Estudo comparativo do pâncreas de camundongos C57BL/6 em diferentes momentos de infecção com Trypanosoma Cruzi

Abstract

American Trypanosomiasis, or more commonly known, Chagas Disease (CD), is currently one of the most important endemic anthropozoonosis. It is caused by the Trypanosoma cruzi protozoan (T. cruzi). T. cruzi can be found in different sites inside the vertebrate host; the blood trypomastigote forms predominate in the acute stage, as well as the amastigote infection is present all organ and systems. The parasite load is an important factor that influences the progress of the acute stage, and consequently, the disease, and are linked to heart, intestinal and kidney changes. Diabetes and Chagas disease was related in previous studies, but pancreatic changes in Chagas Disease were little studied and focused in functional studies of carbohydrate metabolism and exocrine pancreas, mainly in the indeterminate and critical forms of the disease. Here we did establish acute and chronic chagasic infection in male C57BL/6 mice with Y strain and access parasitaemia, pancreatic inflammatory infiltrate, mortality and pancreatic histopathology, morphometry and functionality with Intraperitoneal Glucose Tolerance Test (TITG) and plasma insulin quantification. Trypanosoma cruzi infection leads to parasitism, and consequent morphological and functional changes in the pancreas, in an inoculum dependent way. High parasite load leads to an aggressive acute infection with high parasitemia, mortality and smaller tissue parasitism, with slight pancreatic changes (structural and functional). Lower parasite load leads to marked pancreatic parasitism, with intense associated inflammatory infiltrate, reduction of the pancreatic islet area, associated with lower plasma insulin and glycemia. At chronic phase mice with different inocula similarly maintained the parasitism and the pancreatic inflammation and lower plasma insulin. These different pancreatic changes in relation to different parasite loads can be important parts in the wide variation puzzle of clinical and metabolic changes that are associated with Chagas Disease.