Análises morfológicas de granulomas hepáticos gerados por infecção de Schistosoma mansoni em modelo animal e efeito de diferentes terapias

Abstract

Schistosomiasis is a parasitic disease that affects thousands of people around the world. It is a serious, neglected disease that affects the portal vascular system (mesenteric vein) where adult parasites deposit their eggs and cause comorbidities such as portal hypertension, generating vascular and hemorrhagic disorders, caused by fibrous granulomas that form around the eggs. Schistosomiasis granuloma is the central aspect of the pathogenesis of schistosomiasis where it is formed through inflammatory responses stimulated by antigens present in the egg. However, the treatment of schistosomiasis still depends exclusively on chemotherapy with Praziquantel, but the success with drug treatment through the PZQ has not eradicated schistosomiasis, which still remains a major concern in the health area. Thus, the search for new schistomicidal compounds has been gaining strength and in this sense natural compounds such as flavonoids, especially aurones, has been arousing great interest in the scientific community. The aim of the study was to analyze the dynamics of granuloma in animals infected and treated with praziquantel and synthetic aurones and to analyze the influence of the main hematological dyes in the analysis of schistosomiasis granulomas. For the present work, an experimental laboratory study was carried out, with a quali-quantitative character, using albino mice of the Swiss lineage, which were submitted to bisexual infection, by subcutaneous route, with approximately 100 cercariae/animal. The animals were divided into a control group, groups treated with PZQ (praziquantel/400mg/Kg/ Oral) and synthetic aurones (LS26 and LS29), in the dosages of 50 and 100mg, and in single-dose and two-dose treatment regimens. At the end of 55-60 days post-infection, the animals were euthanized. Liver fragments were fixed (right lobes), embedded in paraffin and cut (5µm). The prepared slides were stained with hematoxylin/eosin, gomory trichrome and Picrosirius. Granuloma areas were measured (10x objective) and multinucleated giant cell count (CGM - 40x objective) was performed using the ZEIN Lite 2012 program. Comparison of area means and number of granulomas observed in the 3 stains did not show significant differences (p > 0.05 with CV greater than 30%). In the evaluations of the areas of the granulomas, it was observed that the aurones LS26 and LS29 (100mg/2 doses) presented means of smaller areas and significantly different from PZQ. The evaluation of the GMC count revealed the presence of a greater quantity of these cells in the slides of animals treated with LS26 aurona (100mg/Kg – 2 doses).