Effect of Cannabis Use on Human Immunodeficiency Virus DNA During Suppressive Antiretroviral Therapy

Cannabis Use Associates With Reduced Proviral Burden and Inflammatory Cytokine in Tissues From Men With Clade C HIV-1 on Suppressive Antiretroviral Therapy

BACKGROUND

Human immunodeficiency virus 1 (HIV-1) tissue reservoirs remain the main obstacle against an HIV cure. Limited information exists regarding cannabis's effects on HIV-1 infections in vivo, and the impact of cannabis use on HIV-1 parenchymal tissue reservoirs is unexplored.

METHODS

To investigate whether cannabis use alters HIV-1 tissue reservoirs, we systematically collected 21 postmortem brain and peripheral tissues from 20 men with subtype C HIV-1 and with suppressed viral load enrolled in Zambia, 10 of whom tested positive for cannabis use. The tissue distribution and copies of subtype C HIV-1 LTR, gag, env DNA and RNA, and the relative mRNA levels of cytokines IL-1β, IL-6, IL-10, and TGF-β1 were quantified using PCR-based approaches. Utilizing generalized linear mixed models we compared persons with HIV-1 and suppressed viral load, with and without cannabis use.

RESULTS

The odds of tissues harboring HIV-1 DNA and the viral DNA copies in those tissues were significantly lower in persons using cannabis. Moreover, the transcription levels of proinflammatory cytokines IL-1β and IL-6 in lymphoid tissues of persons using cannabis were also significantly lower.

CONCLUSIONS

Our findings suggested that cannabis use is associated with reduced sizes and inflammatory cytokine expression of subtype C HIV-1 reservoirs in men with suppressed viral load.

Impact of Cannabis Use on Immune Cell Populations and the Viral Reservoir in People With HIV on Suppressive Antiretroviral Therapy

BACKGROUND

Human immunodeficiency virus (HIV) infection remains incurable due to the persistence of a viral reservoir despite antiretroviral therapy (ART). Cannabis (CB) use is prevalent amongst people with HIV (PWH), but the impact of CB on the latent HIV reservoir has not been investigated.

METHODS

Peripheral blood cells from a cohort of PWH who use CB and a matched cohort of PWH who do not use CB on ART were evaluated for expression of maturation/activation markers, HIV-specific T-cell responses, and intact proviral DNA.

RESULTS

CB use was associated with increased abundance of naive T cells, reduced effector T cells, and reduced expression of activation markers. CB use was also associated with reduced levels of exhausted and senescent T cells compared to nonusing controls. HIV-specific T-cell responses were unaffected by CB use. CB use was not associated with intact or total HIV DNA frequency in CD4 T cells.

CONCLUSIONS

This analysis is consistent with the hypothesis that CB use reduces activation, exhaustion, and senescence in the T cells of PWH, and does not impair HIV-specific CD8 T-cell responses. Longitudinal and interventional studies with evaluation of CB exposure are needed to fully evaluate the impact of CB use on the HIV reservoir.

A longitudinal study of cannabis use and risk for cognitive and functional decline among older adults with HIV

Cannabis use is rapidly increasing among older adults in the United States, in part to treat symptoms of common health conditions (e.g., chronic pain, sleep problems). Longitudinal studies of cannabis use and cognitive decline in aging populations living with chronic disease are lacking. We examined different levels of cannabis use and cognitive and everyday function over time among 297 older adults with HIV (ages 50-84 at baseline). Participants were classified based on average cannabis use: frequent (> weekly) (n = 23), occasional (≤ weekly) (n = 83), and non-cannabis users (n=191) and were followed longitudinally for up to 10 years (average years of follow-up = 3.9). Multi-level models examined the effects of average and recent cannabis use on global cognition, global cognitive decline, and functional independence. Occasional cannabis users showed better global cognitive performance overall compared to non-cannabis users. Rates of cognitive decline and functional problems did not vary by average cannabis use. Recent cannabis use was linked to worse cognition at study visits when participants had THC+ urine toxicology-this short-term decrement in cognition was driven by worse memory and did not extend to reports of functional declines. Occasional (≤ weekly) cannabis use was associated with better global cognition over time in older adults with HIV, a group vulnerable to chronic inflammation and cognitive impairment. Recent THC exposure may have a temporary adverse impact on memory. To inform safe and efficacious medical cannabis use, the effects of specific cannabinoid doses on cognition and biological mechanisms must be investigated in older adults.

Changes in Immune-Related Biomarkers and Endocannabinoids as a Function of Frequency of Cannabis Use in People Living With and Without HIV

Background: Cannabis use is common among people living with HIV (PLWH). Some observational studies of PLWH have linked cannabis use to lower immune markers; however, this is yet to be confirmed. In addition, whether HIV affects the endogenous cannabinoid system has not been studied. Our objective was to examine changes in immune-related biomarkers and endocannabinoids as a function of cannabis use frequency in people living with and without HIV. Materials and Methods: Data were obtained from a longitudinal study of men who have sex with men living in Los Angeles with, or at risk for, HIV. By design, half were PLWH. Those eligible for the parent study were willing and able to return for follow-up every 6 months. Those eligible for inclusion in this study reported varying levels of current cannabis use at follow-up. Specifically, one visit corresponded to a period of daily use and another to a period of infrequent use (weekly, monthly, or less than monthly). Banked serum from all eligible participants was analyzed for immune-related biomarkers, endocannabinoids, and paracannabinoids. Results: The analysis included 36 men, 19 of whom were PLWH. PLWH reported greater lifetime methamphetamine or amphetamine use (68% vs. 0%) and current cigarette use (55% vs. 20%) than people without HIV. Serum levels of HIV-related immune biomarkers including tumor necrosis factor receptor 2 (TNFR2; p=0.013) and CD27 (p=0.004) were greater in PLWH, alongside lower anandamide (AEA) (F1,34=5.337, p=0.027) and oleoylethanolamide (OEA) (F1,34=8.222, p=0.007) levels relative to people without HIV. Frequency of cannabis use did not impact the serum analytes in our study. Conclusions: Higher levels of TNFR2 and CD27 and lower levels of AEA and OEA in PLWH underscore the role of the TNF/TNFR superfamily in HIV, while highlighting a new role for the enzymatic activity of fatty acid amide hydrolase (the enzyme that hydrolyzes AEA and OEA) in HIV. Findings that cannabis frequency did not impact the immune phenotype may not generalize to other populations of PLWH. Additional work is required to further clarify the relationship between immune markers and endocannabinoids as a function of cannabis use frequency in PLWH. ClinicalTrials.gov ID: NCT01201083.

The impact of cannabinoids on inflammasome signaling in HIV-1 infection

Human immunodeficiency virus type 1 (HIV-1) is a chronic disease that afflicts over 38 million people worldwide without a known cure. The advent of effective antiretroviral therapies (ART) has significantly decreased the morbidity and mortality associated with HIV-1 infection in people living with HIV-1 (PWH), thanks to durable virologic suppression. Despite this, people with HIV-1 experience chronic inflammation associated with co-morbidities. While no single known mechanism accounts for chronic inflammation, there is significant evidence to support the role of the NLRP3 inflammasome as a key driver. Numerous studies have demonstrated therapeutic impact of cannabinoids, including exerting modulatory effects on the NLRP3 inflammasome. Given the high rates of cannabinoid use in PWH, it is of great interest to understand the intersecting biology of the role of cannabinoids in HIV-1-associated inflammasome signaling. Here we describe the literature of chronic inflammation in people with HIV, the therapeutic impact of cannabinoids in PWH, endocannabinoids in inflammation, and HIV-1-associated inflammation. We describe a key interaction between cannabinoids, the NLRP3 inflammasome, and HIV-1 viral infection, which supports further investigation of the critical role of cannabinoids in HIV-1 infection and inflammasome signaling.

Role of the gut-brain axis in HIV and drug abuse-mediated neuroinflammation

Drug abuse and related disorders are a global public health crisis affecting millions, but to date, limited treatment options are available. Abused drugs include but are not limited to opioids, cocaine, nicotine, methamphetamine, and alcohol. Drug abuse and human immunodeficiency virus-1/acquired immune deficiency syndrome (HIV-1/AIDS) are inextricably linked. Extensive research has been done to understand the effect of prolonged drug use on neuronal signaling networks and gut microbiota. Recently, there has been rising interest in exploring the interactions between the central nervous system and the gut microbiome. This review summarizes the existing research that points toward the potential role of the gut microbiome in the pathogenesis of HIV-1-linked drug abuse and subsequent neuroinflammation and neurodegenerative disorders. Preclinical data about gut dysbiosis as a consequence of drug abuse in the context of HIV-1 has been discussed in detail, along with its implications in various neurodegenerative disorders. Understanding this interplay will help elucidate the etiology and progression of drug abuse-induced neurodegenerative disorders. This will consequently be beneficial in developing possible interventions and therapeutic options for these drug abuse-related disorders.

Tobacco, alcohol, cannabis, and illicit drug use and their association with CD4/CD8 cell count ratio in people with controlled HIV: a cross-sectional study (ANRS CO3 AQUIVIH-NA-QuAliV)

BACKGROUND

To evaluate drug use (alcohol, tobacco, cannabis and other drugs) and its association with mean CD4/CD8 T cell count ratio, a marker of chronic inflammation, in virally suppressed people living with HIV-1 (PLWH) in Nouvelle Aquitaine, France.

METHODS

A multi-centric, cross-sectional analysis was conducted in 2018-19 in the QuAliV study-ANRS CO3 AQUIVIH-NA cohort. Tobacco, alcohol, cannabis, and other drug use (poppers, cocaine, amphetamines, synthetic cathinones, GHB/GBL) were self-reported. CD4 and CD8 T cell counts and viral load measures, ± 2 years of self-report, and other characteristics were abstracted from medical records. Univariable and multivariable linear regression models, adjusted for age, sex, HIV risk group, time since HIV diagnosis, and other drug use were fit for each drug and most recent CD4/CD8 ratio.

RESULTS

660 PLWH, aged 54.7 ± 11.2, were included. 47.7% [315/660] had a CD4/CD8 ratio of < 1. Their mean CD4/CD8 ratio was 1.1 ± 0.6. 35% smoked; ~ 40% were considered to be hazardous drinkers or have alcohol use disorder; 19.9% used cannabis and 11.9% other drugs. Chemsex-associated drug users' CD4/CD8 ratio was on average 0.226 (95% confidence interval [95% CI] - 0.383, - 0.070) lower than that of non-users in univariable analysis (p = 0.005) and 0.165 lower [95% CI - 0.343, 0.012] in multivariable analysis (p = 0.068).

CONCLUSIONS

Mean differences in CD4/CD8 ratio were not significantly different in tobacco, alcohol and cannabis users compared to non-users. However, Chemsex-associated drug users may represent a population at risk of chronic inflammation, the specific determinants of which merit further investigation.

TRIAL REGISTRATION NUMBER

NCT03296202.

Psychoactive Substance Use Disorder in HIV-Infected Adolescents in Botswana: A Comparison Between the Congenitally Infected and Behaviorally Infected Adolescents

Substance use is a major obstacle to preventing and managing HIV among adolescents, who account for 30% of new infections in many parts of the world, including Botswana. Unfortunately, there is a paucity of data on adolescent substance use, especially in the region. Therefore, this study aimed to determine the pattern of psychoactive substance use in adolescents living with HIV (ALWHIV). It also aimed to compare and explore the pattern of substance use disorders and associated factors between congenitally infected adolescents (CIAs) and behaviorally infected adolescents (BIAs). Six hundred and thirty-four ALWHIV were interviewed using a sociodemographic questionnaire, the WHO drug questionnaire, and DSM-5 criteria for substance use disorder. The participants' mean age (SD) was 17.69 (1.6) years, with a male predominance (n = 336, 53%), and the majority (n = 411, 64.8%) were CIAs. Alcohol was the most used substance among the participants, with 15.8% admitting to its current use. The BIAs were more likely to have SUD (χ² = 17.2, P < .01), use more than one substance (χ² = 20.3, P < .01), and more likely to use all psychoactive substances except for inhalants. In the CIAs, regular participation in religious activities was negatively associated with SUD (AOR = 0.36; 95% CI: 0.17-0.77), while struggling with HIV status acceptance was positively associated with SUD (AOR = 2.54; 95% CI: 1.15-5.61) in the BIAs. This study showed a huge burden and similar pattern of substance use disorders among the ALWHIV in Botswana, as reported elsewhere. It also identified the dissimilarities between the BIAs and CIAs regarding substance-related issues and suggested the need for differentiated care.

Cannabis Use Is Associated With Decreased Antiretroviral Therapy Adherence Among Older Adults With HIV

Background

Conflicting evidence exists on the impact of cannabis use on antiretroviral therapy (ART) adherence among people with human immunodeficiency virus (PWH). We leveraged data collected among older PWH to characterize longitudinal associations between cannabis use and ART adherence.

Methods

AIDS Clinical Trials Group (ACTG) A5322 study participants were categorized as <100% (≥1 missed dose in past 7 days) or 100% (no missed doses) ART adherent. Participants self-reported current (past month), intermittent (past year but not past month), and no cannabis (in past year) use at each study visit. Generalized linear models using generalized estimating equations were fit and inverse probability weighting was used to adjust for time-varying confounders and loss to follow-up.

Results

Among 1011 participants (median age, 51 years), 18% reported current, 6% intermittent, and 76% no cannabis use at baseline; 88% reported 100% ART adherence. Current cannabis users were more likely to be <100% adherent than nonusers (adjusted risk ratio [aRR], 1.53 [95% CI, 1.11-2.10]). There was no association between ART adherence and current versus intermittent (aRR, 1.39 [95% CI, .85-2.28]) or intermittent versus no cannabis use (aRR, 1.04 [95% CI, .62-1.73]).

Conclusions

Among a cohort of older PWH, current cannabis users had a higher risk of <100% ART adherence compared to nonusers. These findings have important clinical implications as suboptimal ART adherence is associated with ART drug resistance, virologic failure, and elevated risk for mortality. Further research is needed to elucidate the mechanisms by which cannabis use decreases ART adherence in older PWH and to advance the development of more efficacious methods to mitigate nonadherence in this vulnerable population.

Drugs of Abuse and Their Impact on Viral Pathogenesis

Commonly misused substances such as alcohol, cocaine, heroin, methamphetamine, and opioids suppress immune responses and may impact viral pathogenesis. In recent years, illicit use of opioids has fueled outbreaks of several viral pathogens, including the human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). This review focuses on the myriad of mechanisms by which drugs of abuse impact viral replication and disease progression. Virus–drug interactions can accelerate viral disease progression and lead to increased risk of virus transmission.

Cannabis and Inflammation in HIV: A Review of Human and Animal Studies

Persistent inflammation occurs in people with HIV (PWH) and has many downstream adverse effects including myocardial infarction, neurocognitive impairment and death. Because the proportion of people with HIV who use cannabis is high and cannabis may be anti-inflammatory, it is important to characterize the impact of cannabis use on inflammation specifically in PWH. We performed a selective, non-exhaustive review of the literature on the effects of cannabis on inflammation in PWH. Research in this area suggests that cannabinoids are anti-inflammatory in the setting of HIV. Anti-inflammatory actions are mediated in many cases through effects on the endocannabinoid system (ECS) in the gut, and through stabilization of gut–blood barrier integrity. Cannabidiol may be particularly important as an anti-inflammatory cannabinoid. Cannabis may provide a beneficial intervention to reduce morbidity related to inflammation in PWH.

Confound, Cause, or Cure: The Effect of Cannabinoids on HIV-Associated Neurological Sequelae

The persistence of human immunodeficiency virus-1 (HIV)-associated neurocognitive disorders (HAND) in the era of effective antiretroviral therapy suggests that modern HIV neuropathogenesis is driven, at least in part, by mechanisms distinct from the viral life cycle. Identifying more subtle mechanisms is complicated by frequent comorbidities in HIV⁺ populations. One of the common confounds is substance abuse, with cannabis being the most frequently used psychoactive substance among people living with HIV. The psychoactive effects of cannabis use can themselves mimic, and perhaps magnify, the cognitive deficits observed in HAND; however, the neuromodulatory and anti-inflammatory properties of cannabinoids may counter HIV-induced excitotoxicity and neuroinflammation. Here, we review our understanding of the cross talk between HIV and cannabinoids in the central nervous system by exploring both clinical observations and evidence from preclinical in vivo and in vitro models. Additionally, we comment on recent advances in human, multi-cell in vitro systems that allow for more translatable, mechanistic studies of the relationship between cannabinoid pharmacology and this uniquely human virus.

Social Isolation Is Linked to Inflammation in Aging People With HIV and Uninfected Individuals

BACKGROUND

Even in the era of suppressive antiretroviral therapy, people with HIV (PWH) suffer greater exposure to inflammation than their uninfected peers. Although poor social support and social isolation have been linked to systemic inflammation in the general population, it is not known whether this is true also among PWH.

METHODS

People with and without HIV infection were enrolled in a community-based, single-center study. Primary predictors were the Medical Outcomes Study Social Support Survey, and outcomes were a panel of inflammatory biomarkers (ICAM-1, MCP-1, IL-6, IL-8, IP-10, C-reactive protein, D-dimer, VEGF, sCD14, and uPAR) in blood plasma and cerebrospinal fluid (CSF).

RESULTS

PWH had worse positive social support (P = 0.0138) and affectionate support (P = 0.0078) than did HIV- individuals. A factor analysis was used to group the biomarkers into related categories separately for each fluid. Levels of 3 of the 4 plasma factors were significantly higher in PWH than HIV- (ps = 0.007, 0.001, and 0.0005, respectively). Levels of 1 of the 3 CSF factors also were significantly higher in PWH than HIV- (P = 0.0194). In the combined PWH and HIV- cohort, poorer social support was associated with higher levels of a factor in plasma loading on MCP-1, IL-8, and VEGF (P = 0.020) and with a CSF factor loading on MCP-1 and IL-6 (P = 0.006).

CONCLUSION

These results suggest that enhancing social support might be an intervention to reduce inflammation and its associated adverse outcomes among PWH.

Cannabis and the Gut-Brain Axis Communication in HIV Infection

People living with HIV infection (PWH) disclose that cannabis is an effective strategy for alleviating symptoms associated with HIV disease. However, some medical providers feel ill-informed to engage in evidence-based conversations. HIV leads to alterations in the gut microbiome, gut-brain axis signaling, and chronic inflammation. The endocannabinoid system regulates homeostasis of multiple organ systems. When deficient, dysregulation of the gut-brain axis can result in chronic inflammation and neuroinflammation. Cannabis along with the naturally occurring endocannabinoids has antioxidant and anti-inflammatory properties that can support healing and restoration as an adjunctive therapy. The purpose of this literature review is to report the physiologic mechanisms that occur in the pathology of HIV and discuss potential benefits of cannabinoids in supporting health and reducing the negative effects of comorbidities in PWH.

Methamphetamine and Cannabis: A Tale of Two Drugs and their Effects on HIV, Brain, and Behavior

HIV infection and drug use intersect epidemiologically, and their combination can result in complex effects on brain and behavior. The extent to which drugs affect the health of persons with HIV (PWH) depends on many factors including drug characteristics, use patterns, stage of HIV disease and its treatment, comorbid factors, and age. To consider the range of drug effects, we have selected two that are in common use by PWH: methamphetamine and cannabis. We compare the effects of methamphetamine with those of cannabis, to illustrate how substances may potentiate, worsen, or even buffer the effects of HIV on the CNS. Data from human, animal, and ex vivo studies provide insights into how these drugs have differing effects on the persistent inflammatory state that characterizes HIV infection, including effects on viral replication, immune activation, mitochondrial function, gut permeability, blood brain barrier integrity, glia and neuronal signaling. Moving forward, we consider how these mechanistic insights may inform interventions to improve brain outcomes in PWH. This review summarizes literature from clinical and preclinical studies demonstrating the adverse effects of METH, as well as the potentially beneficial effects of cannabis, on the interacting systemic (e.g., gut barrier leakage/microbial translocation, immune activation, inflammation) and CNS-specific (e.g., glial activation/neuroinflammation, neural injury, mitochondrial toxicity/oxidative stress) mechanisms underlying HIV-associated neurocognitive disorders.

Microstructural brain abnormalities in HIV+ individuals with or without chronic marijuana use

OBJECTIVE

Cognitive deficits and microstructural brain abnormalities are well documented in HIV-positive individuals (HIV+). This study evaluated whether chronic marijuana (MJ) use contributes to additional cognitive deficits or brain microstructural abnormalities that may reflect neuroinflammation or neuronal injury in HIV+.

METHOD

Using a 2 × 2 design, 44 HIV+ participants [23 minimal/no MJ users (HIV+), 21 chronic active MJ users (HIV + MJ)] were compared to 46 seronegative participants [24 minimal/no MJ users (SN) and 22 chronic MJ users (SN + MJ)] on neuropsychological performance (7 cognitive domains) and diffusion tensor imaging metrics, using an automated atlas to assess fractional anisotropy (FA), axial (AD), radial (RD), and mean (MD) diffusivities, in 18 cortical and 4 subcortical brain regions.

RESULTS

Compared to SN and regardless of MJ use, the HIV+ group had lower FA and higher diffusivities in multiple white matter and subcortical structures (p < 0.001-0.050), as well as poorer cognition in Fluency (p = 0.039), Attention/Working Memory (p = 0.009), Learning (p = 0.014), and Memory (p = 0.028). Regardless of HIV serostatus, MJ users had lower AD in uncinate fasciculus (p = 0.024) but similar cognition as nonusers. HIV serostatus and MJ use showed an interactive effect on mean diffusivity in the right globus pallidus but not on cognitive function. Furthermore, lower FA in left anterior internal capsule predicted poorer Fluency across all participants and worse Attention/Working Memory in all except SN subjects, while higher diffusivities in several white matter tracts also predicted lower cognitive domain Z-scores. Lastly, MJ users with or without HIV infection showed greater than normal age-dependent FA declines in superior longitudinal fasciculus, external capsule, and globus pallidus.

CONCLUSIONS

Our findings suggest that, except in the globus pallidus, chronic MJ use had no additional negative influence on brain microstructure or neurocognitive deficits in HIV+ individuals. However, lower AD in the uncinate fasciculus of MJ users suggests axonal loss in this white matter tract that connects to cannabinoid receptor rich brain regions that are involved in verbal memory and emotion. Furthermore, the greater than normal age-dependent FA declines in the white matter tracts and globus pallidus in MJ users suggest that older chronic MJ users may eventually have lesser neuronal integrity in these brain regions.

Recent cannabis use in HIV is associated with reduced inflammatory markers in CSF and blood

OBJECTIVE

To determine whether cannabis may reduce HIV-related persistent inflammation, we evaluated the relationship of cannabis use in people with HIV (PWH) to inflammatory cytokines in CSF and blood plasma.

METHODS

We measured a panel of proinflammatory cytokines (interleukin [IL]-16, C-reactive protein [CRP], IL-6, interferon gamma-induced protein [IP]-10, soluble CD14, and soluble tumor necrosis factor receptor type II [sTNFRII]) in CSF and blood plasma in PWH and HIV- individuals who did or did not use cannabis at various levels of exposure. Participants in this observational cohort were recruited from community sources and underwent lumbar puncture and phlebotomy. Cannabis use parameters were characterized by self-report based on a semistructured timeline follow-back interview. Cytokines were measured using commercially available immunoassays. Data were analyzed using factor analysis.

RESULTS

Participants were 35 PWH and 21 HIV- individuals, mean (SD) age 45.4 (14.5) years, 41 cannabis ever users, and 15 never users. PWH and HIV- were not different in recency, cumulative months, grams, or density of cannabis use. A factor analysis using CSF biomarkers yielded a factor loading on CRP, IL-16, and sTNFRII that was significantly associated with recency of cannabis use (more recent use associated with lower factor 1 values, reflecting less inflammation; r = 0.331 [95% CI 0.0175, 0.586]). In particular, more recent cannabis use was related to lower IL-16 levels (r = 0.549 [0.282, 0.737]). Plasma biomarkers yielded a factor loading on sTNFRII and IP-10 that was associated with more recent cannabis use (more recent use related to less inflammation; r = 0.374 [0.0660, 0.617]).

CONCLUSIONS

Recent cannabis use was associated with lower levels of inflammatory biomarkers, both in CSF and blood, but in different patterns. These results are consistent with compartmentalization of immune effects of cannabis. The principal active components of cannabis are highly lipid soluble and sequestered in brain tissue; thus, our findings are consistent with specific anti-neuroinflammatory effects that may benefit HIV neurologic dysfunction.