Relation between acetylcholinesterase and Na+, K+-ATPase activities with impaired memory of mice experimentally infected by Trypanosoma cruzi

Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and causes severe cardiac and brain damage, leading to behavioral alterations in humans and animals. However, the mechanisms involved in memory impairment during T. cruzi infection remain unknown. It has long been recognized that the enzymatic activities of acetylcholinesterase (AChE) and Na+, K+-ATPase are linked with memory dysfunction during other trypanosomiasis. Thus, the aim of this study was to evaluate the involvement of cerebral AChE and Na+, K+-ATPase activities in the memory impairment during T. cruzi (Colombian strain) infection. A significant decrease on latency time during the inhibitory avoidance task was observed in animals infected by T. cruzi compared to uninfected animals, findings compatible to memory dysfunction. Moreover, the cerebral AChE activity increased, while the Na+, K+-ATPase decreased in T. cruzi infected compared to uninfected animals. Histopathology revealed mild to moderate multifocal gliosis in the cerebral cortex and light focal meningeal lymphoplasmacytic infiltrate, which may have contributed to memory loss. Based on these evidences, we can conclude that T. cruzi (Colombian strain) causes memory impairment in mice experimentally infected. Moreover, the changes in AChE and Na+, K+-ATPase activities may be considered a mechanism involved in disease pathogenesis.