Signalling mechanisms that regulate metabolic profile and autophagy of acute myeloid leukaemia cells

Acute myeloid leukaemia (AML) comprises a heterogeneous group of hematologic neoplasms characterized by diverse combinations of genetic, phenotypic and clinical features representing a major challenge for the development of targeted therapies. Metabolic reprogramming, mainly driven by deregulation of the nutrient-sensing pathways as AMPK, mTOR and PI3K/AKT, has been associated with cancer cells, including AML cells, survival and proliferation. Nevertheless, the role of these metabolic adaptations on the AML pathogenesis is still controversial. In this work, the metabolic status and the respective metabolic networks operating in different AML cells (NB-4, HL-60 and KG-1) and their impact on autophagy and survival was characterized. Data show that whereas KG-1 cells exhibited preferential mitochondrial oxidative phosphorylation metabolism with constitutive co-activation of AMPK and mTORC1 associated with increased autophagy, NB-4 and HL-60 cells displayed a dependent glycolytic profile mainly associated with AKT/mTORC1 activation and low autophagy flux. Inhibition of AKT is disclosed as a promising therapeutical target in some scenarios while inhibition of AMPK and mTORC1 has no major impact on KG-1 cells' survival. The results highlight an exclusive metabolic profile for each tested AML cells and its impact on determination of the anti-leukaemia efficacy and on personalized combinatory therapy with conventional and targeted agents.This work was developed under the scope of the project NORTE‐01‐0145‐FEDER‐000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER), and by FEDER, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the project POCI‐01‐0145‐FEDER‐007038. OP and BSM are supported by fellowships from the Fundação para a Ciência e Tecnologia (FCT, Portugal) (SFRH/BD/52292/2013 and SFRH/BPD/90533/2012, respectively)info:eu-repo/semantics/publishedVersio

An integrated in vitro approach unveils the biocompetence and glutathiolomic profile of a human hepatocyte-like cell 3d model

Funding: This work was supported by FCT (Portugal) through the research grant PTDC/MED-TOX/29183/2017. Acknowledgments: The authors thank ECBio S.A. for providing the hnMSCs and F.A. Beland (NCTR, Jefferson, AR, USA) for the kind donation of nevirapine. FCT (UID/DTP/04138/2019, UID/QUI/00100/2019, RECI/QEQ-MED/0330/2012, SFRH/BD/144130/2019 to J.S.R., SFRH/BD/110945/2015 to P.F.P. and CEECIND/02001/2017 to A.M.M.A) are also acknowledged.The need for competent in vitro liver models for toxicological assessment persists. The differentiation of stem cells into hepatocyte-like cells (HLC) has been adopted due to its human origin and availability. Our aim was to study the usefulness of an in vitro 3D model of mesenchymal stem cell-derived HLCs. 3D spheroids (3D-HLC) or monolayer (2D-HLC) cultures of HLCs were treated with the hepatotoxic drug nevirapine (NVP) for 3 and 10 days followed by analyses of Phase I and II metabolites, biotransformation enzymes and drug transporters involved in NVP disposition. To ascertain the toxic effects of NVP and its major metabolites, the changes in the glutathione net flux were also investigated. Phase I enzymes were induced in both systems yielding all known correspondent NVP metabolites. However, 3D-HLCs showed higher biocompetence in producing Phase II NVP metabolites and upregulating Phase II enzymes and MRP7. Accordingly, NVP-exposure led to decreased glutathione availability and alterations in the intracellular dynamics disfavoring free reduced glutathione and glutathionylated protein pools. Overall, these results demonstrate the adequacy of the 3D-HLC model for studying the bioactivation/metabolism of NVP representing a further step to unveil toxicity mechanisms associated with glutathione net flux changes.publishersversionpublishe

El impacto de las expectativas sobre la adaptación académica de los estudiantes en la Educación Superior

Os desafios enfrentados pelos jovens, decorrentes do ingresso no Ensino Superior, têm sido alvo de inúmeras pesquisas, destacando a confluência de variáveis pessoais e contextuais nesse processo de transição e adaptação ao Ensino Superior. O presente estudo teve como objetivo investigar como as expectativas afetam a qualidade das vivências adaptativas dos acadêmicos que iniciam o Ensino Superior. Participaram deste estudo 182 estudantes brasileiros (M=26,2; DP=8,76), sendo 146 mulheres e 36 homens, que responderam a dois questionários reportados às expectativas e vivências acadêmicas. Os resultados indicaram que as expectativas iniciais dos ingressantes foram correlacionadas com a qualidade das suas vivências acadêmicas. Em particular, as expectativas de envolvimento nas relações com os colegas, no projeto vocacional de carreira e nas atividades curriculares do seu curso foram associadas à adaptação acadêmica dos estudantes.Many studies have addressed the challenges faced by students when they access higher education, describing the influence of personal and contextual factors on the transition and adaptation to Higher Education. The present study aimed to investigate how expectations impact the quality of first-year students’ experiences. Participants included 182 Brazilian students (M=26,2; DP=8,76), 146 women and 36 men, who answered two questionnaires focusing on academic expectations and experiences. Results suggest that initial expectations of first-year students are correlated with the quality of their academic experiences. Specifically, expectations about students’ engagement with colleagues, career project, and curricular activities in their undergraduate program, seem to be related with students’ academic adaptation.Los desafíos que enfrentan los jóvenes que resultan del ingreso a la educación superior han sido objeto de numerosas investigaciones, destacando la convergencia de variables personales y contextuales en este proceso de transición y adaptación a la educación superior. El presente estudio tuvo como objetivo investigar cómo las expectativas afectan la calidad de las experiencias de adaptación de los estudiantes que inician la educación superior. Participaron 182 estudiantes brasileños (M=26,2; DP=8,76), siendo 146 mujeres y 36 hombres, que respondieron dos cuestionarios direccionados a las expectativas y experiencias académicas. Los resultados indicaron que las expectativas iniciales de los estudiantes ingresantes se correlacionaron con la calidad de sus experiencias académicas. En particular, las expectativas de participación en las relaciones con los compañeros, en el proyecto de la carrera y en las actividades curriculares del curso fueron relacionadas con la adaptación académica de los estudiantes.Universidade do MinhoUniversidade Salgado de Oliveir

Demographic connectivity of sardine in the Bay of Biscay and Iberian coast region

Demographic connectivity in sardine populatio

Sucesso e insucesso no ensino básico : relevância de variáveis sócio-familiares e escolares em alunos do 5º ano

Tomando a globalidade dos alunos do 5º ano de uma EB2,3 da cidade de Braga, procedemos à caracterização destes alunos em termos de variáveis sócio-culturais, familiares e escolares. Particular destaque foi dado no estudo ao acompanhamento educativo e escolar que os alunos recebem no seio da família, assim como à forma como os alunos vivenciam a sua escola. Os resultados consideram os alunos diferenciados segundo o género e segundo o seu índice de aproveitamento escolar no final do ano lectivo. Em face da reduzida percentagem de alunos que não transitaram no final do ano lectivo, a opção foi por calcular a média das classificações nas várias disciplinas e, a partir dessa média, formar o grupo dos alunos com melhor e mais fraco rendimento. Algumas diferenças nos resultados, segundo o género e segundo o rendimento do aluno, são apresentadas e discutidas, mormente aquelas que poderão justificar alguma atenção por parte da escola e dos professores

NO-mediated apoptosis in yeast

Nitric oxide (NO) is a small molecule with distinct roles in diverse physiological functions in biological systems, among them the control of the apoptotic signalling cascade. By combining proteomic, genetic and biochemical approaches we demonstrate that NO and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) are crucial mediators of yeast apoptosis. Using indirect methodologies and a NO-selective electrode, we present results showing that H2O2-induced apoptotic cells synthesize NO that is associated to a nitric oxide synthase (NOS)-like activity as demonstrated by the use of a classical NOS kit assay. Additionally, our results show that yeast GAPDH is a target of extensive proteolysis upon H2O2-induced apoptosis and undergoes S-nitrosation. Blockage of NO synthesis with Nomega-nitro-L-arginine methyl ester leads to a decrease of GAPDH S-nitrosation and of intracellular reactive oxygen species (ROS) accumulation, increasing survival. These results indicate that NO signalling and GAPDH S-nitrosation are linked with H2O2-induced apoptotic cell death. Evidence is presented showing that NO and GAPDH S-nitrosation also mediate cell death during chronological life span pointing to a physiological role of NO in yeast apoptosis.This work was supported by a grant from FCT-Fundação para a Ciência e a Tecnologia (POCI/BIA-BCM/57364/2004). B.A. has a fellowship from FCT (SFRH/BD/15317/2005). We are also grateful to FWF for a Lipotox grant to F.M. and B.M. and for grant no. S-9304-B05 to F.M. and S.B

Reply to: Soils need to be considered when assessing the impacts of land-use change on carbon sequestration

Industrial Ecolog

A novel enzymatically-mediated drug delivery carrier for bone tissue engineering applications: combining biodegradable starch-based microparticles and differentiation agents

In many biomedical applications, the performance of biomaterials depends largely on their degradation behavior. For instance, in drug delivery applications, the polymeric carrier should degrade under physiological conditions slowly releasing the encapsulated drug. The aim of this work was, therefore, to develop an enzymaticmediated degradation carrier system for the delivery of differentiation agents to be used in bone tissue engineering applications. For that, a polymeric blend of starch with polycaprolactone (SPCL) was used to produce a microparticle carrier for the controlled release of dexamethasone (DEX). In order to investigate the effect of enzymes on the degradation behavior of the developed system and release profile of the encapsulated osteogenic agent (DEX), the microparticles were incubated in phosphate buffer solution in the presence of a-amylase and/or lipase enzymes (at physiological concentrations), at 37 C for different periods of time. The degradation was followed by gravimetric measurements, scanning electron microscopy (SEM) and Fourier transformed infrared (FTIR) spectroscopy and the release of DEX was monitored by high performance liquid chromatography (HPLC). The developed microparticles were shown to be susceptible to enzymatic degradation, as observed by an increase in weight loss and porosity with degradation time when compared with control samples (incubation in buffer only). For longer degradation times, the diameter of the microparticles decreased significantly and a highly porous matrix was obtained. The in vitro release studies showed a sustained release pattern with 48% of the encapsulated drug being released for a period of 30 days. As the degradation proceeds, it is expected that the remaining encapsulated drug will be completely released as a consequence of an increasingly permeable matrix and faster diffusion of the drug. Cytocompatibility results indicated the possibility of the developed microparticles to be used as biomaterial due to their reduced cytotoxic effects

HFE variants and the expression of iron-related proteins in breast cancer-associated lymphocytes and macrophages

Disponível em: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5264664/The association of HFE (High Iron FE) major variants with breast cancer risk and behavior has been a matter of discussion for a long time. However, their impact on the expression of iron-related proteins in the breast cancer tissue has never been addressed. In the present study, hepcidin, ferroportin 1, transferrin receptor 1 (TfR1), and ferritin expressions, as well as tissue iron deposition were evaluated in a collection of samples from breast cancers patients and analyzed according to the patients’ HFE genotype. Within the group of patients with invasive carcinoma, those carrying the p.Cys282Tyr variant in heterozygosity presented a higher expression of hepcidin in lymphocytes and macrophages than wild-type or p.His63Asp carriers. An increased expression of TfR1 was also observed in all the cell types analyzed but only in p.Cys282Tyr/p.His63Asp compound heterozygous patients. A differential impact of the two HFE variants was further noticed with the observation of a significantly higher percentage of p.Cys282Tyr heterozygous patients presenting tissue iron deposition in comparison to p.His63Asp heterozygous. In the present cohort, no significant associations were found between HFE variants and classical clinicopathological markers of breast cancer behavior and prognosis. Although limited by a low sampling size, our results provide a new possible explanation for the previously reported impact of HFE major variants on breast cancer progression, i.e., not by influencing systemic iron homeostasis but rather by differentially modulating the local cellular expression of iron-related proteins and tissue iron deposition.OM is a recipient of the PhD grant SFRH/BD/2011/78184 from Fundação para a Ciência e Tecnologia (FCT). The authors also acknowledge financial support from ICBAS/AI&NSUMIB and by national funds through FCT and Ministério da Educação e Ciência (MEC) and when applicable co-funded by FEDER funds within the partnership agreement PT2020 related with the research unit number 4293.info:eu-repo/semantics/publishedVersio

Meglumine antimoniate and miltefosine combined with allopurinol sustain pro-inflammatory immune environments during canine leishmaniosis treatment

Canine leishmaniosis (CanL) caused by Leishmania infantum is a zoonotic disease of global concern. Antileishmanial drug therapies commonly used to treat sick dogs improve their clinical condition, although when discontinued relapses can occur. Thus, the current study aims to evaluate the effect of CanL treatments in peripheral blood, lymph node, and bone marrow cytokine profile associated with clinical recovery. Two groups of six dogs diagnosed with CanL were treated with miltefosine combined with allopurinol and meglumine antimoniate combined with allopurinol (MT+A and MG+A), respectively. At diagnosis and after treatment, during a 3-month follow-up, clinical signs, hematological and biochemical parameters, urinalysis results and antileishmanial antibody titers were registered. Furthermore, peripheral blood, popliteal lymph node, and bone marrow samples were collected to assess the gene expression of IL-2, IL-4, IL-5, IL-10, IL-12, TNF-α, TGF-β, and IFN-γ by qPCR. In parallel, were also evaluated samples obtained from five healthy dogs. Both treatment protocols promoted the remission of clinical signs as well as normalization of hematological and biochemical parameters and urinalysis values. Antileishmanial antibodies returned to non-significant titers in all dogs. Sick dogs showed a generalized upregulation of IFN-γ and downregulation of IL-2, IL-4, and TGF-β, while gene expression of IL-12, TNF-α, IL-5, and IL-10 varied between groups and according to evaluated tissue. A trend to the normalization of cytokine gene expression was induced by both miltefosine and meglumine antimoniate combined therapies. However, IFN-γ gene expression was still up-regulated in the three evaluated tissues. Furthermore, the effect of treatment in the gene expression of cytokines that were not significantly changed by infection, indicates that miltefosine and meglumine antimoniate combined therapy directly affects cytokine generation. Both combined therapies are effective in CanL treatment, leading to sustained pro-inflammatory immune environments that can compromise parasite survival and favor dogs' clinical cure. In the current study, anti-inflammatory and regulatory cytokines do not seem to play a prominent role in CanL or during clinical recovery.publishersversionpublishe