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1.
J Neurol ; 263(8): 1565-74, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27230855

RESUMO

To date, pharmacological treatment options for progressive supranuclear palsy (PSP), a neurodegenerative tauopathy, are limited. The MAO-B inhibitor rasagiline has shown neuroprotective effects in preclinical models of neurodegeneration. To evaluate the safety, tolerability and therapeutic effect of rasagiline on symptom progression in PSP. In this 1-year randomized, double-blind, placebo-controlled trial, 44 patients fulfilling the NINDS-PSP criteria were randomized to 1 mg/d rasagiline or placebo. The combined primary endpoint included symptom progression as measured by the PSP rating scale (PSP-RS) and the requirement of L-dopa rescue medication. Secondary endpoints included Schwab and England Activities of Daily Living (SEADL), Montgomery-Åsberg Depression Rating Scale, Mini Mental State Examination, Frontal Assessment Battery and posturographic measurements. Of the 44 patients randomized, 26 completed the trial per protocol. Rasagiline was well tolerated, with a slight increase of known side effects (hallucinations, ventricular extrasystoles). No effect on the primary endpoint (p = 0.496) was detected. Symptom progression averaged at 11.2 (rasagiline) and 10.8 (placebo) points per year (ΔPSP-RS). No difference was seen in SEADL, depression, cognitive function, frontal executive function and posturographic measurements. Post hoc analyses of PSP-RS subdomains indicate a potential beneficial effect in the "limb motor" subdomain, whereas performance appeared lower in the "mentation" and "history" subdomains in the treatment group. While rasagiline is well tolerated in PSP, a beneficial effect on overall symptom progression was not detected. Post hoc analyses suggest the implementation of more specific endpoints in future studies.


Assuntos
Indanos/uso terapêutico , Inibidores da Monoaminoxidase/uso terapêutico , Paralisia Supranuclear Progressiva/tratamento farmacológico , Idoso , Área Sob a Curva , Transtornos Cognitivos , Depressão/etiologia , Progressão da Doença , Método Duplo-Cego , Eletrocardiografia , Função Executiva/efeitos dos fármacos , Feminino , Seguimentos , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Equilíbrio Postural/efeitos dos fármacos , Transtornos de Sensação/tratamento farmacológico , Transtornos de Sensação/etiologia , Paralisia Supranuclear Progressiva/complicações
2.
J Allergy Clin Immunol ; 134(6): 1271-1279.e10, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25042744

RESUMO

BACKGROUND: Schistosomiasis, a chronic helminth infection, elicits distinct immune responses within the host, ranging from an initial TH1 and subsequent TH2 phase to a regulatory state, and is associated with dampened allergic reactions within the host. OBJECTIVE: We sought to evaluate whether non-transplacental helminth infection during pregnancy alters the offspring's susceptibility to allergy. METHODS: Ovalbumin-induced allergic airway inflammation was analyzed in offspring from Schistosoma mansoni-infected mothers mated during the TH1, TH2, or regulatory phase of infection. Embryos derived from in vitro fertilized oocytes of acutely infected females were transferred into uninfected foster mice to determine the role of placental environment. The fetomaternal unit was further characterized by helminth-specific immune responses and microarray analyses. Eventually, IFN-γ-deficient mice were infected to evaluate the role of this predominant cytokine on the offspring's allergy phenotype. RESULTS: We demonstrate that offspring from schistosome-infected mothers that were mated in the TH1 and regulatory phases, but not the TH2 immune phase, are protected against the onset of allergic airway inflammation. Interestingly, these effects were associated with distinctly altered schistosome-specific cytokine and gene expression profiles within the fetomaternal interface. Furthermore, we identified that it is not the transfer of helminth antigens but rather maternally derived IFN-γ during the acute phase of infection that is essential for the progeny's protective immune phenotype. CONCLUSION: Overall, we present a novel immune phase-dependent coherency between the maternal immune responses during schistosomiasis and the progeny's predisposition to allergy. Therefore, we propose to include helminth-mediated transmaternal immune modulation into the expanded hygiene hypothesis.


Assuntos
Citocinas/imunologia , Pneumonia/imunologia , Gravidez/imunologia , Hipersensibilidade Respiratória/imunologia , Esquistossomose mansoni/imunologia , Alérgenos/imunologia , Animais , Animais Recém-Nascidos , Citocinas/genética , Suscetibilidade a Doenças/imunologia , Feminino , Imunoglobulina E/imunologia , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Ovalbumina/imunologia
3.
Science ; 324(5927): 639-42, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19299585

RESUMO

The gamma-secretase complex plays a role in Alzheimer's disease and cancer progression. The development of clinically useful inhibitors, however, is complicated by the role of the gamma-secretase complex in regulated intramembrane proteolysis of Notch and other essential proteins. Different gamma-secretase complexes containing different Presenilin or Aph1 protein subunits are present in various tissues. Here we show that these complexes have heterogeneous biochemical and physiological properties. Specific inactivation of the Aph1B gamma-secretase in a mouse Alzheimer's disease model led to improvements of Alzheimer's disease-relevant phenotypic features without any Notch-related side effects. The Aph1B complex contributes to total gamma-secretase activity in the human brain, and thus specific targeting of Aph1B-containing gamma-secretase complexes may help generate less toxic therapies for Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Endopeptidases/metabolismo , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/genética , Peptídeos beta-Amiloides/análise , Peptídeos beta-Amiloides/química , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Endopeptidases/química , Endopeptidases/genética , Feminino , Humanos , Aprendizagem em Labirinto , Proteínas de Membrana/metabolismo , Memória , Camundongos , Neurônios/metabolismo , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/metabolismo , Peptídeo Hidrolases/metabolismo , Presenilina-1/química , Presenilina-1/genética , Presenilina-1/metabolismo , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais
4.
J Biol Chem ; 283(25): 17049-54, 2008 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-18426795

RESUMO

Proteolytic processing of the amyloid precursor protein by beta- and gamma-secretase generates the amyloid-beta (Abeta) peptides, which are principal drug targets in Alzheimer disease therapeutics. gamma-Secretase has imprecise cleavage specificity and generates the most abundant Abeta40 and Abeta42 species together with longer and shorter peptides such as Abeta38. Several mechanisms could explain the production of multiple Abeta peptides by gamma-secretase, including sequential processing of longer into shorter Abeta peptides. A novel class of gamma-secretase modulators (GSMs) that includes some non-steroidal anti-inflammatory drugs has been shown to selectively lower Abeta42 levels without a change in Abeta40 levels. A signature of GSMs is the concomitant increase in shorter Abeta peptides, such as Abeta38, leading to the suggestion that generation of Abeta42 and Abeta38 peptide species by gamma-secretase is coordinately regulated. However, no evidence for or against such a precursor-product relationship has been provided. We have previously shown that stable overexpression of aggressive presenilin-1 (PS1) mutations associated with early-onset familial Alzheimer disease attenuated the cellular response to GSMs, resulting in greatly diminished Abeta42 reductions as compared with wild type PS1. We have now used this model system to investigate whether Abeta38 production would be similarly affected indicating coupled generation of Abeta42 and Abeta38 peptides. Surprisingly, treatment with the GSM sulindac sulfide increased Abeta38 production to similar levels in four different PS1 mutant cell lines as compared with wild type PS1 cells. This was confirmed with the structurally divergent GSMs ibuprofen and indomethacin. Mass spectrometry analysis and high resolution urea gel electrophoresis further demonstrated that sulindac sulfide did not induce detectable compensatory changes in levels of other Abeta peptide species. These data provide evidence that Abeta42 and Abeta38 species can be independently generated by gamma-secretase and argue against a precursor-product relationship between these peptides.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Sequência de Aminoácidos , Animais , Células CHO , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Humanos , Ibuprofeno/farmacologia , Dados de Sequência Molecular , Mutação , Presenilina-1/genética , Sulindaco/análogos & derivados , Sulindaco/farmacologia
5.
Proteomics ; 7(20): 3815-20, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17924594

RESUMO

The detailed analysis of beta-amyloid (Abeta) peptides in human plasma is still hampered by the limited sensitivity of available mass spectrometric methods and the lack of appropiate ELISAs to measure Abeta peptides other than Abeta(1-38), Abeta(1-40), and Abeta(1-42). By combining high-yield Abeta immuno- precipitation (IP), IEF, and urea-based Abeta-SDS-PAGE-immunoblot, at least 30 Abeta-immuno-reactive spots were detected in human plasma samples as small as 1.6 mL. This approach clearly resolved Abeta peptides Abeta(1-40), Abeta(1-42), Abeta(1-37), Abeta(1-38), Abeta(1-39), the N-truncated Abeta(2-40), Abeta(2-42), and, for the first time, also Abeta(1-41). Relative quantification indicated that Abeta(1-40) and Abeta(1-42) accounted for less than 60% of the total amount of Abeta peptides in plasma. All other Abeta peptides appear to be either C-terminally or N-terminally truncated forms or as yet uncharacterized Abeta species which migrated as trains of spots with distinct pIs. The Abeta pattern found in cerebrospinal fluid (CSF) was substantially less complex. This sensitive method (2-D Abeta-WIB) might help clarifying the origin of distinct Abeta species from different tissues, cell types, or intracellular pools as well as their amyloidogenicity. It might further help identifying plasma Abeta species suitable as biomarkers for the diagnosis of Alzheimer's disease (AD).


Assuntos
Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/química , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/química , Ureia , Doença de Alzheimer/sangue , Eletroforese em Gel Bidimensional , Humanos , Pessoa de Meia-Idade
6.
Electrophoresis ; 25(20): 3336-43, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15490456

RESUMO

In this prospective study, for the first time we have separated and quantified amyloid beta (Abeta) peptides in the plasma of patients with Alzheimer's disease (AD, n = 8) and age- and environment-matched healthy controls (n = 9) with urea-based Abeta-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)/immunoblot. In addition to the Abeta peptides 1-37/38/39/40/42, which we recently identified as regular constituents of human cerebrospinal fluid (CSF), we have observed a novel electrophoretic band migrating slightly cathodically to Abeta1-42. Since a standard peptide with the amino acid sequence Abeta2-40 migrates in the same position, we hypothesize that this plasma-specific band may correspond to Abeta2-40. The concentration of Abeta peptides in the plasma has been approximately 100-fold lower compared to the CSF. Interestingly, the concentration of the two shortest peptides and the longest one of these considered here (i.e., Abeta1-37/38/42) have increased significantly when the samples have been frozen at -80 degrees C before immunoprecipitation, while the 'middle-length' peptides (i.e., Abeta1-39/40) have not been affected by this procedure. We have not observed significant differences of the Abeta peptides concentrations between AD and control subjects. Our method can be used to investigate the significance of plasma Abeta peptides in neurodegenerative disorders, and to monitor the efficiency of drugs with beta/gamma-secretase inhibitory potency.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/sangue , Eletroforese em Gel de Poliacrilamida , Fragmentos de Peptídeos/sangue , Idoso , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/imunologia , Peptídeos beta-Amiloides/isolamento & purificação , Humanos , Imunoprecipitação , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/isolamento & purificação
7.
Ann Neurol ; 54(2): 263-7, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12891683

RESUMO

Decreased levels of beta-amyloid peptide 1-42 (Abeta1-42) in cerebrospinal fluid (CSF) are a characteristic feature of Alzheimer's disease (AD) but recently were also observed in Creutzfeldt-Jakob disease (CJD). We analyzed the CSF of patients with CJD, and AD and nondemented controls using a quantitative urea-based Abeta sodium dodecyl sulfate polyacrylamide gel electrophoresis immunoblot. Like in AD and nondemented controls, we found a highly conserved pattern of carboxyterminally truncated Abeta1-37/38/39 in addition to Abeta1-40/42 also in CJD patients. By the introduction of the ratio Abeta1-39 to Abeta1-42, CJD and AD can effectively be differentiated. We conclude that the immunoblot shows disease-specific CSF Abeta peptide patterns in CJD and AD and suppose that measurement of the Abeta peptide pattern seems to be a promising diagnostic tool in the differential diagnosis of dementias.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Síndrome de Creutzfeldt-Jakob/líquido cefalorraquidiano , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Apolipoproteínas E/líquido cefalorraquidiano , Eletroforese em Gel de Poliacrilamida , Encefalite/líquido cefalorraquidiano , Feminino , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
8.
Immunity ; 17(3): 277-88, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12354381

RESUMO

Mice lacking the receptor tyrosine kinase c-Kit (c-Kit(W/W)) have hematopoietic defects causing perinatal death. We have identified a viable c-Kit(W/W) mouse, termed the "Vickid" mouse. Around birth, c-Kit plays a redundant role in T and no role in B cell development. Here, we show an age-dependent, progressive decline of pro-T and pro-B cells accompanied by loss of common lymphoid progenitors in the bone marrow in adult mice lacking c-Kit. Adult c-Kit(W/W) hematopoietic stem cells can engraft in host bone marrow but fail to radioprotect, form spleen colonies, or establish sustained lymphopoiesis. These defects in adult T and B cell development are also evident in a second viable c-Kit(W/W) strain, rescued by overexpression of erythropoietin.


Assuntos
Hematopoese/genética , Células-Tronco Hematopoéticas/patologia , Síndromes de Imunodeficiência/genética , Proteínas Proto-Oncogênicas c-kit/genética , Transferência Adotiva , Envelhecimento/imunologia , Albinismo/genética , Alelos , Animais , Linfócitos B/patologia , Células da Medula Óssea/patologia , Ensaio de Unidades Formadoras de Colônias , Eritropoese/genética , Feminino , Sobrevivência de Enxerto , Hematopoese/fisiologia , Células-Tronco Hematopoéticas/química , Íntrons/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fenótipo , Mutação Puntual , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-kit/fisiologia , Splicing de RNA/genética , Quimera por Radiação , Organismos Livres de Patógenos Específicos , Baço/patologia , Transplante de Células-Tronco , Linfócitos T/patologia
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