HIV-related mechanisms in atherosclerosis and cardiovascular diseases

Persistent low-level viraemia is associated with non-infectious comorbidities in an observational cohort in four African countries

INTRODUCTION

People living with HIV (PLWH) have higher rates of non-infectious comorbid diseases (NCDs) than individuals without HIV. We characterized the risk of NCDs among PLWH with undetectable viral load and persistent low-level viraemia (pLLV) in the African Cohort Study (AFRICOS). We secondarily quantified the role of immune activation in the association between LLV and NCDs.

METHODS

AFRICOS enrols participants in 12 clinics in Uganda, Kenya, Tanzania and Nigeria. Participants on antiretroviral therapy ≥ 6 months without an NCD at enrolment were included. PLLV was defined as at least two consecutive visits with a detectable viral load <1000 copies/ml. We examined elevated blood pressure, hypercholesterolemia, hyperglycaemia, renal insufficiency and a composite variable of any NCD. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard modelling. Among a subset of participants with biomarker data, we assessed the interaction between viral load and 13 biomarkers in the association with any NCD.

RESULTS

From 23 January 2013 to 1 December 2022, 1755 participants met the inclusion criteria for these analyses. At the first eligible visit, the majority of participants had an undetectable viral load (n = 1375, 78.35%). Participants with pLLV had an increased rate of developing any NCD (aHR: 1.22, 95% CI: 1.02-1.47) compared to participants with an undetectable viral load. There was a statistically significant interaction between LLV and TNF-α, CCL2/MCP-1 and TNF-RII in the association with any NCD.

CONCLUSIONS

PLLV was significantly associated with NCDs and immune inflammation in this population. Aggressive management of LLV may positively impact NCDs in PLWH.

HIV assisted partner services (aPS) to support integrated HIV and hypertension screening in Kenya: a pre-post intervention study

BACKGROUND

People living with HIV (PLWH) have a higher risk of developing hypertension compared to HIV uninfected individuals. HIV assisted partner services (aPS), where PLWH are assisted by a healthcare provider to disclose their status to sexual and / or drug injecting partner(s), offers an opportunity for integrated HIV and hypertension screening. We evaluated the feasibility of the aPS model in supporting integrated HIV and hypertension screening at the Kenyatta National Hospital, Kenya.

METHODS

Between August 2019 and December 2020, we conducted a pre-post intervention study. We enrolled women receiving HIV testing services (HTS) with confirmed hypertension (female index clients) and traced their male relatives for HIV and hypertension screening and reviewed management at 3-months. Hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg, diastolic blood pressure (DBP) ≥ 90 mmHg, and/or use of antihypertensive medication.

RESULTS

One hundred female index clients (median age: 55 years; interquartile range (IQR): 47-65) mentioned 165 male relatives (median: 49 years; IQR: 40-59) of whom 35% (n = 58/165) were enrolled. Of the male relatives, 29% had hypertension (n = 17/58), 34% had pre-hypertension (n = 20/58), and none were HIV-positive (n = 0/58). Among the female index clients, there was a statistically significant decline in SBP (pre: 156 mmHg, post: 133 mmHg, p-value: < 0.0001) and DBP (pre: 97 mmHg, post: 80 mmHg, p-value: < 0.0001), and increase in antihypertensive medication uptake (pre: 91%, n = 84/92; post: 98%, n = 90/92; X2: 4.3931, p-value: 0.036) relative to baseline. Among the male relatives, there was a statistically significant increase in antihypertensive medication uptake among those with hypertension (pre: 13%, n = 6/46; post: 17%, n = 8/46; X2: 32.7750, p-value: < 0.0001) relative to baseline.

CONCLUSION

HIV aPS holds promise for integrated HIV and hypertension screening among at-risk clients and their families. Twenty-nine percent of the male relatives had hypertension, higher than the national prevalence (24%), while one-third had pre-hypertension. We observed relatively high participant retention, reductions in blood pressure, and increase in antihypertensive medication uptake among those with confirmed hypertension. Future research expanding the aPS model to other non-communicable diseases through larger studies with longer follow-ups is required to better assess causal relationships and optimize integrated service delivery.

'My people perish for lack of knowledge': barriers and facilitators to integrated HIV and hypertension screening at the Kenyatta National Hospital, Nairobi, Kenya

INTRODUCTION

HIV and cardiovascular disease (CVD) are the two main causes of death in Kenya with hypertension as CVD's leading risk factor and HIV infection a risk factor for hypertension. We qualitatively evaluated the feasibility of integrated HIV and hypertension screening at Kenyatta National Hospital.

METHODS

We conducted two focus group discussions (FGDs) in November 2020 (female FGD: n=7; male FGD: n=8) to elicit facilitators, barriers and viability of integrated diagnosis and management of both conditions at HIV testing service (HTS) facilities. Participants were selected using convenience sampling and were not pair matched. All participants had received HTS. All female clients had confirmed hypertension, while male relatives had been contacted for HIV and hypertension screening through a modified assisted partner services model-where a trained healthcare provider supports notification. Transcripts were coded independently, and the codebook was developed and revised through consensus discussion. Data were analysed using thematic content analysis.

RESULTS

Main barriers to diagnosis and management included limited public awareness of hypertension risk factors and on improved treatment outcomes for those on lifelong HIV treatment, high cost of hypertension care despite free HIV care and healthcare system challenges especially medication stockouts. Strong support systems at family and healthcare levels facilitated care and treatment for both conditions. Participants recommended improved public awareness through individual-level communication and mass media campaigns, decentralised screening services for both HIV and hypertension, and either free or subsidised hypertension care services delivered alongside HIV treatment services. Most felt that an integrated HIV and hypertension service model was viable and would improve healthcare outcomes.

CONCLUSION

Patient-centred care models combining HIV and hypertension services hold promise for integrated service delivery.

Expression profile of microRNAs related with viral infectivity, inflammatory response, and immune activation in people living with HIV

Objective

To evaluate the serum expression of microRNAs (miRNAs) with ability to modulate the human immunodeficiency (HIV) replication or inflammatory status in people living with HIV (PLWH).

Methods

Forty healthy controls and two groups of PLWH were evaluated: (a) Group 1 (n = 30), patients with detectable viral load at inclusion, analyzed before receiving antiretroviral therapy (ART) and 12 months after initiating it; (b) Group 2 (n = 55), PLWH with prolonged undetectable viral load. Intestinal barrier disruption (I-FABP) and bacterial translocation (16S rDNA) markers, inflammatory markers such as interleukin (IL)-6 and sCD163, immune activation and expression of specific miRNAs were evaluated.

Results

Serum concentrations of I-FABP, 16S rDNA, IL-6, sCD163 and activated T lymphocytes were increased in PLWH. Serum miR-34a was overexpressed at inclusion and remained elevated after ART. The expression of the remaining miRNAs that modulate HIV infectivity (miR-7, mir-29a, miR-150, and miR-223) was similar in PLWH and controls. Related to miRNAs implicated in inflammation (miR-21, miR-155, and miR-210), significant overexpression were observed in miR-21 and miR-210 levels in untreated PLWH, but levels were restored in those patients treated for a long period.

Conclusion

A sustained overexpression of miR-34a was detected even after prolonged HIV controlled replication. miR-21 and miR-210 can be considered new markers of inflammation with high sensitivity to its modifications.

Regular aerobic exercise counteracts endothelial vasomotor dysfunction associated with insufficient sleep

Insufficient sleep is associated with endothelial vasomotor dysfunction and increased cardiovascular risk. Regular aerobic exercise is an effective lifestyle strategy for improving endothelial function and, in turn, reducing cardiovascular risk. We tested the hypotheses that regular aerobic exercise would 1) improve endothelial vasodilation and 2) decrease endothelin (ET)-1-mediated vasoconstrictor tone in middle-aged adults who chronically sleep <7 h/night. Thirty-six healthy, middle-aged adults were studied: 16 with normal sleep duration (age: 57 ± 2 yr; sleep duration: 7.4 ± 0.1 h/night) and 20 with short sleep duration (age: 56 ± 1 yr; sleep duration: 6.2 ± 0.1 h/night). The 20 short sleepers completed a 3-mo aerobic exercise training intervention. Forearm blood flow was determined (via plethysmography) in response to intra-arterial acetylcholine (ACh), BQ-123 (ET_A receptor antagonist), ACh + BQ-123, and sodium nitroprusside. Forearm blood flow responses to ACh were lower (∼20%; P < 0.05) in the short (from 4.2 ± 0.2 to 10.5 ± 0.6 mL/100 mL tissue/min) versus normal (4.2 ± 0.2 to 12.7 ± 0.6 mL/100 mL tissue/min) sleepers. In response to BQ-123, the short-sleep group had a significantly greater increase in resting forearm blood flow than the normal-sleep group (∼25% vs. ∼8%). ACh + BQ-123 resulted in a significant (∼25%) increase in the ACh-mediated vasodilation in the short-sleep group only. After exercise training, although nightly sleep duration was unchanged (6.4 ± 0.1 h/night), ACh-mediated vasodilation was significantly higher (∼20%), ET-1-mediated vasoconstriction was significantly lower (∼80%), and the vasodilator response to ACh was not increased with ET_A receptor blockade. Regular aerobic exercise, independent of changes in nightly sleep duration, can counteract insufficient sleep-related endothelial vasomotor dysfunction.NEW & NOTEWORTHY Habitual insufficient nightly sleep (<7 h/night) is associated with increased risk of cardiovascular disease and events. Endothelial dysfunction, specifically reduced endothelium-dependent vasodilation and increased endothelin (ET)-1-mediated vasoconstriction, is considered to be a major contributing mechanism underlying increased vascular risk with insufficient sleep. In contrast to insufficient sleep, regular aerobic exercise enhances endothelial vasomotor function, reducing the risk of cardiovascular disease and associated events. In the present study, we determined the effects of aerobic exercise training on endothelium-dependent vasodilation and ET-1 vasoconstriction in adults who habitually sleep <7 h/night. After exercise training, although nightly sleep duration was unchanged, endothelium-dependent vasodilation was significantly enhanced and ET-1-mediated vasoconstrictor tone was significantly reduced in adults who sleep <7 h/night. Regular aerobic exercise training can mitigate insufficient sleep-related endothelial vasomotor dysfunction and, in turn, potentially reduce the cardiovascular risk associated with habitual insufficient nightly sleep.

Circulating Microparticles Are Elevated in Treated HIV -1 Infection and Are Deleterious to Endothelial Cell Function

Background Circulating microparticles have emerged as biomarkers and effectors of vascular disease. Elevated rates of cardiovascular disease are seen in HIV -1-seropositive individuals. The aims of this study were to determine: (1) if circulating microparticles are elevated in antiretroviral therapy-treated HIV -1-seropositive adults; and (2) the effects of microparticles isolated from antiretroviral therapy -treated HIV -1-seropositive adults on endothelial cell function, in vitro. Methods and Results Circulating levels of endothelial-, platelet-, monocyte-, and leukocyte-derived microparticles were determined by flow cytometry in plasma from 15 healthy and 15 antiretroviral therapy-treated, virologically suppressed HIV -1-seropositive men. Human umbilical vein endothelial cells were treated with microparticles from individual subjects for 24 hours; thereafter, endothelial cell inflammation, oxidative stress, senescence, and apoptosis were assessed. Circulating concentrations of endothelial-, platelet-, monocyte-, and leukocyte-derived microparticles were significantly higher (≈35%-225%) in the HIV -1-seropositive compared with healthy men. Microparticles from HIV -1-seropositive men induced significantly greater endothelial cell release of interleukin-6 and interleukin-8 (≈20% and ≈35%, respectively) and nuclear factor-κB expression while suppressing anti-inflammatory microRNAs (miR-146a and miR-181b). Intracellular reactive oxygen species production and expression of reactive oxygen species -related heat shock protein 70 were both higher in cells treated with microparticles from the HIV -1-seropositive men. In addition, the percentage of senescent cells was significantly higher and sirtuin 1 expression lower in cells treated with HIV -1-related microparticles. Finally, caspase-3 was significantly elevated by microparticles from HIV -1-seropositive men. Conclusions Circulating concentrations of endothelial-, platelet-, monocyte-, and leukocyte-derived microparticles were higher in antiretroviral therapy-treated HIV -1-seropositive men and adversely affect endothelial cells promoting cellular inflammation, oxidative stress, senescence, and apoptosis. Circulating microparticles may contribute to the vascular risk associated with HIV -1 infection.

Lung Function, Coronary Artery Disease, and Mortality in HIV

Rationale: Impaired lung function is a potent independent predictor of coronary artery disease (CAD) in individuals without human immunodeficiency virus (HIV) infection; however, the relationship between lung function and CAD in HIV remains undefined. Objectives: To examine the relationship between lung function, CAD, mortality, and circulating biomarkers in HIV. Methods: Spirometry, diffusing capacity of the lung for carbon monoxide (DlCO), emphysema, coronary artery calcium, mortality, cause of death, and biomarkers were examined in HIV-infected and uninfected individuals enrolled in a cohort study at the University of Pittsburgh. Results were then validated in the Multicenter AIDS Cohort Study (MACS) cohort. Results: We examined data on 234 participants in the Pittsburgh cohort. The mean ± standard deviation age was 49.5 ± 10.2 years old, 82.1% were male, and 67.5% were ever smokers. Among the 177 of 234 individuals with HIV infection, lower DlCO (not forced expiratory volume in 1 second or emphysema) was independently associated with greater coronary artery calcium (odds ratio, 1.43 per 10% lower DlCO; 95% confidence interval, 1.14-1.81). HIV-infected individuals with both reduced DlCO and coronary artery calcium had a much higher mortality than those with either low DlCO or coronary calcium alone or with neither condition. Endothelin-1, a circulating biomarker of endothelial dysfunction, was associated with both lower DlCO and greater coronary artery calcium in those with HIV infection. Results were reproducible in 144 individuals enrolled in the MACS cohort; intercellular adhesion molecule 1 was the biomarker of endothelial dysfunction assessed in the MACS cohort. Conclusions: Impaired DlCO and CAD were associated with each other and with higher mortality in individuals with HIV infection.

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.

Effects of HIV-1 gp120 and TAT-derived microvesicles on endothelial cell function

The aims of this study were twofold. The first was to determine if human immunodeficiency virus (HIV)-1 glycoprotein (gp) 120 and transactivator of transcription (Tat) stimulate the release of endothelial microvesicles (EMVs). The second was to determine whether viral protein-induced EMVs are deleterious to endothelial cell function (inducing endothelial cell inflammation, oxidative stress, senescence and increasing apoptotic susceptibility). Human aortic endothelial cells (HAECs) were treated with recombinant HIV-1 proteins Bal gp120 (R5), Lav gp120 (X4), or Tat. EMVs released in response to each viral protein were isolated and quantified. Fresh HAECs were treated with EMVs generated under control conditions and from each of the viral protein conditions for 24 h. EMV release was higher (P < 0.05) in HAECs treated with R5 (141 ± 21 MV/µl)_, X4 (132 ± 20 MV/µl), and Tat (130 ± 20 MV/µl) compared with control (61 ± 13 MV/µl). Viral protein EMVs induced significantly higher endothelial cell release of proinflammatory cytokines and expression of cell adhesion molecules than control. Reactive oxygen species production was more pronounced (P < 0.05) in the R5-, X4- and Tat-EMV-treated cells. In addition, viral protein-stimulated EMVs significantly augmented endothelial cell senescence and apoptotic susceptibility. Concomitant with these functional changes, viral protein-stimulated EMVs disrupted cell expression of micro-RNAs 34a, 126, 146a, 181b, 221, and miR-Let-7a (P < 0.05). These results demonstrate that HIV-1 gp120 and Tat stimulate microvesicle release from endothelial cells, and these microvesicles confer pathological effects on endothelial cells by inducing inflammation, oxidative stress, and senescence as well as enhancing susceptibility to apoptosis. Viral protein-generated EMVs may contribute to the increased risk of vascular disease in patients with HIV-1. NEW & NOTEWORTHY Human immunodeficiency virus (HIV)-1-related proteins glycoprotein (gp) 120 and transactivator of transcription (Tat)-mediated endothelial damage and dysfunction are poorly understood. Endothelial microvesicles (EMVs) serve as indicators and potent mediators of endothelial dysfunction. In the present study we determined if HIV-1 R5- and X4-tropic gp120 and Tat stimulate EMV release in vitro and if viral protein-induced EMVs are deleterious to endothelial cell function. gp120 and Tat induced a marked increase in EMV release. Viral protein-induced EMVs significantly increased endothelial cell inflammation, oxidative stress, senescence, and apoptotic susceptibility in vitro. gp120- and Tat-derived EMVs promote a proinflammatory, pro-oxidative, prosenescent, and proapoptotic endothelial phenotype and may contribute to the endothelial damage and dysfunction associated with gp120 and Tat.

Changing concepts of HIV infection and renal disease

PURPOSE OF REVIEW

Human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) was identified as the major renal manifestation of HIV infection early in the HIV epidemic. However, HIV infection now is associated with a different spectrum of renal lesions leading to chronic kidney disease. This review examines the changes in kidney injury occurring in the current HIV era and the factors involved in this transformation of disease expression.

RECENT FINDINGS

The incidence of HIVAN and opportunistic infections in HIV-infected individuals has declined in concert with the use of effective combination antiretroviral agents. Chronic kidney disease has become more prevalent as patients infected with HIV are living longer and developing non-HIV-associated diseases such as hypertension and diabetes. Additionally, noncollapsing focal and segmental glomerulosclerosis, co-infection with hepatitis C, HIV-associated immune complex kidney disease, HIV-related accelerated aging, and antiretroviral therapies contribute to progressive loss of renal function.

SUMMARY

HIV infection is now associated with a variety of renal lesions causing chronic kidney disease, not all of which are virally induced. It is important to determine the cause of renal functional decline in an HIV-infected patient, as this will impact patient management and prognosis.

HIV Proteins and Endothelial Dysfunction: Implications in Cardiovascular Disease

With the success of antiretroviral therapy (ART), a dramatic decrease in viral burden and opportunistic infections and an increase in life expectancy has been observed in human immunodeficiency virus (HIV) infected individuals. However, it is now clear that HIV- infected individuals have enhanced susceptibility to non-AIDS (Acquired immunodeficiency syndrome)-related complications such as cardiovascular disease (CVD). CVDs such as atherosclerosis have become a significant cause of morbidity and mortality in individuals with HIV infection. Though studies indicate that ART itself may increase the risk to develop CVD, recent studies suggest a more important role for HIV infection in contributing to CVD independently of the traditional risk factors. Endothelial dysfunction triggered by HIV infection has been identified as a critical link between infection, inflammation/immune activation, and atherosclerosis. Considering the inability of HIV to actively replicate in endothelial cells, endothelial dysfunction depends on both HIV-encoded proteins as well as inflammatory mediators released in the microenvironment by HIV-infected cells. Indeed, the HIV proteins, gp120 (envelope glycoprotein) and Tat (transactivator of transcription), are actively secreted into the endothelial cell micro-environment during HIV infection, while Nef can be actively transferred onto endothelial cells during HIV infection. These proteins can have significant direct effects on the endothelium. These include a range of responses that contribute to endothelial dysfunction, including enhanced adhesiveness, permeability, cell proliferation, apoptosis, oxidative stress as well as activation of cytokine secretion. This review summarizes the current understanding of the interactions of HIV, specifically its proteins with endothelial cells and its implications in cardiovascular disease. We analyze recent in vitro and in vivo studies examining endothelial dysfunction in response to HIV proteins. Furthermore, we discuss the multiple mechanisms by which these viral proteins damage the vascular endothelium in HIV patients. A better understanding of the molecular mechanisms of HIV protein associated endothelial dysfunction leading to cardiovascular disease is likely to be pivotal in devising new strategies to treat and prevent cardiovascular disease in HIV-infected patients.

Cenicriviroc inhibits trans-endothelial passage of monocytes and is associated with impaired E-selectin expression

Incidences of cardiovascular diseases (CVD) are high among virologically suppressed HIV-infected individuals. Monocyte activation and trafficking are key mechanisms in the evolution of CVD. We studied the ability of cenicriviroc (CVC), a dual C-C chemokine receptor type 2 (CCR2) and CCR5 antagonist, to influence the migration of monocytes from HIV-infected individuals on antiretroviral therapy (ART). Monocytes were derived from 23 ART-suppressed HIV-infected and 16 HIV-uninfected donors. In a trans-endothelial migration model, monocytes, and human aortic endothelial cells (HAoECs) were exposed to cenicriviroc and migrated monocytes, quantified. Expression of CCR2 and CCR5 on monocytes and adhesion molecules (E-selectin, ICAM-1, VCAM-1, PECAM-1, and CD99) on HAoECs were measured. The single antagonists, BMS-22 (CCR2), and maraviroc (CCR5), served as controls. When both HAoECs and monocytes together were exposed to the antagonists, cenicriviroc led to a greater decrease in monocyte migration compared to BMS-22 or vehicle in both HIV-infected and HIV-uninfected groups (P < 0.05), with maraviroc having no inhibitory effect. Cenicriviroc treatment of HAoECs alone decreased monocyte migration in the HIV-infected group when compared to vehicle (P < 0.01). Inhibition of migration was not evident when monocytes alone were exposed to cenicriviroc, BMS-22 or maraviroc. Incubation of HAoECs with cenicriviroc decreased E-selectin expression (P = 0.045) but had limited effects on the other adhesion molecules. Cenicriviroc inhibits monocyte trans-endothelial migration more effectively than single chemokine receptor blockade, which may be mediated via disruption of monocyte-endothelial tethering through reduced E-selectin expression. Cenicriviroc should be considered as a therapeutic intervention to reduce detrimental monocyte trafficking.

Cardiovascular Disease in the Setting of Human Immunodeficiency Virus Infection

Background:

Since the introduction of Antiretroviral Therapy (ART), the life expectancy and health quality for patients infected with Human Immunodeficiency Virus (HIV) have significant-ly improved. Nevertheless, as a result of not only the deleterious effects of the virus itself and pro-longed ART, but also the effects of aging, cardiovascular diseases have emerged as one of the most common causes of death among these patients.

Objective:

The purpose of this review is to explore the new insights on the spectrum of Cardiovascu-lar Disease (CVD) in HIV infection, with emphasis on the factors that contribute to the atherosclerot-ic process and its role in the development of acute coronary syndrome in the setting of infection.

Methods:

A literature search using PubMed, ScienceDirect and Web of Science was performed. Ar-ticles up to Mar, 2017, were selected for inclusion. The search was conducted using MeSH terms, with the following key terms: [human immunodeficiency virus AND (cardiovascular disease OR coronary heart disease) AND (antiretroviral therapy AND (cardiovascular disease OR coronary heart disease))].

Results:

Clinical cardiovascular disease tends to appear approximately 10 years before in infected in-dividuals, when compared to the general population. The pathogenesis behind the cardiovascular, HIV-associated complications is complex and multifactorial, involving traditional CVD risk factors, as well as factors associated with the virus itself - immune activation and chronic inflammation – and the metabolic disorders related to ART regimens.

Conclusion:

Determining the cardiovascular risk among HIV-infected patients, as well as targeting and treating conditions that predispose to CVD, are now emerging concerns among physicians.

miR-34a is a common link in both HIV- and antiretroviral therapy-induced vascular aging

Both HIV and antiretroviral therapy could induce vascular aging with unclear mechanisms. In this study, via microarray analysis, we identified, for the first time, that miR-34a expression was significantly increased in both HIV-infected, and antiretroviral agents-treated vessels and vascular endothelial cells (ECs) from these vessels. In cultured ECs, miR-34a expression was significantly increased by HIV-Tat protein and by the antiretroviral agents, lopinavir/ritonavir. Both HIV-Tat protein and antiretroviral agents could induce EC senescence, which was inhibited by miR-34a inhibition. In contrast, EC senescence was exacerbated by miR-34a overexpression. In addition, the vascular ECs isolated from miR-34a knockout mice were resistant to HIV and antiretroviral agents-mediated senescence. In vivo, miR-34a expression in mouse vascular walls and their ECs was increased by antiretroviral therapy and by HIV-1 Tat transgenic approach. miR-34a inhibition could effectively inhibit both HIV-Tat protein and antiretroviral therapy-induced vascular aging in mice. The increased miR-34a was induced via p53, whereas Sirt1 was a downstream target gene of miR-34a in both HIV-Tat protein and antiretroviral agents-treated ECs and vessels. The study has demonstrated that miR-34a is a common link in both HIV and antiretroviral therapy-mediated vascular aging.

Infectious Agents in Atherosclerotic Cardiovascular Diseases through Oxidative Stress

Accumulating evidence demonstrates that vascular oxidative stress is a critical feature of atherosclerotic process, potentially triggered by several infectious agents that are considered as risk co-factors for the atherosclerotic cardiovascular diseases (CVDs). C. pneumoniae has been shown to upregulate multiple enzymatic systems capable of producing reactive oxygen species (ROS) such as NADPH oxidase (NOX) and cyclooxygenase in vascular endothelial cells, NOX and cytochrome c oxidase in macrophages as well as nitric oxide synthase and lipoxygenase in platelets contributing to both early and late stages of atherosclerosis. P. gingivalis seems to be markedly involved in the atherosclerotic process as compared to A. actinomycetemcomitans contributing to LDL oxidation and foam cell formation. Particularly interesting is the evidence describing the NLRP3 inflammasome activation as a new molecular mechanism underlying P. gingivalis-induced oxidative stress and inflammation. Amongst viral agents, immunodeficiency virus-1 and hepatitis C virus seem to have a major role in promoting ROS production, contributing, hence, to the early stages of atherosclerosis including endothelial dysfunction and LDL oxidation. In conclusion, oxidative mechanisms activated by several infectious agents during the atherosclerotic process underlying CVDs are very complex and not well-known, remaining, thus, an attractive target for future research.

D-Dimer Levels and Traditional Risk Factors Are Associated With Incident Hypertension Among HIV-Infected Individuals Initiating Antiretroviral Therapy in Uganda

OBJECTIVES

We sought to describe blood pressure (BP) changes after antiretroviral therapy (ART) initiation and evaluate the association of markers of inflammation with incident hypertension in a cohort of HIV-infected individuals in Uganda.

METHODS

We used mixed effects linear regression to model changes in systolic BP over time among a cohort of HIV-infected individuals initiating ART in Uganda. After exclusion of participants with preexisting hypertension, we identified participants with normal BP throughout follow-up (controls) and those with elevated BP on ≥3 consecutive visits (cases). Before ART initiation, participants had testing for interleukin 6, kynurenine/tryptophan ratio, lipopolysaccharide, soluble CD14, soluble CD163, and D-dimer and those with viral suppression at 6 months during ART had repeat tests. We fit logistic regression models to estimate associations between biomarkers and risk of incident hypertension.

RESULTS

In the entire cohort, systolic BP increased by 9.6 mm Hg/yr (95% CI: 7.3 to 11.8) in the first 6 months of ART, then plateaued. Traditional factors: male gender (adjusted odds ratio (AOR) 2.76, 95% CI: 1.34 to 5.68), age (AOR 1.09, 95% CI: 1.04 to 1.13), overweight (AOR 4.48, 95% CI: 1.83 to 10.97), and a CD4 count <100 cells (AOR 3.08, 95% CI: 1.07 to 8.89) were associated with incident hypertension. After adjusting for these, D-dimer levels at month 6 were inversely associated with incident hypertension (AOR 0.61, 95% CI: 0.37 to 0.99). Although not significant, similar associations were seen with sCD14 and kynurenine/tryptophan ratio.

CONCLUSION

BP increases early after ART initiation in Ugandans. Traditional risk factors, rather than immune activation, were associated with incident hypertension in this population.

Inflammation-modulating cytokine profile and lipid interaction in HIV-related risk factors for cardiovascular diseases

HIV infection and antiretroviral therapy (ART) are associated with changes in plasma levels of lipoproteins, thus posing the risk of cardiovascular complications in infected individuals. The alteration in plasma lipoprotein levels results from dysregulation of inflammation-modulating cytokines that control lipid metabolism. Little is understood regarding the relationship between the cytokines and serum lipid levels, which have been reported to be altered in adults receiving ART. The objective of this study was to describe the profiles of inflammation-modulating cytokines and their relationship to lipids as cardiovascular disease (CVD) risk factors in HIV infection. This observational cross-sectional study measured plasma levels of interleukin (IL)-10, tumor necrosis factor-alpha (TNF)-α, IL-4, total cholesterol (TC), and high-density lipoprotein cholesterol (HDL-c) in HIV-infected and uninfected adults. A total of 219 HIV-infected participants were enrolled from an HIV treatment center; of them, 187 were receiving ART and 32 were ART naïve, while 65 were HIV-uninfected blood donors. HIV-infected individuals had higher levels of IL-10 (HIV-infected ART-naïve [P=0.0024] and ART-receiving [P=0.033]) than their uninfected counterparts. ART-naïve subjects had significantly higher plasma levels of IL-10 than ART-receiving subjects (P=0.0014). No significant difference was observed in plasma levels of IL-4 and TNF-α across the three groups. Regarding plasma lipoproteins, HDL-c levels were reduced in HIV ART-naïve (P=0.002) and ART-receiving (P=0.015) subjects compared to HIV-uninfected subjects. Similarly, TC levels were lower in the HIV-infected than in the HIV-uninfected group regardless of whether the patients were undergoing ART or not (P<0.001). IL-10 levels correlated with TC levels in the HIV-uninfected group but not in the HIV-infected groups. Levels of HDL-c were reduced, while IL-10 plasma concentrations were elevated in HIV-infected individuals. A correlation observed in HIV-uninfected individuals between anti-inflammatory cytokine IL-10 and TC was lost in HIV-infected individuals. Clinical significance of these differences needs to be ascertained with respect to HIV-related CVD risk.

Inflammatory bowel disease, liver diseases and endothelial function: is there a linkage?

Atherosclerosis is a systemic inflammatory disease able to deeply worsen the outcome of patients because of its serious clinical consequences. The complex inflammatory background underlining such a disease makes atherosclerosis linked to several systemic inflammatory conditions able to impair endothelial function and morphology. Inflammatory bowel diseases are a group of gastrointestinal diseases including Crohn's disease and ulcerative colitis, that is, syndromes characterized by changes in mucosal immunity and gastrointestinal physiology, which could negatively influence the vascular endothelial function and structure. Hepatitis (i.e. inflammatory diseases of the liver mainly due to viral infections) and nonalcoholic fatty liver disease could be aligned to inflammatory bowel disease in such an induction of atherosclerosis disease.Many studies tried to point out the relationship between bowel and liver inflammatory diseases and early vascular changes, considered the first step for atherosclerosis development.The aim of such a narrative review is to explain the relationship between inflammatory bowel disease, hepatitis and nonalcoholic fatty liver disease and their role in increasing cardiovascular risk profile due to early impairment in vascular function and morphology.

Stimulating high impact HIV-related cardiovascular research: recommendations from a multidisciplinary NHLBI Working Group on HIV-related heart, lung, and blood disease

The clinical challenges confronting patients with human immunodeficiency virus (HIV) have shifted from acquired immunodeficiency syndrome (AIDS)-related illnesses to chronic diseases, such as coronary artery disease, chronic lung disease, and chronic anemia. With the growing burden of HIV-related heart, lung, and blood (HLB) disease, the National Heart, Lung, and Blood Institute (NHLBI) recognizes it must stimulate and support HIV-related HLB research. Because HIV offers a natural, accelerated model of common pathological processes, such as inflammation, HIV-related HLB research may yield important breakthroughs for all patients with HLB disease. This paper summarizes the cardiovascular recommendations of an NHLBI Working Group, Advancing HIV/AIDS Research in Heart, Lung, and Blood Diseases, charged with identifying scientific priorities in HIV-related HLB disease and developing recommendations to promote multidisciplinary collaboration among HIV and HLB investigators. The working group included multidisciplinary sessions, as well as HLB breakout sessions for discussion of disease-specific issues, with common themes about scientific priorities and strategies to stimulate HLB research emerging in all 3 groups.

Cardiovascular disease in human immunodeficiency virus

With widespread access to high-quality medical care as in Australia, human immunodeficiency virus (HIV) is now considered a chronic, treatable condition, with a good life expectancy. The use of combined highly active antiretroviral therapy has enabled effective suppression of the virus, but has also been associated with increased cardiac morbidity and mortality. Over representation of traditional cardiac risk factors, such as hyperlipidaemia and diabetes, as well as an increased incidence of ischaemic and non-ischaemic heart disease is now considered a major concern of treatment with antiretroviral therapy. Therefore, a contemporary management strategy for patients with HIV must include active prevention and treatment of cardiovascular risk. This review will outline the complex interplay between HIV infection, antiretroviral drug regimens and accelerated cardiovascular disease, with a particular focus on screening, prevention and treatment options in a contemporary Australian HIV population.

Lipid biology of the podocyte--new perspectives offer new opportunities

In the past 15 years, major advances have been made in understanding the role of lipids in podocyte biology. First, susceptibility to focal segmental glomerulosclerosis (FSGS) and glomerular disease is associated with an APOL1 sequence variant, is expressed in podocytes and encodes apolipoprotein L1, an important component of HDL. Second, acid sphingomyelinase-like phosphodiesterase 3b encoded by SMPDL3b has a role in the conversion of sphingomyelin to ceramide and its levels are reduced in renal biopsy samples from patients with recurrent FSGS. Furthermore, decreased SMPDL3b expression is associated with increased susceptibility of podocytes to injury after exposure to sera from these patients. Third, in many individuals with membranous nephropathy, autoantibodies against the phospholipase A2 (PLA2) receptor, which is expressed in podocytes, have been identified. Whether these autoantibodies affect the activity of PLA2, which liberates arachidonic acid from glycerophospholipids and modulates podocyte function, is unknown. Fourth, clinical and experimental evidence support a role for ATP-binding cassette sub-family A member 1-dependent cholesterol efflux, free fatty acids and glycerophospolipids in the pathogenesis of diabetic kidney disease. An improved understanding of lipid biology in podocytes might provide insights to develop therapeutic targets for primary and secondary glomerulopathies.

Association between short leukocyte telomere length and HIV infection in a cohort study: No evidence of a relationship with antiretroviral therapy

BACKGROUND

Individuals infected with human immunodeficiency virus (HIV) appear to age faster than the general population, possibly related to HIV infection, antiretroviral therapy, and/or social/environmental factors. We evaluated leukocyte telomere length (LTL), a marker of cellular aging, in HIV-infected and uninfected adults.

METHODS

Clinical data and blood were collected from Children and women: AntiRetrovirals and the Mechanism of Aging (CARMA) cohort study participants. Variables found to be important in univariate analysis were multivariate model candidates.

RESULTS

Of the 229 HIV-infected and 166 HIV-uninfected participants, 76% were women, and 71% were current/previous smokers. In a multivariate model of all participants, older age (P < .001), HIV infection (P = .04), active hepatitis C virus (HCV) infection (P = .02), and smoking (P < .003) were associated with shorter LTL. An interaction was detected, whereby smoking was associated with shorter LTL in HIV-uninfected subjects only. Among those, age and smoking (P ≤ .01) were related to shorter LTL. In 2 models of HIV-infected individuals, age (P ≤ .002) and either active HCV infection (P = .05) or peak HIV RNA ≥100 000 copies/mL (P = .04) were associated with shorter LTL, whereas other HIV disease or treatment parameters were unrelated.

CONCLUSIONS

Our results suggest that acquisition of HIV and viral load are primarily responsible for the association between HIV-positive status and shorter LTL. The lack of association between LTL and time since HIV diagnosis, antiretroviral treatment, or degree of immune suppression would implicate HIV infection-related factors rather than disease progression or treatment. Smoking effects on LTL appear masked by HIV, and HCV infection may accelerate LTL shortening, particularly in coinfected individuals. The effect of early therapeutic intervention on LTL in HIV and HCV infections should be evaluated.