Crystal Methamphetamine, Its Analogues, and HIV Infection: Medical and Psychiatric Aspects of a New Epidemic

The association between methamphetamine use and number of sexual partners in men who have sex with men: a systematic review and meta-analysis

Background

Methamphetamine use in men who have sex with men population is significantly higher than that in the general population. Meth use can cause high-risk sexual behaviors, such as having sex with a variety of sexual partners. The aim of this study was to determine the association between meth use and the number of sexual partners in MSM.

Methods

Searching international databases (PubMed (Medline), Scopus, Web of Sciences, Embase (Elsevier), PsycInfo (Ovid), Cochrane CENTRAL (Ovid)) until March 2021 was performed in this meta-analysis using appropriate keywords terms to identify related articles. After retrieving articles in these databases, screening was performed based on the title, abstract and full text of the articles, and the final related studies were selected and evaluated using the Newcastle Ottawa scale checklist.

Results

The sample size consisted 18,455 people in this study, including four cohort studies with a sample size of 15,026 MSM and four case–control studies with a sample size of 3429 MSM. The results of meta-analysis showed that meth use increased the number of sexual partners in MSM (RR: 3.70; % 95 CI: 2.04—6.70). The results of subgroup analyze based on the number of sexual partners showed that in MSM taking meth, the risks of having one to three, four to five, and six or more than six sexual partners were respectively 2.82, 2.98 and 5.89 times higher than those in MSM who did not take meth.

Conclusion

The results showed that meth uses in MSM increased the number of their sexual partners. Due to the fact that increasing the number of sexual partners and high-risk sexual behaviors increase the risk of contracting sexually transmitted diseases such as HIV, it is necessary to adopt control programs to prevent meth use by this group, or to implement programs of reduction in the risk of STIs for this group.

Methamphetamine facilitates HIV infection of primary human monocytes through inhibiting cellular viral restriction factors

Background

Methamphetamine (METH), a potent addictive psychostimulant, is highly prevalent in HIV-infected individuals. Clinically, METH use is implicated in alteration of immune system and increase of HIV spread/replication. Therefore, it is of importance to examine whether METH has direct effect on HIV infection of monocytes, the major target and reservoir cells for the virus.

Results

METH-treated monocytes were more susceptible to HIV infection as evidenced by increased levels of viral proteins (p24 and Pr55Gag) and expression of viral GAG gene. In addition, using HIV Bal with luciferase reporter gene (HIV Bal-eLuc), we showed that METH-treated cells expressed higher luciferase activities than untreated monocytes. Mechanistically, METH inhibited the expression of IFN-λ1, IRF7, STAT1, and the antiviral IFN-stimulated genes (ISGs: OAS2, GBP5, ISG56, Viperin and ISG15). In addition, METH down-regulated the expression of the HIV restriction microRNAs (miR-28, miR-29a, miR-125b, miR-146a, miR-155, miR-223, and miR-382).

Conclusions

METH compromises the intracellular anti-HIV immunity and facilitates HIV replication in primary human monocytes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00703-4.

Use of methamphetamine and alcohol among people with opioid use disorder and HIV in Vietnam: a qualitative study

BACKGROUND

Heroin use continues to drive HIV transmission in Vietnam, but methamphetamine and alcohol use are growing rapidly and, as in other countries, polysubstance use is widespread. The objective of this study was to understand the interplay between heroin, methamphetamine, and alcohol use among people with opioid use disorder (OUD) and HIV in Vietnam.

METHODS

We conducted 44 in-depth, face-to-face qualitative interviews with people with OUD and HIV who participated in the BRAVO trial of buprenorphine versus methadone in five Vietnam HIV clinics. Interviews probed participants' experiences of heroin, methamphetamine, and alcohol use and their interplay with HIV/OUD treatment. Interviews were professionally transcribed and analyzed using a thematic analysis approach.

RESULTS

Of 44 participants interviewed 42 were male, on average 38.8 years of age, with 30 reporting a history of methamphetamine use and 33 reporting a history of alcohol use. Several themes emerged: 1) Methamphetamine and alcohol were perceived to have lower addiction potential than heroin 2) Social settings were key facilitators of alcohol and methamphetamine use 3) Some participants, but not all, used methamphetamine to help quit heroin 4) Consuming alcohol blunted the effects of heroin, while paradoxically serving as a catalyst for heroin use 5) Use of methamphetamine was perceived by many participants to be incompatible with treatment for HIV.

CONCLUSIONS

Participant experiences reflected a significant impact of polysubstance use on treatment of HIV and OUD. Patterns of polysubstance use are subject to common preconceptions of alcohol and methamphetamine as having a low addictive potential, and these substances are deeply enmeshed in the social life of many people with OUD in Vietnam. Interventions to address complex social norms and potential harms of polysubstance use are urgently needed as the population of people receiving medication for OUD (MOUD) increases in Vietnam and globally.

TRIAL REGISTRATION

BRAVO - NCT01936857 , September 2013.

Frequent Methicillin-Resistant Staphylococcus aureus Introductions Into an Inner-city Jail: Indications of Community Transmission Networks

BACKGROUND

Jails may facilitate spread of methicillin-resistant Staphylococcus aureus (MRSA) in urban areas. We examined MRSA colonization upon entrance to a large urban jail to determine if there are MRSA transmission networks preceding incarceration.

METHODS

Males incarcerated in Cook County Jail (Chicago) were enrolled, with enrichment for people living with human immunodeficiency virus (PLHIV), within 72 hours of intake. Surveillance cultures assessed prevalence of MRSA colonization. Whole-genome sequencing (WGS) identified preincarceration transmission networks.We examined methicillin-resistant Staphylococcus aureus (MRSA) isolates to determine if there are transmission networks that precede incarceration. A large proportion of individuals enter jail colonized with MRSA. Molecular epidemiology and colonization risk factors provide clues to community reservoirs for MRSA.

RESULTS

There were 718 individuals (800 incarcerations) enrolled; 58% were PLHIV. The prevalence of MRSA colonization at intake was 19%. In multivariate analysis, methamphetamine use, unstable housing, current/recent skin infection, and recent injection drug use were predictors of MRSA. Among PLHIV, recent injection drug use, current skin infection, and HIV care at outpatient clinic A that emphasizes comprehensive care to the lesbian, gay, bisexual, transgender community were predictors of MRSA. Fourteen (45%) of 31 detainees with care at clinic A had colonization. WGS revealed that this prevalence was not due to clonal spread in clinic but rather to an intermingling of distinct community transmission networks. In contrast, genomic analysis supported spread of USA500 strains within a network. Members of this USA500 network were more likely to be PLHIV (P < .01), men who have sex with men (P < .001), and methamphetamine users (P < .001).

CONCLUSIONS

A large proportion of individuals enter jail colonized with MRSA. Molecular epidemiology and colonization risk factors provide clues to identify colonized detainees entering jail and potential community reservoirs of MRSA.

Beneficial and Adverse Effects of cART Affect Neurocognitive Function in HIV-1 Infection: Balancing Viral Suppression against Neuronal Stress and Injury

HIV-associated neurocognitive disorders (HAND) persist despite the successful introduction of combination antiretroviral therapy (cART). While insufficient concentration of certain antiretrovirals (ARV) may lead to incomplete viral suppression in the brain, many ARVs are found to cause neuropsychiatric adverse effects, indicating their penetration into the central nervous system (CNS). Several lines of evidence suggest shared critical roles of oxidative and endoplasmic reticulum stress, compromised neuronal energy homeostasis, and autophagy in the promotion of neuronal dysfunction associated with both HIV-1 infection and long-term cART or ARV use. As the lifespans of HIV patients are increased, unique challenges have surfaced. Longer lives convey prolonged exposure of the CNS to viral toxins, neurotoxic ARVs, polypharmacy with prescribed or illicit drug use, and age-related diseases. All of these factors can contribute to increased risks for the development of neuropsychiatric conditions and cognitive impairment, which can significantly impact patient well-being, cART adherence, and overall health outcome. Strategies to increase the penetration of cART into the brain to lower viral toxicity may detrimentally increase ARV neurotoxicity and neuropsychiatric adverse effects. As clinicians attempt to control peripheral viremia in an aging population of HIV-infected patients, they must navigate an increasingly complex myriad of comorbidities, pharmacogenetics, drug-drug interactions, and psychiatric and cognitive dysfunction. Here we review in comparison to the neuropathological effects of HIV-1 the available information on neuropsychiatric adverse effects and neurotoxicity of clinically used ARV and cART. It appears altogether that future cART aiming at controlling HIV-1 in the CNS and preventing HAND will require an intricate balancing act of suppressing viral replication while minimizing neurotoxicity, impairment of neurocognition, and neuropsychiatric adverse effects. Graphical abstract Schematic summary of the effects exerted on the brain and neurocognitive function by HIV-1 infection, comorbidities, psychostimulatory, illicit drugs, therapeutic drugs, such as antiretrovirals, the resulting polypharmacy and aging, as well as the potential interactions of all these factors.

Beyond Overdose: Drug-Related Deaths in People With and Without HIV in San Francisco, 2007-2018

Despite elevated mortality in people with HIV (PWH) using drugs, drug-related deaths are poorly characterized. Among 6764 drug-related deaths, methamphetamine was more common in PWH than others. One in 4 deaths in PWH involved acute infection. Combatting mortality in PWH who use drugs should include stimulant-specific and infection prevention efforts.

Identification of the Differentially Expressed Genes Involved in the Synergistic Neurotoxicity of an HIV Protease Inhibitor and Methamphetamine

BACKGROUND

The abuse of psychostimulants such as methamphetamine (METH) is common in human immunodeficiency virus (HIV)-infected individuals. Acquired immunodeficiency syndrome (AIDS) patients taking METH and antiretroviral drugs could suffer severe neurologic damage and cognitive impairment.

OBJECTIVE

To reveal the underlying neuropathologic mechanisms of an HIV protease inhibitor (PI) combined with METH, growth-inhibition tests of dopaminergic cells and RNA sequencing were performed.

METHODS

A combination of METH and PI caused more growth inhibition of dopaminergic cells than METH alone or a PI alone. Furthermore, we identified differentially expressed gene (DEG) patterns in the METH vs. untreated cells (1161 genes), PI vs. untreated cells (16 genes), METH-PI vs. PI (3959 genes), and METH-PI vs. METH groups (14 genes).

RESULTS

The DEGs in the METH-PI co-treatment group were verified in the brains of a mouse model using quantitative polymerase chain reaction and were involved mostly in the regulatory functions of cell proliferation and inflammation.

CONCLUSION

Such identification of key regulatory genes could facilitate the study of their neuroprotective potential in the users of METH and PIs.

Postmortem Study of Molecular and Histological Changes in the CA1 Hippocampal Region of Chronic Methamphetamine User

Methamphetamine (Meth) is recognized as one of the most important new distributed abused drug that causes severe damage to the different parts of the brain, especially hippocampus. Previous studies have demonstrated that Meth can induce apoptosis and cell death in the brain. In this study, we evaluated the long-term effects of Meth abuse in the CA1 region of postmortem hippocampus. Postmortem molecular and histological analysis was performed for five non-addicted subjects and five Meth addicted ones. Iba-1 (microglia) and glial fibrillary acidic protein, GFAP (astrocytes) expression were assayed by western blotting and immunohistochemistry (IHC) methods. Histopathological assessment was done with stereological counts of hippocampal cells stained with hematoxylin and eosin (H and E). Tunel staining was used to detect DNA damage in human brains. In addition, protein-protein interaction analysis network was investigated. Western blotting and immunohistochemistry assay showed overexpression of GFAP and Iba-1 protein in the CA1 hippocampal region of Meth users’ brain. Stereological analysis in the CA1 region revealed increased neuron degeneration. Furthermore, significant apoptosis and cell death were confirmed by Tunel assay in the hippocampus. The prominent role of TLR4, IL1B, CASP1, and NLRP3 in the molecular mechanism of Meth was highlighted via PPI network analysis. Chronic Meth use can induce GFAP and Iba-1 upregulation and neuronal apoptosis in the CA1 region of the postmortem hippocampus.

Intersection of HIV and community-associated methicillin-resistant Staphylococcus aureus

The epidemiology of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has evolved over the past approximately 20 years, with certain populations appearing to have disproportionate risk. Of concern is the potential worsening of S. aureus infections in light of the continued opioid crisis. This review will discuss how CA-MRSA has significantly impacted HIV-infected individuals and address additional factors and populations that are associated with increased risk for MRSA. It will review therapeutic options and infection control strategies as well as highlight how whole genome sequencing can be used to extend traditional epidemiologic analysis and ultimately, inform infection prevention efforts. Continued work identifying those at the highest risk for MRSA, what the best infection prevention settings are in community settings and how to effectively implement and target these strategies is needed. Ultimately, infection control efforts will likely need to extend beyond healthcare settings to effectively and sustainably reduce MRSA infections.

Use of alcohol swabs to clean injecting sites among people who regularly inject drugs in Australia

INTRODUCTION AND AIMS

Cleaning drug injection sites with alcohol swabs prior to injecting reduces risk of abscesses and other skin and soft tissue infections (SSTI). Better understanding of swabbing behaviours can inform interventions to improve injecting hygiene. We aimed to determine the socio-demographic, drug use and injecting risk exposure correlates of swabbing prior to injecting and reasons for not swabbing.

DESIGN AND METHODS

The Illicit Drug Reporting System recruited participants who had injected drugs at least monthly in the past six months in June-July 2017 from all Australian capital cities via needle and syringe programs and word-of-mouth. A structured interview was used to collect information on drug use and related behaviour, as well as swabbing practices. Logistic regression was used to identify factors associated with not swabbing at last injection.

RESULTS

Of 853 respondents, one-quarter (26%) reported that they did not swab prior to their last injection. In adjusted analyses, crystal methamphetamine as the last drug injected, past month receptive or distributive syringe sharing, and past month re-use of one's own needle were significantly associated with not swabbing at last injection. Among participants who did not swab at last injection, swabbing was frequently considered unnecessary and a small number disliked using alcohol swabs.

DISCUSSION AND CONCLUSIONS

Efforts are needed to increase awareness of the importance of injecting hygiene in preventing SSTI. Interventions to increase swabbing should be included as part of a wider package of injecting hygiene education, particularly in light of associations with receptive and/or distributive syringe sharing.

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.

Testing the Efficacy of Combined Motivational Interviewing and Cognitive Behavioral Skills Training to Reduce Methamphetamine Use and Improve HIV Medication Adherence Among HIV-Positive Gay and Bisexual Men

Prior research has identified subgroups of HIV-positive gay and bisexual men (GBM) based upon information, motivation, and behavioral skills (IMB) profiles related to HIV medication adherence and methamphetamine use. We conducted a randomized controlled trial of a combined motivational interview (MI) and cognitive behavioral therapy (CBT) intervention tailored specifically to the unique context of HIV-positive GBM, and tested whether IMB profiles moderated treatment effects. HIV-positive GBM (N = 210) were randomized to MI + CBT or an attention-matched education control. Both conditions resulted in reduced methamphetamine use, improved medication adherence (and higher CD4 and lower viral loads), and fewer acts of condomless anal sex at 3, 6, 9 and 12 months post-intervention. Furthermore, the MI + CBT condition achieved greater improvements in medication adherence for men who had greater barriers to change compared to similarly-classified men in the control condition, suggesting the importance of pre-intervention profiles for tailoring future interventions.

When "Chems" Meet Sex: A Rising Phenomenon Called "ChemSex"

Background:

The term “chemsex” was coined to indicate the voluntary intake of psychoactive and non psychoactive drugs in the context of recreational settings to facilitate and/or to enhance sexual intercourses mostly among men who have sex with other men (MSM).

Objective:

The authors aimed to review the mechanisms of action, the toxicity and the pattern of use and abuse of substances involved in “chemsex” practice together with the sociocultural background underlying it and the health-related consequences that they may have.

Results:

Gamma-hydroxybutyrate, gamma-butyrolactone,1,4-butanediol, mephedrone, methamphetamine, sildenafil, tadalafil, vardenafil and alkyl nitrites have been described in their role of “chemsex drugs” including pharmacological action and in their implication to impair capacities to chose sexual partners and consensual sex. Moreover, it has been demonstrated that sexual activity over protracted length of time under the influence of chemsex drugs can result in rectal trauma or penile abrasions and a significant increase of the risk of transmission of sexual transmitted diseases, especially in case of condomless intercourses, which are frequent in this context, representing therefore a serious health threat.

Conclusion:

One of the major problems to establish health policy priority interventions for chemsex is the lack of available epidemiological data on the issue. Finally, social actions should be taken in order to break down the barriers that currently exist among chemsex drug users in accessing services, including the shame and stigma often associated with drug use. In conclusion, more specific resources to face high risks of infections and HIV transmission are required in bisexual and homosexual individuals having SUID: sex under the influence of drugs.

Transgenic mice expressing HIV-1 envelope protein gp120 in the brain as an animal model in neuroAIDS research

HIV-1 infection causes injury to the central nervous system (CNS) and is often associated with neurocognitive disorders. One model for brain damage seen in AIDS patients is the transgenic (tg) mouse expressing a soluble envelope protein gp120 of HIV-1 LAV in the brain in astrocytes under the control of the promoter of glial fibrillary acidic protein. These GFAP-gp120tg mice manifest several key neuropathological features observed in AIDS brains, such as decreased synaptic and dendritic density, increased numbers of activated microglia, and pronounced astrocytosis. Several recent studies show that brains of GFAP-gp120tg mice and neurocognitively impaired HIV patients share also a significant number of differentially regulated genes, activation of innate immunity and other cellular signaling pathways, disturbed neurogenesis, and learning deficits. These findings support the continued relevance of the GFAP-gp120tg mouse as a useful model to investigate neurodegenerative mechanisms and develop therapeutic strategies to mitigate the consequences associated with HIV infection of the CNS, neuroAIDS, and HAND.

Methamphetamine potentiates HIV-1gp120-induced microglial neurotoxic activity by enhancing microglial outward K+ current

Methamphetamine (Meth) abuse not only increases the risk of human immunodeficiency virus-1 (HIV-1) infection, but exacerbates HIV-1-associated neurocognitive disorders (HAND) as well. The mechanisms underlying the co-morbid effect are not fully understood. Meth and HIV-1 each alone interacts with microglia and microglia express voltage-gated potassium (K_V) channel K_V1.3. To understand whether K_V1.3 functions an intersecting point for Meth and HIV-1, we studied the augment effect of Meth on HIV-1 glycoprotein 120 (gp120)-induced neurotoxic activity in cultured rat microglial cells. While Meth and gp120 each alone at low (subtoxic) concentrations failed to trigger microglial neurotoxic activity, Meth potentiated gp120-induced microglial neurotoxicity when applied in combination. Meth enhances gp120 effect on microglia by enhancing microglial K_V1.3 protein expression and K_V1.3 current, leading to an increase of neurotoxin production and resultant neuronal injury. Pretreatment of microglia with a specific K_V1.3 antagonist 5-(4-Phenoxybutoxy)psoralen (PAP) or a broad spectrum K_V channel blocker 4-aminopyridine (4-AP) significantly attenuated Meth/gp120-treated microglial production of neurotoxins and resultant neuronal injury, indicating an involvement of K_V1.3 in Meth/gp120-induced microglial neurotoxic activity. Meth/gp120 activated caspase-3 and increased caspase-3/7 activity in microglia and inhibition of caspase-3 by its specific inhibitor significantly decreased microglial production of TNF-α and iNOS and attenuated microglia-associated neurotoxic activity. Moreover, blockage of K_V1.3 by specific blockers attenuated Meth/gp120 enhancement of caspase-3/7 activity. Taking together, these results suggest an involvement of microglial K_V1.3 in the mediation of Meth/gp120 co-morbid effect on microglial neurotoxic activity via caspase-3 signaling.

Neuronal Stress and Injury Caused by HIV-1, cART and Drug Abuse: Converging Contributions to HAND

Multiple mechanisms appear to contribute to neuronal stress and injury underlying HIV-associated neurocognitive disorders (HAND), which occur despite the successful introduction of combination antiretroviral therapy (cART). Evidence is accumulating that components of cART can itself be neurotoxic upon long-term exposure. In addition, abuse of psychostimulants, such as methamphetamine (METH), seems to compromise antiretroviral therapy and aggravate HAND. However, the combined effect of virus and recreational and therapeutic drugs on the brain is still incompletely understood. However, several lines of evidence suggest a shared critical role of oxidative stress, compromised neuronal energy homeostasis and autophagy in promotion and prevention of neuronal dysfunction associated with HIV-1 infection, cART and psychostimulant use. In this review, we present a synopsis of recent work related to neuronal stress and injury induced by HIV infection, antiretrovirals (ARVs) and the highly addictive psychostimulant METH.

Reducing HIV Infections at Circuit Parties: From Description to Explanation and Principles of Intervention Design

Circuit parties are weekend-long, erotically charged, drug-prevalent dance events attended by up to 25 000 self-identified gay and bisexual men who socialize and dance nonstop, sometimes for 24 hours or longer. Although these parties started originally as part of the gay community’s response to raise HIV/AIDS awareness and to build community and cultural identity, they may have become a site for transmitting HIV across geographical regions and socioeconomic groups of gay and bisexual men. This article reviews the descriptive published studies on circuit parties. The authors use these studies and the literature on drug use and high-risk sexual behavior in gay and bisexual communities, along with sociological and social psychological research, to propose a causal model of why circuit parties may contribute to unsafe sexual practices that increase HIV infection risk. The authors abstract 5 prevention messages relevant to circuit parties and review intervention studies in nonparty settings for insight into how to reduce risky sexual behavior within circuit events. These intervention studies help to identify 5 context-specific groups that can effectively carry the prevention messages. The 5-by-5 matrix represents a first stage in developing a causal model for reducing HIV infections, along with evaluable principles of intervention, at circuit parties.

Drug-Drug Interactions and HIV Therapy: What Should Pharmacists Know?

Drug-interaction issues continue to present a major dilemma for the clinician caring for complex patients such as those infected with HIV. The inherent possibility of a drug interaction is magnified by the multitude of drugs being administered in highly-active antiretroviral therapy (HAART). In addition, other classes of medications are used to alleviate side effects, reduce toxicities associated with HAART, or treat concomitant diseases. The modification of one drug by another substance or drug-drug interaction is the main focus of this article. Drug-drug interactions may result in toxicity, treatment failure, or loss of effectiveness and can significantly affect a patient’s clinical outcome. An understanding of the fundamental mechanisms of HIV drug-drug interactions may allow for the early detection or avoidance of troublesome regimens and prudent management if they develop. Although HIV drug interactions are usually thought of as detrimental, resulting in a loss of therapeutic effect or toxicity, some drug interactions such as ritonavir boosted protease inhibitor–based antiretroviral treatments are beneficial and are commonly used in clinical practice. Therefore, pharmacists need to understand drug interaction mechanisms, remember key drug interactions, and vigilantly monitor patients for potential complications.

The effects of D3R on TLR4 signaling involved in the regulation of METH-mediated mast cells activation

Accumulating studies have revealed that the dopamine D3 receptor (D3R) plays an important role in methamphetamine (METH) addiction. However, the action of D3R on METH-mediated immune response and the underlying mechanism remain unclear. Mast cells (MCs) are currently identified as effector cells in many processes of immune responses, and MC activation is induced by various stimuli such as lipopolysaccharide (LPS). Moreover, CD117 and FcεRI are known as MC markers due to their specific expression in MCs. To investigate the effects of D3R on METH-mediated alteration of LPS-induced MCs activation and the underlying mechanism, in this study, we examined the expression of CD117 and FcεRI in the intestines of wild-type (D3R(+/+)) and D3R-deficient (D3R(-/-)) mice. We also measured the production of MC-derived cytokines, including TNF-α, IL-6, IL-4, IL-13 and CCL-5, in the bone marrow-derived mast cells (BMMCs) of WT and D3R(-/-) mice. Furthermore, we explored the effects of D3R on METH-mediated TLR4 and downstream MAPK and NF-κB signaling induced by LPS in mouse BMMCs. We found that METH suppressed MC activation induced by LPS in the intestines of D3R(+/)mice. In contrast, LPS-induced MC activation was less affected by METH in D3R(-/-) mice. Furthermore, METH altered LPS-induced cytokine production in BMMCs of D3R(+/+) mice but not D3R(-/-) mice. D3R was also involved in METH-mediated modulation of LPS-induced expression of TLR4 and downstream MAPK and NF-κB signaling molecules in mouse BMMCs. Taken together, our findings demonstrate that the effect of D3R on TLR4 signaling may be implicated in the regulation of METH-mediated MCs activation induced by LPS.

Non-monosexual Partnerships: Information, Motivation and Self-Efficacy among Methamphetamine-Using Men Who Have Sex with Men Who Also Have Sex with Women or Transgender Persons

OBJECTIVES

Sex with more than one gender is associated with higher substance use, and sexual HIV risk.

METHODS

We examined knowledge, motivation, and self-efficacy to engage in safer substance use and sexual behavior among methamphetamine-using U.S. men who have sex with more than one gender (N=343).

RESULTS

Almost half(46.2%) of the men reported having sex with a man and a woman or transgender partner in the last 30 days. Compared to monosexual MSM, non-monosexual MSM reported greater condom use self-efficacy however, they reported more sexual partners who inject drugs.

CONCLUSION

We observed distinct differences between men who do or do not have sex with more than one gender.

The Effect of Chronic Methamphetamine Exposure on the Hippocampal and Olfactory Bulb Neuroproteomes of Rats

Nowadays, drug abuse and addiction are serious public health problems in the USA. Methamphetamine (METH) is one of the most abused drugs and is known to cause brain damage after repeated exposure. In this paper, we conducted a neuroproteomic study to evaluate METH-induced brain protein dynamics, following a two-week chronic regimen of an escalating dose of METH exposure. Proteins were extracted from rat brain hippocampal and olfactory bulb tissues and subjected to liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Both shotgun and targeted proteomic analysis were performed. Protein quantification was initially based on comparing the spectral counts between METH exposed animals and their control counterparts. Quantitative differences were further confirmed through multiple reaction monitoring (MRM) LC-MS/MS experiments. According to the quantitative results, the expression of 18 proteins (11 in the hippocampus and 7 in the olfactory bulb) underwent a significant alteration as a result of exposing rats to METH. 13 of these proteins were up-regulated after METH exposure while 5 were down-regulated. The altered proteins belonging to different structural and functional families were involved in processes such as cell death, inflammation, oxidation, and apoptosis.

Mitochondrial injury and cognitive function in HIV infection and methamphetamine use

OBJECTIVE

In this work, we evaluated the association of human immunodeficiency virus (HIV) infection and methamphetamine (METH) use with mitochondrial injury in the brain and its implication on neurocognitive impairment.

DESIGN

Mitochondria carry their genome (mtDNA) and play a critical role in cellular processes in the central nervous system. METH is commonly used in HIV-infected populations. HIV infection and METH use can cause damage to mtDNA and lead to neurocognitive morbidity. We evaluated HIV infection and METH use with mitochondrial injury in the brain.

METHODS

We obtained white and gray matter from Brodmann areas 7, 8, 9, 46 of the following: HIV-infected individuals with history of past METH use (HIV+METH+, n = 16), HIV-infected individuals with no history of past METH use (HIV+METH-, n = 11), and HIV-negative controls (HIV-METH-, n = 30). We used the 'common deletion', a 4977 bp mutation, as a measurement of mitochondrial injury, and quantified levels of mtDNA and 'common deletion' by droplet digital PCR, and evaluated in relation to neurocognitive functioning [Global Deficit Score (GDS)].

RESULTS

Levels of mtDNA and mitochondrial injury were highest in white matter of Brodmann area 46. A higher relative proportion of mtDNA carrying the 'common deletion' was associated with lower GDS (P < 0.01) in HIV+METH+ but higher GDS (P < 0.01) in HIV+METH-.

CONCLUSIONS

Increased mitochondrial injury was associated with worse neurocognitive function in HIV+METH- individuals. Among HIV+METH+ individuals, an opposite effect was seen.

Antiretrovirals, Methamphetamine, and HIV-1 Envelope Protein gp120 Compromise Neuronal Energy Homeostasis in Association with Various Degrees of Synaptic and Neuritic Damage

HIV-1 infection frequently causes HIV-associated neurocognitive disorders (HAND) despite combination antiretroviral therapy (cART). Evidence is accumulating that components of cART can themselves be neurotoxic upon long-term exposure. In addition, abuse of psychostimulants, such as methamphetamine, seems to aggravate HAND and compromise antiretroviral therapy. However, the combined effect of virus and recreational and therapeutic drugs on the brain is poorly understood. Therefore, we exposed mixed neuronal-glial cerebrocortical cells to antiretrovirals (ARVs) (zidovudine [AZT], nevirapine [NVP], saquinavir [SQV], and 118-D-24) of four different pharmacological categories and to methamphetamine and, in some experiments, the HIV-1 gp120 protein for 24 h and 7 days. Subsequently, we assessed neuronal injury by fluorescence microscopy, using specific markers for neuronal dendrites and presynaptic terminals. We also analyzed the disturbance of neuronal ATP levels and assessed the involvement of autophagy by using immunofluorescence and Western blotting. ARVs caused alterations of neurites and presynaptic terminals primarily during the 7-day incubation and depending on the specific compounds and their combinations with and without methamphetamine. Similarly, the loss of neuronal ATP was context specific for each of the drugs or combinations thereof, with and without methamphetamine or viral gp120. Loss of ATP was associated with activation of AMP-activated protein kinase (AMPK) and autophagy, which, however, failed to restore normal levels of neuronal ATP. In contrast, boosting autophagy with rapamycin prevented the long-term drop of ATP during exposure to cART in combination with methamphetamine or gp120. Our findings indicate that the overall positive effect of cART on HIV infection is accompanied by detectable neurotoxicity, which in turn may be aggravated by methamphetamine.

Neuropathological sequelae of Human Immunodeficiency Virus and apathy: A review of neuropsychological and neuroimaging studies

Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) despite advances in anti-retroviral treatment (ART). The goal of the current review is to recapitulate findings relating apathy to the deleterious biobehavioral effects of HIV-1 in the post-ART era. Available literatures demonstrate that the emergence of apathy with other neurocognitive and neuropsychiatric symptoms may be attributed to neurotoxic effects of viral proliferation, e.g., aggregative effect of Tat and gp120 on apoptosis, transport and other enzymatic reactions amongst dopaminergic neurons and neuroglia. An assortment of neuroimaging modalities converge on the severity of apathy symptoms associated with the propensity of the virus to replicate within frontal-striatal brain circuits that facilitate emotional processing. Burgeoning research into functional brain connectivity also supports the effects of microvascular and neuro-inflammatory injury linked to aging with HIV-1 on the presentation of neuropsychiatric symptoms. Summarizing these findings, we review domains of HIV-associated neurocognitive and neuropsychiatric impairment linked to apathy in HIV. Taken together, these lines of research suggest that loss of affective, cognitive and behavioral inertia is commensurate with the neuropathology of HIV-1.

Increasing prevalence of HIV infection among first time clients in Italian drug treatment services - is it sexual transmission?

BACKGROUND

Over the last two decades, the proportion of people who inject drugs among newly reported HIV cases in Italy has been continuously declining. This trend is reflected in the prevalence of HIV infection among problem drug users followed in drug treatment services. We report nationwide trends in the prevalence of HIV and HCV among tested clients in charge to drug addiction services from 2005 to 2011.

METHODS

Data on the prevalence of HIV and HCV among drug users from public drug treatment services across Italy were collected and analyzed for the period from 2005 to 2011. Prevalence of HIV and HCV were compared between clients returning to treatment and those entering treatment for the first time, and by gender. Due to the high percentage of missing data, the "inverse probability weight" method was used. Trends in testing uptake were also analysed.

RESULTS

A significant decrease of HIV and HCV prevalence is observed among all PDUs entering treatment (from 14.7% to 11.1% and from 61.6% to 50%, respectively, in 2005-2011). By contrast, among those entering the services for the first time, after an initial decline the prevalence of HIV infection steadily increased in both sexes, from 2.2% in 2009 to 5.3% in 2011. Self-reported injecting rates in this group decreased over time, and in 2011 the proportion reporting drug injecting was lower among new clients than in people returning to services (14.5 vs. 34.4%). We also observed a progressive and significant reduction in HIV and HCV testing in drug treatment services.

CONCLUSIONS

Changes in injection practice and type of drugs used, coupled with a concurrent reduction in HCV prevalence, do not support drug injection as the main explanation for an increased HIV transmission in people entering drug treatment services for the first time. While reductions in testing rates raise concerns over data quality, the possibility of increased sexual transmission needs to be considered.

Club drug use and associated high-risk sexual behaviour in six provinces in China

AIM

To investigate the characteristics of the different club drugs and associated high-risk sexual behaviours in China.

DESIGN

Multicentre cross-sectional study.

SETTING

Drug Detoxification and Rehabilitation Centres in six provinces, China.

PARTICIPANTS

A total of 1434 eligible club drug users were included.

MEASUREMENTS

Participants were investigated by trained interviewers using a self-designed structured questionnaire to collect information on club drug use and associated behaviours.

FINDINGS

Methamphetamine was the most commonly abused drug in participants (73.92%), who used it in their or their friends' homes by non-injection for the purpose of feeling euphoria. Among participants with sexual behaviours after club drug use, 75.21% reported having engaged in sex with multiple partners after club drug use during the past year and 79.84% had unprotected sex after using club drug during the past year. A two-level logistic model showed that male gender [adjusted odds ratio (AOR)=7.14; 95% confidence interval (CI)=4.17-12.5], unmarried (AOR=1.71, 95% CI=1.04-2.79), long duration of club drug use during their life-time (AOR=1.76, 95% CI=1.28-2.42) and severe acute intoxication after using club drugs during the past year (AOR=2.11, 95% CI=1.07-4.15) were independent risk factors of multiple sex partners during the past year. Another two-level model showed that the club drug users who were female (AOR=1.79, 95% CI=1.03-3.11) and had polydrug use during their lifetime (AOR=1.55, 95% CI=1.01-2.34) had more risk for unprotected sex during the past year than without these characteristics.

CONCLUSION

High-risk sexual behaviours are common among club drug users in China. The prevention and intervention of club drug use could decrease the risk of sexual behaviours which further prevent HIV transmission and other sexually transmitted infections in China.

Combination of methamphetamine and HIV-1 gp120 causes distinct long-term alterations of behavior, gene expression, and injury in the central nervous system

Methamphetamine (METH) abuse is frequent in individuals infected with human immunodeficiency virus type-1 (HIV-1) and is suspected to aggravate HIV-associated neurocognitive disorders (HAND). METH is a psychostimulant that compromises several neurotransmitter systems and HIV proteins trigger neuronal injury but the combined effects of viral infection and METH abuse are incompletely understood. In this study we treated transgenic mice expressing the HIV envelope protein gp120 in the brain (HIV-1 gp120tg) at 3-4 months of age with an escalating-dose, multiple-binge METH regimen. The long-term effects were analyzed after 6-7 months of drug abstinence employing behavioral tests and analysis of neuropathology, electrophysiology and gene expression. Behavioral testing showed that both HIV-1 gp120tg and WT animals treated with METH displayed impaired learning and memory. Neuropathological analysis revealed that METH similar to HIV-1 gp120 caused a significant loss of neuronal dendrites and pre-synaptic terminals in hippocampus and cerebral cortex of WT animals. Electrophysiological studies in hippocampal slices showed that METH exposed HIV-1 gp120tg animals displayed reduced post-tetanic potentiation, whereas both gp120 expression and METH lead to reduced long-term potentiation. A quantitative reverse transcription-polymerase chain reaction array showed that gp120 expression, METH and their combination each caused a significant dysregulation of specific components of GABAergic and glutamatergic neurotransmission systems, providing a possible mechanism for synaptic dysfunction and behavioral impairment. In conclusion, both HIV-1 gp120 and METH caused lasting behavioral impairment in association with neuropathology and altered gene expression. However, combined METH exposure and HIV-1 gp120 expression resulted in the most pronounced, long lasting pre- and post-synaptic alterations coinciding with impaired learning and memory.

Human immunodeficiency virus infection heightens concurrent risk of functional dependence in persons with long-term methamphetamine use

OBJECTIVES

Disability among long-term methamphetamine (MA) users is multifactorial. This study examined the additive adverse impact of human immunodeficiency virus (HIV) infection, a common comorbidity in MA users, on functional dependence.

METHODS

A large cohort of participants (N = 798) stratified by lifetime MA-dependence diagnoses (ie, MA+ or MA-) and HIV serostatus (ie, HIV+ or HIV-) underwent comprehensive baseline neuromedical, neuropsychiatric, and functional research evaluations, including assessment of neurocognitive symptoms in daily life, instrumental and basic activities of daily living, and employment status.

RESULTS

Independent, additive effects of MA and HIV were observed across all measures of functional dependence, independent of other demographic, psychiatric, and substance-use factors. The prevalence of global functional dependence increased in the expected stepwise fashion across the cohort, with the lowest rates in the MA-/HIV- group (29%) and the highest rates in the MA+/HIV+ sample (69%). The impact of HIV on MA-associated functional dependence was moderated by nadir CD4 count, such that polysubstance use was associated with greater disability among those HIV-infected persons with higher but not lower nadir CD4 count. Within the MA+/HIV+ cohort, functional dependence was reliably associated with neurocognitive impairment, lower cognitive reserve, polysubstance use, and major depressive disorder.

CONCLUSIONS

HIV infection confers an increased concurrent risk of MA-associated disability, particularly among HIV-infected persons without histories of immune compromise. Directed referrals, earlier HIV treatment, and compensatory strategies aimed at counteracting the effects of low cognitive reserve, neurocognitive impairment, and psychiatric comorbidities on functional dependence in MA+/HIV+ individuals may be warranted.

The multiple truths about crystal meth among young people entrenched in an urban drug scene: a longitudinal ethnographic investigation

Transitions into more harmful forms of illicit drug use among youth have been identified as important foci for research and intervention. In settings around the world, the transition to crystal methamphetamine (meth) use among youth is considered a particularly dangerous and growing problem. Epidemiological evidence suggests that, particularly among young, street-involved populations, meth use is associated with numerous sex- and drug-related "risks behaviors" and negative health outcomes. Relatively few studies, however, have documented how youth themselves understand, experience and script meth use over time. From 2008 to 2012, we conducted over 100 in-depth interviews with 75 street-entrenched youth in Vancouver, Canada, as well as ongoing ethnographic fieldwork, in order to examine youth's understandings and experiences of meth use in the context of an urban drug scene. Our findings revealed positive understandings and experiences of meth in relation to other forms of drug addiction and unaddressed mental health issues. Youth were simultaneously aware of the numerous health-related harms and social costs associated with heavy meth use. Over time, positive understandings of meth may become entirely contradictory to a lived reality in which escalating meth use is a factor in further marginalizing youth, although this may not lead to cessation of use. Recognition of these multiple truths about meth, and the social structural contexts that shape the scripting of meth use among youth in particular settings, may help us to move beyond moralizing debates about how to best educate youth on the "risks" associated with meth, and towards interventions that are congruent with youth's lived experiences and needs across the lifecourse.

Temporal relations between methamphetamine use and HIV seroconversion in gay, bisexual, and other men who have sex with men

Data from a cross-sectional study of gay, bisexual, and other men who have sex with men who were active methamphetamine users were analyzed to assess temporal relations between HIV seroconversion and initiation of methamphetamine use. Of the 100 men, 58 reported being HIV-positive. Most HIV-positive participants (65%) initiated methamphetamine use after seroconverting. Among those who initiated use before seroconversion, 8 years elapsed between onset of use and time of infection. Findings suggest the need to develop nuanced and targeted interventions aimed at disentangling the “meth-sex” link in this population. Findings also suggest use of the drug as a coping mechanism for those living with HIV.

NeuroHIV and use of addictive substances

In the past three decades, substance abuse has been identified as a key comorbidity of human immunodeficiency virus-1 (HIV-1) infection. Many studies have found that the use and abuse of addictive substances hastens the progression of HIV-1 infection and HIV-associated neurocognitive disorders. Advances in highly active antiretroviral therapy (HAART) in the mid-1990s have been successful in limiting the HIV-1 viral load and maintaining a relatively healthy immune response, allowing the life expectancy of patients infected with HIV to approach that of the general population. However, even with HAART, HIV-1 viral proteins are still expressed and eradication of the virus, particularly in the brain, the key reservoir organ, does not occur. In the post-HAART era, the clinical challenge in the treatment of HIV infection is inflammation of the central nervous system (CNS) and its subsequent neurological disorders. To date, various explicit and implicit connections have been identified between the neuronal circuitry involved in immune responses and brain regions affected by and implicated in substance abuse. This chapter discusses past and current medical uses of prototypical substances of abuse, including morphine, alcohol, cocaine, methamphetamine, marijuana, and nicotine, and the evidence that systemic infections, particularly HIV-1 infection, cause neurological dysfunction as a result of inflammation in the CNS, which can increase the risk of substance abuse.

Customizing monoclonal antibodies for the treatment of methamphetamine abuse: current and future applications

Monoclonal antibody-based medications designed to bind (+)-methamphetamine (METH) with high affinity are among the newest approaches to the treatment of METH abuse and the associated medical complications. The potential clinical indications for these medications include treatment of overdose, reduction of drug dependence, and protection of vulnerable populations from METH-related complications. Research designed to discover and conduct preclinical and clinical testing of these antibodies suggests a scientific vision for how intact monoclonal antibody (mAb) (singular and plural) or small antigen-binding fragments of mAb could be engineered to optimize the proteins for specific therapeutic applications. In this review, we discuss keys to success in this development process including choosing predictors of specificity, efficacy, duration of action, and safety of the medications in disease models of acute and chronic drug abuse. We consider important aspects of METH-like hapten design and how hapten structural features influence specificity and affinity, with an example of a high-resolution X-ray crystal structure of a high-affinity antibody to demonstrate this structural relationship. Additionally, several prototype anti-METH mAb forms such as antigen-binding fragments and single-chain variable fragments are under development. Unique, customizable aspects of these fragments are presented with specific possible clinical indications. Finally, we discuss clinical trial progress of the first in kind anti-METH mAb, for which METH is the disease target instead of vulnerable central nervous system networks of receptors, binding sites, and neuronal connections.

Methamphetamine inhibits Toll-like receptor 9-mediated anti-HIV activity in macrophages

Toll-like receptor 9 (TLR9) is one of the key sensors that recognize viral infection/replication in the host cells. Studies have demonstrated that methamphetamine (METH) dysregulated host cell innate immunity and facilitated HIV infection of macrophages. In this study, we present new evidence that METH suppressed TLR9-mediated anti-HIV activity in macrophages. Activation of TLR9 by its agonist CpG-ODN 2216 inhibits HIV replication, which was demonstrated by increased expression of TLR9, interferon (IFN)-α, IFN regulatory factor-7 (IRF-7), myeloid differentiation factor 88 (MyD88), and myxovirus resistance gene A (MxA) in macrophages. However, METH treatment of macrophages greatly compromised the TLR9 signaling-mediated anti-HIV effect and inhibited the expression of TLR9 downstream signaling factors. Dopamine D1 receptor (D1R) antagonists (SCH23390) could block METH-mediated inhibition of anti-HIV activity of TLR9 signaling. Investigation of the underlying mechanisms of the METH action showed that METH treatment selectively down-regulated the expression of TLR9 on macrophages, whereas it had little effect on the expression of other TLRs. Collectively, our results provide further evidence that METH suppresses host cell innate immunity against HIV infection by down-regulating TLR9 expression and its signaling-mediated antiviral effect in macrophages.

Antisocial personality disorder predicts methamphetamine treatment outcomes in homeless, substance-dependent men who have sex with men

One-hundred-thirty-one homeless, substance-dependent MSM were enrolled in a randomized controlled trial to assess the efficacy of a contingency management (CM) intervention for reducing substance use and increasing healthy behavior. Participants were randomized into conditions that either provided additional rewards for substance abstinence and/or health-promoting/prosocial behaviors ("CM-full"; n=64) or for study compliance and attendance only ("CM-lite"; n=67). The purpose of this secondary analysis was to determine the affect of ASPD status on two primary study outcomes: methamphetamine abstinence, and engagement in prosocial/health-promoting behavior. Analyses revealed that individuals with ASPD provided more methamphetamine-negative urine samples (37.5%) than participants without ASPD (30.6%). When controlling for participant sociodemographics and condition assignment, the magnitude of this predicted difference increases to 10% and reached statistical significance (p<.05). On average, participants with ASPD earned fewer vouchers for health-promoting/prosocial behaviors than participants without ASPD ($10.21 [SD=$7.02] versus $18.38 [SD=$13.60]; p<.01). Participants with ASPD displayed superior methamphetamine abstinence outcomes regardless of CM schedule; even with potentially unlimited positive reinforcement, individuals with ASPD displayed suboptimal outcomes in achieving health-promoting/prosocial behaviors.

Influence of methamphetamine on genital herpes simplex virus type 2 infection in a mouse model

BACKGROUND

Use of the stimulant methamphetamine (METH) is increasingly common, with >35 million users worldwide. There is a known association between stimulant use and an increased incidence of HIV and other sexually transmitted infections (STIs). METH is known to have immune modulatory properties. However, the impact of METH on normal immune responses and disease pathogenesis with STIs has not been fully examined.

METHODS

We used a well-characterized murine model to investigate the impact of METH use on genital herpes simplex virus type 2 infection. Plaque assay and quantitative real-time polymerase chain reaction were used to measure viral replication. Cytokine bead array and enzyme-linked immunosorbent assay were used to determine levels of cytokines during host innate immune response.

RESULTS

METH treatment altered behavior, onset of clinical signs, and disease progression. METH-treated mice also had a thinned vaginal epithelium and an increase in virus present in the sensory ganglia. In addition, METH produced a local dysregulation of cytokine secretion that contrasts with its minimal impact on systemic cytokine secretion.

CONCLUSIONS

Results suggest that the METH alterations of the host immune response partially contribute to enhanced genital herpes disease progression. These findings will improve understanding of METH use on host immune responses and susceptibility to disease.

Body mass index, depression and sexual transmission risk behaviors among HIV-positive MSM

Depression has been shown to be a risk factor for serodiscordant unprotected anal intercourse (SDUAI) in some studies, but not others. Body mass index (BMI) has recently been associated with SDUAI; however, to date, no published study has investigated the interactive effect of depression and BMI on SDUAI. The current study assessed the association between depression, BMI, and SDUAI among HIV-positive MSM. Participants were 430 HIV-positive MSM recruited in a Boston community health center where they received primary care. Participants completed audio computer-assisted self interview (ACASI) measures. Objective height and weight and other clinical variables were accessed through participants' electronic medical records. Depression was positively associated with SDUAI. This association was significantly moderated by BMI. Elevated levels of depression were only associated with SDUAI for underweight participants. These findings suggest that underweight, depressed HIV-positive MSM may be particularly likely to engage in SDUAI.

Methamphetamine Modulates Gene Expression Patterns in Monocyte Derived Mature Dendritic Cells

BACKGROUND

The US is currently experiencing a grave epidemic of methamphetamine use as a recreational drug, and the risk for HIV-1 infection attributable to methamphetamine use continues to increase. Recent studies show a high prevalence of HIV infection among methamphetamine users. Dendritic cells (DCs) are potent antigen presenting cells that are the initial line of defense against HIV-1 infection. In addition, DCs also serve as reservoirs for HIV-1 and function at the interface between the adaptive and the innate immune systems, which recognize and internalize pathogens and subsequently activate T cells. Exposure to methamphetamine results in modulation of immune functional parameters that are necessary for host defense. Chronic methamphetamine use can cause psychiatric co-morbidity, neurological complications, and can alter normal biological processes and immune functions. Limited information is available on the mechanisms by which methamphetamine may influence immune function. This study explores the effect of methamphetamine on a specific array of genes that may modulate immune function. We hypothesize that methamphetamine treatment results in the immunomodulation of DC functions, leading to dysregulation of the immune system of the infected host. This suggests that methamphetamine has a role as a cofactor in the pathogenesis of HIV-1.

METHODS

We used the high-throughput technology of gene microarray analysis to understand the molecular mechanisms underlying the genomic changes that alter normal biological processes when DCs are treated with methamphetamine. Additionally, we validated the results obtained from microarray experiments using a combination of quantitative real-time PCR and Western blot analysis.

RESULTS

These data are the first evidence that methamphetamine modulates DC expression of several genes. Methamphetamine treatment alters categories of genes that are associated with chemokine regulation, cytokinesis, signal transduction mechanisms, apoptosis, and cell cycle regulation. This report focuses on a selected group of genes that are significantly modulated by methamphetamine treatment and that have been associated with HIV-1 pathogenesis.

DISCUSSION/CONCLUSION

The purpose of this study was to identify genes that are unique and/or specific to the complex immunomodulatory mechanisms that are altered as a result of methamphetamine abuse in HIV-1-infected patients. These studies will help to identify the molecular mechanisms that underlie methamphetamine toxicity, and several functionally important classes of genes have emerged as targets in methamphetamine-mediated immunopathogenesis of HIV-1. Identification of novel DC-specific and methamphetamine-responsive genes that modulate several biological, molecular, and signal transduction functions may serve as methamphetamine- and/or HIV-1-specific drug targets.

Methamphetamine use, transmission risk behavior and internet use among HIV-infected patients in medical care, San Francisco, 2008

Methamphetamine use is associated with adverse health outcomes and HIV incidence. Few studies have assessed methamphetamine use, sexual behavior and Internet use among HIV-infected patients. Surveys were administered to a sample of HIV-infected patients seeking medical care in a San Francisco county hospital and university-based clinic. In 2008, 35% of homosexual participants, 26% of heterosexual participants and 11% of female participants reported methamphetamine use in the past year. Of participants, 29% reported using the Internet to find sex partners; Internet-users versus non-Internet-users reported a higher median number of sex partners in 6 months (4 vs. 1), were more likely to report unprotected sex (32 vs. 10%), and higher rates of methamphetamine use in the past 12 months (48 vs. 24%). Given the association among methamphetamine use, increased sex partners and Internet use, the Internet may present a new and effective medium for interventions to reduce methamphetamine-associated sexual risk behavior.

Participant characteristics and HIV risk behaviors among individuals entering integrated buprenorphine/naloxone and HIV care

OBJECTIVE

This study was part of a national, multisite demonstration project evaluating the impact of integrated buprenorphine/naloxone treatment and HIV care. The goals of this study were to describe the baseline demographic, clinical, and substance use characteristics of the participants and to explore HIV transmission risk behaviors in this group.

METHODS

Nine sites across the United States participated. Data obtained by interview and chart review included demographic information, medical history, substance use, and risk behaviors.We performed a descriptive analysis of patient characteristics at entry and used logistic regression to evaluate factors associated with 1) unprotected anal or vaginal sex; and 2) needle-sharing within the previous 90 days.

RESULTS

Three hundred eighty-six individuals were included in the study: 303 (78.5%) received buprenorphine/naloxone; 41 (10.6%) received methadone; and 42 (10.9%) received another form of treatment. The analysis of risk behaviors was limited to those in the buprenorphine group (n = 303). Among those reporting vaginal or anal sex in the previous 90 days, 24% had sex without a condom. Factors significantly associated with unprotected sex were: having a partner; female gender; and alcohol use in previous 30 days. A total of 8.9% of participants shared needles in the previous 90 days. Factors significantly associated with needle-sharing were: amphetamine use; marijuana use; homelessness; and anxiety.

CONCLUSIONS

Addressing transmission risk behaviors is an important secondary HIV prevention strategy. In addition to treatment for opioid dependence, addressing other substance use, social issues, particularly housing, and mental health may have important implications for reducing HIV transmission in HIV-infected opioid-dependent patients.

How addictive drugs disrupt presynaptic dopamine neurotransmission

The fundamental principle that unites addictive drugs appears to be that each enhances synaptic dopamine by means that dissociate it from normal behavioral control, so that they act to reinforce their own acquisition. This occurs via the modulation of synaptic mechanisms that can be involved in learning, including enhanced excitation or disinhibition of dopamine neuron activity, blockade of dopamine reuptake, and altering the state of the presynaptic terminal to enhance evoked over basal transmission. Amphetamines offer an exception to such modulation in that they combine multiple effects to produce nonexocytic stimulation-independent release of neurotransmitter via reverse transport independent from normal presynaptic function. Questions about the molecular actions of addictive drugs, prominently including the actions of alcohol and solvents, remain unresolved, but their ability to co-opt normal presynaptic functions helps to explain why treatment for addiction has been challenging.

Effect of methamphetamine on expression of HIV coreceptors and CC-chemokines by dendritic cells

The United States is currently experiencing an entangled epidemic of HIV infection and use of different drugs of abuse, especially of methamphetamine (Meth). Blood monocyte-derived dendritic cells (DC) are the first line of defense against HIV-1 infection, and are the initial target of HIV-1 infection in injection drug users. DC-SIGN present on dendritic cells is the first molecule that facilitates HIV-1 infection independent of CD4 or HIV coreceptors.

AIMS

The aim of this study was to evaluate whether Meth acts as a cofactor in the pathogenesis of HIV-1 infection.

MAIN METHODS

Monocyte derived DCs, obtained from normal subjects were cultured with and without Meth±HIV-1B, followed by analyzing the gene and protein expression by real-time quantitative polymerase chain reaction (RT-PCR) and fluorescence-activated cell-sorting analyses, respectively.

KEY FINDINGS

Our results show that Meth significantly enhances HIV infection, and downregulates the gene expression of chemokines and costimulatory molecules with reciprocal upregulation of HIV coreceptors and DC-SIGN by dendritic cells.

SIGNIFICANCE

Better understanding of the role of Meth in HIV-1 disease susceptibility and the mechanism through which Meth mediates its effects on HIV-1 infection may help to devise novel therapeutic strategies against HIV-1 infection in Meth using HIV-1 infected population.

Neuroimmune pharmacology of neurodegenerative and mental diseases

Neuroimmune pharmacology is a newly emerging field that intersects with neuroscience, immunology, and pharmacology and that is seeking avenues for translational research and better understanding of disease mechanisms. It focuses on the immunity of the central nervous system (CNS) which is greatly influenced by endogenous effectors, such as cytokines and neurotransmitters, and by exogenous substances, including therapeutic compounds, infectious pathogens, and drugs of abuse. In this article, we attempt to raise awareness of the pivotal discovery of how those mediators affect the immunity of the CNS in both physiological conditions and processes of certain mental illnesses, including psychiatric disorders, neurodegenerative diseases, and cerebral dysfunctions due to drugs of abuse. The abnormality in cytokine networks, neurotransmitter homeostasis, and other immune responses may be involved in the neuropathology associated with those mental illnesses, and the therapeutic effects of the potential treatments can be attributed, at least partially, to their immunomodulatory activities. However, the resulting inflammatory cytokines from certain treatments frequently cause psychiatric complications. In addition, the poor neuropathological outcomes frequently found among drug abusers with HIV-1 infection appear to be related to the neurotoxic and immunomodulatory effects of the drugs used. Importantly, glial cells, especially microglia and astrocytes, are key players in the immunomodulatory activities in the CNS, and the functioning CNS is largely dependent upon the reciprocal interactions between neurons and glial cells. Therefore, glia-neuron interactions have become a critical issue for further understanding the disease mechanism. From this review, readers will gain insights into the new field of neuroimmune pharmacology, with a focus on the impacts of CNS immunity on the mental illnesses.

Prevention of HIV infection among injection drug users in resource-limited settings

Injection drug use contributes to considerable global morbidity and mortality associated with human immunodeficiency virus (HIV) infection and AIDS and other infections due to blood-borne pathogens through the direct sharing of needles, syringes, and other injection equipment. Of approximately 16 million injection drug users (IDUs) worldwide, an estimated 3 million are HIV infected. The prevalence of HIV infection among IDUs is high in many countries in Asia and eastern Europe and could exacerbate the HIV epidemic in sub-Saharan Africa. This review summarizes important components of a comprehensive program for prevention of HIV infection in IDUs, including unrestricted legal access to sterile syringes through needle exchange programs and enhanced pharmacy services, treatment for opioid dependence (ie, methadone and buprenorphine treatment), behavioral interventions, and identification and treatment of noninjection drug and alcohol use, which accounts for increased sexual transmission of HIV. Evidence supports the effectiveness of harm-reduction programs over punitive drug-control policies.

An exploration of contextual factors that influence HIV risk in female sex workers in Mexico: The Social Ecological Model applied to HIV risk behaviors

The present study examined the applicability of the Social Ecological Model for explaining condom use in a sample of female sex workers (FSWs) (N=435) participating in a behavioral intervention to increase condom use in Tijuana, Mexico. Using a multigroup path analysis, we compared women who work in bar settings (n=233) to those who worked on the street (n=202) with regard to an individual factor (self-efficacy), an interpersonal factor (client financial incentives), and a structural factor (condom access). Competing models showed differential impacts of these factors in the two venue-based groups. Having access to condoms was associated with greater self-efficacy and less unprotected sex in women who worked in bars. Among street-based FSWs, having clients offer monetary incentives for unprotected sex was related to greater unprotected sex, while having access to condoms was not. Understanding the contextual factors associated with condom use among subgroups of FSWs has important implications for the development of HIV prevention interventions.

Methamphetamine use and malnutrition among street-involved youth

We sought to explore the effect of crystal methamphetamine use on the risk of experiencing malnutrition among street-involved youth in Vancouver, Canada. Risk of malnutrition was defined as being hungry but not having enough money to buy food. Socio-demographic and drug use factors associated with risk of malnutrition were investigated using univariate and multivariate analysis among a prospective cohort of street-involved youth known as the At-Risk Youth Study (ARYS). Between September 2005 and December 2006, 509 street-involved youth were enrolled in ARYS, among whom 21% reported being at risk of malnutrition as defined above in the previous six months. In multivariate analysis, only non-injection crystal methamphetamine was significantly associated with being at risk of malnutrition among this cohort (Adjusted Odds Ratio [AOR] = 1.60, 95% Confidence Interval [CI]: 1.03-2.48, p = 0.036). Interventions seeking to address food insecurity among street youth may benefit from considering drug use patterns since methamphetamine use predicted higher risk in this setting.

Binge use and sex and drug use behaviors among HIV(-), heterosexual methamphetamine users in San Diego

This study identified sociodemographic factors, drug using practices, sexual behaviors, and motivational factors associated with binge (a period of uninterrupted) methamphetamine (MA) use among heterosexual MA users.

SAMPLE AND METHOD

The FASTLANE study provided cross-sectional data collected by audio computer-assisted self-interview (ACASI) between June 2001 and August 2004 from 451 HIV-negative MA users in San Diego, California, USA who had engaged in unprotected sex and used MA in the previous two months.

RESULTS

The study sample was 67.8% male, 49.4% Caucasian, 26.8% African-American, and 12.8% Hispanic with a mean age of 36.6 years; 183 (40.5%) reported binge use in the past 2 months. Compared with non-binge users, binge users of MA were more likely to report risky drug use and sex behaviors and differed in motivations to initiate and currently use MA. The final logistic regression model for binge use included more days of MA use in the last month, ever treated for MA use, injection drug use, higher Beck Depression Inventory score, "experimentation" as a motivation for initiating MA use, and engaging in sex marathons while high on MA. HIV prevention efforts should differentiate and address these differences in motivations for MA use and the associated HIV-risk sex and drug use behaviors as key targets for effective intervention.