AccScience Publishing / AN / Volume 2 / Issue 1 / DOI: 10.36922/an.326
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Alpha-synuclein at the interface between depression and neurodegeneration: Evidence from epidemiological and genetic data

Ravi Philip Rajkumar*
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1 Department of Psychiatry, Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, India
Advanced Neurology 2023, 2(1), 326
Submitted: 16 January 2023 | Accepted: 21 February 2023 | Published: 6 March 2023
© 2023 by the Author(s). Licensee AccScience Publishing, Singapore, Singapore. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

Parkinson’s disease (PD) and Alzheimer’s disease (AlzD) are the two most common neurodegenerative disorders. Although these two disorders differ in terms of their underlying pathophysiology, clinical features, and course, there is a certain degree of overlap between them. This overlap may be partly related to alpha-synuclein (α-synuclein)-mediated neuropathological changes. Recent evidence has found that depression is associated with increased subsequent risk of both these neurological disorders and α-synuclein may also play a pathogenic role in depression. In the current study, epidemiological, population genetic, and environmental exposure data were examined in relation to the estimated prevalence of depressive disorders, PD, and AlzD using a cross-sectional, country-level analysis. The results showed a significant relationship between depressive disorders and neurodegenerative disorders, a possible shared genetic vulnerability related to the functional polymorphisms of SNCA gene, and potential gene-environment interactions involving fine particulate matter pollution. The significance of these results is discussed in light of existing translational, clinical, and epidemiological research on the links between these disorders.

Major depression
Parkinson’s disease

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Conflict of interest
The author declares that he has no competing interests.
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