Efeito do tratamento in vitro com a Liraglutida sobre células epiteliaisintestinais de ratos

Abstract

Glucagon-like peptide-1 (GLP-1) analogues are a new class of drugs developed to prolong the physiological effects of human endogenous GLP-1. Among these drugs, Liraglutide stands out for its importance in weight control and the regulation of blood glucose levels. However, some studies have shown some adverse effects in patients due to treatment with Liraglutide. The gastrointestinal tract was one of the most affected systems, in which about 81% of the patients reported mainly nausea, abdominal pain, diarrhea, and vomiting. Thus, the objective of this study was to evaluate in vitro the effects of Liraglutide on intestinal epithelial cells of normal rats (IEC-6) to highlight the possible cytotoxic actions triggered by this drug. IEC-6 cells were treated with Liraglutide (Victoza®, Novo Nordisk) at concentrations of 1, 0.5, and 0.25 M diluted in DMEM 2% containing fetal bovine serum for 24 hours. Cell viability was verified through MTT absorbance by IEC-6 cells. Apoptosis and necrosis of cells exposed to Liraglutide were evaluated by checking DNA degradation using acridine orange (LA) and propidium iodide (PI) dyes under a fluorescence microscope. A morphology assay was also carried out to verify morphological changes and the arrangement of actin fibers in IEC-6 cells. In this experiment, cells were stained with phalloidin conjugated to fluorescein and visualized under a fluorescence microscope. To analyze the motility of IEC-6 cells, the scratch wound healing assay was applied, in which cell migration was monitored under an inverted light microscope until the closure of an area free of cells. The graphics and statistical analyses were done using the GraphPad Prism program, version 7.00. The treatment with Liraglutide did not decrease cell viability at concentrations of 0.25, 0.5, and 1 M. Furthermore, the drug treatment decreased the rate of apoptosis in IEC-6 cells when compared to the control. In the morphology test, it was observed that some cells treated with Liraglutide had more elongated structures and decreased cytoplasm. Furthermore, the treated cells showed prominent stress fibers. When analyzing the cell migration, a decrease in the percentage of closure of the cell-free area was observed, mainly at 24 hours, compared to non-treated cells. These results showed that treatment with Liraglutide decreased apoptosis, interfered with the disposition of the actin cytoskeleton, and reduced cell migration in IEC-6 cells. However, further studies are needed to determine the role of this drug in the physiology of intestinal cells.