HIV-associated deficits in action (verb) generation may reflect astrocytosis

• Published in: Journal of clinical and experimental neuropsychology Vol. 32; no. 5; pp. 522 - 527
• Main Authors: Woods, Steven Paul, Iudicello, Jennifer E., Dawson, Matthew S., Weber, Erica, Grant, Igor, Letendre, Scott L., The HIV Neurobehavioral Research Center (HNRC) Group
• Format: Journal Article
• Language: English
• Published: Hove Taylor & Francis Group 01.06.2010; Psychology Press
• Subjects: Adult; Adult and adolescent clinical studies; antiretroviral therapy; Astrocytes; Biological and medical sciences; biomarkers; CD4 Antigens - metabolism; Cell activation; Cerebrospinal fluid; Chemokine CCL2 - metabolism; Chemokine CXCL10 - metabolism; Cognitive ability; Cognitive processes; Data processing; Executive function; Executive Function - physiology; Female; Frontal lobe; Gliosis; Gliosis - etiology; Gliosis - virology; HIV Infections - complications; Human immunodeficiency virus; Human viral diseases; Humans; Immunodeficiencies; Immunodeficiencies. Immunoglobulinopathies; Immunopathology; Infection; Infectious diseases; Inflammation; Language; Language Disorders - etiology; Language Tests; Macrophages; Male; Medical sciences; Middle Aged; Nerve Growth Factors - metabolism; Neuroprotection; Neuropsychological Tests; Organic mental disorders. Neuropsychology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; S100 Calcium Binding Protein beta Subunit; S100 Proteins - metabolism; Semantics; Statistics, Nonparametric; tau Proteins - metabolism; Verbal Behavior - physiology; Verbal fluency; Verbs; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids; Human; Immunopathology; Verbal fluency; Frontal lobe; Central nervous system; Retroviridae; Biological marker; AIDS; Cognition; Verbal production; Immune deficiency; Lentivirus; Encephalon; Infection; Virus; Cognitive processes; Language; Viral disease; Verb; Human immunodeficiency virus; Verbs
• ISSN: 1380-3395; 1744-411X
• DOI: 10.1080/13803390903264130

Commensurate with the hypothesized neural dissociation between verb and noun generation, research in HIV infection shows that, relative to noun fluency, action (verb) fluency is disproportionately impaired, more strongly related to executive dysfunction, and more sensitive to declines in everyday functioning. However, whether the neurobiological correlates of HIV-associated deficits in verb and noun generation are separable have not heretofore been investigated. The present study examined the biomarker correlates of action and noun fluency in 74 participants with HIV infection. Biomarkers of viral burden, neuroaxonal damage, macrophage activation, neuroprotection, inflammation, and astrocytosis were measured in plasma and cerebrospinal fluid (CSF). Deficits in action, but not noun generation, were significantly associated with higher CSF levels of S100β, a marker of astrocyte activation, even after controlling for antiretroviral therapy, current immune compromise, and general cognitive impairment. Concurrent validity for the frontal systems hypothesis of verb generation was provided by post hoc analyses demonstrating that S100β was also associated with measures of executive functions, but not semantic memory or psychomotor speed. Overall, these findings suggest that HIV-associated impairment in action fluency, and executive dysfunction more generally, may reflect astrocytosis (i.e., elevated S100β). Complementing the literature in HIV and other clinical populations with frontal systems involvement, these data also support the possible neurobiological dissociation of noun and verb generation.