Tobacco Smoke Induces Ventricular Remodeling Associated with an Increase in NADPH Oxidase Activity

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Ventricular Remodeling Induced by Tissue Vitamin A Deficiency in Rats

Background/Aims: Experimental studies suggest that vitamin A plays a role in regulating cardiac structure and function. We tested the hypothesis that cardiac vitamin A deficiency is associated with adverse myocardial remodeling in young adult rats. Methods: Two groups of young female rats, control (C - n = 29) and tissue vitamin A deficient (RVA - n = 31), were subjected to transthoracic echocardiography exam, isolated rat heart study and biochemical study. Results: The RVA rats showed a reduced total vitamin A concentration in both the liver and heart [vitamin A in heart, mu mol/kg (C = 0.95 +/- 0.44 and RVA = 0.24 +/- 0.16, p = 0.01)] with the same serum retinol levels (C = 0.73 +/- 0.29 mu mol/L e RVA = 0.62 +/- 0.17 mu mol/L, p = 0.34). The RVA rats showed higher left ventricular diameters and reduced systolic function. The RVA rats also demonstrated increased lipid hydroperoxide/total antioxidant capacity ratio and cardiac levels of IFN-gamma and TNF-alpha but not of metalloproteinase (MMP)-2 and -9 activity. on the other hand, the RVA rats had decreased levels of beta-hydroxyacylcoenzyme A dehydrogenase and lactate dehydrogenase. Conclusions: Tissue vitamin A deficiency stimulated cardiac remodeling and ventricular dysfunction. Additionally, the data support the involvement of oxidative stress, energy metabolism, and cytokine production in this remodeling process. Copyright (C) 2010 S. Karger AG, Basel

Beneficial effects of dietary copper supplementation on serum lipids and antioxidant defenses in rats

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 mu g 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. Copyright (C) 2005 S. Karger AG, Basel.

Effects of N-acetylcysteine on alcohol abstinence and alcohol-induced adverse effects in rats

Alcoholism is rampant in modern society and some antioxidant compound could perhaps be useful to reduce the damage done by alcohol consumption and abstinence. The present study was undertaken to investigate the association of N-acetylcysteine (NAC) intake, alcoholism, and alcohol abstinence on lipid profile, in vivo low-density lipoprotein (LDL) oxidation, oxidative stress, and antioxidant status in serum and liver of rats. Initially, male Wistar 30 rats were divided into two groups: (C, N = 6) given standard chow and water; (E, N = 24) receiving standard chow and aqueous ethanol solution in semi-voluntary research. After 30 days of ethanol exposure, (E) group was divided into four subgroups (N = 6/group): (E-E) continued drinking 30% ethanol solution; (E-NAC) drinking ethanol solution containing 2 g/L NAC (AB) changed ethanol solution to water; (AB-NAC) changed ethanol to aqueous solution 2 g/L NAC. After 15 days of the E-group division, E-E rats had higher serum alanine transaminase, lower body weight, and surface area, despite higher energy intake than C. E-E rats had also lower feed efficiency, dyslipidemia with enhanced triacyl glycerol, very low-density lipoprotein (VLDL), lipid hydroperoxide (LH) and in vivo oxidized-LDL (ox-LDL). AB, E-NAC, and AB-NAC rats ameliorated serum oxidative stress markers and normalized serum lipids. E-E rats had higher hepatic LH and lower reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio than C, indicating hepatic oxidative stress. AB and E-NAC rats normalized hepatic LH, GSSG, and the GSH/GSSG ratio, compared to E-E. AB-NAC rats had the lowest serum ox-LDL, hepatic LH levels, and the highest GSH reductase activity in hepatic tissue. In conclusion, the present study brought new insights into alcohol consumption, because ethanol exposure enhanced serum in vivo ox-LDL, as well as serum and hepatic oxidative stress. N-acetylcysteine offers promising therapeutic value to inhibit ethanol-induced adverse effects. Ethanol withdrawal had beneficial effects on serum lipids, but was more effective when coupled with NAC supplementation. Ethanol abstinence and NAC intake interact synergistically, improving serum lipids and hepatic antioxidant defenses. (c) 2009 Elsevier B.V. All rights reserved.

Alcoholism and alcohol abstinence: N-acetylcysteine to improve energy expenditure, myocardial oxidative stress, and energy metabolism in alcoholic heart disease

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N-Acetylcysteine an Allium Plant Compound Improves High-Sucrose Diet-Induced Obesity and Related Effects

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Antioxidant effect of saponin: potential action of a soybean flavonoid on glucose tolerance and risk factors for atherosclerosis

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.

Effects of digitonin on hyperglycaemia and dyslipidemia induced by high-sucrose intake

This study examined whether high-sucrose intake effects on lipid profile and oral glucose tolerance may be inhibited by a single administration of digitonin, a saponin from the seeds of Digitalis purpurea Male Wistar 24 rats were initially divided into two groups (n = 12): (C) was given standard chow and water; (S) received standard chow and 30% sucrose in its drinking water. After 30 days of treatments, C rats were divided into two groups (n = 6): (CC) given an intra-gastric dose 0.5 mL saline, (CD) given a single intragastric dose of 15 mg/kg digitonin. S rats were also divided into two groups (n = 6): (SC) given intra-gastric saline and (SD) given digitonin. Rats were sacrificed after the oral glucose tolerance test (OGTT) at 2 h after the digitonin administration. S rats had higher total energy intake and final body weight than C. SC rats had fasting hyperglycaemia and impaired OGTT. Digitonin in SD group improved the glucose tolerance. Triacylglycerol (TG), very-low-density lipoprotein (VLDL-C) and free fatty acid (FFA) serum concentrations were increased in SD rats from CC. Digitonin in SD rats decreased FFA and led TG and VLDL-C concentrations at the levels observed in the CC group. Despite the enhanced cholesterol in CD group from CC., the high-density lipoprotein (HDL-C) was increased in these animals. HDL-C/TG ratio was higher in CD and SD than in CC and SC, respectively. No significant differences were observed in lipid hydroperoxide(LH) between the groups. VLDL-C/LH ratio and gamma-glutamyl transferase (GGT) activity were increased in SC group and were decreased in SD rats from the SC. In conclusion digitonin enhanced glucose tolerance and had beneficial effects on serum lipids by improve antioxidant activity. (c) 2005 Elsevier Ltd. All rights reserved.

Diets rich in saturated and polyunsaturated fatty acids: Metabolic shifting and cardiac health

OBJECTIVE: the aim of this study was to determine the effects of diets rich in saturated and polyunsaturated fatty acids on metabolic pathways and the relation of metabolic shifting to oxidative stress in cardiac tissue.METHODS: Male Wistar rats (age, 60 d; n = 10) were fed with a control low-fat diet, a diet rich in saturated fatty acids (SFAs), or a diet rich in polyunsaturated fatty acids (PUFAs). After 5 wk of treatment, sera were used for protein and lipid determinations. Protein, glycogen, triacylglycerol, lactate dehydrogenase, citrate synthase, beta-hydroxyacyl coenzyme-A dehydrogenase, catalase, glutathione peroxidase, superoxide dismutase, lipoperoxide, and lipid hydroperoxide were measured in cardiac tissue.RESULTS: the SFA group had higher triacylglycerol, cholesterol, low-density lipoprotein cholesterol, and atherogenic index (ratio of cholesterol to high-density lipoprotein) than did the PUFA and control groups. The PUFA group had low serum cholesterol, triacylglycerol, and low-density lipoprotein cholesterol as compared with the SFA group. SFA increased myocardial lipid hydroperoxide and diminished glutathione peroxidase. Despite the beneficial effects on serum lipids, the PUFA diet led to the highest levels of myocardial lipoperoxide and lipid hydroperoxide and diminished superoxide dismutase and catalase activities. The PUFA effects were related to increased feed efficiency, increased susceptibility to lipoperoxidation, and metabolic shifting in cardiac tissue. PUFA elevated triacylglycerol levels and decreased myocardial glycogen concentrations. The ratios of lactate dehydrogenase to citrate synthase and beta-hydroxyacyl coenzyme-A dehydrogenase to citrate synthase were increased, indicating myocardial reduction of tricarboxylic acid cycle.CONCLUSIONS: PUFAs have been recommended as a therapeutic measure in preventive medicine to lower serum cholesterol, but PUFAs increased oxidative stress in the heart by providing cardiac susceptibility to lipoperoxidation and shifting the metabolic pathway for energy production. The control diet, which was much lower in calories and fat, produced better overall clinical outcomes, better fat profiles, and less oxidative stress than did the diets rich in fatty acids.

Anthropometrical parameters and markers of obesity in rats

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 (HQ 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.

Calorimetry, Morphometry, Oxidative Stress, and Cardiac Metabolic Response to Growth Hormone Treatment in Obese and Aged Rats

This study investigated the effects of growth hormone therapy on energy expenditure, lipid profile, oxidative stress and cardiac energy metabolism in aging and obesity conditions. Life expectancy is increasing in world population and with it, the incidence of public health problems such as obesity and cardiac alterations. Because growth hormone (GH) concentration is referred to be decreased in aging conditions, a question must be addressed: what is the effect of GH on aging related adverse changes? To investigate the effects of GH on cardiac energy metabolism and its association with calorimetric parameters, lipid profile and oxidative stress in aged and obese rats, initially 32 male Wistar rats were divided into 2 groups (n = 16), C: given standard-chow and water; H: given hypercaloric-chow and receiving 30 % sucrose in its drinking water. After 45 days, both C and H groups were divided into 2 subgroups (n = 8), C + PL: standard-chow, water, and receiving saline subcutaneously; C + GH: standard-chow, water, and receiving 2 mg/kg/day rhGH subcutaneously; H + PL: hypercaloric-chow, 30 % sucrose, receiving saline subcutaneously; H + GH: hypercaloric-chow, 30 % sucrose, receiving rhGH subcutaneously. After 30 days, C + GH and H + PL rats had higher body mass index, Lee-index, body fat content, percent-adiposity, serum triacylglycerol, cardiac lipid-hydroperoxide, and triacylglycerol than C + PL. Energy-expenditure (RMR)/body weight, oxygen consumption and fat-oxidation were higher in H + GH than in H + PL. LDL-cholesterol was highest in H + GH rats, whereas cardiac pyruvate-dehydrogenase and phosphofrutokinase were higher in H + GH and H + PL rats than in C + PL. In conclusion, the present study brought new insights on aging and obesity, demonstrating for the first time that GH therapy was harmful in aged and obesity conditions, impairing calorimetric parameters and lipid profile. GH was disadvantageous in control old rats, having undesirable effects on triacylglycerol accumulation and cardiac oxidative stress.

Energy Expenditure and Oxygen Consumption as Novel Biomarkers of Obesity-induced Cardiac Disease in Rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resveratrol toxicity: Effects on risk factors for atherosclerosis and hepatic oxidative stress in standard and high-fat diets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Conjugated linoleic acid and cardiac health: Oxidative stress and energetic metabolism in standard and sucrose-rich diets

Studies on conjugated linoleic acid ingestion and its effect on cardiac tissue are necessary for the safe utilization of this compound as supplement for weight loss. Male Wistar 24-rats were divided into four groups (n = 6):(C)given standard chow, water and 0.5 ml saline, twice a week by gavage; (C-CLA)receiving standard chow, water and 0.5 ml of conjugated linoleic acid, twice a week, by gavage; (S)given standard chow, saline by gavage, and 30% sucrose in its drinking water; (S-CLA)receiving standard chow, 30% sucrose in its drinking water and conjugated linoleic acid. After 42 days of treatment S rats had obesity with increased abdominal-circumference, dyslipidemia, oxidative stress and myocardial lower citrate synthase(CS) and higher lactate dehydrogenase(LDH) activities than C. Conjugated linoleic acid had no effects on morphometric parameters in C-CLA, as compared to C, but normalized morphometric parameters comparing S-CLA with S. There was a negative correlation between abdominal adiposity and resting metabolic rate. Conjugated linoleic acid effect, enhancing fasting-VO2/surface area, postprandial-carbohydrate oxidation and serum lipid hydroperoxide resembled to that of the S group. Conjugated linoleic acid induced cardiac oxidative stress in both fed conditions, and triacylglycerol accumulation in S-CLA rats. Conjugated linoleic acid depressed myocardial LDH comparing C-CLA with C, and beta-hydroxyacyl-coenzyme-A dehydrogenase/CS ratio, comparing S-CLA with S. In conclusion, dietary conjugated linoleic acid supplementation for weight loss can have long-term effects on cardiac health. Conjugated linoleic acid, isomers c9, t11 and t10, c12 presented undesirable pro-oxidant effect and induced metabolic changes in cardiac tissue. Nevertheless, despite its effect on abdominal adiposity in sucrose-rich diet condition, conjugated linoleic acid may be disadvantageous because it can lead to oxidative stress and dyslipidemic profile. (c) 2007 Elsevier B.V All rights reserved.

Effects of olive oil and its minor phenolic constituents on obesity-induced cardiac metabolic changes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)