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1.
Complement Ther Clin Pract ; 49: 101643, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36029556

RESUMO

BACKGROUND AND PURPOSE: Touch for health (TFH) based kinesiology is a complementary therapy with foundations in a natural health training developed utilising techniques from chiropractic, osteopathy and acupressure therapies. Although popular, the impact of the therapy is poorly understood. The aim of this study was to understand outcomes of TFH-based kinesiology interventions that clients perceive as important in their lives. MATERIALS AND METHODS: A qualitative phenomenological approach was chosen to capture rich descriptive data. Thirteen individuals were recruited from TFH-based kinesiology practices. Focus groups included semi-structured questions, photo-elicitation and a wellness word activity to prompt discussion on impacts of interventions. Audio-recordings were transcribed, coded and grouped to develop themes. Comparisons were made and linked with the wellness model, theory of planned behaviour and mindfulness-based interventions. RESULTS: Three interrelated themes emerged: impact on awareness, experience of effects and impact on action. TFH-based kinesiology was perceived to enhance self-awareness and feelings of wellbeing, promote self-care and support new actions to manage stress and complement conventional healthcare. The use of a mind-body approach with feedback from muscle testing and less need for dialogue were valued. Photo-elicitation generated rich narratives recounting experiences after interventions. Impacts aligned with the wellness model and resembled outcomes of mindfulness-based interventions. CONCLUSION: This study provides an insight into experiences and impacts of TFH-based kinesiology. Interventions were seen to facilitate self-awareness, experiences of wellbeing and promote self-care. Findings contribute towards a knowledge-base to foster dialogue and inform TFH-based kinesiologists, health professionals, consumers and research of TFH-based kinesiology and comparative therapies.


Assuntos
Atenção Plena , Tato , Humanos , Pesquisa Qualitativa , Terapias Mente-Corpo , Emoções
2.
ACS Omega ; 6(41): 26846-26856, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34693106

RESUMO

The ring opening of 2α,3α- and 2ß,3ß-epoxy-5α-androstan-17-one with halide reagents (AlCl3, TMSCl, LiCl, and LiBr) was investigated using imidazolium ionic liquids in the dual role of solvent and catalyst. The application of the ionic liquid was shown to result in an increase in the amount of the unusual diequatorial halohydrins especially at temperatures above 100 °C. With a careful choice of reaction conditions, the latter derivatives could be produced with 43-96% selectivity depending on the nature of the halide ion. Moreover, the usual diaxial products could also be isolated in 70-85% yields by a proper change in the reaction conditions. The reusability of the ionic liquid was demonstrated in both types of reactions. The structures of the products were proved unequivocally by nuclear magnetic resonance (NMR) measurements including two-dimensional (2D) techniques as well as high-resolution mass spectrometry (HRMS). Based on quantum chemical calculations, the effect of the ionic liquid could be explained by the stabilization of the transition state leading to the diequatorial product.

3.
Eur J Med Chem ; 222: 113560, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111828

RESUMO

HTS campaign of the corporate compound collection resulted in a novel, oxalic acid diamide scaffold of α7 nACh receptor positive allosteric modulators. During the hit expansion, several derivatives, such as 4, 11, 17 demonstrated not only high in vitro potency, but also in vivo efficacy in the mouse place recognition test. The advanced hit molecule 11 was further optimized by the elimination of the putatively mutagenic aromatic-amine building block that resulted in a novel, aminomethylindole compound family. The most balanced physico-chemical and pharmacological profile was found in case of compound 55. Docking study revealed an intersubunit binding site to be the most probable for our compounds. 55 demonstrated favorable cognitive enhancing profile not only in scopolamine-induced amnesia (place recognition test in mice) but also in natural forgetting (novel object recognition test in rats). Compound 55 was, furthermore, active in a cognitive paradigm of high translational value, namely in the rat touch screen visual discrimination test. Therefore, 55 was selected as a lead compound for further optimization. Based on the obtained favorable results, the invented aminomethylindole cluster may provide a viable approach for cognitive enhancement through positive allosteric modulation of α7 nAChRs.


Assuntos
Amidas/farmacologia , Descoberta de Drogas , Ensaios de Triagem em Larga Escala , Ácido Oxálico/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Regulação Alostérica/efeitos dos fármacos , Amidas/síntese química , Amidas/química , Animais , Relação Dose-Resposta a Droga , Humanos , Masculino , Estrutura Molecular , Ácido Oxálico/síntese química , Ácido Oxálico/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade
4.
Eur J Med Chem ; 214: 113189, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33540354

RESUMO

The paper focuses on the scaffold hopping-based discovery and characterization of novel nicotinic alpha 7 receptor positive modulator (α7 nAChR PAM) ligands around the reference molecule (A-867744). First, substantial efforts were carried out to assess the importance of the various pharmacophoric elements on the in vitro potency (SAR evaluation) by chemical modifications. Subsequently, several new derivatives with versatile, heteroaromatic central cores were synthesized and characterized. A promising, pyrazole-containing new chemotype with good physicochemical and in vitro parameters was identified. Retrospective analysis based on homology modeling was also carried out. Besides its favorable in vitro characteristics, the most advanced derivative 69 also showed in vivo efficacy in a rodent model of cognition (scopolamine-induced amnesia in the mouse place recognition test) and acceptable pharmacokinetic properties. Based on the in vivo data, the resulting molecule with advanced drug-like characteristics has the possibility to improve cognitive performance in a biologically relevant dose range, further strengthening the view of the supportive role of α7 nACh receptors in the cognitive processes.


Assuntos
Descoberta de Drogas , Agonistas Nicotínicos/farmacologia , Pirazóis/farmacologia , Administração Oral , Regulação Alostérica/efeitos dos fármacos , Amnésia/induzido quimicamente , Amnésia/tratamento farmacológico , Amnésia/metabolismo , Animais , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Agonistas Nicotínicos/administração & dosagem , Agonistas Nicotínicos/metabolismo , Pirazóis/administração & dosagem , Pirazóis/metabolismo , Ratos , Ratos Wistar , Escopolamina , Relação Estrutura-Atividade , Receptor Nicotínico de Acetilcolina alfa7
5.
Arch Dis Child ; 105(11): 1086-1092, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32398323

RESUMO

OBJECTIVE: Somatic symptom and related disorders (SSRDs) are prevalent, heterogenous conditions that have the potential to profoundly affect normative function in children and adolescents. Yet there is little understanding of pathways to recovery. This study aimed to systematically scope how functional recovery has been measured in children and adolescents with SSRD . DESIGN: Scoping review of primary studies. METHOD: Medline (Ovid) and PsychInfo were systematically searched for publications from January 1998 to April 2019. Primary studies in English that reported functional outcomes of children and adolescents with SSRD were included. Case reports and population studies were excluded. Within the tools and clinician notes, the core domains of functional outcome were identified. RESULTS: Sixteen studies were identified that used 11 different functional outcome tools. The domains assessed within these functional outcome tools, together with the domains noted by clinicians, included physical and mental health symptoms, as well as school attendance and academic outcomes, recreational participation, impact on family and service utilisation. There was no evidence of a preferred outcome measure as only two of the tools were used in more than one study. CONCLUSIONS: The variability of tools and domains used to measure functional recovery in children and adolescents with SSRD suggests lack of conceptual agreement about what constitutes functional recovery. Continued focus on symptom measurement or mental health comorbidities risks limiting research to single types of disorder (eg, functional neurological disability) or interventions, which threatens a much needed wider research agenda around appropriate treatment, including of complex and persistent disorders.


Assuntos
Transtornos Somatoformes/terapia , Adolescente , Criança , Humanos , Indução de Remissão , Transtornos Somatoformes/diagnóstico
6.
Cell Rep ; 1(3): 185-90, 2012 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-22832192

RESUMO

Plasminogen is the proenzyme precursor of the primary fibrinolytic protease plasmin. Circulating plasminogen, which comprises a Pan-apple (PAp) domain, five kringle domains (KR1-5), and a serine protease (SP) domain, adopts a closed, activation-resistant conformation. The kringle domains mediate interactions with fibrin clots and cell-surface receptors. These interactions trigger plasminogen to adopt an open form that can be cleaved and converted to plasmin by tissue-type and urokinase-type plasminogen activators. Here, the structure of closed plasminogen reveals that the PAp and SP domains, together with chloride ions, maintain the closed conformation through interactions with the kringle array. Differences in glycosylation alter the position of KR3, although in all structures the loop cleaved by plasminogen activators is inaccessible. The ligand-binding site of KR1 is exposed and likely governs proenzyme recruitment to targets. Furthermore, analysis of our structure suggests that KR5 peeling away from the PAp domain may initiate plasminogen conformational change.


Assuntos
Plasminogênio/química , Cristalografia por Raios X , Ativação Enzimática , Glicosilação , Humanos , Kringles , Modelos Moleculares , Mutação/genética , Ligação Proteica , Estrutura Secundária de Proteína
7.
Thromb Haemost ; 107(5): 854-63, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22399118

RESUMO

Protein Z-dependent protease inhibitor (ZPI) is a plasma inhibitor of factor (F)Xa and FXIa. In an earlier study, five mutations were identified within the ZPI gene of venous thrombosis patients and healthy controls. Two of these were nonsense mutations and three were missense mutations in important regions of the protein. Here we report that two of these latter three mutations, F145L and Q384R, impair the inhibitory function of ZPI in vitro. Recombinant wild-type and mutant proteins were prepared; stability in response to thermal challenge was similar. Inhibition of FXa in the presence of the cofactor protein Z was reduced 68-fold by the Q384R mutant; inhibition of FXIa by the F145L mutant was reduced two- to three-fold compared to the wild-type ZPI. An analysis of all five ZPI mutations was undertaken in a cohort of venous thrombosis patients (n=550) compared to healthy controls (n=600). Overall, there was a modest increase in incidence of these mutations in the thrombosis group (odds ratio 2.0, 1.05-3.7, p=0.044). However, in contrast to W324X (nonsense mutation), the Q384R missense mutation and R88X nonsense mutation were evenly distributed in patients and controls; F145L was rare. The final mutation (S143Y) was also rare and did not significantly alter ZPI function in laboratory studies. The F145L and particularly the Q384R mutation impaired the function of the coagulation inhibitor ZPI; however, there was no convincing association between these mutations and venous thrombosis risk. The functional role for ZPI in vivo has yet to be clarified.


Assuntos
Coagulação Sanguínea/genética , Mutação de Sentido Incorreto , Serpinas/genética , Trombose Venosa/genética , Adulto , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Estabilidade Enzimática , Fator XIa/metabolismo , Fator Xa/metabolismo , Feminino , Frequência do Gene , Genótipo , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Razão de Chances , Fenótipo , Conformação Proteica , Desnaturação Proteica , Proteínas Recombinantes/metabolismo , Medição de Risco , Fatores de Risco , Serpinas/sangue , Serpinas/química , Relação Estrutura-Atividade , Trombose Venosa/sangue , Trombose Venosa/enzimologia
8.
Methods Enzymol ; 501: 223-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22078537

RESUMO

The serpin molecule has evolved an unusual mechanism of inhibition, involving an exposed reactive center loop (RCL) and conformational change to covalently trap a target protease. Successful inhibition of the protease is dependent on the rate of serpin-protease association and the efficiency with which the RCL inserts into ß-sheet A, translocating the covalently bound protease and thereby completing the inhibition process. This chapter describes the kinetic methods used for determining the rate of protease inhibition (k(a)) and the stoichiometry of inhibition. These kinetic variables provide a means to examine different serpin-protease pairings, assess the effects of mutations within a serpin on protease inhibition, and determine the physiologically cognate protease of a serpin.


Assuntos
Bioquímica/métodos , Bioensaio , Serina Proteases/metabolismo , Serpinas/metabolismo , Animais , Sítios de Ligação , Galinhas , Relação Dose-Resposta a Droga , Humanos , Cinética , Ligação Proteica/efeitos dos fármacos , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Serina Proteases/química , Serpinas/química , Serpinas/farmacologia , Espectrometria de Fluorescência
9.
J Org Chem ; 76(15): 6048-56, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21668005

RESUMO

Ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim](+)[PF(6)](-)) and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim](+)[BF(4)](-)) were found to promote an unusual Wagner-Meerwein rearrangement of steroidal 16α,17α-epoxides leading to unnatural 13-epi-18-nor-16-one derivatives as the main products. These compounds were isolated in good to excellent yields. 16α-Hydroxy-Δ(13)-18-norsteroids, the results of the usual rearrangement, were obtained as minor components of the reaction mixtures. The ionic liquid [bmim](+)[PF(6)](-) was shown to induce C-ring aromatization of 16α,17α-epoxyestranes due to the formation of HF, the hydrolysis product of [PF(6)](-). Increasing amounts of HF and [PO(2)F(2)](-) were detected by (19)F and (31)P NMR when the ionic liquid was reused. The structures of the steroidal products, 16-oxo-18-nor-13α-steroid derivatives, 16α-hydroxy-Δ(13)-18-norsteroids, and C-aromatic compounds were determined by two-dimensional NMR techniques and high-resolution mass spectrometry (HRMS). The ionic liquids were recirculated efficiently.


Assuntos
Androstanóis/química , Estranos/química , Imidazóis/química , Líquidos Iônicos/química , Estrutura Molecular , Estereoisomerismo
10.
J Biol Chem ; 286(28): 24544-52, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21543325

RESUMO

α(2)-Antiplasmin is the physiological inhibitor of plasmin and is unique in the serpin family due to N- and C-terminal extensions beyond its core domain. The C-terminal extension comprises 55 amino acids from Asn-410 to Lys-464, and the lysine residues (Lys-418, Lys-427, Lys-434, Lys-441, Lys-448, and Lys-464) within this region are important in mediating the initial interaction with kringle domains of plasmin. To understand the role of lysine residues within the C terminus of α(2)-antiplasmin, we systematically and sequentially mutated the C-terminal lysines, studied the effects on the rate of plasmin inhibition, and measured the binding affinity for plasmin via surface plasmon resonance. We determined that the C-terminal lysine (Lys-464) is individually most important in initiating binding to plasmin. Using two independent methods, we also showed that the conserved internal lysine residues play a major role mediating binding of the C terminus of α(2)-antiplasmin to kringle domains of plasmin and in accelerating the rate of interaction between α(2)-antiplasmin and plasmin. When the C terminus of α(2)-antiplasmin was removed, the binding affinity for active site-blocked plasmin remained high, suggesting additional exosite interactions between the serpin core and plasmin.


Assuntos
Fibrinolisina/química , alfa 2-Antiplasmina/química , Substituição de Aminoácidos , Domínio Catalítico/fisiologia , Fibrinolisina/genética , Fibrinolisina/metabolismo , Humanos , Mutação de Sentido Incorreto , Mapeamento de Peptídeos/métodos , Ligação Proteica/fisiologia , Domínios e Motivos de Interação entre Proteínas/fisiologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , alfa 2-Antiplasmina/genética , alfa 2-Antiplasmina/metabolismo
12.
Blood ; 111(4): 2049-52, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18063751

RESUMO

The serpin alpha(2)-antiplasmin (SERPINF2) is the principal inhibitor of plasmin and inhibits fibrinolysis. Accordingly, alpha(2)-antiplasmin deficiency in humans results in uncontrolled fibrinolysis and a bleeding disorder. alpha(2)-antiplasmin is an unusual serpin, in that it contains extensive N- and C-terminal sequences flanking the serpin domain. The N-terminal sequence is crosslinked to fibrin by factor XIIIa, whereas the C-terminal region mediates the initial interaction with plasmin. To understand how this may happen, we have determined the 2.65A X-ray crystal structure of an N-terminal truncated murine alpha(2)-antiplasmin. The structure reveals that part of the C-terminal sequence is tightly associated with the body of the serpin. This would be anticipated to position the flexible plasmin-binding portion of the C-terminus in close proximity to the serpin Reactive Center Loop where it may act as a template to accelerate serpin/protease interactions.


Assuntos
alfa 2-Antiplasmina/química , Animais , Antifibrinolíticos/química , Cristalografia por Raios X , Camundongos , Modelos Moleculares , Fragmentos de Peptídeos/química , Conformação Proteica , Proteínas Recombinantes/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , alfa 2-Antiplasmina/genética
13.
Biochem J ; 405(3): 489-94, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17447896

RESUMO

Centerin [SERPINA9/GCET1 (germinal centre B-cell-expressed transcript 1)] is a serpin (serine protease inhibitor) whose expression is restricted to germinal centre B-cells and lymphoid malignancies with germinal centre B-cell maturation. Expression of centerin, together with bcl-6 and GCET2, constitutes a germinal centre B-cell signature, which is associated with a good prognosis in diffuse large B-cell lymphomas, but the molecular basis for this remains to be elucidated. We report here the cloning, expression and molecular characterization of bacterial recombinant centerin. Biophysical studies demonstrated that centerin was able to undergo the 'stressed to relaxed' conformational change which is an absolute requirement for protease inhibitory activity. Kinetic analysis showed that centerin rapidly inhibited the serine protease trypsin (k(a)=1.9x10(5) M(-1) x s(-1)) and also demonstrated measurable inhibition of thrombin (k(a)=1.17x10(3) M(-1) x s(-1)) and plasmin (k(a)=1.92x10(3) M(-1) x s(-1)). Centerin also bound DNA and unfractionated heparin, although there was no functionally significant impact on the rate of inhibition. These results suggest that centerin is likely to function in vivo in the germinal centre as an efficient inhibitor of a trypsin-like protease.


Assuntos
Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Serpinas/química , Serpinas/metabolismo , Linhagem Celular Tumoral , Clonagem Molecular , Regulação da Expressão Gênica , Histidina , Humanos , Cinética , Proteínas de Neoplasias/genética , Serpinas/genética
14.
J Phys Chem B ; 110(31): 15417-25, 2006 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-16884263

RESUMO

Au-TiO(2) interface on silica support was aimed to be produced in a controlled way by use of Au hydrosol. In method A, the Au colloids were modified by hydrolysis of the water-soluble Ti(IV) bis(ammoniumlactato)dihydroxide (TALH) precursor and then adsorbed on Aerosil SiO(2) surface. In method B, Au sol was first deposited onto the SiO(2) surface and then TALH was adsorbed on it. Regular and high-resolution transmission electron microscopy (TEM and HRTEM) and energy dispersive spectrometry (EDS) analysis allowed us to conclude that, in method A, gold particles were able to retain the precursor of TiO(2) at 1.5 wt % TiO(2) loading, but at 4 wt % TiO(2) content the promoter oxide appeared over the silica surface as well. With method B, titania was detected on silica at each TiO(2) concentration. In Au-TiO(2)/SiO(2) samples, the stability of Au particles against sintering was much higher than in Au/TiO(2). The formation of an active Au-TiO(2) perimeter was proven by the greatly increased CO oxidation activity compared to that of the reference Au/SiO(2).

15.
Steroids ; 71(8): 706-11, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16750547

RESUMO

Efficient ring opening of steroidal 2,3-epoxides with stoichiometric amount of aromatic amines has been carried out using an ionic liquid ([bmim](+)[BF(4)](-)) both as solvent and catalyst. The reactions were completely regio- and stereoselective in each case. The aminoalcohol products have chair conformations in ring A. The ionic liquid-mediated ring opening can efficiently be carried out with aliphatic amines like morpholine as well.


Assuntos
Aminoácidos Aromáticos/química , Amino Álcoois/síntese química , Íons/química , Solventes/química , Esteroides Heterocíclicos/química , Compostos de Anilina/química , Catálise , Cetosteroides/síntese química , Cetosteroides/química , Modelos Biológicos , Conformação Molecular
16.
J Biol Chem ; 280(52): 43168-78, 2005 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-16141197

RESUMO

Antichymotrypsin (SERPINA3) is a widely expressed member of the serpin superfamily, required for the regulation of leukocyte proteases released during an inflammatory response and with a permissive role in the development of amyloid encephalopathy. Despite its biological significance, there is at present no available structure of this serpin in its native, inhibitory state. We present here the first fully refined structure of a murine antichymotrypsin orthologue to 2.1 A, which we propose as a template for other antichymotrypsin-like serpins. A most unexpected feature of the structure of murine serpina3n is that it reveals the reactive center loop (RCL) to be partially inserted into the A beta-sheet, a structural motif associated with ligand-dependent activation in other serpins. The RCL is, in addition, stabilized by salt bridges, and its plane is oriented at 90 degrees to the RCL of antitrypsin. A biochemical and biophysical analysis of this serpin demonstrates that it is a fast and efficient inhibitor of human leukocyte elastase (ka: 4 +/- 0.9 x 10(6) m(-1) s(-)1) and cathepsin G (ka: 7.9 +/- 0.9 x 10(5) m(-1) s(-)1) giving a spectrum of activity intermediate between that of human antichymotrypsin and human antitrypsin. An evolutionary analysis reveals that residues subject to positive selection and that have contributed to the diversity of sequences in this sub-branch (A3) of the serpin superfamily are essentially restricted to the P4-P6' region of the RCL, the distal hinge, and the loop between strands 4B and 5B.


Assuntos
Serpinas/química , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Dicroísmo Circular , Códon , Cristalografia por Raios X , Evolução Molecular , Humanos , Inflamação , Cinética , Elastase de Leucócito/metabolismo , Leucócitos/patologia , Ligantes , Funções Verossimilhança , Camundongos , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Filogenia , Conformação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Sais/farmacologia , Homologia de Sequência de Aminoácidos , Serpinas/fisiologia , Temperatura , Treonina/química , Fatores de Tempo , Tripsina/química , Tripsina/farmacologia
17.
J Exp Med ; 201(7): 1077-88, 2005 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-15795238

RESUMO

Mobilization of hematopoietic progenitor cells into the blood involves a massive release of neutrophil serine proteases in the bone marrow. We hypothesize that the activity of these neutrophil serine proteases is regulated by the expression of naturally occurring inhibitors (serpina1 and serpina3) produced locally within the bone marrow. We found that serpina1 and serpina3 were transcribed in the bone marrow by many different hematopoietic cell populations and that a strong reduction in expression occurred both at the protein and mRNA levels during mobilization induced by granulocyte colony-stimulating factor or chemotherapy. This decreased expression was restricted to the bone marrow as serpina1 expression was maintained in the liver, leading to no change in plasma concentrations during mobilization. The down-regulation of serpina1 and serpina3 during mobilization may contribute to a shift in the balance between serine proteases and their inhibitors, and an accumulation of active neutrophil serine proteases in bone marrow extravascular fluids that cleave and inactivate molecules essential to the retention of hematopoietic progenitor cells within the bone marrow. These data suggest an unexpected role for serpina1 and serpina3 in regulating the bone marrow hematopoietic microenvironment as well as influencing the migratory behavior of hematopoietic precursors.


Assuntos
Medula Óssea/metabolismo , Regulação para Baixo , Células-Tronco Hematopoéticas/metabolismo , RNA Mensageiro/metabolismo , Serpinas/metabolismo , alfa 1-Antitripsina/metabolismo , Animais , Movimento Celular/fisiologia , Líquido Extracelular/metabolismo , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Immunoblotting , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serpinas/genética , Serpinas/fisiologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , alfa 1-Antitripsina/fisiologia
18.
J Mol Evol ; 59(4): 488-97, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15638460

RESUMO

Members of the serpin (serine protease inhibitor) superfamily of genes are well represented in both human and murine genomes. In many cases it is possible to identify a definite ortholog on the basis of sequence similarity and by examining the surrounding genes at syntenic loci. We have recently examined the murine serpin locus at 12F1 and observed that the single human alpha1-antichymotrypsin gene is represented by 14 paralogs. It is also known that the single human alpha1-antitrypsin gene has five paralogs in the mouse. The forces driving this gene multiplication are unknown and there are no data describing the function of the various serpin gene products at the alpha1-antichymotrypsin multigene locus. Examination of the predicted amino acid sequences shows that the serpins are likely to be functional protease inhibitors but with differing target protease specificities. In order to begin to address the question of the problem presented by the murine alpha1-antichymotrypsins, we have used RT-PCR to examine the expression pattern of these serpin genes. Our data show that the divergent reactive center loop sequence, and predictably variable target protease specificity, is reflected in tissue-specific expression for many of the family members. These observations add weight to the hypothesis that the antichymotrypsin-like serpins have an evolutionary importance which has led to their expansion and diversification in multiple species.


Assuntos
Evolução Molecular , Camundongos/genética , Serpinas/genética , Animais , Sequência de Bases , Linhagem Celular , Expressão Gênica , Variação Genética , Humanos , Fígado/enzimologia , Fígado/metabolismo , Dados de Sequência Molecular , Locos de Características Quantitativas , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Serpinas/metabolismo
19.
Genomics ; 81(3): 336-45, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12659817

RESUMO

The major human plasma protease inhibitors, alpha(1)-antitrypsin and alpha(1)-antichymotrypsin, are each encoded by a single gene, whereas in the mouse they are represented by clusters of 5 and 14 genes, respectively. Although there is a high degree of overall sequence similarity within these groupings, the reactive-center loop (RCL) domain, which determines target protease specificity, is markedly divergent. The literature dealing with members of these mouse serine protease inhibitor (serpin) clusters has been complicated by inconsistent nomenclature. Furthermore, some investigators, unaware of the complexity of the family, have failed to distinguish between closely related genes when measuring expression levels or functional activity. We have reviewed the literature dealing with the mouse equivalents of human alpha(1)-antitrypsin and alpha(1)-antichymotrypsin and made use of the recently completed mouse genome sequence to propose a systematic nomenclature. We have also examined the extended mouse clade "a" serpin cluster at chromosome 12F1 and compared it with the syntenic region at human chromosome 14q32. In summarizing the literature and suggesting a standardized nomenclature, we aim to provide a logical structure on which future research may be based.


Assuntos
Família Multigênica , alfa 1-Antiquimotripsina/genética , alfa 1-Antitripsina/genética , Sequência de Aminoácidos , Animais , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade , alfa 1-Antiquimotripsina/química , alfa 1-Antitripsina/química
20.
Biochem J ; 371(Pt 1): 165-73, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12470299

RESUMO

Murine serpin 2A is expressed at high levels in haemopoietic progenitors and down-regulated on differentiation. When it is constitutively expressed in the multipotent haemopoietic cell line, FDCP-Mix, it causes a delay in differentiation and increased clonogenic potential. The serpin is also dramatically up-regulated on T-cell activation. It has an unusual reactive site Cys-Cys sequence, a unique C-terminal extension and lacks a typical cleavable N-terminal signal sequence. In spite of these features, the protein is not a member of the ovalbumin-serpin family, but is instead most closely related to human antichymotrypsin. We have shown that the serpin is intracellular with prominent nuclear localization. Transverse urea gradient gels and CD studies show that the protein undergoes the stressed-relaxed conformational change typical of inhibitory serpins. However, we have not detected complex-forming activity with a set of proteases. Thermal denaturation studies also show that the protein has decreased structural stability under reducing conditions, although it lacks disulphide bonds within the core of the molecule. Our results show that serpin 2A is an intracellular protein with the potential to mediate its biological effects via interaction with non-protease intracellular targets. Furthermore, the results presented suggest a model whereby the serpin interactions could be modulated by redox conditions or conformational change induced by cleavage of the reactive-site loop.


Assuntos
Serpinas/química , Serpinas/metabolismo , Animais , Núcleo Celular/metabolismo , Células Cultivadas , Dicroísmo Circular , Citoplasma/metabolismo , Endopeptidases/metabolismo , Camundongos , Modelos Moleculares , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/metabolismo , Oxirredução , Ligação Proteica , Conformação Proteica , Desnaturação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Serpinas/genética
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