Systemic and cell-specific mechanisms of vasculopathy induced by human immunodeficiency virus and highly active antiretroviral therapy

People living with HIV display increased anti-apolipoprotein A1 auto-antibodies, inflammation, and kynurenine metabolites: a case-control study

Objective

This study aimed to study the relationship between auto-antibodies against apolipoprotein A1 (anti-apoA1 IgG), human immunodeficiency virus (HIV) infection, anti-retroviral therapy (ART), and the tryptophan pathways in HIV-related cardiovascular disease.

Design

This case-control study conducted in South Africa consisted of control volunteers (n = 50), people living with HIV (PLWH) on ART (n = 50), and untreated PLWH (n = 44). Cardiovascular risk scores were determined, vascular measures were performed, and an extensive biochemical characterisation (routine, metabolomic, and inflammatory systemic profiles) was performed.

Methods

Anti-apoA1 IgG levels were assessed by an in-house ELISA. Inflammatory biomarkers were measured with the Meso Scale Discovery® platform, and kynurenine pathway metabolites were assessed using targeted metabolomic profiling conducted by liquid chromatography-multiple reaction monitoring/mass spectrometry (LC-MRM/MS).

Results

Cardiovascular risk scores and vascular measures exhibited similarities across the three groups, while important differences were observed in systemic inflammatory and tryptophan pathways. Anti-apoA1 IgG seropositivity rates were 15%, 40%, and 70% in control volunteers, PLWH ART-treated, and PLWH ART-naïve, respectively. Circulating anti-apoA1 IgG levels were significantly negatively associated with CD4+ cell counts and positively associated with viremia and pro-inflammatory biomarkers (IFNγ, TNFα, MIPα, ICAM-1, VCAM-1). While circulating anti-apoA1 IgG levels were associated with increased levels of kynurenine in both control volunteers and PLWH, the kynurenine/tryptophan ratio was significantly increased in PLWH ART-treated.

Conclusion

HIV infection increases the humoral response against apoA1, which is associated with established HIV severity criteria and kynurenine pathway activation.

Symptomatic human immunodeficiency virus infection is associated with advanced presentation and perioperative mortality in patients undergoing surgery for peripheral arterial disease

OBJECTIVE

Prior studies have demonstrated an increased risk of developing cardiovascular and peripheral arterial disease (PAD) in patients with human immunodeficiency virus (HIV). However, the effect of chronic HIV infection in patients with preexisting PAD and requiring vascular intervention is unclear. In the present study, we assessed the differences in clinical presentation and perioperative outcomes for patients with PAD who had undergone revascularization or amputation with and without HIV infection.

METHODS

International Classification of Diseases, 9th and 10th Revisions, Clinical Modification, codes were used to identify patients with a prior diagnosis of PAD who had undergone lower extremity revascularization or amputation in the National Inpatient Sample (2003-2017). From this group, the patients were divided for analysis into those with and without HIV infection. Of the patients with HIV infection (PWHs), we identified additional subsets of patients: those with any prior or current diagnosis of an HIV-related illness, including acquired immunodeficiency syndrome, designated as symptomatic HIV, and those without such a diagnosis, designated as asymptomatic HIV infection. Propensity score matching was performed to create matched cohorts. Population-based comparative analyses were performed of the clinical characteristics of the HIV-infected and HIV-uninfected groups. Univariate and multivariate logistic regression analyses of the perioperative in-hospital outcomes were performed on the matched cohorts.

RESULTS

A total of 224,912 patients aged 18 to 85 years were identified who had been admitted with an established diagnosis of PAD and had undergone a lower extremity procedure. Of these patients, 1264 (0.56%) also had a diagnosis of HIV infection. Symptomatic PWHs were more likely to present with critical limb ischemia than were the HIV-uninfected patients or asymptomatic PWHs (66.2% vs 46.3% and 43.6%; P < .01). However, both asymptomatic and symptomatic PWHs were more likely to have required minor (7.5% and 6.7% vs 2.6%; P < .01) and major (12.9% and 27.4% vs 7.0%; P < .01) amputations than were matched HIV-uninfected controls. Although adjusted multivariate logistic regression analysis demonstrated symptomatic HIV infection to be a significant, independent predictor of in-hospital mortality (odds ratio, 2.46; 95% confidence interval, 1.37-4.40; P = .003), the perioperative mortality for the asymptomatic PWH was comparable to that of matched HIV-uninfected controls.

CONCLUSIONS

Symptomatic PWHs, including patients living with acquired immunodeficiency syndrome, who had required a PAD-related procedure had presented with more advanced vascular disease and were most at risk of early perioperative mortality. However, the presentation and mortality between asymptomatic PWHs with well-controlled disease and HIV-uninfected patients were comparable. All PWHs with PAD were more likely to undergo lower extremity amputations than were HIV-uninfected matched controls. Asymptomatic, well-controlled HIV infection should not be a contraindication to elective PAD-related procedures because the mortality was similar to that of HIV-uninfected controls. However, the limb salvage rates might be lower for all PWHs with PAD, regardless of HIV disease severity. Taken together, these findings can improve perioperative risk stratification and surgical management of PAD in this high-risk population.

Atypical antipsychotic drugs deregulate the cholesterol metabolism of macrophage-foam cells by activating NOX-ROS-PPARγ-CD36 signaling pathway

BACKGROUND

Clinical reports indicate that schizophrenia patients taking atypical antipsychotic drugs suffer from metabolism diseases including atherosclerosis. However, the mechanisms underlying the detrimental effect of atypical antipsychotic drugs on atherosclerosis remain to be explored.

METHODS

In this study, we used apolipoprotein E-deficient (apoe^-/-) hyperlipidemic mice and apoe^-/-cd36^-/- mice to investigate the underlying mechanism of atypical antipsychotic drugs on atherosclerosis and macrophage-foam cells.

RESULTS

In vivo studies showed that genetic deletion of cd36 gene ablated the pro-atherogenic effect of olanzapine in apoe^-/- mice. Moreover, in vitro studies revealed that genetic deletion or siRNA-mediated knockdown of cd36 or pharmacological inhibition of CD36 prevented atypical antipsychotic drugs-induced oxLDL accumulation in macrophages. Additionally, olanzapine and clozapine activated NADPH oxidase (NOX) to generate reactive oxygen species (ROS) which upregulated the activity of peroxisome proliferator-activated receptor γ (PPARγ) and subsequently elevated CD36 expression. Inhibition of NOX activity, ROS production or PPARγ activity suppressed CD36 expression and abolished the detrimental effects of olanzapine and clozapine on oxLDL accumulation in macrophages.

CONCLUSION

Collectively, our results suggest that atypical antipsychotic drugs exacerbate atherosclerosis and macrophage-foam cell formation by activating the NOX-ROS-PPARγ-CD36 pathway.

Cerebral Vascular Toxicity of Antiretroviral Therapy

HIV infection is associated with comorbidities that are likely to be driven not only by HIV itself, but also by the toxicity of long-term use of antiretroviral therapy (ART). Indeed, increasing evidence demonstrates that the antiretroviral drugs used for HIV treatment have toxic effects resulting in various cellular and tissue pathologies. The blood-brain barrier (BBB) is a modulated anatomophysiological interface which separates and controls substance exchange between the blood and the brain parenchyma; therefore, it is particularly exposed to ART-induced toxicity. Balancing the health risks and gains of ART has to be considered in order to maximize the positive effects of therapy. The current review discusses the cerebrovascular toxicity of ART, with the focus on mitochondrial dysfunction. Graphical Abstract Graphical representation of the interactions between HIV, antiretroviral therapy (ART), and the blood-brain barrier (BBB).

Trends and perioperative outcomes of patients with human immunodeficiency virus (HIV) undergoing lower extremity revascularization

The development of highly active antiretroviral therapy (HAART) has significantly improved the life expectancy of patients with human immunodeficiency virus (HIV), but has led to the rise of chronic conditions including peripheral artery disease (PAD). However, trends and outcomes among patients with HIV undergoing lower extremity revascularization are poorly characterized. The aim of this study was to investigate the trends and perioperative outcomes of lower extremity revascularization among patients with HIV and PAD in a national database. The National Inpatient Sample (NIS) was reviewed between 2003 and 2014. All hospital admissions with a diagnosis of PAD undergoing lower extremity revascularization were stratified based on HIV status. Outcomes were assessed using propensity score matching and multivariable regression. Among all patients undergoing lower extremity revascularization for PAD, there was a significant increase in the proportion of patients with HIV from 0.21% in 2003 to 0.52% in 2014 (p < 0.01). Patients with HIV were more likely to be younger, male, and have fewer comorbidities, including coronary artery disease and diabetes, at the time of intervention compared to patients without HIV. With propensity score matching and multivariable regression, HIV status was associated with increased total hospital costs, but not length of stay, major amputation, or mortality. Patients with HIV with PAD who undergo revascularization are younger with fewer comorbidities, but have increased hospital costs compared to those without HIV. Lower extremity revascularization for PAD is safe for patients with HIV without increased risk of in-hospital major amputation or mortality, and continues to increase each year.

HIV-related cardiovascular disease: any role for high-density lipoproteins?

The introduction of antiretroviral therapy (ART) has improved the life expectancy of patients infected with human immunodeficiency virus (HIV). However, this population is at an increased risk for noncommunicable diseases, including atherosclerotic cardiovascular disease (CVD). Both ART and viral infection may be potential contributors to the pathophysiology of HIV-related CVD. The mechanisms behind this remain unclear, but it is critical to delineate early biomarkers of cardiovascular risk in the HIV population. In this review, we postulate that potential biomarkers could include alterations to high-density lipoprotein (HDL). Indeed, recent data suggest that HIV and ART may induce structural changes of HDL, thus resulting in shifts in HDL subclass distribution and HDL functionality.

Characterization of inpatient rehabilitation outcomes among HIV/AIDS patients: a retrospective cohort study

ABSTRACT Survival time in HIV/AIDS patients has increased as a result of improved treatments, but many acquire functional impairments that may necessitate multidisciplinary medical rehabilitation. In the United States, inpatient rehabilitation facilities (IRF) provide this care, but outcomes are not well described in this population. We used the Uniform Data System for Medical Rehabilitation (UDSMR) database to describe 11,051 HIV/AIDS IRF patients; HIV/AIDS patients were grouped according to the following admission criteria: (1) HIV/AIDS as primary reason for admission (n = 225); (2) HIV/AIDS symptomatic comorbidity (n = 6569); and (3) HIV/AIDS asymptomatic comorbidity (n = 4257). We used standard descriptive statistics to summarize demographic, medical, rehabilitation, and discharge setting characteristics by group. When compared to patients with HIV/AIDS as a comorbidity, primary HIV/AIDS patients had worse outcomes. They made less functional change (25.1 versus 29.8 and 28.9, p < .001), went home less (73.8% versus 74.5% and 77.8%, p < .001) and to an acute care hospital more frequently (18.2% versus 13.9% and 10.1%, p < .001). These findings help to characterize the HIV/AIDS patient population who receive inpatient medical rehabilitation, which helps inform clinical care, and highlight the positive impact IRF care can make to minimize functional disability among chronic HIV/AIDS patients and possibly decrease costs of home health care.

Effects of HIV-1 gp120 and tat on endothelial cell sensescence and senescence-associated microRNAs

The aim of this study was to determine, in vitro, the effects of X4 and R5 HIV‐1 gp120 and Tat on: (1) endothelial cell senescence and (2) endothelial cell microRNA (miR) expression. Endothelial cells were treated with media without and with: R5 gp120 (100 ng/mL), X4 gp120 (100 ng/mL), or Tat (500 ng/mL) for 24 h and stained for senescence‐associated β‐galactosidase (SA‐β‐gal). Cell expression of miR‐34a, miR‐217, and miR‐146a was determined by RT‐PCR. X4 and R5 gp120 and Tat significantly increased (~100%) cellular senescence versus control. X4 gp120 significantly increased cell expression of miR‐34a (1.60 ± 0.04 fold) and miR‐217 (1.52 ± 0.18), but not miR‐146a (1.25 ± 0.32). R5 gp120 significantly increased miR‐34a (1.23 ± 0.07) and decreased miR‐146a (0.56 ± 0.07). Tat significantly increased miR‐34a (1.49 ± 0.16) and decreased miR‐146a (0.55 ± 0.23). R5 and Tat had no effect on miR‐217 (1.05 ± 0.13 and 1.06 ± 0.24; respectively). HIV‐1 gp120 (X4 and R5) and Tat promote endothelial cell senescence and dysregulation of senescence‐associated miRs.

Ginsenoside Rb1 Blocks Ritonavir-Induced Oxidative Stress and eNOS Downregulation through Activation of Estrogen Receptor-Beta and Upregulation of SOD in Human Endothelial Cells

We have previously shown that ritonavir (RTV), a highly active anti-retroviral therapy (HAART) drug, can cause endothelial dysfunction through oxidative stress. Several antioxidants including ginsenoside Rb1, a compound with antioxidant effect, can effectively block this side effect of RTV in endothelial cells. In the current study, we explored a mechanism by which ginsenoside Rb1 could protect these cells via binding of estrogen receptors (ERs). We found that several human endothelial cell lines differentially expressed ER-β and had very low levels of ER-α. RTV treatment significantly increased the production of reactive oxygen species (ROS) and decreased the expression of endothelial nitric oxidase synthase (eNOS) and superoxide dismutase (SOD) in HUVECs, while Rb1 effectively blocked these effects of RTV. These effects of Rb1 were effectively inhibited by silencing ER-β, indicating that ginsenoside Rb1 requires ER-β for its antioxidant activity in inhibiting the deleterious effect of RTV in human endothelial cells. Furthermore, Rb1 specifically activated ER-β transactivation activity by ER-β luciferase reporter assay. Rb1 competitively bound to ER-β, which was determined by the high sensitive fluorescent polarization assay.

Von Willebrand Factor Adhesive Activity and ADAMTS13 Protease Activity in HIV-1-Infected Men

Background: Endothelial activation caused by HIV-1 infection leads to release of von Willebrand factor (VWF), which enters the circulation or attaches to vessel walls and self-assembles into strings and fibers, enabling platelet adhesion; this adhesive activity is regulated by the VWF-cleaving protease ADAMTS13. Our objective was to assess VWF adhesive activity and ADAMTS13 protease activity in HIV-1 infection. Methods: We measured levels of VWF antigen, VWF activation factor (a measure of adhesive activity), ADAMTS13 antigen, ADAMTS13 activity, and apolipoprotein A1 (which interferes with VWF self-association) in serum samples from HIV-1-infected men whose infections were acute (n=10), chronic untreated (n=10), or chronic treated (n=10), compared to uninfected controls (n=10). Means across groups were compared using analysis of variance with contrasts, and Pearson correlations were calculated. Results: Plasma viral load was positively correlated with VWF adhesive activity, which was elevated in acute relative to chronic treated HIV-1 infection. ADAMTS13 antigen and activity were both positively correlated with plasma viral load, and ADAMTS13 activity was significantly higher in men with acute HIV infection than in uninfected controls, and in both acute and chronic untreated HIV infection relative to chronic treated infection. Conclusion: These findings suggest that even in the setting of increased ADAMTS13 protease activity, VWF in HIV-1 infection is hyperadhesive, which may favor development of microvascular and arterial thromboses and thereby contribute to increased cardiovascular risk in HIV-1-infected individuals.

Nephrotoxicity and highly active antiretroviral therapy: Mitigating action of Momordica charantia

Momordica charantia (M. charantia) is known for its antioxidant and antidiabetic properties. The aim of this study is to investigate the renoprotective effects of M. charantia in rats following treatment with highly active antiretroviral therapy (HAART) regimen triplavar. Adult male Sprague-Dawley rats weighing 178.1-220.5 g (n = 36) were divided into six groups (A-F) with each group comprising of six (n = 6) rats. The drugs and extract were administered via oral gavage. The therapeutic dose of triplavar was adjusted using the human therapeutic dose equivalent for the rat model. Animals were euthanized on the tenth week with kidneys removed for examination and blood obtained via cardiac puncture. Levels of oxidative stress enzymes (superoxide dismutase-SOD, catalase-CAT, and reduced glutathione-GSH) were significantly lowered in all groups not receiving M. charantia. The levels of thiobarbituric acid reactive substances (TBARS) were increased resulting in free radical formation via auto-oxidation. Renal parameters showed no albuminuria, normal blood urea nitrogen (BUN), serum creatinine (SCr) and electrolytes in groups treated with M. charantia. HAART treated (Group B) showed severe albuminuria, a significantly (p < 0.05) raised BUN and SCr and gross electrolyte disturbances. Blood glucose levels were significantly raised in groups not receiving the adjuvant M. charantia (p < 0.05). Histopathology in HAART treated animals showed glomerular capillary abnormalities and cellular infiltrations while M. charantia treated animals showed an essentially normal glomerular appearance with capillary loops and normal cytoarchitecture. In conclusion M. charantia extract administration improved blood glucose levels, restored renal histology, reinstate renal function, reduce body weight loss and restores hyperglycemia.

Association of T Cell and Macrophage Activation with Arterial Vascular Health in HIV

HIV-infected individuals are at increased risk of cardiovascular disease (CVD), but the arterial vascular functions affected by persistent innate and cellular immune activation are not well described. We assessed the relationship between immunologic and vascular parameters in 70 HIV-infected adults on efavirenz, tenofovir, and emtricitabine with more than 2 years of virologic suppression and no history of CVD. We measured brachial artery flow-mediated dilation (FMD) using ultrasound and circulating intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) by multiple immunoassay. We also measured circulating naive (CD45RO^-CCR7⁺CD27⁺), activated (CD38⁺ and CD38⁺DR⁺), exhausted (PD1⁺), senescent (CD57⁺), and memory (CD45RO⁺) CD4⁺ and CD8⁺ T cell subsets by flow cytometry, and macrophage activation markers by ELISA and multiple immunoassay. Regression models were adjusted for age, sex, smoking, duration of antiretroviral therapy (ART), and body mass index. Median age was 45 years (IQR 39, 50), median CD4⁺ count 701 cells/μl (IQR 540, 954), and 43% were female. Lower brachial FMD was associated with a higher percentage of activated CD8⁺ T cells (p < .01), but not associated with macrophage activation. In contrast, higher ICAM-1 and VCAM-1 were associated with sCD163 (p < = .01 for both), macrophage inflammatory protein-1α (p < = .02 for both), and sCD14 (p = .01 for ICAM-1 only). These findings are consistent with the hypothesis that circulating CD8⁺ T cell activation may impair arterial smooth muscle relaxation, while macrophage activation has a role in the expression of endothelial cell proteins involved in immune cell translocation. Both innate and cellular immune activation appear to promote arterial vascular disease in HIV-infected persons on ART using differing mechanisms.