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1.
Thromb Haemost ; 119(7): 1171-1181, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129911

RESUMO

BACKGROUND: Oral P2Y12 inhibitors take more than 2 hours to achieve full effect in healthy subjects and this action is further delayed in patients with acute myocardial infarction. Intravenous P2Y12 inhibition might lead to more timely and potent anti-platelet effect in the context of emergency primary angioplasty, improving myocardial recovery. OBJECTIVES: This article compares the efficacy of intravenous cangrelor versus ticagrelor in a ST-elevation myocardial infarction (STEMI) population treated with primary percutaneous coronary intervention (PPCI). MATERIALS AND METHODS: In an open-label, prospective, randomized controlled trial, 100 subjects with STEMI were assigned 1:1 to intravenous cangrelor or oral ticagrelor. The co-primary endpoints were platelet P2Y12 inhibition at infarct vessel balloon inflation time, 4 and 24 hours. Secondary endpoints included indices of coronary microcirculatory function: index of microvascular resistance (IMR), initial infarct size (troponin at 24 hours) and final infarct size at 12 weeks (cardiac magnetic resonance). Secondary endpoints included indices of coronary microcirculatory function (index of microvascular resistance [IMR]), initial infarct size (troponin at 24 hours), final infarct size at 12 weeks (cardiac magnetic resonance), corrected thrombolysis in myocardial infarction (TIMI) frame count, TIMI flow grade, myocardial perfusion grade, and ST-segment resolution (ClinicalTrials.gov NCT02733341). RESULTS: P2Y12 inhibition at first balloon inflation time was significantly greater in cangrelor-treated patients (cangrelor P2Y12 reaction unit [PRU] 145.2 ± 50.6 vs. ticagrelor 248.3 ± 55.1). There was no difference in mean PRU at 4 and 24 to 36 hours post-dosing. IMR, final infarct size, angiographic and electrocardiographic measures of reperfusion were all similar between groups. CONCLUSION: Cangrelor produces more potent P2Y12 inhibition at the time of first coronary balloon inflation time compared with ticagrelor. Despite this enhanced P2Y12 inhibition, coronary microvascular function and final infarct size did not differ between groups.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Plaquetas/fisiologia , Vasos Sanguíneos/patologia , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/metabolismo , Ticagrelor/uso terapêutico , Monofosfato de Adenosina/uso terapêutico , Idoso , Plaquetas/efeitos dos fármacos , Vasos Sanguíneos/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Masculino , Microcirculação/efeitos dos fármacos , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Infarto do Miocárdio/cirurgia , Miocárdio/patologia , Intervenção Coronária Percutânea , Ativação Plaquetária , Testes de Função Plaquetária , Receptores Purinérgicos P2Y12/metabolismo , Fluxo Sanguíneo Regional/efeitos dos fármacos
2.
Sci Rep ; 8(1): 1216, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29352147

RESUMO

The environment for embryo implantation and fetal growth and development is affected by maternal nutritional, metabolic and health status. The aim of this prospective, cohort study was to test whether plasma metabolic and inflammatory biomarkers can predict pregnancy resulting from in vitro fertilisation (IVF). Women with a natural menstrual cycle undergoing frozen embryo transfer (FET) were recruited and fasting baseline blood samples were collected a mean of 3.4 days prior to the luteinising hormone (LH) surge and a non-fasting blood sample was taken on the day of FET. Ongoing pregnancy was defined by positive fetal heartbeat on ultrasound scan at day 45 post LH surge. Thirty-six pregnancies resulted from FET in 143 women. In an overall stepwise multivariable analysis, erythrocyte saturated to unsaturated fatty acid ratio was positively associated with ongoing pregnancy. A similar model incorporating day of FET covariates found that erythrocyte saturated to unsaturated fatty acid ratio, erythrocyte fatty acid average chain length and plasma log-triglycerides predicted ongoing pregnancy. In conclusion, a higher peri-conceptional saturated to unsaturated fatty acid ratio predicted ongoing pregnancy after natural cycle frozen embryo transfer and may reflect a maternal nutritional status that facilitates pregnancy success in this assisted conception scenario.


Assuntos
Transferência Embrionária , Eritrócitos/metabolismo , Ácidos Graxos/metabolismo , Ciclo Menstrual , Taxa de Gravidez , Biomarcadores , Implantação do Embrião , Metabolismo Energético , Feminino , Fertilização , Fertilização in vitro , Humanos , Mediadores da Inflamação , Razão de Chances , Gravidez , Prognóstico
4.
Nucleic Acid Ther ; 27(4): 209-220, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28448194

RESUMO

Phosphorothioate (PS) modified antisense oligonucleotides (ASOs) have progressed rapidly in the clinic for treating a variety of disease indications. We previously demonstrated that the activity of PS ASOs in the liver can be enhanced by co-infusion of an excipient oligonucleotide (EON). It was posited that the EON saturates a nonproductive uptake pathway(s) thereby permitting accumulation of the PS ASO in a productive tissue compartment. In this report, we measured PS ASO activity following administration by bolus, infusion or co-fusion with EON within hepatocytes and nonparenchymal cells (NPCs), of the liver. This revealed that while ASOs accumulate preferentially in NPCs, they are intrinsically more active in hepatocytes. Furthermore, we show that the EON enhances ASO potency when infused up to 72 h before or after administration of the active ASO suggesting that the EON can saturate and displace the ASO from nonproductive to productive compartments. Physical presence of the EON in tissues was required for optimal potentiation suggesting that there is a dynamic distribution of the ASO and EON between the compartments. Lastly, using a candidate approach, we confirmed Stabilin-2 as a molecular pathway for ASO uptake in sinusoidal endothelial cells and the ASGR as a pathway for ASO uptake into hepatocytes in the liver.


Assuntos
Excipientes/farmacocinética , Fígado/metabolismo , Oligonucleotídeos Antissenso/farmacocinética , Oligonucleotídeos Fosforotioatos/farmacocinética , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Células Endoteliais/metabolismo , Excipientes/administração & dosagem , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/citologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Fosforotioatos/administração & dosagem , Distribuição Tecidual
5.
Bioorg Med Chem Lett ; 26(15): 3690-3, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27268307

RESUMO

Antisense oligonucleotides (ASOs) conjugated to trivalent GalNAc ligands show 10-fold enhanced potency for suppressing gene targets expressed in hepatocytes. Trivalent GalNAc is a high affinity ligand for the asialoglycoprotein receptor (ASGR)-a C-type lectin expressed almost exclusively on hepatocytes in the liver. In this communication, we show that conjugation of two and even one GalNAc sugar to single stranded chemically modified ASOs can enhance potency 5-10 fold in mice. Evaluation of the mono- and di-GalNAc ASO conjugates in an ASGR binding assay suggested that chemical features of the ASO enhance binding to the receptor and provide a rationale for the enhanced potency.


Assuntos
Acetilgalactosamina/farmacologia , Receptor de Asialoglicoproteína/metabolismo , Hepatócitos/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Acetilgalactosamina/administração & dosagem , Acetilgalactosamina/química , Animais , Relação Dose-Resposta a Droga , Hepatócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Conformação Molecular , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/química , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/metabolismo , Receptores Depuradores Classe B/antagonistas & inibidores , Receptores Depuradores Classe B/metabolismo , Relação Estrutura-Atividade
6.
Nucleic Acids Res ; 44(11): 5299-312, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27131367

RESUMO

Viable constitutive and tamoxifen inducible liver-specific RNase H1 knockout mice that expressed no RNase H1 activity in hepatocytes showed increased R-loop levels and reduced mitochondrial encoded DNA and mRNA levels, suggesting impaired mitochondrial R-loop processing, transcription and mitochondrial DNA replication. These changes resulted in mitochondrial dysfunction with marked changes in mitochondrial fusion, fission, morphology and transcriptional changes reflective of mitochondrial damage and stress. Liver degeneration ensued, as indicated by apoptosis, fibrosis and increased transaminase levels. Antisense oligonucleotides (ASOs) designed to serve as substrates for RNase H1 were inactive in the hepatocytes from the RNase H1 knockout mice and in vivo, demonstrating that RNase H1 is necessary for the activity of DNA-like ASOs. During liver regeneration, a clone of hepatocytes that expressed RNase H1 developed and partially restored mitochondrial and liver function.


Assuntos
Fígado/metabolismo , Mitocôndrias Hepáticas/genética , Mitocôndrias Hepáticas/metabolismo , Conformação de Ácido Nucleico , RNA/metabolismo , Ribonuclease H/deficiência , Animais , Análise por Conglomerados , Replicação do DNA , DNA Mitocondrial , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Camundongos , Camundongos Knockout , Especificidade de Órgãos/genética , RNA/química , RNA/genética , Ribonuclease H/metabolismo , Especificidade por Substrato
7.
Bioorg Med Chem Lett ; 26(12): 2817-2820, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27161280

RESUMO

Chemical modifications are essential to improve metabolic stability and pharmacokinetic properties of siRNA to enable their systemic delivery. We investigated the effect of combing the phosphorothioate (PS) modification with metabolically stable phosphate analog (E)-5'-vinylphosphonate and GalNAc cluster conjugation on the activity of fully 2'-modified siRNA in cell culture and mice. Our data suggest that integrating multiple chemical approaches in one siRNA molecule improved potency 5-10 fold and provide a roadmap for developing more efficient siRNA drugs.


Assuntos
Acetilgalactosamina/metabolismo , Organofosfonatos/metabolismo , PTEN Fosfo-Hidrolase/antagonistas & inibidores , Fosfatos/metabolismo , RNA Interferente Pequeno/farmacologia , Compostos de Vinila/metabolismo , Acetilgalactosamina/química , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Organofosfonatos/química , PTEN Fosfo-Hidrolase/metabolismo , Fosfatos/química , RNA Interferente Pequeno/metabolismo , Relação Estrutura-Atividade , Compostos de Vinila/química
8.
J Med Chem ; 59(6): 2718-33, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26914862

RESUMO

The comprehensive structure-activity relationships of triantennary GalNAc conjugated ASOs for enhancing potency via ASGR mediated delivery to hepatocytes is reported. Seventeen GalNAc clusters were assembled from six distinct scaffolds and attached to ASOs. The resulting ASO conjugates were evaluated in ASGR binding assays, in primary hepatocytes, and in mice. Five structurally distinct GalNAc clusters were chosen for more extensive evaluation using ASOs targeting SRB-1, A1AT, FXI, TTR, and ApoC III mRNAs. GalNAc-ASO conjugates exhibited excellent potencies (ED50 0.5-2 mg/kg) for reducing the targeted mRNAs and proteins. This work culminated in the identification of a simplified tris-based GalNAc cluster (THA-GN3), which can be efficiently assembled using readily available starting materials and conjugated to ASOs using a solution phase conjugation strategy. GalNAc-ASO conjugates thus represent a viable approach for enhancing potency of ASO drugs in the clinic without adding significant complexity or cost to existing protocols for manufacturing oligonucleotide drugs.


Assuntos
Acetilgalactosamina/síntese química , Acetilgalactosamina/farmacologia , Hepatócitos/efeitos dos fármacos , Oligonucleotídeos Antissenso/síntese química , Oligonucleotídeos Antissenso/farmacologia , Animais , Apolipoproteína C-III/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Fator XI/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores Depuradores Classe B/biossíntese , Receptores Depuradores Classe B/genética , Relação Estrutura-Atividade
9.
Int J Behav Nutr Phys Act ; 12: 125, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26416606

RESUMO

BACKGROUND: Programs to change health behaviours have been identified as one way to reduce health inequalities experienced by disadvantaged groups. The objective of this study was to examine the effectiveness of a behaviour change programme to increase walking and reduce sedentary behaviour of adults with intellectual disabilities. METHODS: We used a cluster randomised controlled design and recruited participants over 18 years old and not regularly involved in physical activity from intellectual disabilities community-based organisations. Assessments were carried out blind to allocation. Clusters of participants were randomly allocated to the Walk Well program or a 12-week waiting list control. Walk Well consisted of three face-to-face physical activity consultations incorporating behaviour change techniques, written resources for participants and carers, and an individualised, structured walking programme. The primary outcome measured with accelerometers was change in mean step count per day between baseline and 12 weeks. Secondary outcomes included percentage time per day sedentary and in moderate-vigorous physical activity (MVPA), body mass index (BMI), and subjective well being. RESULTS: One hundred two participants in 50 clusters were randomised. 82 (80.4%) participants completed the primary outcome. 66.7% of participants lived in the most deprived quintile on the Scottish Index of Multiple Deprivation. At baseline, participants walked 4780 (standard deviation 2432) steps per day, spent 65.5% (standard deviation 10.9) of time sedentary and 59% percent had a body mass in the obesity range. After the walking programme, the difference between mean counts of the Walk Well and control group was 69.5 steps per day [95% confidence interval (CI) -1054 to 1193.3]. There were no significant between group differences in percentage time sedentary 1.6% (95% CI -2.984 to 6.102), percentage time in MVPA 0.3% (95% CI -0.7 to 1.3), BMI -0.2 kg/m(2) (95% CI -0.8 to 0.4) or subjective well-being 0.3 (95% CI -0.9 to 1.5). CONCLUSIONS: This is the first published trial of a walking program for adults with intellectual disabilities. Positively changing physical activity and sedentary behaviours may require more intensive programmes or upstream approaches to address the multiple social disadvantages experienced by adults with intellectual disabilities. Since participants spent the majority of their time sedentary, home-based programmes to reduce sitting time may be a viable health improvement approach. TRIAL REGISTRATION: Current Controlled Trials ISRCTN50494254.


Assuntos
Comportamentos Relacionados com a Saúde , Promoção da Saúde/métodos , Deficiência Intelectual/reabilitação , Avaliação de Programas e Projetos de Saúde , Caminhada/estatística & dados numéricos , Adulto , Índice de Massa Corporal , Análise por Conglomerados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Qualidade de Vida , Encaminhamento e Consulta
10.
Bioconjug Chem ; 26(8): 1451-5, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26011654

RESUMO

Conjugation of triantennary N-acetyl galactosamine (GalNAc) to oligonucleotide therapeutics results in marked improvement in potency for reducing gene targets expressed in hepatocytes. In this report we describe a robust and efficient solution-phase conjugation strategy to attach triantennary GalNAc clusters (mol. wt. ∼2000) activated as PFP (pentafluorophenyl) esters onto 5'-hexylamino modified antisense oligonucleotides (5'-HA ASOs, mol. wt. ∼8000 Da). The conjugation reaction is efficient and was used to prepare GalNAc conjugated ASOs from milligram to multigram scale. The solution phase method avoids loading of GalNAc clusters onto solid-support for automated synthesis and will facilitate evaluation of GalNAc clusters for structure activity relationship (SAR) studies. Furthermore, we show that transfer of the GalNAc cluster from the 3'-end of an ASO to the 5'-end results in improved potency in cells and animals.


Assuntos
Acetilgalactosamina/química , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Oligonucleotídeos Antissenso/síntese química , Oligonucleotídeos Antissenso/farmacologia , Animais , Células Cultivadas , Hepatócitos/citologia , Fígado/citologia , Camundongos , Camundongos Endogâmicos C57BL
11.
Eur Heart J ; 36(24): 1536-46, 2015 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-25802390

RESUMO

AIMS: The effect of statins on risk of heart failure (HF) hospitalization and HF death remains uncertain. We aimed to establish whether statins reduce major HF events. METHODS AND RESULTS: We searched Medline, EMBASE, and the Cochrane Central Register of Controlled Trials for randomized controlled endpoint statin trials from 1994 to 2014. Collaborating trialists provided unpublished data from adverse event reports. We included primary- and secondary-prevention statin trials with >1000 participants followed for >1 year. Outcomes consisted of first non-fatal HF hospitalization, HF death and a composite of first non-fatal HF hospitalization or HF death. HF events occurring <30 days after within-trial myocardial infarction (MI) were excluded. We calculated risk ratios (RR) with fixed-effects meta-analyses. In up to 17 trials with 132 538 participants conducted over 4.3 [weighted standard deviation (SD) 1.4] years, statin therapy reduced LDL-cholesterol by 0.97 mmol/L (weighted SD 0.38 mmol/L). Statins reduced the numbers of patients experiencing non-fatal HF hospitalization (1344/66 238 vs. 1498/66 330; RR 0.90, 95% confidence interval, CI 0.84-0.97) and the composite HF outcome (1234/57 734 vs. 1344/57 836; RR 0.92, 95% CI 0.85-0.99) but not HF death (213/57 734 vs. 220/57 836; RR 0.97, 95% CI 0.80-1.17). The effect of statins on first non-fatal HF hospitalization was similar whether this was preceded by MI (RR 0.87, 95% CI 0.68-1.11) or not (RR 0.91, 95% CI 0.84-0.98). CONCLUSION: In primary- and secondary-prevention trials, statins modestly reduced the risks of non-fatal HF hospitalization and a composite of non-fatal HF hospitalization and HF death with no demonstrable difference in risk reduction between those who suffered an MI or not.


Assuntos
Insuficiência Cardíaca/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Prevenção Secundária , Resultado do Tratamento
12.
Nucleic Acids Res ; 43(6): 2993-3011, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25753666

RESUMO

The ss-siRNA activity in vivo requires a metabolically stable 5'-phosphate analog. In this report we used crystal structure of the 5'-phosphate binding pocket of Ago-2 bound with guide strand to design and synthesize ss-siRNAs containing various 5'-phosphate analogs. Our results indicate that the electronic and spatial orientation of the 5'-phosphate analog was critical for ss-siRNA activity. Chemically modified ss-siRNA targeting human apoC III mRNA demonstrated good potency for inhibiting ApoC III mRNA and protein in transgenic mice. Moreover, ApoC III ss-siRNAs were able to reduce the triglyceride and LDL cholesterol in transgenic mice demonstrating pharmacological effect of ss-siRNA. Our study provides guidance to develop surrogate phosphate analog for ss-siRNA and demonstrates that ss-siRNA provides an alternative strategy for therapeutic gene silencing.


Assuntos
RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo , Animais , Apolipoproteína C-III/genética , Apolipoproteína C-III/metabolismo , Proteínas Argonautas/química , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Sequência de Bases , Sítios de Ligação , LDL-Colesterol/sangue , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Modelos Moleculares , Estrutura Molecular , Conformação de Ácido Nucleico , Fosfatos/química , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Triglicerídeos/sangue
13.
Nucleic Acids Res ; 42(22): 13456-68, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25398895

RESUMO

Bicyclic oxazaphospholidine monomers were used to prepare a series of phosphorothioate (PS)-modified gapmer antisense oligonucleotides (ASOs) with control of the chirality of each of the PS linkages within the 10-base gap. The stereoselectivity was determined to be 98% for each coupling. The objective of this work was to study how PS chirality influences biophysical and biological properties of the ASO including binding affinity (Tm), nuclease stability, activity in vitro and in vivo, RNase H activation and cleavage patterns (both human and E. coli) in a gapmer context. Compounds that had nine or more Sp-linkages in the gap were found to be poorly active in vitro, while compounds with uniform Rp-gaps exhibited activity very similar to that of the stereo-random parent ASOs. Conversely, when tested in vivo, the full Rp-gap compound was found to be quickly metabolized resulting in low activity. A total of 31 ASOs were prepared with control of the PS chirally of each linkage within the gap in an attempt to identify favorable Rp/Sp positions. We conclude that a mix of Rp and Sp is required to achieve a balance between good activity and nuclease stability.


Assuntos
Oligonucleotídeos Antissenso/química , Oligonucleotídeos Fosforotioatos/química , Animais , Células Cultivadas , Proteínas Fúngicas/metabolismo , Camundongos , Oligonucleotídeos Antissenso/síntese química , Oligonucleotídeos Antissenso/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Ribonuclease H/metabolismo , Endonucleases Específicas para DNA e RNA de Cadeia Simples/metabolismo , Estereoisomerismo , Temperatura
14.
ACS Chem Biol ; 8(7): 1402-6, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23614580

RESUMO

We evaluated the abilities of an antisense oligonucleotide (ASO), a small interfering RNA (siRNA), and a single-stranded siRNA (ss-siRNA) to inhibit expression from the PTEN gene in mice when formulated identically with lipid nanoparticles (LNPs). Significantly greater reductions in levels of PTEN mRNA were observed for LNP-formulated agents compared to unformulated drugs when gene silencing was evaluated after a single dose in the livers of mice. An unformulated ss-siRNA modified with a metabolically stable phosphate mimic 5'-(E)-vinylphosphonate showed dose-dependent reduction of PTEN mRNA in mice, albeit at doses significantly higher than those observed for formulated ss-siRNA. These results demonstrate that LNPs can be used to deliver functional antisense and ss-siRNA therapeutics to the liver, indicating that progress in the field of siRNA delivery is transferable to other classes of nucleic acid-based drugs.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Lipídeos/química , Nanopartículas/química , Oligonucleotídeos Antissenso , PTEN Fosfo-Hidrolase/genética , RNA Interferente Pequeno , Animais , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Concentração Inibidora 50 , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/farmacologia , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologia
15.
Cell ; 150(5): 883-94, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22939618

RESUMO

The therapeutic utility of siRNAs is limited by the requirement for complex formulations to deliver them to tissues. If potent single-stranded RNAs could be identified, they would provide a simpler path to pharmacological agents. Here, we describe single-stranded siRNAs (ss-siRNAs) that silence gene expression in animals absent lipid formulation. Effective ss-siRNAs were identified by iterative design by determining structure-activity relationships correlating chemically modified single strands and Argonaute 2 (AGO2) activities, potency in cells, nuclease stability, and pharmacokinetics. We find that the passenger strand is not necessary for potent gene silencing. The guide-strand activity requires AGO2, demonstrating action through the RNAi pathway. ss-siRNA action requires a 5' phosphate to achieve activity in vivo, and we developed a metabolically stable 5'-(E)-vinylphosphonate (5'-VP) with conformation and sterioelectronic properties similar to the natural phosphate. Identification of potent ss-siRNAs offers an additional option for RNAi therapeutics and an alternate perspective on RNAi mechanism.


Assuntos
Proteínas Argonautas/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Células HeLa , Hepatócitos/metabolismo , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Organofosfonatos/metabolismo , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Complexo de Inativação Induzido por RNA/metabolismo , Compostos de Vinila/metabolismo
16.
BMC Public Health ; 12: 389, 2012 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-22642755

RESUMO

BACKGROUND: Fear of weight gain is a barrier to smoking cessation and significant cause of relapse for many people. The provision of nutritional advice as part of a smoking cessation programme may assist some in smoking cessation and perhaps limit weight gain. The aim of this study was to determine the effect of a structured programme of dietary advice on weight change and food choice, in adults attempting smoking cessation. METHODS: Cluster randomised controlled design. Classes randomised to intervention commenced a 24-week intervention, focussed on improving food choice and minimising weight gain. Classes randomised to control received "usual care". RESULTS: Twenty-seven classes in Greater Glasgow were randomised between January and August 2008. Analysis, including those who continued to smoke, showed that actual weight gain and percentage weight gain was similar in both groups. Examination of data for those successful at giving up smoking showed greater mean weight gain in intervention subjects (3.9 (SD 3.1) vs. 2.7 (SD 3.7) kg). Between group differences were not significant (p = 0.23, 95% CI -0.9 to 3.5). In comparison to baseline improved consumption of fruit and vegetables and breakfast cereal were reported in the intervention group. A higher percentage of control participants continued smoking (74% vs. 66%). CONCLUSIONS: The intervention was not successful at minimising weight gain in comparison to control but was successful in facilitating some sustained improvements in the dietary habits of intervention participants. Improved quit rates in the intervention group suggest that continued contact with advisors may have reduced anxieties regarding weight gain and encouraged cessation despite weight gain. Research should continue in this area as evidence suggests that the negative effects of obesity could outweigh the health benefits achieved through reductions in smoking prevalence.


Assuntos
Comportamento de Escolha , Aconselhamento , Dieta/psicologia , Abandono do Hábito de Fumar/métodos , Aumento de Peso , Adulto , Análise por Conglomerados , Dieta/estatística & dados numéricos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Abandono do Hábito de Fumar/psicologia
17.
Int J Epidemiol ; 40(6): 1530-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22158663

RESUMO

BACKGROUND: High serum alanine aminotransferase (ALT) levels have been associated with increased risk of diabetes and with increased mortality, but associations of variations of ALT in the normal range with outcomes have been less well studied. METHODS: We studied the relationship between ALT, mortality and cardiovascular events in the West of Scotland Coronary Prevention Study (WOSCOPS) and the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) trials that explicitly excluded subjects with clinically significant liver damage, plus the Leiden 85-plus, a study of survivors to age 85 years. The associations between ALT and morbidity and mortality outcomes were investigated using Cox proportional hazard models adjusting for a comprehensive panel of cardiovascular risk factors. RESULTS: In all three study cohorts, ALT displayed an independent inverse relationship with all-cause mortality so that hazard ratios for fourth versus first quarter of ALT were all below 1.0; HRs 0.64 [95% confidence interval (CI) 0.50-0.81], 0.86 (0.73-1.01), 0.66 (0.50-0.87); WOSCOPS, PROSPER, Leiden 85-plus, respectively. In WOSCOPS and PROSPER, ALT was also inversely associated with risk of fatal plus non-fatal cardiovascular events, including coronary heart disease (CHD) events and stroke. CONCLUSIONS: In three independent populations, ALT in the normal range displayed an inverse relationship with total mortality, cardiovascular events and non-cardiovascular events in middle-to-older aged subjects without evidence of clinically significant liver damage, independent of traditional cardiovascular and other risk factors. These findings indicate that the relationship between ALT and clinical outcomes is more complex than generally appreciated.


Assuntos
Alanina Transaminase/sangue , Doenças Cardiovasculares/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticolesterolemiantes/uso terapêutico , Pressão Sanguínea , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/tratamento farmacológico , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Fumar/epidemiologia
18.
Arterioscler Thromb Vasc Biol ; 31(10): 2338-44, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21757655

RESUMO

OBJECTIVE: The goal of this study was to examine the association of the antiinflammatory interleukin-10 (IL-10) with risk of cardiovascular disease (CVD). METHODS AND RESULTS: In the PROSPER (PROspective Study of Pravastatin in the Elderly at Risk) cohort, we related baseline concentrations of circulating IL-10 to risk of CVD events in a nested case (n=819)-control (n=1618) study of 3.2 years of follow-up. Circulating IL-10 showed few strong associations with classical risk factors but was positively correlated with IL-6 and C-reactive protein. IL-10 was positively associated with risk of CVD events (odds ratio [OR] 1.17, 95% CI 1.05 to 1.31 per unit increase in log IL-10) after adjusting for classical risk factors and C-reactive protein. Furthermore, IL-10 was associated more strongly with CVD risk among those with no previous history of CVD (OR 1.42, 95% CI 1.18 to 1.70), compared with those with previous CVD (OR 1.04, 95% CI 0.90 to 1.19; P=0.018). Overall, IL-10 showed a modest ability to add discrimination to classical risk factors (C-statistic +0.005, P=0.002). CONCLUSIONS: Baseline circulating levels of the antiinflammatory IL-10 are positively associated with risk of CVD among the elderly without prior CVD events, although the association is less evident in those with a history of CVD. Additional epidemiological and mechanistic studies investigating the role of IL-10 in CVD are warranted.


Assuntos
Envelhecimento , Doenças Cardiovasculares/imunologia , Interleucina-10/sangue , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Estudos de Casos e Controles , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Modelos Logísticos , Masculino , Razão de Chances , Pravastatina/uso terapêutico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
19.
Heart ; 97(7): 564-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21324888

RESUMO

BACKGROUND: The effect of body mass index (BMI) on coronary heart disease (CHD) risk is attenuated when mediators of this risk (such as diabetes, hypertension and hyperlipidaemia) are accounted for. However, there is now evidence of a differential effect of risk factors on fatal and non-fatal CHD events, with markers of inflammation more strongly associated with fatal than non-fatal events. OBJECTIVE: To describe the association with BMI separately for both fatal and non-fatal CHD risk after accounting for classical risk factors and to assess any independent effects of obesity on CHD risk. METHODS AND RESULTS: In the West of Scotland Coronary Prevention Study BMI in 6082 men (mean age 55 years) with hypercholesterolaemia, but no history of diabetes or CVD, was related to the risk of fatal and non-fatal CHD events. After excluding participants with any event in the first 2 years, 1027 non-fatal and 214 fatal CHD events occurred during 14.7 years of follow-up. A minimally adjusted model (age, sex, statin treatment) and a maximally adjusted model (including known CVD risk factors and deprivation) were compared, with BMI 25-27.4 kg/m² as referent. The risk of non-fatal events was similar across all BMI categories in both models. The risk of fatal CHD events was increased in men with BMI 30.0-39.9 kg/m² in both the minimally adjusted model (HR = 1.75 (95% CI 1.12 to 2.74)) and the maximally adjusted model (HR = 1.60 (95% CI 1.02 to 2.53)). CONCLUSIONS: These hypothesis generating data suggest that obesity is associated with fatal, but not non-fatal, CHD after accounting for known cardiovascular risk factors and deprivation. Clinical trial registration WOSCOPS was carried out and completed before the requirement for clinical trial registration.


Assuntos
Doença das Coronárias/etiologia , Obesidade/complicações , Pobreza , Índice de Massa Corporal , Doença das Coronárias/mortalidade , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/complicações , Hipercolesterolemia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Obesidade/mortalidade , Pravastatina/uso terapêutico , Fatores de Risco , Escócia/epidemiologia
20.
Eur Heart J ; 31(10): 1230-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20395260

RESUMO

AIMS: The evidence base for fasting plasma glucose (FPG) in the non-diabetic range as a risk factor for cardiovascular disease (CVD) is inconclusive. We investigated this question in the West of Scotland Coronary Prevention Study (WOSCOPS). METHODS AND RESULTS: In WOSCOPS, we related FPG in 6447 men (mean age 55 years) with hypercholesterolaemia, but no history of CVD or diabetes, to the risk of cardiovascular events and mortality over 14.7 years of follow-up; 2381 non-fatal/fatal cardiovascular events and 1244 deaths occurred. Participants were divided into fifths of baseline FPG, Q1 (< or =4.3 mmol/L) to Q5 (>5.1-6.9 mmol/L). Q2 was designated the referent based on previous studies which have suggested a J-shaped relationship between FPG and CVD. Compared with Q2 (>4.3-4.6 mmol/L), men in Q5 had no elevated risk for cardiovascular events [hazard ratio (HR) 0.95 (0.83-1.08)], or all-cause mortality [HR 0.96 (0.80-1.15)] in fully adjusted analyses despite a significant risk for incident diabetes [HR 22.05 (10.75-45.22)]. After further dividing Q5 into fifths, Q5a-e, individuals in Q5e (FPG 5.8-6.9 mmol/L) were also not at increased risk of cardiovascular events [HR 1.05 (0.82-1.35)] or other endpoints compared with Q2. All results were similar using Q1 as the referent. CONCLUSION: Elevations in FPG in the non-diabetic range were not associated with long-term risk of cardiovascular events in middle-aged men in WOSCOPS. These data suggest that the current FPG cutoff for diagnosing diabetes also appropriately identifies western men at risk of CVD.


Assuntos
Glicemia/metabolismo , Angiopatias Diabéticas/mortalidade , Jejum/sangue , Doença das Coronárias/mortalidade , Angiopatias Diabéticas/sangue , Feminino , Seguimentos , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Escócia/epidemiologia
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