Eggshell composition of Amazon turtle (Podocnemis expansa) is altered after incubation in substrates containing glyphosate and fipronil formulations.

Besides its crucial role during embryo development, eggshells are an essential bioindicator of environmental contaminants. However, the effects of contaminant exposure during incubation on the eggshell composition remain poorly known for freshwater turtles. Accordingly, we tested the effects of incubating the eggs of Podocnemis expansa in substrates containing glyphosate and fipronil formulations on the eggshell's level of mineral and dry matter, crude protein, nitrogen, and ethereal extract. Eggs were incubated in sand moistened with water contaminated with glyphosate Atar 48 at concentrations of 65 or 6500 µg/L, fipronil Regent 800 WG at concentrations of 4 or 400 µg/L, or the combination of 65 µg/L glyphosate and 4 µg/L fipronil and 6500 µg/L glyphosate with 400 µg/L fipronil. Exposure to the tested pesticides, alone or in association, altered the chemical composition of the eggshell of P. expansa, reducing the eggshell's moisture and crude protein content and increasing levels of ethereal extract. These changes may cause significant deficiencies in the mobilization of water and nutrients to the embryo, affecting the development and reproductive success of P. expansa.

Plastic microfibers as a risk factor for the health of aquatic organisms: A bibliometric and systematic review of plastic pandemic.

Plastic microfibers (PMFs) are emerging pollutants widely distributed in the environment. In the early 2020s, the need for personal protection due to the COVID-19 pandemic led to increased consumption of plastic materials (e.g., facemasks and gloves) and ultimately to increased plastic pollution, especially by PMFs. The PMFs present in the environment may be released in this form (primary particles) or in larger materials, that will release them as a result of environmental conditions. Although a considerable number of studies have been addressing the effects of microplastics, most of them studied round particles, with fewer studies focusing on PMFs. Thus, the current study aimed to summarize and critically discuss the available data concerning the ecotoxicological impact of PMFs on aquatic organisms. Aquatic organisms exposed to PMFs showed accumulation, mainly in the digestive tract, and several toxic effects, such as DNA damage, physiological alterations, digestive damage and even mortality, suggesting that PMFs can pose a risk for the health of aquatic organisms. The PMFs induced toxicity to aquatic invertebrate and vertebrate organisms depends on size, shape, chemical association and composition of fibers. Regarding other size range (nm) of plastic fibers, the literature review highlighted a knowledge gap in terms of the effects of plastic nanofibers on aquatic organisms. There is a knowledge gap in terms of the interaction and modes of action of PMFs associated with other pollutants. In addition, studies addressing effects at different trophic levels as well as the use of other biological models should be considered. Overall, research gaps and recommendations for future research and trends considering the environmental impact of the COVID-19 pandemic are presented.

Morphology of the brain base arteries of the giant anteater (Myrmecophaga tridactyla)

This study aimed to describe the brain base arteries of the Myrmecophaga tridactyla using ten cadavers of adults from this species, including five male and five female specimens. The arterial vascular bed was perfused via the thoracic aorta with a dyed natural latex solution, and the animals were fixed and preserved with a 10% formaldehyde buffered solution. The encephala were removed, and their vessels dissected. Basilar artery formation occurred by anastomosis of the thick ventral spinal artery with vertebral arteries. The basilar artery formed two arterial islands and gave bulbar and pontine branches, and cranial, middle, and caudal cerebellar arteries and ended by forking into its terminal branches, the caudal communicating arteries. The blood supply of the encephalon derived solely from the vertebrobasilar system, and the arterial circle of the brain was closed caudally and rostrally. The absence of participation of internal carotid arteries in encephalon irrigation, the island formations by the basilar artery, and the fusiform shape of the arterial circle of the brain are peculiar characteristics of the vascular anatomy of the brain base of M. tridactyla.

Acute exposure to environmentally relevant concentrations of benzophenone-3 induced genotoxicity in Poecilia reticulata.

The organic UV filter benzophenone-3 (BP-3), widely used in the commercial formulations of sunscreens and personal care products, is considered an emerging pollutant and has been associated with several human and environmental health concerns. However, knowledge about their mode of action and ecotoxicity on aquatic biota is scarce. In this scenario, the objective of this work was to evaluate the genotoxic, mutagenic, and erythrotoxicity effects of BP-3 in the guppy Poecilia reticulata after acute exposure. Adult females of P. reticulata were exposed to three non-lethal and environmentally relevant concentrations of BP-3 (10, 100, and 1000 ng L-1) during 96 h of exposure, and the somatic parameter [Fulton condition factor (K)], genotoxicity (comet assay), mutagenicity [micronucleus (MN) and erythrocyte nuclear abnormalities (ENA) tests] and erythrotoxicity parameters (such as total cell area and nucleus-cytoplasmic ratio) were analyzed. Results showed that the general physiological condition (K value) of fish was not affected by acute exposure to BP-3. However, BP-3 induced DNA damage at 100 and 1000 ng L-1 and increased the frequency of total ENA at 1000 ng L-1, specially lobed nucleus, when compared to control group, indicating its genotoxic and mutagenic effects. Furthermore, the BP-3 did not induce significant changes in the total cell area and nucleus-cytoplasmic ratio. In summary, results showed that the BP-3 at environmentally relevant concentration was genotoxic to freshwater fish P. reticulata, confirming its environmental risk.

Melanomacrophage response and hepatic histopathologic biomarkers in the guppy Poecilia reticulata exposed to iron oxide (maghemite) nanoparticles.

Although iron oxide nanoparticles (IONPs) have been widely used in nanomedicine and nanoremediation, their ecotoxicological effects on aquatic organisms remain unclear. In this study, the melanomacrophage center (MMC) response and hepatic histopathologic biomarkers were investigated in female guppies, Poecilia reticulata, exposed to citrate-functionalized IONPs (γ-Fe2O3) at an environmentally relevant iron concentration (0.3 mg L-1) over 21 days. The animals were collected at the beginning of the experiment and after 3, 7, 14, and 21 days of exposure. Guppies exposed to IONPs showed increases in the number, area, and perimeter of MMC when compared with the unexposed ones, especially after 7 days of exposure. The results showed an increase in the frequency of histopathologic changes in fish after 7 days of exposure to IONPs, such micro- and macro-vesicular steatosis, melanomacrophage aggregates, exudate, and hemorrhagic foci. The acute (3 and 7 days) and long-term (14 and 21 days) exposure of P. reticulata to IONPs induced high histopathologic indexes associated with circulatory disorders and inflammatory responses. Results showed that the MMC response and histopathologic index are important biomarkers to indicate the environmental impact of IONPs, confirming that the guppy P. reticulata is a target of ecotoxicity of IONPs.

Genotoxic and mutagenic assessment of iron oxide (maghemite-γ-Fe2O3) nanoparticle in the guppy Poecilia reticulata.

The environmental risk of nanomaterials (NMs) designed and used in nanoremediation process is of emerging concern, but their ecotoxic effects to aquatic organism remains unclear. In this study, the citrate-coated (maghemite) nanoparticles (IONPs) were synthesized and its genotoxic and mutagenic effects were investigated in the female guppy Poecilia reticulata. Fish were exposed to IONPs at environmentally relevant iron concentration (0.3 mg L-1) during 21 days and the animals were collected at the beginning of the experiment and after 3, 7, 14 and 21 days of exposure. The genotoxicity and mutagenicity were evaluated in terms of DNA damage (comet assay), micronucleus (MN) test and erythrocyte nuclear abnormalities (ENA) frequency. Results showed differential genotoxic and mutagenic effects of IONPs in the P. reticulata according to exposure time. The IONP induced DNA damage in P. reticulata after acute (3 and 7 days) and long-term exposure (14 and 21 days), while the mutagenic effects were observed only after long-term exposure. The DNA damage and the total ENA frequency increase linearly over the exposure time, indicating a higher induction rate of clastogenic and aneugenic effects in P. reticulata erythrocytes after long-term exposure to IONPs. Results indicated that the P. reticulata erythrocytes are target of ecotoxicity of IONPs.

Ação do licopeno nos músculos esquelético e cardíaco sob estresse oxidativo por exercícios / Action of lycopene on the cardiac and skeletal muscles under oxidative stress by exercises / Acción del licopeno en los músculos cardiaco y esquelético bajo estrés oxidativo por ejercicios

INTRODUÇÃO: Os radicais livres produzidos durante os exercícios podem exceder o sistema de defesa antioxidante, provocando danos oxidativos de biomoléculas específicas. As lesões causadas pelos radicais livres nas células podem ser prevenidas ou reduzidas por meio da atividade de antioxidantes naturais, sendo estes encontrados em muitos alimentos. O licopeno é um dos mais potentes carotenoides com ação antioxidante, sendo utilizado na prevenção da carcinogênese e aterogênese por proteger moléculas como lipídios, lipoproteínas de baixa densidade (LDL), proteínas e DNA. OBJETIVO: Investigar a atuação do licopeno a uma possível ação protetora das fibras musculares cardíacas e esqueléticas contra o estresse oxidativo, durante a atividade física exaustiva, a qual provocaria alterações morfológicas nesses tecidos. Método: Na realização dos experimentos foram utilizados 32 ratos machos adultos divididos em quatro grupos, sendo dois grupos controles e dois grupos treinados sem e com suplementação de licopeno (6 mg por animal). Os animais dos grupos treinados foram submetidos a 42 sessões de natação por nove semanas, com sessões diárias de natação, cinco dias por semana, com sobrecarga produzida pelo aumento do tempo de treinamento. A avaliação morfológica foi realizada por meio de lâminas histológicas dos tecidos cardíaco e muscular esquelético. RESULTADOS: Modificações teciduais cardíacas e musculares esqueléticas no grupo treinado sem suplementação com licopeno foram observadas, sendo que o grupo treinado suplementado apresentou aspecto morfológico normal. Nos grupos sedentários controle suplementado e não suplementado não houve alteração ...

INTRODUCTION: Free radicals produced during exercise may exceed the antioxidant defense system, causing oxidative damage to specific biomolecules. The lesions caused by free radicals in cells can be prevented or reduced by natural antioxidants, which are found in many foods. Lycopene is one of the most potent carotenoids with antioxidant properties, and it is used to prevent carcinogenesis and atherogenesis, as it protects molecules such as lipids, low-density lipoproteins (LDL), proteins and DNA. OBJECTIVE: To investigate the role of lycopene as a potential protector of cardiac and skeletal muscle fibers against oxidative stress during strenuous exercise, which would cause morphological changes in these tissues. METHODS: The experiments consisted of 32 adult male rats divided into four groups: two control groups and two trained groups with and without lycopene supplementation (6 mg per animal). The animals of the trained groups were subjected to 42 swimming sessions over a nine-week period, involving daily swimming sessions, five days a week, with overload produced by increasing the training time. The morphological analysis was performed using histological slides of cardiac and skeletal muscle tissues. RESULTS: Modifications were observed in cardiac and skeletal muscle tissue in the trained group that did not receive lycopene supplementation, while the trained group supplemented with lycopene showed muscle tissue with a normal morphological appearance. The tissues of both supplemented and non supplemented sedentary control groups showed no change in their histological characteristics. CONCLUSION: It can be stated that lycopene exerted a protective effect on cardiac and skeletal muscles against oxidative stress induced by strenuous exercise, besides promoting cardiac neovascularization, and can be used efficiently by athletes and physically active individuals. .

INTRODUCCIÓN: Los radicales libres producidos durante los ejercicios pueden exceder el sistema de defensa antioxidante, provocando daños oxidativos de biomoléculas específicas. Las lesiones causadas por los radicales libres en las células pueden ser prevenidas o reducidas por medio de la actividad de antioxidantes naturales, siendo éstos encontrados en muchos alimentos. El licopeno es uno de los más potentes carotenoides con acción antioxidante, siendo utilizado en la prevención de la carcinogénesis y aterogénesis por proteger moléculas como lípidos, lipoproteínas de baja densidad (LDL), proteínas y DNA. OBJETIVO: Investigar la actuación del licopeno a una posible acción protectora de las fibras musculares cardiacas y esqueléticas contra el estrés oxidativo, durante la actividad física exhaustiva, la cual provocaría alteraciones morfológicas en esos tejidos. MÉTODOS: En la realización de los experimentos fueron utilizados 32 ratones machos adultos divididos en cuatro grupos, siendo dos grupos controles y dos grupos entrenados sin y con suplementación de licopeno (6 mg por animal). Los animales de los grupos entrenados fueron sometidos a 42 sesiones de natación por nueve semanas, con sesiones diarias de natación, cinco días por semana, con sobrecarga producida por el aumento del tiempo de entrenamiento. La evaluación morfológica fue realizada por medio de láminas histológicas de los tejidos cardiaco y muscular esquelético. RESULTADOS: Fueron observadas modificaciones tisulares cardiacas y musculares esqueléticas en el grupo entrenado sin suplementación con licopeno, siendo que el grupo entrenado suplementado presentó aspecto morfológico normal. En los grupos sedentarios control suplementado y no suplementado no hubo alteración en relación ...