Blue Monday: Co-occurring Stimulant Use and HIV Persistence Predict Dysregulated Catecholamine Synthesis

A positive affect intervention alters leukocyte DNA methylation in sexual minority men with HIV who use methamphetamine

OBJECTIVE

This epigenomics sub-study embedded within a randomized controlled trial examined whether an evidenced-based behavioral intervention model that decreased stimulant use altered leukocyte DNA methylation (DNAm).

METHODS

Sexual minority men with HIV who use methamphetamine were randomized to a five-session positive affect intervention (n = 32) or an attention-control condition (n = 21), both delivered during three months of contingency management for stimulant abstinence. All participants exhibited sustained HIV virologic control - an HIV viral load less than 40 copies/mL at baseline and six months post-randomization. The Illumina EPIC BeadChip measured leukocyte methylation of cytosine-phosphate-guanosine (CpG) sites mapping onto five a priori candidate genes of interest (i.e., ADRB2, BDNF, FKBP5, NR3C1, OXTR). Functional DNAm pathways and soluble markers of immune dysfunction were secondary outcomes.

RESULTS

Compared to the attention-control condition, the positive affect intervention significantly decreased methylation of CpG sites on genes that regulate β2 adrenergic and oxytocin receptors. There was an inconsistent pattern for the direction of the intervention effects on methylation of CpG sites on genes for glucocorticoid receptors and brain-derived neurotrophic factor. Pathway analyses adjusting for the false discovery rate (padj < 0.05) revealed significant intervention-related alterations in DNAm of Reactome pathways corresponding to neural function as well as dopamine, glutamate, and serotonin release. Positive affect intervention effects on DNAm were accompanied by significant reductions in the self-reported frequency of stimulant use.

CONCLUSIONS

There is an epigenetic signature of an evidence-based behavioral intervention model that reduced stimulant use, which will guide the identification of biomarkers for treatment responses.

A narrative systematic review of associations and temporality between use of methamphetamine, ecstasy/MDMA, or cocaine with anxiety or depressive symptoms

OBJECTIVE

Anxiety and depression are prevalent mental health problems in people who use illicit stimulants. Improved understanding of the temporal relationship between methamphetamine, ecstasy/MDMA, or cocaine use with anxiety or depression informs public health interventions and treatment options for those experiencing this co-occurrence. This narrative systematic review sought to examine associations and temporality between the use of methamphetamine, ecstasy/MDMA, or cocaine, with anxiety or depressive symptoms. Method Systematic searches of 4 electronic databases were conducted up to August 2023. Study eligibility included the measurement of anxiety and/or depressive symptoms, and frequency of illicit stimulant use (methamphetamine, cocaine, or ecstasy/MDMA) at two separate time points, with data analysis of the association between these variables. The Joanna Briggs Critical Appraisal Checklist was utilised to assess quality. Data was extracted, and a narrative synthesis incorporating an eight-criteria framework to assess associations was conducted. Results 4432 studies were screened for eligibility; 11 studies (3 RCTs and 8 prospective cohort studies) were included. Evidence for an association between depressive symptoms and methamphetamine use was demonstrated in six studies, with temporal evidence in three studies supporting methamphetamine use preceding depressive symptoms. Three studies reported an association between cocaine use and depressive symptoms. Evidence for associations with any of the illicit stimulants and anxiety symptoms was lacking.

CONCLUSIONS

There was some evidence to support a case for temporality, particularly for methamphetamine use and depressive symptoms. Investing in longitudinal studies is pivotal to understanding the dynamic and reciprocal relationship between illicit stimulant use and anxiety or depressive symptoms. A limitation of the study was the variation in the measurement and analysis of outcomes.

Overamped: Stimulant Use and HIV Pathogenesis

PURPOSE OF REVIEW

In the era of HIV treatment as prevention (TasP), more clarity is needed regarding whether people with HIV who use stimulants (i.e., methamphetamine, powder cocaine, and crack cocaine) display elevated HIV viral load and greater immune dysregulation.

RECENT FINDINGS

Although rates of viral suppression have improved in the TasP era, stimulant use was independently associated with elevated viral load in 23 of 28 studies included in our review. In the 12 studies examining other HIV disease markers, there was preliminary evidence for stimulant-associated alterations in gut-immune dysfunction and cellular immunity despite effective HIV treatment. Studies generally focused on documenting the direct associations of stimulant use with biomarkers of HIV pathogenesis without placing these in the context of social determinants of health. Stimulant use is a key barrier to optimizing the effectiveness of TasP. Elucidating the microbiome-gut-brain axis pathways whereby stimulants alter neuroimmune functioning could identify viable targets for pharmacotherapies for stimulant use disorders. Examining interpersonal, neighborhood, and structural determinants that could modify the associations of stimulant use with biomarkers of HIV pathogenesis is critical to guiding the development of comprehensive, multi-level interventions.

Depression and HIV: a scoping review in search of neuroimmune biomarkers

People with HIV are at increased risk for depression, though the neurobiological mechanisms underlying this are unclear. In the last decade, there has been a substantial rise in interest in the contribution of (neuro)inflammation to depression, coupled with rapid advancements in the resolution and sensitivity of biomarker assays such as Luminex, single molecular array and newly developed positron emission tomography radioligands. Numerous pre-clinical and clinical studies have recently leveraged these next-generation immunoassays to identify biomarkers that may be associated with HIV and depression (separately), though few studies have explored these biomarkers in co-occurring HIV and depression. Using a systematic search, we detected 33 publications involving a cumulative N = 10 590 participants which tested for associations between depressive symptoms and 55 biomarkers of inflammation and related processes in participants living with HIV. Formal meta-analyses were not possible as statistical reporting in the field was highly variable; future studies must fully report test statistics and effect size estimates. The majority of included studies were carried out in the United States, with samples that were primarily older and primarily men. Substantial further work is necessary to diversify the geographical, age, and sex distribution of samples in the field. This review finds that alterations in concentrations of certain biomarkers of neuroinflammation (interleukin-6, tumour necrosis factor-α, neopterin) may influence the association between HIV and depression. Equally, the chemokines monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) or the metabolic index kynurenine:tryptophan (Kyn:Trp), which have been the focus of several studies, do not appear to be associated with depressive symptoms amongst people living with HIV, as all (MCP-1) or most (IL-8 and Kyn:Trp) available studies of these biomarkers reported non-significant associations. We propose a biomarker-driven hypothesis of the neuroimmunometabolic mechanisms that may precipitate the increased risk of depression among people with HIV. Chronically activated microglia, which trigger key neuroinflammatory cascades shown to be upregulated in people with HIV, may be the central link connecting HIV infection in the central nervous system with depressive symptoms. Findings from this review may inform research design in future studies of HIV-associated depression and enable concerted efforts towards biomarker discovery.

Brief Report: Impact of Methamphetamine Use and Rectal STIs on Systemic and Rectal Mucosal Inflammation

BACKGROUND

Methamphetamine (MA) use is associated with sexual risk behavior as well as systemic and mucosal inflammation, suggesting parallel biological and behavioral mechanisms of HIV transmission among men who have sex with men (MSM) who use MA. Data evaluating the combined biological effects of MA use with concomitant rectal gonococcal and/or chlamydial (GC/CT) infection on inflammation are limited.

SETTING

Secondary analysis of stored rectal and plasma specimens from 100 MSM participating in an NIDA-funded longitudinal cohort in Los Angeles, CA.

METHODS

This cross-sectional analysis evaluated systemic and rectal inflammatory markers under 2 conditions: (1) recent MA use (by urine drug screen) and (2) rectal GC/CT infection. We evaluated 50 participants with recent MA use (25 with and 25 without rectal GC/CT) and 50 MSM without MA use (25 with and 25 without rectal GC/CT). Log-transformed plasma and rectal immune markers were regressed on MA exposure and rectal GC/CT, controlling for HIV status and age.

RESULTS

Median age was 32 (range 19-45) years, and 58% of participants were living with HIV. Plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-8, IL-1ß, and rectal IL-6 were associated with rectal GC/CT and MA use, independent of HIV status. Higher levels of rectal TNF-α, IL-1ß, and IL-17a were associated with rectal GC/CT.

CONCLUSIONS

Systemic and rectal inflammation was positively associated with rectal GC/CT and MA use. Condomless sex in the setting of GC/CT- and MA-induced immune activation may provide a basis for synergistic biobehavioral mechanisms that promote HIV/STI transmission among MSM who use MA.

Through the Looking-Glass: Psychoneuroimmunology and the Microbiome-Gut-Brain Axis in the Modern Antiretroviral Therapy Era

OBJECTIVE

Depression, substance use disorders, and other neuropsychiatric comorbidities are common in people with HIV (PWH), but the underlying mechanisms are not sufficiently understood. HIV-induced damage to the gastrointestinal tract potentiates residual immune dysregulation in PWH receiving effective antiretroviral therapy. However, few studies among PWH have examined the relevance of microbiome-gut-brain axis: bidirectional crosstalk between the gastrointestinal tract, immune system, and central nervous system.

METHODS

A narrative review was conducted to integrate findings from 159 articles relevant to psychoneuroimmunology (PNI) and microbiome-gut-brain axis research in PWH.

RESULTS

Early PNI studies demonstrated that neuroendocrine signaling via the hypothalamic-pituitary-adrenal axis and autonomic nervous system could partially account for the associations of psychological factors with clinical HIV progression. This review highlights the need for PNI studies examining the mechanistic relevance of the gut microbiota for residual immune dysregulation, tryptophan catabolism, and oxytocin release as key biological determinants of neuropsychiatric comorbidities in PWH (i.e., body-to-mind pathways). It also underscores the continued relevance of neuroendocrine signaling via the hypothalamic-pituitary-adrenal axis, autonomic nervous system, and oxytocin release in modifying microbiome-gut-brain axis functioning (i.e., mind-to-body pathways).

CONCLUSIONS

Advancing our understanding of PNI and microbiome-gut-brain axis pathways relevant to depression, substance use disorders, and other neuropsychiatric comorbidities in PWH can guide the development of novel biobehavioral interventions to optimize health outcomes. Recommendations are provided for biobehavioral and neurobehavioral research investigating bidirectional PNI and microbiome-gut-brain axis pathways among PWH in the modern antiretroviral therapy era.

A Syndemic Approach to Explore Factors Associated with Bacterial Vaginosis

Bacterial vaginosis (BV) is the most common genital infection in women and is associated with an increased risk of sexually transmitted infections and HIV. This study uses a syndemic approach to evaluate factors associated with BV. Non-pregnant, HIV-negative, sexually active, cis-gender women aged 18-45 years living in Miami, Florida were recruited from Nov.2018- Jun.2021. Participants completed a sociodemographic and behavioral questionnaire along with gynecological examinations. BV was diagnosed by Amsel criteria and confirmed by a Nugent score ≥ 4. A syndemic score was calculated as the sum of factors associated with BV. The association between syndemic score and BV was assessed using logistic regression. Of 166 women included, 60.2% had BV. Race, ethnicity, education, vaginal sex, recent cannabis use, and reasons for intravaginal practices were included in the syndemic score. Higher odds of BV were found in women with a score of ≥ 3 compared to women with a score of 0/1. A higher syndemic score was associated with increased odds of having BV. Multilevel interventions to decrease BV are needed to decrease women's risk of acquiring HIV.

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.

Tryptophan depletion predicts lower positive affect in sexual minority men living with HIV who use methamphetamine

This longitudinal study with 76 sexual minority men living with HIV who use methamphetamine examined whether dysregulation of essential amino acid precursors for neurotransmitters at baseline predicted positive and negative affect at 15 months. After controlling for covariates including baseline positive affect, a higher baseline kynurenine/tryptophan (K/T) ratio independently predicted lower positive affect at 15 months (β = - 18.31; 95% CI = - 35.35, - 1.27; p = 0.036). Future clinical research should examine whether bio-behavioral interventions targeting tryptophan degradation could optimize treatments for people living with co-occurring HIV and stimulant use disorders.