PROJECT SUMMARY/ABSTRACT
Human immunodeficiency virus (HIV) infections are dramatically climbing in adolescents, who are infected
during a time of critical brain development characterized by significant myelination. Adolescents may therefore
be particularly vulnerable to the white matter pathologies closely linked to HIV-associated neurocognitive
disorders (HAND), which affect 30-50% of people living with HIV. Understanding the mechanisms resulting in
HIV-related white matter deficits will be key in the development of therapies to promote myelin integrity and
repair, which may greatly improve neurological function. One important factor predictive of both cognitive decline
in HIV and a lack of myelin is altered brain lipid metabolism. Myelin is highly enriched in cholesterol and lipids,
and both oligodendrocytes, the myelin-producing glial cells of the central nervous system, and astrocytes must
synthesize large quantities of cholesterol and lipids for successful myelination to occur. Based on published and
preliminary data, I hypothesize that glial lipid biosynthesis and transport essential for adolescent
myelination are dysregulated by HIV or DTG/TDF/FTC antiretroviral therapy (ART), making lipid metabolism
a potential therapeutic target for improving white matter integrity in adolescents living with HIV. To address this
hypothesis, I will determine how HIV and ART affect 1) oligodendroglial lipid metabolism and resulting myelin
lipid composition and adolescent myelination, and 2) astroglial lipid metabolism and release and its impact on
myelin formation. Successful completion of the proposed aims will reveal whether HIV or ART affect lipid
metabolism in either oligodendrocytes and/or astrocytes and whether this is detrimental to adolescent
myelination. Results from the proposed studies will directly advance the mission of the NIMH by
transforming our understanding of mechanisms of white matter pathology in adolescent HIV/HAND,
revealing potential therapeutic targets for prevention of and recovery from HIV-related neuropathology.