Statins demonstrate a broad anti-cytomegalovirus activity in vitro in ganciclovir-susceptible and resistant strains

Validation of nuclear receptor RORγ isoform 1 as a novel host-directed antiviral target based on the modulation of cholesterol levels

Currently, the clinically approved repertoire of antiviral drugs predominantly comprises direct-acting antivirals (DAAs). However, the use of DAAs is frequently limited by adverse effects, restriction to individual virus species, or the induction of viral drug resistance. These issues will likely be resolved by the introduction of host-directed antivirals (HDAs) targeting cellular proteins crucial for viral replication. However, experiences with the development of antiviral HDAs and clinical applications are still in their infancy. With the present study, we explored the human nuclear receptor and transcription factor RORγ isoform 1 (RORγ1), a member of the retinoic acid receptor-related orphan receptor (ROR) family, as a putative target of antiviral HDAs. To this end, cell culture models were used to investigate major viral human pathogens, i.e. the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human cytomegalovirus (HCMV), varicella zoster virus (VZV) and human immunodeficiency virus 1 (HIV-1). Our results demonstrated (i) an antiviral activity of the clinically relevant RORγ modulators cedirogant and others, (ii) that isoform RORγ1 acts as the responsible determinant and drug target in the analyzed cell culture-based models, (iii) a selectivity of the antiviral effect for RORγ1 over related receptors RORα and RORβ, (iv) a late-phase inhibition exerted by cedirogant in HCMV replication and (v) a mechanistic link to the cellular cholesterol biosynthesis. Combined, the data highlight this novel RORγ-specific antiviral targeting concept and the developmental potential of RORγ-directed small molecules.

Effect of atorvastatin on subclinical atherosclerosis in virally-suppressed HIV-infected patients with CMV seropositivity: a randomized double-blind placebo-controlled trial

Background: Persistent immune activation and inflammation in HIV-infection are linked to excess cardiovascular risk and other non-communicable diseases. Periodic asymptomatic CMV-reactivity in HIV infected patients over a lifetime may contribute to non-AIDS defining morbidity. Despite undetectable levels of HIV and CMV, these patients continue to have increased levels of biomarkers and immune activations. Statin administration is thought to reduce subclinical atherosclerosis by decreasing LDL-C levels. It may also add beneficial effects against CMV infection. Methods: We are conducting a double-blind placebo-controlled trial in which patients are randomized to receive either atorvastatin or placebo with a ratio of 1:1. This trial aims to study the effect of atorvastatin in statin-naive virally-suppressed HIV-infected patients with stable ART and CMV seropositivity on carotid intima media thickness (CIMT), tool that evaluates subclinical atherosclerosis. The study recruits 80 patients at HIV integrated care unit of Cipto Mangunkusumo hospital. All eligible subjects have CIMT evaluation as primary outcome, along with flow mediated vasodilatation (FMD), liver fibrosis and steatosis evaluation, fasting lipid, neurocognitive test, community periodontal index (CPI), and residual immune activation as secondary outcomes in 48 weeks. Ethics and dissemination: This study has received an ethical approval from Health Research Ethics Commitee-Universitas Indonesia and Cipto Mangunkusumo Hospital. Before joining the study, all participants fill in an informed consent form. At the end of study analysis, the trial results will be published and disseminated in peer-reviewed journals. Discussion: The main purpose of our study is to evaluate the effect of atorvastatin administration on CIMT changes in statin naïve virally suppressed HIV-infected patients with stable ART and CMV seropositivity Registration: ClinicalTrials.gov ID NCT04101136; registered on 24 September 2019.

Effect of atorvastatin on subclinical atherosclerosis in virally-suppressed HIV-infected patients with CMV seropositivity: a randomized double-blind placebo-controlled trial

Background: Persistent immune activation and inflammation in HIV-infection are linked to excess cardiovascular risk and other non-communicable diseases. Periodic asymptomatic CMV-reactivity in HIV infected patients over a lifetime may contribute to non-AIDS defining morbidity. Despite undetectable levels of HIV and CMV, these patients continue to have increased levels of biomarkers and immune activations. Statin administration is thought to reduce subclinical atherosclerosis by decreasing LDL-C levels. It may also add beneficial effects against CMV infection. Methods: We are conducting a double-blind placebo-controlled trial in which patients are randomized to receive either atorvastatin or placebo with a ratio of 1:1. This trial aims to study the effect of atorvastatin in statin-naive virally-suppressed HIV-infected patients with stable ART and CMV seropositivity on carotid intima media thickness (CIMT), tool that evaluates subclinical atherosclerosis. The study recruits 80 patients at HIV integrated care unit of Cipto Mangunkusumo hospital. All eligible subjects have CIMT evaluation as primary outcome, along with flow mediated vasodilatation (FMD), liver fibrosis and steatosis evaluation, fasting lipid, neurocognitive test, community periodontal index (CPI), and residual immune activation as secondary outcomes in 48 weeks. Ethics and dissemination: This study has received an ethical approval from Health Research Ethics Commitee-Universitas Indonesia and Cipto Mangunkusumo Hospital. Before joining the study, all participants fill in an informed consent form. At the end of study analysis, the trial results will be published and disseminated in peer-reviewed journals. Discussion: The main purpose of our study is to evaluate the effect of atorvastatin administration on CIMT changes in statin naïve virally suppressed HIV-infected patients with stable ART and CMV seropositivity Registration: ClinicalTrials.gov ID NCT04101136; registered on 24 September 2019.

Mutations in AR or SRD5A2 Genes: Clinical Findings, Endocrine Pitfalls, and Genetic Features of Children with 46,XY DSD

OBJECTIVE

Androgen insensivity syndrome (AIS) and 5α-reductase deficiency (5α-RD) present with indistinguishable phenotypes among the 46,XY disorders of sexual development (DSD) that usually necessitate molecular analyses for the definitive diagnosis in the prepubertal period. The aim was to evaluate the clinical, hormonal and genetic findings of 46,XY DSD patients who were diagnosed as AIS or 5α-RD.

METHODS

Patients diagnosed as AIS or 5α-RD according to clinical and hormonal evaluations were investigated. Sequence variants of steroid 5-α-reductase type 2 were analyzed in cases with testosterone/dihydrotestosterone (T/DHT) ratio of ≥20, whereas the androgen receptor (AR) gene was screened when the ratio was <20. Stepwise analysis of other associated genes were screened in cases with no causative variant found in initial analysis. For statistical comparisons, the group was divided into three main groups and subgroups according to their genetic diagnosis and T/DHT ratios.

RESULTS

A total of 128 DSD patients from 125 non-related families were enrolled. Birth weight SDS and gestational weeks were significantly higher in 5α-RD group than in AIS and undiagnosed groups. Completely female phenotype was higher in all subgroups of both AIS and 5α-RD patients than in the undiagnosed subgroups. In those patients with stimulated T/DHT <20 in the prepubertal period, stimulated T/DHT ratio was significantly lower in AIS than in the undiagnosed group, and higher in 5α-RD. Phenotype associated variants were detected in 24% (n=18 AIS, n=14 5α-RD) of the patients, revealing four novel AR variants (c.94G>T, p.Glu32*, c.330G>C, p.Leu110=; c.2084C>T, p.Pro695Leu, c.2585_2592delAGCTCCTG, p.(Lys862Argfs*16), of these c.330G>C with silent status remained undefined in terms of its causative effects.

CONCLUSION

T/DHT ratio is an important hormonal criterion, but in some cases, T/DHT ratio may lead to diagnostic confusion. Molecular diagnosis is important for the robust diagnosis of 46,XY DSD patients. Four novel AR variants were identified in our study.

Low-Density Lipoprotein Receptor Suppresses the Endogenous Cholesterol Synthesis Pathway To Oppose Gammaherpesvirus Replication in Primary Macrophages

Gammaherpesviruses are ubiquitous pathogens that establish lifelong infections in >95% of adults worldwide and are associated with several cancers. We have shown that endogenous cholesterol synthesis supports gammaherpesvirus replication. However, the role of exogenous cholesterol exchange and signaling during infection remains poorly understood. Extracellular cholesterol is carried in the serum by several lipoproteins, including low-density lipoproteins (LDL). The LDL receptor (LDL-R) mediates the endocytosis of these cholesterol-rich LDL particles into the cell, thereby supplying the cell with cholesterol. We found that LDL-R expression attenuates gammaherpesvirus replication during the early stages of the replication cycle, as evident by increased viral gene expression in LDL-R^-/- primary macrophages. This was not observed in primary fibroblasts, indicating that the antiviral effects of LDL-R are cell type specific. Increased viral gene expression in LDL-R^-/- primary macrophages was due to increased activity of the endogenous cholesterol synthesis pathway. Intriguingly, despite type I interferon-driven increase in LDL-R mRNA levels in infected macrophages, protein levels of LDL-R continually decreased over the single cycle of viral replication. Thus, our study has uncovered an intriguing tug of war between the LDL-R-driven antiviral effect on cholesterol metabolism and the viral targeting of the LDL-R protein. IMPORTANCE LDL-R is a cell surface receptor that mediates the endocytosis of cholesterol-rich low-density lipoproteins, allowing cells to acquire cholesterol exogenously. Several RNA viruses usurp LDL-R function to facilitate replication; however, the role of LDL-R in DNA virus infection remains unknown. Gammaherpesviruses are double-stranded DNA viruses that are associated with several cancers. Here, we show that LDL-R attenuates gammaherpesvirus replication in primary macrophages by decreasing endogenous cholesterol synthesis activity, a pathway known to support gammaherpesvirus replication. In response, LDL-R protein levels are decreased in infected cells to mitigate the antiviral effects, revealing an intriguing tug of war between the virus and the host.

Statin exposure and risk of cancer in people with and without HIV infection

OBJECTIVE

To determine whether statin exposure is associated with decreased cancer and mortality risk among persons with HIV (PWH) and uninfected persons. Statins appear to have immunomodulatory and anti-inflammatory effects and may reduce cancer risk, particularly among PWH as they experience chronic inflammation and immune activation.

DESIGN

Propensity score-matched cohort of statin-exposed and unexposed patients from 2002 to 2017 in the Veterans Aging Cohort Study (VACS), a large cohort with cancer registry linkage and detailed pharmacy data.

METHODS

We calculated Cox regression hazard ratios (HRs) and 95% confidence intervals (CI) associated with statin use for all cancers, microbial cancers (associated with bacterial or oncovirus coinfection), nonmicrobial cancers, and mortality.

RESULTS

:The propensity score-matched sample (N = 47 940) included 23 970 statin initiators (31% PWH). Incident cancers were diagnosed in 1160 PWH and 2116 uninfected patients. Death was reported in 1667 (7.0%) statin-exposed, and 2215 (9.2%) unexposed patients. Statin use was associated with 24% decreased risk of microbial-associated cancers (hazard ratio 0.76; 95% CI 0.69-0.85), but was not associated with nonmicrobial cancer risk (hazard ratio 1.00; 95% CI 0.92-1.09). Statin use was associated with 33% lower risk of death overall (hazard ratio 0.67; 95% CI 0.63-0.72). Results were similar in analyses stratified by HIV status, except for non-Hodgkin lymphoma where statin use was associated with reduced risk (hazard ratio 0.56; 95% CI 0.38-0.83) for PWH, but not for uninfected (P interaction = 0.012).

CONCLUSION

In both PWH and uninfected, statin exposure was associated with lower risk of microbial, but not nonmicrobial cancer incidence, and with decreased mortality.

Novel Strategies to Combat CMV-Related Cardiovascular Disease

Cytomegalovirus (CMV), a ubiquitous human pathogen that is never cleared from the host, has long been thought to be relatively innocuous in immunocompetent adults, but causes severe complications including blindness, end-organ disease, and death in newborns and in immuno-compromised individuals, such as organ transplant recipients and those suffering from AIDS. Yet even in persons with intact immunity, CMV infection is associated with profound stimulation of immune and inflammatory pathways. Carriers of CMV infection also have an elevated risk of developing cardiovascular complications. In this review, we define the proposed mechanisms of how CMV contributes to cardiovascular disease (CVD), describe current approaches to target CMV, and discuss how these strategies may or may not alleviate cardiovascular complications in those with CMV infection. In addition, we discuss the special situation of CMV coinfection in people with HIV infection receiving antiretroviral therapy, and describe how these 2 viral infections may interact to potentiate CVD in this especially vulnerable population.

Brief Report: No Evidence for an Association Between Statin Use and Lower Biomarkers of HIV Persistence or Immune Activation/Inflammation During Effective ART

BACKGROUND

Statins exert pleiotropic anti-inflammatory and immune-modulatory effects, which might translate into antiviral activity. We evaluated whether reported current statin exposure is associated with lower levels of markers of HIV persistence and immune activation/inflammation.

METHODS

We compared levels of markers of HIV viral persistence [cell-associated HIV RNA (CA-RNA), CA-DNA, and single copy assay plasma HIV RNA] and immune activation/inflammation (IL-6, IP-10, neopterin, sCD14, sCD163, and TNF-alpha) between statin users and nonusers among participants of ACTG A5321 who initiated antiretroviral therapy (ART) during chronic infection and maintained virologic suppression (HIV-1 RNA levels ≤50 copies/mL) for ≥3 years.

RESULTS

A total of 303 participants were analyzed. Median time on the current statin was 2.9 years (1.2-5.1). There were no differences between statin users and nonusers in levels of CA-DNA (median 650 vs. 540 copies/10 CD4 T cells; P = 0.58), CA-RNA (53 vs. 37 copies/10 CD4 T cells; P = 0.12), or single copy assay (0.4 vs. 0.4 copies/mL; P = 0.45). Similarly, there were no significant differences between statin users and nonusers in markers of inflammation/activation, except for IP-10 (137 vs. 118 pg/mL; P = 0.028). Findings were unchanged after adjustment for factors including pre-ART CD4 and HIV RNA, and years on ART.

CONCLUSIONS

In this cohort of persons on long-term suppressive ART, current statin use was not associated with lower levels of HIV persistence or immune activation/inflammation. These results do not support a major role for statins in reducing HIV persistence, although an early transient effect cannot be excluded. Prospective, randomized studies are needed to confirm these findings.

Viral Induced Oxidative and Inflammatory Response in Alzheimer's Disease Pathogenesis with Identification of Potential Drug Candidates: A Systematic Review using Systems Biology Approach

Alzheimer's disease (AD) is genetically complex with multifactorial etiology. Here, we aim to identify the potential viral pathogens leading to aberrant inflammatory and oxidative stress response in AD along with potential drug candidates using systems biology approach. We retrieved protein interactions of amyloid precursor protein (APP) and tau protein (MAPT) from NCBI and genes for oxidative stress from NetAge, for inflammation from NetAge and InnateDB databases. Genes implicated in aging were retrieved from GenAge database and two GEO expression datasets. These genes were individually used to create protein-protein interaction network using STRING database (score≥0.7). The interactions of candidate genes with known viruses were mapped using virhostnet v2.0 database. Drug molecules targeting candidate genes were retrieved using the Drug- Gene Interaction Database (DGIdb). Data mining resulted in 2095 APP, 116 MAPT, 214 oxidative stress, 1269 inflammatory genes. After STRING PPIN analysis, 404 APP, 109 MAPT, 204 oxidative stress and 1014 inflammation related high confidence proteins were identified. The overlap among all datasets yielded eight common markers (AKT1, GSK3B, APP, APOE, EGFR, PIN1, CASP8 and SNCA). These genes showed association with hepatitis C virus (HCV), Epstein- Barr virus (EBV), human herpes virus 8 and Human papillomavirus (HPV). Further, screening of drugs targeting candidate genes, and possessing anti-inflammatory property, antiviral activity along with a suggested role in AD pathophysiology yielded 12 potential drug candidates. Our study demonstrated the role of viral etiology in AD pathogenesis by elucidating interaction of oxidative stress and inflammation causing candidate genes with common viruses along with the identification of potential AD drug candidates.

Cytomegalovirus Infection in Cardiovascular Diseases

Atherosclerosis underlies the development of many cardiovascular diseases that continue to hold a leading place among the causes of death in developed countries. The role of activated immune cells in atherosclerosis progression has been convincingly demonstrated, but the mechanism of their action remains poorly investigated. Since atherosclerosis is associated with chronic inflammatory response, involvement of viral and bacterial infections in atherogenesis has been examined. A special place among the infectious agents is held by human herpesviruses as the most common persistent viruses in human population coupled to chronic inflammation during atherosclerosis. We found that activation of cytomegalovirus (CMV, human herpesvirus 5) infection is associated with the emergence of acute coronary syndrome, which is in a good agreement with the data on productive CMV infection published elsewhere. In this review, we discuss the data obtained by us and other researchers regarding the role of cytomegalovirus infection and related potential mechanisms resulting in the expansion of atherosclerotic plaques during ischemic heart disease and stroke, including virus transfer to immune and endothelial cells via extracellular vesicles. In particular, the data presented in the review demonstrate that virus spreading in the vascular wall triggers immune system activation in atherosclerotic plaques and causes endothelial dysfunction. Moreover, productive CMV infection in patients with acute myocardial infarction correlates with the extent of endothelial dysfunction. The mechanisms described by us and other researchers may explain the role of CMV infection in atherosclerosis and development of ischemic heart disease.

Potential Effect of Statins on Mycobacterium tuberculosis Infection

Tuberculosis is one of the 10 leading causes of death in the world. The current treatment is based on a combination of antimicrobials administered for six months. It is essential to find therapeutic agents with which the treatment time can be shortened and strengthen the host immune response against Mycobacterium tuberculosis. M. tuberculosis needs cholesterol to infect and survive inside the host, but the progression of the infection depends to a large extent on the capacity of the immune response to contain the infection. Statins inhibit the synthesis of cholesterol and have pleiotropic effects on the immune system, which have been associated with better results in the treatment of several infectious diseases. Recently, it has been reported that cells treated with statins are more resistant to M. tuberculosis infection, and they have even been proposed as adjuvants in the treatment of M. tuberculosis infection. The aim of this review is to summarize the immunopathogenesis of tuberculosis and its mechanisms of evasion and to compile the available scientific information on the effect of statins in the treatment of tuberculosis.

Drug Repurposing for Viral Infectious Diseases: How Far Are We?

Despite the recent advances in controlling some viral pathogens, most viral infections still lack specific treatment. Indeed, the need for effective therapeutic strategies to combat 'old', emergent, and re-emergent viruses is not paralleled by the approval of new antivirals. In the past years, drug repurposing combined with innovative approaches for drug validation, and with appropriate animal models, significantly contributed to the identification of new antiviral molecules and targets for therapeutic intervention. In this review, we describe the main strategies of drug repurposing in antiviral discovery, discuss the most promising candidates that could be repurposed to treat viral infections, and analyze the possible caveats of this trendy strategy of drug discovery.

Cellular Cholesterol Facilitates the Postentry Replication Cycle of Herpes Simplex Virus 1

Cholesterol is an essential component of cell membranes and is required for herpes simplex virus 1 (HSV-1) entry (1-3). Treatment of HSV-1-infected Vero cells with methyl beta-cyclodextrin from 2 to 9 h postentry reduced plaque numbers. Transport of incoming viral capsids to the nuclear periphery was unaffected by the cholesterol reduction, suggesting that cell cholesterol is important for the HSV-1 replicative cycle at a stage(s) beyond entry, after the arrival of capsids at the nucleus. The synthesis and release of infectious HSV-1 and cell-to-cell spread of infection were all impaired in cholesterol-reduced cells. Propagation of HSV-1 on DHCR24-/- fibroblasts, which lack the desmosterol-to-cholesterol conversion enzyme, resulted in the generation of infectious extracellular virions (HSVdes) that lack cholesterol and likely contain desmosterol. The specific infectivities (PFU per viral genome) of HSVchol and HSVdes were similar, suggesting cholesterol and desmosterol in the HSV envelope support similar levels of infectivity. However, infected DHCR24-/- fibroblasts released ∼1 log less infectious HSVdes and ∼1.5 log fewer particles than release of cholesterol-containing particles (HSVchol) from parental fibroblasts, suggesting that the hydrocarbon tail of cholesterol facilitates viral synthesis. Together, the results suggest multiple roles for cholesterol in the HSV-1 replicative cycle.IMPORTANCE HSV-1 infections are associated with a wide range of clinical manifestations that are of public health importance. Cholesterol is a key player in the complex interaction between viral and cellular factors that allows HSV-1 to enter host cells and establish infection. Previous reports have demonstrated a role for cellular cholesterol in the entry of HSV-1 into target cells. Here, we employed both chemical treatment and cells that were genetically defined to synthesize only desmosterol to demonstrate that cholesterol is important at stages following the initial entry and transport of viral capsids to the nucleus. Viral protein expression, encapsidation of the viral genome, and the release of mature virions were impacted by the reduction of cellular cholesterol. Cholesterol was also critical for cell-to-cell spread of infection. These findings provide new insights into the cholesterol dependence of HSV-1 replication.

The association between cytomegalovirus infection, obesity, and metabolic syndrome in U.S. adult females

OBJECTIVE

The purpose of this analysis was to determine whether cytomegalovirus (CMV) infection is associated with the prevalence of metabolic syndrome (MetS) and whether this relationship differs by BMI.

METHODS

Data from the 1999-2004 National Health and Nutrition Examination Survey (NHANES) were pooled (N = 2,532). Logistic regression was used for assessing the association between CMV and MetS, stratified by gender and BMI, categorized as normal weight, overweight, obesity, and extreme obesity, and adjusted for age, race/ethnicity, and poverty level.

RESULTS

In unadjusted analyses, CMV infection was significantly associated with MetS in females (OR: 1.50; 95% CI: 1.1-2.1) but not males. After adjusting for confounders, the odds of MetS were higher in CMV+ normal-weight females (aOR: 65.31; 95% CI: 6.8-625.6) but lower in CMV+ females with extreme obesity (aOR: 0.25; 95% CI: 0.1-0.9). CMV infection was associated with higher high-density lipoprotein cholesterol (HDL-C) and lower triglycerides in females with extreme obesity but lower HDL-C in normal-weight females.

CONCLUSIONS

CMV infection was found to be associated with unique MetS phenotypes that differ between BMI categories and gender. Seropositive normal-weight females had a higher prevalence of MetS and dyslipidemia, while infection in females with extreme obesity was associated with a more metabolically benign profile.

Current use of statins reduces risk of HIV rebound on suppressive HAART

Background

Despite compelling evidence for activity against HIV-1 in vitro, a virologic effect of statins has not been shown in clinical studies. Given their short plasma half-lives, such an effect may be transient and only apparent during ongoing exposure.

Methods

We studied all HIV infected US-Veterans who started HAART 1995–2011, had a documented HIV viral load (VL) >1000 copies/mL, reached an undetectable VL on HAART, and had ≥1 follow-up VL within 13 months. We defined virologic failure (VF) as the first VL >1,000 copies/mL or the first of 2 consecutive VL >200 copies/mL. We built a time-updated drug exposure model for antiretrovirals (ARVs), statins, and other cardiovascular drugs (CVMs), investigating current use (yes/no), recent use (proportion of days used), and categorical use (ever/never). We used both multiply adjusted and inverse-probability-weighted (IPW) Cox models to explore the association between statin and CVM use and VF.

Results

19,324 veterans met inclusion criteria. Median follow-up was 13 months (IQR: 5–32 months); 63% experienced VF after a median time of 9 months (IQR 4–21 months). Almost 1/3 patients ever used statins but exposure comprised only 41% of follow-up time covered after initial prescription. Unadjusted, current statin use was associated with a hazard ratio (HR) for VF of 0.60 (CI: 0.56–0.65). This remained statistically significant after multivariate adjustment (MVA) for demographics, HIV and HAART parameters [HR 0.81 (CI: 0.75–0.88), p<0.001] and IPW (truncation <1%/>99%) HR: 0.83 (CI: 0.75–0.92), p<0.001]. No independent association was observed for other CVMs. The association between categorical-statin use and VF after MVA was much weaker: HR 0.94 (CI: 0.88–1.00, p = 0.04).

Conclusion

Current statin exposure was associated with reduced risk of VF in univariate, multivariate, and inverse-probability-weighted models. Our results highlight the importance of time-updated medication exposure models for observational studies.

Type I Interferon Counteracts Antiviral Effects of Statins in the Context of Gammaherpesvirus Infection

The cholesterol synthesis pathway is a ubiquitous cellular biosynthetic pathway that is attenuated therapeutically by statins. Importantly, type I interferon (IFN), a major antiviral mediator, also depresses the cholesterol synthesis pathway. Here we demonstrate that attenuation of cholesterol synthesis decreases gammaherpesvirus replication in primary macrophages in vitro and reactivation from peritoneal exudate cells in vivo. Specifically, the reduced availability of the intermediates required for protein prenylation was responsible for decreased gammaherpesvirus replication in statin-treated primary macrophages. We also demonstrate that statin treatment of a chronically infected host attenuates gammaherpesvirus latency in a route-of-infection-specific manner. Unexpectedly, we found that the antiviral effects of statins are counteracted by type I IFN. Our studies suggest that type I IFN signaling counteracts the antiviral nature of the subdued cholesterol synthesis pathway and offer a novel insight into the utility of statins as antiviral agents.

IMPORTANCE

Statins are cholesterol synthesis inhibitors that are therapeutically administered to 12.5% of the U.S.

POPULATION

Statins attenuate the replication of diverse viruses in culture; however, this attenuation is not always obvious in an intact animal model. Further, it is not clear whether statins alter parameters of highly prevalent chronic herpesvirus infections. We show that statin treatment attenuated gammaherpesvirus replication in primary immune cells and during chronic infection of an intact host. Further, we demonstrate that type I interferon signaling counteracts the antiviral effects of statins. Considering the fact that type I interferon decreases the activity of the cholesterol synthesis pathway, it is intriguing to speculate that gammaherpesviruses have evolved to usurp the type I interferon pathway to compensate for the decreased cholesterol synthesis activity.

Infection and Stroke: an Update on Recent Progress

The role of infection in cerebrovascular disease is complex and remains incompletely understood. Over the last 5 years, investigators have made notable inroads in untangling this thorny topic. In this review, we examine these recent developments, concentrating on four aspects of the relationship between infection and stroke. We first discuss specific infectious agents as direct causes of stroke, focusing on recent work implicating herpesviruses and HIV in cerebral vasculopathy. We then discuss systemic infection of any type as a stroke trigger, focusing on the relationship of infection to timing of acute stroke, both in children and adults, as well as the role of vaccination in stroke prevention. We examine the evidence for chronic infection or "infectious burden" as a stroke risk factor. Finally, we discuss recent work on infection as a risk factor for increased morbidity after stroke, possible mechanisms mediating this effect, and the evidence for prophylactic antibiotics.

Systematic review of the in vitro effects of statins on oral and perioral microorganisms

Statins are medications administered orally and are widely used for lowering the blood cholesterol level. The aim of this study was to investigate the effects of orally administered statins on microorganisms infecting oral and perioral tissues. We performed a systematic review of published studies of the in vitro antimicrobial effects of statins on bacteria, viruses, and fungi, and searched PubMed, Web of Science, Cochrane Central, and Google scholar. Studies show that most statins exhibit antimicrobial effects against various oral microorganisms. Simvastatin is most effective against the periodontal pathogens Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, and against most dental plaque bacteria, including Streptococcus mutans. Statins also exhibit antiviral properties against human cytomegalovirus, hepatitis B virus, and hepatitis C virus, and have antifungal properties against Candida albicans, Aspergillus fumigatus, and Zygomycetes spp. There were notable differences in the minimum inhibitory concentrations (MICs) between different studies, which may be attributed to differences in study design. Further studies are warranted to ascertain if statins can be solubilized so that patients, who have been prescribed statins for cardiovascular diseases, can use the medication as a swish and swallow, giving patients the added benefit of the antimicrobial action topically in the mouth against infectious oral diseases.

Infection homeostasis: implications for therapeutic and immune programming of metabolism in controlling infection

Homeostasis underpins at a systems level the regulatory control of immunity and metabolism. While physiologically these systems are often viewed as independent, there is increasing evidence showing a tight coupling between immune and metabolic functions. Critically upon infection, the homeostatic regulation for both immune and metabolic pathways is altered yet these changes are often investigated in isolation. Here, we summarise our current understanding of these processes in the context of a clinically relevant pathogen, cytomegalovirus. We synthesise from the literature an integrative view of a coupled immune-metabolic infection process, centred on sugar and lipid metabolism. We put forward the notion that understanding immune control of key metabolic enzymatic steps in infection will promote the future development of novel therapeutic modalities based on metabolic modifiers that either enhance protection or inhibit infection.