Projects Hidden Sorrows of Covid-19

Hidden Sorrows of Covid-19: Impact of Stress on Parkinson’s disease Progression

Parkinson’s disease (PD) is caused by progressive loss of nigro-striatal dopamine cells. Converging clinical evidence indicates that PD patients are very sensitive to the effects of psychological stress.

Main applicant: Dr. Rick Helmich

Affiliation(s): Radboud university medical centre, Nijmegen (NL); Donders Center of Medical Neurosciences, Nijmegen (NL)

Abstract: Parkinson’s disease (PD) is caused by progressive loss of nigro-striatal dopamine cells. Converging clinical evidence indicates that PD patients are very sensitive to the effects of psychological stress. There is a high prevalence of stress-related neuropsychiatric symptoms in PD, and stress worsens many motor symptoms. Moreover, chronic stress may also have detrimental long-term consequences, specifically by accelerating disease progression, as suggested by animal models. In this study, we aim to test the hypothesis that psychological distress accelerates nigro-striatal cell loss in PD, and that this effect is mediated by increased inflammatory tone. In humans, the relationship between chronic stress and rate of PD progression is still unknown: it is unethical to deliberately expose individuals to potentially harmful effects of chronic stress. This knowledge would have major treatment consequences: novel stress-reducing interventions may have symptomatic effects, and perhaps also disease-modifying effects. We and others have previously shown that social isolation measures during the covid-19 pandemic have caused considerable psychological distress in PD patients. Here, we will investigate if and how a real-life stressor (covid-19 pandemic) influences PD progression. Stress hormones (e.g. cortisol) affect major immune functions by increasing microglia activation, which is also present in PD. Neuroinflammation precedes neurodegeneration in the substantia nigra, suggesting a causal relationship. Indeed, previous research has shown that several inflammatory cytokines are increased in the serum of PD patients. Thus, we expect that the detrimental effects of stress on neurodegeneration may be mediated by increased systemic inflammation.

Related publications: The Impact of the COVID-19 Pandemic on Psychological Distress, Physical Activity, and Symptom Severity in Parkinson’s Disease - IOS Press