible colour change when they were coated with ovalbumin for all test sizes. The ovalbumin coated gold colloid was found to maintain reversible properties longer than A?1-40 coated gold colloid

  16. Endogenous secreted amyloid precursor protein-alpha regulates hippocampal NMDA receptor function, long-term potentiation and spatial memory.

    Science.gov (United States)

    Taylor, Chanel J; Ireland, David R; Ballagh, Irene; Bourne, Katie; Marechal, Nicola M; Turner, Paul R; Bilkey, David K; Tate, Warren P; Abraham, Wickliffe C

    2008-08-01

    Secreted amyloid precursor protein-alpha (sAPP alpha) levels are reduced during the pathogenesis of Alzheimer's disease, but the significance of this for neural function is not well understood. Here, we show that intrahippocampal infusion of antibodies targeted to endogenous sAPP alpha reduced long-term potentiation (LTP) in the dentate gyrus of adult rats by approximately 50%. Conversely, infusion of recombinant sAPP alpha dose-dependently increased LTP and facilitated in vitro tetanically evoked NMDA receptor-mediated currents. Pharmacological inhibition of alpha-secretase and other a-disintegrin-and-metalloproteases by TAPI-1 reduced both LTP and tetanus-evoked NMDA receptor-mediated currents in dentate granule cells. Both effects were prevented by co-application of exogenous recombinant sAPP alpha. Similarly, spatial memory was inhibited by intrahippocampal TAPI-1, an effect that was prevented by co-application of recombinant sAPP alpha. Together these findings indicate that endogenous sAPP alpha is a key contributor to synaptic plasticity and spatial memory. Its reduced production in Alzheimer's disease may thus contribute to the clinical memory deficits. PMID:18585048

  17. Growth regulation of rat thyrocytes (FRTL-5 cells) by the secreted ectodomain of beta-amyloid precursor-like proteins.

    Science.gov (United States)

    Popp, G M; Graebert, K S; Pietrzik, C U; Rosentreter, S M; Lemansky, P; Herzog, V

    1996-05-01

    The TSH-dependent expression of amyloid precursor-like proteins and the secretion of their ectodomain (sAPP) in rat thyroids coincide with increased rates of thyrocyte proliferation. To analyze whether the secretion of sAPP and the proliferation of thyrocytes are regulatorily linked, we employed [3H]thymidine or 5-bromo-2'-deoxyuridine assays and found that conditioned culture medium stimulated the proliferation of FRTL-5 cells depending on the content of sAPP. These observations prompted experiments with sAPP-derived peptides known to stimulate the growth of APP-deficient fibroblasts. Using autoradiography and radiochemical assays, we observed that an iodinated 19-mer sAPP peptide was bound specifically to the surface of FRTL-5 cells. Binding of this peptide was followed by a 2- to 8-fold increase in cell proliferation, which reached a plateau at 1 nM. This effect was significant only when cells were cultured in nonconfluent monolayers, and contact inhibition did not interfere. Our observations indicate that sAPP and sAPP-derived peptides increased the proportion of proliferation-competent FRTL-5 cells and suggest that sAPP may be a new member in the family of peptides involved in the growth regulation of thyrocytes. PMID:8612538

  18. Relationship of serum bilirubin concentration to kidney function and 24-hour urine protein in Korean adults

    Directory of Open Access Journals (Sweden)

    Jung Yeon Soon

    2011-06-01

    Full Text Available Abstract Background The relationships among serum bilirubin concentration, kidney function and proteinuria have yet to be fully elucidated, nor have these relationships been investigated in Korean adults. Method We retrospectively reviewed the medical records of Korean adults who were evaluated at Kosin University Gospel Hospital (Busan, Republic of Korea during a five-year period from January 2005 to December 2009. We evaluated the relationships among serum bilirubin concentration, estimated glomerular filtration rate (eGFR and 24-hour urinary protein excretion in a sample of 1363 Korean adults aged 18 years or older. Results The values of eGFR 2 and 24-hour urine albumin ?150 mg/day were observed in 26.1% (n = 356 and 40.5% (n = 553 of subjects, respectively. Fasting glucose levels ?126 mg/dL were observed in 44.9% (n = 612 of the total sample. After adjustment for potential confounding factors including demographic characteristics, comorbidities and other laboratory measures, total serum bilirubin was positively associated with eGFR and negatively associated with proteinuria both in the whole cohort and in a subgroup of diabetic individuals. Conclusions To our knowledge, this is the first hospital-based study specifically aimed at examining the relationships among serum total bilirubin concentration, 24-hour urine protein and kidney function in Korean adults. We demonstrated that serum total bilirubin concentration was negatively correlated with 24-hour urine protein and positively correlated with eGFR in Korean non-diabetic and diabetic adults.

  19. Nanomechanical properties of single amyloid fibrils.

    Science.gov (United States)

    Sweers, K K M; Bennink, M L; Subramaniam, V

    2012-06-20

    Amyloid fibrils are traditionally associated with neurodegenerative diseases like Alzheimer's disease, Parkinson's disease or Creutzfeldt-Jakob disease. However, the ability to form amyloid fibrils appears to be a more generic property of proteins. While disease-related, or pathological, amyloid fibrils are relevant for understanding the pathology and course of the disease, functional amyloids are involved, for example, in the exceptionally strong adhesive properties of natural adhesives. Amyloid fibrils are thus becoming increasingly interesting as versatile nanobiomaterials for applications in biotechnology. In the last decade a number of studies have reported on the intriguing mechanical characteristics of amyloid fibrils. In most of these studies atomic force microscopy (AFM) and atomic force spectroscopy play a central role. AFM techniques make it possible to probe, at nanometer length scales, and with exquisite control over the applied forces, biological samples in different environmental conditions. In this review we describe the different AFM techniques used for probing mechanical properties of single amyloid fibrils on the nanoscale. An overview is given of the existing mechanical studies on amyloid. We discuss the difficulties encountered with respect to the small fibril sizes and polymorphic behavior of amyloid fibrils. In particular, the different conformational packing of monomers within the fibrils leads to a heterogeneity in mechanical properties. We conclude with a brief outlook on how our knowledge of these mechanical properties of the amyloid fibrils can be exploited in the construction of nanomaterials from amyloid fibrils. PMID:22585542

  20. Nanomechanical properties of single amyloid fibrils

    International Nuclear Information System (INIS)

    Amyloid fibrils are traditionally associated with neurodegenerative diseases like Alzheimer’s disease, Parkinson’s disease or Creutzfeldt-Jakob disease. However, the ability to form amyloid fibrils appears to be a more generic property of proteins. While disease-related, or pathological, amyloid fibrils are relevant for understanding the pathology and course of the disease, functional amyloids are involved, for example, in the exceptionally strong adhesive properties of natural adhesives. Amyloid fibrils are thus becoming increasingly interesting as versatile nanobiomaterials for applications in biotechnology. In the last decade a number of studies have reported on the intriguing mechanical characteristics of amyloid fibrils. In most of these studies atomic force microscopy (AFM) and atomic force spectroscopy play a central role. AFM techniques make it possible to probe, at nanometer length scales, and with exquisite control over the applied forces, biological samples in different environmental conditions. In this review we describe the different AFM techniques used for probing mechanical properties of single amyloid fibrils on the nanoscale. An overview is given of the existing mechanical studies on amyloid. We discuss the difficulties encountered with respect to the small fibril sizes and polymorphic behavior of amyloid fibrils. In particular, the different conformational packing of monomers within the fibrils leads to a heterogeneity in mechanical properties. We conclude with a brief outlook on how our knowledge of these mechanical properties of the amyloid fibrils can be exploited in the construction of nanomaterials from amyloid fibrils. (topical review)

  1. The relationship of amyloid plaques to cerebral capillaries in Alzheimer's disease.

    OpenAIRE

    Kawai, M; Kalaria, R.N.; Harik, S. I.; Perry, G.

    1990-01-01

    The authors examined the hypothesis that senile plaques of Alzheimer's disease (AD) are formed by abnormal leakage of amyloidogenic precursors from brain capillaries by quantitative analysis of the spatial relationship between capillaries and amyloid plaques. Vibratome sections (40 mu) of the hippocampus, including the entorhinal cortex, obtained at autopsy from AD subjects, were immunostained with a monoclonal antibody to beta-protein and counterstained with rabbit serum to either the glucos...

  2. FE65 and FE65L1 amyloid precursor protein-binding protein compound null mice display adult-onset cataract and muscle weakness.

    Science.gov (United States)

    Suh, Jaehong; Moncaster, Juliet A; Wang, Lirong; Hafeez, Imran; Herz, Joachim; Tanzi, Rudolph E; Goldstein, Lee E; Guénette, Suzanne Y

    2015-06-01

    FE65 and FE65L1 are cytoplasmic adaptor proteins that bind a variety of proteins, including the amyloid precursor protein, and that mediate the assembly of multimolecular complexes. We previously reported that FE65/FE65L1 double knockout (DKO) mice display disorganized laminin in meningeal fibroblasts and a cobblestone lissencephaly-like phenotype in the developing cortex. Here, we examined whether loss of FE65 and FE65L1 causes ocular and muscular deficits, 2 phenotypes that frequently accompany cobblestone lissencephaly. Eyes of FE65/FE65L1 DKO mice develop normally, but lens degeneration becomes apparent in young adult mice. Abnormal lens epithelial cell migration, widespread small vacuole formation, and increased laminin expression underneath lens capsules suggest impaired interaction between epithelial cells and capsular extracellular matrix in DKO lenses. Cortical cataracts develop in FE65L1 knockout (KO) mice aged 16 months or more but are absent in wild-type or FE65 KO mice. FE65 family KO mice show attenuated grip strength, and the nuclei of DKO muscle cells frequently locate in the middle of muscle fibers. These findings reveal that FE65 and FE65L1 are essential for the maintenance of lens transparency, and their loss produce phenotypes in brain, eye, and muscle that are comparable to the clinical features of congenital muscular dystrophies in humans. PMID:25757569

  3. Mint2/X11-like colocalizes with the Alzheimer's disease amyloid precursor protein and is associated with neuritic plaques in Alzheimer's disease.

    OpenAIRE

    McLoughlin, DM; Irving, NG; Brownlees, J; Brion, JP; Leroy, K.; Miller, CC

    1999-01-01

    Aberrant metabolism of the amyloid precursor protein (APP) is believed to be at least part of the pathogenic process in Alzheimer's disease. The carboxy-terminus of APP has been shown to interact with the Mint/X11 family of phosphotyrosine binding (PTB) domain-bearing proteins. It is via their PTB domains that the Mints/X11s bind to APP. Here we report the cloning of full-length mouse Mint2 and demonstrate that in primary cortical neurons, Mint2 and APP share highly similar distributions. Min...

  4. Serum Adenosine deaminase activity and C-reactive protein levels in unstable angina

    Directory of Open Access Journals (Sweden)

    Rani Surekha

    2003-01-01

    Full Text Available In unstable angina (USA patients, immunological responses contributing to inflammation play a vital role in plaque rupture and thrombosis causing stroke. In the present study an attempt is made to estimate the levels of adenosine deaminase activity, an immunoenzyme marker and C-reactive protein, a marker of inflammation in USA patients. 45 patients presenting USA and 50 age and sex matched healthy controls were included in the study. Serum ADA activity was measured spectrophotometrically at 630nm and serum C-reactive protein was detected using Avitex CRP kit, which is a rapid latex agglutination test. The Mean ADA levels were 41.15 ± 11.04 in patients and 20.71±5.63 in controls and 66.6% of patients and none of the controls were positive to CRP. The present study observed the importance of ADA as a serum marker in addition to CRP for assessing the immune response in USA patients.

  5. Genetic factors explain half of all variance in serum eosinophil cationic protein

    DEFF Research Database (Denmark)

    Elmose, C.; Sverrild, A.

    2014-01-01

    BackgroundEosinophil cationic protein (ECP) is one of four basic proteins of the secretory granules of eosinophils. It has a variety of functions associated with inflammatory responses. Little is known about the causes for variation in serum ECP levels. AimTo identify factors associated with variation in serum ECP and to determine the relative proportion of the variation in ECP due to genetic and non-genetic factors, in an adult twin sample. MethodsA sample of 575 twins, selected through a proband with self-reported asthma, had serum ECP, lung function, airway responsiveness to methacholine, exhaled nitric oxide, and skin test reactivity, measured. Linear regression analysis and variance component models were used to study factors associated with variation in ECP and the relative genetic influence on ECP levels. ResultsSex (regression coefficient=-0.107, P

  6. Hybrid selection of messenger ribonucleoprotein for serum albumin: analysis of specific message-bound proteins.

    OpenAIRE

    Johnson, T. R.; Ilan, J

    1985-01-01

    The messenger RNA for chicken serum albumin together with its specific binding proteins was purified by hybrid selection using filter-bound cloned albumin cDNA. Under conditions where hybridization of the protein-mRNA complex was specific for the immobilized cDNA sequence, no dissociation of the complex into its protein and RNA components was apparent. Electrophoretic analysis of albumin mRNA-specific binding proteins showed three major bands. Two of these were prominent in total poly(A) mess...

  7. Revision of the biodistribution of uranyl in serum: is fetuin-A the major protein target?

    Science.gov (United States)

    Basset, Christian; Averseng, Olivier; Ferron, Pierre-Jean; Richaud, Nicolas; Hagège, Agnès; Pible, Olivier; Vidaud, Claude

    2013-05-20

    Uranium is a natural actinide present as uranyl U(VI) species in aqueous environments. Its toxicity is considered to be chemical rather than radiotoxicological. Whatever the route of entry, uranyl reaches the blood, is partly eliminated via the kidneys, and accumulated in the bones. In serum, its speciation mainly involves carbonate and proteins. Direct identification of labile uranyl-protein complexes is extremely difficult because of the complexity of this matrix. Thus, until now the biodistribution of the metal in serum has not been described, and therefore, little is known about the metal transport mechanisms leading to bone accumulation. A rapid screening method based on a surface plasmon resonance (SPR) technique was used to determine the apparent affinities for U(VI) of the major serum proteins. A first biodistribution of uranyl was obtained by ranking the proteins according to the criteria of both their serum concentrations and affinities for this metal. Despite its moderate concentration in serum, fetuin-A (FETUA) was shown to exhibit an apparent affinity within the 30 nM range and to carry more than 80% of the metal. This protein involved in bone mineralization aroused interest in characterizing the U(VI) and FETUA interaction. Using complementary chromatographic and spectroscopic approaches, we demonstrated that the protein can bind 3 U(VI) at different binding sites exhibiting Kd from ?30 nM to 10 ?M. Some structural modifications and functional properties of FETUA upon uranyl complexation were also controlled. To our knowledge, this article presents the first identification of a uranyl carrier involved in bone metabolism along with the characterization of its metal binding sites. PMID:23527557

  8. Serum Bone Morphogenic Protein-4 Contributes to Discriminating Coronary Artery Disease Severity

    Science.gov (United States)

    Park, Chul Soo; Hong, Oak-Kee; Kim, Mee Kyoung; Chung, Woo Baek; Choi, Yun Seok; Baek, Ki-Hyun; Song, Ki-Ho; Lee, Man Young; Kwon, Hyuk-Sang

    2015-01-01

    Abstract Bone morphogenic protein 4 (BMP-4) is a known pro-inflammatory and pro-atherogenic cytokine. Here, we investigated whether the serum BMP-4 level predicts coronary artery disease (CAD) severity in humans. We measured serum BMP-4 concentrations in 1044 consecutive patients who underwent elective coronary angiography and percutaneous coronary intervention. CAD severity was estimated by the number of diseased vessels showing ?50% diameter stenosis. Among males, the serum BMP-4 level was significantly lower in patients with multivessel disease (MVD) compared with those with single-vessel disease (SVD) (16.3?±?22.6 vs. 22.0?±?28.4?pg/mL, P?serum BMP-4 level was an independent predictor for a decreased risk of MVD (odds ratio, 0.992; 95% confidence interval [CI], 0.985–0.998; P?=?0.01) and patients in the lower tertile were 1.55-fold more likely to have MVD compared with upper tertile patients. Receiver-operating characteristic curve analysis demonstrated that the serum BMP-4 level had a 54% sensitivity and 54% specificity for predicting MVD (area under the curve [AUC], 56.5%; 95% CI, 51.9–61.0%; P?Serum BMP-4 improved the predictive capability of risk factors for MVD (AUC with and without BMP-4: 64.9 and 63.6%, respectively). Considering the likelihood ratio and number of parameters, adding the serum BMP-4 level provided a better-fit model for predicting MVD compared with the model consisting of conventional risk factors (likelihood ratio ?2?=?6.20, P?=?0.01). However, an association between serum BMP-4 and CAD was not observed in females. Serum BMP-4 levels are independently associated with CAD severity and contribute to discriminating CAD severity in males. PMID:26426615

  9. Differentially Expressed RNA from Public Microarray Data Identifies Serum Protein Biomarkers for Cross-Organ Transplant Rejection and Other Conditions

    OpenAIRE

    Chen, Rong; Sigdel, Tara K.; LI Li; Kambham, Neeraja; DUDLEY, JOEL T.; Hsieh, Szu-chuan; Klassen, R. Bryan; Chen, Amery; Caohuu, Tuyen; Morgan, Alexander A.; Valantine, Hannah A; Khush, Kiran K.; Sarwal, Minnie M.; Butte, Atul J

    2010-01-01

    Serum proteins are routinely used to diagnose diseases, but are hard to find due to low sensitivity in screening the serum proteome. Public repositories of microarray data, such as the Gene Expression Omnibus (GEO), contain RNA expression profiles for more than 16,000 biological conditions, covering more than 30% of United States mortality. We hypothesized that genes coding for serum- and urine-detectable proteins, and showing differential expression of RNA in disease-damaged tissues would ma...

  10. High-protein diets in hyperlipidemia : effect of wheat gluten on serum lipids, uric acid, and renal function

    OpenAIRE

    Jenkins, D. J. A.; Kendall, C.W.C.; Vidgen, E.; Augustin, L.S.A.; Erk, M., van; Van Geelen, A.; Parker, T.; Faulkner, D.; Vuksan, V; Josse, R.G.; Leiter, L. A.; Connelly, P.W.

    2001-01-01

    BACKGROUND: The metabolic effects of diets high in vegetable protein have not been assessed despite much recent interest in the effect of soy proteins in reducing serum cholesterol. OBJECTIVE: We assessed the metabolic effects of diets high in vegetable protein (specifically, wheat gluten) on serum lipids, uric acid concentrations, and renal function. DESIGN: Twenty hyperlipidemic men and women consumed isoenergetic test (high-protein) and control metabolic diets for 1 mo in a randomized cros...

  11. Identification of the major mannose-binding proteins from chicken egg yolk and chicken serum as immunoglobulins.

    OpenAIRE

    Wang, K. Y.; Hoppe, C A; Datta, P. K.; Fogelstrom, A; Y. C. Lee

    1986-01-01

    Chicken egg yolk contains a mannose-binding protein that could be purified with a modification of the procedure of affinity chromatography and gel filtration used for chicken serum mannose-binding protein. The yolk protein was indistinguishable from the serum protein with respect to apparent molecular masses (169 +/- 7 kDa), subunits (74 kDa and 27 kDa, in approximately 1:1 ratio) produced after denaturation in the presence of mercaptoethanol, immunoreactivity with antibody against the chicke...

  12. A preliminary study on the serum protein response in canine babesiosis : research communication

    OpenAIRE

    R. G. Lobetti; A.J. Möhr; T. Dippenaar; Myburgh, E.

    2012-01-01

    Total serum protein, albumin, globulin, globulin fractions (alpha, beta and gamma globulins) and an acute-phase protein ((alpha)1-acid glycoprotein) were evaluated in dogs with naturally occurring mild (Group 1), severe (Group 2) or complicated babesiosis (Group 3). Results showed that the total serumprotein, albumin, A/G ratio and (alpha)globulins were statistically different between Groups 1 and 2. There was no statistical difference between groups with total, (beta)and (gamma) globulins. T...

  13. Proteomic approach to investigate alterations, within physiological limits, in serum protein of sea bass (Dicentrarchus labrax)

    OpenAIRE

    Coeurdacier, Jean-luc

    2010-01-01

    In previous experiments reared fish were submitted to six stressful situations. The potential negative impact on their life was investigated using 9 water parameters and 19 fish parameters including global serum protein. Proteinemia allows to follow important stress situation but it cannot be used to detect small variations within physiological limits +like stocking density. For stocking density proteinemia is at the limit of its discriminating power. Studies of protein panel modification in ...

  14. Studies on the effect of Fenchlorphos on postirradiation changes of serum proteins and nucleic acids content in rat liver

    International Nuclear Information System (INIS)

    The effects of Fenchlorphos on postirradiation changes of serum protein levels and nucleic acid content in rat liver were investigated. It was found that this compound significantly decreases postirradiation changes in serum proteins, properdin level and nucleic acid content in rat liver. An important role of these phenomena in radioprotective action of Fenchlorphos is suggested. (orig.)

  15. Steigerung der Bildung des ß-Amyloid Peptids durch Protein-vermittelte Genese Cholesterin-reicher Membrandomänen

    OpenAIRE

    Matthiesen, Sabine

    2009-01-01

    Obwohl seit der erstmaligen Beschreibung der Alzheimer-Erkrankung vor über 100 Jahren eine Vielzahl der ursächlichen histopathologischen Veränderungen und der beteiligten molekularen Mechanismen erforscht werden konnte, ist noch unklar, welche Faktoren die Spaltung des ß-Amyloid Vorläuferproteins (APP) beeinflussen und zu der pathologischen ß-Amyloid (Aß) Bildung und Aggregation führen. In zahlreichen Studien ergaben sich Hinweise, dass Cholesterin einen wichtigen Modulator der Alzheimer-Erkr...

  16. PuF, an antimetastatic and developmental signaling protein, interacts with the Alzheimer’s amyloid-? precursor protein via a tissue-specific proximal regulatory element (PRE

    Directory of Open Access Journals (Sweden)

    Lahiri Debomoy K

    2013-01-01

    Full Text Available Abstract Background Alzheimer’s disease (AD is intimately tied to amyloid-? (A? peptide. Extraneuronal brain plaques consisting primarily of A? aggregates are a hallmark of AD. Intraneuronal A? subunits are strongly implicated in disease progression. Protein sequence mutations of the A? precursor protein (APP account for a small proportion of AD cases, suggesting that regulation of the associated gene (APP may play a more important role in AD etiology. The APP promoter possesses a novel 30 nucleotide sequence, or “proximal regulatory element” (PRE, at ?76/?47, from the +1 transcription start site that confers cell type specificity. This PRE contains sequences that make it vulnerable to epigenetic modification and may present a viable target for drug studies. We examined PRE-nuclear protein interaction by gel electrophoretic mobility shift assay (EMSA and PRE mutant EMSA. This was followed by functional studies of PRE mutant/reporter gene fusion clones. Results EMSA probed with the PRE showed DNA-protein interaction in multiple nuclear extracts and in human brain tissue nuclear extract in a tissue-type specific manner. We identified transcription factors that are likely to bind the PRE, using competition gel shift and gel supershift: Activator protein 2 (AP2, nm23 nucleoside diphosphate kinase/metastatic inhibitory protein (PuF, and specificity protein 1 (SP1. These sites crossed a known single nucleotide polymorphism (SNP. EMSA with PRE mutants and promoter/reporter clone transfection analysis further implicated PuF in cells and extracts. Functional assays of mutant/reporter clone transfections were evaluated by ELISA of reporter protein levels. EMSA and ELISA results correlated by meta-analysis. Conclusions We propose that PuF may regulate the APP gene promoter and that AD risk may be increased by interference with PuF regulation at the PRE. PuF is targeted by calcium/calmodulin-dependent protein kinase II inhibitor 1, which also interacts with the integrins. These proteins are connected to vital cellular and neurological functions. In addition, the transcription factor PuF is a known inhibitor of metastasis and regulates cell growth during development. Given that APP is a known cell adhesion protein and ferroxidase, this suggests biochemical links among cell signaling, the cell cycle, iron metabolism in cancer, and AD in the context of overall aging.

  17. A Nanobody Binding to Non-Amyloidogenic Regions of the Protein Human Lysozyme Enhances Partial Unfolding but Inhibits Amyloid Fibril Formation

    Science.gov (United States)

    Pardon, Els; Hsu, Shang-Te D.; Kumita, Janet R.; Christodoulou, John; Menzer, Linda; Chirgadze, Dimitri Y.; Robinson, Carol V.; Muyldermans, Serge; Matagne, André; Wyns, Lode; Dobson, Christopher M.; Dumoulin, Mireille

    2015-01-01

    We report the effects of the interaction of two camelid antibody fragments, generally called nanobodies, namely cAb-HuL5 and a stabilized and more aggregation-resistant variant cAb-HuL5G obtained by protein engineering, on the properties of two amyloidogenic variants of human lysozyme, I56T and D67H, whose deposition in vital organs including the liver, kidney, and spleen is associated with a familial non-neuropathic systemic amyloidosis. Both NMR spectroscopy and X-ray crystallographic studies reveal that cAb-HuL5 binds to the ?-domain, one of the two lobes of the native lysozyme structure. The binding of cAb-HuL5/cAb-HuL5G strongly inhibits fibril formation by the amyloidogenic variants; it does not, however, suppress the locally transient cooperative unfolding transitions, characteristic of these variants, in which the ?-domain and the C-helix unfold and which represents key early intermediate species in the formation of amyloid fibrils. Therefore, unlike two other nanobodies previously described, cAb-HuL5/cAb-HuL5G does not inhibit fibril formation via the restoration of the global cooperativity of the native structure of the lysozyme variants to that characteristic of the wild-type protein. Instead, it inhibits a subsequent step in the assembly of the fibrils, involving the unfolding and structural reorganization of the ?-domain. These results show that nanobodies can protect against the formation of pathogenic aggregates at different stages in the structural transition of a protein from the soluble native state into amyloid fibrils, illustrating their value as structural probes to study the molecular mechanisms of amyloid fibril formation. Combined with their amenability to protein engineering techniques to improve their stability and solubility, these findings support the suggestion that nanobodies can potentially be developed as therapeutics to combat protein misfolding diseases. PMID:23919586

  18. Ratio of serum tartrate-inhibitable acid phosphatase to total serum protein in benign prostatic hypertrophy and prostatic carcinoma.

    Science.gov (United States)

    Petrovich, G; Ursich-Jankovich, J; Prijovich, Z

    1992-02-01

    The activity concentration and the specific activity (the ratio of enzyme activity to total serum protein) of the tartrate-inhibitable fraction of acid phosphatase [orthophosphoric monoester phosphohydrolase (acid optimum), EC 3.1.3.2; TIAP] were related to benign prostatic hypertrophy and to prostatic carcinoma. As expected, the TIAP activity concentrations assayed in the sera of patients with benign prostatic hypertrophy were within the range of those assayed in normal human sera. In contrast, the specific activities of TIAP determined in the sera of patients with benign prostatic hypertrophy were significantly higher than those determined in the control group. In the sera of prostatic carcinoma patients, both the TIAP activity concentrations and the TIAP specific activities differed significantly (F = 730) from the normal values. PMID:1371723

  19. Protein aggregation containing beta-amyloid, alpha-synuclein and hyperphosphorylated tau in cultured cells of hippocampus, substantia nigra and locus coeruleus after rotenone exposure

    Directory of Open Access Journals (Sweden)

    Martins Stephanie A

    2010-11-01

    Full Text Available Abstract Background Protein aggregates containing alpha-synuclein, beta-amyloid and hyperphosphorylated tau are commonly found during neurodegenerative processes which is often accompanied by the impairment of mitochondrial complex I respiratory chain and dysfunction of cellular systems of protein degradation. In view of this, we aimed to develop an in vitro model to study protein aggregation associated to neurodegenerative diseases using cultured cells from hippocampus, locus coeruleus and substantia nigra of newborn Lewis rats exposed to 0.5, 1, 10 and 25 nM of rotenone, which is an agricultural pesticide, for 48 hours. Results We demonstrated that the proportion of cells in culture is approximately the same as found in the brain nuclei they were extracted from. Rotenone at 0.5 nM was able to induce alpha-synuclein and beta amyloid aggregation, as well as increased hyperphosphorylation of tau, although high concentrations of this pesticide (over 1 nM lead cells to death before protein aggregation. We also demonstrated that the 14kDa isoform of alpha-synuclein is not present in newborn Lewis rats. Conclusion Rotenone exposure may lead to constitutive protein aggregation in vitro, which may be of relevance to study the mechanisms involved in idiopathic neurodegeneration.

  20. Rapid tyrosine phosphorylation of neuronal proteins including tau and focal adhesion kinase in response to amyloid-beta peptide exposure: involvement of Src family protein kinases.

    Science.gov (United States)

    Williamson, Ritchie; Scales, Timothy; Clark, Bruce R; Gibb, Graham; Reynolds, C Hugh; Kellie, Stuart; Bird, Ian N; Varndell, Ian M; Sheppard, Paul W; Everall, Ian; Anderton, Brian H

    2002-01-01

    The increased production of amyloid beta-peptide (Abeta) in Alzheimer's disease is acknowledged to be a key pathogenic event. In this study, we examined the response of primary human and rat brain cortical cultures to Abeta administration and found a marked increase in the tyrosine phosphorylation content of numerous neuronal proteins, including tau and putative microtubule-associated protein 2c (MAP2c). We also found that paired helical filaments of aggregated and hyperphosphorylated tau are tyrosine phosphorylated, indicating that changes in the phosphotyrosine content of cytoplasmic proteins in response to Abeta are potentially an important process. Increased tyrosine phosphorylation of cytoskeletal and other neuronal proteins was specific to fibrillar Abeta(25-35) and Abeta(1-42). The tyrosine phosphorylation was blocked by addition of the Src family tyrosine kinase inhibitor 4-amino-5-(4-chlorophenyl)-7(t-butyl)pyrazol(3,4-d)pyramide (PP2) and the phosphatidylinositol 3-kinase inhibitor LY 294002. Tyrosine phosphorylation of tau and MAP2c was concomitant with an increase in the tyrosine phosphorylation and subsequent putative activation of the non-receptor kinase, focal adhesion kinase (FAK). Immunoprecipitation of Fyn, a member of the Src family, from Abeta(25-35)-treated neurons showed an increased association of Fyn with FAK. Abeta treatment of cells also stimulated the sustained activation of extracellular regulated kinase-2, which was blocked by addition of PP2 and LY 294002, suggesting that FAK/Fyn/PI3-kinase association is upstream of mitogen-activated protein (MAP) kinase signaling in Abeta-treated neurons. This cascade of signaling events contains the earliest biochemical changes in neurons to be described in response to Abeta exposure and may be critical for subsequent neurodegenerative changes. PMID:11756483

  1. Clinical significance of serum sex hormones protein and lipid determination in patients with ulcerative colitis

    International Nuclear Information System (INIS)

    Objective: To investigate the relationships between changes of serum sex hormones levels and protein-lipid metabolism in patients with ulcerative colitis. Methods: Serum levels of estradiol (E2) pregnenedione (P), prolactin(PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH) (with CLIA), sree testos (T, with RIA) and total-protein (TP), albumin (Alb), globulin (G), albumin/globulinratio (A/G) total-cholesterd (TC), high density lipoprotein cholesterols (LDL-C) (with biochemistry were determined in 72 patients) with ulcerative colitis and 72 controls. Results: The serum levels of T, LH, FSH, TP, Alb, A/G, TC, LDL-C in patients with ulcerative colitis were significantly lower than those in controls (P2, PRL in patients with ulcerative colitis were significantly higher than those in controls (P2 were negatively correlated with TP, A/G and TC (P2 levels in the female sex (P>0.05) as well as between LH, FSH and T levels in the male sex (P>0.05). Conclusion: The abnormal serum levels of sex hormone might contribute to the development of hypoproteinaemia and lowered lipid levels in patients with ulcerative colitis. Treatment with correction of serum sex hormones levels might be beneficial to the patients. (authors)

  2. Comprehensive characterisation of pulmonary and serum surfactant protein D in COPD

    Directory of Open Access Journals (Sweden)

    Erpenbeck Veit J

    2011-03-01

    Full Text Available Abstract Background Pulmonary surfactant protein D (SP-D is considered as a candidate biomarker for the functional integrity of the lung and for disease progression, which can be detected in serum. The origin of SP-D in serum and how serum concentrations are related to pulmonary concentrations under inflammatory conditions is still unclear. Methods In a cross-sectional study comprising non-smokers (n = 10, young - (n = 10, elderly smokers (n = 20, and smokers with COPD (n = 20 we simultaneously analysed pulmonary and serum SP-D levels with regard to pulmonary function, exercise, repeatability and its quaternary structure by native gel electrophoresis. Statistical comparisons were conducted by ANOVA and post-hoc testing for multiple comparisons; repeatability was assessed by Bland-Altman analysis. Results In COPD, median (IQR pulmonary SP-D levels were lower (129(68 ng/ml compared to smokers (young: 299(190, elderly: 296(158 ng/ml; p Conclusions Pulmonary and serum SP-D levels are stable markers influenced by smoking and related to airflow obstruction and disease state. Smaller subunits of pulmonary SP-D and the rapid increase of serum SP-D levels in COPD due to exercise support the translocation hypothesis and its use as a COPD biomarker. Trial registration no interventional trial

  3. In vitro binding study of gemfibrozil to human serum proteins and erythrocytes: interactions with other drugs.

    Science.gov (United States)

    Hamberger, C; Barre, J; Zini, R; Taiclet, A; Houin, G; Tillement, J P

    1986-01-01

    The binding of gemfibrozil to human serum, isolated proteins and erythrocytes was studied in vitro by equilibrium dialysis. Our results show that this drug is highly bound to serum (99%) at therapeutic levels. Human serum albumin was shown to be mainly responsible for this binding (98.6%) with a saturable process characterized by two binding sites with a moderate affinity. Like many acidic drugs with a carboxylic acidic group, gemfibrozil showed none or negligible binding to alpha 1 acid glycoprotein, lipoproteins and gamma-globulins. The drug binding to erythrocytes is very low (0.8%). The unbound fraction in blood remains constant (0.8%) within the range of therapeutic concentrations. Moreover, interactions were studied with bilirubin and palmitic acid at pathophysiological concentrations and acenocoumarol, salicylic acid, valproic acid, furosemide, phenylbutazone, tolbutamide, warfarin and sulfamethoxazol at therapeutic concentrations. Neither endogenous compounds nor the other drugs studied altered gemfibrozil binding in serum. Likewise, the binding of warfarin to serum and to human serum albumin (600 microM) is not influenced by gemfibrozil. PMID:3468088

  4. Evaluation of full-length, cleaved and nitrosylated serum surfactant protein D as biomarkers for COPD

    DEFF Research Database (Denmark)

    Duvoix, Annelyse; Miranda, Elena

    2011-01-01

    Chronic obstructive pulmonary disease (COPD) is a multicomponent condition that is characterized by partially reversible airflow obstruction. Serum surfactant protein D (SP-D) is synthesized by type II pneumocytes and Clara cells and participates in surfactant homeostasis and pulmonary host defense. Serum levels of SP-D are raised in individuals with COPD but there is no correlation between the serum level of SP-D and the severity of airflow obstruction. Serum SP-D is present in different forms that may have more utility as a biomarker for COPD. We report here the development of new monoclonal antibodies to full length and cleaved SP-D. We have assessed these and existing antibodies in 98 individuals with COPD recruited to the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) cohort. Our data show that neither monoclonal antibodies to full length nor cleaved SP-D provide additional information over that obtained with a polyclonal antibody. Moreover, levels of serum nitrosylated-SP-D did not correlate with serum level of SP-D or any clinical phenotype of COPD. The measurement of modified SP-D is of limited value in characterising individuals with COPD.

  5. Ferritin L is the sole serum ferritin constituent and a positive hepatic acute-phase protein.

    Science.gov (United States)

    Naz, Naila; Moriconi, Federico; Ahmad, Shakil; Amanzada, Ahmad; Khan, Sajjad; Mihm, Sabine; Ramadori, Guiliano; Malik, Ihtzaz Ahmed

    2013-06-01

    Ferritin L (FTL) and ferritin H (FTH) subunits are responsible for intracellular iron storage. Serum ferritin levels are not only dependant on body iron stores. Aims of the present study are to demonstrate nature, source, and major regulatory mediators of serum ferritin in an animal model of acute-phase (AP) response. Animals (rats, wild-type [WT] mice, and interleukin [IL]-6ko mice) were injected with turpentine oil (TO) intra-muscularity to induce a sterile abscess and sacrificed at different time points afterward. Rat hepatocytes were isolated for cell culture and, after reaching confluence, stimulated with major AP cytokines to induce AP conditions. We found a significantly increased expression of both ferritin subunits in liver at mRNA and protein levels during AP response. In the serum of both control and TO-injected rats, only FTL was detectable by Western blotting, whereas no increase in serum FTL was measured by Western blot or enzyme-linked immunosorbent assay. An increase in protein expression of FTL and FTH was observed in lysates of rat hepatocytes after treatment with IL-6, IL-1?, and tumor necrosis factor-?; however, only FTL was increasingly released into supernatant. In both TO-injected rats and WT mice, a dramatic increase in serum IL-6 levels was observed, along with an increased amount of hepatic ferritin subunits. However, an increase of hepatic FTL but not of FTH protein expression was observed in IL-6ko mice after TO injection. Our data demonstrate that FTL is the only rat serum ferritin whose release into circulation from the hepatocytes is increased by the effect of AP cytokines (e.g., IL-6). In contrast, FTH expression is intracellular in both under physiological and AP conditions. PMID:23524846

  6. Presence of non-fibrillar amyloid beta protein in skin biopsies of Alzheimer's disease (AD), Down's syndrome and non-AD normal persons

    DEFF Research Database (Denmark)

    Wen, G Y; Wisniewski, H M

    1994-01-01

    A total of 66 skin biopsies from persons with Alzheimer's disease (AD) or Down's syndrome (DS) and from persons without AD were used in this study. The age range was from 7 to 89 years. Positive immunoreactivity of skin biopsies to monoclonal antibody 4G8, which is reactive to amino acid residue 17-24 of synthetic amyloid beta protein (A beta), and 4G8-Fab (the antigen-binding fragment of 4G8 IgG, reactive only to amyloid plaque) was observed in the epidermis-dermis junction or the basement membrane of the epidermis and in some blood vessels of the biopsy skins of 13/18 (72%) AD, 9/10 (90%) DS, and 14/38 (37%) non-AD control cases. The Fisher exact probability test revealed a significant difference (P = 0.0415 one-tailed) in immunoreactivity between AD and age-matched controls. There was also a significant difference (P = 0.0152 one-tailed; P = 0.0200 two-tailed) between DS and age-matched control in the same test. Immuno-gold electron microscopy examination of these cases with positive immunoreactivity revealed that the gold particles were deposited along the basement membrane of the epidermis. Amyloid fibrils were not observed in the regions with gold particles. Results of this study suggest that A beta is associated with the basement membrane of skin and is present in amorphous, non-fibrillar form as soluble A beta.

  7. The OspE-Related Proteins Inhibit Complement Deposition and Enhance Serum Resistance of Borrelia burgdorferi, the Lyme Disease Spirochete ?

    OpenAIRE

    Kenedy, Melisha R; Akins, Darrin R

    2011-01-01

    Borrelia burgdorferi, the Lyme disease spirochete, binds the host complement inhibitors factor H (FH) and FH-like protein 1 (FHL-1). Binding of FH/FHL-1 by the B. burgdorferi proteins CspA and the OspE-related proteins is thought to enhance resistance to serum-mediated killing. While previous reports have shown that CspA confers serum resistance in B. burgdorferi, it is unclear whether the OspE-related proteins are relevant in B. burgdorferi serum resistance when OspE is expressed on the borr...

  8. Serum-dependent expression of promyelocytic leukemia protein suppresses propagation of influenza virus

    International Nuclear Information System (INIS)

    The rate of propagation of influenza virus in human adenocarcinoma Caco-2 cells was found to negatively correlate with the concentration of fetal bovine serum (FBS) in the culture medium. Virus replicated more rapidly at lower FBS concentrations (0 or 2%) than at higher concentrations (10 or 20%) during an early stage of infection. Basal and interferon (IFN)-induced levels of typical IFN-inducible anti-viral proteins, such as 2',5'-oligoadenylate synthetase, dsRNA-activated protein kinase and MxA, were unaffected by variation in FBS concentrations. But promyelocytic leukemia protein (PML) was expressed in a serum-dependent manner. In particular, the 65 to 70 kDa isoform of PML was markedly upregulated following the addition of serum. In contrast, other isoforms were induced by IFN treatment, and weakly induced by FBS concentrations. Immunofluorescence microscopy indicated that PML was mainly formed nuclear bodies in Caco-2 cells at various FBS concentrations, and the levels of the PML-nuclear bodies were upregulated by FBS. Overexpression of PML isoform consisting of 560 or 633 amino acid residues by transfection of expression plasmid results in significantly delayed viral replication rate in Caco-2 cells. On the other hand, downregulation of PML expression by RNAi enhanced viral replication. These results indicate that PML isoforms which are expressed in a serum-dependent manner suppress the propagation of influenza virus at an early stage of infection

  9. Determination of serum thyroxine content by competitive protein binding and gel filtration

    International Nuclear Information System (INIS)

    A gel filtration tecnique based on competitive protein binding was improved for the determination of thyroxine in human serum. The principle of the assay is the competitive protein binding that is the thyroxine releases from protein binding competes the labelled compound. After the reaction with a known thyroxine binding globuline (TBG) the thyroxine content can be evaluated measuring the radioactivity. Modifications were aimed to substitute the expensive import materials. As a result serum from pregnants was suitable for TBG. The quantity of Sephadex gel can be reduced by regeneration. In the critical phases of gel filtration experiments were carried out for the optimization of elution. The confidence of the method was checked in the clinical practice. The values gained from euthyreoid, hyper- and hypothyreoid groups differed very distincly. (D.E.)

  10. Immune Reactivity of Brucella Melitensis–Vaccinated Rabbit Serum with Recombinant Omp31 and Dnak Proteins

    Directory of Open Access Journals (Sweden)

    Mahmood Jeddi-Tehrani

    2013-03-01

    Full Text Available Background and objectives: Brucella melitensis infection is still a major health problem for human and cattle in developing countries and the Middle East.Materials and Methods: In this study, in order to screen immunogenic candidate antigens for the development of a Brucella subunit vaccine, a cytoplasmic protein (DnaK and an outer membrane protein (Omp31 of B. melitensis were cloned, expressed in E.coli BL21 and then purified using Ni-NTA agarose. Immunized serum was prepared from a rabbit inoculated with attenuated B. melitensis.Results and Conclusion: It was proved that immunized serum contains antibodies against recombinant Omp31 (rOmp31 and DnaK (rDnaK by Western blot and ELISA assays. The results may suggest the importance of these proteins as subunit vaccines against B. melitensis as well as targets for immunotherapy.

  11. Detection of insulin-like growth factor binding proteins (IGFBPs) in porcine serum

    OpenAIRE

    Masnikosa Romana; Bari?evi? Ivona; Lagundžin Dragana; Nedi? Olgica

    2010-01-01

    Multiple insulin-like growth factor binding proteins (IGFBPs) are found in sera of various species. This study was conducted to investigate whether IGFBPs in porcine serum could be detected using antibodies and antisera raised against human IGFBP-1, -2, -3 and -4. Western ligand blot procedure was used for the identification of c in porcine serum. The results presented in this work showed that the heterologous antibodies can be used to identify IGFBP-1, IGFBP-2 and IGFBP-3, but not IGFBP-4 in...

  12. Correlation between Ocular Demodex Infestation and Serum Immunoreactivity to Bacillus Proteins in Patients with Facial Rosacea

    OpenAIRE

    Li, Jianjing; O'Reilly, Niamh; Sheha, Hosam; Katz, Raananah; Raju, Vadrevu K.; Kavanagh, Kevin; Scheffer, C. G. Tseng

    2010-01-01

    Purpose—To investigate correlation between ocular Demodex infestation and serum. Design—A prospective study to correlate clinical findings with laboratory data. Participants—We consecutively enrolled 59 patients: 34 men and 25 women with a mean age of 60.4±17.6 years (range, 17–93). Methods—Demodex counting was performed based on lash sampling. Serum immunoreactivity to two 62-kDa and 83-kDa proteins derived from B oleronius was determined by Western blot analysis. Facial ro...

  13. Amyloid ? accelerates phosphorylation of tau and neurofibrillary tangle formation in an amyloid precursor protein and tau double-transgenic mouse model.

    Science.gov (United States)

    Seino, Yusuke; Kawarabayashi, Takeshi; Wakasaya, Yasuhito; Watanabe, Mitsunori; Takamura, Ayumi; Yamamoto-Watanabe, Yukiko; Kurata, Tomoko; Abe, Koji; Ikeda, Masaki; Westaway, David; Murakami, Tetsuro; Hyslop, Peter St George; Matsubara, Etsuro; Shoji, Mikio

    2010-12-01

    In Alzheimer's disease, A? deposits are considered the initial cardinal events that induce tauopathy secondarily. However, the relationship between A? amyloidosis and tauopathy has not been determined in detail. We produced double transgenic mice, 2×TgTau(+/-) APP(+/-) , by mating Tg2576 mice that exhibit A? amyloidosis and TgTauP301L mice that show tauopathy, and statistically analyzed the effect of A? accumulation on tauopathy. There was no significant difference in theprogression of A? accumulation among 2×TgTau(+/-) APP(+/-) and 1×TgTau(-/-) APP(+/-) , and tau accumulation among 2×TgTau(+/-) APP(+/-) and 1×Tg Tau(+/-) APP(-/-) . The appearance rates of phosphorylated tau developing in neurons and processes were significantly accelerated in 2×TgTau(+/-) APP(+/-) mice compared with those in 1×TgTau(+/-) APP(-/-) mice at 23 months of age. Accumulation of phosphorylated and confomationally altered tau and GSK3? in neuronal processes was accelerated in the white matter in 2×TgTau(+/-) APP(+/-) . The level of phosphorylated tau in the sarkosyl-insoluble fraction was increased in 2×TgTau(+/-) APP(+/-) brains compared with that in 1×TgTau(+/-) APP(-/-) brains. Thus, A? amyloid partially enhances tauopathy through accumulation of insoluble, phosphorylated, and conformationally changed tau in neuronal cytoplasm and processes in the late stage. PMID:20936700

  14. Critical analysis of the use of ?-site amyloid precursor protein-cleaving enzyme 1 inhibitors in the treatment of Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Evin G

    2014-01-01

    Full Text Available Genevieve Evin,1,2 Adel Barakat21Oxidation Biology Laboratory, Mental Health Research Institute, Florey Institute of Neuroscience and Mental Health, University of Melbourne, 2Department of Pathology, University of Melbourne, Parkville, VIC, AustraliaAbstract: Alzheimer's disease (AD is the major cause of dementia in the elderly and an unmet clinical challenge. A variety of therapies that are currently under development are directed to the amyloid cascade. Indeed, the accumulation and toxicity of amyloid-? (A? is believed to play a central role in the etiology of the disease, and thus rational interventions are aimed at reducing the levels of A? in the brain. Targeting ?-site amyloid precursor protein-cleaving enzyme (BACE-1 represents an attractive strategy, as this enzyme catalyzes the initial and rate-limiting step in A? production. Observation of increased levels of BACE1 and enzymatic activity in the brain, cerebrospinal fluid, and platelets of patients with AD and mild cognitive impairment supports the potential benefits of BACE1 inhibition. Numerous potent inhibitors have been generated, and many of these have been proved to lower A? levels in the brain of animal models. Over 10 years of intensive research on BACE1 inhibitors has now culminated in advancing half a dozen of these drugs into human trials, yet translating the in vitro and cellular efficacy of BACE1 inhibitors into preclinical and clinical trials represents a challenge. This review addresses the promises and also the potential problems associated with BACE1 inhibitors for AD therapy, as the complex biological function of BACE1 in the brain is becoming unraveled.Keywords: amyloid, dementia, secretase, aspartyl protease, neuregulin

  15. PB1-F2 influenza A virus protein adopts a beta-sheet conformation and forms amyloid fibers in membrane environments.

    Science.gov (United States)

    Chevalier, Christophe; Al Bazzal, Ali; Vidic, Jasmina; Février, Vincent; Bourdieu, Christiane; Bouguyon, Edwige; Le Goffic, Ronan; Vautherot, Jean-François; Bernard, Julie; Moudjou, Mohammed; Noinville, Sylvie; Chich, Jean-François; Da Costa, Bruno; Rezaei, Human; Delmas, Bernard

    2010-04-23

    The influenza A virus PB1-F2 protein, encoded by an alternative reading frame in the PB1 polymerase gene, displays a high sequence polymorphism and is reported to contribute to viral pathogenesis in a sequence-specific manner. To gain insights into the functions of PB1-F2, the molecular structure of several PB1-F2 variants produced in Escherichia coli was investigated in different environments. Circular dichroism spectroscopy shows that all variants have a random coil secondary structure in aqueous solution. When incubated in trifluoroethanol polar solvent, all PB1-F2 variants adopt an alpha-helix-rich structure, whereas incubated in acetonitrile, a solvent of medium polarity mimicking the membrane environment, they display beta-sheet secondary structures. Incubated with asolectin liposomes and SDS micelles, PB1-F2 variants also acquire a beta-sheet structure. Dynamic light scattering revealed that the presence of beta-sheets is correlated with an oligomerization/aggregation of PB1-F2. Electron microscopy showed that PB1-F2 forms amorphous aggregates in acetonitrile. In contrast, at low concentrations of SDS, PB1-F2 variants exhibited various abilities to form fibers that were evidenced as amyloid fibers in a thioflavin T assay. Using a recombinant virus and its PB1-F2 knock-out mutant, we show that PB1-F2 also forms amyloid structures in infected cells. Functional membrane permeabilization assays revealed that the PB1-F2 variants can perforate membranes at nanomolar concentrations but with activities found to be sequence-dependent and not obviously correlated with their differential ability to form amyloid fibers. All of these observations suggest that PB1-F2 could be involved in physiological processes through different pathways, permeabilization of cellular membranes, and amyloid fiber formation. PMID:20172856

  16. Serum S-100? protein as a biomarker for brain damage in patients with encephalopathy

    International Nuclear Information System (INIS)

    Cerebrospinal fluid concentrations of S-100? protein, an acidic calcium-binding protein found in astrocytes and Schwann cells, increase after central nervous system damage. Serum S-100? protein, thus, has been expected to be a biochemical marker of brain cell damage. Several reports show a relation between severity of head injury and serum S-100? protein levels, although, there are still not significant advances in the study of S-100? regarding the prediction of the clinical outcome in brain diseases. The objective of the present study was to verify S-100? as a marker for the clinical outcome in patients with encephalopathy. Serum S-100? protein concentrations (pg/ml) were measured daily using enzyme-linked immunosorbent assay (ELISA) until discharge from the intensive care unit (ICU) in 82 patients (54 men, 28 women; age 20-93 years [mean 61.0±19.2]) with moderate or severe encephalopathy. There were 50 survivors and 32 non-survivors. S-100? levels were significantly lower in survivors (240.2 pg/ml) than in non-survivors (1,594.8 pg/ml) from day 1 until ICU discharge. The electroencephalogram (EEG) and computed tomography (CT) abnormalities were correlated with S-100? levels. The optimal cut-off value at 451.2 pg/ml calculated from receiver operating characteristic (ROC) curve analysis showed the sensitivity of 80.2% and specificity of 78.1% for ICU mortality. Our results indicate that serum S-100? protein could be a useful biomarker to assess brain damage and predict prognosis in patients with encephalopathy. (author)

  17. Synchrony in serum antibody response to conserved proteins of Streptococcus pneumoniae in young children.

    Science.gov (United States)

    Ren, Dabin; Almudevar, Anthony L; Pichichero, Michael E

    2015-01-01

    Conserved Streptococcus pneumoniae (Spn) proteins are currently under investigation as vaccine candidates. We recently identified a subset of children prone to frequent acute otitis media (AOM) that we refer to as stringently-defined otitis prone (sOP). We investigated the synchrony of serum antibody responses against 5 Spn protein vaccine antigens, PhtD, LytB, PcpA, PhtE, and PlyD1 resulting from nasopharyngeal colonization and AOM in sOP children (49 observations) and non-otitis prone (NOP) children (771 observations). Changes in serum IgG and IgM were quantitated with ELISA. IgG antibody concentrations against PhtD, PcpA, and PlyD1 rose in synchrony in sOP and NOP children; that is, the proteins appeared equally and highly immunogenic in children at age 6 to 15 months and then leveled off in their rise at 15 to 25 months. In contrast, rises in concentrations to PhtE and LytB were significantly slower and had not peaked in children even at 25 months of age, consistent with lower immunogenicity. Serum IgM responses against PhtD and PlyD1 were in synchrony in children at age 6-25 months old. PcpA did not induce a significant increase of serum IgM response in children, suggesting that primary responses to PcpA occurred prior to children attaining age 6 months old. PhtD, PcpA, and Ply elicit a synchronous natural acquisition of serum antibody in young children suggesting that a trivalent Spn protein vaccine combining PhtD, PcpA, and PlyD1 would be less likely to display antigen competition when administered as a combination vaccine in young children. PMID:25692218

  18. Using BAC transgenesis in zebrafish to identify regulatory sequences of the amyloid precursor protein gene in humans

    Directory of Open Access Journals (Sweden)

    Shakes Leighcraft A

    2012-09-01

    Full Text Available Abstract Background Non-coding DNA in and around the human Amyloid Precursor Protein (APP gene that is central to Alzheimer’s disease (AD shares little sequence similarity with that of appb in zebrafish. Identifying DNA domains regulating expression of the gene in such situations becomes a challenge. Taking advantage of the zebrafish system that allows rapid functional analyses of gene regulatory sequences, we previously showed that two discontinuous DNA domains in zebrafish appb are important for expression of the gene in neurons: an enhancer in intron 1 and sequences 28–31 kb upstream of the gene. Here we identify the putative transcription factor binding sites responsible for this distal cis-acting regulation, and use that information to identify a regulatory region of the human APP gene. Results Functional analyses of intron 1 enhancer mutations in enhancer-trap BACs expressed as transgenes in zebrafish identified putative binding sites of two known transcription factor proteins, E4BP4/ NFIL3 and Forkhead, to be required for expression of appb. A cluster of three E4BP4 sites at ?31?kb is also shown to be essential for neuron-specific expression, suggesting that the dependence of expression on upstream sequences is mediated by these E4BP4 sites. E4BP4/ NFIL3 and XFD1 sites in the intron enhancer and E4BP4/ NFIL3 sites at ?31?kb specifically and efficiently bind the corresponding zebrafish proteins in vitro. These sites are statistically over-represented in both the zebrafish appb and the human APP genes, although their locations are different. Remarkably, a cluster of four E4BP4 sites in intron 4 of human APP exists in actively transcribing chromatin in a human neuroblastoma cell-line, SHSY5Y, expressing APP as shown using chromatin immunoprecipitation (ChIP experiments. Thus although the two genes share little sequence conservation, they appear to share the same regulatory logic and are regulated by a similar set of transcription factors. Conclusion The results suggest that the clock-regulated and immune system modulator transcription factor E4BP4/ NFIL3 likely regulates the expression of both appb in zebrafish and APP in humans. It suggests potential human APP gene regulatory pathways, not on the basis of comparing DNA primary sequences with zebrafish appb but on the model of conservation of transcription factors.

  19. Studies on serum protein fractions of patients with uterine cervical cancer undergoing radiotherapy. Relationship between changes in serum protein fractions and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Onizuka, Keiichiro; Yamada, Hiroki; Uwada, Osamu; Umemura, Yoshiro; Kuroki, Masaomi; Tateyama, Hiromichi (Miyazaki Prefectural Hospital (Japan)); Migita, Shunsuke

    1994-09-01

    The correlation between changes in serum protein fractions and patient prognosis was evaluated. The subjects were 84 patients with uterine cervical cancer treated with combined external pelvic irradiation and intracavitary irradiation using a remote afterloading system (RALS). Twenty one normal women served as controls. Serum levels of 23 protein components were determined before and after radiotherapy. All patients were followed up for 4 to 8 years after radiotherapy. Pretreatment serum levels of prealbumin (Prealb), [alpha][sub 2]HS glycoprotein ([alpha][sub 2]HS), [alpha][sub 2]-plasmin inhibitor ([alpha][sub 2]PI), transferrin (Tf), plasminogen (Pmg), albumin (Alb), IgM, and hemopexin (Hx) were significantly lower in the group of cervical cancer patients than the control group; and serum levels of [alpha][sub 1]-antichymotrypsin ([alpha][sub 1]X), haptoglobin (Hp), C9, fibrinogen (Fib), ceruloplasmin (Cp), [alpha][sub 1]-acid glycoprotein ([alpha][sub 1]AG), [alpha][sub 1]-antitrypsin ([alpha][sub 1]AT), and C4 were elevated. At the completion of radiotherapy, HP, C4, and Fib levels were significantly lower than those before radiotherapy; Prealb, [alpha][sub 2]HS, and [alpha][sub 2]PI were elevated. In patients who survived 4 years and 8 years, pretreatment levels of Cp, [alpha][sub 1]AG, Hp, and C9 were significantly reduced and Tf was elevated, as compared with those who died within 4 years. In those who survived more than 4 years, posttreatment levels of [alpha][sub 1]AT, Hp, [alpha][sub 1]X, Cp, and C9 were significantly reduced, although the serum level of C4 was elevated. Survival positively correlated with pretreatment levels of Tf, Pmg, and [alpha][sub 1]AT, but negatively correlated with AT III, Cp, C1Inh, IgA, [alpha][sub 1]AG, and C9. For posttreatment levels, it positively correlated with Pmg, C4, Prealb, Alb, [alpha][sub 2]M, and Hp, but negatively correlated with Tf, [alpha][sub 2]PI, AT III, [alpha][sub 1]AT, C1Inh, C9, and IgA. (N.K.).

  20. Effects of repeated psychological stress training on the spectrum of serum protein expression in special troops

    Directory of Open Access Journals (Sweden)

    Li ZHANG

    2011-10-01

    Full Text Available Objective To investigate the effects of repeated psychological stress training on the serum protein expression in soldiers under mental stress.Methods Ninety-six male commando soldiers were randomly assigned into the common psychological training group,the circulation psychological training group and the control group(32 each.After a 4-week training,all the soldiers were instructed to attend an one-day high-intensity simulated anti-riot exercise,and 3 days later attended another unannounced high-intensity simulated anti-riot exercise.Blood samples were collected from all the soldiers within 4 hours after each exercise,and the changes in serum protein expression were determined and statistically analyzed by using surface-enhanced laser desorption/ionization time of flight mass spectrometry(SELDI-TOF-MS combined with ProteinChip technology.Results The variance analysis showed that significant differences existed among the three groups(P < 0.05 in the relative contents of proteins with M/Z values of 6417.8,9134.2,15171.9 and 14972.7D after the first anti-riot exercise,and the relative contents of all the above mentioned proteins increased in the circulatory psychological training group;meanwhile,markedly increasing trends of the relative contents of all the proteins were observed in the three groups after the second anti-riot exercise(P < 0.05,and in control group the relative contents of the 4 above mentioned proteins were significantly higher than those after the first anti-riot exercise.Conclusion Psychological training may up-regulate the expression of serum proteins that are down-regulated after stress,and the repeated high-intensity mental training can rapidly improve the soldiers’ ability to counteract stress.

  1. Uncoupling of M1 muscarinic receptor/G-protein interaction by amyloid beta(1-42).

    Czech Academy of Sciences Publication Activity Database

    Janí?ková, Helena; Rudajev, Vladimír; Zim?ík, Pavel; Jakubík, Jan; Tanila, H.; El-Fakahany, E. E.; Doležal, Vladimír

    2013-01-01

    Ro?. 67, April (2013), s. 272-283. ISSN 0028-3908 R&D Projects: GA ?R(CZ) GA305/09/0681; GA ?R(CZ) GBP304/12/G069; GA MŠk(CZ) 7E10060 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : Alzheimer ´s Disease * muscarinic receptors * G-proteins Subject RIV: ED - Physiology Impact factor: 4.819, year: 2013

  2. A DNA-promoted amyloid proteinopathy in Escherichia coli

    OpenAIRE

    Fernandez-Tresguerres, Elena; Moreno-Díaz De La Espina, Susana; Gasset-Rosa, Fátima; Giraldo, Rafael

    2010-01-01

    Abstract Protein amyloids arise from the conformational conversion and assembly of a soluble protein into fibrilar aggregates with a crossed ?-sheet backbone. Amyloid aggregates are able to replicate by acting as a template for the structural transformation and accretion of further protein molecules. In physicochemical terms, amyloids arguably constitute the simplest self-replicative macromolecular assemblies. Similarly to the mammalian proteins PrP and ?-synuclein, the winged-heli...

  3. Proteína amiloide A sérica como marcador de inflamación sistémica en pacientes con enfermedad periodontal / Serum amiloyd A protein as a systemic inflammatory marker in patients with periodontal disease

    Scientific Electronic Library Online (English)

    C., Romero-Sánchez; M.A., Uribe-Rivera; I.M., Velandia-Quintero; J., De Ávila; G.I., Lafaurie-Villamil.

    2013-04-01

    Full Text Available La respuesta de fase aguda es la reacción inflamatoria inmediata del huésped que contrarresta desafíos como lesión de los tejidos, infección y trauma. Los reactantes de fase aguda que han recibido mayor atención son: proteína C reactiva (PCR), componente sérico P, proteína amiloide sérica (AAS) y al [...] fa 1 ácido glicoproteína. Se ha establecido en décadas pasadas que las proteínas de fase aguda no solamente aparecen en procesos de enfermedades severas y agudas si no también en condiciones crónicas. El AAS es el principal componente de las placas amiloideas secundarias depositadas en los órganos principales como consecuencia de la enfermedad inflamatoria crónica. La familia de la AAS contiene un número de diferentes apolipoproteínas expresadas, las cuales son sintetizadas principalmente por el hígado. El aumento de AAS es considerado un marcador sistémico de enfermedades inflamatorias agudas y enfermedades crónicas que afecta la composición y función de lipoproteínas de alta densidad (HDL). Se ha demostrado que la intervención terapéutica en la periodontitis disminuye la inflamación y reduce el AAS significativamente y por consiguiente puede reducir el riesgo de enfermedad cardiovascular (ECV). Además es posible que pacientes con periodontitis, que presentan un aumento de la PCR y el AAS, representen un subgrupo específico en términos de riesgo para la aterosclerosis y enfermedad cardiovascular en comparación a los pacientes con periodontitis cuyos niveles plasmáticos de AAS son normales, estableciendo así una relación directa entre la enfermedad periodontal y los niveles de AAS. Abstract in english The acute phase response is the immediate host inflammatory reaction, which counteract challenges such as tissue injury, infection and trauma. The acute phase reactants that have receive most attention are: CRP, serum P component, serum amyloid protein and alpha 1 Acid glycoprotein. In past decades [...] it has been established that acute phase proteins appear not only in severe disease processes but also in severe and chronic conditions. The AAS is the main component of secondary amyloid plaques deposited in major organs as a result of chronic inflammatory disease. The family of SAA contains a number of different expressed apolipoproteins, which are synthesized by the liver. Increased SAA is a marker of systemic acute inflammatory diseases and chronic diseases affecting the composition and function of HDL. It was show that therapeutic intervention in periodontitis diseases decreases inflammation and reduces SAA and can therefore significantly reduce the risk of CVD. Besides it is possible that patients with periodontitis, who have an increase in the levels of CRP and SAA represent a specific subgroup in terms of risk for atherosclerosis and cardiovascular illness in comparison to patients with periodontitis, whose plasma levels of SAA are normal, establishing thus a direct relation between periodontal disease and the levels SAA.

  4. Serum protein profiles predict coronary artery disease in symptomatic patients referred for coronary angiography

    Directory of Open Access Journals (Sweden)

    LaFramboise William A

    2012-12-01

    Full Text Available Abstract Background More than a million diagnostic cardiac catheterizations are performed annually in the US for evaluation of coronary artery anatomy and the presence of atherosclerosis. Nearly half of these patients have no significant coronary lesions or do not require mechanical or surgical revascularization. Consequently, the ability to rule out clinically significant coronary artery disease (CAD using low cost, low risk tests of serum biomarkers in even a small percentage of patients with normal coronary arteries could be highly beneficial. Methods Serum from 359 symptomatic subjects referred for catheterization was interrogated for proteins involved in atherogenesis, atherosclerosis, and plaque vulnerability. Coronary angiography classified 150 patients without flow-limiting CAD who did not require percutaneous intervention (PCI while 209 required coronary revascularization (stents, angioplasty, or coronary artery bypass graft surgery. Continuous variables were compared across the two patient groups for each analyte including calculation of false discovery rate (FDR ? 1% and Q value (P value for statistical significance adjusted to ? 0.01. Results Significant differences were detected in circulating proteins from patients requiring revascularization including increased apolipoprotein B100 (APO-B100, C-reactive protein (CRP, fibrinogen, vascular cell adhesion molecule 1 (VCAM-1, myeloperoxidase (MPO, resistin, osteopontin, interleukin (IL-1?, IL-6, IL-10 and N-terminal fragment protein precursor brain natriuretic peptide (NT-pBNP and decreased apolipoprotein A1 (APO-A1. Biomarker classification signatures comprising up to 5 analytes were identified using a tunable scoring function trained against 239 samples and validated with 120 additional samples. A total of 14 overlapping signatures classified patients without significant coronary disease (38% to 59% specificity while maintaining 95% sensitivity for patients requiring revascularization. Osteopontin (14 times and resistin (10 times were most frequently represented among these diagnostic signatures. The most efficacious protein signature in validation studies comprised osteopontin (OPN, resistin, matrix metalloproteinase 7 (MMP7 and interferon ? (IFN? as a four-marker panel while the addition of either CRP or adiponectin (ACRP-30 yielded comparable results in five protein signatures. Conclusions Proteins in the serum of CAD patients predominantly reflected (1 a positive acute phase, inflammatory response and (2 alterations in lipid metabolism, transport, peroxidation and accumulation. There were surprisingly few indicators of growth factor activation or extracellular matrix remodeling in the serum of CAD patients except for elevated OPN. These data suggest that many symptomatic patients without significant CAD could be identified by a targeted multiplex serum protein test without cardiac catheterization thereby eliminating exposure to ionizing radiation and decreasing the economic burden of angiographic testing for these patients.

  5. Clinical significance of testing serum proteins related to liver functions in chronic HBV carriers

    Directory of Open Access Journals (Sweden)

    ZHANG Jiwang

    2015-04-01

    Full Text Available ObjectiveTo investigate the serum levels of liver function-related proteins (cholinesterase, ChE; album, Alb, prealbumin, PA; transferrin, TRF; ferritin, FRT; C-reactive protein, CRP; and ceruloplasmin, CER and assess their clinical diagnostic significance for chronic hepatitis B virus (HBV carriers. MethodsThe study selected 86 HBV carriers who were diagnosed in the Affiliated Yong-Chuan Hospital of Chongqing Medical University from January 2012 to July 2014 (the observation group. Additionally, 102 healthy individuals who underwent physical examination in the hospital were selected (the control group. Biochemical indices including serum ChE, Alb, PA, FRT, TRF, CRP, and CER levels were measured in both groups. Liver biopsy was performed in part of the observation group. Group comparison of continuous data was performed using the independent-samples t test. ResultsSerum CER levels in the observation and control groups were (0.20±0.04 g/L vs (0.29±0.06 g/L, showing a statistically significant difference (t=2.03, P=0.03. No significant differences occurred in the rest of biochemical indices between groups (P?0.05 for all. Serum CER levels were significantly decreased in patients with higher severity of liver inflammation and fibrosis ?(0.23±0.01 g/L vs (0.18±0.02 g/L, t=-2.6, P=0?01; (0.22±0.02 g/L vs (0.17±0.04 g/L, t=-3.2, P=0.004?. ConclusionThe change in serum CER level can reflect the severity of liver inflammation and fibrosis in the early stage. Thus, serum CER level may become an important index for early diagnosis and treatment of HBV carriers.

  6. Some acute phase reactants and cholesterol levels in serum of patient with Crimean-Congo haemorrhagic fever

    OpenAIRE

    Sari, ?smail; Bak?r, Sevtap; Engin, Aynur; Ayd?n, Hüseyin; Poyraz, Ömer

    2013-01-01

    The purpose of this study is to determine erythrocyte sedimentation rate (ESR), C - reactive protein (CRP), serum amyloid-A (SAA) and cholesterol levels in patients with Crimean-Congo Hemorrhagic Fever (CCHF) and determine the relationship of these parameters with the severity of disease.

  7. Quantification of Borrelia burgdorferi Membrane Proteins in Human Serum: A New Concept for Detection of Bacterial Infection.

    Science.gov (United States)

    Cheung, Crystal S F; Anderson, Kyle W; Benitez, Kenia Y Villatoro; Soloski, Mark J; Aucott, John N; Phinney, Karen W; Turko, Illarion V

    2015-11-17

    The Borrelia burgdorferi spirochete is the causative agent of Lyme disease, the most common tick-borne disease in the United States. The low abundance of bacterial proteins in human serum during infection imposes a challenge for early proteomic detection of Lyme disease. To address this challenge, we propose to detect membrane proteins released from bacteria due to disruption of their plasma membrane triggered by the innate immune system. These membrane proteins can be separated from the bulk of serum proteins by high-speed centrifugation causing substantial sample enrichment prior to targeted protein quantification using multiple reaction monitoring mass spectrometry. This new approach was first applied to detection of B. burgdorferi membrane proteins supplemented in human serum. Our results indicated that detection of B. burgdorferi membrane proteins, which are ?10(7) lower in abundance than major serum proteins, is feasible. Therefore, quantitative analysis was also carried out for serum samples from three patients with acute Lyme disease. We were able to demonstrate the detection of ospA, the major B. burgdorferi lipoprotein at the level of 4.0 fmol of ospA/mg of serum protein. The results confirm the concept and suggest that the proposed approach can be expanded to detect other bacterial infections in humans, particularly where existing diagnostics are unreliable. PMID:26491962

  8. Towards a Pharmacophore for Amyloid

    Energy Technology Data Exchange (ETDEWEB)

    Landau, Meytal; Sawaya, Michael R.; Faull, Kym F.; Laganowsky, Arthur; Jiang, Lin; Sievers, Stuart A.; Liu, Jie; Barrio, Jorge R.; Eisenberg, David (UCLA)

    2011-09-16

    Diagnosing and treating Alzheimer's and other diseases associated with amyloid fibers remains a great challenge despite intensive research. To aid in this effort, we present atomic structures of fiber-forming segments of proteins involved in Alzheimer's disease in complex with small molecule binders, determined by X-ray microcrystallography. The fiber-like complexes consist of pairs of {beta}-sheets, with small molecules binding between the sheets, roughly parallel to the fiber axis. The structures suggest that apolar molecules drift along the fiber, consistent with the observation of nonspecific binding to a variety of amyloid proteins. In contrast, negatively charged orange-G binds specifically to lysine side chains of adjacent sheets. These structures provide molecular frameworks for the design of diagnostics and drugs for protein aggregation diseases. The devastating and incurable dementia known as Alzheimer's disease affects the thinking, memory, and behavior of dozens of millions of people worldwide. Although amyloid fibers and oligomers of two proteins, tau and amyloid-{beta}, have been identified in association with this disease, the development of diagnostics and therapeutics has proceeded to date in a near vacuum of information about their structures. Here we report the first atomic structures of small molecules bound to amyloid. These are of the dye orange-G, the natural compound curcumin, and the Alzheimer's diagnostic compound DDNP bound to amyloid-like segments of tau and amyloid-{beta}. The structures reveal the molecular framework of small-molecule binding, within cylindrical cavities running along the {beta}-spines of the fibers. Negatively charged orange-G wedges into a specific binding site between two sheets of the fiber, combining apolar binding with electrostatic interactions, whereas uncharged compounds slide along the cavity. We observed that different amyloid polymorphs bind different small molecules, revealing that a cocktail of compounds may be required for future amyloid therapies. The structures described here start to define the amyloid pharmacophore, opening the way to structure-based design of improved diagnostics and therapeutics.

  9. Comparative evaluation of hmopolesis and serum proteins from dogs with transmissible venereal tumor by natural ocorrence and induced by alogenic transplant

    International Nuclear Information System (INIS)

    The objective of this study was to evaluate the haemopoiesis and total serum proteins of dogs with canine Transmissible Venereal Tumour (TVT) (naturally occurring or induced by allogenic transplant). Complete haemogram, bone marrow evaluation, total serum protein, albumin determination and electrophoretic fractionation of serum proteins were performed. Results revealed normocytic normochromic anaemia and thrombocytopenia in dogs with naturally occurring TVT

  10. Defined DNA sequences promote the assembly of a bacterial protein into distinct amyloid nanostructures

    OpenAIRE

    Giraldo, Rafael

    2007-01-01

    RepA, the replication initiator protein of Pseudomonas pPS10 plasmid, is made of two winged-helix (WH) domains. RepA dimers undergo a structural transformation upon binding to origin DNA sequences (iterons), resulting in monomerization and ?-helix into ?-strand conversion. This affects the N-terminal domain (WH1) and generates a metastable intermediate. Here it is shown that the interaction of short dsDNA oligonucleotides, including iteron or operator RepA targets, with the isolated WH1 domai...

  11. Formation of amyloid fibrils by peptides derived from the bacterial cold shock protein CspB.

    OpenAIRE

    Gross, M; Wilkins, D.K.; Pitkeathly, M. C.; Chung, E. W.; Higham, C.; Clark, A.; Dobson, C. M.

    1999-01-01

    Three peptides covering the sequence regions corresponding to the first two (CspB-1), the first three (CspB-2), and the last two (CspB-3) beta-strands of CspB, the major cold shock protein of Bacillus subtilis, have been synthesized and analyzed for their conformations in solution and for their precipitation behavior. The peptides are nearly insoluble in water, but highly soluble in aqueous solutions containing 50% acetonitrile (pH 4.0). Upon shifts of the solvent condition toward lower or hi...

  12. The influence of childhood protein energy malnutrition on serum ghrelin and leptin levels

    International Nuclear Information System (INIS)

    Protein-energy malnutrition (PEM) is a clinical problem caused by inadequate intake of one or more nutritional elements and remains as one of the most important health problems in developing countries. The aim of this study is to investigate the influence of PEM on ghrelin and leptin levels and to determine the relationships of ghrelin and leptin concentrations with anthropometric measurements in malnourished children. The study group consisted of 24 infants diagnosed as PEM. They were classified into marasmic group (10), kwashiorkor group (8) and marasmic kwashiorkor group (b). Ten healthy infants were enrolled as the control group. Serum ghrelin was evaluated by enzyme linked immuno absorbent assay (ELISA) while serum leptin was determined by radioimmunoassay (RIA). Patients with PEM established a significantly lower midarm circumference, skin fold thickness, (W/A) Z, (W/H) Z, BMI, total proteins, serum albumin, cholesterol and triglycerides compared with the age-matched control group. Markedly elevated mean serum ghrelin levels (448.7± 185.82, 293.83±155.02 and 354.1±90.1 vs 20.97± 8.61 pg/ml, p

  13. Peptide Detection of Fungal Functional Amyloids in Infected Tissue

    OpenAIRE

    Garcia-Sherman, Melissa C.; Lysak, Nataliya; Filonenko, Alexandra; Richards, Hazel; Sobonya, Richard E.; Klotz, Stephen A; Lipke, Peter N.

    2014-01-01

    Many fungal cell adhesion proteins form functional amyloid patches on the surface of adhering cells. The Candida albicans Agglutinin-like sequence (Als) adhesins are exemplars for this phenomenon, and have amyloid forming sequences that are conserved between family members. The Als5p amyloid sequence mediates amyloid fibril formation and is critical for cell adhesion and biofilm formation, and is also present in the related adhesins Als1p and Als3p. We have developed a fluorescent peptide ...

  14. A short Id2 protein fragment containing the nuclear export signal forms amyloid-like fibrils

    International Nuclear Information System (INIS)

    The negative regulator of DNA-binding/cell-differentiation Id2 is a small protein containing a central helix-loop-helix (HLH) motif and a C-terminal nuclear export signal (NES). Whereas the former is essential for Id2 dimerization and nuclear localization, the latter is responsible for the transport of Id2 from the nucleus to the cytoplasm. Whereas the isolated Id2 HLH motif is highly helical, large C-terminal Id2 fragments including the NES sequence are either unordered or aggregation-prone. To study the conformational properties of the isolated NES region, we synthesized the Id2 segment 103-124. The latter was insoluble in water and only temporarily soluble in water/alcohol mixtures, where it formed quickly precipitating ?-sheets. Introduction of a positively charged N-terminal tail prevented aggressive precipitation and led to aggregates consisting of long fibrils that bound thioflavin T. These results show an interesting structural aspect of the Id2 NES region, which might be of significance for both protein folding and function

  15. Chemokines, macrophage inflammatory protein-2 and stromal cell-derived factor-1{alpha}, suppress amyloid {beta}-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Raman, Dayanidhi; Milatovic, Snjezana-Zaja [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Milatovic, Dejan [Department of Pediatrics/Pediatric Toxicology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Splittgerber, Ryan [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States); Fan, Guo-Huang [Department of Neurobiology and Neurotoxicology, Meharry Medical College, Nashville, TN 37221 (United States); Richmond, Ann, E-mail: ann.richmond@vanderbilt.edu [VA Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN 37232 (United States)

    2011-11-15

    Alzheimer's disease (AD) is characterized by a progressive cognitive decline and accumulation of neurotoxic oligomeric peptides amyloid-{beta} (A{beta}). Although the molecular events are not entirely known, it has become evident that inflammation, environmental and other risk factors may play a causal, disruptive and/or protective role in the development of AD. The present study investigated the ability of the chemokines, macrophage inflammatory protein-2 (MIP-2) and stromal cell-derived factor-1{alpha} (SDF-1{alpha}), the respective ligands for chemokine receptors CXCR2 and CXCR4, to suppress A{beta}-induced neurotoxicity in vitro and in vivo. Pretreatment with MIP-2 or SDF-1{alpha} significantly protected neurons from A{beta}-induced dendritic regression and apoptosis in vitro through activation of Akt, ERK1/2 and maintenance of metalloproteinase ADAM17 especially with SDF-1{alpha}. Intra-cerebroventricular (ICV) injection of A{beta} led to reduction in dendritic length and spine density of pyramidal neurons in the CA1 area of the hippocampus and increased oxidative damage 24 h following the exposure. The A{beta}-induced morphometric changes of neurons and increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes, were significantly inhibited by pretreatment with the chemokines MIP-2 or SDF-1{alpha}. Additionally, MIP-2 or SDF-1{alpha} was able to suppress the aberrant mislocalization of p21-activated kinase (PAK), one of the proteins involved in the maintenance of dendritic spines. Furthermore, MIP-2 also protected neurons against A{beta} neurotoxicity in CXCR2-/- mice, potentially through observed up regulation of CXCR1 mRNA. Understanding the neuroprotective potential of chemokines is crucial in defining the role for their employment during the early stages of neurodegeneration. -- Research highlights: Black-Right-Pointing-Pointer Neuroprotective ability of the chemokines MIP2 and CXCL12 against A{beta} toxicity. Black-Right-Pointing-Pointer MIP-2 or CXCL12 prevented dendritic regression and apoptosis in vitro. Black-Right-Pointing-Pointer Neuroprotection through activation of Akt, ERK1/2 and maintenance of ADAM17. Black-Right-Pointing-Pointer Neuroprotection of hippocampal pyramidal neurons in vivo by MIP-2 or CXCL12. Black-Right-Pointing-Pointer MIP-2 or CXCL12 prevent elevation of F2-Isoprostanes against A{beta} treatment.

  16. Depolymerization of insulin amyloid fibrils by albumin-modified magnetic fluid

    International Nuclear Information System (INIS)

    Pathogenesis of amyloid-related diseases is associated with the presence of protein amyloid deposits. Insulin amyloids have been reported in a patient with diabetes undergoing treatment by injection of insulin and causes problems in the production and storage of this drug and in application of insulin pumps. We have studied the interference of insulin amyloid fibrils with a series of 18 albumin magnetic fluids (MFBSAs) consisting of magnetite nanoparticles modified by different amounts of bovine serum albumin (w/w BSA/Fe3O4 from 0.005 up to 15). We have found that MFBSAs are able to destroy amyloid fibrils in vitro. The extent of fibril depolymerization was affected by nanoparticle physical–chemical properties (hydrodynamic diameter, zeta potential and isoelectric point) determined by the BSA amount present in MFBSAs. The most effective were MFBSAs with lower BSA/Fe3O4 ratios (from 0.005 to 0.1) characteristic of about 90% depolymerizing activity. For the most active magnetic fluids (ratios 0.01 and 0.02) the DC50 values were determined in the range of low concentrations, indicating their ability to interfere with insulin fibrils at stoichiometric concentrations. We assume that the present findings represent a starting point for the application of the active MFBSAs as therapeutic agents targeting insulin amyloidosis. (paper)

  17. Yersinia enterocolitica Serum Resistance Proteins YadA and Ail Bind the Complement Regulator C4b-Binding Protein

    OpenAIRE

    Kirjavainen, Vesa; Jarva, Hanna; Biedzka-Sarek, Marta; Blom, Anna M; Skurnik, Mikael; Meri, Seppo

    2008-01-01

    Many pathogens are equipped with factors providing resistance against the bactericidal action of complement. Yersinia enterocolitica, a Gram-negative enteric pathogen with invasive properties, efficiently resists the deleterious action of human complement. The major Y. enterocolitica serum resistance determinants include outer membrane proteins YadA and Ail. Lipopolysaccharide (LPS) O-antigen (O-ag) and outer core (OC) do not contribute directly to complement resistance. The aim of this study...

  18. Effects of Egg White Protein Supplementation on Muscle Strength and Serum Free Amino Acid Concentrations

    Directory of Open Access Journals (Sweden)

    Yukari Kawano

    2012-10-01

    Full Text Available The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM, one repetition maximum (1RM muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal and carbohydrate group (17.5 g maltodextrin, 78 kcal. Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength.

  19. Chromatographic adsorption of serum albumin and antibody proteins in cryogels with benzyl-quaternary amine ligands.

    Science.gov (United States)

    Yun, Junxian; Cheng, Xiuhong; Ye, Jialei; Shen, Shaochuan; Yang, Gensheng; Yao, Kejian; Kirsebom, Harald; Lin, Dong-Qiang; Guan, Yi-Xin; Yao, Shan-Jing

    2015-02-13

    The preparation and characterization of mixed-mode adsorbents for a typical separation purpose are of great importance in bioseparation areas. In this work, we prepared a new monolithic cryogel with a combination of ion-exchange and hydrophobic functions by employing benzyl-quaternary amine groups. The fundamental cryogel properties, protein equilibrium adsorption isotherm and chromatographic adsorption in the cryogel were measured experimentally. The results showed that, by using bovine serum album as the model protein, the dual functional cryogel has protein binding capability even in salt solution and the buffer with pH close or below the protein isoelectric point due to both the electrostatic and hydrophobic interactions. A capillary-based adsorption model was developed, which provided satisfied insights of the microstructure, axial dispersion, mass transfer as well as protein adsorption characteristics within the cryogel bed. The chromatographic isolation of bioactive proteins from rabbit blood serum was carried out by the cryogel. Immunoglobulin G antibody with a purity of 98.2% and albumin with a purity of 96.8% were obtained, indicating that the cryogel could be an interesting and promising adsorbent in bioseparation areas. PMID:25618356

  20. Muscular sufficiency, serum protein, enzymes and bioenergetic studies in chronic malnutrition

    International Nuclear Information System (INIS)

    Muscle sufficiency was significantly lower in 1336 children with chronic malnutrition of moderate to severe degree. 18 children with a chronic moderate degree of malnutrition and 8 well-nourished age-matched controls were selected for biochemical and 31-phosphorus magnetic resonance spectroscopy (31-P MRS) studies. The results shows that: a) serum total protein, albumin, iron, calcium and inorganic phosphate were similar in both groups; b) serum enzyme levels were significantly increased in the malnuourished group; c) 31-P MRS showed significantly higher means for total ATP, ?-ATP, ?-ATP and inorganic phosphate for the malnourished compared to the control group. In chronic malnutrition, proteins are maintained by degradation in muscle resulting in release of amino acids and enzymes. 31-P MRS studies showing increases in total ATP, ?-ATP and inorganic phosphate and a decrease in phosphocreatine suggest that ATP is maintained at the cost of phosphocreatine. 22 refs., 4 tabs. 1 fig