Avaliação do perfil glicêmico, leucocitário e nutricional de ratos Wistar submetidos a diferentes regimes de redução de Prednisona

Abstract

Prednisone is one of the most widely used glucocorticoids, with immunosuppressive and antiinflammatory effects. Prednisone needs to be gradually reduced due to its many side effects and the suppression of the hypothalamic-pituitary-adrenal axis in chronic use, but there is no consensus in the literature on the best reduction protocol. The aim of this study was to evaluate the glycemic, leukocyte and nutritional profile of Wistar rats submitted to different Prednisone reduction protocols. 38 adults male Wistar rats were used, divided into 5 groups and treated with Prednisone and/or vehicle for 28 days. Group C- (10) received the vehicle (Syrspend®) for 28 days; C+ (n=7) received prednisone 5mg/kg for 28 days; GR (n=7) received prednisone 5mg/Kg for 14 days then replaced with Syrspend®; GR1 (n = 7) received prednisone 5mg/Kg for 14 days, from the 15th day reduced to 2.5mg/Kg on the 21st day replaced by Syrspend®; GR2 (n = 7) received prednisone 5mg/Kg for 14 days and on the 15th day 50% every three days on the 27th day replaced by Syrspend®. Treatment was oral and daily. Body weight, 24-hour food and water consumption were assessed weekly. Total and differential leukograms were taken on days 0, 14 and 28. The oral glucose tolerance test (OGTT) was carried out on day 27. At the end, the rats were euthanized and the organs surgically harvested and weighed. From the data obtained, the area under the curve (ASC), minute glucose rate (MGT), nutritional calculations and Pearson's correlation were performed. Results were considered statistically significant when p<0.05. There was no statistical difference in the nutritional parameters of the C-, C+, GR1 and GR2 groups, but the GR group had an increase in the specific rate of weight gain at week 4 compared to week 1. In the TOTG, there was an increase in blood glucose at 30 minutes in the C+, GR, GR1 and GR2 groups compared to the C- group, and at 60 minutes in the C+ and GR1 groups compared to the C- group. There was an increase in ASC in the C+ group compared to the C- group at time 60-120mi, as well as an increase in total ASC in the C+, GR, GR1 and GR2 groups compared to the C- group. The TGM of groups C+, GR1 and GR2 at 30-60 minutes showed an increase in glycemia compared to the fasting group at 30 minutes. In the leukogram, group C- showed an increase in the total leukocyte count on day 28 compared to day 0. In the differential count, group C- had an increase in lymphocytes on day 28 compared to day 0, and an increase in neutrophils on day 28 compared to days 0 and 14. There was no statistical difference in the Pearson correlation and relative organ weight. Therefore, the GR1 and GR2 groups had no negative repercussions on the immunological and nutritional profile, despite maintaining hyperglycemia during the TOTG. Further studies are needed to confirm the best reduction protocol, considering the individuality of each pathology and condition.