Atorvastatin attenuates myocardial remodeling induced by chronic intermittent hypoxia in rats: partly involvement of TLR-4/MYD88 pathway

Statin Therapy, Inflammation, and Outcomes in Patients Hospitalized for COVID-19: A Prospective Multicenter Cohort Study

BACKGROUND

Statins are lipid-lowering agents with anti-inflammatory effects. Data surrounding the benefits of statins in patients with coronavirus disease 2019 (COVID-19) are conflicting. We sought to better understand the impact of statins in the context of COVID-19-related inflammation.

METHODS

We leveraged the International Study of Inflammation in COVID-19, a prospective multicenter cohort of patients hospitalized for COVID-19 between February 2020 and October 2022. Participants underwent systematic assessment of biomarkers of inflammation. We used logistic regression modeling and inverse probability-of-treatment weighting (IPTW) to examine the association between prior statin use and the composite outcome of in-hospital death, need for mechanical ventilation, and need for renal replacement therapy.

RESULTS

A total of 4464 patients were included in the study, of whom 1364 (27.5%) were taking a statin prior to admission. There were 1061 primary outcome events, including 540 deaths, 854 mechanical ventilation and 313 renal replacement therapy. Amongst biomarkers of inflammation, statin use was associated solely with lower levels of soluble urokinase plasminogen activator receptor (suPAR) after adjusting for known confounders. In multivariable logistic regression analysis, statin use was associated with lower odds of the composite outcome (adjusted odds ratio (aOR) 0.63, 95% CI [0.53-0.76]) compared to patients not on statins. Findings were consistent with IPTW (aOR 0.92, 95% CI [0.89- 0.95]). The proportion of the effect of statin on the primary outcome mediated by suPAR was estimated at 31.5%.

CONCLUSION

Prior-statin use is associated with improved outcomes and lower inflammation as measured by suPAR levels in patients hospitalized for COVID-19.

Unveiling the Mechanism of Protective Effects of Tanshinone as a New Fighter Against Cardiovascular Diseases: A Systematic Review

Tanshinone, a natural compound found in the roots of Salvia miltiorrhiza, has been shown to possess various pharmacological properties, including anti-inflammatory, antioxidant, and cardiovascular protective effects. This article aims to review the literature on the cardiovascular protective effects of tanshinone and its underlying mechanisms. Tanshinone has been demonstrated to improve cardiac function, reduce oxidative stress, and inhibit inflammation in various animal models of cardiovascular diseases. Additionally, it has been shown to regulate multiple signaling pathways involved in the pathogenesis of cardiovascular diseases, such as the PI3K/AKT, MAPK, and NF-κB pathways. Clinical studies have also suggested that tanshinone may have therapeutic potential for treating cardiovascular diseases. In conclusion, tanshinone has emerged as a promising natural compound with significant cardiovascular protective effects, and further research is warranted to explore its potential clinical applications.

Melatonin effects on oxidative stress and on TLR4/NF-kβ inflammatory pathway in the right ventricle of rats with pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterised by an increase in mean pulmonary arterial pressure and a compromised the right ventricle (RV), together with progression to heart failure and premature death. Studies have evaluated the role of melatonin as a promising therapeutic strategy for PAH. The objective of this study was to evaluate melatonin's effects on oxidative stress and on the TLR4/NF-kβ inflammatory pathway in the RV of rats with PAH. Male Wistar rats were divided into the following groups: control, monocrotaline (MCT), and monocrotaline plus melatonin groups. These two last groups received one intraperitoneal injection of MCT (60 mg/kg) on the first day of experimental protocol. The monocrotaline plus melatonin group received 10 mg/kg/day of melatonin by gavage for 21 days. Echocardiographic analysis was performed, and the RV was collected for morphometric analysis oxidative stress and molecular evaluations. The main findings of the present study were that melatonin administration attenuated the reduction in RV function that was induced by monocrotaline, as assessed by TAPSE. In addition, melatonin prevented RV diastolic area reduction caused by PAH. Furthermore, animals treated with melatonin did not show an increase in ROS levels or in NF-kβ expression. In addition, the monocrotaline plus melatonin group showed a reduction in TLR4 expression when compared with control and monocrotaline groups. To our knowledge, this is the first study demonstrating a positive effect of melatonin on the TLR4/NF-kβ pathway in the RV of rats with PAH. In this sense, this study makes it possible to think of melatonin as a possible ally in mitigating RV alterations caused by PAH.

Obstructive Sleep Apnea-Associated Intermittent Hypoxia-Induced Immune Responses in Males, Pregnancies, and Offspring

Obstructive sleep apnea (OSA), a respiratory sleep disorder associated with cardiovascular diseases, is more prevalent in men. However, OSA occurrence in pregnant women rises to a level comparable to men during late gestation, creating persistent effects on both maternal and offspring health. The exact mechanisms behind OSA-induced cardiovascular diseases remain unclear, but inflammation and oxidative stress play a key role. Animal models using intermittent hypoxia (IH), a hallmark of OSA, reveal several pro-inflammatory signaling pathways at play in males, such as TLR4/MyD88/NF-κB/MAPK, miRNA/NLRP3, and COX signaling, along with shifts in immune cell populations and function. Limited evidence suggests similarities in pregnancies and offspring. In addition, suppressing these inflammatory molecules ameliorates IH-induced inflammation and tissue injury, providing new potential targets to treat OSA-associated cardiovascular diseases. This review will focus on the inflammatory mechanisms linking IH to cardiovascular dysfunction in males, pregnancies, and their offspring. The goal is to inspire further investigations into the understudied populations of pregnant females and their offspring, which ultimately uncover underlying mechanisms and therapeutic interventions for OSA-associated diseases.

Chronic intermittent hypoxia-induced cardiovascular and renal dysfunction: from adaptation to maladaptation

Chronic intermittent hypoxia (CIH) is the dominant pathological feature of human obstructive sleep apnoea (OSA), which is highly prevalent and associated with cardiovascular and renal diseases. CIH causes hypertension, centred on sympathetic nervous overactivity, which persists following removal of the CIH stimulus. Molecular mechanisms contributing to CIH-induced hypertension have been carefully delineated. However, there is a dearth of knowledge on the efficacy of interventions to ameliorate high blood pressure in established disease. CIH causes endothelial dysfunction, aberrant structural remodelling of vessels and accelerates atherosclerotic processes. Pro-inflammatory and pro-oxidant pathways converge on disrupted nitric oxide signalling driving vascular dysfunction. In addition, CIH has adverse effects on the myocardium, manifesting atrial fibrillation, and cardiac remodelling progressing to contractile dysfunction. Sympatho-vagal imbalance, oxidative stress, inflammation, dysregulated HIF-1α transcriptional responses and resultant pro-apoptotic ER stress, calcium dysregulation, and mitochondrial dysfunction conspire to drive myocardial injury and failure. CIH elaborates direct and indirect effects in the kidney that initially contribute to the development of hypertension and later to chronic kidney disease. CIH-induced morphological damage of the kidney is dependent on TLR4/NF-κB/NLRP3/caspase-1 inflammasome activation and associated pyroptosis. Emerging potential therapies related to the gut-kidney axis and blockade of aryl hydrocarbon receptors (AhR) are promising. Cardiorenal outcomes in response to intermittent hypoxia present along a continuum from adaptation to maladaptation and are dependent on the intensity and duration of exposure to intermittent hypoxia. This heterogeneity of OSA is relevant to therapeutic treatment options and we argue the need for better stratification of OSA phenotypes.

Toll-like receptors in cardiac hypertrophy

Toll-like receptors (TLRs) are a family of pattern recognition receptors (PRRs) that can identify pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). TLRs play an important role in the innate immune response, leading to acute and chronic inflammation. Cardiac hypertrophy, an important cardiac remodeling phenotype during cardiovascular disease, contributes to the development of heart failure. In previous decades, many studies have reported that TLR-mediated inflammation was involved in the induction of myocardium hypertrophic remodeling, suggesting that targeting TLR signaling might be an effective strategy against pathological cardiac hypertrophy. Thus, it is necessary to study the mechanisms underlying TLR functions in cardiac hypertrophy. In this review, we summarized key findings of TLR signaling in cardiac hypertrophy.

Inappropriate Activation of TLR4/NF-κB is a Cause of Heart Failure

Significance: Heart failure, a disease with extremely high incidence, is closely associated with inflammation and oxidative stress. The Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) pathway plays an important role in the occurrence and development of heart failure.

Recent advances: Previous studies have shown that TLR4/NF-κB causes heart failure by inducing oxidative stress and inflammation; damaging the endothelia; promoting fibrosis; and inducing myocardial hypertrophy, apoptosis, pyroptosis, and autophagy.

Critical issues: Understanding the pathogenesis of heart failure is essential for the treatment of this disease. In this review, we outline the mechanisms underlying TLR4/NF-κB pathway-mediated heart failure and discuss drugs that alleviate heart failure by regulating the TLR4/NF-κB pathway.

Future directions: During TLR4/NF-κB overactivation, interventions targeting specific receptor antagonists may effectively alleviate heart failure, thus providing a basis for the development of new anti-heart failure drugs.

Protective effects of statins on COVID-19 risk, severity and fatal outcome: a nationwide Swedish cohort study

The impact of statins on COVID-19 remains unclear. This study aims to investigate whether statin exposure assessed both in the population and in well-defined cohorts of COVID-19 patients may affect the risk and severity of COVID-19 using nationwide Swedish population-based register data. A population ≥ 40 years was selected by age/sex-stratified random sampling from the Swedish population on 1 Jan 2020. COVID-19 outcomes were identified from the SmiNet database, the National Patient Register and/or Cause-of-Death Register and linked with the National Prescribed Drug Register and sociodemographic registers. Statin exposure was defined as any statin prescriptions in the year before index date. In Cox regressions, confounding was addressed using propensity score ATT (Average Treatment effect in the Treated) weighting. Of 572,695 individuals in the overall cohort, 22.3% had prior statin treatment. After ATT weighting, protective effects were observed among statin user for hospitalization and COVID-19 death in the overall cohort and onset cohort. In the hospitalized cohort, statin use was only associated with lower risk for death (HR = 0.86, 95% CI 0.79–0.95), but not ICU admission. Statin-treated individuals appear to have lower COVID-19 mortality than nonusers, whether assessed in the general population, from COVID-19 onset or from hospitalization.

Statin and aspirin as adjuvant therapy in hospitalised patients with SARS-CoV-2 infection: a randomised clinical trial (RESIST trial)

Background

Statins and aspirin have been proposed for treatment of COVID-19 because of their anti-inflammatory and anti-thrombotic properties. Several observational studies have shown favourable results. There is a need for a randomised controlled trial.

Methods

In this single-center, open-label, randomised controlled trial, 900 RT-PCR positive COVID-19 patients requiring hospitalisation, were randomly assigned to receive either atorvastatin 40 mg (Group A, n = 224), aspirin 75 mg (Group B, n = 225), or both (Group C, n = 225) in addition to standard of care for 10 days or until discharge whichever was earlier or only standard of care (Group D, n = 226). The primary outcome variable was clinical deterioration to WHO Ordinal Scale for Clinical Improvement ≥ 6. The secondary outcome was change in serum C-reactive protein, interleukin-6, and troponin I.

Results

The primary outcome occurred in 25 (2.8%) patients: 7 (3.2%) in Group A, 3 (1.4%) in Group B, 8 (3.6%) in Group C, and 7 (3.2%) in Group D. There was no difference in primary outcome across the study groups (P = 0.463). Comparison of all patients who received atorvastatin or aspirin with the control group (Group D) also did not show any benefit [Atorvastatin: HR 1.0 (95% CI 0.41–2.46) P = 0.99; Aspirin: HR 0.7 (95% CI 0.27–1.81) P = 0.46]. The secondary outcomes revealed lower serum interleukin-6 levels among patients in Groups B and C. There was no excess of adverse events.

Conclusions

Among patients admitted with mild to moderate COVID-19 infection, additional treatment with aspirin, atorvastatin, or a combination of the two does not prevent clinical deterioration.

Trial Registry Number CTRI/2020/07/026791 (http://ctri.nic.in; registered on 25/07/2020)

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07570-5.

Role of statins in regulating molecular pathways following traumatic brain injury: A system pharmacology study

Traumatic brain injury (TBI) is a serious disorder with debilitating physical and psychological complications. Previous studies have indicated that genetic factors have a critical role in modulating the secondary phase of injury in TBI. Statins have interesting pleiotropic properties such as antiapoptotic, antioxidative, and anti-inflammatory effects, which make them a suitable class of drugs for repurposing in TBI. In this study, we aimed to explore how statins modulate proteins and pathways involved in TBI using system pharmacology. We first explored the target associations with statins in two databases to discover critical clustering groups, candidate hub and critical hub genes in the network of TBI, and the possible connections of statins with TBI-related genes. Our results showed 1763 genes associated with TBI. Subsequently, the analysis of centralities in the PPI network displayed 55 candidate hub genes and 15 hub genes. Besides, MCODE analysis based on threshold score:10 determined four modular clusters. Intersection analysis of genes related to TBI and statins demonstrated 204 shared proteins, which suggested that statins influence 31 candidate hub and 9 hub genes. Moreover, statins had the highest interaction with MCODE1. The biological processes of the 31 shared proteins are related to gene expression, inflammation, antioxidant activity, and cell proliferation. Biological enriched pathways showed Programmed Cell Death proteins, AGE-RAGE signaling pathway, C-type lectin receptor signalling pathway, and MAPK signaling pathway as top clusters. In conclusion, statins could target several critical post-TBI genes mainly involved in inflammation and apoptosis, supporting the previous research results as a potential therapeutic agent.

Cardioprotective Antioxidant and Anti-Inflammatory Mechanisms Induced by Intermittent Hypobaric Hypoxia

More than 80 million people live and work (in a chronic or intermittent form) above 2500 masl, and 35 million live in the Andean Mountains. Furthermore, in Chile, it is estimated that 100,000 people work in high-altitude shifts, where stays in the lowlands are interspersed with working visits in the highlands. Acute exposure to high altitude has been shown to induce oxidative stress in healthy human lowlanders due to increased free radical formation and decreased antioxidant capacity. However, intermittent hypoxia (IH) induces preconditioning in animal models, generating cardioprotection. Here, we aim to describe the responses of a cardiac function to four cycles of intermittent hypobaric hypoxia (IHH) in a rat model. The twelve adult Wistar rats were randomly divided into two equal groups, a four-cycle of IHH and a normobaric hypoxic control. Intermittent hypoxia was induced in a hypobaric chamber in four continuous cycles (1 cycle = 4 days of hypoxia + 4 days of normoxia), reaching a barometric pressure equivalent to 4600 m of altitude (428 Torr). At the end of the fourth cycle, cardiac structural and functional variables were also determined by echocardiography; furthermore, cardiac oxidative stress biomarkers (4-Hydroxynonenal, HNE; nitrotyrosine, NT), antioxidant enzymes, and NLRP3 inflammasome panel expression are also determined. Our results show a higher ejection and a shortening fraction of the left ventricle function by the end of the fourth cycle. Furthermore, cardiac tissue presented a decreased expression of antioxidant proteins. However, a decrease in IL-1β, TNF-αn, and oxidative stress markers is observed in IHH compared to normobaric hypoxic controls. Non-significant differences were found in protein levels of NLRP3 and caspase-1. IHH exposure determines structural and functional heart changes. These findings suggest that initial states of IHH are beneficial for cardiovascular function and protection.

Immunomodulatory agents for COVID-19 treatment: possible mechanism of action and immunopathology features

The novel coronavirus pandemic has emerged as one of the significant medical-health challenges of the current century. The World Health Organization has named this new virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the first detection of SARS-CoV-2 in November 2019 in Wuhan, China, physicians, researchers, and others have made it their top priority to find drugs and cures that can effectively treat patients and reduce mortality rates. The symptoms of Coronavirus Disease 2019 (COVID-19) include fever, dry cough, body aches, and anosmia. Various therapeutic compounds have been investigated and applied to mitigate the symptoms in COVID-19 patients and cure the disease. Degenerative virus analyses of the infection incidence and COVID-19 have demonstrated that SARS-CoV-2 penetrates the pulmonary alveoli's endothelial cells through Angiotensin-Converting Enzyme 2 (ACE2) receptors on the membrane, stimulates various signaling pathways and causes excessive secretion of cytokines. The continuous triggering of the innate and acquired immune system, as well as the overproduction of pro-inflammatory factors, cause a severe condition in the COVID-19 patients, which is called "cytokine storm". It can lead to acute respiratory distress syndrome (ARDS) in critical patients. Severe and critical COVID-19 cases demand oxygen therapy and mechanical ventilator support. Various drugs, including immunomodulatory and immunosuppressive agents (e.g., monoclonal antibodies (mAbs) and interleukin antagonists) have been utilized in clinical trials. However, the studies and clinical trials have documented diverging findings, which seem to be due to the differences in these drugs' possible mechanisms of action. These drugs' mechanism of action generally includes suppressing or modulating the immune system, preventing the development of cytokine storm via various signaling pathways, and enhancing the blood vessels' diameter in the lungs. In this review article, multiple medications from different drug families are discussed, and their possible mechanisms of action are also described.

Genetic Predisposition and Inflammatory Inhibitors in COVID-19: Where Do We Stand?

Severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2) and the resulting coronavirus disease-19 (COVID-19) have led to a global pandemic associated with high fatality rates. COVID-19 primarily manifests in the respiratory system as an acute respiratory distress syndrome following viral entry through the angiotensin-converting enzyme-2 (ACE2) that is present in pulmonary epithelial cells. Central in COVID-19 is the burst of cytokines, known as a “cytokine storm”, and the subsequent widespread endothelial activation, leading to cardiovascular complications such as myocarditis, arrhythmias, and adverse vascular events, among others. Genetic alterations may play an additive, detrimental role in the clinical course of patients with COVID-19, since gene alterations concerning ACE2, major histocompatibility complex class I, and toll-like receptors may predispose patients to a worse clinical outcome. Since the role of inflammation is quintessential in COVID-19, pharmacologic inhibition of various signaling pathways such as the interleukin-1 and -6, tumor necrosis factor-alpha, interferon gamma, Janus kinase-signal transducer and activator of transcription, and granulocyte–macrophage colony-stimulating factor may ameliorate the prognosis following timely administration. Finally, frequently used, non-specific anti-inflammatory agents such as corticosteroids, statins, colchicine, and macrolides represent additional therapeutic considerations.

COVID-19, the Pandemic of the Century and Its Impact on Cardiovascular Diseases

COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely ranks among the deadliest diseases in human history. As with other coronaviruses, SARS-CoV-2 infection damages not only the lungs but also the heart and many other organs that express angiotensin-converting enzyme 2 (ACE2), a receptor for SARS-CoV-2. COVID-19 has upended lives worldwide. Dietary behaviors have been altered such that they favor metabolic and cardiovascular complications, while patients have avoided hospital visits because of limited resources and the fear of infection, thereby increasing out-hospital mortality due to delayed diagnosis and treatment. Clinical observations show that sex, age, and race all influence the risk for SARS-CoV-2 infection, as do hypertension, obesity, and pre-existing cardiovascular conditions. Many hospitalized COVID-19 patients suffer cardiac injury, acute coronary syndromes, or cardiac arrhythmia. SARS-CoV-2 infection may lead to cardiomyocyte apoptosis and necrosis, endothelial cell damage and dysfunction, oxidative stress and reactive oxygen species production, vasoconstriction, fibrotic and thrombotic protein expression, vascular permeability and microvascular dysfunction, heart inflammatory cell accumulation and activation, and a cytokine storm. Current data indicate that COVID-19 patients with cardiovascular diseases should not discontinue many existing cardiovascular therapies such as ACE inhibitors, angiotensin receptor blockers, steroids, aspirin, statins, and PCSK9 inhibitors. This review aims to furnish a framework relating to COVID-19 and cardiovascular pathophysiology.

MyD88: At the heart of inflammatory signaling and cardiovascular disease

Cardiovascular disease is a leading cause of death worldwide and is associated with systemic inflammation. In depth study of the cell-specific signaling mechanisms mediating the inflammatory response is vital to improving anti-inflammatory therapies that reduce mortality and morbidity. Cellular damage in the cardiovascular system results in the release of damage associated molecular patterns (DAMPs), also known as "alarmins," which activate myeloid cells through the adaptor protein myeloid differentiation primary response 88 (MyD88). MyD88 is broadly expressed in most cell types of the immune and cardiovascular systems, and its role often differs in a cardiovascular disease context and cell specific manner. Herein we review what is known about MyD88 in the setting of a variety of cardiovascular diseases, discussing cell specific functions and the relative contributions of MyD88-dependent vs. independent alarmin triggered inflammatory signaling. The widespread involvement of these pathways in cardiovascular disease, and their largely unexplored complexity, sets the stage for future in depth mechanistic studies that may place MyD88 in both immune and non-immune cell types as an attractive target for therapeutic intervention in cardiovascular disease.

Relationship between Innate Immune Response Toll-Like Receptor 4 (TLR-4) and the Pathophysiological Process of Obesity Cardiomyopathy

Fundamento

A obesidade é uma condição inflamatória crônica de baixo grau relacionada a distúrbios cardíacos. No entanto, o mecanismo responsável pela inflamação cardíaca relacionada à obesidade não é claro. O receptor do tipo toll 4 (TLR-4) pertence a um receptor da família das transmembranas, responsável pela resposta imune, cuja ativação estimula a produção de citocinas pró-inflamatórias.

Objetivo

Testar se a ativação do receptor TLR-4 participa do processo de cardiomiopatia da obesidade, devido à produção de citocinas por meio da ativação do NF-ĸB.

Métodos

Ratos Wistar machos foram randomizados em dois grupos: o grupo controle (C, n = 8 animais) que recebeu dieta padrão/água e o grupo obeso (OB, n = 8 animais) que foi alimentado com dieta rica em açúcar e gordura e água mais 25% de sacarose por 30 semanas. Análise nutricional: peso corporal, índice de adiposidade, alimentos, água e ingestão calórica. Análise de distúrbios relacionados à obesidade: glicose plasmática, ácido úrico e triglicerídeos, HOMA-IR, pressão arterial sistólica, TNF-α no tecido adiposo. A análise cardíaca incluiu: expressão das proteínas TLR-4 e NF-ĸB, níveis de TNF-α e IL-6. Comparação pelo teste t de Student não pareado ou teste de Mann-Whitney com um valor de p <0,05 como estatisticamente significativo.

Resultados

O grupo OB apresentou obesidade, glicose elevada, triglicerídeos, ácido úrico, HOMA, pressão arterial sistólica e TNF-α no tecido adiposo. O grupo OB apresentou remodelação cardíaca e disfunção diastólica. A expressão de TLR-4 e NF-ĸB e os níveis de citocinas foram maiores em OB.

Conclusão

Nossos achados concluem que, em uma condição obesogênica, a inflamação derivada da ativação do TLR-4 cardíaco pode ser um mecanismo capaz de levar à remodelação e disfunção cardíaca.

Atorvastatin attenuates intermittent hypoxia-induced myocardial oxidative stress in a mouse obstructive sleep apnea model

Chronic intermittent hypoxia (CIH), a hallmark of obstructive sleep apnea (OSA), is associated with various cardiovascular diseases. In the present study, we assessed the effect of the lipid reducing agent atorvastatin on CIH-induced myocardial oxidative stress and apoptosis in a mouse OSA model. Forty-eight C57BL/6J mice were evenly divided among normoxia + vehicle, normoxia + atorvastatin, CIH + vehicle, and CIH + atorvastatin groups. CIH consisted of a hypoxia-reoxygenation cycle in which oxygen concentrations fluctuated from 21% to 6% and back over two minutes for 8 hours each day (30 events/hour). CIH exposure continued for 12 weeks. Atorvastatin (5 mg/kg) was administered from week 6 through the end of the experiment. CIH increased malondialdehyde levels and decreased superoxide dismutase activity, total antioxidant capacity, and nuclear factor erythroid 2-related factor 2 levels in cardiac tissue, indicating a reduction in antioxidant activity. Atorvastatin significantly reversed those effects (p < 0.05). CIH also increased B-cell lymphoma 2-associated protein X and cleaved caspased-3 levels as well as the myocardial apoptotic rate, as indicated by terminal deoxynucleotidyl transferase dUTP nick-end labeling. Atorvastatin had no effect on those changes (p > 0.05). Thus, atorvastatin administration exerts antioxidant but not anti-apoptotic effects after CIH and may therefore have therapeutic potential in OSA patients with cardiovascular comorbidities.

Gastrodin Exerts Cardioprotective Action via Inhibition of Insulin-Like Growth Factor Type 2/Insulin-Like Growth Factor Type 2 Receptor Expression in Cardiac Hypertrophy

Pathological cardiac hypertrophy is commonly associated with an upregulation of fetal genes, fibrosis, cardiac dysfunction, and heart failure. Previous studies have demonstrated that gastrodin (GAS) exerts cardioprotective action in the treatment of cardiac hypertrophy. However, the mechanism by which GAS protects against cardiac hypertrophy is yet to be elucidated. A mouse model of myocardial hypertrophy was established using an angiotensin II (Ang II) induction. GAS (5 or 50 mg/kg/d) was orally administered every day starting 7 days prior to the Ang II infusion combined with sham-operated controls. Heart samples from each group were collected for RNA sequencing. Using bioinformatics analysis, the key differentially expressed genes (DEGs) that are involved in reversing cardiac function were identified. Through bioinformatics analysis, the key DEGs that are involved in GAS's inhibition of Ang II-induced abnormal gene expression within the heart were identified. This was further validated using quantitative real-time PCR and Western blotting in neonatal rat cardiomyocytes (NRCMs). Oral administration of GAS significantly suppressed the Ang II-induced increase in heart size and heart weight to body weight. Furthermore, pretreatment of the NRCMs with GAS led to a dose-dependent inhibition of Ang II-induced increases in Nppb mRNA expression. We identified 620 upregulated and 87 downregulated Ang II-induced DEGs II, among which the expression patterns of 58 and 146 genes were inverted by low-dose and high-dose GAS, respectively. These inverted DEGs were found to be mainly enriched in the biological processes of regulation of Ras protein signal transduction, heart contraction, covalent chromatin modification, glucose metabolism, and positive regulation of cell cycle. Among them, the insulin-like growth factor type 2 (Igf2) gene, which was found to be highly reversed and downregulated by GAS, served as a core gene linking energy metabolism, immune regulation, and systemic development. Subsequent functional verification demonstrated that IGF2, and its receptor IGF2R, is one of the targets of GAS that helps protect against cardiac hypertrophy. Taken together, we have identified, for the first time, IGF2/IGF2R as a potential target influenced by GAS in the prevention of cardiac hypertrophy.

Statin use and mortality in COVID-19 patients: Updated systematic review and meta-analysis

BACKGROUND AND AIMS

Statin therapy is administered to patients with high cardiovascular risk. These patients are also at risk for severe course of coronavirus disease 2019 (COVID-19). Statins exhibit not only cardioprotective but also immunomodulatory and anti-inflammatory effects. This study performed a systematic review of published evidence regarding statin treatment and COVID-19 related mortality.

METHODS

A systematic PubMed/Embase search was performed from February 10, 2020 until March 05, 2021 for studies in COVID-19 patients that reported adjusted hazard or odds ratio for death in statin users versus non-users.

RESULTS

22 studies fulfilled the inclusion criteria and were included in the systematic review. Meta-analysis of 10 studies (n = 41,807, weighted age 56 ± 8 years, men 51%, hypertension 34%, diabetes 21%, statin users 14%) that reported adjusted hazard ratios for mortality in statin users versus non-users showed pooled estimate at 0.65 (95% confidence intervals [CI] 0.53, 0.81). Meta-analysis of 6 studies that reported continuation of statin therapy during hospitalization (58-100% of patients) revealed a pooled hazard ratio of 0.54 (95% CI 0.47, 0.62). Meta-analysis of 12 studies (n = 72,881, weighted age 65 ± 2 years, men 54%, hypertension 66%, diabetes 43%, statin users 30%) that reported adjusted odds ratios for mortality showed pooled estimate at 0.65 (95% CI 0.55, 0.78). Multivariable meta-regression analysis did not reveal any significant association of hazard or odds ratios with anthropometric characteristics or comorbidities.

CONCLUSIONS

This meta-analysis of retrospective observational studies showed that statin therapy was associated with an about 35% decrease in the adjusted risk of mortality in hospitalized COVID-19 patients.

Studying the Effect of Taking Statins before Infection in the Severity Reduction of COVID-19 with Machine Learning

Statins can help COVID-19 patients' treatment because of their involvement in angiotensin-converting enzyme-2. The main objective of this study is to evaluate the impact of statins on COVID-19 severity for people who have been taking statins before COVID-19 infection. The examined research patients include people that had taken three types of statins consisting of Atorvastatin, Simvastatin, and Rosuvastatin. The case study includes 561 patients admitted to the Razi Hospital in Ghaemshahr, Iran, during February and March 2020. The illness severity was encoded based on the respiratory rate, oxygen saturation, systolic pressure, and diastolic pressure in five categories: mild, medium, severe, critical, and death. Since 69.23% of participants were in mild severity condition, the results showed the positive effect of Simvastatin on COVID-19 severity for people that take Simvastatin before being infected by the COVID-19 virus. Also, systolic pressure for this case study is 137.31, which is higher than that of the total patients. Another result of this study is that Simvastatin takers have an average of 95.77 mmHg O₂Sat; however, the O₂Sat is 92.42, which is medium severity for evaluating the entire case study. In the rest of this paper, we used machine learning approaches to diagnose COVID-19 patients' severity based on clinical features. Results indicated that the decision tree method could predict patients' illness severity with 87.9% accuracy. Other methods, including the K-nearest neighbors (KNN) algorithm, support vector machine (SVM), Naïve Bayes classifier, and discriminant analysis, showed accuracy levels of 80%, 68.8%, 61.1%, and 85.1%, respectively.

Nicorandil inhibits TLR4/MyD88/NF-κB/NLRP3 signaling pathway to reduce pyroptosis in rats with myocardial infarction

Pyroptosis is an inflammatory cell death that regulates cardiomyocyte loss after myocardial infarction. Reports indicate that nicorandil has a strong anti-inflammatory effect and protects the myocardium from myocardial infarction. However, its relationship with pyroptosis is largely unreported. Here, we investigated to influence and mechanism of action of nicorandil on cardiomyocyte pyroptosis. Forty Sprague Dawley rats were randomly assigned to sham, MI, MI + nicorandil, and MI + nicorandil + TAK242 groups (10 per group). Myocardial infarction modeling was performed through ligation of the anterior descending branch of the left coronary artery. The function of cardiac was evaluated through echocardiography, detection of myocardial adenine nucleotides, cTnI, LDH, TTC, and HE staining. Moreover, we used qRT-PCR, immunohistochemistry, and Western blotting to examine the expression of pyroptosis-related molecules and the inflammasome pathway of TLR4/MyD88/NF-κB/NLRP3. Myocardial infarction caused the activation of GSDMD, aggravated myocardial injury, and triggered cardiac dysfunction. Myocardial infarction induced pyroptotic cell death, manifested as upregulation in mRNA and protein levels associated with pyroptosis, including caspase-1 cleavage and increased expression of IL-1β and IL-18. These changes were mitigated by nicorandil. The achieved data implicate that myocardial infarction induces pyroptosis via the TLR4/MyD88/NF-κB/NLRP3 pathway, which can be inhibited by nicorandil pretreatment. Therefore, nicorandil exerts cardioprotective effects by activating K_ATP channels, and at least in part through inhibition of the TLR4/MyD88/NF-κB/NLRP3 pathway to reduce myocardial infarction-induced pyroptosis. As such, it is a potential therapy for ischemic heart disease.

Role of Statins in Coronavirus-Related Disease (COVID-19): A Retrospective Cohort Study in Northern Italy

Introduction

The outbreak by SARS-CoV-2 has rapidly spread worldwide. The need for specific treatments to adequately stop the inflammatory response and its sequelae is day by day more urgent and many therapeutic strategies were performed since COVID-19 burst in the last months. Statins were thought to be effective against this novel coronavirus for their anti-inflammatory properties, even if the real effects on COVID patients are still partially unexplored.

Methods

We retrospectively evaluated 501 adult patients, consecutively admitted to the two COVID-hospitals of Ferrara’s territory, and divided them into two groups: ST = patients on statin therapy on admission and NST=patients not on statin therapy on admission. We searched for differences between groups in terms of anamnestic, clinical and laboratory data and then in terms of COVID-19 outcomes.

Results

We found significant differences between groups in terms of age, comorbidities, procalcitonin and CPK serum levels: ST patients were older, more comorbid, with lower procalcitonin and higher CPK serum levels. Male sex was, together with the Charlson Comorbidity Index, an independent predictor of needing intensification of care, while age only was a good predictor of in-hospital and 100-day mortality. Differences were also found in the survival functions between the two groups.

Conclusions

After a period of observation of 100 days, ST patients, despite their older age and their greater load of comorbidities, have similar survival functions to NST patients. If adjusted for age and CCI the survival functions of ST group are considerably more favourable than those of the second group.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40292-021-00452-y.

Decreased Mortality Rate Among COVID-19 Patients Prescribed Statins: Data From Electronic Health Records in the US

The severe respiratory illness due to SARS-CoV-2, the virus responsible for coronavirus disease 2019 (COVID-19), is triggered by an intense pro-inflammatory host response. Statins, prescribed primarily for lipid reduction, are known to have anti-inflammatory and immunomodulatory properties and have been associated with a reduced mortality rate among COVID-19 patients taking statins as reported in two recent retrospective studies. However, a meta-analysis that included nine studies showed that statin use did not improve in-hospital outcomes of those with COVID-19. In addition, concerns regarding the use of statins and an increase in COVID-19 infections have been raised, as statins may increase the expression of angiotensin-converting enzyme 2 (ACE2), the primary receptor for the SARS-CoV-2 virus. Our goal was to investigate the effect of statins in COVID-19 patients in a large, diverse patient population across the United States containing nearly 120,000 patients diagnosed with COVID-19. We used propensity score matching of demographics, comorbidities, and medication indication to compare statin-treated patients (N = 2,297) with matched controls (N = 4,594). We observed a small, but statistically significant, decrease in mortality among patients prescribed statins (16.1%) when compared with matched COVID-19-positive controls (18.0 to 20.6%). These results support previous evidence that statins do not increase COVID-19-related mortality and may, in fact, have a mitigating effect on severity of the disease reflected in a slight reduction in mortality. Mixed findings on effects of statins in COVID-19 patients reported in the literature should prompt prospective randomized controlled trials in order to define better who might be advantaged with respect to clinical outcomes.

Cardiovascular Pathophysiology, Epidemiology, and Treatment Considerations of Coronavirus Disease 2019 (COVID-19): A Review

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is rapidly evolving, with important cardiovascular considerations. The presence of underlying cardiovascular risk factors and established cardiovascular disease (CVD) may affect the severity and clinical management of patients with COVID-19. We conducted a review of the literature to summarize the cardiovascular pathophysiology, risk factors, clinical presentations, and treatment considerations of COVID-19 patients with underlying CVD. Angiotensin-converting enzyme 2 (ACE2) has been identified as a functional receptor for the SARS-CoV-2 virus, and it is associated with the cardiovascular system. Hypertension, diabetes, and CVD are the most common comorbidities in COVID-19 patients, and these factors have been associated with the progression and severity of COVID-19. However, elderly populations, who develop more-severe COVID-19 complications, are naturally exposed to these comorbidities, underscoring the possible confounding of age. Observational data support international cardiovascular societies' recommendations to not discontinue ACE inhibitor/angiotensin-receptor blocker therapy in patients with guideline indications for fear of the increased risk of SARS-CoV-2 infection, severe disease, or death. In addition to the cardiotoxicity of experimental antivirals and potential interactions of experimental therapies with cardiovascular drugs, several strategies for cardiovascular protection have been recommended in COVID-19 patients with underlying CVD. Troponin elevation is associated with increased risk of in-hospital mortality and adverse outcomes in patients with COVID-19. Cardiovascular care teams should have a high index of suspicion for fulminant myocarditis-like presentations being SARS-CoV-2 positive, and remain vigilant for cardiovascular complications in COVID-19 patients.

Impact of prior statin use on clinical outcomes in COVID-19 patients: data from tertiary referral hospitals during COVID-19 pandemic in Italy

BACKGROUND

Epidemiological evidence suggests that anti-inflammatory and immunomodulatory properties of statins may reduce the risk of infections and infection-related complications.

OBJECTIVE

We aimed to assess the impact of prior statin use on coronavirus disease (COVID-19) severity and mortality.

METHODS

In this observational multicenter study, consecutive patients hospitalized for COVID-19 were enrolled. In-hospital mortality and severity of COVID-19 assessed with National Early Warning Score (NEWS) were deemed primary and secondary outcomes, respectively. Propensity score (PS) matching was used to obtain balanced cohorts.

RESULTS

Among 842 patients enrolled, 179 (21%) were treated with statins before admission. Statin patients showed more comorbidities and more severe COVID-19 (NEWS 4 [IQR 2-6] vs 3 [IQR 2-5], p < 0.001). Despite having similar rates of intensive care unit admission, noninvasive ventilation, and mechanical ventilation, statin users appeared to show higher mortality rates. After balancing pre-existing relevant clinical conditions that could affect COVID-19 prognosis with PS matching, statin therapy confirmed its association with a more severe disease (NEWS ≥5 61% vs. 48%, p = 0.025) but not with in-hospital mortality (26% vs. 28%, p = 0.185). At univariate logistic regression analysis, statin use was confirmed not to be associated with mortality (OR 0.901; 95% CI: 0.537 to 1.51; p = 0.692) and to be associated with a more severe disease (NEWS≥5 OR 1.7; 95% CI 1.067-2.71; p = 0.026).

CONCLUSIONS

Our results did not confirm the supposed favorable effects of statin therapy on COVID-19 outcomes. Conversely, they suggest that statin use should be considered as a proxy of underlying comorbidities, which indeed expose to increased risks of more severe COVID-19.

Statins and PCSK9 inhibitors: What is their role in coronavirus disease 2019?

Statins and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors interfere with several pathophysiological pathways of coronavirus disease 2019 (COVID-19). Statins may have a direct antiviral effect on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by inhibiting its main protease. Statin-induced up-regulation of angiotensin-converting enzyme 2 (ACE2) may also be beneficial, whereas cholesterol reduction might significantly suppress SARS-CoV-2 by either blocking its host-cell entry through the disruption of lipid rafts or by inhibiting its replication. Available human studies have shown beneficial effects of statins and PCSK9 inhibitors on pneumonia and sepsis. These drugs may act as immunomodulators in COVID-19 and protect against major complications, such as acute respiratory distress syndrome and cytokine release syndrome. Considering their antioxidative, anti-arrhythmic, antithrombotic properties and their beneficial effect on endothelial dysfunction, along with the increased risk of mortality of patients at high cardiovascular risk infected by SARS-CoV-2, statins and PCSK9 inhibitors might prove effective against the cardiovascular and thromboembolic complications of COVID-19. On the whole, randomized clinical trials are needed to establish routine use of statins and PCSK9 inhibitors in the treatment of SARS-CoV-2 infection. In the meantime, it is recommended that lipid-lowering therapy should not be discontinued in COVID-19 patients unless otherwise indicated.

Relation of Statin Use Prior to Admission to Severity and Recovery Among COVID-19 Inpatients

The impact of statins, angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers (ARBs) on coronavirus disease 2019 (COVID-19) severity and recovery is important given their high prevalence of use among individuals at risk for severe COVID-19. We studied the association between use of statin/angiotensin-converting enzyme inhibitors/ARB in the month before hospital admission, with risk of severe outcome, and with time to severe outcome or disease recovery, among patients hospitalized for COVID-19. We performed a retrospective single-center study of all patients hospitalized at University of California San Diego Health between February 10, 2020 and June 17, 2020 (n = 170 hospitalized for COVID-19, n = 5,281 COVID-negative controls). Logistic regression and competing risks analyses were used to investigate progression to severe disease (death or intensive care unit admission), and time to discharge without severe disease. Severe disease occurred in 53% of COVID-positive inpatients. Median time from hospitalization to severe disease was 2 days; median time to recovery was 7 days. Statin use prior to admission was associated with reduced risk of severe COVID-19 (adjusted OR 0.29, 95%CI 0.11 to 0.71, p < 0.01) and faster time to recovery among those without severe disease (adjusted HR for recovery 2.69, 95%CI 1.36 to 5.33, p < 0.01). The association between statin use and severe disease was smaller in the COVID-negative cohort (p for interaction = 0.07). There was potential evidence of faster time to recovery with ARB use (adjusted HR 1.92, 95%CI 0.81 to 4.56). In conclusion, statin use during the 30 days prior to admission for COVID-19 was associated with a lower risk of developing severe COVID-19, and a faster time to recovery among patients without severe disease.

Epigenetic susceptibility to severe respiratory viral infections and its therapeutic implications: a narrative review

The emergence of highly pathogenic strains of influenza virus and coronavirus (CoV) has been responsible for large epidemic and pandemic outbreaks characterised by severe pulmonary illness associated with high morbidity and mortality. One major challenge for critical care is to stratify and minimise the risk of multi-organ failure during the stay in the intensive care unit (ICU). Epigenetic-sensitive mechanisms, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) methylation, histone modifications, and non-coding RNAs may lead to perturbations of the host immune-related transcriptional programmes by regulating chromatin structure and gene expression patterns. Viruses causing severe pulmonary illness can use epigenetic-regulated mechanisms during host-pathogen interaction to interfere with innate and adaptive immunity, adequacy of inflammatory response, and overall outcome of viral infections. For example, Middle East respiratory syndrome-CoV and H5N1 can affect host antigen presentation through DNA methylation and histone modifications. The same mechanisms would presumably occur in patients with coronavirus disease 2019, in which tocilizumab may epigenetically reduce microvascular damage. Targeting epigenetic pathways by immune modulators (e.g. tocilizumab) or repurposed drugs (e.g. statins) may provide novel therapeutic opportunities to control viral-host interaction during critical illness. In this review, we provide an update on epigenetic-sensitive mechanisms and repurposed drugs interfering with epigenetic pathways which may be clinically suitable for risk stratification and beneficial for treatment of patients affected by severe viral respiratory infections.

Key Player in Cardiac Hypertrophy, Emphasizing the Role of Toll-Like Receptor 4

Toll-like receptor 4 (TLR4), a key pattern recognition receptor, initiates the innate immune response and leads to chronic and acute inflammation. In the past decades, accumulating evidence has implicated TLR4-mediated inflammatory response in regulation of myocardium hypertrophic remodeling, indicating that regulation of the TLR4 signaling pathway may be an effective strategy for managing cardiac hypertrophy's pathophysiology. Given TLR4's significance, it is imperative to review the molecular mechanisms and roles underlying TLR4 signaling in cardiac hypertrophy. Here, we comprehensively review the current knowledge of TLR4-mediated inflammatory response and its interaction ligands and co-receptors, as well as activation of various intracellular signaling. We also describe the associated roles in promoting immune cell infiltration and inflammatory mediator secretion, that ultimately cause cardiac hypertrophy. Finally, we provide examples of some of the most promising drugs and new technologies that have the potential to attenuate TLR4-mediated inflammatory response and prevent or reverse the ominous cardiac hypertrophy outcomes.

Statins and SARS-CoV-2 disease: Current concepts and possible benefits

BACKGROUND AND AIMS

Inflammation-mediated tissue injury is the major mechanism involved in the pathogenesis of coronavirus disease 2019 (COVID-2019), caused by Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). Statins have well-established anti-inflammatory, anti-thrombotic and immuno-modulatory effects. They may also influence viral entry into human cells.

METHODS

A literature search was done using PubMed and Google search engines to prepare a narrative review on this topic.

RESULTS

Statins interact with several different signaling pathways to exert their anti-inflammatory and vasculoprotective effects. They also variably affect cholesterol content of cell membranes and interfere with certain coronavirus enzymes involved in receptor-binding. Both these actions may influence SARS-CoV-2 entry into human cells. Statins also upregulate expression of angiotensin-converting enzyme 2 receptors on cell surfaces which may promote viral entry into the cells but at the same time, may minimize tissue injury through production of angiotensin [1-7]. The net impact of these different effects on COVID-19 pathogenesis is not clear. However, the retrospective clinical studies have shown that statin use is potentially associated with lower risk of developing severe illness and mortality and a faster time to recovery in patients with COVID-19.

CONCLUSIONS

Early observations suggest beneficial effect of statin use on the clinical outcomes in COVID-19. Prospective randomized studies as well as well-designed laboratory studies are required to confirm these observations and to elucidate the mechanisms of such benefits, if proven.

Pharmaco-Immunomodulatory Therapy in COVID-19

The severe acute respiratory syndrome coronavirus 2 associated coronavirus disease 2019 (COVID-19) illness is a syndrome of viral replication in concert with a host inflammatory response. The cytokine storm and viral evasion of cellular immune responses may play an equally important role in the pathogenesis, clinical manifestation, and outcomes of COVID-19. Systemic proinflammatory cytokines and biomarkers are elevated as the disease progresses towards its advanced stages, and correlate with worse chances of survival. Immune modulators have the potential to inhibit cytokines and treat the cytokine storm. A literature search using PubMed, Google Scholar, and ClinicalTrials.gov was conducted through 8 July 2020 using the search terms ‘coronavirus’, ‘immunology’, ‘cytokine storm’, ‘immunomodulators’, ‘pharmacology’, ‘severe acute respiratory syndrome 2’, ‘SARS-CoV-2’, and ‘COVID-19’. Specific immune modulators include anti-cytokines such as interleukin (IL)-1 and IL-6 receptor antagonists (e.g. anakinra, tocilizumab, sarilumab, siltuximab), Janus kinase (JAK) inhibitors (e.g. baricitinib, ruxolitinib), anti-tumor necrosis factor-α (e.g. adalimumab, infliximab), granulocyte–macrophage colony-stimulating factors (e.g. gimsilumab, lenzilumab, namilumab), and convalescent plasma, with promising to negative trials and other data. Non-specific immune modulators include human immunoglobulin, corticosteroids such as dexamethasone, interferons, statins, angiotensin pathway modulators, macrolides (e.g. azithromycin, clarithromycin), hydroxychloroquine and chloroquine, colchicine, and prostaglandin D2 modulators such as ramatroban. Dexamethasone 6 mg once daily (either by mouth or by intravenous injection) for 10 days may result in a reduction in mortality in COVID-19 patients by one-third for patients on ventilators, and by one-fifth for those receiving oxygen. Research efforts should focus not only on the most relevant immunomodulatory strategies but also on the optimal timing of such interventions to maximize therapeutic outcomes. In this review, we discuss the potential role and safety of these agents in the management of severe COVID-19, and their impact on survival and clinical symptoms.

Pros and cons for use of statins in people with coronavirus disease-19 (COVID-19)

BACKGROUND AND AIMS

Morbidity and mortality from coronavirus disease 2019 (COVID-19) is higher among people with diabetes mellitus (DM), hypertension, and cardiovascular disease (CVD). Statins are used in the majority of people with DM and CVD. This mini-review discusses the current understanding of benefit-risk ratio of use of statins in COVID-19.

METHODS

We searched PubMed database using specific keywords related to our aims till June 12, 2020. Full text of relevant articles published in English language were retrieved and reviewed.

RESULTS

Statins, with their immunomodulatory, anti-inflammatory, anti-thrombotic, and anti-oxidant properties, have the potential to reduce severity of lung injury in, and mortality from, severe acute respiratory syndrome-coronavirus 2 (SARS-CoV2) infections. Statin-induced upregulation of angiotensin-converting enzyme-2 (ACE2) has the potential to reduce lung injury from excess angiotensin II. By disrupting lipid rafts, statins have the potential to reduce viral entry into cells. However, benefit-risk ratio of its complex interaction with MYD88 gene expression on outcomes in COVID-19, and the putative role of low serum LDL cholesterol in increasing severity of SARS-CoV2 infection need further clarification.

CONCLUSIONS

People with COVID-19, who are already on statins for an underlying co-morbid condition, should continue on it unless there are specific contraindications. De-novo use of statins in people with COVID-19 with no underlying co-morbidity might be beneficial but awaits substantiation in clinical trials; till that time, de novo use of statins in COVID 19 should be limited to a clinical trial setting.

In-Hospital Use of Statins Is Associated with a Reduced Risk of Mortality among Individuals with COVID-19

Statins are lipid-lowering therapeutics with favorable anti-inflammatory profiles and have been proposed as an adjunct therapy for COVID-19. However, statins may increase the risk of SARS-CoV-2 viral entry by inducing ACE2 expression. Here, we performed a retrospective study on 13,981 patients with COVID-19 in Hubei Province, China, among which 1,219 received statins. Based on a mixed-effect Cox model after propensity score-matching, we found that the risk for 28-day all-cause mortality was 5.2% and 9.4% in the matched statin and non-statin groups, respectively, with an adjusted hazard ratio of 0.58. The statin use-associated lower risk of mortality was also observed in the Cox time-varying model and marginal structural model analysis. These results give support for the completion of ongoing prospective studies and randomized controlled trials involving statin treatment for COVID-19, which are needed to further validate the utility of this class of drugs to combat the mortality of this pandemic.

Teaching Old Drugs New Tricks: Statins for COVID-19?

The COVID-19 pandemic has driven unprecedented efforts to identify existing treatments that can be quickly and effectively repurposed to reduce morbidity and mortality. In this issue of Cell Metabolism, Zhang et al. (2020) report an association between statin use and improved outcomes in a large observational study of hospitalized COVID-19 patients. Given the widespread availability, low cost, and safety of statins, this promising result should be further investigated in randomized controlled trials.

Pharmacotherapeutic considerations for the management of cardiovascular diseases among hospitalized COVID-19 patients

INTRODUCTION

Cardiovascular diseases (CVDs) are among the most frequently identified comorbidities in hospitalized patients with COVID-19. Patients with CV comorbidities are typically prescribed with long-term medications. We reviewed the management of co-medications prescribed for CVDs among hospitalized COVID-19 patients.

AREAS COVERED

There is no specific contraindication or caution related to COVID-19 on the use of antihypertensives unless patients develop severe hypotension from septic shock where all antihypertensives should be discontinued or severe hyperkalemia in which continuation of renin-angiotensin system inhibitors is not desired. The continuation of antiplatelet or statin is not desired when severe thrombocytopenia or severe transminitis develop, respectively. Patients with atrial fibrillation receiving oral anticoagulants, particularly those who are critically ill, should be considered for substitution to parenteral anticoagulants.

EXPERT OPINION

An individualized approach to medication management among hospitalized COVID-19 patients with concurrent CVDs would seem prudent with attention paid to changes in clinical conditions and medications intended for COVID-19. The decision to modify prescribed long-term CV medications should be entailed by close follow-up to check if a revision on the decision is needed, with resumption of any long-term CV medication before discharge if it is discontinued during hospitalization for COVID-19, to ensure continuity of care.

Potential repurposed SARS-CoV-2 (COVID-19) infection drugs

The global outbreak of COVID-19 viral infection is associated with the absence of specific drug(s) for fighting this viral infection. About 10 million people are already infected, about 500 000 deaths all over the world to date. Great efforts have been made to find solutions for this viral infection, either vaccines, monoclonal antibodies, or small molecule drugs; this can stop the spread of infection to avoid the expected human, economic and social catastrophe associated with this infection. In the literature and during clinical trials in hospitals, several FDA approved drugs for different diseases have the potential to treat or reduce the severity of COVID-19. Repurposing of these drugs as potential agents to treat COVID-19 reduces the time and cost to find effective COVID-19 agents. This review article summarizes the present situation of transmission, pathogenesis and statistics of COVID-19 in the world. Moreover, it includes chemistry, mechanism of action at the molecular level of the possible drug molecules which are liable for redirection as potential COVID-19 therapeutic agents. This includes polymerase inhibitors, protease inhibitors, malaria drugs, lipid lowering statins, rheumatoid arthritis drugs and some miscellaneous agents. We offer research data and knowledge about the chemistry and biology of potential COVID-19 drugs for the research community in this field.

TLR4 mediates inflammation and hepatic fibrosis induced by chronic intermittent hypoxia in rats

Obstructive sleep apnea syndrome (OSAS) is a common and complex disorder that is associated with liver injury. Moreover, previous studies have revealed that chronic intermittent hypoxia (CIH) is associated with the development of non-alcoholic fatty liver disease and hepatic fibrosis. However, the underlying molecular mechanisms remain largely unknown. The present study aimed to investigate whether chronic intermittent hypoxia induced hepatic fibrosis, in addition to determining its underlying mechanisms, in CIH model rats using immunohistochemistry, western blotting and reverse transcription-quantitative PCR. The present results suggested that CIH caused hepatic fibrosis and increased the expression levels of interleukin (IL)-1β, IL-8, monocyte chemotactic-1, tumor necrosis factor-α, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in the liver; these conditions could be reversed by Toll-like receptor 4 (TLR4) short hairpin RNA lentivirus treatment. Moreover, immunohistochemistry and western blotting results indicated that TLR4 and NF-κB expression levels were significantly increased in the CIH and CIH-TLR4 empty vector lentivirus group. However, protein expression levels of TLR4, NF-κB, inhibitor of NF-κB and phosphorylated-mitogen-activated protein kinase (MAPK)-1 in the hypoxia/reoxygenation group were significantly higher compared with the control group (P<0.05), and these results were reversed by the MAPK inhibitor U0126 in vitro. Collectively, the present preliminary results suggested that inflammation and the TLR4/NF-κB/MAPK signaling pathway may be involved in CIH-induced liver fibrosis.

Anti-inflammatory Action of Statins in Cardiovascular Disease: the Role of Inflammasome and Toll-Like Receptor Pathways

Atherosclerosis is one type of cardiovascular disease (CVD) in which activation of the NLRP3 inflammasome and toll-like receptor (TLR) pathways is implicated. One of the most effective treatments for atherosclerosis is the use of statin medications. Recent studies have indicated that statins, in addition to their lipid-lowering effects, exert inhibitory and/or stimulatory effects on the NLRP3 inflammasome and TLRs. Some of the statins lead to activation of the inflammasome and subsequently cause secretion of IL-1β and IL-18. Thus, these actions may further aggravate the disease. On the other hand, some statins cause inhibition of the inflammasome or TLRs and along with lipid-lowering, help to improve the disease by reducing inflammation. In this article, we discuss these contradictory studies and the mechanisms of action of statins on the NLRP3 inflammasome and TLR pathways. The dose-dependent effects of statins on the NLRP3 complex are related to their chemistry, pharmacokinetic properties, and danger signals. Lipophilic statins have more pleiotropic effects on the NLRP3 complex in comparison to hydrophilic statins. Statins can suppress TLR4/MyD88/NF-ĸB signaling and cause an immune response shift to an anti-inflammatory response. Furthermore, statins inhibit the NF-ĸB pathway by decreasing the expression of TLRs 2 and 4. Statins are cost-effective drugs, which should have a continued future in the treatment of atherosclerosis due to both their immune-modulating and lipid-lowering effects.

Role of the Nrdp1 in Brain Injury Induced by Chronic Intermittent Hypoxia in Rats via Regulating the Protein Levels of ErbB3

Obstructive sleep apnea syndrome (OSAS) is known as a repeated obstruction of the upper airway during sleep, leading to generalized hypoxia episodes and associated with cardiovascular and cerebrovascular diseases. We mainly explored the role of neuregulin receptor degradation protein-1 (Nrdp1, also known as FLRF) in brain injury induced by chronic intermittent hypoxia (CIH) in rats. Wistar rats were randomly divided into 4 groups (n = 12 per group), including the sham + adeno-associated virus-NC (AAV-NC) group, the sham + AAV-siNrdp1 group, the IH-4w (intermittent hypoxia for 4 weeks) + AAV-NC group, and the IH-4w + AAV-siNrdp1 group. Morphologic changes in brain tissue were observed by hematoxylin and eosin (HE) staining. Apoptosis in the hippocampus was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining. Spatial learning and memory were assessed by the Morris water maze test. The expression of Nrdp1 mRNA and protein in the hippocampus was detected by qualitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. The concentration of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in serum was detected via enzyme-linked immunosorbent assay (ELISA) kits. Nrdp1 expression was increased after intermittent hypoxia exposure over time. Western blotting and H&E results showed that pathological changes of hippocampus neurons in chronic intermittent hypoxia rat were diminished by shNrdp1. Western blotting and TUNEL staining showed that apoptotic cells in the hippocampus of CIH rats were decreased by shNrdp1. The Morris water maze results proved that shNrdp1 improved spatial learning performance of chronic intermittent hypoxia rats. ELISA kits results showed that CIH-induced inflammatory response was decreased by shNrdp1. Western blotting and qRT-PCR results showed protein expression of ErbB3 in the hippocampus of CIH rats. Nrdp1 could regulate ErbB3 protein levels in brain-injured rats with CIH, which demonstrates that Nrdp1 is a potential therapeutic target in the cognition deficits associated with OSAS.

TLR2 antagonism attenuates the hippocampal neuronal damage in a murine model of sleep apnea via inhibiting neuroinflammation and oxidative stress

BACKGROUND

Obstructive sleep apnea (OSA) in humans chronically promotes the neuronal damage in the hippocampus. Toll-like receptor 2 (TLR2) is pivotal for the development of numerous hippocampal diseases. Chronic intermittent hypoxia (CIH) is a prominent feature of OSA. Here in our study, the effects of TLR2 antagonism on the neural damage elicited by CIH were examined.

METHODS

Ortho-vanillin (O-vanillin) is an inhibitor of TLR2. Adult male mice were subjected to 8 h of intermittent hypoxia per day with or without O-vanillin for 28 days. Neuronal damage, the number of microglia, the interaction of TLR2 with its adapter protein myeloid differentiation factor 88 (MYD88), the expressions of inflammatory cytokines, and the oxidative stress were observed.

RESULTS

O-vanillin inhibited the increased interaction of TLR2 and MyD88, the activation of NFκB, the aggregation of microglia, the overexpression of proinflammatory agents, the elevation of oxidative stress, and hippocampal neuron cell apoptosis induced by CIH.

CONCLUSIONS

Our experiments indicate that TLR2 antagonism may alleviate the hippocampal neuronal damage caused by CIH via inhibiting neuroinflammation and oxidative stress.

Clinical and experimental aspects of breathing modulation by inflammation

Neuroinflammation is produced by local or systemic alterations and mediated mainly by glia, affecting the activity of various neural circuits including those involved in breathing rhythm generation and control. Several pathological conditions, such as sudden infant death syndrome, obstructive sleep apnea and asthma exert an inflammatory influence on breathing-related circuits. Consequently breathing (both resting and ventilatory responses to physiological challenges), is affected; e.g., responses to hypoxia and hypercapnia are compromised. Moreover, inflammation can induce long-lasting changes in breathing and affect adaptive plasticity; e.g., hypoxic acclimatization or long-term facilitation. Mediators of the influences of inflammation on breathing are most likely proinflammatory molecules such as cytokines and prostaglandins. The focus of this review is to summarize the available information concerning the modulation of the breathing function by inflammation and the cellular and molecular aspects of this process. I will consider: 1) some clinical and experimental conditions in which inflammation influences breathing; 2) the variety of experimental approaches used to understand this inflammatory modulation; 3) the likely cellular and molecular mechanisms.

Effect of statins on toll-like receptors: a new insight to pleiotropic effects

The toll-like receptors (TLRs) are a class of transmembrane-spanning receptors that are sentinels of both innate and adaptive immunity. Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) are the most commonly prescribed therapeutic agents for treating hypercholesterolemia globally. However, statin therapy appears to have pleiotropic effects including attenuation of chronic low-grade inflammation and modulation of TLR activity. Statins through abolition of TLR4 expression and regulation of the TLR4/Myd88/NF-κB signaling pathway may slow the progression of atherosclerosis and other inflammatory diseases. In this review, we have focused on the impact and mechanism of action of statins on cardiovascular and non-cardiovascular diseases.

Toll-like receptor-4 deficiency alleviates chronic intermittent hypoxia-induced renal injury, inflammation, and fibrosis

BACKGROUND

Obstructive sleep apnea (OSA)-associated chronic kidney disease is mainly caused by chronic intermittent hypoxia (CIH) triggered renal damage. This study aims to investigate the role of toll-like receptor-4 (TLR4) in underlying mechanism involved chronic intermittent hypoxia (CIH)-induced renal damage.

METHODS

C57BL/6J mice with normal TLR4 (TLR4 WT) or deficient TLR4 (TLR4 KO) were divided into four groups and exposed to normal air (NA) and CIH: TLR4 WT + NA, TLR4 KO + NA, TLR4 WT + CIH, and TLR4 KO + CIH. CIH lasted for 8 h/day and 7 days/week for 6 weeks. Renal injury and inflammation were evaluated by histology and ELISA. Renal tubular apoptosis, macrophages, and fibroblasts recruitment were determined by TUNEL assay, immunofluorescence, and western blot.

RESULTS

In response to CIH, TLR4 deficiency alleviated renal histological injury, renal dysfunction, and fibrosis. TLR4 deficiency ameliorated renal dysfunction (serum BUN and creatinine) and tubular endothelial apoptosis determined by immunofluorescence staining of CD31 and TUNEL, and western blot of apoptotic protein (caspase-3, c-caspase-3, and Bax/Bcl-2 ratio). Furthermore, we also found TLR4 deficiency abrogated CIH-induced macrophages (CD68) and fibroblasts (α-SMA) recruitment, further reducing expression of extra-cellular matrix protein (collagen I and collagen IV) and inflammatory cytokines release (IL-6, TNF-α, and MCP-1). Finally, we used immunohistochemistry to demonstrate that TLR4 deficiency attenuated increased expression of MyD88 and NF-kB p65 after CIH treatment.

CONCLUSIONS

Our data suggest that TLR4 plays a vital role in CIH-induced renal injury, inflammation and fibrosis, and inhibition of TLR4 probably provides a therapeutic potential for CIH-induced kidney damage.