Exercise Reduces the Resumption of Tumor Growth and Proteolytic Pathways in the Skeletal Muscle of Mice Following Chemotherapy

The pathogenesis of muscle atrophy plays a central role in cancer cachexia, and chemotherapy contributes to this condition. Therefore, the present study aimed to evaluate the effects of endurance exercise on time-dependent muscle atrophy caused by doxorubicin. For this, C57 BL/6 mice were subcutaneously inoculated with Lewis lung carcinoma cells (LLC group). One week after the tumor establishment, a group of these animals initiated the doxorubicin chemotherapy alone (LLC + DOX group) or combined with endurance exercise (LLC + DOX + EXER group). One group of animals was euthanized after the chemotherapy cycle, whereas the remaining animals were euthanized one week after the last administration of doxorubicin. The practice of exercise combined with chemotherapy showed beneficial effects such as a decrease in tumor growth rate after chemotherapy interruption and amelioration of premature death due to doxorubicin toxicity. Moreover, the protein degradation levels in mice undergoing exercise returned to basal levels after chemotherapy; in contrast, the mice treated with doxorubicin alone experienced an increase in the mRNA expression levels of the proteolytic pathways in gastrocnemius muscle (Trim63, Fbxo32, Myostatin, FoxO). Collectively, our results suggest that endurance exercise could be utilized during and after chemotherapy for mitigating muscle atrophy promoted by doxorubicin and avoid the resumption of tumor growth

Efeitos do treinamento concorrente sobre parâmetros da síndrome metabólica em adolescentes obesos

Introdução: A obesidade, por si só, é um fator de risco independente para o desenvolvimento de diversas doenças, e uma das que mais tem motivado investigações científicas é a Síndrome Metabólica (SM), caracterizada pelo agrupamento de, pelo menos, três componentes que caracterizam fatores de risco de origem cardiovascular, cuja prevalência em crianças e adolescentes é elevada. Uma das alternativas para o tratamento está no exercício físico e/ou reeducação alimentar. Objetivo: O objetivo do presente estudo foi avaliar os efeitos da intervenção de 20 semanas por meio do treinamento concorrente (aeróbio e resistido), na composição corporal e sobre a prevalência e os componentes da Síndrome Metabólica em adolescentes obesos. Metodologia: A amostra foi composta por 50 adolescentes obesos com idade entre 12 a 16 anos (13,4±1,1) classificados por meio do Índice de Massa Corporal. Para a análise da composição corporal foi empregada a técnica da absorptiometria de raios-X de dupla energia, verificando-se variáveis como percentual de gordura corporal (%GC), percentual de gordura de tronco (%GTronco) e massa corporal magra (MCM) . Foram avaliados também o colesterol total (COLtotal), HDL-colesterol (HDL), triglicérides (TRI), glicemia em jejum (GLI) e insulina plasmática. A intervenção consistia em treinamento concorrente com 50% do tempo voltado a exercícios aeróbios e a outra metade a exercícios resistidos, com sessões de 60 minutos, 3 vezes/semana, durante 20 semanas. Análise estatística: foram calculadas a mediana e intervalo interquartílico de todas as variáveis...Introduction: Obesity, by itself, is an independent risk factor for the development of various diseases, one that has motivated even more scientific research is the metabolic syndrome (MS), characterized by the clustering of at least three components that characterize risk factors of cardiovascular origin, whose prevalence in children and adolescents is high. An alternative to this treatment is diet and/or exercise. Objective: The objective of this study was to evaluate the effects of 20 weeks intervention of concurrent training (aerobic and resistance), on body composition and on the prevalence and the components of metabolic syndrome in obese adolescents. Methodology: The sample consisted of 50 obese adolescents aged 12-16 years (13.4±1.1) classified by Body Mass Index. For body composition analysis was employed the technique of Dual energy X-ray absorptiometry, in order to verify variables such as body fat percentage (%BF), percentage of trunk fat (%BFtrunk) and lean body mass (LBM) . We also evaluated total cholesterol (COLtotal), HDL-cholesterol (HDL), triglycerides (TRI), fasting glucose (GLU) and insulin. The intervention consisted of concurrent training (50% of the time of aerobic exercise and 50% of resistance exercise), the sessions lasts 60 minutes of duration, 3 times per week for 20 weeks. Statistical analysis: we calculated the median and interquartile range of all variables and the Wilcoxon... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Desempenho de diferentes equações antropométricas na predição de gordura corporal excessiva em crianças e adolescentes

OBJETIVO: O objetivo do presente estudo foi analisar a eficiência de diferentes equações antropométricas para a identificação de excesso de gordura corporal entre crianças e adolescentes. MÉTODOS: A amostra foi composta por 1.498 indivíduos (678 meninos e 820 meninas), com idade entre 7 e 17 anos (M=13,7, DP=2,0), da cidade de Presidente Prudente (SP). A massa corporal e a estatura foram mensuradas para o cálculo do Índice de Massa Corporal. Também foi realizada a mensuração da circunferência de cintura e das dobras cutâneas subescapular, tricipital, abdominal e da panturrilha. O percentual de gordura corporal foi calculado por meio de quatro equações: Slaughter et al., Slaughter II et al., Dezenberg et al., e Deurenberg et al.. Para indicar a eficiência das diferentes equações antropométricas na indicação da obesidade, foi utilizada a análise da curva Receiver Operating Characteristic Curve. RESULTADOS: No grupo masculino, foram observados valores de sensibilidade elevados (82,4% a 100,0%) e valores oscilando de baixo a alto, para a especificidade (20,9% a 94,9%). Para o sexo feminino, os valores de sensibilidade variaram entre moderado e alto (72,2% a 99,4%); e os de especificidade apresentaram, também, grande oscilação entre baixo e alto (21,6% a 98,2%). CONCLSÃO: A equação proposta por Deurenberg et al., apresentou o melhor desempenho no diagnóstico tanto da presença como da ausência de obesidade na amostra investigada.OBJECTIVE: The purpose of this study was to analyze the efficiency of different anthropometric equations that identify excess body fat in children and adolescents. METHODS: The sample consisted of 1,498 subjects (678 males and 820 females), aged 7 to 17 years (13.7 SD=2.0), from Presidente Prudente (SP). Body weight and height were measured to calculate body mass index. Waist circumference and triceps, abdominal, and thigh skinfold thicknesses were also measured. The percentage of body fat was estimated by four anthropometric equations: Slaughter et al., Slaughter II et al., Dezenberg et al., and Deurenberg et al.. The Receiver Operating Characteristic Curve was used to indicate the efficiency of these equations. RESULTS: High sensitivity values (82.4% to 100,0%) and high and low specificity scores (20.9% to 94.9%) were observed in males. In females, the sensitivity values ranged from moderate to high (72.2% to 99.4%) and the specificity scores were high (21.6% to 98.2%). CONCLUSION: The Deurenberg et al., equation was the most accurate for identifying presence or absence of obesity in this sample

Effect of concurrent training on gender-specific biochemical variables and adiposity in obese adolescents

Objective The purpose of the present study was to analyze the effects of a 20-week concurrent training (20 WCT) intervention program on gender-specific body composition and metabolic variables in obese adolescents.Subjects and methods Sample was composed of twenty-five obese adolescents, aged between 12 and 15 (13.4 ± 0.96) years. Fat-free mass (FFM), percentage trunk fat mass (TFM%) and percentage fat mass (%FM) were evaluated through dual-energy X-ray absorptiometry (DXA). Measurement of intra-abdominal adiposity (IAAT) was performed using ultrasound. Blood pressure was measured and blood samples analyzed for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), triglycerides (TG) and plasma glucose. All participants performed the concurrent training (combination of weight training and aerobic training) three times per week, one hour per day, for 20 weeks. Descriptive analysis and analysis of variance (ANOVA) for repeated measures were used to compare baseline, 10 week and 20 week moments using the Bonferroni post-hoc test. Statistical significance was set at p < 0.05. Significant decrease in TC, LDL-c and TFM% were verified in both genders after the 10 initial weeks of concurrent training.Results A significant increase in height was found in both the male and female groups (p = 0.001 and p = 0.047, respectively), after 20 weeks of concurrent training. In addition, several modifications were observed in body composition and metabolic variables, with a significant decrease in BMI (p = 0.002 and p = 0.017), BMI z-score (p = 0.033 and p = 0.004), FM% (p = 0.002 and p = 0.002), TFM% (p = 0.009 and p = 0.018), TC (p = 0.042 and p = 0.001) and LDL-c (p = 0.006 and p = 0.001) in the male and female groups, respectively, after 20 weeks of intervention when compared with baseline.Conclusion Our results identified that concurrent training was an effective intervention for treating metabolic variable and body composition disorders, in both genders, by decreasing adiposity with consequent improvement in BMI and BMI z-scores, and enhancement in lipid profile variables

Body composition variables as predictors of NAFLD by ultrasound in obese children and adolescents

Background: Nonalcoholic fatty liver disease (NAFLD) is a disorder associated with excessive fat accumulation, mainly in the intra-abdominal region. A simple technique to estimate abdominal fat in this region could be useful to assess the presence of NAFLD, in obese subjects who are more vulnerable to this disease. The aim of this cross-sectional study was to verify the reliability of waist circumference and body composition variables to identify the occurrence of NAFLD in obese children and adolescents.Methods: Sample was composed of 145 subjects, aged 11 to 17 years. Assessments of waist circumference (WC), trunk fat mass (TFM) and fat mass (FM) by dual-energy X-ray absorptiometry (DXA) and ultrasound for diagnosis of NAFLD and intra-abdominal adipose tissue (IAAT) were used. Correlation between variables was made by Spearman's coefficients; ROC curve parameters (sensitivity, specificity, area under curve) were used to assess the reliability of body composition variables to assess the presence of NAFLD. Statistical significance was set at 5%.Results: Significant correlations were observed between NAFLD and WC (p = 0.001), TFM (p = 0.002) and IAAT (p = 0.001). The higher values of area under the ROC curve were for WC (AUC = 0.720), TFM (AUC = 0.661) and IAAT (AUC = 0.741).Conclusions: Our findings indicated that TFM, IAAT and WC present high potential to identify NAFLD in obese children and adolescents