Methamphetamine Induces the Release of Proadhesive Extracellular Vesicles and Promotes Syncytia Formation: A Potential Role in HIV-1 Neuropathogenesis

Understanding early HIV-1 rebound dynamics following antiretroviral therapy interruption: The importance of effector cell expansion

Most people living with HIV-1 experience rapid viral rebound once antiretroviral therapy is interrupted; however, a small fraction remain in viral remission for an extended duration. Understanding the factors that determine whether viral rebound is likely after treatment interruption can enable the development of optimal treatment regimens and therapeutic interventions to potentially achieve a functional cure for HIV-1. We built upon the theoretical framework proposed by Conway and Perelson to construct dynamic models of virus-immune interactions to study factors that influence viral rebound dynamics. We evaluated these models using viral load data from 24 individuals following antiretroviral therapy interruption. The best-performing model accurately captures the heterogeneity of viral dynamics and highlights the importance of the effector cell expansion rate. Our results show that post-treatment controllers and non-controllers can be distinguished based on the effector cell expansion rate in our models. Furthermore, these results demonstrate the potential of using dynamic models incorporating an effector cell response to understand early viral rebound dynamics post-antiretroviral therapy interruption.

Comprehensive analyses identify potential biomarkers for encephalitis in HIV infection

Human immunodeficiency virus encephalitis (HIVE) is a severe neurological complication after HIV infection. Evidence shows that genetic factors play an important role in HIVE. The aim of the present study was to identify new potential therapeutic targets for HIVE. Differentially expressed gene (DEG), functional annotation and pathway, and protein-protein interaction analyses were performed to identify the hub genes associated with HIVE. Gene co-expression analysis was carried out to confirm the association between the hub genes and HIVE. Finally, the role of the hub genes in HIVE therapy was evaluated by conducting drug-gene interaction analysis. A total of 20 overlapping DEGs closely related to HIVE were identified. Functional annotation and pathway enrichment analysis indicated that the markedly enriched DEG terms included ion transport, type II interferon signaling, and synaptic signaling. Moreover, protein-protein interaction analysis revealed that 10 key HIVE-related genes were hub genes, including SCN8A, CDK5R2, GRM5, SCN2B, IFI44L, STAT1, SLC17A7, ISG15, FGF12, and FGF13. Furthermore, six hub genes were co-expressed with HIVE-associated host genes in human brain tissue. Finally, three hub genes (STAT1, ISG15, and SCN2B) interacted with several inflammation-associated drugs. These findings suggested that SCN8A, CDK5R2, GRM5, SCN2B, IFI44L, STAT1, SLC17A7, ISG15, FGF12, and FGF13 may be new targets for diagnosis and therapy of HIVE.

Harnessing Stem Cell-Derived Extracellular Vesicles for the Regeneration of Degenerative Bone Conditions

Degenerative bone disorders such as intervertebral disc degeneration (IVDD), osteoarthritis (OA), and osteoporosis (OP) pose significant health challenges for aging populations and lack effective treatment options. The field of regenerative medicine holds promise in addressing these disorders, with a focus on utilizing extracellular vesicles (EVs) derived from stem cells as an innovative therapeutic approach. EVs have shown great potential in stimulating biological responses, making them an attractive candidate for rejuvenating degenerative bone disorders. However, a comprehensive review summarizing the current state of this field and providing a clear assessment of EV-based therapies in degenerative bone disorders is currently deficient. In this review, we aim to fill the existing gap by outlining the current knowledge on the role of EVs derived from different types of stem cells, such as mesenchymal stem cells, embryonic stem cells, and induced pluripotent stem cells, in bone regeneration. Furthermore, we discuss the therapeutic potential of EV-based treatments for IVDD, OA, and OP. By substantiating the use of stem cell-derived EVs, we highlight their promising potential as a cell-free strategy to improve degenerative bone disorders.

Astrocytes: Role in pathogenesis and effect of commonly misused drugs in the HIV infected brain

The roles of astrocytes as reservoirs and producers of a subset of viral proteins in the HIV infected brain have been studied extensively as a key to understanding HIV-associated neurocognitive disorders (HAND). However, their comprehensive role in the context of intersecting substance use and neurocircuitry of the reward pathway and HAND has yet to be fully explained. Use of methamphetamines, cocaine, or opioids in the context of HIV infection have been shown to lead to a faster progression of HAND. Glutamatergic, dopaminergic, and GABAergic systems are implicated in the development of HAND-induced cognitive impairments. A thorough review of scientific literature exploring the variety of mechanisms in which these drugs exert their effects on the HIV brain and astrocytes has revealed marked areas of convergence in overexcitation leading to increased drug-seeking behavior, inflammation, apoptosis, and irreversible neurotoxicity. The present review investigates astrocytes, the neural pathways, and mechanisms of drug disruption that ultimately play a larger holistic role in terms of HIV progression and drug use. There are opportunities for future research, therapeutic intervention, and preventive strategies to diminish HAND in the subset population of patients with HIV and substance use disorder.

The interplay among HIV, monocytes/macrophages, and extracellular vesicles: a systematic review

Despite effective antiretroviral therapies, chronic inflammation and spontaneous viral "blips" occur in HIV-infected patients. Given the roles for monocytes/macrophages in HIV pathogenesis and extracellular vesicles in intercellular communication, we performed this systematic review to delineate the triad of HIV, monocytes/macrophages, and extracellular vesicles in the modulation of immune activation and HIV activities. We searched PubMed, Web of Science, and EBSCO databases for published articles, up to 18 August 2022, relevant to this triad. The search identified 11,836 publications, and 36 studies were deemed eligible and included in this systematic review. Data were extracted for the characteristics of HIV, monocytes/macrophages, and extracellular vesicles used for experiments and the immunologic and virologic outcomes in extracellular vesicle recipient cells. Evidence for the effects on outcomes was synthesized by stratifying the characteristics by outcomes. In this triad, monocytes/macrophages were potential producers and recipients of extracellular vesicles, whose cargo repertoires and functionalities were regulated by HIV infection and cellular stimulation. Extracellular vesicles derived from HIV-infected monocytes/macrophages or the biofluid of HIV-infected patients enhanced innate immune activation and HIV dissemination, cellular entry, replication, and latency reactivation in bystander or infected target cells. These extracellular vesicles could be synthesized in the presence of antiretroviral agents and elicit pathogenic effects in a wide range of nontarget cells. At least eight functional types of extracellular vesicles could be classified based on the diverse extracellular vesicle effects, which were linked to specific virus- and/or host-derived cargos. Thus, the monocyte/macrophage-centered multidirectional crosstalk through extracellular vesicles may help sustain persistent immune activation and residual viral activities during suppressed HIV infection.

Substance Use and Adherence to Antiretroviral Therapy among People Living with HIV in the United States

People with HIV (PWH) report substance use at higher rates than HIV-uninfected individuals. The potential negative impact of single and polysubstance use on HIV treatment among diverse samples of PWH is underexplored. PWH were recruited from the Center for Positive Living at the Montefiore Medical Center (Bronx, NY, USA) from May 2017-April 2018 and completed a cross-sectional survey with measures of substance use, antiretroviral therapy (ART) use, and ART adherence. The overall sample included 237 PWH (54.1% Black, 42.2% female, median age 53 years). Approximately half of the sample reported any current substance use with 23.1% reporting single substance use and 21.4% reporting polysubstance use. Polysubstance use was more prevalent among those with current cigarette smoking relative to those with no current smoking and among females relative to males. Alcohol and cannabis were the most commonly reported polysubstance combination; however, a sizeable proportion of PWH reported other two, three, and four-substance groupings. Single and polysubstance use were associated with lower ART adherence. A thorough understanding of substance use patterns and related adherence challenges may aid with targeted public health interventions to improve HIV care cascade goals, including the integration of substance use prevention into HIV treatment and care settings.

Raman spectroscopy based molecular signatures of methamphetamine and HIV induced mitochondrial dysfunction

METH and HIV Tat treatment results in increased oxidative stress which affects cellular metabolism and causes DNA damage in the treated microglia. Both, METH ± HIV Tat impair mitochondrial respiration, leading to dysfunction in bioenergetics and increased ROS in microglial cells. Our data indicate that mitochondrial dysfunction may be key to the METH and/or HIV Tat-induced neuropathology. METH and/or HIV Tat induced changes in the protein, lipid and nucleotide concentration in microglial cells were measured by Raman Spectroscopy, and we speculate that these fundamental molecular-cellular changes in microglial cells contribute to the neuropathology that is associated with METH abuse in HIV patients.