The Angiotensin II Receptor Neprilysin Inhibitor LCZ696 Inhibits the NLRP3 Inflammasome By Reducing Mitochondrial Dysfunction in Macrophages and Alleviates Dextran Sulfate Sodium-induced Colitis in a Mouse Model.

The intracellular sensor protein complex known as the NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome plays a crucial role in regulating inflammatory diseases by overseeing the production of interleukin (IL)-1ß and IL-18. Targeting its abnormal activation with drugs holds significant promise for inflammation treatment. This study highlights LCZ696, an angiotensin receptor-neprilysin inhibitor, as an effective suppressor of NLRP3 inflammasome activation in macrophages stimulated by ATP, nigericin, and monosodium urate. LCZ696 also reduces caspase-11 and GSDMD activation, lactate dehydrogenase release, propidium iodide uptake, and the extracellular release of NLRP3 and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) in ATP-activated macrophages, suggesting a potential mitigation of pyroptosis. Mechanistically, LCZ696 lowers mitochondrial reactive oxygen species and preserves mitochondrial integrity. Importantly, it does not significantly impact NLRP3, proIL-1ß, inducible nitric oxide synthase, cyclooxygenase-2 expression, or NF-κB activation in lipopolysaccharide-activated macrophages. LCZ696 partially inhibits the NLRP3 inflammasome through the induction of autophagy. In an in vivo context, LCZ696 alleviates NLRP3-associated colitis in a mouse model by reducing colonic expression of IL-1ß and tumor necrosis factor-α. Collectively, these findings suggest that LCZ696 holds significant promise as a therapeutic agent for ameliorating NLRP3 inflammasome activation in various inflammatory diseases, extending beyond its established use in hypertension and heart failure treatment.

The leaves of the seasoning plant Litsea cubeba inhibit the NLRP3 inflammasome and ameliorate dextran sulfate sodium-induced colitis in mice.

The intracellular sensor NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome controls caspase-1 activity and the maturation and release of the cytokines interleukin (IL)-1ß and IL-18. The NLRP3 inflammasome has attracted the attention of the pharmaceutical industry because it promotes the pathogenesis of many diseases, making it a promising target for drug development. Litsea cubeba (Lour.) is a plant traditionally used as a seasoning in Taiwan and in other Asian countries. In this study, we investigated the inhibitory activity of the leaves of L. cubeba against the NLRP3 inflammasome. We found that the ethanol extract of L. cubeba leaves (MLE) inhibited the NLRP3 inflammasome in macrophages by reducing caspase-1 activation and IL-1ß secretion. MLE reduced pyroptosis in macrophages and inhibited the release of NLRP3 and apoptosis-associated speck-like protein containing a CARD (ASC). In a mechanistic study, MLE reduced mitochondrial reactive oxygen species (ROS) production and preserved mitochondrial integrity, which led to reduced mitochondrial DNA release into the cytosol. MLE did not reduce the expression levels of NLRP3, IL-1ß precursor or TNF-α in lipopolysaccharide (LPS)-activated macrophages. These results indicated that MLE inhibited the NLRP3 inflammasome by suppressing the activation signals of the NLRP3 inflammasome but not by reducing the priming signal induced by LPS. In addition, oral administration of MLE (20-80 mg/kg) ameliorated dextran sulfate sodium (DSS)-induced colitis in a mouse model. Notably, mice that received MLE (1 and 2 g/kg) daily for 7 days did not exhibit visible side effects. Gas chromatography-mass spectrometry (GC-MS) analysis found that α-Terpinyl acetate (27.2%) and 1,8-Cineole (17.7%) were the major compounds in MLE. These results indicated that L. cubeba leaves have the potential to be a nutraceutical for preventing and improving NLRP3 inflammasome-related diseases.

Repositioning of the Angiotensin II Receptor Antagonist Candesartan as an Anti-Inflammatory Agent With NLRP3 Inflammasome Inhibitory Activity.

Aberrant activation of the NLRP3 inflammasome promotes the pathogenesis of many inflammatory diseases. The development of the NLRP3 inflammasome inhibitors from existing drugs for new therapeutic purposes is becoming more important. Candesartan is an angiotensin II receptor antagonist widely used as a blood pressure-lowering drug; however, the inhibitory potential of candesartan on the NLRP3 inflammasome has not yet been investigated. We demonstrated that candesartan significantly inhibited the NLRP3 inflammasome and pyroptosis in macrophages. Mechanistic analysis revealed that candesartan inhibited the expression of NLRP3 and proIL-1ß by suppressing NF-κB activation and reducing the phosphorylation of ERK1/2 and JNK1/2. Candesartan reduced mitochondrial damage and inhibited the NLRP3 inflammasome assembly by suppressing NLRP3 binding to PKR, NEK7 and ASC. In addition, candesartan inhibited IL-1ß secretion partially through autophagy induction. Furthermore, oral administration of candesartan reduced peritoneal neutrophil influx, NLRP3 and ASC expression in peritoneal cells, and lavage fluid concentrations of active caspase-1, IL-1ß, IL-6 and MCP-1 in uric acid crystal-injected mice. These results indicated that candesartan has board anti-inflammatory effects and has the potential to be repositioned to ameliorate inflammatory diseases or NLRP3-associated complications.

Changes of antithrombotic prescription in atrial fibrillation patients with acute coronary syndrome or percutaneous coronary intervention and the subsequent impact on long-term outcomes: a longitudinal cohort study.

OBJECTIVES: The choice of optimal antithrombotic therapy in atrial fibrillation (AF) patients with acute coronary syndrome (ACS) or percutaneous coronary intervention (PCI) remains controversial. The aim of this longitudinal cohort study is to investigate the prescribing pattern of antithrombotic regimen in different cohorts and its subsequent impact. SETTING AND DESIGN: Longitudinal data from the Tri-Service General Hospital-Coronary Heart Disease (TSGH-CHD) registry, between January 2016 and August 2018 was screened. PARTICIPANTS AND METHOD: Patients with prior history of nonvalvular AF, who had ACS presentation or underwent PCI were selected, and these patients were divided into cohort 1 and cohort 2, according to the index date of antithrombotic prescription before and after the PIONEER AF-PCI study. PRIMARY AND SECONDARY OUTCOMES: The primary safety endpoints were composites of major bleeding and/or clinically relevant non-major bleeding. The secondary efficacy endpoints included the occurrence of all-cause mortality, stroke/systemic embolization, nonfatal myocardial infarction (MI), and >30-days coronary revascularization. RESULTS: A total of 121 patients were included into analysis (cohort 1=35; cohort 2=86). Comparing with cohort 1, the prescription rate of triple antithrombotic therapy (TAT) increased from 17.1 to 38.4%, especially the regimen with dual antiplatelet therapy (DAPT) plus low-dose non-vitamin-K dependent oral anticoagulation (NOAC). However, the prescription rate of dual antithrombotic therapy (DAT) decreased (14.3-10.5%), as well as the prescription rate of DAPT (68.6-51.2%). These changes of antithrombotic prescription across different cohorts were not associated with risk of adverse safety (HR= 0.87; 95% CI, 0.42-1.80, p=0.710) and efficacy outcomes (HR=0.96; 95% CI, 0.40-2.32, p=0.930). CONCLUSIONS: Entering the NOAC era, the prescription of TAT increased alongside the decrease in DAT. As the prescription rate of DAPT without anticoagulation remained high, future efforts are mandatory to improve the implementation of guidelines and clinical practice.

Profiles of Hospitalized Patients with Angiographic Coronary Heart Disease in Taiwan during 2014-2016: Report of a Tertiary Hospital.

BACKGROUND: The Taiwan Society of Cardiology (TSOC) has established multicenter registries for coronary artery disease (CAD) to investigate clinical characteristics, management and risks for mortality. However, the impacts of newly-emerged evidence-based therapies, including the use of drug-eluting stents (DESs), on patients with CAD in Taiwan remain unclear. METHODS: The Tri-Service General Hospital-Coronary Heart Disease (TSGH-CHD) registry is a single-center, prospective, longitudinal registry in Taiwan containing data from 2014-2016. Individuals who were admitted for coronary angiography were enrolled. Patient profiles, management and in-hospital outcome data were collected. RESULTS: We included 3352 patients: 2349 with stable angina and 1003 with acute coronary syndrome (ACS). In the stable angina group, both patients receiving stenting and those receiving medical treatment had a 0.7% mortality rate; DESs were used in 70.4% of the patients receiving stenting. In the ACS group, the patients receiving stenting and those receiving medical treatment had a 4.9% and 10.7% mortality rate, respectively; DESs were used in 63.1% of the patients receiving stenting. In the 2008-2010 Taiwan ACS registry, DESs were used in only 28% of all stenting procedures, and the estimated hospital mortality rate was 1.8%. Multivariate analysis indicated that older age, prior stroke, and cardiogenic shock on admission were associated with an increased risk of in-hospital mortality in the ACS group. CONCLUSIONS: Compared with the Taiwan ACS cohort, the TSGH-CHD registry revealed increased DES use and increased disease complexity and severity after 2010. Although unlikely to significantly improve survival, interventionists seemed to perform high-risk procedures for complex CAD more often in the new DES era.

Prognostic Effect of Restoring Sinus Rhythm in Patients with New-Onset Atrial Fibrillation during Acute Coronary Syndrome.

BACKGROUND: New-onset atrial fibrillation (NOAF) in acute coronary syndrome (ACS) may be associated with a poor prognosis. However, whether restoring sinus rhythm (SR) at discharge in patients with ACS improves outcomes remains unknown. METHODS: A total of 552 patients with ACS at an emergency department during 2011-2016 were enrolled. According to documented electrocardiography at admission and medical records, the patients were classified into without atrial fibrillation (WAF), NOAF, and prior atrial fibrillation (PAF) groups. Major adverse events (MAEs) were defined as cardiac death, recurrent myocardial infarction, heart failure requiring hospitalization, target lesion revascularization, and stroke. The mean follow-up period of MAEs was 25 ± 15 months. RESULTS: Compared with the NOAF and PAF groups, the WAF group was younger and had a significantly lower heart rate, prior stroke rate, CHA2DS2-VASc score, and lower Global Registry of Acute Coronary Events (GRACE) score in the emergency department (p < 0.001). The patients in the NOAF group had the highest incidence of MAEs (p < 0.001) during follow-up, and those whose SR was restored at discharge had a lower MAE rate than those with AF at discharge (p = 0.001). In multivariable analysis, prior myocardial infarction, GRACE score, use of beta-blockers, and restoring SR at discharge were independent predictors of MAEs in the NOAF group. CONCLUSIONS: The patients with ACS who presented with NOAF had worse outcomes than those with PAF or WAF. The patients with NOAF whose rhythm was restored to SR at discharge were associated with better outcomes than those with AF at discharge.

Corrigendum: A Synthetic Small Molecule F240B Decreases NLRP3 Inflammasome Activation by Autophagy Induction.

[This corrects the article DOI: 10.3389/fimmu.2020.607564.].

A Synthetic Small Molecule F240B Decreases NLRP3 Inflammasome Activation by Autophagy Induction.

Conjugated polyenes are a class of widely occurring natural products with various biological functions. We previously identified 4-hydroxy auxarconjugatin B (4-HAB) as anti-inflammatory agent with an IC50 of ~20 µM. In this study, we synthesized a new anti-inflammatory 4-HAB analogue, F240B, which has an IC50 of less than 1 µM. F240B dose-dependently induced autophagy by increasing autophagic flux, LC3 speck formation and acidic vesicular organelle formation. F240B inhibited NACHT, LRR and PYD domain-containing protein 3 (NLRP3) inflammasome activation through autophagy induction. In a mechanistic study, F240B inhibited interleukin (IL)-1ß (IL-1ß) precursor expression, promoted degradation of NLRP3 and IL-1ß, and reduced mitochondrial membrane integrity loss in an autophagy-dependent manner. Additionally, F240B inhibited apoptosis-associated speck-like protein containing a CARD (ASC) oligomerization and speck formation without affecting the interaction between NLRP3 and ASC or NIMA-related kinase 7 (NEK7) and double-stranded RNA-dependent kinase (PKR). Furthermore, F240B exerted in vivo anti-inflammatory activity by reducing the intraperitoneal influx of neutrophils and the levels of IL-1ß, active caspase-1, IL-6 and monocyte chemoattractant protein-1 (MCP-1) in lavage fluids in a mouse model of uric acid crystal-induced peritonitis. In conclusion, F240B attenuated the NLRP3 inflammasome through autophagy induction and can be developed as an anti-inflammatory agent in the future.

Association of preexisting hypertension with the morality in patients with systolic heart failure in Taiwan: The TSOC-HFrEF registry.

PURPOSE: To investigate the association of preexisting hypertension at admission with the mortality in patients with systolic heart failure (HF). METHOD: We prospectively investigated the association of preexisting hypertension with the mortality among 1351 patients with HF in Taiwan during an average 12 months (range: 8 months-18 months) follow-up period. A multivariate cox regression analysis for the overall cohort and a subgroup analysis by age were performed. RESULTS: After adjustment for all potential risk factors, the associations of preexisting hypertension with cardiovascular mortality were significantly reduced in the overall cohort and those aged less than 65 years (hazard ratios (HR): 0.53, 95% confidence intervals (CI): 0.33-0.84, and 0.28, 95% CI: 0.11-0.67, respectively). However, the associations with all-cause mortality were not significantly different in these two groups (HR: 0.77, 95% CI: 0.54-1.09, and 0.59, 95% CI: 0.32-1.07, respectively). Furthermore, the associations were all nonsignificant in the patients aged older than 65 years. CONCLUSION: Preexisting hypertension have an inverse association with cardiovascular mortality in the Asian patients with systolic HF, particularly for those with younger ages.

Repositioning of the ß-Blocker Carvedilol as a Novel Autophagy Inducer That Inhibits the NLRP3 Inflammasome.

The NLRP3 inflammasome is a multiprotein complex that plays a key role in the innate immune system, and aberrant activation of this complex is involved in the pathogenesis of inflammatory diseases. Carvedilol (CVL) is an α-, ß-blocker used to treat high blood pressure and congestive heart failure; however, some benefits beyond decreased blood pressure were observed clinically, suggesting the potential anti-inflammatory activity of CVL. In this report, the inhibitory potential of CVL toward the NLRP3 inflammasome and the possible underlying molecular mechanisms were studied. Our results showed that CVL attenuated NLRP3 inflammasome activation and pyroptosis in mouse macrophages, without affecting activation of the AIM2, NLRC4 and non-canonical inflammasomes. Mechanistic analysis revealed that CVL prevented lysosomal and mitochondrial damage and reduced ASC oligomerization. Additionally, CVL caused autophagic induction through a Sirt1-dependent pathway, which inhibited the NLRP3 inflammasome. In the in vivo mouse model of NLRP3-associated peritonitis, oral administration of CVL reduced (1) peritoneal recruitment of neutrophils; (2) the levels of IL-1ß, IL-18, active caspase-1, ASC, IL-6, TNF-α, MCP-1, and CXCL1 in the lavage fluids; and (3) the levels of NLRP3 and HO-1 in the peritoneal cells. Our results indicated that CVL is a novel autophagy inducer that inhibits the NLRP3 inflammasome and can be repositioned for ameliorating NLRP3-associated complications.

Clinical Characteristics of Patients Less than Forty Years Old with Coronary Artery Disease in Taiwan: A Cross-Sectional Study.

BACKGROUND: Coronary artery disease (CAD) rarely occurs in young adults. Our objective was to investigate the baseline characteristics and outcomes of young patients with CAD. METHODS: We retrospectively enrolled patients aged < 40 years of age who underwent coronary angiography in a tertiary hospital in Taiwan between 2002 and 2015. The baseline characteristics and in-hospital outcomes of patients with acute coronary syndrome (ACS) and occlusive CAD (stenotic lesions > 50%) were compared with those of patients without ACS and non-occlusive CAD, respectively. RESULTS: We enrolled 245 young patients including 131 (53.5%) with ACS and 178 with occlusive CAD. The median age of the patients was 36.08 years and the mean follow-up period was 4.84 years. Of all study subjects, 220 (89.8%) were men and 140 (57.1%) were current smokers; there was an overall in-hospital mortality rate of 3.3%. Furthermore, age, body mass index, smoking, total leukocyte count, neutrophil-to-lymphocyte ratio, total cholesterol, and low-density lipoprotein were higher in patients with ACS and significant CAD than in those without ACS and nonstenotic CAD. Interestingly, triglyceride (TG) levels and the TG to high-density lipoprotein ratio were significantly higher in patients with ACS and occlusive CAD than in those without ACS and non-occlusive CAD. Logistic regression analysis revealed that smoking is an independent predictor of ACS and occlusive CAD. CONCLUSIONS: Our findings suggest that classical risk factors, obesity, and inflammation remain potent contributors to occlusive CAD and ACS in young adults in Taiwan. Efforts to prevent or minimize these risk factors, such as smoking cessation and aggressive lipid control, are necessary in young adults.

JNK/AP-1 activation contributes to tetrandrine resistance in T-cell acute lymphoblastic leukaemia.

T-cell acute lymphoblastic leukaemia (T-ALL) is a challenging malignancy with a high relapse rate attributed to drug resistance. Tetrandrine (TET), a bisbenzylisoquinoline alkaloid extracted from a Chinese herb, is a potential anti-cancer and anti-leukaemic drug. In this study we investigated the mechanisms of TET resistance in T-ALL cells in vitro. Among the four T-ALL cell lines tested, Jurkat and CEM cells exhibited the lowest and highest resistance to TET with IC50 values at 24 h of 4.31±0.12 and 16.53±3.32 µmol/L, respectively. When treated with TET, the activity of transcription factor activator protein 1 (AP-1) was significantly decreased in Jurkat cells but nearly constant in CEM cells. To avoid cell-specific variation in drug resistance and transcription factor activities, we established a TET-R Jurkat subclone with the estimated IC50 value of 10.90±.92 µmol/L by exposing the cells to increasing concentrations of TET. Interestingly, when treated with TET, TET-R Jurkat cells exhibited enhanced AP-1 and NF-κB activity, along with upregulation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) signaling pathways, whereas the expression of P-gp was not altered. Selective inhibition of JNK but not ERK suppressed AP-1 activity and TET resistance in TET-R Jurkat cells and in CEM cells. These results demonstrate that Jurkat cells acquire TET resistance through activation of the JNK/AP-1 pathway but not through P-gp expression. The JNK/AP-1 pathway may be a potential therapeutic target in relapsed T-ALL.

Prognostic impact of restored sinus rhythm in patients with sepsis and new-onset atrial fibrillation.

BACKGROUND: New-onset atrial fibrillation (NeOAF) is a common type of tachyarrhythmia in critically ill patients and is associated with increased mortality in patients with sepsis. However, the prognostic impact of restored sinus rhythm (SR) in septic patients with NeOAF remains unclear. METHODS: A total of 791 patients with sepsis, who were admitted to a medical intensive care unit from January 2011 to January 2014, were screened. NeOAF was detected by continuous electrocardiographic monitoring. Patients were categorized into three groups: no NeOAF, NeOAF with restored SR (NeOAF to SR), and NeOAF with failure to restore SR (NeOAF to atrial fibrillation (AF)). The endpoint of this study was in-hospital mortality. Patients with pre-existing AF were excluded. RESULTS: We reviewed the data of 503 eligible patients, including 263 patients with no NeOAF and 240 patients with NeOAF. Of these 240 patients, SR was restored in 165 patients, and SR could not be restored in 75 patients. The NeOAF to AF group had the highest in-hospital mortality rate of 61.3% compared with the NeOAF to SR and no NeOAF groups (26.1% and 17.5%, respectively). Moreover, multivariate logistic regression analysis revealed that failure of restored SR was independently associated with increased in-hospital mortality in patients with sepsis and NeOAF. CONCLUSIONS: Failure to restore a sinus rhythm in patients with new-onset atrial fibrillation may be associated with increased in-hospital mortality in patients with sepsis. Further prospective studies are needed to clarify the effects of restoration of sinus rhythm on survival in patients with sepsis and new-onset atrial fibrillation.

Gentiana scabra Reduces SR-A Expression and Oxidized-LDL Uptake in Human Macrophages.

BACKGROUND: Macrophages can imbibe low-density lipoprotein (LDL) through scavenger receptors to become foam cells, which is critical in the initiation and progression of atherosclerosis. Mounting evidence suggests that the anti-inflammatory nature of Chinese herbs have the capacity to halt the complex mechanisms underlying atherosclerosis. This study examined the effects of Chinese herbs on foam cell formation. METHODS: Chinese herbs were obtained from the Sun Ten pharmaceutic company. Using oxidized LDL (OxLDL) uptake and a cell toxicity assay, we screened more than 30 types of Chinese herbs. Western blotting was used to determine expressions of scavenger receptors (SRs) and extracellular-signal-regulated kinase (ERK) activities. RESULTS: We found that Gentiana scabra reduced oxidized LDL uptake effectively in THP-1 macrophages (p < 0.05 vs. OxLDL treated control). Moreover, treatment with Gentiana scabra in THP-1 macrophages resulted in decreased expression of scavenger receptor- A (SR-A) (p < 0.05 vs. control). Molecular investigation revealed that Gentiana scabra inhibited SR-A protein expression, possibly by regulating ERK signaling pathways (p < 0.05 vs. control). CONCLUSIONS: By regulating SR-A expression, Gentiana scabra reduced oxidized LDL uptake in human macrophages. These results support the potential use of Gentiana scabra in treating atherosclerosis.

Chest Pain with Normal Thallium-201 Myocardial Perfusion Image - Is It Really Normal?

BACKGROUND: Thallium-201 myocardial perfusion image (MPI) is commonly used to detect coronary artery disease in patients with chest pain. Although a normal thallium-201 MPI result is generally considered to be a good prognosis and further coronary angiogram is not recommended, there are still a few patients who suffer from unexpected acute coronary events. The aim of this study was to investigate the clinical prognosis in patients with normal thallium-201 MPI. METHODS: From January 2006 to August 2012, a total 22,003 patients undergoing thallium-201 MPI in one tertiary center were screened. Of these, 8092 patients had normal results and were investigated retrospectively. During follow-up, 54 patients underwent coronary angiogram because of refractory typical angina pectoris or unexpected acute coronary events. These 54 patients were divided into 2 groups: group I consisted of 26 (48.1%) patients with angiography-proven significant coronary artery stenosis, and group II consisted of 28 (51.9%) patients without significant stenosis. RESULTS: Patients in group I had a higher prevalence of prior coronary stenting and electrocardiographic features of ST depression compared with patients in group II. The multivariate analysis demonstrated that both prior coronary stenting and ST depression were risk predictors of unexpected acute coronary events in the patients with normal thallium-201 MPI [odds ratio (OR), 5.93; 95% confidence interval (CI): 1.03-34.06, p = 0.05 and OR, 7.10; 95% CI: 1.28-39.51, p = 0.03,respectively]. CONCLUSIONS: Although there is a low incidence of unexpected acute coronary events in patients with chest pain and normal thallium-201 MPI, physicians should be aware of the potentials risk in certain patients in this specific population.

The Prognostic Role of QTc Interval in Acute Myocarditis.

BACKGROUND: Acute myocarditis is an inflammatory disease of the myocardium. Although a fulminant course of the disease is difficult to predict, it may lead to acute heart failure and death. Previous studies have demonstrated that reduced left ventricular systolic function and prolonged QRS duration can predict the fulminant course of acute myocarditis. This study aimed to identify whether prolonged QTc interval could also be predictive of fulminant disease in this population. METHODS: We retrospectively included 40 patients diagnosed with acute myocarditis who were admitted to our hospital between 2002 and 2013. They were divided into the fulminant group (n = 9) and the non-fulminant group (n = 31). Clinical symptoms, laboratory findings, electrocardiographic, and echocardiographic parameters were analyzed. Multivariate logistic regression analysis was used to identify the independent factors predictive of fulminant disease. RESULTS: Patients with fulminant myocarditis had a higher mortality rate than those with non-fulminant disease (55.6% vs. 0%, p < 0.001). Multivariate analysis revealed that wider QRS durations (133.22 ± 45.85 ms vs. 92.81 ± 15.56 ms, p = 0.030) and longer QTc intervals (482.78 ± 69.76 ms vs. 412.00 ± 33.31 ms, p = 0.016) were significant predictors associated with a fulminant course of myocarditis. CONCLUSIONS: Prolonged QRS duration and QTc interval, upon patient admission, may be associated with an increased risk of fulminant disease and increased in-hospital mortality. Therefore, early recognition of fulminant myocarditis and early mechanical support could provide improved patient outcomes. KEY WORDS: Fulminant myocarditis • Predictors • QRS complex • QTc interval.

Cell response on the biomimetic scaffold of silicon nano- and micro-topography.

Silicon scaffolds were synthesized in a low-pressure furnace via a vapor-liquid-solid (VLS) mechanism. Structural dimensions of silicon scaffolds were tunable in the synthesis to satisfy diverse requirements for cell culture applications. Cylindraceous SiNWs structurally resemble fibrous proteins in connective tissue and the extracellular matrix (ECM), which are main cell adhesion substrata in vivo. Hemispherical silicon microbroccolis (SiMBs) possess large contact area with microscale topology for cell contact and attachment. Mouse 3T3 fibroblasts were cultured on microscale and nanoscale silicon structures with different surface modifications. Silicon scaffolds were functionalized by several physical and chemical vapor deposition methods to modify scaffold surface physical and chemical properties. Metal-coated SiNWs and SiMBs had been demonstrated and compared for their ability to provide mechanical support sites for cell adhesion and promote cell proliferation and maintain normal cell functionality. Scanning electron microscopy (SEM) micrographs at high magnification show cell-scaffold interactions, and immunofluorescence images reveal nuclear DNAs and actin cytoskeleton distribution on nanostructure covered substrates and selected biomarker expression was analyzed by enzyme-linked immunosorbent assay (ELISA).

Therapeutic modification of arterial stiffness: An update and comprehensive review.

Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with long-term worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovascular risk. Additionally to life style modifications, long-term ω-3 fatty acids (fish oil) supplementation in diet may improve arterial stiffness in the population with hypertension or metabolic syndrome. Pharmacological treatment such as renin-angiotensin-aldosterone system antagonists, metformin, and 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors were useful in individuals with hypertension and diabetes. In obese population with obstructive sleep apnea, weight reduction, aerobic exercise, and continuous positive airway pressure treatment may also improve arterial stiffness. In the populations with chronic inflammatory disease such as rheumatoid arthritis, a use of antibodies against tumor necrosis factor-alpha could work effectively. Other therapeutic options such as renal sympathetic nerve denervation for patients with resistant hypertension are investigated in many ongoing clinical trials. Therefore our comprehensive review provides knowledge in detail regarding many aspects of pathogenesis, measurement, and management of arterial stiffness in several populations, which would be helpful for physicians to make clinical decision.

Modulation of both activator protein-1 and nuclear factor-kappa B signal transduction of human T cells by amiodarone.

Amiodarone, a common and effective antiarrhythmic drug, has been reported to have anti-inflammatory effects such as reducing the activation and movement of neutrophils. However, its effects on human T cells remain unclear. The aim of this study was to elucidate the effects and possible underlying mechanisms of amiodarone on human T cells. We isolated human primary T cells from the peripheral blood of healthy volunteers and performed enzyme-linked immunosorbent assay (ELISA), flow cytometry, electrophoretic mobility shift assay, luciferase assay, and Western blotting to evaluate the modulatory effects of amiodarone on human T cells. We found that amiodarone dose dependently inhibited the production of cytokines, including interleukin-2 (IL-2), IL-4, tumor necrosis factor-alpha, and interferon-gamma in activated human T cells. By flow cytometry, we demonstrated that amiodarone suppressed the expression of IL-2 receptor-alpha (CD25) and CD69, the cell surface markers of activated T cells. Moreover, molecular investigations revealed that amiodarone down-regulated activator protein-1 (AP-1) and nuclear factor kappa-B (NF-κB) DNA-binding activities in activated human T cells and also inhibited DNA binding and transcriptional activities of both AP-1 and NF-κB in Jurkat cells. Finally, by Western blotting, we showed that amiodarone reduced the activation of c-Jun NH(2)-terminal protein kinase and P38 mitogen-activated protein kinase, and suppressed stimuli-induced I-kappa B-alpha degradation in activated human T cells. Through regulation of AP-1 and NF-κB signaling, amiodarone inhibits cytokine production and T cell activation. These results show the pleiotropic effects of amiodarone on human T cells and suggest its therapeutic potential in inflammation-related cardiovascular disorders.

A salicylate-based small molecule HS-Cm exhibits immunomodulatory effects and inhibits dipeptidyl peptidase-IV activity in human T cells.

Activated T cells are key players in chronic inflammatory diseases, including atherosclerosis. Salicylates, like aspirin, display not only anti-inflammatory, anti-thrombotic, anti-atherosclerotic activities, but also immunomodulatory effects in T cells at high dosages. Here, we aimed to identify potent immunomodulators for T cells through cell-based screening from a mini-library of 300 salicylate-based small molecules, and elucidate the mechanisms. Human peripheral blood T cells were isolated from buffy coat. Phorbol 12-myristate 13-acetate plus ionomycin (P/I) was used to stimulate T cells. Cytokine production was measured by enzyme-linked immunosorbent assays. T cell activation markers were determined by flow cytometry. The activation of transcription factors and kinases was analyzed by western blotting, electrophoretic mobility shift assay, or kinase assay. Through library screening, we identified a small molecule named HS-Cm [C13H9ClFNO2; N-(4-chloro-2-fluorophenyl)-2-hydroxybenzamide] that exhibited potent immunomodulatory effects on T cells with low cytotoxicity. In P/I-stimulated T cells, HS-Cm inhibited the production of interleukin-2, tumor necrosis factor-alpha, and interferon-gamma and suppressed the expression of surface activation markers CD25, CD69, and CD71, but not CD45RO. HS-Cm down-regulated DNA-binding activities of activator protein-1 and nuclear factor-kappa B, but not nuclear factor of activated T-cells, through inhibiting c-Jun N-terminal kinase/p38 and inhibitor of kappaB alpha (IκBα) kinase (IKK)/IκBα pathways, respectively. On the basis of structure-activity relationship, HS-Cm exerted considerable inhibition of dipeptidyl-peptidase IV/CD26 activity in T cells. Our results suggested that the small molecule HS-Cm exhibiting immunomodulatory effects on T cells may be useful for therapeutics in chronic inflammatory diseases, like atherosclerosis, diabetes and autoimmune arthritis.