The Role of Stress as a Risk Factor for Progressive Supranuclear Palsy

Environmental Risk Factors for Progressive Supranuclear Palsy

Typically, progressive supranuclear palsy (PSP) is clinically characterized by slow vertical saccades or supranuclear gaze palsy, levodopa-resistant parkinsonism with predominant axial symptoms, and cognitive executive impairment. Over the past decades, various PSP phenotypes, including PSP with predominant parkinsonism, PSP with corticobasal syndrome, PSP with progressive gait freezing, and PSP with predominant frontal dysfunction, have been identified from pathologically confirmed cases. Expanding knowledge led to new diagnostic criteria for PSP that with increased disease awareness led to increased PSP prevalence estimates. The identification of environmental and modifiable risk factors creates an opportunity to intervene and delay the onset of PSP or slow disease progression. To date, despite the increasing number of publications assessing risk factors for PSP, few articles have focused on environmental and lifestyle risk factors for this disorder. In this article, we reviewed the literature investigating the relationship between PSP and several environmental and other modifiable lifestyle risk factors. In our review, we found that exposures to toxins related to diet, metals, well water, and hypertension were associated with increased PSP risk. In contrast, higher education and statins may be protective. Further case-control studies are encouraged to determine the exact role of these factors in the etiopathogenesis of PSP, which in turn would inform strategies to prevent and reduce the burden of PSP.

Stress and neurodegeneration

Neurodegenerative diseases are a great concern because of aging worldwide population. Despite substantial effort to advance our understanding of the etiology and potential treatment of neurodegeneration, there remains a paucity of information with respect to this complex disease process. Interestingly, stress has been implicated among the potential mechanisms implicated in neurodegenerative pathology. Given the increase in chronic stress in modern society, this premise warrants further investigation. The aim of this review is to evaluate the influence of stress on neurodegeneration, the effect of neurodegenerative diseases diagnosis on stress, and therapeutic strategies for neurodegenerative diseases with a special focus on stress reduction. Neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's Disease showed an acceleration in disease progression and a worsening of symptoms under stress. Some therapies (e.g., yoga, meditation) focused on reducing stress showed beneficial effects against neurodegeneration. Nevertheless, more studies are necessary in order to completely understand the implications of stress in neurodegeneration and the usefulness of stress reduction in the treatment thereof.

Frontrunner in Translation: Progressive Supranuclear Palsy

Progressive supranuclear palsy (PSP) is a four-repeat tau proteinopathy. Abnormal tau deposition is not unique for PSP and is the basic pathologic finding in some other neurodegenerative disorders such as Alzheimer's disease (AD), age-related tauopathy, frontotemporal degeneration, corticobasal degeneration, and chronic traumatic encephalopathy. While AD research has mostly been focused on amyloid beta pathology until recently, PSP as a prototype of a primary tauopathy with high clinical-pathologic correlation and a rapid course is a crucial candidate for tau therapeutic research. Several novel approaches to slow disease progression are being developed. It is expected that the benefits of translational research in this disease will extend beyond the PSP population. This article reviews advances in the diagnosis, epidemiology, pathology, hypothesized etiopathogenesis, and biomarkers and disease-modifying therapeutic approaches of PSP that is leading it to become a frontrunner in translation.