Efeitos do treinamento muscular ventilatório combinado à laserterapia sobre o estresse oxidativo de ratos com diabetes mellitus tipo 2

Abstract

Introduction: Diabetes mellitus (DM) is considered one of the main non-communicable chronic diseases today. Among the main types, the most predominant is type 2 DM (DM2) which is related to oxidative stress, the increase in pro-inflammatory cytokines and the reduction in anti-inflammatory cytokines. Ventilatory muscle training (MVT) and low-intensity laser therapy (LLL) are nonpharmacological tools widely reported in the literature, promoting several benefits in different populations, however, little is known about the effects of the combination of these two therapies on oxidative stress in animals with DM2 induced by hypercaloric diet and streptozotocin. Objective: to evaluate the effects of combined therapy (CB) of LLLT and TMV on oxidative stress in rats with DM2. Method: Experimental research using male Wistar rats, allocated in one of the experimental groups below, totaling 8 animals per group: Group 1 - sedentary control animals without DM2 (CSham), Group 2 - animals without DM2 and CB ( CB- Sham), Group 3 - animals with DM2 sedentary (C-DM) and Group 4 - animals with DM2 and CB (CB-DM). T2DM was induced by means of a highfat diet and low dose streptozotocin (35 mg/kg) while the Sham groups received standard commercial diet. The TMV protocol was sold for 30min/day, 5 days/week for 6 weeks. LLL was applied in two points in the right gastrocnemius muscle, 5 days/week, for 6 weeks, at a dose of 21 J/cm and wavelength of 660nm. Twenty-four hours after the last day of intervention, the animals were euthanized and blood and tissues (heart, diaphragm, liver, right gastrocnemius, lungs and kidneys) were collected, weighed and homogenized for further analysis. Results: The combined protocol reduced the oxidative stress in the diaphragm of diabetic rats (increase of DCF-RS), in the gastrocnemius the combined protocol reduced the oxidative stress in the non-diabetic group (reduction of TBARS) however, there was an increase in oxidative stress in the gastrocnemius of diabetic rats that received the combined protocol compared to the other groups (increase in DCF-RS). There was no reduction in plasma oxidative stress in diabetic rats (reduction of TBARS). The combined protocol increased antioxidant activity in heart, lung, kidney and muscle in the diabetes group (increase in SH) and in heart, lung and diaphragm (increase in SOD). Data were compensated using GraphPad Prism statistical software. To verify the normality of the data used in the Kolmogorov-Smirnov test. Variables of more than two measures were compared by two-way ANOVA for repeated measures followed by Bonferroni post hoc. Continuous variables were detected as mean ± standard deviation (SD). Consider a significance level of p<0.05 for all tests. Conclusion: the combined protocol was effective in reducing oxidative stress in addition to increasing antioxidant activity in muscles, organs and plasma of animals with DM2.