Prevention of HIV protease inhibitor-induced dysregulation of hepatic lipid metabolism by raltegravir via endoplasmic reticulum stress signaling pathways

The Impact of Contemporary Antiretroviral Drugs on Atherosclerosis and Its Complications in People Living With HIV: A Systematic Review

With the advent of modern antiretroviral therapy (ART), human immunodeficiency virus (HIV) infection has been modified into a chronic manageable condition, prolonging the lifespan of people living with HIV (PLHIV). This has resulted in an increased non-AIDS-related morbidity in the HIV-infected population. Our aim is to study the role of contemporary ART in tackling the risk of atherosclerosis and cardiovascular disease (CVD) in PLHIV. We searched through the databases of PubMed, PubMed Central, and Cochrane Library for pertinent articles using the medical subject headings (MeSH) "HIV infection", "Atherosclerosis", and "Antiretroviral agents". The articles published in the past five years were retrieved, screened for relevance, and assessed for quality before being included in the review. This review was performed following the PRISMA 2020 guidelines. The results indicate that the incidence of dyslipidemia with integrase strand transfer inhibitors (INSTIs) is greater than with non-nucleoside reverse transcriptase inhibitors (NNRTIs) and lesser than with protease inhibitors (PIs). INSTIs are indispensably associated with weight gain and obesity. High triglyceride (TG) and oxidized low-density lipoproteins to low-density lipoproteins (oxLDL/LDL) ratio levels and low high-density lipoprotein (HDL) levels are seen in patients taking PIs. A higher incidence of hypertension and metabolic syndrome (MetS) was noticed with INSTIs compared to NNRTIs. PI intake for >5 years increases the risk of subclinical atherosclerosis. Increased risk of myocardial infarction with INSTIs was observed in a study, while another study reported decreased risk. HIV infection independently increases the risk for atherosclerosis and CVD. Although contemporary ART decreases this enhanced risk, it inherently increases the risk for abnormal lipid profile, MetS, weight gain, and obesity. Further research into the risk of atherosclerosis and CVD with newer ART drugs is essential for decoding the underlying mechanisms and preventing adverse cardiac outcomes in PLHIV.

SARS-CoV-2-induced liver injury: A review article on the high-risk populations, manifestations, mechanisms, pathological changes, management, and outcomes

The novel coronavirus disease 2019 is an infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and was declared a global pandemic with more than 500 million reported cases and more than 6 million deaths worldwide to date. Although it has transitioned into the endemic phase in many countries, the mortality rate and overall prognosis of the disease are still abysmal and need further improvement. There has been evidence that shows the significance of SARS-CoV-2-related liver injury. Here, we review the literature on the various spectrum of SARS-CoV-2 infection-induced liver injury and the possible mechanisms of damage to the hepatobiliary system. This review aimed to illustrate the latest understanding regarding SARS-CoV-2-induced liver injury including the high-risk populations, the characteristic clinical manifestations, the possible pathogenic mechanism, the pathological changes, the current suggestions for clinical treatment for various spectrum of populations, and the prognosis of the condition. In conclusion, SARS-CoV-2 patients with a liver injury warrant close monitoring as it is associated with the more severe and poorer outcome of the infection.

Transcriptional Effects of Candidate COVID-19 Treatments on Cardiac Myocytes

Introduction

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) has emerged as a major cause of morbidity and mortality worldwide, placing unprecedented pressure on healthcare. Cardiomyopathy is described in patients with severe COVID-19 and increasing evidence suggests that cardiovascular involvement portends a high mortality. To facilitate fast development of antiviral interventions, drugs initially developed to treat other diseases are currently being repurposed as COVID-19 treatments. While it has been shown that SARS-CoV-2 invades cells through the angiotensin-converting enzyme 2 receptor (ACE2), the effect of drugs currently repurposed to treat COVID-19 on the heart requires further investigation.

Methods

Human induced pluripotent stem cell-derived cardiac myocytes (hiPSC-CMs) were treated with five repurposed drugs (remdesivir, lopinavir/ritonavir, lopinavir/ritonavir/interferon beta (INF-β), hydroxychloroquine, and chloroquine) and compared with DMSO controls. Transcriptional profiling was performed to identify global changes in gene expression programs.

Results

RNA sequencing of hiPSC-CMs revealed significant changes in gene programs related to calcium handling and the endoplasmic reticulum stress response, most prominently for lopinavir/ritonavir and lopinavir/ritonavir/interferon-beta. The results of the differential gene expression analysis are available for interactive access at https://covid19drugs.jakobilab.org.

Conclusion

Transcriptional profiling in hiPSC-CMs treated with COVID-19 drugs identified unfavorable changes with lopinavir/ritonavir and lopinavir/ritonavir/INF-β in key cardiac gene programs that may negatively affect heart function.

Liver dysfunction as a cytokine storm manifestation and prognostic factor for severe COVID-19

Liver damage in severe acute respiratory coronavirus 2 infection occurs in patients with or without preexisting liver disorders, posing a significant complication and mortality risk. During coronavirus disease 2019 (COVID-19), abnormal liver function is typically observed. However, liver injury may occur because of the treatment as well. Ischemia, cytokine storm, and hypoxia were identified as the three major factors contributing to liver damage during COVID-19. Indeed, raised liver enzymes during hospitalizations may be attributed to medications used, as well as sepsis and shock. As a result, the proportion of hospitalized patients afflicted with COVID-19 and pathological liver biomarkers varies from 14% to 53%. Aminotransferases and bilirubin are found most often elevated. Usually, increased gamma-glutamyltransferase, alkaline phosphatase, and decreased serum albumin levels are demonstrated. Additionally, although there is no specific treatment for COVID-19, many of the drugs used to treat the infection are hepatotoxic. In this mini-review, we focus on how liver dysfunction can be one of the features associated with the COVID-19 cytokine storm. Furthermore, data show that liver injury can be an independent predictor of severe COVID-19, the need for hospitalization, and death.

Potential Effects of Coronaviruses on the Liver: An Update

The coronaviruses that cause notable diseases, namely, severe acute respiratory syndrome (SARS), middle east respiratory syndrome (MERS) and coronavirus disease 2019 (COVID-19), exhibit remarkable similarities in genomic components and pathogenetic mechanisms. Although coronaviruses have widely been studied as respiratory tract pathogens, their effects on the hepatobiliary system have seldom been reported. Overall, the manifestations of liver injury caused by coronaviruses typically involve decreased albumin and elevated aminotransferase and bilirubin levels. Several pathophysiological hypotheses have been proposed, including direct damage, immune-mediated injury, ischemia and hypoxia, thrombosis and drug hepatotoxicity. The interaction between pre-existing liver disease and coronavirus infection has been illustrated, whereby coronaviruses influence the occurrence, severity, prognosis and treatment of liver diseases. Drugs and vaccines used for treating and preventing coronavirus infection also have hepatotoxicity. Currently, the establishment of optimized therapy for coronavirus infection and liver disease comorbidity is of significance, warranting further safety tests, animal trials and clinical trials.

Gastrointestinal and hepatic diseases during the COVID-19 pandemic: Manifestations, mechanism and management

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is considered the causative pathogen of coronavirus disease 2019 (COVID-19) and has become an international danger to human health. Although respiratory transmission and symptoms are still the essential manifestations of COVID-19, the digestive system could be an unconventional or supplementary route for COVID-19 to be transmitted and manifested, most likely due to the presence of angiotensin-converting enzyme 2 (ACE2) in the gastrointestinal tract. In addition, SARS-CoV-2 can trigger hepatic injury via direct binding to the ACE2 receptor in cholangiocytes, antibody-dependent enhancement of infection, systemic inflammatory response syndrome, inflammatory cytokine storms, ischemia/reperfusion injury, and adverse events of treatment drugs. Gastrointestinal symptoms, including anorexia, nausea, vomiting, and diarrhea, which are unusual in patients with COVID-19, and some digestive signs may occur without other respiratory symptoms. Furthermore, SARS-CoV-2 can be found in infected patients' stool, demonstrating the likelihood of transmission through the fecal-oral route. In addition, liver function should be monitored during COVID-19, particularly in more severe cases. This review summarizes the evidence for extra-pulmonary manifestations, mechanisms, and management of COVID-19, particularly those related to the gastrointestinal tract and liver.

Incidence of dyslipidemia in people with HIV who are treated with integrase inhibitors versus other antiretroviral agents

OBJECTIVE

To compare the incidence of dyslipidemia in people with HIV receiving integrase inhibitors (INSTI) versus boosted protease inhibitors (PI/b) and nonnucleoside reverse transcriptase inhibitors (NNRTI) within RESPOND consortium of prospective cohorts.

METHODS

Participants were eligible if they were at least 18 years, without dyslipidemia and initiated or switched to a three-drug antiretroviral therapy (ART)-regimen consisting of either INSTI, NNRTI, or PI/b for the first time, between 1 January 2012 and 31 December 2018. Dyslipidemia was defined as random total cholesterol more than 240 mg/dl, HDL less than 35 mg/dl, triglyceride more than 200 mg/dl, or initiation of lipid-lowering therapy. Poisson regression was used to determine the adjusted incidence rate ratios. Follow-up was censored after 3 years or upon ART-regimen discontinuation or last lipid measurement or 31 December 2019, whichever occurred first.

RESULTS

Overall, 4577 people with HIV were eligible (INSTI = 66.9%, PI/b = 12.5%, and NNRTI = 20.6%), 1938 (42.3%) of whom were ART-naive. During 1.7 (interquartile range, 0.6-3.0) median years of follow-up, 1460 participants developed dyslipidemia [incidence rate: 191.6 per 1000 person-years, 95% confidence interval (CI) 182.0-201.7]. Participants taking INSTI had a lower incidence of dyslipidemia compared with those on PI/b (adjusted incidence rate ratio 0.71; CI 0.59-0.85), but higher rate compared with those on NNRTI (1.35; CI 1.15-1.58). Compared with dolutegravir, the incidence of dyslipidemia was higher with elvitegravir/cobicistat (1.20; CI 1.00-1.43) and raltegravir (1.24; CI 1.02-1.51), but lower with rilpivirine (0.77; CI 0.63-0.94).

CONCLUSION

In this large consortium of heterogeneous cohorts, dyslipidemia was less common with INSTI than with PI/b. Compared with dolutegravir, dyslipidemia was more common with elvitegravir/cobicistat and raltegravir, but less common with rilpivirine.

Apoptosis of Hepatocytes: Relevance for HIV-Infected Patients under Treatment

Due to medical advances over the past few decades, human immunodeficiency virus (HIV) infection, once a devastatingly mortal pandemic, has become a manageable chronic condition. However, available antiretroviral treatments (cART) cannot fully restore immune health and, consequently, a number of inflammation-associated and/or immunodeficiency complications have manifested themselves in treated HIV-infected patients. Among these chronic, non-AIDS (acquired immune deficiency syndrome)-related conditions, liver disease is one of the deadliest, proving to be fatal for 15–17% of these individuals. Aside from the presence of liver-related comorbidities, including metabolic disturbances and co-infections, HIV itself and the adverse effects of cART are the main factors that contribute to hepatic cell injury, inflammation, and fibrosis. Among the molecular mechanisms that are activated in the liver during HIV infection, apoptotic cell death of hepatocytes stands out as a key pathogenic player. In this review, we will discuss the evidence and potential mechanisms involved in the apoptosis of hepatocytes induced by HIV, HIV-encoded proteins, or cART. Some antiretroviral drugs, especially the older generation, can induce apoptosis of hepatic cells, which occurs through a variety of mechanisms, such as mitochondrial dysfunction, increased production of reactive oxygen species (ROS), and induction of endoplasmic reticulum (ER) stress and unfolded protein response (UPR), all of which ultimately lead to caspase activation and cell death.

The risks of liver injury in COVID-19 patients and pharmacological management to reduce or prevent the damage induced

BACKGROUND

The global pandemic COVID-19 caused by the new coronavirus SARS-CoV-2 has already caused about 1.4 million deaths, and to date, there are no effective or direct antiviral vaccines. Some vaccines are in the last stages of testing. Overall mortality rates vary between countries, for example, from a minimum of 0.05% in Singapore to a maximum of 9.75 in Mexico; however, mortality and severity of COVID-19 are higher in the elderly and in those with comorbidities already present such as diabetes, hypertension, and heart disease.

MAIN TEXT

Recent evidence has shown that an underlying liver disease can also be a risk factor, and SARS-CoV-2 itself can cause direct or indirect damage to liver tissue through multisystem inflammation generated especially in the more severe stages. In the current pandemic, liver dysfunction has been observed in 14-53% of patients with severe COVID-19. In addition, drugs administered during infection may be an additional factor of liver damage. The mechanism of cellular penetration of the virus that occurs by viral entry is through the receptors of the angiotensin 2 conversion enzyme (ACE-2) host that are abundantly present in type II pneumocytes, heart cells, but also liver cholangiocytes.

CONCLUSION

In this manuscript, we describe the clinical management aimed at preserving the liver or reducing the damage caused by COVID-19 and anti-COVID-19 drug treatments.

Hepatic complications of COVID-19 and its treatment

Coronavirus disease 2019 (COVID‐19) is highly contagious and has a variety of clinical manifestations, it can affect a number of other organs in addition to the lungs, and liver injury may occur. Severe acute respiratory syndrome coronavirus 2 can cause liver injury through systemic inflammatory response syndrome, cytokine storms, ischemia‐reperfusion injury, side effects of treatment drugs, and underlying liver disease and can attack liver cells directly via angiotensin‐converting enzyme 2. Clinical studies have found that liver injury in COVID‐19 patients mainly manifests as abnormal liver biochemical indicators, but there have been no reports of liver failure caused by this disease. The number of COVID‐19 patients with liver injury is increasing, and the incidence of liver injury in COVID‐19 patients with severe disease are higher than in patients with mild disease. Liver injury may be a risk factor, which worsens in patients with COVID‐19, and hence it is necessary to pay attention to the occurrence of liver injury in the diagnosis and treatment of COVID‐19.

Liver function impairment may become a predictor of exacerbation and deterioration of patients with COVID‐19.

SARS‐CoV‐2 can cause liver injury through systemic inflammatory response syndrome (SIRS), cytokine storms, ischemia‐reperfusion injury, drugs, underlying liver disease and can attack liver cells directly via ACE2.

It is necessary to pay attention to the occurrence of liver injury in the diagnosis and treatment of COVID‐19.

Raltegravir Attenuates Experimental Pulmonary Fibrosis In Vitro and In Vivo

Raltegravir, an inhibitor of human immunodeficiency virus-1 (HIV-1) integrase, has been used to treat HIV/acquired immunodeficiency syndrome; however, its therapeutic effects on pulmonary fibrosis have not been investigated. In this study, the in vitro effects of raltegravir (RAV) on transforming growth factor beta 1 (TGF-β1)-induced pulmonary fibrosis on L929 mouse fibroblasts were investigated. In addition, the effects of RAV on an in vivo pulmonary fibrosis model induced by intratracheal instillation of bleomycin were investigated. The proliferation of L929 cells was inhibited after RAV treatment. Meanwhile, the in vitro and in vivo protein expression of nucleotide-binding oligomerization domain-like receptor 3 (NLRP3), high-mobility group box 1 (HMGB1), toll-like receptor 4 (TLR4), prolyl hydroxylase domain protein 2, phosphorylated nuclear factor-κB (p-NF-κB), hypoxia-inducible factor-1α (HIF-1α), collagens I and III was reduced relative to TGF-β1 or the bleomycin group. Raltegravir ameliorated pulmonary fibrosis by reducing the pathology score, collagen deposition, and expression of α-smooth muscle actin, NLRP3, HMGB1, TLR4, inhibitor of kappa B, p-NF-κB, HIF-1α, collagen I, and collagen III. The results of this study demonstrate that RAV attenuated experimental attenuates pulmonary fibrosis by inhibiting NLRP3 activation.

Efavirenz and Efavirenz-like Compounds Activate Human, Murine, and Macaque Hepatic IRE1α-XBP1

Efavirenz (EFV), a widely used antiretroviral drug, is associated with idiosyncratic hepatotoxicity and dyslipidemia. Here we demonstrate that EFV stimulates the activation in primary hepatocytes of key cell stress regulators: inositol-requiring 1α (IRE1α) and X-box binding protein 1 (XBP1). Following EFV exposure, XBP1 splicing (indicating activation) was increased 35.7-fold in primary human hepatocytes. In parallel, XBP1 splicing and IRE1α phosphorylation (p-IRE1α, active IRE1α) were elevated 36.4-fold and 4.9-fold, respectively, in primary mouse hepatocytes. Of note, with EFV treatment, 47.2% of mouse hepatocytes were apoptotic; which was decreased to 23.9% in the presence of STF 083010, an inhibitor of XBP1 splicing. Experiments performed using pregnane X receptor (PXR)-null mouse hepatocytes revealed that EFV-mediated XBP1 splicing and hepatocyte death were not dependent on PXR, which is a nuclear receptor transcription factor that plays a crucial role in the cellular response to xenobiotics. Interestingly, incubation with the primary metabolite of EFV, 8-hydroxyefavirenz (8-OHEFV), only resulted in 10.3- and 2.9-fold increased XBP1 splicing in human and mouse hepatocytes and no change in levels of p-IRE1α in mouse hepatocytes. To further probe the structure-activity relationship of IRE1α-XBP1 activation by EFV, 16 EFV analogs were employed. Of these, an analog in which the EFV alkyne is replaced with an alkene and an analog in which the oxazinone oxygen is replaced by a carbon stimulated XBP1 splicing in human, mouse, and macaque hepatocytes. These data demonstrate that EFV and compounds sharing the EFV scaffold can activate IRE1α-XBP1 across human, mouse, and macaque species.

Role of endoplasmic reticulum stress in drug-induced toxicity

Drug‐induced toxicity is a key issue for public health because some side effects can be severe and life‐threatening. These adverse effects can also be a major concern for the pharmaceutical companies since significant toxicity can lead to the interruption of clinical trials, or the withdrawal of the incriminated drugs from the market. Recent studies suggested that endoplasmic reticulum (ER) stress could be an important event involved in drug liability, in addition to other key mechanisms such as mitochondrial dysfunction and oxidative stress. Indeed, drug‐induced ER stress could lead to several deleterious effects within cells and tissues including accumulation of lipids, cell death, cytolysis, and inflammation. After recalling important information regarding drug‐induced adverse reactions and ER stress in diverse pathophysiological situations, this review summarizes the main data pertaining to drug‐induced ER stress and its potential involvement in different adverse effects. Drugs presented in this review are for instance acetaminophen (APAP), arsenic trioxide and other anticancer drugs, diclofenac, and different antiretroviral compounds. We also included data on tunicamycin (an antibiotic not used in human medicine because of its toxicity) and thapsigargin (a toxic compound of the Mediterranean plant Thapsia garganica) since both molecules are commonly used as prototypical toxins to induce ER stress in cellular and animal models.

Increased cardiovascular disease risk in the HIV-positive population on ART: potential role of HIV-Nef and Tat

With effective antiretroviral therapy (ART), many HIV-infected people die of diseases other than acquired immune deficiency syndrome (AIDS). In particular, coronary artery disease has emerged as one of most critical complications of HIV infection and a major cause of morbidity and mortality. Although reportedly antiretroviral combination therapy itself may accelerate atherosclerosis by enhancing dyslipidemia, most recent epidemiological studies support the notion that HIV infection itself contributes to cardiovascular disease. However, it is still a mystery how the virus can contribute to cardiovascular disease development even while suppressed by ARTs. This review discusses the current understanding of interactions between HIV infection and cardiovascular diseases in both clinical and experimental studies with special focus on those viral proteins that are still produced by HIV. This will help infectious disease/vascular biology experts to gain insights into the pathophysiological mechanisms of HIV-associated cardiovascular disease and new trends to treat and prevent cardiovascular disease in the HIV-infected population.

HIV Protease Inhibitors Sensitize Human Head and Neck Squamous Carcinoma Cells to Radiation by Activating Endoplasmic Reticulum Stress

Background

Human head and neck squamous cell carcinoma (HNSCC) is the sixth most malignant cancer worldwide. Despite significant advances in the delivery of treatment and surgical reconstruction, there is no significant improvement of mortality rates for this disease in the past decades. Radiotherapy is the core component of the clinical combinational therapies for HNSCC. However, the tumor cells have a tendency to develop radiation resistance, which is a major barrier to effective treatment. HIV protease inhibitors (HIV PIs) have been reported with radiosensitizing activities in HNSCC cells, but the underlying cellular/molecular mechanisms remain unclear. Our previous study has shown that HIV PIs induce cell apoptosis via activation of endoplasmic reticulum (ER) stress. The aim of this study was to examine the role of ER stress in HIV PI-induced radiosensitivity in human HNSCC.

Methodology and Principal Findings

HNSCC cell lines, SQ20B and FaDu, and the most commonly used HIV PIs, lopinavir and ritonavir (L/R), were used in this study. Clonogenic assay was used to assess the radiosensitivity. Cell viability, apoptosis and cell cycle were analyzed using Cellometer Vision CBA. The mRNA and protein levels of ER stress-related genes (eIF2α, CHOP, ATF-4, and XBP-1), as well as cell cycle related protein, cyclin D1, were detected by real time RT-PCR and Western blot analysis, respectively. The results demonstrated that L/R dose-dependently sensitized HNSCC cells to irradiation and inhibited cell growth. L/R-induced activation of ER stress was correlated to down-regulation of cyclin D1 expression and cell cycle arrest under G0/G1 phase.

Conclusion and Significance

HIV PIs sensitize HNSCC cells to radiotherapy by activation of ER stress and induction of cell cycle arrest. Our results provided evidence that HIV PIs can be potentially used in combination with radiation in the treatment of HNSCC.

Mg supplementation protects against ritonavir-mediated endothelial oxidative stress and hepatic eNOS downregulation

Ritonavir (RTV), a prototypical protease inhibitor currently used as a key component of anti-HIV therapy, is known for its endothelial and hepatic toxicity. The effects of RTV and magnesium supplementation on cultured bovine endothelial cell (EC) and rat hepatic endothelial nitric oxide synthase (eNOS) status were investigated. RTV dose-dependently (5-30 µM) decreased EC viability after 48 h; high Mg (2mM) significantly attenuated the lost viability. ECs incubated with 15 µM RTV for 6 to 24h resulted in two- to fourfold elevation of oxidized glutathione and a 25% loss of total glutathione. At 24h, EC superoxide production due to RTV was detected by dihydroethidium staining and increased 41% when quantified by flow cytometry; altered glutathione status and superoxide levels were both substantially reversed by 2mM Mg. RTV reduced eNOS mRNA (-25% at 24 h) and led to decreased eNOS dimer/monomer ratios; nitric oxide-derived products decreased 40%; both changes were attenuated by Mg supplementation. In male Lewis-Brown Norway rats, RTV administration (75 mg/kg/day, 5 weeks) resulted in an 85% increase in plasma 8-isoprostane and a 23% decrease in hepatic eNOS mRNA; concomitantly, eNOS protein decreased 75%, whereas plasma nitrite level was reduced 48%. Dietary Mg supplementation (sixfold higher than control) prevented the eNOS mRNA decrease along with lowering 8-isoprostane and restored the eNOS protein and plasma nitrite levels comparable to controls. In conclusion, Mg attenuates RTV-mediated EC oxidative eNOS dysfunction and downregulation of hepatic eNOS expression; we suggest that Mg can serve as a beneficial adjunct therapeutic against RTV-mediated eNOS toxicity.

Reduction of the HIV protease inhibitor-induced ER stress and inflammatory response by raltegravir in macrophages

BACKGROUND

HIV protease inhibitor (PI), the core component of highly active antiretroviral treatment (HAART) for HIV infection, has been implicated in HAART-associated cardiovascular complications. Our previous studies have demonstrated that activation of endoplasmic reticulum (ER) stress is linked to HIV PI-induced inflammation and foam cell formation in macrophages. Raltegravir is a first-in-its-class HIV integrase inhibitor, the newest class of anti-HIV agents. We have recently reported that raltegravir has less hepatic toxicity and could prevent HIV PI-induced dysregulation of hepatic lipid metabolism by inhibiting ER stress. However, little information is available as to whether raltegravir would also prevent HIV PI-induced inflammatory response and foam cell formation in macrophages.

METHODOLOGY AND PRINCIPAL FINDINGS

In this study, we examined the effect of raltegravir on ER stress activation and lipid accumulation in cultured mouse macrophages (J774A.1), primary mouse macrophages, and human THP-1-derived macrophages, and further determined whether the combination of raltegravir with existing HIV PIs would potentially exacerbate or prevent the previously observed activation of inflammatory response and foam cell formation. The results indicated that raltegravir did not induce ER stress and inflammatory response in macrophages. Even more interestingly, HIV PI-induced ER stress, oxidative stress, inflammatory response and foam cell formation were significantly reduced by raltegravir. High performance liquid chromatography (HPLC) analysis further demonstrated that raltegravir did not affect the uptake of HIV PIs in macrophages.

CONCLUSION AND SIGNIFICANCE

Raltegravir could prevent HIV PI-induced inflammatory response and foam cell formation by inhibiting ER stress. These results suggest that incorporation of this HIV integrase inhibitor may reduce the cardiovascular complications associated with current HAART.

Comparative analysis of ER stress response into HIV protease inhibitors: lopinavir but not darunavir induces potent ER stress response via ROS/JNK pathway

HIV protease inhibitor (PI)-induced ER stress has been associated with adverse effects. Although it is a serious clinical problem for HIV/AIDS patients, comparative analyses of ER stress induction by clinically used PIs have rarely been done. Especially, there is no report on the differential ER stress response between lopinavir (LPV) and darunavir (DRV), although these PIs are the most clinically used PIs. We show here that LPV induces the most potent CHOP expression, ER stress marker, among the 9 Food and Drug Administration (FDA)-approved PIs in human peripheral blood mononuclear cells, several human epithelial cells, and mouse embryonic fibroblasts. LPV induced the most potent ROS production and JNK activation in 9 PIs. A comparison among the most clinically used PIs, ritonavir (RTV), LPV, and DRV, revealed that LPV potently and RTV moderately but not DRV induced ER stress via ROS-dependent JNK activation rather than proteasome inhibition. Finally, we analyzed ER stress induction in tissues of mice intraperitoneally injected with RTV, LPV, and DRV. RTV and LPV but not DRV showed ER stress induction in several mice tissues. In conclusion, we first identify LPV as the most potent ER stress inducing PI among 9 FDA-approved PIs in human cells, and although clinical verification is necessary, we show here that DRV has the advantage of less ROS and ER stress induction potential compared with LPV in vitro and in vivo.

Anti-retroviral drugs do not facilitate hepatitis C virus (HCV) infection in vitro

An estimated 4 to 5 million people are co-infected with HIV/HCV worldwide. Recently observed outbreaks of acute HCV infection among HIV-positive men who have sex with men (MSM) have been linked to behavioral factors such as high risk sexual practices and recreational drug use. However, at the molecular level, many drugs such as glucocorticoids or cyclosporine A have been found to modulate viral replication. Thus, it is conceivable that drugs used in highly active antiretroviral therapy (HAART) may heighten susceptibility to HCV infection and contribute to the recent outbreaks. We therefore performed a comprehensive screen of antiretroviral drugs covering all available drug classes both individually and in typical combinations used during HAART to probe for direct effects on HCV cell entry, replication, new particle assembly and release. Importantly, no significant enhancement or inhibition of HCV cell entry, replication or new particle production was detected. While raltegravir and ritonavir boosted atazanavir reduce HCV replication, a tenfold reduction of HCVcc entry by the CCR5 antagonist maraviroc was observed. In conclusion, commonly used HAART agents do not specifically enhance HCV replication. Thus recent epidemic outbreaks of acute HCV in HIV-infected MSM are unlikely to be related to enhancing effects of HAART drugs.