Experimental assessment of the diabetogenic potential of bovine enterovirus in Wistar rats

The involvement of enteroviruses in the development of type 1 diabetes (T1D) has been long studied, since they may affect the insulin producing β cells directly or may act in the pathology through the development of autoimmunity. Therefore, this study investigated the effects of exposure of an animal model (Wistar rats) to bovine enterovirus (BEV) through biochemical, histological, molecular and immunological analyses. Male Wistar rats were divided in five groups: control, enterovirus, immunized with oil-adjuvanted BEV-vaccine, immunized and challenged with BEV (immunized+enterovirus) and streptozotocin (STZ) treated. Stools specimens were collected during the experimental period and after, the animals were killed for blood and tissue collection. An increase of blood glucose levels was observed in the immunized, immunized+enterovirus and STZ groups, while morphological alterations in islets and increased anti glutamic acid decarboxylase (GAD) antibodies were only observed in the STZ animals. The presence of viral RNA in stools was ascertained in the groups which ingested the contaminated water. Thus, BEV did not induce clinical diabetes in orally infected rats, but immunization with inactivated BEV lead to blood glucose metabolism impairment.