Plasma IL-6 levels are independently associated with atherosclerosis and mortality in HIV-infected individuals on suppressive antiretroviral therapy

The impact of concurrent HIV and type II diabetes on immune maturation, immune regulation and immune activation

Chronic immune activation and inflammation are constant findings in people living with HIV (PLWH) and contribute to the risk of non-AIDS-related morbidities, including cardiovascular diseases (CVD). Type 2 diabetes (T2D) is also characterized by immune activation and inflammation. We aimed to investigate the impact of concurrent HIV infection and T2D on T-cell subsets. The study included PLWH with T2D (HIV+T2D+, N = 25) and without T2D (HIV+T2D-, N = 25) and HIV-negative controls with T2D (HIV-T2D+, N = 22) and without T2D (HIV-T2D-, N = 28). All PLWH in the study were receiving combination antiretroviral therapy. We examined T-cell homeostasis by determining T-cell subsets (immune maturation, immune regulation and immune activation) using flow cytometry. HIV+T2D- had lower proportion of Tc17 cells and higher proportion of apoptotic cells than HIV-T2D-. When comparing HIV+T2D+ and HIV+T2D- a lower proportion of CD4+ recent thymic emigrants (RTE) was found (p = 0.028). Furthermore, HIV+T2D+ had a higher proportion of non-suppressive CD4+ Tregs compared to HIV+T2D- (p = 0.010). In conclusion, even in the setting of treated HIV infection, distinct immunological alterations are found. In PLWH with concomitant T2D, most alterations in T-cell subsets were related to HIV and only few differences were found between PLWH with and without diabetes.

Serum Bovine Immunoglobulins Improve Inflammation and Gut Barrier Function in Persons with HIV and Enteropathy on Suppressive ART

Background

Systemic inflammation persists in chronic HIV infection and is associated with increased rates of non-AIDS events such as cardiovascular and liver disease. Increased gut permeability and systemic exposure to microbial products are key drivers of this inflammation. Serum-derived bovine immunoglobulin/protein isolate (SBI) supports gut healing in other conditions such as inflammatory bowel disease.

Methods

In this randomized, double-blind study, participants receiving suppressive antiretroviral therapy (ART) with chronic diarrhea received placebo or SBI at 2.5 g BID or 5 g BID for 4 weeks, followed by a 20-week placebo-free extension phase with SBI at either 2.5 or 5 g BID. Intestinal fatty acid binding protein (I-FABP), zonulin, flagellin, lipopolysaccharide (LPS) and LPS-binding protein, and inflammatory markers were measured by ELISA or multiplex assays. Non-parametric tests were used for analysis.

Results

One hundred three participants completed the study. By week 24 SBI significantly decreased circulating levels of I-FABP (-0.35 ng/μL, P=0.002) and zonulin (-4.90 ng/μL, P=0.003), suggesting improvement in gut damage, and interleukin-6 (IL-6) (-0.40 pg/μL, P=0.002), reflecting improvement in systemic inflammation. In participants with the lowest quartile of CD4+ T-cell counts at baseline (189-418 cells/μL), CD4+ T-cell counts increased significantly (26 cells/μL; P=0.002).

Conclusions

Oral SBI may decrease inflammation and warrants further exploration as a potential strategy to improve gut integrity and decrease systemic inflammation among persons receiving prolonged suppressive ART.

Cardiorespiratory fitness is associated with inflammation and physical activity in HIV+ adults

OBJECTIVE

Our objective was to examine the effect of a lifestyle diet and exercise intervention on cardiorespiratory fitness (CRF) and to examine predictors of change in CRF.

DESIGN

People living with HIV (PLHIV) are at increased risk for cardiovascular disease. CRF is a better predictor of cardiovascular disease-related mortality than established risk factors yet very little is known about CRF in PLHIV.

METHODS

One-hundred and seven virally suppressed PLHIV were randomized to a group-based intervention to improve lifestyle behaviors or a control condition. All PLHIV maximal cardiorespiratory stress test to determine VO2 peak, VO2 at anaerobic threshold, and ventilatory efficiency/VCO2, at baseline and 6 months later. Participants wore an accelerometer to measure physical activity, completed waist-hip circumference measures, and had a fasting lipid profile, IL-6, and high sensitivity C-reactive protein analyzed. Generalized estimating equations were used to examine the effect of the intervention on CRF and predictors of change in CRF.

RESULTS

Participants were approximately 53 years old, 65% male (n = 70), and 86% African-American (n = 93). There was no effect of the intervention on markers of CRF over time (P > 0.05). After controlling for age, sex, waist-hip-ratio, the inflammatory biomarker IL-6 was inversely associated with a decline in both VO2 peak (P = 0.03) and VO2 at anaerobic threshold (P = 0.03). In addition, participants who walked an additional 10 000 steps per day had a 2.69 ml/kg per min higher VO2 peak (P = 0.02).

CONCLUSION

Despite HIV viral suppression, PLHIV had remarkably poor CRF and inflammation was associated with a clinically adverse CRF profile. However, increased physical activity was associated with improved CRF.

Computer-assisted prediction of atherosclerotic intimal thickness based on weight of adrenal gland, interleukin-6 concentration, and neural networks

Objective

Methods

Results

Conclusions

Inflammatory biomarkers and subclinical carotid atherosclerosis in HIV-infected and HIV-uninfected men in the Multicenter AIDS Cohort Study

BACKGROUND

HIV-infected persons have an increased risk of atherosclerosis relative to uninfected individuals. Inflammatory processes may contribute to this risk. We evaluated the associations of 10 biomarkers of systemic inflammation (CRP, IL-6, sTNF-αR1 and 2), monocyte activation (CCL2, sCD163, sCD14), coagulation (fibrinogen, D-dimer), and endothelial dysfunction (ICAM-1) with subclinical carotid atherosclerosis among participants in the Multicenter AIDS Cohort Study (MACS).

METHODS

Carotid plaque and intima media thickness (IMT) in the common carotid (CCA-IMT) and bifurcation region were assessed by B mode ultrasound among 452 HIV-infected and 276 HIV-uninfected men from 2010-2013. Associations between levels of each biomarker and presence of focal plaque and IMT were assessed by logistic and linear regression models, adjusting for demographics, risk behaviors, traditional cardiovascular disease (CVD) risk factors, and HIV disease characteristics.

RESULTS

Compared to HIV-uninfected men, HIV-infected men had significantly higher levels of 8 of the 10 biomarkers. Overall, men with sCD163, CCL2, IL-6, and CRP levels in the highest quintile had approximately 2 times the odds of carotid plaque relative to those with levels in the lowest quintile, independent of demographic and CVD risk factors. Fibrinogen levels were positively associated with CCA-IMT while ICAM-1, CCL2, and sTNF-αR1 levels were positively associated with bifurcation-IMT. Among HIV-uninfected men, higher levels of sTNF-αR2 were positively associated with CCA-IMT, fibrinogen with bifurcation-IMT and carotid plaque, and ICAM-1 with carotid plaque.

CONCLUSION

In addition to greater levels of systemic inflammation, heightened monocyte activation (sCD163, CCL2) may contribute to the burden of atherosclerosis among HIV-infected persons.

Biomarkers of aging in HIV: inflammation and the microbiome

PURPOSE

HIV-infected subjects present increased levels of inflammatory cytokines and T cell activation in the peripheral blood despite suppressive combination antiretroviral therapy which renders them susceptible to premature aging. The purpose of the present work was to review existing evidence on the ways in which the anatomical and microbiological abnormalities of the gastrointestinal tract can represent a major cause of organ disease in HIV infection.

METHODS

We conducted a systematic review of the Pubmed database for articles published from 2014 to 2018. We included studies on inflammatory/activation biomarkers associated with cardiovascular and bone disease, neurocognitive impairment and serious non-AIDS events in HIV-infected subjects. We also included researches which linked peripheral inflammation/activation to the anatomical, immune and microbiological alterations of the gastrointestinal tract.

RESULTS

Recent literature data confirm the association between non-infectious comorbidities and inflammation in HIV infection which may be driven by gastrointestinal tract abnormalities, specifically microbial translocation and dysbiosis. Furthermore, there is mounting evidence on the possible role of metabolic functions of the microbiota in the pathogenesis of premature aging in the HIV-infected population.

CONCLUSIONS

Biomarkers need to be validated for their use in the management of HIV infection. Compounds which counteract microbial translocation, inflammation and dysbiosis have been investigated as alternative therapeutic strategies in viro-suppressed HIV-infected individuals, but appear to have limited efficacy, probably due to the multifactorial pathogenesis of non-infectious comorbidities in this setting.

Mechanisms of Cardiovascular Disease in the Setting of HIV Infection

Although the initial reports of increased cardiovascular (CV) disease in the setting of advanced AIDS were reported approximately 30 years ago, advances in antiretroviral therapy and immediate initiation of therapy on diagnosis have transformed what was once a deadly infectious disease into a chronic health condition. Accordingly, the types of CV diseases occurring in HIV have shifted from pericardial effusions and dilated cardiomyopathy to atherosclerosis and heart failure. The underlying pathophysiology of HIV-associated CV disease remains poorly understood, partly because of the rapidly evolving nature of HIV treatment and because clinical endpoints take many years to develop. The gut plays an important role in the early pathogenesis of HIV infection as HIV preferentially infects CD4+ T cells, 80% of which are located in gut mucosa. The loss of these T cells damages gut mucosa resulting in increased gut permeability and microbial translocation, which incites chronic inflammation and immune activation. Antiretroviral therapy does not cure HIV infection and immune abnormalities persist. These abnormalities correlate with mortality and CV events. The effects of antiretroviral therapy on CV risk are complex; treatment reduces inflammation and other markers of CV risk but induces lipid abnormalities, most commonly hypertriglyceridemia. On a molecular level, monocytes/macrophages, platelet reactivity, and immune cell activation, which play a role in the general population, may be heightened in the setting of HIV and contribute to HIV-associated atherosclerosis. Chronic inflammation represents an inviting therapeutic target in HIV, as it does in uninfected persons with atherosclerosis.

Carotid artery atherosclerosis is associated with mortality in HIV-positive women and men

OBJECTIVE

Among people with HIV, there are few long-term studies of noninvasive ultrasound-based measurements of the carotid artery predicting major health events. We hypothesized that such measurements are associated with 10-year mortality in the Women's Interagency HIV Study (WIHS) and Multicenter AIDS Cohort Study (MACS), and that associations differ by HIV serostatus.

DESIGN

Nested cohort study.

METHODS

Participants without coronary heart disease underwent B-mode carotid artery ultrasound, with measurement of common carotid artery intima-media thickness (IMT); carotid artery plaque (focal IMT > 1.5 mm) at six locations; and Young's modulus of elasticity, a measure of arterial stiffness. We examined all-cause mortality using Cox models, controlling for demographic, behavioral, cardiometabolic, and HIV-related factors.

RESULTS

Among 1722 women (median age 40 years, 90% nonwhite, 71% HIV-positive) and 1304 men (median age 50, 39% nonwhite, 62% HIV-positive), 11% died during follow-up. Mortality was higher among HIV-positive women [19.9 deaths/1000 person-years, 95% confidence interval (CI) 14.7-28.8] than HIV-positive men (15.1/1000, 95% CI 8.3-26.8). In adjusted analyses, plaque was associated with mortality (hazard ratio 1.44, 95% CI 1.10-1.88) regardless of HIV serostatus, and varied by sex (among women, hazard ratio 1.06, 95% CI 0.74-1.52; among men; hazard ratio 2.19, 95% CI 1.41-3.43). The association of plaque with mortality was more pronounced among HIV-negative (hazard ratio 3.87, 95% 1.95-7.66) than HIV-positive participants (hazard ratio 1.35, 95% CI 1.00-1.84). Arterial stiffness was also associated with mortality (hazard ratio 1.43 for highest versus lowest quartile, 95% CI 1.02-2.01). Greater common carotid artery-IMT was not associated with mortality.

CONCLUSION

Carotid artery plaque was predictive of mortality, with differences observed by sex and HIV serostatus.

Biochemical Assessment: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

The Tehran Lipid and Glucose Study (TLGS) is a community-based study to reveal the frequency of non-communicable diseases (NCDs) in Tehran's population. This research consists of two main parts, a cross-sectional study on the prevalence of cardiovascular risk factors and a 20-year-ongoing prospective cohort study, which was initiated in 1999 in several phases with an approximate duration of 3.6 years, and is still ongoing. The aim of the present study is review the 20 year biochemical findings of the TLGS related to the NCDs in a large sample.

METHODS

All articles on biochemical assessments derived from the TLGS from the earliest publications (2002) until 30 January 2018 were reviewed for their findings on different risk factors of NCDs.

RESULTS

According to the TLGS findings high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), homocysteine (Hcy), age, smoking, hypertension, and obesity were the most important risk factors of cardiovascular diseases (CVD). It was illustrated that in subjects with abdominal obesity, the hs-CRP and IL-6 serum levels were higher than in normal subjects. The most appropriate prognostic indexes and associations were for hs-CRP, IL-6, and Hcy with abdominal obesity, waist circumference, WHtR, and wrist circumference, respectively. Previous studies have demonstrated a direct relationship between obesity and serum levels of inflammatory factors.

CONCLUSIONS

According to the results of TLGS, serum levels of biochemical risk factors such as hs-CRP, IL-6, and Hcy could be beneficial in early diagnosis and effective treatment of cardiovascular, obesity and other metabolic diseases.

Vascular endothelial dysfunction in the wake of HIV and ART

Mounting evidence points to increased rates of cardiovascular disease (CVD) among people living with HIV/AIDS (PLWHA). Endothelial dysfunction (loss of endothelium-dependent vascular relaxation in response to provasodilatory stimuli) constitutes an early pathophysiological event in atherogenesis and CVD. Both HIV-1 infection and antiretroviral therapy (ART) are implicated in the development of endothelial dysfunction; however, conclusions are frequently drawn from associations shown in epidemiological studies. In this narrative review of mainly in vitro and animal studies, we report on the current understanding of how various HIV-1 proteins, HIV-1-induced proinflammatory cytokines and common antiretroviral drugs directly impact vascular endothelial cells. Proposed cellular mechanisms underlying the switch to a dysfunctional state are discussed, including oxidative stress, impaired expression and regulation of endothelial nitric oxide (NO) synthase (eNOS) and increased expression of vascular adhesion molecules. From the literature, it appears that increased reactive oxygen species (ROS) production, linked to decreased NO bioavailability and ensuing endothelial dysfunction, may be proposed as a putative final common pathway afflicting the vascular endothelium in PLWHA. The HIV-1-proteins Tat, Gp120 and Nef in particular, the proinflammatory cytokine, TNF-α, and the antiretroviral drugs Efavirenz and Lopinavir, most commonly postulated to be primary causal agents of endothelial dysfunction, are also discussed. We conclude that, despite existing evidence from basic research papers, a significant gap remains in terms of the exact underlying cellular mechanisms involved in HIV-1 and ART induced endothelial dysfunction. Bridging this gap could help pave the way for future strategies to prevent and treat early cardiovascular changes in PLWHA.

Epidemiology of ischemic heart disease in HIV

PURPOSE OF REVIEW

The purpose of this review is to summarize and synthesize recent data on the risk of ischemic heart disease (IHD) in HIV-infected individuals.

RECENT FINDINGS

Recent studies in the field demonstrate an increasing impact of cardiovascular disease (CVD) on morbidity and mortality in HIV relative to AIDS-related diagnoses. Studies continue to support an approximately 1.5 to two-fold increased risk of IHD conferred by HIV, with specific risk varying by sex and virologic/immunologic status. Risk factors include both traditional CVD risk factors and novel, HIV-specific factors including inflammation and immune activation. Specific antiretroviral therapy (ART) drugs may increase CVD risk, yet the net effect of ART with viral suppression is beneficial with regard to CVD risk. Management of cardiovascular risk and prevention of CVD is complex, because current general population strategies target traditional CVD risk factors only. Extensive investigation is being directed at developing tailored CVD risk prediction algorithms and interventions to reduce CVD risk in HIV.

SUMMARY

Increased IHD risk is a significant clinical and public health challenge in HIV. The development and application of HIV-specific interventions to manage CVD risk factors and reduce CVD risk will improve the long-term health of this ageing population.

HIV disease is associated with increased biomarkers of endothelial dysfunction despite viral suppression on long-term antiretroviral therapy in Botswana

Background

Untreated HIV infection is associated with increased biomarkers of endothelial dysfunction. However, the predictors and degree of endothelial dysfunction among virally suppressed HIV–infected adults on long–term antiretroviral therapy (ART) have not been well studied in sub– Saharan Africa (SSA).

Methods

We enrolled 112 HIV–infected adults with virological suppression on long–term ART and 84 HIV–uninfected controls in Botswana. We measured plasma levels of markers of endothelial injury [soluble vascular adhesion molecule 1 (VCAM–1), intercellular adhesion molecule 1 (ICAM–1) and E–selectin] and plasma levels of biomarkers of inflammation [interleukin 6 (IL–6)] and monocyte activation (sCD163). Baseline traditional cardiovascular disease (CVD) risk factors and bilateral common carotid intima–media thickness (cIMT) were also available for all participants. We assessed whether HIV status (despite virological suppression on ART) was associated with biomarkers of endothelial dysfunction after controlling for traditional CVD risk factors in linear regression models. We additionally assessed the association between IL–6, sCD163 and cIMT with endothelial dysfunction in separate multivariate linear regression models, controlling for cIMT, among virally suppressed HIV–infected participants only.

Results

In multivariate analysis, HIV infection was significantly associated with increased VCAM–1 (p < 0.01) and ICAM–1 (p = 0.03) but not E–selectin (p = 0.74) levels. Within the HIV–positive group, higher sCD163 levels were associated with decreased ICAM–1 and E–selectin (p < 0.01 and p = 0.01, respectively) but not VCAM–1 (p = 0.13) levels. IL–6 was not associated with any of the biomarkers of endothelial dysfunction.

Conclusion

HIV disease was associated with biomarkers of endothelial dysfunction among virally suppressed adults in Botswana on long–term ART after controlling for traditional CVD risk factors. Future work should explore the clinical impact of persistent endothelial dysfunction following longterm HIV viral suppression on the risk of CVD clinical endpoints among HIV–infected patients in this setting.

Cardiovascular markers of inflammation and serum lipid levels in HIV-infected patients with undetectable viremia

Patients successfully treated for HIV infection still have an increased risk for cardiovascular morbidity and mortality, which might be related not only to traditional risks, but also to inflammation and dyslipidemia. We examined the relationship of serum lipid levels with plasma biomarkers of inflammation using a composite inflammatory burden score (IBS) based on individual (>75^th percentile) measurements from the following seven markers: CD40L, tPA, MCP-1, IL-8, IL-6, hCRP and P-selectin. IBS was categorized as 0 (none of the biomarkers >75^th percentile), 1, 2 and 3 or more scores. Correlations between the IBS and lipid parameters were examined by ordered logistic regression proportional odds models to estimate the odds of more elevated biomarkers. 181 male patients with undetectable HIV-viremia were included into the study. In the multivariate model, a one-unit increase (mmol/L) of total cholesterol and triglycerides was associated with a 1.41-fold (95% CI, 1.13–1.76) and 1.37-fold (95% CI, 1.18–1.60) increased odds of having a greater IBS, respectively. Those with an IBS score ≥1 compared to none had 2.14 (95% CI, 1.43–3.20) higher odds of having a one-unit increased total cholesterol/HDL-cholesterol ratio. In successfully treated HIV-infected persons dyslipidemia was associated with inflammation.

The impact of long-term moderate and heavy alcohol consumption on incident atherosclerosis among persons living with HIV

BACKGROUND

Level of alcohol consumption is associated with differential risk of atherosclerosis, but little research has investigated this association among HIV+ persons. We evaluated the association between long-term alcohol use and incident atherosclerosis among HIV+ persons.

METHODS

We utilized data from HIV+ participants of the Women's Interagency HIV Study (n=483) and the Multicenter AIDS Cohort Study (n=305) without history of cardiovascular disease. Atherosclerosis was assessed two times by B-mode carotid artery ultrasound imaging from 2004 to 2013. Presence of plaque was defined as focal carotid intima-media thickness over 1.5mm. Those with no plaque at baseline and plaque at follow-up were considered incident cases of atherosclerosis. Group-based trajectory models were used to categorize participants into 10-year drinking patterns representing heavy, moderate, or abstinent-low. Multivariable logistic regressions were conducted to assess the association of long-term moderate and heavy use on atherosclerosis, compared to abstinent-low.

RESULTS

Heavy alcohol consumption was not statistically significantly associated with risk for incident atherosclerosis in women (AOR 1.10, CI 0.40-3.02) or men (AOR 1.31, CI 0.43-4.00), compared to abstinence-low. Moderate consumption was associated with 54% lower odds for incident disease in men (AOR 0.46, CI 0.21-1.00), but not in women (AOR 1.08, CI 0.58-2.00). In cohort-combined analyses, alcohol consumption was not statistically significantly association with incident atherosclerosis (moderate AOR 0.78, CI 0.48-1.27; heavy AOR 1.33, CI 0.66-2.69).

CONCLUSION

Moderate alcohol consumption was associated with a significant protective effect on incident atherosclerosis in men only. No other levels of alcohol consumption significantly predicted atherosclerosis in men and women compared to abstinent-low.

Serum suppression of tumorigenicity 2 level is an independent predictor of all-cause mortality in HIV-infected patients

OBJECTIVE

To evaluate the predictive value of soluble suppression of tumorigenicity 2 (sST2), a decoy receptor of IL-33 involved in several inflammatory and immune diseases, for death in HIV infection.

DESIGN

Patients enrolled in the ANRS CO3 Aquitaine Cohort, a prospective hospital-based cohort of HIV-1-infected patients, who had a plasma sample available in the biobank were systematically eligible.

METHODS

sST2, soluble CD14 (sCD14) and IL-6 were measured using Luminex multiplex bead-based technology (R&D Systems) and a Bio-Plex 200 instrument (BioRad). Predictive capacities of sST2, sCD14, IL-6 and of the Veterans Aging Cohort Study clinical score at baseline on overall mortality were compared using multivariable Cox proportional hazards models.

RESULTS

During a median follow-up of 7.2 years [interquartile range (IQR): 6.0; 7.9], 93 deaths from all causes (incidence rate 9.9 per 1000 patient-years; 95% confidence interval 7.9-11.9) were reported in 1414 patients. The median sST2 baseline concentration was 22.9 ng/ml (IQR: 17.7; 30.3) and was higher (30.8 ng/ml, IQR: 21.5; 42.1) in patients who died as compared with those who stayed alive (22.6 ng/ml; IQR: 17.5; 29.6) (P < 10). An increased risk of death of 21% for a concentration 10.0 ng/ml higher of sST2 remained after adjustment for sCD14, IL-6 and Veterans Aging Cohort Study score (adjusted hazard ratio: 1.21; P < 10). The predictive capacity of sST2 was confirmed in a validation cohort (n = 386, 31 deaths) with an improved area c-index from 0.804 without sST2 to 0.811 with sST2.

CONCLUSION

sST2 is a new valuable biomarker to evaluate the risk of all-cause mortality in HIV disease.

Robust immunosensing system based on biotin-streptavidin coupling for spatially localized femtogram mL-1 level detection of interleukin-6

Detection of a very low amount of cytokines such as interleukin-6 (IL-6) in clinical fluids is important in biomedical research and clinical applications. Here, we demonstrate spatially-localized ultrasensitive (femtogram mL^-1) level detection of IL-6 in serum and in cell culture media. Our approach is based on a sandwich immunosensor fabricated on the surface of an optical fibre. Firstly, the biotinylated IL-6 capture antibody was immobilized on the fibre surface by biotin-streptavidin coupling. Then the fabricated fibre was used for capturing IL-6 followed by exposure to detection antibody which was labeled with the fluorescent magnetic nanoparticles to report the signal. A linear relationship between IL-6 concentration and the fluorescence signal was obtained in the range from 0.4pgmL^-1 to 400pgmL^-1 of IL-6, with the limit of detection down to 0.1pgmL^-1. In addition, this optical fibre sensor was successfully applied for the localized detection of IL-6 with the spatial resolution of 200µm and a sample volume of 1µL. Finally, the performance of the fibre sensor was demonstrated by detection of IL-6 secreted by BV-2 cells with comparable performance of the conventional enzyme-linked immunosorbent assay (ELISA).

Presence, Characteristics, and Prognostic Associations of Carotid Plaque Among People Living With HIV

BACKGROUND

Data from broad populations have established associations between incidental carotid plaque and vascular events. Among people living with HIV (PLWHIV), the risk of vascular events is increased; however, whether incidental carotid plaque is increased and there is an association between incidental carotid plaque, plaque characteristics, and vascular events among PLWHIV is unclear.

METHODS AND RESULTS

Data from the multi-institutional Research Patient Data Registry were used. Presence and characteristics (high-risk plaque, including spotty calcification and low attenuation) of carotid plaque by computerized tomography among PLWHIV without known vascular disease were described. Data were compared with uninfected controls similar in age, sex, and cardiovascular risk factors, including diabetes mellitus, hyperlipidemia, and cigarette smoking to cases. Primary outcome was an atherosclerotic cardiovascular disease event, and secondary outcome was ischemic stroke. Cohort consisted of 209 PLWHIV (45±10 years, 72% male) and 168 controls. Using computerized tomography, PLWHIV without vascular disease had higher rates of any carotid plaque (34% versus 25%; P=0.04), noncalcified (18% versus 5%; P<0.001) and high-risk plaque (25% versus 16%; P=0.03). Over a follow-up of 3 years, 19 atherosclerotic cardiovascular disease events (9 strokes) occurred. Carotid plaque was independently associated with a 3-fold increase in atherosclerotic cardiovascular disease events among PLWHIV (hazard ratio, 2.91; confidence interval, 1.10-7.7, P=0.03) and a 4-fold increased risk of stroke (hazard ratio, 4.43; confidence interval, 1.17-16.70; P=0.02); high-risk plaque was associated with a 3-fold increased risk of atherosclerotic cardiovascular disease events and a 4-fold increased risk of stroke.

CONCLUSIONS

There is an increase in incidental carotid plaque, noncalcified plaque, and high-risk plaque among PLWHIV, and the presence and characteristics of carotid plaque are associated with subsequent vascular events.

Subclinical herpesvirus shedding among HIV-1-infected men on antiretroviral therapy

OBJECTIVE

We evaluated the subclinical shedding of six different herpesviruses in antiretroviral drug-treated HIV-positive [HIV(+)] MSM, and determined how this is associated with markers of inflammation and immune activation.

METHODS

We obtained blood, semen, throat washing, urine, and stool from 15 antiretroviral-treated HIV-1-infected MSM with CD4 T-cell reconstitution, and 12 age-matched HIV-negative [HIV (-)] MSM from the Multicenter AIDS Cohort Study at four timepoints over 24 weeks to measure DNA levels of cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus 1 and 2, human herpesvirus 6 (HHV6), and HHV8. T-cell activation and plasma levels of soluble markers of inflammation and activation were also measured at the corresponding timepoints.

RESULTS

HIV(+) participants had a trend for higher total herpesvirus shedding rate. HIV(+) participants also had a significantly higher rate of shedding EBV and CMV compared with the HIV(-) group. Herpesvirus shedding was mostly seen in throat washings. In the HIV(+) group, herpesvirus shedding rate inversely correlated with plasma levels of interferon γ-induced protein 10 and soluble CD163. CMV DNA levels negatively correlated with levels of T-cell activation. There was a trend for a positive correlation between EBV shedding rate and plasma soluble CD14. HHV6 shedding rate negatively correlated with plasma levels of interleukin-6, soluble CD163, and interferon gamma-induced protein 10. Correlations were not observed among HIV(-) individuals.

CONCLUSION

Among treated HIV-infected MSM, there are higher subclinical shedding rates of some herpesviruses that occur in different body compartments and negatively correlate with levels of inflammation and immune activation.

Aging, Health, and Quality of Life for Older People Living With HIV in Sub-Saharan Africa: A Review and Proposed Conceptual Framework

OBJECTIVE

The number of people living with HIV (PLWH) over 50 years old in sub-Saharan Africa is predicted to triple in the coming decades, to 6-10 million. Yet, there is a paucity of data on the determinants of health and quality of life for older PLWH in the region.

METHODS

A review was undertaken to describe the impact of HIV infection on aging for PLWH in sub-Saharan Africa.

RESULTS

We (a) summarize the pathophysiology and epidemiology of aging with HIV in resource-rich settings, and (b) describe how these relationships might differ in sub-Saharan Africa, (c) propose a conceptual framework to describe determinants of quality of life for older PLWH, and (d) suggest priority research areas needed to ensure long-term gains in quality of life for PLWH in the region.

CONCLUSIONS

Differences in traditional, lifestyle, and envirnomental risk factors, as well as unique features of HIV epidemiology and care delivery appear to substantially alter the contribution of HIV to aging in sub-Saharan Africa. Meanwhile, unique preferences and conceptualizations of quality of life will require novel measurement and intervention tools. An expanded research and public health infrastructure is needed to ensure that gains made in HIV prevention and treamtent are translated into long-term benefits in this region.

Evaluation of HIV-DNA and inflammatory markers in HIV-infected individuals with different viral load patterns

BACKGROUND

Persistent residual viremia (RV) and low grade inflammation and immune activation have been associated with non-AIDS defining events. The impact of persistent RV and HIV-DNA load on immune activation/inflammation remains unclear. The purpose of this study was to gain new insights into the relation between viremia, markers of inflammation and HIV-DNA levels.

METHODS

Three hundred and twenty-one HIV-infected patients were studied. A retrospective analysis of viremia values, prospectively collected for 48 months, was performed. Patients were separated into three groups: 113 TND (Target Not Detected, patients with sustained undetectable viremia); 113 RV (Residual Viremia, patients who had at least three detectable viral load (VL) values <37 copies/ml); 95 LLV (Low Level Viremia, patients with at least two VL values >37 but <200 copies/ml). HIV-DNA, TNF-α, IL-6 and sCD14 were analyzed.

RESULTS

HIV-DNA, sCD14 and TNF-α were significantly lower in the TND group than in the RV and LLV groups. In addition, RV patients showed lower levels of HIV-DNA and sCD14 than LLV individuals. HIV-DNA load was not related to markers of inflammation. The ordinal logistic analysis showed that two independent variables were significantly associated with VL pattern: sCD14, HIV-DNA. In addition NRTIs plus NNRTIs and NRTIs plus PIs were negatively associated to VL pattern compared to INI-containing regimen.

CONCLUSIONS

Persistent undetectable viremia was associated with lower levels of inflammatory markers and HIV-DNA. However, the lack of normalization of these biomarkers in the TND group and the fact that HIV-DNA load was not associated with inflammation strongly suggest that other mechanisms play a major role in maintaining inflammation over time.

HIV-1-Associated Atherosclerosis: Unraveling the Missing Link

Cardiovascular disease, including atherosclerosis and atherosclerosis-associated complications, is an increasing cause of morbidity and mortality in human immunodeficiency virus (HIV) patients in the post-antiretroviral therapy era. HIV alone accelerates atherosclerosis. Antiretroviral therapy; HIV-associated comorbidities, such as dyslipidemia, drug abuse, and opportunistic infections; and lifestyle are risk factors for HIV-associated atherosclerosis. However, our current understanding of HIV-associated atherogenesis is very limited and has largely been obtained from clinical observation. There is a pressing need to experimentally unravel the missing link between HIV and atherosclerosis. Understanding these mechanisms will help to better develop and design novel therapeutic interventions for the treatment of HIV-associated cardiovascular disease. HIV mainly infects T cells and macrophages resulting in the induction of oxidative and endoplasmic reticulum stress, the formation of the inflammasome, and the dysregulation of autophagy. These mechanisms may contribute to HIV-associated atherogenesis. In this review, we will summarize our current understanding and propose potential mechanisms of HIV-associated atherosclerosis.

Utility of 2013 American College of Cardiology/American Heart Association Cholesterol Guidelines in HIV-Infected Adults With Carotid Atherosclerosis

BACKGROUND

Although HIV is associated with increased atherosclerotic cardiovascular disease (CVD) risk, it is unknown whether guidelines can identify HIV-infected adults who may benefit from statins. We compared the 2013 American College of Cardiology/American Heart Association and 2004 Adult Treatment Panel III recommendations in HIV-infected adults and evaluated associations with carotid artery intima-media thickness and plaque.

METHODS AND RESULTS

Carotid artery intima-media thickness was measured at baseline and 3 years later in 352 HIV-infected adults without clinical atherosclerotic CVD and not on statins. Plaque was defined as IMT >1.5 mm in any segment. At baseline, the median age was 43 (interquartile range, 39-49), 85% were men, 74% were on antiretroviral medication, and 50% had plaque. The American College of Cardiology/American Heart Association guidelines were more likely to recommend statins compared with the Adult Treatment Panel III guidelines, both overall (26% versus 14%; P<0.001), in those with plaque (32% versus 17%; P=0.0002), and in those without plaque (16% versus 7%; P=0.025). In multivariable analysis, older age, higher low-density lipoprotein cholesterol, pack per year of smoking, and history of opportunistic infection were associated with baseline plaque. Baseline IMT (hazard ratio, 1.18 per 10% increment; 95% confidence interval, 1.05-1.33; P=0.005) and plaque (hazard ratio, 2.06; 95% confidence interval, 1.02-4.08; P=0.037) were each associated with all-cause mortality, independent of traditional CVD risk factors.

CONCLUSIONS

Although the American College of Cardiology/American Heart Association guidelines recommended statins to a greater number of HIV-infected adults compared with the Adult Treatment Panel III guidelines, both failed to recommend therapy in the majority of HIV-affected adults with carotid plaque. Baseline carotid atherosclerosis but not atherosclerotic CVD risk scores was an independent predictor of mortality. HIV-specific guidelines that include detection of subclinical atherosclerosis may help to identify HIV-infected adults who are at increased atherosclerotic CVD risk and may be considered for statins.

Macrophage-derived foam cells impair endothelial barrier function by inducing endothelial-mesenchymal transition via CCL-4

Recently, endothelial-mesenchymal transition (EndMT) has been demonstrated to play an important role in the development of atherosclerosis, the molecular mechanisms of which remain unclear. In the present study, scanning electron microscopy directly revealed a widened endothelial space and immunohistofluorescence demonstrated that EndMT was increased in human aorta atherosclerotic plaques. M1 macrophage-derived foam cell (M1-FC) supernatants, but not M2 macrophage-derived foam cell (M2-FC) supernatants, induced EndMT. A protein array and enzyme-linked immunosorbent assay identified that the levels of several cytokines, including C-C motif chemokine ligand 4 (CCL-4) were increased in M1-FC supernatants, in which EndMT was promoted, accompanied by increased endothelial permeability and monocyte adhesion. Furthermore, anti-CCL-4 antibody abolished the effects of M1-FC supernatants on EndMT. At the same time, CCL-4 activated its receptor, C-C motif chemokine receptor-5 (CCR-5), and upregulated transforming growth factor-β (TGF-β) expression. Further experiments revealed that EndMT induced by CCL-4 was reversed by treatment with CCR-5 antagonist and the RNA-mediated knockdown of TGF-β. On the whole, the data of the present study suggest that M1-FCs induce EndMT by upregulating CCL-4, and increase endothelial permeability and monocyte adhesion. These data may help to elucidate the important role of EndMT in the development of atherosclerosis.

Effects of pitavastatin and pravastatin on markers of immune activation and arterial inflammation in HIV

OBJECTIVE

Persistent immune activation is thought to contribute to increased cardiovascular disease risk in HIV and statins may help modulate systemic immune activation. We aimed to compare the effects of two key statins on markers of systemic immune activation and arterial inflammation in the HIV population.

DESIGN

Double-blind, active-controlled, parallel-group comparative trial performed in 45 sites.

METHODS

Two hundred and fifty-two antiretroviral therapy-treated HIV-infected participants with dyslipidemia were randomized (1 : 1) to pitavastatin 4 mg daily vs. pravastatin 40 mg daily in the HIV-infected patieNts and TREatment with PItavastatin vs. pravastatin for Dyslipidemia (INTREPID) trial. In this analysis of the INTREPID trial, we assessed markers of immune activation and arterial inflammation using a modified intent-to-treat population. This trial is registered with ClinicalTrials.gov (NCT01301066).

RESULTS

One hundred and twenty-six participants were randomized to receive pitavastatin and 126 to pravastatin. Ninety-nine participants in the pitavastatin group and 91 participants in the pravastatin group completed the study. Median age was 50 (45, 56) years [median (interquartile range)]. Baseline, low-density lipoprotein-cholestrol (LDL-C) was 153 (135, 171) mg/dl, log HIV-1 viral load was 1.1 ± 0.2 copies/ml, and CD4 cell count was 580 (439, 794) cells/μl. At week 52, the pitavastatin group had a significantly greater reduction (% change) compared with pravastatin in soluble CD14 (sCD14), (-10.0 vs. 0.6%, P = 0.02), oxidized LDL (oxLDL) (-26.9 vs. -17.5%, P = 0.02), and lipoprotein-associated phospholipase 2 (Lp-PLA2) (-26.6 vs. -15.5%, P = 0.005) (pitavastatin vs. pravastatin).

CONCLUSION

Fifty-two weeks of pitavastatin 4 mg daily (vs. pravastatin 40 mg daily) led to a greater reduction in select markers of immune activation and arterial inflammation (sCD14, oxLDL, and LpPLA2) among HIV-infected participants. Further work is needed to assess whether immune-modulatory effects of pitavastatin reduce cardiovascular disease risk in HIV.

Respiratory health status is impaired in UK HIV-positive adults with virologically suppressed HIV infection

OBJECTIVES

We sought to evaluate whether people living with HIV (PLWH) using effective antiretroviral therapy (ART) have worse respiratory health status than similar HIV-negative individuals.

METHODS

We recruited 197 HIV-positive and 93 HIV-negative adults from HIV and sexual health clinics. They completed a questionnaire regarding risk factors for respiratory illness. Respiratory health status was assessed using the St George's Respiratory Questionnaire (SGRQ) and the Medical Research Council (MRC) breathlessness scale. Subjects underwent spirometry without bronchodilation.

RESULTS

PLWH had worse respiratory health status: the median SGRQ Total score was 12 [interquartile range (IQR) 6-25] in HIV-positive subjects vs. 6 (IQR 2-14) in HIV-negative subjects (P < 0.001); breathlessness was common in the HIV-positive group, where 47% compared with 24% had an MRC breathlessness score ≥ 2 (P = 0.001). Eighteen (11%) HIV-positive and seven (9%) HIV-negative participants had airflow obstruction. In multivariable analyses (adjusted for age, gender, smoking, body mass index and depression), HIV infection remained associated with higher SGRQ and MRC scores, with an adjusted fold-change in SGRQ Total score of 1.54 [95% confidence interval (CI) 1.14-2.09; P = 0.005] and adjusted odds ratio of having an MRC score of ≥ 2 of 2.45 (95% CI 1.15-5.20; P = 0.02). Similar findings were obtained when analyses were repeated including only HIV-positive participants with a viral load < 40 HIV-1 RNA copies/mL.

CONCLUSIONS

Despite effective ART, impaired respiratory health appears more common in HIV-positive adults, and has a significant impact on health-related quality of life.

Association of Arterial and Lymph Node Inflammation With Distinct Inflammatory Pathways in Human Immunodeficiency Virus Infection

Importance

Human immunodeficiency virus (HIV) infection is associated with a high risk of cardiovascular disease and increased arterial inflammation. In HIV, inflammation is also increased within lymph nodes (LNs), tissues known to harbor the virus even among treated and suppressed individuals.

Objective

To test the hypothesis that arterial inflammation is linked to HIV disease activity and to inflammation within HIV-infected tissues (LNs).

Design, Setting, and Participants

For this case-control study, participants were recruited from the SCOPE (Observational Study of the Consequences of the Protease Inhibitor Era) cohort, a clinic-based cohort of individuals receiving care at San Francisco General Hospital and the San Francisco Veteran's Affairs Medical Center. Arterial and LN inflammation were measured using 18F-fluorodeoxyglucose positron emission tomography. Detailed immunophenotyping was performed, along with measurement of viral activity/persistence and of circulating inflammatory biomarkers.

Main Outcomes and Measures

Arterial and LN inflammation.

Results

A total of 74 men were studied (45 HIV-infected men with a median age of 53 years [interquartile range, 49-59 years] and 29 uninfected male controls with a median age of 52 years [interquartile range, 46-56 years]). Lymph node inflammation was higher in HIV-infected individuals and correlated with markers of viral disease activity (viral load, CD8+ T cells, and CD4/CD8 ratio) and CD4+ T-cell activation. Uninfected controls had the lowest LN activity (mean [SD] maximum axillary LN standardized uptake value, 1.53 [0.56]), the elite controller and ART-suppressed groups had intermediate levels of LN (mean [SD] maximum axillary LN standardized uptake value, 2.12 [0.87] and 2.32 [1.79], respectively), and the noncontrollers had the highest activity (mean [SD] maximum axillary LN standardized uptake value, 8.82 [3.08]). Arterial inflammation was modestly increased in HIV-infected individuals and was positively correlated with circulating inflammatory biomarkers (high-sensitivity C-reactive protein and IL-6) and activated monocytes (CD14dimCD16+; nonclassical) but not with markers of HIV. While LN and arterial inflammation were increased in HIV, inflammatory activity in these tissues was not related (r = 0.09, P = .56).

Conclusions and Relevance

While LNs and, to a lesser degree, the arterial wall are inflamed in HIV, inflammation in these tissues is not closely linked. Namely, measures of HIV disease activity are strongly associated with LN inflammation but not with arterial inflammation. These data suggest that LN and arterial inflammation do not share underlying pathways of immune activation and also that therapeutic interventions that reduce viral disease activity may not predictably reduce arterial inflammation in HIV or its downstream consequence (ie, cardiovascular disease).

Replication of CMV in the gut of HIV-infected individuals and epithelial barrier dysfunction

Although invasive cytomegalovirus (CMV) disease is uncommon in the era of antiretroviral therapy (ART), asymptomatic CMV coinfection is nearly ubiquitous in HIV infected individuals. While microbial translocation and gut epithelial barrier dysfunction may promote persistent immune activation in treated HIV infection, potentially contributing to morbidity and mortality, it has been unclear whether CMV replication in individuals with no symptoms of CMV disease might play a role in this process. We hypothesized that persistent CMV replication in the intestinal epithelium of HIV/CMV-coinfected individuals impairs gut epithelial barrier function. Using a combination of state-of-the-art in situ hybridization technology (RNAscope) and immunohistochemistry, we detected CMV DNA and proteins and evidence of intestinal damage in rectosigmoid samples from CMV-positive individuals with both untreated and ART-suppressed HIV infection. Two different model systems, primary human intestinal cells differentiated in vitro to form polarized monolayers and a humanized mouse model of human gut, together demonstrated that intestinal epithelial cells are fully permissive to CMV replication. Independent of HIV, CMV disrupted tight junctions of polarized intestinal cells, significantly reducing transepithelial electrical resistance, a measure of monolayer integrity, and enhancing transepithelial permeability. The effect of CMV infection on the intestinal epithelium is mediated, at least in part, by the CMV-induced proinflammatory cytokine IL-6. Furthermore, letermovir, a novel anti-CMV drug, dampened the effects of CMV on the epithelium. Together, our data strongly suggest that CMV can disrupt epithelial junctions, leading to bacterial translocation and chronic inflammation in the gut and that CMV could serve as a target for therapeutic intervention to prevent or treat gut epithelial barrier dysfunction during HIV infection.

Differential Mechanisms of Inflammation and Endothelial Dysfunction by HIV-1 Subtype-B and Recombinant CRF02_AG Tat Proteins on Human Brain Microvascular Endothelial Cells: Implications for Viral Neuropathogenesis

The recombinant HIV-1 CRF02_AG is prevalent in West-Central Africa but its effects on the blood-brain barrier (BBB) and HIV-associated neurocognitive disorders (HAND) are not known. We analyzed the effects of Tat from HIV-1 subtype-B (Tat.B) and CRF02_AG (Tat.AG) on primary human brain microvascular endothelial cells (HBMEC), the major BBB component. Exposure of HBMEC to Tat.B increased IL-6 expression and transcription by 9- (P < 0.001) and 113-fold (P < 0.001), respectively, whereas Tat.AG increased IL-6 expression and transcription by 2.7-3.8-fold and 35.7-fold (P < 0.001), respectively. Tat.B induced IL-6 through the interleukin-1 receptor-associated kinase (IRAK)-1/4/mitogen-activated protein kinase kinase(MKK)/C-jun N-terminal kinase(JNK) pathways, in an activator protein-1(AP1)- and nuclear factor-kappaB (NFκB)-independent manner, whereas Tat.AG effects occurred via MKK/JNK/AP1/NFκB pathways. Tat-induced effects were associated with activation of c-jun (serine-63) and SAPK/JNK (Thr183/Tyr185). We demonstrated increased expression of transcription factors associated with these pathways (Jun, RELB, CEBPA), with higher levels in Tat.B-treated cells compared to Tat.AG. Functional studies showed that Tat.B and Tat.AG decreased the expression of tight junction proteins claudin-5 and ZO-1 and decreased the trans-endothelial electric resistance (TEER); Tat.B induced greater reduction in TEER, claudin-5, and ZO-1, compared to Tat.AG. Overall, our data showed increased inflammation and BBB dysfunction with Tat.B, compared to Tat.AG. This suggests these two HIV-1 subtypes differentially affect the BBB and central nervous system; our data provides novel insights into the molecular basis of these differential Tat-mediated effects.

Subclinical atherogenesis in patients with mild psoriasis: A role for IL-6?

Summary Introduction: A link of psoriasis with subclinical atherosclerosis has been postulated and cytokine network might intermediate this association. Few data are available in patients with mild psoriasis. We evaluated carotid intima-media thickness (cIMT) in drug-free psoriatic individuals and controls. In parallel, we searched for associations of cIMT with disease activity indexes and serum interleukins (IL) in psoriatic patients. Method: An experienced radiologist performed the cIMT analyses. Cytokine concentrations were assessed by flow cytometry. Disease activity was evaluated based on psoriasis area and severity index (PASI) as well as body surface area (BSA). Results: Sixty-five (65) patients and 64 controls were studied. Mean age of patients (50.9 years) did not differ from controls (p=0.362). A low PASI and BSA (< 10) prevailed (69.2% and 56.9%, respectively). Median levels of IL-12p70, TNF-α, IL-1β and IL-10 were significantly lower in cases than in controls (adjusted p<0.05), while IL-6 and IL-8 medians did not differ between groups (adjusted p>0.05). Smoking habit and diabetes mellitus predominated in cases (p=0.002). An altered cIMT (≥ 0.9 mm) was more frequent in cases than in controls (23.8% versus 8.5%, adjusted p=0.045). Mean cIMT was higher in cases with a borderline significance (p=0.057). cIMT scores did not correlate to PASI (rs=0.066; p=0.250) or BSA (rs=0.175; p=0.185), but did correlate significantly with serum IL-6 (rs=0.26; p=0.005). Conclusion: Subclinical atherosclerosis was more frequent in patients with mild psoriasis than controls. cIMT in psoriatic individuals correlated with serum IL-6, pointing to an eventual proatherogenic role of IL-6 in these patients. Newer studies should clarify the connection of atherogenesis with cytokines in psoriasis.

Emerging role of chemokine CC motif ligand 4 related mechanisms in diabetes mellitus and cardiovascular disease: friends or foes?

Chemokines are critical components in pathology. The roles of chemokine CC motif ligand 4 (CCL4) and its receptor are associated with diabetes mellitus (DM) and atherosclerosis cardiovascular diseases. However, due to the complexity of these diseases, the specific effects of CCL4 remain unclear, although recent reports have suggested that multiple pathways are related to CCL4. In this review, we provide an overview of the role and potential mechanisms of CCL4 and one of its major receptors, fifth CC chemokine receptor (CCR5), in DM and cardiovascular diseases. CCL4-related mechanisms, including CCL4 and CCR5, might provide potential therapeutic targets in DM and/or atherosclerosis cardiovascular diseases.