RESUMO
Lipids contained in the plasma membrane of platelets play an important role in platelet function. Modifications in the lipid composition can fluidify or rigidify the environment around embedded receptors, in order to facilitate the access of the receptor by the drug. However, data concerning the lipid composition of platelet plasma membrane need to be updated. In addition, data on the impact of drugs on plasma membrane composition, in particular antiplatelet agents, remain sparse. After isolation of platelet plasma membrane, we assessed, using lipidomics, the effect of ticagrelor, a P2Y12 antagonist, and its active metabolite on the lipid composition of these plasma membranes. We describe the exact lipid composition of plasma membrane, including all sub-species. Ticagrelor and its active metabolite significantly increased cholesterol and phosphatidylcholine ether with short saturated acyl chains 16:0/16:0, and decreased phosphatidylcholine, suggesting overall rigidification of the membrane. Furthermore, ticagrelor and its active metabolite decreased some arachidonylated plasmalogens, suggesting a decrease in availability of arachidonic acid from the membrane phospholipids for synthesis of biologically active mediators. To conclude, ticagrelor and its active metabolite seem to influence the lipid environment of receptors embedded in the lipid bilayer and modify the behavior of the plasma membrane.
Assuntos
Lipidômica , Lipídeos/análise , Inibidores da Agregação Plaquetária/farmacologia , Ticagrelor/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Membrana Celular/metabolismo , Humanos , Testes de Função PlaquetáriaRESUMO
Ticagrelor is an antiplatelet agent which is extensively metabolized in an active metabolite: AR-C124910XX. Ticagrelor antagonizes P2Y12 receptors, but recently, this effect on the central nervous system has been linked to the development of dyspnea. Ticagrelor-related dyspnea has been linked to persistently high plasma concentrations of ticagrelor. Therefore, there is a need to develop a simple, rapid, and sensitive method for simultaneous determination of ticagrelor and its active metabolite in human plasma to further investigate the link between concentrations of ticagrelor, its active metabolite, and side effects in routine practice. We present here a new method of quantifying both molecules, suitable for routine practice, validated according to the latest Food and Drug Administration (FDA) guidelines, with a good accuracy and precision (<15% respectively), except for the lower limit of quantification (<20%). We further describe its successful application to plasma samples for a population pharmacokinetics study. The simplicity and rapidity, the wide range of the calibration curve (2-5000 µg/L for ticagrelor and its metabolite), and high throughput make a broad spectrum of applications possible for our method, which can easily be implemented for research, or in daily routine practice such as therapeutic drug monitoring to prevent overdosage and occurrence of adverse events in patients.
Assuntos
Espectrometria de Massas em Tandem , Ticagrelor/química , Ticagrelor/farmacocinética , Cromatografia Líquida de Alta Pressão , HumanosRESUMO
Platelet protease-activated receptor 1 (PAR1) is a cell surface G-protein-coupled receptor (GPCR) that acts as a thrombin receptor promoting platelet aggregation. Targeting the PAR1 pathway by vorapaxar, a PAR1 antagonist, leads to a reduction in ischemic events in cardiovascular patients with a history of myocardial infarction or with peripheral arterial disease. In platelets, specialized microdomains highly enriched in cholesterol act as modulators of the activity of several GPCRs and play a pivotal role in the signaling pathway. However, their involvement in platelet PAR1 function remains incompletely characterized. In this context, we aimed to investigate whether activation of PAR1 in human platelets requires its localization in the membrane cholesterol-rich microdomains. Using confocal microscopy, biochemical isolation, and proteomics approaches, we found that PAR1 was not localized in cholesterol-rich microdomains in resting platelets, and only a small fraction of the receptor relocated to the microdomains following its activation. Vorapaxar treatment increased the level of PAR1 at the platelet surface, possibly by reducing its endocytosis, while its colocalization with cholesterol-rich microdomains remained weak. Consistent with a cholesterol-dependent activation of Akt and p38 MAP kinase in thrombin receptor-activating peptide (TRAP)-activated platelets, the proteomic data of cholesterol-rich microdomains isolated from TRAP-activated platelets showed the recruitment of proteins contributing to these signaling pathways. In conclusion, contrary to endothelial cells, we found that PAR1 was only weakly present in cholesterol-rich microdomains in human platelets but used these microdomains for efficient activation of downstream signaling pathways following TRAP activation.
Assuntos
Plaquetas/metabolismo , Colesterol/metabolismo , Microdomínios da Membrana/metabolismo , Agregação Plaquetária , Proteoma/análise , Receptor PAR-1/metabolismo , Humanos , Inibidor 1 de Ativador de Plasminogênio , Transdução de SinaisRESUMO
Farming insects has recently emerged as a new source of protein and lipid production. To date, research has mostly focused on food applications of insects. Focusing on nonfood potential of oil and proteins of insects, high-throughput studies of insect lipids and proteins are needed. We performed proteomics and lipidomics investigation on black soldier fly (Hermitia illucens) and blow fly (Lucilia sericata) larvae to investigate new potential and applications. We used mass spectrometry for proteomics and lipidomics analysis of control and treated larvae. Treatment was performed by incubation with a biological decomposer. We provide the list of all fatty acids with their concentration in control and treated larvae. This result showed high levels of lauric acid in black soldier fly, which could even increase after biological decomposition. Proteomics analysis showed the presence of proteins like collagen of cosmetic interest, and proteins with antimicrobial properties such as phenoloxidases and enzymatic activities, such as amylase and trypsin. Insects harbor high potential for nonfood usage as additives, antimicrobial effects, and even pharmaceuticals and cosmetics. These data open avenues for future research in pharmacological and cosmetic approaches to find new molecules of interests.
Assuntos
Dípteros/metabolismo , Metabolismo dos Lipídeos , Proteoma , Animais , Anti-Infecciosos/análise , Dípteros/química , Dípteros/genética , Proteínas de Insetos/análise , Larva/química , Larva/metabolismo , Lipídeos/análise , ProteômicaRESUMO
Cardiovascular diseases are among the leading causes of morbidity and mortality. Despite scientific and technical progress in risk prediction, diagnostics, prognostication and therapy of cardiovascular pathologies, new biomarkers and therapeutic targets remain the subject of intense research to reduce the burden of these diseases. High throughput analyses, termed "omics", are a promising avenue of research. These recently developed technical fields have revolutionized biological and medical research in a very short time. By their interdisciplinary nature, these new methods have already provided a wide vision of cell and tissue pathways and functions. Here, we review how these methods can help to discover new biomarkers and therapeutic targets in cardiovascular diseases.
Assuntos
Biomarcadores , Doenças Cardiovasculares/genética , Genômica/métodos , Proteômica/métodos , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/terapia , Humanos , Terapia de Alvo MolecularRESUMO
Ticagrelor is an antiplatelet agent that inhibits platelet activation via P2Y12 antagonism. There are several studies showing that P2Y12 needs lipid rafts to be activated, but there are few data about how ticagrelor impacts lipid raft organization. Therefore, we aimed to investigate how ticagrelor could impact the distribution of cholesterol and consequently alter the organization of lipid rafts on platelet plasma membranes. We identified cholesterol-enriched raft fractions in platelet membranes by quantification of their cholesterol levels. Modifications in cholesterol and protein profiles (Flotillin 1, Flotillin 2, CD36, P2Y1, and P2Y12) were studied in platelets stimulated by ADP, treated by ticagrelor, or both. In ADP-stimulated and ticagrelor-treated groups, we found a decreased level of cholesterol in raft fractions of platelet plasma membrane compared to the control group. In addition, the peak of cholesterol in different experimental groups changed its localization on membrane fractions. In the control group, it was situated on fraction 2, while in ADP-stimulated platelets, it was located in fractions 3 to 5, and in fraction 4 in ticagrelor-treated group. The proteins studied also showed changes in their level of expression and localization in fractions of plasma membrane. Cholesterol levels of plasma membranes have a direct role in the organization of platelet membranes and could be modified by stimulation or drug treatment. Since ticagrelor and ADP both changed lipid composition and protein profile, investigating the lipid and protein composition of platelet membranes is of considerable importance as a focus for further research in anti-platelet management.
Assuntos
Adenosina/análogos & derivados , Plaquetas/metabolismo , Membrana Celular/metabolismo , Colesterol/sangue , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Receptores Purinérgicos P2Y12/metabolismo , Receptores Purinérgicos P2Y1/metabolismo , Adenosina/farmacologia , Humanos , Microdomínios da Membrana/metabolismo , TicagrelorRESUMO
Lipid-rafts are defined as membrane microdomains enriched in cholesterol and glycosphingolipids within platelet plasma membrane. Lipid raft-mediated clot retraction requires factor XIII and other interacting proteins. The aim of this study was to investigate the proteins that interact with factor XIII in raft and non-raft domains of activated and non-activated platelet plasma membrane. By lipidomics analysis, we identified cholesterol- and sphingomyelin-enriched areas as lipid rafts. Platelets were activated by thrombin. Proteomics analysis provided an overview of the pathways in which proteins of rafts and non-rafts participated in the interaction network of FXIII-A1, a catalytic subunit of FXIII. "Platelet activation" was the principal pathway among KEGG pathways for proteins of rafts, both before and after activation. Network analysis showed four types of interactions (activation, binding, reaction, and catalysis) in raft and non-raft domains in interactive network of FXIII-A1. FXIII-A1 interactions with other proteins in raft domains and their role in homeostasis highlight the specialization of the raft domain in clot retraction via the Factor XIII protein network.
Assuntos
Plaquetas/metabolismo , Fator XIII/metabolismo , Microdomínios da Membrana/metabolismo , Ativação Plaquetária , Subunidades Proteicas/metabolismo , Retração do Coágulo , Fator XIII/química , Humanos , Ligação Proteica , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Proteoma , Proteômica/métodos , Transdução de SinaisRESUMO
Lipid rafts play a pivotal role in physiological functions of platelets. Their isolation using nonionic mild detergents is considered as the gold standard method, but there is no consensual detergent for lipid raft studies. We aimed to investigate which detergent is the most suitable for lipid raft isolation from platelet membrane, based on lipidomics and proteomics analysis. Platelets were obtained from healthy donors. Twelve sucrose fractions were extracted by three different detergents, namely Brij 35, Lubrol WX, and Triton X100, at 0.05% and 1%. After lipidomics analysis and determination of fractions enriched in cholesterol (Ch) and sphingomyelin (SM), proteomics analysis was performed. Lipid rafts were mainly observed in 1-4 fractions, and non-rafts were distributed on 5-12 fractions. Considering the concentration of Ch and SM, Lubrol WX 1% and Triton X100 1% were more suitable detergents as they were able to isolate lipid raft fractions that were more enriched than non-raft fractions. By proteomics analysis, overall, 822 proteins were identified in platelet membrane. Lipid raft fractions isolated with Lubrol WX 0.05% and Triton X100 1% contained mainly plasma membrane proteins. However, only Lubrol WX 0.05 and 1% and Triton X100 1% were able to extract non-denaturing proteins with more than 10 transmembrane domains. Our results suggest that Triton X100 1% is the most suitable detergent for global lipid and protein studies on platelet plasma membrane. However, the detergent should be adapted if investigation of an association between specific proteins and lipid rafts is planned.
Assuntos
Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Detergentes/farmacologia , Lipídeos , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Proteoma , Proteômica , Centrifugação com Gradiente de Concentração , Humanos , Proteínas de Membrana , Proteômica/métodosRESUMO
BACKGROUND: We evaluated prognostic value at 6 months of residual pulmonary vascular obstruction (RPVO) measured before discharge in patients with intermediate- or high-risk pulmonary embolism (PE). METHODS AND RESULTS: Prospective registry including 416 consecutive patients with intermediate- or high-risk PE who survived the acute phase. Patients with previous cardiopulmonary disease were excluded. Perfusion lung scans were performed within 6-8 days after the onset of treatment. Residual pulmonary vascular obstruction was graded as the proportion of the lung not perfused. Primary objective was a combined endpoint at 6 months, including death, recurrent PE, and appearance of signs of heart failure. At 6 months, 32 patients (7.7%) had at least one adverse event: 12 deaths (2.9%), 12 recurrent PE (2.9%), and 14 (3.4%) heart failure. Independent predictors of combined endpoint were: cancer [odds ratio (OR) 3.07 (1.22-7.85)]; renal insufficiency at admission [OR: 2.53 (1.17-5.8)]; persistent signs of right ventricular dysfunction at 48 h echography [OR: 3.99 (1.36-11.3)]. The severity of RPVO at discharge was significantly associated with an unfavourable outcome [OR: 2.66 (1.58-3.93)]. The incremental prognostic value of RPVO information was confirmed by significantly improved goodness-of-fit. Threshold RPVO for predicting adverse events was estimated at 35% [area under the curve = 0.76 (0.73-0.82)]. Patients with RPVO greater than threshold at discharge had a significantly higher risk of death at 6 months (P = 0.01). CONCLUSIONS: Residual pulmonary vascular obstruction evaluated before hospital discharge in patients with intermediate- to high-risk PE is a powerful prognostic factor for a 6-month outcome. RPVO ≥35% is associated with an increased risk of adverse events at 6 months.
Assuntos
Arteriopatias Oclusivas/mortalidade , Artéria Pulmonar , Embolia Pulmonar/mortalidade , Idoso , Anticoagulantes/uso terapêutico , Feminino , Insuficiência Cardíaca/mortalidade , Hemorragia/etiologia , Heparina/uso terapêutico , Humanos , Masculino , Tomografia Computadorizada Multidetectores , Neoplasias/mortalidade , Prognóstico , Estudos Prospectivos , Embolia Pulmonar/prevenção & controle , Recidiva , Insuficiência Renal/mortalidade , Medição de Risco , Fatores de Risco , Terapia Trombolítica/métodos , Tromboembolia Venosa/mortalidade , Disfunção Ventricular Direita/mortalidadeRESUMO
BACKGROUND AND PURPOSE: Although the amphiphilic nature of the widely used antithrombotic drug Ticagrelor is well known, it was never considered as a membranotropic agent capable of interacting with the lipid bilayer in a receptor-independent way. In this study, we investigated the influence of Ticagrelor on plasma membrane lipid order in platelets and if this modulates the potency of Ticagrelor at the P2Y12 receptor. EXPERIMENTAL APPROACH: We combined fluorescent in situ, in vitro and in silico approaches to probe the interactions between the plasma membrane of platelets and Ticagrelor. The influence of Ticagrelor on the lipid order of the platelet plasma membrane and large unilamellar vesicles was studied using the advanced fluorescent probe NR12S. Furthermore, the properties of model lipid bilayers in the presence of Ticagrelor were characterized by molecular dynamics simulations. Finally, the influence of an increased lipid order on the dose-response of platelets to Ticagrelor was studied. KEY RESULTS: Ticagrelor incorporates spontaneously into lipid bilayers and affects the lipid order of the membranes of model vesicles and isolated platelets, in a nontrivial composition and concentration-dependent manner. We showed that higher plasma membrane lipid order in platelets leads to a lower IC50 value for Ticagrelor. It is shown that membrane incorporation of Ticagrelor increases its potency at the P2Y12 receptor, by increasing the order of the platelet plasma membrane. CONCLUSION AND IMPLICATIONS: A novel dual mechanism of Ticagrelor action is suggested that combines direct binding to P2Y12 receptor with simultaneous modulation of receptor-lipid microenvironment.
RESUMO
Large numbers of monocytes are recruited in the infarcted myocardium. Their cell membranes contain cholesterol-rich microdomains called lipids rafts, which participate in numerous signaling cascades. In addition to its cholesterol-lowering effect, pravastatin has several pleiotropic effects and is widely used as secondary prevention treatment after myocardial infarction (MI). The aim of this study was to investigate the effects of pravastatin on the organization of cholesterol within monocyte membrane rafts from patients who had suffered myocardial infarction. Monocytes from healthy donors and acute MI patients were cultured with or without 4µM pravastatin. Lipid rafts were extracted by Lubrol WX, caveolae and flat rafts were separated using a modified sucrose gradient. Cholesterol level and caveolin-1 expression in lipid rafts were determined. In healthy donors, cholesterol was concentrated in flat rafts (63±3 vs 13±1%, p<0.001). While monocytes from MI patients presented similar cholesterol distribution in both caveolae and flat rafts. Cholesterol distribution was higher in flat rafts in healthy donors, compared to MI patients (63±3 vs 41±2%, p<0.001), with less distribution in caveolae (13±1 vs 34±2%, p<0.001). Pravastatin reversed the cholesterol distribution in MI patients cells between flat rafts (41±2 vs 66±3%, p<0.001) and caveolae (34±2 vs 18±1%, p<0.001). In conclusion, MI redistributes cholesterol from flat rafts to caveolae indicating monocyte membrane reorganization. In vitro pravastatin treatment restored basal conditions in MI monocytes, suggesting another effect of statins.
Assuntos
Anticolesterolemiantes/farmacologia , Cavéolas/metabolismo , Colesterol/metabolismo , Receptores de Lipopolissacarídeos , Monócitos/metabolismo , Infarto do Miocárdio/metabolismo , Pravastatina/farmacologia , Receptores de IgG , Adulto , Cavéolas/patologia , Caveolina 1/biossíntese , Células Cultivadas , Feminino , Proteínas Ligadas por GPI , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/patologia , Infarto do Miocárdio/patologiaRESUMO
OBJECTIVE: To determine the relationship between the number of CD14(+) cells, myocardial infarct (MI) size and left ventricular (LV) volumes in ST segment elevation MI (STEMI) and non-ST segment elevation MI (NSTEMI) patients. METHODS: A total of 62 patients with STEMI (n=34) or NSTEMI (n=28) were enrolled. The number of CD14(+) cells was assessed at admission. Infarct size, left ventricular ejection fraction (LVEF) and LV volumes were measured using magnetic resonance imaging five days after MI and six months after MI. RESULTS: In STEMI patients, the number of CD14(+) cells was positively and significantly correlated with infarct size at day 5 (r=0.40; P=0.016) and after six months (r=0.34; P=0.047), negatively correlated with LVEF at day 5 (r=-0.50; P=0.002) and after six months (r=-0.46; P=0.005) and positively correlated with end-diastolic (r=0.38; P=0.02) and end-systolic (r=0.49; P=0.002) volumes after six months. In NSTEMI patients, no significant correlation was found between the number of CD14(+) cells and infarct size, LVEF or LV volumes at day 5 or after six months. CONCLUSIONS: The number of CD14(+) cells at admission was associated with infarct size and LV remodelling in STEMI patients with large infarct size, whereas in NSTEMI patients, no relationship was observed between numbers of CD14(+) cells and LV remodelling.
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Molecular modeling in pharmacology is a promising emerging tool for exploring drug interactions with cellular components. Recent advances in molecular simulations, big data analysis, and artificial intelligence (AI) have opened new opportunities for rationalizing drug interactions with their pharmacological targets. Despite the obvious utility and increasing impact of computational approaches, their development is not progressing at the same speed in different fields of pharmacology. Here, we review current in silico techniques used in cardiovascular diseases (CVDs), cardiological drug discovery, and assessment of cardiotoxicity. In silico techniques are paving the way to a new era in cardiovascular medicine, but their use somewhat lags behind that in other fields.
Assuntos
Inteligência Artificial , Descoberta de Drogas , Big Data , Descoberta de Drogas/métodos , Modelos MolecularesRESUMO
AIM OF THE STUDY: Serious adverse drug reactions account for 3.6% of French hospital admissions. Of these, 48.5% are, at least potentially, preventable. The first aim of post-marketing pharmacovigilance is to detect adverse drug reactions as a safety signal to improve patients' safety. Thus, this study describes the epidemiology of "serious" adverse drug reactions reported between 2015 and 2018 to a regional pharmacovigilance centre and assesses their economic burden. METHODS: All "serious" adverse drug reactions reported to a regional pharmacovigilance centre during the four-year study period were collected and cost associated. Only congenital anomalies related to "serious" adverse drug reactions were excluded. RESULTS: All 2585 "serious" adverse drug reactions reported are related to 1242 "serious" individual case safety reports. Among 58.1% of them, patients required hospital admission or a visit to the emergency room with a median cost estimated to 3725 per "serious" individual case safety report. The most "serious" adverse drug reactions reported involved gastrointestinal disorders. Fifteen percent of the imputed drugs had a narrow therapeutic index and the most frequently drug was fluindione. Finally, high relationships with an economic burden were observed for ages over or equal to 65, and imputed drugs from "Blood and Blood-Forming Organs" and "Anti-infectives for systemic use" therapeutic groups. CONCLUSION: This study provides news data on epidemiology and cost of "serious" adverse drug reactions completing the existing literature. On a regional scale, pharmacovigilance real world data could be interesting for pharmacist clinicians in common practice to improve the good use of drugs.
Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Farmacovigilância , Sistemas de Notificação de Reações Adversas a Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Estresse Financeiro , Humanos , FarmacêuticosRESUMO
INTRODUCTION: Pre-exposure prophylaxis (PrEP) is a combination of antiretroviral regimen, tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) that has been shown to prevent HIV transmission. It had been regulated through a temporary recommendation use since December 2015 and had marketing authorization in France since March 2017. As, this product is proposed for adults and adolescents safe from HIV but at high risk of infection, the question is to know if there is a safety concern about this use. METHODS: A request has been made in the French national pharmacovigilance database (ANPV) and VIGILYZE for an extraction of all cases containing TDF/FTC as suspect drugs in PrEP use. In the second part, we did a literature review in PubMED with MeSH terms and an analysis of the results of the American, English and French initial clinical trials was performed. RESULTS: In both database, 808 cases correspond to an indication of HIV prexposure prophylaxis who represent 2058 adverse effects (AEs) mainly distributed in gastro-intestinal disorders (38.5%), general disorders (16.8%) and 62 cases of seroconversion. We identify 24% of unexpected AEs including 12% of serious AEs in the French database. In literature review, there are no unexpected AEs published, the AEs are mainly gastro-intestinal disorders. There was no significant difference in the AE profile compared to the HIV-infected population treated with TDF/FTC. CONCLUSION: Data from the ANPV, combined with data from the worldwide pharmacovigilance database, show that the most commonly observed AEs are gastrointestinal, mainly nausea, vomiting and diarrhea. A significant number of asthenia and fatigue are also observed. These AEs are well described in the SMPc. However, we have little data, which can be explained by a probable under-reporting of AEs. We identify 24% of unexpected and potentially serious adverse effects in France mainly among chemsex users. Based on these results, our study confirms the safety of PrEP.
Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Adulto , Adolescente , Humanos , Estados Unidos , Emtricitabina/efeitos adversos , Tenofovir/efeitos adversos , Profilaxia Pré-Exposição/métodos , Fármacos Anti-HIV/efeitos adversos , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológicoRESUMO
We report here a drug-drug interaction with tacrolimus in a HIV-positive patient with renal transplant, after switch from highly active antiretroviral therapy with boosted protease inhibitors to the combination bictegravir/emtricitabine/tenofovir alafenamide. Although the tacrolimus doses were adapted to take account of the pharmacokinetic interactions with protease inhibitors, a tacrolimus overdosage occurred in the patient nonetheless. Through this case report, we highlight the need to consider a sufficient timeframe of withdrawal of protease inhibitors, which induce a prolonged drug-drug interaction with tacrolimus. To conclude, we purport that the combination bictegravir/emtricitabine/tenofovir alafenamide could be an attractive alternative in the context of transplantation provided a discontinuation of boosted protease inhibitors for more than 48 hours before introducing tacrolimus.
Assuntos
Fármacos Anti-HIV , Infecções por HIV , Transplante de Rim , Adenina , Alanina , Amidas , Fármacos Anti-HIV/uso terapêutico , Combinação de Medicamentos , Emtricitabina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Piperazinas , Inibidores de Proteases/uso terapêutico , Piridonas , Tacrolimo/uso terapêutico , Tenofovir/análogos & derivadosRESUMO
Endothelial colony-forming cells (ECFCs) are known to increase after acute myocardial infarction (AMI). We examined whether the presence of ECFCs is associated with preserved microvascular integrity in the myocardium at risk by reducing microvascular obstruction (MVO). We enrolled 88 patients with a first ST elevation AMI. ECFC colonies and circulating progenitor cells were characterized at admission. MVO was evaluated at 5 days and infarct size at 5 days and at 6-month follow-up by magnetic resonance imaging. ECFC colonies were detected in 40 patients (ECFC(pos) patients). At 5 days, MVO was of greater magnitude in ECFC(neg) versus ECFC(pos) patients (7.7 ± 5.3 vs. 3.2 ± 5%, p = 0.0002). At 6 months, in ECFC(pos) patients, there was a greater reduction in infarct size (-32.4 ± 33 vs. -12.8 ± 24%; p = 0.003) and a significant improvement in left ventricular (LV) volumes and ejection fraction. Level of circulating CD34+/VEGF-R2+ cells was correlated with the number of ECFC colonies (r = 0.54, p < 0.001) and relative change in infarct size (r = 0.71, p < 0.0001). The results showed that the presence of ECFC colonies is associated with reduced MVO after AMI, leading to reduced infarct size and less LV remodelling and can be considered a marker of preserved microvascular integrity in AMI patients.
Assuntos
Células Endoteliais/citologia , Infarto do Miocárdio/patologia , Neovascularização Fisiológica/fisiologia , Células-Tronco/citologia , Remodelação Ventricular/fisiologia , Vasos Coronários/citologia , Vasos Coronários/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Microvasos/citologia , Pessoa de Meia-Idade , FenótipoRESUMO
The binding of natural ligands and synthetic drugs to the P2Y12 receptor is of great interest because of its crucial role in platelets activation and the therapy of arterial thrombosis. Up to now, all computational studies of P2Y12 concentrated on the available crystal structures, while the role of intrinsic protein dynamics and the membrane environment in the functioning of P2Y12 was not clear. In this work, we performed all-atom molecular dynamics simulations of the full-length P2Y12 receptor in three different membrane environments and in two possible conformations derived from available crystal structures. The binding of ticagrelor, its two major metabolites, adenosine diphosphate (ADP) and 2-Methylthioadenosine diphosphate (2MeS-ADP) as agonist, and ethyl 6-[4-(benzylsulfonylcarbamoyl)piperidin-1-yl]-5-cyano-2-methylpyridine-3-carboxylate (AZD1283)as antagonist were assessed systematically by means of ensemble docking. It is shown that the binding of all ligands becomes systematically stronger with the increase of the membrane rigidity. Binding of all ligands to the agonist-bound-like conformations is systematically stronger in comparison to antagonist-bound-likes ones. This is dramatically opposite to the results obtained for static crystal structures. Our results show that accounting for internal protein dynamics, strongly modulated by its lipid environment, is crucial for correct assessment of the ligand binding to P2Y12.
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BACKGROUND: Tenofovir disoproxil fumarate is a prodrug of tenofovir diphosphate that exposes patients to renal toxicity over the long term. Tenofovir alafenamide, a new prodrug, now makes it possible to reduce toxicity, but at the cost of an alteration in lipid profile. There is currently no recommendation for follow-up of lipid profile when switching from tenofovir disoproxil fumarate to tenofovir alafenamide. OBJECTIVE: Our study aimed to evaluate the effects on renal function and lipid profile of a switch from tenofovir disoproxil fumarate to tenofovir alafenamide, and the consequences for patient management. METHODS: Demographic, clinical and biological data was recorded from a retrospective clinical cohort study in real-life, including patients who switched from tenofovir disoproxil fumarate to tenofovir alafenamide. A descriptive analysis of the study population, with a comparison of biological parameters using the paired Student t test for paired data was performed. RESULTS: From January 2016 to January 2019, a total of 103 patients were included. There was no significant difference in renal function before vs after the switch in therapy (p=0.29 for creatinine, p=0.30 for phosphoremia). We observed a change in lipid profile, with a significant increase in total cholesterol (p=0.0006), HDL cholesterol (p=0.0055) and triglycerides (p=0.0242). Four patients received lipid-lowering therapy after switching. CONCLUSION: In patients who switch from tenofovir disoproxil fumarate to tenofovir alafenamide, lipid profile is altered, and may require initiation of lipid-lowering therapy. It seems necessary to monitor lipid parameters after this switch, despite the absence of an official recommendation.