Corticosterone mediates the effects of chronic stress on Theiler's virus in mice

Abstract

Theiler's Murine Encephalomyelitis Virus in mice is a clinically relevant model of multiple sclerosis (MS) since the current hypothesis is that a viral infection may be the initiating event in the development of MS. Chronic restraint stress profoundly affects vulnerability to the acute phase of Theiler's virus. This study confirms that restraint results in higher mortality rates, more severe clinical signs and decreased body weights in mice restrained and infected with Theiler's virus compared to nonstressed-infected mice. Two experiments identified the mediator of these effects as corticosterone, a stress hormone released by the HPA axis. The first experiment found that restraint stress elevated corticosterone levels, and the second experiment found that administration of exogenous corticosterone produced immune suppressive effects similar to restraint (mortality, increased symptomatology, decreased body weight).