Lippia Aff. Gracilis, Lippia Gracilis e L-Glutamina e suas ações antibacteriana, antioxidante e imunomoduladora em modelos de ratos diabéticos

Abstract

The antibacterial effect of essential oils extracted from leaves of the species of Lippia aff. gracilis and Lippia gracilis against strains of Staphylococcus aureus isolated from patients with diabetic foot ulcers were evaluated in vitro and in vivo experimetation utilizing an experimental model of alloxan-induced diabetic rats. One hundred and twelve male diabetic Wistar rats with mean weight of 180g were distributed by chance into two experiments. Each experiment was divided in two procedures with evaluation of antibacterial activity of essential oils at 5% solutions; one procedure in the act of administration of bacterial inoculums and the other one 24 hours later. 108 CFU (Colony Forming Unit) /mL, as well as oils suspension inoculated in the subcutaneous tissue of the pelvic member of diabetic rats. Lower than 5% concentration of administered solution presented antibacterial effect in the in vitro experiment. Fifty-six Wistar rats were utilized in each experiment, randomly distributed in 08 different groups: 04 groups per experiment, each group with 07 rats (G1-White; G2-Negative Control; G3- Positive control; G4-Test). There was decrease in CFU/mL in procedure 1 (S.aureus without Lippia aff gracilis 108 ± 698 versus S.aureus with Lippia aff gracilis 293,1 ± 9,07; S.aureus without Lippia gracilis 108 ± 873 versus S.aureus with Lippia gracilis 302±57,2), which evaluated antibacterial effect of oils concomitantly with the administration of inocula as well as in procedure 2 (S.aureus without Lippia aff gracilis 108 ± 313 versus S.aureus with Lippia aff gracilis 13,28 ± 4,03; S.aureus without Lippia gracilis 108 ± 818 versus S.aureus with Lippia gracilis 13,14 ± 4,27) , which evaluated antibacterial effect of oils 24 hours after the administration of the inoculum . When comparing group G4 with G3, it was observed that 5% solution presented no pro-inflammatory effect, for analysis of these results, the tests of Mann-Whitney and Bartletts & Newman-Keuls (X ± S.E.M) with level of significance (p<0,05) were used. Part of this study evaluated the antioxidant and immunomodulating effect of L-glutamine in models of Wistar diabetic rats when administered by gavages at a 0,7g/kg during 30 days. Fourty Wistar male rats were randomly distributed in 5 groups (GI- non diabetic; GII-diabetic; GIII-diabetic with saline; GIV- diabetic with L-glutamine; GV- diabetic with Whey Protein). After 30 days concentrations of TBARS and GSH in serum and in hepatic, pancreatic, skeletal muscles, kidneys and fat tissues were determined. For comparisons between the group treated with L-glutamine with the others, the ANOVA – Tukey test was utilized and the comparisons between groups were done using Student’s t test. Values of p<0.05 were considered significant. The supplementation with L-glutamine induced an increase in the concentrations of GSH (Mean±S.E.M) and significant reduction in the TBARS (mean ± S.E.M) concentrations, when compared to the control group, in the analyzed specimens. The immunomodulating effect was evaluated by quantification of CD4+ and CD8+ lymphocytes in total blood. Twenty-four Wistar male diabetic rats were distributed equally in 3 groups (G1-diabetic with saline; G2-diabetic with L-glutamine; G3- diabetic with Whey Protein). It was seen a significant increase of CD4+ (mean ± S.E.M) lymphocytes with reduction of CD8+ (mean ± S.E.M) lymphocytes in group G2 when compared to the control group, showing the importance of L-glutamine as an immunonutrient.