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Sample records for serum amyloid protein

  1. Induction of hepatic synthesis of serum amyloid A protein and actin.

    Morrow, J F; Stearman, R S; Peltzman, C G; Potter, D. A.

    1981-01-01

    Major changes in the mRNA population of murine liver occur after administration of bacterial lipopolysaccharide, an agent that causes increases in the concentrations of acute-phase serum proteins. The mRNA for one of these, serum amyloid A, is increased at least 500-fold compared to the normal level. It becomes one of the most abundant hepatic mRNAs, and serum amyloid A synthesis comprises about 2.5% of total hepatic protein synthesis in the acute-phase response. Its synthesis is tissue-speci...

  2. Discovery and identification of Serum Amyloid A protein elevated in lung cancer serum

    DAI SongWei; WANG XiaoMin; LIU LiYun; LIU JiFu; WU ShanShan; HUANG LingYun; XIAO XueYuan; HE DaCheng

    2007-01-01

    Two hundred and eighteen serum samples from 175 lung cancer patients and 43 healthy individuals were analyzed by using Surface Enhaced Laser Desorption/lonization Time of Flight Mass Spectrometry (SELDI-TOF-MS). The data analyzed by both Biomarker WizardTM and Biomarker PatternsTM software showed that a protein peak with the molecular weight of 11.6 kDa significantly increased in lung cancer.Meanwhile, the level of this biomarker was progressively increased with the clinical stages of lung cancer. The candidate biomarker was then obtained from tricine one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis by matching the molecular weight with peaks on WCX2 chips and was identified as Serum Amyloid A protein (SAA) by MALDI/MS-MS and database searching. It was further validated in the same serum samples by immunoprecipitation with commercial SAA antibody.To confirm the SAA differential expression in lung cancer patients, the same set of serum samples was measured by ELISA assay. The result showed that at the cutoff point 0.446 (OD value) on the Receiver Operating Characteristic (ROC) curve, SAA could better discriminate lung cancer from healthy individuals with sensitivity of 84.1% and specificity of 80%. These findings demonstrated that SAA could be characterized as a biomarker related to pathological stages of lung cancer.

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

    Christensen, Michelle Brønniche; Langhorn, Rebecca; Goddard, Amelia;

    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...

  4. Examination of Serum Amyloid A Protein in Kidney Transplant Patients : Comparison of Serum Amyloid A and C-Reactive Protein for Mani to ring the Occurrence of Renal-allograft-related Complications

    Fukuda, Yasuhiko; Kanbe, Masayuki; Sumimoto, Ryo; Yoneya, Taiko; Takeshita, Takenori; Hoshino, Shuji; Shintaku, Sadanori; Dohi, Kiyohiko

    1998-01-01

    Serum amyloid A (SAA) is an inflammation -reactive protein, like C-reactive protein (CRP). In this study, we examined SAA levels in the sera of kidney transplant patients with acute rejection (N=12), chronic rejection (N=60) and cytomegalovirus (CMV) infection complications and compared them with serum CRP levels in terms of sensitivity and reactivity. The SAA and CRP showed almost similar kinetics in 10 patients within 2 months of kidney transplantation. However, in 2 patients SAA responded ...

  5. Calcium-dependent and -independent binding of the pentraxin serum amyloid P component to glycosaminoglycans and amyloid proteins

    Danielsen, B; Sørensen, I J; Nybo, Mads; Nielsen, E H; Kaplan, B; Svehag, S E

    1997-01-01

    beta2M) by ELISA. An increase in the dose-dependent binding of SAP to heparan sulfate, AA-protein and beta2M was observed as the pH decreased from 8.0 to 5.0. Furthermore, a lower, but significant Ca2(+)-independent binding of SAP to heparan sulfate, dermatan sulfate, AA protein and the amyloid...

  6. Serum amyloid A: An acute-phase protein involved in tumour pathogenesis

    Sodin-Semrl, S.; Kovacevic, A.

    2016-01-01

    The synthesis of acute-phase protein serum amyloid A (SAA) is largely regulated by inflammation-associated cytokines and a high concentration of circulating SAA may represent an ideal marker for acute and chronic inflammatory diseases. However, SAA is also synthesized in extrahepatic tissues, e.g. human carcinoma metastases and cancer cell lines. An increasing body of in vitro data supports the concept of involvement of SAA in carcinogenesis and neoplastic diseases. Accumulating evidence suggests that SAA might be included in a group of biomarkers to detect a pattern of physiological events that reflect the growth of malignancy and host response. This review is meant to provide a broad overview of the many ways that SAA could contribute to tumour development, and accelerate tumour progression and metastasis, and to gain a better understanding of this acute-phase reactant as a possible link between chronic inflammation and neoplasia. PMID:18726069

  7. Identification of Human Serum Proteins Which Interact With Alzheimer`s Amyloid �A4 Protein

    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.

  8. Extrahepatic production of acute phase serum amyloid A

    Upragarin, N.; Landman, W.J.M.; Gaastra, W; Gruys, E.

    2005-01-01

    Amyloidosis is a group of diseases characterized by the extracellular deposition of protein that contains non-branching, straight fibrils on electron microscopy (amyloid fibrils) that have a high content of ß-pleated sheet conformation. Various biochemically distinct proteins can undergo transformation into amyloid fibrils. The precursor protein of amyloid protein A (AA) is the acute phase protein serum amyloid A (SAA). The concentration of SAA in plasma increa...

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

    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...

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

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

    2011-01-01

    Full Text Available 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 samples were collected after confirmation of clinical and subclinical mastitis by somatic cell count and bacterial identification. Serum haptoglobin (Hp, serum amyloid A (SAA, total sialic acid (TSA, lipid bound sialic acid (LBSA and protein bound sialic acid (PBSA were measured by validated standard methods. Haptoglobin and SAA increased significantly in both types of mastitis compared with control group (P<0.001. However, the ratio of HP/SAA was significantly different from the control group only in clinical mastitis. The results showed that TSA and LBSA were significantly different in control group compared with clinical and subclinical mastitis (P<0.001. Protein bound sialic acid did not change in subclinical mastitis in comparison with control group (P=0.86. There was positive correlation between LBSA and PBSA in clinical mastitis (r=0.72, P=0.02 whereas significant negative correlation was observed between LBSA and PBSA in subclinical mastitis (r=-0.62, P<0.001. Results also showed no correlation between Hp and SAA with each other or with any other parameters in study groups.

  11. Serum amyloid A and C-reactive protein levels may predict microalbuminuria and macroalbuminuria in newly diagnosed type 1 diabetic patients

    Overgaard, Anne Julie; McGuire, James N; Hovind, Peter;

    2012-01-01

    In this study we evaluated the association of baseline levels of six different candidate proteins for the development of microalbuminuria and macroalbuminuria in type 1 diabetic patients, who were followed for approximately 30years. Two of the proteins are markers of inflammation: serum amyloid A...

  12. Calumenin interacts with serum amyloid P component

    Vorum, H; Jacobsen, Christian; Honoré, Bent

    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. After application of a placental tissue extract we were able to elute one protein that interacts with...... calumenin in the presence of Ca(2+). Amino acid sequencing identified this protein as serum amyloid P component (SAP). Furthermore, we verified and characterized the calumenin-SAP interaction by the surface plasmon resonance technique. The findings indicate that calumenin may participate in the...

  13. STIMULATED PLATELETS RELEASE AMYLOID β–PROTEIN PRECURSOR

    Cole, Gregory M.; Galasko, Douglas; Shapiro, I. Paul; Saitoh, Tsunao

    1990-01-01

    Human platelets can be stimulated by thrombin or ionomycin to secrete soluble truncated amyloid β–protein precursor and particulate membrane fragments which contain C-terminal and N-terminal immunoreactive amyloid β–protein precursor. This suggests a possible circulating source of β–protein in serum which may play a role in the formation of amyloid deposits. The release of soluble amyloid β-protein precursor could be involved in normal platelet physiology.

  14. Effects of Ramadan Fasting on Serum Amyloid A and Protein Carbonyl Group Levels in Patients With Cardiovascular Diseases

    Asadi, Hami; Abolfathi, Ali Akbar; Badalzadeh, Reza; Majidinia, Maryam; Yaghoubi, Alireza; Asadi, Maryam; Yousefi, Bahman

    2015-01-01

    Introduction: Serum amyloid-A (SAA) and protein carbonyl group are rigorously related with cardiovascular diseases (CVDs) as a sensitive marker of an acute inflammatory state and as an important index of oxidative stress, respectively. Moreover, diet is one of the main factors that can modify cardiovascular risks. Therefore, this study aimed to investigate the effects of Ramadan fasting on SAA and protein carbonyl group levels in patients with CVDs. Methods: Twenty-one patients (21 male; mean age 52±9 years old) with CVDs (coronary artery disease, cerebrovascular, or peripheral arterial diseases) were participated in this study. Biochemical parameters were measured in patients 2 days before and 2 days after Ramadan fasting. SAA levels were assessed using enzyme-linked immunosorbent assay and Cayman’s protein carbonyl colorimetric assay was provided for measuring protein carbonyl groups. Results: According to the findings of the study, post-Ramadan levels of inflammatory biomarker, SAA was decreased significantly in patients with CVDs in comparison with the baseline before-fasting values (16.84±8.20 vs. 24.40±6.72 μg/ml, P = 0.021). In addition, Ramadan fasting significantly reduced the levels of protein carbonyl group in patients as compared with those of baseline values (33.08±15.31 vs. 43.65±16.88 nmol/ml, P = 0.039). Conclusion: Ramadan fasting has impressive effects on modulating CVDs by decreasing inflammation and oxidative stress markers. However, to get a clear conclusion with more results, further investigation is warranted. PMID:26191392

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

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

    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...... rocket immunoelectrophoresis and electron microscopy. Thus, electron micrographs of purified SAP showed a predominance of decamers. However, the decamer form of SAP reversed to single pentamers when purified SAP was incorporated into SAP-depleted serum....

  16. CRP and SAA1 Haplotypes Are Associated with Both C-Reactive Protein and Serum Amyloid A Levels: Role of Suppression Effects

    Ko, Yu-Lin; Hsu, Lung-An; Wu, Semon; Teng, Ming-Sheng; Chou, Hsin-Hua

    2016-01-01

    To test the statistical association of the CRP and SAA1 locus variants with their corresponding circulating levels and metabolic and inflammatory biomarker levels by using mediation analysis, a sample population of 599 Taiwanese subjects was enrolled and five CRP and four SAA1 variants were genotyped. Correlation analysis revealed that C-reactive protein (CRP) and serum amyloid A (SAA) levels were significantly associated with multiple metabolic phenotypes and inflammatory marker levels. Our ...

  17. Effects of Ramadan Fasting on Serum Amyloid A and Protein Carbonyl Group Levels in Patients With Cardiovascular Diseases

    Asadi Hami

    2015-06-01

    Full Text Available Introduction: Serum amyloid-A (SAA and protein carbonyl group are rigorously related with cardiovascular diseases (CVDs as a sensitive marker of an acute inflammatory state and as an important index of oxidative stress, respectively. Moreover, diet is one of the main factors that canmodify cardiovascular risks. Therefore, this study aimed to investigate the effects of Ramadanfasting on SAA and protein carbonyl group levels in patients with CVDs.Methods: Twenty-one patients (21 male; mean age 52±9 years old with CVDs (coronaryartery disease, cerebrovascular, or peripheral arterial diseases were participated in this study.Biochemical parameters were measured in patients 2 days before and 2 days after Ramadanfasting. SAA levels were assessed using enzyme-linked immunosorbent assay and Cayman’sprotein carbonyl colorimetric assay was provided for measuring protein carbonyl groups.Results: According to the findings of the study, post-Ramadan levels of inflammatory biomarker,SAA was decreased significantly in patients with CVDs in comparison with the baseline beforefastingvalues (16.84±8.20 vs. 24.40±6.72 μg/ml, P = 0.021. In addition, Ramadan fastingsignificantly reduced the levels of protein carbonyl group in patients as compared with those ofbaseline values (33.08±15.31 vs. 43.65±16.88 nmol/ml, P = 0.039.Conclusion: Ramadan fasting has impressive effects on modulating CVDs by decreasinginflammation and oxidative stress markers. However, to get a clear conclusion with more results,further investigation is warranted.

  18. Acute-phase protein serum amyloid A3 is a novel paracrine coupling factor that controls bone homeostasis.

    Thaler, Roman; Sturmlechner, Ines; Spitzer, Silvia; Riester, Scott M; Rumpler, Monika; Zwerina, Jochen; Klaushofer, Klaus; van Wijnen, Andre J; Varga, Franz

    2015-04-01

    Serum amyloid A (A-SAA/Saa3) was shown before to affect osteoblastic metabolism. Here, using RT-quantitative PCR and/or immunoblotting, we show that expression of mouse Saa3 and human SAA1 and SAA2 positively correlates with increased cellular maturation toward the osteocyte phenotype. Expression is not detected in C3H10T1/2 embryonic fibroblasts but is successively higher in preosteoblastic MC3T3-E1 cells, late osteoblastic MLO-A5 cells, and MLO-Y4 osteocytes, consistent with findings using primary bone cells from newborn mouse calvaria. Recombinant Saa3 protein functionally inhibits osteoblast differentiation as reflected by reductions in the expression of osteoblast markers and decreased mineralization in newborn mouse calvaria. Yet, Saa3 protein enhances osteoclastogenesis in mouse macrophages/monocytes based on the number of multinucleated and tartrate-resistant alkaline phosphatase-positive cells and Calcr mRNA expression. Depletion of Saa3 in MLO osteocytes results in the loss of the mature osteocyte phenotype. Recombinant osteocalcin, which is reciprocally regulated with Saa3 at the osteoblast/osteocyte transition, attenuates Saa3 expression in MLO-Y4 osteocytes. Mechanistically, Saa3 produced by MLO-Y4 osteocytes is integrated into the extracellular matrix of MC3T3-E1 osteoblasts, where it associates with the P2 purinergic receptor P2rx7 to stimulate Mmp13 expression via the P2rx7/MAPK/ERK/activator protein 1 axis. Our data suggest that Saa3 may function as an important coupling factor in bone development and homeostasis. PMID:25491310

  19. Serum insulin-like growth factor-I, iron, C-reactive protein, and serum amyloid A for prediction of outcome in dogs with pyometra.

    Jitpean, Supranee; Holst, Bodil Ström; Höglund, Odd V; Pettersson, Ann; Olsson, Ulf; Strage, Emma; Södersten, Fredrik; Hagman, Ragnvi

    2014-07-01

    Pyometra, accumulation of pus in the uterus, is a bacterial infection that frequently initiates systemic inflammation. The disease may have lethal consequences when the systemic effects are severe or complications occur. Markers for identifying high-risk patients and predicting outcome are therefore in high demand. The objective of this study was to measure serum concentrations of insulin-like growth factor-I (IGF-I), iron, C-reactive protein (CRP), and serum amyloid A (SAA) in bitches with pyometra and to explore the possible value of these variables for detection of increased morbidity. In total, 31 bitches were diagnosed with pyometra and destined for surgical treatment (ovariohysterectomy) and 17 healthy bitches were included in the study. Concentrations of IGF-I and iron were lower in the pyometra group (mean concentration 221.2 ± 22.5 ng/mL and 16.9 ± 1.6 μmol/L, respectively) compared with the healthy control group (mean concentration 366.7 ± 46.2 ng/mL and 38.1 ± 2.7 μmol/L, respectively). In contrast, concentrations of CRP and SAA were significantly higher in bitches with pyometra (mean concentrations 212.9 ± 17.3 mg/L and 119.9 ± 8.5 mg/L, respectively) compared with the control group (pyometra, whereas SAA and CRP concentrations were increased in the disease. Although unspecific, measurement of these variables may be valuable as adjunctive markers for prognosis in cases of pyometra. PMID:24661434

  20. Acute-phase protein serum amyloid A3 is a novel paracrine coupling factor that controls bone homeostasis

    Thaler, Roman; Sturmlechner, Ines; Spitzer, Silvia; Riester, Scott M; Rumpler, Monika; Zwerina, Jochen; Klaushofer, Klaus; van Wijnen, Andre J; Varga, Franz

    2014-01-01

    Serum amyloid A (A-SAA/Saa3) was shown before to affect osteoblastic metabolism. Here, using RT-quantitative PCR and/or immunoblotting, we show that expression of mouse Saa3 and human SAA1 and SAA2 positively correlates with increased cellular maturation toward the osteocyte phenotype. Expression is not detected in C3H10T1/2 embryonic fibroblasts but is successively higher in preosteoblastic MC3T3-E1 cells, late osteoblastic MLO-A5 cells, and MLO-Y4 osteocytes, consistent with findings using ...

  1. Serum amyloid P inhibits dermal wound healing

    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 ...

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

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

  3. The role of fibronectin in the development of experimental amyloidosis. Evidence of immunohistochemical codistribution and binding property with serum amyloid protein A.

    Kawahara, E; Shiroo, M; Nakanishi, I.; Migita, S.

    1989-01-01

    Azocasein-induced amyloid A (AA) amyloidosis in CBA/K1Jms mice was investigated to elucidate a preference of serum amyloid A (SAA) deposition in the spleen. By indirect immunofluorescence using anti-SAA/AA antibodies the initial deposition of SAA/AA was recognized in the marginal zone of spleen at 20 days after azocasein injection. Indirect immunofluorescence using anti-fibronectin antibodies also showed meshwork positivity in the corresponding area more intensely than that in controls. Immun...

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

    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...... 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...

  5. Effects of Dexmedetomidine on Postoperative Cognitive Dysfunction and Serum Levels of b-Amyloid and Neuronal Microtubule-Associated Protein in Orthotopic Liver Transplantation Patients.

    Xu, Guang; Li, Lan-Lan; Sun, Zhen-Tao; Zhang, Wei; Han, Xue-Ping

    2016-01-01

    BACKGROUND Because of the restricted data available on patients with postoperative cognitive dysfunction (POCD) in orthotopic liver transplantation (OLT), the goal of our study was to determine the outcome of dexmedetomidine (DEX) on POCD and the mechanism operating in OLT patients. MATERIAL AND METHODS Our study included 80 patients randomly divided into 2 equal groups: the DEX group and the control group. In the DEX group, our patients received an initial dose of DEX at 1 µg/kg for 10 min followed by a continuous infusion at 0.3 µg/kg/h until the end of surgery. The control group received a saline treatment, and neurological tests were performed to assess the status of POCD. Serum level of b-amyloid protein (Aβ) and neuronal microtubule-associated protein (Tau) were measured at designated time points: at pre-operation (T1), 0.5 h after the anhepatic phase (T2), 2 h after the reperfusion of the new liver (T3), at the completion of operation (T4), at day 1 (T5), and at day 7 (T6) after the operation. RESULTS The incidence of POCD was significantly reduced in the DEX group (P=0.017). The score from the neurological tests was significantly decreased in the control group after the operation, but no statistical difference was observed in the DEX group. The DEX groups demonstrated a lower level of β-amyloid and Tau protein than those at the corresponding time points (T4~T6) in the control group (PTau protein may have contributed to this favorable outcome. PMID:27527391

  6. Designing peptidic inhibitors of serum amyloid A aggregation process.

    Sosnowska, Marta; Skibiszewska, Sandra; Kamińska, Emilia; Wieczerzak, Ewa; Jankowska, Elżbieta

    2016-04-01

    Amyloid A amyloidosis is a life-threatening complication of a wide range of chronic inflammatory, infectious and neoplastic diseases, and the most common form of systemic amyloidosis worldwide. It is characterized by extracellular tissue deposition of fibrils that are composed of fragments of serum amyloid A protein (SAA), a major acute-phase reactant protein, produced predominantly by hepatocytes. Currently, there are no approved therapeutic agents directed against the formation of fibrillar SAA assemblies. We attempted to develop peptidic inhibitors based on their similarity and complementarity to the regions critical for SAA self-association, which they should interact with and block their assembly into amyloid fibrils. Inh1 and inh4 which are comprised of the residues from the amyloidogenic region of SAA1.1 protein and Aβ peptide, respectively, were found by us as capable to significantly suppress aggregation of the SAA1-12 peptide. It was chosen as an aggregation model that mimicks the amyloidogenic nucleus of SAA protein. We suppose that aromatic interactions may be responsible for inhibitory activity of both compounds. We also recognized that aromatic residues are involved in self-association of SAA1-12. PMID:26759015

  7. The Correlations Between Concentrations of Myeloperoxidase, Serum Amyloid-A Protein and Scretory Phospolipase A-2 with Proinflammatory HDL in Healthy Male Person

    Marita Kaniawati

    2009-04-01

    Full Text Available BACKGROUND: Low-HDL cholesterol is a risk factor of CAD. Although levels of HDLC are within normal limit in some patients, they suffer CAD. These normal HDL-C levels might become pro-inflammatoric. This study is to measure the correlations between myeloperoxidase (MPO, serum amyloid-A (SAA protein, and secretoryphospholipase-A2 (sPLA2 with inflammatory status of HDL-C. METHODS: This was a cross-sectional study recruited 49 subjects with high HDL-C (>40 mg/dL and 31 subjects with low HDL-C (p<40 mg/dL. HDL-C was determined into antiinflammatory and proinflammatory based on levels of Apo A-1 and hs-CRP. Concentrations of MPO, SAA and s-PLA2 were measured by ELISA method. Levels of Apo A-1 was determined by immunoturbidimetric method. Multiple logistic regression analysis was done using inflammatory status of HDL-C as dependent variables and levels of MPO, SAA, sPLA2, ages, total cholesterol and triglycerides as independent variables. RESULTS: Patient’s age was 43.4+8.3 year, HDL-C was 43.1+9.5 mg/dL, Apo A-1 was 128.3+21.5 mg/dL, hs-CRP was 1.92+3.0 mg/dL. Concentrations of MPO, SAA and sPLA2 successively were 63.2+16.9 ng/mL, 7015.6+5021.1 ng/mL and 1340.2+406.3 pg/mL. Multiple logistic regression analysis showed that SAA is an independent predictor of pro-inflammatory status of HDL-C in high HDL-C group with prevalence ratio of 11.74 (95% CI: 2.51-54.84; p=0.002. In contrast, MPO and sPLA2 were not independent predictor with PR of 1.26 (95% CI: 0.30-5.23; p=0.75 and of 0.94 (95% CI: 0.23-3.91; p=0.93. CONCLUSIONS: SAA is an independent predictor of pro-inflammatory HDL-C even in subjects with high HDL-C. KEYWORDS: atherosclerosis, Apo A-1, serum amyloid A protein, secretory phospholipase A2, myeloperoxidase.

  8. CRP and SAA1 Haplotypes Are Associated with Both C-Reactive Protein and Serum Amyloid A Levels: Role of Suppression Effects

    Yu-Lin Ko

    2016-01-01

    Full Text Available To test the statistical association of the CRP and SAA1 locus variants with their corresponding circulating levels and metabolic and inflammatory biomarker levels by using mediation analysis, a sample population of 599 Taiwanese subjects was enrolled and five CRP and four SAA1 variants were genotyped. Correlation analysis revealed that C-reactive protein (CRP and serum amyloid A (SAA levels were significantly associated with multiple metabolic phenotypes and inflammatory marker levels. Our data further revealed a significant association of CRP and SAA1 variants with both CRP and SAA levels. Mediation analysis revealed that SAA levels suppressed the association between SAA1 genotypes/haplotypes and CRP levels and that CRP levels suppressed the association between CRP haplotypes and SAA levels. In conclusion, genetic variants at the CRP and SAA1 loci independently affect both CRP and SAA levels, and their respective circulating levels act as suppressors. These results provided further evidence of the role of the suppression effect in biological science and may partially explain the missing heritability in genetic association studies.

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

    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 γ-rays (0.55 Gy min-1) and demonstrate dose- and time-dependent changes in blood of C-reactive protein (CRP), serum amyloid A (SAA), and interleukin 6 (IL-6) measured by enzyme linked immunosorbent assay (ELISA). CRP and SAA dose-response results are consistent with ∼1 Gy and ∼0.2 Gy thresholds for photon-exposure at 24 h after TBI, respectively. Highly significant elevations of CRP and SAA (p = 0.00017 and p = 0.0024, respectively) were found in animal plasma at 6 h after all TBI doses suggesting their potential use as early-phase biodosimeters. Results also show that the dynamics and content of CRP and SAA levels reflect the course and severity of the acute radiation sickness (ARS) and may function as prognostic indicators of ARS outcome. These results demonstrate proof-of-concept that these radiation-responsive proteins show promise as a complementary approach to conventional biodosimetry for early assessment of radiation exposures and may also contribute as diagnostic indices in the medical management of radiation accidents.

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

    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.

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

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

    2015-08-01

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

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

    S. S. Biswal; Das, S; Balasubramanian, S.; D. N. Mohanty; K. Sethy; Dasgupta, M.

    2014-01-01

    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 a...

  13. Protein Polymers and Amyloids

    Risør, Michael Wulff

    2014-01-01

    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...... 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 α1AT folding or in the native state represents a therapeutic strategy to prevent polymerization. Using Molecular Dynamics simulations, we identified...

  14. Serum Amyloid A (SAA): a Novel Biomarker for Endometrial Cancer

    Cocco, Emiliano; Bellone, Stefania; El-Sahwi, Karim; Cargnelutti, Marilisa; Buza, Natalia; Tavassoli, Fattaneh A.; Schwartz, Peter E.; Rutherford, Thomas J.; Pecorelli, Sergio; Santin, Alessandro D.

    2009-01-01

    Background We investigated the expression of Serum-Amyloid-A (SAA) in endometrial endometrioid carcinoma (EEC), and evaluated its potential as a serum biomarker. Methods SAA gene and protein expression levels were evaluated in EEC and normal endometrial tissues (NEC), by real time-PCR, immunohistochemistry (IHC) and flow cytometry. SAA concentration in 194 serum samples from 50 healthy-women, 42 women with benign diseases and 102 patients including 49 grade-1, 38 grade-2 and 15 grade-3 EEC was also studied by a sensitive bead-based-immunoassay. Results SAA gene expression levels were significantly higher in EEC when compared to NEC (mean-copy-number by RT-PCR = 182 vs 1.9; P=0.001). IHC revealed diffuse cytoplasmic SAA protein staining in poorly differentiated EEC tissues. High intracellular levels of SAA were identified in primary EEC cell lines evaluated by flow cytometry and SAA was found to be actively secreted in vitro. SAA concentrations (μg/ml) had medians of 6.0 in normal healthy females and 6.0 in patients with benign disease (P=0.92). In contrast, SAA values in the serum of EEC patients had a median of 23.7 significantly higher than those of the healthy group (P=0.001) and benign group (P=0.001). Patients harboring G3 EEC were found to have SAA concentrations significantly higher than G1/G2 patients. Conclusions SAA is not only a liver-secreted-protein but is also an EEC-cell product. SAA is expressed and actively secreted by G3-EEC and it is present in high concentration in the serum of EEC patients. SAA may represent a novel biomarker for EEC to monitor disease recurrence and response to therapy. PMID:20041483

  15. Noninvasive measurement of fecal calprotectin and serum amyloid A combined with intestinal fatty acid-binding protein in necrotizing enterocolitis.

    Reisinger, K.W.; Zee, D.C. van der; Brouwers, H.A.A.; Kramer, B.W.; Heurn, L.W.E. van; Buurman, W.A.; Derikx, J.P.

    2012-01-01

    BACKGROUND: Diagnosis of necrotizing enterocolitis (NEC), prevalent in premature infants, remains challenging. Enterocyte damage in NEC can be assessed by intestinal fatty acid-binding protein (I-FABP), with a sensitivity of 93% and a specificity of 90%. Numerous markers of inflammation are known, s

  16. Noninvasive measurement of fecal calprotectin and serum amyloid A combined with intestinal fatty acid-binding protein in necrotizing enterocolitis

    Reisinger, Kostan W.; Van der Zee, David C.; Brouwers, Hens A. A.; Kramer, Boris W.; van Heurn, L. W. Ernest; Buurman, Wim A.; Derikx, Joep P. M.

    2012-01-01

    Background: Diagnosis of necrotizing enterocolitis (NEC), prevalent in premature infants, remains challenging. Enterocyte damage in NEC can be assessed by intestinal fatty acid-binding protein (I-FABP), with a sensitivity of 93% and a specificity of 90%. Numerous markers of inflammation are known, s

  17. Colocalization of Serum Amyloid A with Microtubules in Human Coronary Artery Endothelial Cells

    Katja Lakota; Nataša Resnik; Katjuša Mrak-Poljšak; Snežna Sodin-Šemrl; Peter Veranič

    2011-01-01

    Serum amyloid A (SAA) acts as a major acute phase protein and represents a sensitive and accurate marker of inflammation. Besides its hepatic origin, as the main source of serum SAA, this protein is also produced extrahepatically. The mRNA levels of SAA become significantly elevated following proinflammatory stimuli, as well as, are induced through their own positive feedback in human primary coronary artery endothelial cells. However, the intracellular functions of SAA are so far unknown. Co...

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

    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...... 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....

  19. Serum amyloid A1: Structure, function and gene polymorphism.

    Sun, Lei; Ye, Richard D

    2016-05-25

    Inducible expression of serum amyloid A (SAA) is a hallmark of the acute-phase response, which is a conserved reaction of vertebrates to environmental challenges such as tissue injury, infection and surgery. Human SAA1 is encoded by one of the four SAA genes and is the best-characterized SAA protein. Initially known as a major precursor of amyloid A (AA), SAA1 has been found to play an important role in lipid metabolism and contributes to bacterial clearance, the regulation of inflammation and tumor pathogenesis. SAA1 has five polymorphic coding alleles (SAA1.1-SAA1.5) that encode distinct proteins with minor amino acid substitutions. Single nucleotide polymorphism (SNP) has been identified in both the coding and non-coding regions of human SAA1. Despite high levels of sequence homology among these variants, SAA1 polymorphisms have been reported as risk factors of cardiovascular diseases and several types of cancer. A recently solved crystal structure of SAA1.1 reveals a hexameric bundle with each of the SAA1 subunits assuming a 4-helix structure stabilized by the C-terminal tail. Analysis of the native SAA1.1 structure has led to the identification of a competing site for high-density lipoprotein (HDL) and heparin, thus providing the structural basis for a role of heparin and heparan sulfate in the conversion of SAA1 to AA. In this brief review, we compares human SAA1 with other forms of human and mouse SAAs, and discuss how structural and genetic studies of SAA1 have advanced our understanding of the physiological functions of the SAA proteins. PMID:26945629

  20. Protein electrophoresis - serum

    ... this page: //medlineplus.gov/ency/article/003540.htm Protein electrophoresis - serum To use the sharing features on ... JavaScript. This lab test measures the types of protein in the fluid (serum) part of a blood ...

  1. Serum Amyloid A Induces Inflammation, Proliferation and Cell Death in Activated Hepatic Stellate Cells.

    Siegmund, Sören V; Schlosser, Monika; Schildberg, Frank A; Seki, Ekihiro; De Minicis, Samuele; Uchinami, Hiroshi; Kuntzen, Christian; Knolle, Percy A; Strassburg, Christian P; Schwabe, Robert F

    2016-01-01

    Serum amyloid A (SAA) is an evolutionary highly conserved acute phase protein that is predominantly secreted by hepatocytes. However, its role in liver injury and fibrogenesis has not been elucidated so far. In this study, we determined the effects of SAA on hepatic stellate cells (HSCs), the main fibrogenic cell type of the liver. Serum amyloid A potently activated IκB kinase, c-Jun N-terminal kinase (JNK), Erk and Akt and enhanced NF-κB-dependent luciferase activity in primary human and rat HSCs. Serum amyloid A induced the transcription of MCP-1, RANTES and MMP9 in an NF-κB- and JNK-dependent manner. Blockade of NF-κB revealed cytotoxic effects of SAA in primary HSCs with signs of apoptosis such as caspase 3 and PARP cleavage and Annexin V staining. Serum amyloid A induced HSC proliferation, which depended on JNK, Erk and Akt activity. In primary hepatocytes, SAA also activated MAP kinases, but did not induce relevant cell death after NF-κB inhibition. In two models of hepatic fibrogenesis, CCl4 treatment and bile duct ligation, hepatic mRNA levels of SAA1 and SAA3 were strongly increased. In conclusion, SAA may modulate fibrogenic responses in the liver in a positive and negative fashion by inducing inflammation, proliferation and cell death in HSCs. PMID:26937641

  2. NNanomechanical characteristics of proteins and peptides in amyloid

    Boayue, Nya Mehnwolo

    2012-01-01

    ......The understanding of the aggregation of amyloid fibrils is essential as they are linked to a number of diseases such as Alzheimer and Parkston’s disease. Amy- loids from different proteins or peptides have common characteristics such as core β-sheet structure, green birefringence upon binding to Congo red, and fibrillar mor- phology. In this thesis, I report single molecule analysis of TTR105−115 a fragment of transthyretin, a serum and cerebrospinal fluid carrier of ...

  3. Maternal and Cord Blood Levels of Serum Amyloid A, C-Reactive Protein, Tumor Necrosis Factor-α, Interleukin -1β, and Interleukin-8 During and After Delivery

    Luciane Marzzullo Cicarelli

    2005-01-01

    after delivery and try to correlate these proteins with tumor necrosis factor-α, interleukin -1β, and interleukin-8. Acute-phase proteins and cytokines were measured by ELISA in 24 healthy pregnant women undergoing vaginal delivery or Cesarean section. Cord blood samples in addition to maternal blood were collected. SAA and CRP reached the maximum maternal serum levels 24 hours after delivery, while cytokines remained constant over time. SAA and CRP were significantly higher in maternal serum than in newborn's (P<.001 at the moment of delivery. SAA and CRP, regardless of the type of delivery, reproduce the common pattern observed in most inflammatory conditions. Proinflammatory cytokine serum levels do not mirror the increase in SAA and CRP levels.

  4. S100A12 suppresses pro-inflammatory, but not pro-thrombotic functions of serum amyloid A.

    Yuen Ming Chung

    Full Text Available S100A12 is elevated in the circulation in patients with chronic inflammatory diseases and recent studies indicate pleiotropic functions. Serum amyloid A induces monocyte cytokines and tissue factor. S100A12 did not stimulate IL-6, IL-8, IL-1β or TNF-α production by human peripheral blood mononuclear cells but low amounts consistently reduced cytokine mRNA and protein levels induced by serum amyloid A, by ∼49% and ∼46%, respectively. However, S100A12 did not affect serum amyloid A-induced monocyte tissue factor. In marked contrast, LPS-induced cytokines or tissue factor were not suppressed by S100A12. S100A12 did not alter cytokine mRNA stability or the cytokine secretory pathway. S100A12 and serum amyloid A did not appear to form complexes and although they may have common receptors, suppression was unlikely via receptor competition. Serum amyloid A induces cytokines via activation of NF-κB and the MAPK pathways. S100A12 reduced serum amyloid A-, but not LPS-induced ERK1/2 phosphorylation to baseline. It did not affect JNK or p38 phosphorylation or the NF-κB pathway. Reduction in ERK1/2 phosphorylation by S100A12 was unlikely due to changes in intracellular reactive oxygen species, Ca(2+ flux or to recruitment of phosphatases. We suggest that S100A12 may modulate sterile inflammation by blunting pro-inflammatory properties of lipid-poor serum amyloid A deposited in chronic lesions where both proteins are elevated as a consequence of macrophage activation.

  5. Haptoglobin and serum amyloid A in milk from dairy cows with chronic sub-clinical mastitis

    Grönlund, Ulrika; Sandgren, Charlotte; Waller, Karin

    2005-01-01

    New tools are needed to detect chronic sub-clinical mastitis, especially in automatic milking systems. Haptoglobin and serum amyloid A (SAA) are the two most sensitive bovine acute phase proteins, and their concentrations increase in milk from cows with clinical mastitis and in milk from cows with experimentally induced chronic sub-clinical Staphylococcus aureus mastitis. The aim of this study was to further evaluate the potential for haptoglobin and SAA in milk as indicators of chronic sub-c...

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

    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 repor...... steric effects when SAP binds to terminal mannose on oligosaccharides localized close to the sialic acid-binding site of the HA trimer.......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...

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

    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

  8. Isoforms of murine and human serum amyloid P component

    Nybo, Mads; Hackler, R; Kold, B;

    1998-01-01

    affect their number. When the acute-phase response was analysed in three mouse strains, CBA/J and C3H/HeN initially showed seven SAP isoforms in serum and C57BL/6 J three or four. The responses in all three strains peaked at day 2 and were normalized within 14 days. On days 2 and 4, CBA/J and C3H......Isoelectric focusing (IEF) and immunofixation of murine serum amyloid P component (SAP), purified and in serum, showed a distinct and strain-dependent isoform pattern with up to seven bands (pI 5.1-5.7). Neuraminidase treatment caused a shift of the isoforms to more basic pI values, but did not...

  9. Adhesion of human platelets to serum amyloid A.

    Urieli-Shoval, Simcha; Shubinsky, George; Linke, Reinhold P; Fridkin, Mati; Tabi, Israel; Matzner, Yaacov

    2002-02-15

    Serum amyloid A (SAA) is an acute phase reactant, and its level in the blood is elevated to 1000-fold in response of the body to trauma, infection, inflammation, and neoplasia. SAA was reported to inhibit platelet aggregation and to induce adhesion of leukocytes. This study looked at adhesion of human platelets to SAA. Immobilized SAA supported the adhesion of human washed platelets; level of adhesion to SAA was comparable to fibronectin and lower than to fibrinogen. Adhesion to SAA was further enhanced by Mn(2+) and the physiological agonist, thrombin. Platelet adhesion to SAA was completely abolished by anti-SAA antibody. SAA-induced adhesion was inhibited by antibodies against the integrin receptor alphaIIbbeta3, by the peptide GRGDSP and by SAA-derived peptide containing YIGSR-like and RGD-like adhesion motifs (amino acids 29 to 42). Adhesion was not inhibited by control immunoglobulin G, by antibody against the integrin receptor alphaVbeta3, by the peptide GRGESP, and by SAA-derived peptide that includes incomplete RGD motif. SAA-derived peptide 29 to 42 also inhibited platelet adhesion to fibronectin. Transfected human melanoma cells expressing alphaIIbbeta3 adhered to SAA, whereas transfected cells expressing alphaVbeta3 did not. By using flow cytometry, the alphaIIbbeta3 cells displayed significantly higher levels of binding of soluble SAA than the alphaVbeta3 cells. These data indicate that human platelets specifically adhere to SAA in an RGD- and alphaIIbbeta3-dependent manner. Thus, SAA may play a role in modulating platelet adhesion at vascular injury sites by sharing platelet receptors with other platelet-adhesive proteins. PMID:11830469

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

    Rossmann, Christine; Windpassinger, Christian; Brunner, Daniela; Kovacevic, Alenka; Schweighofer, Natascha; Malli, Roland; Schuligoi, Rufina; Prokesch, Andreas; Kluve-Beckerman, Barbara; Wolfgang F Graier; Kratky, Dagmar; Sattler, Wolfgang; Malle, Ernst

    2014-01-01

    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...

  11. Amyloid β protein and Alzheimer disease

    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...

  12. Prediction of outcome in cancer patients with febrile neutropenia: comparison of the Multinational Association of Supportive Care in Cancer risk-index score with procalcitonin, C-reactive protein, serum amyloid A, and interleukins-1beta, -6, -8 and -10.

    Uys, A; Rapoport, B L; Fickl, H; Meyer, P W A; Anderson, R

    2007-11-01

    The primary objective of the study was to compare the predictive potential of procalcitonin (PCT), C-reactive protein (CRP), serum amyloid A (SAA), and interleukin (IL)-1beta, IL-6, IL-8, and IL-10, with that of the Multinational Association of Supportive Care in Cancer (MASCC) risk-index score in cancer patients on presentation with chemotherapy-induced febrile neutropenia (FN). Seventy-eight consecutive FN episodes in 63 patients were included, and MASCC scores, as well as concentrations of CRP, SAA, PCT, and IL-1beta, IL-6, IL-8 and IL-10, and haematological parameters were determined on presentation, 72 h later and at outcome. Multivariate analysis of data revealed the MASCC score, but none of the laboratory parameters, to be an accurate, independent variable (P < 0.0001) for prediction of resolution with or without complications and death. Of the various laboratory parameters, PCT had the strongest association with the MASCC score (r = -0.51; P < 0.0001). In cancer patients who present with FN, the MASCC risk-index score is a useful predictor of outcome, while measurement of PCT, CRP, SAA, or IL-1beta, IL-6, IL-8 and IL-10, is of limited value. PMID:17944761

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

    Busk, Peter; Jacobsen, Stine; Martinussen, Torben

    2010-01-01

    Objectives: To compare postoperative inflammatory responses in horses administered perioperative procaine penicillin and those not administered penicillin using acute phase protein serum amyloid A (SAA) as a marker of inflammation. Study Design: Randomized clinical trial. Animals: Stallions (n = 50...... administered NSAID and 25,000 U/kg procaine penicillin on day 0, 1, and 2. Results: SAA concentrations increased significantly from preoperative levels in both groups, and on day 8 concentrations were significantly (P o .02) higher in horses administered only NSAID than in those administered procaine penicillin...

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

    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...... expression pattern of SAA significantly correlated to the immunohistochemical analysis of the infected fry. A weak staining was seen in liver tissue at 4 h post infection which increased in intensity during the course of infection i.e. 24, 72 and 96 h post infection....

  15. Impact of serum amyloid A on high density lipoprotein composition and levels

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

    2010-01-01

    Serum amyloid A (SAA) is an acute-phase protein mainly associated with HDL. To study the role of SAA in mediating changes in HDL composition and metabolism during inflammation, we generated mice in which the two major acute-phase SAA isoforms, SAA1.1 and SAA2.1, were deleted [SAA knockout (SAAKO) mice], and induced an acute phase to compare lipid and apolipoprotein parameters between wild-type (WT) and SAAKO mice. Our data indicate that SAA does not affect apolipoprotein A-I (apoA-I) levels o...

  16. Amyloid β-sheet mimics that antagonize protein aggregation and reduce amyloid toxicity

    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 β-sheet-rich structures in transition from native proteins to ordered oligomers and fibres. The variation in the amino-acid sequences of the β-structures presents a challenge to developing a model system of β-sheets for the study of various amyloid aggregates. Here, we introduce a family of robust β-sheet macrocycles that can serve as a platform to display a variety of heptapeptide sequences from different amyloid proteins. We have tailored these amyloid β-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-β peptide associated with Alzheimer's disease, β2-microglobulin associated with dialysis-related amyloidosis, α-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.

  17. A Novel Truncated Form of Serum Amyloid A in Kawasaki Disease.

    John C Whitin

    Full Text Available Kawasaki disease (KD is an acute vasculitis in children that can cause coronary artery abnormalities. Its diagnosis is challenging, and many cytokines, chemokines, acute phase reactants, and growth factors have failed evaluation as specific biomarkers to distinguish KD from other febrile illnesses. We performed protein profiling, comparing plasma from children with KD with febrile control (FC subjects to determine if there were specific proteins or peptides that could distinguish the two clinical states.Plasma from three independent cohorts from the blood of 68 KD and 61 FC subjects was fractionated by anion exchange chromatography, followed by surface-enhanced laser desorption ionization (SELDI mass spectrometry of the fractions. The mass spectra of KD and FC plasma samples were analyzed for peaks that were statistically significantly different.A mass spectrometry peak with a mass of 7,860 Da had high intensity in acute KD subjects compared to subacute KD (p = 0.0003 and FC (p = 7.9 x 10-10 subjects. We identified this peak as a novel truncated form of serum amyloid A with N-terminal at Lys-34 of the circulating form and validated its identity using a hybrid mass spectrum immunoassay technique. The truncated form of serum amyloid A was present in plasma of KD subjects when blood was collected in tubes containing protease inhibitors. This peak disappeared when the patients were examined after their symptoms resolved. Intensities of this peptide did not correlate with KD-associated laboratory values or with other mass spectrum peaks from the plasma of these KD subjects.Using SELDI mass spectrometry, we have discovered a novel truncated form of serum amyloid A that is elevated in the plasma of KD when compared with FC subjects. Future studies will evaluate its relevance as a diagnostic biomarker and its potential role in the pathophysiology of KD.

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

    Jacobsen, Stine; Niewold, T.A.; Kornalijnslijper, 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.......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....

  19. Serum amyloid P therapeutically attenuates murine bleomycin-induced pulmonary fibrosis via its effects on macrophages.

    Lynne A Murray

    Full Text Available Macrophages promote tissue remodeling but few mechanisms exist to modulate their activity during tissue fibrosis. Serum amyloid P (SAP, a member of the pentraxin family of proteins, signals through Fcgamma receptors which are known to affect macrophage activation. We determined that IPF/UIP patients have increased protein levels of several alternatively activated pro-fibrotic (M2 macrophage-associated proteins in the lung and monocytes from these patients show skewing towards an M2 macrophage phenotype. SAP therapeutically inhibits established bleomycin-induced pulmonary fibrosis, when administered systemically or locally to the lungs. The reduction in aberrant collagen deposition was associated with a reduction in M2 macrophages in the lung and increased IP10/CXCL10. These data highlight the role of macrophages in fibrotic lung disease, and demonstrate a therapeutic action of SAP on macrophages which may extend to many fibrotic indications caused by over-exuberant pro-fibrotic macrophage responses.

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

    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.

  1. SERF Protein Is a Direct Modifier of Amyloid Fiber Assembly

    S. Fabio Falsone

    2012-08-01

    Full Text Available The inherent cytotoxicity of aberrantly folded protein aggregates contributes substantially to the pathogenesis of amyloid diseases. It was recently shown that a class of evolutionary conserved proteins, called MOAG-4/SERF, profoundly alter amyloid toxicity via an autonomous but yet unexplained mode. We show that the biological function of human SERF1a originates from its atypical ability to specifically distinguish between amyloid and nonamyloid aggregation. This inherently unstructured protein directly affected the aggregation kinetics of a broad range of amyloidogenic proteins in vitro, while being inactive against nonamyloid aggregation. A representative biophysical analysis of the SERF1a:α-synuclein (aSyn complex revealed that the amyloid-promoting activity resulted from an early and transient interaction, which was sufficient to provoke a massive increase of soluble aSyn amyloid nucleation templates. Therefore, the autonomous amyloid-modifying activity of SERF1a observed in living organisms relies on a direct and dedicated manipulation of the early stages in the amyloid aggregation pathway.

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

    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...

  3. Generation of amyloid-β is reduced by the interaction of calreticulin with amyloid precursor protein, presenilin and nicastrin.

    Nina Stemmer

    Full Text Available Dysregulation of the proteolytic processing of amyloid precursor protein by γ-secretase and the ensuing generation of amyloid-β is associated with the pathogenesis of Alzheimer's disease. Thus, the identification of amyloid precursor protein binding proteins involved in regulating processing of amyloid precursor protein by the γ-secretase complex is essential for understanding the mechanisms underlying the molecular pathology of the disease. We identified calreticulin as novel amyloid precursor protein interaction partner that binds to the γ-secretase cleavage site within amyloid precursor protein and showed that this Ca(2+- and N-glycan-independent interaction is mediated by amino acids 330-344 in the C-terminal C-domain of calreticulin. Co-immunoprecipitation confirmed that calreticulin is not only associated with amyloid precursor protein but also with the γ-secretase complex members presenilin and nicastrin. Calreticulin was detected at the cell surface by surface biotinylation of cells overexpressing amyloid precursor protein and was co-localized by immunostaining with amyloid precursor protein and presenilin at the cell surface of hippocampal neurons. The P-domain of calreticulin located between the N-terminal N-domain and the C-domain interacts with presenilin, the catalytic subunit of the γ-secretase complex. The P- and C-domains also interact with nicastrin, another functionally important subunit of this complex. Transfection of amyloid precursor protein overexpressing cells with full-length calreticulin leads to a decrease in amyloid-β42 levels in culture supernatants, while transfection with the P-domain increases amyloid-β40 levels. Similarly, application of the recombinant P- or C-domains and of a synthetic calreticulin peptide comprising amino acid 330-344 to amyloid precursor protein overexpressing cells result in elevated amyloid-β40 and amyloid-β42 levels, respectively. These findings indicate that the interaction of

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

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

    2013-01-01

    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...... 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...

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

    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 (μg/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 (μg/ml and Hp (μg/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.

  6. Amyloid-beta Alzheimer targets - protein processing, lipid rafts, and amyloid-beta pores.

    Arbor, Sage C; LaFontaine, Mike; Cumbay, Medhane

    2016-03-01

    Amyloid beta (Aβ), the hallmark of Alzheimer's Disease (AD), now appears to be deleterious in its low number aggregate form as opposed to the macroscopic Aβ fibers historically seen postmortem. While Alzheimer targets, such as the tau protein, amyloid precursor protein (APP) processing, and immune system activation continue to be investigated, the recent discovery that amyloid beta aggregates at lipid rafts and likely forms neurotoxic pores has led to a new paradigm regarding why past therapeutics may have failed and how to design the next round of compounds for clinical trials. An atomic resolution understanding of Aβ aggregates, which appear to exist in multiple conformations, is most desirable for future therapeutic development. The investigative difficulties, structures of these small Aβ aggregates, and current therapeutics are summarized in this review. PMID:27505013

  7. Amyloid-beta Alzheimer targets — protein processing, lipid rafts, and amyloid-beta pores

    Arbor, Sage C.; LaFontaine, Mike; Cumbay, Medhane

    2016-01-01

    Amyloid beta (Aβ), the hallmark of Alzheimer’s Disease (AD), now appears to be deleterious in its low number aggregate form as opposed to the macroscopic Aβ fibers historically seen postmortem. While Alzheimer targets, such as the tau protein, amyloid precursor protein (APP) processing, and immune system activation continue to be investigated, the recent discovery that amyloid beta aggregates at lipid rafts and likely forms neurotoxic pores has led to a new paradigm regarding why past therapeutics may have failed and how to design the next round of compounds for clinical trials. An atomic resolution understanding of Aβ aggregates, which appear to exist in multiple conformations, is most desirable for future therapeutic development. The investigative difficulties, structures of these small Aβ aggregates, and current therapeutics are summarized in this review.

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

    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

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

    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

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

    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.

  11. Expression of apolipoprotein serum amyloid A mRNA in human atherosclerotic lesions and cultured vascular cells: implications for serum amyloid A function.

    Meek, R L; Urieli-Shoval, S.; Benditt, E. P.

    1994-01-01

    Altered lipoprotein metabolism and vascular injury are considered to be major parts of the pathogenesis of atherosclerotic lesions. Serum amyloid A (SAA) is a family of acute-phase reactants found residing mainly on high density lipoproteins (HDL) in the circulation. Several functions for the SAAs have been proposed that could be important in atherosclerosis. These include involvement in cholesterol metabolism, participation in detoxification, depression of immune responses, and interference ...

  12. Formation of Toxic Amyloid Fibrils by Amyloid β-Protein on Ganglioside Clusters

    Katsumi Matsuzaki

    2011-01-01

    Full Text Available It is widely accepted that the conversion of the soluble, nontoxic amyloid β-protein (Aβ monomer to aggregated toxic Aβ rich in β-sheet structures is central to the development of Alzheimer’s disease. However, the mechanism of the abnormal aggregation of Aβ in vivo is not well understood. Accumulating evidence suggests that lipid rafts (microdomains in membranes mainly composed of sphingolipids (gangliosides and sphingomyelin and cholesterol play a pivotal role in this process. This paper summarizes the molecular mechanisms by which Aβ aggregates on membranes containing ganglioside clusters, forming amyloid fibrils. Notably, the toxicity and physicochemical properties of the fibrils are different from those of Aβ amyloids formed in solution. Furthermore, differences between Aβ-(1–40 and Aβ-(1–42 in membrane interaction and amyloidogenesis are also emphasized.

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

    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

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

    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

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

    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.

  16. 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

    Heegaard, Peter M. H.; Klausen, Joan; Nielsen, J.P.;

    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 ...

  17. Serum- and HDL3-serum amyloid A and HDL3-LCAT activity are influenced by increased CVD-burden

    McEneny, Jane; McKavanagh, Peter; York, Edmund; Nadeem, Nida; Harbinson, Mark; Stevenson, Michael; Ball, Peter; Lusk, Lisa; Trinick, Thomas; Young, Ian S; McKay, Gareth J; Donnelly, Patrick M.

    2016-01-01

    BACKGROUND: High density lipoproteins (HDL) protect against cardiovascular disease (CVD). However, increased serum amyloid-A (SAA) related inflammation may negate this property. This study investigated if SAA was related to CVD-burden.METHODS: Subjects referred to the rapid chest pain clinic (n = 240) had atherosclerotic burden assessed by cardiac computerised tomography angiography. Subjects were classified as: no-CVD (n = 106), non-obstructive-CVD, stenosis<50% (n = 58) or moderate/signi...

  18. Cerebroprotective effect of Huanglian Jiedu decoction on amyloid protein precursor/presenilin-1 double transgenic mice

    Xin Qiu; Guohua Chen; Gui Mei; Yuegu Wang; Kaixin Wang; Tao Wang; Pei Feng

    2011-01-01

    Huanglian Jiedu decoction (HLJDD) has been shown to improve cerebral blood flow, and reduce lipid peroxidation damage to the brain and its energy metabolism. The present study was designed to observe the cerebroprotective effect of HLJDD on an Alzheimer's disease rodent model,presenilin-1/amyloid protein precursor double transgenic mice. HLJDD reduced serum interleukin-6 and interleukin-1β levels, decreased β-amyloid precursor protein gene and senile plaque expression, resisted oxidation, and reduced free radical-induced injury, thereby improving the learning and memory of these mice. Moreover, HLJDD at 433 mg/kg per day exhibited better effects compared with that at 865 or 216 mg/kg per day, and donepezil hydrochloride at 30 mg/kg per day.Thus, these results suggest that HLJDD may have protective effects against Alzheimer's disease.

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

    Kjelgaard-Hansen, Mads Jens; Christensen, Michelle B.; Lee, Marcel Huisung;

    2007-01-01

    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 denaturing isoelectric focusing and Western blotting. Serum amyloid A was present in serum from all dogs...... with systemic inflammatory activity, and up to four major isoforms with apparent isoelectric points between 6.1 and 7.9 were identified. In synovial fluid from inflamed joints one or more highly alkaline SAA isoforms (with apparent isoelectric points above 9.3) were identified, with data suggesting local...... production of these isoforms in the canine inflamed joint....

  20. Interaction of amyloid inhibitor proteins with amyloid beta peptides: insight from molecular dynamics simulations.

    Payel Das

    Full Text Available Knowledge of the detailed mechanism by which proteins such as human αB- crystallin and human lysozyme inhibit amyloid beta (Aβ peptide aggregation is crucial for designing treatment for Alzheimer's disease. Thus, unconstrained, atomistic molecular dynamics simulations in explicit solvent have been performed to characterize the Aβ17-42 assembly in presence of the αB-crystallin core domain and of lysozyme. Simulations reveal that both inhibitor proteins compete with inter-peptide interaction by binding to the peptides during the early stage of aggregation, which is consistent with their inhibitory action reported in experiments. However, the Aβ binding dynamics appear different for each inhibitor. The binding between crystallin and the peptide monomer, dominated by electrostatics, is relatively weak and transient due to the heterogeneous amino acid distribution of the inhibitor surface. The crystallin-bound Aβ oligomers are relatively long-lived, as they form more extensive contact surface with the inhibitor protein. In contrast, a high local density of arginines from lysozyme allows strong binding with Aβ peptide monomers, resulting in stable complexes. Our findings not only illustrate, in atomic detail, how the amyloid inhibitory mechanism of human αB-crystallin, a natural chaperone, is different from that of human lysozyme, but also may aid de novo design of amyloid inhibitors.

  1. Amyloid Precursor Protein Processing in Alzheimer’s Disease

    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 (Aβ, 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 Aβ 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

  2. Unusual cerebral vascular prion protein amyloid distribution in scrapie-infected transgenic mice expressing anchorless prion protein

    Rangel, Alejandra; Race, Brent; Klingeborn, Mikael; Striebel, James; Chesebro, Bruce

    2013-01-01

    Background In some prion diseases, misfolded aggregated protease-resistant prion protein (PrPres) is found in brain as amyloid, which can cause cerebral amyloid angiopathy. Small diffusible precursors of PrPres amyloid might flow with brain interstitial fluid (ISF), possibly accounting for the perivascular and intravascular distribution of PrPres amyloid. We previously reported that PrPres amyloid in scrapie-infected transgenic mice appeared to delay clearance of microinjected brain ISF trace...

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

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

    2013-01-01

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

  4. Adaptor protein sorting nexin 17 regulates amyloid precursor protein trafficking and processing in the early endosomes

    Lee, Jiyeon; Retamal, Claudio; Cuitino, Loreto; Caruano-Yzermans, Amy; Shin, Jung-Eun; van Kerkhof, Peter; Marzolo, Maria-Paz; Bu, Guojun

    2008-01-01

    Accumulation of extracellular amyloid beta peptide (A beta), generated from amyloid precursor protein (APP) processing by beta- and gamma-secretases, is toxic to neurons and is central to the pathogenesis of Alzheimer disease. Production of A beta from APP is greatly affected by the subcellular loca

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

    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

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

    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.

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

    Olsen, Helle G; Skovgaard, Kerstin; Nielsen, Ole L;

    2013-01-01

    Serum amyloid A (SAA) is a prominent acute phase protein. Although its biological functions are debated, the wide species distribution of highly homologous SAA proteins and their uniform behavior in response to injury or inflammation in itself suggests a significant role for this protein. The pig...... is increasingly being used as a model for the study of inflammatory reactions, yet only little is known about how specific SAA genes are regulated in the pig during acute phase responses and other responses induced by pro-inflammatory host mediators. We designed SAA gene specific primers and...... quantified the gene expression of porcine SAA1, SAA2, SAA3, and SAA4 by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) in liver, spleen, and lung tissue from pigs experimentally infected with the Gram-negative swine specific bacterium Actinobacillus pleuropneumoniae, as well as from...

  8. Divalent cation tolerance protein binds to β-secretase and inhibits the processing of amyloid precursor protein

    Runzhong Liu; Haibo Hou; Xuelian Yi; Shanwen Wu; Huan Zeng

    2013-01-01

    The deposition of amyloid-beta is a pathological hallmark of Alzheimer's disease. Amyloid-beta is derived from amyloid precursor protein through sequential proteolytic cleavages by β-secretase (beta-site amyloid precursor protein-cleaving enzyme 1) and γ-secretase. To further elucidate the roles of beta-site amyloid precursor protein-cleaving enzyme 1 in the development of Alzheimer's disease, a yeast two-hybrid system was used to screen a human embryonic brain cDNA library for proteins directly interacting with the intracellular domain of beta-site amyloid precursor protein-cleaving enzyme 1. A potential beta-site amyloid precursor protein-cleaving enzyme 1- interacting protein identified from the positive clones was divalent cation tolerance protein. Immunoprecipitation studies in the neuroblastoma cell line N2a showed that exogenous divalent cation tolerance protein interacts with endogenous beta-site amyloid precursor protein-cleaving enzyme 1. The overexpression of divalent cation tolerance protein did not affect beta-site amyloid precursor protein-cleaving enzyme 1 protein levels, but led to increased amyloid precursor protein levels in N2a/APP695 cells, with a concomitant reduction in the processing product amyloid precursor protein C-terminal fragment, indicating that divalent cation tolerance protein inhibits the processing of amyloid precursor protein. Our experimental findings suggest that divalent cation tolerance protein negatively regulates the function of beta-site amyloid precursor protein-cleaving enzyme 1. Thus, divalent cation tolerance protein could play a protective role in Alzheimer's disease.

  9. MetAmyl: a METa-predictor for AMYLoid proteins.

    Mathieu Emily

    Full Text Available The aggregation of proteins or peptides in amyloid fibrils is associated with a number of clinical disorders, including Alzheimer's, Huntington's and prion diseases, medullary thyroid cancer, renal and cardiac amyloidosis. Despite extensive studies, the molecular mechanisms underlying the initiation of fibril formation remain largely unknown. Several lines of evidence revealed that short amino-acid segments (hot spots, located in amyloid precursor proteins act as seeds for fibril elongation. Therefore, hot spots are potential targets for diagnostic/therapeutic applications, and a current challenge in bioinformatics is the development of methods to accurately predict hot spots from protein sequences. In this paper, we combined existing methods into a meta-predictor for hot spots prediction, called MetAmyl for METapredictor for AMYLoid proteins. MetAmyl is based on a logistic regression model that aims at weighting predictions from a set of popular algorithms, statistically selected as being the most informative and complementary predictors. We evaluated the performances of MetAmyl through a large scale comparative study based on three independent datasets and thus demonstrated its ability to differentiate between amyloidogenic and non-amyloidogenic polypeptides. Compared to 9 other methods, MetAmyl provides significant improvement in prediction on studied datasets. We further show that MetAmyl is efficient to highlight the effect of point mutations involved in human amyloidosis, so we suggest this program should be a useful complementary tool for the diagnosis of these diseases.

  10. Scintigraphic imaging and turnover studies with iodine-131 labelled serum amyloid P component in systemic amyloidosis

    Radiolabelled serum amyloid P component (SAP) is a specific tracer for amyloid. Iodine-123 has ideal physical characteristics for scintigraphy but is expensive and not widely available. Here we report serial imaging and turnover studies in which we labelled SAP with iodine-131, a cheap alternative isotope which would be expected to yield poorer images but permit more prolonged turnover measurements. Imaging and plasma clearance and whole body retention (WBR) of tracer were studied for up to 7 days in ten patients with proven systemic AL amyloidosis and two patients in whom the diagnosis was suspected, after i.v. administration of about 37 MBq of 131I-SAP. Normal blood pool images were obtained in the latter two subjects and amyloidosis was subsequently refuted histologically. WBR at 48 h was 65% of the injected dose (i.d.). Among the other ten patients, amyloid deposits were identified in the spleen in eight cases, liver in five and kidneys in four; other sites that gave positive results included bone, joints and soft tissues, and the myocardium in one case. Up to 95% of the tracer localised into amyloid within 6-h, and the values for WBR became progressively more discriminating during the study period, exceeding the normal reference value (131I-SAP produced diagnostic scans in every patient in this series and, coupled with the detailed turnover information, is adequate for monitoring disease progress. (orig.)

  11. Amyloid fibril protein nomenclature: 2012 recommendations from the Nomenclature Committee of the International Society of Amyloidosis.

    Sipe, Jean D; Benson, Merrill D; Buxbaum, Joel N; Ikeda, Shu-ichi; Merlini, Giampaolo; Saraiva, Maria J M; Westermark, Per

    2012-12-01

    The Nomenclature Committee of the International Society of Amyloidosis (ISA) met during the XIIIth International Symposium, May 6-10, 2012, Groningen, The Netherlands, to formulate recommendations on amyloid fibril protein nomenclature and to consider newly identified candidate amyloid fibril proteins for inclusion in the ISA Amyloid Fibril Protein Nomenclature List. The need to promote utilization of consistent and up to date terminology for both fibril chemistry and clinical classification of the resultant disease syndrome was emphasized. Amyloid fibril nomenclature is based on the chemical identity of the amyloid fibril forming protein; clinical classification of the amyloidosis should be as well. Although the importance of fibril chemistry to the disease process has been recognized for more than 40 years, to this day the literature contains clinical and histochemical designations that were used when the chemical diversity of amyloid diseases was poorly understood. Thus, the continued use of disease classifications such as familial amyloid neuropathy and familial amyloid cardiomyopathy generates confusion. An amyloid fibril protein is defined as follows: the protein must occur in body tissue deposits and exhibit both affinity for Congo red and green birefringence when Congo red stained deposits are viewed by polarization microscopy. Furthermore, the chemical identity of the protein must have been unambiguously characterized by protein sequence analysis when so is practically possible. Thus, in nearly all cases, it is insufficient to demonstrate mutation in the gene of a candidate amyloid protein; the protein itself must be identified as an amyloid fibril protein. Current ISA Amyloid Fibril Protein Nomenclature Lists of 30 human and 10 animal fibril proteins are provided together with a list of inclusion bodies that, although intracellular, exhibit some or all of the properties of the mainly extracellular amyloid fibrils. PMID:23113696

  12. Evaluation of serum amyloid A and haptoglobin concentrations as prognostic indicators for horses with colic.

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

    2016-04-15

    OBJECTIVE To evaluate the use of the acute-phase proteins serum amyloid A (SAA) and haptoglobin as prognostic indicators in horses with colic with regard to the need for surgical intervention, development of complications, and hospitalization cost and duration. DESIGN Prospective observational study. ANIMALS 20 clinically normal horses and 42 horses with colic. PROCEDURES Total WBC and neutrophil counts and plasma fibrinogen, SAA, and haptoglobin concentrations were compared between healthy (control) horses and horses admitted to a veterinary teaching hospital for colic. Clinicopathologic values were compared between medical and surgical colic cases to test the ability of acute-phase proteins to predict indication for surgical intervention, development of complications, and duration and cost of hospitalization. RESULTS Mean SAA concentration was significantly higher in the surgical group, compared with that for both the control and medical groups. Haptoglobin concentration did not differ significantly among groups. Horses with colic and an abnormally increased SAA concentration (> 5 μg/mL) were more likely to be managed surgically than medically (OR, 5.7; 95% confidence interval, 1.4 to 22.8). Horses with small intestinal lesions had significantly higher SAA concentrations than did control horses. Euthanasia due to a poor prognosis or the development of thrombophlebitis was more likely for horses with an SAA concentration > 5 μg/mL (OR, 7.6; 95% confidence interval, 1.1 to 52.4). A weak positive correlation (r = 0.30) was observed between cost of treatment and SAA concentration. CONCLUSIONS AND CLINICAL RELEVANCE Horses with colic that had an abnormally increased SAA concentration were more likely to require surgical intervention, develop thrombophlebitis, or be euthanized because of a poor prognosis despite treatment. PMID:27031421

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

    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-1α/β and TNFα 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.

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

    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-1α/β and TNFα 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

  15. The proteome response to amyloid protein expression in vivo.

    Ricardo A Gomes

    Full Text Available Protein misfolding disorders such as Alzheimer, Parkinson and transthyretin amyloidosis are characterized by the formation of protein amyloid deposits. Although the nature and location of the aggregated proteins varies between different diseases, they all share similar molecular pathways of protein unfolding, aggregation and amyloid deposition. Most effects of these proteins are likely to occur at the proteome level, a virtually unexplored reality. To investigate the effects of an amyloid protein expression on the cellular proteome, we created a yeast expression system using human transthyretin (TTR as a model amyloidogenic protein. We used Saccharomyces cerevisiae, a living test tube, to express native TTR (non-amyloidogenic and the amyloidogenic TTR variant L55P, the later forming aggregates when expressed in yeast. Differential proteome changes were quantitatively analyzed by 2D-differential in gel electrophoresis (2D-DIGE. We show that the expression of the amyloidogenic TTR-L55P causes a metabolic shift towards energy production, increased superoxide dismutase expression as well as of several molecular chaperones involved in protein refolding. Among these chaperones, members of the HSP70 family and the peptidyl-prolyl-cis-trans isomerase (PPIase were identified. The latter is highly relevant considering that it was previously found to be a TTR interacting partner in the plasma of ATTR patients but not in healthy or asymptomatic subjects. The small ubiquitin-like modifier (SUMO expression is also increased. Our findings suggest that refolding and degradation pathways are activated, causing an increased demand of energetic resources, thus the metabolic shift. Additionally, oxidative stress appears to be a consequence of the amyloidogenic process, posing an enhanced threat to cell survival.

  16. Serum amyloid A in the placenta and its role in trophoblast invasion.

    Silvana Sandri

    Full Text Available The serum amyloid A (SAA protein is known to function in the acute phase response and immunoregulation. Recently, SAA has been shown to be involved in cell proliferation, differentiation and migratory behavior in different cell types. Here, we evaluated whether exogenous SAA could influence trophoblast invasion and differentiation using both the trophoblast-like BeWo cell line and fully differentiated human extravillous trophoblast cells (EVT isolated from term placentae. SAA stimulated BeWo cell invasion, as measured in Matrigel invasion assays, and induced metalloprotease mRNA expression and activity. Given that BeWo cells express Toll-like receptor 4 (TLR4, a known receptor for SAA, we examined the role of TLR4 in SAA-induced invasion using a TLR4 neutralizing antibody. We also tested whether SAA could affect markers of trophoblast syncytialization in BeWo cells. We observed that SAA decreased βhCG secretion and did not influence trophoblast syncytialization. Using EVT cells isolated from human term basal plates, we confirmed that SAA at 1 and 10 µg/mL doubled EVT invasion in a TLR4-dependent manner, but at 20 µg/mL inhibited EVT cells invasiveness. In addition, we observed that SAA was expressed in both BeWo cells and human term placentae, specifically in the syncytiotrophoblast, decidual cells and EVT. In conclusion, SAA was identified as a molecule that functions in the placental microenvironment to regulate metalloprotease activity and trophoblast invasion, which are key processes in placentation and placental homeostasis.

  17. Expression of serum amyloid a in equine wounds

    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......, which is produced in the liver and several extrahepatic tissues during inflammatory conditions. This study shows that cells in EGT derived from horses produce SAA. This may be related to the length of the inflammatory phase of the wound healing, which is short (approximately 3 days) in wounds with...

  18. Expression and processing of fluorescent fusion proteins of amyloid precursor protein (APP)☆

    Coughlan, Kathleen; Huang, Xiangping; He, Xiangyuan; Chung, Charlotte H.Y.; Li, Guangpu; Tang, Jordan

    2013-01-01

    Processing of β-amyloid precursor protein (APP) by β- and γ-secretases in neurons produces amyloid-β (Aβ), whose excess accumulation leads to Alzheimer’s disease (AD). Knowledge on subcellular trafficking pathways of APP and its fragments is important for the understanding of AD pathogenesis. We designed fusion proteins comprising a C-terminal fragment of APP (app) and fluorescent proteins GFP (G) and DsRed (D) to permit the tracking of the fusion proteins and fragments in cells. CAD cells ex...

  19. The effects of chondroitin sulfate and serum albumin on the fibrillation of human islet amyloid polypeptide at phospholipid membranes.

    Li, Yang; Wang, Li; Lu, Tong; Wei, Ying; Li, Fei

    2016-04-28

    Glycosaminoglycans and serum albumin are important cellular components that regulate the fibril formation of proteins. Whereas the effects of cellular components on the fibrillation of amyloid proteins in bulk solution are widely studied, less attention has been paid to the effects of cellular components on amyloidogenesis occurring at cellular membranes. In this study, we focus on the impacts of chondroitin sulfate A (CSA) and bovine serum albumin (BSA) on the amyloidogenic behaviors of human islet amyloid polypeptide (hIAPP) at phospholipid membranes consisting of neutral POPC and anionic POPG. Using the thioflavin T fluorescence assay, atomic force microscopy, circular dichroism and nuclear magnetic resonance measurements, we demonstrate that CSA has an intensive promotion effect on the fibrillation of hIAPP at the POPC membrane, which is larger than the total effect of CSA alone and POPC alone. The further enhanced promotion of the fibrillation of hIAPP by CSA at the neutral membrane is associated with a specific interaction of CSA with POPC. In contrast, the activity of BSA as an inhibitor of hIAPP fibrillation observed in bulk solution decreases dramatically in the presence of POPG vesicles. The dramatic loss of the inhibition efficiency of BSA arises essentially from a specific interaction with the POPG component, but not simply from suppression by an opposite effect of the anionic membrane. The findings in this study suggest that the interactions between membranes and cellular components may have a significant effect on the activity of the cellular components in regulating the fibrillation of hIAPP. PMID:27067251

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

    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-1β, interleukin 6 (IL-6, tumor necrosis factor-α (TNF-α 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-1β, IL-6 and TNF-α 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

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

    Nilsson, Tatjana; Malkiewicz, Katarzyna; Gabrielsson, Maria;

    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...... signalling events. This study shows that antibody-bound APP leads to altered gene expression that may be relevant to AD....... 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...

  2. Effect of ascorbic acid and alpha-tocopherol supplementations on serum leptin, tumor necrosis factor alpha, and serum amyloid A levels in individuals with type 2 diabetes mellitus

    Mostafa Jamalan

    2015-10-01

    Full Text Available Objective: Diabetes mellitus Type 2 is one of the most widespread chronic metabolic diseases. In most cases, this type of diabetes is associated with alterations in levels of some inflammatory cytokines and hormones. Considering anti-inflammatory properties of plant extracts rich in ascorbic acid (vitamin C and alpha-tocopherol (vitamin E, anti-diabetic properties of these two well-known antioxidant vitamins were investigated through measurement of serum levels of high-sensitivity C-reactive protein (hs-CRP, insulin, leptin, tumor necrosis factor alpha (TNF-α, and serum amyloid A (SAA in patients with diabetes mellitus type 2. Methods: Male patients (n=80 were randomly divided into two groups each consisted of 40 subjects. Test groups were supplemented with ascorbic acid (1000 mg/day or alpha-tocopherol (300 mg/day orally during four weeks. Before and after treatment, serum biochemical factors of subjects were measured and compared. Results: Our results showed that both ascorbic acid and alpha-tocopherol could induce significant anti-inflammatory effects by decreasing the level of inflammatory factors such as TNF-α, SAA, and hs-CRP in diabetes mellitus type 2 patients. Effects of alpha-tocopherol and ascorbic acid in decreasing serum leptin level were similar. Ascorbic acid in contrast to alpha-tocopherol diminished fasting insulin and HOMA index but had no effect on LDL serum level. Conclusion: Concerning the obtained results, it is concluded that consumption of supplementary vitamins C and E could decrease induced inflammatory response in patients with diabetes mellitus type 2.  It is also possible that vitamin C and vitamin E supplementation can attenuate incidence of some proposed pathological effects of diabetes mellitus.

  3. Structure and Expression of Different Serum Amyloid A (SAA) Variants and their Concentration-Dependent Functions During Host Insults.

    De Buck, Mieke; Gouwy, Mieke; Wang, Ji Ming; Van Snick, Jacques; Opdenakker, Ghislain; Struyf, Sofie; Van Damme, Jo

    2016-01-01

    Serum amyloid A (SAA) is, like C-reactive protein (CRP), an acute phase protein and can be used as a diagnostic, prognostic or therapy follow-up marker for many diseases. Increases in serum levels of SAA are triggered by physical insults to the host, including infection, trauma, inflammatory reactions and cancer. The order of magnitude of increase in SAA levels varies considerably, from a 10- to 100- fold during limited inflammatory events to a 1000-fold increase during severe bacterial infections and acute exacerbations of chronic inflammatory diseases. This broad response range is reflected by SAA gene duplications resulting in a cluster encoding several SAA variants and by multiple biological functions of SAA. SAA variants are single-domain proteins with simple structures and few post-translational modifications. SAA1 and SAA2 are inducible by inflammatory cytokines, whereas SAA4 is constitutively produced. We review here the regulated expression of SAA in normal and transformed cells and compare its serum levels in various disease states. At low concentrations (10-100 ng/ml), early in an inflammatory response, SAA induces chemokines or matrix degrading enzymes via Toll-like receptors and functions as an activator and chemoattractant through a G protein-coupled receptor. When an infectious or inflammatory stimulus persists, the liver continues to produce more SAA (≥ 1000 ng/ml) to become an antimicrobial agent by functioning as a direct opsonin of bacteria or by interference with virus infection of host cells. Thus, SAA regulates innate and adaptive immunity and this information may help to design better drugs to treat specific diseases. PMID:27087246

  4. The amyloid precursor protein and postnatal neurogenesis/neuroregeneration

    The amyloid precursor protein (APP) is the source of amyloid-beta (Aβ) peptide, produced via its sequential cleavage β- and γ-secretases. Various biophysical forms of Aβ (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 Aβ sequence, however, suggest that these might have important physiological functions that are unrelated to Aβ 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

  5. Small heat shock proteins potentiate amyloid dissolution by protein disaggregases from yeast and humans.

    Martin L Duennwald

    Full Text Available How small heat shock proteins (sHsps might empower proteostasis networks to control beneficial prions or disassemble pathological amyloid is unknown. Here, we establish that yeast sHsps, Hsp26 and Hsp42, inhibit prionogenesis by the [PSI+] prion protein, Sup35, via distinct and synergistic mechanisms. Hsp42 prevents conformational rearrangements within molten oligomers that enable de novo prionogenesis and collaborates with Hsp70 to attenuate self-templating. By contrast, Hsp26 inhibits self-templating upon binding assembled prions. sHsp binding destabilizes Sup35 prions and promotes their disaggregation by Hsp104, Hsp70, and Hsp40. In yeast, Hsp26 or Hsp42 overexpression prevents [PSI+] induction, cures [PSI+], and potentiates [PSI+]-curing by Hsp104 overexpression. In vitro, sHsps enhance Hsp104-catalyzed disaggregation of pathological amyloid forms of α-synuclein and polyglutamine. Unexpectedly, in the absence of Hsp104, sHsps promote an unprecedented, gradual depolymerization of Sup35 prions by Hsp110, Hsp70, and Hsp40. This unanticipated amyloid-depolymerase activity is conserved from yeast to humans, which lack Hsp104 orthologues. A human sHsp, HspB5, stimulates depolymerization of α-synuclein amyloid by human Hsp110, Hsp70, and Hsp40. Thus, we elucidate a heretofore-unrecognized human amyloid-depolymerase system that could have applications in various neurodegenerative disorders.

  6. Serum Protein Profile Alterations in Hemodialysis Patients

    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.

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

    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 α-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

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

    Ma, Ying Jie; Doni, Andrea; Skjoedt, Mikkel-Ole;

    2011-01-01

    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......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...

  9. Two adjacent C/EBP-binding sequences that participate in the cell-specific expression of the mouse serum amyloid A3 gene.

    Li, X. X.; J.H. Huang; Rienhoff, H Y; Liao, W S

    1990-01-01

    Serum amyloid A (SAA) is a major acute-phase protein synthesized primarily in the liver. Its expression, very low in normal animals, is increased several hundredfold following acute inflammation. To examine DNA sequences involved in liver-specific expression, 5'-flanking regions of the mouse SAA3 gene were analyzed by transient transfection, band shift, and DNase I protection assays. We found that a 56-bp fragment immediately 5' to the TATA box spanning the region -93 to -38 relative to the t...

  10. Amyloid precursor protein is trafficked and secreted via synaptic vesicles.

    Teja W Groemer

    Full Text Available A large body of evidence has implicated amyloid precursor protein (APP and its proteolytic derivatives as key players in the physiological context of neuronal synaptogenesis and synapse maintenance, as well as in the pathology of Alzheimer's Disease (AD. Although APP processing and release are known to occur in response to neuronal stimulation, the exact mechanism by which APP reaches the neuronal surface is unclear. We now demonstrate that a small but relevant number of synaptic vesicles contain APP, which can be released during neuronal activity, and most likely represent the major exocytic pathway of APP. This novel finding leads us to propose a revised model of presynaptic APP trafficking that reconciles existing knowledge on APP with our present understanding of vesicular release and recycling.

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

    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...

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

    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, IL1β, 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.

  13. 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

    S. Martínez-Subiela

    2005-01-01

    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 (SAA 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 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 amyloid 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

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

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

  15. Tumor necrosis factor (TNF) inhibits interleukin (IL)-1 and/or IL-6 stimulated synthesis of C-reactive protein (CRP) and serum amyloid A (SAA) in primary cultures of human hepatocytes

    Yap, S.H.; Moshage, H.J.; Hazenberg, B.P.C.; Roelofs, H.M.J.; Bijzet, J.; Limburg, P.C.; Aarden, L.A.; Van Rijswijk, M.H.

    1991-01-01

    Interleukin (IL)-1, IL-6 and tumor necrosis factor (TNF) are considered as important mediators for the modulation of liver synthesis of acute phase proteins. However, studies of the direct effect of individual or a combination of these cytokines on the synthesis of acute phase proteins in human hepa

  16. Analysis of peripheral amyloid precursor protein in Angelman Syndrome.

    Erickson, Craig A; Wink, Logan K; Baindu, Bayon; Ray, Balmiki; Schaefer, Tori L; Pedapati, Ernest V; Lahiri, Debomoy K

    2016-09-01

    Angelman Syndrome is a rare neurodevelopmental disorder associated with significant developmental and communication delays, high risk for epilepsy, motor dysfunction, and a characteristic behavioral profile. While Angelman Syndrome is known to be associated with the loss of maternal expression of the ubiquitin-protein ligase E3A gene, the molecular sequelae of this loss remain to be fully understood. Amyloid precursor protein (APP) is involved in neuronal development and APP dysregulation has been implicated in the pathophysiology of other developmental disorders including fragile X syndrome and idiopathic autism. APP dysregulation has been noted in preclinical model of chromosome 15q13 duplication, a disorder whose genetic abnormality results in duplication of the region that is epigenetically silenced in Angelman Syndrome. In this duplication model, APP levels have been shown to be significantly reduced leading to the hypothesis that enhanced ubiquitin-protein ligase E3A expression may be associated with this phenomena. We tested the hypothesis that ubiquitin-protein ligase E3A regulates APP protein levels by comparing peripheral APP and APP derivative levels in humans with Angelman Syndrome to those with neurotypical development. We report that APP total, APP alpha (sAPPα) and A Beta 40 and 42 are elevated in the plasma of humans with Angelman Syndrome compared to neurotypical matched human samples. Additionally, we found that elevations in APP total and sAPPα correlated positively with peripheral brain derived neurotrophic factor levels previously reported in this same patient cohort. Our pilot report on APP protein levels in Angelman Syndrome warrants additional exploration and may provide a molecular target of treatment for the disorder. © 2016 Wiley Periodicals, Inc. PMID:27327493

  17. Serum proteins analysis by capillary electrophoresis

    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...

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

    Jensen, Lisbeth Lund; Banner, Jytte; Ulhøi, Benedicte Parm;

    2013-01-01

    To develop and validate a scoring method for assessing β-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.......To develop and validate a scoring method for assessing β-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....

  19. The Impact of Serum Amyloid P-Component on Gene Expression in RAW264.7 Mouse Macrophages

    Dan Xi

    2016-01-01

    Full Text Available Serum amyloid P-component (SAP contributes to host defense and prevents fibrosis. Macrophages are the most abundant inflammatory cell type in atherosclerotic plaques. In the present study, using 3H-cholesterol-labeled counting radioactivity assay, we demonstrated that the apoAI-mediated cholesterol efflux in RAW264.7 macrophages was increased by SAP treatment in a time- and dose-dependent manner. We analyzed global gene expression changes upon SAP treatment using RNA sequencing. As a result, a total of 175 differentially expressed genes were identified, of which 134 genes were downregulated and 41 genes were upregulated in SAP treated cells compared to control cells. Quantitative RT-PCR analysis confirmed decreased expression of 5 genes and an increase in expression of 1 gene upon SAP treatment. Gene ontology analysis showed that genes involved in response to stimulus were significantly enriched in differentially expressed genes. Beyond protein-coding genes, we also identified 8 differentially expressed long noncoding RNAs. Our study may provide new insights into mechanisms underlying the functional role of SAP in macrophages.

  20. Distinct Fcγ receptors mediate the effect of serum amyloid p on neutrophil adhesion and fibrocyte differentiation.

    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 FcγRs, but the contribution of each FcγR is not fully understood. We found that aa Q55 and E126 in human SAP affect human fibrocyte differentiation and SAP binding to FcγRI. E126, K130, and Q128 affect neutrophil adhesion and SAP affinity for FcγRIIa. Q128 also affects phagocytosis by macrophages and SAP affinity for FcγRI. All the identified functionally significant amino acids in SAP form a binding site that is distinct from the previously described SAP-FcγRIIa binding site. Blocking FcγRI with an IgG-blocking Ab reduces the SAP effect on fibrocyte differentiation, and ligating FcγRIIa with Abs reduces neutrophil adhesion. Together, these results suggest that SAP binds to FcγRI on monocytes to inhibit fibrocyte differentiation, and binds to FcγRIIa on neutrophils to reduce neutrophil adhesion. PMID:25024390

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

    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

  2. Exploring new biological functions of amyloids: bacteria cell agglutination mediated by host protein aggregation.

    Marc Torrent

    Full Text Available Antimicrobial proteins and peptides (AMPs are important effectors of the innate immune system that play a vital role in the prevention of infections. Recent advances have highlighted the similarity between AMPs and amyloid proteins. Using the Eosinophil Cationic Protein as a model, we have rationalized the structure-activity relationships between amyloid aggregation and antimicrobial activity. Our results show how protein aggregation can induce bacteria agglutination and cell death. Using confocal and total internal reflection fluorescence microscopy we have tracked the formation in situ of protein amyloid-like aggregates at the bacteria surface and on membrane models. In both cases, fibrillar aggregates able to bind to amyloid diagnostic dyes were detected. Additionally, a single point mutation (Ile13 to Ala can suppress the protein amyloid behavior, abolishing the agglutinating activity and impairing the antimicrobial action. The mutant is also defective in triggering both leakage and lipid vesicle aggregation. We conclude that ECP aggregation at the bacterial surface is essential for its cytotoxicity. Hence, we propose here a new prospective biological function for amyloid-like aggregates with potential biological relevance.

  3. Evaluation of the amyloid beta-GFP fusion protein as a model of amyloid beta peptides-mediated aggregation: A study of DNAJB6 chaperone

    Rasha Mohamed Hussein; Rashed, Laila A

    2015-01-01

    Alzheimer’s disease is a progressive neurodegenerative disease characterized by the accumulation and aggregation of extracellular amyloid β (Aβ) peptides and intracellular aggregation of hyper-phosphorylated tau protein. Recent evidence indicates that accumulation and aggregation of intracellular amyloid β peptides may also play a role in disease pathogenesis. This would suggest that intracellular Heat Shock Proteins (HSP) that maintain cellular protein homeostasis might be candidates for dis...

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

    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.

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

    Turło, Agnieszka; Cywińska, Anna; Czopowicz, Michał; Witkowski, Lucjan; Niedźwiedź, Artur; Słowikowska, Malwina; Borowicz, Hieronim; Jaśkiewicz, 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 o...

  6. Proteomic evaluation of sheep serum proteins

    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.

  7. Organization and biology of the porcine serum amyloid A (SAA gene cluster: isoform specific responses to bacterial infection.

    Helle G Olsen

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

  8. Analysis of Amyloid Precursor Protein Function in Drosophila melanogaster.

    Cassar, Marlène; Kretzschmar, Doris

    2016-01-01

    The Amyloid precursor protein (APP) has mainly been investigated in connection with its role in Alzheimer's Disease (AD) due to its cleavage resulting in the production of the Aβ peptides that accumulate in the plaques characteristic for this disease. However, APP is an evolutionary conserved protein that is not only found in humans but also in many other species, including Drosophila, suggesting an important physiological function. Besides Aβ, several other fragments are produced by the cleavage of APP; large secreted fragments derived from the N-terminus and a small intracellular C-terminal fragment. Although these fragments have received much less attention than Aβ, a picture about their function is finally emerging. In contrast to mammals, which express three APP family members, Drosophila expresses only one APP protein called APP-like or APPL. Therefore APPL functions can be studied in flies without the complication that other APP family members may have redundant functions. Flies lacking APPL are viable but show defects in neuronal outgrowth in the central and peripheral nervous system (PNS) in addition to synaptic changes. Furthermore, APPL has been connected with axonal transport functions. In the adult nervous system, APPL, and more specifically its secreted fragments, can protect neurons from degeneration. APPL cleavage also prevents glial death. Lastly, APPL was found to be involved in behavioral deficits and in regulating sleep/activity patterns. This review, will describe the role of APPL in neuronal development and maintenance and briefly touch on its emerging function in circadian rhythms while an accompanying review will focus on its role in learning and memory formation. PMID:27507933

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

    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. Comparison of the aggregation of homologous β2-microglobulin variants reveals protein solubility as a key determinant of amyloid formation.

    Pashley, Clare L; Hewitt, Eric W; Radford, Sheena E

    2016-02-13

    The mouse and human β2-microglobulin protein orthologs are 70 % identical in sequence and share 88 % sequence similarity. These proteins are predicted by various algorithms to have similar aggregation and amyloid propensities. However, whilst human β2m (hβ2m) forms amyloid-like fibrils in denaturing conditions (e.g. pH2.5) in the absence of NaCl, mouse β2m (mβ2m) requires the addition of 0.3M NaCl to cause fibrillation. Here, the factors which give rise to this difference in amyloid propensity are investigated. We utilise structural and mutational analyses, fibril growth kinetics and solubility measurements under a range of pH and salt conditions, to determine why these two proteins have different amyloid propensities. The results show that, although other factors influence the fibril growth kinetics, a striking difference in the solubility of the proteins is a key determinant of the different amyloidogenicity of hβ2m and mβ2m. The relationship between protein solubility and lag time of amyloid formation is not captured by current aggregation or amyloid prediction algorithms, indicating a need to better understand the role of solubility on the lag time of amyloid formation. The results demonstrate the key contribution of protein solubility in determining amyloid propensity and lag time of amyloid formation, highlighting how small differences in protein sequence can have dramatic effects on amyloid formation. PMID:26780548

  11. The Effect of Storage Temperature and Time on the Concentrations of Bovine Serum Amyloid A and Its Mammary Associated Isoform

    Csilla Tóthová

    2012-01-01

    Full Text Available The objective of this study was to evaluate the effect of storage under various conditions on the concentrations of major bovine acute phase protein—serum amyloid A, and its mammary isoform. Blood samples were taken from seven clinically healthy calves, and milk samples from six clinically healthy dairy cows. The harvested blood serum and the milk samples were fractioned into aliquots. One aliquot was analyzed on the day of collection without storage. The second aliquots were stored at 4°C for 1 day, the remaining aliquots were kept frozen at −18°C for 2, 7, 14, and 21 days, and then analyzed. Blood serum was analyzed for serum amyloid A (SAA. The concentrations of mammary isoform of SAA (M-SAA were measured in milk samples. Over time, the concentrations of SAA in serum showed a tendency of significant decrease during storage at −18°C (P<0.01. Similarly, the values of M-SAA decreased significantly in samples maintained at freezer temperatures (P<0.001. In the refrigerated samples, we found non-significantly lower values of SAA, as well as M-SAA. Presented results indicate that the storage temperature and duration may markedly affect the concentrations of bovine SAA and M-SAA.

  12. iTRAQ technology-based identification of human peripheral serum proteins associated with depression.

    Wang, Q; Su, X; Jiang, X; Dong, X; Fan, Y; Zhang, J; Yu, C; Gao, W; Shi, S; Jiang, J; Jiang, W; Wei, T

    2016-08-25

    Clinical depression is one of the most common and debilitating psychiatric disorders and contributes to increased risks of disability and suicide. Differentially expressed serum proteins may serve as biomarkers for diagnosing depression. In this study, samples from depressed patients are aggregated into a pool (22×100μL serum was used) and samples from healthy volunteers are aggregated into the other pool (20×100μL serum was used). Isobaric tag for relative and absolute quantitation (iTRAQ) technology and tandem mass spectrometry were employed to screen for differentially expressed serum protein in two separate pools. We identified 472 proteins in the serum samples, and 154 of these presented differences in abundance between the depression and control groups. Ingenuity pathway analysis (IPA) was employed to identify the highest scoring proteins in signaling pathway networks. Finally, four differentially expressed proteins were validated by enzyme-linked immuno sorbent assay (ELISA). Proteomic studies revealed that levels of c-reaction protein (CRP), inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4), serum amyloid A1 (SAA1) and angiopoietin-like 3 (ANGPTL3) were substantially increased in depressed patients compared with the healthy control group. Therefore, these differentially expressed proteins may represent potential markers for the clinical diagnosis of depression. PMID:27268281

  13. Hyperhomocysteinemia Increases β-Amyloid by Enhancing Expression of γ-Secretase and Phosphorylation of Amyloid Precursor Protein in Rat Brain

    Zhang, Chang-E; Wei, Wei; Liu, Ying-Hua; Peng, Jun-Hua; Tian, Qing; Liu, Gong-Ping; ZHANG, YAO; Wang, Jian-Zhi

    2009-01-01

    Hyperhomocysteinemia and β-amyloid (Aβ) overproduction are critical etiological and pathological factors in Alzheimer disease, respectively; however, the intrinsic link between them is still missing. Here, we found that Aβ levels increased and amyloid precursor protein (APP) levels simultaneously decreased in hyperhomocysteinemic rats after a 2-week induction by vena caudalis injection of homocysteine. Concurrently, both the mRNA and protein levels of presenilin-1, a component of γ-secretase,...

  14. The Components of Flemingia macrophylla Attenuate Amyloid β-Protein Accumulation by Regulating Amyloid β-Protein Metabolic Pathway

    Yun-Lian Lin

    2012-01-01

    Full Text Available Flemingia macrophylla (Leguminosae is a popular traditional remedy used in Taiwan as anti-inflammatory, promoting blood circulation and antidiabetes agent. Recent study also suggested its neuroprotective activity against Alzheimer's disease. Therefore, the effects of F. macrophylla on Aβ production and degradation were studied. The effect of F. macrophylla on Aβ metabolism was detected using the cultured mouse neuroblastoma cells N2a transfected with human Swedish mutant APP (swAPP-N2a cells. The effects on Aβ degradation were evaluated on a cell-free system. An ELISA assay was applied to detect the level of Aβ1-40 and Aβ1-42. Western blots assay was employed to measure the levels of soluble amyloid precursor protein and insulin degrading enzyme (IDE. Three fractions of F. macrophylla modified Aβ accumulation by both inhibiting β-secretase and activating IDE. Three flavonoids modified Aβ accumulation by activating IDE. The activated IDE pool by the flavonoids was distinctly regulated by bacitracin (an IDE inhibitor. Furthermore, flavonoid 94-18-13 also modulates Aβ accumulation by enhancing IDE expression. In conclusion, the components of F. macrophylla possess the potential for developing new therapeutic drugs for Alzheimer's disease.

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

    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..

  16. Beta-protein deposition: a pathogenetic link between Alzheimer's disease and cerebral amyloid angiopathies.

    Coria, F; Prelli, F; Castaño, E M; Larrondo-Lillo, M; Fernandez-Gonzalez, J; van Duinen, S G; Bots, G T; Luyendijk, W; Shelanski, M L; Frangione, B

    1988-10-25

    Cerebral amyloid angiopathy (CAA) refers to a group of hereditary (hereditary cerebral hemorrhage with amyloidosis, HCHWA and sporadic (SCAA) disorders characterized by amyloid fibril deposition restricted to the leptomeningeal and cortical vasculature leading to recurrent hemorrhagic and/or ischemic accidents. On clinical and biochemical grounds, two forms of HCHWA can be distinguished. The amyloid subunit of the HCHWA of Icelandic origin is related to Cystatin C, while amyloid from patients of Dutch origin (HCHWA-D) is related to the beta-protein (or A4), the main component of vascular and plaque core amyloid in Alzheimer's disease (AD) and Down's syndrome (DS) [corrected]. SCAA is an increasingly recognized cause of stroke in normotensive individual amounting to 5-10% of all cerebrovascular accidents. We now report the isolation and partial amino acid sequence of the amyloid subunit from a case of SCAA and a new case of HCHWA-D. The recognition that a heterogeneous group of diseases are linked by similar pathological and chemical features suggests that diversity of etiological factors may promote a common pathogenetic mechanism leading to amyloid-beta (A beta) deposition, and open new ways of research in AD and CAA as they are related to dementia and stroke. PMID:3058268

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

    Eugène, Sarah; Xue, Wei-Feng; Robert, Philippe; Doumic, Marie

    2016-05-01

    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 model, from which closed form analytical results capable of describing and predicting the variability of nucleated amyloid assembly were derived. We also demonstrate the application of our results to inform experiments in a conceptually friendly and clear fashion. Our model offers a new perspective and paves the way for a new and efficient approach on extracting vital information regarding the key initial events of amyloid formation.

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

    Eugène, Sarah; Xue, Wei-Feng; Robert, Philippe; Doumic, Marie

    2016-05-01

    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 model, from which closed form analytical results capable of describing and predicting the variability of nucleated amyloid assembly were derived. We also demonstrate the application of our results to inform experiments in a conceptually friendly and clear fashion. Our model offers a new perspective and paves the way for a new and efficient approach on extracting vital information regarding the key initial events of amyloid formation. PMID:27155653

  19. Self-assembling of amyloid-like proteins

    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

  20. Self-assembling of amyloid-like proteins

    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

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

    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...

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

    Bech, Sara; Hjermind, Lena E; Salvesen, Lisette;

    2012-01-01

    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 fragments of amyloid precursor proteins in a cohort of patients with various PS.......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...

  3. Disease Transmission by Misfolded Prion-Protein Isoforms, Prion-Like Amyloids, Functional Amyloids and the Central Dogma.

    Daus, Martin L

    2016-01-01

    In 1982, the term "prions" (proteinaceous infectious particles) was coined to specify a new principle of infection. A misfolded isoform of a cellular protein has been described as the causative agent of a fatal neurodegenerative disease. At the beginning of prion research scientists assumed that the infectious agent causing transmissible spongiform encephalopathy (TSE) was a virus, but some unconventional properties of these pathogens were difficult to bring in line with the prevailing viral model. The discovery that prions (obviously devoid of any coding nucleic acid) can store and transmit information similarly to DNA was initially even denoted as being "heretical" but is nowadays mainly accepted by the scientific community. This review describes, from a historical point of view, how the "protein-only hypothesis" expands the Central Dogma. Definition of both, the prion principle and the Central Dogma, have been essential steps to understand information storage and transfer within and among cells and organisms. Furthermore, the current understanding of the infectivity of prion-proteins after misfolding is summarized succinctly. Finally, prion-like amyloids and functional amyloids, as found in yeast and bacteria, will be discussed. PMID:26742083

  4. Disease Transmission by Misfolded Prion-Protein Isoforms, Prion-Like Amyloids, Functional Amyloids and the Central Dogma

    Martin L. Daus

    2016-01-01

    Full Text Available In 1982, the term “prions” (proteinaceous infectious particles was coined to specify a new principle of infection. A misfolded isoform of a cellular protein has been described as the causative agent of a fatal neurodegenerative disease. At the beginning of prion research scientists assumed that the infectious agent causing transmissible spongiform encephalopathy (TSE was a virus, but some unconventional properties of these pathogens were difficult to bring in line with the prevailing viral model. The discovery that prions (obviously devoid of any coding nucleic acid can store and transmit information similarly to DNA was initially even denoted as being “heretical” but is nowadays mainly accepted by the scientific community. This review describes, from a historical point of view, how the “protein-only hypothesis” expands the Central Dogma. Definition of both, the prion principle and the Central Dogma, have been essential steps to understand information storage and transfer within and among cells and organisms. Furthermore, the current understanding of the infectivity of prion-proteins after misfolding is summarized succinctly. Finally, prion-like amyloids and functional amyloids, as found in yeast and bacteria, will be discussed.

  5. SERUM PROTEINS, TRANSAMINASES AND PHOSPHATASES IN MALNUTRITION

    H. Mohammadiha

    1976-07-01

    Full Text Available The levels of serum tota1 protein, albumin, transaminases and phosphatases were estimated in a group of children with severe Marasmus or mild malnutrition in order to identify some of the associated deficiencies in these syndromes. The biochemical pattern was similar in the normal and malnourished children.

  6. Dynamic changes of beta-amyloid protein deposition in hippocampus of female ovariectomized rats

    Huiqing Xie; Jianda Zhou; Shaodan Sun; Xuhong Li; Liming Deng; Fengmei Li

    2008-01-01

    BACKGROUND: To evaluate and summarize the effects of cerebral perfusion and vascular reserve on the treatment of SICAS. Recently, research on β-amyloid protein has focused on the regulatory effects of es-trogen or phytoestrogen on its deposition. However, there have been only a few reports on dynamic changes of β-amyloid protein deposition in hippocampus of ovariectomized rats.OBJECTIVE: To measureβ-amyloid protein deposition in the hippocampal formation of ovariectomized rats by using immunohistochemistry; to observe time-dependent dynamic changes. DESIGN: Randomized controlled animal study.SETTING: Third Xiangya Hospital of Central South University.MATERIALS: The experiment was carried out in the Central Laboratory of the Third Xiangya Hospital of Central South University from November 2005 to December 2006. Fifty healthy female Sprague Dawley (SD) rats, weighing (293 ± 10) g, were provided by the Animal Laboratory of Xiangya Medical College, Central South University. All rats had neither a childbearing history nor hepatic or renal disease, or skeletal deformity. Β-amyloid protein immunohistochemical kit was provided by Wuhan Boster Company. The ex-periment was in accordance with animal ethics standards.METHODS: All rats were randomly divided into five groups, including normal control group (n = 10), sham operation group (n = 10), and ovariectomized group (n = 30). After anesthesia in the ovariectomized group, the bilateral ovaries were separated and resected. The same volume of fat was resected in the sham operation group. Rats from the normal control group, however, did not receive any surgical treatments. Rats in the normal control group and sham operation group were sacrificed by anesthesia 7 weeks after surgery. Every ten rats from the ovariectomized group was respectively sacrificed at 7, 15, and 30 weeks after surgery. Immunohistochemistry was used to detectβ-amyloid protein deposition in hippocampal sections. Cell counting and gray value

  7. Specific Inhibition of β-Secretase Processing of the Alzheimer Disease Amyloid Precursor Protein

    Saoussen Ben Halima

    2016-03-01

    Full Text Available Development of disease-modifying therapeutics is urgently needed for treating Alzheimer disease (AD. AD is characterized by toxic β-amyloid (Aβ peptides produced by β- and γ-secretase-mediated cleavage of the amyloid precursor protein (APP. β-secretase inhibitors reduce Aβ levels, but mechanism-based side effects arise because they also inhibit β-cleavage of non-amyloid substrates like Neuregulin. We report that β-secretase has a higher affinity for Neuregulin than it does for APP. Kinetic studies demonstrate that the affinities and catalytic efficiencies of β-secretase are higher toward non-amyloid substrates than toward APP. We show that non-amyloid substrates are processed by β-secretase in an endocytosis-independent manner. Exploiting this compartmentalization of substrates, we specifically target the endosomal β-secretase by an endosomally targeted β-secretase inhibitor, which blocked cleavage of APP but not non-amyloid substrates in many cell systems, including induced pluripotent stem cell (iPSC-derived neurons. β-secretase inhibitors can be designed to specifically inhibit the Alzheimer process, enhancing their potential as AD therapeutics without undesired side effects.

  8. Fibronectin and serum amyloid P component stimulate C3b- and C3bi- mediated phagocytosis in cultured human monocytes

    1983-01-01

    Fibronectin (FN) and serum amyloid P component (SAP) markedly enhance phagocytosis mediated by the C3b and C3bi receptors of cultured human monocytes but not of granulocytes. (The C3b and C3bi receptors of granulocytes can be activated by treatment of these phagocytes with PMA.) Activation of monocyte C3 receptors by FN is developmentally regulated: Freshly explanted monocytes respond to FN with a small increase in C3 receptor-mediated phagocytosis while monocytes matured in culture exhibit a...

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

    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, ...

  10. Relevance of amyloid precursor-like protein 2 C-terminal fragments in pancreatic cancer cells

    PETERS, HALEY L.; Tuli, Amit; Wang, Xiaojian; Liu, Cuiling; Pan, Zenggang; Ouellette, Michel M.; Hollingsworth, Michael A.; MacDonald, Richard G.; Solheim, Joyce C.

    2012-01-01

    In some cellular systems, particularly neurons, amyloid precursor-like protein 2 (APLP2), and its highly homologous family member amyloid precursor protein (APP), have been linked to cellular growth. APLP2 and APP undergo regulated intramembrane proteolysis to produce C-terminal fragments. In this study, we found comprehensive expression of APLP2 C-terminal fragments in a panel of pancreatic cancer cell lines; however, APP C-terminal fragments were notably limited to the BxPC3 cell line. Exte...

  11. Augmented Senile Plaque Load in Aged Female β-Amyloid Precursor Protein-Transgenic Mice

    Callahan, Michael J.; Lipinski, William J.; Bian, Feng; Durham, Robert A.; Pack, Amy; Walker, Lary C.

    2001-01-01

    Transgenic mice (Tg2576) overexpressing human β-amyloid precursor protein with the Swedish mutation (APP695SWE) develop Alzheimer’s disease-like amyloid β protein (Aβ) deposits by 8 to 10 months of age. These mice show elevated levels of Aβ40 and Aβ42, as well as an age-related increase in diffuse and compact senile plaques in the brain. Senile plaque load was quantitated in the hippocampus and neocortex of 8- to 19-month-old male and female Tg2576 mice. In all mice, plaque burden increased m...

  12. Overexpression of amyloid precursor protein inhibits neurite outgrowth and disrupts cytoskeleton in N2a cells

    王泽芬; 王建枝

    2004-01-01

    @@ There is considerable evidence suggesting that altered metabolism of β-amyloid precursor protein (APP) and accumulation of its β-amyloid (Aβ) fragment are key features of Alzheimer's disease (AD). APP is a type Ⅰ integral membrane protein and consists of 695-770 amino acids encoded by differentially spliced mRNAs transcribed from a single gene located on human chromosome 21.1 The 695-amino acid APP is expressed preferentially in the brain. Aβ, the major component of senile plaques, is derived by proteolytic processing of APP by β-and γ-secretase and is constitutively released from most cells.

  13. Cellular prion protein expression is not regulated by the Alzheimer's amyloid precursor protein intracellular domain.

    Victoria Lewis

    Full Text Available There is increasing evidence of molecular and cellular links between Alzheimer's disease (AD and prion diseases. The cellular prion protein, PrP(C, modulates the post-translational processing of the AD amyloid precursor protein (APP, through its inhibition of the β-secretase BACE1, and oligomers of amyloid-β bind to PrP(C which may mediate amyloid-β neurotoxicity. In addition, the APP intracellular domain (AICD, which acts as a transcriptional regulator, has been reported to control the expression of PrP(C. Through the use of transgenic mice, cell culture models and manipulation of APP expression and processing, this study aimed to clarify the role of AICD in regulating PrP(C. Over-expression of the three major isoforms of human APP (APP(695, APP(751 and APP(770 in cultured neuronal and non-neuronal cells had no effect on the level of endogenous PrP(C. Furthermore, analysis of brain tissue from transgenic mice over-expressing either wild type or familial AD associated mutant human APP revealed unaltered PrP(C levels. Knockdown of endogenous APP expression in cells by siRNA or inhibition of γ-secretase activity also had no effect on PrP(C levels. Overall, we did not detect any significant difference in the expression of PrP(C in any of the cell or animal-based paradigms considered, indicating that the control of cellular PrP(C levels by AICD is not as straightforward as previously suggested.

  14. Staphylococcal Bap Proteins Build Amyloid Scaffold Biofilm Matrices in Response to Environmental Signals

    Taglialegna, Agustina; Navarro, Susanna; Ventura, Salvador; Garnett, James A.; Matthews, Steve; Penades, José R.; Lasa, Iñigo; Valle, Jaione

    2016-01-01

    Biofilms are communities of bacteria that grow encased in an extracellular matrix that often contains proteins. The spatial organization and the molecular interactions between matrix scaffold proteins remain in most cases largely unknown. Here, we report that Bap protein of Staphylococcus aureus self-assembles into functional amyloid aggregates to build the biofilm matrix in response to environmental conditions. Specifically, Bap is processed and fragments containing at least the N-terminus of the protein become aggregation-prone and self-assemble into amyloid-like structures under acidic pHs and low concentrations of calcium. The molten globule-like state of Bap fragments is stabilized upon binding of the cation, hindering its self-assembly into amyloid fibers. These findings define a dual function for Bap, first as a sensor and then as a scaffold protein to promote biofilm development under specific environmental conditions. Since the pH-driven multicellular behavior mediated by Bap occurs in coagulase-negative staphylococci and many other bacteria exploit Bap-like proteins to build a biofilm matrix, the mechanism of amyloid-like aggregation described here may be widespread among pathogenic bacteria. PMID:27327765

  15. Nox2-derived radicals contribute to neurovascular and behavioral dysfunction in mice overexpressing the amyloid precursor protein

    Park, Laibaik; Zhou, Ping; Pitstick, Rose; Capone, Carmen; Anrather, Josef; Norris, Erin H.; Younkin, Linda; Younkin, Steven; Carlson, George; McEwen, Bruce S.; Iadecola, Costantino

    2008-01-01

    Alterations in cerebrovascular regulation related to vascular oxidative stress have been implicated in the mechanisms of Alzheimer's disease (AD), but their role in the amyloid deposition and cognitive impairment associated with AD remains unclear. We used mice overexpressing the Swedish mutation of the amyloid precursor protein (Tg2576) as a model of AD to examine the role of reactive oxygen species produced by NADPH oxidase in the cerebrovascular alterations, amyloid deposition, and behavio...

  16. Effects of Low-Dose Pioglitazone on Serum Levels of Adiponectin, Dehydroepiandrosterone, Amyloid Beta Peptide, and Lipid Profile in Elderly Japanese People with Type 2 Diabetes

    Yuji Aoki

    2015-01-01

    Full Text Available This study was performed to see how pioglitazone at low doses could affect blood biomarkers related to atherosclerosis and aging. The effects of an add-on treatment with pioglitazone (15 mg for males and 7.5 mg for females for 6 months were assessed in 24 outpatients (12 males, 12 females with type 2 diabetes aged ≥ 70 years. As doses of sulfonylurea were reduced in 10 patients, no significant differences in HbA1c and glucose levels were seen. After the treatment, serum levels of HDL cholesterol, arachidonic acid (predominant in males, and high-molecular-weight adiponectin significantly increased. The level of dehydroepiandrosterone sulfate significantly decreased. No significant changes were seen in those of small dense LDL cholesterol, high-sensitivity C-reactive protein, and amyloid beta peptides 1–40 and 1–42. There was a slight but significant increase in body weight, but apparent adverse effects were not observed. In conclusion, pioglitazone at low doses increased serum adiponectin, HDL cholesterol, and arachidonic acid levels but decreased serum dehydroepiandrosterone level, not associated with glycemia, in elderly Japanese people with type 2 diabetes. An optimal dose of pioglitazone should be sought for to minimize its adverse effects and to fully exert its pleiotropic effects such as antiatherosclerotic and antiaging effects.

  17. Serum Amyloid A as a Marker of Persistent Inflammation and an Indicator of Cardiovascular and Renal Involvement in Patients with Rheumatoid Arthritis

    Bożena Targońska-Stępniak

    2014-01-01

    Full Text Available Objectives. Rheumatoid arthritis (RA is a systemic, inflammatory disease. Serum amyloid A (SAA is an acute-phase protein, involved in pathogenesis of atherosclerosis. The aim of the study was to assess serum concentration of SAA in RA patients, with reference to other inflammatory parameters and markers of extra-articular involvement. Methods. The study population consisted of 140 RA patients, low/moderate disease activity (L/MDA in 98 (70% patients and high disease activity (HDA in 42 (30%. Comprehensive clinical and laboratory assessment was performed with evaluation of electrocardiogram and carotid intima-media thickness. Results. The mean SAA concentration [327.0 (263.4 mg/L] was increased highly above the normal value, even in patients with L/MDA. Simultaneously, SAA was significantly higher in patients with HDA versus L/MDA. The mean SAA concentration was significantly higher in patients treated with glucocorticoids, was inversely associated with QTc duration, and was markedly higher in patients with atherosclerotic plaques, emphasizing increased CV risk. SAA was significantly higher in patients with increased cystatin-C level. Conclusions. In RA patients, high serum SAA concentration was strongly associated with activity of the disease and risk of CV and renal involvement. Recurrent assessment of SAA may facilitate searching patients with persistent inflammation and risk of extra-articular complications.

  18. Value of combining 64 multi-slice spiral computer tomography and serum amyloid A protein in surgical decision-making in rectal cancer%多层螺旋CT联合血清淀粉样蛋白A术前评估直肠癌在外科决策中的价值

    汪晓东; 吕东昊; 宋欢; 秦昌龙; 吴俊华; 李臻辉; 李立

    2009-01-01

    目的 探讨64排多层螺旋CT(MSCT)和血清淀粉样蛋白A(SAA)联合术前评估进行直肠癌术前分期的准确性及其临床应用价值.方法 前瞻性纳入2007年10月至2008年10月期间住院的225例直肠癌患者,将患者随机分为MSCT组和MSCT与SAA联合组,联合组术前行MSCT和SAA联合评估,MSCT组术前只行MSCT评估.分别将两组术前T、N、M、TNM分期准确度进行比较,并比较两组手术方案的预测符合率.结果 本研究实际纳入病例225例,MSCT和SAA联合组110例,MSCT组115例,两组基线情况具有可比性.联合组术前T、N、M和TNM分期的准确度分别为87.3%、85.2%、100%和86.4%,MSCT组的准确度分别为85.2%、67.0%、100%和66.1%;两组术前N分期和TNM分期准确度差异具有统计学意义(P=0.009、0.001).两组手术方案的预测符合率分别为94.7%和81.7%,差异具有统计学意义(P=0.003).结论 MSCT和SAA联合评估的策略可以提高直肠癌患者术前分期N、TNM的准确性,并可提高预测手术方案的符合率.%Objective To determine the accuracy and clinical value of combining 64 multi-slice spiral computer tomography (MSCT) and serum amyloid A protein (SAA) in the preoperative staging of rectal cancer.Methods Prospectively enrolled patients with rectal cancer from October 2007 to October 2008.The patients were randomly assigned into two groups:MSCT and SAA combined group:both MSCT and SAA combinative assessment were performed for preoperative evaluation; MSCT group:only MSCT was performed preoperatively for tumor staging.The accuracy of the preoperative T,N,M,and TNM staging and the concordance rate of predictive operative strategy were compared between the two groups.Results Total of 225 cases with rectal cancer were enrolled in this study.There were 110 cases in MSCT and SAA combined group and 115 cases in MSCT group.The baseline characteristics was comparable between the two groups.For MSCT and SAA combined group,the accuracies of

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

    Zheng, Lin; Kågedal, Katarina; Dehvari, Nodi; Benedikz, Eirikur; Cowburn, Richard; Marcusson, Jan; Terman, Alexei

    2009-01-01

    There is increasing evidence for the toxicity of intracellular amyloid beta-protein (Abeta) to neurons and the involvement of lysosomes in this process in Alzheimer disease (AD). We have recently shown that oxidative stress, a recognized determinant of AD, enhances macroautophagy and leads to int...

  20. Diagnostic performance of amyloid A protein quantification in fat tissue of patients with clinical AA amyloidosis

    Hazenberg, Bouke P. C.; Bijzet, Johannes; Limburg, Pieter C.; Skinner, Martha; Hawkins, Philip N.; Butrimiene, Irena; Livneh, Avi; Lesnyak, Olga; Nasonov, Evgeney L.; Filipowicz-Sosnowska, Anna; Guel, Ahmet; Merlini, Giampaolo; Wiland, Piotr; Oezdogan, Huri; Gorevic, Peter D.; Ben Maiz, Hedi; Benson, Merrill D.; Direskeneli, Haner; Kaarela, Kalevi; Garceau, Denis; Hauck, Wendy; van Rijswijk, Martin

    2007-01-01

    Objective. Amyloid A protein quantification in fat tissue is a new immunochemical method for detecting AA amyloidosis, a rare but serious disease. The objective was to assess diagnostic performance in clinical AA amyloidosis. Methods. Abdominal subcutaneous fat tissue of patients with AA amyloidosis

  1. Amyloid domains in the cell nucleus controlled by nucleoskeletal protein lamin B1 reveal a new pathway of mercury neurotoxicity

    Florian Arnhold

    2015-02-01

    Full Text Available Mercury (Hg is a bioaccumulating trace metal that globally circulates the atmosphere and waters in its elemental, inorganic and organic chemical forms. While Hg represents a notorious neurotoxicant, the underlying cellular pathways are insufficiently understood. We identify amyloid protein aggregation in the cell nucleus as a novel pathway of Hg-bio-interactions. By mass spectrometry of purified protein aggregates, a subset of spliceosomal components and nucleoskeletal protein lamin B1 were detected as constituent parts of an Hg-induced nuclear aggregome network. The aggregome network was located by confocal imaging of amyloid-specific antibodies and dyes to amyloid cores within splicing-speckles that additionally recruit components of the ubiquitin-proteasome system. Hg significantly enhances global proteasomal activity in the nucleus, suggesting that formation of amyloid speckles plays a role in maintenance of protein homeostasis. RNAi knock down showed that lamin B1 for its part regulates amyloid speckle formation and thus likewise participates in nuclear protein homeostasis. As the Hg-induced cascade of interactions between the nucleoskeleton and protein homeostasis reduces neuronal signalling, amyloid fibrillation in the cell nucleus is introduced as a feature of Hg-neurotoxicity that opens new avenues of future research. Similar to protein aggregation events in the cytoplasm that are controlled by the cytoskeleton, amyloid fibrillation of nuclear proteins may be driven by the nucleoskeleton.

  2. A Survey of Membrane Proteins in Human Serum

    Dung, Nguyen Tien; Chi, Phan Van

    2012-01-01

    Serum and membrane proteins are two of the most attractive targets for proteomic analysis. Previous membrane protein studies tend to focus on tissue sample, while membrane protein studies in serum are still limited. In this study, an analysis of membrane proteins in normal human serum was carried out. Nano-liquid chromatography-electrospray ionization mass spectrometry (NanoLC-ESI-MS/MS) and bioinformatics tools were used to identify membrane proteins. Two hundred and seventeen membrane prote...

  3. Membrane Incorporation, Channel Formation, and Disruption of Calcium Homeostasis by Alzheimer's β-Amyloid Protein

    Masahiro Kawahara

    2011-01-01

    Full Text Available Oligomerization, conformational changes, and the consequent neurodegeneration of Alzheimer's β-amyloid protein (AβP play crucial roles in the pathogenesis of Alzheimer's disease (AD. Mounting evidence suggests that oligomeric AβPs cause the disruption of calcium homeostasis, eventually leading to neuronal death. We have demonstrated that oligomeric AβPs directly incorporate into neuronal membranes, form cation-sensitive ion channels (“amyloid channels”, and cause the disruption of calcium homeostasis via the amyloid channels. Other disease-related amyloidogenic proteins, such as prion protein in prion diseases or α-synuclein in dementia with Lewy bodies, exhibit similarities in the incorporation into membranes and the formation of calcium-permeable channels. Here, based on our experimental results and those of numerous other studies, we review the current understanding of the direct binding of AβP into membrane surfaces and the formation of calcium-permeable channels. The implication of composition of membrane lipids and the possible development of new drugs by influencing membrane properties and attenuating amyloid channels for the treatment and prevention of AD is also discussed.

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

    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

  5. Reexamining Alzheimer's Disease: Evidence for a Protective Role for AmyloidProtein Precursor and Amyloid

    Castellani, Rudy J.; Lee, Hyoung-gon; Siedlak, Sandra L.; Nunomura, Akihiko; Hayashi, Takaaki; Nakamura, Masao; Zhu, Xiongwei; Perry, George; Smith, Mark A.

    2009-01-01

    Alzheimer's disease (AD) is an age-related neurodegenerative disease characterized clinically by cognitive decline and pathologically by the accumulation of amyloid-β-containing senile plaques and neurofibrillary tangles. A great deal of attention has focused on amyloid-β as the major pathogenic mechanisms with the ultimate goal of using amyloid-β lowering therapies as an avenue of treatment. Unfortunately, nearly a quarter century later, no tangible progress has been offered, whereas spectac...

  6. Value of serum β amyloid protein and tau protein in early diagnosis of subcortical ischemic vascular dementia%血清β-淀粉样蛋白与tau蛋白在皮质下缺血性血管性痴呆早期诊断的应用价值

    刘扬; 孙中武

    2011-01-01

    Objective:To explore the value of serum β amydoid protein(Aβ) and tau(tau) protein in carly diagnosis of subcortical ischemic vascular dementia(SIVD). Methods: ELISA method was used to detect the levels of serum Aβ38, Aβ40, Aβ42, tau protein and cxcessive phosphorylated tau protein( p-tau) in 38 patients with SIVD,42 patients with mild cognitive impairment accompanicd by subcortical vascular features( MCI-V) and 36 controls. Results :The Aβ40 level of SIVD group was significantly higher than that of the other two groups(P < 0.01 ) ,and the Aβ40 level of MCI-V group was higher than that of the controls(P < 0.05) ;The levels of Aβ38 and Aβ42 did not differ among the three groups(P > 0.05). The tau level of SIVD group was significantly higher than that of the other two groups ( P < 0.01 ) , and the tau level of MCI-V group was higher than that of the controls ( P < 0.05). The p-tau level of SIVD group was significantly higher than that of the MCI-V group and the controls(P < 0.05). Conclusions :The levels of the serum Aβ40 and tau protein may act as meaningful biomarkers in early diagnosis of SIVD.%目的:探讨血清β-淀粉样蛋白(Aβ)与tau蛋白在皮质下缺血性血管性痴呆(SIVD)早期诊断中的应用价值.方法:采用ELISA法分别检测38例SIVD患者、42例伴皮层下血管性特征的轻度认知功能损害(MCI-V)患者以及36名正常对照者的血清Aβ38、Aβ40、Aβ42、总tau(tau)蛋白和磷酸化tau(p-tau)蛋白的水平.结果:SIVD组的Aβ40水平均显著高于MCI-V组和对照组(P0.05).SIVD组的tau水平均显著高于MCI-V组和对照组(P<0.01),MCI-V组高于对照组(P<0.05);SIVD组p-tau水平均高于MCI-V组和对照组(P<0.05).结论:血清Aβ40和tau蛋白可以作为SIVD早期诊断的生物学指标.

  7. 99mTc-MAMA-chrysamine G, a probe for beta-amyloid protein of Alzheimer's disease

    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.)

  8. Amyloid β-protein, Cystatin C and Cathepsin B as Biomarkers of Alzheimer's Disease

    Sundelöf, Johan

    2010-01-01

    It is suggested that Alzheimer’s disease (AD) is caused by an imbalance between production, degradation and clearance of the amyloid-β (Aβ) protein. This imbalance leads to aggregation of Aβ and tau proteins and neurodegeneration in the brain. Today there is increasing evidence that the balance between the protease cathepsin B and the protease inhibitor cystatin C affects the tendency for Aβ to aggregate. The primary aim of this thesis was to investigate Aβ, cystatin C and cathepsin B levels ...

  9. Development of new fusion proteins for visualizing amyloid-β oligomers in vivo

    Tomoyo Ochiishi; Motomichi Doi; Kazuhiko Yamasaki; Keiko Hirose; Akira Kitamura; Takao Urabe; Nobutaka Hattori; Masataka Kinjo; Tatsuhiko Ebihara; Hideki Shimura

    2016-01-01

    The intracellular accumulation of amyloid-β (Aβ) oligomers critically contributes to disease progression in Alzheimer’s disease (AD) and can be the potential target of AD therapy. Direct observation of molecular dynamics of Aβ oligomers in vivo is key for drug discovery research, however, it has been challenging because Aβ aggregation inhibits the fluorescence from fusion proteins. Here, we developed Aβ1-42-GFP fusion proteins that are oligomerized and visualize their dynamics inside cells ev...

  10. Vitamin k3 inhibits protein aggregation: Implication in the treatment of amyloid diseases

    Alam, Parvez; Chaturvedi, Sumit Kumar; Siddiqi, Mohammad Khursheed; Rajpoot, Ravi Kant; Ajmal, Mohd Rehan; Zaman, Masihuz; Khan, Rizwan Hasan

    2016-01-01

    Protein misfolding and aggregation have been associated with several human diseases such as Alzheimer’s, Parkinson’s and familial amyloid polyneuropathy etc. In this study, anti-fibrillation activity of vitamin k3 and its effect on the kinetics of amyloid formation of hen egg white lysozyme (HEWL) and Aβ-42 peptide were investigated. Here, in combination with Thioflavin T (ThT) fluorescence assay, circular dichroism (CD), transmission electron microscopy and cell cytotoxicity assay, we demonstrated that vitamin k3 significantly inhibits fibril formation as well as the inhibitory effect is dose dependent manner. Our experimental studies inferred that vitamin k3 exert its neuro protective effect against amyloid induced cytotoxicity through concerted pathway, modifying the aggregation formation towards formation of nontoxic aggregates. Molecular docking demonstrated that vitamin k3 mediated inhibition of HEWL and Aβ-42 fibrillogenesis may be initiated by interacting with proteolytic resistant and aggregation prone regions respectively. This work would provide an insight into the mechanism of protein aggregation inhibition by vitamin k3; pave the way for discovery of other small molecules that may exert similar effect against amyloid formation and its associated neurodegenerative diseases. PMID:27230476

  11. Expression of Serum Amyloid A Transcripts in Human Bone Tissues, Differentiated Osteoblast-Like Stem Cells and Human Osteosarcoma Cell Lines

    Kovacevic, Alenka; Hammer, Astrid; Stadelmeyer, Elke; Windischhofer, Werner; Sundl, Monika; Ray, Alpana; Schweighofer, Natascha; Friedl, Gerald; Windhager, Reinhard; Sattler, Wolfgang; Malle, Ernst

    2016-01-01

    Although the liver is the primary site of cytokine-mediated expression of acute-phase serum amyloid A (SAA) protein, extrahepatic production has also been reported. Besides its role in amyloidosis and lipid homeostasis during the acute-phase, SAA has recently been assumed to contribute to bone and cartilage destruction. However, expression of SAA in human osteogenic tissue has not been studied. Therefore, we first show that SAA1 (coding for the major SAA isoform) but not SAA2 transcripts are expressed in human trabecular and cortical bone fractions and bone marrow. Next, we show expression of (i) IL-1, IL-6, and TNF receptor transcripts; (ii) the human homolog of SAA-activating factor-1 (SAF-1, a transcription factor involved in cytokine-mediated induction of SAA genes); and (iii) SAA1/2 transcripts in non-differentiated and, to a higher extent, in osteoblast-like differentiated human mesenchymal stem cells. Third, we provide evidence that human osteoblast-like cells of tumor origin (MG-63 and SAOS-2) express SAF-1 under basal conditions. SAA1/2 transcripts are expressed under basal conditions (SAOS-2) and cytokine-mediated conditions (MG-63 and SAOS-2). RT-PCR, Western blot analysis, and immunofluorescence technique confirmed cytokine-mediated expression of SAA on RNA and protein level in osteosarcoma cell lines while SAA4, a protein of unknown function, is constitutively expressed in all osteogenic tissues investigated. PMID:17849429

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

    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.

  13. Differential regulation of amyloid-β-protein mRNA expression within hippocampal neuronal subpopulations in Alzheimer disease

    The authors have mapped the neuroanatomical distribution of amyloid-β-protein mRNA within neuronal subpopulations of the hippocampal formation in the cynomolgus monkey (Macaca fascicularis), normal aged human, and patients with Alzheimer disease. Amyloid-β-protein mRNA appears to be expressed in all hippocampal neurons, but at different levels of abundance. In the central nervous system of monkey and normal aged human, image analysis shows that neurons of the dentate gyrus and cornu Ammonis fields contain a 2.5-times-greater hybridization signal than is present in neurons of the subiculum and entorhinal cortex. In contrast, in the Alzheimer disease hippocampal formation, the levels of amyloid-β-protein mRNA in the cornu Ammonis field 3 and parasubiculum are equivalent. These findings suggest that within certain neuronal subpopulations cell type-specific regulation of amyloid-β-protein gene expression may be altered in Alzheimer disease

  14. Comparison of the aggregation of homologous β2-microglobulin variants reveals protein solubility as a key determinant of amyloid formation

    Pashley, Clare L.; Hewitt, Eric W.; Sheena E. Radford

    2016-01-01

    The mouse and human β2-microglobulin protein orthologs are 70 % identical in sequence and share 88 % sequence similarity. These proteins are predicted by various algorithms to have similar aggregation and amyloid propensities. However, whilst human β2m (hβ2m) forms amyloid-like fibrils in denaturing conditions (e.g. pH 2.5) in the absence of NaCl, mouse β2m (mβ2m) requires the addition of 0.3 M NaCl to cause fibrillation. Here, the factors which give rise to this difference in amyloid propens...

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

    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 α-synuclein yielded 88–97 % correctness for the backbone and side-chain assignments that are classified as self-consistent by the algorithm, and 77–90 % correctness if also assignments classified as tentative by the algorithm are included

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

    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.

  17. Serum amyloid A1 secreted from UV-irradiated keratinocytes induces matrix metalloproteinase-1 in fibroblasts through toll-like receptor 4.

    Han, Sangbum; Jin, Seon-Pil; Oh, Jang-Hee; Seo, Eun-Young; Park, Chi-Hyun; Yoon, Hyun-Sun; Lee, Dong Hun; Chung, Jin Ho

    2016-07-01

    Ultraviolet (UV) irradiation on skin triggers photoageing-related phenotypes such as formation of wrinkles. UV ray upregulates matrix metalloproteinase-1 (MMP-1), which in turn degrades extracellular matrix proteins, mostly collagens. Serum amyloid A1 (SAA1) is an acute-phase protein of which plasma concentration increases in response to inflammation. Although the expression of SAA1 in the skin was reported, its function in the skin is yet to be studied. In this research, we found that the expression of SAA1 was increased in acute UV-irradiated buttock skin and photoaged forearm skin in vivo. UV irradiation also increased SAA1 in normal human epidermal keratinocytes (NHEK), and treatment of recombinant human SAA1 (rhSAA1) induced MMP-1 in normal human dermal fibroblasts (NHDF) but not in NHEK. Next, we demonstrated that NHDF treated with UV-irradiated keratinocyte-conditioned media showed the increased MMP-1 expression; however, this increase of MMP-1 in NHDF was inhibited by knockdown of SAA1 in NHEK. In addition, knockdown of Toll-like receptor 4 (TLR4) inhibited rhSAA1-induced MMP-1 expression in NHDF. Taken together, our data showed that UV-induced SAA1 production in NHEK, and this secreted SAA1 induced MMP-1 expression in NHDF in a paracrine manner through TLR4 signalling pathway. Therefore, our results suggest that SAA1 can be a potential mediator for UV-induced MMP-1 expression in human skin. PMID:26900010

  18. Amyloid precursor protein selective gamma-secretase inhibitors for treatment of Alzheimer's disease

    Basi, Guriqbal S; Hemphill, Susanna; Brigham, Elizabeth F.; Liao, Anna; Aubele, Danielle L; Baker, Jeanne; Barbour, Robin; Bova, Michael; Chen, Xiao-Hua; Dappen, Michael S; Eichenbaum, Tovah; Goldbach, Erich; Hawkinson, Jon; Lawler-Herbold, Rose; Hu, Kang

    2010-01-01

    Introduction Inhibition of gamma-secretase presents a direct target for lowering Aβ production in the brain as a therapy for Alzheimer's disease (AD). However, gamma-secretase is known to process multiple substrates in addition to amyloid precursor protein (APP), most notably Notch, which has limited clinical development of inhibitors targeting this enzyme. It has been postulated that APP substrate selective inhibitors of gamma-secretase would be preferable to non-selective inhibitors from a ...

  19. Phenolic Compounds Prevent Amyloid β-Protein Oligomerization and Synaptic Dysfunction by Site-specific Binding*

    Ono, K.; Li, L.; Takamura, Y; Yoshiike, Y; L. Zhu; Han, F.; Mao, X; Ikeda, T; Takasaki, JI; Nishijo, H; Takashima, A.; Teplow, DB; Zagorski, MG; Yamada, M.

    2012-01-01

    Cerebral deposition of amyloid β protein (Aβ) is an invariant feature of Alzheimer disease (AD), and epidemiological evidence suggests that moderate consumption of foods enriched with phenolic compounds reduce the incidence of AD. We reported previously that the phenolic compounds myricetin (Myr) and rosmarinic acid (RA) inhibited Aβ aggregation in vitro and in vivo. To elucidate a mechanistic basis for these results, we analyzed the effects of five phenolic compounds in the Aβ aggregation pr...

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

    Christensen, Michelle Brønniche; Sørensen, Jens Christian; Jacobsen, Stine;

    2013-01-01

    was achieved in the present study, but findings important for future investigations were made. The study suggested that SAA is not exclusively hydrophobic, but appears less hydrophobic when interacting with other serum components. These results suggest more complex aspects of solubility than previously...

  1. Effects of exercises on expressions of serum amyloid A protein and aorta resistin-like molecules α in insulin-resistant rats%胰岛素抵抗大鼠血清淀粉样蛋白A、主动脉抵抗素样分子α的表达及运动干预作用

    李芳芳; 张黎军

    2013-01-01

    Objective To investigate the effects of exercises on expressions of serum amyloid A protein(SAA)and resistin-like molecules α(RELMα)in aorta of insulin-resistant(IR)rats induced by diets.Method Taking the completely randomized method,a total of 30 Wistar rats were divided into 3 groups:normal control group(n =10)fed with normal diet,IR and exercises groups with high sugar and high fat diet(10 rats in each group).Eight weeks later,the index of insulin resistance was assessed to confirm that models were successfully made.The three groups were continually fed with the same diet as before,while the exercise group was administered with swimming training for eight weeks in addition.At the end of sixteen weeks experiment,Rats' blood were sampled for measuring the levels of triglyceride(TG),total cholesterol (TC),high-density lipeprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),glucose (FBG),SAA,aorta RELMα mRNA and insulin(FINS)and the body weight(BW)were measured.The homeostasis model assessment index of IR(HOMA-IR)were calculated.Haematoxylin and eosin stain method was applied to observe morphology characteristics of aorta in groups.Difference of measurement data was compared with single factor analysis of variance.Results The levels of BW,FBG,FINS,HOMA-IR,TC,TG,LDL-C,SAA,RELMα mRNA in IR group were higher than those in control group(t =-20.666 ~-3.681,all P < 0.05),and the number of foam cell increased well(t =-20.596,P < 0.05),while the levels of HDL-C were lower(t =8.950,P < 0.05).The endothelial in the IR group were in disorder,and neointimal hyperplasia was found.After the intervention of exercise,the levels of SAA,RELMα mRNA,BW,FBG,FINS,HOMA-IR,TC,TG,LDL-C excercises group were decreased than those in IR group (t =2.524 ~ 8.640,P < 0.05),and the number of foam cell decreased well(t =11.520,P < 0.05),while the levels of HDL-C were higher(t =-2.094,P =0.05).Conclusion RELMα,SAA is relate to IR,aortic inflammation closely

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

    Nielsen, Morten S; Gustafsen, Camilla; Madsen, Peder;

    2007-01-01

    -formation with the amyloid precursor protein it downregulates generation of Alzheimer's disease-associated Abeta-peptide. The receptor is mainly located in vesicles, suggesting a function in protein sorting and transport. Here we examined SorLA's trafficking using full-length and chimeric receptors and find that......-deficient cells established that the AP-1 adaptor complex is essential to SorLA's transport between Golgi membranes and endosomes. Our results further implicate the GGA proteins in SorLA trafficking and provide evidence that SNX1 and Vps35, as parts of the retromer complex or possibly in a separate context, are...

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

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

    2008-01-01

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

  4. Reference Values for Serum Proteins of Common Laboratory Rodent Strains

    Zaias, Julia; Mineau, Martha; Cray, Carolyn; Yoon, David; Altman, Norman H

    2009-01-01

    Protein electrophoresis is a common proven technique to determine the protein components of plasma or serum in human, veterinary, and laboratory animal medicine. Changes in albumin and globulin protein levels can provide early and valuable diagnostic and prognostic information. Here we describe a preliminary analysis of the distribution of serum protein fractions in adult BALB/c, C57BL/6, and CD1 mice and Sprague-Dawley rats and describe the changes in protein values from birth to maturity in...

  5. [Hereditary amyloid cardiomyopathy related to a mutation at transthyretin protein number 111. A clinical, genetic and echocardiographic study of an affected Danish family].

    Svendsen, I H; Steensgaard-Hansen, F; Nordvåg, B Y

    1999-09-01

    Amyloidosis is a group of diseases characterized by amyloid deposition in various tissues. The diseases can roughly be divided into hereditary and non-hereditary forms. The hereditary forms are related to a mutation in the serum protein transthyretin which is produced mainly in the liver. The inheritance is autosomal dominant. A family in Denmark has earlier been described as having inherited cardiac amyloidosis with a mutation at amino acid number 111 in the transthyretin protein. The family now has been re-examined because of new diagnostic and therapeutic possibilities. The aims of the study were to identify carriers and non-carriers of the mutant transthyretin methionine 111 linked familial amyloid disease, to detect early signs of the restrictive cardiomyopathy and other clinical manifestations of this disease. Clinical, echocardiographic and genetic examination was carried out. Out of 125 living family members, 99 were available for examination. Twenty-five persons were heterozygous carriers of the mutant transthyretin methionine 111 genotype, while 74 were non-carriers. Eight carriers, all above the age of 35, showed echocardiographic abnormalities suggestive of developing or manifest restrictive cardiomyopathy. Nine carriers had carpal tunnel syndrome as opposed to none of the non-carriers. It is concluded that for early detection of familial amyloid cardiomyopathy, echocardiography is the investigation of choice. The first sign is diastolic dysfunction detected as an abnormal relaxation pattern. Carpal tunnel syndrome appears to be the earliest presenting clinical symptom. Early liver transplantation seems to be curative. PMID:10489791

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

    Agnieszka Turło

    Full Text Available 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.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.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.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.

  7. Estrogen stimulates release of secreted amyloid precursor protein from primary rat cortical neurons via protein kinase C pathway

    Sun ZHANG; Ying HUANG; Yi-chun ZHU; Tai YAO

    2005-01-01

    Aim: To investigate the mechanism of the action of estrogen, which stimulates the release of secreted amyloid precursor protein α (sAPPα) and decreases the gen eration of amyloidprotein (Aβ), a dominant component in senile plaques in the brains of Alzheimer's disease patients. Methods: Experiments were carried out inprimary rat cortical neurons, and Western blot was used to detect sAPPα in aculture medium and the total amount of cellular amyloid precursor protein (APP) in neurons. Results: 17β-Estradiol (but not 17α-estradiol) and β-estradiol 6-(Ocarboxymethyl) oxime: BSA increased the secretion of sAPPα and this effect was blocked by protein kinase C (PKC) inhibitor calphostin C, but not by the classical estrogen receptor antagonist ICI 182,780. Meanwhile, 17β-estradiol did not alter the synthesis of cellular APP. Conclusion: The effect of 17β-estradiol on sAPPα secretion is likely mediated through the membrane binding sites, and needs molecular configuration specificity of the ligand. Furthermore, the action of the PKC dependent pathway might be involved in estrogen-induced sAPPα secretion.

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

    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.

  9. Experimentally Derived Structural Constraints for Amyloid Fibrils of Wild-Type Transthyretin

    Bateman, David A.; Tycko, Robert; Wickner, Reed B.

    2011-01-01

    Transthyretin (TTR) is a largely β-sheet serum protein responsible for transporting thyroxine and vitamin A. TTR is found in amyloid deposits of patients with senile systemic amyloidosis. TTR mutants lead to familial amyloidotic polyneuropathy and familial amyloid cardiomyopathy, with an earlier age of onset. Studies of amyloid fibrils of familial amyloidotic polyneuropathy mutant TTR suggest a structure similar to the native state with only a simple opening of a β-strand-loop-strand region e...

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

    Sennvik, Kristina; Bogdanovic, N; Volkmann, Inga; Fastbom, J; Benedikz, Eirikur

    2004-01-01

    (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......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...

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

    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.

  12. Progress in the development of therapeutic antibodies targeting prion proteins and β-amyloid peptides

    2010-01-01

    Prion diseases and Alzheimer’s disease (AD) are characterized by protein misfolding, and can lead to dementia. However, prion diseases are infectious and transmissible, while AD is not. The similarities and differences between these diseases have led researchers to perform comparative studies. In the last 2 decades, progress has been made in immunotherapy using anti-prion protein and anti-β-amyloid antibodies. In this study, we review new ideas and strategies for therapeutic antibodies targeting prion diseases and AD through conformation dependence.

  13. Physiological role for amyloid precursor protein in adult experience-dependent plasticity.

    Marik, Sally A; Olsen, Olav; Tessier-Lavigne, Marc; Gilbert, Charles D

    2016-07-12

    Changes in neural circuits after experience-dependent plasticity are brought about by the formation of new circuits via axonal growth and pruning. Here, using a combination of electrophysiology, adeno-associated virus-delivered fluorescent proteins, analysis of mutant mice, and two-photon microscopy, we follow long-range horizontally projecting axons in primary somatosensory cortex before and after selective whisker plucking. Whisker plucking induces axonal growth and pruning of horizontal projecting axons from neurons located in the surrounding intact whisker representations. We report that amyloid precursor protein is crucial for axonal pruning and contributes in a cell autonomous way. PMID:27354516

  14. Epigenetic Induction of EGR-1 Expression by the Amyloid Precursor Protein during Exposure to Novelty

    Hendrickx, Aurélie; Pierrot, Nathalie; Tasiaux, Bernadette; Schakman, Olivier; Brion, Jean-Pierre; Kienlen-Campard, Pascal; De Smet, Charles; Octave, Jean-Noël

    2013-01-01

    Following transcriptome comparison of primary cultures isolated from brain of mice expressing or not the amyloid precursor protein APP, we found transcription of the EGR-1 gene to be regulated by APP. In primary cultures of cortical neurons, APP significantly down regulated EGR-1 expression at both mRNA and protein levels in a γ-secretase independent manner. The intracellular domain of APP did not interact with EGR-1 gene promoter, but enrichment of acetylated histone H4 at the EGR-1 promoter...

  15. Serum acute phase proteins in cows with SARA (Subacute Ruminal Acidosis suspect

    C. Cannizzo

    2012-02-01

    Full Text Available The aim of this study was to evaluate the variations of Acute Phase Proteins (APPs and other blood constituents during the onset of the sub-acute ruminal acidosis (SARA pathological status. A total of 108 cows from 12 dairy herds were randomly selected and divided into three Groups of 36 animals each. All animals were subjected to a rumenocentesis. Group A was composed by subjects with a rumen pH>5.8, Group B was composed by subjects with a rumen pH ≤5.5≤5.8 and Group C was composed by subjects with a rumen pH<5.5. Blood samples were collected by jugular venipuncture and Haptoglobin (Hp, Serum Amyloid A (SAA, Total Proteins, Albumin and White Blood Cells (WBC were determined. One-way ANOVA showed a statistical significance on Rumen pH, Hp, SAA. SARA seems not stimulate the APPs production from liver.

  16. Palmitoylation and amyloid fibril formation of lung surfactant protein C

    Gustafsson, Magnus

    2000-01-01

    Lung surfactant is a mixture of lipids and a few proteins, of which surfactant proteins (SP)-B and SP-C are lipophilic. Surfactant is essential for the reduction of surface tension at the alveolar air/liquid interface. The extremely hydrophobic SP-C is a 35-residue transmembraneous [alpha]-helical peptide containing a poly-Val stretch and two palmitoylated Cys residues. In this thesis the structural and functional importance of the SP-C palmitoyl groups and the poly-Val heli...

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

    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 Aβ1−40 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 Aβ1−40 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.

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

    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.)

  19. Amyloid β-Protein as a Substrate Interacts with Extracellular Matrix to Promote Neurite Outgrowth

    Koo, Edward H.; Park, Lisa; Selkoe, Dennis J.

    1993-05-01

    Progressive deposition of amyloid β-protein (Aβ) in brain parenchyma and blood vessels is a characteristic feature of Alzheimer disease. Recent evidence suggests that addition of solubilized synthetic Aβ to medium may produce toxic or trophic effects on cultured hippocampal neurons. Because soluble Aβ may not accumulate in significant quantities in brain, we asked whether immobilized Aβ peptide as a substrate alters neurite outgrowth from cultured rat peripheral sensory neurons. This paradigm may closely mimic the conditions in Alzheimer disease brain tissue, in which neurites contact insoluble, extracellular aggregates of β-amyloid. We detected no detrimental effects of Aβ substrate on neurite outgrowth. Rather, Aβ in combination with low doses of laminin or fibronectin enhanced neurite out-growth from these neuronal explants. Our results suggest that insoluble Aβ in the cerebral neuropil may serve as a neurite-promoting matrix, perhaps explaining the apparent regenerative response of neurites observed around amyloid plaques in Alzheimer disease. Moreover, in concert with the recent discovery of Aβ production by cultured neurons, our data suggest that Aβ plays a normal physiological role in brain by complexing with the extracellular matrix.

  20. Subcellular trafficking of the amyloid precursor protein gene family and its pathogenic role in Alzheimer's disease.

    Kins, Stefan; Lauther, Nadine; Szodorai, Anita; Beyreuther, Konrad

    2006-01-01

    Changes in the intracellular transport of amyloid precursor protein (APP) affect the extent to which APP is exposed to alpha- or beta-secretase in a common subcellular compartment and therefore directly influence the degree to which APP undergoes the amyloidogenic pathway leading to generation of beta-amyloid. As the presynaptic regions of neurons are thought to be the main source of beta-amyloid in the brain, attention has been focused on axonal APP trafficking. APP is transported along axons by a fast, kinesin-dependent anterograde transport mechanism. Despite the wealth of in vivo and in vitro data that have accumulated regarding the connection of APP to kinesin transport, it is not yet clear if APP is coupled to its specific motor protein via an intracellular interaction partner, such as the c-Jun N-terminal kinase-interacting protein, or by yet another unknown molecular mechanism. The cargo proteins that form a functional complex with APP are also unknown. Due to the long lifespan, and vast extent, of neurons, in particular axons, neurons are highly sensitive to changes in subcellular transport. Recent in vitro and in vivo studies have shown that variations in APP or tau affect mitochondrial and synaptic vesicle transport. Further, it was shown that this axonal dysfunction might lead to impaired synaptic plasticity, which is crucial for neuronal viability and function. Thus, changes in APP and tau expression may cause perturbed axonal transport and changes in APP processing, contributing to cognitive decline and neurodegeneration in Alzheimer's disease. PMID:17047360

  1. Association of serum leptin with serum C-reactive protein in hemodialysis patients

    Rastegari Ebrahim

    2012-04-01

    Full Text Available Introduction: Recent investigations have shown that leptin is cleared principally by the kidney. Objectives: To examine whether and how in patients on hemodialysis the level of C-reactive protein level correlate with serum leptin. Patients and Methods: The total patients were 36. The mean patients’ age were 46 (16 years. The median length of the time patients were on hemodialysis were 19 months. Results: The mean serum C-reactive protein was 8.7 (6.6 mg/l (median: 8 mg/l. The mean serum leptin was 9.4 (14 ng/ml (median: 5.75 ng/ml. In this study we found a significant inverse correlation of serum leptin with serum C-reactive protein (r= -0.57, p= 0.041 was seen. Conclusion: Our data supports, the positive effect of leptin on nutrition and support the theory of protective effects (reverse epidemiology of leptin in hemodialysis patients.

  2. Lactic acid induces aberrant amyloid precursor protein processing by promoting its interaction with endoplasmic reticulum chaperone proteins.

    Yiwen Xiang

    Full Text Available BACKGROUND: Lactic acid, a natural by-product of glycolysis, is produced at excess levels in response to impaired mitochondrial function, high-energy demand, and low oxygen availability. The enzyme involved in the production of β-amyloid peptide (Aβ of Alzheimer's disease, BACE1, functions optimally at lower pH, which led us to investigate a potential role of lactic acid in the processing of amyloid precursor protein (APP. METHODOLOGY/PRINCIPAL FINDINGS: Lactic acid increased levels of Aβ40 and 42, as measured by ELISA, in culture medium of human neuroblastoma cells (SH-SY5Y, whereas it decreased APP metabolites, such as sAPPα. In cell lysates, APP levels were increased and APP was found to interact with ER-chaperones in a perinuclear region, as determined by co-immunoprecipitation and fluorescence microscopy studies. Lactic acid had only a very modest effect on cellular pH, did increase the levels of ER chaperones Grp78 and Grp94 and led to APP aggregate formation reminiscent of aggresomes. CONCLUSIONS/SIGNIFICANCE: These findings suggest that sustained elevations in lactic acid levels could be a risk factor in amyloidogenesis related to Alzheimer's disease through enhanced APP interaction with ER chaperone proteins and aberrant APP processing leading to increased generation of amyloid peptides and APP aggregates.

  3. An accessory protein required for anchoring and assembly of amyloid fibres in B. subtilis biofilms.

    Romero, Diego; Vlamakis, Hera; Losick, Richard; Kolter, Roberto

    2011-06-01

    Cells within Bacillus subtilis biofilms are held in place by an extracellular matrix that contains cell-anchored amyloid fibres, composed of the amyloidogenic protein TasA. As biofilms age they disassemble because the cells release the amyloid fibres. 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; previously YqxM) that serves both to anchor the fibres to the cell wall and to assemble TasA into fibres. TapA is found in discrete foci in the cell envelope and these foci disappear when cells are treated with a mixture of D-amino acids. Purified cell wall sacculi retain a functional form of this anchoring protein such that purified fibres can be anchored to the sacculi in vitro. In addition, we show that TapA is essential for the proper assembly of the fibres. Its absence results in a dramatic reduction in TasA levels and what little TasA is left produces only thin fibres that are not anchored to the cell. PMID:21477127

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

    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-κB 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-κB (NF-κB). 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. Hepatic expression of serum amyloid A1 is induced by traumatic brain injury and modulated by telmisartan.

    Villapol, Sonia; Kryndushkin, Dmitry; Balarezo, Maria G; Campbell, Ashley M; Saavedra, Juan M; Shewmaker, Frank P; Symes, Aviva J

    2015-10-01

    Traumatic brain injury affects the whole body in addition to the direct impact on the brain. The systemic response to trauma is associated with the hepatic acute-phase response. To further characterize this response, we performed controlled cortical impact injury on male mice and determined the expression of serum amyloid A1 (SAA1), an apolipoprotein, induced at the early stages of the acute-phase response in liver and plasma. After cortical impact injury, induction of SAA1 was detectable in plasma at 6 hours post-injury and in liver at 1 day post-injury, followed by gradual diminution over time. In the liver, cortical impact injury increased neutrophil and macrophage infiltration, apoptosis, and expression of mRNA encoding the chemokines CXCL1 and CXCL10. An increase in angiotensin II AT1 receptor mRNA at 3 days post-injury was also observed. Administration of the AT1 receptor antagonist telmisartan 1 hour post-injury significantly decreased liver SAA1 levels and CXCL10 mRNA expression, but did not affect CXCL1 expression or the number of apoptotic cells or infiltrating leukocytes. To our knowledge, this is the first study to demonstrate that SAA1 is induced in the liver after traumatic brain injury and that telmisartan prevents this response. Elucidating the molecular pathogenesis of the liver after brain injury will assist in understanding the efficacy of therapeutic approaches to brain injury. PMID:26435412

  6. Reexamining Alzheimer's disease: evidence for a protective role for amyloid-beta protein precursor and amyloid-beta.

    Castellani, Rudy J; Lee, Hyoung-gon; Siedlak, Sandra L; Nunomura, Akihiko; Hayashi, Takaaki; Nakamura, Masao; Zhu, Xiongwei; Perry, George; Smith, Mark A

    2009-01-01

    Alzheimer's disease (AD) is an age-related neurodegenerative disease characterized clinically by cognitive decline and pathologically by the accumulation of amyloid-beta-containing senile plaques and neurofibrillary tangles. A great deal of attention has focused, focused on amyloid-beta as the major pathogenic mechanism with the ultimate goal of using amyloid-beta lowering therapies as an avenue of treatment. Unfortunately, nearly a quarter century later, no tangible progress has been offered, whereas spectacular failure tends to be the most compelling. We have long contended, as has substantial literature, that proteinaceous accumulations are simply downstream and, often, endstage manifestations of disease. Their overall poor correlation with the level of dementia, and their presence in the cognitively intact is evidence that is often ignored as an inconvenient truth. Current research examining amyloid oligomers, therefore, will add copious details to what is, in essence, a reductionist distraction from upstream pleiotrophic processes such as oxidative stress, cell cycle dysfunction, and inflammation. It is now long overdue that the neuroscientists avoid the pitfall of perseverating on "proteinopathies'' and recognize that the continued targeting of end stage lesions in the face of repeated failure, or worse, is a losing proposition. PMID:19584435

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

    Yan, Y C; Bai, Y.(Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China); Wang, L.F.; Miao, S Y; Koide, S S

    1990-01-01

    A rat testis lambda gt11 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 r...

  8. Inhibition of beta-site amyloid precursor protein-cleaving enzyme and beta-amyloid precursor protein genes in SK-N-SH cells

    Suqin Gao; Lin Sun; Enji Han; Hongshun Qi; Jinbo Feng; Shunliang Xu; Wen Xia

    2009-01-01

    BACKGROUND:Previous studies have demonstrated that Piper futokadsura stem selectively inhibits expression of amyloid precursor protein (APP) at the mRNA level.In addition,the piperlonguminine (A) and dihydropiperlonguminine (B) components (1:0.8),which can be separated from Futokadsura stem,selectively inhibit expression of the APP at mRNA and protein levels.OBJECTIVE:Based on previous findings,the present study investigated the effects of β-site amyloid precursor protein cleaving enzyme (BACE1) and APP genes on the production of β-amyloid peptide 42 (Aβ42) in human neuroblastoma cells (SK-N-SH cells) using small interfering RNAs (siRNAs) and A/B components separated from Futokadsura stem,respectively.DESIGN,TIME AND SETTING:A gene interference-based randomized,controlled,in vitro experiment was performed at the Key Laboratory of Cardiovascular Remodeling and Function Research,Ministries of Education and Public Health,and Institute of Pharmacologic Research,School of Pharmaceutical Science & Department of Biochemistry,School of Medicine,Shandong University between July 2006 and December 2007.MATERIALS:SK-N-SH cells were provided by Shanghai Institutes of Biological Sciences,Chinese Academy of Sciences,Shanghai,China;mouse anti-human BACE1 monoclonal antibody was purchased from R&D Systems,USA;mouse anti-human APP monoclonal antibody was purchased from Cell Signaling Technology,USA;and horseradish peroxidase (HRP)-conjugated goat anti-mouse IgG was provided by Sigma,USA.METHODS:The human BACE1 cDNA sequence was obtained from NCBI website (www.ncbi.nlm.nih.gov/sites/entrez).Three pairs of siRNAs,specific to human BACE1 gene,were synthesized through the use of Silencer? pre-designed siRNA specification,and were transfected into SK-N-SH cells with siPORT NeoFX transfection agent to compare the effects of different concentrations of siRNAs (10-50 nmol/L) on SK-N-SH cells.Futokadsura stem was separated and purified with chemical methods,and the crystal was composed of

  9. Serum amyloid P component-DNA complexes are decreased in systemic lupus erythematosus. inverse association with anti-dsDNA antibodies

    Voss, Anne; Nielsen, Ellen Holm; Svehag, Sven Erik;

    2008-01-01

    served as controls. RESULTS: SLE patients had normal serum concentrations of SAP, whereas SAP-DNA complexes were decreased. Two-thirds of the SLE patients tested persistently SAP-DNA complex-negative. There was no relationship between the occurrence of SAP-DNA complexes and clinical manifestations. SAP-DNA......OBJECTIVE: To study serum levels of serum amyloid P component (SAP) and SAP-DNA complexes in a population-based cohort of patients with systemic lupus erythematosus (SLE). METHODS: The study population comprised 82 unselected patients of predominantly Scandinavian ancestry with SLE according to...... current classification criteria. Serum samples were collected at baseline and serially for up to 2 years. SAP component and SAP-DNA complexes were measured by ELISA. Associations between SAP-DNA and clinical manifestations or serological findings were analyzed. Ninety healthy, age-matched blood donors...

  10. Association of serum leptin with serum C-reactive protein in hemodialysis patients

    Rastegari Ebrahim; Nasri Hamid

    2012-01-01

    Introduction: Recent investigations have shown that leptin is cleared principally by the kidney. Objectives: To examine whether and how in patients on hemodialysis the level of C-reactive protein level correlate with serum leptin. Patients and Methods: The total patients were 36. The mean patients’ age were 46 (16) years. The median length of the time patients were on hemodialysis were 19 months. Results: The mean serum C-reactive protein was 8.7 (6.6) mg/l (median:...

  11. Evaluation of the systemic acute phase response and endometrial gene expression of serum amyloid A and pro- and anti-inflammatory cytokines in mares with experimentally induced endometritis.

    Christoffersen, Mette; Mette, Christoffersen; Baagoe, Camilla Dooleweerdt; Camilla Dooleweerdt, Baagoe; Jacobsen, Stine; Stine, Jacobsen; Bojesen, Anders Miki; Anders Miki, Bojesen; Petersen, Morten Roenn; Morten Roenn, Petersen; Lehn-Jensen, Henrik; Henrik, Lehn-Jensen

    2010-11-15

    Infectious infertility in the mare is clinically well described, little is however known about the systemic acute phase reaction (APR) and local immunological responses accompanying equine endometritis. The aim of this study was to monitor selected markers of the APR in the systemic circulation and to correlate them to the local innate immune response in the uterus during infectious endometritis. Six adult standard bred mares received an intrauterine infusion of 10(9)CFU Escherichia coli. Blood samples were obtained before (0 h) and 3, 6, 12, 24, 36, 48, 72, 96 and 120 h post inoculation (pi), and endometrial biopsies were sampled before, and 3, 12, 24, 48 and 72 h pi. The infectious endometritis elicited a systemic APR with significantly increased concentrations of the acute phase proteins (APPs) serum amyloid A (SAA) and fibrinogen. Relative gene expression analyses were performed on extracted RNA from endometrial biopsies using quantitative real-time PCR and specific primers for SAA and pro- and anti-inflammatory cytokines. Expression of SAA was significantly up-regulated at 3 and 12h pi, and a significant up-regulated expression of IL-1β, TNFα, IL-8 and IL-10 was observed at 3h pi. Plasma concentration of SAA was significantly correlated to endometrial SAA expression. The results of the present study demonstrate that endometritis gives rise to a systemic APR and an up-regulated endometrial gene expression of SAA and several pro-and anti-inflammatory cytokines. Understanding endometrial expression of acute phase proteins and selected cytokines contributing to uterine immunity in equine endometritis could improve understanding of events leading to infertility in the mare and help identify candidate genes of mediators/markers for diagnostic use. PMID:20728224

  12. Measurement of acute phase proteins for assessing severity of Plasmodium falciparum malaria.

    Gillespie, S H; C. DOW; Raynes, J G; Behrens, R. H.; Chiodini, P L; McAdam, K P

    1991-01-01

    Seventeen adult patients with acute Plasmodium falciparum malaria, admitted to the Hospital for Tropical Diseases, were studied. Serial measurements of the serum concentration of C-reactive protein, serum amyloid A protein, and percentage parasitaemia were determined, together with initial measurement of serum electrolytes, liver function, haemoglobin, white cell and platelet counts. Initial C-reactive protein and serum amyloid A concentrations were increased (C-reactive protein mean 49.0 mg/...

  13. Serum paraoxonase activity and protein thiols in patients with hyperlipidemia

    Mungli Prakash; Jeevan K Shetty; Sudeshna Tripathy; Pannuri Vikram; Manish Verma

    2009-01-01

    Objective: In the present study we evaluated the paraoxonase activity and protein thiols level in south Indian population with newly diagnosed hyperlipidemia. Methods: The study was conducted on 55 newly diagnosed hyperlipidemic pa-tients and 57 healthy controls. Serum paraoxonase activity and protein thiols were estimated by spectrophotometeric method and lipid profile by enzymatic kinetic assay method. Results: Serum paraoxonase activity, protein thiols and high density lipoprotein levels were low and total cholesterol, triglycerides and low density lipoprutein levels were high in patients with hyperlipidemia compared to healthy controls ( P < 0.01 ). Serum paranxonase activity correlated positively with protein thiols and high density lipoprotein (P<0.01). Conclusion: Decreased paraoxonase activity and protein thiols were found in patients with hyperlipi-demia. This may indicate the susceptibility of this population to accelerated atherogenesis and protein oxidation.

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

    Natalia N Nalivaeva

    2014-09-01

    Full Text Available Abnormal elevation of amyloid β-peptide (Aβ levels in the brain is the primary trigger for neuronal cell death specific to Alzheimer’s disease (AD. It is now evident that Aβ 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 Aβ 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.

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

    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 Aβ 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 Aβ 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 Aβ production.

  16. Amyloid Properties of Asparagine and Glutamine in Prion-like Proteins.

    Zhang, Yuan; Man, Viet Hoang; Roland, Christopher; Sagui, Celeste

    2016-05-18

    Sequences rich in glutamine (Q) and asparagine (N) are intrinsically disordered in monomeric form, but can aggregate into highly ordered amyloids, as seen in Q/N-rich prion domains (PrDs). Amyloids are fibrillar protein aggregates rich in β-sheet structures that can self-propagate through protein-conformational chain reactions. Here, we present a comprehensive theoretical study of N/Q-rich peptides, including sequences found in the yeast Sup35 PrD, in parallel and antiparallel β-sheet aggregates, and probe via fully atomistic molecular dynamics simulations all their possible steric-zipper interfaces in order to determine their protofibril structure and their relative stability. Our results show that polyglutamine aggregates are more stable than polyasparagine aggregates. Enthalpic contributions to the free energy favor the formation of polyQ protofibrils, while entropic contributions favor the formation of polyN protofibrils. The considerably larger phase space that disordered polyQ must sample on its way to aggregation probably is at the root of the associated slower kinetics observed experimentally. When other amino acids are present, such as in the Sup35 PrD, their shorter side chains favor steric-zipper formation for N but not Q, as they preclude the in-register association of the long Q side chains. PMID:26911543

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

    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 Aβ 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 Aβ 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 Aβ production

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

    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. First identification of resident and circulating fibrocytes in Dupuytren's disease shown to be inhibited by serum amyloid P and Xiapex.

    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

  20. Structural and dynamic study of the transmembrane domain of the amyloid precursor protein.

    Nadezhdin, K D; Bocharova, O V; Bocharov, E V; Arseniev, A S

    2011-01-01

    Alzheimer's disease affects people all over the world, regardless of nationality, gender or social status. An adequate study of the disease requires essential understanding of the molecular fundamentals of the pathogenesis. The amyloid β-peptide, which forms amyloid plaques in the brain of people with Alzheimer's disease, is the product of sequential cleavage of a single-span membrane amyloid precursor protein (APP). More than half of the APP mutations found to be associated with familial forms of Alzheimer's disease are located in its transmembrane domain. The pathogenic mutations presumably affect the structural-dynamic properties of the APP transmembrane domain by changing its conformational stability and/or lateral dimerization. In the present study, the structure and dynamics of the recombinant peptide corresponding to the APP fragment, Gln686-Lys726, which comprises the APP transmembrane domain with an adjacent N-terminal juxtamembrane sequence, were determined in the membrane mimetic environment composed of detergent micelles using NMR spectroscopy. The structure obtained in dodecylphosphocholine micelles consists of two α-helices: a short surface-associated juxtamembrane helix (Lys687-Asp694) and a long transmembrane helix (Gly700-Leu723), both connected via a mobile loop region. A minor bend of the transmembrane α-helix is observed near the paired residues Gly708-Gly709. A cholesterol-binding hydrophobic cavity is apparently formed under the loop region, where the juxtamembrane α-helix comes into contact with the membrane surface near the N-terminus of the transmembrane α-helix. PMID:22649674

  1. Interaction of Serum Proteins with Surface of Hemodialysis Fiber Membranes

    Afrin, Rehana; Shirako, Yuji; Kishimoto, Kikuo; Ikai, Atsushi

    2012-08-01

    The poly(vinyl pyrrolidone)-covered hydrophilic surface of hollow-fiber membranes (fiber membrane, hereafter) for hemodialysis was mechanically probed using modified tips on an atomic force microscope (AFM) with covalent crosslinkers and several types of serum protein. The retraction part of many of the force extension (F-E) curves obtained with AFM tips coated with serum albumin had a long and smooth extension up to 200-300 nm indicating forced elongation of poly(vinyl pyrrolidone) chains. When fibrinogen-coated tips were used, long extension F-E curves up to 500 nm with multiple peaks were obtained in addition to smooth curves most likely reflecting the unfolding of fibrinogen molecules. The results indicated that individual polymer chains had a significant affinity toward serum proteins. The adhesion frequency of tips coated with serum proteins was lower on the poly(vinyl pyrrolidone) surface than on the uncoated hydrophobic polysulfone surface.

  2. Development of new fusion proteins for visualizing amyloid-β oligomers in vivo.

    Ochiishi, Tomoyo; Doi, Motomichi; Yamasaki, Kazuhiko; Hirose, Keiko; Kitamura, Akira; Urabe, Takao; Hattori, Nobutaka; Kinjo, Masataka; Ebihara, Tatsuhiko; Shimura, Hideki

    2016-01-01

    The intracellular accumulation of amyloid-β (Aβ) oligomers critically contributes to disease progression in Alzheimer's disease (AD) and can be the potential target of AD therapy. Direct observation of molecular dynamics of Aβ oligomers in vivo is key for drug discovery research, however, it has been challenging because Aβ aggregation inhibits the fluorescence from fusion proteins. Here, we developed Aβ1-42-GFP fusion proteins that are oligomerized and visualize their dynamics inside cells even when aggregated. We examined the aggregation states of Aβ-GFP fusion proteins using several methods and confirmed that they did not assemble into fibrils, but instead formed oligomers in vitro and in live cells. By arranging the length of the liker between Aβ and GFP, we generated two fusion proteins with "a long-linker" and "a short-linker", and revealed that the aggregation property of fusion proteins can be evaluated by measuring fluorescence intensities using rat primary culture neurons transfected with Aβ-GFP plasmids and Aβ-GFP transgenic C. elegans. We found that Aβ-GFP fusion proteins induced cell death in COS7 cells. These results suggested that novel Aβ-GFP fusion proteins could be utilized for studying the physiological functions of Aβ oligomers in living cells and animals, and for drug screening by analyzing Aβ toxicity. PMID:26982553

  3. Development of new fusion proteins for visualizing amyloid-β oligomers in vivo

    Ochiishi, Tomoyo; Doi, Motomichi; Yamasaki, Kazuhiko; Hirose, Keiko; Kitamura, Akira; Urabe, Takao; Hattori, Nobutaka; Kinjo, Masataka; Ebihara, Tatsuhiko; Shimura, Hideki

    2016-01-01

    The intracellular accumulation of amyloid-β (Aβ) oligomers critically contributes to disease progression in Alzheimer’s disease (AD) and can be the potential target of AD therapy. Direct observation of molecular dynamics of Aβ oligomers in vivo is key for drug discovery research, however, it has been challenging because Aβ aggregation inhibits the fluorescence from fusion proteins. Here, we developed Aβ1-42-GFP fusion proteins that are oligomerized and visualize their dynamics inside cells even when aggregated. We examined the aggregation states of Aβ-GFP fusion proteins using several methods and confirmed that they did not assemble into fibrils, but instead formed oligomers in vitro and in live cells. By arranging the length of the liker between Aβ and GFP, we generated two fusion proteins with “a long-linker” and “a short-linker”, and revealed that the aggregation property of fusion proteins can be evaluated by measuring fluorescence intensities using rat primary culture neurons transfected with Aβ-GFP plasmids and Aβ-GFP transgenic C. elegans. We found that Aβ-GFP fusion proteins induced cell death in COS7 cells. These results suggested that novel Aβ-GFP fusion proteins could be utilized for studying the physiological functions of Aβ oligomers in living cells and animals, and for drug screening by analyzing Aβ toxicity. PMID:26982553

  4. Erythropoietin binding protein from mammalian serum

    Clemons, G.K.

    1997-04-29

    Purified mammalian erythropoietin binding-protein is disclosed, and its isolation, identification, characterization, purification, and immunoassay are described. The erythropoietin binding protein can be used for regulation of erythropoiesis by regulating levels and half-life of erythropoietin. A diagnostic kit for determination of level of erythropoietin binding protein is also described. 11 figs.

  5. Erythropoietin binding protein from mammalian serum

    Clemons, Gisela K. (Berkeley, CA)

    1997-01-01

    Purified mammalian erythropoietin binding-protein is disclosed, and its isolation, identification, characterization, purification, and immunoassay are described. The erythropoietin binding protein can be used for regulation of erythropoiesis by regulating levels and half-life of erythropoietin. A diagnostic kit for determination of level of erythropoietin binding protein is also described.

  6. The Psen1-L166P-knock-in mutation leads to amyloid deposition in human wild-type amyloid precursor protein YAC transgenic mice

    Vidal, Ruben; Sammeta, Neeraja; Garringer, Holly J.; Sambamurti, Kumar; Miravalle, Leticia; Lamb, Bruce T.; Ghetti, Bernardino

    2012-01-01

    Genetically engineered mice have been generated to model cerebral β-amyloidosis, one of the hallmarks of Alzheimer disease (AD) pathology, based on the overexpression of a mutated cDNA of the amyloid-β precursor protein (AβPP) or by knock-in of the murine Aβpp gene alone or with presenilin1 mutations. Here we describe the generation and initial characterization of a new mouse line based on the presence of 2 copies of the human genomic region encoding the wild-type AβPP and the L166P presenili...

  7. Amyloid precursor protein expression and processing are differentially regulated during cortical neuron differentiation

    Bergström, Petra; Agholme, Lotta; Nazir, Faisal Hayat; Satir, Tugce Munise; Toombs, Jamie; Wellington, Henrietta; Strandberg, Joakim; Bontell, Thomas Olsson; Kvartsberg, Hlin; Holmström, Maria; Boreström, Cecilia; Simonsson, Stina; Kunath, Tilo; Lindahl, Anders; Blennow, Kaj; Hanse, Eric; Portelius, Erik; Wray, Selina; Zetterberg, Henrik

    2016-01-01

    Amyloid precursor protein (APP) and its cleavage product amyloid β (Aβ) have been thoroughly studied in Alzheimer’s disease. However, APP also appears to be important for neuronal development. Differentiation of induced pluripotent stem cells (iPSCs) towards cortical neurons enables in vitro mechanistic studies on human neuronal development. Here, we investigated expression and proteolytic processing of APP during differentiation of human iPSCs towards cortical neurons over a 100-day period. APP expression remained stable during neuronal differentiation, whereas APP processing changed. α-Cleaved soluble APP (sAPPα) was secreted early during differentiation, from neuronal progenitors, while β-cleaved soluble APP (sAPPβ) was first secreted after deep-layer neurons had formed. Short Aβ peptides, including Aβ1-15/16, peaked during the progenitor stage, while processing shifted towards longer peptides, such as Aβ1-40/42, when post-mitotic neurons appeared. This indicates that APP processing is regulated throughout differentiation of cortical neurons and that amyloidogenic APP processing, as reflected by Aβ1-40/42, is associated with mature neuronal phenotypes. PMID:27383650

  8. Dual roles of the transmembrane protein p23/TMP21 in the modulation of amyloid precursor protein metabolism

    Wieland Felix T

    2007-02-01

    Full Text Available Abstract Background Alzheimer's disease (AD is characterized by cerebral deposition of β-amyloid (Aβ peptides. Aβ is released from ectodomain cleaved amyloid precursor protein (APP via intramembranous proteolysis by γ-secretase, a complex consisting of presenilin and a few other proteins. p23/TMP21, a member of the p24 family type I transmembrane proteins, was recently identified as a presenilin complex component capable of modulating γ-secretase cleavage. The p24 family proteins form oligomeric complexes and regulate vesicular trafficking in the early secretory pathway, but their role in APP trafficking has not been investigated. Results Here, we report that siRNA-mediated depletion of p23 in N2a neuroblastoma and HeLa cells produces concomitant knockdown of additional p24 family proteins and increases secretion of sAPP. Furthermore, intact cell and cell-free Aβ production increases following p23 knockdown, similar to data reported earlier using HEK293 cells. However, we find that p23 is not present in mature γ-secretase complexes isolated using an active-site γ-secretase inhibitor. Depletion of p23 and expression of a familial AD-linked PS1 mutant have additive effects on Aβ42 production. Knockdown of p23 expression confers biosynthetic stability to nascent APP, allowing its efficient maturation and surface accumulation. Moreover, immunoisolation analyses show decrease in co-residence of APP and the APP adaptor Mint3. Thus, multiple lines of evidence indicate that p23 function influences APP trafficking and sAPP release independent of its reported role in γ-secretase modulation. Conclusion These data assign significance to p24 family proteins in regulating APP trafficking in the continuum of bidirectional transport between the ER and Golgi, and ascribe new relevance to the regulation of early trafficking in AD pathogenesis.

  9. Amyloid beta protein and tau in cerebrospinal fluid and plasma as biomarkers for dementia: a review of recent literature.

    Frankfort, S.V.; Tulner, L.R.; Campen, J.P. van; Verbeek, M.M.; Jansen, R.W.; Beijnen, J.H.

    2008-01-01

    This review addresses recent developments in amyloid beta (Abeta), total tau (t-tau), and phosporylated tau (p-tau) protein analysis, in cerebrospinal fluid (CSF) and plasma as biomarkers for dementia. Recent research focused on the protection of patients with mild cognitive impairment (MCI) into de

  10. Protein τ-mediated effects on rat hippocampal choline transporters CHT1 and τ-amyloid β interactions

    Krištofíková, Z.; Řípová, D.; Hegnerová, Kateřina; Šírová, J.; Homola, Jiří

    2013-01-01

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

  11. The coding sequence of amyloid-beta precursor protein APP contains a neural-specific promoter element.

    Collin, R.W.J.; Martens, G.J.M.

    2006-01-01

    The amyloid-beta precursor protein APP is generally accepted to be involved in the pathology of Alzheimer's disease. Since its physiological role is still unclear, we decided to study the function of APP via stable transgenesis in the amphibian Xenopus laevis. However, the application of constructs

  12. 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

    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.

  13. 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.

    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

  14. The intramembrane cleavage site of the amyloid precursor protein depends on the length of its transmembrane domain

    Lichtenthaler, Stefan F.; Beher, Dirk; Heike S Grimm; Wang, Rong; Shearman, Mark S.; Masters, Colin L.; Beyreuther, Konrad

    2002-01-01

    Proteolytic processing of the amyloid precursor protein by β-secretase generates C99, which subsequently is cleaved by γ-secretase, yielding the amyloid β peptide (Aβ). This γ-cleavage occurs within the transmembrane domain (TMD) of C99 and is similar to the intramembrane cleavage of Notch. However, Notch and C99 differ in their site of intramembrane cleavage. The main γ-cleavage of C99 occurs in the middle of the TMD, whereas the cleavage of Notch occurs close to the C-terminal end of the TM...

  15. The amyloid precursor protein – a novel player within the molecular array of presynaptic nanomachines

    Melanie Lassek

    2016-01-01

    Full Text Available More than 20 years ago the amyloid precursor protein (APP was identified as the precursor protein of the Aβ peptide, the main component of senile plaques in brains affected by Alzheimer´s disease. The pathophysiology of AD, characterized by a massive loss of synapses, cognitive decline, and behavioral changes was in principle attributed to the accumulation of Aβ. Within the last decades, much effort has gone into understanding the molecular basis of the progression of Alzheimer´s disease. However, little is known about the actual physiological function of amyloid precursor proteins. Allocating APP to the proteome of the structurally and functionally dynamic presynaptic active zone highlights APP as a hitherto unknown player within the setting of the presynapse. The molecular array of presynaptic nanomachines comprising the life cycle of synaptic vesicles, exo- and endocytosis, cytoskeletal rearrangements, and mitochondrial activity provides a balance between structural and functional maintenance and diversity. The generation of genetically designed mouse models further deciphered APP as an essential player in synapse formation and plasticity. Deletion of APP causes an age-dependent phenotype: while younger mice revealed almost no physiological impairments, this condition was changed in the elderly mice. Interestingly, the proteomic composition of neurotransmitter release sites already revealed substantial changes at young age. These changes point to a network that incorporates APP into a cluster of nanomachines. Currently, the underlying mechanism of how APP acts within these machines is still elusive. Within the scope of this review, we shall construct a network of APP interaction partners within the presynaptic active zone. Furthermore, we intend to outline how deletion of APP affects this network during space and time leading to impairments in learning and memory. These alterations may provide a molecular link to the pathogenesis of

  16. Differential Associations of Serum Amyloid A and Pentraxin-3 with Allele-Specific Lipoprotein(a) Levels in African Americans and Caucasians

    Enkhmaa, Byambaa; Anuurad, Erdembileg; Ozturk, Zeynep; ZHANG Wei; Pearson, Thomas A.; Berglund, Lars

    2011-01-01

    Lipoprotein(a) [Lp(a)] is a CVD risk factor, where inflammation impacts levels differentially across ethnicity. We investigated the effect of systemic [serum amyloid A (SAA)] and vascular [pentraxin-3 (PTX-3)] inflammation on Lp(a) levels across different apo(a) sizes in a bi-ethnic population. Lp(a) and allele-specific apo(a) levels, apo(a) sizes, SAA and PTX-3 levels were determined in 336 Caucasians and 224 African Americans. We dichotomized subjects into 2 groups using the respective medi...

  17. Post-exercise dynamics of serum amyloid A blood concentration in thoroughbred horses classified as injured and non-injured after the race.

    Turlo, A; Cywinska, A; Czopowicz, M; Witkowski, L; Szarska, E; Winnicka, A

    2015-06-01

    The aim of this study was to evaluate serum amyloid A (SAA) concentration in horses with orthopedic injuries acquired during racing and in healthy ones after completing the race. Injuries of bone and tendon did not cause radical increase in SAA concentration observed in other inflammatory conditions. SAA concentration correlated positively with white blood cell count (WBC) on the 3rd-4th days after race being significantly higher in the injured horses than in the control group in that time. It was suggested that racing effort may cause increase in SAA level, more pronounced in horses manifesting clinical signs of orthopedic injury after the race. PMID:25933933

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

    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)

  19. Levels of alpha- and beta-secretase cleaved amyloid precursor protein in the cerebrospinal fluid of Alzheimer's disease patients

    Sennvik, K; Fastbom, J; Blomberg, M;

    2000-01-01

    Alternative cleavage of the amyloid precursor protein (APP) results in generation and secretion of both soluble APP (sAPP) and beta-amyloid (Abeta). Abeta is the main component of the amyloid depositions in the brains of Alzheimer's disease (AD) patients. Using Western blotting, we compared the...... levels of alpha-secretase cleaved sAPP, beta-secretase cleaved sAPP and total sAPP, in cerebrospinal fluid (CSF) from 13 sporadic AD patients and 13 healthy controls. Our findings show significant amounts of beta-secretase cleaved sAPP in CSF. There was no statistically significant difference in the...... levels of beta-secretase cleaved sAPP between AD patients and controls. The levels of alpha-secretase cleaved sAPP and total sAPP were, however, found to be significantly lower in the AD patients than in the controls....

  20. High-density lipoprotein associated factors apoA-I and serum amyloid A in Chinese non-diabetic patients with coronary heart disease

    CHEN Guo-liang; LIU Li-wei; XIE Shuang; LIU Hong; LIU Yu-qing; LI Yi-shi

    2010-01-01

    Background High-density lipoprotein cholesterol(HDL-C)levels are a strong,independent inverse predictor of coronary heart disease (CHD).In this cross-sectional study we investigated the interrelationships between HDL-C and HDL relaled factors apolipoprotein A-I(apoA-I)and serum amyloid A(SAA)and the presence and extent of CHD in a population of Chinese patients with CHD. Methods Two hundred and twenty-four consecutive patients took part in this study.Demographic data were obtained from hospital records.Serum chemical concentrations were measured by standard laboratory methods.Reaults The concentrations of high-sensitive C-reactive protein(hsCRP)(median:1.85 mg/L)and SAP,(median:9.40 mg/L)were significantly higher in the CHD group(P<0.05),while concentrations of HDL-C(0.03±0.25)mmol/L)and apoA-I((604.59±1 05.79)mmol/L)were significantly lower than those in the non-CHD group(P<0.05).The concentrations of apoA-l decreased with the increase in vascular damage.but the difference did not reach statistical significance.However, the concentrations of hsCRP and SAA increased with the increase in vascular damage.The unadjusted odd ratios(ORs)(CI) for apoA-I and SAA of the presence of CHD were 0.093(0.990-0.997)(P=0.00)and 2.571(1.029-6.424)(P<0.05),respectively.The association between elevated SAA and the presence of CHD was lost after adjusting for lipid status parameter concentrations.The associations between apoA-I.SAA and the extent of CHD remained strong,regardless of confounding variables.Conclusions Increased concentrations of SAA represent the inflammatory marker of the extent of coronary stenosis in patients with CHD.In contrast to SAA, the level of apoA-I was also associated with the presence of CHD, indicating that apoA-I was not only a marker of CHD presence but also a quantitative indicator of CHD extent.In short.determining the change apolipoprotein content within HDL particle is a more accurate and effective method to evaluate the impact of HDL on CHD.

  1. Serum Copper and Plasma Protein Status in Normal Pregnancy

    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.

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

    2008-01-01

    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 undersyanding 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 H.CC and cirrhosis or chronic hepatitis B were found. RESULTS: One hundred and twenty-eight serum protein peaks between.2000 and 30000Da were identified under the condition of signal-to-noise>5 and minimum threshold for cluster>20%.Eight-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 30downregulated 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

  3. Minocycline alleviates beta-amyloid protein and tau pathology via restraining neuroinflammation induced by diabetic metabolic disorder

    Cai, Zhiyou; Yan, Yong; Wang, Yonglong

    2013-01-01

    Background Compelling evidence has shown that diabetic metabolic disorder plays a critical role in the pathogenesis of Alzheimer’s disease, including increased expression of β-amyloid protein (Aβ) and tau protein. Evidence has supported that minocycline, a tetracycline derivative, protects against neuroinflammation induced by neurodegenerative disorders or cerebral ischemia. This study has evaluated minocycline influence on expression of Aβ protein, tau phosphorylation, and inflammatory cytokines (interleukin-1β and tumor necrosis factor-α) in the brain of diabetic rats to clarify neuroprotection by minocycline under diabetic metabolic disorder. Method An animal model of diabetes was established by high fat diet and intraperitoneal injection of streptozocin. In this study, we investigated the effect of minocycline on expression of Aβ protein, tau phosphorylation, and inflammatory cytokines (interleukin-1β and tumor necrosis factor-α) in the hippocampus of diabetic rats via immunohistochemistry, western blotting, and enzyme-linked immunosorbent assay. Results These results showed that minocycline decreased expression of Aβ protein and lowered the phosphorylation of tau protein, and retarded the proinflammatory cytokines, but not amyloid precursor protein. Conclusion On the basis of the finding that minocycline had no influence on amyloid precursor protein and beta-site amyloid precursor protein cleaving enzyme 1 which determines the speed of Aβ generation, the decreases in Aβ production and tau hyperphosphorylation by minocycline are through inhibiting neuroinflammation, which contributes to Aβ production and tau hyperphosphorylation. Minocycline may also lower the self-perpetuating cycle between neuroinflammation and the pathogenesis of tau and Aβ to act as a neuroprotector. Therefore, the ability of minocycline to modulate inflammatory reactions may be of great importance in the selection of neuroprotective agents, especially in chronic conditions

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

    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.

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

    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

  6. Independent relationship between amyloid precursor protein (APP dimerization and γ-secretase processivity.

    Joo In Jung

    Full Text Available Altered production of β-amyloid (Aβ from the amyloid precursor protein (APP is closely associated with Alzheimer's disease (AD. APP has a number of homo- and hetero-dimerizing domains, and studies have suggested that dimerization of β-secretase derived APP carboxyl terminal fragment (CTFβ, C99 impairs processive cleavage by γ-secretase increasing production of long Aβs (e.g., Aβ1-42, 43. Other studies report that APP CTFβ dimers are not γ-secretase substrates. We revisited this issue due to observations made with an artificial APP mutant referred to as 3xK-APP, which contains three lysine residues at the border of the APP ectodomain and transmembrane domain (TMD. This mutant, which dramatically increases production of long Aβ, was found to form SDS-stable APP dimers, once again suggesting a mechanistic link between dimerization and increased production of long Aβ. To further evaluate how multimerization of substrate affects both initial γ-secretase cleavage and subsequent processivity, we generated recombinant wild type- (WT and 3xK-C100 substrates, isolated monomeric, dimeric and trimeric forms of these proteins, and evaluated both ε-cleavage site utilization and Aβ production. These show that multimerization significantly impedes γ-secretase cleavage, irrespective of substrate sequence. Further, the monomeric form of the 3xK-C100 mutant increased long Aβ production without altering the initial ε-cleavage utilization. These data confirm and extend previous studies showing that dimeric substrates are not efficient γ-secretase substrates, and demonstrate that primary sequence determinants within APP substrate alter γ-secretase processivity.

  7. Smoking and serum proteins in atomic bomb survivors in Hiroshima

    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 who participated in the 1979-81 period of the Adult Health Study, an on-going health follow-up program of the RERF. Smoking was strongly related to serum protein concentration after correction for age, sex, and body mass index. Among current smokers as compared to nonsmokers, levels of total protein, β globulin, and γ globulin were significantly lower (p1 and α2 globulin were significantly higher (p1 globulin. Duration of smoking (years) was related to increased α1 and α2 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. Its inclusion in the regression models did not noticeably affect the association between smoking and serum proteins. (author)

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

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

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

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

    2014-01-01

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

  10. Serum protein inhibition of thyrotropin binding to human thyroid tissue

    We used a modificaton of the TSH radioreceptor assay to detect TSH-binding inhibition (TBI) activity in serum and serum fractions from normal subjects and patients with Graves' disease. TBI activity is present in normal IgG prepared by DEAE-Sephadex chromatography and in normal globulins prepared by precipitation at 1.6 M ammonium sulfate. Other normal serum proteins also had TBI activity when large concentrations were tested. Gel filtration chromatography and powder block electrophoresis were used to prepare fractions of normal and Graves' disease sera. In these fractions from normal serum, TBI activity was found in both γ-globulin and α-globulin-albumin fractions electrophoretically and in both 7S and 4S peaks from gel filtration. TBI activity from Graves' disease patients' sera was similarly distributed, but relatively more TBI accompanied the electrophoretic γ-globulins. Sepharose Protein-A and anti-IgG were used as immunoabsorbents to isolate and purify IgG from normal and Graves' disease sera. TBI activity in IgG was proportional to the IgG concentration, indicating that the TBI which migrates as a γ-globulin electrophoretically is an IgG and thus may possibly be an antibody. Inhibitory activity found in normal serum globulins and in the non-IgG fractions of both normal and abnormal sera seriously interferes with attempts to use the TSH radioreceptor assay to study the hypothesized anti-TSH receptor antibody in the serum of patients with Graves' disease