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OBJECTIVE: To evaluate the synergic effects of a novel oral supplement formulation, containing prebiotics, yeast ß-glucans, minerals and silymarin (Silybum marianum), on lipid and glycidic metabolism, inflammatory and mitochondrial proteins of the liver, in control and high-fat diet-induced obese mice. METHODS: After an acclimation period, 32 male C57BL/6 mice were divided into the following groups: nonfat diet (NFD) vehicle, NFD supplemented, high-fat diet (HFD) vehicle and HFD supplemented. The vehicle and experimental formulation were administered orally by gavage once a day during the last four weeks of the diet (28 consecutive days). We then evaluated energy homeostasis, inflammation, and mitochondrial protein expression in these groups of mice. RESULTS: After four weeks of supplementation, study groups experienced reduced glycemia, dyslipidemia, fat, and hepatic fibrosis levels. Additionally, proliferator-activated receptor-α, AMP-activated protein kinase-1α, peroxisome proliferator-activated receptor γ co-activator-1α, and mitochondrial transcription factor A expression levels were augmented; however, levels of inhibitor of nuclear factor-κB kinase subunit α and p65 nuclear factor-κB expression, and oxidative markers were reduced. Notably, the cortisol/C-reactive protein ratio, a well-characterized marker of the hypothalamic-pituitary-adrenal axis immune interface status, was found to be modulated by the supplement. CONCLUSION: We discovered that the novel supplement was able to modify different antioxidant, metabolic and inflammatory pathways, improving the energy homeostasis and inflammatory status, and consequently alleviated hepatic steatosis.

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Intermittent fasting protocol (IFP) has been suggested as a strategy to change body metabolism and improve health. The effects of IFP seem to be similar to aerobic exercise, having a hormetic adaptation according to intensity and frequency. However, the effects of combining both interventions are still unknown. Therefore, the aim of the present study was to evaluate the effects of IFP with and without endurance-exercise training on body composition, food behavior, and lipid metabolism. Twenty-week-old Wistar rats were kept under an inverted circadian cycle of 12 h with water ad libitum and assigned to 4 different groups: control group (ad libitum feeding and sedentary), exercise group (ad libitum feeding and endurance training), intermittent fasting group (IF; intermittent fasting and sedentary), and intermittent fasting and exercise group (IFEX; intermittent fasting and endurance training). After 6 weeks, the body weight of IF and IFEX animals decreased without changes in food consumption. Yet, the body composition between the 2 groups was different, with the IFEX animals containing higher total protein and lower total fat content than the IF animals. The IFEX group also showed increases in total high-density lipoprotein cholesterol and increased intramuscular lipid content. The amount of brown adipose tissue was higher in IF and IFEX groups; however, the IFEX group showed higher expression levels of uncoupling protein 1 in this tissue, indicating a greater thermogenesis. The IFP combined with endurance training is an efficient method for decreasing body mass and altering fat metabolism, without inflicting losses in protein content.

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BACKGROUND: Performing high intensity or exhaustive exercise can lead to muscle damage such as injuries, chronic fatigue and overtraining, partly due to the high synthesis of reactive oxygen species. The α-lipoic acid (ALA) and its reduced form, dihydrolipoic acid, act as potent antioxidant and eliminate free radicals. Although this response depends on the type of exercise and supplementation, animal and human studies have shown the benefits of antioxidant supplementation on the recovery of damages caused by exhaustive exercise, either by restoring antioxidant levels or by decreasing the damage. OBJECTIVE: We evaluated the effect of ALA supplementation on muscular biomarkers of oxidative stress following exhaustive exercise of trained mice. METHODS: Sixty mice were trained to swim for 6 weeks. On the last week, half of the animals were supplemented daily with 100 mg/kg of oral gavage of ALA in soy oil as a vehicle. The other half received just the vehicle. On the last day 20 animals from each group were submitted to an exhaustion protocol with 10% overweight attached to tail. Animals were euthanized on 3 moments: basal, just after the exhaustive protocol (0 h) and, 4 h after the exhaustive protocol. The gastrocnemius muscle was promptly excised and homogenized. The homogenates were used to estimate oxidative stress biomarkers. RESULTS: There was a simultaneous decrease of non-protein thiols and vitamin E after 4 h of exhaustive exercise in the ALA group (p<0.05) compared to the control group, suggesting the consumption of these compounds in the process of lipid peroxidation. Interestingly, there was an increase of nitrate and nitrite in ALA group (p<0.05) and a decrease in the control (p<0.05) compared to basal moment, possibly by activation of endothelial nitric oxide synthase. The total antioxidant capacity remained unchanged in the ALA group. CONCLUSION: The supplementation with ALA resulted in a protection against oxidative stress caused by exhaustive exercise.

CONTEXTO: A realização de exercício de alta intensidade ou exaustivo pode levar a danos musculares, como lesões, fadiga crônica e overtraining, em parte devido à alta síntese de espécies reativas de oxigênio. O ácido α-lipóico e sua forma reduzida, o ácido dihidrolipóico, atuam como potentes antioxidantes e eliminam os radicais livres. Apesar de depender do tipo de exercício e suplementação, estudos com animais e humanos mostram benefícios da suplementação com antioxidante na recuperação de danos causados pelo exercício exaustivo, seja restaurando os níveis de antioxidantes ou diminuindo os danos. OBJETIVO: Avaliar o efeito da suplementação com ácido α-lipóico sobre biomarcadores musculares de estresse oxidativo após o exercício exaustivo de camundongos treinados. METODOLOGIA: Os camundongos (n = 60) foram treinados em natação por 6 semanas. Na última semana, metade dos animais foram suplementados diariamente com gavagem oral de 100 mg / kg de ácido α-lipóico em óleo de soja como veículo. A outra metade recebeu apenas o veículo. No último dia 20 animais de cada grupo foram submetidos ao protocolo de exaustão com 10% de sobrepeso atado à cauda. Os animais foram eutanasiados em 3 momentos: basal, logo após o protocolo de exaustão (0 h) e 4 h após o protocolo de exaustão. O músculo gastrocnêmio foi imediatamente coletado e homogeneizado. Os homogeneizados foram usados para acessar os biomarcadores de estresse oxidativo. RESULTADOS: Houve diminuição simultânea de tióis não protéicos e vitamina E após 4 h de exercício exaustivo no grupo ácido α-lipóico (p <0,05) em relação ao grupo controle, sugerindo o consumo destes compostos no processo de peroxidação lipídica. Interessantemente, houve aumento de nitrato e nitrito no grupo ácido α-lipóico (p <0,05) e diminuição no controle (p <0,05) em relação ao momento basal, possivelmente pela ativação da óxido nítrico sintase endotelial. A capacidade antioxidante total permaneceu inalterada no grupo ácido α-lipóico. CONCLUSÃO: A suplementação com ácido α-lipóico resultou em proteção contra o estresse oxidativo causado pelo exercício exaustivo.

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In this study, we tested the use of murinometric indices and bioimpedance (BIA) to determine obesity in rats. Female Wistar rats (8 weeks/130-160 g) were divided into control and oophorectomy group. The Body Mass Index (BMI) and Lee index (LI) were used as anthropometric techniques to determine obesity, and the determination of body composition by BIA, as a way to partition body weight into fat mass and lean mass components. The dissection of muscle tissues and adipose deposits was used as a direct determination of body fat content. The groups had body weight gain (p <0.05) after the trial period, with a differential gain in body fat (p <0.05) observed by the dissection of tissue in the oophorectomy group. This gain in body fat was detected more accurately by BIA, due to the greater ability of this method to distinguish lean from fat mass. BIA was able to measure the differential gain of body fat in a BMI considered as eutrophic by murinometric indices.

Neste estudo, foi testado o uso de índices murinométricos e da bioimpedância (BIA) na determinação da obesidade em ratos. Ratas Wistar (8 semanas/130-160g) foram divididas em dois grupos: controle e ooforectomia. O Índice de Massa Corporal (IMC) e o índice de Lee (IL) foram utilizados como técnicas antropométricas para a determinação da obesidade e da composição corporal por BIA, como um meio de fracionamento do peso corporal em sua massa de gordura e componentes de massa magra. A dissecação dos tecidos musculares e depósitos adiposos foi utilizada como uma forma direta de determinação do teor de gordura corporal. Os grupos tiveram ganho de peso corporal (p <0,05) após o período experimental, com o grupo ooforectomia com ganho diferencial na gordura corporal (p <0,05), observada na dissecação do tecido adiposo. Esse ganho de gordura corporal foi percebido com maior precisão pela BIA devido à maior capacidade de diferenciação da massa corporal magra e da massa de gordura no peso corporal por meio do método. A BIA foi capaz de perceber o ganho diferencial da fração de gordura corporal em um IMC proposto como eutrófico pelos índices murinométricos.

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RESUMO

In this study, we tested the use of murinometric indices and bioimpedance (BIA) to determine obesity in rats. Female Wistar rats (8 weeks/130-160 g) were divided into control and oophorectomy group. The Body Mass Index (BMI) and Lee index (LI) were used as anthropometric techniques to determine obesity, and the determination of body composition by BIA, as a way to partition body weight into fat mass and lean mass components. The dissection of muscle tissues and adipose deposits was used as a direct determination of body fat content. The groups had body weight gain (p 0.05) after the trial period, with a differential gain in body fat (p 0.05) observed by the dissection of tissue in the oophorectomy group. This gain in body fat was detected more accurately by BIA, due to the greater ability of this method to distinguish lean from fat mass. BIA was able to measure the differential gain of body fat in a BMI considered as eutrophic by murinometric indices.(AU)

Neste estudo, foi testado o uso de índices murinométricos e da bioimpedância (BIA) na determinação da obesidade em ratos. Ratas Wistar (8 semanas/130-160g) foram divididas em dois grupos: controle e ooforectomia. O Índice de Massa Corporal (IMC) e o índice de Lee (IL) foram utilizados como técnicas antropométricas para a determinação da obesidade e da composição corporal por BIA, como um meio de fracionamento do peso corporal em sua massa de gordura e componentes de massa magra. A dissecação dos tecidos musculares e depósitos adiposos foi utilizada como uma forma direta de determinação do teor de gordura corporal. Os grupos tiveram ganho de peso corporal (p 0,05) após o período experimental, com o grupo ooforectomia com ganho diferencial na gordura corporal (p 0,05), observada na dissecação do tecido adiposo. Esse ganho de gordura corporal foi percebido com maior precisão pela BIA devido à maior capacidade de diferenciação da massa corporal magra e da massa de gordura no peso corporal por meio do método. A BIA foi capaz de perceber o ganho diferencial da fração de gordura corporal em um IMC proposto como eutrófico pelos índices murinométricos.(AU)

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