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1.
Front Med (Lausanne) ; 9: 1064003, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569125

RESUMO

In medicines development, the progress in science and technology is accelerating. Awareness of these developments and their associated challenges and opportunities is essential for medicines regulators and others to translate them into benefits for society. In this context, the European Medicines Agency uses horizon scanning to shine a light on early signals of relevant innovation and technological trends with impact on medicinal products. This article provides the results of systematic horizon scanning exercises conducted by the Agency, in collaboration with the World Health Organization (WHO) and the European Commission's Joint Research Centre's (DG JRC). These collaborative exercises aim to inform policy-makers of new trends and increase preparedness in responding to them. A subset of 25 technological trends, divided into three clusters were selected and reviewed from the perspective of medicines regulators. For each of these trends, the expected impact and challenges for their adoption are discussed, along with recommendations for developers, regulators and policy makers.

2.
Anal Chem ; 91(16): 10458-10466, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31373797

RESUMO

High-throughput screening platforms for the identification of bioactive compounds in mixtures have become important tools in the drug discovery process. Miniaturization of such screening systems may overcome problems associated with small sample volumes and enhance throughput and sensitivity. Here we present a new screening platform, coined picofractionation analytics, which encompasses microarray bioassays and mass spectrometry (MS) of components from minute amounts of samples after their nano liquid chromatographic (nanoLC) separation. Herein, nanoLC was coupled to a low-volume liquid dispenser equipped with pressure-fed solenoid valves, enabling 50-nL volumes of column effluent (300 nL/min) to be discretely deposited on a glass slide. The resulting fractions were dried and subsequently bioassayed by sequential printing of nL-volumes of reagents on top of the spots. Unwanted evaporation of bioassay liquids was circumvented by employing mineral oil droplets. A fluorescence microscope was used for assay readout in kinetic mode. Bioassay data were correlated to MS data obtained using the same nanoLC conditions in order to assign bioactives. The platform provides the possibility of freely choosing a wide diversity of bioassay formats, including those requiring long incubation times. The new method was compared to a standard bioassay approach, and its applicability was demonstrated by screening plasmin inhibitors and fibrinolytic bioactives from mixtures of standards and snake venoms, revealing active peptides and coagulopathic proteases.


Assuntos
Antifibrinolíticos/isolamento & purificação , Bioensaio , Cromatografia Líquida/métodos , Fibrinolíticos/isolamento & purificação , Nanotecnologia/métodos , Peptídeo Hidrolases/isolamento & purificação , Animais , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Cromatografia Líquida/instrumentação , Humanos , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Nanotecnologia/instrumentação , Peptídeo Hidrolases/análise , Venenos de Serpentes/química , Serpentes/metabolismo
3.
Anal Bioanal Chem ; 410(23): 5751-5763, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30090989

RESUMO

To better understand envenoming and to facilitate the development of new therapies for snakebite victims, rapid, sensitive, and robust methods for assessing the toxicity of individual venom proteins are required. Metalloproteinases comprise a major protein family responsible for many aspects of venom-induced haemotoxicity including coagulopathy, one of the most devastating effects of snake envenomation, and is characterized by fibrinogen depletion. Snake venoms are also known to contain anti-fibrinolytic agents with therapeutic potential, which makes them a good source of new plasmin inhibitors. The protease plasmin degrades fibrin clots, and changes in its activity can lead to life-threatening levels of fibrinolysis. Here, we present a methodology for the screening of plasmin inhibitors in snake venoms and the simultaneous assessment of general venom protease activity. Venom is first chromatographically separated followed by column effluent collection onto a 384-well plate using nanofractionation. Via a post-column split, mass spectrometry (MS) analysis of the effluent is performed in parallel. The nanofractionated venoms are exposed to a plasmin bioassay, and the resulting bioassay activity chromatograms are correlated to the MS data. To study observed proteolytic activity of venoms in more detail, venom fractions were exposed to variants of the plasmin bioassay in which the assay mixture was enriched with zinc or calcium ions, or the chelating agents EDTA or 1,10-phenanthroline were added. The plasmin activity screening system was applied to snake venoms and successfully detected compounds exhibiting antiplasmin (anti-fibrinolytic) activities in the venom of Daboia russelii, and metal-dependent proteases in the venom of Crotalus basiliscus. Graphical abstract ᅟ.


Assuntos
Antifibrinolíticos/análise , Fibrinolisina/antagonistas & inibidores , Espectrometria de Massas/instrumentação , Peptídeo Hidrolases/análise , Proteínas de Répteis/análise , Venenos de Víboras/química , Venenos de Víboras/enzimologia , Viperidae , Animais , Antifibrinolíticos/farmacologia , Fracionamento Químico/instrumentação , Cromatografia Líquida/instrumentação , Avaliação Pré-Clínica de Medicamentos/instrumentação , Desenho de Equipamento , Fibrinolisina/metabolismo , Humanos , Nanotecnologia/instrumentação , Peptídeo Hidrolases/farmacologia , Proteômica/métodos , Proteínas de Répteis/farmacologia , Viperidae/metabolismo
4.
SLAS Discov ; 23(3): 283-293, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29262760

RESUMO

With early assessment of inhibitory properties of drug candidates and their circulating metabolites toward cytochrome P450 enzymes, drug attrition, especially later in the drug development process, can be decreased. Here we describe the development and validation of an at-line nanofractionation platform, which was applied for screening of CYP1A2 inhibitors in Phase I metabolic mixtures. With this platform, a metabolic mixture is separated by liquid chromatography (LC), followed by parallel nanofractionation on a microtiter well plate and mass spectrometry (MS) analysis. After solvent evaporation, all metabolites present in the nanofractionated mixture are assayed utilizing a fluorescence CYP1A2 inhibition bioassay performed on the plate. Next, a bioactivity chromatogram is constructed from the bioassay results. By peak shape and retention time correlation of the bioactivity peaks with the obtained MS data, CYP1A2-bioactive inhibiting metabolites can be identified. The method correctly evaluated the potency of five CYP1A2 inhibitors. Mixtures comprising potent inhibitors of CYP1A2 or in vitro-generated metabolites of ellipticine were evaluated for their inhibitory bioactivities. In both cases, good LC separation of all compounds was achieved and bioactivity data could be accurately correlated with the parallel recorded MS data. Generation and evaluation of Phase II metabolites of hydroxylated ellipticine was also pursued.


Assuntos
Inibidores do Citocromo P-450 CYP1A2/farmacologia , Citocromo P-450 CYP1A2/metabolismo , Inibidores Enzimáticos/farmacologia , Bioensaio/métodos , Cromatografia Líquida/métodos , Humanos , Espectrometria de Massas/métodos , Desintoxicação Metabólica Fase I/fisiologia , Desintoxicação Metabólica Fase II/fisiologia
5.
Toxicon ; 110: 79-89, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26708656

RESUMO

Snake venoms comprise complex mixtures of peptides and proteins causing modulation of diverse physiological functions upon envenomation of the prey organism. The components of snake venoms are studied as research tools and as potential drug candidates. However, the bioactivity determination with subsequent identification and purification of the bioactive compounds is a demanding and often laborious effort involving different analytical and pharmacological techniques. This study describes the development and optimization of an integrated analytical approach for activity profiling and identification of venom constituents targeting the cardiovascular system, thrombin and factor Xa enzymes in particular. The approach developed encompasses reversed-phase liquid chromatography (RPLC) analysis of a crude snake venom with parallel mass spectrometry (MS) and bioactivity analysis. The analytical and pharmacological part in this approach are linked using at-line nanofractionation. This implies that the bioactivity is assessed after high-resolution nanofractionation (6 s/well) onto high-density 384-well microtiter plates and subsequent freeze drying of the plates. The nanofractionation and bioassay conditions were optimized for maintaining LC resolution and achieving good bioassay sensitivity. The developed integrated analytical approach was successfully applied for the fast screening of snake venoms for compounds affecting thrombin and factor Xa activity. Parallel accurate MS measurements provided correlation of observed bioactivity to peptide/protein masses. This resulted in identification of a few interesting peptides with activity towards the drug target factor Xa from a screening campaign involving venoms of 39 snake species. Besides this, many positive protease activity peaks were observed in most venoms analysed. These protease fingerprint chromatograms were found to be similar for evolutionary closely related species and as such might serve as generic snake protease bioactivity fingerprints in biological studies on venoms.


Assuntos
Antitrombinas/isolamento & purificação , Descoberta de Drogas/métodos , Inibidores do Fator Xa/isolamento & purificação , Proteínas de Répteis/isolamento & purificação , Venenos de Serpentes/química , Animais , Antitrombinas/metabolismo , Antitrombinas/farmacologia , Bovinos , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Fator Xa/química , Fator Xa/metabolismo , Inibidores do Fator Xa/metabolismo , Inibidores do Fator Xa/farmacologia , Corantes Fluorescentes/química , Humanos , Cinética , Nanotecnologia , Filogenia , Proteínas de Répteis/genética , Proteínas de Répteis/metabolismo , Proteínas de Répteis/farmacologia , Rodaminas/química , Espectrometria de Fluorescência , Espectrometria de Massas por Ionização por Electrospray , Trombina/antagonistas & inibidores , Trombina/metabolismo
6.
Gastroenterology ; 148(2): 367-78, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25447851

RESUMO

BACKGROUND & AIMS: Barrett's esophagus (BE) increases the risk of esophageal adenocarcinoma (EAC). We found the risk to be BE has been associated with single nucleotide polymorphisms (SNPs) on chromosome 6p21 (within the HLA region) and on 16q23, where the closest protein-coding gene is FOXF1. Subsequently, the Barrett's and Esophageal Adenocarcinoma Consortium (BEACON) identified risk loci for BE and esophageal adenocarcinoma near CRTC1 and BARX1, and within 100 kb of FOXP1. We aimed to identify further SNPs that increased BE risk and to validate previously reported associations. METHODS: We performed a genome-wide association study (GWAS) to identify variants associated with BE and further analyzed promising variants identified by BEACON by genotyping 10,158 patients with BE and 21,062 controls. RESULTS: We identified 2 SNPs not previously associated with BE: rs3072 (2p24.1; odds ratio [OR] = 1.14; 95% CI: 1.09-1.18; P = 1.8 × 10(-11)) and rs2701108 (12q24.21; OR = 0.90; 95% CI: 0.86-0.93; P = 7.5 × 10(-9)). The closest protein-coding genes were respectively GDF7 (rs3072), which encodes a ligand in the bone morphogenetic protein pathway, and TBX5 (rs2701108), which encodes a transcription factor that regulates esophageal and cardiac development. Our data also supported in BE cases 3 risk SNPs identified by BEACON (rs2687201, rs11789015, and rs10423674). Meta-analysis of all data identified another SNP associated with BE and esophageal adenocarcinoma: rs3784262, within ALDH1A2 (OR = 0.90; 95% CI: 0.87-0.93; P = 3.72 × 10(-9)). CONCLUSIONS: We identified 2 loci associated with risk of BE and provided data to support a further locus. The genes we found to be associated with risk for BE encode transcription factors involved in thoracic, diaphragmatic, and esophageal development or proteins involved in the inflammatory response.


Assuntos
Esôfago de Barrett/genética , Proteínas Morfogenéticas Ósseas/genética , Predisposição Genética para Doença , Fatores de Diferenciação de Crescimento/genética , Polimorfismo de Nucleotídeo Único , Proteínas com Domínio T/genética , Esôfago de Barrett/etiologia , Neoplasias Esofágicas/genética , Estudo de Associação Genômica Ampla , Humanos , Risco
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