Pathological vicissitudes and oxidative stress enzyme responses in mice experimentally infected with reptarenavirus (isolate UPM/MY01).

Abstract

Boid inclusion body disease (BIBD) is a viral disease of boid snakes believed to be caused by reptarenavirus belonging to the family Arenaviridae. Unlike most mammalian arenaviruses, the reservoir host for reptarenavirus is still unknown. In this study, the pathological responses were evaluated in a mouse model for a period of 28 days. Blood and tissue samples (lung, liver, spleen, heart, kidney and brain) were collected for evaluation of hematology, biochemistry, histopathology and oxidative enzyme levels at six time points (1, 3, 7, 14, 21 and 28 days), after viral infection (2.0×106pfu/mL) in the infected and normal saline in the control groups. An initial increase (p<0.05) in white blood cell (WBC), neutrophil and lymphocyte counts were observed in the infected group at day 3 post infection, and a decline (p<0.05) on day 7 and 4 post infection. Significant (p<0.05) increases in alanine transaminase (ALT), aspartate transaminase (AST), creatinine, total protein and globulin levels were also observed in the infected group. An increased (p<0.05) level of hydrogen peroxide, total antioxidant capacity (TAC), superoxide dismutase (SOD) activity and catalase activity (CAT) were frequently observed on different days in the infected group. The MDA activity was increased (p<0.05) in the infected group on day 7 and 14. Histopathological changes observed in the liver, kidney, spleen, brain and lungs were mainly associated with degeneration, necrosis and infiltration of lymphocytes. Viral counts were low on days 7 and 14 but surged in both the liver and spleen on day 21 and 28. This study has shown that reptarenavirus replicates in mammalian host and induces oxidative stress. Furthermore, the resultant hematobiochemical and histopathological changes observed in infected mice were similar to what has been reported in mammarenavirus infections. This suggests that rodents may serve as potential reservoir hosts for reptarenavirus.