33 research outputs found
Novel o-naphthoquinones induce apoptosis of EL-4 T lymphoma cells through the increase of reactive oxygen species
Novel β-lapachone analogs 2-phenyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione (NQ1), 2-p-tolyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione (NQ3) and 2-methyl-2-phenyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione (NQ7), which have trypanocidal activity, were assayed for cytotoxic effects on murine EL-4 T lymphoma cells. The NQs inhibited the proliferation of EL-4 cells at concentrations above 1 μM. Nuclear staining of the EL-4 cells revealed chromatin condensation and a nuclear morphology compatible with the induction of apoptosis. Flow cytometry assays with annexin V-FITC and propidium iodide confirmed the cell death by apoptosis. Using electron paramagnetic resonance (EPR), a semiquinone radical was detected in EL-4 cells treated with NQs. In addition, a decrease in the GSH level in parallel with reactive oxygen species (ROS) production was observed. Preincubation with n-acetyl-l-cysteine (NAC) was able to reverse the inhibitory effects of the NQs on cell proliferation, indicating that ROS generation is involved in NQ-induced apoptosis. In addition, the NQs induced a decrease in the mitochondrial membrane potential and increased the proteolytic activation of caspases 9 and 3 and the cleavage of Poly (ADP-Ribose) Polymerase (PARP). In conclusion, these results indicate that redox cycling is induced by the NQs in the EL-4 cell line, with the generation of ROS and other free radicals that could inhibit cellular proliferation as a result of the induction of the intrinsic apoptosis pathway.Fil: Di Rosso, MarÃa Emilia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Barreiro Arcos, MarÃa Laura. Universidad Catolica Argentina; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Elingold, Igal. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Sterle, Helena Andrea. Pontificia Universidad Católica Argentina "Santa MarÃa de Los Buenos Aires"; ArgentinaFil: Ferreira, Sabrina Baptista. Universidade Federal Do Rio de Janeiro; BrasilFil: Ferreira, Vitor Francisco. Universidade Federal Fluminense; BrasilFil: Galleano, Monica Liliana. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de BioquÃmica y Medicina Molecular; ArgentinaFil: Cremaschi, Graciela Alicia. Pontificia Universidad Católica Argentina "Santa MarÃa de Los Buenos Aires"; ArgentinaFil: Dubin, Marta. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentin
A hybrid of 1-deoxynojirimycin and benzotriazole induces preferential inhibition of butyrylcholinesterase (BuChE) over acetylcholinesterase (AChE)
The synthesis of four heterodimers in which the copper(I)-catalysed azide-alkyne cycloaddition was employed to connect a 1-deoxynojirimycin moiety with a benzotriazole scaffold is reported. The heterodimers were investigated as inhibitors against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The heterodimers displayed preferential inhibition (> 9) of BuChE over AChE in the micromolar concentration range (IC50 = 7–50 µM). For the most potent inhibitor of BuChE, Cornish-Bowden plots were used, which demonstrated that it behaves as a mixed inhibitor. Modelling studies of the same inhibitor demonstrated that the benzotriazole and 1-deoxynojirimycin moiety is accommodated in the peripheral anionic site and catalytic anionic site, respectively, of AChE. The binding mode to BuChE was different as the benzotriazole moiety is accommodated in the catalytic anionic site.publishedVersio
SÃntese de novos 1,2,3-triazóis derivados da bergenina, composições e uso como inibidores das enzimas glicosidases
DepositadaDescreve compostos triazólicos inibidores de alfa-glicosidades e seus processos de sÃntese. Os compostos da presente invenção compreendem o grupo 1,2-3-triazóis contendo a porção bergenina com atividade inibitória de α-glicosidases e seus derivados compreendendo certas fórmulas. Em outro aspecto da presente invenção, os compostos podem ser utilizados na obtenção de composições farmacêuticas com atividades antiproliferativa, antiobesidade, imunoestimulantes e antidiabetes
Uso das Pironofatoquinona como antiviral; composição farmacêutica contendo as Piranonaftoquinonas; medicamento contendo as Piranonaftoquinonas para tratamento de infecções causadas por virus da dengue
DepositadaDescreve o uso das Piranonaftoquinonas, assim como seus derivados, seus isômeros e seus sais como um agente antiviral, por inibir as enzimas ATPases viral. Além disso, também, faz parte desta invenção uma composição farmacêutica contendo as Piranonaftoquinonas descritas
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial
Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Development of tacrine clusters as positively cooperative systems for the inhibition of acetylcholinesterase
The synthesis of four tetra-tacrine clusters where the tacrine binding units are attached to a central scaffold via linkers of variable lengths is described. The multivalent inhibition potencies for the tacrine clusters were investigated for the inhibition of acetylcholinesterase. Two of the tacrine clusters displayed a small but significant multivalent inhibition potency in which the binding affinity of each of the tacrine binding units increased up to 3.2 times when they are connected to the central scaffold.publishedVersio
NQO1 induction mediated by photodynamic therapy synergizes with β-Lapachone-halogenated derivative against melanoma
The elevated expression of NQO1 in many human solid tumors along with its ability to activate quinone-based anticancer agents makes it an excellent target for enzyme-directed drug development. NQO1 plays an important role in melanogenesis and given its correlation with a poor patient outcome we propose this enzyme as an intriguing target for molecular-based therapeutic regimen against melanoma. Unfortunately, the natural product β-Lapachone (β-Lap), whose antitumor activity is based on NQO1, reported dose-limiting toxicity which hampered its pre-clinical and clinical use. Therefore, new effective and safe therapeutic NQO1-bioactivatable agents for melanoma treatment are desirable. Regarding NQO1, we demonstrated that halogenated β-Lap derivative named PFB is an excellent substrate and effective tumor-selective anticancer compound. In addition, PFB resulted more attractive than the parent β-Lap for treating metastatic-derived melanoma cells. In this context, it would be interesting to design strategies to induce NQO1 activity in cancer cells as a promising combinatorial approach with bioreductive drugs. In this sense, we had reported that photodynamic therapy (PDT) significantly upregulated NQO1 expression. Based on this event, here we demonstrated that the cytotoxic regimen consisting of PFB plus PDT improved synergistic therapeutic combination on melanoma cells. In conclusion, our contribution provides a strong rationale for using therapies that associate photo- and chemotherapy to effectively treat melanoma with modular NQO1 status.Fil: Lamberti, MarÃa Julia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de RÃo Cuarto. Facultad de Ciencias Exactas FisicoquÃmicas y Naturales; ArgentinaFil: Morales Vasconsuelo, Ana Belen. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de RÃo Cuarto. Facultad de Ciencias Exactas FisicoquÃmicas y Naturales; ArgentinaFil: Chiaramello, Marianela. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de RÃo Cuarto. Facultad de Ciencias Exactas FisicoquÃmicas y Naturales; ArgentinaFil: Ferreira, Vitor Francisco. Universidade Federal Fluminense; BrasilFil: Macedo Oliveira, Milena. Universidade Federal do Rio de Janeiro; BrasilFil: Baptista Ferreira, Sabrina. Universidade Federal do Rio de Janeiro; BrasilFil: Rivarola, Viviana Alicia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de RÃo Cuarto. Facultad de Ciencias Exactas FisicoquÃmicas y Naturales; ArgentinaFil: Rumie Vittar, Natalia Belen. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de RÃo Cuarto. Facultad de Ciencias Exactas FisicoquÃmicas y Naturales; Argentin