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

MECANISMOS MOLECULARES SUBJACENTES AO CATABOLISMO MUSCULAR PROMOVIDO PELA DOXORRUBICINA

Chemotherapeutic agents like doxorubicin (DOX) are the foundation for the treatment of a variety of malignancies; however, these therapies have several side-effects. DOX may trigger or potentiate the muscle wasting observed in cancer patients, which is particularly worrying in frail old patients. Therefore, it is important to comprehend the mechanisms responsible for DOX-induced toxicity in skeletal muscle, to identify therapeutic targets envisioning the improvement of survival rates and quality of life of these patients. Hence, this review discusses the molecular players that may be involved in DOX-induced muscle wasting. From the analysis performed herein, DOX seems to induce the activation of the proteolytic ubiquitin proteasome pathway (UPP), which in turn can also be enhanced by DOX-induced increase in myostatin and tumor necrosis factor (TNF)-α signaling pathways, as well as insulin resistance. Furthermore, DOX-induced oxidative stress and mitochondrial dysfunction may also be critical contributors for muscle wasting. All these mechanisms may contribute to the loss of skeletal muscle mass and function observed after DOX exposure, which may lead to or aggravate cachexia, responsible for more than 20% of all cancer-related deaths.Os fármacos utilizados na quimioterapia como a doxorrubicina (DOX) são essenciais para o tratamento de vários tipos de cancro. No entanto, esta terapia tem vários efeitos secundários associados. A DOX pode potenciar a perda de massa muscular observada em pacientes com cancro, o que é particularmente preocupante em pacientes idosos. Assim, é necessário compreender os mecanismos responsáveis pela toxidade da DOX no músculo esquelético, de forma a identificar alvos terapêuticos e a aumentar as taxas de sobrevivência e qualidade de vida destes pacientes. Esta revisão discute os mediadores moleculares que poderão estar envolvidos na perda de massa muscular induzida pela DOX. Da análise realizada, a DOX parece promover a ativação da via da ubiquitina-proteassoma, ativação essa que pode ser intensificada pela elevação, induzida pela DOX, da atividade das vias da miostatina e do fator de necrose tumoral alfa, bem como pela presença de resistência à insulina. A DOX parece também induzir stress oxidativo e disfunção mitocondrial, o que poderá contribuir para a perda da massa muscular. Todos estes mecanismos parecem ser cruciais para impulsionar a perda de massa e de função muscular observadas após a exposição à DOX, o que poderá resultar ou agravar a caquexia, que é responsável por mais do que 20% de todas as mortes relacionadas com o cancro

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

Cardiac molecular remodeling by anticancer drugs: Doxorubicin affects more metabolism while mitoxantrone impacts more autophagy in adult CD-1 male mice

Doxorubicin (DOX) and mitoxantrone (MTX) are classical chemotherapeutic agents used in cancer that induce similar clinical cardiotoxic effects, although it is not clear if they share similar underlying molecular mechanisms. We aimed to assess the effects of DOX and MTX on the cardiac remodeling, focusing mainly on metabolism and autophagy. Adult male CD-1 mice received pharmacologically relevant cumulative doses of DOX (18 mg/kg) and MTX (6 mg/kg). Both DOX and MTX disturbed cardiac metabolism, decreasing glycolysis, and increasing the dependency on fatty acids (FA) oxidation, namely, through decreased AMP-activated protein kinase (AMPK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) content and decreased free carnitine (C0) and increased acetylcarnitine (C2) concentration. Additionally, DOX heavily influenced glycolysis, oxidative metabolism, and amino acids turnover by exclusively decreasing phosphofructokinase (PFKM) and electron transfer flavoprotein-ubiquinone oxidoreductase (ETFDH) content, and the concentration of several amino acids. Conversely, both drugs downregulated autophagy given by the decreased content of autophagy protein 5 (ATG5) and microtubule-associated protein light chain 3 (LC3B), with MTX having also an impact on Beclin1. These results emphasize that DOX and MTX modulate cardiac remodeling differently, despite their clinical similarities, which is of paramount importance for future treatments.info:eu-repo/semantics/publishedVersio

Natural Sympathomimetic Drugs: From Pharmacology to Toxicology

Sympathomimetic agents are a group of chemical compounds that are able to activate the sympathetic nervous system either directly via adrenergic receptors or indirectly by increasing endogenous catecholamine levels or mimicking their intracellular signaling pathways. Compounds from this group, both used therapeutically or abused, comprise endogenous catecholamines (such as adrenaline and noradrenaline), synthetic amines (e.g., isoproterenol and dobutamine), trace amines (e.g., tyramine, tryptamine, histamine and octopamine), illicit drugs (e.g., ephedrine, cathinone, and cocaine), or even caffeine and synephrine. In addition to the effects triggered by stimulation of the sympathetic system, the discovery of trace amine associated receptors (TAARs) in humans brought new insights about their sympathomimetic pharmacology and toxicology. Although synthetic sympathomimetic agents are mostly seen as toxic, natural sympathomimetic agents are considered more complacently in the terms of safety in the vision of the lay public. Here, we aim to discuss the pharmacological and mainly toxicological aspects related to sympathomimetic natural agents, in particular of trace amines, compounds derived from plants like ephedra and khat, and finally cocaine. The main purpose of this review is to give a scientific and updated view of those agents and serve as a reminder on the safety issues of natural sympathomimetic agents most used in the community

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

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

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