All persons experience psychological stress. In fact, its pervasiveness is the primary cause of countless diseases. Although the impact of psychological stress on Parkinson’s disease (PD) has yet to be fully defined, there is ample evidence that PD symptoms worsen during times of stress. Therefore, we asked what would happen if a pre-clinical model with a known genetic vulnerability to PD was subjected to chronic psychological stress.
In order to address this question, we will subject two types of pre-clinical model to chronic psychological stress beginning two days after birth and ending at the end of adolescence. Three months after the final day of stress we will examine cell death in brain structures affected by PD.
Relevance to Diagnosis/Treatment of Parkinson’s Disease:
Discovering that psychological stress may be a risk factor for PD would be an enormously important finding that may, in part, explain how people across different cultures, environments, etc., eventually develop PD. This observation, coupled with future studies, may indentify a common mechanism(s) shared by the majority of PD patients that can be translated to early diagnostics and new therapeutics.
We hypothesize that the combination of a genetic deficiency plus chronic stress will increase the extent of brain cell loss in PD-associated brain structures. If this is the case, then future studies will be aimed at identifying the mechanisms through which this occurs.
Our studies demonstrated that chronic psychological stress increased resting levels of inflammation, a factor that, when increased, has been shown to facilitate nigral cell death. These data suggest that chronic psychological stress might have deleterious consequences in an environment where inflammation is primed to facilitate cell death. Our group continues to explore this hypothesis.
Presentations & Publications
1. Barnum, C.J., Pace, T.W.W, Hu, F., Neigh, G.N., Tansey, M.G. Psychological stress in adolescent
and adult mice increases neuroinflammation and attenuates the response to LPS challenge. Journal
of Neuroinflammation, 9(1), 9.
2. Barnum, C.J., Pace, T.W.W, Hu, F., Neigh, G.N., Tansey, M.G. Predatory stress increases markers
of inflammation within the midbrain and hippocampus and leads to the development of
x depressive-like behaviors in pre-clinical models. XI National Parkinson’s Disease Foundation symposium on PD:
Targeting non-motor symptoms, Washington DC 2011.