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The FLT3-ITD mutation represents the most frequent genetic alteration in newly diagnosed acute myeloid leukemia (AML) patient and is associated with poor prognosis. Mutation result in the retention of a constitutively active form of this receptor in the endoplasmic reticulum (ER) and the subsequent modification of its downstream effectors. Here, we assessed the impact of such retention on ER homeostasis and found that mutant cells present lower levels of ER stress due to the overexpression of ERO1α, one of the main proteins of the protein folding machinery at the ER. Overexpression of ERO1α resulted essential for ITD mutant cells survival and chemoresistance and also played a crucial role in shaping the type of glucose metabolism in AML cells, being the mitochondrial pathway the predominant one in those with a higher ER stress (non-mutated cells) and the glycolytic pathway the predominant one in those with lower ER stress (mutated cells). Our data indicate that FLT3 mutational status dictates the route for glucose metabolism in an ERO1α depending on manner and this provides a survival advantage to tumors carrying these ITD mutations.
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Estresse do Retículo Endoplasmático , Retículo Endoplasmático , Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo , Retículo Endoplasmático/metabolismo , Mutação , Linhagem Celular Tumoral , Glicoproteínas de Membrana , OxirredutasesRESUMO
Platinum(II) complexes bearing N-heterocyclic carbenes based guanosine and caffeine have been synthesized by unassisted C-H oxidative addition, leading to the corresponding trans-hydride complexes. Platinum guanosine derivatives bearing triflate as counterion or bromide instead of hydride as co-ligand were also synthesized to facilitate correlation between structure and activity. The hydride compounds show high antiproliferative activity against all cell lines (TC-71, MV-4-11, U-937 and A-172). Methyl Guanosine complex 3, bearing a hydride ligand, is up to 30â times more active than compound 4, with a bromide in the same position. Changing the counterion has no significant effect in antiproliferative activity. Increasing bulkiness at N7, with an isopropyl group (compound 6), allows to maintain the antiproliferative activity while decreasing toxicity for non-cancer cells. Compound 6 leads to an increase in endoplasmic reticulum and autophagy markers on TC71 and MV-4-11 cancer cells, induces reductive stress and increases glutathione levels in cancer cells but not in non-cancer cell line HEK-293.
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Antineoplásicos , Platina , Humanos , Platina/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Ligantes , Brometos , Células HEK293 , Guanosina , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos AntitumoraisRESUMO
Several oncogenic pathways plus local microenvironmental conditions, such as hypoxia, converge on the regulation of cancer cells metabolism. The major metabolic alteration consists of a shift from oxidative phosphorylation as the major glucose consumer to aerobic glycolysis, although most of cancer cells utilize both pathways to a greater or lesser extent. Aerobic glycolysis, together with the directly related metabolic pathways such as the tricarboxylic acid cycle, the pentose phosphate pathway, or gluconeogenesis are currently considered as therapeutic targets in cancer research. Melatonin has been reported to present numerous antitumor effects, which result in a reduced cell growth. This is achieved with both low and high concentrations with no relevant side effects. Indeed, high concentrations of this indolamine reduce proliferation of cancer types resistant to low concentrations and induce cell death in some types of tumors. Previous work suggest that regulation of glucose metabolism and other related pathways play an important role in the antitumoral effects of high concentration of melatonin. In the present review, we analyze recent work on the regulation by such concentrations of this indolamine on aerobic glycolysis, gluconeogenesis, the tricarboxylic acid cycle and the pentose phosphate pathways of cancer cells.
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Glucose/metabolismo , Melatonina/administração & dosagem , Neoplasias/metabolismo , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Proliferação de Células/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Glicólise/efeitos dos fármacos , HumanosRESUMO
Glioblastoma-initiating cells (GICs) represent a stem cell-like subpopulation within malignant glioblastomas responsible for tumor development, progression, therapeutic resistance, and tumor relapse. Thus, eradication of this subpopulation is essential to achieve stable, long-lasting remission. We have previously reported that melatonin decreases cell proliferation of glioblastoma cells both in vitro and in vivo and synergistically increases effectiveness of drugs in glioblastoma cells and also in GICs. In this study, we evaluated the effect of the indolamine alone in GICs and found that melatonin treatment reduces GICs proliferation and induces a decrease in self-renewal and clonogenic ability accompanied by a reduction in the expression of stem cell markers. Moreover, our results also indicate that melatonin treatment, by modulating stem cell properties, induces cell death with ultrastructural features of autophagy. Thus, data reported here reinforce the therapeutic potential of melatonin as a treatment of malignant glioblastoma both by inhibiting tumor bulk proliferation or killing GICs, and simultaneously enhancing the effect of chemotherapy.
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Autofagia/fisiologia , Neoplasias Encefálicas/patologia , Glioma/patologia , Melatonina/fisiologia , Sequência de Bases , Citometria de Fluxo , Humanos , Melatonina/farmacologia , Microscopia Eletrônica , Reação em Cadeia da Polimerase em Tempo RealRESUMO
INTRODUCTION: Patients with heart failure (HF) are known to have an increased risk of pulmonary embolism (PE), but there is limited evidence regarding the prognostic implications of HF in patients with acute PE and the relationship between PE prognosis and left ventricular ejection fraction (LVEF). The primary objective of this study was the development of a composite outcome (mortality, major bleeding, and recurrence) within the first 30 days. The secondary objective was to identify the role of LVEF in predicting the development of early complications in patients with both HF and reduced LVEF. MATERIAL AND METHODS: A prospective study was conducted at two tertiary hospitals between January 2012 and December 2022 to assess differences among patients diagnosed with acute PE based on the presence or absence of a history of HF. Cox regression models were employed to assess the impact of HF and reduced LVEF on the composite outcome at 30 days. RESULTS: Out of 1991 patients with acute symptomatic PE, 7.13% had a history of HF. Patients with HF were older and had more comorbidities. The HF group exhibited higher mortality (11.27% vs. 4.33%, p < 0.001) and a higher incidence of major bleeding (9.86% vs. 4.54%, p = 0.005). In the multivariate analysis, HF was an independent risk factor for the development of the composite outcome (HR 1.93; 95% CI 1.35-2.76). Reduced LVEF was independently associated with a higher risk of major bleeding (HR 3.44; 95% CI 1.34-8.81). CONCLUSION: In patients with acute pulmonary embolism, heart failure is independently associated with a higher risk of early complications. Additionally, heart failure with reduced LVEF is an independent risk factor for major bleeding.
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STAT3 is a pleiotropic transcription factor overactivated in 70% of solid tumours. We have recently reported that inactivating mutations on residues susceptible to post-translational modifications (PTMs) in only one of the monomers (i.e. asymmetric) caused changes in the cellular distribution of STAT3 homodimers. Here, we used more controlled experimental conditions, i.e. without the interference of endogenous STAT3 (STAT3-/- HeLa cells) and in the presence of a defined cytokine stimulus (Leukemia Inhibitory Factor, LIF), to provide further evidence that asymmetric PTMs affect the nuclear translocation of STAT3 homodimers. Time-lapse microscopy for 20 min after LIF stimulation showed that S727 dephosphorylation (S727A) and K685 inactivation (K685R) slightly enhanced the nuclear translocation of STAT3 homodimers, while K49 inactivation (K49R) delayed STAT3 nuclear translocation. Our findings suggest that asymmetrically modified STAT3 homodimers could be a new level of STAT3 regulation and, therefore, a potential target for cancer therapy.
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Núcleo Celular , Fator Inibidor de Leucemia , Multimerização Proteica , Processamento de Proteína Pós-Traducional , Fator de Transcrição STAT3 , Humanos , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Células HeLa , Fator Inibidor de Leucemia/metabolismo , Fosforilação , Transporte Proteico/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismoRESUMO
Coffee fruit cascara, which is the skin and pulp of the coffee cherry, has been authorized as a novel food for commercialization in the European Union. The present research assessed the feasibility of using spray drying to produce a soluble powder called instant cascara (IC), employing sun-dried ripe coffee cherry pulp as a raw material. Although there were no significant differences (p > 0.05) in the overall antioxidant capacity between the freeze-dried and spray-dried samples, after an in vitro simulation of the digestion process, the spray-dried sample was significantly (p < 0.05) more antioxidant. Both samples reduced physiological intracellular ROS and significantly decreased (p < 0.05) the secretion of the pro-inflammatory factor NO. Alkaloids and phenolic compounds were detected in intestinal digests. In conclusion, spray drying is a good technique for producing IC as its use does not affect its properties and causes less environmental impact than freeze drying, as calculated by life cycle assessment. Sensory analysis did not show significant differences between the commercial beverage and the IC beverage in the adult population. IC at 10 mg/mL was significantly less accepted in adolescents than the commercial beverage. Future work will include the reformulation of the IC beverage at 10 mg/mL, which has antioxidant and anti-inflammatory potential, to increase its hedonic acceptance in all consumer segments.
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Most children with medulloblastoma (MB) achieve remission, but some face very aggressive metastatic tumors. Their dismal outcome highlights the critical need to advance therapeutic approaches that benefit such high-risk patients. Minnelide, a clinically relevant analog of the natural product triptolide, has oncostatic activity in both preclinical and early clinical settings. Despite its efficacy and tolerable toxicity, this compound has not been evaluated in MB. Utilizing a bioinformatic data set that integrates cellular drug response data with gene expression, we predicted that Group 3 (G3) MB, which has a poor 5-year survival, would be sensitive to triptolide/Minnelide. We subsequently showed that both triptolide and Minnelide attenuate the viability of G3 MB cells ex vivo. Transcriptomic analyses identified MYC signaling, a pathologically relevant driver of G3 MB, as a downstream target of this class of drugs. We validated this MYC dependency in G3 MB cells and showed that triptolide exerts its efficacy by reducing both MYC transcription and MYC protein stability. Importantly, Minnelide acted on MYC to reduce tumor growth and leptomeningeal spread, which resulted in improved survival of G3 MB animal models. Moreover, Minnelide improved the efficacy of adjuvant chemotherapy, further highlighting its potential for the treatment of MYC-driven G3 MB.
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Diterpenos , Compostos de Epóxi , Meduloblastoma , Fenantrenos , Proteínas Proto-Oncogênicas c-myc , Ensaios Antitumorais Modelo de Xenoenxerto , Fenantrenos/farmacologia , Diterpenos/farmacologia , Compostos de Epóxi/farmacologia , Meduloblastoma/tratamento farmacológico , Meduloblastoma/genética , Meduloblastoma/patologia , Meduloblastoma/metabolismo , Animais , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Linhagem Celular Tumoral , Pró-Fármacos/farmacologia , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , OrganofosfatosRESUMO
It is well established that melatonin exerts antitumoral effects in many cancer types, mostly decreasing cell proliferation at low concentrations. On the other hand, induction of apoptosis by melatonin has been described in the last few years in some particular cancer types. The cytotoxic effect occurs after its administration at high concentrations, and the molecular pathways involved have been only partially determined. Moreover, a synergistic effect has been found in several cancer types when it is administered in combination with chemotherapeutic agents. In the present review, we will summarize published work on the pro-apoptotic effect of melatonin in cancer cells and the reported mechanisms involved in such action. We will also construct a hypothesis on how different cell signaling pathways may relate each other on account for such effect.
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Apoptose/efeitos dos fármacos , Melatonina/farmacologia , Neoplasias/patologia , Animais , Relação Dose-Resposta a Droga , Humanos , Modelos Biológicos , Neoplasias/metabolismo , Neoplasias/ultraestruturaRESUMO
The objectives of this study were (a) to describe and estimate the frequency of hemolytic uremic syndrome (HUS) in rural and urban populations in two regions of Buenos Aires Province, and (b) to compare the presentation and distribution of factors hypothetically associated with HUS. A total of 82 HUS cases, recorded during the years 2005-2010 in rural and urban areas of the south-central region of Buenos Aires Province, were clinically and epidemiologically characterized. Statistical data analysis included Chi square or Fisher test and median test. The incidence rate of HUS was significantly higher in the rural population, being 12.7 cases per 100 000 (CI 0-23.5) in rural inhabitants vs. 7.1 cases per 100 000 (CI 0-9.5) in urban inhabitants. The median age of the patients was 27 months (5-139 months), significantly lower in children from the rural area. This could be explained by a more frequent contact with bovine feces, the consumption of raw milk and a higher proportion of relatives who work in risk labors found in the rural population. Although HUS is often associated with the consumption of undercooked minced meat, most of the children cases here included did not present this antecedent. Clinical manifestations were similar in both subpopulations. One-third of urban patients had received antibiotics prior to HUS development.
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Infecções por Escherichia coli/complicações , Escherichia coli/isolamento & purificação , Síndrome Hemolítico-Urêmica/epidemiologia , Animais , Argentina/epidemiologia , Bovinos , Criança , Pré-Escolar , Escherichia coli O157/isolamento & purificação , Fezes/microbiologia , Feminino , Manipulação de Alimentos , Higiene das Mãos , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Higiene , Incidência , Lactente , Masculino , Leite/microbiologia , Estudos Retrospectivos , População Rural , Fatores Socioeconômicos , População UrbanaRESUMO
Most effective anticancer drugs normally generate considerable cytotoxicity in normal cells; therefore, the preferential activation of apoptosis in cancer cells and the reduction of toxicity in normal cells is a great challenge in cancer research. Natural products with selective anticancer properties used as complementary medicine can help to achieve this goal. The aim of the present study was to analyze the effect of the addition of bee products [propolis (PR) or royal jelly (RJ) or propolis and royal jelly (PR+RJ), 2-10%] to thyme (TH) and chestnut honeys (CH) on the differential anticancer properties, mainly the cytotoxic and pro-apoptotic effects, in normal and cancer hepatic cells. The cytotoxic effects of samples were analyzed using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay (0-250 mg/mL) and the effects on apoptosis were analyzed using cell cycle analysis, TdT-dUTP terminal nick-end labeling (TUNEL) assay, DR5 (Death Receptor 5) and BAX (BCL-2-Associated X) activation, and caspases 8, 9, and 3 activities. Both honey samples alone and honey mixtures had no or very little apoptotic effect on normal cells. Antioxidant honey mixtures enhanced the apoptotic capacity of the corresponding honey alone via both extrinsic and intrinsic pathways. Of all the samples, chestnut honey enriched with 10% royal jelly and 10% propolis (sample 14, CH+10RJ+10PR) showed the highest apoptotic effect on tumor liver cells. The enrichment of monofloral honey with bee products could be used together with conventional anticancer treatments as a dietary supplement without side effects. On the other hand, it could be included in the diet as a natural sweetener with high added value.
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OBJECTIVES: To describe the management of superficial vein thrombosis (SVT) of the lower limbs in patients treated in Spanish hospital emergency departments (EDs). To evaluate the impact of ED management of venous thromboembolic complications on outcomes and to determine the characteristics of patients who develop complications. MATERIAL AND METHODS: The retrospective multicenter ALTAMIRA study (Spanish acronym for risk factors, complications, and assessment of Spanish ED management of SVT) used recorded data for consecutive patients with a diagnosis of isolated SVT treated in 18 EDs. We gathered data on symptomatic venous thromboembolic disease (deep vein thrombosis, pulmonary embolism, or the extension or recurrence of SVT), clinically significant bleeding, and 180-day mortality. Cox regression analysis was used to explore variables associated with complications. RESULTS: A total of 703 patients were included. Anticoagulation was prescribed for 84.1% of the patients for a median of 30 days (interquartile range, 15-42 days); 81.3% were treated with low molecular weight heparin. A prophylactic dose was prescribed for 48% and an intermediate therapeutic dose for 52%. Sixty-four patients (9.2%) developed symptomatic thromboembolic disease within 180 days, 12 (1.7%) experienced clinically significant bleeding, and 4 (0.6%) died. Complications developed later in patients receiving anticoagulant therapy than in those not taking an anticoagulant (66 vs 11 days , P=.009), and 76.6% of those developing complications were not on anticoagulant when symptoms appeared. A history of thromboembolic disease was associated with developing complications (adjusted hazard ratio, 2.20; 95% confidence interval, 1.34-3.62). CONCLUSION: ED treatment of SVT varies and is often suboptimal. The incidence of thromboembolic complications after SVT is high. Starting anticoagulation in the ED delays the development of complications. Patients with a history of thromboembolic disease are more at risk of complications.
OBJETIVO: Describir el manejo terapéutico de los pacientes con trombosis venosa superficial (TVS) aislada de miembros inferiores en servicios de urgencias hospitalarios (SUH) españoles. Evaluar el impacto del tratamiento instaurado en urgencias en la evolución, en términos de complicaciones de enfermedad tromboembólica venosa (ETV), y conocer las características de los pacientes que sufren complicaciones. METODO: El estudio multicentrico (18 SUH) ALTAMIRA (fActores de riesgo, compLicaciones y evaluación del manejo de la TVS de Miembros Inferiores en hospitales españoles atendidos en los seRvicios de urgenciAs) creó un cohorte retrospectivo de pacientes consecutivos con diagnóstico objetivo de TVS aislada. Se recogieron las complicaciones de ETV sintomáticas (trombosis venosa profunda, tromboembolia pulmonar y extensión o recurrencia de TVS), sangrados clínicamente relevantes y defunciones a 180 días. Se evaluaron las variables asociadas a las complicaciones mediante una regresión de Cox. RESULTADOS: Se incluyeron 703 pacientes. El 84,1% recibieron anticoagulación durante 30 días (rango intercuartil 15-42), 81,3% con heparina de bajo peso molecular (48% dosis profilácticas, 52% intermedias-terapéuticas). En 180 días, 64 pacientes (9,1%) tuvieron complicación de ETV, 12 (1,7%) tuvieron sangrado clínicamente relevante, y 4 fallecieron (0,6%). Los pacientes en que se instauró anticoagulación en urgencias tardaron más tiempo en desarrollar complicaciones (66 vs 11 días, p = 0,009). El 76,6% de los que se complicaron no estaban anticoagulados en ese momento. La ETV previa se asoció de forma independiente con el desarrollo de complicaciones (hazard ratio ajustada 2,20; intervalo de confianza del 95%: 1,34-3,62). CONCLUSIONES: El tratamiento en urgencias de la TVS aislada es heterogéneo y con frecuencia subóptimo. La incidencia de complicaciones de ETV es elevada. El tratamiento anticoagulante iniciado en urgencias supone un retraso en el desarrollo de complicaciones. Los pacientes con ETV previa tienen más riesgo de complicaciones.
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Embolia Pulmonar , Trombose Venosa , Humanos , Trombose Venosa/tratamento farmacológico , Trombose Venosa/etiologia , Trombose Venosa/diagnóstico , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/etiologia , Extremidade Inferior/irrigação sanguínea , Anticoagulantes , Heparina de Baixo Peso Molecular/uso terapêutico , Hemorragia/induzido quimicamenteRESUMO
BACKGROUND: Pilot clinical trials have shown the safety of intra-arterial bone marrow mononuclear cells (BMMNCs) in stroke. However, the efficacy of different doses of intra-arterial BMMNCs in patients with acute stroke has not been tested in a randomised clinical trial. We aimed to show safety and efficacy of two different doses of autologous intra-arterial BMMNC transplantation in patients with acute stroke. METHODS: The IBIS trial was a multicentre phase 2, randomised, controlled, investigator-initiated, assessor-blinded, clinical trial, in four stroke centres in Spain. We included patients (aged 18-80 years) with a non-lacunar, middle cerebral artery ischaemic stroke within 1-7 days from stroke onset and with a National Institutes of Health Stroke Scale score of 6-20. We randomly assigned patients (2:1:1) with a computer-generated randomisation sequence to standard of care (control group) or intra-arterial injection of autologous BMMNCs at one of two different doses (2â×â106 BMMNCs/kg or 5â×â106 BMMNCs/kg). The primary efficacy outcome was the proportion of patients with modified Rankin Scale scores of 0-2 at 180 days in the intention-to-treat population, comparing each BMMNC dose group and the pooled BMMNC group versus the control group. The primary safety endpoint was the proportion of serious adverse events. This trial was registered at ClinicalTrials.gov, NCT02178657 and is completed. FINDINGS: Between April 1, 2015, and May 20, 2021, we assessed 114 patients for eligibility. We randomly assigned 77 (68%) patients: 38 (49%) to the control group, 20 (26%) to the low-dose BMMNC group, and 19 (25%) the high-dose BMMNC group. The mean age of participants was 62·4 years (SD 12·7), 46 (60%) were men, 31 (40%) were women, all were White, and 63 (82%) received thrombectomy. The median NIHSS score before randomisation was 12 (IQR 9-15), with intra-arterial BMMNC injection done a median of 6 days (4-7) after stroke onset. The primary efficacy outcome occurred in 14 (39%) patients in the control group versus ten (50%) in the low-dose group (adjusted odds ratio 2·08 [95% CI 0·55-7·85]; p=0·28), eight (44%) in the high-dose group (1·89 [0·52-6·96]; p=0·33), and 18 (47%) in the pooled BMMNC group (2·22 [0·72-6·85]; p=0·16). We found no differences in the proportion of patients who had adverse events or dose-related events, but two patients had a groin haematoma after cell injection in the low-dose BMMNC group. INTERPRETATION: Intra-arterial BMMNCs were safe in patients with acute ischaemic stroke, but we found no significant improvement at 180 days on the mRS. Further clinical trials are warranted to investigate whether improvements might be possible at different timepoints. FUNDING: Instituto de Salud Carlos III co-funded by the European Regional Development Fund/European Social Fund, Mutua Madrileña, and the Regional Ministry of Health of Andalusia.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Espanha , Medula Óssea , Resultado do Tratamento , Transplante de CélulasRESUMO
Parkinson's disease has been widely related to both apoptosis and oxidative stress. Many publications relate the loss of mitochondrial potential to an apoptosis-mediated cell death in different in vivo and in vitro models of this pathology. The present study used the dopaminegic specific neurotoxin 1-methyl-4-phenylpyridinium (MPP(+) ) on neuron-like PC12 cells, which is a well-accepted model of Parkinson's disease. Results showed an early increase in oxidants, which drives the modulation of c-Jun N-terminal kinase (JNK) and AKT/mammalian target of rapamycin (mTOR) pathways, mimicking peroxide treatment. However, the cell death found in neuronal PC12 cells treated with MPP(+) was not a caspase-associated apoptosis. Electron microscopic images illustrated autophagic cell death, which was confirmed by a Beclin-1 and ATG expression increase, accumulation of acidic vesicles, and rescue by an autophagy inhibitor. In conclusion, the boost in oxidants from MPP(+) treatment in neuronal PC12 is modulating both survival (AKT/mTOR) and death (JNK) pathways, which are the perpetrators of an autophagic cell death.
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Autofagia/fisiologia , MAP Quinase Quinase 4/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Western Blotting , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Estresse Oxidativo/fisiologia , Células PC12 , Ratos , Transdução de Sinais/fisiologiaRESUMO
PURPOSE: Chondrosarcoma and osteosarcoma are the most frequently occurring bone cancers. Although surgery and chemotherapy are currently clinically applied, improved treatment options are urgently needed. Melatonin is known to inhibit cell proliferation in both tumor types. Although the underlying mechanisms are not clear yet, calcium homeostasis has been reported to be a key factor in cancer biology. Here, we set out to investigate whether regulation of calcium by this indolamine may be involved in its antitumor effect. METHODS: Cell viability was measured using a MTT assay and flow cytometry was used to measure levels of cytosolic calcium, intracellular oxidants, mitochondrial membrane potential and cell cycle progression. Mitochondrial calcium was analyzed by fluorimetry. Cell migration was determined using a scratch wound-healing assay. Western blot analysis was used to assess the expression of proteins related to cell cycle progression, epithelial to mesenchymal transition (EMT), Ac-CoA synthesis and intracellular signaling pathways. RESULTS: We found that melatonin decreases cytosolic and mitochondrial Ca2+ levels, intracellular oxidant levels, mitochondrial function and the expression of the E1 subunit of the pyruvate dehydrogenase complex. These changes were found to be accompanied by decreases in cell proliferation, cell migration and EMT marker expression. The addition of CaCl2 prevented the changes mentioned above, while co-treatment with the calcium chelator BAPTA enhanced the effects. CONCLUSIONS: Our data indicate that regulation of calcium homeostasis is a key factor in the inhibition of cell proliferation and migration by melatonin. This effect should be taken into consideration in combined therapies with traditional or new antitumor compounds, since it may circumvent therapy resistance.
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Neoplasias Ósseas , Melatonina , Osteossarcoma , Neoplasias de Tecidos Moles , Neoplasias Ósseas/patologia , Cálcio/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Humanos , Melatonina/farmacologia , Melatonina/uso terapêutico , Osteossarcoma/patologiaRESUMO
Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a neurodegenerative disorder commonly diagnosed in infants and characterized by progressive cerebellar ataxia, spasticity, motor sensory neuropathy and axonal demyelination. ARSACS is caused by mutations in the SACS gene that lead to truncated or defective forms of the 520 kDa multidomain protein, sacsin. Sacsin function is exclusively studied on neuronal cells, where it regulates mitochondrial network organization and facilitates the normal polymerization of neuronal intermediate filaments (i.e., neurofilaments and vimentin). Here, we show that sacsin is also highly expressed in astrocytes, C6 rat glioma cells and N9 mouse microglia. Sacsin knockout in C6 cells (C6Sacs-/-) induced the accumulation of the glial intermediate filaments glial fibrillary acidic protein (GFAP), nestin and vimentin in the juxtanuclear area, and a concomitant depletion of mitochondria. C6Sacs-/- cells showed impaired responses to oxidative challenges (Rotenone) and inflammatory stimuli (Interleukin-6). GFAP aggregation is also associated with other neurodegenerative conditions diagnosed in infants, such as Alexander disease or Giant Axonal Neuropathy. Our results, and the similarities between these disorders, reinforce the possible connection between ARSACS and intermediate filament-associated diseases and point to a potential role of glia in ARSACS pathology.
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Deleção de Genes , Filamentos Intermediários/metabolismo , Chaperonas Moleculares/metabolismo , Neuroglia/metabolismo , Animais , Animais Recém-Nascidos , Linhagem Celular Tumoral , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Rotenona/toxicidadeRESUMO
OBJECTIVES: A bronchiolitis integrated care pathway (BICP) proved useful in reducing the use of unnecessary medications at a local level. The aim of this study was to reduce overtreatment by scaling up the BICP across our regional health service in the 2019 and 2020 bronchiolitis season. METHODS: We conducted a quality improvement (QI) initiative in 115 primary care (PC) centers and 7 hospitals in the Basque Country, Spain, from October 2019 to March 2020. The primary outcome measure was the percentage of children prescribed salbutamol comparing the rate to that in the previous bronchiolitis season (October 2018-March 2019). Secondary outcomes were the use of other medications. Balancing measures were hospitalization and unscheduled return rates. RESULTS: We included 8153 PC visits, 3424 emergency department (ED) attendances, and 663 inpatient care episodes, of which 3817 (46.8%), 1614 (47.1%), and 328 (49.4%) occurred in the postintervention period, respectively. Salbutamol use decreased from 27.1% to 4.7%, 29.5% to 3.0%, and 44.4% to 3.9% (P < .001) in PC centers, Eds, and hospital wards, respectively. In PC, corticosteroid and antibiotic prescribing rates fell from 10.1% to 1.7% and 13.7% to 5.1%, respectively (P < .001). In EDs and hospital wards, epinephrine use rates fell from 14.2% to 4.2% (P < .001) and 30.4% to 19.8% (P = .001), respectively. No variations were noted in balancing measures. CONCLUSIONS: The scaling up of the BICP was associated with significant decreases in the use of medications in managing bronchiolitis across a regional health service without unintended consequences.
Assuntos
Bronquiolite , Criança , Humanos , Lactente , Espanha , Bronquiolite/tratamento farmacológico , Serviço Hospitalar de Emergência , Albuterol/uso terapêutico , Melhoria de QualidadeRESUMO
Establishing the relationship between gut microbiota and host health has become a main target of research in the last decade. Human gut microbiota-associated animal models represent one alternative to human research, allowing for intervention studies to investigate causality. Recent cohort and in vitro studies proposed an altered gut microbiota and lactate metabolism with excessive H2 production as the main causes of infant colic. To evaluate H2 production by infant gut microbiota and to test modulation of gut colonizer lactose- and lactate-utilizer non-H2-producer, Cutibacterium avidum P279, we established and validated a gnotobiotic model using young germ-free rats inoculated with fecal slurries from infants younger than 3 months. Here, we show that infant microbiota-associated (IMA) rats inoculated with fresh feces from healthy (n = 2) and colic infants (n = 2) and fed infant formula acquired and maintained similar quantitative and qualitative fecal microbiota composition compared to the individual donor's profile. We observed that IMA rats excreted high levels of H2, which were linked to a high abundance of lactate-utilizer H2-producer Veillonella. Supplementation of C. avidum P279 to colic IMA rats reduced H2 levels compared to animals receiving a placebo. Taken together, we report high H2 production by infant gut microbiota, which might be a contributing factor for infant colic, and suggest the potential of C. avidum P279 in reducing the abdominal H2 production, bloating, and pain associated with excessive crying in colic infants.
RESUMO
The aim of the present study was to validate the cytotoxicity, genotoxicity, and preventive potential against benzo(a)pyrene (BaP)-induced DNA damage of nine samples of thyme and chestnut honeys enriched with bee products (royal jelly and propolis, 2-10%). Cell viability was determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay (0-250 mg/mL) to select nontoxic concentrations, and DNA damage (0.1-10 µg/mL) was evaluated by the alkaline single-cell gel electrophoresis or comet assay. Treatment with honey samples or royal jelly and propolis did not affect the viability of HepG2 cells up to 100 and 50 mg/mL, respectively. Treatment with 100 µM BaP significantly increased (p ≤ 0.001) the levels of the DNA strand breaks. None of the tested concentrations (0.1-10 µg/mL) of the honey samples (thyme and chestnut), royal jelly, and propolis caused DNA damage per se. All tested samples at all the concentrations used decreased the genotoxic effect of BaP. In addition, all mixtures of thyme or chestnut honeys with royal jelly or propolis showed a greater protective effect against BaP than the samples alone, being the thyme and chestnut honey samples enriched with 10% royal jelly and 10% propolis the most effective (70.4% and 69.4%, respectively). The observed protective effect may be associated with the phenolic content and antioxidant capacity of the studied samples. In conclusion, the thyme and chestnut honey samples enriched with bee products present potential as natural chemoprotective agents against the chemical carcinogen BaP.
Assuntos
Mel , Própole , Thymus (Planta) , Mel/análise , Benzo(a)pireno/toxicidade , Própole/farmacologia , Dano ao DNARESUMO
SRY (sex determining region Y)-box 2 (SOX2)-labeled cells play key roles in chemoresistance and tumor relapse; thus, it is critical to elucidate the mechanisms propagating them. Single-cell transcriptomic analyses of the most common malignant pediatric brain tumor, medulloblastoma (MB), revealed the existence of astrocytic Sox2+ cells expressing sonic hedgehog (SHH) signaling biomarkers. Treatment with vismodegib, an SHH inhibitor that acts on Smoothened (Smo), led to increases in astrocyte-like Sox2+ cells. Using SOX2-enriched MB cultures, we observed that SOX2+ cells required SHH signaling to propagate, and unlike in the proliferative tumor bulk, the SHH pathway was activated in these cells downstream of Smo in an MYC-dependent manner. Functionally different GLI inhibitors depleted vismodegib-resistant SOX2+ cells from MB tissues, reduced their ability to further engraft in vivo, and increased symptom-free survival. Our results emphasize the promise of therapies targeting GLI to deplete SOX2+ cells and provide stable tumor remission.