The Complex Interaction Between Methamphetamine Abuse and HIV-1 Pathogenesis

Efficacy of transcutaneous electrical acupoint stimulation for immunological non-responder in HIV/AIDS combined with amphetamine abuse: study protocol for a randomized controlled trial

BACKGROUND

Amphetamine-type stimulant (ATS) abuse is strongly associated with an elevated risk of HIV infection and transmission. Antiretroviral therapy (ART) serves as the primary approach for managing HIV infection and AIDS progression. However, ATS abuse diminishes the efficacy of ART in HIV/AIDS patients, amplifying the vulnerability to immunological non-response (INR) and ultimately increasing the incidence rate and mortality of opportunistic infections. Currently, no effective interventions targeting INR exist. Acupuncture has demonstrated promise in bidirectionally modulating the body's immune response and may be beneficial for INR in HIV/AIDS combined with ATS abuse. Nevertheless, further research and comprehensive evaluation are imperative to substantiate these findings.

METHODS

This study is a two-center, randomized, non-acupoint controlled, single-blind clinical trial. It will be conducted in two large drug rehabilitation centers in western China, involving 114 INR patients receiving ART. The participants will be randomly assigned to either the Transcutaneous Electrical Acupoint Stimulation (TEAS) + ART group or the sham-TEAS + ART group, in a 1:1 ratio. Both groups will receive a 48-week treatment. The primary outcome measure assessed after treatment is the CD4 + T cell count. Secondary outcome measures include the immune reconstitution efficiency of HIV patients, CD4/CD8 ratio, CD4 + CD45RA + and CD4 + CD45RO + counts, CD4 + CD28 + counts, CD4 + CD38 + and CD8 + CD38 + counts, CD4 + ki67 + and CD8 + ki67 + counts, JC mitochondrial membrane potential testing, the incidence of opportunistic infections, and the HIV/AIDS PRO scale. Adverse events occurring during the study observation period will be documented.

DISCUSSION

This study will investigate the effect of TEAS on immune reconstitution in patients with amphetamine abuse and HIV infection.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR 2300076363. Registered on October 7, 2023, https://www.chictr.org.cn/ .

Antiretroviral Treatment Adherence among People Living with HIV in Taipei, Taiwan

INTRODUCTION

Adherence to Highly Active Antiretroviral Therapy (HAART) is critical in controlling HIV. Poor medication adherence may lead to higher disease mortality, increased HIV spread, and transmission of drug-resistant strains. Identifying the specific factors that contribute to suboptimal medication adherence in people with HIV is crucial for developing effective, personalized interventions.

METHODS

This study conducted a cross-sectional analysis by enrolling individuals over 18 years of age with HIV at a single clinic in Taipei, Taiwan, from December 2018 to November 2020. Participants completed a questionnaire that collected demographic data, recreational drug use, comorbidities, and history of sexually transmitted infections (STIs). The Medication Adherence Report Scale (MARS-5) was utilized to assess treatment adherence. A multiple logistic regression model was applied to identify the factors influencing adherence.

RESULTS

A total of 831 PWH were included in the analysis. After controlling for demographics, comorbidities, and recreational drug use, independent risk factors associated with poor adherence among PWH include the presence of a depressive disorder (AOR:2·887, 95% CI:1·461-5·703, p = 0·002), a history of acquired gonorrhea (AOR:2·026, 95% CI:1·079 - 3·803, p = 0·028), methamphetamine use within past three months (AOR:2·073, 95% CI:1·172-3·665, p = 0·012), HIV-1 RNA ≥ 40 copies/ml (AOR:5·221, 95% CI:2·976-9·157, p < 0·001) and younger age (AOR:0·959, 95% CI:0·932-0·988, p = 0·006).

CONCLUSIONS

To enhance HIV treatment adherence, targeted efforts are essential for PWH who are young, have used methamphetamine in the past three months, are experiencing depressive disorders, or have previously acquired gonorrhea.

Matrix Metalloproteinase-9 Signaling Regulates Colon Barrier Integrity in Models of HIV Infection

Infection with human immunodeficiency virus (HIV) increases risk for maladies of the gut barrier, which promotes sustained systemic inflammation even in virally controlled patients. We previously revealed morphological disorganization of colon epithelial barrier proteins in HIV-1 transgenic (Tg) rats. The current study evaluated mechanisms that may underlie gut barrier pathology induced by toxic HIV-1 proteins. Methamphetamine (meth) use is prevalent among HIV-infected individuals, and meth can exaggerate morbidity of HIV infection. Thus, we determined whether meth exposure worsened HIV-associated gut pathology using colon samples from HIV-1 Tg and non-Tg rats that self-administered meth 2 h/day for 21 days. Immunoblotting was conducted for occludin (a gut barrier protein) and matrix metalloproteinase-9 (MMP-9; a proteinase regulator of occludin). Colon levels of occludin were decreased, and MMP-9 levels and activity were increased in HIV-1 Tg rats. A Pearson correlation revealed an inverse relationship between occludin levels and MMP-9 activity. Doses of meth that were self-administered by Tg rats were lower than other rat models. Meth-induced trends in non-Tg rats were not significant, and meth did not exaggerate effects seen in Tg rats. Accordingly, only the HIV-effects on epithelial function were explored further. Transepithelial resistance (TER) across a monolayer of human colon epithelial cells (Caco-2) was used to examine treatments with the HIV-1 toxic protein, Tat, and the ability of pioglitazone, a PPARγ agonist that inhibits MMP-9, to mitigate Tat-induced changes. Exposure to Tat for 24 h decreased TER, which co-occurred with decreases in levels of barrier tight junction proteins (occludin, claudin-1, and zonula occludens-1) and with increases in the level and activity of MMP-9. Pretreatment or post-treatment with pioglitazone respectively prevented and restored Tat-induced impairments of Caco-2 barrier. Thus, while low doses of meth did not alter barrier proteins in the current study, exposure to HIV-1 proteins disrupted the gut barrier, and this action involved a dysregulation of MMP-9.

Structural Determinants of Health and Markers of Immune Activation and Systemic Inflammation in Sexual Minority Men With and Without HIV

Among sexual minority men (SMM), HIV and use of stimulants such as methamphetamine are linked with immune activation and systemic inflammation. Throughout the COVID-19 pandemic, SMM encountered financial challenges and structural obstacles that might have uniquely contributed to immune dysregulation and systemic inflammation, beyond the impacts of HIV and stimulant use. Between August 2020 and February 2022, 72 SMM with and without HIV residing in South Florida enrolled in a COVID-19 prospective cohort study. Multiple linear regression analyses examined unemployment, homelessness, and history of arrest as structural correlates of soluble markers of immune activation (i.e., sCD14 and sCD163) and inflammation (i.e., sTNF-α receptors I and II) at baseline after adjusting for HIV status, stimulant use, and recent SARS-CoV-2 infection. Enrolled participants were predominantly Latino (59%), gay-identified (85%), and with a mean age of 38 (SD, 12) years with approximately one-third (38%) of participants living with HIV. After adjusting for HIV status, SARS-CoV-2 infection, and recent stimulant use, unemployment independently predicted higher levels of sCD163 (β = 0.24, p = 0.04) and sTNF-α receptor I (β = 0.26, p = 0.02). Homelessness (β = 0.25, p = 0.02) and history of arrest (β = 0.24, p = 0.04) independently predicted higher levels of sCD14 after adjusting for HIV status, SARS-CoV-2 infection, and recent stimulant use. Independent associations exist between structural barriers and immune activation and systemic inflammation in SMM with and without HIV. Future longitudinal research should further elucidate complex bio-behavioral mechanisms linking structural factors with immune activation and inflammation.

The Impact of Drugs and Substance Abuse on Viral Pathogenesis-A South African Perspective

Illicit drug and alcohol abuse have significant negative consequences for individuals who inject drugs/use drugs (PWID/UDs), including decreased immune system function and increased viral pathogenesis. PWID/UDs are at high risk of contracting or transmitting viral illnesses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). In South Africa, a dangerous drug-taking method known as "Bluetoothing" has emerged among nyaope users, whereby the users of this drug, after injecting, withdraw blood from their veins and then reinject it into another user. Hence, the transmission of blood-borne viruses (BBVs) is exacerbated by this "Bluetooth" practice among nyaope users. Moreover, several substances of abuse promote HIV, HBV, and HCV replication. With a specific focus on the nyaope drug, viral replication, and transmission, we address the important influence of abused addictive substances and polysubstance use in this review.

HIV-1 and methamphetamine co-treatment in primary human astrocytes: TAARgeting ER/UPR dysfunction

Objectives

Human immunodeficiency virus 1 (HIV-1) can invade the central nervous system (CNS) early during infection and persist in the CNS for life despite effective antiretroviral treatment. Infection and activation of residential glial cells lead to low viral replication and chronic inflammation, which damage neurons contributing to a spectrum of HIV-associated neurocognitive disorders (HAND). Substance use, including methamphetamine (METH), can increase one's risk and severity of HAND. Here, we investigate HIV-1/METH co-treatment in a key neurosupportive glial cell, astrocytes. Specifically, mitochondria-associated endoplasmic reticulum (ER) membrane (MAM) signaling pathways, such as calcium and the unfolded protein response (UPR), are key mechanisms underlying HAND pathology and arise as potential targets to combat astrocyte dysfunction.

Methods

Primary human astrocytes were transduced with a pseudotyped HIV-1 model and exposed to low-dose METH for seven days. We assessed changes in astrocyte HIV-1 infection, inflammation, mitochondrial antioxidant and dynamic protein expression, respiratory acitivity, mitochondrial calcium flux, and UPR/MAM mediator expression. We then tested a selective antagonist for METH-binding receptor, trace amine-associated receptor 1 (TAAR1) as a potetnial upstream regulator of METH-induced calcium flux and UPR/MAM mediator expression.

Results

Chronic METH exposure increased astrocyte HIV-1 infection. Moreover, HIV-1/METH co-treatment suppressed astrocyte antioxidant and metabolic capacity while increasing mitochondrial calcium load and protein expression of UPR messengers and MAM mediators. Notably, HIV-1 increases astrocyte TAAR1 expression, thus, could be a critical regulator of HIV-1/METH co-treatment in astrocytes. Indeed, selective antagonism of TAAR1 significantly inhibited cytosolic calcium flux and induction of UPR/MAM protein expression.

Conclusion

Altogether, our findings demonstrate HIV-1/METH-induced ER-mitochondrial dysfunction in astrocytes, whereas TAAR1 may be an upstream regulator for HIV-1/METH-mediated astrocyte dysfunction.

Association of current substance use treatment with future reduced methamphetamine use in an observational cohort of men who have sex with men in Los Angeles

INTRODUCTION

Methamphetamine use is highly prevalent among men who have sex with men (MSM), but knowledge of the long-term dynamics, and how they are affected by substance use treatment, is limited. This study aimed to describe trajectories of methamphetamine use among MSM, and to evaluate the impact of treatment for any kind of substance use on frequency of methamphetamine use.

METHODS

This analysis used data from a cohort of MSM in Los Angeles, CA, who participated in semi-annual study visits from 2014 to 2022. The study characterized trajectories of methamphetamine use using a continuous time multistate Markov model with three states. States were defined using self-reported frequency of methamphetamine use in the past six months: frequent (daily), occasional (weekly or less), and never. The model estimated the association between receiving treatment for any kind of substance use and changes in state of frequency of methamphetamine use.

RESULTS

This analysis included 2348 study visits among 285 individuals who were followed-up for an average of 4.4 years. Among participants who were in the frequent use state, 65 % (n = 26) of those who were receiving any kind of substance use treatment at a study visit had reduced their methamphetamine use at their next visit, compared to 33 % (n = 95) of those who were not receiving treatment. Controlling for age, race/ethnicity, and HIV-status, those who reported receiving current treatment for substance use were more likely to transition from occasional to no use (HR: 1.63, 95 % CI: 1.10-2.42) and frequent to occasional use (HR: 4.25, 95 % CI: 2.11-8.59) in comparison to those who did not report receiving current treatment for substance use.

CONCLUSIONS

Findings from this dynamic modeling study provide a new method for assessing longitudinal methamphetamine use outcomes and add important evidence outside of clinical trials that substance use treatment may reduce methamphetamine use.

Development and internal validation of a risk prediction model for HIV disease severity among people living with HIV and mental illness or substance use disorder

PURPOSE

Mental illness (MI) and substance use disorders (SUD) are highly prevalent among people living with HIV (PLWH), and have been linked to poor HIV clinical outcomes. Innovative tools for early risk identification can facilitate timely interventions for PLWH and MI/SUD to improve their health outcomes, however, this is currently lacking in Texas, a state with the 4th largest population of PLWH in the United States. To address this gap, we developed a predictive model to estimate the risk of suboptimal HIV clinical outcomes among PLWH and MI/SUD in Texas.

METHODS

The Texas Medical Monitoring Project data obtained from June 2015-May 2020 were used to develop and internally validate the predictive model. Univariate descriptive and bivariate inferential statistics were performed to describe the characteristics of the study population and unadjusted associations with HIV clinical outcomes. Multivariable logistic regression was used to develop the prediction model. Internal validation was performed using the bootstrap method.

RESULTS

A total of 518 respondents aged 18 years and above, representing 27,255 adults living with HIV and mental illness or substance use disorders in Texas were included. Most participants were male (77.0%), less than 50 years of age (60.0%), and had mild diagnosed mental illness and substance use disorder (54.8%). The risk predictive model contained eight predictors, which together yielded an area under the receiver operating characteristic (ROC) curve of 0.727. Non-retention in care appeared to be the strongest risk predictor for having suboptimal HIV clinical outcome (adjusted odds ratio (aOR) = 3.27; 95% confidence interval (CI) = 1.45, 7.42).

CONCLUSIONS

The predictive model had good discrimination between persons at risk of poor HIV clinical outcomes and those not at risk.

Change of histone H3 lysine 14 acetylation stoichiometry in human monocyte derived macrophages as determined by MS-based absolute targeted quantitative proteomic approach: HIV infection and methamphetamine exposure

BACKGROUND

Histones posttranslational modification represent an epigenetic mechanism that regulate gene expression and other cellular processes. Quantitative mass spectrometry used for the absolute quantification of such modifications provides further insight into cellular responses to extracellular insults such as infections or toxins. Methamphetamine (Meth), a drug of abuse, is affecting the overall function of the immune system. In this report, we developed, validated and applied a targeted, MS-based quantification assay to measure changes in histone H3 lysine 14 acetylation (H3K14Ac) during exposure of human primary macrophages to HIV-1 infection and/or Meth.

METHODS

The quantification assay was developed and validated to determine H3K14Ac stoichiometry in histones that were isolated from the nuclei of control (CIC) and exposed to Meth before (CIM) or/and after (MIM) HIV-infection human monocyte-derived macrophages (hMDM) of six donors. It was based on LC-MS/MS measurement using multiple reaction monitoring (MRM) acquisition of the unmodified and acetylated form of lysine K14 of histone H3 9KSTGGKAPR17 peptides and the corresponding stable isotope labeled (SIL) heavy peptide standards of the same sequences. The histone samples were propionylated (Poy) pre- and post- trypsin digestion so that the sequences of the monitored peptides were: K[Poy]STGGK[1Ac]APR, K[Poy]STGGK[1Ac]APR-heavy, K[Poy]STGGK[Poy]APR and K[Poy]STGGK[Poy]APR-heavy. The absolute amounts of the acetylated and unmodified peptides were determined by comparing to the abundances of their SIL standards, that were added to the samples in the known concentrations, and, then used for calculation of H3K14Ac stoichiometry in CIC, CIM and MIM hMDM.

RESULTS

The assay was characterized by LLOD of 0.106 fmol/µL and 0.204 fmol/µL for unmodified and acetylated H3 9KSTGGKAPR17 peptides, respectively. The LLOQ was 0.5 fmol/µL and the linear range of the assay was from 0.5 to 2500 fmol/µL. The absolute abundances of the quantified peptides varied between the donors and conditions, and so did the H3K14Ac stoichiometry. This was rather attributed to the samples nature itself, as the variability of their triplicate measurements was low.

CONCLUSIONS

The developed LC-MS/MS assay enabled absolute quantification of H3K14Ac in exposed to Meth HIV-infected hMDM. It can be further applied determination of this PTM stoichiometry in other studies on human primary macrophages.

Racial, gender, and psychosocial disparities in viral suppression trends among people receiving coordinated HIV care in Los Angeles County

OBJECTIVE

To longitudinally evaluate differences in HIV viral suppression (<200 copies/ml) by intersections of race/ethnicity, gender, and psychosocial issues in people with HIV in the Los Angeles County Medical Care Coordination Program.

DESIGN

We analyzed 74 649 viral load measurements over 10 184 people with HIV enrolled in the Medical Care Coordination Program between January 1, 2013 and March 1, 2020.Methods: We fit Bayesian logistic hierarchical random effects models to test interactions between gender, race/ethnicity, and a psychosocial acuity score on viral suppression over time from 1 year prior to program enrollment to 24 months after enrollment.

RESULTS

The probability of viral suppression declined prior to enrollment, then increased and stabilized by 6 months after enrollment. Black/African American patients with low and moderate psychosocial acuity scores did not achieve the same increase in percentage of viral suppression as those in other racial/ethnic groups. Transgender women with high psychosocial acuity scores took longer (about 1 year) to achieve the same percentage of viral suppression as clients of other gender identities.

CONCLUSIONS

Some racial/ethnic and gender disparities in viral suppression persisted after enrollment in the Los Angeles County Medical Care Coordination Program while accounting for psychosocial acuity score, which may be explained by factors not assessed in the program.

HIV and Drug Use: A Tale of Synergy in Pulmonary Vascular Disease Development

Over the past two decades, with the advent and adoption of highly active anti-retroviral therapy, HIV-1 infection, a once fatal and acute illness, has transformed into a chronic disease with people living with HIV (PWH) experiencing increased rates of cardio-pulmonary vascular diseases including life-threatening pulmonary hypertension. Moreover, the chronic consequences of tobacco, alcohol, and drug use are increasingly seen in older PWH. Drug use, specifically, can have pathologic effects on the cardiovascular health of these individuals. The "double hit" of drug use and HIV may increase the risk of HIV-associated pulmonary arterial hypertension (HIV-PAH) and potentiate right heart failure in this population. This article explores the epidemiology and pathophysiology of PAH associated with HIV and recreational drug use and describes the proposed mechanisms by which HIV and drug use, together, can cause pulmonary vascular remodeling and cardiopulmonary hemodynamic compromise. In addition to detailing the proposed cellular and signaling pathways involved in the development of PAH, this article proposes areas ripe for future research, including the influence of gut dysbiosis and cellular senescence on the pathobiology of HIV-PAH. © 2023 American Physiological Society. Compr Physiol 13:4659-4683, 2023.

Clinical management of psychostimulant withdrawal: review of the evidence

It is estimated that a majority of people who use psychostimulants, particularly methamphetamine (MA) and cocaine, experience withdrawal upon abstinence from sustained use. This review of clinical research reports the evidence regarding biomedical and behavioral treatments for psychostimulant withdrawal symptoms. It provides a framework for clinicians and scientists to increase impact on attenuating MA and cocaine withdrawal during initial and sustained abstinence. Articles reviewed included reports of controlled clinical trials (randomized or non-randomized) reporting at least one withdrawal symptom among the outcomes or specifically studying patients in withdrawal. Potential efficacy for MA withdrawal is noted for a few medications (mirtazapine, naltrexone, bupropion) and repetitive transcranial magnetic stimulation during acute (first week), early protracted (weeks 2-4) and late protracted (> 4 weeks) withdrawal phases. Topiramate shows mixed evidence of efficacy for cocaine withdrawal. In general, there is inconsistent signal for biomedical and behavioral treatments on MA and cocaine withdrawal.

Vision health perspectives on Breaking Bad: Ophthalmic sequelae of methamphetamine use disorder

Methamphetamine use has become a rampant public health issue that not only causes devastating consequences to the user but also poses a burden to surrounding communities. A spectrum of ophthalmic sequelae is associated with methamphetamine use and includes episcleritis, scleritis, corneal ulceration, panophthalmitis, endophthalmitis, retinal vasculitis, and retinopathy. In many instances, prompt recognition of the condition and associated infectious process and early initiation of antimicrobial therapy are crucial steps to preventing vision loss. In this review, we summarize the reported ocular complications that may result from methamphetamine use in addition to several postulated mechanisms regarding the ocular toxicity of methamphetamine. The increasing prevalence of methamphetamine use as a public health threat highlights the need for continued investigation of this ophthalmologic issue.

Social Genomics of Methamphetamine Use, HIV Viral Load, and Social Adversity

Background

Social genomics has demonstrated altered inflammatory and type I interferon (IFN) gene expression among people experiencing chronic social adversity. Adverse social experiences such as discrimination and violence are linked to stimulant misuse and HIV, conditions that dysregulate inflammatory and innate antiviral responses, leading to increased HIV viral replication and risk of chronic diseases.

Purpose

We aimed to determine whether methamphetamine (MA) use, unsuppressed HIV viral load (VL) (≥200 c/mL), and experienced intimate partner violence (IPV) (past 12 months) predicted inflammatory and type I IFN gene expression in HIV-positive Black and Latinx men who have sex with men (MSM).

Methods

Participants were 147 HIV-positive Black and Latinx MSM recruited from the mSTUDY, a cohort of 561 MSM aged 18–45 in Los Angeles, CA, of whom half are HIV-positive and substance-using. Transcriptomic measures of inflammatory and type I IFN activity were derived from RNA sequencing of peripheral blood mononuclear cells and matched to urine drug tests, VL, and survey data across two time points 12 months apart. Analysis used linear random intercept modeling of MA use, unsuppressed VL, and experienced IPV on inflammatory and type I IFN expression.

Results

In adjusted models, MA use predicted 27% upregulated inflammatory and 31% upregulated type I IFN expression; unsuppressed VL predicted 84% upregulated type I IFN but not inflammatory expression; and experienced IPV predicted 31% upregulated inflammatory and 26% upregulated type I IFN expression.

Conclusions

In Black and Latinx MSM with HIV, MA use, unsuppressed VL, and experienced IPV predicted upregulated social genomic markers of immune functioning.

HIV-related drivers of sexual compulsivity and sexuality in sexual minority men who use methamphetamine

Although co-occurring methamphetamine (meth) use and HIV amplify the risk for neuropsychiatric comorbidities, the underlying neuroimmune mechanisms are not well characterized. We examined whether a detectable viral load and dysregulated metabolism of amino acid precursors for neurotransmitters predicted subsequent levels of sexual compulsivity and sexual sensation seeking. This 15-month longitudinal study enrolled 110 sexual minority men (SMM) living with HIV who had biologically confirmed meth use (i.e., reactive urine or hair toxicology results). Peripheral venous blood samples collected at baseline, 6 months, 12 months, and 15 months were used to measure a detectable viral load (> 40 copies/mL), the kynurenine/tryptophan (K/T) ratio, and the phenylalanine/tyrosine (P/T) ratio. The K/T and P/T ratios index dysregulated serotonin and catecholamine (e.g., dopamine) synthesis, respectively. In a cross-lagged panel model, a detectable viral load at 6 months predicted greater sexual compulsivity at 12 months after adjusting for prior levels of sexual compulsivity and recent stimulant use (β = 0.26, p = 0.046). A greater P/T ratio at baseline predicted decreased sexual sensation seeking at 6 months (β = - 0.25, p = 0.004) after adjusting for baseline sexual sensation seeking and recent stimulant use. Taken together, HIV replication and dysregulated catecholamine synthesis could potentiate sexual compulsivity while decreasing sexual pleasure in SMM who use meth.

A Non-Canonical Role for IRE1α Links ER and Mitochondria as Key Regulators of Astrocyte Dysfunction: Implications in Methamphetamine use and HIV-Associated Neurocognitive Disorders

Astrocytes are one of the most numerous glial cells in the central nervous system (CNS) and provide essential support to neurons to ensure CNS health and function. During a neuropathological challenge, such as during human immunodeficiency virus (HIV)-1 infection or (METH)amphetamine exposure, astrocytes shift their neuroprotective functions and can become neurotoxic. Identifying cellular and molecular mechanisms underlying astrocyte dysfunction are of heightened importance to optimize the coupling between astrocytes and neurons and ensure neuronal fitness against CNS pathology, including HIV-1-associated neurocognitive disorders (HAND) and METH use disorder. Mitochondria are essential organelles for regulating metabolic, antioxidant, and inflammatory profiles. Moreover, endoplasmic reticulum (ER)-associated signaling pathways, such as calcium and the unfolded protein response (UPR), are important messengers for cellular fate and function, including inflammation and mitochondrial homeostasis. Increasing evidence supports that the three arms of the UPR are involved in the direct contact and communication between ER and mitochondria through mitochondria-associated ER membranes (MAMs). The current study investigated the effects of HIV-1 infection and chronic METH exposure on astrocyte ER and mitochondrial homeostasis and then examined the three UPR messengers as potential regulators of astrocyte mitochondrial dysfunction. Using primary human astrocytes infected with pseudotyped HIV-1 or exposed to low doses of METH for 7 days, astrocytes had increased mitochondrial oxygen consumption rate (OCR), cytosolic calcium flux and protein expression of UPR mediators. Notably, inositol-requiring protein 1α (IRE1α) was most prominently upregulated following both HIV-1 infection and chronic METH exposure. Moreover, pharmacological inhibition of the three UPR arms highlighted IRE1α as a key regulator of astrocyte metabolic function. To further explore the regulatory role of astrocyte IRE1α, astrocytes were transfected with an IRE1α overexpression vector followed by activation with the proinflammatory cytokine interleukin 1β. Overall, our findings confirm IRE1α modulates astrocyte mitochondrial respiration, glycolytic function, morphological activation, inflammation, and glutamate uptake, highlighting a novel potential target for regulating astrocyte dysfunction. Finally, these findings suggest both canonical and non-canonical UPR mechanisms of astrocyte IRE1α. Thus, additional studies are needed to determine how to best balance astrocyte IRE1α functions to both promote astrocyte neuroprotective properties while preventing neurotoxic properties during CNS pathologies.

Differentially Expressed Genes in Period 2-Overexpressing Mice Striatum May Underlie Their Lower Sensitivity to Methamphetamine Addiction-Like Behavior

Previous reports have demonstrated that genetic mechanisms greatly mediate responses to drugs of abuse, including methamphetamine (METH). The circadian gene Period 2 (Per2) has been previously associated with differential responses towards METH in mice. While the behavioral consequences of eliminating Per2 have been illustrated previously, Per2 overexpression has not yet been comprehensively described; although, Per2-overexpressing (Per2 OE) mice previously showed reduced sensitivity towards METH-induced addiction-like behaviors. To further elucidate this distinct behavior of Per2 OE mice to METH, we identified possible candidate biomarkers by determining striatal differentially expressed genes (DEGs) in both drug-naïve and METH-treated Per2 OE mice relative to wild-type (WT), through RNA sequencing. Of the several DEGs in drug naïve Per2 OE mice, we identified six genes that were altered after repeated METH treatment in WT mice, but not in Per2 OE mice. These results, validated by quantitative real-time polymerase chain reaction, could suggest that the identified DEGs might underlie the previously reported weaker METH-induced responses of Per2 OE mice compared to WT. Gene network analysis also revealed that Asic3, Hba-a1, and Rnf17 are possibly associated with Per2 through physical interactions and predicted correlations, and might potentially participate in addiction. Inhibiting the functional protein of Asic3 prior to METH administration resulted in the partial reduction of METH-induced conditioned place preference in WT mice, supporting a possible involvement of Asic3 in METH-induced reward. Although encouraging further investigations, our findings suggest that these DEGs, including Asic3, may play significant roles in the lower sensitivity of Per2 OE mice to METH.

HIV-1 and methamphetamine alter galectins -1, -3, and -9 in human monocyte-derived macrophages

Macrophages are key elements of the innate immune system. Their HIV-1 infection is a complex process that involves multiple interacting factors and various steps and is further altered by exposure of infected cells to methamphetamine (Meth), a common drug of abuse in people living with HIV. This is reflected by dynamic changes in the intracellular and secreted proteomes of these cells. Quantification of these changes poses a challenge for experimental design and associated analytics. In this study, we measured the effect of Meth on expression of intracellular and secreted galectins-1, -3, and -9 in HIV-1 infected human monocyte-derived macrophages (hMDM) using SWATH-MS, which was further followed by MRM targeted mass spectrometry validation. Cells were exposed to Meth either prior to or after infection. Our results are the first to perform comprehensive quantifications of galectins in primary hMDM cells during HIV-1 infection and Meth exposure a building foundation for future studies on the molecular mechanisms underlying cellular pathology of hMDM resulting from viral infection and a drug of abuse—Meth.

Social Networks and Exchange Sex among Transgender Women

Transgender women are more likely to exchange sex than cisgender individuals. This study investigated how social networks were associated with exchange sex among transgender women in Los Angeles County. From July 2015 to September 2016, transgender women (N = 271; "egos") reported their sexual and substance use behaviors and perceptions of the same behaviors among their peers (N = 2,619; "alters"). Clustered logistic and negative binomial regressions were used to model odds of exchange sex and number of exchange sex partners in the past 6 months, respectively. Transgender women who perceived that any of their peers were engaged in exchange sex were approximately four times more likely to exchange sex themselves and reported three times as many exchange sex partners as those who did not perceive any peers engaged in exchange sex. Perceived ecstasy use among peers was associated with higher odds of exchange sex and more exchange sex partners, whereas perceived marijuana use among peers was associated with lower odds of exchange sex and fewer exchange sex partners. Peer behaviors were strongly associated with both transgender women's likelihood and rate of engagement in exchange sex. Risk reduction interventions with transgender women should attend to network dynamics that are often overlooked in existing programs.

Apathy is associated with poorer abstinence self-efficacy in individuals with methamphetamine dependence

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Used an apathy composite T-score approach validated in methamphetamine-dependence.

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Apathy, above other factors, associated with poorer drug abstinence self-efficacy.

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Methamphetamine use characteristics unrelated to drug abstinence self-efficacy.

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Social peer pressure was riskiest situation for potential methamphetamine relapse.

Background

Confidence in one’s ability to achieve and maintain drug abstinence (i.e., abstinence self-efficacy) is a strong predictor of substance use treatment outcomes. Neurobehavioral factors that may interfere with abstinence self-efficacy are less well established, particularly in methamphetamine (METH). This study investigated whether apathy, which is highly prevalent during active METH use and periods of abstinence, influences abstinence self-efficacy among METH dependent individuals.

Methods

Sixty-six participants with lifetime METH dependence and METH abuse/METH dependence diagnoses within the last 18 months (mean age [SD] = 39.5 years [10.7]), and no severe psychiatric or neurological diseases, completed the Methamphetamine Self-Efficacy Scale (MSES), alongside a comprehensive neurobehavioral evaluation. The MSES presents six situations that may lead to relapse and collects self-report ratings for two subscales: “Confidence” (i.e., confidence in one’s ability to abstain from using METH, or METH abstinence self-efficacy) and “Temptation” (i.e., how tempted one is to use METH) with regard to each situation. Apathy was measured using a composite T-score comprised of items and scales from three well-validated, self-report assessments.

Results

Multivariable linear regression found that higher Apathy T-scores were significantly associated with lower Confidence ratings (i.e., poorer METH abstinence self-efficacy; p < .05), independent of potentially relevant factors (e.g., Temptation to use METH, comorbid HIV disease, and neurocognitive impairment).

Conclusions

Elevated apathy may adversely impact one’s confidence to abstain from METH use. Findings highlight the importance of addressing apathy in order to improve METH abstinence self-efficacy, which may subsequently increase the likelihood of successful METH treatment outcomes.

Review of sexualized drug use associated with sexually transmitted and blood-borne infections in gay, bisexual and other men who have sex with men

PURPOSE

The aim of the present study was to quantify associations between sexualized drug use (SDU) and sexually-transmitted and blood-borne infection (STBBI) diagnoses in gay, bisexual and other men who have sex with men (GBMSM) with defined temporal proximity between SDU exposure and STBBI diagnoses.

METHODS

In May 2018 and June 2019, we searched the literature for primary studies that quantified the association between STBBI and SDU among GBMSM. A random-effects model was used to meta-analyze the data and estimate the association between SDU and STBBIs.

RESULTS

Nineteen studies met the inclusion criteria and fourteen studies were included in the meta-analyses. SDU was associated with higher odds of bacterial STI diagnoses, higher odds of HCV diagnoses, and higher odds of HIV diagnoses. Associations between SDU and diagnoses of bacterial STIs or HCV remained after adjustment for behavioral and sociodemographic factors.

CONCLUSIONS

Robust and consistent associations between SDU and STBBI identified in this review add to the evidence suggesting SDU is a potential contributor to bacterial STIs and HCV or a proxy indicator for other risk factors.

Lifetime Methamphetamine Use Disorder and Reported Sleep Quality in Adults Living with HIV

This study evaluated whether a history of lifetime methamphetamine (MA) use disorder increases risk for poor sleep quality in people with or without HIV infection (HIV+/HIV-). Participants (n = 313) were stratified into four groups based on HIV status and lifetime MA use disorder diagnosis [HIV+/MA+ (n = 84); HIV+/MA- (n = 141); HIV-/MA+ (n = 16); and HIV-/MA- (n = 72)] and compared on global sleep outcomes using the Pittsburgh Sleep Quality Index (PSQI). Significant differences on global sleep were observed between HIV+/MA+ and HIV+/MA- groups, but not between the HIV- groups. Follow-up multiple regression analyses within the HIV+ subgroups examined global sleep scores as a function of MA status and clinical covariates, including those related to HIV disease and demographics. HIV+ individuals with a history of MA use disorder evidenced significantly poorer sleep quality and were more likely to be classified as problematic sleepers than those without a lifetime disorder. This was independent of depressed mood, body mass index, and viral suppression while on treatment. Poorer reported sleep quality among HIV+/MA+ was associated also with multiple adverse functional outcomes, including greater objective cognitive impairment, unemployment, clinical ratings of functional impairment, and self-reported cognitive difficulties, decreased independence in activities of daily living, and poorer overall life quality. Interventions to avoid or curtail MA use in HIV+ individuals may help protect sleep quality and improve functioning.

The Effect of Physical Activity on Drug Cravings of Drug Addicts With AIDS: The Dual Mediating Effect of Internal Inhibition

Background

As a global infectious disease, Acquired Immune Deficiency Syndrome (AIDS) poses a serious threat to the safety and health of the society. In recent years, the proportion of drug addicts infected with HIV has been increased, and drug addicts became one of the main carriers of the spread of AIDS, which has attracted worldwide attention. It has been reported that physical activity has positive effects on improving the inhibitory function of drug addicts and reducing their drug craving, but the mechanism of the internal inhibition remains to be further explored.

Method

The drug addicts in an AIDS treatment center in Chongqing were investigated by means of a Physical Activity Rating Scale (PARS – 3), Internal Inhibition Scale and Drug Craving Scale, and a structural equation model was established.

Results

(1) There is no gender difference in the internal inhibition and drug craving of drug addicts with AIDS, and there are significant differences across the types and years of drug abuse. (2) The amount of physical activity in drug addicts with AIDS is positively correlated with the intrinsic inhibition, while the internal inhibition is negatively correlated with the drug craving, and the physical exercise amount is negatively correlated with the drug craving. The years of drug abuse were negatively correlated with internal inhibition and positively correlated with drug craving. (3) Internal inhibition plays a partly mediatory role between the physical activity amount and the craving for drugs, and internal inhibition plays a partly mediatory role between the number of years of drug abuse and the craving for drugs, which indicates that internal inhibition has a dual mediating effect.

Conclusion

Actively participate in physical activity, especially high-intensity physical activity, can effectively enhance the internal inhibition of drug addicts with AIDS and reduce their drug craving. Meanwhile, the difference in the drug-taking years among addicts should be paid attention to, and the physical activity prescription should be formulated according to the actual situation.

Sustained attention and vigilance deficits associated with HIV and a history of methamphetamine dependence

BACKGROUND

Human immunodeficiency virus (HIV)-associated neurocognitive disorders persist in the era of antiretroviral therapy. One factor that is elevated among persons with HIV (PWH) and independently associated with neurocognitive impairment is methamphetamine dependence (METH). Such dependence may further increase cognitive impairment among PWH, by delaying HIV diagnosis (and thus, antiretroviral therapy initiation), which has been posited to account for persistent cognitive impairment among PWH, despite subsequent treatment-related viral load suppression (VLS; <50 copies of the virus per milliliter in plasma or cerebrospinal fluid). This study examined the main and interactive (additive versus synergistic) effects of HIV and history of METH on the sustained attention and vigilance cognitive domain, while controlling for VLS.

METHODS

Participants included 205 (median age = 44 years; 77% males; HIV-/METH- n = 67; HIV+/METH - n = 49; HIV-/METH+ n = 36; HIV+/METH+ n = 53) individuals enrolled in the Translational Methamphetamine AIDS Research Center, who completed Conners' and the 5-Choice continuous performance tests (CPTs).

RESULTS

METH participants exhibited deficits in sustained attention and vigilance; however, these effects were not significant after excluding participants who had a positive urine toxicology screen for methamphetamine. Controlling for VLS, PWH did not have worse sustained attention and vigilance, but consistently displayed slower reaction times across blocks, relative to HIV- participants. There was no HIV x METH interaction on sustained attention and vigilance.

CONCLUSIONS

Recent methamphetamine use among METH people and detectable viral loads are detrimental to sustained attention and vigilance. These findings highlight the need for prompt diagnosis of HIV and initiation of antiretroviral therapy, and METH use interventions.

Human Immunodeficiency Virus Type 1 and Methamphetamine-Mediated Mitochondrial Damage and Neuronal Degeneration in Human Neurons

Methamphetamine, a potent psychostimulant, is a highly addictive drug commonly used by persons living with HIV (PLWH), and its use can result in cognitive impairment and memory deficits long after its use is discontinued. Although the mechanism(s) involved with persistent neurological deficits is not fully known, mitochondrial dysfunction is a key component in methamphetamine neuropathology. Specific mitochondrial autophagy (mitophagy) and mitochondrial fusion and fission are protective quality control mechanisms that can be dysregulated in HIV infection, and the use of methamphetamine can further negatively affect these protective cellular mechanisms. Here, we observed that treatment of human primary neurons (HPNs) with methamphetamine and HIV gp120 and Tat increase dynamin-related protein 1 (DRP1)-dependent mitochondrial fragmentation and neuronal degeneration. Methamphetamine and HIV proteins increased microtubule-associated protein 1 light chain 3 beta-II (LC3B-II) lipidation and induced sequestosome 1 (SQSTM1, p62) translocation to damaged mitochondria. Additionally, the combination inhibited autophagic flux, increased reactive oxygen species (ROS) production and mitochondrial damage, and reduced microtubule-associated protein 2 (MAP2) dendrites in human neurons. N-Acetylcysteine (NAC), a strong antioxidant and ROS scavenger, abrogated DRP1-dependent mitochondrial fragmentation and neurite degeneration. Thus, we show that methamphetamine combined with HIV proteins inhibits mitophagy and induces neuronal damage, and NAC reverses these deleterious effects on mitochondrial function.IMPORTANCE Human and animal studies show that HIV infection, combined with the long-term use of psychostimulants, increases neuronal stress and the occurrence of HIV-associated neurocognitive disorders (HAND). On the cellular level, mitochondrial function is critical for neuronal health. In this study, we show that in human primary neurons, the combination of HIV proteins and methamphetamine increases oxidative stress, DRP1-mediated mitochondrial fragmentation, and neuronal injury manifested by a reduction in neuronal network and connectivity. The use of NAC, a potent antioxidant, reversed the neurotoxic effects of HIV and methamphetamine, suggesting a novel approach to ameliorate the effects of HIV- and methamphetamine-associated cognitive deficits.

An update on drug-drug interactions between antiretroviral therapies and drugs of abuse in HIV systems

INTRODUCTION

While considerable progress has been made in the fight against HIV/AIDS, to date there has not been a cure, and millions of people around the world are currently living with HIV/AIDS. People living with HIV/AIDS have substance abuse disorders at higher rates than non-infected individuals, which puts them at an increased risk of drug-drug interactions.

AREAS COVERED

Potential drug-drug interactions are reviewed for a variety of potential drugs of abuse, both licit and illicit. These drugs include alcohol, cigarettes or other nicotine delivery systems, methamphetamine, cocaine, opioids, and marijuana. Potential interactions include decreased adherence, modulation of drug transporters, or modulation of metabolic enzymes. We also review the relative incidence of the use of these drugs of abuse in People living with HIV/AIDS.

EXPERT OPINION

Despite considerable improvements in outcomes, disparities in outcomes between PLWHA who use drugs of abuse, vs those who do not still exist. It is of critical necessity to improve outcomes in these patients and to work with them to stop abusing drugs of abuse.

Characterising the increasing prevalence of crystal methamphetamine use in Vancouver, Canada, from 2006-2017: A gender-based analysis

INTRODUCTION

Methamphetamine use is increasing in North America and is associated with numerous negative health effects and social harms. As drug-related harms are often gendered, this study sought to examine the differential impacts of gender on the trends, risk factors and health implications of crystal methamphetamine use among a Canadian cohort of people with high rates of injection polysubstance use.

METHODS

Data were collected from two prospective cohorts of people who inject drugs in Vancouver, Canada. We examined trends in reported crystal methamphetamine use from 2006-2017 using the Cochrane-Armitage test for trend. We used multivariable generalised estimating equations, stratified by gender, to determine independent risk factors and health outcomes associated with crystal methamphetamine use.

RESULTS

In total, 1984 participants were included in the study, including 694 (35%) women. The prevalence of reported crystal methamphetamine use within the previous 6 months rose from 19% in 2006 to 36% in 2017, with a rise seen in both genders (P < 0.001). Reported crystal methamphetamine use was associated with numerous risk behaviours and drug-related harms in both genders, and in women it was associated with an increase in experiences of sexual violence (adjusted odds ratio 1.64, 95% confidence interval 1.18, 2.27).

CONCLUSIONS

These findings demonstrate the rising prevalence of reported crystal methamphetamine use in Vancouver in a cohort with high rates of polysubstance use. This work highlights drug and sex-related risk behaviours associated with crystal methamphetamine use for both genders, and underscores the need to develop strategies to address the growing use of crystal methamphetamine.

The OATH Syndemic: opioids and other substances, aging, alcohol, tobacco, and HIV

PURPOSE OF REVIEW

Persons living with HIV (PLWH) are aging, continue to use alcohol and other substances, and experience age-associated adverse effects. We explore a new syndemic: OATH (opioids and other substances, aging, alcohol, tobacco, and HIV).

RECENT FINDINGS

Frailty and falls are important problems that affect the health status of PLWH who continue to use alcohol and other substances. HIV, alcohol and other substance use, and aging each contributes to inflammaging. Multimorbidity and polypharmacy are also important pathways as alcohol and other substances interact with prescribed medications resulting in adverse-drug interactions leading to potentially serious consequences. Social conditions including racism, poverty, sex bias, stress, and stigma contribute to the existence and persistence of this syndemic.

SUMMARY

Substance use, HIV, and aging are linked in a new syndemic (OATH) that drives age-related outcomes such as frailty and falls. We need to expand our understanding of the 'healthcare team' so that we include social and political advocates who can support necessary structural change. Treatment of substance use should be better incorporated into the management of HIV, including a focus on potential medication/substance interactions. Finally, we need to explore treatment of frailty rather than individual manifestations of frailty (e.g., atherosclerosis, neurodegeneration).

An initial randomized controlled trial of behavioral activation for treatment of concurrent crystal methamphetamine dependence and sexual risk for HIV acquisition among men who have sex with men

Men who have sex with men (MSM) continue to be the largest risk group for HIV infections in the U.S., where crystal methamphetamine abuse heightens risk for HIV infection through greater engagement in condomless anal sex (CAS). Existing treatments lack attention to replacement activities or the role of depressed mood. Behavioral activation (BA) is an evidence-based approach for depression that involves identifying and participating in pleasurable, goal-directed activities. We hypothesize, for MSM abusing crystal methamphetamine, re-learning how to engage in non-drug-using aspects of life would facilitate their ability to benefit from sexual risk reduction (SRR) counseling. Project IMPACT was a pilot randomized-controlled-trial. Forty-six MSM at sexual risk of acquiring HIV who met DSM-IV criteria for crystal methamphetamine dependence were enrolled. Of those MSM, 41 were randomized: 21 were assigned to the intervention, two sessions of SRR, ten sessions of BA with SRR, and one session of relapse prevention; 20 participants were assigned to a control condition (two sessions of SRR). At the acute post-intervention visit, intervention participants reported an average of 3.2 CAS acts with men who were HIV-infected or whose status they did not know, compared to 4.5 among control participants (β = -0.36; 95% CI: -0.69, -0.02; p = 0.035). At the 6-month post-intervention visit, intervention participants reported 1.1 CAS acts with men who were HIV-infected or whose status they did not know compared to 2.8 among control participants (β = -0.95; 95% CI: -1.44, -0.46; p < 0.0001). Similarly, intervention participants reported 1.0 CAS acts under the influence of crystal methamphetamine with men who were HIV-infected or whose status they did not know compared to 2.5 among control participants (β = -0.87; 95% CI: -1.38, -0.36; p = 0.0005). Lastly, intervention participants reported more continuous days abstaining from crystal methamphetamine compared to control (50.1 vs. 39.0, respectively) (β = 0.25; 95% CI: 0.16, 0.34; p < 0.0001). Findings are encouraging, provide evidence of feasibility and acceptability, and demonstrate initial efficacy for reducing sexual risk for HIV and crystal methamphetamine use.

Speed kills: Associations between methamphetamine use, HIV infection, tobacco use, and accelerated mortality among gay and bisexual men in Los Angeles, CA 20years after methamphetamine dependence treatment

BACKGROUND

To better characterize mortality among methamphetamine users, we estimated rates of all-cause mortality by HIV serostatus and smoking history in gay and bisexual men (GBM) treated for methamphetamine dependence, and explored associated clinical and socio-behavioral characteristics.

METHODS

We searched public records to identify deaths among men screened between 1998-2000 for a trial of outpatient therapy for GBM with methamphetamine dependence. Crude mortality rates (CMRs) were calculated, and standardized mortality ratios (SMRs) estimated, comparing data with historical information from CDC WONDER. Associations of mortality with HIV infection, tobacco use, and other factors were explored using Kaplan-Meier survival analysis and Cox proportional hazards models.

RESULTS

Of 191 methamphetamine-dependent GBM (median age 35 years; majority Caucasian), 62.8% had HIV infection, and 31.4% smoked tobacco at baseline. During the 20-year follow-up period, 12.6% died. Relative to controls, methamphetamine-dependent GBM had a three-fold higher 20-year SMR: 3.39, 95% CI: 2.69-4.09. Especially high mortality was observed among participants reporting tobacco use (adjusted HR 3.48, 95% CI: 1.54-7.89), club drug use prior to starting methamphetamine (2.63, 1.15-6.00), or other clinical diagnoses at baseline (3.89, 1.15-13.22). At 20 years, the CMR for HIV infected participants (7.7 per 1000 PY) was 1.5 times that for men without HIV (5.2 per 1000 PY; p = 0.22) and there was a 5-fold difference in CMRs for HIV infected tobacco smokers (16.9 per 1000 PY) compared to non-smokers (3.4 per 1000 PY; p < 0.01).

CONCLUSION

In our sample of methamphetamine-dependent GBM, concomitant HIV infection and tobacco use were associated with dramatic increases in mortality.

Methamphetamine functions as a novel CD4+ T-cell activator via the sigma-1 receptor to enhance HIV-1 infection

Methamphetamine (Meth) exacerbates HIV-1 pathobiology by increasing virus transmission and replication and accelerating clinical progression to AIDS. Meth has been shown to alter the expression of HIV-1 co-receptors and impair intrinsic resistance mechanisms of immune cells. However, the exact molecular mechanisms involved in augmenting HIV-1 replication in T-cells are still not yet clear. Here, we demonstrate that pretreatment with Meth of CD4+ T-cells enhanced HIV-1 replication. We observed upregulation of CD4+ T-cell activation markers and enhanced expression of miR-34c-5p and miR-155 in these cells. Further, we noted activation of the sigma-1 receptor and enhanced intracellular Ca2+ concentration and cAMP release in CD4+ T-cells upon Meth treatment, which resulted in increased phosphorylation and nuclear translocation of transcription factors NFκB, CREB, and NFAT1. Increased gene expression of IL-4 and IL-10 was also observed in Meth treated CD4+ T-cells. Moreover, proteasomal degradation of Ago1 occurred upon Meth treatment, further substantiating the drug as an activator of T-cells. Taken together, these findings show a previously unreported mechanism whereby Meth functions as a novel T-cell activator via the sigma-1 signaling pathway, enhancing replication of HIV-1 with expression of miR-34c-5p, and transcriptional activation of NFκB, CREB and NFAT1.

Risk Factors and Pathogenesis of HIV-Associated Neurocognitive Disorder: The Role of Host Genetics

Neurocognitive impairments associated with human immunodeficiency virus (HIV) infection remain a considerable health issue for almost half the people living with HIV, despite progress in HIV treatment through combination antiretroviral therapy (cART). The pathogenesis and risk factors of HIV-associated neurocognitive disorder (HAND) are still incompletely understood. This is partly due to the complexity of HAND diagnostics, as phenotypes present with high variability and change over time. Our current understanding is that HIV enters the central nervous system (CNS) during infection, persisting and replicating in resident immune and supporting cells, with the subsequent host immune response and inflammation likely adding to the development of HAND. Differences in host (human) genetics determine, in part, the effectiveness of the immune response and other factors that increase the vulnerability to HAND. This review describes findings from studies investigating the role of human host genetics in the pathogenesis of HAND, including potential risk factors for developing HAND. The similarities and differences between HAND and Alzheimer's disease are also discussed. While some specific variations in host genes regulating immune responses and neurotransmission have been associated with protection or risk of HAND development, the effects are generally small and findings poorly replicated. Nevertheless, a few specific gene variants appear to affect the risk for developing HAND and aid our understanding of HAND pathogenesis.

Inter-trial variability in brain activity as an indicator of synergistic effects of HIV-1 and drug abuse

BACKGROUND

The objective of this investigation was to detect evidence of the synergism in the effects of HIV-1 and drug abuse on brain function that has been hypothesized but rarely shown. The investigation incorporated several noteworthy improvements in the approach. It used urine toxicology tests to exclude participants complicated by recent methadone use and illicit drug use. Also, it defined drug abuse on a scale that considered symptom severity. Most importantly, it examined inter-trial variability in brain activity as a potentially more sensitive indicator of group differences and functional impairment than the across-trial average.

METHODS

173 participants were assigned to groups defined by their HIV-1 serostatus and Drug Abuse Screening Test score (DAST < vs. > = 6). They completed a simple letter discrimination task including rare target and rare nontarget stimuli. Event-related electroencephalographic responses and key press responses were measured on each trial. During a separate assessment, posturographic measures were recorded.

RESULTS

The inter-trial standard deviation of P300-like activity was superior to the mean amplitude of this activity in differentiating the groups. Unlike the mean, it revealed synergistic statistical effects of HIV and drug abuse. It also correlated significantly with static ataxia.

CONCLUSIONS

Inter-trial variability in P300-like activity is a useful marker for detecting subtle and episodic disruptions in brain function. It demonstrates greater sensitivity than the mean amplitude for detecting differences across groups. Also, as a putative indicator of a disruption in the attentional monitoring of behavior, it predicts subtle impairments in gross motor function.

Methamphetamine-associated dysregulation of the hypothalamic-pituitary-thyroid axis

Methamphetamine and HIV impair thyroid function, but few studies have investigated their combined effects on thyroid dysregulation. This study examined the associations of methamphetamine use alone and in combination with HIV on thyroid function among men in South Florida. Measures of thyroid function in methamphetamine-using, HIV-infected (METH+HIV+; n = 127) and HIV-negative (METH+HIV-; n = 46) men who have sex with men (MSM) were compared to non-methamphetamine-using, HIV-negative men (METH-HIV-; n = 136). Thyroid function was dysregulated in methamphetamine-using MSM, irrespective of HIV status. Both meth-using groups had greater odds of abnormal thyroid stimulating hormone levels and significantly higher mean free triiodothyronine (T3) levels. Elevated free T3 was associated with greater depressive symptoms. Overall, outcomes have important implications for assessment of thyroid function in methamphetamine users, particularly among those presenting with depression.

Colon dysregulation in methamphetamine self-administering HIV-1 transgenic rats

The integrity and function of the gut is impaired in HIV-infected individuals, and gut pathogenesis may play a role in several HIV-associated disorders. Methamphetamine is a popular illicit drug abused by HIV-infected individuals. However, the effect of methamphetamine on the gut and its potential to exacerbate HIV-associated gut pathology is not known. To shed light on this scenario, we evaluated colon barrier pathology in a rat model of the human comorbid condition. Intestinal barrier integrity and permeability were assessed in drug-naïve Fischer 344 HIV-1 transgenic (Tg) and non-Tg rats, and in Tg and non-Tg rats instrumented with jugular cannulae trained to self-administer methamphetamine or serving as saline-yoked controls. Intestinal permeability was determined by measuring the urine content of orally gavaged sugars. Intestinal barrier integrity was evaluated by immunoblotting or immunofluorescence of colon claudin-1 and zonula occludens-1 (ZO-1), two major tight junction proteins that regulate gut epithelial paracellular permeability. Both non-Tg and Tg rats self-administered moderate amounts of methamphetamine. These amounts were sufficient to increase colon permeability, reduce protein level of claudin-1, and reduce claudin-1 and ZO-1 immunofluorescence in Tg rats relative to non-Tg rats. Methamphetamine decreased tight junction immunofluorescence in non-Tg rats, with a similar, but non-significant trend observed in Tg rats. However, the effect of methamphetamine on tight junction proteins was subthreshold to gut leakiness. These findings reveal that both HIV-1 proteins and methamphetamine alter colon barrier integrity, and indicate that the gut may be a pathogenic site for these insults.

Drug Use is Associated with Anti-CD4 IgG-mediated CD4+ T Cell Death and Poor CD4+ T Cell Recovery in Viral-suppressive HIV-infected Individuals Under Antiretroviral Therapy

BACKGROUND

The role and mechanism of drug use or abuse in Antiretroviral Therapy (ART)-treated HIV disease are not completely known.

METHODS

To investigate the impact of drug use on HIV pathogenesis without confounding by HIV replication and ART adherence, we first analyzed the data from our clinical database in 103 HIV+ subjects with viral-suppressed ART treatment by a multiple regression test.

RESULTS

We found that HIV+ drug users had lower CD4+ T cell counts but higher CD8+ T cell counts compared to HIV+ non-drug users, and both drug use and nadir CD4+ T cell counts was independently associated with CD4+ T cell recovery after controlling for sex and age. Next, we enrolled individuals from four study groups, HIV-negative and HIV+ subjects without any substance use, HIV-negative and HIV+ subjects with current illicit drug use (either non-injection cocaine or cannabis). All HIV+ subjects were viral-suppressed with ART treatment (≥ 2 years). Notably, HIV+ drug users had increased plasma anti-CD4 IgG levels compared to the other three study groups which were inversely correlated with decreased CD4+ T cell counts only in HIV+ drug users. There was a significant increase in CD4+ T cell recovery following ART in HIV+ non-drug users but not in HIV+ drug users. Anti-CD4 IgGs purified from plasma of HIV+ drug users induced CD4+ T cell death in vitro through Antibody-Dependent Cytotoxicity (ADCC).

CONCLUSION

These results suggest that drug use prevents immune reconstitution in HIV-infected individuals despite long-term ART treatment and viral suppression.

Methamphetamine potentiates HIV-1 gp120-mediated autophagy via Beclin-1 and Atg5/7 as a pro-survival response in astrocytes

Methamphetamine (METH), a commonly used controlled substance, is known to exacerbate neuropathological dysfunction in HIV-infected individuals. The neuropathological manifestation results from cell death or dysfunction in the central nervous system (CNS) wherein autophagy is expected to have an important role. Autophagy is generally considered protective during deprivation/stress. However, excessive autophagy can be destructive, leading to autophagic cell death. This study was designed to investigate if METH and HIV-1 gp120 interact to induce autophagy in SVGA astrocytes, and whether autophagy is epiphenomenal or it has a role in METH- and gp120-induced cytotoxicity. We found that METH and gp120 IIIb caused an increase in LC3II level in astrocytes in a dose- and time-dependent manner, and the level of LC3II was further increased when the cells were treated with METH and gp120 IIIb in combination. Next, we sought to explore the mechanism by which METH and gp120 induce the autophagic response. We found that METH induces autophagy via opioid and metabotropic glutamate receptor type 5 (mGluR5) receptors. Other than that, signaling proteins Akt, mammalian target of rapamycin (mTOR), Beclin-1, Atg5 and Atg7 were involved in METH and gp120-mediated autophagy. In addition, long-term treatment of METH and gp120 IIIb resulted in cell death, which was exacerbated by inhibition of autophagy. This suggests that autophagy functions as a protective response against apoptosis caused by METH and gp120. This study is novel and clinically relevant because METH abuse among HIV-infected populations is highly prevalent and is known to cause exacerbated neuroAIDS.

Effects of HIV and Methamphetamine on Brain and Behavior: Evidence from Human Studies and Animal Models

Methamphetamine (Meth) use is frequent among HIV-infected persons. Combined HIV and Meth insults may exacerbate neural injury in vulnerable neuroanatomic structures or circuitries in the brain, leading to increased behavioral disturbance and cognitive impairment. While acute and chronic effects of Meth in humans and animal models have been studied for decades, the neurobehavioral effects of Meth in the context of HIV infection are much less explored. In-depth understanding of the scope of neurobehavioral phenotypes and mechanisms in HIV/Meth intersection is needed. The present report summarizes published research findings, as well as unpublished data, in humans and animal models with regard to neurobehavioral disturbance, neuroimaging, and neuropathology, and in vitro experimental systems, with an emphasis on findings emerging from the National Institute on Drug Abuse (NIDA) funded Translational Methamphetamine AIDS Research Center (TMARC). Results from human studies and animal (primarily HIV-1 gp120 transgenic mouse) models thus far suggest that combined HIV and Meth insults increase the likelihood of neural injury in the brain. The neurobehavioral effects include cognitive impairment and increased tendencies toward impaired behavioral inhibition and social cognition. These impairments are relevant to behaviors that affect personal and social risks, e.g. worse medication adherence, riskier behaviors, and greater likelihood of HIV transmission. The underlying mechanisms may include electrochemical changes in neuronal circuitries, injury to white matter microstructures, synaptodendritic damage, and selective neuronal loss. Utilization of research methodologies that are valid across species is instrumental in generating new knowledge with clinical translational value.

Methamphetamine compromises gap junctional communication in astrocytes and neurons

Methamphetamine (meth) is a central nervous system (CNS) stimulant that results in psychological and physical dependency. The long-term effects of meth within the CNS include neuronal plasticity changes, blood-brain barrier compromise, inflammation, electrical dysfunction, neuronal/glial toxicity, and an increased risk to infectious diseases including HIV. Most of the reported meth effects in the CNS are related to dysregulation of chemical synapses by altering the release and uptake of neurotransmitters, especially dopamine, norepinephrine, and epinephrine. However, little is known about the effects of meth on connexin (Cx) containing channels, such as gap junctions (GJ) and hemichannels (HC). We examined the effects of meth on Cx expression, function, and its role in NeuroAIDS. We found that meth altered Cx expression and localization, decreased GJ communication between neurons and astrocytes, and induced the opening of Cx43/Cx36 HC. Furthermore, we found that these changes in GJ and HC induced by meth treatment were mediated by activation of dopamine receptors, suggesting that dysregulation of dopamine signaling induced by meth is essential for GJ and HC compromise. Meth-induced changes in GJ and HC contributed to amplified CNS toxicity by dysregulating glutamate metabolism and increasing the susceptibility of neurons and astrocytes to bystander apoptosis induced by HIV. Together, our results indicate that connexin containing channels, GJ and HC, are essential in the pathogenesis of meth and increase the sensitivity of the CNS to HIV CNS disease. Methamphetamine (meth) is an extremely addictive central nervous system stimulant. Meth reduced gap junctional (GJ) communication by inducing internalization of connexin-43 (Cx43) in astrocytes and reducing expression of Cx36 in neurons by a mechanism involving activation of dopamine receptors (see cartoon). Meth-induced changes in Cx containing channels increased extracellular levels of glutamate and resulted in higher sensitivity of neurons and astrocytes to apoptosis in response to HIV infection.

HIV-1, methamphetamine and astrocytes at neuroinflammatory Crossroads

As a popular psychostimulant, methamphetamine (METH) use leads to long-lasting, strong euphoric effects. While METH abuse is common in the general population, between 10 and 15% of human immunodeficiency virus-1 (HIV-1) patients report having abused METH. METH exacerbates the severity and onset of HIV-1-associated neurocognitive disorders (HAND) through direct and indirect mechanisms. Repetitive METH use impedes adherence to antiretroviral drug regimens, increasing the likelihood of HIV-1 disease progression toward AIDS. METH exposure also directly affects both innate and adaptive immunity, altering lymphocyte numbers and activity, cytokine signaling, phagocytic function and infiltration through the blood brain barrier. Further, METH triggers the dopamine reward pathway and leads to impaired neuronal activity and direct toxicity. Concurrently, METH and HIV-1 alter the neuroimmune balance and induce neuroinflammation, which modulates a wide range of brain functions including neuronal signaling and activity, glial activation, viral infection, oxidative stress, and excitotoxicity. Pathologically, reactive gliosis is a hallmark of both HIV-1- and METH-associated neuroinflammation. Significant commonality exists in the neurotoxic mechanisms for both METH and HAND; however, the pathways dysregulated in astroglia during METH exposure are less clear. Thus, this review highlights alterations in astrocyte intracellular signaling pathways, gene expression and function during METH and HIV-1 comorbidity, with special emphasis on HAND-associated neuroinflammation. Importantly, this review carefully evaluates interventions targeting astrocytes in HAND and METH as potential novel therapeutic approaches. This comprehensive overview indicates, without a doubt, that during HIV-1 infection and METH abuse, a complex dialog between all neural cells is orchestrated through astrocyte regulated neuroinflammation.