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1.
Lab Anim ; 41(1): 111-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17234057

RESUMO

The present study was undertaken to determine anthropometrical parameters in male adult Wistar rats. We tested the hypothesis that the anthropometrical index may identify obesity and may predict its adverse effects on lipid profile and oxidative stress in rats. Two experimental protocols were performed. In the first experiment, 50 male Wistar rats, 21 days old and fed a control chow were studied up to 150 days of age. In the second experiment, male Wistar rats, 60 days old, were divided into three groups (n = 8): control (C) given free access to a control chow; (S) receiving the control chow and drinking 30% sucrose ad libitum and (HC) fed a high-carbohydrate diet ad libitum. The first experiment showed that food consumption, energy intake and body weight increased with increasing age, while specific rate of body mass gain was significantly decreased. There were no significant differences in body length and thoracic circumference of rats from 60 days of age. The abdominal circumference (AC) and body mass index (BMI) significantly increased with enhancing age in rats up to 90 days of age and remained constant thereafter. In the second experiment, after 30 days of dietary treatment, the final body weight, body mass gain, carcass fat and BMI were higher in S and HC rats than in C. There were no significant alterations in body length and carcass protein among the groups. Triacylglycerol (TG), total cholesterol (CT), low-density lipoprotein cholesterol (LDL-C) and lipid hydroperoxide (LH) were higher in S and HC rats than in C. High-density lipoprotein cholesterol (HDL-C) decreased in HC rats and total antioxidant substances (TAS) decreased in S and HC rats. There were positive correlations between BMI with carcass fat, BMI with LH and BMI and serum TG concentration. In conclusion, the BMI for male adult Wistar rats ranged between 0.45 and 0.68 g/cm(2). Obesity may be easily estimated from the BMI in rats. Alterations in BMI were associated with dyslipidemic profile and oxidative stress in serum of rats and BMI may predict these adverse consequences of the obesity in rats.


Assuntos
Índice de Massa Corporal , Obesidade/veterinária , Ratos Wistar/anatomia & histologia , Doenças dos Roedores/diagnóstico , Fatores Etários , Animais , Biomarcadores/análise , Peso Corporal , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Ingestão de Energia , Metabolismo Energético , Comportamento Alimentar , Metabolismo dos Lipídeos , Masculino , Obesidade/diagnóstico , Obesidade/metabolismo , Ratos , Ratos Wistar/metabolismo , Ratos Wistar/fisiologia , Doenças dos Roedores/metabolismo , Aumento de Peso
2.
Braz J Med Biol Res ; 39(2): 305-12, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16470320

RESUMO

Diets rich in saturated fatty acids are one of the most important causes of atherosclerosis in men, and have been replaced with diets rich in unsaturated fatty acids (UFA) for the prevention of this disorder. However, the effect of UFA on myocardial performance, metabolism and morphology has not been completely characterized. The objective of the present investigation was to evaluate the effects of a UFA-rich diet on cardiac muscle function, oxidative stress, and morphology. Sixty-day-old male Wistar rats were fed a control (N = 8) or a UFA-rich diet (N = 8) for 60 days. Myocardial performance was studied in isolated papillary muscle by isometric and isotonic contractions under basal conditions after calcium chloride (5.2 mM) and ss-adrenergic stimulation with 1.0 microM isoproterenol. Fragments of the left ventricle free wall were used to study oxidative stress and were analyzed by light microscopy, and the myocardial ultrastructure was examined in left ventricle papillary muscle. After 60 days the UFA-rich diet did not change myocardial function. However, it caused high lipid hydroperoxide (176 +/- 5 vs 158 +/- 5, P < 0.0005) and low catalase (7 +/- 1 vs 9 +/- 1, P < 0.005) and superoxide-dismutase (18 +/- 2 vs 27 +/- 5, P < 0.005) levels, and discrete morphological changes in UFA-rich diet hearts such as lipid deposits and mitochondrial membrane alterations compared to control rats. These data show that a UFA-rich diet caused myocardial oxidative stress and mild structural alterations, but did not change mechanical function.


Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Insaturados/administração & dosagem , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Ácidos Graxos Insaturados/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Lipídeos/sangue , Masculino , Microscopia Eletrônica , Contração Miocárdica/fisiologia , Miocárdio/química , Miocárdio/patologia , Tamanho do Órgão , Ratos , Ratos Wistar
3.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(2): 305-312, Feb. 2006.
Artigo em Inglês | LILACS | ID: lil-420284

RESUMO

Diets rich in saturated fatty acids are one of the most important causes of atherosclerosis in men, and have been replaced with diets rich in unsaturated fatty acids (UFA) for the prevention of this disorder. However, the effect of UFA on myocardial performance, metabolism and morphology has not been completely characterized. The objective of the present investigation was to evaluate the effects of a UFA-rich diet on cardiac muscle function, oxidative stress, and morphology. Sixty-day-old male Wistar rats were fed a control (N = 8) or a UFA-rich diet (N = 8) for 60 days. Myocardial performance was studied in isolated papillary muscle by isometric and isotonic contractions under basal conditions after calcium chloride (5.2 mM) and ß-adrenergic stimulation with 1.0 æM isoproterenol. Fragments of the left ventricle free wall were used to study oxidative stress and were analyzed by light microscopy, and the myocardial ultrastructure was examined in left ventricle papillary muscle. After 60 days the UFA-rich diet did not change myocardial function. However, it caused high lipid hydroperoxide (176 ± 5 vs 158 ± 5, P < 0.0005) and low catalase (7 ± 1 vs 9 ± 1, P < 0.005) and superoxide-dismutase (18 ± 2 vs 27 ± 5, P < 0.005) levels, and discrete morphological changes in UFA-rich diet hearts such as lipid deposits and mitochondrial membrane alterations compared to control rats. These data show that a UFA-rich diet caused myocardial oxidative stress and mild structural alterations, but did not change mechanical function.


Assuntos
Animais , Masculino , Ratos , Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Insaturados/administração & dosagem , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácidos Graxos Insaturados/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Lipídeos/sangue , Microscopia Eletrônica , Contração Miocárdica/fisiologia , Miocárdio/química , Miocárdio/patologia , Tamanho do Órgão , Ratos Wistar
4.
Exp Toxicol Pathol ; 57(3): 221-6, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16338125

RESUMO

Recent lines of evidences indicate that several pathological conditions, as cardiovascular diseases, are associated with oxidative stress. In order to validate a butylated hydroxytoluene (BHT)-induced experimental model of oxidative stress in the cardiac tissue and serum lipids, 12 Wistar rats were divided into two groups, a control group and the BHT group, which received BHT i.p. twice a week (1500 mg/kg body weight) during 30 days. BHT group presented lower body weight gain and heart weight. BHT induced toxic effects on serum through increased triacylglycerols (TG), VLDL and LDL-cholesterol concentrations. The heart of BHT animals showed alteration of antioxidant defenses and increased concentrations of lipid hydroperoxides, indicating elevated lipoperoxidation. TG concentrations and lactate dehydrogenase activities were elevated in the cardiac muscle of BHT animals. Thus, long-term administration of BHT is capable to induce oxidative and metabolic alterations similarly to some pathological disorders, constituting an efficient experimental model to health scientific research.


Assuntos
Antioxidantes/toxicidade , Hidroxitolueno Butilado/toxicidade , Lipídeos/sangue , Estresse Oxidativo , Animais , Peso Corporal , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Metabolismo Energético , Peroxidação de Lipídeos , Masculino , Miocárdio , Ratos , Ratos Wistar , Aumento de Peso
5.
Ann Nutr Metab ; 49(5): 283-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16088091

RESUMO

BACKGROUND: A nutrition experiment was utilized to investigate the effects of two levels of dietary copper (Cu) supplementation on lipid profile and antioxidant defenses in serum of rats. METHODS: Male Wistar rats (180-200 g; n = 10) were divided into three groups: control group (A), fed a basal diet with 6 microg Cu/g, and rats fed a basal diet with Cu (CuSO4) supplementation from aqueous solutions, for 4 weeks at the final concentrations of 2 mg Cu/rat (B) and 3 mg Cu/rat (C). RESULTS: No significant changes were observed in final body weight, body weight gain, food consumption, total serum protein and high-density lipoprotein. Cu supplementation reduced the triacylglycerol (TG), total cholesterol and low-density lipoprotein (LDL-C). The LDL-C/TG ratio and total antioxidant substances (TAS) were higher in (B) and (C) groups than in (A) group. There was a positive correlation between Cu supplementation and ceruloplasmin levels. The markers of oxidative stress, lipid hydroperoxide and lipoperoxide were decreased with Cu supplementation. No alterations were observed in superoxide dismutase, indicating saturation of Cu enzyme site. The glutathione peroxidase activities (GSH-Px) were increased in both Cu-supplemented groups. Considering that a copper-selenium interaction can affect mineral availability of both elements, the effects of Cu on TAS and GSH-Px activities were associated with increased selenium disposal. CONCLUSIONS: Dietary Cu supplementation had beneficial effects on lipid profile by improving endogenous antioxidant defenses and decreasing the oxidative stress in vivo.


Assuntos
Antioxidantes/metabolismo , Cobre/administração & dosagem , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Animais , Peso Corporal/efeitos dos fármacos , Ceruloplasmina/metabolismo , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Hipercolesterolemia/prevenção & controle , Peróxidos Lipídicos/sangue , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Triglicerídeos/sangue
6.
Int J Food Sci Nutr ; 56(2): 79-85, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16019317

RESUMO

At the present time, much attention is being paid to antioxidant substances because many pathological conditions are associated with oxidative stress. The purpose of the present study was to discover the potency of saponin (2-phenyl-benzopyrane), a soybean flavonoid, with respect to its hypoglycaemic and hypolipidaemic action, and the association of these effects with oxidative stress. Male Wistar rats were divided into two groups (n = 6): control group and saponin-treated group (60 mg/kg) during 30 days. Saponin had no effects on glucose tolerance. Although no changes had been observed in low-density lipoprotein-cholesterol, saponin-treated animals had increased low-density lipoprotein-cholesterol/triacylglycerol ratio and decreased triacylglycerol, very low-density lipoprotein-cholesterol and total/high-density lipoprotein-cholesterol ratio than the control group. Saponin-treated rats showed lower lipid hydroperoxide than control rats, indicating decreased potential to atherosclerosis. No alterations were observed in antioxidant enzymes, superoxide dismutase and glutathione peroxidase, while lipid hydroperoxide were decreased in saponin-treated rats. In conclusion, the beneficial effects of saponin on serum lipids were related to a direct saponin antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Glucose/metabolismo , Glycine max/química , Saponinas/farmacologia , Animais , Arteriosclerose/etiologia , Biomarcadores/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Peróxidos Lipídicos/sangue , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Fatores de Risco , Triglicerídeos/sangue
7.
Int J Food Sci Nutr ; 54(3): 241-6, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12775373

RESUMO

The purpose of the present study was to discover the relative potency of onion, Allium cepa, with respect to its hypoglycaemic and hypolipidaemic effects on the diabetic situation, and the association of these effects with the potential against oxidative stress. Male Wistar rats were divided into four groups. A normal control (group A), and a non-diabetic group (group B) were treated daily with 1 ml A. cepa solution (0.4 g A. cepa/rat). Groups C and D were made diabetic by an intraperitoneal injection of streptozotocin (STZ) (60 mg/kg body weight) in citrate buffer (pH 6.3). These animals (groups C and D) were the STZ diabetic control and STZ diabetic rats with onion intake, respectively. Onion increased the fasting serum high-density lipoprotein levels, and demonstrated alleviation of hyperglycaemia in STZ diabetic rats. The hypoglycaemic and hypolipidaemic actions of A. cepa were associated with antioxidant activity, since onion decreased superoxide dismutase activities while no increased lipid hydroperoxide and lipoperoxide concentrations were observed in diabetic rats treated with A. cepa.


Assuntos
Antioxidantes/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Cebolas , Fitoterapia , Alanina Transaminase/sangue , Animais , Proteínas Sanguíneas/análise , Colesterol/sangue , HDL-Colesterol/sangue , Diabetes Mellitus Experimental/sangue , Glutationa Peroxidase/sangue , Lipídeos/sangue , Masculino , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Superóxido Dismutase/sangue
8.
Food Chem Toxicol ; 40(12): 1893-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12419704

RESUMO

The present study examines the effects of caloric restriction in cardiac tissue evaluation markers of oxidative stress. High-fat dietary restrictions can have a long-term impact on cardiac health. Dietary restriction of control diet increased myocardial superoxide dismutase (SOD) and catalase activities. Dietary restriction of fatty acid-enriched diets increased myocardial lipoperoxide concentrations, while SOD activity was decreased in cardiac tissue of rats with dietary restriction of fatty acid-enriched diets. Dietary restriction of unsaturated fatty acid-enriched diet induced the highest lipoperoxide concentration and the lowest myocardial SOD activity. Dietary restriction of unsaturated fatty acid decreased myocardial glycogen, and increased the lactate dehydrogenase/citrate synthase ratio. Dietary restriction of fatty acid-enriched diets were more deleterious to cardiac tissue than normal ad lib.-fed diet. In conclusion, the effects of caloric restriction on myocardial oxidative stress is dependent on which nutrient is restricted. Dietary restriction of fatty acid-enriched diets is deleterious relative to ad lib.-fed chow diet.


Assuntos
Catalase/metabolismo , Dieta com Restrição de Gorduras , Gorduras na Dieta/administração & dosagem , Miocárdio/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Animais , Biomarcadores , Dieta com Restrição de Gorduras/efeitos adversos , Dieta Redutora/efeitos adversos , Gorduras na Dieta/efeitos adversos , Gorduras Insaturadas na Dieta/administração & dosagem , Gorduras Insaturadas na Dieta/efeitos adversos , Ingestão de Energia , Masculino , Miocárdio/patologia , Ratos , Ratos Wistar
9.
Food Chem Toxicol ; 40(5): 663-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11955672

RESUMO

The aim of the present study was to determine the effects of ad lib. overfeeding and of dietary restriction (DR) on oxidative stress in cardiac tissue. Lipoperoxide concentrations were decreased and antioxidant enzymes were increased in moderate-DR-fed rats. Severe-DR induced increased lipoperoxide concentrations. Overfeeding increased lipoperoxide levels in cardiac tissue. Total superoxide dismutase (SOD) and Cu-Zn superoxide dismutase (Cu-Zn SOD) activities were decreased in cardiac tissue at 35 days of overfeeding. As no changes in glutathione peroxidase (GSH-Px) were observed in overfed rats, while SOD and Cu-Zn SOD activities were decreased in these animals, it is assumed that superoxide anion is an important intermediate in the toxicity of ad lib. overfeeding. Overfeeding induced alterations in markers of oxidative stress in cardiac tissue.


Assuntos
Hiperfagia/patologia , Miocárdio/patologia , Animais , Biomarcadores , Peso Corporal/fisiologia , Dieta , Ingestão de Alimentos , Ingestão de Energia/fisiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Tamanho do Órgão/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Aumento de Peso/fisiologia
10.
Environ Int ; 27(8): 673-9, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11934117

RESUMO

Water contaminants have a high potential risk for the health of populations. Protection from toxic effects of environmental water pollutants primarily involves considering the mechanism of low level toxicity and likely biological effects in organisms who live in these polluted waters. The biomarkers assessment of oxidative stress and metabolic alterations to cadmium exposure were evaluated in Nile tilapia, Oreochromis niloticus. The fish were exposed to 0.35, 0.75, 1.5, and 3.0 mg/l concentrations of Cd2+ (CdCl2) in water for 60 days. Fish that survived cadmium exposure showed a metabolic shift and a compensatory development for maintenance of the body weight gain. We observed a decreased glycogen content and decreased glucose uptake in white muscle. Lactate dehydrogenase (LDH) and creatine phosphokinase (CK) activities were also decreased, indicating that the glycolytic capacity was decreased in this tissue. No alterations were observed in total protein content in white muscle due to cadmium exposure suggesting a metabolic shift of carbohydrate metabolism to maintenance of the muscle protein reserve. There was an increase in glucose uptake, CK increased activity, and a clear increase of LDH activity in red muscle of fish with cadmium exposure. Since no alterations were observed in lipoperoxide concentration, while antioxidant enzymes glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were changed in the liver and the red and white muscle of fish with cadmium exposure, we can conclude that oxygen free radicals are produced as a mediator of cadmium toxicity. Resistance development is related with increased activities of antioxidant enzymes, which were important in the protection against cadmium damage, inhibiting lipoperoxide formation.


Assuntos
Biomarcadores/análise , Cádmio/efeitos adversos , Estresse Oxidativo , Tilápia/fisiologia , Poluentes da Água/efeitos adversos , Animais , Relação Dose-Resposta a Droga , Exposição Ambiental , Glucose/metabolismo , Glutationa Peroxidase/análise , Glicogênio/análise , Humanos , Saúde Pública , Medição de Risco
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