Increased frequency of alpha-synuclein in the substantia nigra in human immunodeficiency virus infection

TitleIncreased frequency of alpha-synuclein in the substantia nigra in human immunodeficiency virus infection
Publication TypeJournal Article
Year of Publication2009
AuthorsKhanlou, N, Moore, D, Chana, G, Cherner, M, Lazzaretto, D, Dawes, S, Grant, I, Masliah, E, Everall, I
JournalJournal of Neurovirology
Date Published2009
KeywordsAge Factors, Aged, alpha-Synuclein, Amyloid beta-Protein, Biological Markers, Female, HIV, HIV Infections, Humans, Immunohistochemistry, Internal, Male, Middle Aged, Neurodegenerative Diseases, Substantia Nigra, Up-Regulation

The frequency of neurodegenerative markers among long surviving human immunodeficiency virus (HIV)-infected individuals is unknown, therefore, the present study investigated the frequency of alpha-synuclein, beta-amyloid, and HIV-associated brain pathology in the brains of older HIV-infected individuals. We examined the substantia nigra of 73 clinically well-characterized HIV-infected individuals aged 50 to 76 years from the National NeuroAIDS Tissue Consortium. We also examined the frontal and temporal cortical regions of a subset of 36 individuals. Neuritic alpha-synuclein expression was found in 16% (12/73) of the substantia nigra of the HIV+cases and none of the older control cases (0/18). beta-Amyloid deposits were prevalent and found in nearly all of the HIV+cases (35/36). Despite these increases of degenerative pathology, HIV-associated brain pathology was present in only 10% of cases. Among older HIV+adults, HIV-associated brain pathology does not appear elevated; however, the frequency of both alpha-synuclein and beta-amyloid is higher than that found in older healthy persons. The increased prevalence of alpha-synuclein and beta-amyloid in the brains of older HIV-infected individuals may predict an increased risk of developing neurodegenerative disease.