Avaliação da atividade lisossomal de células de cérebro e fígado de gerbis (Meriones unguiculatus) infectados “in vitro” com Neospora caninum

Abstract

Neospora caninum is a coccidial protozoan that cause agent of neosporosis, a disease of worldwide occurrence characterized by causing abortion and neonatal alterations. This parasite has cattle, goats and buffaloes as intermediate hosts, while dogs and coyotes are definitive hosts. Whereas N. caninum is an obligate intracellular parasite is believed that infection with this parasite can interfere with the activity of the celular organelles, these organelles among the highlights are the lysosomes, the center of primary degradation of the cell. The aim of this work was analyze the level of catalytic enzymes, Monoester-Ortofosforica fosfohidrolase – EC 3.1.3.2, present in lysosomes of the brain and liver of 20 gerbils (Meriones Unguiculatus), 10 were experimentally infected and 10 controls. Animals were infected subcutaneously with 5x105 tachyzoites of NC-Bahia strain and after three days were euthanized. Lysosomal fraction was obtained by fractionated centrifuge. The acid phosphatase present in the lysosomes of brain and liver of gerbils was measured using a commercial kit. Control animals had an activity of brain for acid phosphatase 34.3 ± 5.7 IU/μg total protein/mL, while the infected animals was of 26.9 ± 3.7 IU/μg total protein/mL. Since the average acid phosphatase activity of liver cells to the control animals was 28.3 ± 2.5 IU/μg total protein/mL and 8.7 ± 6.8 IU/μg total protein/mL in the infected animals. Based on these results, we can conclude that the lysosomal stability found in the infected group, probably represents a defense mechanism of the parasite against acidic hydrolytic enzymes contained in lysosomes primary.