Weekend ethanol consumption and high-sucrose diet: resveratrol effects on energy expenditure, substrate oxidation, lipid profile, oxidative stress and hepatic energy metabolism.

AIMS: The present study analyzed the association between weekend ethanol and high-sucrose diet on oxygen consumption, lipid profile, oxidative stress and hepatic energy metabolism. Because resveratrol (RS, 3,5,4'-trans-trihydroxystilbene) has been implicated as a modulator of alcohol-independent cardiovascular protection attributed to red wine, we also determined whether RS could change the damage done by this lifestyle. METHODS: Male Wistar 24 rats receiving standard chow were divided into four groups (n = 6/group): (C) water throughout the experimental period; (E) 30% ethanol 3 days/week, water 4 days/week; (ES) a mixture of 30% ethanol and 30% sucrose 3 days/week, drinking 30% sucrose 4 days/week; (ESR) 30% ethanol and 30% sucrose containing 6 mg/l RS 3 days/week, drinking 30% sucrose 4 days/week. RESULTS: After 70 days the body weight was highest in ESR rats. E rats had higher energy expenditure (resting metabolic rate), oxygen consumption (VO(2)), fat oxidation, serum triacylglycerol (TG) and very low-density lipoprotein (VLDL) than C. ES rats normalized calorimetric parameters and enhanced carbohydrate oxidation. ESR ameliorated calorimetric parameters, reduced TG, VLDL and lipid hydroperoxide/total antioxidant substances, as well enhanced high-density lipoprotein (HDL) and HDL/TG ratio. Hepatic hydroxyacyl coenzyme-A dehydrogenase (OHADH)/citrate synthase ratio was lower in E and ES rats than in C. OHADH was highest in ESR rats. CONCLUSIONS: The present study brought new insights on weekend alcohol consumption, demonstrating for the first time, that this pattern of ethanol exposure induced dyslipidemic profile, calorimetric and hepatic metabolic changes which resemble that of the alcoholism. No synergistic effects were found with weekend ethanol and high-sucrose intake. RS was advantageous in weekend drinking and high-sucrose intake condition ameliorating hepatic metabolism and improving risk factors for cardiovascular damage.

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 triacylglycerol, 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.

N-acetylcysteine in high-sucrose diet-induced obesity: energy expenditure and metabolic shifting for cardiac health.

To study the effects of N-acetylcysteine (NAC, C(5)H(9)-NO(3)S) on high-sucrose diet-induced obesity and its effects on energy metabolism and cardiac oxidative stress, male Wistar 24 rats were divided into four groups (n=6): (C) given standard chow and water; (N) receiving standard chow and 2g/l N-acetylcysteine in its drinking water; (HS) given standard chow and 30% sucrose in its drinking water, and (HS-N) receiving standard chow, 30% sucrose and N-acetylcysteine in its drinking water. After 30 days of the treatment, obesity was evidenced in HS rats from enhanced body weight, respiratory quotient, hypertriglyceridemia. As well depressed resting metabolic rate, and oxygen consumption per surface area. HS rats had triacylglycerol accumulation, oxidative stress and metabolic shifting in cardiac tissue. NAC enhanced fat oxidation and energy expenditure, normalizing these adverse effects, comparing HS-N and HS rats. The beta-hydroxyacyl coenzymne-A dehydrogenase activity was higher in HS-N animals, indicating higher heart fatty acid degradation than in HS. NAC normalized myocardial glycogen and lactate dehydrogenase activity, comparing HS-N and HS rats, but had no effects on calorimetric and biochemical parameters in standard-fed rats, comparing N and C groups. In conclusion, N-acetylcysteine offers promising therapeutic value in prevention of high-sucrose induced-obesity and its effect on cardiac tissue. N-acetylcysteine reduced the oxidative stress and prevented the metabolic shifting in cardiac tissue, enhancing fatty acid oxidation and reducing anaerobic metabolism in high-sucrose-fed conditions. The application of this agent in food system via exogenous addition may be feasible and beneficial for antioxidant protection and energy metabolism in cardiac tissue.

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

Alcoholism has been associated with a wide range of pathologic conditions, including alcoholic heart disease (AHD). Because AHD may be associated with oxidative stress, antioxidant compounds, such as N-acetylcysteine (NAC) could be useful to control the damage done by alcohol (ethanol) consumption. To investigate the NAC effects on alcoholism and alcohol abstinence, initially, 30 male Wistar 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 2g/L NAC; (AB) changed ethanol solution to water; (AB-NAC) changed ethanol to aqueous solution of 2g/L NAC. After 15 days of the E-group division, E-E rats had lower body weight and feed efficiency, as well as higher energy-expenditure resting metabolic rate (RMR)/body weight and VO(2) consumption/surface area. These calorimetric changes were reflected on the cardiac tissue. E-E rats had higher heart weight/body weight ratio and myocardial lipid hydroperoxide (LH), indicating AHD with hypertrophy and oxidative stress. Myocardial superoxide dismutase was higher, whereas glutathione-peroxidase (GSH-peroxidase) was lower in E-E rats than in C. The higher myocardial hydroxyacyl coenzyme-A dehydrogenase (OHADH), OHADH/citrate synthase (CS), and lactate dehydrogenase (LDH)/CS in E-E rats indicated higher fatty acid degradation relative to aerobic metabolism predisposing the lipotoxicity. AB rats had lower RMR/body weight than E-E, normalized myocardial oxidative stress, and energy metabolism. E-NAC and AB-NAC had lower RMR/body weight, myocardial LH, LDH/CS, and higher GSH-peroxidase than E-E and AB, respectively, demonstrating lower oxidative stress and higher myocardial carbohydrate oxidation. In conclusion, the present study brought new insights on alcohol consumption and AHD because ethanol-exposure enhanced energy-expenditure and induced a number of calorimetric changes, which were reflected in body weight and myocardial lipotoxicity. NAC preventing ethanol-induced calorimetric changes and reducing myocardial oxidative stress enhanced carbohydrate oxidation, thus optimizing myocardial energy metabolism in both alcoholic and abstinence condition.