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OBJECTIVE To determine the effects of low-dose oral lithium on the neuropsychological performance of individuals diagnosed with HIV-associated neurocognitive impairment. DESIGN AND METHODS The project was a single-arm, open-label, 12-week pilot study at a university-based tertiary care center. The participants were adults who had been diagnosed with HIV-associated neurocognitive impairment and had been on stable antiretroviral therapy for at least 12 weeks. Conditions that could affect cognition, worsen adherence to study procedures, or increase the risk of lithium adverse reactions were excluded. Twenty-one individuals were screened and eight were enrolled, all of whom completed the study. Oral lithium was initiated at 300 mg daily and was titrated to maintain 12-h trough concentrations between 0.4 and 0.8 mEq/l. Global neuropsychological performance was assessed by the global deficit score. RESULTS At baseline, all participants had impaired neuropsychological performance and most had reduced CD4 cell counts (median 292 cells/microl), and HIV RNA levels in plasma below 400 copies/mL (seven of eight). Titrated lithium doses ranged between 600 and 1200 mg/day. Performance improved in all eight individuals after 12 weeks, and became unimpaired in six. The study treatment was well tolerated with no grade 3 or 4 adverse events and no premature discontinuations. CONCLUSIONS Lithium resulted in improved neuropsychological performance in antiretroviral-treated, impaired individuals in this small, open-label study. Based on published in vitro data, lithium may exert this effect by inhibiting neuronal glycogen synthase kinase-3beta.

HIV-1 often invades the CNS during primary infection, eventually resulting in neurological disorders in up to 50% of untreated patients. The CNS is a distinct viral reservoir, differing from peripheral tissues in immunological surveillance, target cell characteristics and antiretroviral penetration. Neurotropic HIV-1 likely develops distinct genotypic characteristics in response to this unique selective environment. We sought to catalogue the genetic features of CNS-derived HIV-1 by analysing 456 clonal RNA sequences of the C2-V3 env subregion generated from CSF and plasma of 18 chronically infected individuals. Neuropsychological performance of all subjects was evaluated and summarized as a global deficit score. A battery of phylogenetic, statistical and machine learning tools was applied to these data to identify genetic features associated with HIV-1 neurotropism and neurovirulence. Eleven of 18 individuals exhibited significant viral compartmentalization between blood and CSF (P < 0.01, Slatkin-Maddison test). A CSF-specific genetic signature was identified, comprising positions 9, 13 and 19 of the V3 loop. The residue at position 5 of the V3 loop was highly correlated with neurocognitive deficit (P < 0.0025, Fisher's exact test). Antibody-mediated HIV-1 neutralizing activity was significantly reduced in CSF with respect to autologous blood plasma (P < 0.042, Student's t-test). Accordingly, CSF-derived sequences exhibited constrained diversity and contained fewer glycosylated and positively selected sites. Our results suggest that there are several genetic features that distinguish CSF- and plasma-derived HIV-1 populations, probably reflecting altered cellular entry requirements and decreased immune pressure in the CNS. Furthermore, neurological impairment may be influenced by mutations within the viral V3 loop sequence.

The benefits of combination antiretroviral therapy (ART) for HIV cognitive disorders vary substantially between individuals. This study evaluated whether cerebrospinal fluid (CSF) drug penetration and CSF virological suppression influence the extent of neuropsychological (NP) improvement during ART. Overall performance on a battery of NP tests administered at baseline and follow-up (median 15 weeks) was computed by using the global deficit score (GDS) methods in 31 cognitively impaired, HIV-infected individuals who began new ART regimens. Virological suppression (attaining undetectable viral load by RT-PCR at follow-up) was assessed separately for plasma and CSF. Subjects on regimens containing greater numbers of CSF-penetrating drugs showed significantly greater reduction in CSF viral load. Subjects attaining CSF virological suppression demonstrated greater GDS improvement than those who did not (median GDS change, 0.62 vs 0.23; p = 0.01). A similar trend for plasma did not reach statistical significance (p = 0.053). NP improvement was greater in ART-naive versus treatment-experienced subjects. In a multivariate model (overall p = 0.0008), significant, independent predictors of GDS reduction were CSF HIV RNA suppression, baseline antiretroviral history, and their interaction. Including CSF-penetrating drugs in the ART regimen and monitoring CSF viral load may be indicated for individuals with HIV-associated cognitive impairment.

CCR2 is a minor coreceptor for human immune deficiency virus-1 (HIV-1) and its impact on HIV-1-related neuropsychological impairment (NPI) remains unknown. We studied the impact of CCR2-V64I polymorphisms on the development of NPI in 121 HIV-1 patients. The CCR2-64-I allele was associated with rate of progression to NPI when measured from the first study visit (Log Rank p=0.01) or from the estimated time of seroconversion (p=0.02). CCR2-V64I was not associated with plasma or CSF HIV-1 RNA load, suggesting that the impact of CCR2 on neuropathogenesis may involve alterations in inflammatory responses within the CNS rather than a direct impact on viral entry or replication.

Background Increased expression of monocyte chemoattractant protein type 1 (MCP-1) is associated with HIV CNS disease. This study evaluated the temporal relationships between MCP-1 expression and HIV replication in the CNS. Methods MCP-1 and HIV viral load (VL) were measured in serially obtained samples of plasma and cerebrospinal fluid (CSF) in subjects either interrupting (TI) or starting (TS) antiretroviral therapy. Results Following TI, plasma VL rebounded first, followed by increases in CSF MCP-1, which immediately preceded or coincided with a rebound of CSF VL. Conclusion The close temporal relationship of the increase of MCP-1 and CSF VL suggests that they are co-regulated, or that one is a stimulus for the other.

Background Neuropsychological (NP) impairment is a relatively common sequela in human immunodeficiency virus (HIV)–infected individuals with advanced disease. Early antecedents of NP dysfunction, however, remain poorly understood. Objective To determine whether early markers of immunocompetence and viral replication in individuals who have undergone seroconversion would be of prognostic value in identifying subjects who would become cognitively impaired. Methods Seventy-four subjects with estimable seroconversion dates and normal cognition at baseline (a median of 1 year after seroconversion) received NP and laboratory evaluations, including reverse transcription–polymerase chain reaction measurements of plasma (N = 74) and cerebrospinal fluid (n = 47) levels of HIV RNA. Subjects were followed up longitudinally, and were considered to have reached the end point if they became cognitively impaired. Results Using Kaplan-Meier estimates, the subgroups with the most rapid progression to NP impairment were (1) subjects with early reductions in CD4 counts ( P = .007) and (2) those with elevated plasma HIV RNA values (>4.5 log 10 copies/mL; P = .03) early after seroconversion. Using proportional hazards modeling, the highest-risk subjects had both CD4 counts less than 400 cells/µL and HIV RNA levels greater than 4.5 log 10 copies/mL (risk ratio, 6.0; P = .01). In most subjects (7/9 [78%]), NP impairment developed before an acquired immunodeficiency syndrome–defining illness. Conclusions Neurocognitive outcomes in HIV are strongly influenced by very early systemic virological and immunological events. Patients with high plasma levels of HIV RNA and low CD4 counts early after infection should be aggressively treated to prevent immunological decline and NP deterioration.

Abuse of methamphetamine (METH) is a frequent comorbidity among individuals infected with human immunodeficiency virus (HIV) type 1. In cell cultures and animal models, METH accelerates retroviral replication. To determine whether METH increases HIV replication in humans, we evaluated HIV loads in HIV-positive METH users and nonusers. We studied 3 groups: Tox+, active METH use and positive urine toxicology results; METH(+)Tox-, previous METH dependence/abuse and negative urine toxicology results; METH(-)Tox-, no METH dependence/abuse and negative urine toxicology results. Tox+ subjects' plasma virus loads were significantly higher than METH(+)Tox- and METH(-)Tox- subjects'; cerebrospinal fluid virus loads showed a similar but nonsignificant trend. Stratification by use of highly active antiretroviral therapy (HAART) revealed that virus loads were higher only in those Tox+ subjects who reported receiving HAART. In contrast, abstinent former METH abusers (METH(+)Tox-) receiving HAART effectively suppressed viral replication. These data suggest that abstinence programs are a key component of effective treatment of HIV in METH-abusing populations.

A review of Kawasaki disease (KD)-like syndromes (KDLS) in patients with human immunodeficiency virus (HIV) raised the question whether vasculitis in children and KDLS in immunocompromised adults might be etiologically related. We describe a 42-year-old white man with AIDS and Kaposi sarcoma who presented with KDLS, which was diagnosed on the basis of clinical criteria for KD. Analysis of a conjunctival tissue sample revealed endothelial cell damage with fibrin deposition and infiltration of immunoglobulin A-secreting plasma cells.

Background If cerebrospinal fluid (CSF) human immunodeficiency virus (HIV) RNA levels are elevated before the development of neuropsychological (NP) impairment, such an observation would support prospective monitoring of CSF HIV RNA levels as well as therapeutic interventions designed to lower CSF HIV levels. Objective To determine whether increased CSF HIV RNA levels at an earlier time predict subsequent progression to NP impairment in HIV-infected subjects. Methods We examined 139 subjects in a prospective cohort study. Comprehensive NP, neuromedical, and laboratory evaluations were performed at initial and follow-up visits at least 6 months apart. Human immunodeficiency virus RNA levels in plasma and CSF were measured with a commercially available, polymerase chain reaction–based assay. To assess the robustness of our findings, we analyzed changes in NP performance over time in 2 ways. First, we used masked clinical ratings of global NP performance to identify individuals who were initially NP normal, and then determined, in a similarly blinded fashion, which of these subjects subsequently became NP impaired. Second, in a separate analysis, we assessed change in subjects' raw scores on each of a series of NP test measures between baseline and follow-up. Results Among subjects who were not impaired at the initial visit, higher levels of HIV RNA in CSF significantly predicted progression to global NP impairment at the follow-up evaluation. Cerebrospinal fluid HIV RNA levels outperformed other clinical and laboratory measures in predicting progression to NP impairment. Higher CSF HIV RNA levels were associated with worsening performance on tests of attention, learning, and motor function. Conclusion Because elevated CSF HIV RNA levels (≥200 copies/mL) predict subsequent progression to NP impairment, monitoring of CSF viral load and therapy to reduce CSF HIV RNA levels may be clinically warranted, even if impairment is not identified at the time of lumbar puncture.

Previous studies of HIV-associated neurocognitive disease (HAND) have focused on the role of monocytes/macrophages. Having observed that high CD8 levels are a risk factor for HAND and hypothesizing that cerebrospinal fluid (CSF) could be a portal of entry for activated CD8 T-cells, we investigated cytokine responses by CSF T-cells. HIV+ participants with and without HAND were treated with CNS-penetrating anti-retroviral agents. CSF cells and PBMCs were harvested before treatment and at 6 and 16 weeks post-treatment and assessed for intracellular expression of IL-2, IFNg and TNFa, in response to HIV antigens. Data were examined both longitudinally (16 subjects with 3 visits) and cross-sectionally (30 subjects, total 59 visits). Overall, CD4 and CD8 T-cells in the CSF were more likely to make all three cytokines than CD4 and CD8 T-cells in blood. Impairment was associated with higher levels of constitutive and HIV-induced IFNg (p = .04) and TNFa (p = .05) expression by CD8 T-cells in the CSF. While higher levels of HIV RNA in CSF suppressed CD8 cytokine expression in unimpaired subjects, impaired subjects persisted with high cytokine expression regardless of RNA levels (p = .04). In addition to identifying a novel mechanism of HIV pathogenesis, these findings validate viral suppression in both CSF and the periphery as an important treatment goal for HAND, but also suggest that modulation of the CD8 T-cell response may be required.

Objective To evaluate whether penetration of a combination regimen into the central nervous system (CNS), as estimated by the CNS Penetration-Effectiveness (CPE) rank, is associated with lower cerebrospinal fluid (CSF) viral load. Design Data were analyzed from 467 participants who were human immunodeficiency virus (HIV) seropositive and who reported antiretroviral (ARV) drug use. Individual ARV drugs were assigned a penetration rank of 0 (low), 0.5 (intermediate), or 1 (high) based on their chemical properties, concentrations in CSF, and/or effectiveness in the CNS in clinical studies. The CPE rank was calculated by summing the individual penetration ranks for each ARV in the regimen. Results The median CPE rank was 1.5 (interquartile range, 1-2). Lower CPE ranks correlated with higher CSF viral loads. Ranks less than 2 were associated with an 88% increase in the odds of detectable CSF viral load. In multivariate regression, lower CPE ranks were associated with detectable CSF viral loads even after adjusting for total number of ARV drugs, ARV drug adherence, plasma viral load, duration and type of the current regimen, and CD4 count. Conclusions Poorer penetration of ARV drugs into the CNS appears to allow continued HIV replication in the CNS as indicated by higher CSF HIV viral loads. Because inhibition of HIV replication in the CNS is probably critical in treating patients who have HIV-associated neurocognitive disorders, ARV treatment strategies that account for CNS penetration should be considered in consensus treatment guidelines and validated in clinical studies.

Aged (>50 years old) human immunodeficiency virus (HIV) patients are the fastest-growing segment of the HIV-infected population in the USA and despite antiretroviral therapy, HIV-associated neurocognitive disorder (HAND) prevalence has increased or remained the same among this group. Autophagy is an intracellular clearance pathway for aggregated proteins and aged organelles; dysregulation of autophagy is implicated in the pathogenesis of Parkinson's disease, Alzheimer's disease, and HAND. Here, we hypothesized that dysregulated autophagy may contribute to aging-related neuropathology in HIV-infected individuals. To explore this possibility, we surveyed autophagy marker levels in postmortem brain samples from a cohort of well-characterized 50 years old (aged) HIV+ and HIV encephalitis (HIVE) patients. Detailed clinical and neuropathological data showed the young and aged HIVE patients had higher viral load, increased neuroinflammation and elevated neurodegeneration; however, aged HIVE postmortem brain tissues showed the most severe neurodegenerative pathology. Interestingly, young HIVE patients displayed an increase in beclin-1, cathepsin-D and light chain (LC)3, but these autophagy markers were reduced in aged HIVE cases compared to age-matched HIV+ donors. Similar alterations in autophagy markers were observed in aged gp120 transgenic (tg) mice; beclin-1 and LC3 were decreased in aged gp120 tg mice while mTor levels were increased. Lentivirus-mediated beclin-1 gene transfer, that is known to activate autophagy pathways, increased beclin-1, LC3, and microtubule-associated protein 2 expression while reducing glial fibrillary acidic protein and Iba1 expression in aged gp120 tg mice. These data indicate differential alterations in the autophagy pathway in young versus aged HIVE patients and that autophagy reactivation may ameliorate the neurodegenerative phenotype in these patients.

Chemokines influence HIV neuropathogenesis by affecting the HIV life cycle, trafficking of macrophages into the nervous system, glial activation, and neuronal signaling and repair processes; however, knowledge of their relationship to in vivo measures of cerebral injury is limited. The primary objective of this study was to determine the relationship between a panel of chemokines in cerebrospinal fluid (CSF) and cerebral metabolites measured by proton magnetic resonance spectroscopy (MRS) in a cohort of HIV-infected individuals. One hundred seventy-one stored CSF specimens were assayed from HIV-infected individuals who were enrolled in two ACTG studies that evaluated the relationship between neuropsychological performance and cerebral metabolites. Concentrations of six chemokines (fractalkine, IL-8, IP-10, MCP-1, MIP-1β, and SDF-1) were measured and compared with cerebral metabolites individually and as composite neuronal, basal ganglia, and inflammatory patterns. IP-10 and MCP-1 were the chemokines most strongly associated with individual cerebral metabolites. Specifically, (1) higher IP-10 levels correlated with lower N-acetyl aspartate (NAA)/creatine (Cr) ratios in the frontal white matter and higher MI/Cr ratios in all three brain regions considered and (2) higher MCP-1 levels correlated with lower NAA/Cr ratios in frontal white matter and the parietal cortex. IP-10, MCP-1, and IL-8 had the strongest associations with patterns of cerebral metabolites. In particular, higher levels of IP-10 correlated with lower neuronal pattern scores and higher basal ganglia and inflammatory pattern scores, the same pattern which has been associated with HIV-associated neurocognitive disorders (HAND). Subgroup analysis indicated that the effects of IP-10 and IL-8 were influenced by effective antiretroviral therapy and that memantine treatment may mitigate the neuronal effects of IP-10. This study supports the role of chemokines in HAND and the validity of MRS as an assessment tool. In particular, the findings identify relationships between the immune response—particularly an interferon-inducible chemokine, IP-10—and cerebral metabolites and suggest that antiretroviral therapy and memantine modify the impact of the immune response on neurons.

HIV-infected individuals are at risk for a spectrum of neurocognitive disorders. Research performed in developed and resource-limited settings indicates that over half of HIV-infected individuals may have neurocognitive impairment of at least mild severity. An important issue complicating the pathogenesis of these disorders is the coexistence of multiple neurotoxic conditions. Two important comorbidities are co-infection with Hepatitis C Virus (HCV) and use of stimulants, such as methamphetamine (MA).