RESUMO
Type 1 diabetes (T1D) is the result of the selective destruction of the pancreatic ß-cells by T cells of the immune system. Although spleen is a secondary lymphoid organ, it is also involved in the T1D pathogenesis. However, the alterations in a variety of cellular processes of this disease need to be further understood. We aimed to analyze the benefits of resveratrol, and its complexed form on diabetic complications in the spleen of rats. To this end, we investigated important enzymes of phosphoryl transfer network, and Na+, K+-ATPase activity. Wistar rats were divided into non-diabetic groups: Control, Ethanol, Resveratrol, Hydroxypropyl-ß-cyclodextrin, Resveratrol-hydroxypropyl-ß-cyclodextrin, and diabetic groups with the same treatments. Diabetes was induced by a single dose of 60 mg/kg of streptozocin intraperitoneally, and treatments by intragastric gavage once daily for 60 days. Hyperglycemia reduced creatine kinase activity, which was reversed by the administration of resveratrol. Na+, K+-ATPase activity was greatly affected, but it was reversed by resveratrol and resveratrol-hydroxypropyl-ß-cyclodextrin. This suggest an energetic imbalance in the spleen of diabetic rats, and in case this also occurs in the diabetic patients, it is possible that resveratrol supplementation could be beneficial to the better functioning of the spleen in diabetic patients.
Assuntos
2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Antioxidantes/farmacologia , Diabetes Mellitus Experimental/metabolismo , Resveratrol/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Baço/metabolismo , Animais , Antioxidantes/metabolismo , Glicemia/análise , Peso Corporal , Creatina Quinase/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Metabolismo Energético/efeitos dos fármacos , Hiperglicemia/metabolismo , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , EstreptozocinaRESUMO
ABSTRACT Considering that thiol-containing enzymes like kinases are critical for several metabolic pathways and energy homeostasis, we investigated the effects of cystine dimethyl ester and/or cysteamine administration on kinases crucial for energy metabolism in the kidney of Wistar rats. Animals were injected twice a day with 1.6 µmol/g body weight cystine dimethyl ester and/or 0.26 µmol/g body weight cysteamine from the 16th to the 20th postpartum day and euthanized after 12 hours. Pyruvate kinase, adenylate kinase, creatine kinase activities and thiol/disulfide ratio were determined. Cystine dimethyl ester administration reduced thiol/disulfide ratio and inhibited the kinases activities. Cysteamine administration increased the thiol/disulfide ratio and co-administration with cystine dimethyl ester prevented the inhibition of the enzymes. Regression between the thiol/disulfide ratio, and the kinases activities were significant. These results suggest that redox status may regulate energy metabolism in the rat kidney. If thiol-containing enzymes inhibition and oxidative stress occur in patients with cystinosis, it is possible that lysosomal cystine depletion may not be the only beneficial effect of cysteamine administration, but also its antioxidant and thiol-protector effect.
Assuntos
Animais , Compostos de Sulfidrila , Cisteamina/farmacologia , Cistina/análogos & derivados , Dissulfetos , Homeostase/efeitos dos fármacos , Rim/efeitos dos fármacos , Adenilato Quinase/análise , Adenilato Quinase/efeitos dos fármacos , Reprodutibilidade dos Testes , Ratos Wistar , Creatina Quinase/análise , Creatina Quinase/efeitos dos fármacos , Cistina/farmacologia , Eliminadores de Cistina/farmacologiaRESUMO
Considering that thiol-containing enzymes like kinases are critical for several metabolic pathways and energy homeostasis, we investigated the effects of cystine dimethyl ester and/or cysteamine administration on kinases crucial for energy metabolism in the kidney of Wistar rats. Animals were injected twice a day with 1.6 µmol/g body weight cystine dimethyl ester and/or 0.26 µmol/g body weight cysteamine from the 16th to the 20th postpartum day and euthanized after 12 hours. Pyruvate kinase, adenylate kinase, creatine kinase activities and thiol/disulfide ratio were determined. Cystine dimethyl ester administration reduced thiol/disulfide ratio and inhibited the kinases activities. Cysteamine administration increased the thiol/disulfide ratio and co-administration with cystine dimethyl ester prevented the inhibition of the enzymes. Regression between the thiol/disulfide ratio, and the kinases activities were significant. These results suggest that redox status may regulate energy metabolism in the rat kidney. If thiol-containing enzymes inhibition and oxidative stress occur in patients with cystinosis, it is possible that lysosomal cystine depletion may not be the only beneficial effect of cysteamine administration, but also its antioxidant and thiol-protector effect.
Assuntos
Cisteamina/farmacologia , Cistina/análogos & derivados , Dissulfetos , Homeostase/efeitos dos fármacos , Rim/efeitos dos fármacos , Compostos de Sulfidrila , Adenilato Quinase/análise , Adenilato Quinase/efeitos dos fármacos , Animais , Creatina Quinase/análise , Creatina Quinase/efeitos dos fármacos , Cistina/farmacologia , Eliminadores de Cistina/farmacologia , Rim/enzimologia , Piruvato Quinase/análise , Piruvato Quinase/efeitos dos fármacos , Distribuição Aleatória , Ratos Wistar , Valores de Referência , Reprodutibilidade dos TestesRESUMO
Hypoxanthine is the major purine involved in the salvage pathway of purines in the brain. High levels of hypoxanthine are characteristic of Lesch-Nyhan Disease. Since hypoxanthine is a purine closely related to ATP formation, the aim of this study was to investigate the effect of intrastriatal hypoxanthine administration on neuroenergetic parameters (pyruvate kinase, succinate dehydrogenase, complex II, cytochrome c oxidase, and ATP levels) and mitochondrial function (mitochondrial mass and membrane potential) in striatum of rats. We also evaluated the effect of cell death parameters (necrosis and apoptosis). Wistar rats of 60 days of life underwent stereotactic surgery and were divided into two groups: control (infusion of saline 0.9%) and hypoxanthine (10 µM). Intrastriatal hypoxanthine administration did not alter pyruvate kinase activity, but increased succinate dehydrogenase and complex II activities and diminished cytochrome c oxidase activity and immunocontent. Hypoxanthine injection decreased the percentage of cells with mitochondrial membrane label and increased mitochondrial membrane potential labeling. There was a decrease in the number of live cells and an increase in the number of apoptotic cells by caused hypoxanthine. Our findings show that intrastriatal hypoxanthine administration altered neuroenergetic parameters, and caused mitochondrial dysfunction and cell death by apoptosis, suggesting that these processes may be associated, at least in part, with neurological symptoms found in patients with Lesch-Nyhan Disease.
Assuntos
Envelhecimento/patologia , Corpo Estriado/patologia , Metabolismo Energético , Hipoxantina/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Creatina Quinase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hipoxantina/administração & dosagem , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Piruvato Quinase/metabolismo , Ratos Wistar , Succinato Desidrogenase/metabolismoRESUMO
Acai has been used by the population due to its high nutritional value and its benefits to health, such as its antioxidant properties. The aim of this study was to evaluate the protective effect of acai frozen pulp on oxidative stress parameters in cerebral cortex, hippocampus and cerebellum of Wistar rats treated with carbon tetrachloride (CCl4). Thirty male Wistar rats (90-day-old) were orally treated with water or acai frozen pulp for 14 days (7 µL/g). On the 15th day, half of the animals received treatment with mineral oil and the other half with CCl4 (3.0 mL/kg). The cerebral cortex, hippocampus and cerebellum were dissected and used for analysis of creatine kinase activity (CK), thiobarbituric acid reactive substances (TBARS), carbonyl, sulfhydryl, and the activity of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). Statistical analysis was performed by ANOVA followed by Tukey's post-test. CCl4 was able to inhibit CK activity in all tissues tested and to provoke lipid damage in cerebral cortex and cerebellum, and protein damage in the three tissues tested. CCl4 enhanced CAT activity in the cerebral cortex, and inhibited CAT activity in the hippocampus and cerebellum and reduced SOD activity in all tissues studied. Acai frozen pulp prevented the inhibition of CK, TBARS, carbonyl and CAT activity in all brain structures and only in hippocampus for SOD activity. Therefore, acai frozen pulp has antioxidant properties and maybe could be useful in the treatment of some diseases that affect the central nervous system that are associated with oxidative damage.
Assuntos
Encéfalo/metabolismo , Euterpe , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/prevenção & controle , Estresse Oxidativo/fisiologia , Extratos Vegetais/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Congelamento , Frutas , Falência Hepática Aguda/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Resultado do TratamentoRESUMO
In heart failure (HF), there is an imbalance between the production of reactive oxygen species and the synthesis of antioxidant enzymes, causing damage to the cardiovascular function and increased susceptibility to DNA damage. The aim of this study was to evaluate the influence of low-level laser therapy (LLLT) on parameters of oxidative stress and DNA damage in skeletal muscle and plasma of rats with HF. Wistar rats were allocated into six groups: "placebo" HF rats (P-HF, n = 9), "placebo" Sham rats (P-sham, n = 8), HF rats at a dose 3 J/cm(2) of LLLT (3 J/cm(2)-HF, n = 8), sham rats at a dose 3 J/cm(2) of LLLT (3 J/cm(2)-sham, n = 8), HF rats at a dose 21 J/cm(2) of LLLT (21 J/cm(2)-HF, n = 8) and sham rats at a dose 21 J/cm(2) of LLLT (21 J/cm(2)-sham, n = 8). Animals were submitted to a LLLT protocol for 10 days at the right gastrocnemius muscle. Comparison between groups showed a significant reduction in superoxide dismutase (SOD) activity in the 3 J/cm(2)-HF group (p = 0.03) and the 21 J/cm(2)-HF group (p = 0.01) compared to the P-HF group. 2',7'-Dihydrodichlorofluorescein (DCFH) oxidation levels showed a decrease when comparing 3 J/cm(2)-sham to P-sham (p = 0.02). The DNA damage index had a significant increase either in 21 J/cm(2)-HF or 21 J/cm(2)-sham in comparison to P-HF (p = 0.004) and P-sham (p = 0.001) and to 3 J/cm(2)-HF (p = 0.007) and 3 J/cm(2)-sham (p = 0.037), respectively. Based on this, laser therapy appears to reduce SOD activity and DCFH oxidation levels, changing the oxidative balance in the skeletal muscle of HF rats. Otherwise, high doses of LLLT seem to increase DNA damage.
Assuntos
Insuficiência Cardíaca/radioterapia , Terapia com Luz de Baixa Intensidade/métodos , Músculo Esquelético/efeitos da radiação , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Dano ao DNA , Fluoresceínas/química , Glutationa Peroxidase/metabolismo , Hemodinâmica , Inflamação/metabolismo , Lasers , Masculino , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismoRESUMO
The reduction in the secretion of ovarian hormones, principally estrogen, is a consequence of menopause. Estrogens act primarily as female sex hormones, but also exert effects on different physiological systems including the central nervous system. The treatment normally used to reduce the symptoms of menopause is the hormone therapy, which seems to be effective in treating symptoms, but it may be responsible for adverse effects. Based on this, there is an increasing demand for alternative therapies that minimize signs and symptoms of menopause. In the present study we investigated the effect of ovariectomy and/or physical exercise on the activities of energy metabolism enzymes, such as creatine kinase (cytosolic and mitochondrial fractions), pyruvate kinase, succinate dehydrogenase, complex II, cytochrome c oxidase, as well as on ATP levels in the hippocampus of adult rats. Adult female Wistar rats with 90 days of age were subjected to ovariectomy (an animal model widely used to mimic the postmenopausal changes). Thirty days after the procedure, the rats were submitted to the exercise protocol, which was performed three times a week for 30 days. Twelve hours after the last training session, the rats were decapitated for subsequent biochemical analyzes. Results showed that ovariectomy did not affect the activities of pyruvate kinase, succinate dehydrogenase and complex II, but decreased the activities of creatine kinase (cytosolic and mitochondrial fractions) and cytochrome c oxidase. ATP levels were also reduced. Exercise did not produce the expected results since it was only able to partially reverse the activity of creatine kinase cytosolic fraction. The results of this study suggest that estrogen deficiency, which occurs as a result of ovariectomy, affects generation systems and energy homeostasis, reducing ATP levels in hippocampus of adult female rats.
Assuntos
Trifosfato de Adenosina/metabolismo , Creatina Quinase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hipocampo/metabolismo , Ovariectomia , Condicionamento Físico Animal/fisiologia , Animais , Feminino , Piruvato Quinase/metabolismo , Ratos , Ratos Wistar , Succinato Desidrogenase/metabolismoRESUMO
Homocystinuria is a neurometabolic disease caused by a severe deficiency of cystathionine beta-synthase activity, resulting in severe hyperhomocysteinemia. Affected patients present several symptoms including a variable degree of motor dysfunction. In this study, we investigated the effect of chronic hyperhomocysteinemia on the cell viability of the mitochondrion, as well as on some parameters of energy metabolism, such as glucose oxidation and activities of pyruvate kinase, citrate synthase, isocitrate dehydrogenase, malate dehydrogenase, respiratory chain complexes and creatine kinase in gastrocnemius rat skeletal muscle. We also evaluated the effect of creatine on biochemical alterations elicited by hyperhomocysteinemia. Wistar rats received daily subcutaneous injections of homocysteine (0.3-0.6 µmol/g body weight) and/or creatine (50 mg/kg body weight) from the 6th to the 28th days of age. The animals were decapitated 12 h after the last injection. Homocysteine decreased the cell viability of the mitochondrion and the activities of pyruvate kinase and creatine kinase. Succinate dehydrogenase was increased other evaluated parameters were not changed by this amino acid. Creatine, when combined with homocysteine, prevented or caused a synergistic effect on some changes provoked by this amino acid. Creatine per se or creatine plus homocysteine altered glucose oxidation. These findings provide insights into the mechanisms by which homocysteine exerts its effects on skeletal muscle function, more studies are needed to elucidate them. Although creatine prevents some alterations caused by homocysteine, it should be used with caution, mainly in healthy individuals because it could change the homeostasis of normal physiological functions.
Assuntos
Creatina/farmacologia , Homocisteína/metabolismo , Hiper-Homocisteinemia/metabolismo , Músculo Esquelético/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Ciclo do Ácido Cítrico , Creatina/uso terapêutico , Sinergismo Farmacológico , Metabolismo Energético , Feminino , Glucose/metabolismo , Homocisteína/farmacologia , Hiper-Homocisteinemia/tratamento farmacológico , Hiper-Homocisteinemia/patologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Oxirredução , Ratos , Ratos WistarRESUMO
Phenylketonuria is a recessive autosomal disorder that is caused by a deficiency in the activity of phenylalanine-4-hydroxylase, which converts phenylalanine to tyrosine, leading to the accumulation of phenylalanine and its metabolites phenyllactic acid, phenylacetic acid, and phenylpyruvic acid in the blood and tissues of patients. Phenylketonuria is characterized by severe neurological symptoms, but the mechanisms underlying brain damage have not been clarified. Recent studies have shown the involvement of oxidative stress in the neuropathology of hyperphenylalaninemia. Glucose-6-phosphate dehydrogenase plays an important role in antioxidant defense because it is the main source of reduced nicotinamide adenine dinucleotide phosphate (NADPH), providing a reducing power that is essential in protecting cells against oxidative stress. Therefore, the present study investigated the in vitro effect of phenylalanine (0.5, 1, 2.5, and 5 mM) and its metabolites phenyllactic acid, phenylacetic acid, and phenylpyruvic acid (0.2, 0.6, and 1.2 mM) on the activity of enzymes of the pentose phosphate pathway, which is involved in the oxidative phase in rat brain homogenates. 6-Phosphogluconate dehydrogenase activity was not altered by any of the substances tested. Phenylalanine, phenyllactic acid, and phenylacetic acid had no effect on glucose-6-phosphate dehydrogenase activity. Phenylpyruvic acid significantly reduced glucose-6-phosphate dehydrogenase activity without pre-incubation and after 1 h of pre-incubation with the homogenates. The inhibition of glucose-6-phosphate dehydrogenase activity caused by phenylpyruvic acid could elicit an impairment of NADPH production and might eventually alter the cellular redox status. The role of phenylpyruvic acid in the pathophysiological mechanisms of phenylketonuria remains unknown.
Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Glucosefosfato Desidrogenase/antagonistas & inibidores , Glucosefosfato Desidrogenase/metabolismo , Ácidos Fenilpirúvicos/farmacologia , Animais , Ratos , Ratos WistarRESUMO
Selenium (Se) is an essential mineral for mammals. It is a nutrient related to the complex metabolic and enzymatic functions. Although Se has important physiological functions in the cells, organic compounds of Se can be extremely toxic, and may affect the central nervous system. This study aims to investigate the effect of the chronic treatment with the vinyl chalcogenide 3-methyl-1-phenyl-2-(phenylseleno)oct-2-en-1-one on some parameters of oxidative stress in the brain of rats. Animals received the vinyl chalcogenide (125, 250 or 500 µg/kg body weight) intraperitoneally once a day during 30 days. The cerebral cortex, the hippocampus, and the cerebellum were dissected and homogenized in KCl. Afterward, thiobarbituric acid reactive substances (TBARS), carbonyl, sulfhydryl, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured in the brain. Results showed that the organoselenium enhanced TBARS in the cerebral cortex of rats but the compound was not able to change carbonyl levels. Furthermore, the organoselenium reduced thiol groups measured by the sulfhydryl assay in all tissues studied. The activity of the antioxidant enzyme CAT was increased by the organochalcogen in the cerebral cortex and in the cerebellum, and the activity of SOD was increased in the hippocampus. On the other hand, the activity of the antioxidant enzyme GPx was reduced in all brain structures. Our findings indicate that this organoselenium compound induces oxidative stress in different brain regions of rats, corroborating to the fact that this tissue is a potential target for organochalcogen action.