Resistance Exercise Training Improves Metabolic and Inflammatory Control in Adipose and Muscle Tissues in Mice Fed a High-Fat Diet.

This study investigates whether ladder climbing (LC), as a model of resistance exercise, can reverse whole-body and skeletal muscle deleterious metabolic and inflammatory effects of high-fat (HF) diet-induced obesity in mice. To accomplish this, Swiss mice were fed for 17 weeks either standard chow (SC) or an HF diet and then randomly assigned to remain sedentary or to undergo 8 weeks of LC training with progressive increases in resistance weight. Prior to beginning the exercise intervention, HF-fed animals displayed a 47% increase in body weight (BW) and impaired ability to clear blood glucose during an insulin tolerance test (ITT) when compared to SC animals. However, 8 weeks of LC significantly reduced BW, adipocyte size, as well as glycemia under fasting and during the ITT in HF-fed rats. LC also increased the phosphorylation of AktSer473 and AMPKThr172 and reduced tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL1-ß) contents in the quadriceps muscles of HF-fed mice. Additionally, LC reduced the gene expression of inflammatory markers and attenuated HF-diet-induced NADPH oxidase subunit gp91phox in skeletal muscles. LC training was effective in reducing adiposity and the content of inflammatory mediators in skeletal muscle and improved whole-body glycemic control in mice fed an HF diet.

Modulatory effects of taurine on metabolic and oxidative stress parameters in a mice model of muscle overuse.

OBJECTIVE: The aim of this study was to investigate the regulatory effects of taurine on the biochemical parameters of muscle injury by overuse. METHODS: Male Swiss mice were divided into four groups: control (Ctrl), overuse (Ov), taurine (Tau), and overuse plus taurine (OvTau). High-intensity exercise sessions were administered for 21 d with concomitant subcutaneous injections of taurine (150 mg/kg). The mice were then sacrificed. The quadriceps muscles were surgically removed for subsequent histologic analysis and evaluation of mitochondrial function, oxidative stress parameters, tissue repair, and DNA damage markers. RESULTS: The Ov group showed significant differences compared with the Ctrl group (all P <0.05). The fiber area decreased by 49.34%, whereas the centralized nuclei contents (Ctrl = 1.33%; Ov = 28.67%), membrane potential (Ctrlsuc = 179.05 arbitrary fluorescence units (AFUs), Ctrlsuc+ADP = 198.11 AFUs; Ovsuc = 482.95 AFUs, Ovsuc+ADP = 461.6 AFUs), complex I activity (Ctrl = 20.45 nmol ⋅ min ⋅ mg protein, Ov = 45.25 nmol ⋅ min ⋅ mg protein), hydrogen peroxide (Ctrlsuc = 1.08 relative fluorescence unit (RFU) ⋅ sec ⋅ mg protein, Ctrlsuc+ADP = 0.23 RFU ⋅ sec ⋅ mg protein; Ovsuc = 5.02 RFU ⋅ sec ⋅ mg protein, Ovsuc+ADP = 0.26 RFU ⋅ sec ⋅ mg protein) and malondialdehyde (Ctrl = 0.03 nmol ⋅ mg ⋅ protein, Ov = 0.06 nmol ⋅ mg ⋅ protein) levels, and DNA damage (Ctrlfreq = 7.17%, Ovfreq = 31.17%; Ctrlindex = 4.17, Ovindex = 72.5) were increased. Taurine administration reduced the number of centralized nuclei (OvTau = 5%), hydrogen peroxide levels (OvTausuc = 2.81 RFU ⋅ sec ⋅ mg protein, OvTaussuc+ADP = 1.54 RFU ⋅ sec ⋅ mg protein), membrane potential (OvTausuc = 220.18 AFUs, OvTaussuc+ADP = 235.28 AFUs), lipid peroxidation (OvTau = 0.02 nmol/mg protein), and DNA damage (OvTaufreq = 21.33%, OvTauindex = 47.83) and increased the fiber area by 54% (all P <0.05). CONCLUSION: Taken together, these data suggest that taurine supplementation modulates various cellular remodeling parameters after overuse-induced muscle damage, and that these positive effects may be related to its antioxidant capacity.

The Effects of Physical Training are Varied and Occur in an Exercise Type-Dependent Manner in Elderly Men.

Regular exercise can decrease the deleterious effects of aging and limit the development and progression of chronic disease in elderly people, depending on the type, intensity, frequency, and duration of exercise. This study aimed to investigate the potential protective effects of different physical training programs on oxidative stress parameters and inflammatory and neurotrophic mediators in the serum of elderly men. Healthy male volunteers [60 to 80 years; n=55] were divided into four groups: control [Ctr, n=14], aerobic training on dry land [ATdl, n=12]; and combined training on dry land [CTdl, n=12] or in water [CTw, n=17]. The training protocols were performed over 8 weeks, three times per week. Each 1 h session included 5 min warming-up exercise, 50 min specific training [aerobic, strength, or combined], and 5 min stretching. Blood samples were drawn 72 h before [baseline] the beginning of the 8 weeks' protocol and 48 h after the last training session, processed, and the serum was aliquoted and stored at -70 °C until biochemical assessment of oxidative damage, antioxidant system and neurotrophic, growth and inflammatory factors. Elevated BDNF or IGF-1 levels were observed in the ATdl or CTdl groups, respectively. Overall oxidative stress parameters were improved including reduced lipid oxidative damage and increased thioredoxin reductase and glutathione peroxidase activities and total glutathione. Significant decreases in the inflammatory mediators IL-6 and IL-8 were observed; IL-6 was more susceptible to the effects of type of physical training. Thus, the effects of training in elderly men vary in an exercise type-dependent manner.

Gold nanoparticles and/or N-acetylcysteine mediate carrageenan-induced inflammation and oxidative stress in a concentration-dependent manner.

We report the effect of gold nanoparticles (AuNP) in an acute inflammation model induced by carrageenan (CG) and compared this effect with those induced by the antioxidant N-acetylcysteine (NAC) alone and by the synergistic effect of NAC and AuNP together. Male Wistar rats received saline or saline containing CG administered into the pleural cavity, and some rats also received NAC (20 mg/kg) subcutaneously and/or AuNP administered into the pleural cavity immediately after surgery. Four hours later, the rats were sacrificed and pleural exudates obtained for evaluation of cytokine levels and myeloperoxidase activities. Oxidative stress parameters were also evaluated in the lungs. The results demonstrated that the inflammatory process caused by the administration of CG into the pleural cavity resulted in a substantial increase in the levels of tumor necrosis factor-α, interleukin-1ß, and myeloperoxidase and a reduction in interleukin-10 levels. These levels seem to be reversed after different treatments in animals. Antioxidant enzymes exhibited positive responses after treatment of NAC + AuNP, and all treatments were effective at reducing lipid peroxidation and oxidation of thiol groups induced by CG. These findings suggest that small compounds, such as NAC plus AuNP, may be useful in the treatment of conditions associated with local inflammation.

A diferença de idade é um fator determinante na modulação do estresse oxidativo muscular induzido pelo exercício agudo

Resumo Este estudo teve por objetivo comparar os efeitos do exercício agudo com carga de trabalho relativa em gastrocnêmio de ratos Wistar com três e 18 meses. Os animais foram divididos em quatro grupos (n = 6): controle de três e 18 meses; exercício de três e 18 meses. Os grupos exercitados foram submetidos a uma única sessão de corrida na esteira com 60 minutos em velocidade de 0,8 km/h e 1,2 km/h. Foram analisados parâmetros do metabolismo (níveis de lactato, conteúdo de glicogênio, níveis de succinato desidrogenase, citocromo c oxidase e de estresse oxidativo (SOD, CAT e GPX). Os resultados mostraram um aumento nos marcadores metabólicos após o exercício agudo independentemente da idade dos animais e similaridade nos danos oxidativos apesar de as enzimas antioxidantes apresentarem modulação diferenciada nos animais mais velhos em comparação com animais jovens.

Abstract The effects of exercise on the generation of reactive oxygen species and the response to muscle oxidative stress determines longevity. This study compares the effects of acute exercise with similar relative workload in rats with 3 and 18 months. The animals were divided into four groups (n = 6): control 3-months; exercise 3-months; control 18-months and exercise 18-months. Exercised groups underwent to a single bout of running with 60 minutes in the speed 0.8 km/h (18 months) and 1.2 km/h (3 months). Metabolic parameters (lactate levels, glycogen content, succinate dehydrogenase levels, cytochrome c oxidase) and oxidative stress (activity of superoxide dismutase, catalase and glutathione peroxidase). The results showed an increase in metabolic markers after acute exercise regardless of the age and similarity in oxidative damage even if the antioxidant enzymes are age-dependent. These results suggest that the effects of acute exercise at moderate intensity, affects the metabolism independent of age, and, that the differential response in enzymatic antioxidant system between groups do not promote protection against oxidative damage.

Este estudio ha tenido como objetivo comparar los efectos del ejercicio agudo con carga de trabajo relativamente similar en el gastrocnemio de ratas Wistar con 3 y 8 meses. Se separó a los animales en cuatro grupos (n = 6): control de 3 y 18 meses, y ejercicio de 3 y 18 meses. Se sometió a los grupos de ejercicio a una sola sesión de carrera en la cinta durante 60 minutos con una velocidad de 0,8 km/h y 1,2 km/h. Se analizaron algunos parámetros del metabolismo (niveles de lactato, contenido de glucógeno, niveles de succionato-deshidrogenasa, citocromo c-oxidasa e de estrés oxidativo [superóxido-dismutasa, catalasa y glutatión-peroxidasa]). Los resultados mostraron un aumento de los marcadores metabólicos después del ejercicio agudo independientemente de la edad de los animales y la similitud de los daños oxidativos aunque las enzimas antioxidantes presentan modulación diferenciada en animales viejos en comparación con animales jóvenes.