166 research outputs found
Study of the potential toxicity of adrenaline to neurons, using the SH-SY5Y human cellular model
Prolonged overexposure to catecholamines causes toxicity, usually credited to continuous adrenoceptor stimulation, autoxidation, and the formation of reactive pro-oxidant species. Non-differentiated SH-SY5Y cells were used to study the possible contribution of oxidative stress in adrenaline (ADR)-induced neurotoxicity, as a model to predict the toxicity of this catecholamine to peripheral nerves. Cells were exposed to several concentrations of ADR (0.1, 0.25, 0.5 and 1mM) and two cytotoxicity assays [lactate dehydrogenase (LDH) release and 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction] were performed at several time-points (24, 48, and 96h). The cytotoxicity of ADR was concentration- and time-dependent in both assays, since the lowest concentration tested (0.1mM) also caused significant cytotoxicity at 96h. N-acetyl-cysteine (1mM), a precursor of glutathione synthesis, prevented ADR-induced toxicity elicited by 0.5mM and 0.25mM ADR following a 96-h exposure, while the antioxidant Tiron (100µM) was non-protective. In conclusion, ADR led to mitochondrial distress and ultimately cell death in non-differentiated SH-SY5Y cells, possibly because of ADR oxidation products. The involvement of such processes in the catecholamine-induced peripheral neuropathy requires further analysis
Género masculino vs feminino: factor relevante para as respostas farmacológicas e efeitos adversos de fármacos?
As diferenças de eficácia dos fármacos, bem corno a sensibilidade para os seus efeitos adversos, entre o género masculino e o género feminino, constituem um tema de interesse actual e incontornável numa sociedade em que se pretende que as terapias individualizadas assumam uma importância crescente. No passado, as mulheres foram sub-representadas, ou mesmo excluídas, da participação em estudos clínicos durante o desenvolvimento de novos fármacos, assumindo-se que as diferenças entre o género feminino e masculino na farmacocinética e/ou farmacodinâmica desses novos fármacos não eram relevantes. Essa exclusão era igualmente justificada pela necessidade de uma amostragem muito superior que a inclusão de mulheres nos estudos implicaria. Actualmente, a noção de homogeneidade entre géneros tem vindo a mudar, pelo que as diferenças entre géneros têm vindo a ser consideradas relevantes e com implicações na eficácia e na segurança dos mais variados fármacos. Esta mudança de comportamento não será alheia ao facto de se ter verificado que o risco de reacções adversas a fármacos, no sexo feminino, pode atingir valores 1,5 a 1,7 vezes superiores quando comparado com o sexo masculino. Neste artigo é apresentada uma visão geral do estado actual do conhecimento sobre os mecanismos fisiológicos e moleculares responsáveis por esta variabilidade entre géneros e o impacto que tem relativamente a alguns medicamentos clinicamente relevantes e altamente consumidos em Portugal.
Adrenaline and Noradrenaline: Partners and Actors in the Same Play"
info:eu-repo/semantics/publishedVersio
A Metabolomics Study
Funding Information: This work is financed by national funds from Fundação para a Ciência e a Tecnologia (FCT), I.P., in the scope of the project UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences (UCIBIO) and the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB and through the project EXPL/MEDFAR/0203/2021. A. Dias-Carvalho acknowledges FCT and UCIBIO for her PhD grant (UI/BD/151318/2021). V.M.C acknowledges FCT for her grant (SFRH/BPD/110001/2015) that was funded by national funds through FCT under the Norma Transitória–DL57/2016/CP1334/CT0006. A.R.-M. acknowledges FCT for her grant SFRH/BD/129359/2017. Publisher Copyright: © 2023 by the authors.Long-term cognitive dysfunction, or “chemobrain”, has been observed in cancer patients treated with chemotherapy. Mitoxantrone (MTX) is a topoisomerase II inhibitor that binds and intercalates with DNA, being used in the treatment of several cancers and multiple sclerosis. Although MTX can induce chemobrain, its neurotoxic mechanisms are poorly studied. This work aimed to identify the adverse outcome pathways (AOPs) activated in the brain upon the use of a clinically relevant cumulative dose of MTX. Three-month-old male CD-1 mice were given a biweekly intraperitoneal administration of MTX over the course of three weeks until reaching a total cumulative dose of 6 mg/kg. Controls were given sterile saline in the same schedule. Two weeks after the last administration, the mice were euthanized and their brains removed. The left brain hemisphere was used for targeted profiling of the metabolism of glutathione and the right hemisphere for an untargeted metabolomics approach. The obtained results revealed that MTX treatment reduced the availability of cysteine (Cys), cysteinylglycine (CysGly), and reduced glutathione (GSH) suggesting that MTX disrupts glutathione metabolism. The untargeted approach revealed metabolic circuits of phosphatidylethanolamine, catecholamines, unsaturated fatty acids biosynthesis, and glycerolipids as relevant players in AOPs of MTX in our in vivo model. As far as we know, our study was the first to perform such a broad profiling study on pathways that could put patients given MTX at risk of cognitive deficits.publishersversionpublishe
Violence against Amazon women
Este é um estudo exploratório de natureza qualitativa, com o objetivo de analisar a violência contra mulheres amazônicas, apresentada na mídia impressa, segundo o tipo e sua gravidade, e citação de enquadramento do agressor na Lei Maria da Penha. Foram consultados 181 exemplares de um jornal regional. A partir da análise de conteúdo, foram selecionadas 164 notas sobre violências contra mulheres e incluídas, como corpus de análise, 46 delas. Os resultados foram reunidos em três grupos temáticos: mulheres assassinadas com crueldade, violência sexual contra mulheres não tem idade e violência contra mulheres e o limite da Lei Maria da Penha. A violência contra essas mulheres apresentou variação quanto à forma e à gravidade, ocorrendo inclusive homicídio. As mulheres são submetidas à violência sexual desde a infância até a idade adulta. O enquadramento legal do agressor demonstra à comunidade um meio para enfrentamento desse fenômeno social.Este es un estudio exploratorio de naturaleza cualitativa, que se realizó con el objetivo de analizar la violencia contra mujeres amazónicas, presentada en los periódicos, según el tipo y su gravedad, y citación de encuadramiento del agresor en la Ley Maria de la Penha. Fueron consultados 181 ejemplares de un periódico regional. A partir del análisis de contenido, fueron seleccionadas 164 notas sobre violencias contra mujeres, de ellas 46 fueron incluidas como corpus de análisis. Los resultados fueron reunidos en tres grupos temáticos: mujeres asesinadas con crueldad, la violencia sexual contra mujeres no tiene edad y la violencia contra mujeres y el límite de la Ley Maria de la Penha. La violencia contra esas mujeres presentó variación en cuanto a la forma y a la gravedad, ocurriendo inclusive homicidios. Las mujeres son sometidas a violencia sexual desde la infancia hasta la edad adulta. El encuadramiento legal del agresor demuestra a la comunidad un medio para enfrentamiento de ese fenómeno social.This quantitative and exploratory study analyzed violence against Amazon women presented in print media according to type and severity, and whether aggressors fell under the Maria da Penha law. A total of 181 issues of a regional newspaper were consulted. Based on content analysis, 164 items addressing violence against women were selected and 46 were included in the corpus of analysis. Results were gathered in three thematic groups: women killed with cruelty, sexual violence against women regardless of age, and violence against women and the limitations of the Maria da Penha law. Violence against these women varied in terms of form and severity, including up to homicide. Women are submitted to sexual violence from childhood through adulthood. The enforcement of this law shows the community it has a means to cope with this social phenomenon
Mitochondrial Cumulative Damage Induced by Mitoxantrone: Late Onset Cardiac Energetic Impairment
Mitoxantrone (MTX) is a chemotherapeutic
agent, which presents late irreversible cardiotoxicity. This
work aims to highlight the mechanisms involved in the
MTX-induced cardiotoxicity, namely the effects toward
mitochondria using in vivo and in vitro studies. Male
Wistar rats were treated with 3 cycles of 2.5 mg/kg MTX
at day 0, 10, and 20. One treated group was euthanized on
day 22 (MTX22) to evaluate the early MTX cardiac toxic
effects, while the other was euthanized on day 48
(MTX48), to allow the evaluation of MTX late cardiac
effects. Cardiac mitochondria isolated from 4 adult
untreated rats were also used to evaluate in vitro the MTX
(10 nM, 100 nM, and 1 lM) direct effects upon mitochondria
functionality. Two rats of MTX48 died on day 35,
and MTX treatment caused a reduction in relative body
weight gain in both treated groups with no significant
changes in water and food intake. Decreased levels of
plasma total creatine kinase and CK-MB were detected in
the MTX22 group, and increased plasma levels of lactate
were seen in MTX48. Increased cardiac relative mass and
microscopic changes were evident in both treated groups.
Considering mitochondrial effects, for the first time, it was
evidenced that MTX induced an increase in the complex IV
and complex V activities in MTX22 group, while a
decrease in the complex V activity was accompanied by the
reduction in ATP content in the MTX48 rats. No alterations
in mitochondria transmembrane potential were found in
isolated mitochondria from MTX48 rats or in isolated
mitochondria directly incubated with MTX. This study
highlights the relevance of the cumulative MTX-induced
in vivo mitochondriopathy to the MTX cardiotoxicity.This work was supported by the Fundação para
a Ciência e Tecnologia (FCT)—project (EXPL/DTP-FTO/0290/
2012)—QREN initiative with EU/FEDER financing through COMPETE—
Operational Programme for Competitiveness Factors. LGR,
VMC, and RJD-O thank FCT for their PhD Grant (SFRH/BD/63473/
2009) and Post-doc Grants (SFRH/BPD/63746/2009) and (SFRH/
BPD/36865/2007), respectively. The authors are grateful to Fundação
para a Ciência e Tecnologia for grant no. Pest C/EQB/LA0006/2011
Paracoccidoides brasiliensis 30 kDa adhesin: identification as a 14-3-3 protein, cloning and subcellular localization in infection models
Paracoccidoides brasiliensis adhesion to lung epithelial cells is considered an essential event for the establishment of infection and different proteins participate in this process. One of these proteins is a 30 kDa adhesin, pI 4.9 that was described as a laminin ligand in previous studies, and it was more highly expressed in more virulent P. brasiliensis isolates. This protein may contribute to the virulence of this important fungal pathogen. Using Edman degradation and mass spectrometry analysis, this 30 kDa adhesin was identified as a 14-3-3 protein. These proteins are a conserved group of small acidic proteins involved in a variety of processes in eukaryotic organisms. However, the exact function of these proteins in some processes remains unknown. Thus, the goal of the present study was to characterize the role of this protein during the interaction between the fungus and its host. To achieve this goal, we cloned, expressed the 14-3-3 protein in a heterologous system and determined its subcellular localization in in vitro and in vivo infection models. Immunocytochemical analysis revealed the ubiquitous distribution of this protein in the yeast form of P. brasiliensis, with some concentration in the cytoplasm. Additionally, this 14-3-3 protein was also present in P. brasiliensis cells at the sites of infection in C57BL/6 mice intratracheally infected with P. brasiliensis yeast cells for 72 h (acute infections) and 30 days (chronic infection). An apparent increase in the levels of the 14-3-3 protein in the cell wall of the fungus was also noted during the interaction between P. brasiliensis and A549 cells, suggesting that this protein may be involved in host-parasite interactions, since inhibition assays with the protein and this antibody decreased P. brasiliensis adhesion to A549 epithelial cells. Our data may lead to a better understanding of P. brasiliensis interactions with host tissues and paracoccidioidomycosis pathogenesis.FAPESP, 2011/18038-9National Council for Scientific and Technological Development, 473119/2010-2Coordenação de Aperfeiçoamento de Pessoal de Nível Superio
A breakthrough on Amanita phalloides poisoning: an effective antidotal effect by polymyxin B
Amanita phalloides is responsible for more than 90 % of mushroom-related fatalities, and no effective antidote is available. a-Amanitin, the main toxin of A. phalloides, inhibits RNA polymerase II (RNAP II), causing hepatic and kidney failure. In silico studies included docking and molecular dynamics simulation coupled to molecular mechanics with generalized Born and surface area method energy decomposition on RNAP II. They were performed with a clinical drug that shares chemical similarities to a-amanitin, polymyxin B. The results show that polymyxin B potentially binds to RNAP II in the same interface of a-amanitin, preventing the toxin from binding to RNAP II. In vivo, the inhibition of the mRNA transcripts elicited by a-amanitin was efficiently reverted by polymyxin B in the kidneys. Moreover, polymyxin B significantly decreased the hepatic and renal a-amanitin-induced injury as seen by the histology and hepatic aminotransferases plasma data. In the survival assay, all animals exposed to a-amanitin died within 5 days, whereas 50 % survived up to 30 days when polymyxin B was administered 4, 8, and 12 h post-a-amanitin. Moreover, a single dose of polymyxin B administered concomitantly with a-amanitin was able to guarantee 100 % survival. Polymyxin B protects RNAP II from inactivation leading to an effective prevention of organ damage and increasing survival in a-amanitin-treated animals. The present use of clinically relevant concentrations of an already human-use-approved drug prompts the use of polymyxin B as an antidote for A. phalloides poisoning in humans.Juliana Garcia, Vera Marisa Costa, Ricardo Dinis-Oliveira and Ricardo Silvestre thank FCT-Foundation for Science and Technology-for their PhD grant (SFRH/BD/74979/2010), Post-doc grants (SFRH/BPD/63746/2009 and SFRH/BPD/110001/2015) and Investigator grants (IF/01147/2013) and (IF/00021/2014), respectively. This work was supported by the Fundacao para a Ciencia e Tecnologia (FCT) - project PTDC/DTPFTO/4973/2014 - and the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundacao para a Ciencia e Tecnologia) through project Pest-C/EQB/LA0006/2013
Burden of Stroke in Europe:An Analysis of the Global Burden of Disease Study Findings From 2010 to 2019
BACKGROUND:While most European Regions perform well in global comparisons, large discrepancies within stroke epidemiological parameters exist across Europe. The objective of this analysis was to evaluate the stroke burden across European regions and countries in 2019 and its difference to 2010.METHODS:The GBD 2019 analytical tools were used to evaluate regional and country-specific estimates of incidence, prevalence, deaths, and disability-adjusted life years of stroke for the European Region as defined by the World Health Organization, with its 53 member countries (EU-53) and for European Union as defined in 2019, with its 28 member countries (EU-28), between 2010 and 2019. Results were analyzed at a regional, subregional, and country level.RESULTS:In EU-53, the absolute number of incident and prevalent strokes increased by 2% (uncertainty interval [UI], 0%–4%), from 1 767 280 to 1 802 559 new cases, and by 4% (UI, 3%–5%) between 2010 and 2019, respectively. In EU-28, the absolute number of prevalent strokes and stroke-related deaths increased by 4% (UI, 2%–5%) and by 6% (UI, 1%–10%), respectively. All-stroke age-standardized mortality rates, however, decreased by 18% (UI, −22% to −14%), from 82 to 67 per 100 000 people in the EU-53, and by 15% (UI, −18% to −11%), from 49.3 to 42.0 per 100 000 people in EU-28. Despite most countries presenting reductions in age-adjusted incidence, prevalence, mortality, and disability-adjusted life year rates, these rates remained 1.4×, 1.2×, 1.6×, and 1.7× higher in EU-53 in comparison to the EU-28.CONCLUSIONS:EU-53 showed a 2% increase in incident strokes, while they remained stable in EU-28. Age-standardized rates were consistently lower for all-stroke burden parameters in EU-28 in comparison to EU-53, and huge discrepancies in incidence, prevalence, mortality, and disability-adjusted life-year rates were observed between individual countries.<br/
- …