Neurocognitive implications of cannabidiol (CBD) while aging with HIV - PROJECT SUMMARY The success of combined antiretroviral therapy (cART) has drastically improved the life expectancy of people living with HIV. This has resulted in the clinical observations of significant age-related neurocognitive complications among the population aging with HIV. HIV-associated inflammation has been implicated in premature aging and increased risk of age-associated comorbidities even in cART-treated individuals. Currently, people living with HIV are using cannabis, for recreational or medical purposes, at higher rates than the general population. However, cannabinoids in the context of HIV and aging remain preclinically unexplored. As the use of medical cannabis among older HIV individuals continues to rise, there is an urgent need to investigate the consequences of cannabinoids during aging with HIV. The goal of this proposal is to unravel the beneficial versus the detrimental effects of cannabinoids on HIV and HIV-induced neurocognitive deficits in aged mice. It has been shown that cannabidiol (CBD) improves both spatial and recognition memory and decreases anxiety in a mouse model of Alzheimer’s disease, suggesting its therapeutic potential for age‐related dementia. Therefore, we hypothesize that exposure to CBD will modulate neuroinflammation and cognitive deficits in mice that aged with HIV. To test this hypothesis, C57BL/6J male and female adult mice (at 16-months old) will be infected with the mouse-tropic HIV, EcoHIV. After 8 weeks (at 18-months old), a subset of EcoHIV-infected mice will be exposed to CBD alone, antiretrovirals alone, and concomitant CBD and antiretrovirals for 21 days. In Specific Aim 1, we posit that CBD will modulate HIV- and age-associated cognitive deficits, specifically memory, and learning functions, measured by the novel object recognition test and the Y-maze behavioral test. In Specific Aim 2, we posit that CBD exposure will modulate neuroinflammation, glial phenotypes, and cellular senescence in postmortem brain tissue of EcoHIV-infected and aged mice recovered in Specific Aim 1. The experiments described in this proposal will allow us to determine the molecular mechanisms that could mediate the consequences of cannabinoids exposure in the HIV-infected aged brain. The ultimate goal of this project is to identify a potential therapeutic target that could reduce age-related neurodegenerative deficits associated with chronic HIV infection.