Abstract Objective: To determine possible changes in serum concentrations of pro- and anti-inflammatory cytokines of eutrophic rats subjected to aerobic or resistance physical training. Methods: This study examined serum concentrations of TNF-α, IFN-γ, IL-6, IL-10 and IL-1-β in rats that performed aerobic or resistance training for 16 weeks. Thirty-five Wistar rats (male adult) were divided into three groups: Control Group (CG), Aerobic Group (AG) and Resistance Group (RG). Rats were sacrificed 48 h after the final training session. Serum concentrations of cytokines were analysed by ELISA. Results: TNF-α levels were higher in the RG, followed by the AG and CG groups (p < 0.001). IFN-γ and IL-10 levels were not significantly different between groups (p = 0.097 and p = 0.17, respectively). The levels of IL6 and IL1-β were higher in AG compared to RG and CG (p = 0.0004 and p = 0.003, respectively). In general, our results indicate a higher pro-inflammatory profile in AG and probably RG animals. Conclusion: Further studies are required in order to better clarify the effects of aerobic and resistance exercise training on pro- and anti-inflammatory cytokines. Additionally, future studies should address the metabolic and molecular pathways involved in these responses.

Resumo Objetivo: Determinar as possíveis alterações nas concentrações séricas de citocinas pró e anti-inflamatórias de ratos eutróficos submetidos a treinamento físico aeróbio ou resistência. Método: Este estudo examinou a concentração sérica de TNF-α, IFN-γ, IL-6, IL-10 e IL-1-β em ratos que realizaram treinamento aeróbio e de resistência durante 16 semanas. Trinta e cinco ratos Wistar (macho adulto) foram divididos em 3 grupos: grupo controle (GC), grupo aeróbico (GA) e grupo de resistência (GR). Os ratos foram sacrificados 48 horas após a sessão de treino final. As concentrações séricas de citocinas foram analisadas por ELISA. Resultados: Os níveis de TNF-a foram maiores no GR, seguindo-se os grupos GA e GC (p < 0.001). IFN-γ e os níveis de IL-10 não foram significativamente diferentes entre os grupos (p = 0.097 e p = 0.17, respectivamente). Os níveis de IL-6 e IL-1-β foram maiores em GA, quando comparados com GC e GR (p = 0.0004 e p = 0.003, respectivamente). Em geral, os nossos resultados indicam um perfil pró-inflamatório maior nos animais do GA e, provavelmente, no GR. Conclusão: Mais estudos são necessários para melhor esclarecer os efeitos do treinamento físico aeróbico e resistência sobre as citocinas pró e anti-inflamatórias. Além disso, estudos futuros devem abordar as vias metabólicas e moleculares envolvidas nestas respostas.

Resumen Objetivo: Determinar posibles cambios en las concentraciones séricas de citoquinas pro y antiinflamatorias de ratas eutróficas sometidas a entrenamiento físico aérobico y de resistencia. Método: Se examinaron las concentraciones séricas de TNF-α, IFN-γ, IL-6, IL-10 e IL-1-β en ratas sometidas a entrenamiento aeróbico o de resistencia de 16 semanas de duración. Treinta y cinco ratas Wistar (macho adulto) fueron divididas en 3 grupos: Grupo Control (GC), Grupo Aeróbico (GA) y Grupo Resistencia (GR). Las ratas se sacrificaron 48 horas después de la sesión de entrenamiento final. Las concentraciones séricas de las citoquinas se analizaron por ELISA. Resultados: Los niveles de TNF-α fueron mayores en el GR, seguido por los grupos de GA y GC (p < 0.001). Los niveles de IFN-γ e IL-10 no fueron significativamente diferentes entre los grupos (p = 0.097 y p = 0.17, respectivamente). Los niveles de IL-6 y IL-1-β fueron mayores en GA comparado con GR y GC (p = 0.0004 y p = 0.003, respectivamente). En general, nuestros resultados indican mayor perfil antiinflamatorio en GA y probablemente en GR. Conclusión: Se necesitan estudios adicionales para aclarar mejor los efectos de un entrenamiento aeróbico o de resistencia en las citoquinas pro y antiinflamatorias. Además, los estudios futuros deben abordar las vías metabólicas y moleculares involucradas en estas respuestas.

Dado que o diabetes mellitus é considerado um problema de saúde pública mundial, o presente estudo objetivou avaliar a tolerância à glicose oral (TTGo) e concentrações de insulina pancreática (CIP) de ratos diabéticos tipo 1 submetidos a um protocolo de treinamento físico individualizado. Foram utilizados 40 ratos Wistar adultos, onde metade foi induzida ao diabetes por meio de injeção endovenosa de aloxana (32 mg/kg), divididos em quatro grupos (10 por grupo): Controle Sedentário (CS), Controle Treinado (CT), Diabético Sedentário (DS) e Diabético Treinado (DT). O treinamento físico consistiu de natação, 1 h/dia, 5 dias/semana durante 8 semanas, com sobrecarga equivalente a 90% da transição metabólica aeróbia/anaeróbia determinada no início do experimento. Os ratos dos grupos DS e DT apresentaram redução de peso corporal em relação aos controles, a qual foi menos acentuada no grupo DT. As ingestões hídrica e alimentar aumentaram nos grupos diabéticos em relação aos controles. Durante o TTGo, os valores de área sob a curva glicêmica dos grupos diabéticos foram superiores aos dos controles. O treinamento físico atenuou esta elevação. Os grupos diabéticos apresentaram CIP reduzida quando comparados aos grupos controles. O protocolo de treinamento físico empregado, embora não tenha alterado a CIP, melhorou a homeostase glicêmica e atenuou a perda de peso corporal dos animais diabéticos.

Since diabetes mellitus is considered a world public health problem, the present study aimed to evaluate oral glucose tolerance (TTGo) and pancreatic insulin concentration (PIC) of type I diabetic rats subjected to an individualized exercise training protocol. A total of 40 adult Wistar rats were used, half of which induced to diabetes by alloxan (32 mg/kg) endovenous injection, and divided into four groups (10 per group): Sedentary Control (SC), Trained Control (TC), Sedentary Diabetic (SD) and Trained Diabetic (TD). The physical training consisted of swimming, 1 h/day, 5 days/week during 8 weeks, supporting overload equivalent to 90% of the individual anaerobic/aerobic metabolic transition determined at the beginning of the experiment. The rats of SD and TD groups presented body weight reduction in relation to controls, which was less accentuated in TD group. Water and food ingestion increased in the diabetic groups in relation to controls. The areas under the serum glucose curve during the GTTo of diabetic groups were higher than the controls. Physical training attenuated this elevation. The diabetic groups showed reduced PIC when compared to both control groups. The physical training protocol employed improved glucose homeostasis and attenuated the body weight loss of diabetic animals but did not alter pancreatic insulin concentration.

The break point of the curve of blood lactate vs exercise load has been called anaerobic threshold (AT) and is considered to be an important indicator of endurance exercise capacity in human subjects. There are few studies of AT determination in animals. We describe a protocol for AT determination by the "lactate minimum test" in rats during swimming exercise. The test is based on the premise that during an incremental exercise test, and after a bout of maximal exercise, blood lactate decreases to a minimum and then increases again. This minimum value indicates the intensity of the AT. Adult male (90 days) Wistar rats adapted to swimming for 2 weeks were used. The initial state of lactic acidosis was obtained by making the animals jump into the water and swim while carrying a load equivalent to 50% of body weight for 6 min (30-s exercise interrupted by a 30-s rest). After a 9-min rest, blood was collected and the incremental swimming test was started. The test consisted of swimming while supporting loads of 4.5, 5.0, 5.5, 6.0 and 7.0% of body weight. Each exercise load lasted 5 min and was followed by a 30-s rest during which blood samples were taken. The blood lactate minimum was determined from a zero-gradient tangent to a spline function fitting the blood lactate vs workload curve. AT was estimated to be 4.95 ± 0.10% of body weight while interpolated blood lactate was 7.17 ± 0.16 mmol/l. These results suggest the application of AT determination in animal studies concerning metabolism during exercise.