Neurological complications of HIV infection

The Repeatable Battery for the Assessment of Neuropsychological Status as a screening strategy for HIV-Associated Neurocognitive Disorders

HIV-infected people are at risk for neurocognitive impairment (HIV-Associated Neurocognitive Disorders - HAND). To evaluate whether the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), a widely used neurocognitive screening tool, could be a valid instrument for HAND identification, we evaluated 166 HIV-infected subjects. Our results showed that 96 (57.8%) HIV-infected scored RBANS Total Index Score <85 (at least one SD below the normal), 12 (7.2%) of them scored RBANS Total Index Score <70 (at least 2 SD below the normal, indicating a possible HIV-Associated Dementia). The more compromised areas were Immediate and Delayed Memory, and Attention. In the group with RBANS Total Index Score <85, there were significantly lower scores of Mini Mental State Examination (P = 0.0008), Clock Drawing Test (P = 0.0015) and higher score of Geriatric Depression Scale (P = 0.02) compared to the RBANS Total Index Score ≥85 group. Using a stepwise logistic regression, considering RBANS Total Index Score as dependent variable, we found a positive interaction with tenofovir/emtricitabine assumption (P = 0.027), Clock Drawing Test (P = 0.0125) and educational level (P = 0.0054). Being the viro-immunological markers not capable of predicting cognitive decline in HIV-infected individuals, our data suggest that RBANS may be a valid tool for the early identification of HIV-related cognitive impairment.

Biology of the human blood-nerve barrier in health and disease

A highly regulated endoneurial microenvironment is required for normal axonal function in peripheral nerves and nerve roots, which structurally consist of an outer collagenous epineurium, inner perineurium consisting of multiple concentric layers of specialized epithelioid myofibroblasts that surround the innermost endoneurium, which consists of myelinated and unmyelinated axons embedded in a looser mesh of collagen fibers. Endoneurial homeostasis is achieved by tight junction-forming endoneurial microvessels that control ion, solute, water, nutrient, macromolecule and leukocyte influx and efflux between the bloodstream and endoneurium, and the innermost layers of the perineurium that control interstitial fluid component flux between the freely permeable epineurium and endoneurium. Strictly speaking, endoneurial microvascular endothelium should be considered the blood-nerve barrier (BNB) due to direct communication with circulating blood. The mammalian BNB is considered the second most restrictive vascular system after the blood-brain barrier (BBB) based on classic in situ permeability studies. Structural alterations in endoneurial microvessels or interactions with hematogenous leukocytes have been described in several human peripheral neuropathies; however major advances in BNB biology in health and disease have been limited over the past 50 years. Guided by transcriptome and proteome studies of normal and pathologic human peripheral nerves, purified primary and immortalized human endoneurial endothelial cells that form the BNB and leukocytes from patients with well-characterized peripheral neuropathies, validated by in situ or ex vivo protein expression studies, data are emerging on the molecular and functional characteristics of the human BNB in health and in specific peripheral neuropathies, as well as chronic neuropathic pain. These early advancements have the potential to not only increase our understanding of how the BNB works and adapts or fails to adapt to varying insult, but provide insights relevant to pathogenic leukocyte trafficking, with translational potential and specific therapeutic application for chronic peripheral neuropathies and neuropathic pain.

Insights into the Gene Expression Profiles of Active and Restricted Red/Green-HIV+ Human Astrocytes: Implications for Shock or Lock Therapies in the Brain

A significant number of people living with human immunodeficiency virus type 1 (HIV-1) suffer from HIV-associated neurocognitive disorders (HAND). Many previous studies investigating HIV in astrocytes as a heterogenous population have established the relevance of astrocytes to HIV-associated neuropathogenesis. However, these studies were unable to differentiate the state of infection, i.e., active or latent, or to evaluate how this affects astrocyte biology. In this study, the pseudotyped doubly labeled fluorescent reporter red/green (R/G)-HIV-1 was used to identify and enrich restricted and active populations of HIV⁺ astrocytes based on the viral promoter activity. Here, we report that the majority of human astrocytes restricted R/G-HIV-1 gene expression early during infection and were resistant to reactivation by vorinostat and interleukin 1β. However, actively infected astrocytes were inducible, leading to increased expression of viral proteins upon reactivation. R/G-HIV-1 infection also significantly decreased the cell proliferation and glutamate clearance ability of astrocytes, which may contribute to excitotoxicity. Moreover, transcriptome analyses to compare gene expression patterns of astrocyte harboring active versus restricted long terminal repeats (LTRs) revealed that the gene expression patterns were similar and that the active population demonstrated more widespread and robust changes. Our data suggest that harboring the HIV genome profoundly alters astrocyte biology and that strategies that keep the virus latent (e.g., block and lock) or those that reactivate the latent virus (e.g., shock and kill) would be detrimental to astrocyte function and possibly augment their contributions to HAND.IMPORTANCE More than 36 million people are living with HIV-1 worldwide, and despite antiretroviral therapy, 30 to 50% of the people living with HIV-1 suffer from mild to moderate neurocognitive disorders. HIV-1 reservoirs in the central nervous system (CNS) are challenging to address due to low penetration of antiretroviral drugs, lack of resident T cells, and permanent integration of provirus into neural cells such as microglia and astrocytes. Several studies have shown astrocyte dysfunction during HIV-1 infection. However, little is known about how HIV-1 latency affects their function. The significance of our research is in identifying that the majority of HIV⁺ astrocytes restrict HIV expression and were resistant to reactivation. Further, simply harboring the HIV genome profoundly altered astrocyte biology, resulting in a proinflammatory phenotype and functional changes. In this context, therapeutic strategies to reactivate or silence astrocyte HIV reservoirs, without excising proviral DNA, will likely lead to detrimental neuropathological outcomes during HIV CNS infection.

Tanshinone IIA Alleviates CCL2-Induced Leaning memory and Cognition Impairment in Rats: A Potential Therapeutic Approach for HIV-Associated Neurocognitive Disorder

Chemokine CC motif ligand 2 (CCL2) is one of the most recognized proinflammatory chemokines, and the expression of CCL2 in the cerebrospinal fluid of patients infected with HIV-1 is significantly higher than that of healthy people. As such, it is seen as an important cause of HIV-associated neurocognitive disorder (HAND). Our previous investigation has confirmed the pathological role of CCL2 in mediating brain damage leading to cognitive dysfunction. Currently, however, research on therapeutic drugs for the central nervous system targeting CCL2 is very limited. Our present study used brain stereotactic technology to induce cognitive impairment in rats by injecting CCL2 (5 ng) into the bilateral hippocampus. To investigate the protective effect and mechanism of Tanshinone IIA (25, 50, 75 mg/kg/d) on CCL2-induced learning memory and cognitive impairment in rats, we performed the Morris water maze (MWM) and novel object recognition tests (NORT) on the rats. The results showed that Tanshinone IIA significantly alleviated CCL2-induced learning memory and cognitive dysfunction. Further studies on the hippocampal tissue of the rats revealed that Tanshinone IIA treatment significantly increased the activity of SOD and GSH-Px while the level of MDA decreased compared to the model group. Additionally, the relative expression of apoptosis-associated genes caspase-3, caspase-8, and caspase-9 and inflammation-associated genes IL-1β and IL-6 in Tanshinone IIA-treated rats was lower than that in model rats. Finally, we confirmed hippocampal neuron loss and apoptosis by Nissl staining and TdT-mediated dUTP Nick end labeling (TUNEL). Taken together, these data imply that Tanshinone IIA can ameliorate CCL2-induced learning memory and cognitive impairment by impacting oxidative stress, inflammation, and apoptosis. Tanshinone IIA may be a potential therapeutic agent for the treatment of HAND.

HIV: Biology to Treatment

AIDS is one of the most dreaded diseases of the twenty-first century caused by human immunodeficiency virus (HIV). Recently, there are reports which show decline in new infections due to better access to anti-retroviral drugs. Still on a daily basis, ~2356 new HIV infections are being reported globally. New treatments and anti-HIV drugs are being continuously developed with the aim to control and cure AIDS. The anti-HIV drugs that are in use usually target HIV entry and replication inside the host cells. However, these drugs are only partially effective in slowing the rate of HIV replication. Nevertheless, the virus manages to replicate at much slower rates even when anti-retroviral treatment is ongoing. The HIV seropositives who are on anti-retroviral treatment for long periods of time are now developing different kinds of other complications including neuroAIDS. The latest development in HIV therapy is a novel kind of bone marrow transplantation from donors who have a homozygous mutation in CCR5 gene.

Prevalence of perinatal depression among HIV-positive women: a systematic review and meta-analysis

BACKGROUND

Increasing attention has been paid to differences in the prevalence of perinatal depression by HIV status, although inconsistent results have been reported. The aim of this systematic review and meta-analysis was to assess the relationship between perinatal depression and HIV infection. A comprehensive meta-analysis of comparative studies comparing the prevalence of antenatal or postnatal depression between HIV-infected women and HIV-negative controls was conducted.

METHODS

Studies were identified through PubMed/Medline, Scopus, Web of Science, Cochrane Library, Embase and PsycINFO, and the reading of complementary references in August 2019. Subgroup analyses were performed for anticipated explanation of heterogeneity using methodological quality and pre-defined study characteristics, including study design, geographical location and depression screening tools for depression. The overall odds ratio (OR) and mean prevalence of each group were calculated.

RESULTS

Twenty-three studies (from 21 publications), thirteen regarding antenatal depression and ten regarding postnatal depression were included, comprising 3165 subjects with HIV infection and 6518 controls. The mean prevalence of antenatal depressive symptoms in thirteen included studies was 36% (95% CI: 27, 45%) in the HIV-positive group and 26% (95% CI: 20, 32%) in the control group. The mean prevalence of postnatal depressive symptoms in ten included studies was 21% (95% CI: 14, 27%) in the HIV-positive group and 16% (95% CI: 10, 22%) in the control group. Women living with HIV have higher odds of antenatal (OR: 1.42; 95% CI: 1.12, 1.80) and postnatal depressive symptoms (OR: 1.58; 95% CI: 1.08, 2.32) compared with controls. Publication bias and moderate heterogeneity existed in the overall meta-analysis, and heterogeneity was partly explained by the subgroup analyses.

CONCLUSIONS

Women with HIV infection exhibit a significantly higher OR of antenatal and postnatal depressive symptoms compared with controls. For the health of both mother and child, clinicians should be aware of the significance of depression screening before and after delivery in this particular population and take effective measures to address depression among these women.

The Neurocognitive Assessment in the Metabolic and Aging Cohort (NAMACO) study: baseline participant profile

Objectives

The aim of the study was to examine baseline neurocognitive impairment (NCI) prevalence and factors associated with NCI among patients enrolled in the Neurocognitive Assessment in the Metabolic and Aging Cohort (NAMACO) study.

Methods

The NAMACO study is an ongoing, prospective, longitudinal, multicentre and multilingual (German, French and Italian) study within the Swiss HIV Cohort Study. Between 1 May 2013 and 30 November 2016, 981 patients ≥ 45 years old were enrolled in the study. All underwent standardized neuropsychological (NP) assessment by neuropsychologists. NCI was diagnosed using Frascati criteria and classified as HIV‐associated or as related to other factors. Dichotomized analysis (NCI versus no NCI) and continuous analyses (based on NP test z‐score means) were performed.

Results

Most patients (942; 96.2%) had viral loads < 50 HIV‐1 RNA copies/mL. NCI was identified in 390 patients (39.8%): 263 patients (26.8%) had HIV‐associated NCI [249 patients (25.4%) had asymptomatic neurocognitive impairment (ANI)] and 127 patients (13%) had NCI attributable to other factors, mainly psychiatric disorders. There was good correlation between dichotomized and continuous analyses, with NCI associated with older age, non‐Caucasian ethnicity, shorter duration of education, unemployment and longer antiretroviral therapy duration.

Conclusions

In this large sample of aging people living with HIV with well‐controlled infection in Switzerland, baseline HIV‐associated NCI prevalence, as diagnosed after formal NP assessment, was 26.8%, with most cases being ANI. The NAMACO study data will enable longitudinal analyses within this population to examine factors affecting NCI development and course.

Peripheral neuropathy in patients with human immunodeficiency viral infection at a tertiary hospital in Ghana

Peripheral neuropathy (PN) is the most frequent neurological complication in people living with HIV/AIDS. Neurological damage was identified to not only be caused by the viral infection itself but also through neurotoxic antiretroviral therapy (ART). PN is associated with a variety of risk factors; however, detailed knowledge is scarce for sub-Saharan African populations, bearing among the highest HIV/AIDS infection burden.In a cross-sectional study, we assessed the prevalence of PN in 525 adult outpatients suffering from HIV/AIDS and admitted to the largest tertiary hospital in Ghana. Through a detailed questionnaire and clinical examination including neurologic assessment and laboratory blood sample testing, this study investigated associations of PN with demographic and health determinants and identified risk factors associated with sensory neuropathy.The prevalence of PN in the Ghanaian cohort was 17.7% and increased odd ratios (OR) when patients were taller (> 1.57 m; OR = 3.84; 95% CI 1.38-10.66) or reached the age > 34 years (p = 0.124). Respondents with longer education duration had significantly less PN (≥ 9 years of education; OR = 0.49; 95% CI 0.26-0.92). The study also identified significant association of PN to both waist and hip girth and neutrophil counts. Curiously, higher adjusted odd ratios (aOR) of PN of patients under ART treatment were observed when CD4 lymphocytes were elevated (aOR = 0.81; 95% CI 0.36-1.83 and aOR = 2.17; 95% CI 0.93-5.05, for 300 and 600 counts, respectively). For patients on ART, an increase of 10 CD4 cell count units increased their chance of developing PN by 1% (aOR = 1.01; 95% CI 1.00 to 1.03).Despite current drug application regulations, prevalence of PN is still unacceptably high in sub-Saharan African populations. Reduction in chronic morbidity through a health system with routine monitoring, early diagnosis and prompt intervention, and effective case management can improve people living with HIV/AIDS' quality of life.

Cerebral Multishell Diffusion Imaging Parameters are Associated with Blood Biomarkers of Disease Severity in HIV Infection

BACKGROUND AND PURPOSE

HIV-positive subjects suffer from neurocognitive deficits and disorder. We employ multishell diffusion imaging to investigate possible white matter microstructural correlates of infection severity, quantified through plasmatic percentage value of CD4 T-lymphocytes, Nadir-CD4 count, and plasma concentration of human immunodeficiency virus (HIV)-ribonucleic acid (RNA).

METHODS

A total of 41 HIV patients underwent magnetic resonance imaging (MRI) and blood sampling to evaluate biochemical markers. Diffusion-weighted imaging was performed at 3 Tesla (b-values: 1000 s/mm² and 2500 s/mm², 64 gradient directions/b-value, 8 b0 images). The Diffusion Tensor Imaging and Diffusional Kurtosis Imaging models were fitted separately after which mean, radial, and axial diffusivity (MD, RD, AD, respectively), fractional anistrotropy (FA), mean and radial kurtosis (MK and RK, respectively), and kurtosis anisotropy (KA) maps were extracted. Associations of each metric with biochemical markers were explored through tract-based spatial statistics followed by threshold-free cluster enhancement.

RESULTS

We found significant positive associations between Nadir-CD4 values and both KA and FA, and significant negative associations between Nadir-CD4 values and MD. Also, we found significant positive associations among %CD4 and MK, KA, and FA, and significant negative associations among %CD4 values and MD. These associations were bilateral and involved predominantly the long association fibers. Anatomically, these associations were more widespread when using KA as compared to FA. No statistically significant associations with HIV-RNA concentrations were found.

CONCLUSIONS

In HIV-positive subjects, associations between biochemical and diffusion-MRI variables are found along the association fibers, which connect brain areas involved in memory formation, providing a possible interpretation for the neurobiological substrate underlying cognitive disturbances in HIV.

Neurological manifestations, laboratory and neuroimaging features in HIV-infected patients

Objectives:

To present detailed information regarding these aspects in Human Immunodeficiency Virus (HIV)-infected patients making an effort to improve the recognition of neurological complications of HIV infection.

Methods:

This retrospective study analyzed the clinical manifestations, laboratory and neuroimaging results of HIV-infected patients with neurological complications at Xuanwu hospital, Beijing, China from January 2011 to December 2014, one of top-rated hospitals in Beijing, China.

Results:

A diverse range of clinical diagnoses was identified, including encephalopathy, meningoencephalitis, peripheral neuropathy, multiple sclerosis, cerebral infarction and lymphoma associated with HIV infection. The mostly observed neurological disorders were motor/sensory deficits in the limbs (75%), cognitive impairments (42%) and fever (33%). Non-specific results of laboratory tests, including elevated erythrocyte sedimentation rate (ESR), cerebrospinal fluid (CSF) protein concentration and IgG, were found. Brain Magnetic Resonance Imaging (MRI) abnormalities displayed a variety of patterns and distributions due to diverse clinical profiles.

Conclusion:

The clinical scenarios of HIV-infected patients are remarkably diverse and complex. Etiological tests would be cardinal to make more definitive diagnosis for HIV-infected patients. Prospective studies with follow-up were needed to bring more accurate information.

Clinical care of patients with HIV

There has been a significant change in the clinical characteristics of people living with HIV, with new needs arising that must be tackled. The life expectancy of a subject diagnosed early with HIV infection and recei-ving suppressive antiretroviral therapy is currently on a par with the life expectancy of the general popula-tion. HIV is now a chronic treatable disease and requires a multidisciplinary approach that includes both the hospital medicine specialties and primary care physicians. The fragmented model to provide social and medical healthcare hinders the proper management of patients with HIV infection. There is significant clinical and geographical variability in the healthcare provided for HIV infection in Spain and the need to define and implement new models of healthcare delivery for this disease has been identified.

Rice Yellow Stunt Nucleorhabdovirus Matrix Protein Mediates Viral Axonal Transport in the Central Nervous System of Its Insect Vector

Persistently transmitted plant viruses encounter multiple membrane and tissue barriers in the process of completing their infection routes within their insect vectors. Some of these viruses have been reported to overcome the elaborate barriers of the central nervous system (CNS) to travel through the nervous tissues, but the specific mechanisms of this process remain unknown. Here, we report the axonal transport mechanism of rice yellow stunt virus (RYSV), a nucleorhabdovirus, in the CNS of the green rice leafhopper (Nephotettix cincticeps). The infection route of RYSV in the internal organs of its insect vector after ingestion of the virus was investigated by immunofluorescence microscopy. RYSV was first detected in the epithelial cells of midgut regions, from where it proceeded to the nervous system, and finally into the salivary glands. We then utilized immunofluorescence and electron microscopy to investigate the distribution of RYSV particles within the leafhopper CNS, demonstrating that non-enveloped viral particles distributed along the microtubule-based neurofilaments in the axon cytoplasm following the direct interaction of leafhopper α-tubulin with the RYSV M protein. Tubulin inhibitors inhibited the dissemination of RYSV to the CNS, then into the salivary glands in leafhoppers. We therefore describe a mechanism of plant virus transport through CNS axons as an alternative means of rapid viral dissemination in an insect vector.

Role of the inflammasomes in HIV-associated neuroinflammation and neurocognitive disorders

HIV associated neurocognitive disorders (HAND) is a unique form of neurological impairment that stems from HIV. This disease and its characteristics can be accredited to incorporation of DNA and mRNA of HIV-1 into the CNS. A proper understanding of the intricacies of HAND and the underlying mechanisms associated with corresponding immune reactions are vital for the potential development of a reliable treatment for HAND. A common phenomenon observed in CNS cells, specifically microglia, that are infected with HAND is inflammation, which is a consequence of the activation of innate immune response due to a variety of stimuli, in this case, being the HIV infection. The CNS based inflammation is mediated by the production of cytokines, chemokines, reactive oxygen species, and secondary messengers, which occurs at CNS glia, endothelial cells and peripherally derived immune cells. Inflammasomes play a significant role with regard to neuroinflammation due to their ability to dictate the activation of various inflammatory responses. Certain stimuli can result in the activation of caspase-1; hence, leading to the processing of interleukin-1β and interleukin-18 pro-inflammatory cytokines. The processed IL-1β and IL-18 activate signaling pathways that begin the process of neuroinflammation. Due to the fact that the NLRP3 inflammasome is the most abundant in the CNS, it is the most extensively investigated inflammasome with regard to the nervous system. Due to the importance of neuroinflammation in the evolution of HAND and proliferation of neuroinflammation due to HAND, it can be concluded that there exists a relationship between HAND and inflammasomes. The aim of our review is to consolidate current knowledge of important mechanisms in HAND, specifically related to its relationship with neuroinflammation and inflammasomes to shed light on a possible improved treatment for HAND.

Low-frequency fluctuation characteristics in rhesus macaques with SIV infection: a resting-state fMRI study

Simian immunodeficiency virus (SIV)-infected macaque is a widely used model to study human immunodeficiency virus. The purpose of the study is to discover the amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF) changes in SIV-infected macaques. Seven rhesus macaques were involved in the longitudinal MRI scans: (1) baseline (healthy state); (2) SIV infection stage (12 weeks after SIV inoculation). ALFF and fALFF were subsequently computed and compared to ascertain the changes caused by SIV infection. Whole-brain correlation analysis was further used to explore the possible associations between ALFF/fALFF values and immune status parameters (CD4+ T cell counts, CD4/CD8 ratio and virus load). Compared with the baseline, macaques in SIV infection stage displayed strengthened ALFF values in left precuneus, postcentral gyrus, and temporal gyrus, and weakened ALFF values in orbital gyrus and inferior temporal gyrus. Meanwhile, increased fALFF values were found in left superior frontal gyrus, right precentral gyrus, and superior temporal gyrus, while decreased fALFF values existed in left hippocampus, left caudate, and right inferior frontal gyrus. Furthermore, ALFF and fALFF values in several brain regions showed significant relationships with CD4+ T cell counts, CD4/CD8 ratio, and plasma virus load. Our findings could promote the understanding of neuroAIDS caused by HIV infection, which may provide supplementary evidences for the future therapy study in SIV model.

Neuropathogenesis of human immunodeficiency virus infection

Human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) remain a common end-organ manifestation of viral infection. Subclinical and mild symptoms lead to neurocognitive and behavioral abnormalities. These are associated, in part, with viral penetrance and persistence in the central nervous system. Infections of peripheral blood monocytes, macrophages, and microglia are the primary drivers of neuroinflammation and neuronal impairments. While current antiretroviral therapy (ART) has reduced the incidence of HIV-associated dementia, milder forms of HAND continue. Depression, comorbid conditions such as infectious liver disease, drugs of abuse, antiretroviral drugs themselves, age-related neurodegenerative diseases, gastrointestinal maladies, and concurrent social and economic issues can make accurate diagnosis of HAND challenging. Increased life expectancy as a result of ART clearly creates this variety of comorbid conditions that often blur the link between the virus and disease. With the discovery of novel biomarkers, neuropsychologic testing, and imaging techniques to better diagnose HAND, the emergence of brain-penetrant ART, adjunctive therapies, longer life expectancy, and better understanding of disease pathogenesis, disease elimination is perhaps a realistic possibility. This review focuses on HIV-associated disease pathobiology with an eye towards changing trends in the face of widespread availability of ART.

Designing robot-assisted neurorehabilitation strategies for people with both HIV and stroke

There is increasing evidence that HIV is an independent risk factor for stroke, resulting in an emerging population of people living with both HIV and stroke all over the world. However, neurorehabilitation strategies for the HIV-stroke population are distinctly lacking, which poses an enormous global health challenge. In order to address this gap, a better understanding of the HIV-stroke population is needed, as well as potential approaches to design effective neurorehabilitation strategies for this population. This review goes into the mechanisms, manifestations, and treatment options of neurologic injury in stroke and HIV, the additional challenges posed by the HIV-stroke population, and rehabilitation engineering approaches for both high and low resource areas. The aim of this review is to connect the underlying neurologic properties in both HIV and stroke to rehabilitation engineering. It reviews what is currently known about the association between HIV and stroke and gaps in current treatment strategies for the HIV-stroke population. We highlight relevant current areas of research that can help advance neurorehabilitation strategies specifically for the HIV-stroke population. We then explore how robot-assisted rehabilitation combined with community-based rehabilitation could be used as a potential approach to meet the challenges posed by the HIV-stroke population. We include some of our own work exploring a community-based robotic rehabilitation exercise system. The most relevant strategies will be ones that not only take into account the individual status of the patient but also the cultural and economic considerations of their respective environment.

Persistent EcoHIV infection induces nigral degeneration in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-intoxicated mice

The widespread use of antiretroviral therapy for treatment of human immunodeficiency virus (HIV) infections has dramatically improved the quality and duration of life for HIV-positive individuals. Despite this success, HIV persists for the life of an infected person in tissue reservoirs including the nervous system. Thus, whether HIV exacerbates age-related brain disorders such as Parkinson's disease (PD) is of concern. In support of this idea, HIV infection can be associated with motor and gait abnormalities that parallel late-stage manifestations of PD including dopaminergic neuronal loss. With these findings in hand, we investigated whether viral infection could affect nigrostriatal degeneration or exacerbate chemically induced nigral degeneration. We now demonstrate an additive effect of EcoHIV on dopaminergic neuronal loss and neuroinflammation induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intoxication. HIV-1-infected humanized mice failed to recapitulate these EcoHIV results suggesting species-specific neural signaling. The results demonstrate a previously undefined EcoHIV-associated neurodegenerative response that may be used to model pathobiological aspects of PD.

Neuropsychological phenotypes among men with and without HIV disease in the multicenter AIDS cohort study

OBJECTIVE

Mild forms of HIV-associated neurocognitive disorder (HAND) remain prevalent in the combination antiretroviral therapy (cART) era. This study's objective was to identify neuropsychological subgroups within the Multicenter AIDS Cohort Study (MACS) based on the participant-based latent structure of cognitive function and to identify factors associated with subgroups.

DESIGN

The MACS is a four-site longitudinal study of the natural and treated history of HIV disease among gay and bisexual men.

METHODS

Using neuropsychological domain scores, we used a cluster variable selection algorithm to identify the optimal subset of domains with cluster information. Latent profile analysis was applied using scores from identified domains. Exploratory and posthoc analyses were conducted to identify factors associated with cluster membership and the drivers of the observed associations.

RESULTS

Cluster variable selection identified all domains as containing cluster information except for Working Memory. A three-profile solution produced the best fit for the data. Profile 1 performed below average on all domains, Profile 2 performed average on executive functioning, motor, and speed and below average on learning and memory, Profile 3 performed at or above average across all domains. Several demographic, cognitive, and social factors were associated with profile membership; these associations were driven by differences between Profile 1 and the other profiles.

CONCLUSION

There is an identifiable pattern of neuropsychological performance among MACS members determined by all domains except Working Memory. Neither HIV nor HIV-related biomarkers were related with cluster membership, consistent with other findings that cognitive performance patterns do not map directly onto HIV serostatus.

Konzo: a distinct neurological disease associated with food (cassava) cyanogenic poisoning

Epidemics of neurodegenerative diseases putatively caused by food toxins have been reported in the tropics with no clear understanding of their pathogenetic mechanisms. These diseases include the disease named Konzo that has been well documented in sub-Sahara Africa, mostly among children and women of childbearing age. Outbreaks of Konzo have occurred in the Democratic Republic of Congo, Mozambique, Tanzania, Central African Republic, Angola, Cameroun, and most recently in Zambia. The main clinical picture consists of a symmetrical, permanent and irreversible spastic paraparesis (motor neuron disease) with no signs of sensory or genitourinary impairments. Recently, cognitive impairments and neurodevelopmental delays have been reported among school-aged and very young children. The exact pathogenetic mechanisms of the disease remain unknown. Epidemiological studies consistently show an association between outbreaks of the disease and chronic dietary reliance on insufficiently processed cyanogenic cassava (manioc or tapioca). Biochemical and toxicological studies suggest that the metabolites of linamarin (α-Hydroxyisobutyronitrile β-D-glucopyranoside, the main cassava cyanogen), notably cyanide (mitochondrial toxin), thiocyanate (AMPA chaotropic agent), and cyanate (protein carbamoylating agent) may play an important role in the pathogenesis of Konzo. Experimental data suggest that thiol-redox and protein- folding mechanisms may also be perturbed. Factors of susceptibility including genetics, poor nutrition, poverty and dietary cyanogen exposure, or their interactions have been suggested. Serological studies have ruled out the role of retroviruses such as the human lymphotropic viruses HIV-I/II or HTLV-I/II. Because there is no cure for Konzo, prevention of the disease remains of paramount importance. Prospects for cognitive rehabilitation still need to be explored and tested.

2017 HIVMA of IDSA Clinical Practice Guideline for the Management of Chronic Pain in Patients Living With HIV

Pain has always been an important part of human immunodeficiency virus (HIV) disease and its experience for patients. In this guideline, we review the types of chronic pain commonly seen among persons living with HIV (PLWH) and review the limited evidence base for treatment of chronic noncancer pain in this population. We also review the management of chronic pain in special populations of PLWH, including persons with substance use and mental health disorders. Finally, a general review of possible pharmacokinetic interactions is included to assist the HIV clinician in the treatment of chronic pain in this population.It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. The Infectious Diseases Society of American considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Cognitive Function Among Antiretroviral Treatment-Naive Individuals Infected With Human Immunodeficiency Virus Type 1 Subtype G Versus CRF02_AG in Nigeria

Background

Human immunodeficiency virus type 1 (HIV-1) subtype has been shown to be associated with disease progression. We compared cognitive function between individuals infected with HIV-1 subtype G and CRF02_AG in Nigeria.

Methods

For this cross-sectional study, samples were analyzed from 146 antiretroviral-naive participants. Genotypic analysis of plasma HIV RNA was performed by nested polymerase chain reaction of protease and reverse transcriptase genes, and sequences were aligned with curated HIV-1 subtype references. Cognitive status was determined using demographically adjusted T scores and global deficit score (GDS) obtained from a comprehensive neuropsychological test battery.

Results

A total of 76 (52.1%) participants were infected with CRF02_AG, 48 (32.8%) with subtype G, and 22 (15.1%) with other HIV-1 strains. In a multivariable linear regression adjusting for plasma HIV RNA, CD4 count, and depression score, mean global T score was lower among subtype G-infected compared with CRF02_AG-infected participants (mean difference, -3.0 [95% confidence interval {CI}, -5.2, to -.7]; P = .011). Also, T scores were significantly lower among subtype G- than CRF02_AG-infected participants for the speed of information processing, executive function, and verbal fluency ability domains. Adjusting for similar variables in a logistic regression, the odds of global cognitive impairment (GDS ≥0.5) were 2.2 times higher among subtype G compared with CRF02_AG-infected participants (odds ratio, 2.2 [95% CI, .9-5.4]; P = .078).

Conclusions

Cognitive performance was significantly worse among antiretroviral-naive individuals with HIV-1 subtype G vs CRF02_AG infection. Further studies are required to characterize the mechanistic basis for these differences.

Cerebellar degeneration and progressive ataxia associated with HIV-virus infection

INTRODUCTION

The spectrum of neurologic disorders associated with HIV infection is very broad, resulting from direct virus invasion, opportunistic infections, malignancies and toxic effects of drugs.

METHODS

Among a large cohort of ataxia patients (N = 1050) evaluated between 2008 and 2017, we detected four patients with HIV-infection who developed a pure progressive cerebellar ataxia syndrome combined with cerebellar atrophy.

RESULTS

Adverse drug effects, opportunistic infections and malignancies as well as immune-reconstitution syndrome were ruled out based on history and laboratory data. The exact pathophysiological mechanisms of ataxia in HIV patients is not very clear, but seems to be immune-mediated or a direct neurotoxic virus effect leading to apoptosis of Purkinje and granular cells.

CONCLUSION

HIV infection should be investigated in adult patients with undetermined sporadic progressive pure ataxia with cerebellar atrophy.

HIV and the Macrophage: From Cell Reservoirs to Drug Delivery to Viral Eradication

Macrophages serve as host cells, inflammatory disease drivers and drug runners for human immunodeficiency virus infection and treatments. Low-level viral persistence continues in these cells in the absence of macrophage death. However, the cellular microenvironment changes as a consequence of viral infection with aberrant production of pro-inflammatory factors and promotion of oxidative stress. These herald viral spread from macrophages to neighboring CD4⁺ T cells and end organ damage. Virus replicates in tissue reservoir sites that include the nervous, pulmonary, cardiovascular, gut, and renal organs. However, each of these events are held in check by antiretroviral therapy. A hidden and often overlooked resource of the macrophage rests in its high cytoplasmic nuclear ratios that allow the cell to sense its environment and rid it of the cellular waste products and microbial pathogens it encounters. These phagocytic and intracellular killing sensing mechanisms can also be used in service as macrophages serve as cellular carriage depots for antiretroviral nanoparticles and are able to deliver medicines to infectious disease sites with improved therapeutic outcomes. These undiscovered cellular functions can lead to reductions in persistent infection and may potentially facilitate the eradication of residual virus to eliminate disease.

Antidepressants for depression in adults with HIV infection

BACKGROUND

Rates of major depression among people living with HIV (PLWH) are substantially higher than those seen in the general population and this may adversely affect antiretroviral treatment outcomes. Several unique clinical and psychosocial factors may contribute to the development and persistence of depression in PLWH. Given these influences, it is unclear if antidepressant therapy is as effective for PLWH as the general population.

OBJECTIVES

To assess the efficacy of antidepressant therapy for treatment of depression in PLWH.

SEARCH METHODS

We searched The Cochrane Common Mental Disorders Group's specialised register (CCMD-CTR), the Cochrane Library, PubMed, Embase and ran a cited reference search on the Web of Science for reports of all included studies. We conducted additional searches of the international trial registers including; ClinicalTrials.gov, World Health Organization Trials Portal (ICTRP), and the HIV and AIDS - Clinical trials register. We searched grey literature and reference lists to identify additional studies and contacted authors to obtain missing data. We applied no restrictions on date, language or publication status to the searches, which included studies conducted between 1 January 1980 and 18 April 2017.

SELECTION CRITERIA

We included randomized controlled trials of antidepressant drug therapy compared to placebo or another antidepressant drug class. Participants eligible for inclusion had to be aged 18 years and older, from any setting, and have both HIV and depression. Depression was defined according to Diagnostic and Statistical Manual of Mental Disorders or International Statistical Classification of Diseases criteria.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria and extracted data. We presented categorical outcomes as risk ratios (RR) with 95% confidence intervals (CIs). Continuous outcomes were presented mean (MD) or standardized mean differences (SMD) with standard deviations (SD). We assessed quality of evidence using the GRADE approach.

MAIN RESULTS

We included 10 studies with 709 participants in this review. Of the 10 studies, eight were conducted in high income countries (USA and Italy), seven were conducted prior to 2000 and seven had predominantly men. Seven studies assessed antidepressants versus placebo, two compared different antidepressant classes and one had three arms comparing two antidepressant classes with placebo.Antidepressant therapy may result in a greater improvement in depression compared to placebo. There was a moderate improvement in depression when assessed with the Hamilton Depression Rating Scale (HAM-D) score as a continuous outcome (SMD 0.59, 95% CI 0.21 to 0.96; participants = 357; studies = 6; I² = 62%, low quality evidence). However, there was no evidence of improvement when this was assessed with HAM-D score as a dichotomized outcome (RR 1.10, 95% CI 0.89 to 1.35; participants = 434; studies = 5; I² = 0%, low quality evidence) or Clinical Global Impression of Improvement (CGI-I) score (RR 1.28, 95% CI 0.93 to 1.77; participants = 346; studies = 4; I² = 29%, low quality evidence). There was little to no difference in the proportion of study dropouts between study arms (RR 1.28, 95% CI 0.91 to 1.80; participants = 306; studies = 4; I² = 0%, moderate quality evidence).The methods of reporting adverse events varied substantially between studies, this resulted in very low quality evidence contributing to a pooled estimate (RR 0.88, 95% CI 0.64 to 1.21; participants = 167; studies = 2; I² = 34%; very low quality evidence). Based on this, we were unable to determine if there was a difference in the proportion of participants experiencing adverse events in the antidepressant versus placebo arms. However, sexual dysfunction was reported commonly in people receiving selective serotonin reuptake inhibitors (SSRIs). People receiving tricyclic antidepressants (TCAs) frequently reported anticholinergic adverse effects such as dry mouth and constipation. There were no reported grade 3 or 4 adverse events in any study group.There was no evidence of a difference in follow-up CD4 count at study termination (MD -6.31 cells/mm³, 95% CI -72.76 to 60.14; participants = 176; studies = 3; I² = 0%; low quality evidence). Only one study evaluated quality of life score (MD 3.60, 95% CI -0.38 to 7.58; participants = 87; studies = 1; very low quality evidence), due to the poor quality evidence we could not draw conclusions for this outcome.There were few studies comparing different antidepressant classes. We are uncertain if SSRIs differ from TCAs with regard to improvement in depression as evaluated by HAM-D score (MD -3.20, 95% CI -10.87 to 4.47; participants = 14; studies = 1; very low quality evidence). There was some evidence that mirtazapine resulted in a greater improvement in depression compared to an SSRI (MD 9.00, 95% CI 3.61 to 14.39; participants = 70; studies = 1; low quality evidence); however, this finding was not consistent for all measures of improvement in depression for this comparison.No studies reported on virological suppression or any other HIV specific outcomes.The studies included in this review had an overall unclear or high risk of bias due to under-reporting of study methods, high risk of attrition bias and inadequate sequence generation methods. Heterogeneity between studies and the limited number of participants, and events lead to downgrading of the quality of the evidence for several outcomes.

AUTHORS' CONCLUSIONS

This review demonstrates that antidepressant therapy may be more beneficial than placebo for the treatment of depression in PLWH. The low quality of the evidence contributing to this assessment and the lack of studies representing PLWH from generalized epidemics in low- to middle-income countries make the relevance of these finding in today's context limited. Future studies that evaluate the effectiveness of antidepressant therapy should be designed and conducted rigorously. Such studies should incorporate evaluation of stepped care models and health system strengthening interventions in the study design. In addition, outcomes related to HIV care and antiretroviral therapy should be reported.

Moyamoya syndrome in a pediatric patient with congenital human immunodeficiency virus type 1 infection resulting in intracranial hemorrhage

In the era of Antiretroviral Therapy (ART) in which human immunodeficiency virus type 1 (HIV-1) infection affected children can expect a better prognosis, the importance of careful follow up of pediatric HIV-1 cases for neurological complications has been growing. We present a case of hemorrhagic Moyamoya syndrome in a child with congenital HIV-1 infection. A 10-year-old girl was referred to our hospital for the treatment of Pneumocystis Jirovecii Pneumonia (PCP: Pneumocystis pneumonia). Her HIV-1 control was poor and Moyamoya syndrome was found during the opportunistic infection screening at admission. Despite subsequent successful treatment of PCP and HIV-1 infection, we could not save her life due to the intracranial hemorrhage caused by Moyamoya syndrome. A few reported cases of Moyamoya syndrome associated with HIV-1 infection have shown negative outcomes when the control of HIV-1 infection is unsuccessful. Recently "HIV-associated vasculopathy" has been used to describe the cerebrovascular disorder related to HIV-1 infection that is caused by the endothelial dysfunction induced from chronic inflammation and cytokine imbalances due to HIV-1 infection. We assumed that "HIV-associated vasculopathy" may have contributed to the development of collateral vessels impairment related to the bleeding, although the mechanism of vascular damage with HIV-1 infection is not yet well defined. Therefore proper management of the HIV-1 infection is crucial for Moyamoya syndrome with HIV-1 cases. Furthermore it is better to take into account the risk of intracerebral hemorrhage when considering the indication and timing of the revascularization surgery, although generally hemorrhaging is rare in Moyamoya disease in children.

Ventriculoperitoneal shunt insertion for hydrocephalus in human immunodeficiency virus-infected adults: a systematic review and meta-analysis protocol

BACKGROUND

Hydrocephalus is a recognised complication of human immunodeficiency virus (HIV)-related opportunistic infections. Symptomatic raised cerebrospinal fluid pressure can be treated with ventriculoperitoneal shunt insertion (VPS). In HIV-infected patients however, there is a concern that VPS might be associated with unacceptably high rates of mortality. We aim to systematically review and appraise published literature to determine reported outcomes and identify predictors of outcome following VPS in relevant subgroups of HIV-infected adults.

METHODS

The following electronic databases will be searched: The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (PubMed), EMBASE, CINAHL (EBSCOhost), LILACS (BIREME), Research Registry ( www.researchregistry.com ), the metaRegister of Controlled Trials (mRCT) ( www.controlled-trials.com ), ClinicalTrials.gov ( www.clinicaltrials.gov ) and OpenSIGLE database. Any randomised studies, cohort studies, case-control studies, interrupted time series or sequential case series reporting survival following VPS in HIV-infected individuals will be included. If high-quality homogenous studies exist, meta-analysis will be conducted to determine 1-, 6- and 12-month mortality with comparison made between underlying aetiologies of hydrocephalus.

DISCUSSION AND CONCLUSION

This study will generate a comprehensive review of VPS in HIV-infected patients for publication. The primary outcome of meta-analysis is 12-month survival. If only low-quality, heterogeneous studies are available, this study will demonstrate this deficiency and will be of value in justifying and aiding the design of future studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016052239.

Childhood maltreatment and HIV-associated neurocognitive disorders share similar pathophysiology: a potential sensitisation mechanism?

HIV-associated neurocognitive disorders (HAND) are increasingly prevalent despite the use of antiretroviral therapies. Previous research suggests that individual host factors play an important role in determining susceptibility to HAND. In this review, we propose that childhood trauma (CT) and HAND share several common aetiological mechanisms, namely hypothalamic-pituitary-adrenal axis dysregulation, neuroinflammation and oxidative stress. These convergent and consequent mechanisms may translate into an increased risk of developing HAND in individuals who have experienced early life stress. We provide an overview of basic and clinical research relating to these pathophysiological mechanisms and suggest that further research examine brain-derived neurotrophic factor and telomere length as common mediating factors and potential therapeutic targets for HAND and CT. Graphical abstract Both childhood trauma and HIV-associated neurocognitive disorders are associated with HPA axis dysregulation, inflammation and oxidative stress.

Nanocarriers for brain specific delivery of anti-retro viral drugs: challenges and achievements

HIV/AIDS is a global pandemic and the deleterious effects of human immunodeficiency virus in the brain cannot be overlooked. Though the current anti-retro viral therapy is able to reduce the virus load in the peripheral tissues of the body, the inability of the anti-retro viral drugs to cross the blood brain barrier, as such, limits its therapeutic effect in the brain. The development of newer, successful nanoparticulate drug delivery systems to enhance the feasibility of the anti-retro viral drugs to the brain, offers a novel strategy to treat the AIDS-related neuronal degradation. This review summarised the neuropathogenesis of neuroAIDS, the challenges and achievements made in the delivery of therapeutics across the BBB and the use of nanocarriers as a safe and effective way for delivering anti-retro viral drugs to the brain.

Common gene-network signature of different neurological disorders and their potential implications to neuroAIDS

The neurological complications of AIDS (neuroAIDS) during the infection of human immunodeficiency virus (HIV) are symptomized by non-specific, multifaceted neurological conditions and therefore, defining a specific diagnosis/treatment mechanism(s) for this neuro-complexity at the molecular level remains elusive. Using an in silico based integrated gene network analysis we discovered that HIV infection shares convergent gene networks with each of twelve neurological disorders selected in this study. Importantly, a common gene network was identified among HIV infection, Alzheimer's disease, Parkinson's disease, multiple sclerosis, and age macular degeneration. An mRNA microarray analysis in HIV-infected monocytes showed significant changes in the expression of several genes of this in silico derived common pathway which suggests the possible physiological relevance of this gene-circuit in driving neuroAIDS condition. Further, this unique gene network was compared with another in silico derived novel, convergent gene network which is shared by seven major neurological disorders (Alzheimer's disease, Parkinson's disease, Multiple Sclerosis, Age Macular Degeneration, Amyotrophic Lateral Sclerosis, Vascular Dementia, and Restless Leg Syndrome). These networks differed in their gene circuits; however, in large, they involved innate immunity signaling pathways, which suggests commonalities in the immunological basis of different neuropathogenesis. The common gene circuits reported here can provide a prospective platform to understand how gene-circuits belonging to other neuro-disorders may be convoluted during real-time neuroAIDS condition and it may elucidate the underlying-and so far unknown-genetic overlap between HIV infection and neuroAIDS risk. Also, it may lead to a new paradigm in understanding disease progression, identifying biomarkers, and developing therapies.

Combined Medication of Antiretroviral Drugs Tenofovir Disoproxil Fumarate, Emtricitabine, and Raltegravir Reduces Neural Progenitor Cell Proliferation In Vivo and In Vitro

The application of combination antiretroviral therapy has greatly reduced the death rate from AIDS. However, up to 50% of patients on combination antiretroviral therapy develop HIV-associated neurocognitive disorders (HAND), which is associated with residual neuroinflammation and oxidative injury in the brain. Neural stem cells (NSCs) and progenitors play a vital role in repairing neuronal injuries. Therefore, we hypothesize that combination antiretroviral therapy may adversely affect NSCs/progenitors, contributing to the increasing prevalence of HAND. Here, we show that combined medication of three antiretroviral drugs tenofovir disoproxil fumarate (TDF), emtricitabine (FTC), and raltegravir (RAL) affects NSC homeostasis and progenitor proliferation in the mouse dentate gyrus (DG). Our results also show that TDF/FTC/RAL treatment prohibits proliferation and induces apoptosis of cultured mouse neural progenitor cells (NPCs), resulting in a reduction in the viability of NPCs. Moreover, we find that TDF, among the three drugs used in this combination antiretroviral treatment, accounts for most of the effects on neural progenitors. Together, our results offer a mechanistic explanation for the prevalence of HAND in AIDS patients treated with combination antiretroviral therapy.

Neurological involvement in patients with acute/recent HIV-1 infection. A case-control study

Primary HIV-1 infection is a relevant period for its virological and epidemiological consequences. Most patients present a symptomatic disease that can be potentially serious, but neurological involvement during primary HIV-1 infection has been poorly studied. The aim of this study was to describe the characteristics and outcomes of primary HIV-1 infection patients presenting neurological symptoms and to compare them with primary HIV-1 infection patients without neurological involvement. Retrospective case-control study (1:3) comparing primary HIV-1 infection patients with and without neurological involvement enrolled in the Acute/Recent Hospital Clinic PHI Cohort between 1997 and 2016. Matching criteria included age (±10 years), gender, year of diagnosis (±4 years), and Fiebig stage. The conditional logit model was used for comparisons. Fourteen out of 463 patients (3.02%) enrolled in the Acute/Recent Hospital Clinic PHI Cohort between 1997 and 2016 presented neurological symptoms. 28.5% of cases presented as meningitis and 71.5% as meningoencephalitis. Cerebrospinal fluid showed non-specific findings, including pleocytosis with lymphocyte predominance and increased protein levels. All cases required hospitalisation, whereas only 19% of the controls did. No other pathogen was identified in any case, but five patients initiated empirically antimicrobial treatment for other aetiologies until diagnosis was confirmed. CD4/CD8 ratio was significantly lower (p = 0.039) and plasmatic viral load significantly higher in the case group, compared to controls (p = 0.028). Risk factors, HIV-1 tropism, subtype distribution, and prescribed ART regimens were comparable between cases and controls. After 6 months on ART, 92% of cases had undetectable viral load, similar to controls, and CD4/CD8 ratio became also comparable between groups. All cases recovered rapidly with ART and were discharged without sequels. Neurological involvement during primary HIV-1 infection is unusual but serious, always requiring hospitalisation. Diagnosis is difficult because of the wide range of symptoms and similarities with other viral aetiologies. Neurological manifestations during primary HIV-1 infection are associated with a lower CD4/CD8 ratio and with a higher viral load than controls. Immediate ART initiation and rapid viral load decrease are required, allowing complete clinical recovery.

Factors Associated with Health Information Seeking, Processing, and Use Among HIV Positive Adults in the Dominican Republic

Effective treatment and management of human immunodeficiency virus (HIV) depend on patients' ability to locate, comprehend, and apply health information. This study's purpose was to identify characteristics associated with these skills among HIV positive adults in the Dominican Republic. An information behavior survey was administered to 107 participants then three logistic regressions were conducted to identify characteristics associated with information seeking, processing, and use. Never having cared for someone who was sick was significantly associated with less information seeking, processing, and use. Males were more likely to be active information seekers and those who had attended the clinic for six or fewer years were less likely to actively seek information. Younger individuals had increased odds of higher information processing and those without comorbidities had increased odds of more information use. Results may inform researchers, organizations, and providers about how patients interact with health information in limited resource settings.

Diagnostic accuracy of SPECT, PET, and MRS for primary central nervous system lymphoma in HIV patients: A systematic review and meta-analysis

BACKGROUND

We performed a systematic review and meta-analysis to assess the roles of SPECT, PET, and MRS in distinguishing primary central nervous system lymphoma (PCNSL) from other focal brain lesions (FBLs) in human immunodeficiency virus (HIV)-infected patients.

METHODS

PubMed, Scopus, and Medline were systematically searched for eligible studies from 1980 to 2016. Two authors extracted characteristics of patients and their lesions using predefined criteria.

RESULTS

Eighteen studies on SPECT containing 667 patients, 6 studies on PET containing 108 patients, and 3 studies on MRS containing 96 patients were included. SPECT had a pooled sensitivity of 0.92 (95% CI: 0.85-0.96) and specificity of 0.84 (95% CI: 0.74-0.90) in differentiating PCNSL from other FBLs. For the 6 studies that used only pathology and/or serology as the gold standard, the pooled sensitivity was 0.85 (95% CI: 0.72-0.97) and the pooled specificity was 0.73 (95% CI: 0.54-0.92).

CONCLUSION

SPECT has good diagnostic accuracy for discriminating PCNSL from other FBL-causing disorders in HIV patients. However, the actual sensitivity and specificity of SPECT may be lower than expected if only pathology and/or serology was used as the gold standard. PET may be superior but has less supporting clinical data and is more expensive.

The viral protein gp120 decreases the acetylation of neuronal tubulin: potential mechanism of neurotoxicity

The human immunodeficiency virus (HIV) envelope protein gp120 promotes axonal damage and neurite pruning, similar to that observed in HIV-positive subjects with neurocognitive disorders. Thus, gp120 has been used to examine molecular and cellular pathways underlying HIV-mediated neuronal dysfunction. Gp120 binds to tubulin beta III, a component of neuronal microtubules. Microtubule function, which modulates the homeostasis of neurons, is regulated by polymerization and post-translational modifications. Based on these considerations, we tested the hypothesis that gp120 induces dynamic instability of neuronal microtubules. We first observed that gp120 prevents the normal polymerization of tubulin in vitro. We then tested whether gp120 alters the post-translational modifications in tubulin by examining the ability of gp120 to change the levels of acetylated tubulin in primary rat neuronal cultures. Gp120 elicited a time-dependent decrease in tubulin acetylation that was reversed by Helix-A peptide, a compound that competitively displaces the binding of gp120 to neuronal microtubules. To determine whether post-translational modifications in tubulin also occur in vivo, we measured acetylated tubulin in the cerebral cortex of HIV transgenic rats (HIV-tg). We observed a decrease in tubulin acetylation in 5- and 9-month-old HIV-tg rats when compared to age-matched wild type. Neither changes in microglia morphology nor alterations in mRNA levels for interleukin-1β and tumor necrosis factor α were detected in 5-month-old animals. Our findings propose neuronal microtubule instability as a novel mechanism of HIV neurotoxicity, without evidence of enhanced inflammation.

Productive infection of human neural progenitor cells by R5 tropic HIV-1: opiate co-exposure heightens infectivity and functional vulnerability

OBJECTIVE

HIV type-1 (HIV-1) causes a spectrum of central nervous system (CNS) complications; many are worsened by opiate co-exposure. Human neural progenitor cells (hNPCs) give rise to all CNS neurons and macroglia. We tested the hypothesis that hNPC maturation and fate are altered by HIV and opiates, contributing to HIV-1-related neuropathology. Reports of hNPC infection remain controversial. We rigorously examined this question, testing whether hNPCs propogated infection, and whether HIV affected hNPCs absent their infection.

DESIGN AND METHODS

Primary hNPCs were characterized over multiple passages. Following R5 HIV-1BaL exposure, p24, Nef, and tat assays monitored infection; a serial dilution approach tested infection transfer to naive hNPCs. Bromodeoxyuridine uptake, population doubling time, and immunostaining assessed proliferation and differentiation. Morphine co-exposure assessed opiate interactions. Supernatant from HIV-1BaL-infected PBMCs (HIVsup), HIV-1BaL, and ultraviolet light-inactivated HIVsup were compared to test effects of inflammatory milieu versus virus or infection per se.

RESULTS

The hNPCs (CD4/CD8/Iba/CXC3CL1/CD11b) were infectable and could transfer infection to naive hNPCs. Infection was partly blocked by maraviroc, implicating CCR5. HIVsup reduced hNPC proliferation and caused premature differentiation into neurons/astroglia. Effects on proliferation were due to soluble factors/viral proteins, not infection per se. Morphine co-exposure exacerbated certain functional consequences of HIVsup, and sustained the infection of hNPCs.

CONCLUSION

hNPCs can be infected and propagate virus in vitro. hNPCs or their progeny may represent an underappreciated viral reservoir. Factors from infected cells alter hNPC proliferation and neural cell maturation, which likely compromises CNS structure and function. Morphine-HIV interactions may worsen dysfunction and sustain infection.

HIV-associated neurocognitive disorders: recent advances in pathogenesis, biomarkers, and treatment

HIV-associated neurocognitive disorders (HAND) remain prevalent despite plasma viral suppression by antiretroviral agents. In fact, the prevalence of milder subtypes of cognitive impairment is increasing. Neuropsychologic testing remains the "gold standard" of diagnosis; however, this is time consuming and costly in a resource-poor environment. Recently developed screening tools, such as CogState and the revised HIV dementia scale, have very good sensitivity and specificity in the more severe stages of HAND. However, questions remain regarding the utility of, optimal population for, and insensitivity of tests in mild HAND. Recognition of ongoing viral persistence and the inflammatory milieu in the central nervous system (CNS) has advanced our understanding of the pathogenesis of HAND and facilitated the development of biomarkers of CNS disease. The importance of the monocyte-macrophage lineage cell and the astrocyte as viral reservoirs, HIV viral proteins, self-perpetuating CNS inflammation, and CCR5 chemokine receptor neurotropism has been identified. Whilst biomarkers demonstrate monocyte activation, inflammation, and neuronal injury, they remain limited in their clinical utility. The improved understanding of pathogenic mechanisms has led to novel approaches to the treatment of HAND; however, despite these advances, the optimal management is still undefined.

Prevalence of Peripheral Neuropathy and associated factors in HIV-infected patients

The progress on HIV infection treatment has allowed a longer survival for HIV-infected patients. However, chronic comorbidities are emerging. Peripheral Neuropathy (PN) represents one of the most prevalent neurologic disorders among these patients, and comprehensive studies may contribute to a reduction in the morbidity of this condition. This is a cross-sectional analytic study conducted in a tertiary referral hospital in southern Brazil. This study investigates the prevalence of PN among HIV-infected patients and associated demographic, clinical and laboratory variables. A number of 150 HIV-infected patients admitted between January and May 2016 were interviewed, submitted to physical and neurological examination, and data from their medical records were obtained. The prevalence of PN was 31.3%. It was increased among older patients (p=0.02), patients with higher CD4 lymphocytes levels (p=0.02), and smokers (OR=3.4; 95% CI 1.6-6.9; p<0.01). The research identified a high prevalence of PN in HIV-infected patients. Older age and higher CD4 levels have been associated with PN. To the best of our knowledge, this was one of the first studies reporting an association between tobacco use and PN among HIV-infected patients. Further studies are necessary to elucidate the pathological mechanisms linking PN and tobacco.

A317491 relieved HIV gp120-associated neuropathic pain involved in P2X3 receptor in dorsal root ganglia

Glycoprotein 120 (gp120) is an HIV envelope glycoprotein. Gp120 can directly stimulate the primary sensory afferent neurons and cause hyperalgesia. The P2X₃ receptor in dorsal root ganglia (DRG) is involved in the transmission of pain. In this study, we aimed to explore the role of the P2X₃ receptor in gp120-induced neuropathic pain. Our data showed that mechanical and thermal hyperalgesia in rats treated with gp120 were increased compared to those in the control group. The expression levels of the P2X₃ mRNA and protein in rats treated with gp120 were higher than those in the control group. The P2X₃ antagonist A317491 decreased mechanical hyperalgesia and thermal hyperalgesia and the up-regulated expression levels of P2X₃ mRNA and protein in rats treated with gp120. A317491 decreased ERK1/2 phosphorylation levels in the gp120-treated rat DRG. In addition, P2X₃ agonist α,β-methylene ATP (α,β-meATP)-activated currents in DRG neurons cultured with gp120 were higher than those in control neurons. The inhibitory effect of A317491 on α,βme-ATP-induced currents in DRG neurons from the gp120-treated neurons was larger than that for control neurons. Molecular docking data showed that A317491 may be acted in the gp120 protein to inhibit the gp120 initiated the P2X₃ activation, decrease the sensitizing DRG primary afferents and reduce the signal transmission of neuropathic pain in gp120-treated rats. Therefore, the inhibition of the P2X₃ receptor in rat DRG neurons relieved gp120-induced mechanical hyperalgesia.

An Overview of Human Immunodeficiency Virus Type 1-Associated Common Neurological Complications: Does Aging Pose a Challenge?

With increasing survival of patients infected with human immunodeficiency virus type 1 (HIV-1), the manifestation of heterogeneous neurological complications is also increasing alarmingly in these patients. Currently, more than 30% of about 40 million HIV-1 infected people worldwide develop central nervous system (CNS)-associated dysfunction, including dementia, sensory, and motor neuropathy. Furthermore, the highly effective antiretroviral therapy has been shown to increase the prevalence of mild cognitive functions while reducing other HIV-1-associated neurological complications. On the contrary, the presence of neurological disorder frequently affects the outcome of conventional HIV-1 therapy. Although, both the children and adults suffer from the post-HIV treatment-associated cognitive impairment, adults, especially depending on the age of disease onset, are more prone to CNS dysfunction. Thus, addressing neurological complications in an HIV-1-infected patient is a delicate balance of several factors and requires characterization of the molecular signature of associated CNS disorders involving intricate cross-talk with HIV-1-derived neurotoxins and other cellular factors. In this review, we summarize some of the current data supporting both the direct and indirect mechanisms, including neuro-inflammation and genome instability in association with aging, leading to CNS dysfunction after HIV-1 infection, and discuss the potential strategies addressing the treatment or prevention of HIV-1-mediated neurotoxicity.

Distinct Patterns of Tryptophan Maintenance in Tissues during Kynurenine Pathway Activation in Simian Immunodeficiency Virus-Infected Macaques

Induction of the kynurenine pathway (KP) of tryptophan (TRP) catabolism has been proposed to contribute to T cell dysfunction during human/simian immunodeficiency virus (SIV) infection via depletion of local TRP levels and production of immunomodulatory KP metabolites. However, while changes in TRP and KP metabolites have been observed in plasma, their levels in lymphoid tissues and levels of enzymes downstream of indoleamine 2,3-dioxygenase (IDO1) have been relatively unexplored. We used our SIV-infected pigtailed macaque model to analyze longitudinal changes in KP metabolites and enzymes by gas chromatography/mass spectrometry and NanoString nCounter gene expression analysis, respectively, in spleen and blood compared to changes previously established in brain and CSF. We found that TRP levels were remarkably stable in tissue sites despite robust depletion in the circulating plasma and CSF. We also demonstrated that intracellular TRP reserves were maintained in cultured cells even in the presence of depleted extracellular TRP levels. Kynurenine (KYN), 3-hydroxykynurenine, quinolinic acid, and the KP enzymes all displayed highly divergent patterns in the sites examined, though IDO1 expression always correlated with local KYN/TRP ratios. Finally, we demonstrated by fluorescence-activated cell sorting that myeloid dendritic cells and cells of monocytic lineage were the highest producers of IDO1 in chronically infected spleens. Overall, our study reveals insights into the tissue-specific regulation of KP enzymes and metabolites and, in particular, highlights the multiple mechanisms by which cells and tissues seek to prevent TRP starvation during inflammation.

HIV-1 Viral Protein R Activates NLRP3 Inflammasome in Microglia: implications for HIV-1 Associated Neuroinflammation

Human Immunodeficiency virus (HIV) enters the brain soon after seroconversion and induces chronic neuroinflammation by infecting and activating brain macrophages. Inflammasomes are cytosolic protein complexes that mediate caspase-1 activation and ensuing cleavage and release of IL-1β and -18 by macrophages. Our group recently showed that HIV-1 infection of human microglia induced inflammasome activation in NLRP3-dependent manner. The HIV-1 viral protein R (Vpr) is an accessory protein that is released from HIV-infected cells, although its effects on neuroinflammation are undefined. Infection of human microglia with Vpr-deficient HIV-1 resulted in reduced caspase-1 activation and IL-1β production, compared to cells infected with a Vpr-encoding HIV-1 virus. Vpr was detected at low nanomolar concentrations in cerebrospinal fluid from HIV-infected patients and in supernatants from HIV-infected primary human microglia. Exposure of human macrophages to Vpr caused caspase-1 cleavage and IL-1β release with reduced cell viability, which was dependent on NLRP3 expression. Increased NLRP3, caspase-1, and IL-1β expression was evident in HIV-1 Vpr transgenic mice compared to wild-type littermates, following systemic immune stimulation. Treatment with the caspase-1 inhibitor, VX-765, suppressed NLRP3 expression with reduced IL-1β expression and associated neuroinflammation. Neurobehavioral deficits showed improvement in Vpr transgenic animals treated with VX-765. Thus, Vpr-induced NLRP3 inflammasome activation, which contributed to neuroinflammation and was abrogated by caspase-1 inhibition. This study provides a new therapeutic perspective for HIV-associated neuropsychiatric disease.

Getting into the brain: Potential of nanotechnology in the management of NeuroAIDS

In spite of significant advances in antiretroviral (ARV) therapy, the elimination of human immunodeficiency virus (HIV) reservoirs from the periphery and the central nervous system (CNS) remains a formidable task. The incapability of ARV to go across the blood-brain barrier (BBB) after systemic administration makes the brain one of the dominant HIV reservoirs. Thus, screening, monitoring, and elimination of HIV reservoirs from the brain remain a clinically daunting and key task. The practice and investigation of nanomedicine possesses potentials for therapeutics against neuroAIDS. This review highlights the advancements in nanoscience and nanotechnology to design and develop specific size therapeutic cargo for efficient navigation across BBB so as to recognize and eradicate HIV brain reservoirs. Different navigation and drug release strategies, their biocompatibility and efficacy with related challenges and future prospects are also discussed. This review would be an excellent platform to understand nano-enable multidisciplinary research to formulate efficient nanomedicine for the management of neuroAIDS.

Increased subcortical neural activity among HIV+ individuals during a lexical retrieval task

BACKGROUND

Deficits in lexical retrieval, present in approximately 40% of HIV+ patients, are thought to reflect disruptions to frontal-striatal functions and may worsen with immunosuppression. Coupling frontal-striatal tasks such as lexical retrieval with functional neuroimaging may help delineate the pathophysiologic mechanisms underlying HIV-associated neurological dysfunction.

OBJECTIVE

We examined whether HIV infection confers brain functional changes during lexical access and retrieval. It was expected that HIV+ individuals would demonstrate greater brain activity in frontal-subcortical regions despite minimal differences between groups on neuropsychological testing. Within the HIV+ sample, we examined associations between indices of immunosuppression (recent and nadir CD4+ count) and task-related signal change in frontostriatal structures. Method16 HIV+ participants and 12 HIV- controls underwent fMRI while engaged in phonemic/letter and semantic fluency tasks. Participants also completed standardized measures of verbal fluency

RESULTS

HIV status groups performed similarly on phonemic and semantic fluency tasks prior to being scanned. fMRI results demonstrated activation differences during the phonemic fluency task as a function of HIV status, with HIV+ individuals demonstrating significantly greater activation in BG structures than HIV- individuals. There were no significant differences in frontal brain activation between HIV status groups during the phonemic fluency task, nor were there significant brain activation differences during the semantic fluency task. Within the HIV+ group, current CD4+ count, though not nadir, was positively correlated with increased activity in the inferior frontal gyrus and basal ganglia.

CONCLUSION

During phonemic fluency performance, HIV+ patients recruit subcortical structures to a greater degree than HIV- controls despite similar task performances suggesting that fMRI may be sensitive to neurocompromise before overt cognitive declines can be detected. Among HIV+ individuals, reduced activity in the frontal-subcortical structures was associated with lower CD4+ count.

Recent Progress in the Development of HIV-1 Protease Inhibitors for the Treatment of HIV/AIDS

HIV-1 protease inhibitors continue to play an important role in the treatment of HIV/AIDS, transforming this deadly ailment into a more manageable chronic infection. Over the years, intensive research has led to a variety of approved protease inhibitors for the treatment of HIV/AIDS. In this review, we outline current drug design and medicinal chemistry efforts toward the development of next-generation protease inhibitors beyond the currently approved drugs.

HIV-1 Tat and Cocaine Impair Survival of Cultured Primary Neuronal Cells via a Mitochondrial Pathway

Addictive stimulant drugs, such as cocaine, are known to increase the risk of exposure to HIV-1 infection and hence predispose towards the development of AIDS. Previous findings suggested that the combined effect of chronic cocaine administration and HIV-1 infection enhances cell death. Neuronal survival is highly dependent on the health of mitochondria providing a rationale for assessing mitochondrial integrity and functionality following cocaine treatment, either alone or in combination with the HIV-1 viral protein Tat, by monitoring ATP release and mitochondrial membrane potential (ΔΨm). Our results indicate that exposing human and rat primary hippocampal neurons to cocaine and HIV-1 Tat synergistically decreased both mitochondrial membrane potential and ATP production. Additionally, since previous studies suggested HIV-1 infection alters autophagy in the CNS, we investigated how HIV-1 Tat and cocaine affect autophagy in neurons. The results indicated that Tat induces an increase in LC3-II levels and the formation of Parkin-ring-like structures surrounding damaged mitochondria, indicating the possible involvement of the Parkin/PINK1/DJ-1 (PPD) complex in neuronal degeneration. The importance of mitochondrial damage is also indicated by reductions in mitochondrial membrane potential and ATP content induced by HIV-1 Tat and cocaine.