Potential Mechanism for HIV-Associated Depression: Upregulation of Serotonin Transporters in SIV-Infected Macaques Detected by 11C-DASB PET.

Increased incidence of depression in HIV+ patients is associated with lower adherence to treatment and increased morbidity/mortality. One possible underlying pathophysiology is serotonergic dysfunction. In this study, we used an animal model of HIV, the SIV-infected macaque, to longitudinally image serotonin transporter (SERT) expression before and after inoculation, using 11C-DASB (SERT ligand) PET imaging.

Neuroinflammatory Changes in Relation to Cerebrospinal Fluid Viral Load in Simian Immunodeficiency Virus Encephalitis.

The exact cause of neurocognitive dysfunction in HIV-positive patients despite successful control of the infection in the periphery is not completely understood. One suggested mechanism is a vicious cycle of microglial activation and release of proinflammatory chemokines/cytokines that eventually leads to neuronal loss and dysfunction. However, the exact role of microglial activation in the earliest stages of the infection with high cerebrospinal fluid (CSF) viral loads (VL) is unclear.

MR brain volumetric measurements are predictive of neurobehavioral impairment in the HIV-1 transgenic rat.

Introduction: HIV infection is known to be associated with brain volume loss, even in optimally treated patients. In this study, we assessed whether dynamic brain volume changes over time are predictive of neurobehavorial performance in the HIV-1 transgenic (Tg) rat, a model of treated HIV-positive patients.

Materials And Methods: Cross-sectional brain MRI imaging was first performed comparing Tg and wild type (WT) rats at 3 and 19 months of age.

Cross-sectional and longitudinal small animal PET shows pre and post-synaptic striatal dopaminergic deficits in an animal model of HIV.

Introduction: In vivo imaging biomarkers of various HIV neuropathologies, including dopaminergic dysfunction, are still lacking. Towards developing dopaminergic biomarkers of brain involvement in HIV, we assessed the pre and postsynaptic components of the dopaminergic system in the HIV-1 transgenic rat (Tg), a well-characterized model of treated HIV+ patients, using small-animal PET imaging.

Methods: Fifteen to 18 month-old Tg and wild type (WT) rats were imaged with both [18F]-FP-CMT, a dopamine transporter (DAT) ligand (n=16), and [18F]-Fallypride, a D2/D3 dopamine receptor (D2/D3DR) ligand (n=16).

Neurobehavioral Abnormalities in the HIV-1 Transgenic Rat Do Not Correspond to Neuronal Hypometabolism on 18F-FDG-PET.

Motor and behavioral abnormalities are common presentations among individuals with HIV-1 associated neurocognitive disorders (HAND). We investigated whether longitudinal motor and behavioral performance in the HIV-1 transgenic rat (Tg), a commonly used neuro-HIV model, corresponded to in vivo neuronal death/dysfunction, by using rotarod and open field testing in parallel to [18F] 2-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET). We demonstrated that age-matched non-Tg wild type (WT) rats outperformed the HIV-1 Tg rats at most time points on rotarod testing.