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1.
Mitochondrion ; 77: 101901, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38777222

RESUMO

Zebrafish are a powerful tool to study a myriad of experimental conditions, including mitochondrial bioenergetics. Considering that mitochondria are different in many aspects depending on the tissue evaluated, in the zebrafish model there is still a lack of this investigation. Especially for juvenile zebrafish. In the present study, we examined whether different tissues from zebrafish juveniles show mitochondrial density- and tissue-specificity comparing brain, liver, heart, and skeletal muscle (SM). The liver and brain complex IV showed the highest O2 consumption of all ETC in all tissues (10x when compared to other respiratory complexes). The liver showed a higher potential for ROS generation. In this way, the brain and liver showed more susceptibility to O2- generation when compared to other tissues. Regarding Ca2+ transport, the brain showed greater capacity for Ca2+ uptake and the liver presented low Ca2+ uptake capacity. The liver and brain were more susceptible to producing NO. The enzymes SOD and Catalase showed high activity in the brain, whereas GPx showed higher activity in the liver and CS in the SM. TEM reveals, as expected, a physiological diverse mitochondrial morphology. The essential differences between zebrafish tissues investigated probably reflect how the mitochondria play a diverse role in systemic homeostasis. This feature may not be limited to normal metabolic functions but also to stress conditions. In summary, mitochondrial bioenergetics in zebrafish juvenile permeabilized tissues showed a tissue-specificity and a useful tool to investigate conditions of redox system imbalance, mainly in the liver and brain.


Assuntos
Metabolismo Energético , Mitocôndrias , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cálcio/metabolismo , Encéfalo/metabolismo , Especificidade de Órgãos , Fígado/metabolismo , Consumo de Oxigênio , Músculo Esquelético/metabolismo
2.
Ecotoxicol Environ Saf ; 275: 116254, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38547729

RESUMO

Heavy metal exposure leads to multiple system dysfunctions. The mechanisms are likely multifactorial and involve inflammation and oxidative stress. The aim of this study was to evaluate markers and risk factors for atherosclerosis in the LDL receptor knockout mouse model chronically exposed to inorganic mercury (Hg) in the drinking water. Results revealed that Hg exposed mice present increased plasma levels of cholesterol, without alterations in glucose. As a major source and target of oxidants, we evaluated mitochondrial function. We found that liver mitochondria from Hg treated mice show worse respiratory control, lower oxidative phosphorylation efficiency and increased H2O2 release. In addition, Hg induced mitochondrial membrane permeability transition. Erythrocytes from Hg treated mice showed a 50% reduction in their ability to take up oxygen, lower levels of reduced glutathione (GSH) and of antioxidant enzymes (SOD, catalase and GPx). The Hg treatment disturbed immune system cells counting and function. While lymphocytes were reduced, monocytes, eosinophils and neutrophils were increased. Peritoneal macrophages from Hg treated mice showed increased phagocytic activity. Hg exposed mice tissues present metal impregnation and parenchymal architecture alterations. In agreement, increased systemic markers of liver and kidney dysfunction were observed. Plasma, liver and kidney oxidative damage indicators (MDA and carbonyl) were increased while GSH and thiol groups were diminished by Hg exposure. Importantly, atherosclerotic lesion size in the aorta root of Hg exposed mice were larger than in controls. In conclusion, in vivo chronic exposure to Hg worsens the hypercholesterolemia, impairs mitochondrial bioenergetics and redox function, alters immune cells profile and function, causes several tissues oxidative damage and accelerates atherosclerosis development.


Assuntos
Aterosclerose , Hipercolesterolemia , Mercúrio , Animais , Camundongos , Aterosclerose/induzido quimicamente , Peróxido de Hidrogênio , Nefropatias , Mercúrio/toxicidade , Camundongos Knockout , Estresse Oxidativo/fisiologia , Receptores de LDL/genética
3.
Foods ; 13(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38397554

RESUMO

Electric field-based technologies offer interesting perspectives which include controlled heat dissipation (via the ohmic heating effect) and the influence of electrical variables (e.g., electroporation). These factors collectively provide an opportunity to modify the functional and technological properties of numerous food proteins, including ones from emergent plant- and microbial-based sources. Currently, numerous scientific studies are underway, contributing to the emerging body of knowledge about the effects on protein properties. In this review, "Electric Field Processing" acknowledges the broader range of technologies that fall under the umbrella of using the direct passage of electrical current in food material, giving particular focus to the ones that are industrially implemented. The structural and biological effects of electric field processing (thermal and non-thermal) on protein fractions from various sources will be addressed. For a more comprehensive contextualization of the significance of these effects, both conventional and alternative protein sources, along with their respective ingredients, will be introduced initially.

4.
Food Microbiol ; 113: 104251, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37098418

RESUMO

The viability of SARS-CoV-2 on food surfaces and its propagation through the food chain has been discussed by several stakeholders, as it may represent a serious public health problem, bringing new challenges to the food system. This work shows for the first time that edible films can be used against SARS-CoV-2. Sodium alginate-based films containing gallic acid, geraniol, and green tea extract were evaluated in terms of their antiviral activity against SARS-CoV-2. The results showed that all these films have strong in vitro antiviral activity against this virus. However, a higher concentration of the active compound (1.25%) is needed for the film containing gallic acid to achieve similar results to those obtained for lower concentrations of geraniol and green tea extract (0.313%). Furthermore, critical concentrations of the active compounds in the films were used to evaluate their stability during storage. Results showed that gallic acid-loaded films lose their activity from the second week of storage, while films with geraniol and green tea extract only show a drop in activity after four weeks. These results highlight the possibility of using edible films and coatings as antiviral materials on food surfaces or food contact materials, which may help to reduce the spreading of viruses through the food chain.


Assuntos
COVID-19 , Filmes Comestíveis , Humanos , Alginatos , Embalagem de Alimentos/métodos , SARS-CoV-2 , Antioxidantes , Extratos Vegetais/farmacologia , Chá , Antivirais/farmacologia , Ácido Gálico/farmacologia
5.
J Trace Elem Med Biol ; 71: 126928, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35032836

RESUMO

BACKGROUND: Thimerosal (TM) is an organic mercury compound used as a preservative in many pharmacological inputs. Mercury toxicity is related to structural and functional changes in macromolecules such as hemoglobin (Hb) in erythrocytes (Ery). METHOD: Human Hb and Ery were used to evaluate O2 uptake based on the TM concentration, incubation time, and temperature. The influence of TM on the sulfhydryl content, production of reactive oxygen species (ROS), and membrane fragility was also evaluated. Raman spectra and atomic force microscopy (AFM) profiles for Ery in the presence and absence of TM were calculated, and docking studies were performed. RESULTS: At 37 °C, with 2.50 µM TM (higher concentration) and after 5 min of incubation in Hb and Ery, we observed a reduction in O2 uptake of up to 50 %, while HgCl2, which was used as a positive control, showed a reduction of at least 62 %. Total thiol assays in the presence of NEM (thiol blocker) quantified the preservation of almost 60 % of free SH in Ery. Based on the Raman spectrum profile from Ery-TM, structural differences in the porphyrinic ring and the membrane lipid content were confirmed. Finally, studies using AFM showed changes in the morphology and biomechanical properties of Ery. Theoretical studies confirmed these experimental results and showed that the cysteine (Cys) residues present in Hb are involved in the binding of TM. CONCLUSION: Our results show that TM binds to human Hb via free Cys residues, causing conformation changes and leading to harmful effects associated with O2 transport.


Assuntos
Compostos de Mercúrio , Mercúrio , Humanos , Timerosal/farmacologia , Timerosal/metabolismo , Eritrócitos/metabolismo , Cisteína , Hemoglobinas , Compostos de Sulfidrila/metabolismo
6.
FASEB J ; 35(7): e21685, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34085343

RESUMO

Leucine zipper-EF-hand containing transmembrane protein 1 (Letm1) is a mitochondrial inner membrane protein involved in Ca2+ and K+ homeostasis in mammalian cells. Here, we demonstrate that the Letm1 orthologue of Trypanosoma cruzi, the etiologic agent of Chagas disease, is important for mitochondrial Ca2+ uptake and release. The results show that both mitochondrial Ca2+ influx and efflux are reduced in TcLetm1 knockdown (TcLetm1-KD) cells and increased in TcLetm1 overexpressing cells, without alterations in the mitochondrial membrane potential. Remarkably, TcLetm1 knockdown or overexpression increases or does not affect mitochondrial Ca2+ levels in epimastigotes, respectively. TcLetm1-KD epimastigotes have reduced growth, and both overexpression and knockdown of TcLetm1 cause a defect in metacyclogenesis. TcLetm1-KD also affected mitochondrial bioenergetics. Invasion of host cells by TcLetm1-KD trypomastigotes and their intracellular replication is greatly impaired. Taken together, our findings indicate that TcLetm1 is important for Ca2+ homeostasis and cell viability in T cruzi.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Doença de Chagas/parasitologia , Mitocôndrias/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/crescimento & desenvolvimento , Animais , Transporte Biológico , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/genética , Chlorocebus aethiops , Metabolismo Energético , Potencial da Membrana Mitocondrial , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/genética , Trypanosoma cruzi/metabolismo , Células Vero
7.
Ecotoxicol Environ Saf ; 219: 112337, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34029837

RESUMO

Mercury in the aquatic environment can lead to exposure of the human population and is a known toxic metal due to its capacity for accumulation in organs. We aimed to evaluate the mercury level in the blood and urine of fishermen and correlate it with the level of oxidative stress in blood cells. We show in this case-control study that the fishermen of the exposed group (case) of Mundaú Lagoon (Maceió - Alagoas, Brazil) have higher concentrations of total mercury in the blood (0.73-48.38 µg L-1) and urine (0.430-10.2 µg L-1) than the total mercury concentrations in blood (0.29-17.30 µg L-1) and urine (0.210-2.65 µg L-1) of the control group. In the blood cells of fishermen, we observed that the lymphomononuclear cells produced high levels of reactive oxygen species (61.7%), and the erythrocytes presented increased lipid peroxidation (151%) and protein oxidation (41.0%) and a decrease in total thiol (36.5%), GSH and the REDOX state (16.5%). The activity of antioxidant system enzymes (SOD, GPx, and GST) was also reduced in the exposed group by 26.9%, 28.3%, and 19.0%, respectively. Furthermore, hemoglobin oxygen uptake was decreased in the exposed group (40.0%), and the membrane of cells presented increased osmotic fragility (154%) compared to those in the control group. These results suggest that mercury in the blood of fishermen can be responsible for causing impairments in the oxidative status of blood cells and is probably the cause of the reduction in oxygen uptake capacity and damage to the membranes of erythrocytes.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Mercúrio/toxicidade , Estresse Oxidativo/fisiologia , Animais , Antioxidantes/metabolismo , Células Sanguíneas/metabolismo , Brasil , Estudos de Casos e Controles , Exposição Ambiental/análise , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Humanos , Peroxidação de Lipídeos , Mercúrio/análise , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
8.
Mol Neurobiol ; 58(3): 1217-1236, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33123979

RESUMO

Status epilepticus (SE) is defined as continuous and self-sustaining seizures, which trigger hippocampal neurodegeneration, mitochondrial dysfunction, oxidative stress, and energy failure. During SE, the neurons become overexcited, increasing energy consumption. Glucose uptake is increased via the sodium glucose cotransporter 1 (SGLT1) in the hippocampus under epileptic conditions. In addition, modulation of glucose can prevent neuronal damage caused by SE. Here, we evaluated the effect of increased glucose availability in behavior of limbic seizures, memory dysfunction, neurodegeneration process, neuronal activity, and SGLT1 expression. Vehicle (VEH, saline 0.9%, 1 µL) or glucose (GLU; 1, 2 or 3 mM, 1 µL) were administered into hippocampus of male Wistar rats (Rattus norvegicus) before or after pilocarpine to induce SE. Behavioral analysis of seizures was performed for 90 min during SE. The memory and learning processes were analyzed by the inhibitory avoidance test. After 24 h of SE, neurodegeneration process, neuronal activity, and SGLT1 expression were evaluated in hippocampal and extrahippocampal regions. Modulation of hippocampal glucose did not protect memory dysfunction followed by SE. Our results showed that the administration of glucose after pilocarpine reduced the severity of seizures, as well as the number of limbic seizures. Similarly, glucose after SE reduced cell death and neuronal activity in hippocampus, subiculum, thalamus, amygdala, and cortical areas. Finally, glucose infusion elevated the SGLT1 expression in hippocampus. Taken together our data suggest that possibly the administration of intrahippocampal glucose protects brain in the earlier stage of epileptogenic processes via an important support of SGLT1.


Assuntos
Glucose/metabolismo , Hipocampo/metabolismo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Morte Celular , Hipocampo/enzimologia , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Consolidação da Memória , Neurônios/patologia , Estresse Oxidativo , Pilocarpina , Ratos Wistar , Índice de Gravidade de Doença , Transportador 1 de Glucose-Sódio/metabolismo , Estado Epiléptico/fisiopatologia
9.
Sci Adv ; 6(17)2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32917582

RESUMO

Observations of the redshift z = 7.085 quasar J1120+0641 are used to search for variations of the fine structure constant, α, over the redshift range 5.5 to 7.1. Observations at z = 7.1 probe the physics of the universe at only 0.8 billion years old. These are the most distant direct measurements of α to date and the first measurements using a near-IR spectrograph. A new AI analysis method is employed. Four measurements from the x-shooter spectrograph on the Very Large Telescope (VLT) constrain changes in a relative to the terrestrial value (α0). The weighted mean electromagnetic force in this location in the universe deviates from the terrestrial value by Δα/α = (α z - α0)/α0 = (-2.18 ± 7.27) × 10-5, consistent with no temporal change. Combining these measurements with existing data, we find a spatial variation is preferred over a no-variation model at the 3.9σ level.

10.
Int J Biol Macromol ; 154: 661-671, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32198046

RESUMO

Thimerosal (TH), an organomercurial compound, is used as a preservative in vaccines and cosmetics. Its interaction with human hemoglobin (Hb) was investigated under physiological conditions using biophysical and biological assays, aiming to evaluate hazardous effects. TH interacts spontaneously with Hb (stoichiometry 2:1, ligand-protein), preferably by electrostatic forces, with a binding constant of 1.41 × 106 M-1. Spectroscopic data allows to proposing that TH induces structural changes in Hg, through ethylmercury transfer to human Hb-Cys93 residues, forming thiosalicylic acid, which, in turn, interacts with the positive side of the amino acid in the Hb-HgEt adduct chain. As a consequence, inhibition of Hb-O2 binding capacity up to 72% (human Hb), and 50% (human erythrocytes), was verified. Dose-dependent induction of TH forming advanced glycation end products (AGE) and protein aggregates (amyloids) was additionally observed. Finally, these results highlight the toxic potential of the use of TH in biological systems, with a consequent risk to human health.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Conservantes Farmacêuticos/toxicidade , Timerosal/toxicidade , Humanos
11.
Toxicology ; 413: 24-32, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30528861

RESUMO

Gold nanorods (AuNRs) have been studied extensively in biomedicine due to their biocompatibility and their unique properties. Some studies reported that AuNRs selectively accumulate on cancer cell mitochondria causing its death. However, the immediate effects of this accumulation needed further investigations. In this context, we evaluated the effect of AuNRs on the mitochondrial integrity of isolated rat liver mitochondria. We verified that AuNRs decreased the mitochondrial respiratory ratio by decreasing the phosphorylation and maximal states. Additionally, AuNRs caused a decrease in the production of mitochondrial ROS and a delay in mitochondrial swelling. Moreover, even with cyclosporine A treatment, AuNRs disrupted the mitochondrial potential. With the highest concentration of AuNRs studied, disorganized mitochondrial crests and intermembrane separation were observed in TEM images. These results indicate that AuNRs can interact with mitochondria, disrupting the electron transport chain. This study provides new evidence of the immediate effects of AuNRs on mitochondrial bioenergetics.


Assuntos
Ouro/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Nanotubos/toxicidade , Consumo de Oxigênio/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Ouro/metabolismo , Masculino , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar
12.
Exp Gerontol ; 109: 47-50, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28213051

RESUMO

Ageing and atherosclerosis are associated with oxidative stress. Mitochondrial redox function declines with ageing. Here we tested whether ageing LDL receptor knockout mice (LDLr-/-) develop spontaneous atherosclerosis and whether mitochondrial reactive oxygen species (mtROS) correlate with atherosclerosis. Compared with young mice, aged LDLr-/- mice exhibited 20-fold larger aortic lesion size, although the plasma cholesterol levels did not vary between age groups. The lesion sizes increased exponentially from 3 to 24months of age (r=0.92, p=0.0001) and were correlated with mtROS across the age range (r=0.81, p=0.0001). Thus, LDLr-/- mice develop spontaneous diet-independent atherosclerosis, that advances exponentially with ageing. We propose that age related increases in mtROS contribute to accelerate atherosclerosis development in hypercholesterolemic mice.


Assuntos
Envelhecimento , Aterosclerose/etiologia , Hipercolesterolemia/complicações , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Masculino , Camundongos , Camundongos Knockout , Receptores de LDL/fisiologia
13.
Appl Physiol Nutr Metab ; 39(8): 880-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24905448

RESUMO

Protein restriction during perinatal and early postnatal development is associated with a greater incidence of disease in the adult, such arterial hypertension. The aim in the present study was to investigate the effect of maternal low-protein diet on mitochondrial oxidative phosphorylation capacity, mitochondrial reactive oxygen species (ROS) formation, antioxidant levels (enzymatic and nonenzymatic), and oxidative stress levels on the heart of the adult offspring. Pregnant Wistar rats received either 17% casein (normal protein, NP) or 8% casein (low protein, LP) throughout pregnancy and lactation. After weaning male progeny of these NP or LP fed rats, females were maintained on commercial chow (Labina-Purina). At 100 days post-birth, the male rats were sacrificed and heart tissue was harvested and stored at -80 °C. Our results show that restricting protein consumption in pregnant females induced decreased mitochondrial oxidative phosphorylation capacity (51% reduction in ADP-stimulated oxygen consumption and 49.5% reduction in respiratory control ratio) in their progeny when compared with NP group. In addition, maternal low-protein diet induced a significant decrease in enzymatic antioxidant capacity (37.8% decrease in superoxide dismutase activity; 42% decrease in catalase activity; 44.8% decrease in glutathione-S-transferase activity; 47.9% decrease in glutathione reductase; 25.7% decrease in glucose-6 phosphate dehydrogenase) and glutathione level (34.8% decrease) when compared with control. From these findings, we hypothesize that an increased production of ROS and decrease in antioxidant activity levels induced by protein restriction during development could potentiate the progression of metabolic and cardiac diseases in adulthood.


Assuntos
Dieta com Restrição de Proteínas , Mitocôndrias/fisiologia , Miocárdio/metabolismo , Estresse Oxidativo , Fatores Etários , Animais , Feminino , Masculino , Gravidez , Ratos , Ratos Wistar
14.
Artigo em Português | LILACS | ID: lil-724203

RESUMO

Objetivo: este estudo longitudinal retrospectivo objetivou avaliar se existe relação entre o surgimento de manchas de esmalte em pré-molares, após o tratamento endodôntico dos seus antecessores molares decíduos.Métodos: as crianças submetidas à pesquisa, pacientes do Instituto de Medicina Integral Professor Fernando Figueira (IMIP), desde a mais tenra idade, foram localizados, juntamente com seus prontuários, e agrupados igualmente em três grupos conforme avaliação: (1) pré-molares sucessores de dentes decíduos que foram submetidos ao tratamento endodôntico com sessão única de Formocresol; (2) pré-molares sucessores de dentes decíduos que foram submetidos ao tratamento endodôntico com CTZ; (3) pré-molares cujos molares decíduos antecessores não possuíam lesões de acometimento pulpar. Um único examinador, com o intuito de identificar manchas de esmalte, avaliou 180 pré-molares, sem conhecimento prévio do histórico clínico ao qual foram submetidos seus antecessores decíduos,utilizando inspeção visual conferindo um índice Cohen´s kappa = 0,90. O teste de Qui-quadrado de Person e o exato de Fisher foram utilizados para identificar as diferenças entre os grupos experimentais e entre os grupos experimentais e o controle, respectivamente, em relação ao surgimento de manchas. O nível de significância adotado nesse estudo foi de 5%. Resultados: foi identificado que 8,3% dos pré-molares tratados com Formocresol e 11,7% tratados com o CTZ apresentaram algum tipo de mancha no esmalte (p>0.05), no entanto, não foram detectadas manchas nos dentes do grupo controle (p<0.05). Conclusão: quando os dentes antecessores decíduos foram submetidos à terapia endodôntico com Formocresol ou CTZ, houve surgimento de manchas em pré-molares, não havendo, no entanto, diferença estatisticamente significante...


Objective: The aim of this longitudinal retrospective study was to investigate whether there is association of the presence of enamel stains in premolars after endodontic treatment of their primary molar predecessors. Method: The children of this research have been patients of the Integral Medicine Institute Professor Fernando Figueira (IMIP) since their earliest age. The children were localized, their clinical charts were retrieved, and three groups were formed according to the evaluation: (1) successor premolars of primary molars subjected to single-session endodontic treatment with formocresol; (2) successor premolars of primary molars subjected to endodontic treatment with CTZ paste; and (3) successor premolars of primary molars that had no previous pulp involvement. A single examiner blinded to the clinical history of the primary molar predecessors evaluated 180 premolars for enamel stains by visual inspection, with a Cohen?s index kappa=0.90. Pearson?s square chi and Fisher?s exact tests were used to identify the differences among the experimental groups, and between the control and experimental groups, respectively, as regards the presence of enamel stains. The significance level was set at 5%. Results: 8.3% of the premolars that had the primary molar predecessors treated with formocresol and 11.7% of those treated with CTZ had some kind of enamel stain (p>0.05). There were no enamel stains in the teeth of the control group (p less than 0.05). Conclusion: When the primary molar predecessors were subjected to endodontic treatment with both formocresol and CTZ, enamel stains developed in the premolars, though without statistically significant difference...


Assuntos
Humanos , Criança , Dente Decíduo/lesões , Esmalte Dentário , Formocresóis/farmacologia , Pulpotomia/métodos , Distribuição de Qui-Quadrado , Endodontia/métodos
15.
Mutat Res ; 747(1): 93-97, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22579796

RESUMO

OBJECTIVE: To investigate whether formocresol, in Buckley's original formulation, used for pulp therapy of deciduous teeth, can have a genotoxic effect. Genotoxicity was tested in lymphocyte cultures from the peripheral blood of children aged 5-10y, in Recife, Pernambuco, Brazil. This was a case-control study. The sample comprised 40 children who had primary teeth with non-vital pulps. Two venous blood samples (6-8ml) were collected from each child, the first prior to pulp therapy (control group) and the second 24h after pulp therapy (experimental group). Lymphocyte cultures were grown in 78% RPMI 1640 medium, 20% fetal bovine serum, 2% phytohemagglutinin. The lymphocytes were assessed for chromosomal aberrations; each sample involved analysis of 100 metaphases. There was a statistically significant difference between the control and treated groups for the isochromatid gap (p<0.001), chromatid break (p<0.009), isochromatid break (p<0.046), other chromosomal alterations (p<0.001), and for total aberrations. In view of these results, caution in the use of formocresol in pediatric dentistry is recommended.


Assuntos
Capeamento da Polpa Dentária/efeitos adversos , Formocresóis/toxicidade , Mutagênicos/toxicidade , Dente Decíduo , Estudos de Casos e Controles , Criança , Pré-Escolar , Aberrações Cromossômicas , Feminino , Humanos , Masculino
16.
J Ethnopharmacol ; 142(1): 206-12, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22564358

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Species of Chresta genus- are recognized by the population of northeastern Brazil as traditional herbs used to treat gastric diseases and other disorders. AIM OF THE STUDY: This work aimed to find out the action mechanism of Chresta martii hydro alcoholic extract gastro protective effect in the model of ethanol-induced gastropathy. MATERIAL AND METHODS: Gastropathy was assessed by percentual damaged area determination in photographs of mice opened stomachs. Fasted mice treated with ethanol 99.9% (0.2 ml/animal, p.o.) were pre-treated with Chresta martii hydro alcoholic extract (HAE) (50, 100 or 200 mg/kg, p.o.), ranitidine (80 mg/kg, p.o.) or saline (5 ml/kg; p.o.) in different experimental sets, in which pharmacological tools (naloxone, indomethacin, N(ω)-Nitro-L-arginine methyl ester hydrochloride (L-NAME) or yohimbine) were added in order to clarify a possible action mechanism. Animals were sacrificed 30 min after ethanol challenge to stomach analysis. Determination of non-protein sulfhydryl groups and tissue hemoglobin, besides histological assessment (H&E) were taken to fully characterize the HAE gastro protective effect. RESULTS: HAE (100 and 200 mg/kg) was able to protect mucosa against ethanol gastropathy in presence of three (naloxone, indomethacin and L-NAME) of four antagonist/inhibitor tools. The HAE effect was reversed only by yohimbine, showing the alpha-2 adrenoceptors participation on gastro protective effect of this extract. HAE histological characteristics, NP-SH and Hb were compatible with the protective effects. CONCLUSIONS: HAE possesses gastroprotective effects in an ethanol-induced gastropathy model in mice, corroborating the traditional use of this family of plants to treat gastric disorders. This activity is mediated by alpha-2 adrenoceptors activation, but not by nitric oxide release, opioid receptor activation or prostaglandin synthesis. HAE also has antioxidant activity that is thought to either play a role in this biological activity or to be a byproduct of alpha-2 adrenergic complex activation.


Assuntos
Asteraceae , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/uso terapêutico , Receptores Adrenérgicos alfa 2/metabolismo , Gastropatias/tratamento farmacológico , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Analgésicos Opioides , Animais , Clonidina/farmacologia , Etanol , Flores , Hemoglobinas/metabolismo , Masculino , Camundongos , Óxido Nítrico , Folhas de Planta , Prostaglandinas , Gastropatias/induzido quimicamente , Gastropatias/metabolismo , Gastropatias/patologia , Compostos de Sulfidrila/metabolismo
17.
Eur J Pharm Sci ; 46(1-2): 56-63, 2012 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-22366113

RESUMO

AIM: The intent of this study is to examine whether intrauterine malnutrition provokes alterations in the progression of the acute and subchronic inflammatory response, and its influence on the pharmacological effect of indomethacin. METHODS DESIGN: Rat offspring of dams which were fed from the first day of their gestation to term receiving a balanced diet (Labina) or a basic regional diet (BRD) from northeastern Brazil. According to their dams, the offspring were divided in two groups: Control-N (nourished) and BRD-g (undernourished during gestation). At 2 months of age, the animals were divided into groups (n=06): (1) Animals that were subjected to carrageenan or (2) zymosan-induce paw edema (acute inflammation models) and (3) Animals that were subjected to cotton pellet-induced granuloma (subchronic inflammation model). All animals received (saline 0.9%; p.o.). Another set of adult offspring was submitted to the same procedure as above, but instead of saline they received (via gavage) a single oral dose of indomethacin (10mg/kg) for the animals subjected to acute inflammation models or 2mg/kg for seven consecutive days for the animals subjected to subchronic inflammation model. The animals were further divided in two groups: Control-NI (Control-N treated with indomethacin), and BRDI-g (BRD-g treated with indomethacin). The volume of hind paw swelling (mL) was measured at time zero (before), 30, 60, 120, 180 and 240 min after carrageenan or zymosan injection. In the subchronic model of inflammation, the pellets were removed and dried to a constant weight. Hind paw swelling, weight of granuloma, blood albumin and C-reactive protein (CRP) levels, leukocyte count and cytokine levels were evaluated as indicators of inflammation. RESULTS: Undernutrition during pregnancy caused fetal growth retardation which was shown in terms of low birth weight (5.38±0.28), when compared to the Control-N (7.26±0.64) group. The volume of paw edema, the serum levels of CRP and albumin and cytokine levels were lower than those in the BRD-g group when compared to those in the Control-N groups, in both models of acute inflammation studied. However, no difference was found in the total leukocyte count. When compared to the respective groups treated with saline (Control-N and BRD-g), the antiinflammatory effect of indomethacin in the animals of BRDI-g groups was lower than in the Control-NI groups, in the model of acute inflammation. In the model of subchronic inflammation, the pharmacological effect of indomethacin was effective only in nourished animals. CONCLUSION: Malnutrition in the early stages of development attenuated the severity of the acute inflammatory response, but there was no statistically significant change in subchronic inflammation induced by granulomatous lesion. Our findings provide impetus for larger trials to assess the influence of undernutrition on the pharmacokinetics/pharmacodynamics of indomethacin.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Transtornos da Nutrição Fetal/metabolismo , Indometacina/farmacocinética , Inflamação/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Análise de Variância , Ração Animal , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Peso ao Nascer , Proteína C-Reativa/análise , Carragenina/efeitos adversos , Edema/induzido quimicamente , Feminino , Retardo do Crescimento Fetal , Granuloma/induzido quimicamente , Indometacina/administração & dosagem , Inflamação/induzido quimicamente , Interleucina-6/análise , Contagem de Leucócitos , Masculino , Gravidez , Ratos , Ratos Wistar , Albumina Sérica/análise , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise , Zimosan/efeitos adversos
18.
J. physiol. biochem ; 67(3): 371-379, sept. 2011. tab
Artigo em Inglês | IBECS | ID: ibc-122602

RESUMO

No disponible


Currently, there are no reports in the literature demonstrating any animal model that ingests one of the fattiest animal food source, the bovine brain. We hypothesized that a high-fat diet (HFD), based on dried bovine brain, could be used to develop an animal model possessing a spectrum of insulin resistance-related features. The HFD was formulated with 40% dried bovine brain plus 16.4% butter fat, prepared in-house. Furthermore, the diet contained 52% calories as fat and 73% of total fatty acids were saturated. Swiss mice weighing about 40 g were assigned to two dietary groups (n = 6/group), one group received a standard chow diet and the other was given HFD for 3 months. The body weight and biochemical parameters of the animals were measured initially and at monthly intervals until the end of the experiment. Animals fed on a HFD showed a significant increase in the body and adipose tissue weight, serum total cholesterol and triglyceride levels, when compared with mice fed on the control diet. Additionally, the HFD group showed higher circulating levels of liver transaminases, such as alanine aminotransferase and aspartate aminotransferase, compared with the control group. Finally, to illustrate the usefulness of this model, we report that the HFD induced mild hyperglycemia, fasting hyperinsulinemia, and increased the homeostasis model of assessment (HOMA-IR), in comparison with the control group. In conclusion, our results show that HFD, based on dried bovine brain, causes insulin resistance-related metabolic disturbances. Thus, this may be a suitable model to study disturbances in energy metabolism and their consequences (AU)


Assuntos
Animais , Camundongos , Gorduras na Dieta/farmacocinética , Dislipidemias/fisiopatologia , Metabolismo Energético , Síndrome Metabólica/fisiopatologia , Modelos Animais de Doenças , Fatores de Risco
19.
Br J Nutr ; 106(6): 845-51, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21736850

RESUMO

The objective of the present study was to investigate whether early undernutrition changes the chronic inflammatory response, so as to study its influence on pharmacological response to indomethacin. Rat offspring of dams fed from the first day of gestation to term or throughout the lactation period received a balanced diet (NN) or a basic regional diet (BRD) from northeast Brazil. According to their dams, the offspring were divided into three groups: NN; basic regional diet during gestation (BRD-g, undernourished during gestation); basic regional diet during gestation and lactation (BRD-gl, undernourished during gestation and lactation). At 2 months of age, Freund's adjuvant (0·2 ml) was inoculated into the plantar surface of the hind paw (day 0) of animals. All animals orally received saline (0·9 %) for 28 d. Another group of adult offspring was subjected to the same procedure as described above, but orally received indomethacin (2 mg/kg) instead of saline, and divided into three subgroups: NN treated with indomethacin (NNI); BRD-g treated with indomethacin (BRDI-g); BRD-gl treated with indomethacin (BRDI-gl). The hind paw volume was calculated on days 0 (initial paw volume), 7, 14 and 28. Hind paw swelling, blood albumin and C-reactive protein (CRP) levels and leucocyte counts were evaluated as markers of inflammation. Reduced hind paw swelling and the blood levels of serum albumin and CRP were found in the BRD-g and BRD-gl offspring. However, no difference was found in the leucocyte count. Compared with their respective saline-treated groups (NN, BRD-g and BRD-gl), the anti-inflammatory effect of indomethacin was lower in the BRDI-g and BRDI-gl groups than in the NNI group. We conclude that early undernutrition attenuated the chronic inflammatory response and the anti-inflammatory effect of indomethacin.


Assuntos
Indometacina/farmacologia , Inflamação , Desnutrição/complicações , Ração Animal , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Bioética , Proteína C-Reativa/metabolismo , Feminino , Lactação , Masculino , Exposição Materna , Gravidez , Prenhez , Ratos , Ratos Wistar , Fatores de Tempo
20.
J Physiol Biochem ; 67(3): 371-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21437730

RESUMO

Currently, there are no reports in the literature demonstrating any animal model that ingests one of the fattiest animal food source, the bovine brain. We hypothesized that a high-fat diet (HFD), based on dried bovine brain, could be used to develop an animal model possessing a spectrum of insulin resistance-related features. The HFD was formulated with 40% dried bovine brain plus 16.4% butter fat, prepared in-house. Furthermore, the diet contained 52% calories as fat and 73% of total fatty acids were saturated. Swiss mice weighing about 40 g were assigned to two dietary groups (n=6/group), one group received a standard chow diet and the other was given HFD for 3 months. The body weight and biochemical parameters of the animals were measured initially and at monthly intervals until the end of the experiment. Animals fed on a HFD showed a significant increase in the body and adipose tissue weight, serum total cholesterol and triglyceride levels, when compared with mice fed on the control diet. Additionally, the HFD group showed higher circulating levels of liver transaminases, such as alanine aminotransferase and aspartate aminotransferase, compared with the control group. Finally, to illustrate the usefulness of this model, we report that the HFD induced mild hyperglycemia, fasting hyperinsulinemia, and increased the homeostasis model of assessment (HOMA-IR), in comparison with the control group. In conclusion, our results show that HFD, based on dried bovine brain, causes insulin resistance-related metabolic disturbances. Thus, this may be a suitable model to study disturbances in energy metabolism and their consequences.


Assuntos
Encéfalo , Gorduras na Dieta/administração & dosagem , Dislipidemias/etiologia , Resistência à Insulina , Tecido Adiposo/patologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Glicemia/metabolismo , Peso Corporal , Bovinos , Dessecação , Modelos Animais de Doenças , Ingestão de Energia , Insulina/sangue , Lipídeos/sangue , Masculino , Camundongos , Tamanho do Órgão
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