title: Plasma cytokine levels are related to brain volumes in HIV-infected individuals.
abstract: HIV-infected individuals frequently exhibit brain dysfunction despite antiretroviral treatment. The neuropathological mechanisms underlying these abnormalities remain unclear, pointing to the importance of identifying biomarkers sensitive to brain dysfunction. We examined 74 medically stable HIV-infected individuals using T1-weighted MRI. Volumes of the cortical grey matter (GM), white matter (WM), caudate, putamen, globus pallidus, thalamus, hippocampus, amygdala, and ventricles were derived using automated parcellation. A panel of plasma cytokines was measured using multiplexed bead array immunoassay. A model selection algorithm was used to select the combination of clinical and cytokine markers that best predicted each brain volumetric measure in a series of linear regression models. Higher CD4 nadir, shorter HIV infection duration, and antiretroviral treatment were significantly related to higher volumes of the putamen, thalamus, hippocampus, and WM. Older age was related to lower volumes in most brain regions and higher ventricular volume. Higher IFN-γ, MCP-1, and TNF-α were related to higher volumes of the putamen, pallidum, amygdala, GM, and WM. Higher IL-1β, IL-6, IL-16, IL-18, IP-10, MIP-1β, and SDF-1α were related to lower volumes of the putamen, pallidum, thalamus, hippocampus, amygdala, GM, and WM; and higher ventricular volume. The current findings provide evidence linking smaller brain volumes to HIV disease history, antiretroviral treatment, and advanced age. Cytokine markers, especially IL-6 and IL-16, showed robust association with brain volumes even after accounting for other clinical variables, demonstrating their utility in examining the mechanisms of HIV-associated brain abnormalities.
authors.affiliation: Department of Psychiatry, University of California, San Diego, USA.
authors.forename: Assawin
authors.initials: A
authors.lastname: Gongvatana
authors.forename: Stephen
authors.initials: S
authors.lastname: Correia
authors.forename: Shira
authors.initials: S
authors.lastname: Dunsiger
authors.forename: Lynne
authors.initials: L
authors.lastname: Gauthier
authors.forename: Kathryn N
authors.initials: KN
authors.lastname: Devlin
authors.forename: Skye
authors.initials: S
authors.lastname: Ross
authors.forename: Bradford
authors.initials: B
authors.lastname: Navia
authors.forename: Karen T
authors.initials: KT
authors.lastname: Tashima
authors.forename: Suzanne
authors.initials: S
authors.lastname: DeLaMonte
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Cohen
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001921:Brain / Q000378:metabolism* / Q000473:pathology*; D016207:Cytokines / Q000097:blood*; D005260:Female; D015658:HIV Infections / Q000097:blood* / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D055815:Young Adult
chemical_list: D015415:Biomarkers; D016207:Cytokines