Brief Report: Coordinated Modulation of Circulating miR-21 in HIV, HIV-Associated Pulmonary Arterial Hypertension, and HIV/Hepatitis C Virus Coinfection

An Outlook on the Etiopathogenesis of Pulmonary Hypertension in HIV

Although overall survival rates of patients infected with human immunodeficiency virus (HIV) have been significantly improved by antiretroviral therapy (ART), chronic comorbidities associated with HIV result in a worsening quality of life. Pulmonary arterial hypertension (PAH) is the most prevalent comorbidity associated with HIV infection. Despite low viremia and a non-replicative state maintained by ART, few people develop PAH. Previous data from animal models and human pulmonary microvascular endothelial cells (HPMVECs) suggests a constellation of events occurring during the propagation of HIV-associated PAH (HIV-PAH). However, these studies have not successfully isolated HIV virions, HIV-DNA, protein 24 antigen (p24), or HIV-RNA from the pulmonary endothelial cells (ECs). It provides an insight into an ongoing inflammatory process that could be attributed to viral proteins. Several studies have demonstrated the role of viral proteins on vascular remodeling. A composite of chronic inflammatory changes mediated by cytokines and growth factors along with several inciting risk factors such as Hepatitis C virus (HCV) co-infection, genetic factors, male predominance, illegal drug usage, and duration of HIV infection have led to molecular changes that result in an initial phase of apoptosis followed by the formation of apoptotic resistant hyperproliferative ECs with altered phenotype. This study aims to identify the risk factors and mechanisms behind HIV-PAH pathobiology at the host-pathogen interface at the intracellular level.

Impact of human immunodeficiency virus on pulmonary vascular disease

With the advent of anti-retroviral therapy, non-AIDS-related comorbidities have increased in people living with HIV. Among these comorbidities, pulmonary hypertension (PH) is one of the most common causes of morbidity and mortality. Although chronic HIV-1 infection is independently associated with the development of pulmonary arterial hypertension, PH in people living with HIV may also be the outcome of various co-morbidities commonly observed in these individuals including chronic obstructive pulmonary disease, left heart disease and co-infections. In addition, the association of these co-morbidities and other risk factors, such as illicit drug use, can exacerbate the development of pulmonary vascular disease. This review will focus on these complex interactions contributing to PH development and exacerbation in HIV patients. We also examine the interactions of HIV proteins, including Nef, Tat, and gp120 in the pulmonary vasculature and how these proteins alter the endothelial and smooth muscle function by transforming them into susceptible PH phenotype. The review also discusses the available infectious and non-infectious animal models to study HIV-associated PAH, highlighting the advantages and disadvantages of each model, along with their ability to mimic the clinical manifestations of HIV-PAH.

Small RNA sequencing of extracellular vesicles identifies circulating miRNAs related to inflammation and oxidative stress in HIV patients

Background

Extracellular vesicles (EVs) are nano-sized particles secreted by most cells. EVs carry nucleic acids that hold promise as potential biomarkers in various diseases. Human immunodeficiency virus type 1 (HIV) infects CD4+ T cells and induces immune dysfunction, inflammation, and EV secretion, but little is known about EV small RNA cargo in relation to immune dysregulation in HIV-infected individuals. Here, we characterize small RNA carried by circulating EVs in HIV-positive subjects on antiretroviral therapy (ART) relative to uninfected controls by next-generation RNA sequencing.

Results

Plasma EVs isolated from HIV-positive and HIV-negative subjects in test (n = 24) and validation (n = 16) cohorts were characterized by electron microscopy, nanoparticle tracking analysis, and immunoblotting for exosome markers. EVs were more abundant in plasma from HIV-positive compared to HIV-negative subjects. Small RNA sequencing of plasma EVs in the test cohort identified diverse small RNA species including miRNA, piRNA, snRNA, snoRNA, tRNA, and rRNA, with miRNA being the most abundant. A total of 351 different miRNAs were detected in plasma EVs, with the top 50 miRNAs accounting for 90% of all miRNA reads. miR-26a-5p was the most abundant miRNA, followed by miR-21-5p and miR-148-3p. qRT-PCR analysis showed that six miRNAs (miR-10a-5p, − 21-5p, −27b-3p, − 122-5p, −146a-5p, − 423-5p) were significantly increased in plasma EVs from HIV-positive compared to HIV-negative subjects in the validation cohort. Furthermore, miR-21-5p, −27b-3p, −146a-5p, and − 423-5p correlated positively with metabolite markers of oxidative stress and negatively with anti-inflammatory polyunsaturated fatty acids. Over-representation and pathway enrichment analyses of miRNAs and their target genes predicted functional association with oxidative stress responses, interferon gamma signaling, Toll-like receptor signaling, TGF beta signaling, and Notch signaling.

Conclusions

HIV-positive individuals on ART have increased abundance of circulating EVs carrying diverse small RNAs, with miRNAs being the most abundant. Several miRNAs associated with inflammation and oxidative stress are increased in circulating EVs of HIV-positive individuals, representing potential biomarkers of targetable pathways that contribute to disease pathogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12865-020-00386-5.

MicroRNA Expression Profile in Peripheral Blood Lymphocytes of Sheep Vaccinated with Nigeria 75/1 Peste Des Petits Ruminants Virus

Peste des petits ruminants (PPR) is one of the highly contagious transboundary viral diseases of small ruminants. Host microRNA (miRNA) expression patterns may change in response to virus infection, and it mainly works as a post-transcriptional moderator in gene expression and affects viral pathogenesis and replication. In this study, the change of miRNA expression profile in peripheral blood lymphocyte (PBMC) from sheep inoculated with PPR vaccine virus in vivo as well as primary sheep testicular (ST) cells inoculated with PPR vaccine virus in vitro were determined via deep sequencing technology. In PBMC cells, 373 and 115 differentially expressed miRNAs (DEmiRNAs) were identified 3 days and 5 days post inoculated (dpi), respectively. While, 575 DEmiRNAs were identified when comparing miRNA profiles on 5 dpi with 3 dpi. Some of the DEmiRNAs were found to change significantly via time-course during PPR vaccine virus inoculated. Similarly, in ST cells, 136 DEmiRNAs were identified at 3 dpi in comparison with mock-inoculation. A total of 12 DEmiRNAs were validated by real-time quantitative PCR (RT-qPCR). The oar-miR-150, oar-miR-370-3p and oar-miR-411b-3p were found common differentially expressed in both PPR vaccine virus-inoculated PBMC cells and ST cells. Targets prediction and functional analysis of the DEmiRNAs uncovered mainly gathering in antigen processing and presentation pathways, protein processing in endoplasmic reticulum pathways and cell adhesion molecules pathways. Our study supplies information about the DEmiRNAs in PPR vaccine virus-inoculated PBMC cells and ST cells, and provides clues for further understanding the function of miRNAs in PPR vaccine virus replication.

Expression analysis of lung miRNAs responding to ovine VM virus infection by RNA-seq

BACKGROUND

MicroRNAs (miRNAs) are short endogenous, single-stranded, noncoding small RNA molecules of approximately 22 nucleotides in length. They regulate gene expression posttranscriptionally by silencing mRNA expression, thus orchestrating many physiological processes. The Small Ruminant Lentiviruses (SRLV) group includes the Visna Maedi Virus (VMV) and Caprine Arthritis Encephalitis (CAEV) viruses, which cause a disease in sheep and goats characterized by pneumonia, mastitis, arthritis and encephalitis. Their main target cells are from the monocyte/macrophage lineage. To date, there are no studies on the role of miRNAs in this viral disease.

RESULTS

Using RNA-seq technology and bioinformatics analysis, the expression levels of miRNAs during different clinical stages of infection were studied. A total of 212 miRNAs were identified, of which 46 were conserved sequences in other species but found for the first time in sheep, and 12 were completely novel. Differential expression analysis comparing the uninfected and seropositive groups showed changes in several miRNAs; however, no significant differences were detected between seropositive asymptomatic and diseased sheep. The robust increase in the expression level of oar-miR-21 is consistent with its increased expression in other viral diseases. Furthermore, the target prediction of the dysregulated miRNAs revealed that they control genes involved in proliferation-related signalling pathways, such as the PI3K-Akt, AMPK and ErbB pathways.

CONCLUSIONS

To the best of our knowledge, this is the first study reporting miRNA profiling in sheep in response to SRLV infection. The known functions of oar-miR-21 as a regulator of inflammation and proliferation appear to be a possible cause of the lesions caused in the sheep's lungs. This miRNA could be an indicator for the severity of the lung lesions, or a putative target for therapeutic intervention.

Relevance of microRNA 21 in Different Types of Hypertension

Hypertension (HTN) is a chronic medical condition that commonly affects the aging population worldwide. The prevalence of HTN is increasing in developing countries and is one of the leading causes of death in older individuals. HTN results from a complex interplay of genetic and environmental factors. Besides, HTN can result in various other health complications such as stroke and chronic kidney diseases, if not treated. Although various studies have explained the underlying mechanisms in the pathogenesis of HTN, limited information is available on their biomarkers. MicroRNAs (miRNAs) are RNA molecules that have been recognized as key regulators for HTN. miR-21 is a common microRNA that is has been reported to be significantly upregulated in HTN individuals. Hence, miR-21 can be a potential therapeutic target for HTN. The number of studies related to miR-21 on hypertension is limited. Therefore, the main thrust of this paper is to provide an overview of the current clinical evidence and significance of miR-21 in HTN.

MicroRNA-210, MicroRNA-331, and MicroRNA-7 Are Differentially Regulated in Treated HIV-1-Infected Individuals and Are Associated With Markers of Systemic Inflammation

OBJECTIVE

Inflammation may contribute to an increased risk of cardiovascular disease (CVD) in HIV-1 infection. MicroRNAs (miRNAs) are involved in the regulation of inflammation. In treated HIV-1-infected individuals, we aimed to identify differentially expressed miRNAs with known roles in inflammation and CVD risk and to investigate associations between these and systemic inflammation.

METHODS

In a screening cohort including 14 HIV-1-infected individuals and 9 uninfected controls, microarray profiling was performed using peripheral blood mononuclear cells (PBMCs). Differentially regulated miRNAs previously related to inflammation and CVD were validated using real-time quantitative reverse-transcription polymerase chain reaction in 26 HIV-1-infected individuals and 20 uninfected controls. Validated miRNAs were measured in PBMCs, CD4 and CD8 T cells. Interleukin-6, tumor necrosis factor-alpha, high-sensitivity C-reactive protein, lipopolysaccharide (LPS), cytomegalovirus immunoglobulin G, lipids, and fasting glucose were measured, and associations with validated miRNAs were assessed with multiple linear regression analysis.

RESULTS

Upregulation of miR-210, miR-7, and miR-331 was found in PBMCs from HIV-1-infected individuals when compared with those from uninfected controls (P < 0.005). In contrast, miR-210 and miR-331 were downregulated in CD8 T cells. In multivariate analysis, miR-210 in CD8 T cells was negatively associated with LPS (P = 0.023) and triglycerides (P = 0.003) but positively associated with tumor necrosis factor-alpha (P = 0.004). MiR-7 in PBMC was positively associated with interleukin-6 (P = 0.025) and fasting glucose (P = 0.005), whereas miR-331 was negatively associated with LPS (P = 0.006). In PBMCs from HIV-1-infected individuals with low cytomegalovirus immunoglobulin G, miR-7, miR-29a, miR-221, and miR-222 were downregulated.

CONCLUSION

In 2 independent cohorts, miR-210, miR-7, and miR-331 were differentially regulated in treated HIV-1-infected individuals and associated with markers of systemic inflammation.

Vascular stiffness mechanoactivates YAP/TAZ-dependent glutaminolysis to drive pulmonary hypertension

Dysregulation of vascular stiffness and cellular metabolism occurs early in pulmonary hypertension (PH). However, the mechanisms by which biophysical properties of the vascular extracellular matrix (ECM) relate to metabolic processes important in PH remain undefined. In this work, we examined cultured pulmonary vascular cells and various types of PH-diseased lung tissue and determined that ECM stiffening resulted in mechanoactivation of the transcriptional coactivators YAP and TAZ (WWTR1). YAP/TAZ activation modulated metabolic enzymes, including glutaminase (GLS1), to coordinate glutaminolysis and glycolysis. Glutaminolysis, an anaplerotic pathway, replenished aspartate for anabolic biosynthesis, which was critical for sustaining proliferation and migration within stiff ECM. In vitro, GLS1 inhibition blocked aspartate production and reprogrammed cellular proliferation pathways, while application of aspartate restored proliferation. In the monocrotaline rat model of PH, pharmacologic modulation of pulmonary vascular stiffness and YAP-dependent mechanotransduction altered glutaminolysis, pulmonary vascular proliferation, and manifestations of PH. Additionally, pharmacologic targeting of GLS1 in this model ameliorated disease progression. Notably, evaluation of simian immunodeficiency virus-infected nonhuman primates and HIV-infected subjects revealed a correlation between YAP/TAZ-GLS activation and PH. These results indicate that ECM stiffening sustains vascular cell growth and migration through YAP/TAZ-dependent glutaminolysis and anaplerosis, and thereby link mechanical stimuli to dysregulated vascular metabolism. Furthermore, this study identifies potential metabolic drug targets for therapeutic development in PH.