Garyfallia Kapravelou

Improvement of the antioxidant and hypolipidaemic effects of cowpea flours (Vigna unguiculata) by fermentation: results of in vitro and in vivo experiments

BACKGROUND The antioxidant capacity and hypolipidaemic effects of Vigna unguiculata, as well as their potential improvement by different fermentation and thermal processes were studied using in vitro and in vivo methods. RESULTS Phenolic content and reducing capacity of legume acetone extract were significantly increased by different fermentation processes, and by the thermal treatment of fermented legume flours. TBARS inhibiting capacity was increased by fermentation but not by thermal treatment. A higher ability to decrease Cu(2+)/H2O2-induced electrophoretic mobility of LDL was found in fermented when compared to raw legume extracts, and a higher protective effect on short term metabolic status of HT-29 cells was found for raw and lactobacillus-fermented Vigna followed by naturally fermented Vigna extracts. Significant improvements in plasma antioxidant capacity and hepatic activity of antioxidant enzymes were observed in rats that consumed fermented legume flours when compared to the untreated legume or a casein-methionine control diet. In addition, liver weight and plasma levels of cholesterol and triglycerides were also positively affected by untreated or naturally fermented Vigna. CONCLUSION V. unguiculata has demonstrated its potential as a functional food with interesting antioxidant and lipid lowering properties, which can be further augmented by fermentation processes associated or not to thermal processing.

Effects of the dietary amount and source of protein, resistance training and anabolic-androgenic steroids on body weight and lipid profile of rats

INTRODUCTION Dietary protein amount and source, hypertrophy resistance training (RT) and anabolicandrogenic steroids (AAS) may affect body weight and plasma and hepatic lipid profile. MATERIAL AND METHODS 157 adult male Wistar rats were randomly distributed in 16 experimental groups resulting in: normal-protein (NP) or high-protein (HP) diets, whey or soy-protein diets, with or without RT and with or without AAS, for 3 months. RESULTS AND DISCUSSION Final body weight was lower in the RT and AAS groups compared to sedentary and non- AAS groups, respectively (all, p<0.001). Plasma total cholesterol (TC) was lower for the HP compared to the NP diets, for the whey compared to the soy-protein diets and for the AAS compared to the non-AAS groups (all, p<0.001). Plasma HDL-cholesterol was higher in the RT groups (p<0.05) but lower for the AAS groups (p<0.001), the HP and the soy-protein diets (p<0.05). Plasma triglycerides (TAG) were lower for the HP diet (p<0.001), for the RT (p=0.002) and the non-AAS groups (p=0.001). Liver TC was lower for the NP (p<0.01), for the soyprotein (p<0.05) and for the AAS groups (p<0.001). Liver TAG were lower for the whey-protein diet (p<0.001), RT and non-AAS groups (both, p<0.05). Some interactions were found, such as the greater effect of AAS on reducing body weight of rats that performed RT or ingested a HP diet (all, p<0.05). HDL-cholesterol was higher when RT was combined with HP diets (p=0.010) or non-AAS and when HP diets were combined with non-AAS (both,p<0.001). Groups that combined RT with non-AAS administration obtained the lowest hepatic TAG (p<0.05). CONCLUSION Among all the interventions tested, AAS was the factor that most negatively affected plasma and hepatic lipid profile, whereas HP diets and RT could benefit lipid profile, especially when combined.

Aerobic interval exercise improves parameters of nonalcoholic fatty liver disease (NAFLD) and other alterations of metabolic syndrome in obese Zucker rats

Metabolic syndrome (MS) is a group of metabolic alterations that increase the susceptibility to cardiovascular disease and type 2 diabetes. Nonalcoholic fatty liver disease has been described as the liver manifestation of MS. We aimed to test the beneficial effects of an aerobic interval training (AIT) protocol on different biochemical, microscopic, and functional liver alterations related to the MS in the experimental model of obese Zucker rat. Two groups of lean and obese animals (6 weeks old) followed a protocol of AIT (4 min at 65%-80% of maximal oxygen uptake, followed by 3 min at 50%-65% of maximal oxygen uptake for 45-60 min, 5 days/week, 8 weeks of experimental period), whereas 2 control groups remained sedentary. Obese rats had higher food intake and body weight (P < 0.0001) and suffered significant alterations in plasma lipid profile, area under the curve after oral glucose overload (P < 0.0001), liver histology and functionality, and antioxidant status. The AIT protocol reduced the severity of alterations related to glucose and lipid metabolism and increased the liver protein expression of PPARγ, as well as the gene expression of glutathione peroxidase 4 (P < 0.001). The training protocol also showed significant effects on the activity of hepatic antioxidant enzymes, although this action was greatly influenced by rat phenotype. The present data suggest that AIT protocol is a feasible strategy to improve some of the plasma and liver alterations featured by the MS.

High-protein diet induces oxidative stress in rat brain: protective action of high-intensity exercise against lipid peroxidation

INTRODUCTION It is well established that soy protein diets as well as aerobic exercise could promote antioxidant capacity and consequently reduce free radicals overproduction on brain. However, little is know regarding to the high-protein diets and high intensity exercise on oxidative stress production. The aim of this study was to analyse the effects of high-protein diets and high-intensity exercise (HIE) on brain oxidative stress markers. MATERIALS AND METHODS A total of 40 male Wistar rats were randomly distributed in 4 experimental groups (n=10): normal-protein or high-protein diets with or without HIE for an experimental period of 12 weeks. Main oxidative damage markers in brain such as thiobarbituric acid-reactive substances (TBARs) and protein carbonyl content (PCC) were assessed. In addition, brain manganese superoxide dismutase (Mn-SOD), cooper/ zinc superoxide dismutase (CuZn-SOD) and catalase (CAT) antioxidant enzymes activity, and protein level of Nuclear factor erythroid 2 related factor 2 (Nrf2) were measured. RESULTS AND DISCUSSION Brain TBARs, PCC, tSOD, Mn-SOD, CuZn-SOD and CAT levels were higher in the high-protein compared to the normal-protein groups (all, p.

Effects of interval aerobic training combined with strength exercise on body composition, glycaemic and lipid profile and aerobic capacity of obese rats

ABSTRACT The purpose of this study was to investigate the effects of interval aerobic training combined with strength exercise in the same training session on body composition, and glycaemic and lipid profile in obese rats. Sixteen lean Zucker rats and sixteen obese Zucker rats were randomly divided into exercise and sedentary subgroups (4 groups, n = 8). Exercise consisted of interval aerobic training combined with strength exercise in the same training session. The animals trained 60 min/day, 5 days/week for 8 weeks. Body composition, lipid and glycaemic profiles and inflammatory markers were assessed. Results showed that fat mass was reduced in both lean and obese rats following the exercise training (effect size (95% confidence interval (CI)) = 1.8 (0.5–3.0)). Plasma low-density lipoprotein–cholesterol and fasting glucose were lower in the exercise compared to the sedentary groups (d = 2.0 (0.7–3.2) and 1.8 (0.5–3.0), respectively). Plasma insulin was reduced in exercise compared to sedentary groups (d = 2.1 (0.8–3.4)). Some exercise × phenotype interactions showed that the highest decreases in insulin, homeostatic model assessment-insulin resistance, fasting and postprandial glucose were observed in the obese + exercise group (all, P < 0.01). The findings of this study suggest that interval aerobic training combined with strength exercise would improve body composition, and lipid and glycaemic profiles, especially in obese rats.

Resistance training reduces the metabolic acidosis and hepatic and renal hypertrophy caused by the consumption of a high protein diet in rats

INTRODUCTION High protein (HP) diet consumption may adversely affect metabolic acidosis and hepatic and renal health. Despite such potentially adverse effect, there are only few studies analyzing the effects of resistance training on the parameters that could be altered by such diets. MATERIAL AND METHODS A total of 32 adult male Wistar rats were randomly distributed in 4 experimental groups (n = 8): normoprotein or HP diets, with or without resistance training. Diets were based on a whey protein hydrolyzate, and the experimental period lasted for 90 days. RESULTS AND DISCUSSION Consumption of HP diets and resistance training significantly affected food intake, body composition and plasmatic levels of total cholesterol and triglycerides. Consumption of HP diets led to a considerable increase in liver and kidney weight (P < 0.001), urinary volume and acidity, as well as in the urinary excretion of Ca, with a parallel reduction in the urinary excretion of citrate (P < 0.05). The buffering action of resistance training on such diet-induced alterations was especially evident in the levels of hepatic and plasma triglycerides, plasmatic urea, and in liver and kidney weight (P < 0.001). CONCLUSION Resistance training had a protective action against alterations of hepatic and renal health status and some metabolic parameters like hepatic and plasma triglycerides.

High-intensity Exercise Modifies the Effects of Stanozolol on Brain Oxidative Stress in Rats.

We analyzed the effects of high-intensity exercise (HIE) and anabolic androgenic steroids (AAS) on brain redox status. 40 male Wistar rats were randomly distributed in 4 experimental groups (n=10) with or without HIE and with or without weekly Stanozolol administration. Thiobarbituric acid-reactive substances (TBARs) and protein carbonyl content (PCC) were assessed. Total superoxide dismutase (tSOD), manganese superoxide dismutase (Mn-SOD), copper/zinc superoxide dismutase (CuZn-SOD) and catalase (CAT) activities were measured. Finally, protein expression levels of glutathione peroxidase (GPx), NAD(P)H dehydrogenase, Quinone 1 (NQO1), NF-E2-Related Factor 2 (Nrf2), glial fibrillary acidic protein (GFAP), nuclear factor kappa β p65 (NF-κβ) and signal transducer and activator of transcription 3 were determined. Brain PCC concentrations were lower in the HIE groups compared to the untrained controls, whereas CAT activity was higher (both, p<0.01). Both HIE and AAS groups exhibited higher expression levels of GFAP and GPx, but lower NQO1 levels (all, p<0.05). There were increased expression levels of NF-κβ in the AAS groups (p<0.01). In addition, there was increased expression of Nrf2 in the HIE groups (p<0.001). HIE*AAS interactions were found on TBARs content and GFAP expression, with HIE downregulating and upregulating AAS-mediated increases in TBARs and GFAP, respectively (p<0.05). Overall, HIE appeared to reduce the AAS-mediated negative effect on brain redox status.

The Combined Intervention with Germinated Vigna radiata and Aerobic Interval Training Protocol Is an Effective Strategy for the Treatment of Non-Alcoholic Fatty Liver Disease (NAFLD) and Other Alterations Related to the Metabolic Syndrome in Zucker Rats

Metabolic syndrome (MetS) is a group of related metabolic alterations that increase the risk of developing non-alcoholic fatty liver disease (NAFLD). Several lifestyle interventions based on dietary treatment with functional ingredients and physical activity are being studied as alternative or reinforcement treatments to the pharmacological ones actually in use. In the present experiment, the combined treatment with mung bean (Vigna radiata), a widely used legume with promising nutritional and health benefits that was included in the experimental diet as raw or 4 day-germinated seed flour, and aerobic interval training protocol (65–85% VO2 max) has been tested in lean and obese Zucker rats following a 2 × 2 × 2 (2 phenotypes, 2 dietary interventions, 2 lifestyles) factorial ANOVA (Analysis of Variance) statistical analysis. Germination of V. radiata over a period of four days originated a significant protein hydrolysis leading to the appearance of low molecular weight peptides. The combination of 4 day-germinated V. radiata and aerobic interval training was more efficient compared to raw V. radiata at improving the aerobic capacity and physical performance, hepatic histology and functionality, and plasma lipid parameters as well as reverting the insulin resistance characteristic of the obese Zucker rat model. In conclusion, the joint intervention with legume sprouts and aerobic interval training protocol is an efficient treatment to improve the alterations of glucose and lipid metabolism as well as hepatic histology and functionality related to the development of NAFLD and the MetS.

Effects of a moderately high-protein diet and interval aerobic training combined with strength-endurance exercise on markers of bone metabolism, microarchitecture and turnover in obese Zucker rats

BACKGROUND Weight loss is a public health concern in obesity-related diseases such as metabolic syndrome, and the protein level of the diets seem to be crucial for the development and maintenance of bone. The nature of exercise and whether exercise in combination with moderately high-protein dietary interventions could protect against potential bone mass deficits remains unclear. OBJECTIVES To investigate the effects of a moderately high-protein diet and interval aerobic training combined with strength-endurance exercise (IASE) protocol on bone status, and to assess potential interaction effects (i.e. diet*IASE). METHODS Male Zucker fatty rats were randomized distributed into 4 groups (n=8): normoprotein+sedentary; normoprotein+exercise; moderately high-protein+sedentary, and moderately high-protein+exercise. Training groups conducted an IASE program, 5days/week for 2months. Markers of bone metabolism were measured in plasma. Parameters of bone mass and 3D outcomes for trabecular and cortical bone microarchitecture were assessed by micro-computed tomography. RESULTS Femur length, plasma osteocalcin, sclerostin, osteoprotegerin, receptor activator of nuclear factor kappa-B ligand, insulin, leptin, PTH, uric acid and urinary phosphorus levels were lower in the moderately high-protein compared to the normoprotein groups (all, p<0.05), whereas plasma alkaline phosphatase, aspartate aminotransferase, alanine transaminase, and urinary uric acid concentrations, and cortical total volume (TV) and bone volume (BV) were higher in the moderately high-protein (all, p<0.01). Final body weight and alkaline phosphatase levels were lower in the exercise compared to the sedentary (both, p<0.05), whereas femur length and weight, aminoterminal propeptides of type I procollagen and C-terminal telopeptides of type I collagen concentrations, and cortical TV and BV were higher in the exercise compared to the sedentary groups (all, p<0.05). CONCLUSION The combination of interventions may be effective to enhance trabecular bone microarchitecture and BMD, and has a partial impact on cortical bone in obese rats. Nevertheless, they do not induce any alteration on the bone turnover markers.