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1.
Artigo em Inglês | MEDLINE | ID: mdl-38843105

RESUMO

RATIONALE: Idiopathic pulmonary fibrosis (IPF) is a rare and progressive disease, which causes progressive cough, exertional dyspnea, impaired quality of life and death. OBJECTIVES: Bexotegrast (PLN 74809) is an oral, once-daily, investigational drug in development for the treatment of IPF. METHODS: This Phase 2a, multicenter, clinical trial, randomized participants with IPF to receive oral, once daily bexotegrast 40 mg, 80 mg, 160 mg, 320 mg, or placebo, with or without background IPF therapy (pirfenidone or nintedanib), in an approximately 3:1 ratio in each bexotegrast dose cohort, for at least 12 weeks. The primary endpoint was incidence of treatment-emergent adverse events (TEAEs). Exploratory efficacy endpoints included change from baseline in forced vital capacity (FVC); quantitative lung fibrosis (QLF) extent (%) and changes from baseline in fibrosis-related biomarkers. MEASUREMENTS AND MAIN RESULTS: Bexotegrast was well tolerated with similar rates of TEAEs in the pooled bexotegrast and placebo groups (62/89 [69.7%] and 21/31 [67.7%], respectively). Diarrhea was the most common TEAE; most participants with diarrhea also received nintedanib. Bexotegrast treated participants experienced a reduction in FVC decline over 12 weeks vs. placebo, with or without background therapy. A dose-dependent antifibrotic effect of bexotegrast was observed with QLF imaging and a decrease in fibrosis-associated biomarkers was observed with bexotegrast vs. placebo. CONCLUSIONS: Bexotegrast demonstrated a favorable safety and tolerability profile, up to 12 weeks for the doses studied. Exploratory analyses suggest an antifibrotic effect according to FVC, QLF imaging, and circulating levels of fibrosis biomarkers. Clinical trial registration available at www. CLINICALTRIALS: gov, ID: NCT04396756. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

2.
J Hepatol ; 75(6): 1292-1300, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34454994

RESUMO

BACKGROUND & AIMS: The development of accurate non-invasive tests to detect and measure the extent of fibrosis and disease activity in patients with non-alcoholic steatohepatitis (NASH) - the progressive phenotype of non-alcoholic fatty liver disease (NAFLD) - is of great clinical importance. Herein, we aimed to validate the performance of PRO-C3 and ADAPT for the detection of moderate/severe fibrosis within the CENTAUR screening population. METHODS: PRO-C3 was assessed in plasma from the screening population of the phase IIb CENTAUR study (NCT02217475) in adults with NASH and liver fibrosis. The relation between PRO-C3 and histologic features of NASH was evaluated, as well as the demographics of patients with high and low levels of PRO-C3. The diagnostic ability of PRO-C3, as a standalone marker or incorporated into ADAPT, to identify patients with F≥2 and NASH was estimated using receiver-operating characteristic analysis and logistic regression models. RESULTS: A total of 517 individuals with matched biopsy and PRO-C3 measurements were included. Patients with PRO-C3 levels ≥20.2 ng/ml showed increased levels of insulin, HOMA-IR, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, and platelet count compared to patients with low PRO-C3 (p <0.05). PRO-C3 increased stepwise with increasing liver fibrosis, lobular inflammation, hepatocyte ballooning, steatosis, and NAFLD activity score (p <0.05), and could distinguish between NAFL and NASH (p <0.0001). PRO-C3 was independently associated with fibrosis and NASH when adjusted for clinical confounders. ADAPT outperformed Fibrosis-4, AST-to-platelet ratio index, and AST/ALT ratio as a predictor of advanced fibrosis and NASH (p <0.001). CONCLUSION: PRO-C3 was associated with NAFLD activity score and fibrosis. ADAPT outperformed other non-invasive scores for detecting NASH. These data support the use of PRO-C3 and ADAPT as diagnostic tools to identify patients with NASH eligible for inclusion in clinical trials. CLINICAL TRIAL NUMBER: NCT02217475 LAY SUMMARY: PRO-C3 is a serological biomarker associated with liver disease activity and fibrosis. Its performance for the detection of disease activity and fibrosis is improved when it is incorporated into the ADAPT score. Herein, we showed that ADAPT was better at selecting patients with non-alcoholic steatohepatitis for inclusion in clinical trials than other non-invasive scores.


Assuntos
Biomarcadores/análise , Cirrose Hepática/diagnóstico , Área Sob a Curva , Biomarcadores/sangue , Biópsia/métodos , Biópsia/estatística & dados numéricos , Complemento C3/análise , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/fisiopatologia , Modelos Logísticos , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença
3.
Respir Res ; 22(1): 265, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34666752

RESUMO

RATIONALE: αv integrins, key regulators of transforming growth factor-ß activation and fibrogenesis in in vivo models of pulmonary fibrosis, are expressed on abnormal epithelial cells (αvß6) and fibroblasts (αvß1) in fibrotic lungs. OBJECTIVES: We evaluated multiple αv integrin inhibition strategies to assess which most effectively reduced fibrogenesis in explanted lung tissue from patients with idiopathic pulmonary fibrosis. METHODS: Selective αvß6 and αvß1, dual αvß6/αvß1, and multi-αv integrin inhibitors were characterized for potency, selectivity, and functional activity by ligand binding, cell adhesion, and transforming growth factor-ß cell activation assays. Precision-cut lung slices generated from lung explants from patients with idiopathic pulmonary fibrosis or bleomycin-challenged mouse lungs were treated with integrin inhibitors or standard-of-care drugs (nintedanib or pirfenidone) and analyzed for changes in fibrotic gene expression or TGF-ß signaling. Bleomycin-challenged mice treated with dual αvß6/αvß1 integrin inhibitor, PLN-74809, were assessed for changes in pulmonary collagen deposition and Smad3 phosphorylation. MEASUREMENTS AND MAIN RESULTS: Inhibition of integrins αvß6 and αvß1 was additive in reducing type I collagen gene expression in explanted lung tissue slices from patients with idiopathic pulmonary fibrosis. These data were replicated in fibrotic mouse lung tissue, with no added benefit observed from inhibition of additional αv integrins. Antifibrotic efficacy of dual αvß6/αvß1 integrin inhibitor PLN-74809 was confirmed in vivo, where dose-dependent inhibition of pulmonary Smad3 phosphorylation and collagen deposition was observed. PLN-74809 also, more potently, reduced collagen gene expression in fibrotic human and mouse lung slices than clinically relevant concentrations of nintedanib or pirfenidone. CONCLUSIONS: In the fibrotic lung, dual inhibition of integrins αvß6 and αvß1 offers the optimal approach for blocking fibrogenesis resulting from integrin-mediated activation of transforming growth factor-ß.


Assuntos
Antifibróticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Integrina alfa6beta1/antagonistas & inibidores , Pulmão/efeitos dos fármacos , Receptores de Vitronectina/antagonistas & inibidores , Animais , Bleomicina , Linhagem Celular , Técnicas de Cocultura , Cadeia alfa 1 do Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Integrina alfa6beta1/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Fosforilação , Receptores de Vitronectina/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo
4.
J Neuroinflammation ; 17(1): 296, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33036616

RESUMO

BACKGROUND: Chronic alcohol consumption is associated with neuroinflammation, neuronal damage, and behavioral alterations including addiction. Alcohol-induced neuroinflammation is characterized by increased expression of proinflammatory cytokines (including TNFα, IL-1ß, and CCL2) and microglial activation. We hypothesized chronic alcohol consumption results in peripheral immune cell infiltration to the CNS. Since chemotaxis through the CCL2-CCR2 signaling axis is critical for macrophage recruitment peripherally and centrally, we further hypothesized that blockade of CCL2 signaling using the dual CCR2/5 inhibitor cenicriviroc (CVC) would prevent alcohol-induced CNS infiltration of peripheral macrophages and alter the neuroinflammatory state in the brain after chronic alcohol consumption. METHODS: C57BL/6J female mice were fed an isocaloric or 5% (v/v) ethanol Lieber DeCarli diet for 6 weeks. Some mice received daily injections of CVC. Microglia and infiltrating macrophages were characterized and quantified by flow cytometry and visualized using CX3CR1eGFP/+ CCR2RFP/+ reporter mice. The effect of ethanol and CVC treatment on the expression of inflammatory genes was evaluated in various regions of the brain, using a Nanostring nCounter inflammation panel. Microglia activation was analyzed by immunofluorescence. CVC-treated and untreated mice were presented with the two-bottle choice test. RESULTS: Chronic alcohol consumption induced microglia activation and peripheral macrophage infiltration in the CNS, particularly in the hippocampus. Treatment with CVC abrogated ethanol-induced recruitment of peripheral macrophages and partially reversed microglia activation. Furthermore, the expression of proinflammatory markers was upregulated by chronic alcohol consumption in various regions of the brain, including the cortex, hippocampus, and cerebellum. Inhibition of CCR2/5 decreased alcohol-mediated expression of inflammatory markers. Finally, microglia function was impaired by chronic alcohol consumption and restored by CVC treatment. CVC treatment did not change the ethanol consumption or preference of mice in the two-bottle choice test. CONCLUSIONS: Together, our data establish that chronic alcohol consumption promotes the recruitment of peripheral macrophages into the CNS and microglia alterations through the CCR2/5 axis. Therefore, further exploration of the CCR2/5 axis as a modulator of neuroinflammation may offer a potential therapeutic approach for the treatment of alcohol-associated neuroinflammation.


Assuntos
Encéfalo/metabolismo , Etanol/toxicidade , Macrófagos/metabolismo , Microglia/metabolismo , Receptores CCR2/metabolismo , Receptores CCR5/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Antagonistas dos Receptores CCR5/farmacologia , Etanol/administração & dosagem , Feminino , Imidazóis/farmacologia , Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Receptores CCR2/antagonistas & inibidores , Sulfóxidos/farmacologia
5.
Hepatology ; 69(3): 1105-1121, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30179264

RESUMO

Kupffer cell and macrophage (MØ) activation contributes to steatosis, inflammation, and fibrosis in alcoholic liver disease (ALD). We found increased frequency of MØ, T cells, and expression of C-C chemokine receptor type 2 (Ccr2) and C-C chemokine receptor type 5 (Ccr5) in the livers of patients with ALD, and increased circulating chemokines, C-C chemokine ligand types 2 (CCL2), and C-C chemokine ligand types 5 (CCL5) in patients with alcoholic hepatitis. We hypothesized that inhibition of CCL2 signaling with the dual CCR2/5 inhibitor, cenicriviroc (CVC), would attenuate ALD. In a mouse model of ALD, liver injury (alanine aminotransferase [ALT]) and steatosis were prevented by CVC whether administered as "prevention" throughout the alcohol feeding or as "treatment" started after the development of ALD. Alcohol-induced increases in early liver fibrosis markers (sirius red, hydroxyproline, and collagen-1) were normalized by both modes of CVC administration. We found that prevention and treatment with CVC reversed alcohol-related increases in liver mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and CCL2. CVC administration regimens prevented the increase in infiltrating MØ (F4/80lo CD11bhi ) and reduced proinflammatory Ly6Chi MØ in livers of alcohol-fed mice. CVC increased liver T-cell numbers and attenuated Il-2 expression without an effect on CD69+ or CD25+ T-cell expression. In vitro, CVC inhibited CCL2-induced increases in hepatocyte fatty acid synthase (Fasn) and adipose differentiation-related protein (Adrp), whereas it augmented acyl-coenzyme A oxidase 1 (Acox-1), proliferator-activated receptor gamma co-activator alpha (Pgc1α) and uncoupling protein 2 expression, suggesting mechanisms for attenuated hepatocyte steatosis. We found that CCL2 and CCL5 sensitized hepatocytes to lipopolysaccharide-induced liver injury (TNF-α, ALT, and lactate dehydrogenase release). Alcohol feeding induced apoptosis (poly ADP-ribose polymerase [PARP] and caspase-3 [CASP-3] cleavage) and pyroptosis (gasdermin D [GSDMD] cleavage) in livers, and CVC prevented both of these forms of cell death. Conclusion: Together, our data demonstrate preclinical evidence for CCR2/CCR5 inhibition with CVC as a potent intervention to ameliorate alcohol-induced steatohepatitis and liver damage.


Assuntos
Antagonistas dos Receptores CCR5/uso terapêutico , Hepatopatias Alcoólicas/tratamento farmacológico , Receptores CCR2/antagonistas & inibidores , Animais , Fígado Gorduroso Alcoólico/tratamento farmacológico , Feminino , Hepatite Alcoólica/tratamento farmacológico , Cirrose Hepática Alcoólica/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos
6.
Sensors (Basel) ; 20(14)2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32674328

RESUMO

Monitoring the evolution of snow on the ground and lake ice-two of the most important components of the changing northern environment-is essential. In this paper, we describe a lightweight, compact and autonomous 24 GHz frequency-modulated continuous-wave (FMCW) radar system for freshwater ice thickness and snow mass (snow water equivalent, SWE) measurements. Although FMCW radars have a long-established history, the novelty of this research lies in that we take advantage the availability of a new generation of low cost and low power requirement units that facilitates the monitoring of snow and ice at remote locations. Test performance (accuracy and limitations) is presented for five different applications, all using an automatic operating mode with improved signal processing: (1) In situ lake ice thickness measurements giving 2 cm accuracy up to ≈1 m ice thickness and a radar resolution of 4 cm; (2) remotely piloted aircraft-based lake ice thickness from low-altitude flight at 5 m; (3) in situ dry SWE measurements based on known snow depth, giving 13% accuracy (RMSE 20%) over boreal forest, subarctic taiga and Arctic tundra, with a measurement capability of up to 3 m in snowpack thickness; (4) continuous monitoring of surface snow density under particular Antarctic conditions; (5) continuous SWE monitoring through the winter with a synchronized and collocated snow depth sensor (ultrasonic or LiDAR sensor), giving 13.5% bias and 25 mm root mean square difference (RMSD) (10%) for dry snow. The need for detection processing for wet snow, which strongly absorbs radar signals, is discussed. An appendix provides 24 GHz simulated effective refractive index and penetration depth as a function of a wide range of density, temperature and wetness for ice and snow.

7.
Clin Gastroenterol Hepatol ; 17(4): 616-629.e26, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29913275

RESUMO

BACKGROUND & AIMS: It is important to know the extent of the placebo effect in designing randomized controlled trials for patients with nonalcoholic steatohepatitis (NASH), to accurately calculate sample size and define treatment endpoints. METHODS: We performed a systematic review and meta-analysis of the placebo groups from randomized controlled trials of adults with NASH that provided histologic and/or magnetic resonance image-based assessments. We identified trials through a comprehensive search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Scopus, from each database's inception through January 2, 2018. RESULTS: We identified 39 randomized controlled trials, comprising 1463 patients who received placebo. Histologic assessment data (the nonalcoholic fatty liver disease activity scores, NAS) were available from 956 patients; magnetic resonance spectroscopy data were available from 295 patients and magnetic resonance proton density fat fraction measurements from 61 patients. Overall, 25% of patients given placebo had an improvement in NAS by 2 or more points (95% CI, 21%-29%) with a small amount of heterogeneity (I2 = 27%). There were improvements by at least 1 point in steatosis scores of 33% ± 3% of patients, in hepatocyte ballooning scores of 30% ± 3% of patients, in lobular inflammation scores of 32% ± 3% of patients, and in fibrosis scores of 21% ± 3% of patients, with a moderate amount of heterogeneity among trials (I2 range, 51%-63%). Patients given placebo had a statistically significant improvement in NAS (by 0.72 ± 0.19), with a large amount of heterogeneity (I2 = 96%). Univariate and multivariate meta-regression showed that trials with a higher baseline NAS, those conducted in South America, and those in which patients had a decrease in body mass index, were associated with greater improvements in NAS among patients given placebo. Patients given placebo had significant reductions in intrahepatic triglyceride, measured by magnetic resonance spectroscopy (by 1.45% ± 0.54%) with moderate heterogeneity (I2 = 40%), and in magnetic resonance proton density fat fraction (by 2.43 ± 0.89), without heterogeneity (I2 = 0). Mean serum levels of alanine and aspartate aminotransferases decreased significantly (by 11.7 ± 3.8 U/L and 5.9 ± 2.1 U/L, respectively; P < .01 for both). CONCLUSIONS: In a meta-analysis of randomized controlled trials of NASH, patients given placebo have significant histologic, radiologic, and biochemical responses. The placebo response should be considered in designing trials of agents for treatment of NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Efeito Placebo , Placebos/administração & dosagem , Placebos/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Bioestatística/métodos , Humanos , América do Sul , Resultado do Tratamento
8.
Hepatology ; 67(4): 1270-1283, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28940700

RESUMO

Macrophages are key regulators of liver fibrosis progression and regression in nonalcoholic steatohepatitis (NASH). Liver macrophages comprise resident phagocytes, Kupffer cells, and monocyte-derived cells, which are recruited through the chemokine receptor C-C motif chemokine receptor 2 (CCR2). We aimed at elucidating the therapeutic effects of inhibiting monocyte infiltration in NASH models by using cenicriviroc (CVC), an oral dual chemokine receptor CCR2/CCR5 antagonist that is under clinical evaluation. Human liver tissues from NASH patients were analyzed for CCR2+ macrophages, and administration of CVC was tested in mouse models of steatohepatitis, liver fibrosis progression, and fibrosis regression. In human livers from 17 patients and 4 controls, CCR2+ macrophages increased parallel to NASH severity and fibrosis stage, with a concomitant inflammatory polarization of these cluster of differentiation 68+ , portal monocyte-derived macrophages (MoMF). Similar to human disease, we observed a massive increase of hepatic MoMF in experimental models of steatohepatitis and liver fibrosis. Therapeutic treatment with CVC significantly reduced the recruitment of hepatic Ly-6C+ MoMF in all models. In experimental steatohepatitis with obesity, therapeutic CVC application significantly improved insulin resistance and hepatic triglyceride levels. In fibrotic steatohepatitis, CVC treatment ameliorated histological NASH activity and hepatic fibrosis. CVC inhibited the infiltration of Ly-6C+ monocytes, without direct effects on macrophage polarization, hepatocyte fatty acid metabolism, or stellate cell activation. Importantly, CVC did not delay fibrosis resolution after injury cessation. RNA sequencing analysis revealed that MoMF, but not Kupffer cells, specifically up-regulate multiple growth factors and cytokines associated with fibrosis progression, while Kupffer cells activated pathways related to inflammation initiation and lipid metabolism. CONCLUSION: Pharmacological inhibition of CCR2+ monocyte recruitment efficiently ameliorates insulin resistance, hepatic inflammation, and fibrosis, corroborating the therapeutic potential of CVC in patients with NASH. (Hepatology 2018;67:1270-1283).


Assuntos
Antagonistas dos Receptores CCR5/farmacologia , Imidazóis/farmacologia , Cirrose Hepática/tratamento farmacológico , Monócitos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Adulto , Idoso , Animais , Quimiotaxia de Leucócito/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Resistência à Insulina , Fígado/patologia , Cirrose Hepática/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Monócitos/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Sulfóxidos
9.
Hepatology ; 67(5): 1754-1767, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28833331

RESUMO

The aim of this study was to evaluate cenicriviroc (CVC), a dual antagonist of CC chemokine receptor types 2 and 5, for treatment of nonalcoholic steatohepatitis (NASH) with liver fibrosis (LF). A randomized, double-blind, multinational phase 2b study enrolled subjects with NASH, a nonalcoholic fatty liver disease activity score (NAS) ≥4, and LF (stages 1-3, NASH Clinical Research Network) at 81 clinical sites. Subjects (N = 289) were randomly assigned CVC 150 mg or placebo. Primary outcome was ≥2-point improvement in NAS and no worsening of fibrosis at year 1. Key secondary outcomes were: resolution of steatohepatitis (SH) and no worsening of fibrosis; improvement in fibrosis by ≥1 stage and no worsening of SH. Biomarkers of inflammation and adverse events were assessed. Full study recruitment was achieved. The primary endpoint of NAS improvement in the intent-to-treat population and resolution of SH was achieved in a similar proportion of subjects on CVC (N = 145) and placebo (N = 144; 16% vs. 19%, P = 0.52 and 8% vs. 6%, P = 0.49, respectively). However, the fibrosis endpoint was met in significantly more subjects on CVC than placebo (20% vs. 10%; P = 0.02). Treatment benefits were greater in those with higher disease activity and fibrosis stage at baseline. Biomarkers of systemic inflammation were reduced with CVC. Safety and tolerability of CVC were comparable to placebo. CONCLUSION: After 1 year of CVC treatment, twice as many subjects achieved improvement in fibrosis and no worsening of SH compared with placebo. Given the urgent need to develop antifibrotic therapies in NASH, these findings warrant phase 3 evaluation. (Hepatology 2018;67:1754-1767).


Assuntos
Antagonistas dos Receptores CCR5/uso terapêutico , Imidazóis/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Adulto , Idoso , Biomarcadores/sangue , Antagonistas dos Receptores CCR5/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Imidazóis/efeitos adversos , Fígado/patologia , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Sulfóxidos , Resultado do Tratamento
10.
Hepatology ; 64(5): 1667-1682, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27302828

RESUMO

Acetaminophen (APAP, paracetamol) poisoning is a leading cause of acute liver failure (ALF) in humans and induces hepatocyte necrosis, followed by activation of the innate immune system, further aggravating liver injury. The role of infiltrating monocytes during the early phase of ALF is still ambiguous. Upon experimental APAP overdose in mice, monocyte-derived macrophages (MoMFs) massively accumulated in injured liver within 12-24 hours, whereas the number of tissue-resident macrophages (Kupffer cells) decreased. Influx of MoMFs is dependent on the chemokine receptor, chemokine (C-C motif) receptor 2 (CCR2), given that Ccr2-/- mice display reduced infiltration of monocytes and attenuated liver injury post-APAP overdose at early time points. As evidenced by intravital multiphoton microscopy of Ccr2 reporter mice, CCR2+ monocytes infiltrate liver as early as 8-12 hours post-APAP overdose and form dense cellular clusters around necrotic areas. CCR2+ MoMFs express a distinct pattern of inflammatory, but also repair-associated, genes in injured livers. Adoptive transfer experiments revealed that MoMFs primarily exert proinflammatory functions early post-APAP, thereby aggravating liver injury. Consequently, early pharmacological inhibition of either chemokine (C-C motif) ligand (CCL2; by the inhibitor, mNOX-E36) or CCR2 (by the orally available dual CCR2/CCR5 inhibitor, cenicriviroc) reduces monocyte infiltration and APAP-induced liver injury (AILI) in mice. Importantly, neither the early nor continuous inhibition of CCR2 hinder repair processes during resolution from injury. In line with this, human livers of ALF patients requiring liver transplantation reveal increased CD68+ hepatic macrophage numbers with massive infiltrates of periportal CCR2+ macrophages that display a proinflammatory polarization. CONCLUSION: Infiltrating monocyte-derived macrophages aggravate APAP hepatotoxicity, and the pharmacological inhibition of either CCL2 or CCR2 might bear therapeutic potential by reducing the inflammatory reaction during the early phase of AILI. (Hepatology 2016;64:1667-1682).


Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Antipiréticos/efeitos adversos , Falência Hepática Aguda/induzido quimicamente , Receptores CCR2/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/química , Receptores CCR2/análise , Índice de Gravidade de Doença
11.
J Antimicrob Chemother ; 70(3): 750-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25433008

RESUMO

OBJECTIVES: Cenicriviroc is a potent antagonist of the chemokine coreceptors 5 and 2 (CCR5/CCR2) and blocks HIV-1 entry. The CCR5 inhibitor maraviroc has been shown in tissue culture to be able to repel cell-free virions from the cell surface into extracellular space. We hypothesized that cenicriviroc might exhibit a similar effect, and tested this using clinical samples from the Phase IIb study 652-2-202, by measuring rates of intracellular DNA decline. We also monitored viral RNA levels in culture fluids. METHODS: We infected PM-1 cells with CCR5-tropic HIV-1 BaL in the presence or absence of inhibitory concentrations of cenicriviroc (20 nM) or maraviroc (50 nM) or controls. Viral load levels and p24 were measured by ELISA, quantitative PCR and quantitative real-time reverse transcription PCR at 4 h post-infection. Frozen PBMC DNA samples from 30 patients with virological success in the Phase IIb study were studied, as were early and late reverse transcript levels. Docking studies compared binding between cenicriviroc/CCR5 and maraviroc/CCR5. RESULTS: Unlike maraviroc, cenicriviroc did not cause an increase in the amount of virus present in culture fluids at 4 h compared with baseline. The use of cenicriviroc did, however, result in lower levels of intracellular viral DNA after 4 h. Structural modelling indicates that cenicriviroc binds more deeply than maraviroc to the hydrophobic pocket of CCR5, providing an explanation for the absence of viral rebound with cenicriviroc. CONCLUSIONS: In contrast to maraviroc, cenicriviroc does not repel virus back into extracellular space. Differences in results may be due to superior binding of cenicriviroc to CCR5 compared with maraviroc.


Assuntos
Fármacos Anti-HIV/farmacologia , DNA Viral/análise , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Imidazóis/farmacologia , Carga Viral , Fármacos Anti-HIV/uso terapêutico , Linhagem Celular , Ensaios Clínicos Fase II como Assunto , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Espaço Extracelular/virologia , Infecções por HIV/tratamento farmacológico , Humanos , Imidazóis/uso terapêutico , Leucócitos Mononucleares/virologia , Reação em Cadeia da Polimerase em Tempo Real , Sulfóxidos , Cultura de Vírus
13.
Ann Surg ; 254(4): 598-605, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21918426

RESUMO

OBJECTIVE: To determine whether implementation of damage control resuscitation (DCR) in patients undergoing damage control laparotomy (DCL) translates into improved survival. BACKGROUND: DCR aims at preventing coagulopathy through permissive hypotension, limiting crystalloids and delivering higher ratios of plasma and platelets. Previous work has focused only on the impact of delivering higher ratios (1:1:1). METHODS: A retrospective cohort study was performed on all DCL patients admitted between January 2004 and August 2010. Patients were divided into pre-DCR implementation and DCR groups and were excluded if they died before completion of the initial laparotomy. The lethal triad was defined as immediate postoperative temperature less than 95°F, international normalized ratio more than 1.5, or a pH less than 7.30. RESULTS: A total of 390 patients underwent DCL. Of these, 282 were pre-DCR and 108 were DCR. Groups were similar in demographics, injury severity, admission vitals, and laboratory values. DCR patients received less crystalloids (median: 14 L vs 5 L), red blood cells (13 U vs 7 U), plasma (11 U vs 8 U), and platelets (6 U vs 0 U) in 24 hours, all P < 0.05. DCR patients had less evidence of the lethal triad upon intensive care unit arrival (80% vs 46%, P < 0.001). 24-hour and 30-day survival was higher with DCR (88% vs 97%, P = 0.006 and 76% vs 86%, P = 0.03). Multivariate analysis controlling for age, injury severity, and emergency department variables, demonstrated DCR was associated with a significant increase in 30-day survival (OR: 2.5, 95% CI: 1.10-5.58, P = 0.028). CONCLUSION: In patients undergoing DCL, implementation of DCR reduces crystalloid and blood product administration. More importantly, DCR is associated with an improvement in 30-day survival.


Assuntos
Hemorragia/mortalidade , Hemorragia/terapia , Laparotomia , Ressuscitação , Ferimentos e Lesões/complicações , Ferimentos e Lesões/cirurgia , Adulto , Estudos de Coortes , Feminino , Hemorragia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
14.
Ann Emerg Med ; 68(1): 40-2, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26707357
15.
Hepatol Commun ; 5(3): 478-490, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33681680

RESUMO

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disease with no approved treatments. C-C chemokine receptor types 2 and 5 (CCR2/CCR5) play an important role in inflammation and fibrosis and are potential therapeutic targets for PSC. We evaluated the efficacy and safety of cenicriviroc (CVC), a dual antagonist of CCR2 and CCR5, for the treatment of PSC. This was a single-arm, open-label, exploratory study of CVC in adults with a clinical diagnosis of PSC, serum alkaline phosphatase (ALP) ≥1.5 times the upper limit of normal (ULN), with or without inflammatory bowel disease, across eight sites in the United States and Canada. The primary endpoint was percent change in ALP over 24 weeks; key secondary efficacy endpoints were proportion of participants who achieved ALP normalization and overall response (decrease to <1.5 times the ULN or 50% decrease). Of the 24 participants, 20 completed the study. The mean age was 43 years, 50% were female, and the mean body mass index was 25 kg/m2. From a median ALP baseline of 369 U/L (range: 173, 1,377 U/L), a median absolute reduction of 49.5 U/L (range: -460, 416 U/L) was achieved at week 24, corresponding to a median reduction of 18.0% (range: -46%, 89%). No participant achieved ALP normalization or a 50% decrease; 2 participants (10%) achieved a reduction in ALP to < 1.5 times the ULN, and 4 had ≥25% increase. Twenty participants (83.3%) reported at least one adverse event; most were mild to moderate in severity. The most frequent events were rash, fatigue, and dizziness. Conclusion: After 24 weeks of CVC treatment, adults with PSC achieved a modest reduction (median 18%) in the surrogate endpoint of ALP. CVC was well tolerated, and no new safety signals were observed. ClinicalTrials.gov identifier: NCT02653625.


Assuntos
Colangite Esclerosante/tratamento farmacológico , Imidazóis/uso terapêutico , Sulfóxidos/uso terapêutico , Adolescente , Adulto , Idoso , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Canadá , Colangite Esclerosante/sangue , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Estados Unidos , Adulto Jovem
16.
Science ; 372(6546): 1097-1101, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083489

RESUMO

Water-stable isotopes in polar ice cores are a widely used temperature proxy in paleoclimate reconstruction, yet calibration remains challenging in East Antarctica. Here, we reconstruct the magnitude and spatial pattern of Last Glacial Maximum surface cooling in Antarctica using borehole thermometry and firn properties in seven ice cores. West Antarctic sites cooled ~10°C relative to the preindustrial period. East Antarctic sites show a range from ~4° to ~7°C cooling, which is consistent with the results of global climate models when the effects of topographic changes indicated with ice core air-content data are included, but less than those indicated with the use of water-stable isotopes calibrated against modern spatial gradients. An altered Antarctic temperature inversion during the glacial reconciles our estimates with water-isotope observations.

17.
Intervirology ; 53(3): 176-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20197684

RESUMO

OBJECTIVE: To investigate the potential for a pharmacokinetic interaction between darunavir (DRV, TMC114, Prezista), indinavir (IDV, Crixivan) and low-dose ritonavir (RTV, Norvir). METHODS: In three 7-day sessions, 17 HIV-negative healthy volunteers received treatment A (DRV/r 400/100 mg b.i.d.), treatment B (IDV/r 800/100 mg b.i.d.) and treatment C (DRV/r 400/100 mg b.i.d. + IDV 800 mg b.i.d.). On day 7, full pharmacokinetic profiles of DRV, IDV and RTV were determined. Safety and tolerability were also assessed. RESULTS: Based on the least-squares means ratios, the steady-state exposure (area under the curve, AUC(12h)) and plasma concentrations (C(min) and C(max)) of IDV were increased by 23, 125 and 8%, respectively, when DRV was co-administered. The co-administration of IDV with DRV/r resulted in increases of 24, 44 and 11% for, respectively, DRV AUC(12h), C(min) and C(max), compared with administration of DRV/r alone. Eight volunteers discontinued due to an adverse event. Overall, adverse events and laboratory abnormalities were more commonly reported during treatments including IDV. CONCLUSIONS: When used in combination with DRV/r, dose adjustment of IDV from 800 mg b.i.d. to 600 mg b.i.d. may be warranted in cases of intolerance.


Assuntos
Fármacos Anti-HIV/farmacocinética , Indinavir/farmacocinética , Ritonavir/farmacocinética , Sulfonamidas/farmacocinética , Adulto , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/efeitos adversos , Darunavir , Interações Medicamentosas , Feminino , Voluntários Saudáveis , Humanos , Indinavir/administração & dosagem , Indinavir/efeitos adversos , Masculino , Plasma/química , Ritonavir/administração & dosagem , Ritonavir/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Adulto Jovem
18.
Br J Clin Pharmacol ; 68(1): 116-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19660009

RESUMO

AIM: To investigate the pharmacokinetic interaction between darunavir/ritonavir (DRV/r) and nevirapine (NVP) in 19 HIV-infected patients. METHODS: An open-label, randomized, crossover study. Patients received Treatment A [NVP 200 mg b.i.d. plus > or =2 nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs)] and Treatment B [A plus DRV/r 300/100 mg b.i.d. (DRV oral solution)] or Treatment B2 [A plus DRV/r 400/100 mg b.i.d. (DRV tablet)] in two 14-day sessions. RESULTS: Mean NVP AUC(12h) increased by 27% [least square means ratio 1.27 (95% confidence interval 1.02, 1.58)]. Mean DRV and ritonavir exposures were similar to historical data. Co-administration was well tolerated. CONCLUSIONS: DRV/r and NVP have no clinically relevant interaction. No dose adjustments are required.


Assuntos
Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/administração & dosagem , Nevirapina/administração & dosagem , Inibidores da Transcriptase Reversa/administração & dosagem , Ritonavir/administração & dosagem , Sulfonamidas/administração & dosagem , Adulto , Estudos Cross-Over , Darunavir , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Inibidores da Protease de HIV/farmacocinética , HIV-1/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nevirapina/farmacocinética , Inibidores da Transcriptase Reversa/farmacocinética , Ritonavir/farmacocinética , Sulfonamidas/farmacocinética , Resultado do Tratamento
19.
AIDS Rev ; 10(3): 131-42, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18820715

RESUMO

The current effectiveness of HAART in the management of HIV infection is compromised by the emergence of extensively cross-resistant strains of HIV-1, requiring a significant need for new therapeutic agents. Due to its crucial role in viral maturation and therefore HIV-1 replication and infectivity, the HIV-1 protease continues to be a major development target for antiretroviral therapy. However, new protease inhibitors must have higher thresholds to the development of resistance and cross-resistance. Research has demonstrated that the binding characteristics between a protease inhibitor and the active site of the HIV-1 protease are key factors in the development of resistance. More specifically, the way in which a protease inhibitor fits within the substrate consensus volume, or "substrate envelope", appears to be critical. The currently available inhibitors are not only smaller than the native substrates, but also have a different shape. This difference in shape underlies observed patterns of resistance because primary drug-resistant mutations often arise at positions in the protease where the inhibitors protrude beyond the substrate envelope but are still in contact with the enzyme. Since all currently available protease inhibitors occupy a similar space (in spite of their structural differences) in the active site of the enzyme, the specific positions where the inhibitors protrude and contact the enzyme correspond to the locations where most mutations occur that give rise to multidrug-resistant HIV-1 strains. Detailed investigation of the structure, thermodynamics, and dynamics of the active site of the protease enzyme is enabling the identification of new protease inhibitors that more closely fit within the substrate envelope and therefore decrease the risk of drug resistance developing. The features of darunavir, the latest FDA-approved protease inhibitor, include its high binding affinity (Kd = 4.5 x 10-12 M) for the protease active site, the presence of hydrogen bonds with the backbone, and its ability to fit closely within the substrate envelope (or consensus volume). Darunavir is potent against both wild-type and protease inhibitor-resistant viruses in vitro, including a broad range of over 4,000 clinical isolates. Additionally, in vitro selection studies with wild-type HIV-1 strains have shown that resistance to darunavir develops much more slowly and is more difficult to generate than for existing protease inhibitors. Clinical studies have shown that darunavir administered with low-dose ritonavir (darunavir/ritonavir) provides highly potent viral suppression (including significant decreases in HIV viral load in patients with documented protease inhibitor resistance) together with favorable tolerability. In conclusion, as a result of its high binding affinity for and overall fit within the active site of HIV-1 protease, darunavir has a higher genetic barrier to the development of resistance and better clinical efficacy against multidrug-resistant HIV relative to current protease inhibitors. The observed efficacy, safety and tolerability of darunavir in highly treatment-experienced patients makes darunavir an important new therapeutic option for HIV-infected patients.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/farmacologia , Protease de HIV/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Sulfonamidas/farmacologia , Ensaios Clínicos como Assunto , Darunavir , Infecções por HIV/virologia , Protease de HIV/química , Protease de HIV/genética , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/química , Inibidores da Protease de HIV/uso terapêutico , HIV-1/enzimologia , HIV-1/genética , Humanos , Modelos Moleculares , Ritonavir/administração & dosagem , Ritonavir/uso terapêutico , Relação Estrutura-Atividade , Especificidade por Substrato , Sulfonamidas/administração & dosagem , Sulfonamidas/química , Sulfonamidas/uso terapêutico , Resultado do Tratamento
20.
Antivir Ther ; 13(4): 563-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18672535

RESUMO

BACKGROUND: An open-label, randomized, crossover study was performed to investigate the effect of multiple doses of darunavir co-administered with low-dose ritonavir (DRV/r) on the steady-state pharmacokinetics of the oral contraceptives ethinyl estradiol (EE) and norethindrone (NE) (commercial name of the combined drug Ortho-Novum 1/35) in 19 HIV-negative healthy women. METHODS: In session 1, participants received 35 microg EE and 1.0 mg NE from days 1 to 21. In session 2, participants received the same oral contraceptive treatment as in session 1 on days 1 to 21 plus DRV/r (600 mg/100 mg twice daily) on days 1 to 14. Pharmacokinetic assessments were performed on day 14 for each session. RESULTS: Steady-state systemic exposure to EE and NE decreased when DRV/r was co-administered, based on the ratio of least square means of the minimum plasma concentration (Cmin), the maximum plasma concentration (Cmax), and the area under the curve (AUC24h) of EE (which decreased by 62%, 32% and 44%, respectively) and NE (which decreased by 30%, 10% and 14%, respectively) compared with administration of EE and NE alone. Five participants discontinued the study due to grade 2 cutaneous events, as required per protocol, during treatment with EE and NE in combination with DRV/r. There were no clinically relevant findings for laboratory and cardiovascular parameters. CONCLUSIONS: The pharmacokinetic interaction observed here is considered to be clinically relevant as EE concentrations are considerably reduced when DRV/r is co-administered with EE and NE. Alternative or additional contraceptive measures should be used when oestrogen-based contraceptives are co-administered with DRV/r.


Assuntos
Anticoncepcionais Orais/farmacocinética , Etinilestradiol/farmacocinética , Inibidores da Protease de HIV/farmacocinética , Noretindrona/farmacocinética , Ritonavir/farmacocinética , Sulfonamidas/farmacocinética , Adolescente , Adulto , Anticoncepcionais Orais/efeitos adversos , Estudos Cross-Over , Darunavir , Interações Medicamentosas , Quimioterapia Combinada , Etinilestradiol/administração & dosagem , Etinilestradiol/efeitos adversos , Feminino , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/efeitos adversos , Soronegatividade para HIV , Humanos , Noretindrona/administração & dosagem , Noretindrona/efeitos adversos , Ritonavir/administração & dosagem , Ritonavir/efeitos adversos , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos
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