Do opioids activate latent HIV-1 by down-regulating anti-HIV microRNAs?

Fentanyl enhances HIV infection in vitro

Acquired immunodeficiency syndrome (AIDS) caused by Human immunodeficiency virus type 1 (HIV-1) has a high tendency among illicit drug abusers. Recently, it is reported that abuse of fentanyl, a potent synthetic μ receptor-stimulating opioid, is an independent risk factor for HIV-1 infection. However, the mechanism of action in augmenting HIV-1 infection still remains elusive. In this study, we found that fentanyl enhanced infection of HIV-1 in MT2 cells, primary macrophages and Jurkat C11 cells. Fentanyl up-regulated CXCR4 and CCR5 receptor expression, which facilitated the entry of virion into host cells. In addition, it down-regulated interferon-β (IFN-β) and interferon-stimulated genes (APOBEC3F, APOBEC3G and MxB) expression in MT2 cells. Our findings identify an essential role of fentanyl in the positive regulation of HIV-1 infection via the upregulation of co-receptors (CXCR4/CCR5) and downregulation of IFN-β and ISGs, and it may have an important role in HIV-1 immunopathogenesis.

Micro-Players of Great Significance-Host microRNA Signature in Viral Infections in Humans and Animals

Over time, more and more is becoming known about micro-players of great significance. This is particularly the case for microRNAs (miRNAs; miR), which have been found to participate in the regulation of many physiological and pathological processes in both humans and animals. One such process is viral infection in humans and animals, in which the host miRNAs—alone or in conjunction with the virus—interact on two levels: viruses may regulate the host’s miRNAs to evade its immune system, while the host miRNAs can play anti- or pro-viral roles. The purpose of this comprehensive review is to present the key miRNAs involved in viral infections in humans and animals. We summarize the data in the available literature, indicating that the signature miRNAs in human viral infections mainly include 12 miRNAs (i.e., miR-155, miR-223, miR-146a, miR-122, miR-125b, miR-132, miR-34a, miR -21, miR-16, miR-181 family, let-7 family, and miR-10a), while 10 miRNAs are commonly found in animals (i.e., miR-155, miR-223, miR-146a, miR-145, miR-21, miR-15a/miR-16 cluster, miR-181 family, let-7 family, and miR-122) in this context. Knowledge of which miRNAs are involved in different viral infections and the biological functions that they play can help in understanding the pathogenesis of viral diseases, facilitating the future development of therapeutic agents for both humans and animals.

miR-223: An Immune Regulator in Infectious Disorders

MicroRNAs (miRNAs) are diminutive noncoding RNAs that can influence disease development and progression by post-transcriptionally regulating gene expression. The anti-inflammatory miRNA, miR-223, was first identified as a regulator of myelopoietic differentiation in 2003. This miR-223 exhibits multiple regulatory functions in the immune response, and abnormal expression of miR-223 is shown to be associated with multiple infectious diseases, including viral hepatitis, human immunodeficiency virus type 1 (HIV-1), and tuberculosis (TB) by influencing neutrophil infiltration, macrophage function, dendritic cell (DC) maturation and inflammasome activation. This review summarizes the current understanding of miR-223 physiopathology and highlights the molecular mechanism by which miR-223 regulates immune responses to infectious diseases and how it may be targeted for diagnosis and treatment.

MicroRNA‑28‑3p inhibits angiotensin‑converting enzyme 2 ectodomain shedding in 293T cells treated with the spike protein of severe acute respiratory syndrome coronavirus 2 by targeting A disintegrin and metalloproteinase 17

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus that causes coronavirus disease 2019. Angiotensin-converting enzyme 2 (ACE2) is the SARS-CoV binding site and is ubiquitously expressed in endothelial cells of several organs, with the highest levels in the cardiovascular system, kidney and lungs. A disintegrin and metalloproteinase 17 (ADAM17) is involved in ectodomain shedding of ACE2. In the present study, reverse-transcription-quantitative PCR, transfection, TUNNEL assay, dual-luciferase activity assay and western blotting were conducted to investigate the effects of microRNA (miR)-28-3p on ADAM17-dependent shedding of the ACE2 ectodomain following treatment with the spike protein (S-protein) of SARS-CoV-2. It was found that miR-28-3p was significantly downregulated in 293T cells treated with 100 ng/ml of S-protein for 24 h at 37°C, which led to upregulation of ADAM17. In addition, the expression of ADAM17 and miR-28-3p were negatively correlated based on Pearson's correlation test in 293T cells treated with S-protein for 24 h. Overexpression of miR-28-3p and inhibition of ADAM17 regulated 293T cell viability, apoptosis and ACE2 ectodomain shedding. It was also demonstrated that ADAM17 was the target gene of miR-28-3p and that miR-28-3p negatively regulated ADAM17 expression. Notably, the inhibition of ADAM17 expression blocked the effects of miR-28-3p inhibitor on proliferation, apoptosis and ACE2 ectodomain shedding in 293T cells treated with S-protein. The findings of the present study suggested that miR-28-3p inhibits ADAM17-dependent ACE2 ectodomain shedding in 293T cells treated with the S-protein of SARS-CoV-2, which suggested the potential therapeutic role of miR-28-3p mimic in the prevention and treatment of patients with SARS-CoV-2.

Chronic morphine administration differentially modulates viral reservoirs in SIVmac251 infected rhesus macaque model

HIV persists in cellular reservoirs despite effective combined antiretroviral therapy (cART) and there is viremia flare up upon therapy interruption. Opioids modulate the immune system and suppress antiviral gene responses, which significantly impact people living with HIV (PLWH). However, the effect of opioids on viral reservoir dynamics remain elusive. Herein, we developed a morphine dependent SIVmac251 infected Rhesus macaque (RM) model to study the impact of opioids on HIV reservoirs. RMs on a morphine (or saline control) regimen were infected with SIVmac251. The cART was initiated in approximately half the animals five weeks post-infection, and morphine/saline administration continued until the end of the study. Among the untreated RM, we did not find any difference in plasma/CSF or in cell-associated DNA/RNA viral load in anatomical tissues. On the other hand, within the cART suppressed macaques, there was a reduction in cell-associated DNA load, intact proviral DNA levels, and in inducible SIV reservoir in lymph nodes (LNs) of morphine administered RMs. In distinction to LNs, in the CNS, the size of latent SIV reservoirs was higher in the CD11b+ microglia/macrophages in morphine dependent RMs. These results suggest that in the proposed model, morphine plays a differential role in SIV reservoirs by reducing the CD4+ T-cell reservoir in lymphoid tissues, while increasing the microglia/reservoir size in CNS tissue. The findings from this pre-clinical model will serve as a tool for screening therapeutic strategies to reduce/eliminate HIV reservoirs in opioid dependent PLWH.IMPORTANCE Identification and clearance of HIV reservoirs is a major challenge in achieving a cure for HIV. This is further complicated by co-morbidities that may alter the size of the reservoirs. There is an overlap between the risk factors for HIV and opioid abuse. Opiates have been recognized as prominent co-morbidities in HIV-infected populations. People infected with HIV also abusing opioids have immune modulatory effects and more severe neurological disease. However, the impact of opioid abuse on HIV reservoirs remains unclear. In this study, we used morphine dependent SIVmac251 infected rhesus macaque (RM) model to study the impact of opioids on HIV reservoirs. Our studies suggested that people with HIV who abuse opioids had higher reservoirs in CNS than the lymphoid system. Extrapolating the macaque findings in humans suggests that such differential modulation of HIV reservoirs among people living with HIV abusing opioids could be considered for future HIV cure research efforts.

Persons who inject drugs (PWID) retain functional NK cells, dendritic cell stimulation, and adaptive immune recall responses despite prolonged opioid use

Previous literature suggests that acute opioid use results in the functional impairment of the immune response, thereby decreasing resistance to viral infection. Here, we assessed if innate and adaptive immune responses are compromised ex vivo in persons who inject drugs (PWID) and whether long-term injection drug use may impact host susceptibility to in vitro HIV infection. We measured the frequency, activation state, and functional profile of NK cells, dendritic cells, and CD4+ and CD8+ T cells in low-risk PWID who do not share needles, high-risk needle-sharing PWID, and control donors who did not inject drugs. We also assessed plasma levels of inflammatory markers and CD4+ T cell susceptibility to HIV infection. We observed a significant increase in the amount of sCD14 (P = 0.0023, n = 16) and sCD163 (P = 0.0001, n = 16) in the plasma of PWID compared to controls. Evidence of constitutive activation was noted in PWID as compared to controls with increased CD69 expression in CD56dim NK cells (P = 0.0103, n = 26) and increased CD38 and HLA-DR expression in CD4+ T cells (P = 0.0355, n = 23). However, no innate or adaptive functional differences were detected between PWID and controls, including: NK cell direct or antibody-dependent cellular cytotoxicity poly-functional response, TLR-stimulated dendritic cell/NK crosstalk, CD8+ T cell response to Staphylococcal enterotoxin B or CMV/EBV/FLU peptides, or constitutive or anti-CD3/CD28-stimulated CD4+ T cell infectivity with CCR5-tropic or CXCR4-tropic HIV-1 isolates. Our data indicate that PWID who utilize opioids over as prolonged time frame can retain a functional ex vivo immune response without a measurable increase in CD4+ T cell infectivity suggesting that leukocytes from PWID are not intrinsically more susceptibility to infection with HIV than non-PWID controls.

Effect of Opioid Use on Immune Activation and HIV Persistence on ART

While there is an emerging consensus that engagement of the Mu opioid receptor by opioids may modulate various stages the HIV life cycle (e.g.: increasing cell susceptibility to infection, promoting viral transcription, and depressing immune responses to virally-infected cells), the overall effect on latency and viral reservoirs remains unclear. Importantly, the hypothesis that the increase in immune activation observed in chronic opioid users by direct or indirect mechanisms (i.e., microbial translocation) would lead to a larger HIV reservoir after ART-suppression has not been supported to date. The potential for a subsequent decrease in reservoirs after ART-suppression has been postulated and is supported by early reports of opioid users having lower latent HIV burden. Here, we review experimental data supporting the link between opioid use and HIV modulation, as well as the scientific premise for expecting differential changes in immune activation and HIV reservoir between different medications for opioid use disorder. A better understanding of potential changes in HIV reservoirs relative to the engagement of the Mu opioid receptor and ART-mediated immune reconstitution will help guide future cure-directed studies in persons living with HIV and opioid use disorder. Graphical Abstract Review. HIV replication, immune activation and dysbiosis: opioids may affect immune reconstitution outcomes despite viral suppression.

Opioid and neuroHIV Comorbidity - Current and Future Perspectives

With the current national opioid crisis, it is critical to examine the mechanisms underlying pathophysiologic interactions between human immunodeficiency virus (HIV) and opioids in the central nervous system (CNS). Recent advances in experimental models, methodology, and our understanding of disease processes at the molecular and cellular levels reveal opioid-HIV interactions with increasing clarity. However, despite the substantial new insight, the unique impact of opioids on the severity, progression, and prognosis of neuroHIV and HIV-associated neurocognitive disorders (HAND) are not fully understood. In this review, we explore, in detail, what is currently known about mechanisms underlying opioid interactions with HIV, with emphasis on individual HIV-1-expressed gene products at the molecular, cellular and systems levels. Furthermore, we review preclinical and clinical studies with a focus on key considerations when addressing questions of whether opioid-HIV interactive pathogenesis results in unique structural or functional deficits not seen with either disease alone. These considerations include, understanding the combined consequences of HIV-1 genetic variants, host variants, and μ-opioid receptor (MOR) and HIV chemokine co-receptor interactions on the comorbidity. Lastly, we present topics that need to be considered in the future to better understand the unique contributions of opioids to the pathophysiology of neuroHIV.

Graphical Abstract

Synthetic Opioid Use and Common Injection-associated Viruses: Expanding the Translational Research Agenda

The US is in the midst of a major epidemic of opioid addiction and related comorbidities. People with opioid use disorder (OUD) are at significant risk for transmission of several blood-borne pathogens including the human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Commonly abused opioids and their receptors promote viral replication and virus-mediated pathology. However, most studies demonstrating an adverse effect of drugs of abuse have been conducted in vitro, the specific effects of synthetic opioids on viral replication have been poorly characterized, and the evaluation of opioid-virus interactions in clinically relevant populations is rare. Rigorous characterization of the interactions among synthetic opioids, host cells, and common injection-associated viral infections will require an interdisciplinary research approach and translational studies conducted on humans. Such research promises to improve clinical management paradigms for difficult-to-treat populations, facilitate rational public health policies given severely strained resources, and reveal additional pathways for novel target-specific therapeutic interventions. This mini-review examines the published literature on the effects of opioids on HIV, HBV, and HCV pathogenesis and proposes a series of scientific questions and considerations to establish a translational research agenda focused on opioid-virus interactions.

Opioids and Opioid Maintenance Therapies: Their Impact on Monocyte-Mediated HIV Neuropathogenesis

BACKGROUND

HIV-1 enters the CNS within two weeks after peripheral infection and results in chronic neuroinflammation that leads to HIV associated neurocognitive disorders (HAND) in more than 50% of infected people. HIV enters the CNS by transmigration of infected monocytes across the blood brain barrier. Intravenous drug abuse is a major risk factor for HIV-1 infection, and opioids have been shown to alter the progression and severity of HAND. Methadone and buprenorphine are opioid derivates that are used as opioid maintenance therapies. They are commonly used to treat opioid dependency in HIV infected substance abusers, but their effects on monocyte migration relevant to the development of cognitive impairment are not well characterized.

CONCLUSION

Here, we will discuss the effects of opioids and opioid maintenance therapies on the inflammatory functions of monocytes and macrophages that are related to the development of neuroinflammation in the context of HIV infection.

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.

Opioids and Viral Infections: A Double-Edged Sword

Opioids and their receptors have received remarkable attention because they have the ability to alter immune function, which affects disease progression. In vitro and in vivo findings as well as observations in humans indicate that opioids and their receptors positively or negatively affect viral replication and virus-mediated pathology. The present study reviews recent insights in the role of opioids and their receptors in viral infections and discusses possible therapeutic opportunities. This review supports the emerging concept that opioids and their receptors have both favorable and unfavorable effects on viral disease, depending on the type of virus. Targeting of the opioid system is a potential option for developing effective therapies; however caution is required in relation to the beneficial functions of opioid systems.

Endogenous opiates and behavior: 2012

This paper is the thirty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2012 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).

Diverse functions of miR-125 family in different cell contexts

MicroRNAs (miRNAs) are emerging as a novel class of non-coding RNA molecules that regulate gene expression at a post-transcriptional level. More than 1000 miRNAs have been identified in human cells to date, and they are reported to play important roles in normal cell homeostasis, cell metastasis and disease pathogensis and progression. MiR-125, which is a highly conserved miRNA throughout diverse species from nematode to humans, consists of three homologs hsa-miR-125a, hsa-miR-125b-1 and hsa-miR-125-2. Members of this family have been validated to be down-regulated, exhibiting its disease-suppressing properties in many different types of diseases, while they also have disease-promoting functions in certain contexts. MiR-125 targets a number of genes such as transcription factors, matrix-metalloprotease, members of Bcl-2 family and others, aberrance of which may lead to abnormal proliferation, metastasis and invasion of cells, even carcinomas. Furthermore, miR-125 plays a crucial role in immunological host defense, especially in response to bacterial or viral infections. In this review, we summarize the implication of miR-125 family in disease suppression and promotion, focusing on carcinoma and host immune responses. We also discussed the potential of this miRNA family as promising biomarkers and therapeutic targets for different diseases in future.

Cocaine modulates the expression of opioid receptors and miR-let-7d in zebrafish embryos

Prenatal exposure to cocaine, in mammals, has been shown to interfere with the expression of opioid receptors, which can have repercussions in its activity. Likewise, microRNAs, such as let-7, have been shown to regulate the expression of opioid receptors and hence their functions in mammals and in vitro experiments. In light of this, using the zebrafish embryos as a model our aim here was to evaluate the actions of cocaine in the expression of opioid receptors and let-7d miRNA during embryogenesis. In order to determine the effects produced by cocaine on the opioid receptors (zfmor, zfdor1 and zfdor2) and let-7d miRNA (dre-let-7d) and its precursors (dre-let-7d-1 and dre-let-7d-2), embryos were exposed to 1.5 µM cocaine hydrochloride (HCl). Our results revealed that cocaine upregulated dre-let-7d and its precursors, and also increased the expression of zfmor, zfdor1 and zfdor2 during early developmental stages and decreased them in late embryonic stages. The changes observed in the expression of opioid receptors might occur through dre-let-7d, since DNA sequences and the morpholinos of opioid receptors microinjections altered the expression of dre-let-7d and its precursors. Likewise, opioid receptors and dre-let-7d showed similar distributions in the central nervous system (CNS) and at the periphery, pointing to a possible interrelationship between them.In conclusion, the silencing and overexpression of opioid receptors altered the expression of dre-let-7d, which points to the notion that cocaine via dre-let-7 can modulate the expression of opioid receptors. Our study provides new insights into the actions of cocaine during zebrafish embryogenesis, indicating a role of miRNAs, let-7d, in development and its relationship with gene expression of opioid receptors, related to pain and addiction process.