Cinnamaldehyde inhibits the NLRP3 inflammasome by preserving mitochondrial integrity and augmenting autophagy in Shigella sonnei-infected macrophages.

BACKGROUND: Worldwide, more than 125 million people are infected with Shigella each year and develop shigellosis. In our previous study, we provided evidence that Shigella sonnei infection triggers activation of the NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome in macrophages. NLRP3 inflammasome is responsible for regulating the release of the proinflammatory cytokines interleukin (IL)-1ß and IL-18 through the protease caspase-1. Researchers and biotech companies have shown great interest in developing inhibitors of the NLRP3 inflammasome, recognizing it as a promising therapeutic target for several diseases. The leaves of Cinnamomum osmophloeum kaneh, an indigenous tree species in Taiwan, are rich in cinnamaldehyde (CA), a compound present in significant amounts. Our aim is to investigate how CA affects the activation of the NLRP3 inflammasome in S. sonnei-infected macrophages. METHODS: Macrophages were infected with S. sonnei, with or without CA. ELISA and Western blotting were employed to detect protein expression or phosphorylation levels. Flow cytometry was utilized to assess H2O2 production and mitochondrial damage. Fluorescent microscopy was used to detect cathepsin B activity and mitochondrial ROS production. Additionally, colony-forming units were employed to measure macrophage phagocytosis and bactericidal activity. RESULTS: CA inhibited the NLRP3 inflammasome in S. sonnei-infected macrophages by suppressing caspase-1 activation and reducing IL-1ß and IL-18 expression. CA also inhibited pyroptosis by decreasing caspase-11 and Gasdermin D activation. Mechanistically, CA reduced lysosomal damage and enhanced autophagy, while leaving mitochondrial damage, mitogen-activated protein kinase phosphorylation, and NF-κB activation unaffected. Furthermore, CA significantly boosted phagocytosis and the bactericidal activity of macrophages against S. sonnei, while reducing secretion of IL-6 and tumour necrosis factor following infection. CONCLUSION: CA shows promise as a nutraceutical for mitigating S. sonnei infection by diminishing inflammation and enhancing phagocytosis and the bactericidal activity of macrophages against S. sonnei.

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.

Dilute Povidone-Iodine Solution Soaking Is Ineffective in Improving Outcomes of Necrotizing Fasciitis Caused by Diabetic Foot.

ABSTRACT: Wound soaking is a physical debridement method that helps reduce bacterial colonization and consequently promotes wound healing. Although soaking in povidone-iodine solution was ineffective in reducing bacterial colonization in acute trauma wounds, there is still a lack of evidence supporting the efficacy of this method in treating severe soft tissue infection. This study aimed to explore the effects of wound soaking in 1% dilute povidone-iodine solution on necrotizing fasciitis caused by diabetic foot ulcers. We retrospectively reviewed and finally included 153 patients who were admitted because of diabetic foot ulcers after undergoing fasciotomy for necrotizing infection from January 2018 to December 2021. Results showed no statistical difference in the outcomes between patients in the soaking and nonsoaking groups. End-stage renal disease (P = 0.029) and high serum C-reactive protein level (P = 0.007) were the only independent factors for below-knee amputation in the univariate and multivariate logistic regression analyses. Therefore, soaking diabetic wounds with severe infection in 1% dilute povidone-iodine solution may not reduce the hospital length of stay, risk of below-knee amputation, and readmission rate.

Risk factors and clinical characteristics associated with a ruptured ectopic pregnancy: A 19-year retrospective observational study.

ABSTRACT: Ectopic pregnancy is the most common cause of maternal mortality in the first trimester of pregnancy. The aim of this study was to find risk factors and clinical characteristics associated with ruptured ectopic pregnancies at a medical center in eastern Taiwan in a 19-year period. This was a retrospective observational study that included patients diagnosed with ectopic pregnancy between August 1999 and December 2018. Data about the demographic variables, initial presentation, pre-treatment beta-human chorionic gonadotropin levels, treatment routes (laparoscopy or laparotomy), surgical methods (salpingostomy or salpingectomy), operation time, blood loss amount, the status of ectopic pregnancy (ruptured or unruptured), the requirement for transfusion, and duration of hospital stay were collected. The categorical and continuous variables were analyzed using the correlation coefficients. This study included 225 women who were diagnosed as having an ectopic pregnancy. There were 49 and 176 women with unruptured and ruptured ectopic pregnancies, respectively. The beta-human chorionic gonadotropin levels, history of previous ectopic pregnancy, pelvic inflammatory disease, tubal surgery, abdominal history, and vaginal bleeding were not significantly different between the 2 groups. The ratio of women with abdominal pain was significantly higher in the ruptured ectopic pregnancy group than in the unruptured group (89.1% vs. 63.8%, respectively, P < .001). Preoperative hemoglobin was lower in the ruptured group compared with the unruptured group (P < .001). Blood loss, postoperative hemoglobin, and blood transfusion were significantly higher in the ruptured group than in the unruptured group (P = .000 and P = .001 for blood loss and blood transfusion, respectively). Multiple logistic regression analysis revealed that abdominal pain and blood loss were associated with ruptured tubal pregnancies (adjusted odds ratio [95% confidence intervals]: 3.42 {1.40, 8.40}; 1.01 {1.005, 1.014}, respectively). In conclusion, early pregnancy with abdominal pain, more parity, and lower preoperative hemoglobin should be aware of the possibility of ruptured ectopic pregnancy. More blood loss, transfusion and lower postoperative hemoglobin were also noted with ruptured ectopic pregnancy.

Treatment with angiotensin receptor neprilysin inhibitor for Taiwan heart failure patients: Rationale and baseline characteristics of the TAROT-HF study.

BACKGROUND: This study used a real-world database to investigate the prescription patterns of sacubitril/valsartan (Sac/Val) among Taiwanese patients with heart failure with reduced ejection fraction (HFrEF). METHODS: The Treatment with Angiotensin Receptor neprilysin inhibitor fOr Taiwan Heart Failure patients (TAROT-HF) study is a principal investigator-initiated, multicenter, observational, retrospective study on Taiwanese HFrEF patients. A total of 1772 patients with HFrEF (mean age 62.5 years, 75.3% male, mean left ventricular ejection fraction [LVEF] 29.3%) who received Sac/Val at 10 hospitals between 2017 and 2018 were enrolled at the date of Sac/Val initiation. Among these patients, 585 (33%) initially received Sac/Val during acute decompensated heart failure (HF) hospitalization (TAROT-AHF arm), whereas 1187 (67%) initially received the same at the outpatient clinic (TAROT-CHF arm). RESULTS: A total of 1343 (75.8%) patients received an initial dose of 50 mg twice daily or fewer, whereas 422 (23.8%) received the standard initiation dose (100 mg twice daily). During outpatient Sac/Val initiation, the mean dosages were significantly higher than that following hospitalization (117 ± 55 mg vs 109 ± 57 mg; p = 0.014). Multivariate analysis identified younger age, higher systolic blood pressure, higher LVEF, prior use of renin-angiotensin system inhibitors, use of ivabradine, and a history of diabetes mellitus as independent factors for initiating a standard Sac/Val dose. Over a follow-up period of 18 months, incidences of cardiovascular death or first unplanned HF hospitalization were 18.69 and 33.11 per 100-person years for the TAROT-CHF and TAROT-AHF arms, respectively. CONCLUSION: The TAROT-HF study provided an opportunity to describe the clinical features of patients with HFrEF who received Sac/Val, assess the real-world utilization and efficacy of Sac/Val, and compare these patients with those included in prior registries.

Evaluation of the virucidal effects of rosmarinic acid against enterovirus 71 infection via in vitro and in vivo study.

BACKGROUND: Although enterovirus 71 (EV71) is an important public health threat, especially in the Asia-Pacific region, there are still no effective drugs or vaccines to treat and prevent EV71 infection. Therefore, it is critical to develop prophylactic and therapeutic agents against EV71. Rosmarinic acid (RA), a phytochemical, has been discovered to possess a broad spectrum of biological activities. METHODS: The virucidal effects of RA on EV71 were determined by MTT, western blot, median cell culture infectious dose, apoptosis detection, plaque reduction, semi-quantitative real-time polymerase chain reaction, immunofluorescence detection, molecular docking analysis, and mouse protection assay. RESULTS: RA showed a strong protective effect against EV71 infection in human rhabdomyosarcoma cells when the multiplicity of infection was 1, with a low IC50 value (4.33 ± 0.18 µM) and high therapeutic index (340). RA not only protected cells from EV71-induced cytopathic effects, but also from EV71-induced apoptosis. The results of time-of-addition analysis demonstrated that the inhibitory activity of RA was highest at the early stage of viral infection. Consistent with this, the infectivity of EV71 in the early stage of viral infection also was observed to be limited in neonatal mice treated with RA. Further, molecular docking predicts that RA could replace the natural pocket factor within the VP1 capsid-binding hydrophobic pocket. CONCLUSIONS: This study suggests that RA has the potential to be developed as an antiviral agent against initial EV71 infection to prevent or reduce EV71-induced pathogenesis and complications, since RA can effectively reduce EV71 infection in the early stages of viral infection.

Mechanistic Insight Into the Activation of the NLRP3 Inflammasome by Neisseria gonorrhoeae in Macrophages.

Gonorrhea is a type III legal communicable disease caused by Neisseria gonorrhoeae (NG), one of the most common sexually transmitted bacteria worldwide. NG infection can cause urethritis or systemic inflammation and may lead to infertility or other complications. The NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome is a protein complex composed of NLRP3, apoptosis-associated speck-like protein and caspase-1 and is an important part of the cellular machinery controlling the release of interleukin (IL)-1ß and IL-18 and the pathogenesis of numerous infectious diseases. It has been reported that NG infection activates the NLRP3 inflammasome; however, the underlying mechanism remain unclear. In this report, the signaling pathways involved in the regulation of NG-mediated NLRP3 inflammasome activation in macrophages were studied. The results indicated that viable NG, but not heat-killed or freeze/thaw-killed NG, activated the NLRP3 inflammasome in macrophages through toll-like receptor 2, but not toll-like receptor 4. NG infection provided the priming signal to the NLRP3 inflammasome that induced the expression of NLRP3 and IL-1ß precursor through the nuclear factor kappa B and mitogen-activated protein kinase pathways. In addition, NG infection provided the activation signal to the NLRP3 inflammasome that activated caspase-1 through P2X7 receptor-dependent potassium efflux, lysosomal acidification, mitochondrial dysfunction, and reactive oxygen species production pathways. Furthermore, we demonstrated that NLRP3 knockout increased phagocytosis of bacteria by macrophages and increases the bactericidal activity of macrophages against NG. These findings provide potential molecular targets for the development of anti-inflammatory drugs that could ameliorate NG-mediated inflammation.

A Novel Protective Function of 5-Methoxytryptophan in Vascular Injury.

5-Methoxytryptophan (5-MTP), a 5-methoxyindole metabolite of tryptophan metabolism, was recently shown to suppress inflammatory mediator-induced cancer cell proliferation and migration. However, the role of 5-MTP in vascular disease is unknown. In this study, we investigated whether 5-MTP protects against vascular remodeling following arterial injury. Measurements of serum 5-MTP levels in healthy subjects and patients with coronary artery disease (CAD) showed that serum 5-MTP concentrations were inversely correlated with CAD. To test the role of 5-MTP in occlusive vascular disease, we subjected mice to a carotid artery ligation model of neointima formation and treated mice with vehicle or 5-MTP. Compared with vehicle-treated mice, 5-MTP significantly reduced intimal thickening by 40% 4 weeks after ligation. BrdU incorporation assays revealed that 5-MTP significantly reduced VSMC proliferation both in vivo and in vitro. Furthermore, 5-MTP reduced endothelial loss and detachment, ICAM-1 and VCAM-1 expressions, and inflammatory cell infiltration in the ligated arterial wall, suggesting attenuation of endothelial dysfunction. Signaling pathway analysis indicated that 5-MTP mediated its effects predominantly via suppressing p38 MAPK signaling in endothelial and VSMCs. Our data demonstrate a novel vascular protective function of 5-MTP against arterial injury-induced intimal hyperplasia. 5-MTP might be a therapeutic target for preventing and/or treating vascular remodeling.

Resveratrol, a red wine antioxidant, reduces atrial fibrillation susceptibility in the failing heart by PI3K/AKT/eNOS signaling pathway activation.

BACKGROUND: Resveratrol has shown benefits in reducing ventricular remodeling and arrhythmias. OBJECTIVE: This study aimed to assess the therapeutic efficacy of resveratrol in reducing atrial fibrillation (AF) in a heart failure (HF) model and to explore the underlying mechanisms. METHODS: HF rabbits were created 4 weeks after undergoing coronary ligation. Group 1 (n = 6) was divided into subgroups of (a) normal rabbits, (b) HF sham rabbits, and (c) HF rabbits treated for 1 week with intraperitoneal injections of resveratrol, (d) resveratrol plus wortmannin, or (e) resveratrol plus diphenyleneiodonium chloride (DPI). All rabbits underwent epicardial catheter stimulation. Collagen content, messenger RNA and protein expression in ion channels, and phosphoinositide 3-kinase (PI3K)/AKT/endothelial nitric oxide synthase (eNOS) signaling pathways were studied in left atrial appendage (LAA) preparations. To investigate acute drug effects on left atrial electrophysiology, groups 2 a through 2e (n = 6 per group) were subjected to Langendorff perfusion. RESULTS: Higher AF inducibility was found in the HF group and groups that were given PI3K and eNOS inhibitors than in the normal and resveratrol-treated groups (P < .001). Histologic analysis of the LAA revealed a decrease in fibrosis in resveratrol-treated groups compared with the HF group (8.95% ± 1.53% vs 26.62% ± 2.19%, P < .001). In real-time polymerase chain reaction analysis, ion channels including Kv1.4, Kv1.5, KvLQT1, Kir2.1, Nav1.5, Cav1.2, NCX, SERCA2a, and phospholamban were upregulated by resveratrol. PI3K, AKT, and eNOS messenger RNA and protein expression were upregulated by resveratrol but were inhibited by the coadministration of wortmannin and DPI. CONCLUSION: Resveratrol decreases left atrial fibrosis and regulates variation in ion channels to reduce AF through the PI3K/AKT/eNOS signaling pathway.

Seasonal variation in the frequency of sudden cardiac death and ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy: the effect of meteorological factors.

BACKGROUND: Sudden cardiac death (SCD) is the most catastrophic presentation in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). OBJECTIVES: To investigate the seasonal variations in the frequency of SCD and ventricular tachyarrhythmia in patients with AVRD/C and to elucidate the meteorological factors that trigger these events. METHODS: From 1998 to 2012, we enrolled 88 consecutive patients with ARVD/C from Taipei City. The cohort included 20 living patients who received implantable cardioverter-defibrillator (ICD) and 68 autopsied patients with SCD from the Taiwan National Forensic Institute registry. The baseline clinical characteristics, seasonal distribution, and associated meteorological factors were explored to predict the occurrences of events, which include appropriate ICD interventions and SCD. RESULTS: There were 106 events, including 38 (35.8%, 1.9 episodes per patient) appropriate ICD interventions in living patients with ARVD/C and 68 (64.2%) SCD events. The seasonal peak occurred predominantly in summer (P < .05) in both groups. For meteorological factors, the onset of event was associated with higher average daily temperature and longer sunshine duration. The variation in humidity within 3 days of events was significantly increased. After multivariate logistic regression analysis, higher average daily temperature and larger variation in humidity were associated with increase in events (odds ratio 1.23, 95% confidence interval 1.16-1.31, P < .001, and odds ratio 1.19, 95% confidence interval 1.15-1.23, P < .001, respectively). CONCLUSIONS: There was seasonal variation with a summer peak in the occurrence of ventricular arrhythmias and SCD in patients with ARVD/C. Meteorological factors including higher temperature and larger variation in humidity within 3 days of events were independently associated with the development of events.

Mesenchymal stem cells from human umbilical cord express preferentially secreted factors related to neuroprotection, neurogenesis, and angiogenesis.

Mesenchymal stem cells (MSCs) are promising tools for the treatment of diseases such as infarcted myocardia and strokes because of their ability to promote endogenous angiogenesis and neurogenesis via a variety of secreted factors. MSCs found in the Wharton's jelly of the human umbilical cord are easily obtained and are capable of transplantation without rejection. We isolated MSCs from Wharton's jelly and bone marrow (WJ-MSCs and BM-MSCs, respectively) and compared their secretomes. It was found that WJ-MSCs expressed more genes, especially secreted factors, involved in angiogenesis and neurogenesis. Functional validation showed that WJ-MSCs induced better neural differentiation and neural cell migration via a paracrine mechanism. Moreover, WJ-MSCs afforded better neuroprotection efficacy because they preferentially enhanced neuronal growth and reduced cell apoptotic death of primary cortical cells in an oxygen-glucose deprivation (OGD) culture model that mimics the acute ischemic stroke situation in humans. In terms of angiogenesis, WJ-MSCs induced better microvasculature formation and cell migration on co-cultured endothelial cells. Our results suggest that WJ-MSC, because of a unique secretome, is a better MSC source to promote in vivo neurorestoration and endothelium repair. This study provides a basis for the development of cell-based therapy and carrying out of follow-up mechanistic studies related to MSC biology.

Differential expression of distinct surface markers in early endothelial progenitor cells and monocyte-derived macrophages.

Bone marrow-derived endothelial progenitor cells (EPCs) play a fundamental role in postnatal angiogenesis. Currently, EPCs are defined as early and late EPCs based on their biological properties and their time of appearance during in vitro culture. Reports have shown that early EPCs share common properties and surface markers with adherent blood cells, especially CD14+ monocytes. Distinguishing early EPCs from circulating monocytes or monocyte-derived macrophages (MDMs) is therefore crucial to obtaining pure endothelial populations before they can be applied as part of clinical therapies. We compared the gene expression profiles of early EPCs, blood cells (including peripheral blood mononuclear cells, monocytes, and MDMs), and various endothelial lineage cells (including mature endothelial cells, late EPCs, and CD133+ stem cells). We found that early EPCs expressed an mRNA profile that showed the greatest similarity to MDMs than any other cell type tested. The functional significance of this molecular profiling data was explored by Gene Ontology database search. Novel plasma membrane genes that might potentially be novel isolation biomarkers were also pinpointed. Specifically, expression of CLEC5A was high in MDMs, whereas early EPCs expressed abundant SIGLEC8 and KCNE1. These detailed mRNA expression profiles and the identified functional modules will help to develop novel cell isolation approaches that will allow EPCs to be purified; these can then be used to target cardiovascular disease, tumor angiogenesis, and various ischemia-related diseases.

Magnesium lithospermate B mediates anti-inflammation targeting activator protein-1 and nuclear factor-kappa B signaling pathways in human peripheral T lymphocytes.

The activation of T lymphocytes contributes to the inflammatory processes of atherosclerotic diseases. Danshen is a traditional Chinese medicine and has shown therapeutic effects in patients with cardiovascular and cerebrovascular diseases. We investigated the effects of aqueous extract of Danshen (magnesium lithospermate B (MLB)) on phorbol 12-myristate acetate+ionomycin and anti-CD3+anti-CD28 monoclonal antibody-activated T cells. We showed that MLB inhibited interleukin (IL)-2, IL-4, tumor necrosis factor-alpha and interferon-gamma production from activated T cells. The expressions of T cell activation markers CD 25 and CD 69 were effectively reduced. EMSA analysis indicated that MLB down-regulated activator protein-1 (AP-1), nuclear factor kappa B (NF-κB) and octamer binding transcription factor (Oct-1) DNA-binding activity. In addition, MLB inhibited c-jun N-terminal kinase (JNK) but not extracellular signal regulated protein kinase activity. MLB also inhibited IκBα degradation, nuclear translocation of p65 and p50 as well as decreased IκBα kinase (IKK) activity. Through suppressing JNK-AP-1, IKK-IκBα-NF-κB and Oct-1 signaling pathways by MLB in activated T cells, our results provide support for efficacy of MLB in inflammatory diseases and raise its therapeutic potential in activated T cell-mediated pathologies.

[Value of 16-slice spiral CT in the diagnosis of tumor-like bronchial tuberculosis].

OBJECTIVE: To evaluate the value of 16-slice multi-detector CT (MDCT) in the diagnosis of tumor-like bronchial tuberculosis. METHODS: Twenty-five patients with tumor-like bronchial tuberculosis underwent 16-slice CT scanning and the CT data were analyzed. RESULTS: Tumor-like bronchial tuberculosis were classified into 4 types according to the imaging features, namely intra-lumen nodule, intra-lumen mass, compression from outside of the bronchial lumens, and lung hilum mass. Tumor-like bronchial tuberculosis was featured by irregular bronchial wall thickening which led to decreased internal diameter of the bronchi with the external diameter remaining unchanged, ring-shaped enhancement, and absence of clear boundaries between the lesion and normal bronchi. CONCLUSION: 16-slice MDCT can be advantageous in displaying tumor-like bronchial tuberculosis, and axial scan with 16-slice spiral CT combined with image reconstruction allows detection of the lesions inside the trachea and bronchus.