Alzheimer-type cerebral amyloidosis in the context of HIV infection: implications for a proposed new treatment approach

Reverse transcriptase inhibitors (RTIs) are currently broadly prescribed for the treatment of HIV infection but are also thought to prevent Alzheimer's Disease (AD) progression by protecting against amyloidosis. Our study evaluates the hypothesis that reverse transcriptase inhibitors protect against Alzheimer-type brain amyloidogenesis in the context of HIV infection. We compiled a case series of participants from a prospective study of the neurological consequences of HIV infection at the HIV Neurobehavioral Research Program (HNRP) who had serial neuropsychological and neurological assessments and were on RTIs. Two participants had gross and microscopic examination and immunohistochemistry of the brain at autopsy; one was assessed clinically for Alzheimer's Disease by cerebrospinal fluid (CSF) analysis of phosphorylated-Tau, Total-Tau and Aβ42. Additionally, a larger cohort of autopsied individuals was evaluated for presence of amyloid plaques, Tau, and related pathologies. Three older, virally suppressed individuals with HIV who had long-term treatment with RTIs were included in analyses. Two cases demonstrated substantial cerebral amyloid deposition at autopsy. The third case met clinical criteria for AD based on a typical clinical course and CSF biomarker profile. In the larger cohort of autopsied individuals, the prevalence of cerebral amyloidosis among people with HIV (PWH) was greater for those on RTIs. Our study showed that long-term RTI therapy did not protect against Alzheimer-type brain amyloidogenesis in the context of HIV infection in these patients. Given the known toxicities of RTIs, it is premature to recommend them to individuals at risk or with Alzheimer's disease who do not have HIV infection.

Subacute myoclonic measles encephalitis - An opportunistic HIV-associated infection

Introduction

An unusual cluster of myoclonic epilepsy was observed in a Romanian pediatric HIV cohort concurrent with measles outbreaks. We describe this particular form of subacute measles encephalitis (SME) in a group of HIV-infected children and adolescents with severe immunosuppression.

Methods

This is a single-center study, starting in 1997 and covering 4 measles outbreaks in Romania. The presumptive diagnosis of subacute myoclonic measles encephalitis (SMME) was based on: (1) epidemiological data, previous measles episode or presumed contact with measles virus (MV), (2) clinical presentation with initial localized myoclonic jerks with rapid extension and subsequent motor deficit with preserved mental status, and (3) neuroimaging studies revealing cortical gray matter lesions. Definitive diagnosis was based on a neuropathological exam and immunohistochemistry of brain tissues, and measles RNA detection in the cerebrospinal fluid (CSF).

Results

Thirty-six patients were diagnosed with a particular form of SME during consecutive measles outbreaks in Romania: 1996-1998 (22); 2005-2008 (12); 2010-2011 (1) and 2016-2018 (1). Most children were born in the late 80s and had parenterally acquired HIV infection in early childhood. Before the episode of SMME, 11 patients had confirmed measles, while the rest, without typical rash, had a respiratory tract infection and/or presumed previous measles contact. In all patients, the clinical onset was sudden, with unilateral myoclonus. MRI findings revealed mainly focal cortical gray matter lesions. Neurologic symptoms progressed rapidly to coma and death in most patients. Three patients survived SMME, they had higher CD4 count at onset, slower progression of neurological symptoms, and benefit of immune recovery with cART. Immunocytochemistry studies revealed MV in the brain with a pattern suggesting an ascending viral neural infection. MV was isolated from CSF in 7 out of 8 patients. Sequence analysis of MV RNA from both nasopharyngeal swabs and CSF was available for one patient with similar N-450 strain characteristics.

Conclusion

During an outbreak of measles, neurological manifestations, especially myoclonus in immunosuppressed patients, can be related to measles even in the absence of an acute episode. This particular form of subacute myoclonic measles encephalitis is an opportunistic fatal disease. Immune recovery due to effective antiretroviral treatment might increase survival.

Immuno-inflammatory changes across phases of early psychosis: The impact of antipsychotic medication and stage of illness

INTRODUCTION

Research examining the role of inflammation in psychosis has produced inconsistent results. Variables that influence inflammation, including antipsychotic medication, are inconsistently controlled across studies and variation of inflammatory analytes across stages of psychosis may also influence findings. The purpose of this study was to assess for evidence of immuno-inflammatory dysregulation across the stages of early psychosis. We examined a immuno-inflammatory analytes in subjects at clinical high risk (CHR) for developing a psychotic disorder, antipsychotic-naïve (-n) and antipsychotic treated (-a) subjects in their first episode of psychosis (FEP), and healthy control (HC) subjects.

METHODS

A total of 11 subjects at CHR, 50 subjects within their FEP (40 FEP-n, 10 FEP-a), and 10 HC subjects were recruited from early psychosis programs in San Diego and Mexico City. Plasma was collected for biomarker assay.

RESULTS

Immuno-inflammatory analytes significantly differed between groups: Interferon-gamma (IFN-γ), Interleukin-10 (IL-10), Eotaxin-1, Interferon Gamma-Induced Protein-10 (IP-10), Monocyte Chemotactic Protein-1 (MCP-1), Macrophage-Derived Chemokine (MDC), Macrophage Inflammatory Protein-1 beta (MIP-1β), Thymus and Activation Regulated Chemokine (TARC), and Brain Derived Neurotropic Factor (BDNF). Post-hoc analyses revealed an overall pattern of higher levels of IL-10, MCP-1, MIP-1β, TARC, and BDNF in CHR as compared to FEP-a, FEP-n, and HC subjects.

CONCLUSIONS

Results reveal a profile of immuno-inflammatory dysregulation in early stages of psychosis prior to psychotic conversion and treatment with antipsychotic medication. The CHR phase of early psychosis may represent a period of increased immuno-inflammatory activation, but due to limited sample size, these results deserve replication in a well characterized early psychosis population.

Antiretroviral drug concentrations in brain tissue of adult decedents

OBJECTIVE

Determine concentrations of antiretroviral therapy (ART) drugs in the human brain.

DESIGN

Cohort study of persons with HIV who consented to antemortem assessment and postmortem autopsy.

METHODS

Eleven persons with HIV who were taking ART at the time of death and had detectable concentrations of at least one ART drug in intracardiac aspirate at autopsy were evaluated. Autopsies were performed within 24 h of death and brain tissue was stored at -80 °C. Concentrations of 11 ART drugs were measured in three brain regions (globus pallidus, cortical gray matter, white matter) by HPLC tandem mass spectrometry with a lower limit of quantification of 25 ng/ml.

RESULTS

Participants were mostly men (82%) with a mean age of 40.4 years. Drug concentrations in brain tissue were highly variable and exceeded published concentrations in cerebrospinal fluid for several drugs, including for tenofovir, efavirenz, and lopinavir. Drug concentrations correlated most strongly between cortical gray matter and globus pallidus (rho = 0.70) but less well between globus pallidus and white matter (rho = 0.43). Combining all drugs and brain regions (n = 89), higher drug concentrations in brain were associated with longer estimated duration of HIV infection (P = 0.015), lower HIV RNA in plasma (P = 0.0001), lower nadir CD4 T-cell count (P = 0.053), and worse neurocognitive performance (P = 0.017).

CONCLUSION

This is the first analysis of ART drug concentrations in human brain tissue. Concentrations of several drugs in this analysis were similar to published concentrations in cerebrospinal fluid but others exceeded published concentrations. The association between higher drug concentrations in the brain and worse neurocognitive performance may indicate ART neurotoxicity.

Beta amyloid levels in cerebrospinal fluid of HIV-infected people vary by exposure to antiretroviral therapy

BACKGROUND

HIV-associated neurocognitive disorders (HAND) persist despite the widespread implementation of combined antiretroviral therapy (ART). As people with HIV (PWH) age on ART regimens, the risk of age-related comorbidities, such as Alzheimer's disease may increase. However, questions remain as to whether HIV or ART will alter such risks. Beta amyloid (Aβ) and phosphorylated-tau (p-tau) proteins are associated with Alzheimer's disease and their levels are altered in the CSF of Alzheimer's disease cases.

METHODS

To better understand how these Alzheimer's disease-related markers are affected by HIV infection and ART, postmortem CSF collected from 70 well characterized HIV+ decedents was analyzed for Aβ1-42, Aβ1-40, and p-tau levels.

RESULTS

Aβ1-42 and Aβ1-40 CSF levels were higher in cases that were exposed to ART. Aβ1-42 and Aβ1-40 CSF levels were also higher in cases on protease inhibitors compared with those with no exposure to protease inhibitors. Aβ1-42 and Aβ1-40 levels in CSF were lowest in HIV+ cases with HIV-associated dementia (HAD) and levels were highest in those diagnosed with asymptomatic neurocognitive impairment (ANI) and minor neurocognitive disorder (MND). Aβ1-42 and Aβ1-40 were inversely related with p-tau levels in all cases, as previously reported.

CONCLUSION

These data suggest that ART exposure is associated with increased levels of Aβ1-42 and Aβ1-40 in the CSF. Also, HAD, but not ANI/MND diagnosis is associated with decreased levels of Aβ1-42 and Aβ1-40 in CSF, potentially suggesting impaired clearance. These data suggest that HIV infection and ART may impact pathogenic mechanisms involving Aβ1-42 and Aβ1-40, but not p-tau.

Neurocognitive Impairment in the Combined Antiretroviral Therapy Era in a Romanian Cohort of Young Adults with Chronic HIV Infection

HIV-associated neurocognitive disorders (HAND) continue to be reported even in patients with successful antiretroviral treatment. We investigated the prevalence of neurocognitive impairment and possible HIV-associated determinants of cognition in a Romanian cohort of young adults, parenterally infected with HIV during their first years of life. Two hundred fourteen treatment-experienced HIV-positive individuals [median age: 24 years, males: 48%, median duration on combined antiretroviral therapy (cART): 12 years] underwent standard immunologic and virological monitoring and antiretroviral resistance testing using pol gene sequencing in both plasma and, when available, cerebrospinal fluid (CSF) paired samples. Neurocognitive impairment was assessed using a comprehensive neuropsychological test battery, and a global deficit score (GDS) was calculated (cutoff ≥0.5). Cognitive impairment was detected in 35% of the study participants, without any association with sex, median age, CD4 cell count (actual or nadir), CSF and plasma viral load (actual or zenith), AIDS diagnosis, duration of HIV infection, and cART characteristics. Participants carrying resistant viruses tended to be more frequently cognitively impaired (p = 0.36), with a higher median GDS value (p = 0.06) compared with participants harboring wild-type HIV, although the figures did not reach statistical significance. No signs of virological compartmentalization were observed based on CSF versus plasma viral load and on the profile of pol sequences. A moderate rate of mild neurocognitive impairment is still present in young adults with chronic HIV infection acquired in early childhood despite successful cART, without any association with classic markers of HIV infection. New biomarkers reflecting persistent central nervous system inflammation and neuronal injury may be more relevant for the development of HAND.

Tenofovir disoproxil fumarate induces peripheral neuropathy and alters inflammation and mitochondrial biogenesis in the brains of mice

Mounting evidence suggests that antiretroviral therapy (ART) drugs may contribute to the prevalence of HIV-associated neurological dysfunction. The HIV envelope glycoprotein (gp120) is neurotoxic and has been linked to alterations in mitochondrial function and increased inflammatory gene expression, which are common neuropathological findings in HIV+ cases on ART with neurological disorders. Tenofovir disproxil fumarate (TDF) has been shown to affect neurogenesis in brains of mice and mitochondria in neurons. In this study, we hypothesized that TDF contributes to neurotoxicity by modulating mitochondrial biogenesis and inflammatory pathways. TDF administered to wild-type (wt) and GFAP-gp120 transgenic (tg) mice caused peripheral neuropathy, as indicated by nerve conduction slowing and thermal hyperalgesia. Conversely TDF protected gp120-tg mice from cognitive dysfunction. In the brains of wt and gp120-tg mice, TDF decreased expression of mitochondrial transcription factor A (TFAM). However, double immunolabelling revealed that TFAM was reduced in neurons and increased in astroglia in the hippocampi of TDF-treated wt and gp120-tg mice. TDF also increased expression of GFAP and decreased expression of IBA1 in the wt and gp120-tg mice. TDF increased tumor necrosis factor (TNF) α in wt mice. However, TDF reduced interleukin (IL) 1β and TNFα mRNA in gp120-tg mouse brains. Primary human astroglia were exposed to increasing doses of TDF for 24 hours and then analyzed for mitochondrial alterations and inflammatory gene expression. In astroglia, TDF caused a dose-dependent increase in oxygen consumption rate, extracellular acidification rate and spare respiratory capacity, changes consistent with increased metabolism. TDF also reduced IL-1β-mediated increases in IL-1β and TNFα mRNA. These data demonstrate that TDF causes peripheral neuropathy in mice and alterations in inflammatory signaling and mitochondrial activity in the brain.

Pathogenesis of age-related HIV neurodegeneration

People over the age of 50 are the fastest growing segment of the HIV-infected population in the USA. Although antiretroviral therapy has remarkable success controlling the systemic HIV infection, HIV-associated neurocognitive disorder (HAND) prevalence has increased or remained the same among this group, and cognitive deficits appear more severe in aged patients with HIV. The mechanisms of HAND in the aged population are not completely understood; a leading hypothesis is that aged individuals with HIV might be at higher risk of developing Alzheimer's disease (AD) or one of the AD-related dementias (ADRD). There are a number of mechanisms through which chronic HIV disease alone or in combination with antiretroviral therapy and other comorbidities (e.g., drug use, hepatitis C virus (HCV)) might be contributing to HAND in individuals over the age of 50 years, including (1) overlapping pathogenic mechanisms between HIV and aging (e.g., decreased proteostasis, DNA damage, chronic inflammation, epigenetics, vascular), which could lead to accelerated cellular aging and neurodegeneration and/or (2) by promoting pathways involved in AD/ADRD neuropathogenesis (e.g., triggering amyloid β, Tau, or α-synuclein accumulation). In this manuscript, we will review some of the potential common mechanisms involved and evidence in favor and against a role of AD/ADRD in HAND.

Plasma CXCL10 correlates with HAND in HIV-infected women

HIV-associated neurocognitive disorder (HAND) is characterized by chronic immune activation. We aimed to identify biomarkers associated with HAND and to investigate their association with cognitive function and sex, in a homogenous cohort of HIV-infected (HIV+) young adults, parenterally infected during early childhood. One hundred forty-four HIV+ Romanian participants (51% women) without major confounders underwent standardized neurocognitive and medical evaluation in a cross-sectional study. IFN-γ, IL-1β, IL-6, CCL2, CXCL8, CXCL10, and TNF-α were measured in plasma in all participants and in cerebrospinal fluid (CSF) in a subgroup of 56 study participants. Biomarkers were compared with neurocognitive outcomes, and the influence of sex and HIV disease biomarkers was assessed. In this cohort of young adults (median age of 24 years), the rate of neurocognitive impairment (NCI) was 36.1%. Median current CD4+ count was 479 cells/mm³ and 36.8% had detectable plasma viral load. Women had better HIV-associated overall status. In plasma, controlling for sex, higher levels of IL-6 and TNF-α were associated with NCI (p < 0.05). Plasma CXCL10 showed a significant interaction with sex (p = 0.02); higher values were associated with NCI in women only (p = 0.02). Individuals with undetectable viral load had significantly lower plasma CXCL10 (p < 0.001) and CCL2 (p = 0.02) levels, and CSF CXCL10 (p = 0.01), IL-6 (p = 0.04), and TNF-α (p = 0.04) levels. NCI in young men and women living with HIV was associated with higher IL-6 and TNF-α in plasma, but not in the CSF. CXCL10 was identified as a biomarker of NCI specifically in women with chronic HIV infection.

Mitochondrial biogenesis is altered in HIV+ brains exposed to ART: Implications for therapeutic targeting of astroglia

The neuropathogenesis of HIV associated neurocognitive disorders (HAND) involves disruption of mitochondrial homeostasis and increased neuroinflammation. However, it is unknown if alterations in mitochondrial biogenesis in the brain underlie the neuropathogenesis of HAND. In this study, neuropathological and molecular analyses of mitochondrial biogenesis and inflammatory pathways were performed in brain specimens from a well-characterized cohort of HIV+ cases that were on antiretroviral regimens. In vitro investigations using primary human astroglia and neurons were used to probe the underlying mechanisms of mitochondrial alterations. In frontal cortices from HAND brains compared to cognitive normal brains, total levels of transcription factors that regulate mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and transcription factor A, mitochondrial (TFAM) were decreased. Immunohistochemical analyses revealed that TFAM was decreased in neurons and increased in astroglia. These changes were accompanied by decreased total mitochondrial DNA per cell and increased levels of messenger RNA for the proinflammatory cytokine interleukin (IL)-1β. To determine how IL-1β affects astroglial bioenergetic processes and mitochondrial activity, human astroglial cultures were exposed to recombinant IL-1β. IL-1β induced mitochondrial activity within 30 min of treatment, altered mitochondrial related gene expression, altered mitochondrial morphology, enhanced adenoside triphosphate (ATP) utilization and increased the expression of inflammatory cytokines. WIN55,212-2 (WIN), an aminoalkylindole derivative and cannabinoid receptor agonist, blocked IL-1β-induced bioenergetic fluctuations and inflammatory gene expression in astroglia independent of cannabinoid receptor (CB)1 and peroxisome proliferator-activated receptor (PPAR) γ. A PPARα antagonist reversed the anti-inflammatory effects of WIN in human astroglia. These results show that mitochondrial biogenesis is differentially regulated in neurons and astroglia in HAND brains and that targeting astroglial bioenergetic processes may be a strategy to modulate neuroinflammation.

Alterations in brain TREM2 and Amyloid-β levels are associated with neurocognitive impairment in HIV-infected persons on antiretroviral therapy

Neuroinflammation is a common pathological correlate of HIV-associated neurocognitive disorders (HAND) in individuals on antiretroviral therapy (ART). Triggering receptor expressed on myeloid cells 2 (TREM2) regulates neuroinflammation, clears extracellular Amyloid (A)-β, surveys for damaged neurons, and orchestrates microglial differentiation. TREM2 has not been studied in HIV+ brain tissues. In this retrospective study, we investigated TREM2 expression levels and localization to microglia, Aβ protein levels, and tumor necrosis factor (TNF)-α transcript levels in the frontal cortices of 52 HIV+ decedents. All donors had been on ART; 14 were cognitively normal (CN), 17 had an asymptomatic neurocognitive impairment (ANI), and 21 had a minor neurocognitive disorder (MND). Total TREM2 protein levels were increased in the soluble and decreased in the membrane-enriched fractions of MND brain tissues compared to CN; however, brains from MND Hispanics showed the most robust alterations in TREM2 as well as significantly increased TNF-α mRNA and Aβ levels when compared to CN Hispanics. Significant alterations in the expression of total TREM2 protein and transcripts for TNF-α were not observed in non-Hispanics, despite higher levels of Aβ in the non-Hispanic CN group compared to the non-Hispanic MND groups. These findings show that decreased and increased TREM2 in membrane-bound fractions and in soluble-enriched fractions, respectively, is associated with increased Aβ and neuroinflammation in this cohort of HIV+ brains, particularly those identifying as Hispanics. These findings suggest a role for TREM2 in the brain of HIV+ individuals may deserve more investigation as a biomarker for HAND and as a possible therapeutic target. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.

Peripheral inflammation related to lower fMRI activation during a working memory task and resting functional connectivity among older adults: a preliminary study

OBJECTIVE

Peripheral inflammation has been associated with adverse effects on cognition and brain structure in late life, a process called 'inflammaging.' Identifying biomarkers of preclinical cognitive decline is critical in the development of preventative therapies, and peripheral inflammation may be able to serve as an indicator of cognitive decline. However, little is known regarding the relationship between peripheral inflammation and brain structure and function among older adults.

METHODS

Twenty-four older adults (mean age = 78) underwent a functional magnetic resonance imaging (fMRI) resting state functional connectivity scan, and a subset (n = 14) completed the n-Back working memory task in the scanner. All participants completed a blood draw, and inflammation was measured with interleukin 6 (IL-6) and C-Reactive Protein (CRP).

RESULTS

Surprisingly, age was unrelated to measures of inflammation (IL-6, CRP) or brain function (default mode network (DMN) connectivity; working memory performance; blood oxygenation level dependent (BOLD) activation with higher working memory load). However, lower functional connectivity between the left parietal seed and all other DMN regions was associated with higher levels of IL-6 and CRP. Additionally, greater plasma concentration of IL-6 was associated with lower BOLD activation in the left middle frontal gyrus in response to increased working memory load.

CONCLUSIONS

These preliminary findings support the importance of IL-6 and CRP in brain function among older adults. Frontal and parietal regions may be particularly sensitive to the effects of inflammation. Additionally, these findings provide preliminary evidence of inflammatory contributions to level of neural activity, even after accounting for vascular risk factors.

Abnormalities in chemokine levels in schizophrenia and their clinical correlates

Chemokines are promising biomarkers of immune activation and inflammation, but evidence for chemokine abnormalities in schizophrenia and their relationship to clinical factors remains inconclusive. We aimed to understand chemokine-related diagnostic differences and clinical correlates using a comprehensive panel and studying a large, well-characterized sample of adults with and without schizophrenia. We studied 134 outpatients with schizophrenia or schizoaffective disorder and 112 healthy comparison (HC) individuals, 26 to 65years of age. Clinical measures were obtained, and plasma levels of 11 chemokines were assessed using multiplex immunoassay. Schizophrenia vs. HC differences were tested for each chemokine, adjusting for age, gender, body mass index, and current smoking status. We also examined whether age and gender relationships differed between diagnostic groups. Using logistic regression, we created a Chemokine Index (CI) and explored its clinical correlates. Levels of monocyte chemoattractant protein-1 (MCP-1/CCL2), macrophage inflammatory protein-1β (MIP-1β/CCL4), Eotaxin-1 (CCL11), thymus and activation-regulated chemokine (TARC/CCL17), and macrophage-derived chemokine (MDC/CCL22) were significantly higher in persons with schizophrenia than HCs. Group differences in TARC were reduced after adjusting for covariates. The CI, a linear combination of Eotaxin-1 and MDC levels, was positively associated with age, duration of schizophrenia, and severity of negative symptoms. Levels of chemokines with neuroimmune regulatory effects were higher in individuals with schizophrenia, particularly in older and chronic patients. Treatments aimed at normalizing chemokine levels might improve mental and physical health among schizophrenia patients as they age.

Can research at the end of life be a useful tool to advance HIV cure?

Despite extensive investigations, we still do not fully understand the dynamics of the total body HIV reservoir and how sub-reservoirs in various compartments relate to one another. Studies using macaque models are enlightening but eradication strategies will still need to be tested in humans. To take the next steps in understanding and eradicating HIV reservoirs throughout the body, we propose to develop a “peri-mortem translational research model” of HIV-infected individuals (called ‘The Last Gift’), which is similar to existing models in cancer research. In this model, altruistic, motivated HIV-infected individuals with advanced non-AIDS related diseases and with six months or less to live will participate in HIV cure research and donate their full body after they die. Engaging this population provides a unique opportunity to compare the HIV reservoir before and after death across multiple anatomic compartments in relation to antiretroviral therapy use and other relevant clinical factors. Furthermore, people living with HIV/AIDS at the end of their lives may be willing to participate to cure interventions and accept greater risks for research participation. A broad, frank, and pragmatic discussion about performing HIV cure research near the end of life is necessary.

Immunoassay and molecular methods to investigate DNA methylation changes in peripheral blood mononuclear cells in HIV infected patients on cART

This study aimed to investigate the influence of antiretroviral therapy on methylation markers, in a group of HIV infected, heavily treated patients. Immune and molecular methods were used to investigate potential changes in methylation profile in DNA isolated from peripheral blood mononuclear cells collected from antiretroviral-experienced HIV infected patients and healthy controls. The percentage of 5-methylcytosine was inversely correlated with proviral DNA and active replication while DNMT1 (p = 0.01) and DNMT3A (p = 0.004) independently correlated with active viral replication. DNMT3A expression increased with total treatment duration (p = 0.03), number of antiretroviral drugs ever used (p = 0.003), and cumulative exposure to protease inhibitors (p = 0.02) even in currently HIV undetectable patients.

Latent toxoplasmosis is associated with neurocognitive impairment in young adults with and without chronic HIV infection

We evaluated the impact of latent toxoplasmosis (LT) on neurocognitive (NC) and neurobehavioural functioning in young adults with and without chronic HIV infection, using a standardised NC test battery, self-reported Beck Depression Inventory, Frontal System Behavior Scale, MINI-International Neuropsychiatric Interview and risk-assessment battery. 194 young adults (median age 24years, 48.2% males) with chronic HIV infection (HIV+) since childhood and 51 HIV seronegative (HIV-) participants were included. HIV+ individuals had good current immunological status (median CD4: 479 cells/μl) despite a low CD4 nadir (median: 93 cells/μl). LT (positive anti-Toxoplasma IgG antibodies) was present in one third of participants. The impairment rates in the HIV- with and without Toxo were not significantly different (p=0.17). However, we observed an increasing trend (p<0.001) in impairment rates with HIV and LT status: HIV-/LT- (6.1%); HIV-/LT+ (22%), HIV+/LT- (31%), HIV+/LT+ (49%). In a multivariable analysis using the entire study group there were main effects on cognition for HIV and also for LT. Within the HIV+ group LT was associated with worse performance globally (p=0.006), in memory (p=0.009), speed of information processing (p=0.01), verbal (p=0.02) and learning (p=0.02) domains. LT was not associated with depressive symptoms, frontal systems dysfunction or risk behaviors in any of the groups. HIV participants with lower Toxoplasma antibody concentration had worse NC performance, with higher GDS values (p=0.03) and worse learning (p=0.002), memory (p=0.006), speed of information processing (p=0.01) T scores. Latent Toxoplasmosis may contribute to NC impairment in young adults, including those with and without chronic HIV infection.

Proceedings of The 8th Romanian National HIV/AIDS Congress and The 3rd Central European HIV Forum : Sibiu, Romania. 5-7 May 2016

O1 HIV-1 diversity in Bulgaria (current molecular epidemiological picture)

Ivailo Alexiev, Reneta Dimitrova, Anna Gancheva, Asya Kostadinova, Mariyana Stoycheva, Daniela Nikolova, Ivaylo Elenkov

O2 Knowledge, attitudes and practices of the general population on HIV/AIDS, hepatitis B and C in Romania

Cătălin Tilișcan, Mioara Predescu, Bogdan Păunescu, Anca Streinu-Cercel, Oana Săndulescu, Claudiu Mihai Șchiopu, Mădălina Hristache, Lăcrămioara Aurelia Brîndușe, Adrian Streinu-Cercel

O3 The prevalence of human leukocyte antigen-B*57:01 allele carriers and CXCR4 tropism among newly diagnosed HIV infected patients in Serbia

Marija Todorovic, Marina Siljic, Dubravka Salemovic, Valentina Nikolic, Ivana Pesic-Pavlovic, Jovan Ranin, Djordje Jevtovic, Maja Stanojevic

O4 HIV transmission among stable serodiscordant couples from the former Pediatric Cohort follow up in the National Institute of Infectious Diseases

Ana Maria Tudor, Delia Vlad, Mariana Mărdărescu, Sorin Petrea, Cristina Petre, Ruxandra Neagu-Drăghicenoiu, Rodica Ungurianu, Alina Cibea, Odette Chirilă, Cristian Anghelina, Ileana Coserea

O5 Unemployment is associated with syringe sharing among people who inject drugs in Greece

Pantelia-Amalia Krikelli, Eirini Pavlitina, Mina Psichogiou, Demetris Lamnisos, Leslie Williams, Anya Korobchuk, Britt Skaathun, Pavlo Smyrnov, John Schneider, Vana Sypsa, Dimitrios Paraskevis, Angelos Hatzakis, Samuel R. Friedman, Georgios K. Nikolopoulos

O6 Correlation of adipocytokine levels in different types of lipodystrophy in HIV/AIDS patients

Gordana Dragović, Danica Srdić, Al Musalhi Khawla, Ivan Soldatović, Jelena Nikolić, Djordje Jevtović, Devaki Nair

O7 IP10 – a possible biomarker for the progression of HIV infection

Aura Temereanca, Adelina Rosca, Luminita Ene, Benchawa Soontornniyomkij, Carmen Diaconu, Claudia Dita, Cristian Achim, Simona Ruta

O8 A permanent challenge: persistent low viremia in HIV positive patients on ART

Șerban Benea, Ruxandra Moroti, Raluca Jipa, Eliza Manea, Andrada Stan, Elisabeta Benea, Dan Oțelea, Adriana Hristea

O9 Infections in IDUs according to their HIV status

Adriana Hristea, Irina Lăpădat, Raluca Jipa, Ruxandra Moroti, Șerban Benea, Doina Antonică, Irina Panait, Roxana Petre

O10 Trends in combined antiretroviral therapy used in methadone program integrated with HIV care - 20 years of experience

Justyna D. Kowalska, Ewa Pietraszkiewicz, Ewa Grycner, Ewa Firlag-Burkacka, Andrzej Horban

O11 Extracellular cyclophilin A – inflammatory mediator in HIV infected patients

Ovidiu Vlaicu, Leontina Bănică, Simona Paraschiv, Ana-Maria Tudor, Ruxandra Moroti, Dan Oțelea

O12 High cardiovascular disease risk in Serbian population, an issue of concern

Bojana Dimitrijević, Ivan Soldatović, Đorđe Jevtović, Jovana Kusić, Dubravka Salemović, Jovan Ranin, Gordana Dragović

O13 Genotypic rifampicin resistance in HIV/ tuberculosis coinfected patients from a tertiary level infectious diseases hospital

Dragoș Florea, Ioana Bădicuț, Alexandru Rafila, Cornel Camburu, Adriana Histrea, Mihaela Frățilă, Dan Oțelea

O14 Occurrence of residual HCV RNA in liver and peripheral blood mononuclear cells among patients with chronic hepatitis C infection and/or HCV/HIV coinfection after IFN-based therapy

Ivana Gmizic, Dubravka Salemovic, Ivana Pesic-Pavlovic, Marina Siljic, Valentina Nikolic, Miljana Djonin-Nenezic, Ivana Milosevic, Branko Brmbolic, Maja Stanojevic

O15 Romanian nationwide screening for infection with HIV and hepatitis B and C viruses

Anca Streinu-Cercel, Oana Săndulescu, Alina Cristina Neguț, Mioara Predescu, Alexandra Mărdărescu, Mihai Săndulescu, Adrian Streinu-Cercel

O16 Treatment emergent variants to combined direct antiviral agents therapy against hepatitis C virus

Ana Belen Pérez, Natalia Chueca, Marta Álvarez, Juan Carlos Alados, Antonio Rivero, Francisco Vera, Marcial Delgado, Javier Salmeron, Miguel Jiménez, Maria José Blanco, Moises Diago, Miguel Garcia-deltoro, Marta Alvarez, Francisco Téllez, Federico García

O17 Clinical and epidemiological aspects in tuberculosis/HIV coinfected patients

Diana Tănase, Eliza Manea, Rodica Bacruban, Dragoș Florea, Dan Oțelea, Alexandru Rafila, Mariana Mărdărescu, Adriana Hristea

O18 Resistance to NS3 protease inhibitors in persons with chronic hepatitis C infected with hepatitis C virus subtype 1a from Croatia

Ivana Grgic, Ana Planinic, Maja Santak, Lana Gorenec, Snjezana Zidovec Lepej, Adriana Vince

O19 Analysis of a simplified diagnostic score for tuberculous meningitis in HIV-infected adults with meningitis

Eliza Manea, Adriana Hristea, Șerban Benea, Ruxandra Moroti, Diana Tănase, Cristian M. Niculae, Simona Merisor, Raluca Jipa

O20 Molecular tracing of the origin of HIV-1 infection among persons who inject drugs in Athens: a phyloethnic study

Dimitrios Paraskevis, Evangelia Kostaki, Georgios K. Nikolopoulos, Vana Sypsa, Mina Psichogiou, Dimitra Paraskeva, Athanassios Skoutelis, Meni Malliori, Samuel R. Friedman, Angelos Hatzakis

O21 The dynamics of virological response to HIV-1 infection and antiretroviral therapy initiation in patients with and without HLA-B*5701 Allele

Malgorzata Hackiewicz, Piotr Zabek, Ewa Firlag-Burkacka, Andrzej Horban, Justyna Dominika Kowalska

O22 Increase in the numbers of non-B subtypes and potential recombinant forms circulating among Slovenian MSM in the recent years

Maja M. Lunar, Jana Mlakar, Mario Poljak

O23 Genotyping intrahost polymorphisms in hepatitis C virus E2 protein associated with resistance to antibody neutralization

Leontina Bănică, Eliza Martin, Valeriu Gheorghiță, Andrei Petrescu, Dan Oțelea, Costin-Ioan Popescu, Simona Paraschiv

O24 Genotyping of HCV NS3 protease inhibitors resistance and phenotyping of rare double resistance mutations in HCV cell culture system

Emil Neaga, Vlaicu Ovidiu, Andrei Juncu, Leontina Bănică, Simona Paraschiv, Dan Oțelea, Costin-Ioan Popescu

O25 Employment status controls the relationship between neurocognitive impairment and depression in a cohort of young HIV-infected adults since childhood

Adrian Luca, Florin Lazăr, Anca Elena Luca, Luminița Ene, Cristian Achim

O26 Predictors of survival in parenterally-infected HIV positive children and youth diagnosed with progressive multifocal leukoencephalopathy

Cosmina Gingăraş, Ștefan Adrian Anton, Roxana Rădoi, Simona Tetradov, Grațiela Țârdei, Maria Nica, Razvan Alexandru Capşa, Cristian L. Achim, Cristiana Oprea, Luminița Ene

O27 Neurocognitive and brain functioning in HIV-infected young MSM treated with cART

Bogna Szymańska, Natalia Gawron, Agnieszka Pluta, Emilia Łojek, Ewa Firląg – Burkacka, Andrzej Horban, Robert Bornstein, et HARMONIA3 Study Group

O28 Clinical value of RT-PCR detection of Toxoplasma gondii DNA in cerebrospinal fluid

Olivia Burcoș, Simona Manuela Erscoiu, Filofteia Bănicioiu Cojanu, Andreea Toderan, Maria Nica, Ionuț Cristian Popa, Emanoil Ceaușu, Petre Iacob Calistru

O29 Characteristics of sleep disorders in Romanian adults infected with human immunodeficiency virus

Manuela Arbune, Mirela Alexandrache, Anca-Adriana Arbune, Doina-Carina Voinescu

O30 Diagnosing neuroHIV: the rift between clinicians and pathologists

Ioan-Alexandru Diaconu, Laurențiu Stratan, Victoria Aramă, Luciana Nichita, Alexandra Diaconu, Anca Negru, Alina Orfanu, Anca Leuștean, Daniela Adriana Ion

O31 A challenging neurological complication in a HIV-infected young woman with multiple opportunistic infections

Irina Ianache, Cristiana Oprea

O32 Brain abscess with uncertain etiology in a late-presenter HIV infected patient

Anca Leuștean, Cristina Popescu, Alina Orfanu, Anca Negru, Remulus Catana, Cristina Murariu, Ioan-Alexandru Diaconu, Mihaela Rădulescu, Cătălin Tilișcan, Victoria Aramă

O33 Cerebral toxoplasmosis and left crural monoparesis with fatal evolution in a noncompliant patient with AIDS C3

Iosif Marincu, Patricia Poptelecan, Valeria Bică, Florin Lazăr, Livius Tirnea

O34 Opportunistic infections still a problem in HIV-infected patients in cART era: a Romanian single center experience

Irina Ianache, Roxana Rădoi, Manuela Nica, Grațiela Țârdei, Luminița Ene, Emanoil Ceaușu, Petre Calistru, Cristiana Oprea

P1: Epidemiological aspects of co-infection of HIV/TB in Moldova

Iurie Osoianu, Ala Halacu

P2 Perinatal exposure at HIV infection in Oltenia region

Andreea Cristina Stoian, Florentina Dumitrescu, Iulian Diaconescu, Augustin Cupșa, Lucian Giubelan, Loredana Ionescu, Irina Niculescu

P3 Women living with HIV in Mureș county

Carmen Chiriac, Nina Șincu, Iringo Zaharia Kezdi, Anca Georgescu, Brândușa Țilea, Cristina Girbovan, Andrea Incze, Andrea Fodor

P4 Late diagnosis of HIV infection in children - a challenge for Romania

Alina Cibea, Mariana Mărdărescu, Cristina Petre, Ruxandra Drăghicenoiu, Rodica Ungurianu, Ana Maria Tudor, Delia Vlad, Carina Matei

P5 Cirrhosis Assessment in Patients Co-infected HIV-Hepatitis B Virus

Elena Dumea, Lucian Cristian Petcu, Simona Claudia Cambrea

P6 HIV late presenters in Craiova Regional Center, Romania

Florentina Dumitrescu, Augustin Cupsa, Andreea Cristina Stoian, Lucian Giubelan, Irina Niculescu, Iulian Diaconescu, Dan Hurezeanu, Livia Dragonu, Mioara Cotulbea

P7 Some aspects of malignancies in patients HIV / AIDS

Simona Manuela Erscoiu, Ionuț Cristian Popa, Denisa Stroie, Petronela Ionescu, Nedeea Duță, Camelia Dobrea, Irina Voican, Emanoil Ceaușu, Petre Iacob Calistru

P8 Factors associated with resilience among people living with HIV in Romania

Florin Lazăr

P9 Fever in HIV-infected patients: a thorny problem to be solved by the clinicians

Lucian Giubelan, Augustin Cupșa, Iulian Diaconescu, Florentina Dumitrescu, Dan Hurezeanu, Livia Dragonu, Irina Niculescu, Andreea Cristina Stoian, Oana Obretin, Mariana Stănescu, Mihai Jianu

P10 Th1, Th2, Th9, Th17 and Th22 cytokines in acute and chronic HIV-1 infection

Lana Gorenec, Snjezana Zidovec Lepej, Ivana Grgic, Ana Planinic, Janja Iscic Bes, Adriana Vince, Josip Begovac

P11 Dyslipidemia in HIV-infected patients treated with protease inhibitors – case report

Luminița Elena Horga

P12 Why use less treatment for the metabolic abnormalities in HIV patients-too many drugs?

Corina Itu, Luminița Elena Horga, Laura Augusta David-Aldea, Anca Ciorogar, Cristian Jianu, Mihaela Lupșe

P13 Sacral Herpes Zoster, with hyperalgesic form, in a patient with C3 stage HIV infection

Iuliana Caramangiu, Ovidiu Roșca, Monica Cialma, Andreea Ardeleanu, Iosif Marincu

P14 Factors associated with in-hospital mortality in tuberculous and cryptococcal meningitis

Raluca Jipa, Eliza Manea, Șerban Benea, Irina Lăpădat, Nicoleta Irimescu, Irina Panait, Cristian Niculae, Adriana Hristea

P15 Lipodystrophy: still present adverse event in resource-limited settings

Jovana Kusic, Djordje Jevtovic, Dubravka Salemovic, Jovan Ranin, Bozana Dimitrijevic, Gordana Dragovic

P16 TB and HIV coinfected patient, an emergent challenge - case report

Laura-Augusta Aldea-David

P17 Efficacy of prophylactic antiretroviral treatment in new-born infants from HIV-positive mothers in 2012-2014, for the North-Eastern part of Romania

Carmen Manciuc, Cristina Nicolau, Liviu Prisăcariu, Alexandra Largu

P18 Surveillance of mother to child transmission of HIV in Romania – 31 December 2015

Mariana Mărdărescu, Adrian Streinu-Cercel, Cristina Petre, Marieta Iancu, Sanda Vintilă, Daniela Vitelaru, Iosif Ionel, Claudiu Mihai Șchiopu, Alexandra-Henriette Mărdărescu

P19 The antiretroviral therapy failure and the need to select the effective treatment in the Republic of Moldova

Pavel Micsanschi, Tiberiu Holban, Ina Bîstrițchi, Lucia Pârțână, Angela Nagîț, Svetlana Popovici, Maria Talmaci, Irina Cucerova

P20 Disseminated cryptococcosis in a patient with C3 HIV stage and multiresistant to antiretroviral therapy with lethal evolution

Sorina Georgiana Mitrescu, Dana Mihalcea, Iulia Caramangiu, Ovidiu Roșca, Iosif Maricu

P21 Aspects of tuberculosis infection in HIV-positive patients from Romania – our experience

Anca Negru, Daniela Munteanu, Victoria Aramă, Raluca Mihăilescu, Ioan Diaconu, Remulus Catana, Cristina Popescu, Alina Orfanu, Anca Leuștean, Mihaela Rădulescu, Cătălin Tilișcan, Raluca Năstase, Violeta Molagic, Irina Duport, Cristina Dragomirescu, Ștefan Sorin Aramă

P22 Dyslipidemia in HIV-infected patients

Nicoleta M Negruț

P23 Challenges in the management of an HIV seropositive patient with psoriasis undergoing immunomodulator therapy

Violeta Elena Niță, Daniela Ioana Munteanu, Raluca Mihăilescu, Ioan Diaconu, Anca Negru, Cristina Popescu, Victoria Aramă

P24 Acute peritonitis as a sign of IRIS in an HIV-infected patient with MAC latent infection

Alina Orfanu, Cristina Popescu, Anca Leuștean, Anca Negru, Remulus Catana, Ioan Diaconu, Cătălin Tilișcan, Victoria Aramă, Sorin Ștefan Aramă

P25 The virologic outcome of the treatment of chronic hepatitis B among HIV co-infected patients on HAART

Ivana Pesic Pavlovia, Dubravka Salemovic, Jovan Ranin, Djordje Jevtovic

P26 A case of HIV encephalopathy with aphasia, agnosia, apraxia and right homonymous hemianopsia

Ovidiu Roșca, Andreea Ardeleanu, Iulia Caramangiu, Daniela Desaga, Valerica Bică, Sorina Mitrescu, Iosif Marincu

P27 Molecular footprints on human immunodeficiency virus -1 genome and association with phylogenetic clustering among subtype B infected patients in Serbia

Marina Siljic, Dubravka Salemovic, Valentina Nikolic, Djordje Jevtovic, Ivana Pesic-Pavlovic, Jovan Ranin, Marija Todorovic , Maja Stanojevic

P28 Neurosyphilis and human immunodeficiency virus infection: double challenge

Nina-Ioana Șincu, Anca Georgescu, Brândușa Țilea, Iringo Zaharia Kezdi, Andrea Incze, Cristina Gârbovan, Carmen Lucia Chiriac

P29 Differences between HIV-infected adults since childhood and non HIV-infected persons on managing everyday life

Anca Elena Luca, Florin Lazăr, Adrian Luca, Luminița Ene, Roxana Rădoi, Adina Talnariu, Silvia Suciu, Cristian Achim

P30 Molecular detection of Bartonella quintana in a HIV immunodepressed patient with fever and isolated lymphadenopathy - Case report

Diana Gabriela Iacob, Dragoș Florea, Simona Iacob

P31 Present epidemiological characteristics of HIV/AIDS newly diagnosed cases in South-Eastern Romania

Manuela Arbune, Miruna Drăgănescu, Alina Iancu

P32 The gender’s preferences among opportunists?

Ruxandra Moroti, Cristian M Niculae, Simona Merisor, Eliza Manea, Serban Benea, Andrada Stan, Raluca Hrisca, Raluca Jipa, Diana Tanase, Adriana Hristea

P33 Polymorphism of interleukin-28B gene in persons with chronic hepatitis C from Croatia

Ivana Grgic, Ana Planinic, Lana Gorenec, Snjezana Zidovec Lepej, Adriana Vince

Lifetime methamphetamine dependence is associated with cerebral microgliosis in HIV-1-infected adults

Methamphetamine (Meth) use is common among HIV-infected persons. It remains unclear whether Meth dependence is associated with long-lasting degenerative changes in the brain parenchyma and microvasculature of HIV-infected individuals. We examined the postmortem brains of 78 HIV-infected adults, twenty of whom were diagnosed with lifetime Meth dependence (18 past and two current at the final follow-up visit). Using logistic regression models, we analyzed associations of Meth with cerebral gliosis (immunohistochemistry for ionized calcium-binding adapter molecule-1 (Iba1) and glial fibrillary acidic protein (GFAP) in frontal, temporo-parietal, and putamen-internal capsule regions), synaptodendritic loss (confocal microscopy for synaptophysin (SYP) and microtubule-associated protein-2 (MAP2) in frontal cortex), β-amyloid plaque deposition (immunohistochemistry in frontal and temporo-parietal cortex and putamen), and arteriolosclerosis (histopathology in forebrain white matter). We found that Meth was associated with marked Iba1 gliosis in the temporo-parietal region (odds ratio, 4.42 (95 % confidence interval, 1.36, 14.39), p = 0.014, n = 62), which remained statistically significant after adjusting for HIV encephalitis, white matter lesions, and opportunistic diseases (n = 61); hepatitis C virus seropositivity (n = 54); and lifetime dependence on alcohol, opiates, and cannabis (n = 62). There was no significant association of Meth with GFAP gliosis, SYP or MAP2 loss, β-amyloid plaque deposition, or arteriolosclerosis. In conclusion, we found lifetime Meth dependence to be associated with focal cerebral microgliosis among HIV-infected adults, but not with other brain degenerative changes examined. Some of the changes in select brain regions might be reversible following extended Meth abstinence or, alternatively, might have not been induced by Meth initially.

Age and High-Fat Diet Effects on Glutamine Synthetase Immunoreactivity in Liver and Hippocampus and Recognition Memory in Mice

BACKGROUND

High-Fat Diet (HFD)-induced obesity may promote agerelated memory impairment via disturbances of ammonia-glutamine metabolism.

OBJECTIVE

We studied the effects of age and long-term HFD exposure on Glutamine Synthetase (GS) expression in the liver and hippocampus and recognition memory in mice.

METHODS

Adult (5-month-old) and aged (15-month-old) male C57BL/6 mice were exposed to control diet (CD, 14% calories from fat) or HFD (60% fat). Novel place recognition testing was conducted and tissue was collected after 4 and 5 months on HFD, respectively. Tissue GS expression levels were assessed using immunohistochemistry and image analysis.

RESULTS

The obese mice developed moderate/severe hepatic steatosis. GS immunoreactivity was observed in perivenous hepatocytes and in hippocampal astrocytes and neuropil. Hepatic GS immunoreactivity density was higher in aged mice on HFD (n = 8) than CD (n = 13, P = 0.004). In aged mice, hippocampal GS immunoreactivity density was higher with HFD than CD (P = 0.037). In the novel place recognition test, aged mice were classified into impaired (n = 7) and unimpaired (n = 12), relative to adult mice (n = 22). Hippocampal GS immunoreactivity density was higher in impaired than unimpaired aged mice (P < 0.05).

CONCLUSION

Long-term exposure of aged mice to HFD was associated with increased GS expression in the liver and hippocampus. Novel place recognition impairment in aged mice was associated with increased hippocampal GS expression. These findings suggest that excess ammonia is involved in the age-related effects of HFD exposure and in neurotoxicity.

Multilevel analysis of neuropathogenesis of neurocognitive impairment in HIV

The neuropathogenesis of HIV-associated neurocognitive disorders (HAND) remains puzzling. We interrogated several levels of data (host genetic, histopathology, brain viral load, and neurocognitive) to identify histopathological changes most relevant to HAND. The design of the study is a clinicopathological study employing genetic association analyses. Data and brain tissue from 80 HIV-infected adults were used. Markers in monocyte chemoattractant protein-1 (MCP-1), interleukin 1-alpha (IL1-α), macrophage inflammatory protein 1-alpha (MIP1-α), DRD3, DRD2, and apolipoprotein E (ApoE) were genotyped. Microtubule associated protein 2 (MAP2), synaptophysin (SYP), human leukocyte antigen-DR (HLA-DR), glial fibrillary acidic protein (GFAP), amyloid beta (A-Beta), and ionized calcium-binding adaptor molecule-1 (Iba-1) immunoreactivity were quantified in the frontal cortex, putamen, and hippocampus. A composite score for each marker (mean of the three brain regions) was used. Neurocognitive functioning and other clinical variables were determined within 1 year of death. Brain HIV RNA viral load was available for a subset of cases. MAP2 and SYP proved most relevant to neurocognitive functioning. Immunoreactivity of these markers, as well as A-Beta and Iba-1, was correlated with brain HIV RNA viral load. Several genetic markers in combination with other factors predicted histopathology: HIV blood viral load, MIP1-α genotype, and DRD3 genotype predicted Iba-1 immunoreactivity; the duration of infection and IL1-α genotype predicted GFAP immunoreactivity; ApoE genotype and age at death predicted A-Beta immunoreactivity. These data indicate that HIV replication in the brain is the primary driving force leading to neuroinflammation and dysfunctional protein clearance, as reflected by A-Beta and Iba-1. Downstream to these changes are synaptodendritic degeneration, which is the immediate histopathological substrate of the neurocognitive impairment characteristic of HAND. These intermediate histopathological phenotypes are influenced by host genetic polymorphisms in genes encoding cytokines/chemokines, neuronal protein clearance pathways, and dopaminergic factors.

Spatial Cognition in Adult and Aged Mice Exposed to High-Fat Diet

Aging is associated with a decline in multiple aspects of cognitive function, with spatial cognition being particularly sensitive to age-related decline. Environmental stressors, such as high-fat diet (HFD) exposure, that produce a diabetic phenotype and metabolic dysfunction may indirectly lead to exacerbated brain aging and promote the development of cognitive deficits. The present work investigated whether exposure to HFD exacerbates age-related cognitive deficits in adult versus aged mice. Adult (5 months old) and aged (15 months old) mice were exposed to control diet or HFD for three months prior to, and throughout, behavioral testing. Anxiety-like behavior in the light-dark box test, discrimination learning and memory in the novel object/place recognition tests, and spatial learning and memory in the Barnes maze test were assessed. HFD resulted in significant gains in body weight and fat mass content with adult mice gaining significantly more weight and adipose tissue due to HFD than aged mice. Weight gain was attributed to food calories sourced from fat, but not total calorie intake. HFD increased fasting insulin levels in all mice, but adult mice showed a greater increase relative to aged mice. Behaviorally, HFD increased anxiety-like behavior in adult but not aged mice without significantly affecting spatial cognition. In contrast, aged mice fed either control or HFD diet displayed deficits in novel place discrimination and spatial learning. Our results suggest that adult mice are more susceptible to the physiological and anxiety-like effects of HFD consumption than aged mice, while aged mice displayed deficits in spatial cognition regardless of dietary influence. We conclude that although HFD induces systemic metabolic dysfunction in both adult and aged mice, overall cognitive function was not adversely affected under the current experimental conditions.

Hepatitis B virus compartmentalization in the cerebrospinal fluid of HIV-infected patients

We detected hepatitis B virus (HBV) DNA in the cerebrospinal fluid (CSF) of 26 adolescents co-infected with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) with neurological disease and studied compartmentalization of HBV in the CSF. More than half of the subjects with positive HBV DNA plasma also had CSF positive for HBV. CSF HBV DNA was found in subjects with preserved blood-brain barrier integrity. In a subgroup of these subjects, compartmentalized evolution of HBV was demonstrated by distinct profiles of resistance mutations. Future studies are warranted to determine the clinical significance of HBV presence in the CSF and its contribution to HIV-associated neurological disease.

Neurocognitive functioning in a Romanian cohort of young adults with parenterally-acquired HIV-infection during childhood

The Romanian cohort can provide valuable information about the effect of chronic HIV-infection and exposure to combined antiretroviral therapy (cART) on the developing brain, based on its unique characteristics: young adults infected parenterally with HIV clade F in the late 1980s and exposed to cART for a decade. We conducted a prospective study using a neuropsychological test battery validated in other international HIV cohorts, in order to evaluate the rate and severity of neurocognitive impairment in a group of young Romanian adults. The 49 HIV-infected (HIV+) participants and the 20 HIV negative (HIV-) controls were similar for age and gender, although the HIV- group tended to be more educated. We found higher cognitive impairment prevalence in the HIV+ group (59.1 %) versus the HIV- group (10 %), and the impairment rate remained significantly higher even when the groups were matched based on the educational level (38.7 % for the HIV+ group vs. 10.0 % for the HIV- controls; p = 0.025). The nadir CD4 count was <200 in 71.4 % of patients, but at the time of neurocognitive assessment, 89.5 % of patients had normal immunological status and 81.8 % undetectable HIV load. Among the HIV-impaired group, 26 % of the participants had syndromic impairment while the other 74 % had asymptomatic neurocognitive impairment. We found a high prevalence of neurocognitive dysfunction in the Romanian young adults growing-up with HIV. The greatest HIV-related cognitive deficits were in the domains of executive and motor functioning, consistent with a frontosubcortical pattern.

Cytokine secretion from brain macrophages infected with human immunodeficiency virus in vitro and treated with raltegravir

Background

Integrase inhibitors are a promising class of antiretroviral drugs to treat chronic human immunodeficiency virus (HIV) infection. During HIV infection, macrophages can extravasate from the blood to the brain, while producing chemotaxic proteins and cytokines, which have detrimental effects on central nervous system cells. The main goal of this study was to understand the effects of raltegravir (RAL) on human brain macrophage production of immune-mediators when infected with HIV, but did not compare with other antiretroviral agents.

Methods

Pro-inflammatory cytokines, IFN-γ, IL-10, IL-12-p70, IL-1, IL-8, TNF-α, and IL-6 were measured simultaneously in tissue culture supernatants from primary brain derived macrophages, microglia. We tested the effects of RAL on markers of astrocytosis and neurite integrity in primary human neuroglial cultures.

Results

RAL administered at 20 nM effectively suppressed HIV infection in microglia over 9 days. Only IL-8, IL-10, and TNF-α were above the detection limit in the majority of samples and RAL significantly suppressed the rate of cytokine production in HIV-infected microglia. During RAL-alone, the rate of IL-8 secretion was higher.

Conclusions

RAL did not affect neurite area but inhibited astrocyte growth in the neuroglial cultures. Exploring the effects of RAL on pro-inflammatory molecule production in brain macrophages may contribute to designing ARV neuroprotective strategies in chronic HIV infection.

Intracellular mannose binding lectin mediates subcellular trafficking of HIV-1 gp120 in neurons

Human immunodeficiency virus-1 (HIV-1) enters the brain early during infection and leads to severe neuronal damage and central nervous system impairment. HIV-1 envelope glycoprotein 120 (gp120), a neurotoxin, undergoes intracellular trafficking and transport across neurons; however mechanisms of gp120 trafficking in neurons are unclear. Our results show that mannose binding lectin (MBL) that binds to the N-linked mannose residues on gp120, participates in intravesicular packaging of gp120 in neuronal subcellular organelles and also in subcellular trafficking of these vesicles in neuronal cells. Perinuclear MBL:gp120 vesicular complexes were observed and MBL facilitated the subcellular trafficking of gp120 via the endoplasmic reticulum (ER) and Golgi vesicles. The functional carbohydrate recognition domain of MBL was required for perinuclear organization, distribution and subcellular trafficking of MBL:gp120 vesicular complexes. Nocodazole, an agent that depolymerizes the microtubule network, abolished the trafficking of MBL:gp120 vesicles, suggesting that these vesicular complexes were transported along the microtubule network. Live cell imaging confirmed the association of the MBL:gp120 complexes with dynamic subcellular vesicles that underwent trafficking in neuronal soma and along the neurites. Thus, our findings suggest that intracellular MBL mediates subcellular trafficking and transport of viral glycoproteins in a microtubule-dependent mechanism in the neurons.

Short-term recognition memory correlates with regional CNS expression of microRNA-138 in mice

OBJECTIVES

We hypothesized that microRNA (miR) expression may be involved in memory function because it controls local protein translation at synapses and dendritic spines.

DESIGN

Case-control animal study.

METHODS

We assessed the miR repertoire in the hippocampus of young, 6-month-old (N = 18) mice compared with aged, 26-month-old (N = 23) mice and compared miR quantity to memory scores as determined by the novel object recognition task. We performed a histological brain regional analysis of miR-138, acyl protein thioesterase 1 (APT1) mRNA, and APT1 protein.

RESULTS

We found that higher miR-138 expression in the mouse hippocampus is correlated with better memory performance. We also found that APT1 (a depalmytoylation enzyme expressed at dendritic spines whose translation is controlled by miR-138) mRNA is increased in the mouse hippocampal CA1 and dentate gyrus in aged mice compared with young mice, but not in mice with memory impairment. We found APT1 protein distribution to be lower in cells with high miR-138 expression.

CONCLUSIONS

These results suggest that increased miR-138 is associated with better memory and increased APT1 gene transcription occurs with aging. The role of miR-138 and APT1 protein function in memory and aging warrants further investigation.

Global NeuroAIDS roundtable

In May 2012, the Division of AIDS Research at the National Institute of Mental Health (NIMH) organized the "Global NeuroAIDS Roundtable" in conjunction with the 11th International Symposium on Neurovirology and the 2012 Conference on HIV in the Nervous System. The meeting was held in New York, NY, USA and brought together NIMH-funded investigators who are currently working on projects related to the neurological complications of AIDS (NeuroAIDS) in Africa, Asia, Eastern Europe, and Latin America in order to provide an opportunity to share their recent findings and discuss the challenges encountered within each country. The major goals of the roundtable were to evaluate HIV-associated neurocognitive impairment and determine if it may be directly attributable to distinct HIV subtypes or clades and to discuss the future priorities for global NeuroAIDS research. At the "Global NeuroAIDS Roundtable", presentations of preliminary research indicated that HIV-associated neurocognitive impairment is prevalent in all countries examined regardless of which HIV clade is present in the region. The only clear-cut difference between HIV-1 clades was in relation to subtypes A and D in Uganda. However, a key point that emerged from the discussions was that there is an urgent need to standardize neurocognitive assessment methodologies across the globe before definitive conclusions can be drawn regarding the relationship between HIV clade diversity and neuropathogenesis. Future research directions were also discussed at the roundtable with particular emphasis on the potential of viral and host factor molecular interactions to impact the pathophysiology of HIV-associated neurocognitive disorders (HAND) from a global perspective.

Hippocampal calbindin-1 immunoreactivity correlate of recognition memory performance in aged mice

Aging-related dysregulation of neuronal calcium metabolism, which not only involves the control of calcium fluxes but also the cytosolic calcium buffering system such as calbindin-1 (Calb1), may disturb synaptic plasticity and thereby memory functioning. Calb1 expression has been shown to affect hippocampal long-term potentiation and learning and to play a neuroprotective role in animal models of ischemic brain injury and neurodegenerative disorders. We hypothesize that memory performance in aged mice correlates with neuronal Calb1 protein expression in the hippocampal formation. We studied a set of 18 aged and 22 young male C57BL/6N mice, in which the aged group performed poorer than the young in single-trial novel object recognition testing (two-tailed p=0.005, U test). Apparent decreases in the Calb1 immunoreactivity (measured by quantitative immunohistochemistry) in aged mice compared to that in young mice were not statistically significant either in the hippocampal CA1 subfield or dentate gyrus. In the aged mouse group, levels of Calb1 immunoreactivity both in the CA1 subfield and dentate gyrus correlated directly with the measure of recognition memory performance (Spearman rank correlation r(s)=0.47 and 0.48, two-tailed p=0.047 and 0.044, respectively). Our results suggest that hippocampal Calb1 expression affects memory performance in aged mice probably via its role in maintaining neuronal calcium homeostasis. Alternatively, our finding of lower Calb1 immunoreactivity with poorer memory performance in aged mice might be attributed to saturation of Calb1 protein by higher levels of intracellular calcium, due to aging-related dysregulation of neuronal calcium fluxes.

Increased hippocampal accumulation of autophagosomes predicts short-term recognition memory impairment in aged mice

Constitutive macroautophagy involved in the turnover of defective long-lived proteins and organelles is crucial for neuronal homeostasis. We hypothesized that macroautophagic dysregulation in selective brain regions was associated with memory impairment in aged mice. We used the single-trial object recognition test to measure short-term memory in 18 aged mice compared to 22 young mice and employed immunohistochemistry to assess cellular distribution of proteins involved in the selective degradation of ubiquitinated proteins via macroautophagy. Values of the discrimination ratio (DR, a measure of short-term recognition memory performance) in aged mice were significantly lower than those in young mice (median, 0.54 vs. 0.67; p = 0.005, U test). Almost exclusively in aged mice, there were clusters of puncta immunoreactive for microtubule-associated protein 1 light chain 3 (LC3), ubiquitin- and LC3-binding protein p62, and ubiquitin in neuronal processes predominantly in the hippocampal formation, olfactory bulb/tubercle, and cerebellar cortex. The hippocampal burden of clustered puncta immunoreactive for LC3 and p62 exhibited inverse linear correlations with DR in aged mice (ρ = -0.48 and -0.55, p = 0.044 and 0.018, respectively, Spearman's rank correlation). These findings suggest that increased accumulation of autophagosomes within neuronal processes in selective brain regions is characteristic of aging. The dysregulation of macroautophagy can adversely affect the turnover of aggregate-prone proteins and defective organelles, which may contribute to memory impairment in aged mice.

Tyrosine kinase B protein expression is reduced in the cerebellum of patients with bipolar disorder

BACKGROUND

The role of the cerebellum in coordinating mental activity is supported by its connections with cerebral regions involved in cognitive/affective functioning, with decreased activities on functional neuroimaging observed in the cerebellum of schizophrenia patients performing mental tasks. Brain-derived neurotrophic factor (BDNF)-induced activation of tyrosine kinase B (TrkB) is essential to synaptic plasticity. We hypothesized that alterations in BDNF and TrkB expression in the cerebellum were associated with schizophrenia and affective disorders.

METHODS

We employed immunohistochemistry and immunoblotting to quantify protein expression of BDNF and TrkB in the cerebellum of patients with schizophrenia, bipolar disorder, and major depression compared to controls (n=15 each).

RESULTS

While TrkB immunoreactivity in each of the molecular and granule-cell layers was reduced in all 3 disease groups (12-34%) compared to the control (P=0.018 and 0.038, respectively, ANOVA), only the reduction in bipolar disorder remained statistically significant upon Tukey-Kramer post hoc analyses (P=0.019 and 0.021, respectively). Apparent decreases in BDNF immunoreactivity in all 3 disease groups (12-30%) compared to the control were not statistically significant. TrkB immunoreactivity was not significantly associated with any of the demographic, clinical, and postmortem variables. Immunoblotting displayed an 85-kDa TrkB-immunoreactive band, consistent with a truncated isoform, in all 60 cases.

LIMITATIONS

On immunoblotting, apparent decreases in 85-kDa-TrkB levels in all 3 disease groups compared to the control were not statistically significant.

CONCLUSIONS

Our finding of reduced TrkB expression in bipolar disorder suggests that dysregulation of TrkB-mediated neurotrophin signaling in the cerebellum may play a role in the pathophysiology of this disease.

Phosphorylation of collapsin response mediator protein-2 disrupts neuronal maturation in a model of adult neurogenesis: Implications for neurodegenerative disorders

BACKGROUND

Recent studies suggest that the pathogenic process in neurodegenerative disorders may disrupt mature neuronal circuitries and neurogenesis in the adult brain. Abnormal activation of CDK5 is associated with neurodegenerative disorders, and recently a critical role for CDK5 in adult neurogenesis has been identified. We have developed an in vitro model of abnormal CDK5 activation during adult hippocampal neurogenesis, and here we used this model to investigate aberrantly phosphorylated downstream targets of CDK5.

RESULTS

Abnormal CDK5 activation in an in vitro model of adult neurogenesis results in hyperphosphorylation of collapsin-response mediator protein-2 (CRMP2) and impaired neurite outgrowth. Inhibition of CDK5, or expression of a non-phosphorylatable (S522A) CRMP2 construct reduced CRMP2 hyperphosphorylation, and reversed neurite outgrowth deficits. CRMP2 plays a role in microtubule dynamics; therefore we examined the integrity of microtubules in this model using biochemical and electron microscopy techniques. We found that microtubule organization was disrupted under conditions of CDK5 activation. Finally, to study the relevance of these findings to neurogenesis in neurodegenerative conditions associated with HIV infection, we performed immunochemical analyses of the brains of patients with HIV and transgenic mice expressing HIV-gp120 protein. CDK5-mediated CRMP2 phosphorylation was significantly increased in the hippocampus of patients with HIV encephalitis and in gp120 transgenic mice, and this effect was rescued by genetic down-modulation of CDK5 in the mouse model.

CONCLUSIONS

These results reveal a functional mechanism involving microtubule destabilization through which abnormal CDK5 activation and CRMP2 hyperphosphorylation might contribute to defective neurogenesis in neurodegenerative disorders such as HIV encephalitis.

Increased CDK5 expression in HIV encephalitis contributes to neurodegeneration via tau phosphorylation and is reversed with Roscovitine

Recent treatments with highly active antiretroviral therapy (HAART) regimens have been shown to improve general clinical status in patients with human immunodeficiency virus (HIV) infection; however, the prevalence of cognitive alterations and neurodegeneration has remained the same or has increased. These deficits are more pronounced in the subset of HIV patients with the inflammatory condition known as HIV encephalitis (HIVE). Activation of signaling pathways such as GSK3β and CDK5 has been implicated in the mechanisms of HIV neurotoxicity; however, the downstream mediators of these effects are unclear. The present study investigated the involvement of CDK5 and tau phosphorylation in the mechanisms of neurodegeneration in HIVE. In the frontal cortex of patients with HIVE, increased levels of CDK5 and p35 expression were associated with abnormal tau phosphorylation. Similarly, transgenic mice engineered to express the HIV protein gp120 exhibited increased brain levels of CDK5 and p35, alterations in tau phosphorylation, and dendritic degeneration. In contrast, genetic knockdown of CDK5 or treatment with the CDK5 inhibitor roscovitine improved behavioral performance in the water maze test and reduced neurodegeneration, abnormal tau phosphorylation, and astrogliosis in gp120 transgenic mice. These findings indicate that abnormal CDK5 activation contributes to the neurodegenerative process in HIVE via abnormal tau phosphorylation; thus, reducing CDK5 might ameliorate the cognitive impairments associated with HIVE.

Family history of dementia predicts worse neuropsychological functioning among HIV-infected persons

HIV-negative individuals with a family history of dementia (FHD) are more likely to develop dementia than those without FHD. Whether FHD increases risk for neuropsychological (NP) impairment in HIV+ persons is unknown. As part of a multisite study into HIV-associated neurocognitive disorders (HAND), the authors captured FHD with a free-response, self-report question, and assessed NP performance with a comprehensive battery of tests. The authors examined HIV+ persons with (N=190) and without (N=916) self-reported FHD. Despite the fact that the FHD group had factors typically associated with better NP performance (e.g., higher CD4 counts and estimated verbal IQ), persons with FHD had significantly worse NP ability than those without FHD as measured by a Global Deficit Score. Thus, FHD appears to be a risk factor for HAND; the mechanism(s) underlying how FHD contributes to NP impairment among HIV+ persons warrants study.

Erythropoietin plus insulin-like growth factor-I protects against neuronal damage in a murine model of human immunodeficiency virus-associated neurocognitive disorders

OBJECTIVE

Prolonged human immunodeficiency virus-1 (HIV-1) infection leads to neurological debilitation, including motor dysfunction and frank dementia. Although pharmacological control of HIV infection is now possible, HIV-associated neurocognitive disorders (HAND) remain intractable. Here, we report that chronic treatment with erythropoietin (EPO) and insulin-like growth factor-I (IGF-I) protects against HIV/gp120-mediated neuronal damage in culture and in vivo.

METHODS

Initially, we tested the neuroprotective effects of various concentrations of EPO, IGF-I, or EPO+IGF-I from gp120-induced damage in vitro. To assess the chronic effects of EPO+IGF-I administration in vivo, we treated HIV/gp120-transgenic or wild-type mice transnasally once a week for 4 months and subsequently conducted immunohistochemical analyses.

RESULTS

Low concentrations of EPO+IGF-I provided neuroprotection from gp120 in vitro in a synergistic fashion. In vivo, EPO+IGF-I treatment prevented gp120-mediated neuronal loss, but did not alter microgliosis or astrocytosis. Strikingly, in the brains of both humans with HAND and gp120-transgenic mice, we found evidence for hyperphosphorylated tau protein (paired helical filament-I tau), which has been associated with neuronal damage and loss. In the mouse brain following transnasal treatment with EPO+IGF-I, in addition to neuroprotection we observed increased phosphorylation/activation of Akt (protein kinase B) and increased phosphorylation/inhibition of glycogen synthase kinase (GSK)-3beta, dramatically decreasing downstream hyperphosphorylation of tau. These results indicate that the peptides affected their cognate signaling pathways within the brain parenchyma.

INTERPRETATION

Our findings suggest that chronic combination therapy with EPO+IGF-I provides neuroprotection in a mouse model of HAND, in part, through cooperative activation of phosphatidylinositol 3-kinase/Akt/GSK-3beta signaling. This combination peptide therapy should therefore be tested in humans with HAND.

Short-term recognition memory impairment is associated with decreased expression of FK506 binding protein 51 in the aged mouse brain

Evidence suggests that increased glucocorticoid receptor (GR) signaling may contribute to cognitive decline with age. We hypothesized that alterations in GR signaling pathway molecules, FK506 binding protein (FKBP) 51 and FKBP52, were associated with memory impairment in aged mice. We used the single-trial object recognition test to measure short-term memory in 18 aged mice compared to 22 young mice, and employed quantitative immunohistochemistry to assess cellular expression of those three proteins in the frontal cortex, hippocampal CA1, and dentate gyrus. Values of the discrimination ratio (DR, a measure of novelty preference) in aged mice were significantly lower than those in young mice (mean 0.54 vs. 0.67, p = 0.003, t test). Aged mice with DR below 0.54 were considered impaired (n = 9). In the three neuroanatomic regions studied, the immunoreactivity normalized to the area measured (IRn) for GR was significantly increased in aged mice regardless of their task performance compared to young mice (p < 0.005), as was the FKBP52 IRn (p < 0.007, U test). In the frontal cortex and CA1, the FKBP51 IRn was significantly lower in impaired aged mice than in unimpaired aged mice (p < 0.01 and <0.05, respectively) and in young mice (p < 0.05 and <0.01, respectively, Dunn's post hoc test). In aged mice, the frontal cortex FKBP51 IRn correlated directly with DR (r (s) = 0.68, p = 0.002, Spearman rank correlation). These observations suggest that recognition memory impairment in aged mice is associated with decreased FKBP51 expression that may promote GR-mediated glucocorticoid signaling to a greater extent than in unimpaired aged mice.

Glycogen synthase kinase-3beta (GSK-3beta) inhibitors AR-A014418 and B6B3O prevent human immunodeficiency virus-mediated neurotoxicity in primary human neurons

Glycogen synthase kinase-3beta (GSK3beta) role in human immunodeficiency virus(HIV)-associated neurodegeneration has been evidenced by previous investigations. In this study, we investigated the specificity of two GSK3beta-specific inhibitors, AR-A014418 (A) and B6B30 (B) to prevent direct neurotoxicity in primary human neurons exposed to HIV (BaL). Neurons were exposed to HIV (500 pg/ml) for 12-h and 6-day periods in the presence and absence of A (1 microM, 100 nM, 10 nM) and B (50 nM, 5 nM, 500 pM) to investigate acute and ongoing mechanisms of HIV neurotoxicity. Using an lactate dehydrogenase (LDH) assay to assess cytotoxicity, we observed a significant neurotoxic effect of HIV from control values (P < .01) that was not restored via coexposures of all concentrations of A and B. Additionally, no change in LDH levels were observed after 6 days. However, activity of the acute proapoptotic markers caspases 3 and 7 using a luminescence assay were measured and found to be increased by exposure to HIV (BaL) compared to controls (P = .022). This effect was ameliorated via coexposure to all concentrations of A and 50 nM B after 12 h (P < .01) and to all concentrations of A and B after 6 days (P < .01). Overall, the results from this study provide further evidence for the ability of GSK3beta inhibition to be neuroprotective against HIV-associated neurotoxicity by reducing HIV associated procaspase induction. These data support a role for GSK3beta as a potential therapeutic target and may have important clinical implications for treatment of HIV-associated neurocognitive disorder.

Evidence for Alteration of Gene Regulatory Networks through MicroRNAs of the HIV-infected brain: novel analysis of retrospective cases

HIV infection disturbs the central nervous system (CNS) through inflammation and glial activation. Evidence suggests roles for microRNA (miRNA) in host defense and neuronal homeostasis, though little is known about miRNAs' role in HIV CNS infection. MiRNAs are non-coding RNAs that regulate gene translation through post-transcriptional mechanisms. Messenger-RNA profiling alone is insufficient to elucidate the dynamic dance of molecular expression of the genome. We sought to clarify RNA alterations in the frontal cortex (FC) of HIV-infected individuals and those concurrently infected and diagnosed with major depressive disorder (MDD). This report is the first published study of large-scale miRNA profiling from human HIV-infected FC. The goals of this study were to: 1. Identify changes in miRNA expression that occurred in the frontal cortex (FC) of HIV individuals, 2. Determine whether miRNA expression profiles of the FC could differentiate HIV from HIV/MDD, and 3. Adapt a method to meaningfully integrate gene expression data and miRNA expression data in clinical samples. We isolated RNA from the FC (n = 3) of three separate groups (uninfected controls, HIV, and HIV/MDD) and then pooled the RNA within each group for use in large-scale miRNA profiling. RNA from HIV and HIV/MDD patients (n = 4 per group) were also used for non-pooled mRNA analysis on Affymetrix U133 Plus 2.0 arrays. We then utilized a method for integrating the two datasets in a Target Bias Analysis. We found miRNAs of three types: A) Those with many dysregulated mRNA targets of less stringent statistical significance, B) Fewer dysregulated target-genes of highly stringent statistical significance, and C) unclear bias. In HIV/MDD, more miRNAs were downregulated than in HIV alone. Specific miRNA families at targeted chromosomal loci were dysregulated. The dysregulated miRNAs clustered on Chromosomes 14, 17, 19, and X. A small subset of dysregulated genes had many 3′ untranslated region (3′UTR) target-sites for dysregulated miRNAs. We provide evidence that certain miRNAs serve as key elements in gene regulatory networks in HIV-infected FC and may be implicated in neurobehavioral disorder. Finally, our data indicates that some genes may serve as hubs of miRNA activity.

Hepatocyte growth factor (HGF) modulates GABAergic inhibition and seizure susceptibility

Disrupted ontogeny of forebrain inhibitory interneurons leads to neurological disorders, including epilepsy. Adult mice lacking the urokinase plasminogen activator receptor (Plaur) have decreased numbers of neocortical GABAergic interneurons and spontaneous seizures, attributed to a reduction of hepatocyte growth factor/scatter factor (HGF/SF). We report that by increasing endogenous HGF/SF concentration in the postnatal Plaur null mouse brain maintains the interneuron populations in the adult, reverses the seizure behavior and stabilizes the spontaneous electroencephalogram activity. The perinatal intervention provides a pathway to reverse potential birth defects and ameliorate seizures in the adult.

Modulation of glucocorticoid receptor nuclear translocation in neurons by immunophilins FKBP51 and FKBP52: implications for major depressive disorder

Mood disorders associated with dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis are common psychiatric conditions. The glucocorticoid receptor (GR) is a steroid-activated nuclear receptor that, upon binding to cortisol, translocates to the nucleus where it targets genes related to neuronal metabolism and plasticity. In patients suffering from major depressive disorder (MDD), hypercortisolemia is a common finding. In the current study we investigated the molecular events associated with the FK506 binding proteins (FKBP) -52 and -51 response to cortisol exposure in neuronal cell cultures and their effect on GR translocation. We noted that FK506 altered nuclear localization of the GR and inhibited expression of GR-responsive genes. Furthermore, siRNA knockdown of FKBP4 gene, coding for the immunophilin FKBP52, inhibited cortisol-activated GR nuclear translocation, while knockdown of FKBP5, coding for immunophilin FKBP51, was associated with increased baseline GR nuclear localization. We propose that immunophilins are modulators of the cortisol-HPA axis response to stress and related chronic brain disorders.

Increased accumulation of intraneuronal amyloid beta in HIV-infected patients

In recent years, human immunodeficiency virus (HIV)-infected patients under highly active anti-retroviral therapy (HAART) regimens have shown a markedly improved general clinical status; however, the prevalence of mild cognitive disorders has increased. We propose that increased longevity with HIV-mediated chronic inflammation combined with the secondary effects of HAART may increase the risk of early brain aging as shown by intraneuronal accumulation of abnormal protein aggregates like amyloid beta (Abeta), which might participate in worsening the neurodegenerative process and cognitive impairment in older patients with HIV. For this purpose, levels and distribution of Abeta immunoreactivity were analyzed in the frontal cortex of 43 patients with HIV (ages 38-60) and HIV- age-matched controls. Subcellular localization of the Abeta-immunoreactive material was analyzed by double labeling and confocal microscopy and by immunono-electron microscopy (EM). Compared to HIV- cases, in HIV+ cases, there was abundant intracellular Abeta immunostaining in pyramidal neurons and along axonal tracts. Cases with HIV encephalitis (HIVE) had higher levels of intraneuronal Abeta immunoreactivity compared to HIV+ cases with no HIVE. Moreover, levels of intracellular Abeta correlated with age in the group with HIVE. Double-labeling analysis showed that the Abeta-immunoreactive granules in the neurons co-localized with lysosomal markers such as cathepsin-D and LC3. Ultrastructural analysis by immuno-EM has confirmed that in these cases, intracellular Abeta was often found in structures displaying morphology similar to autophagosomes. These findings suggest that long-term survival with HIV might interfere with clearance of proteins such as Abeta and worsen neuronal damage and cognitive impairment in this population.

Molecular pathology of neuro-AIDS (CNS-HIV)

The cognitive deficits in patients with HIV profoundly affect the quality of life of people living with this disease and have often been linked to the neuro-inflammatory condition known as HIV encephalitis (HIVE). With the advent of more effective anti-retroviral therapies, HIVE has shifted from a sub-acute to a chronic condition. The neurodegenerative process in patients with HIVE is characterized by synaptic and dendritic damage to pyramidal neurons, loss of calbindin-immunoreactive interneurons and myelin loss. The mechanisms leading to neurodegeneration in HIVE might involve a variety of pathways, and several lines of investigation have found that interference with signaling factors mediating neuroprotection might play an important role. These signaling pathways include, among others, the GSK3beta, CDK5, ERK, Pyk2, p38 and JNK cascades. Of these, GSK3beta has been a primary focus of many previous studies showing that in infected patients, HIV proteins and neurotoxins secreted by immune-activated cells in the brain abnormally activate this pathway, which is otherwise regulated by growth factors such as FGF. Interestingly, modulation of the GSK3beta signaling pathway by FGF1 or GSK3beta inhibitors (lithium, valproic acid) is protective against HIV neurotoxicity, and several pilot clinical trials have demonstrated cognitive improvements in HIV patients treated with GSK3beta inhibitors. In addition to the GSK3beta pathway, the CDK5 pathway has recently been implicated as a mediator of neurotoxicity in HIV, and HIV proteins might activate this pathway and subsequently disrupt the diverse processes that CDK5 regulates, including synapse formation and plasticity and neurogenesis. Taken together, the GSK3beta and CDK5 signaling pathways are important regulators of neurotoxicity in HIV, and modulation of these factors might have therapeutic potential in the treatment of patients suffering from HIVE. In this context, the subsequent sections will focus on reviewing the involvement of the GSK3beta and CDK5 pathways in neurodegeneration in HIV.

Differential expression of immunophilins FKBP51 and FKBP52 in the frontal cortex of HIV-infected patients with major depressive disorder

Patients infected with human immunodeficiency virus (HIV) have a higher risk of developing major depressive disorder (MDD) than the general population. Immunophilins FKBP51 and FKBP52 are expressed in cortical neurons and regulate the function of the glucocorticoid receptor (GR). Previous reports have shown that genetic variants in the FKBP5 gene encoding FKBP51 are linked to psychiatric disorders. We sought to determine whether immunophilins are upregulated in HIV infection. To determine whether FKBP52 and FKBP51 are associated with MDD and/or HIV, we compared protein and gene expression in autopsy tissues from the frontal cortical gray matter. The study cases were divided into five groups: control, MDD, MDD with psychosis, HIV(+), and HIV(+) with MDD. Gene expression and protein levels were determined by real-time PCR and Western blot analysis of fresh frozen tissues. Genotyping of previously published alleles of the FKBP5 gene was also performed. We found correlation of upregulation of both immunophilins in the HIV-infected groups. In the HIV(+) population with MDD, FKBP4 expression is significantly higher while FKBP5 is more variable. After analyzing the FKBP5 gene for single nucleotide polymorphisms, we found that rs3800373 CC genotype is more frequent in the MDD and MDD/Psychosis groups. We hypothesized that the levels of FKBP51, as modulator of the nuclear translocation of GR, would be lower in MDD. Instead, an increase in FKBP51 at both the transcript (FKBP5) and protein level correlated with MDD. Increased FKBP4 expression of correlated to HIV(+)MDD but not to HIV without MDD.

Immunodetection of human immunodeficiency virus type 1 (HIV-1) Vpr in brain tissue of HIV-1 encephalitic patients

Human immunodeficiency virus (HIV) encephalitis (HIVE), the most severe neurological complication associated with HIV-1 infection, leads to the onset of HIV-1-associated dementia (HAD). Several HIV-1 viral proteins have been implicated in HIVE-associated neurodegeneration. HIV-1 viral protein R (Vpr), a virion associated gene product known to induce apoptosis in nonproliferating cells, including neurons, is thought to contribute to the neuropathogenesis associated with HIVE. Though current research suggests that Vpr plays a significant role in neuropathogenesis, the presence of Vpr in the brain tissue of HIVE patients has not been assessed. Using a panel of HIVE patient brain tissue, the authors have shown that Vpr is present in detectable amounts in both the basal ganglia and frontal cortex of all HIVE brain tissue samples tested. Double immunofluorescence indicated that Vpr was found in the macrophages and neurons, but not in the astrocytes, of HIVE patients. These results for the first time show the presence of Vpr in vivo and further support the role of Vpr in neuropathogenesis.

Distribution of brain HIV load in AIDS

Approximately one quarter of patients with AIDS develop severe cognitive deficits called HIV-associated dementia complex (ADC). There is some controversy regarding the importance of viral load in mediating neurologic disease. With the advent of sensitive, quantitative and reproducible RNA assays for HIV load in plasma and CSF, we quantified viral load in brains from 10 autopsied HIV-infected subjects and 2 non-infected controls. The new quantitative HIV RNA assays showed general agreement with previously used semi-quantitative immunocytochemical assessments of HIV envelope protein, and were performed without professional subjective interpretation. All cases with very high levels of HIV in the CSF, had high overall levels in the brain, suggesting that CSF viral loads exceeding 10(6) copies per mL may be a surrogate marker of high viral load in the brain. Levels of virus in the spleen showed no clear association with those found in the brain. HIV RNA was not uniformly distributed throughout the brain. Selective regions, including basal ganglia and hippocampus, showed higher levels of virus than the cerebellar cortex and mid-frontal cortical gray matter. Assessment of overall brain viral load requires careful attention to regional quantitation.

Cortical and subcortical neurodegeneration is associated with HIV neurocognitive impairment

OBJECTIVE

To determine the association of markers of regional neurodegeneration (ND) at autopsy to degree of neurocognitive impairment in persons with HIV.

DESIGN

In a prospectively followed cohort of HIV-infected individuals we examined the relationship between antemortem neuropsychological (NP) abilities and postmortem neuropathological data.

METHODS

Twenty-seven HIV-infected individuals with both neuropsychological and neuropathological data were identified. Laser confocal scanning microscopy was used to determine the degree of ND based on: (1) microtubule-associated protein (MAP2; reflecting neuronal cell bodies and dendrites) and (2) synaptophysin (SYN; a measure of presynaptic terminals). A regional combined score, based on the distribution of percentage neuropil occupied by MAP2 and SYN and emphasizing severity of ND, was created for each brain region: midfrontal cortex, hippocampus, and putamen.

RESULTS

The regional combined scores from each brain region studied were better correlated with level of global NP impairment than measures of SYN and MAP2 individually. In a regression, hippocampal and putamen regional combined scores were independent predictors of degree of antemortem NP impairment (F(3,23) = 6.17; P < 0.01; R2 = 0.45). The correlations among regional ND measures demonstrated that ND is unevenly distributed across multiple brain regions.

CONCLUSIONS

As the anatomic distribution and temporal progression of neuropathologic changes appears to differ across individuals, it is important to consider both cortical and subcortical brain regions in studies of neuropathogenesis and treatment of HIV-related brain disease. Furthermore, combining information from several markers of neural injury provided the strongest association with degree of neurocognitive impairment during life.

Brain deposition of beta-amyloid is a common pathologic feature in HIV positive patients

BACKGROUND

We planned to analyze the prevalence and distribution of beta-amyloid deposition in the HIV+ brain in the HAART era. Our working hypothesis is that long term survival, aging and the secondary effects of HAART may contribute to increased beta-amyloid accumulation in this patient population.

METHODS

Paraffin embedded archival brain autopsy tissues were assessed by immunocytochemistry for beta-amyloid. Detailed in-vivo neuro-behavioral assessments and ApoE genotyping were available for a subset of the studied population.

RESULTS

Immunoreactivity with the antibodies 4G8 and 6E10 was found predominantly in neuronal soma and dystrophic axonal processes. Extracellular, often perivascular plaques were also identified in many cases.

CONCLUSIONS

We propose that prolonged HAART and aging may contribute to an overall increase in amyloid deposition, potentially mediated by inhibition of insulin degradation enzyme (IDE) or disruption of the axonal transport of the amyloid precursor protein.

Immunophilin expression in the HIV-infected brain

Immunophilins (IP) are receptors for immunosuppressive drugs and also aid protein folding, assembly, and trafficking. This autopsy study analyses the levels of FKBP12 in the brain of patients with HIV encephalitis. We show that the expression of FKBP12 is increased in the deep gray matter and frontal cortex where it colocalizes with markers of pathology. Changes in FKBP12 levels may be linked to the abnormal protein folding and axonal transport that characterize the neurodegenerative process and could also explain the selective vulnerability of the basal ganglia to HIV infection.