Study of therapy effectiveness of indomethacin and ethyl ester indomethacin nanocapsules: intravital microscopy assays

Abstract

In recent years, nanotechnology has emerged as an important tool for the development of new products in various areas of academia and the private sector, including those of pharmaceutical sciences. Among the products available in the pharmaceutical nanotechnology, nanoparticle systems are highlighted by providing sustained vectoring and by acting as carriers of drugs, increasing the therapeutic efficacy. These characteristics are essential for the treatment of many diseases, among them, cancer. Despite the many advantages of anti-neoplastic nanoparticles, pharmacological and toxicological parameters of this therapeutic strategy must be better understood. Thus, this study aims to implement the intravital microscopy assay to evaluate some paramaters of the therapeutic efficacy, not yet addressed in Brazil, by studying the anti-carcinogenic activity and toxic effects in the microcirculation caused by nanocapsules of indomethacin and indomethacin ethyl ester and its formulations usual. For this, tests will be performed in C57BL6 female mice, adult, using labeled fluorophores nanocapsules. The distribution and its effects will be measured in brain tissue in the presence of brain tumor formation induced by intracranial inoculation of cells from the lineage of malignant glioma GL261. Besides the distribution of the nanocapsules in the microcirculation, it will be analyzed leukocyte-endothelium interactions, leukocyte-platelet and platelet-endothelium, thrombus formation and hemorrhagic areas in the cerebral microcirculation vessels. Complementing the intravital microscopy assays, the effect of nanocapsules on the integrity of blood-brain barrier is determined by ex vivo test (solution of Evans 'blue') and therapeutic efficacy of the compounds will be evaluated by measuring the kinetics of tumor formation in brain by means of histological tests and "western blot". It is hoped that this project provides a set of in vivo and ex vivo strategies to assess the therapeutic and toxic activity of the nanocapsules targeted anticancer drugs and to contribute to the knowledge of the toxic actions of these nanocapsules in microcirculatory network. In addition, this project will allow the implementation of the intravital microscopy methodology in non-trans-illuminated tissues, not yet addressed in our laboratory, and not common research strategy in Brazil. In this context, this project will contribute to other projects in progress in our laboratory, which aim to investigate the vectoring of other nanocapsules for the liver tissue; the investigation of persistent organic pollutants on the pancreatic microcirculation; and the action of PPARs agonists on the gastric microcirculation during gastric ulcer development. The project will include the effective participation of Dr. Stephen de Paula Rodrigues, a postdoctoral fellow in our laboratory, which has gained experience in scientific and technical intravital microscopy during the course of Ph.D. under the supervision of Dr. Zuleica Bruno Fortes, from the Department of Pharmacology Institute of Biomedical Sciences, USP, and during the post-doctoral internship at the Laboratory of Microcirculation Laboratory, supervised by Dr. Neils Granger, at the LSU Health Sciences Center, Shreveport, LA, United States. (AU)