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1.
Nutrients ; 14(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35683979

RESUMO

This study investigates whether ladder climbing (LC), as a model of resistance exercise, can reverse whole-body and skeletal muscle deleterious metabolic and inflammatory effects of high-fat (HF) diet-induced obesity in mice. To accomplish this, Swiss mice were fed for 17 weeks either standard chow (SC) or an HF diet and then randomly assigned to remain sedentary or to undergo 8 weeks of LC training with progressive increases in resistance weight. Prior to beginning the exercise intervention, HF-fed animals displayed a 47% increase in body weight (BW) and impaired ability to clear blood glucose during an insulin tolerance test (ITT) when compared to SC animals. However, 8 weeks of LC significantly reduced BW, adipocyte size, as well as glycemia under fasting and during the ITT in HF-fed rats. LC also increased the phosphorylation of AktSer473 and AMPKThr172 and reduced tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL1-ß) contents in the quadriceps muscles of HF-fed mice. Additionally, LC reduced the gene expression of inflammatory markers and attenuated HF-diet-induced NADPH oxidase subunit gp91phox in skeletal muscles. LC training was effective in reducing adiposity and the content of inflammatory mediators in skeletal muscle and improved whole-body glycemic control in mice fed an HF diet.


Assuntos
Resistência à Insulina , Treinamento Resistido , Tecido Adiposo/metabolismo , Animais , Glicemia/metabolismo , Dieta Hiperlipídica/efeitos adversos , Humanos , Resistência à Insulina/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Obesidade/terapia , Ratos
2.
Nutr Neurosci ; 25(5): 1066-1077, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33107813

RESUMO

OBJECTIVE: We investigated the influence of dietary omega-3 polyunsaturated fatty acids (n-3 PUFAs) on glutamatergic system modulation after a single episode of neonatal seizures and their possible effects on seizure-induced long-lasting behavioral deficits. METHODS: Male Wistar rats receiving an omega-3 diet (n-3) or an n-3 deficient diet (D) from the prenatal period were subjected to a kainate-induced seizure model at P7. Glutamate transporter activity and immunocontents (GLT-1 and GLAST) were assessed in the hippocampus at 12, 24, and 48 h after the seizure episode. Fluorescence intensity for glial cells (GFAP) and neurons (NeuN) was assessed 24 h after seizure in the hippocampus. Behavioral analysis (elevated-plus maze and inhibitory avoidance memory task) was performed at 60 days of age. RESULTS: The D group showed a decrease in glutamate uptake 24 h after seizure. In this group only, the GLT1 content increased at 12 h, followed by a decrease at 24 h. GLAST increased up to 24 h after seizure. GFAP fluorescence was higher, and NeuN fluorescence decreased, in the D group independent of seizures. In adulthood, the D group presented memory deficits independent of seizures, but short-term memory (1.5 h after a training session) was abolished in the D group treated with kainate. SIGNIFICANCE: N-3 PUFA positively influenced the glutamatergic system during seizure and prevented seizure-related memory deficits in adulthood.


Assuntos
Epilepsia , Ácidos Graxos Ômega-3 , Animais , Dieta , Ácidos Graxos Ômega-3/efeitos adversos , Feminino , Ácido Glutâmico , Hipocampo , Ácido Caínico , Masculino , Transtornos da Memória/prevenção & controle , Gravidez , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/prevenção & controle
3.
Phytother Res ; 34(6): 1282-1290, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31989713

RESUMO

Obesity is a worldwide epidemic and is one of the factors involved in the etiology of type 2 diabetes mellitus. Obesity induces low-grade inflammation and oxidative stress. The treatment for obesity involves changes in diet, physical activity, and even medication and surgery. Currently, the use of nutraceutical compounds is associated with health benefits. Ginger and avocado are used for many people all around the world; however, its effect as a nutraceutical compound is less known by the general population. For this reason, we searched information of the literature to point its effects on distinct mechanisms of defense against the obesity its comorbidities. The present review aimed showing that these nutraceuticals may be useful in obesity treatment. Reports have shown that ginger and avocado induce antioxidant and anti-inflammatory effects by improving enzymatic activity and modulating obesity-related impairments in the anti-inflammatory system in different tissues, without side effects. Furthermore, ginger and avocado were found to be effective in reversing the harmful effects of obesity on blood lipids. In conclusion, on the basis of the positive effects of ginger and avocado in in vitro, animal, and human studies, these nutraceuticals may be useful in obesity treatment.


Assuntos
Fármacos Antiobesidade/uso terapêutico , Suplementos Nutricionais/análise , Obesidade/tratamento farmacológico , Persea/química , Zingiber officinale/química , Animais , Fármacos Antiobesidade/farmacologia , Humanos
4.
Nutrition ; 54: 158-164, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29982143

RESUMO

OBJECTIVE: The aim of this study was to investigate the regulatory effects of taurine on the biochemical parameters of muscle injury by overuse. METHODS: Male Swiss mice were divided into four groups: control (Ctrl), overuse (Ov), taurine (Tau), and overuse plus taurine (OvTau). High-intensity exercise sessions were administered for 21 d with concomitant subcutaneous injections of taurine (150 mg/kg). The mice were then sacrificed. The quadriceps muscles were surgically removed for subsequent histologic analysis and evaluation of mitochondrial function, oxidative stress parameters, tissue repair, and DNA damage markers. RESULTS: The Ov group showed significant differences compared with the Ctrl group (all P <0.05). The fiber area decreased by 49.34%, whereas the centralized nuclei contents (Ctrl = 1.33%; Ov = 28.67%), membrane potential (Ctrlsuc = 179.05 arbitrary fluorescence units (AFUs), Ctrlsuc+ADP = 198.11 AFUs; Ovsuc = 482.95 AFUs, Ovsuc+ADP = 461.6 AFUs), complex I activity (Ctrl = 20.45 nmol ⋅ min ⋅ mg protein, Ov = 45.25 nmol ⋅ min ⋅ mg protein), hydrogen peroxide (Ctrlsuc = 1.08 relative fluorescence unit (RFU) ⋅ sec ⋅ mg protein, Ctrlsuc+ADP = 0.23 RFU ⋅ sec ⋅ mg protein; Ovsuc = 5.02 RFU ⋅ sec ⋅ mg protein, Ovsuc+ADP = 0.26 RFU ⋅ sec ⋅ mg protein) and malondialdehyde (Ctrl = 0.03 nmol ⋅ mg ⋅ protein, Ov = 0.06 nmol ⋅ mg ⋅ protein) levels, and DNA damage (Ctrlfreq = 7.17%, Ovfreq = 31.17%; Ctrlindex = 4.17, Ovindex = 72.5) were increased. Taurine administration reduced the number of centralized nuclei (OvTau = 5%), hydrogen peroxide levels (OvTausuc = 2.81 RFU ⋅ sec ⋅ mg protein, OvTaussuc+ADP = 1.54 RFU ⋅ sec ⋅ mg protein), membrane potential (OvTausuc = 220.18 AFUs, OvTaussuc+ADP = 235.28 AFUs), lipid peroxidation (OvTau = 0.02 nmol/mg protein), and DNA damage (OvTaufreq = 21.33%, OvTauindex = 47.83) and increased the fiber area by 54% (all P <0.05). CONCLUSION: Taken together, these data suggest that taurine supplementation modulates various cellular remodeling parameters after overuse-induced muscle damage, and that these positive effects may be related to its antioxidant capacity.


Assuntos
Antioxidantes/farmacologia , Transtornos Traumáticos Cumulativos/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Taurina/farmacologia , Animais , Transtornos Traumáticos Cumulativos/fisiopatologia , Modelos Animais de Doenças , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia
5.
Ann Clin Transl Neurol ; 4(6): 392-402, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28589166

RESUMO

OBJECTIVE: Clinical neurological assessment is challenging for severe traumatic brain injury (TBI) patients in the acute setting. Waves of neurochemical abnormalities that follow TBI may serve as fluid biomarkers of neurological status. We assessed the cerebrospinal fluid (CSF) levels of glutamate, lactate, BDNF, and GDNF, to identify potential prognostic biomarkers of neurological outcome. METHODS: This cross-sectional study was carried out in a total of 20 consecutive patients (mean [SD] age, 29 [13] years; M/F, 9:1) with severe TBI Glasgow Coma Scale ≤ 8 and abnormal computed tomography scan on admission. Patients were submitted to ventricular drainage and had CSF collected between 2 and 4 h after hospital admission. Patients were then stratified according to two clinical outcomes: deterioration to brain death (nonsurvival, n = 6) or survival (survival, n = 14), within 3 days after hospital admission. CSF levels of brain-derived substances were compared between nonsurvival and survival groups. Clinical and neurological parameters were also assessed. RESULTS: Glutamate and lactate are significantly increased in nonsurvival relative to survival patients. We tested the accuracy of both biomarkers to discriminate patient outcome. Setting a cutoff of >57.75, glutamate provides 80.0% of sensitivity and 84.62% of specificity (AUC: 0.8214, 95% CL: 54.55-98.08%; and a cutoff of >4.65, lactate has 100% of sensitivity and 85.71% of specificity (AUC: 0.8810, 95% CL: 54.55-98.08%). BDNF and GDNF did not discriminate poor outcome. INTERPRETATION: This early study suggests that glutamate and lactate concentrations at hospital admission accurately predict death within 3 days after severe TBI.

6.
Mol Neurobiol ; 54(8): 5807-5814, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27660270

RESUMO

Hyperpalatable diets (HP) impair brain metabolism, and regular physical exercise has an apparent opposite effect. Here, we combined a prior long-term exposure to HP diet followed by physical exercise and evaluated the impact on some neuroenergetic components and on cognitive performance. We assessed the extracellular lactate concentration, expression of monocarboxylate transporters (MCTs), pyruvate dehydrogenase (PDH), and mitochondrial function in the hippocampus. Male C57BL/6J mice were fed 4 months with HP or a control diet. Subsequently, they were divided in the following groups: control diet sedentary (CDS), control diet exercise (CDE), HP diet sedentary (HPS), and HP diet exercise (HPE) (n = 15 per group) and were engaged for an additional 30-day period of voluntary exercise and HP diet. Relative to the control situation, exercise increased MCT1, MCT4, and PDH protein levels, while the HP diet increased MCT1 and MCT4 protein levels. The production of hydrogen peroxide (H2O2) and the mitochondrial membrane potential (∆Ñ°m) stimulated by succinate in hippocampal homogenates were not significantly different between groups. ADP phosphorylation and the maximal respiratory rate induced by FCCP showed similar responses between groups, implying a normal mitochondrial function. Also, extracellular brain lactate levels were increased in the HPE group compared to other groups soon after performing the Y-maze task. However, such enhanced lactate levels were not associated with improved memory performance. In summary, hippocampal protein expression levels of MCT1 and 4 were increased by physical exercise and HP diet, whereas PDH was only increased by exercise. These observations indicate that a hippocampal metabolic reprogramming takes place in response to these environmental factors.


Assuntos
Dieta , Peróxido de Hidrogênio/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neuroglia/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Masculino , Camundongos Endogâmicos C57BL , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Simportadores/metabolismo
8.
Mol Neurobiol ; 53(9): 5807-5817, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26497034

RESUMO

Aging is a major risk factor for cognitive deficits and neurodegenerative disorders, and impaired brain insulin receptor (IR) signaling is mechanistically linked to these abnormalities. The main goal of this study was to investigate whether brain insulin infusions improve spatial memory in aged and young rats. Aged (24 months) and young (4 months) male Wistar rats were intracerebroventricularly injected with insulin (20 mU) or vehicle for five consecutive days. The animals were then assessed for spatial memory using a Morris water maze. Insulin increased memory performance in young rats, but not in aged rats. Thus, we searched for cellular and molecular mechanisms that might account for this distinct memory response. In contrast with our expectation, insulin treatment increased the proliferative activity in aged rats, but not in young rats, implying that neurogenesis-related effects do not explain the lack of insulin effects on memory in aged rats. Furthermore, the expression levels of the IR and downstream signaling proteins such as GSK3-ß, mTOR, and presynaptic protein synaptophysin were increased in aged rats in response to insulin. Interestingly, insulin treatment increased the expression of the brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) receptors in the hippocampus of young rats, but not of aged rats. Our data therefore indicate that aged rats can have normal IR downstream protein expression but failed to mount a BDNF response after challenge in a spatial memory test. In contrast, young rats showed insulin-mediated TrkB/BDNF response, which paralleled with improved memory performance.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Cognição/efeitos dos fármacos , Insulina/administração & dosagem , Insulina/farmacologia , Fatores de Crescimento Neural/metabolismo , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proliferação de Células/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Injeções Intraventriculares , Masculino , Plasticidade Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Ratos Wistar , Receptor trkB/metabolismo , Transdução de Sinais/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos
9.
Front Cell Neurosci ; 9: 219, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26089779

RESUMO

The role of glutamate N-methyl-D-aspartate receptor (NMDAR) hypofunction has been extensively studied in schizophrenia; however, less is known about its role in anxiety disorders. Recently, it was demonstrated that astrocytic GLT-1 blockade leads to an anxiety-like phenotype. Although astrocytes are capable of modulating NMDAR activity through glutamate uptake transporters, the relationship between astrocytic glutamate uptake and the development of an anxiety phenotype remains poorly explored. Here, we aimed to investigative whether long-term antagonism of NMDAR impacts anxiety-related behaviors and astrocytic glutamate uptake. Memantine, an NMDAR antagonist, was administered daily for 24 days to healthy adult CF-1 mice by oral gavage at doses of 5, 10, or 20 mg/kg. The mice were submitted to a sequential battery of behavioral tests (open field, light-dark box and elevated plus-maze tests). We then evaluated glutamate uptake activity and the immunocontents of glutamate transporters in the frontoparietal cortex and hippocampus. Our results demonstrated that long-term administration of memantine induces anxiety-like behavior in mice in the light-dark box and elevated plus-maze paradigms. Additionally, the administration of memantine decreased glutamate uptake activity in both the frontoparietal cortex and hippocampus without altering the immunocontent of either GLT-1 or GLAST. Remarkably, the memantine-induced reduction in glutamate uptake was correlated with enhancement of an anxiety-like phenotype. In conclusion, long-term NMDAR antagonism with memantine induces anxiety-like behavior that is associated with reduced glutamate uptake activity but that is not dependent on GLT-1 or GLAST protein expression. Our study suggests that NMDAR and glutamate uptake hypofunction may contribute to the development of conditions that fall within the category of anxiety disorders.

10.
Nutr Neurosci ; 17(4): 186-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24621058

RESUMO

Omega-3 (n-3) fatty acids are important for adequate brain function and cognition. The aim of the present study was to evaluate how n-3 fatty acids influence the persistence of long-term memory (LTM) in an aversive memory task and to explore the putative mechanism involved. Female rats received isocaloric diets that included n-3 (n-3 group) or not (D group). The adult litters were subjected to an inhibitory avoidance task (0.7 mA, 1.0 seconds foot shock) to elicit persistent LTM. Twelve hours after the training session, the fatty acid profile and the brain derived neurotrophic factor (BDNF) content of the dorsal hippocampus were assessed. In addition, we measured the activation of the NR2B subunit of the N-methyl-d-aspartate (NMDA) receptor and the SRC family protein Fyn. Despite pronounced learning in both groups, the persistence of LTM was abolished in the D group 7 days after the training session. We also observed that the D group presented reductions in hippocampal DHA (22:6 n-3) and BDNF content. Twelve hours after the training session, the D group showed decreased NR2B and Fyn phosphorylation in the dorsal hippocampus, with no change in the total content of these proteins. Further, there was a decrease in the interaction of Fyn with NR2B in the D group, as observed by co-immunoprecipitation. Taken together, these data suggest that n-3 fatty acids influence the persistence of LTM by maintaining adequate levels of DHA and BDNF as well as by influencing the activation of NR2B and Fyn during the period of memory formation.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Ácidos Graxos Ômega-3/sangue , Memória de Longo Prazo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fyn/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Insaturados/deficiência , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Fosforilação , Ratos , Ratos Wistar
11.
J Alzheimers Dis ; 30(4): 889-98, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22475793

RESUMO

Insulin brain resistant state is associated with cognitive deficits and Alzheimer's disease by mechanisms that may involve mitochondrial damage and oxidative stress. Conversely, physical exercise improves cognitive function and brain insulin signaling. The intracerebroventricular (i.c.v.) administration of streptozotocin (STZ) in rodents is an established model of insulin-resistant brain state. This study evaluates the effects of physical exercise on memory performance of i.c.v., STZ-treated mice(1 and 3 mg/kg) and whether insulin (50 and 100 ng/ml) modulates mitochondrial H2O2 generation in synaptosomes. S100B levels and SOD and CAT activities were assessed as markers of brain damage caused by STZ. Sedentary and exercise vehicle-treated mice demonstrated similar performance in object recognition memory task. In the water maze test, exercise vehicle-treated mice showed improvement performance in the acquisition and retrieval phases. The administration of STZ (1 mg/kg) before thirty days of voluntary physical exercise protocol impaired recognition and spatial memory only in exercised mice, whereas STZ (3 mg/kg) impaired the performance of sedentary and exercise groups. Moreover, STZ (3 mg/kg) increased hippocampal S100B levels in both groups and SOD/CAT ratio in the sedentary animals. Insulin decreased synaptosomal H2O2 production in exercised compared to sedentary mice; however, both STZ doses abolished this effect. Normal brain insulin signaling is mechanistically involved in the improvement of cognitive function induced by exercise through the regulation of mitochondrial H2O2 production. However, a prior blockade of brain insulin signaling with STZ abolished the benefits of exercise on memory performance and mitochondrial H2O2 regulation.


Assuntos
Peróxido de Hidrogênio/metabolismo , Insulina/fisiologia , Transtornos da Memória/metabolismo , Condicionamento Físico Animal/fisiologia , Estreptozocina/toxicidade , Sinaptossomos/metabolismo , Animais , Células Cultivadas , Peróxido de Hidrogênio/antagonistas & inibidores , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/induzido quimicamente , Camundongos , Atividade Motora/fisiologia , Condicionamento Físico Animal/efeitos adversos , Estreptozocina/administração & dosagem , Sinaptossomos/efeitos dos fármacos
12.
Hippocampus ; 21(10): 1082-92, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20824731

RESUMO

Increasing evidence indicates that physical exercise induces adaptations at the cellular, molecular, and systemic levels that positively affect the brain. Insulin plays important functional roles within the brain that are mediated by insulin-receptor (IR) signaling. In the hippocampus, insulin improves synaptic plasticity, memory formation, and learning via direct modulation of GABAergic and glutamatergic receptors. Separately, physical exercise and central insulin administration exert relevant roles in cognitive function. We here use CF1 mice to investigate (i) the effects of voluntary exercise on hippocampal insulin signaling and memory performance and (ii) whether central insulin administration alters the effects of exercise on hippocampal insulin signaling and memory performance. Adult mice performed 30 days of voluntary exercise on running wheel and afterward both, sedentary and exercised groups, received intracerebroventricular (icv) injection of saline or insulin (0.5-5 mU). Memory performance was assessed using the inhibitory avoidance and water maze tasks. Hippocampal tissue was measured for [U-(14)C] glucose oxidation and the immunocontent of insulin receptor/signaling (IR, pTyr, pAktser473). Additionally, the phosphorylation of the glutamate NMDA receptor NR2B subunit and the capacity of glutamate uptake were measured, and immunohistochemistry was used to determine glial reactivity. Exercise significantly increased insulin peripheral sensitivity, spatial learning, and hippocampal IR/pTyrIR/pAktser473 immunocontent. Glucose oxidation, glutamate uptake, and astrocyte number also increased relative to the sedentary group. In both memory tasks, 5 mU icv insulin produced amnesia but only in exercised animals. This amnesia was associated a rapid (15 min) and persistent (24 h) increase in hippocampal pNR2B immunocontent that paralleled the increase in glial reactivity. In conclusion, physical exercise thus increased hippocampal insulin signaling and improved water maze performance. Overstimulation of insulin signaling in exercised animals, however, via icv administration impaired behavioral performance. This effect was likely the result of aberrant phosphorylation of the NR2B subunit.


Assuntos
Hipocampo , Insulina/administração & dosagem , Condicionamento Físico Animal/fisiologia , Receptor de Insulina/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Amnésia/fisiopatologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Cognição/fisiologia , Glucose/metabolismo , Ácido Glutâmico/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Imuno-Histoquímica , Injeções Intraventriculares , Resistência à Insulina/fisiologia , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Memória/efeitos dos fármacos , Memória/fisiologia , Camundongos , Neuroglia/metabolismo , Fosforilação , Transdução de Sinais/fisiologia
13.
Behav Pharmacol ; 21(7): 668-75, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20729714

RESUMO

Olanzapine and highly palatable diets can alter metabolism and brain function. We investigated the interaction of chronic treatment (4 months) with olanzapine and a cafeteria diet on metabolic parameters, memory tasks (spatial and aversive), the elevated plus maze and locomotor activity induced by d-amphetamine. Male Wistar rats were separated into the following groups: standard diet vehicle, standard diet and olanzapine, cafeteria diet vehicle and cafeteria diet and olanzapine. Olanzapine was administered in the drinking water (approximately 1.5 mg/kg/day), and after 3 days of treatment, the rats exhibited an expected anxiolytic effect and reduced amphetamine-induced hyperlocomotion. After 4 months of treatment, cafeteria diet vehicle and cafeteria diet olanzapine rats exhibited an increased body weight and heavier fat pads compared with the standard diet groups. Olanzapine increased only the epididymal and mesenteric fat pads. The cafeteria diet and olanzapine group showed greater glucose intolerance compared with all other groups. The cafeteria diet altered the effects of chronic olanzapine on the performance in the water maze and inhibitory avoidance tasks. Chronic olanzapine treatment failed to affect amphetamine-induced locomotion and to produce anxiolytic effects in the elevated plus maze task, regardless of the diet. Our results suggest that chronic olanzapine caused an increase in fat pads, which is putatively involved in the etiology of many metabolic diseases. Rats on the cafeteria diet were overweight and exhibited glucose intolerance. We did not observe these effects with olanzapine treatment with the standard diet. Moreover, the chronic treatment regimen caused tolerance to the antipsychotic and anxiolytic effects of olanzapine and seemed to potentiate some of the metabolic effects of the cafeteria diet. The cafeteria diet also modified the effects of chronic treatment with olanzapine on cognitive tasks, which may represent an undesirable effect of poor diets in psychiatric patients.


Assuntos
Comportamento Animal , Benzodiazepinas , Fast Foods , Intolerância à Glucose , Obesidade , Anfetamina/farmacologia , Animais , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Comportamento Animal/efeitos dos fármacos , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Dieta/psicologia , Gorduras na Dieta/efeitos adversos , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/psicologia , Fast Foods/efeitos adversos , Intolerância à Glucose/etiologia , Intolerância à Glucose/metabolismo , Humanos , Masculino , Aprendizagem em Labirinto , Atividade Motora/efeitos dos fármacos , Obesidade/etiologia , Obesidade/metabolismo , Olanzapina , Ratos , Ratos Wistar
14.
Exp Biol Med (Maywood) ; 234(12): 1437-44, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19934364

RESUMO

Nutrition during pregnancy and lactation can program an offspring's metabolism with regard to glucose and lipid homeostasis. A suboptimal environment during fetal, neonatal and infant development is associated with impaired glucose tolerance, type 2 diabetes and insulin resistance in later adult life. However, studies on the effects of a low protein diet imposed from the beginning of gestation until adulthood are scarce. This study's objective was to investigate the effects of a low protein diet imposed from the gestational period until 4 months of age on the parameters of glucose tolerance and insulin responsiveness in Wistar rats. The rats were divided into a low protein diet group and a control group and received a diet with either 7% or 25% protein, respectively. After birth, the rats received the same diet as their mothers, until 4 months of age. In the low protein diet group it was observed that: (i) the hepatic glycogen concentration and hepatic glycogen synthesis from glycerol were significantly greater than in the control group; (ii) the disposal of 2-deoxyglucose in soleum skeletal muscle slices was 29.8% higher than in the control group; (iii) there was both a higher glucose tolerance in the glucose tolerance test; and (iv) a higher insulin responsiveness in than in the control group. The results suggest that the low protein diet animals show higher glucose tolerance and insulin responsiveness relative to normally nourished rats. These findings were supported by the higher hepatic glycogen synthesis and the higher disposal of 2-deoxyglucose in soleum skeletal muscle found in the low protein diet rats.


Assuntos
Envelhecimento/metabolismo , Resistência à Insulina , Complicações na Gravidez/metabolismo , Deficiência de Proteína/metabolismo , Animais , Desoxiglucose/metabolismo , Proteínas Alimentares , Feminino , Idade Gestacional , Teste de Tolerância a Glucose , Glicerol/metabolismo , Glicogênio/biossíntese , Lactação/metabolismo , Fígado/metabolismo , Masculino , Músculo Esquelético/metabolismo , Gravidez , Ratos , Ratos Wistar
15.
Mol Nutr Food Res ; 52(11): 1365-71, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18655006

RESUMO

The ketogenic diet (KD), characterized by high fat and low carbohydrate and protein contents, has been proposed to be beneficial in children with epilepsy disorders not helped by conventional anti-epileptic drug treatment. Weight loss and inadequate growth is an important drawback of this diet and metabolic causes are not well characterized. The aim of this study was to examine body weight variation during KD feeding for 6 wk of Wistar rats; fat mass and adipocyte cytosolic phosphoenolpyruvate carboxykinase (PEPCK) activity were also observed. PEPCK activity was determined based on the [H(14)CO(3) (-)]-oxaloacetate exchange reaction. KD-fed rats gained weight at a less rapid rate than normal-fed rats, but with a significant increment in fat mass. The fat mass/body weight ratio already differed between ketogenic and control rats after the first week of treatment, and was 2.4 x higher in ketogenic rats. The visceral lipogenesis was supported by an increment in adipocyte PEPCK, aiming to provide glycerol 3-phosphate to triacylglycerol synthesis and this fat accumulation was accompanied by glucose intolerance. These data contribute to our understanding of the metabolic effects of the KD in adipose tissue and liver and suggest some potential risks of this diet, particularly visceral fat accumulation.


Assuntos
Tecido Adiposo/anatomia & histologia , Dieta Cetogênica/estatística & dados numéricos , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Redução de Peso/fisiologia , Tecido Adiposo/efeitos dos fármacos , Animais , Criança , Colesterol/sangue , Epilepsia/prevenção & controle , Humanos , Masculino , Ratos , Ratos Wistar , Triglicerídeos/sangue , Redução de Peso/efeitos dos fármacos
16.
Exp Biol Med (Maywood) ; 232(8): 1021-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17720948

RESUMO

The aim of this study was to investigate the potential relationship between hypothyroidism and delta-aminolevulinate dehydratase (delta-ALA-D) activity in rat blood and liver. Experimental hypothyroidism was induced in weanling rats by exposing their mothers to propylthiouracil (PTU) diluted in tap water (0.05% w/ v), ad libitum, during the lactational period (PTU group). Control (euthyroid) group included weanling rats whose mothers received just tap water, ad libitum, during the lactational period. Reverted-hypothyroid group (PTU + 3,3',5-triiodo-L-thyronine [T(3)]) included weanling rats whose mothers were exposed to PTU similarly to those in the hypothyroid group, but pups received daily subcutaneous injections of T(3) (20 microg/kg, from Postnatal Days 2-20). After the treatment, serum T(3) levels were drastically decreased (around 70%) in the PTU group, and this phenomenon was almost reverted by exogenous T(3). PTU decreased blood delta-ALA-D activity by 75%, and T(3) treatment prevented such phenomena. Erythrocytes and hemoglobin levels were increased by 10% in PTU-treated animals and higher increments (around 25%) were observed in these parameters when exogenous T(3) was coadministered. Dithiothreitol did not change blood delta-ALA-D activity of PTU-exposed animals when present in the reaction medium, suggesting no involvement of the enzyme's essential thiol groups in PTU-induced delta-ALA-D inhibition. PTU did not affect blood delta-ALA-D activity in vitro. These results are the first to show a correlation between hypothyroidism and decreased delta-ALA-D activity and point to this enzyme as a potential molecule involved with hypothyroidism-related hematological changes.


Assuntos
Hipotireoidismo Congênito/enzimologia , Fígado/enzimologia , Sintase do Porfobilinogênio/sangue , Animais , Animais Recém-Nascidos , Antitireóideos/toxicidade , Hipotireoidismo Congênito/sangue , Hipotireoidismo Congênito/induzido quimicamente , Modelos Animais de Doenças , Ditiotreitol/farmacologia , Ativação Enzimática/efeitos dos fármacos , Eritrócitos/enzimologia , Feminino , Hemoglobinas/análise , Lactação/sangue , Masculino , Ratos , Ratos Wistar , Tiouracila/toxicidade , Tri-Iodotironina/farmacologia
17.
Neurochem Res ; 31(3): 417-22, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16733818

RESUMO

We studied the effect of different concentrations of 2-deoxy-D-glucose on the L-[U-14C]leucine, L-[1-14C]leucine and [1-14C]glycine metabolism in slices of cerebral cortex of 10-day-old rats. 2-deoxy-D-glucose since 0.5 mM concentration has inhibited significantly the protein synthesis from L-[U-14C]leucine and from [1-14C]glycine in relation to the medium containing only Krebs Ringer bicarbonate. Potassium 8.0 mM in incubation medium did not stimulate the protein synthesis compared to the medium containing 2.7 mM, and at 50 mM diminishes more than 2.5 times the protein synthesis compared to the other concentration. Only at the concentration of 5.0 mM, 2-deoxy-D-glucose inhibited the CO2 production and lipid synthesis from L-[U-14C] leucine. This compound did not inhibit either CO2 production, or lipid synthesis from [1-14C]glycine. Lactate at 10 mM and glucose 5.0 mM did not revert the inhibitory effect of 2-deoxy-D-glucose on the protein synthesis from L-[U-14C]leucine. 2-deoxy-D-glucose at 2.0 mM did not show any effect either on CO2 production, or on lipid synthesis from L-[U-14C]lactate 10 mM and glucose 5.0 mM.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Desoxiglucose/farmacologia , Glicina/metabolismo , Leucina/metabolismo , Animais , Dióxido de Carbono/metabolismo , Radioisótopos de Carbono , Córtex Cerebral/metabolismo , Desoxiglucose/metabolismo , Glucose/metabolismo , Técnicas In Vitro , Ácido Láctico/metabolismo , Lipídeos/biossíntese , Fosforilação , Biossíntese de Proteínas/efeitos dos fármacos , Ratos , Ratos Wistar
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