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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.

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    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. 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

  4. 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

  5. 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

  6. Serum amyloid A is a retinol binding protein that transports retinol during bacterial infection.

    Science.gov (United States)

    Derebe, Mehabaw G; Zlatkov, Clare M; Gattu, Sureka; Ruhn, Kelly A; Vaishnava, Shipra; Diehl, Gretchen E; MacMillan, John B; Williams, Noelle S; Hooper, Lora V

    2014-01-01

    Retinol plays a vital role in the immune response to infection, yet proteins that mediate retinol transport during infection have not been identified. Serum amyloid A (SAA) proteins are strongly induced in the liver by systemic infection and in the intestine by bacterial colonization, but their exact functions remain unclear. Here we show that mouse and human SAAs are retinol binding proteins. Mouse and human SAAs bound retinol with nanomolar affinity, were associated with retinol in vivo, and limited the bacterial burden in tissues after acute infection. We determined the crystal structure of mouse SAA3 at a resolution of 2 Å, finding that it forms a tetramer with a hydrophobic binding pocket that can accommodate retinol. Our results thus identify SAAs as a family of microbe-inducible retinol binding proteins, reveal a unique protein architecture involved in retinol binding, and suggest how retinol is circulated during infection. PMID:25073702

  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. Medicated rat serum containing Gengnianchun decoction reduces apoptosis of pheochromocytoma cells insulted by amyloid beta protein

    OpenAIRE

    Li, Jun

    2010-01-01

    Objective: To investigate the effects of medicated rat serum containing Gengnianchun (GNC) decoction and its protection to pheochromocytoma cells (PC12 cells) from amyloid beta (Aβ)25-35-insulted apoptosis and to find the possible mechanism.Methods: Medicated rat serum was prepared by administering ovariectomized Sprague-Dawley (SD) rats with GNC decoction. The effects of medicated rat serum on viability of PC12 cells were evaluated by cell counting kit-8 (CCK-8) assay. The PC12 cells were cu...

  10. 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 βA4 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 βA4 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 βA4, affinity columns were prepared by immobilizing GST- βA4 and GST respectively. Using the affinity columns and human serum, we have observed an interaction of βA4 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 βA4 to interact with serum protein strongly support the notion that such an interaction may underlie with the biological function of βA4 in vivo.

  11. Medicated rat serum containing Gengnianchun decoction reduces apoptosis of pheochromocytoma cells insulted by amyloid beta protein

    Directory of Open Access Journals (Sweden)

    Jun LI

    2010-05-01

    Full Text Available Objective: To investigate the effects of medicated rat serum containing Gengnianchun (GNC decoction and its protection to pheochromocytoma cells (PC12 cells from amyloid beta (Aβ25-35-insulted apoptosis and to find the possible mechanism.Methods: Medicated rat serum was prepared by administering ovariectomized Sprague-Dawley (SD rats with GNC decoction. The effects of medicated rat serum on viability of PC12 cells were evaluated by cell counting kit-8 (CCK-8 assay. The PC12 cells were cultured with different doses of Aβ25-35 to induce a model of Alzheimer's disease in vitro. Then, the protective effects of medicated rat serum on Aβ25-35-insulted PC12 cells were evaluated by using CCK-8 assay to detect the cell viability, using Annexin Ⅴ-fluorescein isothiocyanate (FITC/propidium iodide (PI flow cytometry to detect cell apoptosis rate and using Western blotting assay to analyze the expressions of Bcl-2, Bax and active caspase-3 proteins.Results: PC12 cells cultured with 20% medicated rat serum containing GNC decoction for 24 h or 48 h had higher viability than those cultured with normal culture medium (P<0.05. After 24- or 48-hour treatment of different concentrations of Aβ25-35, cell viabilities were all decreased as compared with normal medium (P<0.05. Cells underwent apoptosis, which showed the neurotoxicity of Aβ25-35. The cell apoptosis induced by Aβ25-35 was significantly decreased in PC12 cells which were pretreated with 20% medicated rat serum or nerve growth factor (NGF according to CCK-8 assay and Annexin Ⅴ-FITC/PI flow cytometry (P<0.05. The ratio of Bax expression to Bcl-2 expression and the expression of active caspase-3 were decreased in the cells treated with medicated serum or NGF as compared with the cells cultured with Aβ25-35 only.Conclusion: The GNC-medicated rat serum at concentration of 20% can promote viability of Aβ25-35-insulted PC12 cells and decrease the cell apoptosis by regulating the expressions of Bcl-2, Bax and active caspase 3.

  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; 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...

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

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    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...

  14. Serum Amyloid A Protein Concentration in Blood is Influenced by Genetic Differences in the Cheetah (Acinonyx jubatus).

    Science.gov (United States)

    Franklin, Ashley D; Schmidt-Küntzel, Anne; Terio, Karen A; Marker, Laurie L; Crosier, Adrienne E

    2016-03-01

    Systemic amyloid A (AA) amyloidosis is a major cause of morbidity and mortality among captive cheetahs. The self-aggregating AA protein responsible for this disease is a byproduct of serum amyloid A (SAA) protein degradation. Transcriptional induction of the SAA1 gene is dependent on both C/EBP? and NF-?B cis-acting elements within the promoter region. In cheetahs, 2 alleles exist for a single guanine nucleotide deletion in the putative NF-?B binding site. In this study, a novel genotyping assay was developed to screen for the alleles. The results show that the SAA1A (-97delG) allele is associated with decreased SAA protein concentrations in the serum of captive cheetahs (n = 58), suggesting genetic differences at this locus may be affecting AA amyloidosis prevalence. However, there was no significant difference in the frequency of the SAA1A (-97delG) allele between individuals confirmed AA amyloidosis positive versus AA amyloidosis negative at the time of necropsy (n = 48). Thus, even though there is evidence that having more copies of the SAA1A (-97delG) allele results in a potentially protective decrease in serum concentrations of SAA protein in captive cheetahs, genotype is not associated with this disease within the North American population. These results suggest that other factors are playing a more significant role in the pathogenesis of AA amyloidosis among captive cheetahs. PMID:26585380

  15. 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...

  16. 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.

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

    OpenAIRE

    Wang, Wen-Jun

    2010-01-01

    Obiective: To observe the effects of serum containing Gengnianchun (GNC) decoction, a compound traditional Chinese herbal medicine, and its monomers (paeoniflorin, berberine, timosaponin A-Ⅲ and icariin) on neurotoxicity in PC12 cells induced by amyloid beta-protein (Aβ).Methods: Injury of PC12 cells was induced by in incubating with Aβ25-35 in vitro. Ovariectomized rats were intragastrically administered with GNC decoction twice daily for 5 days and then sera were obtained. Different conce...

  18. 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

  19. Serum amyloid P inhibits dermal wound healing

    Science.gov (United States)

    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 ...

  20. 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...

  1. 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

  2. How does serum amyloid P component get into the brain?

    OpenAIRE

    Judit Laszy; László Németh; Gábor Szabó

    2010-01-01

    Serum amyloid P component (SAP), a circulating pentraxin produced by the liver, does not penetrate the brain in physiological conditions. In Alzheimer’s disease SAP is one of the components of the amyloid plaques and stabilizes the protein deposits. The goal of this study was to investigate the transport of SAP in animal experiments and in a rat in vitro model of the blood-brain barrier using primary cell cultures. No human SAP (hSAP) could be detected in rat brain sections by immunohis...

  3. 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

    Directory of Open Access Journals (Sweden)

    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.

  4. Protein Polymers and Amyloids

    DEFF Research Database (Denmark)

    Risør, Michael Wulff

    2014-01-01

    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 α1AT folding or in the native state represents a therapeutic strategy to prevent polymerization. Using Molecular Dynamics...... 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 α1AT to understand its role in the disease-causing polymerization events and to investigate the amyloid fibril formation of a...

  5. 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...

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

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    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.

  7. 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.)

  8. 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.

  9. 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; Andersen, Ove; Danielsen, B; Svehag, SE

    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...

  10. 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...

  11. 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...

  12. 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.

  13. 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-Ⅲ and icariin on neurotoxicity in PC12 cells induced by amyloid beta-protein (Aβ.Methods: Injury of PC12 cells was induced by in incubating with Aβ25-35 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 Aβ25-35 was detemined by culturing PC12 cells with different concentrations of Aβ25-35. Then, the activity of PC12 cells with Aβ25-35-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 Aβ25-35-induced early apoptosis of PC12 cells.Results: After Aβ25-35 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 Aβ25-35 concentration- and timedependently. Aβ25-35 at concentration of 20 μmol/ 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 μmol/L berberin and monomer mixture 3 including 1 mg/mL paeoniflorin, 1 μmol/L berberine, 1 μmol/L timosaponin and 1 ng/mL icariine could antagonize neurotoxicity induced by Aβ25-35. Moreover, they could inhibit Aβ25-35-induced early apoptosis of PC12 cells, with the effect of 20% serum containing GNC decoction better than 0.1 μmol/L berberine and monomer mixture 3.Conclusion: Serum containing GNC decoction at 20% concentration has the potential neuroprotective effect on Aβ-induced cellular impairment. The serum containing GNC decoction was found to be stronger in action than the main monomers.

  14. 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...

  15. Serum Amyloid A Truncations in Type 2 Diabetes Mellitus

    Science.gov (United States)

    Yassine, Hussein N.; Trenchevska, Olgica; He, Huijuan; Borges, Chad R.; Nedelkov, Dobrin; Mack, Wendy; Kono, Naoko; Koska, Juraj; Reaven, Peter D.; Nelson, Randall W.

    2015-01-01

    Serum Amyloid A (SAA) is an acute phase protein complex consisting of several abundant isoforms. The N- terminus of SAA is critical to its function in amyloid formation. SAA is frequently truncated, either missing an arginine or an arginine-serine dipeptide, resulting in isoforms that may influence the capacity to form amyloid. However, the relative abundance of truncated SAA in diabetes and chronic kidney disease is not known. Methods Using mass spectrometric immunoassay, the abundance of SAA truncations relative to the native variants was examined in plasma of 91 participants with type 2 diabetes and chronic kidney disease and 69 participants without diabetes. Results The ratio of SAA 1.1 (missing N-terminal arginine) to native SAA 1.1 was lower in diabetics compared to non-diabetics (p = 0.004), and in males compared to females (phemoglobin (r = ?0.32, p<0.001) and triglyceride concentrations (r = ?0.37, p<0.001), and positively correlated with HDL cholesterol concentrations (r = 0.32, p<0.001). Conclusion The relative abundance of the N-terminal arginine truncation of SAA1.1 is significantly decreased in diabetes and negatively correlates with measures of glycemic and lipid control. PMID:25607823

  16. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ossetrova, N.I., E-mail: ossetrova@afrri.usuhs.mil [Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bldg. 42, Bethesda, MD 20889-5603 (United States); Sandgren, D.J.; Blakely, W.F. [Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bldg. 42, Bethesda, MD 20889-5603 (United States)

    2011-09-15

    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 {sup 60}Co {gamma}-rays (0.55 Gy min{sup -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 {approx}1 Gy and {approx}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.

  18. 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.

  19. 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.

  20. 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...

  1. 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...

  2. Expression of serum amyloid a in equine wounds

    DEFF Research Database (Denmark)

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

    2010-01-01

    higher (P < 0.01) in limb wounds healing with EGT formation than in body and limb wounds with normal healing. In body wounds and limb wounds with normal healing SAA expression was very low, in EGT SAA expression levels varied from low to very high. CONCLUSIONS SAA is a major equine acute phase protein......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 divided in three groups: body wounds (regio brachii), unbandaged limb wounds (normal healing), and...

  3. 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...

  4. 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.

  5. 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

  6. 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...

  7. Serum Amyloid A Is a Marker for Pulmonary Involvement in Systemic Sclerosis

    OpenAIRE

    Lakota, Katja; Carns, Mary; Podlusky, Sofia; Mrak-Poljsak, Katjusa; Hinchcliff, Monique; Lee, Jungwha; Tomsic, Matija; Sodin-Semrl, Snezna; Varga, John

    2015-01-01

    Inflammation in systemic sclerosis (SSc) is a prominent, but incompletely characterized feature in early stages of the disease. The goal of these studies was to determine the circulating levels, clinical correlates and biological effects of the acute phase protein serum amyloid A (SAA), a marker of inflammation, in patients with SSc. Circulating levels of SAA were determined by multiplex assays in serum from 129 SSc patients and 98 healthy controls. Correlations between SAA levels and clinica...

  8. 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...

  9. How does serum amyloid P component get into the brain?

    Directory of Open Access Journals (Sweden)

    Judit Laszy

    2010-04-01

    Full Text Available Serum amyloid P component (SAP, a circulating pentraxin produced by the liver, does not penetrate the brain in physiological conditions. In Alzheimer’s disease SAP is one of the components of the amyloid plaques and stabilizes the protein deposits. The goal of this study was to investigate the transport of SAP in animal experiments and in a rat in vitro model of the blood-brain barrier using primary cell cultures. No human SAP (hSAP could be detected in rat brain sections by immunohistochemistry or by ELISA in healthy animals after intravenous injection of the pentraxin. Furthermore, when hSAP was injected to the left hippocampus of rats it was rapidly effluxed. Rat brain endothelial cells took up FITC-labelled hSAP from both luminal and abluminal direction with a higher luminal release indicating active efflux mechanism. We demonstrated that the blood-brain barrier permeability is increased to hSAP in Salmonella typhimurium lipopolysaccharide-injected mice. Lipopolysaccharide induced hSAP extravasation to brain parenchyma and also increased the number of cerebral vessels labelled with FITC-hSAP, while no hSAP leakage to brain was seen in vehicle-treated mice. Our data indicate, that active efflux mechanisms at the level of the blood-brain barrier protect the brain from SAP penetration in physiological conditions. Damage to the protective mechanisms of the blood-brain barrier due to pathological insults, like inflammation may result in a higher SAP concentration in brain and can contribute to the pathomechanism of neurodegenerative diseases, like Alzheimer’s disease.

  10. 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...

  11. 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.

  12. 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

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. Uropathogenic Escherichia coli Induces Serum Amyloid A in Mice following Urinary Tract and Systemic Inoculation

    OpenAIRE

    Erman, Andreja; Lakota, Katja; Mrak-Poljsak, Katjusa; Blango, Matthew G.; Krizan-Hergouth, Veronika; Matthew A. Mulvey; Sodin-Semrl, Snezna; Veranic, Peter

    2012-01-01

    Serum amyloid A (SAA) is an acute phase protein involved in the homeostasis of inflammatory responses and appears to be a vital host defense component with protective anti-infective properties. SAA expression remains poorly defined in many tissues, including the urinary tract which often faces bacterial challenge. Urinary tract infections (UTIs) are usually caused by strains of uropathogenic Escherichia coli (UPEC) and frequently occur among otherwise healthy individuals, many of whom experie...

  18. Reduction of Bleomycin-Induced Pulmonary Fibrosis by Serum Amyloid P

    OpenAIRE

    Pilling, Darrell; Roife, David; wang, Min; Ronkainen, Sanna D.; Crawford, Jeff R.; Travis, Elizabeth L.; Gomer, Richard H

    2007-01-01

    Fibrotic diseases such as scleroderma, severe chronic asthma, pulmonary fibrosis, and cardiac fibrosis kill tens of thousands of people each year in the U.S. alone. Growing evidence suggests that in fibrotic lesions, a subset of blood monocytes enters the tissue and differentiates into fibroblast-like cells called fibrocytes, causing tissue dysfunction. We previously found that a plasma protein called serum amyloid P (SAP) inhibits fibrocyte differentiation in vitro. Bleomycin treatment is a ...

  19. Persistent Lung Inflammation and Fibrosis in Serum Amyloid P Component (Apcs-/-) Knockout Mice

    OpenAIRE

    Pilling, Darrell; Gomer, Richard H

    2014-01-01

    Fibrosing diseases, such as pulmonary fibrosis, cardiac fibrosis, myelofibrosis, liver fibrosis, and renal fibrosis are chronic and debilitating conditions and are an increasing burden for the healthcare system. Fibrosis involves the accumulation and differentiation of many immune cells, including macrophages and fibroblast-like cells called fibrocytes. The plasma protein serum amyloid P component (SAP; also known as pentraxin-2, PTX2) inhibits fibrocyte differentiation in vitro, and injectio...

  20. Distinct Fc? receptors mediate the effect of Serum Amyloid P on neutrophil adhesion and fibrocyte differentiation

    OpenAIRE

    Cox, Nehemiah; Pilling, Darrell; Gomer, Richard H

    2014-01-01

    The plasma protein Serum Amyloid P (SAP) reduces neutrophil adhesion, inhibits the differentiation of monocytes into fibroblast-like cells called fibrocytes, and promotes phagocytosis of cell debris by macrophages. Together, these effects of SAP reduce key aspects of inflammation and fibrosis, and SAP injections improve lung function in pulmonary fibrosis patients. SAP functions are mediated in part by Fc? receptors, but the contribution of each Fc? receptor is not fully understood. We found ...

  1. 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.

  2. 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 ...

  3. 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...

  4. 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

  5. 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...

  6. In Vitro Polymerization of a Functional Escherichia coli Amyloid Protein*

    OpenAIRE

    Wang, Xuan; Daniel R. Smith; Jones, Jonathan W.; Chapman, Matthew R.

    2006-01-01

    Amyloid formation is characterized by the conversion of soluble proteins into biochemically and structurally distinct fibers. Although amyloid formation is traditionally associated with diseases such as Alzheimer disease, a number of biologically functional amyloids have recently been described. Curli are amyloid fibers produced by Escherichia coli that contribute to biofilm formation and other important physiological processes. We characterized the polymerization properties of the major curl...

  7. 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...

  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...... 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...

  9. Role of serum amyloid P component in immune clearance

    International Nuclear Information System (INIS)

    In order to clarify the mechanism of interaction of serum amyloid P component (SAP) with complement, the interaction of SAP with Clq was studied. It is known that SAP binds Sepharose 4B in the presence of calcium. 125I-Clq was retained on the Sepharose when purified 125I-Clq was incubated with SAP prior to affinity chromatography on Sepharose. In the absence of SAP, the 125I-Clq was not retained. To further examine the interaction of SAP with Clq, SAP was incubated at varying ratios with Clq. These mixtures were examined via crossed immunoelectro-immunoelectrophoresis against goat anti-SAP. A change in the electrophoretic behavior of SAP was observed in the presence of Clq. It was found that SAP interacted with the collagen-like stem of Clq. In these studies, 125I-SAP was incubated with pepsin digests of Clq in a microtitre solid-phase binding assay. In addition, a microtitre solid-phase binding assay was utilized in order to investigate the possible binding of SAP with IgG. The ability of SAP activate complement as detected by C3 conversion was studied. It was found that SAP activated complement to a limited extent in normal human serum but caused extensive C3 conversion when serum from an individual with decreased levels of Cl inhibitor was used. Furthermore, the action of the complement pathway by SAP in the latter serum was reversed by the addition of exogenous Cl inhibitor, indicating that SAP has the ability to play a role in the regulation of complement via the classical pathway

  10. 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...

  11. 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.

  12. Serum α-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 α-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 μg/mL, respectively), compared with those in healthy cats (median, 269.85 and 0.10 μg/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

  13. Characterization of the circulating serum amyloid A in bottlenose dolphins.

    Science.gov (United States)

    Segawa, Takao; Otsuka, Toru; Itou, Takuya; Suzuki, Miwa; Karatani, Nana; Sakai, Takeo

    2013-04-15

    Several isoforms of serum amyloid A (SAA) have been identified so far and because the plasma concentration of it increases dramatically, it is used as an indicator of inflammation in animals. In many terrestrial mammals, the circulating isoforms are SAA1 and SAA2, which are synthesized in the liver. Extra-hepatically synthesized SAA3, however, is a predominantly local SAA isoform with a characteristic N-terminal TFLK motif and a highly alkaline isoelectric point (pI). The aim of this study was to characterize the circulating SAA isoforms in bottlenose dolphins (dSAA) by determining the deduced amino acid sequence isolated from liver and the pI of plasma from healthy dolphins and those with inflammation. The deduced amino acid sequences of dSAA showed characteristics of SAA3 with an N-terminal TFLK motif, a predicted alkaline pI and were phylogenetically clustered with the SAA3 group rather than the SAA1 and SAA2 groups. Various tissues contained dSAA mRNA with the highest levels being detected in the liver. Isoelectric focusing and western blot analysis showed that one highly alkaline SAA was markedly detected in plasma obtained from dolphins affected by inflammation. These results suggest that, unlike other mammals, the circulating SAA in dolphins exhibits SAA3 properties, as is the case in pigs. PMID:23333194

  14. Serum amyloid A impairs the antiinflammatory properties of HDL.

    Science.gov (United States)

    Han, Chang Yeop; Tang, Chongren; Guevara, Myriam E; Wei, Hao; Wietecha, Tomasz; Shao, Baohai; Subramanian, Savitha; Omer, Mohamed; Wang, Shari; O'Brien, Kevin D; Marcovina, Santica M; Wight, Thomas N; Vaisar, Tomas; de Beer, Maria C; de Beer, Frederick C; Osborne, William R; Elkon, Keith B; Chait, Alan

    2016-01-01

    HDL from healthy humans and lean mice inhibits palmitate-induced adipocyte inflammation; however, the effect of the inflammatory state on the functional properties of HDL on adipocytes is unknown. Here, we found that HDL from mice injected with AgNO3 fails to inhibit palmitate-induced inflammation and reduces cholesterol efflux from 3T3-L1 adipocytes. Moreover, HDL isolated from obese mice with moderate inflammation and humans with systemic lupus erythematosus had similar effects. Since serum amyloid A (SAA) concentrations in HDL increase with inflammation, we investigated whether elevated SAA is a causal factor in HDL dysfunction. HDL from AgNO3-injected mice lacking Saa1.1 and Saa2.1 exhibited a partial restoration of antiinflammatory and cholesterol efflux properties in adipocytes. Conversely, incorporation of SAA into HDL preparations reduced antiinflammatory properties but not to the same extent as HDL from AgNO3-injected mice. SAA-enriched HDL colocalized with cell surface-associated extracellular matrix (ECM) of adipocytes, suggesting impaired access to the plasma membrane. Enzymatic digestion of proteoglycans in the ECM restored the ability of SAA-containing HDL to inhibit palmitate-induced inflammation and cholesterol efflux. Collectively, these findings indicate that inflammation results in a loss of the antiinflammatory properties of HDL on adipocytes, which appears to partially result from the SAA component of HDL binding to cell-surface proteoglycans, thereby preventing access of HDL to the plasma membrane. PMID:26642365

  15. 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.

  16. 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. ...

  17. 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. 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...

  18. 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.

  19. 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-...

  20. 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

  1. 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...

  2. Alzheimer's disease amyloid precursor protein and amyloid beta peptides are key regulators of brain lipid composition

    OpenAIRE

    Tobias Hartmann

    2010-01-01

    Cholesterol has received special attention in AD, because it influences Aß (amyloid – beta) production, epidemiological studies show a clear correlation between high cholesterol and increased AD risk and because some cholesterol lowering drugs correlate with a reduced risk for dementia. Aß is a proteolytic processing product generated from the amyloid precursor protein APP. APP processing is part of a sensor system that responds to alterations in the lipid composition of ...

  3. 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...

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

    OpenAIRE

    Veszelka, Szilvia; Laszy, Judit; Pázmány, Tamás; Németh, László; 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...

  5. 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.

  6. 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 ...

  7. 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...

  8. Serum amyloid A and haptoglobin levels in crossbred cows with endometritis following different therapy

    Directory of Open Access Journals (Sweden)

    S. S. Biswal

    2014-12-01

    Full Text Available Aim: To determine the serum variations of two major acute phase proteins, serum amyloid A (SAA and haptoglobin (Hp levels in crossbred endometritis cows following pre and post immunomodulation therapy. Materials and Methods: 21 endometritis cows were randomly assigned to three groups (n=7 and treated with three different immunomodulators while seven healthy cows served as control. Uterine flushing collected from all animals was subjected to bacteriological study and serum samples were analyzed for SAA and Hp by sandwich ELISA method. Results: Escherichia coli was most prevalent Gram-negative bacteria (6.02 × 106 CFU/ml while Staphylococcus (0.86 × 106 CFU/ml and Streptococcus (0.52 × 106 CFU/ml were most predominant Gram-positive species isolated from uterine flushing. The pre-treatment SAA values (?g/ml varied significantly (p<0.01 between the treatment groups whereas no difference was observed in post-treatment groups. No significant difference (p<0.01 was observed for Hp values between the treatment groups, but the mean SAA (?g/ml and Hp (?g/ml levels were significantly (p<0.01 higher in pre-treatment when compared to post-treatment within the groups. Conclusion: In the diagnosis and monitoring of bovine endometritis, both SAA and Hp might serve as reliable biomarkers.

  9. A brief exposure to tryptase or thrombin potentiates fibrocyte differentiation in the presence of serum or serum amyloid p.

    Science.gov (United States)

    White, Michael J V; Galvis-Carvajal, Elkin; Gomer, Richard H

    2015-01-01

    A key question in both wound healing and fibrosis is the trigger for the initial formation of scar tissue. To help form scar tissue, circulating monocytes enter the tissue and differentiate into fibroblast-like cells called fibrocytes, but fibrocyte differentiation is strongly inhibited by the plasma protein serum amyloid P (SAP), and healthy tissues contain very few fibrocytes. In wounds and fibrotic lesions, mast cells degranulate to release tryptase, and thrombin mediates blood clotting in early wounds. Tryptase and thrombin are upregulated in wound healing and fibrotic lesions, and inhibition of these proteases attenuates fibrosis. We report that tryptase and thrombin potentiate human fibrocyte differentiation at biologically relevant concentrations and exposure times, even in the presence of concentrations of serum and SAP that normally completely inhibit fibrocyte differentiation. Fibrocyte potentiation by thrombin and tryptase is mediated by protease-activated receptors 1 and 2, respectively. Together, these results suggest that tryptase and thrombin may be an initial trigger to override SAP inhibition of fibrocyte differentiation to initiate scar tissue formation. PMID:25429068

  10. 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

  11. 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.

  12. Serum Amyloid A Induces Toll-Like Receptor 2-Dependent Inflammatory Cytokine Expression and Atrophy in C2C12 Skeletal Muscle Myotubes

    OpenAIRE

    Passey, Samantha L.; Bozinovski, Steven; Vlahos, Ross; Anderson, Gary P; Hansen, Michelle J.

    2016-01-01

    Background Skeletal muscle wasting is an important comorbidity of Chronic Obstructive Pulmonary Disease (COPD) and is strongly correlated with morbidity and mortality. Patients who experience frequent acute exacerbations of COPD (AECOPD) have more severe muscle wasting and reduced recovery of muscle mass and function after each exacerbation. Serum levels of the pro-inflammatory acute phase protein Serum Amyloid A (SAA) can rise more than 1000-fold in AECOPD and are predictively correlated wit...

  13. Amyloid Precursor Protein Processing in Alzheimer’s Disease

    OpenAIRE

    Adwait BHADBHADE; Davis Weizhong CHENG

    2012-01-01

    How to Cite this Article: Bhadbhade A, Cheng DW. Amyloid Precursor Protein Processing in Alzheimer’s Disease. Iranian Journal of Child Neurology2012;6(1):1-5.Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and a leading cause of dementia. The AD is characterized by presence of intraneuronal tangles and extracellular plaques in the brain. The plaques are composed of dense and mostly insoluble deposits of amyloid beta peptide (Aβ), formed by sequential cleavage of the Amylo...

  14. 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...

  15. 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

  16. 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.

  17. 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.

    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....

  18. 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 

  19. The localization and differential expression of Serum Amyloid A in bovine liver and adipose tissue depots.

    Science.gov (United States)

    Ceciliani, Fabrizio; Soler, Laura; Grilli, Guido; Marques, Andreia T; Giudice, Chiara; Lecchi, Cristina

    2015-11-15

    In this article the localization of the acute phase protein Serum Amyloid A (SAA) in different depots of bovine adipose tissue (AT) and liver is reported. Quantitative (Real Time) PCR was paired to immunohistochemistry after the production of a specific polyclonal antibody. SAA's mRNA was found in all analyzed AT depots included in the present study, the AT located in the withers being the major source of SAA mRNA. A polyclonal antibody was raised against bovine SAA and was used to validate gene expression analyses. Western Blotting confirmed that SAA is present in all the seven adipose tissue depots include in the present experiment. Anti-SAA polyclonal antibody also stained diffusely adipocytes. In liver, intracytoplasmic immunolabeling was observed in hepatocytes. Staining was generally mild and not diffuse: negative hepatocytes were intermixed with positive ones. A positive intracytoplasmic immunostaining was occasionally observed in endothelial cells lining small blood vessels within AT septa and liver parenchyma. Our data confirm that bovine AT may provide an important source of SAA in healthy subjects. It remains to be determined which is the contribution of AT in the serum concentration of SAA. PMID:26319890

  20. 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.

  1. 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...

  2. 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...

  3. Protein Crystal Serum Albumin

    Science.gov (United States)

    1998-01-01

    As the most abundant protein in the circulatory system albumin contributes 80% to colloid osmotic blood pressure. Albumin is also chiefly responsible for the maintenance of blood pH. It is located in every tissue and bodily secretion, with extracellular protein comprising 60% of total albumin. Perhaps the most outstanding property of albumin is its ability to bind reversibly to an incredible variety of ligands. It is widely accepted in the pharmaceutical industry that the overall distribution, metabolism, and efficiency of many drugs are rendered ineffective because of their unusually high affinity for this abundant protein. An understanding of the chemistry of the various classes of pharmaceutical interactions with albumin can suggest new approaches to drug therapy and design. Principal Investigator: Dan Carter/New Century Pharmaceuticals

  4. Serum protein binding of propylthiouracil.

    OpenAIRE

    Kampmann, J P; Mølholm Hansen, J E

    1983-01-01

    Serum protein binding of propylthiouracil (PTU) was measured by ultrafiltration in healthy and hyperthyroid patients. The serum protein binding in 12 euthyroid subjects was 76.2 +/- 1.2% (mean +/- s.d.), not significantly different from the values in 10 hyperthyroid patients: 76.6 +/- 1.3% Binding was unaffected by incubation time and temperatures between 25 and 37 degrees C, but increased from 76.5 to 79.1% when pH changed from 7.4 to 7.9. PTU is predominantly bound to albumin with two class...

  5. 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...

  6. 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...

  7. 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

  8. Amyloid formation and inhibition of an all-beta protein: A study on fungal polygalacturonase

    Science.gov (United States)

    Chinisaz, Maryam; Ghasemi, Atiyeh; Larijani, Bagher; Ebrahim-Habibi, Azadeh

    2014-02-01

    Theoretically, all proteins can adopt the nanofibrillar structures known as amyloid, which contain cross-beta structures. The all-beta folded proteins are particularly interesting in this regard, since they appear to be naturally more predisposed toward this structural arrangement. In this study, methanol has been used to drive the beta-helix protein polygalacturonase (PG), toward amyloid fibril formation. Congo red absorbance, thioflavin T fluorescence, circular dichroism (CD) and transmission electron microscopy have been used to characterize this process. Similar to other all-beta proteins, PG shows a non-cooperative fibrillation mechanism, but the structural changes that are monitored by CD indicate a different pattern. Furthermore, several compounds containing aromatic components were tested as potential inhibitors of amyloid formation. Another protein predominantly composed of alpha-helices (human serum albumin) was also targeted by these ligands, in order to get an insight into their potential anti-aggregation property toward structurally different proteins. Among tested compounds, silibinin and chlorpropamide were able to considerably affect both proteins fibrillation process.

  9. 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

  10. 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

  11. Localized and efficient curli nucleation requires the chaperone-like amyloid assembly protein CsgF

    OpenAIRE

    Nenninger, Ashley A.; Robinson, Lloyd S.; Hultgren, Scott J.

    2009-01-01

    Elucidation of the early events in amyloidogenesis is key to understanding the pathology of, and developing therapies for, amyloid diseases. Critical informants about these early events are amyloid assembly proteins that facilitate the transition from monomer to amyloid fiber. Curli are a functional amyloid whose in vivo polymerization requires a dedicated nucleator protein, CsgB, and an assembly protein, CsgF. Here we demonstrate that without CsgF, curli subunits are released from the cell i...

  12. Monoclonal antibodies to amyloid subunit proteins for in vivo radioimmunodetection of amyloid diseases

    International Nuclear Information System (INIS)

    Amyloid fibrils of systemic amyloidosis are low molecular weight subunit proteins with poor immunogenicity and a tendency to polymerize. Antibodies to these proteins are useful for the detection of amyloid deposits in-situ. The extracellular location of amyloid deposits and proximity to congophilic angiopathy suggest the potential of labeled monocional antibodies (MAb) for in vivo radioimmunodetection. The authors tested feasibility of this approach using two rat MAbs to mouse AA protein in casein-induced amyloidosis, a model system for human secondary amyloidosis. The antibodies were labeled with I-125, I-123, and In-111 with good specificity retention. Amyloidotic mice were pretreated with 50 ?g colchicine ip 3 hr before receiving radioiodinated MAb via the tall vein. Controls included injection of MAb to normal mice and of labeled polyclonal normal rat IgG (pIg) into amyloidotic and control mice. Blood clearance of MAb was faster in amyloidotic than control groups. Fractionation studies showed that both MAb and pIg were uncomplexed. Studies up to 96 hr showed specific and high uptake at sites of amyloid deposition (saline perfused liver, spleen, kidney. Specific localization was confirmed by whole body autoradiography (I-125, 20 ?Ci/animal; 50 ?g MAb) and by external imaging (I-123, 200 ?Ci/animal, 10-15 ?g MAb) of amyloidotic mice studied at 4-72 hr. Amyloidotic animals showed perifollicular localization in spleen, periportal in liver, and glomerular in kidney; scans of controls showed diffuse early washout. These results document the feasibility of using MAbs to fibril subunit proteins for the in vivo detection and therapy of amyloidosis

  13. 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

  14. Distinct Fc? receptors mediate the effect of serum amyloid p on neutrophil adhesion and fibrocyte differentiation.

    Science.gov (United States)

    Cox, Nehemiah; Pilling, Darrell; Gomer, Richard H

    2014-08-15

    The plasma protein serum amyloid P (SAP) reduces neutrophil adhesion, inhibits the differentiation of monocytes into fibroblast-like cells called fibrocytes, and promotes phagocytosis of cell debris by macrophages. Together, these effects of SAP reduce key aspects of inflammation and fibrosis, and SAP injections improve lung function in pulmonary fibrosis patients. SAP functions are mediated, in part, by Fc?Rs, but the contribution of each Fc?R is not fully understood. We found that aa Q55 and E126 in human SAP affect human fibrocyte differentiation and SAP binding to Fc?RI. E126, K130, and Q128 affect neutrophil adhesion and SAP affinity for Fc?RIIa. Q128 also affects phagocytosis by macrophages and SAP affinity for Fc?RI. All the identified functionally significant amino acids in SAP form a binding site that is distinct from the previously described SAP-Fc?RIIa binding site. Blocking Fc?RI with an IgG-blocking Ab reduces the SAP effect on fibrocyte differentiation, and ligating Fc?RIIa with Abs reduces neutrophil adhesion. Together, these results suggest that SAP binds to Fc?RI on monocytes to inhibit fibrocyte differentiation, and binds to Fc?RIIa on neutrophils to reduce neutrophil adhesion. PMID:25024390

  15. Persistent lung inflammation and fibrosis in serum amyloid P component (APCs-/-) knockout mice.

    Science.gov (United States)

    Pilling, Darrell; Gomer, Richard H

    2014-01-01

    Fibrosing diseases, such as pulmonary fibrosis, cardiac fibrosis, myelofibrosis, liver fibrosis, and renal fibrosis are chronic and debilitating conditions and are an increasing burden for the healthcare system. Fibrosis involves the accumulation and differentiation of many immune cells, including macrophages and fibroblast-like cells called fibrocytes. The plasma protein serum amyloid P component (SAP; also known as pentraxin-2, PTX2) inhibits fibrocyte differentiation in vitro, and injections of SAP inhibit fibrosis in vivo. SAP also promotes the formation of immuno-regulatory Mreg macrophages. To elucidate the endogenous function of SAP, we used bleomycin aspiration to induce pulmonary inflammation and fibrosis in mice lacking SAP. Compared to wildtype C57BL/6 mice, we find that in Apcs-/- "SAP knock-out" mice, bleomycin induces a more persistent inflammatory response and increased fibrosis. In both C57BL/6 and Apcs-/- mice, injections of exogenous SAP reduce the accumulation of inflammatory macrophages and prevent fibrosis. The types of inflammatory cells present in the lungs following bleomycin-aspiration appear similar between C57BL/6 and Apcs-/- mice, suggesting that the initial immune response is normal in the Apcs-/- mice, and that a key endogenous function of SAP is to promote the resolution of inflammation and fibrosis. PMID:24695531

  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. Disruption of Amyloid Prion Protein Aggregates by Cationic Pyridylphenylene Dendrimers.

    Science.gov (United States)

    Sorokina, Svetlana A; Stroylova, Yulia Yu; Shifrina, Zinaida B; Muronetz, Vladimir I

    2016-02-01

    Disruption of amyloid protein aggregates is one of the potential therapies for treatment of neurodegenerative disorders such as prion diseases. Here, for the first time we report that pH-independent cationic pyridylphenylene dendrimers are able to disrupt amyloid protein aggregates at physiological pH as exemplified by inclusion bodies of ovine prion protein. The results show that exposure of inclusion bodies to the dendrimers leads to its partial disaggregation and release of the nanosize protein-dendrimer complexes. The complexes were characterized by SDS PAGE, DLS, and Western blotting methods. Thioflavin T fluorescence clearly demonstrated a decrease of amyloidogenic capability of the prion protein upon exposure to the dendrimers. The complexes formed are stable and do not show further aggregation. PMID:26445143

  18. Amyloid Precursor Protein Processing in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Adwait BHADBHADE

    2012-03-01

    Full Text Available How to Cite this Article: Bhadbhade A, Cheng DW. Amyloid Precursor Protein Processing in Alzheimer’s Disease. Iranian Journal of Child Neurology2012;6(1:1-5.Alzheimer’s disease (AD is a progressive neurodegenerative disorder and a leading cause of dementia. The AD is characterized by presence of intraneuronal tangles and extracellular plaques in the brain. The plaques are composed of dense and mostly insoluble deposits of amyloid beta peptide (A?, formed by sequential cleavage of the Amyloid Precursor Protein (APP, by two pathways amyloidogenic and non-amyloidogenic. Tangles are composed of paired helical fragments, which aggregate to form, microtubular protein tau. Although A? plaques are established to be the cause of the disease, there exist genetic factors and other pathological identifications in addition to these which are an integral part of the disease. This article gives an overview into the mechanism of APP action, genetic factors and other pathological identifications contributing to Alzheimer’s disease formation.References Brookmeyer R, Gray S, Kawas C. Projections of Alzheimer’s disease in the United States and the public health impact of delaying disease onset. American Journal of Public Health 1998;88(9:1337. Hebert LE, Scherr PA, Bienias JL, Bennett DA, Evans DA. Alzheimer disease in the US population. Arch Neurol 2003;60(8:1119-22. Möller HJ, Graeber M. The case described by Alois Alzheimer in 1911. European Archives of Psychiatry and Clinical Neuroscience 1998:248(3:111-122. Selkoe D J. (2002. Deciphering the genesis and fate of amyloid beta-protein yields novel therapies for Alzheimer disease. J Clinic Investigat 2002;110(10: 1375-82. Wolfe MS. Tau mutations in neurodegenerative diseases. J Biolog Chem 2009;284(10:6021. Selkoe DJ. Alzheimer’s disease: genes, proteins, and therapy. Physiological reviews 2001;81(2:741. Selkoe DJ. The cell biology of [beta]-amyloid precursor protein and presenilin in Alzheimer’s disease. Trends in Cell Biology 1998;8(11:447-453. Thinakaran G, Koo EH. Amyloid precursor protein trafficking, processing, and function. Journal of Biological Chemistry 2008;283(44:29615. Zhang YW, Thompson R, Zhang H, Xu H. APP processing in Alzheimer’s disease. Mol Brain 2011;4:3. doi: 1756- 6606-4-3 [pii] 10.1186/1756-6606-4-3. Nunan J, Small DH. Regulation of APP cleavage by ?-,?- and ?-secretases. J Biolog Chem 2000:483(1:6-10. Pearson HA, Peers C. Physiological roles for amyloid peptides. J Physiology 2006;575(1:5-10. Wang Y, Ha Y. The X-ray structure of an antiparallel dimer of the human amyloid precursor protein E2 domain. Molecular Cell 2004;15(3:343-353. Quitschke WW, Goldgaber D. The amyloid b-protein precursor promoter. Journal Biolog Chem 1992;267(24:17362-17368. Vostrov AA, Taheny MJ, Izkhakov N, Quitschke WW. A nuclear factor-binding domain in the 5’-untranslated region of the amyloid precursor protein promoter: implications for the regulation of gene expression. BMC Research Notes 2010;3:4. Ghosala K,Vogta D, Lianga M, Shenb Y, Lamba BT, Sanjay W, Pimplikara SW. Alzheimer’s disease-like pathological features in transgenic mice expressing the APP intracellular domain. Proceedings of National Academy of Sciences 2009;106(43:18367-77.  

  19. 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...

  20. 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....

  1. 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...

  2. 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

  3. 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

  4. AMYPdb: A database dedicated to amyloid precursor proteins

    Directory of Open Access Journals (Sweden)

    Delamarche Christian

    2008-06-01

    Full Text Available Abstract Background Misfolding and aggregation of proteins into ordered fibrillar structures is associated with a number of severe pathologies, including Alzheimer's disease, prion diseases, and type II diabetes. The rapid accumulation of knowledge about the sequences and structures of these proteins allows using of in silico methods to investigate the molecular mechanisms of their abnormal conformational changes and assembly. However, such an approach requires the collection of accurate data, which are inconveniently dispersed among several generalist databases. Results We therefore created a free online knowledge database (AMYPdb dedicated to amyloid precursor proteins and we have performed large scale sequence analysis of the included data. Currently, AMYPdb integrates data on 31 families, including 1,705 proteins from nearly 600 organisms. It displays links to more than 2,300 bibliographic references and 1,200 3D-structures. A Wiki system is available to insert data into the database, providing a sharing and collaboration environment. We generated and analyzed 3,621 amino acid sequence patterns, reporting highly specific patterns for each amyloid family, along with patterns likely to be involved in protein misfolding and aggregation. Conclusion AMYPdb is a comprehensive online database aiming at the centralization of bioinformatic data regarding all amyloid proteins and their precursors. Our sequence pattern discovery and analysis approach unveiled protein regions of significant interest. AMYPdb is freely accessible 1.

  5. Maldi-Tof /Tof-MS Reveals Elevated Serum Haptoglobin and Amyloid A in Behcet's Disease

    OpenAIRE

    Mao, L; Dong, H.; Yang, P; Zhou, H; X. Huang; Lin, X.; Kijlstra, A.

    2008-01-01

    Behcet¿s disease (BD) is a multisystemic autoimmune disease with unclear etiology and pathogenesis. To screen aberrant serum proteins in BD, serum samples were obtained from eight male BD patients with active uveitis and eight male healthy volunteers with informed consent. The serum samples from active BD patients and normal controls were pooled. Highly abundant serum proteins (albumin and IgG) were depleted from these two samples using an affinity capture based kit. The obtained samples were...

  6. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Rossmann, Christine [Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz (Austria); Windpassinger, Christian; Brunner, Daniela [Institute of Human Genetics, Medical University of Graz, Graz (Austria); Kovacevic, Alenka; Schweighofer, Natascha; Malli, Roland [Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz (Austria); Schuligoi, Rufina [Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Graz (Austria); Prokesch, Andreas [Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz (Austria); Institute of Biochemistry, Graz University of Technology, Graz (Austria); Kluve-Beckerman, Barbara [Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN (United States); Graier, Wolfgang F.; Kratky, Dagmar; Sattler, Wolfgang [Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz (Austria); Malle, Ernst, E-mail: ernst.malle@medunigraz.at [Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz (Austria)

    2014-08-08

    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.

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. LL-37 inhibits serum amyloid A-induced IL-8 production in human neutrophils

    OpenAIRE

    Lee, Ha Young; Kim, Sang Doo; SHIM, JAE WOONG; Lee, Sun Young; Yun, Jeanho; BAE, YOE-SIK

    2009-01-01

    Serum amyloid A (SAA) has been regarded as an important mediator of inflammatory responses. The effect of several formyl peptide receptor-like 1 (FPRL1) ligands on the production of IL-8 by SAA was investigated in human neutrophils. Among the ligands tested, LL-37 was found to specifically inhibit SAA-induced IL-8 production in transcriptional and post-transcriptional levels. Since SAA stimulated IL-8 production via ERK and p38 MAPK in human neutrophils, we tested the effect of LL-37 on SAA i...

  13. 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...

  14. Detection of serum amyloid-A concentration in the calf clinically diagnosed with pneumonia, enteritis and pneumoenteritis

    Directory of Open Access Journals (Sweden)

    Mustafa Kabu

    2016-02-01

    Full Text Available ABSTRACT: The aim of this study is to determine serum amyloid-A (SAA concentration in the cases of pneumonia, pneumoenteritis, and enteritis which are frequently encountered in calves in veterinary medicine. Although a great deal of experimental studies has been conducted in this field, studies on naturally infected calves are quite few. Eighty calves at the age of 0-6 months were used in the study and the calves were divided into four groups. Due to the clinical examination, the calves diagnosed with pneumonia (Group P; n=20, with pneumoenteritis (Group PE; n=20 and with enteritis (Group E; n=20 formed the disease group as the healthy ones formed the control (Group C; n=20 group. After the body temperatures of all calves were taken, blood samples were obtained from Jugular vein for haematological and biochemical measurements. As haematological, white blood cell (WBC, red blood cell (RBC, hemoglobin (Hb and hematocrit (Hct measurements were performed in Veterinary Hematology Analyzer. Serum amyloid-A (SAA, interleukin 1 (IL-1?, interleukin 6 (IL-6, tumor necrosis factor-? (TNF-? concentration measurements were carried out with ELISA reader by using commercial kits. Aspartate aminotransferase (AST, alanine aminotransferase (ALT, albumin (ALB, total bilirubin (T. Bil, total protein (TP, gamma glutamyltransferase (GGT, blood urea nitrogen (BUN concentration measurements were conducted in autoanalyzer by using commercial kits. In all disease groups (P, PE, and E body temperature, haematologic parameters (WBC, RBC, Hb and Hct, serum biochemical parameters (AST, ALT, ALB, T. Bil, TP, GGT and BUN, SAA concentration and serum concentrations of cytokines (IL-1?, IL-6 and TNF-? were determined to be higher in comparison to the control group (P<0.005. According to these findings, routine measurement of serum SAA concentration in veterinary medicine is considered to be beneficial in determining the severity of the disease, in selecting the proper treatment, in monitoring the applied treatment, and detecting subclinical diseases. In the light of these findings we acknowledge that routine measurements of serum SAA concentration from the moment the calves are diagnosed with pneumonia, enteritis and pneumoenteritis in veterinary medicine until the actual cause is determined (bacteria, virus, parasites, etc. would avail the clinician to, identify the severity of the disease, select the appropriate treatment and monitor the effectiveness of the treatment.

  15. Exosomal cellular prion protein drives fibrillization of amyloid beta and counteracts amyloid beta-mediated neurotoxicity.

    Science.gov (United States)

    Falker, Clemens; Hartmann, Alexander; Guett, Inga; Dohler, Frank; Altmeppen, Hermann; Betzel, Christian; Schubert, Robin; Thurm, Dana; Wegwitz, Florian; Joshi, Pooja; Verderio, Claudia; Krasemann, Susanne; Glatzel, Markus

    2016-04-01

    Alzheimer's disease is a common neurodegenerative, progressive, and fatal disorder. Generation and deposition of amyloid beta (Aβ) peptides associate with its pathogenesis and small soluble Aβ oligomers show the most pronounced neurotoxic effects and correlate with disease initiation and progression. Recent findings showed that Aβ oligomers bind to the cellular prion protein (PrP(C) ) eliciting neurotoxic effects. The role of exosomes, small extracellular vesicles of endosomal origin, in Alzheimer's disease is only poorly understood. Besides serving as disease biomarkers they may promote Aβ plaque formation, decrease Aβ-mediated synaptotoxicity, and enhance Aβ clearance. Here, we explore how exosomal PrP(C) connects to protective functions attributed to exosomes in Alzheimer's disease. To achieve this, we generated a mouse neuroblastoma PrP(C) knockout cell line using transcription activator-like effector nucleases. Using these, as well as SH-SY5Y human neuroblastoma cells, we show that PrP(C) is highly enriched on exosomes and that exosomes bind amyloid beta via PrP(C) . Exosomes showed highest binding affinity for dimeric, pentameric, and oligomeric Aβ species. Thioflavin T assays revealed that exosomal PrP(C) accelerates fibrillization of amyloid beta, thereby reducing neurotoxic effects imparted by oligomeric Aβ. Our study provides further evidence for a protective role of exosomes in Aβ-mediated neurodegeneration and highlights the importance of exosomal PrP(C) in molecular mechanisms of Alzheimer's disease. We show that the prion protein (PrP(C) ) on exosomes captures neurotoxic species of amyloid beta (Aβ) promoting its fibrillization. Our study provides evidence for a protective role of exosomes in Alzheimer`s disease and suggests that, depending on its membrane topology, PrP(C) holds a dual function: when expressed at the neuronal surface it acts as receptor for Aβ leading to neurotoxic signaling, whereas it detoxifies Aβ when present on exosomes. This provides further support for key roles of PrP(C) in Alzheimer's disease. Read the Editorial Highlight for this article on page 9. Cover Image for this issue: doi: 10.1111/jnc.13312. PMID:26710111

  16. Alzheimer's disease amyloid precursor protein and amyloid beta peptides are key regulators of brain lipid composition

    Directory of Open Access Journals (Sweden)

    Tobias Hartmann

    2010-05-01

    Full Text Available Cholesterol has received special attention in AD, because it influences Aß (amyloid – beta production, epidemiological studies show a clear correlation between high cholesterol and increased AD risk and because some cholesterol lowering drugs correlate with a reduced risk for dementia. Aß is a proteolytic processing product generated from the amyloid precursor protein APP. APP processing is part of a sensor system that responds to alterations in the lipid composition of cellular membranes. This system is highly sensitive to alterations in certain lipids, whereas it is entirely insensitive to others. E.g. cholesterol strongly activates amyloidogenic APP processing, resulting in increased Aß release. Phosphatidylethanolamins however, typically don’t affect APP processing. The increased Aß production and other APP processing events caused by cholesterol, trigger several regulatory feedback actions, including the activation and inhibition of key lipid metabolism enzymes, that together aim to reset the brains lipid homeostasis. Although cholesterol is the best-studied brain lipid in AD, many other lipids are involved in the Aß-lipid regulatory system and some of these other lipids exceed the cholesterol effect on Aß production greatly. Thus far we were able to identify 5 lipid classes, involved in Aß regulation. One factor that recently gathered more attention are fatty acids. Most fatty acids have no or only marginal effects on amyloid metabolism, but some significantly increase or decrease Aß generation. Especially interesting are the Aß reducing abilities of some omega-3 polyunsaturated fatty acids, especially the DHA mentioned above and the EPA. These findings add to a rising number of results that help to understand the significant impact the lipid metabolism has in Alzheimer’s disease. The future challenge will be to decipher the molecular pathways which link neurodegeneration and lipids in Alzheimer’s disease and to use develop save and effective prevention and early therapy of Alzheimer’s disease.

  17. 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.

  18. 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...

  19. 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...

  20. Antibody-bound amyloid precursor protein upregulates ornithine decarboxylase expression

    DEFF Research Database (Denmark)

    Nilsson, Tatjana; Malkiewicz, Katarzyna; Gabrielsson, Maria; Folkesson, Ronnie; Winblad, Bengt; Benedikz, Eirikur

    2006-01-01

    Alzheimer's disease is a neurodegenerative disorder characterised by extracellular accumulation of the Abeta peptide, derived from the amyloid precursor protein (APP). The function of APP as a cell surface receptor was examined by ligand-mimicking using an antibody against the APP extracellular...... domain. Alterations in gene expression evoked by antibody-bound APP were analysed using human pathway-finder gene arrays and the largest change in expression levels was found for ornithine decarboxylase (ODC). These results were confirmed by Western blotting which showed even higher upregulation on the...... signalling events. This study shows that antibody-bound APP leads to altered gene expression that may be relevant to AD....

  1. 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.

  2. 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

  3. The amyloid precursor protein and postnatal neurogenesis/neuroregeneration

    International Nuclear Information System (INIS)

    The amyloid precursor protein (APP) is the source of amyloid-beta (A?) peptide, produced via its sequential cleavage ?- and ?-secretases. Various biophysical forms of A? (and the mutations of APP which results in their elevated levels) have been implicated in the etiology and early onset of Alzheimer's disease. APP's evolutionary conservation and the existence of APP-like isoforms (APLP1 and APLP2) which lack the A? sequence, however, suggest that these might have important physiological functions that are unrelated to A? production. Soluble N-terminal fragments of APP have been known to be neuroprotective, and the interaction of its cytoplasmic C-terminus with a myriad of proteins associates it with diverse processes such as axonal transport and transcriptional regulation. The notion for an essential postnatal function of APP has been demonstrated genetically, as mice deficient in both APP and APLP2 or all three APP isoforms exhibit early postnatal lethality and neuroanatomical abnormalities. Recent findings have also brought to light two possible functions of the APP family in Brain-regulation of neural progenitor cell proliferation and axonal outgrowth after injury. Interestingly, these two apparently related neurogenic/neuroregenerative functions of APP involve two separate domains of the molecule

  4. 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

  5. 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...

  6. 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...

  7. 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...

  8. 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.

  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 a...

  10. 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

  11. 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

    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...

  12. 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...

  13. 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...

  14. Proteomic evaluation of sheep serum proteins

    Directory of Open Access Journals (Sweden)

    Chiaradia Elisabetta

    2012-05-01

    Full Text Available Abstract Background The applications of proteomic strategies to ovine medicine remain limited. The definition of serum proteome may be a good tool to identify useful protein biomarkers for recognising sub-clinical conditions and overt disease in sheep. Findings from bovine species are often directly translated for use in ovine medicine. In order to characterize normal protein patterns and improve knowledge of molecular species-specific characteristics, we generated a two-dimensional reference map of sheep serum. The possible application of this approach was tested by analysing serum protein patterns in ewes with mild broncho-pulmonary disease, which is very common in sheep and in the peripartum period which is a stressful time, with a high incidence of infectious and parasitic diseases. Results This study generated the first reference 2-DE maps of sheep serum. Overall, 250 protein spots were analyzed, and 138 identified. Compared with healthy sheep, serum protein profiles of animals with rhino-tracheo-bronchitis showed a significant decrease in protein spots identified as transthyretin, apolipoprotein A1 and a significant increase in spots identified as haptoglobin, endopin 1b and alpha1B glycoprotein. In the peripartum period, haptoglobin, alpha-1-acid glycoprotein, apolipoprotein A1 levels rose, while transthyretin content dropped. Conclusions This study describes applications of proteomics in putative biomarker discovery for early diagnosis as well as for monitoring the physiological and metabolic situations critical for ovine welfare.

  15. 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...

  16. 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

  17. 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...

  18. 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...

  19. 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

  20. 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.

  1. 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

  2. The role of protein hydrophobicity in conformation change and self-assembly into large amyloid fibers.

    Science.gov (United States)

    Ridgley, Devin M; Claunch, Elizabeth C; Lee, Parker W; Barone, Justin R

    2014-04-14

    It has been found that a short hydrophobic "template" peptide and a larger ?-helical "adder" protein cooperatively self-assemble into micrometer sized amyloid fibers. Here, a common template of trypsin hydrolyzed gliadin is combined with six adder proteins (?-casein, ?-lactalbumin, amylase, hemoglobin, insulin, and myoglobin) to determine what properties of the adder protein drive amyloid self-assembly. Utilizing Fourier Transform-Infrared (FT-IR) spectroscopy, the Amide I absorbance reveals that the observed decrease in ?-helix with time is approximately equal to the increase in high strand density ?-sheet, which is indicative of amyloid formation. The results show that the hydrophobic moment is a good predictor of conformation change but the fraction of aliphatic amino acids within the ?-helices is a better predictor. Upon drying, the protein mixtures form large amyloid fibers. The fiber twist is dependent on the aliphatic index and molecular weight of the adder protein. Here we demonstrate that it is possible to predict the propensity of an adder protein to unfold into an amyloid structure and to predict the fiber morphology, both from adder protein molecular features, which can be applied to the pragmatic engineering of large amyloid fibers. PMID:24601565

  3. Amyloid-? nanotubes are associated with prion protein-dependent synaptotoxicity

    Science.gov (United States)

    Nicoll, Andrew J.; Panico, Silvia; Freir, Darragh B.; Wright, Daniel; Terry, Cassandra; Risse, Emmanuel; Herron, Caroline E.; O’Malley, Tiernan; Wadsworth, Jonathan D. F.; Farrow, Mark A.; Walsh, Dominic M.; Saibil, Helen R.; Collinge, John

    2013-01-01

    Growing evidence suggests water-soluble, non-fibrillar forms of amyloid-? protein (A?) have important roles in Alzheimer’s disease with toxicities mimicked by synthetic A?1–42. However, no defined toxic structures acting via specific receptors have been identified and roles of proposed receptors, such as prion protein (PrP), remain controversial. Here we quantify binding to PrP of A?1–42 after different durations of aggregation. We show PrP-binding and PrP-dependent inhibition of long-term potentiation (LTP) correlate with the presence of protofibrils. Globular oligomers bind less avidly to PrP and do not inhibit LTP, whereas fibrils inhibit LTP in a PrP-independent manner. That only certain transient A? assemblies cause PrP-dependent toxicity explains conflicting reports regarding the involvement of PrP in A?-induced impairments. We show that these protofibrils contain a defined nanotubular structure with a previously unidentified triple helical conformation. Blocking the formation of A? nanotubes or their interaction with PrP might have a role in treatment of Alzheimer’s disease. PMID:24022506

  4. 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...

  5. Single-Molecule Imaging of Individual Amyloid Protein Aggregates in Human Biofluids.

    Science.gov (United States)

    Horrocks, Mathew H; Lee, Steven F; Gandhi, Sonia; Magdalinou, Nadia K; Chen, Serene W; Devine, Michael J; Tosatto, Laura; Kjaergaard, Magnus; Beckwith, Joseph S; Zetterberg, Henrik; Iljina, Marija; Cremades, Nunilo; Dobson, Christopher M; Wood, Nicholas W; Klenerman, David

    2016-03-16

    The misfolding and aggregation of proteins into amyloid fibrils characterizes many neurodegenerative disorders such as Parkinson's and Alzheimer's diseases. We report here a method, termed SAVE (single aggregate visualization by enhancement) imaging, for the ultrasensitive detection of individual amyloid fibrils and oligomers using single-molecule fluorescence microscopy. We demonstrate that this method is able to detect the presence of amyloid aggregates of α-synuclein, tau, and amyloid-β. In addition, we show that aggregates can also be identified in human cerebrospinal fluid (CSF). Significantly, we see a twofold increase in the average aggregate concentration in CSF from Parkinson's disease patients compared to age-matched controls. Taken together, we conclude that this method provides an opportunity to characterize the structural nature of amyloid aggregates in a key biofluid, and therefore has the potential to study disease progression in both animal models and humans to enhance our understanding of neurodegenerative disorders. PMID:26800462

  6. 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.

  7. 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

  8. 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

  9. Neurotrophic effects of amyloid precursor protein peptide 165 in vitro.

    Science.gov (United States)

    Yao, Jie; Ma, Lina; Wang, Rong; Sheng, Shuli; Ji, Zhijuan; Zhang, Jingyan

    2016-01-01

    Diabetic encephalopathy is one of the risk factors for Alzheimer's disease. Our previous findings indicated that animals with diabetic encephalopathy exhibit learning and memory impairment in addition to hippocampal neurodegeneration, both of which are ameliorated with amyloid precursor protein (APP) 17-mer (APP17) peptide treatment. Although APP17 is neuroprotective, it is susceptible to enzymatic degradation. Derived from the active sequence structure of APP17, we have previously structurally transformed and modified several APP5-mer peptides (APP328-332 [RERMS], APP 5). We have developed seven different derivatives of APP5, including several analogs. Results from the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on human neuroblastoma SH-SY5Y cells in the present study showed that P165 was the most neuroprotective APP5 derivative. Furthermore, we tested the effects of APP5 and P165 on the number of cells and the release of lactate dehydrogenase. Western immunoblot analyses were also performed. The digestion rates of P165 and APP5 were determined by the pepsin digestion test. P165 resisted pepsin digestion significantly more than APP5. Therefore, P165 may be optimal for oral administration. Overall, these findings suggest that P165 may be a potential drug for the treatment of diabetic encephalopathy. PMID:26551064

  10. 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..

  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. 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...

  13. 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...

  14. 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.

  15. 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

  16. Recombinant human serum amyloid P in healthy volunteers and patients with pulmonary fibrosis.

    Science.gov (United States)

    Dillingh, M R; van den Blink, B; Moerland, M; van Dongen, M G J; Levi, M; Kleinjan, A; Wijsenbeek, M S; Lupher, M L; Harper, D M; Getsy, J A; Hoogsteden, H C; Burggraaf, J

    2013-12-01

    PRM-151, recombinant human Pentraxin-2 (PTX-2) also referred to as serum amyloid P (SAP), is under development for treatment of fibrosis. A First-in-Human (FIH) trial was performed to assess the safety, tolerability, and pharmacokinetics of single ascending intravenous doses of PRM-151 administered to healthy subjects, using a randomized, blinded, placebo controlled study design. Each cohort included three healthy subjects (PRM-151:placebo; 2:1). SAP levels were assessed using a validated ELISA method, non-discriminating between endogenous and exogenous SAP. At a dose level of 10 mg/kg, at which a physiologic plasma level of SAP was reached, two additional healthy volunteers and three pulmonary fibrosis (PF) patients were enrolled enabling comparison of the pharmacokinetic SAP profile between healthy volunteers and PF patients. In addition, the percentage of fibrocytes (CD45+/Procollagen-1+ cells) in whole blood samples was assessed to demonstrate biological activity of PRM-151 in the target population. PRM-151 administration was generally well tolerated. In two pulmonary fibrosis patients non-specific, transient skin reactions (urticaria and erythema) were observed. PRM-151 administration resulted in a 6-to 13-fold increase in mean baseline plasma SAP levels at dose levels of 5, 10, and 20 mg/kg. The estimated t1/2 of PRM-151 in healthy volunteers was 30 h. Pharmacokinetic profiles were comparable between healthy volunteers and PF patients. PRM-151 administration resulted in a 30-50% decrease in fibrocyte numbers 24 h post-dose. This suggests that administration of PRM-151 may be associated with a reduction of fibrocytes in PF patients, a population for which current pharmacotherapeutic options are limited. The pharmacological action of PRM-151 should be confirmed in future research. PMID:23380438

  17. Oxysterol-binding protein-1 (OSBP1 modulates processing and trafficking of the amyloid precursor protein

    Directory of Open Access Journals (Sweden)

    Seabrook Guy R

    2008-03-01

    Full Text Available Background Evidence from biochemical, epidemiological and genetic findings indicates that cholesterol levels are linked to amyloid-? (A? production and Alzheimer's disease (AD. Oxysterols, which are cholesterol-derived ligands of the liver X receptors (LXRs and oxysterol binding proteins, strongly regulate the processing of amyloid precursor protein (APP. Although LXRs have been studied extensively, little is known about the biology of oxysterol binding proteins. Oxysterol-binding protein 1 (OSBP1 is a member of a family of sterol-binding proteins with roles in lipid metabolism, regulation of secretory vesicle generation and signal transduction, and it is thought that these proteins may act as sterol sensors to control a variety of sterol-dependent cellular processes. Results We investigated whether OSBP1 was involved in regulating APP processing and found that overexpression of OSBP1 downregulated the amyloidogenic processing of APP, while OSBP1 knockdown had the opposite effect. In addition, we found that OSBP1 altered the trafficking of APP-Notch2 dimers by causing their accumulation in the Golgi, an effect that could be reversed by treating cells with OSBP1 ligand, 25-hydroxycholesterol. Conclusion These results suggest that OSBP1 could play a role in linking cholesterol metabolism with intracellular APP trafficking and A? production, and more importantly indicate that OSBP1 could provide an alternative target for A?-directed therapeutic.

  18. 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

  19. 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

  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.

    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.

  1. 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)

  2. 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)

  3. An Accessory Protein Required for Anchoring and Assembly of Amyloid Fibers in B. subtilis Biofilms

    OpenAIRE

    ROMERO, diego; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2011-01-01

    Cells within Bacillus subtilis biofilms are held in place by an extracellular matrix that contains cell-anchored amyloid fibers, composed of the amyloidogenic protein TasA. As biofilms age they disassemble because the cells release the amyloid fibers. This release appears to be the consequence of incorporation of D-tyrosine, D-leucine, D-tryptophan and D-methionine into the cell wall. Here, we characterize the in vivo roles of an accessory protein TapA (TasA anchoring/assembly protein; previo...

  4. ?-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 ...

  5. The Impairment of Macrophage-to-Feces Reverse Cholesterol Transport during Inflammation Does Not Depend on Serum Amyloid A

    OpenAIRE

    De Beer, Maria C; Wroblewski, Joanne M.; Noffsinger, Victoria P; Ailing Ji; Meyer, Jason M.; van der Westhuyzen, Deneys R.; de Beer, Frederick C; Webb, Nancy R.

    2013-01-01

    Studies suggest that inflammation impairs reverse cholesterol transport (RCT). We investigated whether serum amyloid A (SAA) contributes to this impairment using an established macrophage-to-feces RCT model. Wild-type (WT) mice and mice deficient in SAA1.1 and SAA2.1 (SAAKO) were injected intraperitoneally with 3H-cholesterol-labeled J774 macrophages 4?hr after administration of LPS or buffered saline. 3H-cholesterol in plasma 4?hr after macrophage injection was significantly reduced in both ...

  6. Amyloid precursor protein (APP) traffics from the cell surface via endosomes for amyloid ? (A?) production in the trans-Golgi network

    OpenAIRE

    Choy, Regina Wai-Yan; CHENG, ZHILIANG; Schekman, Randy

    2012-01-01

    Amyloid precursor protein (APP) is processed sequentially by the ?-site APP cleaving enzyme and ?-secretase to generate amyloid ? (A?) peptides, one of the hallmarks of Alzheimer’s disease. The intracellular location of A? production—endosomes or the trans-Golgi network (TGN)—remains uncertain. We investigated the role of different postendocytic trafficking events in A?40 production using an RNAi approach. Depletion of Hrs and Tsg101, acting early in the multivesicular body pathway, retained ...

  7. Dual amyloid domains promote differential functioning of the chaplin proteins during Streptomyces aerial morphogenesis

    OpenAIRE

    Capstick, David S.; Jomaa, Ahmad; Hanke, Chistopher; Ortega, Joaquin; Elliot, Marie A

    2011-01-01

    The chaplin proteins are functional amyloids found in the filamentous Streptomyces bacteria. These secreted proteins are required for the aerial development of Streptomyces coelicolor, and contribute to an intricate rodlet ultrastructure that decorates the surfaces of aerial hyphae and spores. S. coelicolor encodes eight chaplin proteins. Previous studies have revealed that only three of these proteins (ChpC, ChpE, and ChpH) are necessary for promoting aerial development, and of these three, ...

  8. 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)

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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...

  15. Serum protein changes after abdominal surgery.

    Science.gov (United States)

    Shakespeare, P G; Ball, A J; Spurr, E D

    1989-01-01

    Changes in the concentrations of 11 serum proteins following surgery for a variety of conditions have been investigated. Protein changes were analogous to those observed after injury or trauma, but showed differences in the detailed behaviour of the pattern of change. Marked increases in the concentrations of five acute-phase reactant proteins (APRP) were seen, with maximum concentrations usually being reached 2 days after surgery in patients who made an uncomplicated recovery from their operations. Considerable differences were observed between the patterns of change of APRP in patients who developed complications during recovery and in patients who made an uncomplicated recovery from surgery. Concentrations of C-reactive protein and alpha-1 antichymotrypsin (ACT) were much higher in the patients who developed complications, with ACT concentrations providing the clearest separation between the groups. The main factor influencing the changes in APRP during the recovery period appeared to be the development of sepsis. Preoperative concentrations of APRP had no prognostic value for identifying patients at risk of developing complications. The study suggests that the localisation of inflamed tissue involved in the disease processes may influence the detailed behaviour of the acute-phase reactant proteins. PMID:2472099

  16. 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...

  17. 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.

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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.

  3. Synthetic peptide homologous to β protein from Alzheimer's disease forms amyloid-like fibrils in vitro

    International Nuclear Information System (INIS)

    Progressive amyloid deposition in senile plaques and cortical blood vessels may play a central role in the pathogenesis of Alzheimer's disease. The authors have used x-ray diffraction and electron microscopy to study the molecular organization and morphology of macromolecular assemblies formed by three synthetic peptides homologous to β protein of brain amyloid: β-(1-28), residues 1-28 of the β protein; [Ala1-β-(1-28), β-(1-28) with alanine substituted for lysine at position 16; and β-(18-28), residues 18-28 of the β protein. β-(1-28) readily formed fibrils in vitro that were similar in ultrastructure to the in vivo amyloid and aggregated into large bundles resembling those of senile plaque cores. X-ray patterns from partially dried, oriented pellets showed a cross-β-conformation. [Ala16]β-(1-28) formed β-pleated sheet assemblies that were dissimilar to in vivo fibrils. The width of the 10-A spacing indicated stacks of about six sheets. Thus, substitution of the uncharged alanine for the positively charged lysine in the β-strand region enhances the packing of the sheets and dramatically alters the type of macromolecular aggregate formed. Β-(18-28) formed assemblies that had even a greater number of stacked sheets. The findings on these homologous synthetic assemblies help to define the specific sequence that is required to form Alzheimer's-type amyloid fibrils, thus providing an in vitro model of age-related cerebral amyloidogenesis

  4. 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 β-amyloid protein (Aβ 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 β-amyloid deposits in autopsy sections of the parietal and occipital cortex of an AD patient as compared with controls. Adding 10 μM 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 β-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.)

  5. 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...

  6. 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...

  7. Phagocytosis and LPS alter the maturation state of ?-amyloid precursor protein and induce different A? peptide release signatures in human mononuclear phagocytes

    Directory of Open Access Journals (Sweden)

    Kornhuber Johannes

    2010-10-01

    Full Text Available Abstract Background The classic neuritic ?-amyloid plaque of Alzheimer's disease (AD is typically associated with activated microglia and neuroinflammation. Similarly, cerebrovascular ?-amyloid (A? deposits are surrounded by perivascular macrophages. Both observations indicate a contribution of the mononuclear phagocyte system to the development of ?-amyloid. Methods Human CD14-positive mononuclear phagocytes were isolated from EDTA-anticoagulated blood by magnetic activated cell sorting. After a cultivation period of 72 hours in serum-free medium we assessed the protein levels of amyloid precursor protein (APP as well as the patterns and the amounts of released A? peptides by ELISA or one-dimensional and two-dimensional urea-based SDS-PAGE followed by western immunoblotting. Results We observed strong and significant increases in A? peptide release upon phagocytosis of acetylated low density lipoprotein (acLDL or polystyrene beads and also after activation of the CD14/TLR4 pathway by stimulation with LPS. The proportion of released N-terminally truncated A? variants was increased after stimulation with polystyrene beads and acLDL but not after stimulation with LPS. Furthermore, strong shifts in the proportions of single A?1-40 and A?2-40 variants were detected resulting in a stimulus-specific A? signature. The increased release of A? peptides was accompanied by elevated levels of full length APP in the cells. The maturation state of APP was correlated with the release of N-terminally truncated A? peptides. Conclusions These findings indicate that mononuclear phagocytes potentially contribute to the various N-truncated A? variants found in AD ?-amyloid plaques, especially under neuroinflammatory conditions.

  8. Hook proteins: association with Alzheimer pathology and regulatory role of hook3 in amyloid beta generation.

    Science.gov (United States)

    Herrmann, Lydia; Wiegmann, Caspar; Arsalan-Werner, Annika; Hilbrich, Isabel; Jäger, Carsten; Flach, Katharina; Suttkus, Anne; Lachmann, Ingolf; Arendt, Thomas; Holzer, Max

    2015-01-01

    Defects in intracellular transport are implicated in the pathogenesis of Alzheimer's disease (AD). Hook proteins are a family of cytoplasmic linker proteins that participate in endosomal transport. In this study we show that Hook1 and Hook3 are expressed in neurons while Hook2 is predominantly expressed in astrocytes. Furthermore, Hook proteins are associated with pathological hallmarks in AD; Hook1 and Hook3 are localized to tau aggregates and Hook2 to glial components within amyloid plaques. Additionally, the expression of Hook3 is reduced in AD. Modelling of Hook3 deficiency in cultured cells leads to slowing of endosomal transport and increases ?-amyloid production. We propose that Hook3 plays a role in pathogenic events exacerbating AD. PMID:25799409

  9. 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.

  10. 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...

  11. 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.

  12. 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.

  13. Extension of a protein docking algorithm to membranes and applications to amyloid precursor protein dimerization.

    Science.gov (United States)

    Viswanath, Shruthi; Dominguez, Laura; Foster, Leigh S; Straub, John E; Elber, Ron

    2015-12-01

    Novel adjustments are introduced to the docking algorithm, DOCK/PIERR, for the purpose of predicting structures of transmembrane protein complexes. Incorporating knowledge about the membrane environment is shown to significantly improve docking accuracy. The extended version of DOCK/PIERR is shown to perform comparably to other leading docking packages. This membrane version of DOCK/PIERR is applied to the prediction of coiled-coil homodimer structures of the transmembrane region of the C-terminal peptide of amyloid precursor protein (C99). Results from MD simulation of the C99 homodimer in POPC bilayer and docking are compared. Docking results are found to capture key aspects of the homodimer ensemble, including the existence of three topologically distinct conformers. Furthermore, the extended version of DOCK/PIERR is successful in capturing the effects of solvation in membrane and micelle. Specifically, DOCK/PIERR reproduces essential differences in the homodimer ensembles simulated in POPC bilayer and DPC micelle, where configurational entropy and surface curvature effects bias the handedness and topology of the homodimer ensemble. Proteins 2015; 83:2170-2185. © 2015 Wiley Periodicals, Inc. PMID:26404856

  14. 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

  15. 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

  16. The Effect of Different Types of Musculoskeletal Injuries on Blood Concentration of Serum Amyloid A in Thoroughbred Racehorses

    Science.gov (United States)

    Tur?o, Agnieszka; Cywi?ska, Anna; Czopowicz, Micha?; Witkowski, Lucjan; Nied?wied?, Artur; S?owikowska, Malwina; Borowicz, Hieronim; Ja?kiewicz, Anna; Winnicka, Anna

    2015-01-01

    Background Training-induced muscle, skeletal and joint trauma may result in acute phase response reflected by the changes in the blood concentration of serum amyloid A (SAA) in racehorses. It remains yet unclear if such systemic reaction could be triggered by sport injuries and what is the impact of different types of musculoskeletal trauma on SAA concentrations in racehorses. This study aimed to determine changes in the SAA blood concentration in racehorses with different types of injuries of musculoskeletal system. Materials and Methods The study involved 28 racehorses diagnosed after the race with bone fractures (n = 7), dorsal metacarpal disease (n = 11), joint trauma (n = 4) or tendon and muscle trauma (n = 6) and 28 healthy control racehorses. Serum samples were collected twice, between 1 and 4 days of the injury or succesful completion of the race. SAA concentration was measured using the commercial ELISA kit. Differences between mean SAA concentration in respective groups were analyzed using ANOVA and Tukey post-hoc test. Results Mean SAA concentration within the first 4 days of the injury of muscle and tendon was significantly higher than in bone fractures, dorsal metacarpal disease, joint trauma or in the healthy horses (p<0,001). There were no significant differences between the other groups. Conclusions Strain injuries of muscle and tendons can cause a moderate increase in SAA blood concentration in racehorses, reflecting the occurrence of the acute phase response. Similar reaction is not observed in the stress-related bone injuries. PMID:26466121

  17. The Impairment of Macrophage-to-Feces Reverse Cholesterol Transport during Inflammation Does Not Depend on Serum Amyloid A.

    Science.gov (United States)

    de Beer, Maria C; Wroblewski, Joanne M; Noffsinger, Victoria P; Ji, Ailing; Meyer, Jason M; van der Westhuyzen, Deneys R; de Beer, Frederick C; Webb, Nancy R

    2013-01-01

    Studies suggest that inflammation impairs reverse cholesterol transport (RCT). We investigated whether serum amyloid A (SAA) contributes to this impairment using an established macrophage-to-feces RCT model. Wild-type (WT) mice and mice deficient in SAA1.1 and SAA2.1 (SAAKO) were injected intraperitoneally with (3)H-cholesterol-labeled J774 macrophages 4?hr after administration of LPS or buffered saline. (3)H-cholesterol in plasma 4?hr after macrophage injection was significantly reduced in both WT and SAAKO mice injected with LPS, but this was not associated with a reduced capacity of serum from LPS-injected mice to promote macrophage cholesterol efflux in vitro. Hepatic accumulation of (3)H-cholesterol was unaltered in either WT or SAAKO mice by LPS treatment. Radioactivity present in bile and feces of LPS-injected WT mice 24?hr after macrophage injection was reduced by 36% (P mice, LPS did not significantly reduce macrophage-derived (3)H-cholesterol in bile, and fecal excretion was reduced by only 45% (P cholesterol-loaded allogeneic J774 cells, but not syngeneic bone-marrow-derived macrophages, transiently induced SAA in C57BL/6 mice. Our study confirms reports that acute inflammation impairs steps in the RCT pathway and establishes that SAA plays only a minor role in this impairment. PMID:23431457

  18. 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.

  19. 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

  20. 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

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. Peripheral biomarkers in Autism: secreted amyloid precursor protein-? as a probable key player in early diagnosis

    OpenAIRE

    Bailey, Antoinette R.; Giunta, Brian N.; Obregon, Demian; Nikolic, William V; Tian, Jun; Sanberg, Cyndy D; Sutton, Danielle T.; Tan, Jun

    2008-01-01

    Autism is a pervasive developmental disorder characterized by impairments in socialization and communication. There is currently no single molecular marker or laboratory tool capable of diagnosing autism at an early age. The purpose of this study is to explore the plausible use of peripheral biomarkers in the early diagnosis of autism via a sensitive ELISA. Here, we measured plasma secreted amyloid precursor protein alpha (sAPP-?) levels in autistic and aged-matched control blood samples and ...

  8. 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

  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. Sorting by the Cytoplasmic Domain of the Amyloid Precursor Protein Binding Receptor SorLA? †

    OpenAIRE

    Nielsen, Morten S.; Gustafsen, Camilla; Madsen, Peder; Nyengaard, Jens R.; Hermey, Guido; Bakke, Oddmund; Mari, Muriel; Schu, Peter; Pohlmann, Regina; Dennes, André; Petersen, Claus M.

    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 A?-peptide. The receptor is mainly located in vesicles, suggesting a function in protein sorting...

  12. 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...

  13. 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.)

  14. 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

  15. Amyloid ?-Protein C-Terminal Fragments: Formation of Cylindrins and ?-Barrels.

    Science.gov (United States)

    Do, Thanh D; LaPointe, Nichole E; Nelson, Rebecca; Krotee, Pascal; Hayden, Eric Y; Ulrich, Brittany; Quan, Sarah; Feinstein, Stuart C; Teplow, David B; Eisenberg, David; Shea, Joan-Emma; Bowers, Michael T

    2016-01-20

    In order to evaluate potential therapeutic targets for treatment of amyloidoses such as Alzheimer's disease (AD), it is essential to determine the structures of toxic amyloid oligomers. However, for the amyloid ?-protein peptide (A?), thought to be the seminal neuropathogenetic agent in AD, its fast aggregation kinetics and the rapid equilibrium dynamics among oligomers of different size pose significant experimental challenges. Here we use ion-mobility mass spectrometry, in combination with electron microscopy, atomic force microscopy, and computational modeling, to test the hypothesis that A? peptides can form oligomeric structures resembling cylindrins and ?-barrels. These structures are hypothesized to cause neuronal injury and death through perturbation of plasma membrane integrity. We show that hexamers of C-terminal A? fragments, including A?(24-34), A?(25-35) and A?(26-36), have collision cross sections similar to those of cylindrins. We also show that linking two identical fragments head-to-tail using diglycine increases the proportion of cylindrin-sized oligomers. In addition, we find that larger oligomers of these fragments may adopt ?-barrel structures and that ?-barrels can be formed by folding an out-of-register ?-sheet, a common type of structure found in amyloid proteins. PMID:26700445

  16. 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.

  17. 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.

  18. Amyloid Assemblies of Influenza A Virus PB1-F2 Protein Damage Membrane and Induce Cytotoxicity.

    Science.gov (United States)

    Vidic, Jasmina; Richard, Charles-Adrien; Péchoux, Christine; Da Costa, Bruno; Bertho, Nicolas; Mazerat, Sandra; Delmas, Bernard; Chevalier, Christophe

    2016-01-01

    PB1-F2 is a small accessory protein encoded by an alternative open reading frame in PB1 segments of most influenza A virus. PB1-F2 is involved in virulence by inducing mitochondria-mediated immune cells apoptosis, increasing inflammation, and enhancing predisposition to secondary bacterial infections. Using biophysical approaches we characterized membrane disruptive activity of the full-length PB1-F2 (90 amino acids), its N-terminal domain (52 amino acids), expressed by currently circulating H1N1 viruses, and its C-terminal domain (38 amino acids). Both full-length and N-terminal domain of PB1-F2 are soluble at pH values ?6, whereas the C-terminal fragment was found soluble only at pH ? 3. All three peptides are intrinsically disordered. At pH ? 7, the C-terminal part of PB1-F2 spontaneously switches to amyloid oligomers, whereas full-length and the N-terminal domain of PB1-F2 aggregate to amorphous structures. When incubated with anionic liposomes at pH 5, full-length and the C-terminal part of PB1-F2 assemble into amyloid structures and disrupt membrane at nanomolar concentrations. PB1-F2 and its C-terminal exhibit no significant antimicrobial activity. When added in the culture medium of mammalian cells, PB1-F2 amorphous aggregates show no cytotoxicity, whereas PB1-F2 pre-assembled into amyloid oligomers or fragmented nanoscaled fibrils was highly cytotoxic. Furthermore, the formation of PB1-F2 amyloid oligomers in infected cells was directly reflected by membrane disruption and cell death as observed in U937 and A549 cells. Altogether our results demonstrate that membrane-lytic activity of PB1-F2 is closely linked to supramolecular organization of the protein. PMID:26601953

  19. 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.

  20. 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...

  1. Amyloid-β Receptors: The Good, the Bad, and the Prion Protein.

    Science.gov (United States)

    Jarosz-Griffiths, Heledd H; Noble, Elizabeth; Rushworth, Jo V; Hooper, Nigel M

    2016-02-12

    Several different receptor proteins have been identified that bind monomeric, oligomeric, or fibrillar forms of amyloid-β (Aβ). "Good" receptors internalize Aβ or promote its transcytosis out of the brain, whereas "bad" receptors bind oligomeric forms of Aβ that are largely responsible for the synapticloss, memory impairments, and neurotoxicity that underlie Alzheimer disease. The prion protein both removes Aβ from the brain and transduces the toxic actions of Aβ. The clustering of distinct receptors in cell surface signaling platforms likely underlies the actions of distinct oligomeric species of Aβ. These Aβ receptor-signaling platforms provide opportunities for therapeutic intervention in Alzheimer disease. PMID:26719327

  2. The predominant form of the amyloid beta-protein precursor in human brain is protease nexin 2.

    OpenAIRE

    Nostrand, W.E. van; Farrow, J S; Wagner, S. L.; Bhasin, R; Goldgaber, D; Cotman, C. W.; Cunningham, D D

    1991-01-01

    The amyloid beta protein and the amyloid beta-protein precursor (APP) are major constituents of senile plaques and cerebrovascular deposits in patients with Alzheimer disease and Down syndrome. Most human tissues contain mRNA that encodes forms of APP that contain the Kunitz protease inhibitor (KPI+) domain. A major 120-kDa protein corresponding to this KPI+ mRNA is also found in these tissues. This protein is identical to the protease inhibitor protease nexin 2. Brain contains an additional ...

  3. 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

  4. 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.

  5. 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...

  6. Bacterial curli protein promotes the conversion of PAP248-286 into the amyloid SEVI: cross-seeding of dissimilar amyloid sequences.

    Science.gov (United States)

    Hartman, Kevin; Brender, Jeffrey R; Monde, Kazuaki; Ono, Akira; Evans, Margery L; Popovych, Nataliya; Chapman, Matthew R; Ramamoorthy, Ayyalusamy

    2013-01-01

    Fragments of prostatic acid phosphatase (PAP248-286) in human semen dramatically increase HIV infection efficiency by increasing virus adhesion to target cells. PAP248-286 only enhances HIV infection in the form of amyloid aggregates termed SEVI (Semen Enhancer of Viral Infection), however monomeric PAP248-286 aggregates very slowly in isolation. It has therefore been suggested that SEVI fiber formation in vivo may be promoted by exogenous factors. We show here that a bacterially-produced extracellular amyloid (curli or Csg) acts as a catalytic agent for SEVI formation from PAP248-286 at low concentrations in vitro, producing fibers that retain the ability to enhance HIV (Human Immunodeficiency Virus) infection. Kinetic analysis of the cross-seeding effect shows an unusual pattern. Cross-seeding PAP248-286 with curli only moderately affects the nucleation rate while significantly enhancing the growth of fibers from existing nuclei. This pattern is in contrast to most previous observations of cross-seeding, which show cross-seeding partially bypasses the nucleation step but has little effect on fiber elongation. Seeding other amyloidogenic proteins (IAPP (islet amyloid polypeptide) and A?1-40) with curli showed varied results. Curli cross-seeding decreased the lag-time of IAPP amyloid formation but strongly inhibited IAPP elongation. Curli cross-seeding exerted a complicated concentration dependent effect on A?1-40 fibrillogenesis kinetics. Combined, these results suggest that the interaction of amyloidogenic proteins with preformed fibers of a different type can take a variety of forms and is not limited to epitaxial nucleation between proteins of similar sequence. The ability of curli fibers to interact with proteins of dissimilar sequences suggests cross-seeding may be a more general phenomenon than previously supposed. PMID:23638387

  7. Bacterial curli protein promotes the conversion of PAP248-286 into the amyloid SEVI: cross-seeding of dissimilar amyloid sequences

    Directory of Open Access Journals (Sweden)

    Kevin Hartman

    2013-02-01

    Full Text Available Fragments of prostatic acid phosphatase (PAP248-286 in human semen dramatically increase HIV infection efficiency by increasing virus adhesion to target cells. PAP248-286 only enhances HIV infection in the form of amyloid aggregates termed SEVI (Semen Enhancer of Viral Infection, however monomeric PAP248-286 aggregates very slowly in isolation. It has therefore been suggested that SEVI fiber formation in vivo may be promoted by exogenous factors. We show here that a bacterially-produced extracellular amyloid (curli or Csg acts as a catalytic agent for SEVI formation from PAP248-286 at low concentrations in vitro, producing fibers that retain the ability to enhance HIV (Human Immunodeficiency Virus infection. Kinetic analysis of the cross-seeding effect shows an unusual pattern. Cross-seeding PAP248-286 with curli only moderately affects the nucleation rate while significantly enhancing the growth of fibers from existing nuclei. This pattern is in contrast to most previous observations of cross-seeding, which show cross-seeding partially bypasses the nucleation step but has little effect on fiber elongation. Seeding other amyloidogenic proteins (IAPP (islet amyloid polypeptide and A?1?40 with curli showed varied results. Curli cross-seeding decreased the lag-time of IAPP amyloid formation but strongly inhibited IAPP elongation. Curli cross-seeding exerted a complicated concentration dependent effect on A?1?40 fibrillogenesis kinetics. Combined, these results suggest that the interaction of amyloidogenic proteins with preformed fibers of a different type can take a variety of forms and is not limited to epitaxial nucleation between proteins of similar sequence. The ability of curli fibers to interact with proteins of dissimilar sequences suggests cross-seeding may be a more general phenomenon than previously supposed.

  8. 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

  9. 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...

  10. Effect of electroconvulsive therapy on serum myelin basic protein immunoreactivity.

    OpenAIRE

    Hoyle, N. R.; Pratt, R T; Thomas, D G

    1984-01-01

    A sensitive radioimmunoassay that can detect brain damage in cases of head injury and stroke was applied to blood samples from 13 patients before and after they received multiple treatments with electroconvulsive therapy for psychiatric disorder. None of the patients showed a significant increase in serum myelin basic protein immunoreactivity. As increased serum myelin basic protein immunoreactivity may reflect myelin damage it is apparent that in these patients electroconvulsive therapy did ...

  11. Reduction of ?-Amyloid Levels by Novel Protein Kinase C? Activators

    OpenAIRE

    Nelson, Thomas J.; Cui, Changhai; Luo, Yuan; Alkon, Daniel L.

    2009-01-01

    Isoform-specific protein kinase C (PKC) activators may be useful as therapeutic agents for the treatment of Alzheimer disease. Three new ?-specific PKC activators, made by cyclopropanation of polyunsaturated fatty acids, have been developed. These activators, AA-CP4, EPA-CP5, and DHA-CP6, activate PKC? in a dose-dependent manner. Unlike PKC activators that bind to the 1,2-diacylglycerol-binding site, such as bryostatin and phorbol esters, which produce prolonged down-regulation, the new activ...

  12. 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

  13. 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

  14. Studies of the aggregation of mutant proteins in vitro provide insights into the genetics of amyloid diseases.

    Science.gov (United States)

    Chiti, Fabrizio; Calamai, Martino; Taddei, Niccolo; Stefani, Massimo; Ramponi, Giampietro; Dobson, Christopher M

    2002-12-10

    Protein aggregation and the formation of highly insoluble amyloid structures is associated with a range of debilitating human conditions, which include Alzheimer's disease, Parkinson's disease, and the Creutzfeldt-Jakob disease. Muscle acylphosphatase (AcP) has already provided significant insights into mutational changes that modulate amyloid formation. In the present paper, we have used this system to investigate the effects of mutations that modify the charge state of a protein without affecting significantly the hydrophobicity or secondary structural propensities of the polypeptide chain. A highly significant inverse correlation was found to exist between the rates of aggregation of the protein variants under denaturing conditions and their overall net charge. This result indicates that aggregation is generally favored by mutations that bring the net charge of the protein closer to neutrality. In light of this finding, we have analyzed natural mutations associated with familial forms of amyloid diseases that involve alteration of the net charge of the proteins or protein fragments associated with the diseases. Sixteen mutations have been identified for which the mechanism of action that causes the pathological condition is not yet known or fully understood. Remarkably, 14 of these 16 mutations cause the net charge of the corresponding peptide or protein that converts into amyloid deposits to be reduced. This result suggests that charge has been a key parameter in molecular evolution to ensure the avoidance of protein aggregation and identifies reduction of the net charge as an important determinant in at least some forms of protein deposition diseases. PMID:12374855

  15. 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

  16. 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...

  17. 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...

  18. Serum amyloid P: a systemic regulator of the innate immune response.

    Science.gov (United States)

    Cox, Nehemiah; Pilling, Darrell; Gomer, Richard H

    2014-11-01

    The pentraxin SAP reduces neutrophil adhesion to ECM proteins, inhibits the differentiation of monocytes into fibrocytes, attenuates profibrotic macrophages, activates the complement pathway, and promotes phagocytosis of cell debris. Together, these effects of SAP regulate key aspects of inflammation and set a threshold for immune cell activation. Here, we present a review of SAP biology with an emphasis on SAP receptor interactions and how the effect of SAP on monocytes and macrophages has been explored to develop this protein as a therapeutic for renal and lung injuries. We also discuss how there remain many unanswered questions about the role of SAP in innate immunity. PMID:24804675

  19. 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

  20. 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

  1. 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

  2. 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

  3. Gold binding to blood cells and serum proteins during chrysotherapy.

    OpenAIRE

    Stadt, R.J. van de; Abbo-Tilstra, B

    1980-01-01

    The binding of gold to peripheral erythrocytes and serum protein fractions was studied during chrysotherapy of 1 to 2 years' duration in 43 patients with rheumatoid arthritis. In 45% of the patients more than 10% of the gold was found to be strongly bound to blood cells. 5--15% of the metal is bound to non-albumin protein fractions at serum gold concentrations larger than 2 microgram/ml. In contrast to the cellular binding of gold the relative binding of gold to non-albumin proteins was inver...

  4. 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...

  5. 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 ...

  6. 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)

  7. 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

  8. Structure of Alzheimer’s disease amyloid precursor protein copper-binding domain at atomic resolution

    International Nuclear Information System (INIS)

    An atomic resolution structure of the copper-binding domain of the Alzheimer’s disease amyloid precursor protein is presented. Amyloid precursor protein (APP) plays a central role in the pathogenesis of Alzheimer’s disease, as its cleavage generates the A? peptide that is toxic to cells. APP is able to bind Cu2+ and reduce it to Cu+ through its copper-binding domain (CuBD). The interaction between Cu2+ and APP leads to a decrease in A? production and to alleviation of the symptoms of the disease in mouse models. Structural studies of CuBD have been undertaken in order to better understand the mechanism behind the process. Here, the crystal structure of CuBD in the metal-free form determined to ultrahigh resolution (0.85 Å) is reported. The structure shows that the copper-binding residues of CuBD are rather rigid but that Met170, which is thought to be the electron source for Cu2+ reduction, adopts two different side-chain conformations. These observations shed light on the copper-binding and redox mechanisms of CuBD. The structure of CuBD at atomic resolution provides an accurate framework for structure-based design of molecules that will deplete A? production

  9. Structure of Alzheimer’s disease amyloid precursor protein copper-binding domain at atomic resolution

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Geoffrey Kwai-Wai; Adams, Julian J. [Biota Structural Biology Laboratory, St Vincent’s Institute, 9 Princes Street, Fitzroy, Victoria 3065 (Australia); Cappai, Roberto [Department of Pathology and Centre for Neuroscience, The University of Melbourne, Victoria 3010 (Australia); The Mental Health Research Institute of Victoria, Parkville, Victoria 3052 (Australia); Bio21 Institute, The University of Melbourne, Victoria 3010 (Australia); Parker, Michael W., E-mail: mparker@svi.edu.au [Biota Structural Biology Laboratory, St Vincent’s Institute, 9 Princes Street, Fitzroy, Victoria 3065 (Australia); Bio21 Institute, The University of Melbourne, Victoria 3010 (Australia)

    2007-10-01

    An atomic resolution structure of the copper-binding domain of the Alzheimer’s disease amyloid precursor protein is presented. Amyloid precursor protein (APP) plays a central role in the pathogenesis of Alzheimer’s disease, as its cleavage generates the A? peptide that is toxic to cells. APP is able to bind Cu{sup 2+} and reduce it to Cu{sup +} through its copper-binding domain (CuBD). The interaction between Cu{sup 2+} and APP leads to a decrease in A? production and to alleviation of the symptoms of the disease in mouse models. Structural studies of CuBD have been undertaken in order to better understand the mechanism behind the process. Here, the crystal structure of CuBD in the metal-free form determined to ultrahigh resolution (0.85 Å) is reported. The structure shows that the copper-binding residues of CuBD are rather rigid but that Met170, which is thought to be the electron source for Cu{sup 2+} reduction, adopts two different side-chain conformations. These observations shed light on the copper-binding and redox mechanisms of CuBD. The structure of CuBD at atomic resolution provides an accurate framework for structure-based design of molecules that will deplete A? production.

  10. Beta-secretase cleavage of Alzheimer's amyloid precursor protein by the transmembrane aspartic protease BACE.

    Science.gov (United States)

    Vassar, R; Bennett, B D; Babu-Khan, S; Kahn, S; Mendiaz, E A; Denis, P; Teplow, D B; Ross, S; Amarante, P; Loeloff, R; Luo, Y; Fisher, S; Fuller, J; Edenson, S; Lile, J; Jarosinski, M A; Biere, A L; Curran, E; Burgess, T; Louis, J C; Collins, F; Treanor, J; Rogers, G; Citron, M

    1999-10-22

    Cerebral deposition of amyloid beta peptide (Abeta) is an early and critical feature of Alzheimer's disease. Abeta generation depends on proteolytic cleavage of the amyloid precursor protein (APP) by two unknown proteases: beta-secretase and gamma-secretase. These proteases are prime therapeutic targets. A transmembrane aspartic protease with all the known characteristics of beta-secretase was cloned and characterized. Overexpression of this protease, termed BACE (for beta-site APP-cleaving enzyme) increased the amount of beta-secretase cleavage products, and these were cleaved exactly and only at known beta-secretase positions. Antisense inhibition of endogenous BACE messenger RNA decreased the amount of beta-secretase cleavage products, and purified BACE protein cleaved APP-derived substrates with the same sequence specificity as beta-secretase. Finally, the expression pattern and subcellular localization of BACE were consistent with that expected for beta-secretase. Future development of BACE inhibitors may prove beneficial for the treatment of Alzheimer's disease. PMID:10531052

  11. 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

  12. Protein disulfide isomerase ameliorates ?-cell dysfunction in pancreatic islets overexpressing human islet amyloid polypeptide.

    Science.gov (United States)

    Montane, Joel; de Pablo, Sara; Obach, Mercè; Cadavez, Lisa; Castaño, Carlos; Alcarraz-Vizán, Gema; Visa, Montserrat; Rodríguez-Comas, Júlia; Parrizas, Marcelina; Servitja, Joan Marc; Novials, Anna

    2016-01-15

    Human islet amyloid polypeptide (hIAPP) is the major component of amyloid deposits in islets of type 2 diabetic patients. hIAPP misfolding and aggregation is one of the factors that may lead to ?-cell dysfunction and death. Endogenous chaperones are described to be important for the folding and functioning of proteins. Here, we examine the effect of the endoplasmic reticulum chaperone protein disulfide isomerase (PDI) on ?-cell dysfunction. Among other chaperones, PDI was found to interact with hIAPP in human islet lysates. Furthermore, intrinsically recovered PDI levels were able to restore the effect of high glucose- and palmitate-induced ?-cell dysfunction by increasing 3.9-fold the glucose-stimulated insulin secretion levels and restoring insulin content up to basal control values. Additionally, PDI transduction decreased induced apoptosis by glucolipotoxic conditions. This approach could reveal a new therapeutic target and aid in the development of strategies to improve ?-cell dysfunction in type 2 diabetic patients. PMID:26607804

  13. 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.

  14. LINGO-1 promotes lysosomal degradation of amyloid-β protein precursor

    Directory of Open Access Journals (Sweden)

    Rian de Laat

    2015-03-01

    Full Text Available Sequential proteolytic cleavages of amyloid-β protein precursor (AβPP by β-secretase and γ-secretase generate amyloid β (Aβ peptides, which are thought to contribute to Alzheimer's disease (AD. Much of this processing occurs in endosomes following endocytosis of AβPP from the plasma membrane. However, this pathogenic mode of processing AβPP may occur in competition with lysosomal degradation of AβPP, a common fate of membrane proteins trafficking through the endosomal system. Following up on published reports that LINGO-1 binds and promotes the amyloidogenic processing of AβPP we have examined the consequences of LINGO-1/AβPP interactions. We report that LINGO-1 and its paralogs, LINGO-2 and LINGO-3, decrease processing of AβPP in the amyloidogenic pathway by promoting lysosomal degradation of AβPP. We also report that LINGO-1 levels are reduced in AD brain, representing a possible pathogenic mechanism stimulating the generation of Aβ peptides in AD.

  15. 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.

  16. 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

  17. 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.

  18. 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...

  19. 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...

  20. 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...

  1. Screening serum hepatocellular carcinoma-associated proteins by SELDI-based protein spectrum analysis

    Directory of Open Access Journals (Sweden)

    Jie-Feng Cui, Yin-Kun Liu, Hai-Jun Zhou, Xiao-Nan Kang, Cheng Huang, Yi-Feng He, Zhao-You Tang, Toshimasa Uemura

    2008-02-01

    Full Text Available AIM: To find out potential serum hepatocellular carcinoma (HCC-associated proteins with low molecular weight and low abundance by SELDI-based serum protein spectra analysis, that will have much application in the diagnosis or differentiated diagnosis of HCC, as well as giving a better understanding of the mechanism of hepato-carcinogenesis.METHODS: Total serum samples were collected with informed consent from 81 HCC patients with HBV(+/cirrhosis(+, 36 cirrhosis patients and 43 chronic hepatitis B patients. Serum protein fingerprint profiles were first generated by selected WCX2 protein chip capture integrating with SELDI-TOF-MS, then normalized and aligned by Ciphergen SELDI Software 3.1.1 with Biomarker Wizard. Comparative analysis of the intensity of corresponding protein fingerprint peaks in normalized protein spectra, some protein peaks with significant difference between HCC and cirrhosis or chronic hepatitis B were found.RESULTS: One hundred and twenty-eight serum protein peaks between 2000 and 30 000Da were identified under the condition of signal-to-noise > 5 and minimum threshold for cluster > 20%. Eighty-seven of these proteins were showed significant differences in intensity between HCC and cirrhosis (P < 0.05. Of the above differential proteins, 45 proteins had changes greater than two-fold, including 15 upregulated proteins and 30 downregulated proteins in HCC serum. Between HCC and chronic hepatitis B, 9 of 52 differential proteins (P < 0.05 had intensities of more than two-fold, including 2 upregulated proteins and 7 downregulated proteins in HCC serum. Between cirrhosis and chronic hepatitis B, 28 of 79 significant differential proteins (P < 0.05 changes greater than two-fold in intensity, including 17 upregulated proteins and 11 downregulated proteins in cirrhosis serum. For the analysis of these leading differential proteins in subtraction difference mode among three diseases, the five common downregulated proteins in HCC serum (M/Z 2870, 3941, 2688, 3165, 5483 and two common upregulated proteins (M/Z 3588, 2017 in HCC and cirrhosis serum were screened.CONCLUSION: Because the interference of unspecific secreted proteins from hepatitis B and cirrhosis could be eliminated partly in HCC serum under subtraction difference analysis, these seven common differential proteins have the obvious advantage of specificity for evaluating the pathological state of HCC and might become novel candidate biomarkers in the diagnosis of HCC.

  2. Identification in milk of a serum amyloid A peptide chemoattractant for B lymphoblasts

    Science.gov (United States)

    de Jesus Rodriguez, Berardo; Chevaleyre, Claire; Henry, Gwénaële; Mollé, Daniel; Virlogeux-Payant, Isabelle; Berri, Mustapha; Boulay, François; Léonil, Joëlle; Meurens, François; Salmon, Henri

    2009-01-01

    Background Normal mammary gland contains an extravascular population of B lymphoblasts, precursors of the immunoglobulin plasma cells that play a key role in the passive protection of neonates by secreting immunoglobulins to colostrum and milk. We investigated the presence of chemoattractants in the milk by analysing the chemoattractant activity of various fractions of this secretion. Milk chemoattractants are potentially involved in the recruitment of lymphocytes from the maternal bloodstream in lactating mammary glands. Results The dilution-related lymphoid cell chemoattraction of whey was associated with a < 10 kDa ultrafiltrate. Active fractions were purified by reverse-phase high performance liquid chromatography. Two peptides of 2.7 kDa (DMREANYKNSDKYFHARGNYDAA) and 1 kDa (RPPGLPDKY) were identified as fragments of the SAA protein family, tentatively identified as SAA2. Only the 2.7 kDa synthetic peptide displayed chemotactic activity, at two different optimal concentrations. At the lower concentration (3.7 nM), it attracted B-cell lymphoblasts, whereas at the higher (3.7 ?M), it attracted B lymphocytes. Then, the SAA mRNA expression was analysed and we observed more SAA transcripts during lactation than gestation. Conclusion These data are consistent with the SAA23–45 fragment being involved in preplasma B-cell recruitment to the mammary gland and resultant benefit to the neonate. PMID:19166592

  3. 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

  4. 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.

  5. Single-molecule imaging of individual amyloid protein aggregates in human biofluids

    DEFF Research Database (Denmark)

    Horrocks, Mathew Harry; Lee, Steven F; Gandhi, Sonia; Magdalinou, Nadia K; Chen, Serene W; Devine, Michael J; Tosatto, Laura; Kjaergaard, Magnus; Beckwith, Joseph S; Zetterberg, Henrik; Iljina, Marija; Cremades, Nunilo; Dobson, Christopher M; Wood, Nicholas W; Klenerman, David

    2016-01-01

    amyloid fibrils and oligomers using single-molecule fluorescence microscopy. We demonstrate that this method is able to detect the presence of amyloid aggregates of alpha-synuclein, tau and amyloid-?. In addition, we show that aggregates can also be identified in human cerebrospinal fluid (CSF...

  6. Axonal transport, amyloid precursor protein, kinesin-1, and the processing apparatus: revisited.

    Science.gov (United States)

    Lazarov, Orly; Morfini, Gerardo A; Lee, Edward B; Farah, Mohamed H; Szodorai, Anita; DeBoer, Scott R; Koliatsos, Vassilis E; Kins, Stefan; Lee, Virginia M-Y; Wong, Philip C; Price, Donald L; Brady, Scott T; Sisodia, Sangram S

    2005-03-01

    The sequential enzymatic actions of beta-APP cleaving enzyme 1 (BACE1), presenilins (PS), and other proteins of the gamma-secretase complex liberate beta-amyloid (Abeta) peptides from larger integral membrane proteins, termed beta-amyloid precursor proteins (APPs). Relatively little is known about the normal function(s) of APP or the neuronal compartment(s) in which APP undergoes proteolytic processing. Recent studies have been interpreted as consistent with the idea that APP serves as a kinesin-1 cargo receptor and that PS and BACE1 are associated with the APP-resident membranous cargos that undergo rapid axonal transport. In this report, derived from a collaboration among several independent laboratories, we examined the potential associations of APP and kinesin-1 using glutathione S-transferase pull-down and coimmunoprecipitation assays. In addition, we assessed the trafficking of membrane proteins in the sciatic nerves of transgenic mice with heterozygous or homozygous deletions of APP. In contrast to previous reports, we were unable to find evidence for direct interactions between APP and kinesin-1. Furthermore, the transport of kinesin-1 and tyrosine kinase receptors, previously reported to require APP, was unchanged in axons of APP-deficient mice. Finally, we show that two components of the APP proteolytic machinery, i.e., PS1 and BACE1, are not cotransported with APP in the sciatic nerves of mice. These findings suggest that the hypothesis that APP serves as a kinesin-1 receptor and that the proteolytic processing machinery responsible for generating Abeta is transported in the same vesicular compartment in axons of peripheral nerves requires revision. PMID:15745965

  7. Serum proteins in atomic industry workers

    International Nuclear Information System (INIS)

    At present time the clinical and experimental materials have been accumulated, which evidence about the influence of irradiation on different sides of the protein metabolism. The most of these studies have been conducted at the early time period after acute and chronic irradiation exposures. Because data on more late consequences of irradiation influence on the protein metabolism in humans are not numerous and have some differences, it is necessary to have future studies of this problem. The results, obtained for the last years in epidemiological studies of humans, indicate on the relationship the protein metabolism changes with aging, increased morbidity and mortality and confirm the importance to continue the studies in this area. (author)

  8. Characterization of cDNA encoding a human sperm membrane protein related to A4 amyloid protein

    International Nuclear Information System (INIS)

    A rat testis λgt11 cDNA library was screened with a monoclonal antibody raised against a human sperm membrane protein designated YWK-II. A clone was found with a cDNA insert composed of 1837 base pairs that contained an open reading frame coding for 191 amino acid residues. The deduced polypeptide contained a segment with high homology to the transmembrane-cytoplasmic domains of the A4 amyloid protein found in brain plaques of Alzheimer disease patients. A sequence of basic amino acid residues, Arg-Lys-Arg, was found instead of Lys-Lys-Lys at the probable membrane-cytoplasmic junction that may be a unique property of sperm membrane proteins

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

    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...... 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......PCR, 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....

  15. Doped diamond-like carbon coatings for surgical instruments reduce protein and prion-amyloid biofouling and improve subsequent cleaning.

    Science.gov (United States)

    Secker, T J; Hervé, R; Zhao, Q; Borisenko, K B; Abel, E W; Keevil, C W

    2012-01-01

    Doped diamond-like carbon (DLC) coatings offer potential antifouling surfaces against microbial and protein attachment. In particular, stainless steel surgical instruments are subject to tissue protein and resilient prion protein attachment, making decontamination methods used in sterile service departments ineffective, potentially increasing the risk of iatrogenic Creutzfeldt-Jakob disease during surgical procedures. This study examined the adsorption of proteins and prion-associated amyloid to doped DLC surfaces and the efficacy of commercial cleaning chemistries applied to these spiked surfaces, compared to titanium nitride coating and stainless steel. Surfaces inoculated with ME7-infected brain homogenate were visualised using SYPRO Ruby/Thioflavin T staining and modified epi-fluorescence microscopy before and after cleaning. Reduced protein and prion amyloid contamination was observed on the modified surfaces and subsequent decontamination efficacy improved. This highlights the potential for a new generation of coatings for surgical instruments to reduce the risk of iatrogenic CJD infection. PMID:22694725

  16. 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.

  17. Stabilization of native amyloid ?-protein oligomers by Copper and Hydrogen peroxide Induced Cross-linking of Unmodified Proteins (CHICUP).

    Science.gov (United States)

    Williams, Thomas L; Serpell, Louise C; Urbanc, Brigita

    2016-03-01

    Oligomeric assemblies are postulated to be proximate neurotoxic species in human diseases associated with aberrant protein aggregation. Their heterogeneous and transient nature makes their structural characterization difficult. Size distributions of oligomers of several amyloidogenic proteins, including amyloid ?-protein (A?) relevant to Alzheimer's disease (AD), have been previously characterized in vitro by photo-induced cross-linking of unmodified proteins (PICUP) followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Due to non-physiological conditions associated with the PICUP chemistry, A? oligomers cross-linked by PICUP may not be representative of in vivo conditions. Here, we examine an alternative Copper and Hydrogen peroxide Induced Cross-linking of Unmodified Proteins (CHICUP), which utilizes naturally occurring divalent copper ions and hydrogen peroxide and does not require photo activation. Our results demonstrate that CHICUP and PICUP applied to the two predominant A? alloforms, A?40 and A?42, result in similar oligomer size distributions. Thioflavin T fluorescence data and atomic force microscopy images demonstrate that both CHICUP and PICUP stabilize A? oligomers and attenuate fibril formation. Relative to noncross-linked peptides, CHICUP-treated A?40 and A?42 cause prolonged disruption to biomimetic lipid vesicles. CHICUP-stabilized A? oligomers link the amyloid cascade, metal, and oxidative stress hypotheses of AD into a more comprehensive understanding of the molecular basis of AD pathology. Because copper and hydrogen peroxide are elevated in the AD brain, CHICUP-stabilized A? oligomers are biologically relevant and should be further explored as a new therapeutic target. PMID:26699836

  18. Calcium ionophore A23187 specifically decreases the secretion of beta-secretase cleaved amyloid precursor protein during apoptosis in primary rat cortical cultures

    DEFF Research Database (Denmark)

    Sennvik, K; Benedikz, Eirikur; Fastbom, J; Sundström, E; Winblad, B; Ankarcrona, M

    2001-01-01

    Alzheimer's disease (AD) is characterized by the degeneration and loss of neurons, intracellular neurofibrillary tangles and the accumulation of extracellular senile plaques consisting mainly of beta-amyloid (A beta). A beta is generated from the amyloid precursor protein (APP) by sequential beta...... homeostasis is an important apoptotic effector specifically affecting the beta-secretase cleavage of APP....

  19. 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

  20. Competitive protein adsorption to polymer surface from human serum

    DEFF Research Database (Denmark)

    Holmberg, Maria; Jensen, Karin Bagger Stibius; Larsen, Niels Bent; Hou, Xiaolin

    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 ...

  1. 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.

  2. 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...

  3. Identification of a Serum amyloid A gene and the association of SNPs with Vibrio-resistance and growth traits in the clam Meretrix meretrix.

    Science.gov (United States)

    Zou, Linhu; Liu, Baozhong

    2015-04-01

    Serum amyloid A (SAA), an acute response protein as well as an apolipoprotein, is considered to play crucial roles in both innate immunity and lipid metabolism. In this study, a SAA gene (MmSAA) was identified in the clam Meretrix meretrix. The full length DNA of MmSAA was 1407bp, consisting of three exons and two introns. The distribution of MmSAA in clam tissues was examined with the highest expression in hepatopancreas. In response to the Vibrio parahaemolyticus challenge, MmSAA mRNA showed significantly higher expression at 24 h post-challenge in experimental clams (P polymorphisms (SNPs) in the DNA partial sequence of MmSAA were discovered and examined for their association with Vibrio-resistance and growth traits, respectively. The single SNP association analysis indicated that five single SNPs (g.42, g.72, g.82, g.147 and g.165) were significantly associated with Vibrio-resistance (P < 0.05). Haplotype analysis produced additional support for association with the Chi-square values 6.393 (P = 0.012). Among the five selected SNPs, the effect of a missense mutation (g.82, A ? G) was detected by site-directed mutagenesis with fusion expression of protein assay, and the result showed that the recombinant plasmids containing wild-type pET30a-MmSAA had more inhibition effect than the mutant ones on the growth rate of the host bacteria. In addition, four growth traits of the clams in 09G3SPSB population were recorded and the SNP g.176 was found to be significantly associated with the growth traits with the Global score value 0.790 (P = 0.015). Our findings suggested that common genetic variation in MmSAA might contribute to the risk of susceptibility to Vibrio infection and might be associated with the growth traits in the clams M. meretrix, and more works are still needed to validate these SNPs as potential markers for actual selective breeding. PMID:25602707

  4. 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

  5. Electrophoretic properties of beta-lactam and serum protein conjugates.

    Science.gov (United States)

    Zdziarski, P

    2000-01-01

    Beta-lactam antibiotics can easy bind to protein. Available information on the nature of the conjugates is rather poor. In this study, agarose electrophoresis was used to determine and comparison physicochemical properties of the complexes. Benzylpenicillin, ampicillin, cefoperazone, cefotaxime, ceftazidime, cefuroxime, ceftriaxone, imipenem and serum protein were used for free generation drug-protein conjugates. Agarose electrophoresis shows heterogeneous migration of the conjugates. Interestingly-binding of benzylpenicillin and ampicillin exerts an effect on electrophoretic migration of albumin and globulin, but others--only serum albumin. Binding of ampicillin shows down migration of all anionic fractions of plasma protein, benzylpenicillin--anionic and cationic. Otherwise--migration of albumin was accelerate by others. This finding can explain higher frequency of penicillins hypersensitivity than cephalosporins, carbapenems or monobaktams. The commercially available and cheap procedure allows to execute the screening of physicochemical properties, which exert an effect on electrophoretic mobility of protein i.e. electric charge and molecule length (Stockes's diameter). Therefore, the electrophoretic mobility modification probably reflects the transformation of molecular weight, charge and space structure serum proteins by binding of beta-lactam antibiotics. PMID:11243245

  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

    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, β-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. Sex hormone-related neurosteroids differentially rescue bioenergetic deficits induced by amyloid-? or hyperphosphorylated tau protein.

    Science.gov (United States)

    Grimm, Amandine; Biliouris, Emily E; Lang, Undine E; Götz, Jürgen; Mensah-Nyagan, Ayikoe Guy; Eckert, Anne

    2016-01-01

    Alzheimer's disease (AD) is an age-related neurodegenerative disease marked by a progressive cognitive decline. Metabolic impairments are common hallmarks of AD, and amyloid-? (A?) peptide and hyperphosphorylated tau protein-the two foremost histopathological signs of AD-have been implicated in mitochondrial dysfunction. Neurosteroids have recently shown promise in alleviating cognitive and neuronal sequelae of AD. The present study evaluates the impact of neurosteroids belonging to the sex hormone family (progesterone, estradiol, estrone, testosterone, 3?-androstanediol) on mitochondrial dysfunction in cellular models of AD: human neuroblastoma cells (SH-SY5Y) stably transfected with constructs encoding (1) the human amyloid precursor protein (APP) resulting in overexpression of APP and A?, (2) wild-type tau (wtTau), and (3) mutant tau (P301L), that induces abnormal tau hyperphosphorylation. We show that while APP and P301L cells both display a drop in ATP levels, they present distinct mitochondrial impairments with regard to their bioenergetic profiles. The P301L cells presented a decreased maximal respiration and spare respiratory capacity, while APP cells exhibited, in addition, a decrease in basal respiration, ATP turnover, and glycolytic reserve. All neurosteroids showed beneficial effects on ATP production and mitochondrial membrane potential in APP/A? overexpressing cells while only progesterone and estradiol increased ATP levels in mutant tau cells. Of note, testosterone was more efficient in alleviating A?-induced mitochondrial deficits, while progesterone and estrogen were the most effective neurosteroids in our model of AD-related tauopathy. Our findings lend further support to the neuroprotective effects of neurosteroids in AD and may open new avenues for the development of gender-specific therapeutic approaches in AD. PMID:26198711

  10. 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, β-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.

  11. 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

  12. {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.)

  13. Binding of an oxindole alkaloid from Uncaria tomentosa to amyloid protein (Abeta1-40).

    Science.gov (United States)

    Frackowiak, Teresa; Baczek, Tomasz; Roman, Kaliszana; Zbikowska, Beata; Gle?sk, Micha?; Fecka, Izabela; Cisowski, Wojciech

    2006-01-01

    The primary aim of this work was to determine the interactions of an oxindole alkaloid (mitraphylline) isolated from Uncaria tomentosa with beta-amyloid 1-40 (Abeta1-40 protein) applying the capillary electrophoresis (CE) method. Specifically the Hummel-Dreyer method and Scatchard analysis were performed to study the binding of oxindole alkaloids with Abeta1-40 protein. Prior to these studies extraction of the alkaloid of interest was carried out. Identification of the isolated alkaloid was performed by the use of thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) combined with electrospray ionization mass spectrometry (ESI-MS). The proposed approach was proved to be an efficient and accurate method for specific compound isolation and identification purposes. Moreover, analytical information from the CE approach can be considered as the valuable tool for binding constant determination. The binding constant of mitraphylline with Abeta1-40 protein determined by the Hummel-Dreyer method and Scatchard analysis equals K = 9.95 x 10(5) M(-1). The results obtained showed the significant binding of the tested compound with Abeta1-40 protein. These results are discussed and interpreted in the view of developing a strategy for identification of novel compounds of great importance in Alzheimer disease therapy. PMID:17294693

  14. 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...

  15. 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.

  16. 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...

  17. Mitochondrial dysfunction in a transgenic mouse model expressing human amyloid precursor protein (APP) with the Arctic mutation.

    Science.gov (United States)

    Rönnbäck, Annica; Pavlov, Pavel F; Mansory, Mansorah; Gonze, Prisca; Marlière, Nicolas; Winblad, Bengt; Graff, Caroline; Behbahani, Homira

    2016-02-01

    Accumulation of amyloid ?-peptide (A?) in the brain is an important event in the pathogenesis of Alzheimer disease. We have used a transgenic mouse model expressing human amyloid precursor protein (APP) with the Arctic mutation to investigate whether A? deposition is correlated with mitochondrial functions in these animals. We found evidence of mitochondrial dysfunction (i.e., decreased mitochondrial membrane potential, increased production of reactive oxygen species and oxidative DNA damage) at 6 months of age, when the mice showed very mild A? deposition. More pronounced mitochondrial abnormalities were present in 24-month-old TgAPParc mice with more extensive A? pathology. This study demonstrates for the first time mitochondrial dysfunction in transgenic mice with a mutation within the A? peptide (the Arctic APP mutation), and confirms previous studies suggesting that mitochondrial dysfunction and oxidative stress is an early event in the pathogenesis of Alzheimer disease. This study demonstrates mitochondrial dysfunction in transgenic mice with a mutation within the amyloid beta (A?) peptide (the Arctic amyloid precursor protein (APP) mutation). We found evidence of mitochondrial dysfunction (i.e. decreased mitochondrial membrane potential (MMP), increased production of reactive oxygen species (ROS) and oxidative DNA damage) at 6 months of age, when very mild A? deposition is present in the mice. Also, the cytochrome c (COX) activity was significantly decreased in mitochondria from transgenic mice at 24 months of age. PMID:26500157

  18. 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

  19. 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...

  20. 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

  1. 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

  2. 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

  3. Inflammatory Eicosanoids Increase Amyloid Precursor Protein Expression via Activation of Multiple Neuronal Receptors.

    Science.gov (United States)

    Herbst-Robinson, Katie J; Liu, Li; James, Michael; Yao, Yuemang; Xie, Sharon X; Brunden, Kurt R

    2015-01-01

    Senile plaques comprised of A? peptides are a hallmark of Alzheimer's disease (AD) brain, as are activated glia that release inflammatory molecules, including eicosanoids. Previous studies have demonstrated that amyloid precursor protein (APP) and A? levels can be increased through activation of thromboxane A2-prostanoid (TP) receptors on neurons. We demonstrate that TP receptor regulation of APP expression depends on G?q-signaling and conventional protein kinase C isoforms. Importantly, we discovered that G?q-linked prostaglandin E2 and leukotriene D4 receptors also regulate APP expression. Prostaglandin E2 and thromboxane A2, as well as total APP levels, were found to be elevated in the brains of aged 5XFAD transgenic mice harboring A? plaques and activated glia, suggesting that increased APP expression resulted from eicosanoid binding to G?q-linked neuronal receptors. Notably, inhibition of eicosanoid synthesis significantly lowered brain APP protein levels in aged 5XFAD mice. These results provide new insights into potential AD therapeutic strategies. PMID:26672557

  4. 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.

  5. 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.

  6. 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...

  7. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, D.; Gardiner, K.; Kao, F.T.; Tanzi, R.; Watkins, P.; Gusella, J.F. (Eleanor Roosevelt Institute for Cancer Research, Denver, CO (USA))

    1988-11-01

    The gene encoding the {beta}-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 {beta}-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 {beta}-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 {beta}-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.

  9. Comparative transcriptome profiling of amyloid precursor protein family members in the adult cortex

    Directory of Open Access Journals (Sweden)

    Eils Roland

    2011-03-01

    Full Text Available Abstract Background The ?-amyloid precursor protein (APP and the related ?-amyloid precursor-like proteins (APLPs undergo complex proteolytic processing giving rise to several fragments. Whereas it is well established that A? accumulation is a central trigger for Alzheimer's disease, the physiological role of APP family members and their diverse proteolytic products is still largely unknown. The secreted APPs? ectodomain has been shown to be involved in neuroprotection and synaptic plasticity. The ?-secretase-generated APP intracellular domain (AICD functions as a transcriptional regulator in heterologous reporter assays although its role for endogenous gene regulation has remained controversial. Results To gain further insight into the molecular changes associated with knockout phenotypes and to elucidate the physiological functions of APP family members including their proposed role as transcriptional regulators, we performed DNA microarray transcriptome profiling of prefrontal cortex of adult wild-type (WT, APP knockout (APP-/-, APLP2 knockout (APLP2-/- and APPs? knockin mice (APP?/? expressing solely the secreted APPs? ectodomain. Biological pathways affected by the lack of APP family members included neurogenesis, transcription, and kinase activity. Comparative analysis of transcriptome changes between mutant and wild-type mice, followed by qPCR validation, identified co-regulated gene sets. Interestingly, these included heat shock proteins and plasticity-related genes that were both down-regulated in knockout cortices. In contrast, we failed to detect significant differences in expression of previously proposed AICD target genes including Bace1, Kai1, Gsk3b, p53, Tip60, and Vglut2. Only Egfr was slightly up-regulated in APLP2-/- mice. Comparison of APP-/- and APP?/? with wild-type mice revealed a high proportion of co-regulated genes indicating an important role of the C-terminus for cellular signaling. Finally, comparison of APLP2-/- on different genetic backgrounds revealed that background-related transcriptome changes may dominate over changes due to the knockout of a single gene. Conclusion Shared transcriptome profiles corroborated closely related physiological functions of APP family members in the adult central nervous system. As expression of proposed AICD target genes was not altered in adult cortex, this may indicate that these genes are not affected by lack of APP under resting conditions or only in a small subset of cells.

  10. 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...

  11. 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...

  12. Bacterial contamination and the transport vial material affect cerebrospinal fluid concentrations of ?-Amyloid and Tau protein as determined by enzyme immunoassay.

    OpenAIRE

    Fronek, Kathrin; Lange, Peter; Spreer, Annette; Eiffert, Helmut; Nau, Roland

    2011-01-01

    BACKGROUND/AIMS: Determination of marker proteins of neuronal degeneration in cerebrospinal fluid (CSF) is of increasing importance. However, preanalytical problems may compromise the results. METHODS: We studied the influence of the transport tube material and shaking at room temperature on the CSF concentrations of ?-amyloid and tau protein determined by enzyme immunoassays. RESULTS: The materials of the transport tube moderately influenced the CSF concentrations of ?-amyloid and ...

  13. 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

  14. Transmembrane Amyloid-Related Proteins in CSF as Potential Biomarkers for Alzheimer’s Disease

    Science.gov (United States)

    Lopez-Font, Inmaculada; Cuchillo-Ibañez, Inmaculada; Sogorb-Esteve, Aitana; García-Ayllón, María-Salud; Sáez-Valero, Javier

    2015-01-01

    In the continuing search for new cerebrospinal fluid (CSF) biomarkers for Alzheimer’s disease (AD), reasonable candidates are the secretase enzymes involved in the processing of the amyloid precursor protein (APP), as well as the large proteolytic cleavage fragments sAPP? and sAPP?. The enzymatic activities of some of these secretases, such as BACE1 and TACE, have been investigated as potential AD biomarkers, and it has been assumed that these activities present in human CSF result from the soluble truncated forms of the membrane-bound enzymes. However, we and others recently identified soluble forms of BACE1 and APP in CSF containing the intracellular domains, as well as the multi-pass transmembrane presenilin-1 (PS1) and other subunits of ?-secretase. We also review recent findings that suggest that most of these soluble transmembrane proteins could display self-association properties based on hydrophobic and/or ionic interactions leading to the formation of heteromeric complexes. The oligomerization state of these potential new biomarkers needs to be taken into consideration for assessing their real potential as CSF biomarkers for AD by adequate molecular tools. PMID:26082753

  15. Amyloid-? suppresses AMP-activated protein kinase (AMPK) signaling and contributes to ?-synuclein-induced cytotoxicity.

    Science.gov (United States)

    Lin, Chih-Li; Cheng, Yu-Shih; Li, Hsin-Hua; Chiu, Pai-Yi; Chang, Yen-Ting; Ho, Ying-Jui; Lai, Te-Jen

    2016-01-01

    Dementia with Lewy bodies (DLB) is a neurodegenerative disorder caused by abnormal accumulation of Lewy bodies, which are intracellular deposits composed primarily of aggregated ?-synuclein (?Syn). Although ?Syn has been strongly implicated to induce neurotoxicity, overexpression of wild-type ?Syn is shown to be insufficient to trigger formation of protein aggregates by itself. Therefore, investigating the possible mechanism underlying ?Syn aggregation is essential to understand the pathogenesis of DLB. Previous studies have demonstrated that amyloid ? (A?), the primary cause of Alzheimer's disease (AD), may promote the formation of ?Syn inclusion bodies. However, it remains unclear how A? contributes to the deposition and neurotoxicity of ?Syn. In the present study, we investigated the cytotoxic effects of A? in ?Syn-overexpressed neuronal cells. Our results showed that A? inhibits autophagy and enhances ?Syn aggregation in ?Syn-overexpressed cells. Moreover, A? also reduced sirtuin 1 (Sirt1) and its downstream signaling, resulting in increased intracellular ROS accumulation and mitochondrial dysfunction. Our in vitro and in vivo studies support that A?-inhibition of AMP-activated protein kinase (AMPK) signaling is involved in the neurotoxic effects of ?Syn. Taken together, our findings suggest that A? plays a synergistic role in ?Syn aggregation and cytotoxicity, which may provide a novel understanding for exploring the underlying molecular mechanism of DLB. PMID:26515689

  16. 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...

  17. 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.

  18. 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

  19. 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.

  20. Characterizing the location and trafficking routes of the neuronal retromer and its role in amyloid precursor protein transport

    OpenAIRE

    Bhalla, Akhil; Vetanovetz, Christopher P.; Morel, Etienne; Chamoun, Zeina; Paolo, Gilbert Di; Small, Scott A

    2012-01-01

    The retromer complex plays an important role in intracellular transport, is highly expressed in the hippocampus, and has been implicated in the trafficking of the amyloid precursor protein (APP). Nevertheless, the trafficking routes of the neuronal retromer and the role it plays in APP transport in neuronal processes remains unknown. Here we use hippocampal neuronal cultures to address these issues. Using fluorescence microscopy, we find that Vps35, the core element of the retromer complex, i...

  1. 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...

  2. Histone Deacetylase Inhibitor Valproic Acid Inhibits Cancer Cell Proliferation via Down-regulation of the Alzheimer Amyloid Precursor Protein*

    OpenAIRE

    Venkataramani, Vivek; Rossner, Christian; Iffland, Lara; SCHWEYER, STEFAN; Tamboli, Irfan Y.; Walter, Jochen; Wirths, Oliver; Bayer, Thomas A.

    2010-01-01

    The ?-amyloid precursor protein (APP) represents a type I transmembrane glycoprotein that is ubiquitously expressed. In the brain, it is a key player in the molecular pathogenesis of Alzheimer disease. Its physiological function is however less well understood. Previous studies showed that APP is up-regulated in prostate, colon, pancreatic tumor, and oral squamous cell carcinoma. In this study, we show that APP has an essential role in growth control of pancreatic and colon cancer. Abundant A...

  3. 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...

  4. 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.

  5. Highly increased CSF tau protein and decreased ?-amyloid (1-42) in sporadic CJD: a discrimination from Alzheimer's disease?

    Science.gov (United States)

    Kapaki, E; Kilidireas, K; Paraskevas, G; Michalopoulou, M; Patsouris, E

    2001-01-01

    The aim was to quantify tau protein and ?-amyloid (A?42) in the CSF of patients with sporadic Creutzfeldt-Jakob disease (CJD), Alzheimer's disease (AD), and controls. Double sandwich enzyme linked immunosorbent assays (ELISAs) were used for measurments. Tau was increased 58-fold in CJD and 3.5-fold in AD compared with controls, whereas A?42 was decreased 0.5-fold in both CJD and AD. A cut off level for tau protein at 2131 pg/ml successfully discriminated CJD from AD (100% specificity and 93% sensitivity). Tau protein concentration in CSF is probably an additional useful marker in differentiating CJD from AD.?? PMID:11511720

  6. 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.

  7. 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

  8. 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...

  9. 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.

  10. 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-macroglob......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...... 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....

  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. 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

  13. Solid-state NMR analysis of the ?-strand orientation of the protofibrils of amyloid ?-protein

    International Nuclear Information System (INIS)

    Highlights: ? The supramolecular structure of A?42 protofibrils was analyzed by solid-state NMR. ? The Ala-21 residue in the A?42 protofibrils is included in a slightly disordered ?-strand. ? The A?42 protofibrils do not form intermolecular in-register parallel ?-sheets. -- Abstract: Alzheimer’s disease (AD) is caused by abnormal deposition (fibrillation) of a 42-residue amyloid ?-protein (A?42) in the brain. During the process of fibrillation, the A?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?42 protofibrils, the intermolecular proximity of the Ala-21 residues in the A?42 protofibrils was analyzed by 13C–13C rotational resonance experiments in the solid state. Unlike the A?42 fibrils, an intermolecular 13C–13C correlation was not found in the A?42 protofibrils. This result suggests that the ?-strands of the A?42 protofibrils are not in an in-register parallel orientation. A?42 monomers would assemble to form protofibrils with the ?-strand conformation, then transform into fibrils by forming intermolecular parallel ?-sheets.

  14. 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

  15. 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.

  16. Influence of disease process and duration on acute phase proteins in serum and peritoneal fluid of horses with colic

    DEFF Research Database (Denmark)

    Pihl, Tina Holberg; Scheepers, E.; Sanz, M.; Goddard, A.; Page, P.; Toft, N.; Andersen, Pia Haubro; Jacobsen, Stine

    2015-01-01

    Background: The acute phase proteins (APP) serum amyloid A (SAA), haptoglobin, and ?brinogen are valuable blood bi-omarkers in equine in?ammatory diseases, but knowledge of factors in?uencing their concentrations in blood and peritoneal?uid (PF) of horses with colic is needed. Objectives: The...... (WBC) in horses with colic admitted to 2 referral hospitals. Animals: The study included 367 horses with colic admitted at 2 referral hospitals. Methods: Prospective multicenter observational study of clinical data, as well as blood and PF biomarkers. Associationsbetween biomarker concentrations and...... clinical variables were analyzed using multivariate linear regression analysis. Results: Increasing pre-admission duration of colic was associated with increased concentrations of APP in blood andPF. Blood concentrations of SAA and ?brinogen were associated with disease process (in?ammatory, strangulations...

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. 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...

  5. 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-...

  6. 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...

  7. Immunoassay for serum amyloid A using a glassy carbon electrode modified with carboxy-polypyrrole, multiwalled carbon nanotubes, ionic liquid and chitosan

    International Nuclear Information System (INIS)

    We report on a highly sensitive electrochemical immunoassay for the serum inflammation marker amyloid A (SAA). It is making use of a glassy carbon electrode that was modified with carboxy-endcapped polypyrrole (PPy-?-COOH), multiwalled carbon nanotubes (MWCNTs), ionic liquid and chitosan acting as the support platform. The nanocomposite increases the sensitivity and stability of the assay. Antibody against SAA was immobilized on a monolayer surface consisting of PPy-?-COOH. The electrode material was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry. The calibration plot for this assay, when operated at 0.16 V (vs. SCE) and applied to spiked serum samples, is linear in the 0.001 to 900 ng mL?1 SAA concentration range, and the detection limit is as low as 0.3 pg mL?1 (at an S/N ratio of 3). The electrode is stable and highly sensitive. The detection scheme is likely to be applicable to numerous other kinds of immunoassays. (author)

  8. 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

  9. 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

  10. 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.

  11. 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

  12. Amyloid misfolding, aggregation, and the early onset of protein deposition diseases: insights from AFM experiments and computational analyses

    Directory of Open Access Journals (Sweden)

    Yuri L. Lyubchenko

    2015-05-01

    Full Text Available The development of Alzheimer's disease is believed to be caused by the assembly of amyloid ? proteins into aggregates and the formation of extracellular senile plaques. Similar models suggest that structural misfolding and aggregation of proteins are associated with the early onset of diseases such as Parkinson's, Huntington's, and other protein deposition diseases. Initially, the aggregates were structurally characterized by traditional techniques such as x-ray crystallography, NMR, electron microscopy, and AFM. However, data regarding the structures formed during the early stages of the aggregation process were unknown. Experimental models of protein deposition diseases have demonstrated that the small oligomeric species have significant neurotoxicity. This highlights the urgent need to discover the properties of these species, to enable the development of efficient diagnostic and therapeutic strategies. The oligomers exist transiently, making it impossible to use traditional structural techniques to study their characteristics. The recent implementation of single-molecule imaging and probing techniques that are capable of probing transient states have enabled the properties of these oligomers to be characterized. Additionally, powerful computational techniques capable of structurally analyzing oligomers at the atomic level advanced our understanding of the amyloid aggregation problem. This review outlines the progress in AFM experimental studies and computational analyses with a primary focus on understanding the very first stage of the aggregation process. Experimental approaches can aid in the development of novel sensitive diagnostic and preventive strategies for protein deposition diseases, and several examples of these approaches will be discussed.

  13. 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)

  14. 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.)

  15. Transcranial laser therapy alters amyloid precursor protein processing and improves mitochondrial function in a mouse model of Alzheimer's disease

    Science.gov (United States)

    McCarthy, Thomas; Yu, Jin; El-Amouri, Salim; Gattoni-Celli, Sebastiano; Richieri, Steve; De Taboada, Luis; Streeter, Jackson; Kindy, Mark S.

    2011-03-01

    Transcranial laser therapy (TLT) using a near-infrared energy laser system was tested in the 2x Tg amyloid precursor protein (APP) mouse model of Alzheimer's Disease (AD). TLT was administered 3 times/week at escalating doses, starting at 3 months of age, and was compared to a control group which received no laser treatment. Treatment sessions were continued for a total of six months. The brains were examined for amyloid plaque burden, A? peptides (A?1-40 and A?1-42 ), APP cleavage products (sAPP?, CTF?) and mitochondrial activity. Administration of TLT was associated with a significant, dose-dependent reduction in amyloid load as indicated by the numbers of A? plaques. Levels of A?1-40 and A?1-42 levels were likewise reduced in a dose-dependent fashion. All TLT doses produced an increase in brain sAPP? and a decrease in CTF? levels consistent with an increase in ?-secretase activity and a decrease in ?-secretase activity. In addition, TLT increased ATP levels and oxygen utilization in treated animals suggesting improved mitochondrial function. These studies suggest that TLT is a potential candidate for treatment of AD.

  16. Altered temporal patterns of anxiety in aged and amyloid precursor protein (APP) transgenic mice.

    Science.gov (United States)

    Bedrosian, Tracy A; Herring, Kamillya L; Weil, Zachary M; Nelson, Randy J

    2011-07-12

    Both normal aging and dementia are associated with dysregulation of the biological clock, which contributes to disrupted circadian organization of physiology and behavior. Diminished circadian organization in conjunction with the loss of cholinergic input to the cortex likely contributes to impaired cognition and behavior. One especially notable and relatively common circadian disturbance among the aged is "sundowning syndrome," which is characterized by exacerbated anxiety, agitation, locomotor activity, and delirium during the hours before bedtime. Sundowning has been reported in both dementia patients and cognitively intact elderly individuals living in institutions; however, little is known about temporal patterns in anxiety and agitation, and the neurobiological basis of these rhythms remains unspecified. In the present study, we explored the diurnal pattern of anxiety-like behavior in aged and amyloid precursor protein (APP) transgenic mice. We then attempted to treat the observed behavioral disturbances in the aged mice using chronic nightly melatonin treatment. Finally, we tested the hypothesis that time-of-day differences in acetylcholinesterase and choline acetyltransferase expression and general neuronal activation (i.e., c-Fos expression) coincide with the behavioral symptoms. Our results show a temporal pattern of anxiety-like behavior that emerges in elderly mice. This behavioral pattern coincides with elevated locomotor activity relative to adult mice near the end of the dark phase, and with time-dependent changes in basal forebrain acetylcholinesterase expression. Transgenic APP mice show a similar behavioral phenomenon that is not observed among age-matched wild-type mice. These results may have useful applications to the study and treatment of age- and dementia-related circadian behavioral disturbances, namely, sundowning syndrome. PMID:21709248

  17. 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

  18. Development of transgenic rats producing human ?-amyloid precursor protein as a model for Alzheimer's disease: Transgene and endogenous APP genes are regulated tissue-specifically

    Directory of Open Access Journals (Sweden)

    Chan Anthony WS

    2008-02-01

    Full Text Available Abstract Background Alzheimer's disease (AD is a devastating neurodegenerative disorder that affects a large and growing number of elderly individuals. In addition to idiopathic disease, AD is also associated with autosomal dominant inheritance, which causes a familial form of AD (FAD. Some instances of FAD have been linked to mutations in the ?-amyloid protein precursor (APP. Although there are numerous mouse AD models available, few rat AD models, which have several advantages over mice, have been generated. Results Fischer 344 rats expressing human APP driven by the ubiquitin-C promoter were generated via lentiviral vector infection of Fischer 344 zygotes. We generated two separate APP-transgenic rat lines, APP21 and APP31. Serum levels of human amyloid-beta (A?40 were 298 pg/ml for hemizygous and 486 pg/ml for homozygous APP21 animals. Serum A?42 levels in APP21 homozygous rats were 135 pg/ml. Immunohistochemistry in brain showed that the human APP transgene was expressed in neurons, but not in glial cells. These findings were consistent with independent examination of enhanced green fluorescent protein (eGFP in the brains of eGFP-transgenic rats. APP21 and APP31 rats expressed 7.5- and 3-times more APP mRNA, respectively, than did wild-type rats. Northern blots showed that the human APP transgene, driven by the ubiquitin-C promoter, is expressed significantly more in brain, kidney and lung compared to heart and liver. A similar expression pattern was also seen for the endogenous rat APP. The unexpected similarity in the tissue-specific expression patterns of endogenous rat APP and transgenic human APP mRNAs suggests regulatory elements within the cDNA sequence of APP. Conclusion This manuscript describes the generation of APP-transgenic inbred Fischer 344 rats. These are the first human AD model rat lines generated by lentiviral infection. The APP21 rat line expresses high levels of human APP and could be a useful model for AD. Tissue-specific expression in the two transgenic rat lines and in wild-type rats contradicts our current understanding of APP gene regulation. Determination of the elements that are responsible for tissue-specific expression of APP may enable new treatment options for AD.

  19. Serum concentrations of lipopolysaccharide activity-modulating proteins during tuberculosis.

    Science.gov (United States)

    Juffermans, N P; Verbon, A; van Deventer, S J; Buurman, W A; van Deutekom, H; Speelman, P; van der Poll, T

    1998-12-01

    Lipopolysaccharide (LPS) is the principal stimulator of host defense against gram-negative bacteria. LPS-binding protein (LBP), bactericidal/permeability-increasing protein (BPI), and soluble CD14 (sCD14) bind LPS and regulate its toxicity. Lipoarabinomannan, a cell wall component of Mycobacterium tuberculosis, resembles LPS with respect to induction of inflammatory responses through recognition by LBP and sCD14. LBP, BPI, and sCD14 were measured in serum of 124 patients with tuberculosis in various stages of disease, in persons who had been in close contact with patients with contagious pulmonary tuberculosis, and in healthy controls. Levels of these LPS toxicity-regulating proteins were elevated in patients with active tuberculosis compared with those in contacts and controls and declined during treatment. The levels of LBP and sCD14 were higher in patients with fever and anorexia. LPS-regulating proteins may play a role in host defense during tuberculosis, presumably through interaction with lipoarabinomannan. PMID:9815247

  20. Study on the Elution of the Adsorbed Serum Proteins on Biphasic Calcium Phosphate Ceramics

    Directory of Open Access Journals (Sweden)

    WANG Jing, CHEN Ying, ZHU Xiang-Dong, FAN Yu-Jiang, ZHANG Xing-Dong

    2013-10-01

    Full Text Available Two types of porous BCP ceramics were fabricated, using human serum as the model of protein solution. The effect of the different eluants and porous structure on the elution of the adsorbed serum proteins on BCP ceramics were investigated. The results showed that 400 mmol/L Na3PO4 solution had higher elution efficiency for the adsorbed serum proteins on BCP ceramics than 2 mol/L NaCl or 2% sodium dodecycl sufonate (SDS solution. Moreover, the porous structure of BCP ceramics had a strong impact on the elution of the adsorbed serum proteins. The microporous structure could promote the adsorption of serum proteins on BCP ceramics and slowed down their release rate, but the 3D interconnected macropores were favorable for the elution and release of serum proteins from the BCP surface.

  1. The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Mallory, E-mail: m.gough1@lancaster.ac.uk; Blanthorn-Hazell, Sophee, E-mail: s.blanthorn-hazell@lancaster.ac.uk; Delury, Craig, E-mail: c.delury@lancaster.ac.uk; Parkin, Edward, E-mail: e.parkin@lancaster.ac.uk

    2014-10-31

    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.

  2. 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

  3. 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...

  4. 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?...

  5. Serum transferrin levels in children with protein-energy malnutrition

    Directory of Open Access Journals (Sweden)

    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

  6. The serum protein carbonyl content level in relation to exercise stress test

    OpenAIRE

    Titiporn Mekrungruangwong; Porrnthanate Seenak; Saowanee Luangaram; Tomon Thongsri; Sarawut Kumphune

    2012-01-01

    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 h...

  7. 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

  8. 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

  9. The neuroprotective effect of immune serum of adeno-associated virus vaccine containing A?1-15 gene on amyloid toxicity

    Directory of Open Access Journals (Sweden)

    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.

  10. Protein sorting motifs in the cytoplasmic tail of SorCS1 control generation of Alzheimer's amyloid-? peptide.

    Science.gov (United States)

    Lane, Rachel F; Steele, John W; Cai, Dongming; Ehrlich, Michelle E; Attie, Alan D; Gandy, Sam

    2013-04-17

    Endosomal sorting of the Alzheimer amyloid precursor protein (APP) plays a key role in the biogenesis of the amyloid-? (A?) peptide. Genetic lesions underlying Alzheimer's disease (AD) can act by interfering with this physiological process. Specifically, proteins involved in trafficking between endosomal compartments and the trans-Golgi network (TGN) [including the retromer complex (Vps35, Vps26) and its putative receptors (sortilin, SorL1, SorCS1)] have been implicated in the molecular pathology of late-onset AD. Previously, we demonstrated a role for SorCS1 in APP metabolism and A? production and, while we implicated a role for the retromer in this regulation, the underlying mechanism remained poorly understood. Here, we provide evidence for a motif within the SorCS1c cytoplasmic tail that, when manipulated, results in perturbed sorting of APP and/or its fragments to endosomal compartments, decreased retrograde TGN trafficking, and increased A? production in H4 neuroglioma cells. These perturbations apparently do not involve turnover of the cell surface APP pool, but rather they involve intracellular APP and/or its fragments, downstream of APP endocytosis. PMID:23595767

  11. 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

  12. 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...

  13. 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.

  14. 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 ...

  15. Radioassay of serum vitamin B12 using a competitive protein binding technique

    International Nuclear Information System (INIS)

    A method has been developed for the radioassay of serum vitamin B12 using a competitive binding technique. By this method, vitamin B12 levels as low as 50 pg per ml of serum can be estimated in test samples. Egg yolk has been used as a test binding protein, which has several advantages over serum or plasma protein binding agents, as described in this paper. This binder is quite suitable and reliable for the assay of vitamin B12. (author)

  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. 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

  18. Repeated administration of the noradrenergic neurotoxin N-(2-chloroethyl-N-ethyl-2-bromobenzylamine (DSP-4 modulates neuroinflammation and amyloid plaque load in mice bearing amyloid precursor protein and presenilin-1 mutant transgenes

    Directory of Open Access Journals (Sweden)

    Richardson Jill C

    2007-02-01

    Full Text Available Abstract Background Data indicates anti-oxidant, anti-inflammatory and pro-cognitive properties of noradrenaline and analyses of post-mortem brain of Alzheimer's disease (AD patients reveal major neuronal loss in the noradrenergic locus coeruleus (LC, the main source of CNS noradrenaline (NA. The LC has projections to brain regions vulnerable to amyloid deposition and lack of LC derived NA could play a role in the progression of neuroinflammation in AD. Previous studies reveal that intraperitoneal (IP injection of the noradrenergic neurotoxin N-(2-chloroethyl-N-ethyl-2-bromobenzylamine (DSP-4 can modulate neuroinflammation in amyloid over-expressing mice and in one study, DSP-4 exacerbated existing neurodegeneration. Methods TASTPM mice over-express human APP and beta amyloid protein and show age related cognitive decline and neuroinflammation. In the present studies, 5 month old C57/BL6 and TASTPM mice were injected once monthly for 6 months with a low dose of DSP-4 (5 mg kg-1 or vehicle. At 8 and 11 months of age, mice were tested for cognitive ability and brains were examined for amyloid load and neuroinflammation. Results At 8 months of age there was no difference in LC tyrosine hydroxylase (TH across all groups and cortical NA levels of TASTPM/DSP-4, WT/Vehicle and WT/DSP-4 were similar. NA levels were lowest in TASTPM/Vehicle. Messenger ribonucleic acid (mRNA for various inflammatory markers were significantly increased in TASTPM/Vehicle compared with WT/Vehicle and by 8 months of age DSP-4 treatment modified this by reducing the levels of some of these markers in TASTPM. TASTPM/Vehicle showed increased astrocytosis and a significantly larger area of cortical amyloid plaque compared with TASTPM/DSP-4. However, by 11 months, NA levels were lowest in TASTPM/DSP-4 and there was a significant reduction in LC TH of TASTPM/DSP-4 only. Both TASTPM groups had comparable levels of amyloid, microglial activation and astrocytosis and mRNA for inflammatory markers was similar except for interleukin-1 beta which was increased by DSP-4. TASTPM mice were cognitively impaired at 8 and 11 months but DSP-4 did not modify this. Conclusion These data reveal that a low dose of DSP-4 can have varied effects on the modulation of amyloid plaque deposition and neuroinflammation in TASTPM mice dependent on the duration of dosing.

  19. 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

  20. 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

  1. Dependence pH and proposed mechanism for aggregation of Alzheimer's disease-related amyloid-?(1-42) protein

    Science.gov (United States)

    Kobayashi, Shigeki; Tanaka, Yhuki; Kiyono, Mituhiro; Chino, Masahiro; Chikuma, Toshiyuki; Hoshi, Keiko; Ikeshima, Hideaki

    2015-08-01

    It is shown that the aggregation and oligomerization of ?-amyloid protein (A?1-42) are strongly dependent on solution pH. Ionic forms of the side bands of A?1-42 were generated by adjusting the pH using different buffer solutions. As a result, it was possible to establish a relationship between the aggregation of A?1-42 and the pH. In addition, to gain insight into the mechanism of A?1-42 aggregation, aggregation models for A?17-42 (2-13 mer prepared at pH 7-8) were computed using a MMFF (molecular mechanics) method. When the pH was greater than the isoelectric point (IP) of A?17-42, the aggregation of A?17-42 was accelerated by intermolecular ion bridge relay binding of Asp23 with Lys28. Such binding of Asp23 with Lys28 can explain the high level of stability of A? fibrils and oligomers (plastic-like biopolymers found in the amyloid plaques observed in the brains of patients with Alzheimer's disease) produced as the result of A? aggregation. At pH 9.5, A?1-42 aggregation was not observed experimentally, because the side chain of Lys28 contained unprotonated amino groups (-NH2, not -NH3+). This result was also confirmed using the MMFF method.

  2. 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.

  3. Role of maternal serum Chlamydia trachomatis IgG antibodies and serum C- reactive protein in preterm labour

    Directory of Open Access Journals (Sweden)

    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

  4. Evaluation of three high abundance protein depletion kits for umbilical cord serum proteomics

    Directory of Open Access Journals (Sweden)

    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.

  5. 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...... 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...

  6. 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

  7. 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.

  8. A multi-pathway perspective on protein aggregation: implications for control of the rate and extent of amyloid formation.

    Science.gov (United States)

    Hall, Damien; Kardos, József; Edskes, Herman; Carver, John A; Goto, Yuji

    2015-03-12

    The nucleation-growth model has been used extensively for characterizing in vitro amyloid fibril formation kinetics and for simulating the relationship between amyloid and disease. In the majority of studies amyloid has been considered as the dominant, or sole, aggregation end product, with the presence of other competing non-amyloid aggregation processes, for example amorphous aggregate formation, being largely ignored. Here, we examine possible regulatory effects that off-pathway processes might exert on the rate and extent of amyloid formation - in particular their potential for providing false positives and negatives in the evaluation of anti-amyloidogenic agents. Furthermore, we investigate how such competing reactions might influence the standard interpretation of amyloid aggregation as a two-state system. We conclude by discussing our findings in terms of the general concepts of supersaturation and system metastability - providing some mechanistic insight as to how these empirical phenomena may manifest themselves in the amyloid arena. PMID:25647034

  9. 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.

  10. 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

  11. Systematic studies of the interaction between amyloid beta-protein and lipids

    OpenAIRE

    Song, H

    2005-01-01

    The amyloid peptide (Aß), a normal constituent of neuronal and non-neuronal cells, has been shown to be a major component of the extracellular plaque of Alzheimer’s disease (AD). The interaction of Aß peptides with the lipid matrix of neuronal cell membranes plays an important role in the pathogenesis of AD. In this study, we have developed peptide-tethered artificial lipid membranes by the Langmuir-Blodgett and Langmuir-Schaefer methods. Anti-Aß40-mAb labeled with a fluorophore was used to p...

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. Quantitative Proteomic Analysis of Serum Proteins from Oral Cancer Patients: Comparison of Two Analytical Methods

    Directory of Open Access Journals (Sweden)

    Yan Yang

    2014-08-01

    Full Text Available Serum proteomic analysis can be a valuable approach for the discovery of protein biomarkers for early detection or monitoring of a disease. In this study, two analytical methods were compared for quantification of serum proteins in patients with oral cancer. In the first approach, we quantified serum proteins between oral squamous cell carcinoma (OSCC and healthy control subjects by performing in-solution digestion of serum proteins, isobaric tags for relative and absolute quantification (iTRAQ labeling of the resulting peptides, strong cation exchange (SCX fractionation of labeled peptides and finally capillary liquid chromatography with tandem mass spectrometry (LC-MS/MS analysis of the peptides. In the second approach, we first separated serum proteins with SDS-PAGE. The gel-separated proteins were then digested with trypsin and the resulting peptides were labeled with iTRAQ and analyzed with LC-MS/MS for protein quantification. A total of 319 serum proteins were quantified with the first proteomic approach whereas a total of 281 proteins were quantified by the second proteomic approach. Most of the proteins were identified and quantified by both approaches, suggesting that these methods are similarly effective for serum proteome analysis. This study provides compelling evidence that quantitative serum proteomic analysis of OSCC is a valuable approach for identifying differentially expressed proteins in cancer patients’ circulation systems that may be used as potential biomarkers for disease detection. Further validation in large oral cancer patient populations may lead to a simple and low invasive clinical tool for OSCC diagnosis or monitoring.

  19. 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

  20. 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

  1. 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.

  2. Increased serum levels of mutant p53 proteins in patients with colorectal cancer.

    OpenAIRE

    K. S. SHIM; Kim, K. H.; Park, B. W.; S.Y.Lee; Choi, J. H.; Han, W. S.; Park, E. B.

    1998-01-01

    We have examined the serum levels of the mutant p53 protein in patients with colorectal cancer preoperatively (n=50), and in patients with adenomatous polyp (n=13). Mutant p53 protein in patients after curative surgical resection of colorectal cancer (n=26, part of the fifty preoperative patients) was also measured. Serum samples were stored frozen at -70 degrees C until the time of analysis. We used the p53 mutant ELISA (QIA03, CALBIOCHEM) system. Serum levels of the mutant p53 protein in pa...

  3. Baicalin attenuates alzheimer-like pathological changes and memory deficits induced by amyloid ?1-42 protein.

    Science.gov (United States)

    Chen, Chong; Li, Xiaohong; Gao, Peilong; Tu, Yue; Zhao, Mingliang; Li, Jianwei; Zhang, Sai; Liang, Haiqian

    2015-04-01

    Baicalin is one bioactive flavone with anti-inflammatory and neuroprotective activities. The neuroprotective effects of baicalin on pathological changes and behavioral deficits were explored in a mouse model of amyloid ? (A?)(1-42) protein-induced Alzheimer's disease (AD). Mice received a bilateral injection of A?(1-42) protein into the hippocampus, then they were treated with baicalin (30, 50 and 100 mg/kg body weight, orally) or Tween 80. The therapeutic effects of baicalin were monitored by Morris water maze trial and probe test. Then mice were sacrificed for immunohistochemistry and western blot analysis. After a relatively short-term treatment of 14 days, 100 mg/kg of baicalin significantly ameliorated memory impairment in the Morris water maze test and probe test, and also attenuated glial cell activations and increase of TNF-? and IL-6 expressions induced by A?(1-42) protein. These results suggest that baicalin ameliorated A?(1-42) protein-related pathology and cognitive dysfunction via its anti-neuroinflammatory activity, and may be a potential candidate for the treatment of AD. PMID:25108596

  4. 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...

  5. 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...

  6. 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.

  7. Rhenium and technetium complexes that bind to amyloid-? plaques.

    Science.gov (United States)

    Hayne, David J; North, Andrea J; Fodero-Tavoletti, Michelle; White, Jonathan M; Hung, Lin W; Rigopoulos, Angela; McLean, Catriona A; Adlard, Paul A; Ackermann, Uwe; Tochon-Danguy, Henri; Villemagne, Victor L; Barnham, Kevin J; Donnelly, Paul S

    2015-03-21

    Alzheimer's disease is associated with the presence of insoluble protein deposits in the brain called amyloid plaques. The major constituent of these deposits is aggregated amyloid-? peptide. Technetium-99m complexes that bind to amyloid-? plaques could provide important diagnostic information on amyloid-? plaque burden using Single Photon Emission Computed Tomography (SPECT). Tridentate ligands with a stilbene functional group were used to form complexes with the fac-[M(I)(CO)3](+) (M = Re or (99m)Tc) core. The rhenium carbonyl complexes with tridentate co-ligands that included a stilbene functional group and a dimethylamino substituent bound to amyloid-? present in human frontal cortex brain tissue from subjects with Alzheimer's disease. This chemistry was extended to make the analogous [(99m)Tc(I)(CO)3](+) complexes and the complexes were sufficiently stable in human serum. Whilst the lipophilicity (log?D7.4) of the technetium complexes appeared ideally suited for penetration of the blood-brain barrier, preliminary biodistribution studies in an AD mouse model (APP/PS1) revealed relatively low brain uptake (0.24% ID g(-1) at 2 min post injection). PMID:25515141

  8. 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

  9. 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...

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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 ...

  17. 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 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 (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 ) 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 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.

  18. 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...

  19. Serum C-reactive protein concentrations in early abdominal and pulmonary sepsis

    OpenAIRE

    Orati, Juliane Agustini; Almeida, Patricia; Santos, Vanessa; Ciorla, Gustavo; Lobo, Suzana Margareth

    2013-01-01

    Objectives To evaluate the C-reactive protein serum levels in patients with pulmonary and abdominal sepsis during the first five days of sepsis progression. Methods The present investigation was a retrospective cohort study conducted at the university hospital with 345 patients who were admitted to the intensive care unit and diagnosed with sepsis of pulmonary or abdominal origin. Serum C-reactive protein concentrations were measured by the turbidimetric immunoassay. For analysis of C-reactiv...

  20. 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...

  1. 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...

  2. 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...

  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. 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

  5. Peptide sequences that target proteins to lysosomes for enhanced degradation during serum withdrawal

    International Nuclear Information System (INIS)

    Ribonuclease A (RNase A) microinjected into human diploid fibroblasts is degraded with a half-life of 80-100 h in the presence of serum, but its half-life declines to 40 h when cells are deprived of serum. This increased degradation in response to serum withdrawal results from an increased rate of uptake of microinjected RNase A from the cytosol into lysosomes. The cells' ability to recognize RNase A for this enhanced degradation is based on some feature of amino acids 1-20. Covalent linkage of S-peptide to other proteins results in enhanced lysosomal degradation of the conjugate in response to serum withdrawal. The authors have further defined the essential region of RNase S-peptide to be within residues 7-11, KFERQ. Coinjection of radiolabeled RNase A and excess unlabeled pentapeptide specifically blocks the enhanced degradation of RNase A. Affinity-purified polyclonal IgGs raised against KFERQ immunoprecipitate 25-30% of radiolabeled cytosolic proteins from human fibroblasts. Pulse-chase experiments indicate that these proteins are preferentially degraded upon serum withdrawal while degradation of nonimmuno-precipitated proteins is unaffected. These results suggest that peptide sequences similar to KFERQ are contained within cellular proteins and that such sequences target proteins to lysosomes for enhanced degradation during serum withdrawal

  6. Radioprotective properties of certain nitrogenous compounds heterocyclic on the serum proteins of irradiated mice

    International Nuclear Information System (INIS)

    The results obtained from this study suggest the following: the concentration of total serum proteins in mice is very little changed during all the treatments carried out, while protein fractions showed significant alterations. The concentrations of various serum proteins remain almost constant under normal conditions. Intraperitoneal administration of imidazole or benzimidazole at the mentioned doses induces rapid quantitative changes in the serum which are recovered in about 3 days Whole-body X-irradiation at 750 roentgens creates slow but progressive and persisting serious changes in a concentration of serum protein fractions which end by death of animals at the 8 - 10. day after irradiation. Whole-body X-irradiation of imidazole or benzimidazole protected animals results in quantitative rapid changes in concentration of serum protein fractions, for about four days after which a slow but steady restoration begins. The concentration approaches the normal levels towards the 10. day after irradiation. Imidazole and benzimidazole were proved to be good radio-protectants against the effects of radiation on serum protein fractions. Benzimidazole seems to surpass imidazole. (authors)

  7. Serum C-reactive protein levels predict neurological outcome after aneurysmal subarachnoid hemorrhage

    Directory of Open Access Journals (Sweden)

    Flávio Ramalho Romero

    2012-03-01

    Full Text Available OBJECTIVES: Our aim was to evaluate the relationship between serum C-reactive protein (CRP levels and the neurological prognosis and development of vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH. METHODS: Eighty-two adult patients with aSAH diagnoses were prospectively evaluated. Glasgow Coma Scale (GCS score, Hunt and Hess grade, Fisher grade, cranial CT scans, digital subtraction angiography studies and daily neurological examinations were recorded. Serial serum CRP measurements were obtained daily between admission and the tenth day. Glasgow Outcome Scale (GOS and the modified Rankin Scale (mRS were used to assess the prognosis. RESULTS: Serum CRP levels were related to severity of aSAH. Patients with lower GCS scores and higher Hunt and Hess and Fisher grades presented statistically significant higher serum CRP levels. Patients with higher serum CRP levels had a less favorable prognosis. CONCLUSIONS: Increased serum CRP levels were strongly associated with worse clinical prognosis in this study.

  8. Quantification of gamma-secretase modulation differentiates inhibitor compound selectivity between two substrates Notch and amyloid precursor protein

    Directory of Open Access Journals (Sweden)

    Yang Ting

    2008-11-01

    Full Text Available Abstract Background Deposition of amyloid-β protein (Aβ is a major pathological hallmark of Alzheimer's disease (AD. Aβ is generated from γ-secretase cleavage of amyloid precursor protein (APP. In addition to APP, γ-secretase also cleaves other type I integral membrane proteins, including the Notch receptor, a key molecule involved in embryonic development. Results To explore selective γ-secretase inhibitors, a combination of five methods was used to systematically determine these inhibitors' profiles on the γ-secretase cleavage of APP and Notch. When two potent γ-secretase inhibitors, compound E (cpd E and DAPT, were used in a conventional in vitro γ-secretase activity assay, cpd E completely blocked Aβ generation from the cleavage of substrate APP C100, but only had a minor effect on Notch cleavage and NICD generation. Next, cpd E and DAPT were applied to HEK293 cells expressing a truncated Notch substrate NotchΔE. Both cpd E and DAPT were more potent in blocking Aβ generation than NICD generation. Third, a reporter construct was created that carried the NICD targeting promoter with three Su(H binding sequences followed by the luciferase gene. We found that the inhibition of NICD generation by cpd E and DAPT was consistent with the reduced expression of luciferase gene driven by this Notch targeting promoter. Fourth, levels of "Notch-Aβ-like" (Nβ* peptide derived from two previously reported chimeric APP with its transmembrane domain or the juxtamembrane portion replaced by the Notch sequence were quantified. Measurement of Nβ* peptides by ELISA confirmed that EC50's of cpd E were much higher for Nβ* than Aβ. Finally, the expression levels of Notch target gene her6 in cpd E or DAPT-treated zebrafish were correlated with the degree of tail curvature due to defective somitogenesis, a well characterized Notch phenotype in zebrafish. Conclusion Our ELISA-based quantification of Aβ and Nβ* in combination with the test in zebrafish provides a novel approach for efficient cell-based screening and in vivo validation of APP selective γ-secretase inhibitors.

  9. 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

  10. The Human Disease-Associated A? Amyloid Core Sequence Forms Functional Amyloids in a Fungal Adhesin

    Science.gov (United States)

    Rameau, Rachele D.; Jackson, Desmond N.; Beaussart, Audrey; Dufrêne, Yves F.

    2016-01-01

    ABSTRACT There is increasing evidence that many amyloids in living cells have physiological functions. On the surfaces of fungal cells, amyloid core sequences in adhesins can aggregate into 100- to 1,000-nm-wide patches to form high-avidity adhesion nanodomains on the cell surface. The nanodomains form through interactions that have amyloid-like properties: binding of amyloid dyes, perturbation by antiamyloid agents, and interaction with homologous sequences. To test whether these functional interactions are mediated by typical amyloid interactions, we substituted an amyloid core sequence, LVFFA, from human A? protein for the native sequence IVIVA in the 1,419-residue Candida albicans adhesin Als5p. The chimeric protein formed cell surface nanodomains and mediated cellular aggregation. The native sequence and chimeric adhesins responded similarly to the amyloid dye thioflavin T and to amyloid perturbants. However, unlike the native protein, the nanodomains formed by the chimeric protein were not force activated and formed less-robust aggregates under flow. These results showed the similarity of amyloid interactions in the amyloid core sequences of native Als5p and A?, but they also highlighted emergent properties of the native sequence. Also, a peptide composed of the A? amyloid sequence flanked by amino acids from the adhesin formed two-dimensional sheets with sizes similar to the cell surface patches of the adhesins. These results inform an initial model for the structure of fungal cell surface amyloid nanodomains. PMID:26758179

  11. Pro-Inflammatory S100A8 and S100A9 Proteins: Self-Assembly into Multifunctional Native and Amyloid Complexes

    Directory of Open Access Journals (Sweden)

    Ludmilla A. Morozova-Roche

    2012-03-01

    Full Text Available S100A8 and S100A9 are EF-hand Ca2+ binding proteins belonging to the S100 family. They are abundant in cytosol of phagocytes and play critical roles in numerous cellular processes such as motility and danger signaling by interacting and modulating the activity of target proteins. S100A8 and S100A9 expression levels increased in many types of cancer, neurodegenerative disorders, inflammatory and autoimmune diseases and they are implicated in the numerous disease pathologies. The Ca2+ and Zn2+-binding properties of S100A8/A9 have a pivotal influence on their conformation and oligomerization state, including self-assembly into homo- and heterodimers, tetramers and larger oligomers. Here we review how the unique chemical and conformational properties of individual proteins and their structural plasticity at the quaternary level account for S100A8/A9 functional diversity. Additional functional diversification occurs via non-covalent assembly into oligomeric and fibrillar amyloid complexes discovered in the aging prostate and reproduced in vitro. This process is also regulated by Ca2+and Zn2+-binding and effectively competes with the formation of the native complexes. High intrinsic amyloid-forming capacity of S100A8/A9 proteins may lead to their amyloid depositions in numerous ailments characterized by their elevated expression patterns and have additional pathological significance requiring further thorough investigation.

  12. 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 β-amyloid, the main component in the neuritic plaques found in patients with Alzheimer's disease, is generated by cleavage of the β-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.

  13. Protein Sorting Motifs in the Cytoplasmic Tail of SorCS1 Control Generation of Alzheimer’s Amyloid-? Peptide: Mechanisms for SorCS1 Regulation of A? Generation

    OpenAIRE

    Lane, Rachel F; Steele, John W; Cai, Dongming; Ehrlich, Michelle E; Attie, Alan D.; Gandy, Sam

    2013-01-01

    Endosomal sorting of the Alzheimer amyloid precursor protein (APP) plays a key role in the biogenesis of the amyloid-? peptide (A?). Genetic lesions underlying Alzheimer disease (AD) can act by interfering with this physiological process. Specifically, proteins involved in trafficking between endosomal compartments and the trans Golgi network (TGN) (including the retromer complex (Vps35, Vps26) and its putative receptors (sortilin, SorL1, SorCS1) have been implicated in the molecular patholog...

  14. 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

  15. mGlu5 receptors and cellular prion protein mediate amyloid-?-facilitated synaptic long-term depression in vivo

    Science.gov (United States)

    Hu, Neng-Wei; Nicoll, Andrew J.; Zhang, Dainan; Mably, Alexandra J.; O’Malley, Tiernan; Purro, Silvia A.; Terry, Cassandra; Collinge, John; Walsh, Dominic M.; Rowan, Michael J.

    2014-01-01

    NMDA-type glutamate receptors (NMDARs) are currently regarded as paramount in the potent and selective disruption of synaptic plasticity by Alzheimer’s disease amyloid ?-protein (A?). Non-NMDAR mechanisms remain relatively unexplored. Here we describe how A? facilitates NMDAR-independent long-term depression of synaptic transmission in the hippocampus in vivo. Synthetic A? and A? in soluble extracts of Alzheimer’s disease brain usurp endogenous acetylcholine muscarinic receptor-dependent long-term depression, to enable long-term depression that required metabotropic glutamate-5 receptors (mGlu5Rs). We also find that mGlu5Rs are essential for A?-mediated inhibition of NMDAR-dependent long-term potentiation in vivo. Blocking A? binding to cellular prion protein with antibodies prevents the facilitation of long-term depression. Our findings uncover an overarching role for A?-PrPC-mGlu5R interplay in mediating both LTD facilitation and LTP inhibition, encompassing NMDAR-mediated processes that were previously considered primary. PMID:24594908

  16. 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

  17. 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.

  18. 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

  19. Candida albicans Shaving to Profile Human Serum Proteins on Hyphal Surface

    Science.gov (United States)

    Marín, Elvira; Parra-Giraldo, Claudia M.; Hernández-Haro, Carolina; Hernáez, María L.; Nombela, César; Monteoliva, Lucía; Gil, Concha

    2015-01-01

    Candida albicans is a human opportunistic fungus and it is responsible for a wide variety of infections, either superficial or systemic. C. albicans is a polymorphic fungus and its ability to switch between yeast and hyphae is essential for its virulence. Once C. albicans obtains access to the human body, the host serum constitutes a complex environment of interaction with C. albicans cell surface in bloodstream. To draw a comprehensive picture of this relevant step in host-pathogen interaction during invasive candidiasis, we have optimized a gel-free shaving proteomic strategy to identify both, human serum proteins coating C. albicans cells and fungi surface proteins simultaneously. This approach was carried out with normal serum (NS) and heat inactivated serum (HIS). We identified 214 human and 372 C. albicans unique proteins. Proteins identified in C. albicans included 147 which were described as located at the cell surface and 52 that were described as immunogenic. Interestingly, among these C. albicans proteins, we identified 23 GPI-anchored proteins, Gpd2 and Pra1, which are involved in complement system evasion and 7 other proteins that are able to attach plasminogen to C. albicans surface (Adh1, Eno1, Fba1, Pgk1, Tdh3, Tef1, and Tsa1). Furthermore, 12 proteins identified at the C. albicans hyphae surface induced with 10% human serum were not detected in other hypha-induced conditions. The most abundant human proteins identified are involved in complement and coagulation pathways. Remarkably, with this strategy, all main proteins belonging to complement cascades were identified on the C. albicans surface. Moreover, we identified immunoglobulins, cytoskeletal proteins, metabolic proteins such as apolipoproteins and others. Additionally, we identified more inhibitors of complement and coagulation pathways, some of them serpin proteins (serine protease inhibitors), in HIS vs. NS. On the other hand, we detected a higher amount of C3 at the C. albicans surface in NS than in HIS, as validated by immunofluorescence. PMID:26696967

  20. Embryo culture in teratological surveillance and serum proteins in development. Progress report, 1977--1978. [Rats, chickens

    Energy Technology Data Exchange (ETDEWEB)

    Klein, N.W.

    1978-07-01

    Studies were conducted on two established teratogens, cadmium and cyclophosphamide, and four substances related to energy technology, coal solid, spent shale particulates, shale oil, and coal oil. Rat embryos were cultured on serum from animals injected with teratogens. Studies were also conducted on regulation of serum protein synthesis using endoderm cell cultures from chick embryos and cell-free synthesis of serum proteins. (HLW)

  1. 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...

  2. 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

  3. 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...

  4. 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...

  5. 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

  6. Axonal Injury in Young Pediatric Head Trauma: A Comparison Study of ?-amyloid Precursor Protein (?-APP) Immunohistochemical Staining in Traumatic and Nontraumatic Deaths*

    OpenAIRE

    Johnson, Michael W.; Stoll, Lisa; Rubio, Ana; Troncoso, Juan; PLETNIKOVA, OLGA; Fowler, David R.; Ling LI

    2011-01-01

    We tested the independent utility of ? amyloid precursor protein (? APP) immunohistochemical staining as evidence of brain trauma in the deaths of young children. Blinded reviewers retrospectively reviewed immunostained brain tissues from homicidal deaths, age matched control cases without evidence of trauma, as well as cases of sudden infant death syndrome (SIDS). The reviewers correctly identified five of the seven cases with documented inflicted head trauma. However, one of seven age match...

  7. Antigenic specificity of serum antibodies in mice fed soy protein

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Bruun, S.W.; Frøkiær, Hanne

    2003-01-01

    Background: Soybean protein is used in a number of food products but unfortunately is also a common cause of food allergy. Upon ingestion of soy protein, healthy mice like other animals and humans generate a soy-specific antibody response in the absence of signs of illness. Not much is known about...... the relationship between the immunogenic proteins involved in this nondeleterious antibody response and the pathological response associated with food allergy. The objective of the present study was to characterize the antigenic specificity of the soy protein-specific antibody response generated in...... healthy mice ingesting soy protein. Methods: Blood from mice fed a soy-containing diet was analyzed using ELISA and immunoblot for antibody reactivity towards various soy protein fractions and pure soy proteins/subunits. Mice bred on a soy-free diet were used as controls. Results: The detectable antigenic...

  8. 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.

  9. Neuroanatomical localization and quantification of amyloid precursor protein mRNA by in situ hybridization in the brains of normal, aneuploid, and lesioned mice

    International Nuclear Information System (INIS)

    Amyloid precursor protein mRNA was localized in frozen sections from normal and experimentally lesioned adult mouse brain and from normal and aneuploid fetal mouse brain by in situ hybridization with a 35S-labeled mouse cDNA probe. The highest levels of hybridization in adult brain were associated with neurons, primarily in telencephalic structures. The dense labeling associated with hippocampal pyramidal cells was reduced significantly when the cells were eliminated by injection of the neurotoxin ibotenic acid but was not affected when electrolytic lesions were placed in the medial septum. Since the gene encoding amyloid precursor protein has been localized to mouse chromosome 16, the authors also examined the expression of this gene in the brains of mouse embryos with trisomy 16 and trisomy 19 at 15 days of gestation. RNA gel blot analysis and in situ hybridization showed a marked increase in amyloid precursor protein mRNA in the trisomy 16 mouse head and brain when compared with euploid littermates or with trisomy 19 mice

  10. UV-radiation effect on physico-chemical properties of plasma proteins and blood serum in donors

    International Nuclear Information System (INIS)

    Comparative analysis of changes in chromatographic behaviour and viscosity of separate fractions of proteins after UV irradiation (240-390 nm) of donor blood plasma and serum detected a lower photosensitivity of blood plasma as compared with blood serum

  11. 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 

  12. 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

  13. 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 αA. 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.

  14. 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.

  15. Identification of a Compound That Disrupts Binding of Amyloid-? to the Prion Protein Using a Novel Fluorescence-based Assay*

    Science.gov (United States)

    Risse, Emmanuel; Nicoll, Andrew J.; Taylor, William A.; Wright, Daniel; Badoni, Mayank; Yang, Xiaofan; Farrow, Mark A.; Collinge, John

    2015-01-01

    The prion protein (PrP) has been implicated both in prion diseases such as Creutzfeldt-Jakob disease, where its monomeric cellular isoform (PrPC) is recruited into pathogenic self-propagating polymers of misfolded protein, and in Alzheimer disease, where PrPC may act as a receptor for synaptotoxic oligomeric forms of amyloid-? (A?). There has been considerable interest in identification of compounds that bind to PrPC, stabilizing its native fold and thereby acting as pharmacological chaperones to block prion propagation and pathogenesis. However, compounds binding PrPC could also inhibit the binding of toxic A? species and may have a role in treating Alzheimer disease, a highly prevalent dementia for which there are currently no disease-modifying treatments. However, the absence of a unitary, readily measurable, physiological function of PrP makes screening for ligands challenging, and the highly heterogeneous nature of A? oligomer preparations makes conventional competition binding assays difficult to interpret. We have therefore developed a high-throughput screen that utilizes site-specifically fluorescently labeled protein to identify compounds that bind to PrP and inhibit both A? binding and prion propagation. Following a screen of 1,200 approved drugs, we identified Chicago Sky Blue 6B as the first small molecule PrP ligand capable of inhibiting A? binding, demonstrating the feasibility of development of drugs to block this interaction. The interaction of Chicago Sky Blue 6B was characterized by isothermal titration calorimetry, and its ability to inhibit A? binding and reduce prion levels was established in cell-based assays. PMID:25995455

  16. Potent influence of bovine serum proteins in experimental dendritic cell-based vaccination protocols

    DEFF Research Database (Denmark)

    Toldbod, Helle; Agger, R; Bolund, L; Hokland, M

    2003-01-01

    Typically autologous dendritic cells (DCs) intended for vaccination are generated from bone marrow derived stem cells or blood monocytes, loaded with antigen and introduced into the organism. However, addition of serum to DC culture medium is often necessary. Thus, serum proteins will be taken up...... addition of fetal calf serum (FCS) to the medium for culturing murine DCs. The results showed that vaccination of mice with DCs cultured in vitro in the presence of FCS but in the absence of extraneous tumour antigens, protected the mice from challenge with B16 tumour cells similarly cultured in FCS. This...... protection could not be elicited by vaccination with FCS alone. Interestingly, the protective effect of DC vaccination was abolished when the challenging B16 tumour cells were free of serum proteins. Thus, these results show that DCs grown in the presence of FCS are able to induce immunity, which may be...

  17. Amyloid ?-Protein Assembly and Alzheimer's Disease: Dodecamers of A?42, but Not of A?40, Seed Fibril Formation.

    Science.gov (United States)

    Economou, Nicholas J; Giammona, Maxwell J; Do, Thanh D; Zheng, Xueyun; Teplow, David B; Buratto, Steven K; Bowers, Michael T

    2016-02-17

    Evidence suggests that oligomers of the 42-residue form of the amyloid ?-protein (A?), A?42, play a critical role in the etiology of Alzheimer's disease (AD). Here we use high resolution atomic force microscopy to directly image populations of small oligomers of A?42 that occur at the earliest stages of aggregation. We observe features that can be attributed to a monomer and to relatively small oligomers, including dimers, hexamers, and dodecamers. We discovered that A?42 hexamers and dodecamers quickly become the dominant oligomers after peptide solubilization, even at low (1 ?M) concentrations and short (5 min) incubation times. Soon after (?10 min), dodecamers are observed to seed the formation of extended, linear preprotofibrillar ?-sheet structures. The preprotofibrils are a single A?42 layer in height and can extend several hundred nanometers in length. To our knowledge this is the first report of structures of this type. In each instance the preprotofibril is associated off center with a single layer of a dodecamer. Protofibril formation continues at longer times, but is accompanied by the formation of large, globular aggregates. A?40, by contrast, does not significantly form the hexamer or dodecamer but instead produces a mixture of smaller oligomers. These species lead to the formation of a branched chain-like network rather than discrete structures. PMID:26839237

  18. 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.

  19. 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

  20. The Kunitz-protease inhibitor domain in amyloid precursor protein reduces cellular mitochondrial enzymes expression and function.

    Science.gov (United States)

    Chua, Li-Min; Lim, Mei-Li; Wong, Boon-Seng

    2013-08-01

    Mitochondrial dysfunction is a prominent feature of Alzheimer's disease (AD) and this can be contributed by aberrant metabolic enzyme function. But, the mechanism causing this enzymatic impairment is unclear. Amyloid precursor protein (APP) is known to be alternatively spliced to produce three major isoforms in the brain (APP695, APP751, APP770). Both APP770 and APP751 contain the Kunitz Protease Inhibitory (KPI) domain, but the former also contain an extra OX-2 domain. APP695 on the other hand, lacks both domains. In AD, up-regulation of the KPI-containing APP isoforms has been reported. But the functional contribution of this elevation is unclear. In the present study, we have expressed and compared the effect of the non-KPI containing APP695 and the KPI-containing APP751 on mitochondrial function. We found that the KPI-containing APP751 significantly decreased the expression of three major mitochondrial metabolic enzymes; citrate synthase, succinate dehydrogenase and cytochrome c oxidase (COX IV). This reduction lowers the NAD(+)/NADH ratio, COX IV activity and mitochondrial membrane potential. Overall, this study demonstrated that up-regulation of the KPI-containing APP isoforms is likely to contribute to the impairment of metabolic enzymes and mitochondrial function in AD. PMID:23872114

  1. 4'-Chlorodiazepam is neuroprotective against amyloid-beta through the modulation of survivin and bax protein expression in vitro.

    Science.gov (United States)

    Arbo, B D; Marques, C V; Ruiz-Palmero, I; Ortiz-Rodriguez, A; Ghorbanpoor, S; Arevalo, M A; Garcia-Segura, L M; Ribeiro, M F

    2016-02-01

    The translocator protein of 18kDa (TSPO) is located in the outer mitochondrial membrane and is involved in the cholesterol transport into the mitochondria and in the regulation of steroidogenesis, mitochondrial permeability transition pore opening and apoptosis. TSPO ligands have been investigated as therapeutic agents that promote neuroprotective effects in experimental models of brain injury and neurodegenerative diseases. The aim of this study was to identify the neuroprotective effects of 4'-chlorodiazepam (4'-CD), a ligand of TSPO, against amyloid-beta (A?) in SHSY-5Y neuroblastoma cells and its mechanisms of action. A? decreased the viability of SHSY-5Y neuroblastoma cells, while 4'-CD had a neuroprotective effect at the doses of 1nM and 10nM. The neuroprotective effects of 4'-CD against A? were associated with the inhibition of A?-induced upregulation of Bax and downregulation of survivin. In summary, our findings indicate that 4'-CD is neuroprotective against A?-induced neurotoxicity by a mechanism that may involve the regulation of Bax and survivin expression. PMID:26707976

  2. 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.

  3. 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.

  4. Amyloid protein-mediated differential DNA methylation status regulates gene expression in Alzheimer's disease model cell line

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Hye Youn; Choi, Eun Nam [Department of Biochemistry, School of Medicine, Ewha Womans University, 911-1 Mok-6-dong, Yangcheon-ku, Seoul 158-710 (Korea, Republic of); Ahn Jo, Sangmee [Department of Pharmacy, College of Pharmacy, Dankook University, San 29 Anseo-dong, Dongnam-gu, Cheonan-si, Chungnam 330-714 (Korea, Republic of); Oh, Seikwan [Department of Neuroscience and TIDRC, School of Medicine, Ewha Womans University, 911-1 Mok-6-dong, Yangcheon-ku, Seoul 158-710 (Korea, Republic of); Ahn, Jung-Hyuck, E-mail: ahnj@ewha.ac.kr [Department of Biochemistry, School of Medicine, Ewha Womans University, 911-1 Mok-6-dong, Yangcheon-ku, Seoul 158-710 (Korea, Republic of)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Genome-wide DNA methylation pattern in Alzheimer's disease model cell line. Black-Right-Pointing-Pointer Integrated analysis of CpG methylation and mRNA expression profiles. Black-Right-Pointing-Pointer Identify three Swedish mutant target genes; CTIF, NXT2 and DDR2 gene. Black-Right-Pointing-Pointer 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 Prime -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.

  5. 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.

  6. The presence of antibodies to oxidative modified proteins in serum from polycystic ovary syndrome patients.

    Science.gov (United States)

    Palacio, J R; Iborra, A; Ulcova-Gallova, Z; Badia, R; Martínez, P

    2006-05-01

    Polycystic ovary syndrome (PCOS) affects 5-10% of women of reproductive age. Free radicals, as a product of oxidative stress, impair cells and tissue properties related to human fertility. These free radicals, together with the oxidized molecules, may have a cytotoxic or deleterious effects on sperm and oocytes, on early embryo development or on the endometrium. Aldehyde-modified proteins are highly immunogenic and circulating autoantibodies to new epitopes, such as malondialdehyde (MDA), may affect the reproductive system. Autoantibodies or elevated reactive oxygen species (ROS) in serum are often associated with inflammatory response. The purpose of this work is to investigate whether PCOS women show increased levels of oxidized proteins (protein-MDA) and anti-endometrial antibodies (AEA) in their sera, compared with control patients, and to determine whether AEA specificity is related to oxidized protein derivatives. Sera from 31 women [10 patients with PCOS (PCOS group) and 21 women with male factor of infertility (control group)] were chosen from patients attending for infertility. Anti-endometrial antibodies were determined by enzyme-linked immunosorbent assay (ELISA) with an endometrial cell line (RL-95). Antibodies against MDA modified human serum albumin (HSA-MDA) were also determined by ELISA. Oxidized proteins (protein-MDA) in serum were determined by a colorimetric assay. Patients with PCOS have significantly higher levels of AEA and anti-HSA-MDA, as well as oxidized proteins (protein-MDA) in serum than control patients. For the first time, we describe an autoimmune response in PCOS patients, in terms of AEA. The evidence of protein-MDA in the serum of these patients, together with the increased antibody reactivity to MDA-modified proteins (HSA-MDA) in vitro, supports the conclusion that oxidative stress may be one of the important causes for abnormal endometrial environment with poor embryo receptivity in PCOS patients. PMID:16634794

  7. 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...

  8. Blood eosinophils and serum eosinophil cationic protein in patients with acute and chronic urticaria

    OpenAIRE

    Di Lorenzo, G; Mansueto, P; Melluso, M.; Candore, G; Cigna, D.; Pellitteri, M. E.; A. Di Salvo; Caruso, C.

    1996-01-01

    We have analysed the relationship of blood eosinophil count and serum eosinophil cationic protein (ECP) levels in patients with acute and chronic idiopathic urticaria. The ECP levels and eosinophil counts were measured in the peripheral blood of 15 patients with acute urticaria, 25 with chronic idiopathic urticaria and 10 normal healthy subjects. Blood eosinophil counts and serum ECP levels increased in all patients with acute urticaria. Concerning patients affected by chronic urticaria, taki...

  9. Serum C-reactive protein levels predict neurological outcome after aneurysmal subarachnoid hemorrhage

    OpenAIRE

    Flávio Ramalho Romero; Eduardo de Freitas Bertolini; Figueiredo, Eberval G; Manoel Jacobsen Teixeira

    2012-01-01

    OBJECTIVES: Our aim was to evaluate the relationship between serum C-reactive protein (CRP) levels and the neurological prognosis and development of vasospasm in patients with aneurysmal subarachnoid hemorrhage (aSAH). METHODS: Eighty-two adult patients with aSAH diagnoses were prospectively evaluated. Glasgow Coma Scale (GCS) score, Hunt and Hess grade, Fisher grade, cranial CT scans, digital subtraction angiography studies and daily neurological examinations were recorded. Serial serum CRP ...

  10. 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.

  11. 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...

  12. 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

  13. Changes in astrocyte functional markers and ?-amyloid metabolism-related proteins in the early stages of hypercholesterolemia.

    Science.gov (United States)

    Chen, Y L; Wang, L M; Chen, Y; Gao, J Y; Marshall, C; Cai, Z Y; Hu, G; Xiao, M

    2016-03-01

    Cholesterol is an essential substance for maintaining normal structure and function of the brain. But unfortunately, a long-term high-cholesterol diet can lead to a variety of pathological changes of the brain such as ?-amyloid (A?) accumulation, Tau hyperphosphorylation, reactive gliosis, neuroinflammation, neuronal death and synaptic degeneration. These pathological changes have complex internal relations with one other, causing memory impairment and participating in the pathogenesis of Alzheimer's disease (AD). However, early hypercholesterolemia-induced events that lead to brain deterioration are not clear. To address this, 6-month-old female mice were fed a 3% cholesterol diet for 8weeks, followed by behavioral, biochemical and neuropathological analyses. The high-cholesterol-fed mice did not show neuronal and synaptic impairment or cognitive deficits compared with mice given a normal diet, but astrocytes were mildly activated with increased expression of functional markers including apolipoprotein E and aquaporin 4 in the hippocampus. Hippocampal interleukin-1? expression slightly increased, but interleukin-6 (IL-6) and tumor necrosis factor-? did not change significantly compared with those in the control group. Levels of A?, and its precursor protein, were unaffected, but levels of presenilin 1 and insulin-degrading enzyme (IDE), that initiate A? generation and degradation, respectively, increased in the hippocampus of the model mice. In addition, Tau phosphorylation levels were not different between the control and model groups. These results suggest that changes in astrocyte functional markers and A? metabolism proteins, which contribute to maintaining brain cholesterol and A? homeostasis, are early events in the process of hypercholesterolemia-related neuropathological changes. PMID:26724580

  14. 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.

  15. An Investigation on the Blood-Serum Proteins of Chalcides ocellatus (Sauria: Scincidae) Populations from Southern Anatolia

    OpenAIRE

    Hüseyin ARIKAN; ATATÜR, Mehmet K.; MERMER, Ahmet

    1998-01-01

    In this study, blood-serum proteins of 22 adult (11 MM , 11 VV ) Chalcides ocellatus (ocelated skink) specimens collected from various localities in Southern Anatolia are investigated qualitatively and quantitatively by means of polyacrylamide disc electrophoresis and densitometry. The species' serum protein electropherograms and protein distribution patterns are established for the first time.

  16. Fetzima (levomilnacipran), a drug for major depressive disorder as a dual inhibitor for human serotonin transporters and beta-site amyloid precursor protein cleaving enzyme-1.

    Science.gov (United States)

    Rizvi, Syed Mohd Danish; Shaikh, Sibhghatulla; Khan, Mahiuddin; Biswas, Deboshree; Hameed, Nida; Shakil, Shazi

    2014-01-01

    Pharmacological management of Major Depressive Disorder includes the use of serotonin reuptake inhibitors which targets serotonin transporters (SERT) to increase the synaptic concentrations of serotonin. Beta-site amyloid precursor protein cleaving enzyme-1 (BACE-1) is responsible for amyloid ? plaque formation. Hence it is an interesting target for Alzheimer's disease (AD) therapy. This study describes molecular interactions of a new Food and Drug Administration approved antidepressant drug named 'Fetzima' with BACE-1 and SERT. Fetzima is chemically known as levomilnacipran. The study has explored a possible link between the treatment of Depression and AD. 'Autodock 4.2' was used for docking study. The free energy of binding (?G) values for 'levomilnacipran-SERT' interaction and 'levomilnacipran-BACE1' interaction were found to be -7.47 and -8.25 kcal/mol, respectively. Levomilnacipran was found to interact with S438, known to be the most important amino acid residue of serotonin binding site of SERT during 'levomilnacipran-SERT' interaction. In the case of 'levomilnacipran-BACE1' interaction, levomilnacipran interacted with two very crucial aspartic acid residues of BACE-1, namely, D32 and D228. These residues are accountable for the cleavage of amyloid precursor protein and the subsequent formation of amyloid ? plaques in AD brain. Hence, Fetzima (levomilnacipran) might act as a potent dual inhibitor of SERT and BACE-1 and expected to form the basis of a future dual therapy against depression and AD. It is an established fact that development of AD is associated with Major Depressive Disorder. Therefore, the design of new BACE-1 inhibitors based on antidepressant drug scaffolds would be particularly beneficial. PMID:25345508

  17. 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.

  18. Metabolism of homologous and heterologous serum proteins in garter snakes (Thamnophis ordinoides)

    International Nuclear Information System (INIS)

    The half-life (Tsub(1/2) of serum immunoglobulin (Ig) and albumin from snakes and mammals were determined in both garter snakes (Thamnophis ordinoides) and mice (Mus musculus). Metabolism of serum proteins in snakes was similar to mammalian protein metabolism in that homologous serum albumin had shorter Tsub(1/2) (16 days) than IgG (38 days). Also, reptilian and mammalian serum proteins had a relatively longer Tsub(1/2) when injected into closely related species. Thus mammalian serum Ig (rabbit gamma globulin (RGG)) had a shorter Tsub(1/2) (6.3 days) in snake than did homologous snake IgG (38 days), whereas in mice, RGG had a longer Tsub(1/2) (3.8 days) than snake Ig (0.9 days). Differences between metabolism of homologous and heterologous albumins were apparent only in snakes in which the Tsub(1/2) of homologous albumin was approximately 8-fold greater than mammalian albumin. These results indicate that metabolism of both Ig and albumin in snakes is regulated by specific receptors whereas albumin receptors have been difficult to demonstrate in mammals. The results of this study suggest that one of the factors determining the metabolism of a protein is its foreignness to the host perhaps because of receptor cross reactions. (author)

  19. 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...

  20. 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.