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1.
Diabet Med ; 40(9): e15121, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37078256

RESUMO

AIMS: Gestational diabetes (GDM) is associated with the development of postpartum (PP) glucose intolerance. Plasma glycated CD59 (pGCD59) is an emerging biomarker for the detection of hyperglycaemia. The aim of this study was to assess the ability of PP pGCD59 to predict the development of PP GI as defined by the 2 h 75 g OGTT using the ADA criteria, in a cohort of women diagnosed with prior GDM in the index pregnancy using the 2 h 75 g OGTT at 24-28 weeks of gestation according to the World Health Organization (WHO) 2013 criteria. METHODS: Of the 2017 pregnant women recruited prospectively 140 women with gestational diabetes had samples for pGCD59 taken PP at the time of the OGTT. The ability of pGCD59 to predict the results of the PP OGTT was assessed using nonparametric receiver operating characteristic (ROC) curves. RESULTS: Women with PP glucose intolerance had significantly higher PP pGCD59 levels compared to women with normal glucose tolerance PP (3.8 vs. 2.7 SPU). PP pGCD59 identified women who developed glucose intolerance PP with an AUC of 0.80 (95% CI: 0.70-0.91). A PP pGCD59 cut-off value of 1.9 SPU generated a sensitivity of 100% (95% CI: 83.9-100), specificity of 16.9% (95% CI: 9.8-26.3), positive predictive value of 22.1% (95% CI: 21.0-22.6), and negative predictive value of 100% (95% CI: 87.4-100). PP fasting plasma glucose generated an AUC of 0.96 (95% CI: 0.89-0.99) for the identification of PP glucose intolerance. CONCLUSION: Our study found that PP pGCD9 may be a promising biomarker to identify women not requiring PP glucose intolerance screening using the traditional OGTT. While the diagnostic accuracy of pGCD59 is good, fasting plasma glucose remains a better test for the identification of PP glucose intolerance.


Assuntos
Diabetes Gestacional , Intolerância à Glucose , Feminino , Gravidez , Humanos , Diabetes Gestacional/diagnóstico , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/epidemiologia , Estudos Prospectivos , Glicemia , Teste de Tolerância a Glucose , Estudos Retrospectivos , Período Pós-Parto , Biomarcadores , Antígenos CD59
2.
Bioorg Med Chem Lett ; 80: 129119, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36581302

RESUMO

The ternary complex (eIF2·GTP·Met-tRNAiMet) and the eIF4F complex assembly are two major regulatory steps in the eukaryotic translation initiation. Inhibition of the ternary complex assembly is therefore a promising target for the development of novel anti-cancer therapeutics. Building on the finding that clotrimazole (CLT), a molecular probe that depletes intracellular Ca2+ stores and subsequently induce eIF2α phosphorylation, inhibit translation initiation, and reduce preferentially the expression of oncoproteins over "housekeeping" ones,1-3 we undertook structure activity relationship (SAR) studies that identified 3,3-diarylindoline-2-one #1181 as an interesting scaffold. Compound #1181 also induce phosphorylation of eIF2α thereby reducing the availability of the ternary complex, which leads to inhibition of translation initiation.4 Our subsequent efforts focused on understanding SAR iterative lead optimization to enhance potency and improve bioavailability. Herein, we report a complementing study focusing on heavily substituted symmetric and asymmetric 3,3-(o,m-disubstituted)diarylindoline-2-ones. These compounds were evaluated by the dual luciferase reporter ternary complex assay that recapitualates phosphorylation of eIF2α in a quantitative manner. We also evaluated all compounds by sulforhodamine B assay, which measures the overall effect of compounds on cell proliferations and/or viability.


Assuntos
Compostos de Bifenilo , Fator de Iniciação 2 em Eucariotos , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fosforilação , Biossíntese de Proteínas
3.
Am J Hematol ; 92(11): 1198-1203, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28815695

RESUMO

Clinical and experimental evidences support a link between the complement system and the pathogenesis of diabetes complications. CD59, an extracellular cell membrane-anchored protein, inhibits formation of the membrane attack complex (MAC), the main effector of complement-mediated tissue damage. This complement regulatory activity of human CD59 (hCD59) is inhibited by hyperglycemia-induced ɛ-amino glycation of Lys41 . Biochemical and structural analyses of glycated proteins with known three-dimensional structure revealed that glycation of ɛ-amino lysyl residues occurs predominantly at "glycation motives" that include lysyl/lysyl pairs or proximity of a histidyl residue, in which the imidazolyl moiety is ≈ 5Å from the ɛ-amino group. hCD59 contains a distinctive Lys41 /His44 putative glycation motif within its active site. In a model of transgenic diabetic mice expressing in erythrocytes either the wild type or a H44Q mutant form of hCD59, we demonstrate in vivo that the His44 is required for Lys41 glycation and consequent functional inactivation of hCD59, as evidenced using a mouse erythrocytes hemolytic assay. Since (1) the His44 residue is not present in CD59 from other animal species and (2) humans are particularly prone to develop complications of diabetes, our results indicate that the Lys41 /His44 glycation motif in human CD59 may confer humans a higher risk of developing vascular disease in response to hyperglycemia.


Assuntos
Antígenos CD59/genética , Antígenos CD59/metabolismo , Eritrócitos/metabolismo , Regulação da Expressão Gênica , Histidina/metabolismo , Animais , Glicemia , Complicações do Diabetes/genética , Complicações do Diabetes/metabolismo , Diabetes Mellitus Experimental , Membrana Eritrocítica/metabolismo , Glicosilação , Hemólise , Humanos , Lisina/metabolismo , Camundongos , Camundongos Transgênicos , Mutação
4.
Proc Natl Acad Sci U S A ; 111(31): E3187-95, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25049413

RESUMO

The interaction of the eukaryotic translation initiation factor eIF4E with the initiation factor eIF4G recruits the 40S ribosomal particle to the 5' end of mRNAs, facilitates scanning to the AUG start codon, and is crucial for eukaryotic translation of nearly all genes. Efficient recruitment of the 40S particle is particularly important for translation of mRNAs encoding oncoproteins and growth-promoting factors, which often harbor complex 5' UTRs and require efficient initiation. Thus, inhibiting the eIF4E/eIF4G interaction has emerged as a previously unpursued route for developing anticancer agents. Indeed, we discovered small-molecule inhibitors of this eIF4E/eIF4G interaction (4EGIs) that inhibit translation initiation both in vitro and in vivo and were used successfully in numerous cancer-biology and neurobiology studies. However, their detailed molecular mechanism of action has remained elusive. Here, we show that the eIF4E/eIF4G inhibitor 4EGI-1 acts allosterically by binding to a site on eIF4E distant from the eIF4G binding epitope. Data from NMR mapping and high-resolution crystal structures are congruent with this mechanism, where 4EGI-1 attaches to a hydrophobic pocket of eIF4E between ß-sheet2 (L60-T68) and α-helix1 (E69-N77), causing localized conformational changes mainly in the H78-L85 region. It acts by unfolding a short 310-helix (S82-L85) while extending α-helix1 by one turn (H78-S82). This unusual helix rearrangement has not been seen in any previous eIF4E structure and reveals elements of an allosteric inhibition mechanism leading to the dislocation of eIF4G from eIF4E.


Assuntos
Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Hidrazonas/química , Hidrazonas/metabolismo , Tiazóis/química , Tiazóis/metabolismo , Regulação Alostérica , Sítios de Ligação , Cristalografia por Raios X , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação Eucariótico 4G/química , Humanos , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Peptídeos/química , Peptídeos/metabolismo , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Capuzes de RNA/metabolismo , Soluções
5.
Chembiochem ; 15(4): 595-611, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24458973

RESUMO

4EGI-1, the prototypic inhibitor of eIF4E/eIF4G interaction, was identified in a high-throughput screening of small-molecule libraries with the aid of a fluorescence polarization assay that measures inhibition of binding of an eIF4G-derived peptide to recombinant eIF4E. As such, the molecular probe 4EGI-1 has potential for the study of molecular mechanisms involved in human disorders characterized by loss of physiological restraints on translation initiation. A hit-to-lead optimization campaign was carried out to overcome the configurational instability in 4EGI-1, which stems from the E-to-Z isomerization of the hydrazone function. We identified compound 1 a, in which the labile hydrazone was incorporated into a rigid indazole scaffold, as a promising rigidified 4EGI-1 mimetic lead. In a structure-activity relationship study directed towards probing the structural latitude of this new chemotype as an inhibitor of eIF4E/eIF4G interaction and translation initiation we identified 1 d, an indazole-based 4EGI-1 mimetic, as a new and improved lead inhibitor of eIF4E/eIF4G interaction and a promising molecular probe candidate for elucidation of the role of cap-dependent translation initiation in a host of pathophysiological states.


Assuntos
Fator de Iniciação 4E em Eucariotos/metabolismo , Fator de Iniciação Eucariótico 4G/metabolismo , Hidrazonas/metabolismo , Indazóis/química , Tiazóis/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação Eucariótico 4G/antagonistas & inibidores , Humanos , Hidrazonas/química , Hidrazonas/farmacologia , Indazóis/síntese química , Indazóis/farmacologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia
6.
Diabetes Care ; 47(7): 1194-1201, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38787410

RESUMO

OBJECTIVE: To examine the relationship between gestational glucose intolerance (GGI) and neonatal hypoglycemia. RESEARCH DESIGN AND METHODS: This was a secondary analysis of 8,262 mother-infant dyads, with delivery at two hospitals between 2014 and 2023. We categorized maternal glycemic status as normal glucose tolerance (NGT), GGI, or gestational diabetes mellitus (GDM). We defined NGT according to a normal glucose load test result, GGI according to an abnormal glucose load test result with zero (GGI-0) or one (GGI-1) abnormal value on the 100-g oral glucose tolerance test, and GDM according to an abnormal glucose load test result with two or more abnormal values on the glucose tolerance test. Neonatal hypoglycemia was defined according to blood glucose <45 mg/dL or ICD-9 or ICD-10 diagnosis of neonatal hypoglycemia. We used logistic regression analysis to determine associations between maternal glucose tolerance category and neonatal hypoglycemia and conducted a sensitivity analysis using Δ-adjusted multiple imputation, assuming for unscreened infants a rate of neonatal hypoglycemia as high as 33%. RESULTS: Of infants, 12% had neonatal hypoglycemia. In adjusted models, infants born to mothers with GGI-0 had 1.28 (95% 1.12, 1.65), GGI-1 1.58 (95% CI 1.11, 2.25), and GDM 4.90 (95% CI 3.81, 6.29) times higher odds of neonatal hypoglycemia in comparison with infants born to mothers with NGT. Associations in sensitivity analyses were consistent with the primary analysis. CONCLUSIONS: GGI is associated with increased risk of neonatal hypoglycemia. Future research should include examination of these associations in a cohort with more complete neonatal blood glucose ascertainment and determination of the clinical significance of these findings on long-term child health.


Assuntos
Diabetes Gestacional , Intolerância à Glucose , Hipoglicemia , Humanos , Feminino , Hipoglicemia/epidemiologia , Hipoglicemia/diagnóstico , Hipoglicemia/sangue , Recém-Nascido , Diabetes Gestacional/sangue , Gravidez , Adulto , Teste de Tolerância a Glucose , Masculino , Glicemia/análise , Glicemia/metabolismo , Fatores de Risco , Mães
7.
Nat Chem Biol ; 7(9): 610-6, 2011 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-21765405

RESUMO

Translation initiation plays a critical role in cellular homeostasis, proliferation, differentiation and malignant transformation. Consistently, increasing the abundance of the eIF2-GTP-tRNA(i)(Met) translation initiation complex transforms normal cells and contributes to cancer initiation and the severity of some anemias. The chemical modifiers of the eIF2-GTP-tRNA(i)(Met) ternary complex are therefore invaluable tools for studying its role in the pathobiology of human disorders and for determining whether this complex can be pharmacologically targeted for therapeutic purposes. Using a cell-based assay, we identified N,N'-diarylureas as unique inhibitors of ternary complex accumulation. Direct functional-genetic and biochemical evidence demonstrated that the N,N'-diarylureas activate heme-regulated inhibitor kinase, thereby phosphorylating eIF2α and reducing the abundance of the ternary complex. Using tumor cell proliferation in vitro and tumor growth in vivo as paradigms, we demonstrate that N,N'-diarylureas are potent and specific tools for studying the role of eIF2-GTP-tRNA(i)(Met) ternary complex in the pathobiology of human disorders.


Assuntos
Antineoplásicos/química , Iniciação Traducional da Cadeia Peptídica/efeitos dos fármacos , Ureia/análogos & derivados , eIF-2 Quinase/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto , eIF-2 Quinase/química , eIF-2 Quinase/genética
8.
Muscle Nerve ; 47(1): 33-40, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23042232

RESUMO

INTRODUCTION: Intrinsic mouse complement regulators influence the severity of passively induced experimental acquired myasthenia gravis (EAMG). To assess the potential influence of CD59b in the absence of CD59a background, we used the mCD59ab(-/-) mouse model to re-evaluate mCD59 in protecting the neuromuscular junction (NMJ). METHODS: EAMG was induced with monoclonal antibody to the acetylcholine receptor (AChR) in Daf1(-/-) , CD59ab(-/-) , Daf1(-/-) CD59ab(-/-) , and wild-type C57Bl/6 mice. Animals were monitored throughout the experiment. Diaphragms were analyzed for NMJ injury. RESULTS: Daf1(-/-) CD59ab(-/-) mice required euthanasia 24 hours after disease induction because of severe weakness. Histological assessment demonstrated reduced AChR density, simplification of synaptic folds, and disrupted mitochondria. CD59ab-deficient mice demonstrated mild weakness and reduction in weight after 24 hours. In contrast, Daf1(-/-) had more severe weakness at 60 hours. The NMJ of EAMG-induced Daf1(-/-) and CD59ab(-/-) mice demonstrated similar AChR density. CONCLUSION: NMJs of CD59 and DAF mice are protected from complement-mediated injury of passive EAMG.


Assuntos
Antígenos CD59/imunologia , Membrana Celular/imunologia , Proteínas do Sistema Complemento/imunologia , Miastenia Gravis Autoimune Experimental/imunologia , Junção Neuromuscular/imunologia , Animais , Membrana Celular/patologia , Camundongos , Camundongos Transgênicos , Miastenia Gravis Autoimune Experimental/patologia , Junção Neuromuscular/patologia , Receptores Colinérgicos/imunologia
9.
Am J Hematol ; 88(8): 670-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23670858

RESUMO

Increasing evidence links the complement system with complications of human diabetes. The complement regulatory protein CD59, an inhibitor of formation of membrane attack complex (MAC), is inhibited by hyperglycemia-induced glycation fostering increased deposition of MAC, a major effector of complement-mediated tissue damage. CD59, an ubiquitous GPI-anchored membrane protein, is shed from cell membranes by phospholipases generating a soluble form present in blood and urine. We established an enzyme-linked immunosorbent assay (ELISA) to measure serum/plasma glycated human CD59 (hCD59) (GCD59) and evaluated its potential as a diabetes biomarker. We used a synthetic peptide strategy to generate (a) a mouse monoclonal antibody to capture hCD59, (b) a rabbit monoclonal antibody to detect GCD59, and (c) a GCD59 surrogate for assay standardization. ELISA conditions were optimized for precision, reproducibility, and clinical sensitivity. The clinical utility of the assay was initially evaluated in 24 subjects with or without diabetes and further validated in a study that included 100 subjects with and 90 subjects without a diagnosis of diabetes. GCD59 (a) was significantly higher in individuals with than in individual without diabetes, (b) was independently associated with HbA1c, and (c) identified individuals with diabetes with high specificity and sensitivity. We report the development and standardization of a novel, sensitive, and specific ELISA for measuring GCD59 in blood. The assay distinguished individuals with diabetes from those without, and showed strong correlation between GCD59 and HbA1c. Because GCD59 likely contributes to the pathogenesis of diabetes complications, measurement of blood levels of GCD59 may be useful in the diagnosis and management of diabetes.


Assuntos
Antígenos CD59/sangue , Diabetes Mellitus Tipo 2/sangue , Adolescente , Adulto , Animais , Anticorpos Monoclonais Murinos/química , Anticorpos Monoclonais Murinos/imunologia , Biomarcadores/sangue , Biomarcadores/química , Antígenos CD59/química , Antígenos CD59/imunologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Hemoglobinas Glicadas/imunologia , Hemoglobinas Glicadas/metabolismo , Glicosilação , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Ratos , Sensibilidade e Especificidade
10.
Acta Diabetol ; 60(2): 211-223, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36309618

RESUMO

AIM: Even though most pregnancies are uneventful, occasionally complications do occur. Gestational diabetes is linked to an increased risk of adverse pregnancy outcomes. Early identification of women at risk of experiencing adverse outcomes, ideally through a single blood test, would facilitate early intervention. Plasma glycated CD59 (pGCD59) is an emerging biomarker which has shown promise in identifying hyperglycaemia during pregnancy and has been associated with the risk of delivering an LGA infant. The aim of this study was to explore the ability of the first- and second-trimester pGCD59 to predict adverse pregnancy outcomes. METHODS: This was a prospective study of 378 pregnant women. Samples for pGCD59 were taken at the first antenatal visit and at the time of the 2 h 75 g OGTT (24-28 weeks of gestation). Adjusted receiver operating characteristic curves were used to evaluate the ability of pGCD59 to predict maternal and neonatal outcomes. RESULTS: First-trimester pGCD59 levels were higher in women with gestational diabetes who delivered a macrosomic infant (4.2 ± 0.7 vs. 3.5 ± 1.0 SPU, p < 0.01) or an LGA infant (4.3 ± 0.3 vs. 3.6 ± 1.0 SPU, p = 0.01) compared to women with GDM that did not experience these outcomes. Second-trimester pGCD59 levels were higher in women that developed polyhydramnios (2.9 ± 0.4 vs. 2.5 ± 1.1 SPU, p = 0.03). First- and second-trimester pGCD59 predicted pregnancy-induced hypertension with good accuracy (AUC:0.85, 95%CI:0.78-0.91; AUC: 0.80, 95%CI: 0.73-0.88, respectively) and neonatal hypoglycaemia with fair to good accuracy (AUC:0.77, 95%CI: 0.54-0.99, AUC:0.81, 95%CI:0.62-0.99). CONCLUSIONS: This study has shown that pGCD59 has the potential to predict adverse pregnancy outcomes. Prospective studies with a larger number of cases are necessary to fully explore and validate the potential of this emerging biomarker in predicting adverse pregnancy outcomes.


Assuntos
Diabetes Gestacional , Recém-Nascido , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiologia , Estudos Prospectivos , Gestantes , Irlanda , Resultado da Gravidez/epidemiologia , Peso ao Nascer , Biomarcadores
11.
Blood ; 116(9): 1613-22, 2010 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-20511540

RESUMO

Pulmonary arterial hypertension (PAH) is suspected to be a strong mortality determinant of hemolytic disorders. However, direct contribution of acute intravascular hemolysis to fatal PAH has not been investigated. The roles of nitric oxide (NO) insufficiency and platelet activation in hemolysis-associated fatal PAH have been suspected but not been experimentally studied. We recently generated a unique intravascular hemolysis mouse model in which the membrane toxin, intermedilysin (ILY), exclusively lyses the erythrocytes of transgenically expressing human CD59 mice (ThCD59(RBC)), thereby inducing ILY-dose-dependent massive hemolysis. Using this murine hemolysis model, we found that the acute increase in pulmonary arterial pressure leading to right ventricle failure caused sudden death. Reduced NO bioavailability and massive platelet activation/aggregation leading to the formation of massive thrombosis specifically in the pulmonary microvasculature played the critical roles in pathogenesis of acute hemolysis-associated fatal PAH. Therapeutic interventions enhancing NO bioactivity or inhibiting platelet activation prevented sudden death or prolonged survival time via the suppression of the acute increase in pulmonary arterial pressure and improvement of right ventricle function. These findings further highlight the importance of the inhibition of platelet activation and the enhancement of NO bioavailability for the treatment and prevention of hemolysis-associated (fatal) PAH.


Assuntos
Modelos Animais de Doenças , Hemólise , Hipertensão Pulmonar/mortalidade , Hipertensão Pulmonar/patologia , Óxido Nítrico/farmacocinética , Ativação Plaquetária , Artéria Pulmonar/fisiopatologia , Animais , Bacteriocinas/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Antígenos CD59/fisiologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/patologia , Fibrinolíticos/farmacologia , Humanos , Hipertensão Pulmonar/complicações , Camundongos , Camundongos Transgênicos , Agregação Plaquetária , Taxa de Sobrevida , Distribuição Tecidual
12.
Bioorg Med Chem Lett ; 22(1): 402-9, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22153346

RESUMO

Symmetrical N,N'-diarylureas: 1,3-bis(3,4-dichlorophenyl)-, 1,3-bis[4-chloro-3-(trifluoromethyl)phenyl]- and 1,3-bis[3,5-bis(trifluoromethyl)phenyl]urea, were identified as potent activators of the eIF2α kinase heme regulated inhibitor. They reduce the abundance of the eIF2·GTP·tRNA(i)(Met) ternary complex and inhibit cancer cell proliferation. An optimization process was undertaken to improve their solubility while preserving their biological activity. Non-symmetrical hybrid ureas were generated by combining one of the hydrophobic phenyl moieties present in the symmetrical ureas with the polar 3-hydroxy-tolyl moiety. O-alkylation of the later added potentially solubilizing charge bearing groups. The new non-symmetrical N,N'-diarylureas were characterized by ternary complex reporter gene and cell proliferation assays, demonstrating good bioactivities. A representative sample of these compounds potently induced phosphorylation of eIF2α and expression of CHOP at the protein and mRNA levels. These inhibitors of translation initiation may become leads for the development of potent, non-toxic, and target specific anti-cancer agents.


Assuntos
Antineoplásicos/farmacologia , Química Farmacêutica/métodos , Animais , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos , Fator de Iniciação 2 em Eucariotos/química , Genes Reporter , Humanos , Técnicas In Vitro , Concentração Inibidora 50 , Camundongos , Modelos Químicos , Fosforilação , RNA Mensageiro/metabolismo , RNA de Transferência de Metionina/química , Relação Estrutura-Atividade , Fator de Transcrição CHOP/química , Transfecção , Ureia/química
13.
J Immunol ; 184(1): 359-68, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19955519

RESUMO

Many pathogenic enveloped viruses, including HIV-1, escape complement-mediated virolysis by incorporating host cell regulators of complement activation into their own viral envelope. The presence of complement regulators including CD59 on the external surface of the viral envelope confers resistance to complement-mediated virolysis, which may explain why human pathogenic viruses such as HIV-1 are not neutralized by complement in human fluids, even in the presence of high Ab titers against the viral surface proteins. In this study, we report the development of a recombinant form of the fourth domain of the bacterial toxin intermedilysin (the recombinant domain 4 of intermedilysin [rILYd4]), a 114 aa protein that inhibits human CD59 function with high affinity and specificity. In the presence of rILYd4, HIV-1 virions derived from either cell lines or peripheral blood mononuclear cells of HIV-1-infected patients became highly sensitive to complement-mediated lysis activated by either anti-HIV-1 gp120 Abs or by viral infection-induced Abs present in the plasma of HIV-1-infected individuals. We also demonstrated that rILYd4 together with serum or plasma from HIV-1-infected patients as a source of anti-HIV-1 Abs and complement did not mediate complement-mediated lysis of either erythrocytes or peripheral blood mononuclear cells. These results indicate that rILYd4 may represent a novel therapeutic agent against HIV-1/AIDS.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Bacteriocinas/imunologia , Antígenos CD59/metabolismo , Proteínas do Sistema Complemento/imunologia , HIV-1/imunologia , Bacteriocinas/farmacologia , Antígenos CD59/imunologia , Ativação do Complemento/imunologia , Citometria de Fluxo , Humanos , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia
14.
BMJ Open ; 12(4): e054773, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35443950

RESUMO

INTRODUCTION: The significant maternal and neonatal outcomes of gestational diabetes mellitus (GDM) make it a major public health concern. Mothers with GDM are at greater risk of pregnancy complications and their offspring are at higher risk of diabetes and obesity. Currently, GDM is diagnosed with glucose load methods which are time-consuming and inconvenient to administer more than once during pregnancy; for this reason, there is a recognised need for a more accurate and simpler test for GDM. Previous studies indicate that plasma-glycated CD59 (pGCD59) is a novel biomarker for GDM. We present here the protocol of a prospective cohort study designed to (1) determine the accuracy of pGCD59 as an early, first trimester predictor of GDM and gestational impaired glucose tolerance and (2) assess the associations between pGCD59 levels and adverse maternal and neonatal outcomes. METHODS AND ANALYSIS: We will obtain discarded plasma samples from pregnant women at two time points: first prenatal visit (usually <14 weeks gestation) and gestational weeks 24-28. A study-specific medical record abstraction tool will be used to obtain relevant maternal and neonatal clinical data from the EPIC clinical database. The prevalence of GDM will be determined using standard of care glucose load test results. We will determine the sensitivity and specificity of pGCD59 to predict the diagnosis of GDM and gestational impaired glucose tolerance, as well as the associations between levels of pGCD59 and the prevalence of maternal and neonatal outcomes. ETHICS AND DISSEMINATION: This study has been approved by the Mass General Brigham Institutional Review Board (protocol 2011P002254). The results of this study will be presented at international meetings and disseminated in peer-reviewed journals.


Assuntos
Diabetes Gestacional , Intolerância à Glucose , Biomarcadores , Glicemia , Antígenos CD59 , Diabetes Gestacional/epidemiologia , Feminino , Glucose , Humanos , Recém-Nascido , Gravidez , Estudos Prospectivos
15.
J Clin Med ; 11(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35807179

RESUMO

The aim of this study was to evaluate the ability of second trimester plasma glycated CD59 (pGCD59), a novel biomarker, to predict the results of the 2 h 75 g oral glucose tolerance test at 24−28 weeks of gestation, employing the 2013 World Health Organisation criteria. This was a prospective study of 378 pregnant women. The ability of pGCD59 to predict gestational diabetes (GDM) was assessed using adjusted ROC curves for maternal age, BMI, maternal ethnicity, parity, previous GDM, and family history of diabetes. The pGCD59 levels were significantly higher in women with GDM compared to women with normal glucose tolerance (p = 0.003). The pGCD59 generated an adjusted AUC for identifying GDM cases of 0.65 (95%CI: 0.58−0.71, p < 0.001). The pGCD59 predicted GDM status diagnosed by a fasting glucose value of 5.1 mmol/L with an adjusted AUC of 0.74 (95%CI: 0.65−0.81, p < 0.001). Analysis of BMI subgroups determined that pGCD59 generated the highest AUC in the 35 kg/m2 ≤ BMI < 40 kg/m2 (AUC: 0.84 95%CI: 0.69−0.98) and BMI ≥ 40 kg/m2 (AUC: 0.96 95%CI: 0.86−0.99) categories. This study found that second trimester pGCD59 is a fair predictor of GDM status diagnosed by elevated fasting glucose independent of BMI and an excellent predictor of GDM in subjects with a very high BMI.

16.
Diabetes Res Clin Pract ; 190: 110023, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35907507

RESUMO

AIMS: To evaluate the ability of first trimester plasma glycated CD59 (pGCD59) to predict gestational diabetes mellitus (GDM) at 24-28 weeks of gestation. METHODS: Prospectively, in 378 pregnant women, GDM was diagnosed using the one step 2 h 75 g oral glucose tolerance test adjudicated by the World Health Organisation (WHO) 2013 criteria. The ability of pGCD59 to predict GDM was assessed using receiver operating characteristic (ROC) curves adjusted for maternal age, body mass index (BMI), maternal ethnicity, parity, previous GDM, family history of diabetes mellitus and week of gestation at time of pGCD59 sampling. RESULTS: pGCD59 generated an adjusted area under the curve (AUC) of (a) 0.63 (95 %CI:0.56-0.70, p < 0.001) for predicting GDM, and (b) 0.71 (95 %CI:0.62-0.79, p < 0.001 for GDM diagnosed with a fasting plasma glucose (FPG) ≥ 5.1 mmol/L. Sensitivity analysis of BMI subgroups showed that pGCD59 generated the highest AUC in the 35 kg/m2 ≤ BMI < 40 kg/m2 (AUC:0.85, 95 %CI:0.70-0.98) and BMI ≥ 40 kg/m2 (AUC:0.88, 95 %CI:0.63-0.99) categories. CONCLUSIONS: Early in pregnancy, pGCD59 may be a good predictor of GDM in women with a high BMI and a fair predictor of GDM diagnosed by an elevated FPG independent of BMI.


Assuntos
Diabetes Gestacional , Glicemia , Índice de Massa Corporal , Antígenos CD59 , Diabetes Gestacional/diagnóstico , Feminino , Humanos , Irlanda , Gravidez , Primeiro Trimestre da Gravidez , Gestantes , Estudos Prospectivos
17.
J Clin Endocrinol Metab ; 107(11): e4311-e4319, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36054347

RESUMO

CONTEXT: Neonatal hypoglycaemia (NH) is the most common metabolic problem in infants born of mothers with gestational diabetes. Plasma glycated CD59 (pGCD59) is an emerging biomarker that has shown potential in identifying women at risk of developing gestational diabetes. The aim of this study was to assess the association between early maternal levels of pGCD59 and NH. OBJECTIVE: The aim of this study was to assess the association between early pregnancy maternal levels of plasma glycated CD59 (pGCD59) and neonatal hypoglycemia (NH). METHODS: This is an observational study of pregnant women with a prepregnancy body mass index (BMI) greater than or equal to 29 screened for eligibility to participate in the Vitamin D and Lifestyle Intervention for Gestational Diabetes (DALI) trial. This analysis included 399 pregnancies. Levels of pGCD59 were measured in fasting maternal samples taken at the time of a 75-g, 2-hour oral glucose tolerance test performed in early pregnancy (< 20 weeks). NH, the study outcome, was defined as a heel-prick capillary glucose level of less than 2.6 mmol/L within 48 hours of delivery. RESULTS: We identified 30 infants with NH. Maternal levels of pGCD59 in early pregnancy were positively associated with the prevalence of NH (one-way analysis of variance, P < .001). The odds of NH were higher in infants from mothers in tertile 3 of pGCD59 levels compared to those from mothers in tertile 1 (odds ratio [OR]: 2.41; 95% CI, 1.03-5.63). However, this was attenuated when adjusted for maternal BMI (OR: 2.28; 95% CI, 0.96-5.43). The cross-validated area under the curve (AUC) was 0.64 (95% CI, 0.54-0.74), and adjusted for maternal BMI, age, and ethnicity, the AUC was 0.70 (95% CI, 0.56-0.78). CONCLUSION: Although pGCD59 levels in early pregnancy in women with BMI greater than or equal to 29 are associated with NH, our results indicate that this biomarker by itself is only a fair predictor of NH.


Assuntos
Diabetes Gestacional , Doenças Fetais , Hipoglicemia , Doenças do Recém-Nascido , Recém-Nascido , Lactente , Feminino , Gravidez , Humanos , Diabetes Gestacional/epidemiologia , Glicemia/metabolismo , Teste de Tolerância a Glucose , Hipoglicemia/epidemiologia , Biomarcadores/análise
18.
Circulation ; 121(11): 1338-46, 2010 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-20212283

RESUMO

BACKGROUND: Complement system, an innate immunity, has been well documented to play a critical role in many inflammatory diseases. However, the role of complement in the pathogenesis of abdominal aortic aneurysm, which is considered an immune and inflammatory disease, remains obscure. METHODS AND RESULTS: Here, we evaluated the pathogenic roles of complement membrane attack complex and CD59, a key regulator that inhibits the membrane attack complex, in the development of abdominal aortic aneurysm. We demonstrated that in the angiotensin II-induced abdominal aortic aneurysm model, deficiency of the membrane attack complex regulator CD59 in ApoE-null mice (mCd59ab(-/-)/ApoE(-/-)) accelerated the disease development, whereas transgenic overexpression of human CD59 (hCD59(ICAM-2+/-)/ApoE(-/-)) in this model attenuated the progression of abdominal aortic aneurysm. The severity of aneurysm among these 3 groups positively correlates with C9 deposition, and/or the activities of MMP2 and MMP9, and/or the levels of phosphorylated c-Jun, c-Fos, IKK-alpha/beta, and p65. Furthermore, we demonstrated that the membrane attack complex directly induced gene expression of matrix metalloproteinase-2 and -9 in vitro, which required activation of the activator protein-1 and nuclear factor-kappaB signaling pathways. CONCLUSIONS: Together, these results defined the protective role of CD59 and shed light on the important pathogenic role of the membrane attack complex in abdominal aortic aneurysm.


Assuntos
Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/prevenção & controle , Antígenos CD59/metabolismo , Proteínas do Sistema Complemento/metabolismo , Angiotensina II/efeitos adversos , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Antígenos CD59/genética , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Modelos Animais , NF-kappa B/metabolismo , Transdução de Sinais , Fator de Transcrição AP-1/metabolismo
19.
Circ Res ; 104(4): 550-8, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19131645

RESUMO

Complement is a central effector system within the immune system and is implicated in a range of inflammatory disorders. CD59 is a key regulator of complement membrane attack complex (MAC) assembly. The atherogenic role of terminal complement has long been suspected but is still unclear. Here, we demonstrate that among mice deficient in apolipoprotein (Apo)E, the additional loss of murine CD59 (mCd59ab(-/-)/ApoE(-/-)) accelerated advanced atherosclerosis featuring occlusive coronary atherosclerosis, vulnerable plaque, and premature death and that these effect could be attenuated by overexpression of human CD59 in the endothelium. Complement inhibition using a neutralizing anti-mouse C5 antibody attenuated atherosclerosis in mCd59ab(-/-)/ApoE(-/-) mice. Furthermore, MAC mediated endothelial damage and promoted foam cell formation. These combined results highlight the atherogenic role of MAC and the atheroprotective role of CD59 and suggest that inhibition of MAC formation may provide a therapeutic approach for the treatment of atherosclerosis.


Assuntos
Aterosclerose/prevenção & controle , Antígenos CD59/metabolismo , Ativação do Complemento , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/imunologia , Aterosclerose/patologia , Antígenos CD59/genética , Linhagem Celular , Complemento C5/imunologia , Complemento C9/imunologia , Doença da Artéria Coronariana/imunologia , Doença da Artéria Coronariana/prevenção & controle , Gorduras na Dieta/administração & dosagem , Modelos Animais de Doenças , Progressão da Doença , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Células Espumosas/imunologia , Células Espumosas/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Coelhos , Índice de Gravidade de Doença , Fatores de Tempo
20.
Eur J Endocrinol ; 185(5): 755-763, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34524975

RESUMO

AIM: To assess whether in women with gestational diabetes mellitus (GDM), postpartum plasma glycated CD59 (pGCD59) levels predict conversion to glucose intolerance diagnosed with an oral glucose tolerance test (OGTT). METHODS: Blood levels of pGCD59 were measured in a case-control study of 105 women with GDM who underwent a 75 g OGTT 3 months postpartum. The 35 postpartum glucose intolerant cases were individually matched for age, BMI, ethnic origin, and parity with 70 women with GDM but normal postpartum OGTT (controls). The GDM cohort (105) was also matched with 105 normal glucose tolerant women during pregnancy. pGCD59 was measured by ELISA in standard peptide units (SPU). RESULTS: Mean pGCD59 postpartum was significantly higher in cases than in controls (1.5 ± 0.6 SPU vs 1.0 ± 0.6 SPU, P < 0.001). The area under the receiving operating characteristic curve (AUC) in cases vs controls was 0.72 (95% CI: 0.62-0.83) for postpartum pGCD59 and 0.50 (95% CI: 0.36-0.61) for postpartum HbA1c. A 0.5-unit increase in postpartum pGCD59 was associated with an odds ratio (OR) of 3.3 (95% CI: 1.82-6.16, P < 0.001) for glucose intolerance postpartum. A pGCD59 cut-off postpartum of 0.9 SPU had a sensitivity of 85.7% (95% CI: 69.7-95.2%), specificity of 47.8% (95% CI: 35.6-60.2%), positive predictive value of 45.4% (95% CI: 33.1-58.2%), and negative predictive value of 86.8% (95% CI: 71.9-95.6%). pGCD59 in pregnancy was a poor predictor for glucose intolerance postpartum (AUC of 0.61 (95% CI: 0.50-0.72)). CONCLUSION: pGCD59 might identify women at low risk for glucose intolerance postpartum and could help to avoid an OGTT.


Assuntos
Antígenos CD59/análise , Diabetes Gestacional/sangue , Intolerância à Glucose/sangue , Período Pós-Parto/sangue , Adulto , Área Sob a Curva , Glicemia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Intolerância à Glucose/etiologia , Hemoglobinas Glicadas/análise , Humanos , Paridade , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
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