RESUMO
The aim of this study was to investigate the ability of tannic acid (TA) in preventing memory deficits and neurochemical alterations observed in a model for Sporadic Dementia of Alzheimer's Type. Rats were treated with TA (30 mg/kg) daily for 21 days, and subsequently received intracerebroventricular injection of streptozotocin (STZ). We observed that STZ induced learning and memory impairments; however, treatment with TA was able to prevent these effects. In cerebral cortex and hippocampus, STZ induced an increase in acetylcholinesterase activity, reduced Na+, K+-ATPase activity and induced oxidative stress increasing thiobarbituric acid-reactive substances, nitrites and reactive oxygen species levels and reducing the activity of antioxidant enzymes. Treatment with TA was able in prevent the major of these neurochemical alterations. In conclusion, TA prevented memory deficits, alterations in brain enzyme activities, and oxidative damage induced by STZ. Thus, TA can be an interesting strategy in the prevention of Sporadic Alzheimer's Disease.
Assuntos
Doença de Alzheimer , Acetilcolinesterase/metabolismo , Adenosina Trifosfatases , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Animais , Modelos Animais de Doenças , Aprendizagem em Labirinto , Oxirredução , Estresse Oxidativo , Ratos , Ratos Wistar , Estreptozocina/toxicidade , TaninosRESUMO
Abstract Intense physical activity can increase oxidative stress and muscle damage in, causing fatigue and injury. Graduated compression stockings (GCS) can decrease these deleterious effects. The aim was to determine the acute effects of GCS on muscle damage and oxidative stress (OS) in garbage collectors. Thirteen garbage collectors, 25.4±5.2 years, participated using GCS or placebo stockings. Blood samples were collected at pre and post a working day and after 16 hours of rest. Markers of OS and muscle damage were evaluated. Two-way ANOVA (two conditions and two moments) was used for the analysis of the outcomes No significant differences were found for creatine kinase, catalase and glutathione peroxidase between the time and groups. There was a significant difference for the total thiol content and superoxide dismutase only in the control group (pre and post, p = 0.004). The use of GCS exerted acute protection against the increase of markers of OS, but did not contribute to attenuate muscle damage.
Resumo Atividade física intensa pode aumentar o estresse oxidativo e danos musculares, causando fadiga e lesões. As meias de compressão graduada (MCG) podem diminuir esses efeitos deletérios. O objetivo foi determinar os efeitos agudos da MCG no dano muscular e estresse oxidativo (EO) em coletores de lixo. Treze coletores de lixo, 25,4 ± 5,2 anos, participaram usando MCG ou placebo. As amostras de sangue foram coletadas antes e após um dia útil e após 16 horas de descanso. Marcadores de EO e dano muscular foram avaliados. ANOVA de duas vias (duas condições e dois momentos) foi usada para á análise dos resultados. Não foram encontradas diferenças significativas para creatina quinase, catalase e glutationa peroxidase entre o tempo e os grupos. Houve uma diferença significativa para o conteúdo total tiólico e superóxido dismutase apenas no grupo controle (pré e pós, p = 0,004). O uso de MCG exerceu proteção aguda contra o aumento de marcadores de EO, mas não contribuiu para atenuar danos musculares
RESUMO
BACKGROUND: Glioblastomas are the most devastating brain tumor characterized by chemoresistance development and poor prognosis. Macrophages are a component of tumor microenvironment related to glioma malignancy. The relation among inflammation, innate immunity and cancer is accepted; however, molecular and cellular mechanisms mediating this relation and chemoresistance remain unresolved. OBJECTIVE: Here we evaluated whether glioma sensitive or resistant to temozolomide (TMZ) modulate macrophage polarization and inflammatory pathways associated. The impact of glioma-macrophage crosstalk on glioma proliferation was also investigated. METHODS: GL261 glioma chemoresistance was developed by exposing cells to increasing TMZ concentrations over a period of 6months. Mouse peritoneal macrophages were exposed to glioma-conditioned medium or co-cultured directly with glioma sensitive (GL) or chemoresistant (GLTMZ). Macrophage polarization, in vitro and in vivo glioma proliferation, redox parameters, ectonucleotidase activity and ATP cytotoxicity were performed. RESULTS: GLTMZ cells were more effective than GL in induce M2-like macrophage polarization and in promote a strong immunosuppressive environment characterized by high IL-10 release and increased antioxidant potential, which may contribute to glioma chemoresistance and proliferation. Interestingly, macrophage-GLTMZ crosstalk enhanced in vitro and in vivo proliferation of chemoresistant cells, decreased ectonucleotidase activities, which was followed by increased macrophage sensitivity to ATP induced death. CONCLUSIONS: Results suggest a differential macrophage modulation by GLTMZ cells, which may favor the maintenance of immunosuppressive tumor microenvironment and glioma proliferation. GENERAL SIGNIFICANCE: The induction of immunosuppressive environment and macrophage education by chemoresistant gliomas may be important for tumor recovery after chemotherapy and could be considered to overcome chemoresistance development.
Assuntos
Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Glioma/tratamento farmacológico , Inflamação/tratamento farmacológico , Animais , Antineoplásicos Alquilantes/administração & dosagem , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Polaridade Celular/efeitos dos fármacos , Dacarbazina/administração & dosagem , Modelos Animais de Doenças , Glioma/metabolismo , Glioma/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Receptores Purinérgicos/genética , Temozolomida , Microambiente Tumoral/efeitos dos fármacosRESUMO
OBJECTIVE: Here we investigated the impact of chronic high-intensity interval training (HIIT) and caffeine consumption on the activities of Na+-K+-ATPase and enzymes of the antioxidant system, as well as anxiolytic-like behaviour in the rat brain. METHODS: Animals were divided into groups: control, caffeine (4â mg/kg), caffeine (8â mg/kg), HIIT, HIIT plus caffeine (4â mg/kg) and HIIT plus caffeine (8â mg/kg). Rats were trained three times per week for 6 weeks, and caffeine was administered 30 minutes before training. We assessed the anxiolytic-like behaviour, Na+-K+-ATPase, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities, levels of reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) in the brain. RESULTS AND DISCUSSION: HIIT-induced anxiolytic-like behaviour increased Na+-K+-ATPase and GPx activities and TBARS levels, altered the activities of SOD and CAT in different brain regions, and decreased GSH levels. Caffeine, however, elicited anxiogenic-like behaviour and blocked HIIT effects. The combination of caffeine and HIIT prevented the increase in SOD activity in the cerebral cortex and GPx activity in three brain regions. Our results show that caffeine promoted anxiogenic behaviour and prevented HIIT-induced changes in the antioxidant system and Na+-K+-ATPase activities.
Assuntos
Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Cafeína/uso terapêutico , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
Methionine is an essential amino acid involved in critical metabolic process, and regulation of methionine flux through metabolism is important to supply this amino acid for cell needs. Elevation in plasma methionine commonly occurs due to mutations in methionine-metabolizing enzymes, such as methionine adenosyltransferase. Hypermethioninemic patients exhibit clinical manifestations, including neuronal and liver disorders involving inflammation and tissue injury, which pathophysiology is not completely established. Here, we hypothesize that alterations in macrophage inflammatory response may contribute to deleterious effects of hypermethioninemia. To this end, macrophage primary cultures were exposed to methionine (1 mM) and/or its metabolite methionine sulfoxide (0.5 mM), and M1/proinflammatory or M2/anti-inflammatory macrophage polarization was evaluated. In addition, inflammation-related pathways including oxidative stress parameters, as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities; reactive oxygen species (ROS) production, and purinergic signaling, as ATP/ADP/AMPase activities, were investigated. Methionine and/or methionine sulfoxide induced M1/classical macrophage activation, which is related to proinflammatory responses characterized by increased iNOS activity and TNF-α release. Further experiments showed that treatments promoted alterations on redox state of macrophages by differentially modulated SOD and CAT activities and ROS levels. Finally, methionine and/or methionine sulfoxide treatment also altered the extracellular nucleotide metabolism, promoting an increase of ATPase/ADPase activities in macrophages. In conclusion, these findings contribute to better understand the participation of proinflammatory responses in cell injury observed in hypermethioninemic patients.
Assuntos
Macrófagos/metabolismo , Metionina/análogos & derivados , Metionina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismoRESUMO
The antioxidant properties of two series of thiazolidinones and thiazinanones were reported. The novel six-membered thiazinanones were synthesized from the efficient multicomponent reaction of 2-picolylamine (2-aminomethylpyridine), arenaldehydes, and the 3-mercaptopropionic acid in moderate to excellent yields. These novel compounds were fully identified and characterized by NMR and GC-MS techniques. In vitro antioxidant activities of all compounds were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) tests. The antioxidant assays of thiobarbituric acid reactive species and total thiol content levels in the cerebral cortex and liver of rats were also performed. Thiazinanone 5a showed the best radical scavenging activity in DPPH and ABTS tests, as well as reduced lipid peroxidation and increased total thiol group in biological systems. Altogether, the results may be considered a good starting point for the discovery of a new radical scavenger.
Assuntos
Sequestradores de Radicais Livres , Compostos Heterocíclicos com 3 Anéis , Peroxidação de Lipídeos/efeitos dos fármacos , Animais , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Compostos Heterocíclicos com 3 Anéis/síntese química , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/farmacologia , Ratos , Ratos WistarRESUMO
The Biginelli reaction is a multicomponent reaction involving the condensation between an aldehyde, a ß-ketoester, and urea or thiourea, in the presence of an acid catalyst, producing dihydropyrimidinones (DHPMs). Owing to their important pharmacological properties, the DHPMs have been studied by many authors. However, most of the methodologies used for the synthesis of these compounds require drastic reaction conditions. In the current study, we report an efficient and clean procedure for preparing DHPMs by the use of citric acid or tartaric acid as a promoter of the Biginelli synthesis in ethanol as solvent. In addition, we have evaluated the antioxidant capacity of the compounds synthesized by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and the thiobarbituric acid-reactive species test. Two compounds presented antioxidant activity and also reduced lipid peroxidation at concentrations of 200 and 300 µM. In summary, we report an environmentally friendly procedure for the preparation of DHPMs and demonstrate the antioxidant capacity of some of the compounds.