HIV-related cardiovascular disease and drug interactions

A smart nanosensor for the detection of human immunodeficiency virus and associated cardiovascular and arthritis diseases using functionalized graphene-based transistors

Human immunodeficiency virus (HIV), which isa worldwide public health issue, is commonly associated with cardiovascular disorders (CVDs) and rheumatoid arthritis (RA). A smart nanosensor was developed for the detection of HIV and its related diseases (CVDs and RA) using graphene-based field-effect transistors (FETs). In this study, amine-functionalized graphene (afG) was conjugated with antibodies [anti-p24 for HIV, anti-cardiac troponin 1 (anti-cTn1) for CVDs, and anti-cyclic citrullinated peptide (anti-CCP) for RA] to detect various biomarkers. The antibodies were covalently conjugated to afG via carbodiimide activation. The bioconjugate (graphene-antibody) was characterized by various biophysical techniques such as UV-Vis, Raman spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). The electrochemical performance of the sensor was evaluated with respect to changes in the resistance of the electrode surface due to the interaction of the antigen with its specific antibody. The developed sensor was highly sensitive and showed a linear response to p24, cTn1, and, CCP from 1 fg/mL to 1 μg/mL. The limit of detection (LOD) was 100 fg/mL for p24 and 10 fg/mL for cTn1 and CCP under standard optimized conditions. The graphene-based smart nanodevice demonstrated excellent performance; thus, it could be used for the on-site detection of HIV, CVD, and RA biomarkers in real samples.

Development of GLUT4-selective antagonists for multiple myeloma therapy

Cancer cells consume more glucose to fuel metabolic programs fundamental to sustaining their survival, growth and proliferation. Among the fourteen SLC2A family members, GLUTs 1 and 4 are high-affinity glucose transporters. GLUT4 (SLC2A4) is highly expressed in muscle and adipose tissue. Basally retained within the cell, GLUT4 traffics to the plasma membrane (PM) in response to insulin and exercise-stimulation. The plasma cell malignancy multiple myeloma (MM) exhibits increased constitutive expression of GLUT4 on the PM, co-opting use of GLUT4 for survival and proliferation. GLUT4 inhibition by knockdown or treatment with the FDA-approved HIV protease inhibitor ritonavir leads to cytostatic and/or cytotoxic and chemosensitizing effects in tumor cells both in vitro and in vivo. We recently reported our generation of GLUT4 homology models and virtual high-throughput screening (vHTS) to identify multiple series of novel GLUT4 antagonists. In this report, we describe our initial hit-to-lead optimization to synthesize new analogs with improved potency and selectivity for GLUT4, and the biological characterization of these compounds in a variety of assays. We show that our lead compound (compound 20) decreases glucose uptake and cell proliferation as well as inhibits the expression of pro-survival MCL-1 in MM similar to the effect observed via knockdown of GLUT4 expression. Compound 20 is also effective at chemosensitizing multiple myeloma cell lines and patient samples to venetoclax, dexamethasone and melphalan. In sum, we report development of selective GLUT4 inhibitors lacking inhibitory activity against GLUT1 and GLUT8. We show that selective pharmacological inhibition of GLUT4 is feasible and this may represent a novel strategy for the treatment and chemosensitization of multiple myeloma to standard therapeutics.

HIV DNA Is Frequently Present within Pathologic Tissues Evaluated at Autopsy from Combined Antiretroviral Therapy-Treated Patients with Undetectable Viral Loads

HIV infection treatment strategies have historically defined effectiveness through measuring patient plasma HIV RNA. While combined antiretroviral therapy (cART) can reduce plasma viral load (pVL) to undetectable levels, the degree that HIV is eliminated from other anatomical sites remains unclear. We investigated the HIV DNA levels in 229 varied autopsy tissues from 20 HIV-positive (HIV(+)) cART-treated study participants with low or undetectable plasma VL and cerebrospinal fluid (CSF) VL prior to death who were enrolled in the National Neurological AIDS Bank (NNAB) longitudinal study and autopsy cohort. Extensive medical histories were obtained for each participant. Autopsy specimens, including at least six brain and nonbrain tissues per participant, were reviewed by study pathologists. HIV DNA, measured in tissues by quantitative and droplet digital PCR, was identified in 48/87 brain tissues and 82/142 nonbrain tissues at levels >200 HIV copies/million cell equivalents. No participant was found to be completely free of tissue HIV. Parallel sequencing studies from some tissues recovered intact HIV DNA and RNA. Abnormal histological findings were identified in all participants, especially in brain, spleen, lung, lymph node, liver, aorta, and kidney. All brain tissues demonstrated some degree of pathology. Ninety-five percent of participants had some degree of atherosclerosis, and 75% of participants died with cancer. This study assists in characterizing the anatomical locations of HIV, in particular, macrophage-rich tissues, such as the central nervous system (CNS) and testis. Additional studies are needed to determine if the HIV recovered from tissues promotes the pathogenesis of inflammatory diseases, such as HIV-associated neurocognitive disorders, cancer, and atherosclerosis.

IMPORTANCE

It is well-known that combined antiretroviral therapy (cART) can reduce plasma HIV to undetectable levels; however, cART cannot completely clear HIV infection. An ongoing question is, "Where is HIV hiding?" A well-studied HIV reservoir is "resting" T cells, which can be isolated from blood products and succumb to cART once activated. Less-studied reservoirs are anatomical tissue samples, which have unknown cART penetration, contain a comparably diverse spectrum of potentially HIV-infected immune cells, and are important since <2% of body lymphocytes actually reside in blood. We examined 229 varied autopsy specimens from 20 HIV(+) participants who died while on cART and identified that >50% of tissues were HIV infected. Additionally, we identified considerable pathology in participants' tissues, especially in brain, spleen, lung, lymph node, liver, aorta, and kidney. This study substantiates that tissue-associated HIV is present despite cART and can inform future studies into HIV persistence.

Possible Biomarkers for the Early Detection of HIV-associated Heart Diseases: A Proteomics and Bioinformatics Prediction

The frequency of cardiovascular disorders is increasing in HIV-infected individuals despite a significant reduction in the viral load by antiretroviral therapies (ART). Since the CD4 + T-cells are responsible for the viral load as well as immunological responses, we hypothesized that chronic HIV-infection of T-cells produces novel proteins/enzymes that cause cardiac dysfunctions. To identify specific factors that might cause cardiac disorders without the influence of numerous cofactors produced by other pathogenic microorganisms that co-inhabit most HIV-infected individuals, we analyzed genome-wide proteomes of a CD4 + T-cell line at different stages of HIV replication and cell growth over > 6 months. Subtractive analyses of several hundred differentially regulated proteins from HIV-infected and uninfected counterpart cells and comparisons with proteins expressed from the same cells after treating with the antiviral drug Zidovudine/AZT and inhibiting virus replication, identified a well-coordinated network of 12 soluble/diffusible proteins in HIV-infected cells. Functional categorization, bioinformatics and statistical analyses of each protein predicted that the expression of cardiac-specific Ca2 + kinase together with multiple Ca2 + release channels causes a sustained overload of Ca2 + in the heart which induces fetal/cardiac myosin heavy chains (MYH6 and MYH7) and a myosin light-chain kinase. Each of these proteins has been shown to cause cardiac stress, arrhythmia, hypertrophic signaling, cardiomyopathy and heart failure (p = 8 × 10^− 11). Translational studies using the newly discovered proteins produced by HIV infection alone would provide additional biomarkers that could be added to the conventional markers for an early diagnosis and/or development of specific therapeutic interventions for heart diseases in HIV-infected individuals.

Assessment of cardiac function with Doppler tissue imaging in asymptomatic HIV-infected patients

Doppler tissue imaging (DTI) is a useful tool for the detection of subtle systolic function abnormalities related to the longitudinal contraction. We assessed left ventricular (LV) systolic function with DTI in 45 human immunodeficiency virus (HIV)-infected patients without any heart-related symptoms and in 30 healthy control subjects. Although conventional echocardiography showed no differences between groups, DTI revealed lower peak systolic velocities in group A patients when compared with group B ones (Sms: 8.84 ± 0.94 cm/s vs. 9.42 ± 0.84 cm/s, respectively, P < 0.001 and Sml: 9.58 ± 1.86 cm/s vs. 10.78 ± 2.07 cm/s P = 0.003). In group A patients, both peak systolic myocardial velocities at the septal (Sms) and lateral mitral annulus (Sml) correlated with CD4 lymphocyte count (P = 0.034 and 0.009, respectively). We conclude that pulse wave DTI reveals subtle and non-otherwise detectable abnormalities of the longitudinal LV contractile function in asymptomatic patients with positive HIV serology. DTI study should potentially be expanded in the population of HIV-infected patients, aiming at an early identification of LV systolic dysfunction.

HIV protease inhibitors that block GLUT4 precipitate acute, decompensated heart failure in a mouse model of dilated cardiomyopathy

The clinical use of HIV protease inhibitors is associated with insulin resistance and other metabolic changes that increase long-term cardiovascular risk. Since the failing heart has increased reliance on glucose, the influence of drug exposure on glucose homeostasis, myocardial glucose uptake, cardiac function, and survival was determined in TG9 mice, an established transgenic model of dilated cardiomyopathy generated by cardiac-specific overexpression of Cre-recombinase, as these animals progressed to overt heart failure. Beginning on day of life 75, TG9 mice and nontransgenic littermate controls were given a daily 10 mg/kg intraperitoneal injection of HIV protease inhibitors (ritonavir, lopinavir/ritonavir 4:1, atazanavir, atazanavir/ritonavir 4:1) or vehicle. Glucose tolerance testing, measurement of in vivo myocardial 2-deoxyglucose uptake, and echocardiography were performed before and 30 min following drug administration. The progression of dilated cardiomyopathy in TG9 animals was accompanied by impaired glucose tolerance, which was acutely exacerbated by exposure to ritonavir. Ritonavir and lopinavir precipitated acute, decompensated heart failure and death from pulmonary edema in TG9 mice. However, atazanavir, which does not inhibit glucose transport, had no effect. These studies demonstrate that, in the presence of dilated cardiomyopathy, HIV protease inhibitors that impair glucose transport induce acute, decompensated heart failure. The potential for HIV protease inhibitors to contribute to or exacerbate cardiomyopathy in human patients warrants further investigation.

QT prolongation and Torsades de Pointes in patients previously treated with anthracyclines

Anthracyclines reduce myocardial repolarization reserve and might increase the risk for Torsades de Pointes a long time after treatment. We studied all the publications concerning Torsades de Pointes in patients previously treated with anthracyclines to investigate the clinical circumstances leading to this rare life-threatening complication. Our literature search yielded nine reports of 11 patients who had developed Torsades de Pointes anywhere from weeks to years following treatment with anthracyclines. One of the patients was hospitalized in our medical center. Risk factors and triggers for Torsades de Pointes, among other clinical aspects, were analyzed in each report. Most patients (n=10; 90.9%) were previously treated with anthracyclines owing to acute leukemias: acute myelogenous leukemia (n=5), acute lymphocytic leukemia (n=3) and acute promyelocytic leukemia (n=2). One patient was previously treated with anthracyclines owing to Hodgkin's lymphoma. Most patients were women (n=9; 81.8%). The most prevalent triggers for Torsades de Pointes were the administration of a QT-prolonging agent (n=10; 90.9%) and hypokalemia (n=9; 81.8%). Azole derivatives were the most prevalent of the QT-prolonging agents that triggered Torsades de Pointes (n=5; 45.5%). Although four patients suffered from anthracycline-induced left ventricular dysfunction and five other patients had only one or two questionable triggers for Torsades de Pointes, in only two of these cases the authors considered previous treatment with anthracyclines as a risk factor for Torsades de Pointes. Previous treatment with anthracycline is an underestimated risk factor for Torsades de Pointes. Possible triggers includes azole derivatives, other QT-prolonging agents and hypokalemia. Women patients are particularly at risk.

Physical activity in a cohort of HIV-positive and HIV-negative injection drug users

Physical activity is beneficial for persons with HIV infection but little is known about the relationships between physical activity, HIV treatment and injection drug use (IDU). This study compared physical activity levels between HIV-negative and HIV-positive injection drug users (IDUs) and between HIV-positive participants not on any treatment and participants on highly active antiretroviral therapy (HAART). Anthropometric measurements were obtained and an interviewer-administered modified Paffenbarger physical activity questionnaire was administered to 324 participants in a sub-study of the AIDS Linked to Intravenous Experiences (ALIVE) cohort, an ongoing study of HIV-negative and HIV-positive IDUs. Generalized linear models were used to obtain univariate means and to adjust for confounding (age, gender, employment and recent IDU). Vigorous activity was lower among HAART participants than HIV-positive participants not on treatment (p=0.0025) and somewhat lower than HIV-negative participants (p=0.11). Injection drug use and viral load were not associated with vigorous activity. Energy expenditure in vigorous activity was also lower among HAART participants than both HIV-negative and HIV-positive participants not on treatment. Thus, HIV-positive participants on HAART spend less time on vigorous activity independent of recent IDU. More research is needed into the reasons and mechanism for the lack of vigorous activities, including behavioral, psychological and physiological reasons.

Torsade de pointes induced by systemic antifungal agents: lessons from a retrospective analysis of published case reports

Torsade de pointes (TdP) is a potentially fatal arrhythmia that might be associated with systemic antifungal agent (SAFAs) administration. The objective of this study was to investigate all published reports on TdP induced by SAFAs in order to characterise this association. Each original report was analysed for the presence of risk factors for TdP: female gender, structural heart disease, electrolyte imbalance, concomitant use of a QT interval prolonging agent which SAFA inhibits its liver metabolism, liver cirrhosis, renal failure and more. Naranjo probability scale for adverse drug reactions was applied for every full report. Twenty-one reports on 28 patients were analysed. All patients survived. Most patients (25/28; 89.2%) used one or more agents that might have prolonged the QT interval and their liver metabolism might have been inhibited by SAFA. Female gender was the second most common risk factor for TdP (20/28; 71.4%). All patients, including female patients, had one or more risk factors for TdP prior to SAFA administration. According to Narajno probability scale, there was no definite association between TdP and SAFA in any report. SAFA alone might seldom trigger TdP. We wish to raise the level of awareness of risk factors for TdP prior to SAFA administration and for concomitant use of other dysrhythmogenic agents in particular.

Methadone-associated Torsades de Pointes (polymorphic ventricular tachycardia) in opioid-dependent patients

AIMS

We reviewed all the publications concerning methadone-associated Torsades de Pointes (TdP) (polymorphic ventricular tachycardia) in opioid-dependent patients in order to characterize the clinical circumstances leading to this serious complication.

METHODS

Our literature search yielded 14 reports on 40 patients with methadone-associated TdP. We gathered and recorded the risk factors for TdP mentioned in those reports, among other clinical aspects.

RESULTS

The most prevalent risk factors for TdP were high-dose methadone (n = 39, 97.5%) and concomitant use of agents that increase serum methadone levels or trigger TdP (n = 22, 55%). HIV infection (n = 16), hypokalaemia (n = 14), female sex (n = 13), liver cirrhosis or renal failure (n = 11) and heart disease (n = 9) were also described. All the patients had at least one and 34 (85%) had two or more risk factors for TdP during methadone treatment.

CONCLUSIONS

We wish to raise the level of awareness of risk factors for TdP among physicians in heroin-treatment clinics who frequently prescribe methadone.

HAART to heart: HIV-related cardiomyopathy and other cardiovascular complications

More than one million Americans have been diagnosed with human immunodeficiency virus (HIV). Advances in prevention and treatment of HIV have led to an increased life expectancy for patients with HIV infection. Due to their increased life span, HIV+ patients are now presenting to hospitals with an increased number of diverse late-stage complications, such as cardiomyopathy and other cardiovascular conditions. These complications are as a direct or indirect result of HIV disease, HIV treatment modalities, comorbid conditions, dietary and lifestyle factors, and unknown etiologies. Cardiac complications, particularly HIV-related dilated cardiomyopathy, are potentially life-threatening diagnoses, with symptoms that may be minimized with appropriate cardiac-specific assessments and treatments, patient teaching, and collaboration among nurses caring for the HIV-positive client with cardiac disease.

Sustained improvement of dyslipidaemia in HAART-treated patients replacing stavudine with tenofovir

OBJECTIVE

To describe the 12-month evolution of lipid profile in HIV-infected virologically suppressed patients substituting tenofovir for stavudine.

DESIGN AND METHODS

'Recover' was a prospective, multicenter, switch study conducted at 120 HIV units across Spain designed to identify single nucleoside analogue substitution due to adverse events in real practice. Tenofovir substituted stavudine in 873 adult patients. No other substitutions were allowed. This lipid sub-study included 352 randomly recruited patients with complete follow-up and lipid parameters.

MAIN OUTCOME MEASURES

Changes in fasting levels of total cholesterol (TC), high and low-density lipoprotein cholesterol (HDL-C and LDL-C), and triglycerides (TG) at 48 weeks, and their cardiovascular risk (CVR) translation.

RESULTS

At 48 weeks, there was a sustained reduction in median TC (-17.5 mg/dl; P < 0.001), LDL-C (-8.1 mg/dl; P < 0.001), and TG (-35 mg/dl; P < 0.001). HDL-C remained roughly unchanged (-0.8 mg/dl). Patients with baseline hyperlipidaemia showed greater reductions in LDL-C (-29 mg/dl; P < 0.001) and TG (-76 mg/dl; P < 0.001). The greatest TG reduction was observed in patients with severe hyper-TG (-266 mg/dl; P < 0.001). The estimated 10-year CVR decreased in all patients (P < 0.001), and to a higher extent in patients with baseline hyperlipidaemia. There was a trend towards reduction according to the use of lipid-lowering agents (11.6% to 9,9%; P = non-significant).

CONCLUSIONS

The substitution of tenofovir for stavudine causes a sustained improvement of dyslipidaemia. The reduction, although modest, is robust and sustained over time, and significantly reduces the CVR. This switch strategy is safe and contributes to an improvement in the lipid profile, especially TG, in HAART-treated patients.

Impact of HIV and highly active antiretroviral therapy on leukocyte adhesion molecules, arterial inflammation, dyslipidemia, and atherosclerosis

Highly active antiretroviral therapy (HAART) has greatly extended the lives of people infected with the human immunodeficiency virus (HIV). This reduced risk of early death from opportunistic infections or other sequelae of HIV infection, however, means that other possible causes of death emerge. Myocardial infarction has become a matter of particular concern. Two of the main sources of cardiovascular disease in this population are believed to be vascular inflammation and dyslipidemia. We review the evidence for this hypothesis and discuss the relationship of HIV to vascular inflammation. Current treatment guidelines do not recommend the immediate initiation of HAART unless warranted, potentially allowing long-term, unchecked viral impact on the development of atherosclerosis. Finally, we consider the protease inhibitors traditionally included in HAART regimens and their relationship to the development of dyslipidemia, as well as other classes of antiretrovirals, such as the non-nucleoside reverse transcriptase inhibitors, which might be a better choice for patients with cardiovascular risks. Other strategies, such as pharmacologic, nutritional, and physical activity interventions are discussed. The patients who might benefit most are those in whom the precursors of vascular plaques, such as fatty streak, smooth muscle cell, macrophage, and T-lymphocyte aggregation not yet identified by echocardiographic and biopsy findings have already developed as a result of unchecked viral inflammation and replication.