Efeito da suplementação de leucina na cardiotoxicidade de ratos tratados com doxorrubicina

Abstract

Introduction: Doxorubicin is an important chemotherapeutic agent used in oncology, howe-ver, its cardiotoxic effect limits its therapeutic use and generates problems regarding the prognosis of patients. Leukemia is a branched-chain amino acid used in dietary supplemen-tation and has been less as a strategy for the adverse effects of oxidative stress, at least they have been attributed to increased stress in animals, oxidized in part have been attribu-ted to increased stress. in animals. Objectives: The objective of the study was to analyze the action of leucine on cardiotoxicity by doxorubicin in rats. Material and Methods: Wistar strain media with a mean age of three months and body weight of 274g were used, which were separated into four groups designated as Control (C), Doxorubicin (D), Leucine (L), Leucine + Doxorubicin (LD). The animals in groups D and LD received intraperitoneal injec-tions of doxorubicin hydrochloride times a week, at a dose of 1.25 mg/kg each, over two weeks, until reaching a total cumulative dose of 7.5 mg/kg; the other groups received intra-peritoneal injections of saline solution, in a similar volume. The L and LD groups received a diet with 5% leucine supplementation. Measures were taken to prevent data from the ani-mals and their topological views were performed; dosages of SOD, catalase and AKT - mTOR were performed. The analysis of heart rate variability was performed in groups C and D. Results: The hearts of the animals in group D showed higher expression of type I and total collagen fibers when compared to groups C, L and LD. There was lower expression of cardiac catalase in groups L and LD when compared to control. Conclusion: Doxorubicin increases cardiac production of type I and total collagen; Leucine supplementation reduces collagen and catalase levels in the heart, which may be linked to attenuation of cardiotoxicity via reduced oxidative stress. Doxorubicin reduces heart rate variability, with greater action on the sympathetic pathway.