Four-Component Radical 1,2-Selenosulfonylation of Allenes.

Selenosulfones, as pivotal pharmaceutical molecule frameworks, have become a research hotspot in modern organic synthesis due to their vital need for efficient preparation. Herein, we have developed an iron-catalyzed four-component controllable radical tandem reaction of allenes involving cycloketone oxime esters, 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct (DABSO), and diphenyl diselenides for the synthesis of complex selenosulfones. This is the first case of achieving the 1,2-selenosulfonylation of allenes via a radical process, wherein precise control of radical rates and polarity matching enhance high regioselective conversion. The reaction conditions are ecofriendly and mild with step-efficiency by forming two new C-S bonds and one C-Se bond in one pot. Moreover, the 1,2-selenosulfonylation of allenes can be achieved by replacing cycloketone oxime esters with aryldiazonium tetrafluoroborates in this system.

Anatomical characteristics of aortic valve diseases: Implications for transcatheter aortic valve replacement.

Background: The etiology of aortic stenosis (AS) significantly impacts transcatheter heart valve (THV) implantation, with rheumatic etiology posing challenges. The concept of valve anchoring during transcatheter aortic valve replacement (TAVR) for patients with aortic regurgitation (AR) remains unclear. Objective: This study aims to investigate the clinical and CT anatomical characteristics of various aortic valve diseases. Methods: A retrospective analysis was conducted on consecutive patients who underwent CT for severe aortic diseases between April 2019 and February 2023. CT analysis was performed in eight anatomical landmarks: left ventricular outflow tract (LVOT), aortic annulus, sinus of Valsalva (SOV), sinotubular junction (STJ), ascending aorta (AAO), coronary height, aortic angle, and aortic valve calcification volume. Results: 121 patients with severe aortic valve disease were included, divided into AS (71 cases, 59%) and AR (50 cases, 41%) groups. In patients with AR, the absolute diameters of the annulus, LVOT, SOV, STJ, and AAO, as well as the heights of SOV and STJ and the cardiac angle, are larger than those in patients with AS (all P < 0.05). In normalized aortic root dimensions, the AR group had a higher SOV and STJ diameter-to-annulus ratio than the AS group (STJ-SOV-annulus: 1.51-1.44-1.00 vs 1.33-1.28-1.00). The bicuspid and rheumatic AS groups had smaller sinuses (STJ-SOV-annulus:1.27-1.35-1.00, 1.17-1.30-1.00, respectively), necessitating the downsizing of the THV. For 74% of AR patients, the sinotubular junction could not be used as a second anchoring zone, and anchoring relied primarily on the annulus. Conclusions: Patients with rheumatic etiology require smaller valves, and anchoring in AR patients depends on the valve annulus. These structural characteristics will influence TAVR selection.

Mechanism Analysis of Vascular Calcification Based on Fluid Dynamics.

Vascular calcification is the abnormal deposition of calcium phosphate complexes in blood vessels, which is regarded as the pathological basis of multiple cardiovascular diseases. The flowing blood exerts a frictional force called shear stress on the vascular wall. Blood vessels have different hydrodynamic properties due to discrepancies in geometric and mechanical properties. The disturbance of the blood flow in the bending area and the branch point of the arterial tree produces a shear stress lower than the physiological magnitude of the laminar shear stress, which can induce the occurrence of vascular calcification. Endothelial cells sense the fluid dynamics of blood and transmit electrical and chemical signals to the full-thickness of blood vessels. Through crosstalk with endothelial cells, smooth muscle cells trigger osteogenic transformation, involved in mediating vascular intima and media calcification. In addition, based on the detection of fluid dynamics parameters, emerging imaging technologies such as 4D Flow MRI and computational fluid dynamics have greatly improved the early diagnosis ability of cardiovascular diseases, showing extremely high clinical application prospects.

Screening of immune-related secretory proteins linking chronic kidney disease with calcific aortic valve disease based on comprehensive bioinformatics analysis and machine learning.

BACKGROUND: Chronic kidney disease (CKD) is one of the most significant cardiovascular risk factors, playing vital roles in various cardiovascular diseases such as calcific aortic valve disease (CAVD). We aim to explore the CKD-associated genes potentially involving CAVD pathogenesis, and to discover candidate biomarkers for the diagnosis of CKD with CAVD. METHODS: Three CAVD, one CKD-PBMC and one CKD-Kidney datasets of expression profiles were obtained from the GEO database. Firstly, to detect CAVD key genes and CKD-associated secretory proteins, differentially expressed analysis and WGCNA were carried out. Protein-protein interaction (PPI), functional enrichment and cMAP analyses were employed to reveal CKD-related pathogenic genes and underlying mechanisms in CKD-related CAVD as well as the potential drugs for CAVD treatment. Then, machine learning algorithms including LASSO regression and random forest were adopted for screening candidate biomarkers and constructing diagnostic nomogram for predicting CKD-related CAVD. Moreover, ROC curve, calibration curve and decision curve analyses were applied to evaluate the diagnostic performance of nomogram. Finally, the CIBERSORT algorithm was used to explore immune cell infiltration in CAVD. RESULTS: The integrated CAVD dataset identified 124 CAVD key genes by intersecting differential expression and WGCNA analyses. Totally 983 CKD-associated secretory proteins were screened by differential expression analysis of CKD-PBMC/Kidney datasets. PPI analysis identified two key modules containing 76 nodes, regarded as CKD-related pathogenic genes in CAVD, which were mostly enriched in inflammatory and immune regulation by enrichment analysis. The cMAP analysis exposed metyrapone as a more potential drug for CAVD treatment. 17 genes were overlapped between CAVD key genes and CKD-associated secretory proteins, and two hub genes were chosen as candidate biomarkers for developing nomogram with ideal diagnostic performance through machine learning. Furthermore, SLPI/MMP9 expression patterns were confirmed in our external cohort and the nomogram could serve as novel diagnosis models for distinguishing CAVD. Finally, immune cell infiltration results uncovered immune dysregulation in CAVD, and SLPI/MMP9 were significantly associated with invasive immune cells. CONCLUSIONS: We revealed the inflammatory-immune pathways underlying CKD-related CAVD, and developed SLPI/MMP9-based CAVD diagnostic nomogram, which offered novel insights into future serum-based diagnosis and therapeutic intervention of CKD with CAVD.

Targeting NK-1R attenuates renal fibrosis via modulating inflammatory responses and cell fate in chronic kidney disease.

Background: Renal fibrosis is the final common pathway of chronic kidney disease (CKD), which is clinically irreversible and without effective therapy. Renal tubules are vulnerable to various insults, and tubular injury is involving in the initiation and evolution of renal inflammation and fibrosis. Neurokinin-1 receptor (NK-1R) functions by interacting with proinflammatory neuropeptide substance P (SP), exerting crucial roles in various neurological and non-neurological diseases. However, its roles in renal inflammation and fibrosis are still unknown. Methods: We collected renal biopsy specimens and serum samples of individuals with or without CKD. Additionally, knockout mice lacking NK-1R expression, SP addition and NK-1R pharmacological antagonist treatment in the unilateral ureteral obstruction (UUO) model, and NK-1R-overexpressed HK-2 cells were employed. Results: Renal SP/NK-1R and serum SP were increased in patients with CKD and mice experiencing UUO and correlated with renal fibrosis and function. SP addition enhanced UUO-induced progressive inflammatory responses and renal fibrosis, whereas genetically or pharmacologically targeting NK-1R attenuated these effects. Mechanistically, TFAP4 promoted NK-1R transcription by binding to its promoter, which was abolished by mutation of the binding site between TFAP4 and NK-1R promoter. Furthermore, SP acted through the NK-1R to activate the JNK/p38 pathways to modulate cell fate of tubular epithelial cells including growth arrest, apoptosis, and expression of profibrogenic genes. Conclusion: Our data reveals that SP/NK-1R signaling promotes renal inflammatory responses and fibrosis, suggesting NK-1R could be a potential therapeutic target for the patients with CKD.

The myth of aortic valve annulus changes in aortic valve disease.

Background: The characteristics of aortic annulus changes in aortic regurgitation (AR) patients are poorly understood, and predictive factors among aortic valve disease are yet to be established. Objective: This study seeks to elucidate the pattern of annular size fluctuations across different cardiac phases in AR patients and to identify predictors for annular enlargement during either systole or diastole in aortic valve diseases. Methods: A retrospective analysis was conducted on 55 patients with severe aortic valve diseases, including 26 patients with aortic stenosis (AS) and 29 with AR, to discern the two groups' contrasting and analogous patterns of annular changes. The patient sample was expanded to 107 to investigate the factors influencing the size of the annulus during different cardiac phases. Based on our findings, patients were then divided into two groups: those with an annulus that is larger during systole (83 patients) and those where the annulus is larger during diastole (24 patients). Results: Typically, AR patients exhibit a dynamic annulus, with both perimeter and area being largest during mid-systole. These dimensions diminish progressively and then increase again in early diastole, a pattern consistent with observations in AS patients. Among 107 patients, 21% had diastolic enlargement. Systolic measurements would lead to prosthesis undersizing in 17% of these. Male gender and lower systolic annulus minimum relative to body surface area (AnMin index) were predictors of diastolic enlargement, with ROC curve areas of 0.70 and 0.87 for AR and AS, respectively. Conclusions: Systolic measurements are recommended for AR patients. Gender and the AnMin index are significant predictors, particularly potent in AS patients.

Current Trends and Research Hotspots in Pancreatic Stellate Cells: A Bibliometric Study.

Background: Pancreatic stellate cells (PSCs) play crucial roles in acute/chronic pancreatitis and pancreatic cancer. In this study, bibliometric analysis was used to quantitatively and qualitatively analyze the literature related to PSCs from 1998-2021 to summarize the current trends and research topics in this field. Methods: Relevant literature data were downloaded from the Science Citation Index Expanded Web of Science Core Collection (WoSCC) on April 07, 2021, using Clarivate Analytics. Biblioshiny R packages, VOSviewer, Citespace, BICOMB, gCLUTO, and the Online Analysis Platform of Literature Metrology (http://bibliometric.com) were used to analyze the manually selected data. Results: A total of 958 relevant studies published in 48 countries or regions were identified. The United States of America (USA) had the highest number of publications, followed by the People's Republic of China, Germany, and Japan. Tohoku University (Japan), the University of New South Wales (Australia), the University of Texas MD Anderson Cancer Center (USA), Technical University of Munich (Germany), and University of Rostock (Germany) were the top five institutions with most publications. Nine major clusters were generated using reference co-citation analysis. Keyword burst detection revealed that progression (2016-2021), microenvironment (2016-2021), and tumor microenvironment (2017-2021) were the current frontier keywords. Biclustering analysis identified five research hotspots in the field of PSCs during 1998-2021. Conclusion: In this study, a scientometric analysis of 958 original documents related to PSCs showed that the research topics of these studies are likely in the transition from acute/chronic pancreatitis to pancreatic cancer. The current research trends regarding PSCs are related to pancreatic cancer, such as tumor microenvironment. This study summarizes five research hotspots in the field of PSCs between 1998 and 2021 and thus may provide insights for future research.

Intermittent concurrent use of clopidogrel and proton pump inhibitors did not increase risk of adverse clinical outcomes in Chinese patients with coronary artery disease.

BACKGROUND: Proton pump inhibitors (PPIs) are frequently prescribed to patients with coronary heart disease (CHD) under antiplatelet therapy to prevent gastrointestinal (GI) bleeding. However, its clinical impact is still under debate, especially in Asian population. This study was undertaken to explore the effects of concurrent use of clopidogrel and PPIs on the clinical outcomes in Chinese patients with CHD in secondary prevention. METHODS: A single-center retrospective study was conducted in 638 patients with CHD on consecutive clopidogrel therapy for at least 1 year. After 18-month follow-up, adverse clinical events were collected. Cox regression was used to calculate hazard ratios (HR) and 95% confidence interval (CI) for the effect of PPI use on the outcomes. A total of 638 patients were recruited from 2014 to 2015 in this study, among whom 201 were sustained PPI users, 188 were intermittent PPI users and the remaining 249 were non-PPI users. RESULTS: Compared with sustained PPI users, intermittent use of PPIs was associated with a lower risk of stroke, major adverse cardiac events (MACE) and net adverse clinical event (NACE) (stroke: adjusted HR: 0.109, 95% CI 0.014-0.878, p = 0.037; MACE: adjusted HR: 0.293, 95% CI 0.119-0.722; p = 0.008; NACE: adjusted HR: 0.357, 95% CI 0.162-0.786, p = 0.011). Subgroup analysis further revealed the benefit of intermittent PPI use was significant in male CHD patients over 60 years old, with hypertension or chronic kidney disease, and undergoing percutaneous coronary intervention during hospitalization. CONCLUSION: The current findings suggest that the intermittent concurrent use of PPIs and clopidogrel is not associated with an increased risk of 18-month adverse clinical outcomes, and intermittent use of PPIs is associated with a lower rate of MACE and NACE.

Oxidized low-density lipoprotein inhibits the degradation of cyclophilin A via the lysosome in vascular smooth muscle cells.

BACKGROUND: Cyclophilin A (CyPA) plays an important role in the progression of atherosclerosis. Additionally, it has been reported that lysosomal function is markedly impaired in atherosclerosis induced by oxidized low-density lipoprotein (ox-LDL). As the CyPA degradation pathway remains to be elucidated, we aimed to uncover the role of lysosomes and ox-LDL in the degradation of CyPA. METHODS: We exploited RNA interference (RNAi) in combination with either the lysosomal inhibitor chloroquine (CQ) or the proteasomal inhibitor MG-132 to examine CyPA turnover. We also investigated the role of ox-LDL in lysosomal function and the CyPA degradation pathway and determined whether CyPA interacts with the selective autophagy adaptor p62. RESULTS: CQ markedly reversed the CyPA downregulation induced by RNAi and increased intracellular levels of LC3 and p62. MG-132 significantly suppressed polyubiquitinated protein degradation but did not inhibit RNAi-induced CyPA downregulation. Additionally, neither CQ nor MG-132 influenced the gene-silencing efficiency of CyPA siRNA. Moreover, ox-LDL induced cytosolic accumulation of p62 was inconsistent with increased expression of LC3-II. Meanwhile, ox-LDL inhibited RNAi-induced downregulation of CyPA. Immunofluorescence indicated colocalization of endogenous CyPA with ubiquitin and with p62 in response to CQ treatment, and co-immunoprecipitation analysis confirmed interaction between CyPA and p62. CONCLUSION: CyPA is degraded by a lysosome-dependent pathway that may involve p62-mediated selective autophagy. Furthermore, ox-LDL modulates the degradation of CyPA via its inhibitory role in lysosomes, contributing to increased expression of CyPA in atherosclerotic plaques.

Plasma D-dimer as a predictor of intraluminal thrombus burden and progression of abdominal aortic aneurysm.

AIM: Intraluminal thrombus (ILT) is presented in most abdominal aortic aneurysms (AAAs) and is suggested to promote AAA expansion. D-dimer, a breakdown product in the thrombus remodeling, may have prognostic value for AAA. This study investigated the interrelation between plasma D-dimer level, ILT volume, AAA size and progression. MAIN METHODS: This was a retrospective observational study that involved 181 patients with infra-renal AAA. They were divided into small and large AAA groups according to AAA diameter. 24 of them had repeated abdominal computed tomography angiography (CTA) scan and were divided into slow-growing and fast-growing AAA groups according to the median value of AAA growth rate. Baseline and follow-up plasma D-dimer level, maximum diameter of AAA, total infra-renal aortic volume and ILT volume were analyzed. KEY FINDINGS: Plasma D-dimer level was positively correlated with ILT volume (R = 0.382, P < 0.001) and maximum diameter of AAA (R = 0.442, P < 0.001). Increasing value of plasma D-dimer was positively associated with the accelerated growth rate of AAA (R = 0.720, P < 0.01). ILT volume showed positive correlation with maximum diameter (R = 0.859, P < 0.001) and growth rate of AAA (R = 0.490, P < 0.05). After adjusting the baseline ILT volume, the positive correlations remained to be statistically significant between plasma D-dimer level and AAA size (R = 0.200, P < 0.05), as well as increasing value of plasma D-dimer and growth rate of AAA (R = 0.642, P < 0.05). SIGNIFICANCE: Plasma D-dimer level reflected ILT burden in AAAs. Plasma D-dimer level and ILT volume were positively correlated with AAA size. Increasing value of plasma D-dimer and baseline ILT volume could be predictors of AAA progression.

CC chemokine receptor 2 functions in osteoblastic transformation of valvular interstitial cells.

AIMS: Calcific aortic valve disease (CAVD) emerges as a challenging clinical issue, which is associated with high cardiovascular mortality. It has been demonstrated that osteoblastic transformation of AVICs is a key mechanism of CAVD and C-C motif chemokine receptors (CCRs) may favor this process. Thus, we aimed to investigate whether CCRs were involved in osteoblastic transformation of AVICs during the development CAVD. MAIN METHODS: We first analyzed microarray data (GSE51472 and GSE12644) to identify differentially expressed genes between CAVD aortic valve tissue and normal samples, followed by verification of immunohistochemistry, qPCR and western blotting. Primary aortic valvular interstitial cells (AVICs) were incubated with specific inhibitors and/or siRNA of CCR2 and CCL2 under pro-calcifying medium. The levels of CCL2 in the medium were measured by ELISA. In addition, we used recombinant CCL2 to activate CCR2 in calcifying AVICs. Alizarin red S staining and calcium deposition were used to evaluate the degree of calcification. Western blotting was used to determine osteoblastic transformation of AVIC and total Akt and phosphorylated Akt expression. KEY FINDING: CCR2 levels were remarkably up-regulated in calcified aortic valve and calcifying AVICs. Silencing CCR2 inhibited the osteoblastic transformation and calcification of AVICs. In addition, recombinant CCL2 activated CCR2 and accelerated AVICs calcification through PI3K/Akt pathway. SIGNIFICANCE: We characterize abnormal activation of CCL2/CCR2 axis as a promoter of AVICs osteoblastic transformation and calcification. Our findings implicate the CCL2/CCR2-PI3K/Akt pathway as a potential target for treatment of CAVD.

Pharmacodynamic changes of platelet reactivity status in patients with chronic kidney disease after coronary artery stenting.

OBJECTIVES: This study was to evaluate platelet reactivity over time among patients with chronic kidney disease (CKD) receiving standard dose of clopidogrel after percutaneous coronary intervention (PCI). The effect of CYP2C19 loss-of-function genotypes on platelet reactivity was also determined. METHODS: Patients with CKD (n = 138) on maintenance dose of clopidogrel after PCI were enrolled. Platelet reactivity was assessed by measuring P2Y12 reaction units (PRU) with VerifyNow P2Y12 assay, and platelet reactivity index (PRI) with flow cytometric using vasodilator-stimulated phosphoprotein (VASP) at baseline and 2 weeks later, respectively. The genotypes of CYP2C19 were also measured concurrently. RESULTS: The proportion of patients with high platelet reactivity (HPR) ranged from 23.2% to 59.4%, and almost 1 in 5 patients had a dual conversion between HPR and non-HPR status. Patients carrying CYP2C19 loss-of-function genotypes showed a higher platelet reactivity than non-carriers, but with an undetermined HPR status between the first and second visits. The individual switch of HPR to non-HPR status existed in both loss-of-function genotype carriers and non-carriers. CONCLUSIONS: HPR conversions occur in a significant proportion of CKD patients with maintenance doses of clopidogrel treatment post-PCI, and this conversion was not confined to CYP2C19 loss-of-function genotype carriers. Risk stratification for treatment adjustment in personalized antiplatelet therapy should be investigated in future research.

Prognostic Impact of Fasting Plasma Glucose on Mortality and Re-Hospitalization in Patients with Acute Heart Failure.

BACKGROUND: The impact of fasting plasma glucose (FPG) on survival outcomes in patients with acute heart failure (HF) is unclear, and the relationship between intensity of glycemic control of FPG in diabetes mellitus (DM) patients and HF prognosis remains uncertain. This retrospective study aimed to evaluate the prognostic impact of FPG in patients with acute HF. METHODS: A total of 624 patients hospitalized with acute HF from October 2000 to April 2014 were enrolled in this study. All patients were stratified by three groups according to their admission FPG levels (i.e., DM, impaired fasting glucose [IFG], and non-DM). All-cause and cardiovascular mortality was the primary end point, and HF re-hospitalization was the secondary end point during follow-up period. RESULTS: A total of 587 patients were included in final analysis. The all-cause mortality rates of patients with DM, IFG, and non-DM were 55.5%, 40.3%, and 39.2%, with significant difference (P = 0.001). Moreover, compared with those with IFG (34.3%) and non-DM (32.6%), patients with DM had significantly higher rate of cardiovascular mortality (45.1%). Multiple Cox regression analysis showed that DM as well as IFG was related to all-cause mortality (DM: hazard ratio [HR] = 1.936, P < 0.001; IFG: HR = 1.672, P = 0.019) and cardiovascular mortality (DM: HR = 1.739, P < 0.001; IFG: HR = 1.817, P = 0.013). However, they were both unrelated to HF re-hospitalization. DM patients with strictly controlled blood glucose (FPG <3.9 mmol/L) had higher all-cause mortality than patients with non-DM, IFG, and DM patients with moderately controlled glucose (3.9 mmol/L≤ FPG <7.0 mmol/L). Likewise, both the primary end point and secondary end point were found to be worse in DM patients with poorly controlled blood glucose (FPG ≥7.0 mmol/L). CONCLUSIONS: IFG and DM were associated with higher all-cause mortality and cardiovascular mortality in patients with acute HF. The association between mortality and admission FPG in DM patients with acute HF appeared U-shaped.

Effect of Endoplasmic Reticulum Stress and Autophagy in the Regulation of Post-infarct Cardiac Repair.

BACKGROUND: Acute myocardial infarction (AMI) is reported to be accompanied by endoplasmic reticulum (ER) stress and autophagy induction. Nevertheless, the roles of ER stress and autophagy in post-infarct reparative fibrosis remain to be elucidated. AIM: To investigate the effects of ER stress and autophagy on the regulation of post-infarct reparative fibrosis. METHODS: The expression of GRP78 and LC3 in cardiac fibroblasts in human heart tissues obtained from patients with or without AMI was assessed by immunofluorescence. In vitro, human cardiac fibroblasts (HCFs) were stimulated by various agents, the expression of GRP78, LC3 and fibronectin in these was evaluated by immunoblot and/or immunofluorescence. RESULTS: After AMI, HCFs expressed significantly higher levels of GRP78 and LC3. ER stress inducer, tunicamycin (200 ng/mL) significantly increased the level of autophagy and reduced expression of fibronectin in HCFs, both of which were reversed by 4 Phenylbutyric acid. Under the condition of ER stress, the expression of fibronectin in HCFs was regulated by different levels of autophagy. LC3 co-localized with fibronectin when stimulated HCFs with tunicamycin. CONCLUSION: AMI induces ER stress in cardiac fibroblasts, down-regulating fibronectin via enhanced autophagy. These findings suggest that ER stress and autophagy may be a therapeutic target to improve prognosis of patients with AMI.

A Low-Normal Free Triiodothyronine Level Is Associated with Adverse Prognosis in Euthyroid Patients with Heart Failure Receiving Cardiac Resynchronization Therapy.

Thyroid dysfunction is prevalent in patients with heart failure (HF) and hypothyroidism is related to the adverse prognosis of HF subjects receiving cardiac resynchronization therapy (CRT). We aim to investigate whether low-normal free triiodothyronine (fT3) level is related to CRT response and the prognosis of euthyroid patients with HF after CRT implantation.One hundred and thirteen euthyroid patients who received CRT therapy without previous thyroid disease and any treatment affecting thyroid hormones were enrolled. All of patients were evaluated for cardiac function and thyroid hormones (serum levels of fT3, free thyroxine [fT4] and thyroid-stimulating hormone [TSH]). The end points were overall mortality and hospitalization for HF worsening. During a follow-up period of 39 ± 3 weeks, 36 patients (31.9%) died and 45 patients (39.8%) had hospitalization for HF exacerbation. A higher rate of NYHA III/IV class and a lower fT3 level were both observed in death group and HF event group. Multivariate Cox regression analyses disclosed that a lower-normal fT3 level (HR = 0.648, P = 0.009) and CRT response (HR = 0.441, P = 0.001) were both independent predictors of overall mortality. In addition, they were also both related to HF re-hospitalization event (P < 0.01 for both). Patients with fT3 < 3.00 pmol/L had a significantly higher overall mortality than those with fT3 ≥ 3.00 pmol/L (P = 0.027). Meanwhile, a higher HF hospitalization event rate was also found in patients with fT3 < 3.00 pmol/L (P < 0.001).A lower-normal fT3 level is correlated with a worse cardiac function an adverse prognosis in euthyroid patients with HF after CRT implantation.

Hydrogen Sulfide-Preconditioning of Human Endothelial Progenitor Cells Transplantation Improves Re-Endothelialization in Nude Mice with Carotid Artery Injury.

BACKGROUND/AIMS: The aim of present study was to test the hypothesis that preconditioning with sodium hydrosulfide (NaHS) could enhance the capacity of migration, adhesion and proliferation of endothelial progenitor cells (EPCs) in vitro, and also could improve the efficacy of EPCs transplantation for re-endothelialization in nude mice with carotid artery injury. The paper further addressed the underlying mechanisms. METHODS: EPCs were isolated from peripheral blood mononuclear cells of healthy male volunteers and the markers of EPCs were analyzed by flow cytometry. Thereafter, different concentrations of NaHS (25, 50, 100, 200 and 500 uM) were used for preconditioning EPCs. In vitro and in vivo migration, adhesion and proliferation as well as nitric oxide (NO) production of EPCs were evaluated. Carotid artery injury model was produced in nude mice and thereafter, NaHS-preconditioned EPCs were transplanted in order to evaluate their capacity of re-endothelialization. RESULTS: Cellular immuno-staining showed that isolated cells expressed the key markers of EPCs. In vitro, EPCs proliferation rates and NO production were gradually increased in a NaHS-concentration dependent manner, while these benefits were blocked at a concentration of 500 uM NaHS. Similarly, the migration and adhesion rates of EPCs were also increased the most prominently at a concentration of 200 µM NaHS. In vivo, compared to the control group, treatment with NaHS-preconditioned EPCs significantly enhanced the capacity of re-endothelialization of EPCs. Fluorescent microscope revealed that there were more EPCs homing to the injury vessels in the NaHS-preconditioned EPCs group than the non-preconditioned group. With the administration of AMPK or eNOS inhibitors respectively, the above benefits of NaHS-preconditioning were abrogated. CONCLUSION: These results suggested that NaHS-preconditioning enhanced the biological function and re-endothelialization of EPCs through the AMPK/eNOS signaling pathway.

Oxidized Low-Density Lipoprotein-Induced Cyclophilin A Secretion Requires ROCK-Dependent Diphosphorylation of Myosin Light Chain.

OBJECTIVE: Accumulation of cyclophilin A (CyPA) within atherosclerotic lesions is thought to be implicated in the progression of atherosclerosis. However, the source of CyPA within atherosclerotic lesions is still unknown. The aim of this study is to determine the role of oxidized low-density lipoproteins (ox-LDL) in vascular smooth muscle cell (VSMC)-derived CyPA secretion and the underlying mechanism. METHODS AND RESULTS: Abundant CyPA and α-smooth muscle actin (α-SMA) expressed in atherosclerotic lesions was observed in apolipoprotein E-deficient mice. ox-LDL induced CyPA secretion from a primary culture of rat aortic smooth muscle cells in a dose- and time-dependent manner. Sulfosuccinimidyloleate, a CD36 inhibitor, prevented the ox-LDL-induced CyPA secretion. Pre-exposure to either the actin-depolymerizing agent cytochalasin D or the actin-polymerizing agent jasplakinolide inhibited CyPA secretion induced by ox-LDL. Gene silencing of vesicle-associated membrane protein 2 suppressed ox-LDL-induced CyPA secretion. ox-LDL caused the phosphorylation of myosin light chain (MLC). Inhibition of MLC by blebbistatin reversed the secretion of CyPA and the phosphorylation of MLC induced by ox-LDL. MLC kinase inhibitor ML-7 reduced the monophosphorylation of MLC but did not reduce CyPA secretion. Pretreatment with the rho-associated coiled-coil kinase (ROCK) inhibitor Y27632 blocked diphosphorylation of MLC and secretion of CyPA induced by ox-LDL. CONCLUSIONS: ox-LDL-induced CyPA secretion requires vesicle transportation, actin remodeling and ROCK-dependent diphosphorylation of MLC. VSMC-derived CyPA induced by ox-LDL may be associated with increased CyPA expression in atherosclerotic lesions.

Effect of Metabolic Syndrome on Risk Stratification for Left Atrial or Left Atrial Appendage Thrombus Formation in Patients with Nonvalvular Atrial Fibrillation.

BACKGROUND: Metabolic syndrome (MS) is a risk factor for stroke and thromboembolism event. Left atrial or LA appendage (LA/LAA) thrombus is a surrogate of potential stroke. The relationship between MS and atrial thrombus remains unclear. In this study, we sought to investigate the effect of MS on risk stratification of LA/LAA thrombus formation in patients with nonvalvular atrial fibrillation (NVAF). METHODS: This cross-sectional study enrolled 294 consecutive NVAF patients without prior anticoagulant and lipid-lowering therapies. LA/LAA thrombus was determined by transesophageal echocardiography. Risk assessment of LA/LAA thrombus was performed using the CHADS2 , CHA2DS2 -VASc, MS, CHADS2 -MS, and CHA2DS2 -VASc-MS scores. Logistic regression analyses were performed to determine which factors were significantly related to LA/LAA thrombus. Odds ratio (OR) including 95% confidence interval was also calculated. The predictive powers of different scores for the risk of LA/LAA thrombus were represented by C-statistics and compared by receiver operating characteristic (ROC) analysis. RESULTS: LA/LAA thrombi were identified in 56 patients (19.0%). Logistic analysis showed that MS was the strongest risk factor for LA/LAA thrombus in NVAF patients (OR = 14.698, P < 0.001). ROC curve analyses revealed that the C-statistics of CHADS2 -MS and CHA2DS2 -VASc-MS was significantly higher than those of CHADS2 and CHA2DS2 -VASc scores (CHADS2 -MS vs. CHADS2 , 0.807 vs. 0.726, P = 0.0019). Furthermore, MS was helpful for identifying individuals with a high risk of LA/LAA thrombus in the population with a low risk of stroke (CHADS2 or CHA2DS2 -VASc score = 0). CONCLUSIONS: MS is associated with LA/LAA thrombus risk in patients with NVAF. In addition to the CHADS2 and CHA2DS2 -VASc scores, the CHADS2 -MS and CHA2DS2 -VASc-MS scores provide additional information on stroke risk assessment.

Overexpression of the ß2AR gene improves function and re-endothelialization capacity of EPCs after arterial injury in nude mice.

BACKGROUND: Proliferation and migration of endothelial progenitor cells (EPCs) play important roles in restoring vascular injuries. ß2 adrenergic receptors (ß2ARs) are widely expressed in many tissues and have a beneficial impact on EPCs regulating neoangiogenesis. The aim of the present study was to determine the effect of overexpressing ß2ARs in infused peripheral blood (PB)-derived EPCs on the re-endothelialization in injured vessels. METHODS: Induction of endothelial injury was performed in male nude mice that were subjected to wire-mediated injury to the carotid artery. Human PB-derived EPCs were transfected with an adenovirus serotype 5 vector expressing ß2AR (Ad5/ß2AR-EPCs) and were examined 48 h later. ß2AR gene expression in EPCs was detected by real-time polymerase chain reaction and Western blot analysis. In vitro, the proliferation, migration, adhesion, and nitric oxide production of Ad5/ß2AR-EPCs were measured. Meanwhile, phosphorylated Akt and endothelial nitric oxide synthase (eNOS), which are downstream of ß2AR signaling, were also elevated. In an in vivo study, CM-DiI-labeled EPCs were injected intravenously into mice subjected to carotid injury. After 3 days, cells recruited to the injury sites were detected by fluorescent microscopy, and the re-endothelialization was assessed by Evans blue dye. RESULTS: In vitro, ß2AR overexpression augmented EPC proliferation, migration, and nitric oxide production and enhanced EPC adhesion to endothelial cell monolayers. In vivo, when cell tracking was used, the number of recruited CM-DiI-labeled EPCs was significantly higher in the injured zone in mice transfused with Ad5/ß2AR-EPCs compared with non-transfected EPCs. The degree of re-endothelialization was also higher in the mice transfused with Ad5/ß2AR-EPCs compared with non-transfected EPCs. We also found that the phosphorylation of Akt and eNOS was increased in Ad5/ß2AR-EPCs. Preincubation with ß2AR inhibitor (ICI118,551), Akt inhibitor (ly294002), or eNOS inhibitor (L-NAME) significantly attenuated the enhanced in vitro function and in vivo re-endothelialization capacity of EPCs induced by ß2AR overexpression. CONCLUSIONS: The present study demonstrates that ß2AR overexpression enhances EPC functions in vitro and enhances the vascular repair abilities of EPCs in vivo via the ß2AR/Akt/eNOS pathway. Upregulation of ß2AR gene expression through gene transfer may be a novel therapeutic target for endothelial repair.

Role of Circulating Fibrocytes in Cardiac Fibrosis.

OBJECTIVE: It is revealed that circulating fibrocytes are elevated in patients/animals with cardiac fibrosis, and this review aims to provide an introduction to circulating fibrocytes and their role in cardiac fibrosis. DATA SOURCES: This review is based on the data from 1994 to present obtained from PubMed. The search terms were "circulating fibrocytes " and "cardiac fibrosis ". STUDY SELECTION: Articles and critical reviews, which are related to circulating fibrocytes and cardiac fibrosis, were selected. RESULTS: Circulating fibrocytes, which are derived from hematopoietic stem cells, represent a subset of peripheral blood mononuclear cells exhibiting mixed morphological and molecular characteristics of hematopoietic and mesenchymal cells (CD34+/CD45+/collagen I+). They can produce extracellular matrix and many cytokines. It is shown that circulating fibrocytes participate in many fibrotic diseases, including cardiac fibrosis. Evidence accumulated in recent years shows that aging individuals and patients with hypertension, heart failure, coronary heart disease, and atrial fibrillation have more circulating fibrocytes in peripheral blood and/or heart tissue, and this elevation of circulating fibrocytes is correlated with the degree of fibrosis in the hearts. CONCLUSIONS: Circulating fibrocytes are effector cells in cardiac fibrosis.