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1.
Ecotoxicology ; 31(8): 1189-1204, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36065034

RESUMO

Glyphosate herbicide is widely used in worldwide crop production. Consequently, its active ingredient, surfactants, and adjuvants commonly reach the aquatic ecosystem, thereby harming the biota. An investigation into how this herbicide affects aquatic species is important, especially in fish, as they have the ability to absorb and concentrate toxins. We aimed to evaluate the effects of glyphosate on the embryonic, larval and adult stages of zebrafish (Danio rerio), an appreciable organismal model. In this sense, we performed a meta-analysis using published articles from online databases (PubMed and ScienceDirect), which covered studies published until 2022. From a massive compilation of studies evaluating the effects of active substance glyphosate and Glyphosate-Based Herbicides (GBH) on zebrafish, we selected 36 studies used in downstream analyses. Overall, we report that glyphosate affects developmental stages and demonstrates toxicity and damage in zebrafish. We observed that embryos exposed to glyphosate exhibit increased mortality. There was also an increase in the number of morphological abnormalities related to yolk sac oedema, pericardial oedema, spinal curvature and body malformations, and a decrease in body size was observed. Furthermore, there was a decrease in the number of beats. The biochemical results demonstrated an increase in reactive oxygen species and antioxidant capacity against peroxyl radicals in the gills. The literature shows that glyphosate decreased the distance covered and the mean speed of the animals and increased the number of rotations. We concluded that glyphosate causes damage in the embryonic, larval and adult stages of this species. These results are valid for zebrafish and can be applied to other freshwater fish species. Graphical abstract.


Assuntos
Herbicidas , Peixe-Zebra , Animais , Antioxidantes , Ecossistema , Embrião não Mamífero , Glicina/análogos & derivados , Herbicidas/toxicidade , Larva , Espécies Reativas de Oxigênio , Tensoativos , Glifosato
2.
Mol Cell Biochem ; 407(1-2): 239-49, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26045174

RESUMO

Hot flashes, which involve a tiny rise in core temperature, are the most common complaint of peri- and post-menopausal women, being tightly related to decrease in estrogen levels. On the other hand, estradiol (E2) induces the expression of HSP72, a member of the 70 kDa family of heat shock proteins (HSP70), which are cytoprotective, cardioprotective, and heat inducible. Since HSP70 expression is compromised in age-related inflammatory diseases, we argued whether the capacity of triggering a robust heat shock (HS) response would be still present after E2 withdrawal. Hence, we studied the effects of HS treatment (hot tub) in female Wistar rats subjected to bilateral ovariectomy (OVX) after a 7-day washout period. Twelve h after HS, the animals were killed and aortic arches were surgically excised for molecular analyses. The results were compared with oxidative stress markers in the plasma (superoxide dismutase, catalase, and lipoperoxidation) because HSP70 expression is also sensitive to redox regulation. Extracellular (plasma) to intracellular HSP70 ratio, an index of systemic inflammatory status, was also investigated. The results showed that HS response was preserved in OVX animals, as inferred from HSP70 expression (up to 40% rise, p < 0.01) in the aortas, which was accompanied by no further alterations in oxidative stress, hematological parameters, and glycemic control either. This suggests that the lack of estrogen per se could not be solely ascribed as the unique source of low HSP70 expression as observed in long-term post-menopausal individuals. As a consequence, periodic evaluation of HSP70 status (iHSP70 vs. eHSP70) may be of clinical relevance because decreased HS response capacity is at the center of the onset of menopause-related dysfunctions.


Assuntos
Biomarcadores/metabolismo , Estrogênios/deficiência , Resposta ao Choque Térmico , Estresse Oxidativo , Animais , Aorta/metabolismo , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Temperatura Alta , Ovariectomia , Ratos
3.
Environ Sci Pollut Res Int ; 30(4): 9082-9102, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36441326

RESUMO

Glyphosate-based herbicides (GBHs) are the most worldwide used pesticides. The wide application of GBHs contaminates the soil and, consequently, water and food resources reaching human consumption. GBHs induce oxidative stress in non-target organisms, leading to a pro-inflammatory and pro-apoptotic cellular status, promoting tissue dysfunction and, thus, metabolic and neurobehavioral changes. This review presents evidence of oxidative damage induced by GBHs and the mechanism of cell damage and health consequences. To summarize, exposure to GBHs may induce disorders in calcium homeostasis related to the activation of ion channels. Also, alterations in pathways related to redox state regulation must have a primordial role in oxidative stress caused by GBHs.


Assuntos
Cálcio , Herbicidas , Humanos , Herbicidas/toxicidade , Estresse Oxidativo , Homeostase , Glifosato
4.
Neurotoxicol Teratol ; 95: 107147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36493994

RESUMO

Glyphosate-Based Herbicides (GBH) show risks to the environment and also to aquatic organisms, such as fish. The present work aimed to evaluate the effects of GBH and Pure Glyphosate (PG) exposure on Danio rerio embryos at drinking water concentrations. Zebrafish embryos were exposed to 250, 500, and 1000 µg L-1 of Roundup Original DI® and pure glyphosate for 96 h. Glyphosate concentration in water, parameters physicochemical water, survival, hatching rate, heart rate, malformations, behavior, and biomarkers were evaluated. We verified that at 6 h post-fertilization (hpf), animals exposed to GBH 500 showed decreased survival as compared to the control. The hatching rate increased in all groups exposed to GBH at 48 hpf as compared to the control group. The embryos exposed did not present changes in the spontaneous movement and touch response. Exposed groups to GBH demonstrated a higher number of malformations in fish embryos as compared to the control. Most malformations were: pericardial edema, yolk sac edema, body malformations, and curvature of the spine. In heart rate, bradycardia occurred in groups exposed, as predicted due to cardiac abnormalities. As biochemical endpoints, we observed a decrease in Glutathione S-transferase (GBH 250, GBH 500 and PG 250) and Acetylcholinesterase (GBH 250 and PG 250) activity. No differences were found between the groups in the concentration of protein, Total Antioxidant Capacity Against Peroxyl Radicals, Lipid peroxidation, Reactive Oxygen Species, Non-protein thiols, and Catalase. In conclusion, the damage in all evaluated stages of development was aggravated by survival and malformations. Therefore, the large-scale use of GBHs, coupled with the permissiveness of its presence could be the cause damage to the aquatic environment affecting the embryonic development of non-target organisms.


Assuntos
Herbicidas , Poluentes Químicos da Água , Animais , Larva , Peixe-Zebra , Herbicidas/toxicidade , Acetilcolinesterase/metabolismo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo , Glifosato
5.
Hum Reprod Update ; 23(5): 600-628, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28903474

RESUMO

BACKGROUND: Although some unequivocal underlying mechanisms of menopausal hot flushes have been demonstrated in animal models, the paucity of similar approaches in humans impedes further mechanistic outcomes. Human studies might show some as yet unexpected physiological mechanisms of metabolic adaptation that permeate the phase of decreased oestrogen levels in both symptomatic and asymptomatic women. This is particularly relevant because both the severity and time span of hot flushes are associated with increased risk of chronic inflammatory disease. On the other hand, oestrogen induces the expression of heat shock proteins of the 70 kDa family (HSP70), which are anti-inflammatory and cytoprotective protein chaperones, whose expression is modulated by different types of physiologically stressful situations, including heat stress and exercise. Therefore, lower HSP70 expression secondary to oestrogen deficiency increases cardiovascular risk and predisposes the patient to senescence-associated secretory phenotype (SASP) that culminates in chronic inflammatory diseases, such as obesities, type 2 diabetes, neuromuscular and neurodegenerative diseases. OBJECTIVE AND RATIONALE: This review focuses on HSP70 and its accompanying heat shock response (HSR), which is an anti-inflammatory and antisenescent pathway whose intracellular triggering is also oestrogen-dependent via nitric oxide (NO) production. The main goal of the manuscript was to show that the vasomotor symptoms that accompany hot flushes may be a disguised clue for important neuroendocrine alterations linking oestrogen deficiency to the anti-inflammatory HSR. SEARCH METHODS: Results from our own group and recent evidence on hypothalamic control of central temperature guided a search on PubMed and Google Scholar websites. OUTCOMES: Oestrogen elicits rapid production of the vasodilatory gas NO, a powerful activator of HSP70 expression. Whence, part of the protective effects of oestrogen over cardiovascular and neuroendocrine systems is tied to its capacity of inducing the NO-elicited HSR. The hypothalamic areas involved in thermoregulation (infundibular nucleus in humans and arcuate nucleus in other mammals) and whose neurons are known to have their function altered after long-term oestrogen ablation, particularly kisspeptin-neurokinin B-dynorphin neurons, (KNDy) are the same that drive neuroprotective expression of HSP70 and, in many cases, this response is via NO even in the absence of oestrogen. From thence, it is not illogical that hot flushes might be related to an evolutionary adaptation to re-equip the NO-HSP70 axis during the downfall of circulating oestrogen. WIDER IMPLICATIONS: Understanding of HSR could shed light on yet uncovered mechanisms of menopause-associated diseases as well as on possible manipulation of HSR in menopausal women through physiological, pharmacological, nutraceutical and prebiotic interventions. Moreover, decreased HSR indices (that can be clinically determined with ease) in perimenopause could be of prognostic value in predicting the moment and appropriateness of starting a HRT.


Assuntos
Resposta ao Choque Térmico , Fogachos/metabolismo , Menopausa/fisiologia , Óxido Nítrico/metabolismo , Animais , Estrogênios/fisiologia , Feminino , Proteínas de Choque Térmico/metabolismo , Humanos , Hipotálamo , Óxido Nítrico/sangue , Fatores de Risco
6.
Rev. bras. ativ. fís. saúde ; 27: 1-6, fev. 2022.
Artigo em Inglês | LILACS | ID: biblio-1418244

RESUMO

The appropriate area for walking, related to the flow of walking, on the sidewalks and crossing (walka-bility) influences the practice of physical activity. However, there is no evidence of meta-analyses that have evaluated this association. Therefore, this study presents a protocol to assess the association be-tween walkability and physical activity. The systematic review protocol was conducted following the PRISMA 2020 guidelines and will includes a search in the following databases: PubMed, SPORT-Discus, LILACS, Web of Science, Scopus, Embase, and Cochrane. It will include observational studies, cross-sectional and longitudinal, that assessed the association between walkability in the neighborhood and physical activity. The process of study selection will be conducted independently by two reviewers. The process will start by reading the titles and abstracts of interest, followed by the full reading of the articles through the Rayyan platform. We will assess the methodological and indi-vidual quality across the studies utilizing the Newcastle Ottawa Scale (NOS) and the Chi-Squared test (I2). To test the influence of variables in the meta-analysis results, we will use, whenever possible, the meta-regression technique. The meta-analysis results will be presented as Odds Ratio (OR) with 95% confidence interval, through a random or fixed-effects model, according to estimate of clinical, statistical, and methodological heterogeneity. If possible, stratifications will be performed according to age group, sex, and physical activity levels.With the expected results, we hope that the knowledge will be useful to encourage the implementation of public policies for walkability in the neighborhood to increase physical activity levels


A área adequada para caminhada, relacionada ao fluxo de caminhada, nas calçadas e travessias (walkability) influencia na prática de atividade física. No entanto, não há evidências de meta-análises que tenham avaliado essa associação. Portanto, este estudo apresenta um protocolo para avaliar a as-sociação entre walkability e atividade física. O protocolo de revisão sistemática será realizado seguin-do as recomendações do PRISMA 2020 e incluirá uma busca nas seguintes bases de dados: PubMed, SPORTDiscus, LILACS, Web of Science, Scopus, Embase e Cochrane. Serão incluídos estudos observacionais, transversais e longitudinais, que avaliaram a associação entre walkability na vizinhan-ça e atividade física. O processo de seleção dos estudos será conduzido de forma independente por dois revisores. O processo terá início pela leitura dos títulos e resumos de interesse, seguido da leitura completa dos artigos por meio da plataforma Rayyan. Avaliaremos a qualidade metodológica e in-dividual entre os estudos utilizando a Escala de Newcastle Ottawa (NOS) e o teste Qui-Quadrado (I2). Para testar a influência das variáveis nos resultados da meta-análise, utilizaremos, sempre que possível, a técnica de meta-regressão. Os resultados da meta-análise serão apresentados como Odds Ratio (OR) com intervalo de confiança de 95%, por meio de um modelo de efeitos aleatórios ou fixos, de acordo com a estimativa clínica, estatística e metodológica da heterogeneidade. Se possível, serão realizadas estratificações de acordo com faixa etária, sexo e níveis de atividade física. Com os resulta-dos do estudo, esperamos que o conhecimento seja útil para incentivar a implementação de políticas públicas de walkability no bairro para aumentar os níveis de atividade física


Assuntos
Exercício Físico , Metanálise em Rede , Revisão Sistemática , Estágios do Ciclo de Vida
7.
Movimento (Porto Alegre) ; 27: e27053, 2021.
Artigo em Português | LILACS | ID: biblio-1351130

RESUMO

Resumo O presente ensaio traz uma reflexão teórico-conceitual sobre as possibilidades de enfrentamentos realizados pela Educação Física Escolar nesse período de ensino remoto. Para isso, valoriza e ressignifica o lugar e o saber da experiência para o quem se ensina (sujeito da experiência), uma vez que este não pode ser universalizado, devido ao seu caráter de historicidade. A perda do lócus tradicional para a práxis pedagógica em Educação Física, substituído pelo espaço abstrato viável do aluno, nos desvela uma janela de renovação dos processos de ensino e aprendizagem em nosso campo de tematização. Concluímos que, para além do objeto, as intencionalidades pedagógicas e o conjunto "como, quando e onde ensinar" são questões indissociáveis que exigem o nosso protagonismo enquanto docentes da/na condição do ensino remoto. Disso é fundamental a compreensão de que não há possibilidade de substituição do tempo e espaço aula e que este é condição elementar da experiência.


Abstract This essay provides a theoretical and conceptual reflection on the potential confrontations faced by school Physical Education in this period of remote teaching. It considers and re-interprets the place of and knowledge about the experience taught (the subject of the experience) since this cannot be universalized due to its historicity character. The loss of the traditional locus for pedagogical praxis in Physical Education, replaced by the student's viable abstract space, reveals a window of renewal for teaching and learning processes in our thematic field. We conclude that, in addition to the object, pedagogical intentions and the whole - how, when, and where to teach - are inseparable issues that demand our action as teachers of/in the condition of remote education. It is essential to understand that it is not possible to replace time and class space, and that this is an elementary condition of the experience.


Resumen El presente ensayo trae una reflexión teórico-conceptual sobre las formas de enfrentamiento que realiza la Educación Física en la escuela en este período de educación remota. Para eso, valora y resignifica el lugar y el saber de la experiencia hacia quien es enseñado (sujeto de la experiencia), ya que éste no puede ser universalizado, debido a su carácter de historicidad. La pérdida del locus tradicional para la praxis pedagógica en Educación Física, sustituido por el espacio abstracto posible del alumno, nos revela una ventana de renovación de los procesos de enseñanza y aprendizaje en nuestro campo temático. Concluimos que, más allá del objeto, las intenciones pedagógicas y el conjunto: cómo, cuándo y dónde enseñar son cuestiones inseparables que exigen nuestro protagonismo como docentes de/en la condición de la enseñanza remota. Es fundamental entender que no hay posibilidad de una sustitución de tiempo y espacio clase, que es una condición elemental de la experiencia.


Assuntos
Humanos , Masculino , Feminino , Adaptação Psicológica , Educação a Distância , Pandemias , Aprendizagem
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