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Aims: The present study investigated the potential effects of pterostilbene (PT) on glycemic and lipid profiles, fat storage, cardiovascular indices, and hepatic parameters of rats fed with sucrose solution., Main Methods: 24 male Wistar rats received either drinking water or a 40% sucrose solution over a period of 140 days. After this period, animals were randomly allocated into four groups (n = 6): Control (C), C + Pterostilbene (PT), Sucrose (S), and S + PT. Pterostilbene (40 mg/kg) was given orally for 45 consecutive days., Key Findings: Pterostilbene did not influence morphometric and nutritional parameters. The insulin sensitivity index TyG was elevated in the C + PT group (p < 0.01) and reduced in S + PT group (p < 0.05). Basal glucose levels were lower in the S + PT group (p < 0.05), and the glycemic response was improved with PT treatment in glucose provocative tests. Conversely, rats from the C + PT group showed impaired glucose disposal during those tests. Lipid profile was partially improved by PT treatment. Hepatic oxidative stress in the S group was improved after PT treatment. In the C group, PT reduced SOD activity, glutathione levels, and increased catalase activity. Collagen content was reduced by PT treatment., Significance: PT effects depends on the type of diet the animals were submitted. In rats fed with sucrose-solution, PT confirmed its positive effects, improving glucose and lipid profile, and acting as a potent antioxidant. The effects of PT on rats that consumed a normal diet were very discrete or even undesirable. We suggest caution with indiscriminate consume of natural compounds by healthy subjects., (Copyright © 2021 Elsevier Inc. All rights reserved.)

As the number of overweight and obese people has risen in recent years, there has been a parallel increase in the number of people with metabolic syndrome, diabetes and non-alcoholic fatty liver disease. The consumption of artificially sweetened beverages contributes to these epidemics. This study investigated the long-term effects of ingestion of a 40% sucrose solution on serum and hepatic parameters in male Wistar rats ( Rattus norvegicus ). After 180 days, the glycemic response, lipid profile and hepatic oxidative stress were compared to those of rats maintained on water. Sucrose ingestion led to higher body weight, increased fat deposits, reduced voluntary food intake and reduced feeding efficiency. Rats that received sucrose solution showed early signs of glucose intolerance and insulin resistance, such as hyperinsulinemia. Serum triacylglycerol (TG), very-low density lipoprotein (VLDL), cholesterol, ALT and AST levels increased after sucrose consumption. Elevated malondialdehyde and superoxide dismutase (SOD) levels and reduced glutathione levels characterize the hepatic oxidative stress due to sucrose ingestion. Liver sample histology showed vacuolar traces and increased fibrotic tissue. Our data showed the harmful effects of chronic consumption of sucrose solution, which can cause alterations that are found frequently in obesity, glucose intolerance and non-alcoholic hepatic disease, characteristics of metabolic syndrome., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

Resveratrol (RSV), polyphenol from grape, was studied to evaluate its effects on calorimetric parameters, energy metabolism, and antioxidants in the myocardium of diabetic rats. The animals were randomly divided into four groups (n = 8): C (control group): normal rats; C-RSV: normal rats receiving RSV; DM: diabetic rats; and DM-RSV: diabetics rats receiving RSV. Type 1 diabetes mellitus was induced with administration of streptozotocin (STZ; 60 mg(-1) body weight, single dose, i.p.). After 48 hours of STZ administration, the animals received RSV (1.0 mg/kg/day) for gavage for 30 days. Food, water, and energy intake were higher in the DM group, while administration of RSV caused decreases (p<0.05) in these parameters. The glycemia decreased and higher final body weight increased in DM-RSV when compared with the DM group. The diabetic rats showed higher serum-free fatty acid, which was normalized with RSV. Oxygen consumption (VO2) and carbon dioxide production (VCO2) decreased (p<0.05) in the DM group. This was accompanied by reductions in RQ. The C-RSV group showed higher VO2 and VCO2 values. Pyruvate dehydrogenase activity was lower in the DM group and normalizes with RSV. The DM group exhibited higher myocardial β-hydroxyacyl coenzyme-A dehydrogenase and citrate synthase activity, and RSV decreased the activity of these enzymes. The DM group had higher cardiac lactate dehydrogenase compared to the DM-RSV group. Myocardial protein carbonyl was increased in the DM group. RSV increased reduced glutathione in the cardiac tissue of diabetic animals. The glutathione reductase activity was higher in the DM-RSV group compared to the DM group. In conclusion, diabetes is accompanied by cardiac energy metabolism dysfunction and change in the biomarkers of oxidative stress. The cardioprotective effect may be mediated through RVS's ability to normalize free fatty acid oxidation, enhance utilization glucose, and control the biomarkers' level of oxidative stress under diabetic conditions.

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.

Carcinogenesis is driven by complex molecular events, often involving key enzymes that regulate oxidative stress (OS). While classical enzymes such as SOD, catalase, and GPx have been extensively studied, other, non-classical oxidative stress-related enzymes (OSRE) may play critical roles in cancer progression. We aimed to explore the role of OSRE involved in an OS scenario and to assess their potential contribution to carcinogenesis in some of the most prevalent cancer types. Through data mining and bioinformatic analysis of gene and protein expression and mutation data, we identified OSRE with altered expression and mutations across cancer types. Functional pathways involving EGFR, MT-ND, GST, PLCG2, PRDX6, SRC, and JAK2 were investigated. Our findings reveal that enzymes traditionally considered peripheral to OS play significant roles in tumor progression. Those OSRE may contribute to cancer initiation and progression, as well as be involved with cancer hallmarks, such as EMT and invasion, proliferation, and ROS production. In addition, enzymes like SRC and JAK2 were found to have dual roles in both promoting ROS generation and being modulated by OS. OSRE also interact with key oncogenic signaling pathways, including Wnt/β-catenin and JAK2/STAT3, linking them to cancer aggressiveness and therapeutic resistance. Future research should focus on translating these findings into clinical applications, including the development of novel inhibitors or drugs targeting these non-classical enzymes. [ABSTRACT FROM AUTHOR]

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 (VO2), 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. [ABSTRACT FROM PUBLISHER]

Abstract: To study the effects of N-acetylcysteine (NAC, C5H9–NO3S) 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. [Copyright &y& Elsevier]