Relationship between epicardial adipose tissue measured by computed tomography and premature ventricular complexes originating from different sites.

AIMS: This study aims to explore the association between the features of epicardial adipose tissue (EAT) in different zones and premature ventricular complexes (PVCs) originating from different sites by computed tomography (CT). METHODS AND RESULTS: A total of 136 patients who underwent radiofrequency ablation for PVCs were incorporated in this study. One hundred and thirty-six matched controls were included in this study using the case-control method (1:1 matching). PVCs were classified into four subgroups: (1) right ventricular outflow tract (RVOT-PVCs), (2) non-RVOT of the right ventricle (RV-PVCs), (3) left ventricular outflow tract (LVOT-PVCs), and (4) non-LVOT of the left ventricle (LV-PVCs). The volume and density of EAT were quantified by CT. Patients with PVCs had a significantly higher volume and lower density of EAT than the controls (P < 0.001). The LVOT-PVCs and LV-PVCs had a higher left ventricle periventricular EAT volume (LV-EATv) proportion (P < 0.05). The right ventricle periventricular EAT volume (RV-EATv) proportion was higher in ROVT-PVCs and LVOT-PVCs (P < 0.05). RVOT-PVC patients had a higher volume ratio and a smaller density differential (P < 0.05). Patients with LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential (P < 0.05). CONCLUSION: Higher volume and lower density of EAT were significantly associated with frequent PVCs. The RVOT-PVC patients had a higher volume ratio and a smaller density differential. The LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential. These suggest a link between EAT structural properties and PVCs and a potential role for regional EAT in the development of PVCs.

Effects of Chronic Remote Ischemic Conditioning on Atrial Fibrillation Burden in Patients with Permanent Pacemakers.

This study aimed to evaluate the effects of chronic remote ischemic conditioning (CRIC) on atrial fibrillation burden in patients with an implanted pacemaker. Sixty-six patients with permanent pacemakers were randomly divided into the CRIC group and control group after 4 weeks of screening. CRIC treatment was performed twice daily for 12 weeks. The remote ischemic conditioning protocol consisted of 4 × 5 minutes inflation/deflation of the blood pressure cuff applied in the upper arm to create intermittent arm ischemia. Sixty-one patients (31 patients in the CRIC group and 30 patients in the control group) completed the study. CRIC was well tolerated by patients after 12 weeks of treatment. The burden of atrial fibrillation (AF) in the CRIC group decreased significantly at 4 weeks compared with that at 0 weeks (14.7% ± 18.5% versus 17.0% ± 20.7%, P < 0.001), which further decreased at 12 weeks compared with that at 0 weeks (8.6% ± 10.2% versus 17.0% ± 20.7%, P < 0.001) and that at 4 weeks (8.6% ± 10.2% versus 14.7% ± 18.5%, P < 0.001), which was not observed in the control group. AF burden also reduced significantly after 12-week CRIC compared with that in the control group (8.6% ± 10.2% versus 17.6% ± 19.5%, P = 0.013). Repeated measurement ANOVA showed that the changes in AF burden were associated with CRIC instead of time (P < 0.01). In addition, there were trends that the longest duration of AF and cumulative numbers of atrial high-rate episodes (AHREs) reduced after 12-week CRIC. This study suggests that a 12-week course of CRIC treatment could reduce AF burden in patients with permanent pacemakers, supporting the widespread use of CRIC in the daily lives of these patients, which needs to be verified in the future.

Treatment of femoropopliteal lesions with the AngioSculpt scoring balloon - results from the Heidelberg PANTHER registry.

BACKGROUND: Treatment of calcified femoropopliteal lesions remains challenging, even in the era of drug-eluting balloon angioplasty. Lesion recoil and dissections after standard balloon angioplasty in calcific lesions often require subsequent stent implantation. Additionally, poor patency rates in calcified lesions despite the use of drug-eluting balloons may be due to the limited penetration depth of the antiproliferative drug in the presence of vascular calcium deposits. Therefore, preparation of calcified lesions with the AngioSculpt™ scoring balloon might be a valuable option either as a stand-alone treatment, followed by drug-eluting balloon angioplasty or prior to subsequent stent deployment. PATIENTS AND METHODS: In this retrospective, single centre registry, 124 calcified femoropopliteal lesions were treated in 101 subsequent patients. All patients were treated with scoring balloon angioplasty, either alone, in combination with drug-eluting balloons, or prior to stent deployment. The primary outcome was safety and technical success during the index procedure as well as patency at six and 12 months, as evaluated by duplex sonography. RESULTS: Successful scoring was safely performed in all 124 lesions with the AngioSculpt™ balloon. Overall primary patency after 12 months was 81.2 %. Patency rates did not differ significantly between the three treatment strategies. Degree of calcification did not predict patency. Improved clinical outcomes (Rutherford-Becker class and ankle-brachial index) were also observed in the study cohort. CONCLUSIONS: Preparation with the AngioSculpt™ scoring balloon offers a safe and valuable treatment option for calcified femoropopliteal lesions.

Effects of Remote Ischaemic Conditioning on Heart Rate Variability and Cardiac Function in Patients With Mild Ischaemic Heart Failure.

BACKGROUND: Cardioprotective effects of remote ischaemic conditioning (RIC) in the setting of ischaemic heart disease have been shown recently. But the effects of RIC on heart rate variability (HRV) and cardiac function in patients with stable ischaemic heart failure (IHF) are still unknown. METHODS: Fifty patients with stable IHF were enrolled and randomly divided into RIC group and control group. Remote ischaemic conditioning treatment was performed twice a day for 6 weeks. A remote is chaemic conditioning protocol consisted of 4×5min inflation/deflation of the blood pressure cuff applied in the upper arm to create intermittent arm ischaemia. B-type natriuretic peptide (BNP), left ventricular ejection fraction (LVEF), 24-hour ambulatory electrocardiogram, and 6-minute walk distance (6MWD) were all assessed in two groups. RESULTS: Forty-seven patients completed the study. Remote ischaemic conditioning was well-tolerated by patients in the RIC group after 6 weeks treatment and LVEF showed a significant increase, from 39.2% to 43.4% (p<0.001), as well as decreased BNP, increased 6MWD and HRV, but this was not observed in the control group. In addition, the patients treated with RIC also showed improved NYHA class, LVEF, 6MWD, BNP level and HRV compared to control group. CONCLUSIONS: This study suggests that a 6-week course of RIC treatment could improve cardiac function and HRV in patients with mild and stable IHF, supporting widespread use of RIC in the daily lives of these patients.

Effects of the factor Xa inhibitor, fondaparinux, on the stability of atherosclerotic lesions in apolipoprotein E-deficient mice.

BACKGROUND: Atherosclerosis is a progressive inflammatory disease that can lead to sudden cardiac events by plaque rupture and subsequent thrombosis. Factor Xa (FXa) not only occupies a crucial position in the coagulation cascade responsible for thrombin generation, but also has pro-inflammatory effects. The hypothesis that Fondaparinux, the selective FXa inhibitor, attenuates plaque progression and promotes stability of atherosclerotic lesions was assessed. METHODS AND RESULTS: Fondaparinux (5 mg/kg body weight/day) or 0.9% saline was intraperitoneally administered for 4 weeks to apolipoprotein E-deficient mice (n=12 per group) with established atherosclerotic lesions in the innominate arteries. Fondaparinux did not remarkably decrease the progression of atherosclerosis development in apolipoprotein E-deficient mice, but increased the thickness of fibrous cap (P=0.049) and decreased the ratio of necrotic core (P=0.001) significantly. Moreover, Fondaparinux reduced the staining against Mac-2 (P=0.017), α-SMA (P=0.002), protease-activated receptor (PAR)-1 (P=0.001), PAR-2 (P=0.003), CD-31 (P=0.024), MMP-9 (P=0.000), MMP-13(P=0.011), VCAM-1 (P=0.041) and the mRNA expression of inflammatory mediators (P<0.05) significantly, such as interleukin (IL)-6, MCP-1, IFN-γ, TNF-α, IL-10 and Egr-1. CONCLUSIONS: Fondaparinux, the selective FXa inhibitor, can promote the stability of atherosclerotic lesions in apolipoprotein E-deficient mice, possibly through inhibiting expression of the inflammatory mediators in plaque and reduced synthesis of MMP-9 and MMP-13.

Cytoprotective signaling by activated protein C requires protease-activated receptor-3 in podocytes.

The cytoprotective effects of activated protein C (aPC) are well established. In contrast, the receptors and signaling mechanism through which aPC conveys cytoprotection in various cell types remain incompletely defined. Thus, within the renal glomeruli, aPC preserves endothelial cells via a protease-activated receptor-1 (PAR-1) and endothelial protein C receptor-dependent mechanism. Conversely, the signaling mechanism through which aPC protects podocytes remains unknown. While exploring the latter, we identified a novel aPC/PAR-dependent cytoprotective signaling mechanism. In podocytes, aPC inhibits apoptosis through proteolytic activation of PAR-3 independent of endothelial protein C receptor. PAR-3 is not signaling competent itself as it requires aPC-induced heterodimerization with PAR-2 (human podocytes) or PAR-1 (mouse podocytes). This cytoprotective signaling mechanism depends on caveolin-1 dephosphorylation. In vivo aPC protects against lipopolysaccharide-induced podocyte injury and proteinuria. Genetic deletion of PAR-3 impairs the nephroprotective effect of aPC, demonstrating the crucial role of PAR-3 for aPC-dependent podocyte protection. This novel, aPC-mediated interaction of PARs demonstrates the plasticity and cell-specificity of cytoprotective aPC signaling. The evidence of specific, dynamic signaling complexes underlying aPC-mediated cytoprotection may allow the design of cell type specific targeted therapies.

Crocin inhibits KBTBD7 to prevent excessive inflammation and cardiac dysfunction following myocardial infarction.

Myocardial infarction (MI) refers to myocardial ischemic necrosis that is caused by coronary artery disease. Notably, crocin has protective effects on the heart. The present study aimed to i) investigate the protective effect of crocin, an active ingredient in Gardenia jasminoides Ellis and Crocus sativus L., on myocardial ischemia and ii) to verify the interaction between crocin and kelch repeat and BTB domain­containing protein 7 (KBTBD7), which is a novel member of the BTB­kelch protein family. In the present study, the left anterior descending coronary artery was ligated to establish a myocardial ischemia­reperfusion injury (MIRI) model in rats and the protective effect of crocin on rat myocardial tissue was observed. The levels of the inflammatory cytokines, interleukin (IL)­1ß, IL­6 and tumor necrosis factor α (TNFα), in the sham, MI model, MI + crocin (100 mg/kg) and MI + crocin (200 mg/kg) groups were compared in the rat myocardial tissue. The TUNEL assay was used to detect apoptosis of myocardial cells. In addition, RAW264.7 cells were stimulated with the inflammatory factors recombinant mouse high mobility group box 1 (rmHMGB1) and recombinant mouse heat shock protein 60 (rmHSP60). The inhibitory effect of crocin on inflammatory cytokine levels was observed using ELISA. Western blotting was used to detect the inhibitory effect of crocin on KBTBD7. The inhibitory effect of KBTBD7 knockdown on MAPK and nuclear factor (NF)­κB signaling pathways was also analyzed. The expression levels of IL­1ß, IL­6 and TNFα were significantly decreased in the crocin­treated groups compared with in the model group. Crocin significantly reduced the apoptosis of myocardial cells and significantly inhibited the release of inflammatory cytokines induced by rmHMGB1 and rmHSP60. KBTBD7 was determined to be a target of crocin. Knockdown of KBTBD7 significantly inhibited p38 and NF­κB signaling pathways. Furthermore, the results demonstrated that KBTBD7 knockdown significantly reduced the production of inflammatory cytokines induced by rmHMGB1 and rmHSP60. KBTBD7 knockdown also significantly reduced p38 and NF­κB signaling in the rmHMGB1­ and rmHSP60­treated groups. The present study demonstrated the potential protective effect of crocin on MIRI in rats. The underlying mechanism may be through direct inhibition of KBTBD7, thereby inhibiting excessive inflammatory responses and myocardial cell apoptosis following myocardial infarction.

Self-reported sleep pattern and recurrence of atrial fibrillation after catheter ablation.

BACKGROUND: Increasing evidence has shown the relationship between sleep and the recurrence of atrial fibrillation (AF). However, the association of different sleep patterns with AF recurrence after catheter ablation was rarely studied. We aimed to assess the role of different sleep behaviors in the risk of AF recurrence after catheter ablation. METHODS AND RESULTS: A total of 416 consecutive participants from Zhongda hospital of Southeast University were finally analyzed. Sleep patterns were defined by chronotype, sleep duration, insomnia, snoring, and daytime sleepiness. A total of 208 patients (50.0%) had a healthy sleep pattern within a mean follow-up of 32.42 ± 18.18 months. The observed number of patients with AF recurrence was 10 (50.0%), 80 (42.6%), and 40 (19.2%) in unhealthy, intermediate and healthy sleep groups, respectively (p < .01). After adjusting covariates, unhealthy sleep pattern was significantly associated with AF recurrence [hazard ratio = 3.47 (95% confidence interval CI: 1.726-6.979, p < .001)]. Sleep disorders such as inadequate sleep time (time <7 h or >8 h), insomnia and excessive sleepiness during daytime were associated with a higher risk of recurrence. Otherwise, improvement in sleep seemed to be associated with decreased risk of AF recurrence. CONCLUSION: This retrospective study indicates that adherence to a healthy sleep pattern is associated with a lower risk of AF recurrence. Also, improved sleep before ablation is associated with a lower risk of AF recurrence.

Circ-GTF2I/miR-590-5p Axis Aggravates Myocardial Ischemia-Reperfusion Injury by Regulating Kelch Repeat and BTB Domain-Containing Protein 7.

Purpose: We investigated the effect of the circular RNA (circRNA) general transcription factor IIi (GTF2I) on myocardial ischemia (MI) deterioration and neonatal rat cardiomyocyte damage. Methods: The cell experiment was performed by using neonatal rat cardiomyocytes. Moreover, a hypoxia/reoxygenation treatment model was established. Cell Counting Kit-8 assay was conducted, and EdU cell proliferation was detected. Cell apoptosis was detected via flow cytometry and quantitative RT-PCR (RT-qPCR). Binding detection was performed through a double-luciferase reporter assay. Interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and lactate dehydrogenase (LDH) were detected via enzyme-linked immunosorbent assay (ELISA). Results: Compared with that in the sham and control groups, circ-GTF2I expression in MIRI and the hypoxia/reoxygenation treatment model was significantly upregulated in vivo and in vitro. The knockdown of circ-GTF2I relieved neonatal rat cardiomyocyte damage and MI. Further detection through the double-luciferase reporter assay confirmed that the binding site of circ-GTF2I to miR-590-5p and miR-590-5p was Kelch repeat and BTB domain-containing protein 7 (KBTBD7). ELISA and RT-qPCR results showed that circ-GTF2I induced the abnormal expressions of IL-6 TNF-α, LDH, Bax, Bcl-2, and Cyt-c in MIRI and the hypoxia/reoxygenation treatment models by regulating miR-590-5p and the heart development transcription factor KBTBD7. Conclusions: CircRNA circ-GTF2I aggravated MIRI and neonatal rat cardiomyocyte damage in vivo and in vitro by regulating miR-590-5p and the heart development transcription factor KBTBD7.

WiSE CRT Is Beneficial for Heart Failure Patients as a Rescue Therapy: Evidence From a Meta-Analysis.

Background: Leadless endocardial left ventricular (LV) pacing resynchronization therapy is a novel solution for patients with heart failure (HF) in whom conventional cardiac resynchronization therapy (CRT) failed. Methods: PubMed and the Cochrane Library were searched for relevant cohort studies. Clinical outcomes of interest such as ejection fraction (EF), QRS duration (QRSd), and left ventricular end-systolic volume (LVESV) were extracted and analyzed. Results: Five studies involving 175 HF patients for WiSE CRT were included, and patients were followed-up for 6 months. The implanted success rate ranged from 76.5 to 100%. WiSE CRT resulted in significantly narrower QRSd [mean difference (MD): -38.21 ms, 95% confidence interval (CI): -44.36 to -32.07, p < 0.001], improved left ventricular ejection fraction (MD: 6.07%, 95% CI: 4.43 to 7.71, I2 = 0%, p < 0.001), reduced left ventricular end-systolic volume (MD: -23.47 ml, 95% CI: -37.18 to -9.13, p < 0.001), and reduced left ventricular end-diastolic volume (MD: -24.02 ml, 95% CI: -37.01 to -11.03, p = 0.02). Conclusion: Evidence from current studies suggests that leadless endocardial LV pacing resynchronization is effective for HF patients who failed conventional CRT or needed a device upgrade, and it may be an interesting rescue therapy.

Nicotinic acid has anti-atherogenic and anti-inflammatory properties on advanced atherosclerotic lesions independent of its lipid-modifying capabilities.

Inflammation contributes to atherosclerotic plaque initiation and progression. Recent studies suggest that nicotinic acid has anti-inflammatory effects independent of its lipid-modifying capabilities. We assessed the hypothesis that administration of nicotinic acid to older apolipoprotein E (apoE)-deficient mice with established lesions will reduce lesion size and plaque inflammation independent of its lipid-modifying effects. Therefore nicotinic acid was administered to 27-week-old apo E-deficient mice exhibiting advanced atherosclerotic lesions within the innominate artery. After 27 weeks of treatment both animal groups had no significant changes in plasma lipid levels. Mice treated with nicotinic acid (n = 22) demonstrated a 30% reduction in total lesion area compared with controls (n = 20). Furthermore, they revealed a more stable plaque composition with an increase in fibrous cap thickness and a reduction in the size of the necrotic core. Immunohistochemistry demonstrated a reduced accumulation of macrophages and a reduced expression of vascular cell adhesion molecule-1 and tissue factor. Additionally, administration of nicotinic acid significantly reduced tumor necrosis factor alpha expression in the thoracic aorta as demonstrated by real-time PCR. In conclusion, these data suggest that long-term administration of nicotinic acid has anti-atherogenic and anti-inflammatory properties on advanced atherosclerotic lesions, which are independent of its lipid-modifying actions.

Evaluation of plaque stability of advanced atherosclerotic lesions in apo E-deficient mice after treatment with the oral factor Xa inhibitor rivaroxaban.

AIM: Thrombin not only plays a central role in thrombus formation and platelet activation, but also in induction of inflammatory processes. Activated factor X (FXa) is traditionally known as an important player in the coagulation cascade responsible for thrombin generation. We assessed the hypothesis that rivaroxaban, a direct FXa inhibitor, attenuates plaque progression and promotes stability of advanced atherosclerotic lesions in an in vivo model. METHODS AND RESULTS: Rivaroxaban (1 or 5 mg/kg body weight/day) or standard chow diet was administered for 26 weeks to apolipoprotein E-deficient mice (n = 20 per group) with already established atherosclerotic lesions. There was a nonsignificant reduction of lesion progression in the high-concentration group, compared to control mice. FXa inhibition with 5 mg Rivaroxaban/kg/day resulted in increased thickness of the protective fibrous caps (12.3 ± 3.8 µm versus 10.1 ± 2.7 µm; P < .05), as well as in fewer medial erosions and fewer lateral xanthomas, indicating plaque stabilizing properties. Real time-PCR from thoracic aortas revealed that rivaroxaban (5 mg/kg/day) treatment reduced mRNA expression of inflammatory mediators, such of IL-6, TNF-α, MCP-1, and Egr-1 (P < .05). CONCLUSIONS: Chronic administration of rivaroxaban does not affect lesion progression but downregulates expression of inflammatory mediators and promotes lesion stability in apolipoprotein E-deficient mice.

Risk factors of left atrial appendage thrombus in patients with non-valvular atrial fibrillation.

OBJECTIVE: To investigate the risk factors of left atrial appendage thrombus (LAAT) in patients with non-valvular atrial fibrillation (AF). METHODS: We collected the clinical data of patients with non-valvular AF who underwent transesophageal echocardiography (TEE) at the Zhongda Hospital of Southeast University between January 2016 and June 2019. The patients were divided into two groups, LAAT and non-LAAT. We performed comparative analysis, receiver operating characteristic (ROC) curve analysis and logistic regression analysis to estimate the risk factors of LAAT. RESULTS: A total of 442 patients with non-valvular AF were enrolled in the study. LAAT was detected by TEE in 20 cases (4.7%). Compared with patients without LAAT, patients with LAAT had higher CHA2DS2-VASc scores (3 vs 2, p = 0.001), higher values of D-dimer (180.0 vs 90.0 µg/L, p = 0.003), larger LA anteroposterior diameters (50.5 vs 41.0 mm, p < 0.001) and higher ratios of non-paroxysmal AF (85.0% vs 23.6%, p < 0.001). ROC curve analysis revealed that the cutoff value of LA anteroposterior diameter was 49.5 mm. After adjusting for other confounders, logistic regression analysis showed that enlarged LA (anteroposterior diameter ≥49.5 mm) and non-paroxysmal AF were independently associated with higher risks of LAAT (OR = 7.28, 95% CI: 2.36-22.47; OR = 8.89, 95% CI: 2.33-33.99, respectively). The proportions of LAAT in patients with larger LA (anteroposterior diameter ≥49.5 mm), non-paroxysmal AF and both larger LA and non-paroxysmal AF were 30% (12/40), 15.2% (17/112) and 39.1% (9/23), respectively. CONCLUSION: Enlarged LA (anteroposterior diameter ≥49.5 mm) and non-paroxysmal AF were independent risk factors of LAAT in non-valvular AF patients.

Rhizoma Coptidis inhibits LPS-induced MCP-1/CCL2 production in murine macrophages via an AP-1 and NFkappaB-dependent pathway.

INTRODUCTION: The Chinese extract Rhizoma coptidis is well known for its anti-inflammatory, antioxidative, antiviral, and antimicrobial activity. The exact mechanisms of action are not fully understood. METHODS: We examined the effect of the extract and its main compound, berberine, on LPS-induced inflammatory activity in a murine macrophage cell line. RAW 264.7 cells were stimulated with LPS and incubated with either Rhizoma coptidis extract or berberine. Activation of AP-1 and NFkappaB was analyzed in nuclear extracts, secretion of MCP-1/CCL2 was measured in supernatants. RESULTS: Incubation with Rhizoma coptidis and berberine strongly inhibited LPS-induced monocyte chemoattractant protein (MCP)-1 production in RAW cells. Activation of the transcription factors AP-1 and NFkappaB was inhibited by Rhizoma coptidis in a dose- and time-dependent fashion. CONCLUSIONS: Rhizoma coptidis extract inhibits LPS-induced MCP-1/CCL2 production in vitro via an AP-1 and NFkappaB-dependent pathway. Anti-inflammatory action of the extract is mediated mainly by its alkaloid compound berberine.

Protease-Activated Receptor-2 Deficiency Attenuates Atherosclerotic Lesion Progression and Instability in Apolipoprotein E-Deficient Mice.

Inflammatory mechanisms are involved in the process of atherosclerotic plaque formation and rupture. Accumulating evidence suggests that protease-activated receptor (PAR)-2 contributes to the pathophysiology of chronic inflammation on the vasculature. To directly examine the role of PAR-2 in atherosclerosis, we generated apolipoprotein E/PAR-2 double-deficient mice. Mice were fed with high-fat diet for 12 weeks starting at ages of 6 weeks. PAR-2 deficiency attenuated atherosclerotic lesion progression with reduced total lesion area, reduced percentage of stenosis and reduced total necrotic core area. PAR-2 deficiency increased fibrous cap thickness and collagen content of plaque. Moreover, PAR-2 deficiency decreased smooth muscle cell content, macrophage accumulation, matrix metallopeptidase-9 expression and neovascularization in plaque. Relative quantitative PCR assay using thoracic aorta revealed that PAR-2 deficiency reduced mRNA expression of inflammatory molecules, such as vascular cell adhesion molecule-1, intercellular adhesion molecule-1, tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1. In vitro experiment, we found that PAR-2 deficiency reduced mRNA expression of interferon-γ, interleukin-6, TNF-α and MCP-1 in macrophage under unstimulated and lipopolysaccharide-stimulated conditions. These results suggest that PAR-2 deficiency attenuates the progression and instability of atherosclerotic plaque.

Factor Xa induces pro-inflammatory cytokine expression in RAW 264.7 macrophages via protease-activated receptor-2 activation.

Coagulation proteases have been suggested to trigger a diversity of inflammatory responses in addition to their critical role in the coagulation cascade. It has been well established that the inflammatory and coagulation pathways are invariably linked. However, the mechanisms through which coagulation protease factor Xa (FXa) causes inflammation remain unclear. Thus, we assessed the pro-inflammatory effects of FXa in RAW 264.7 macrophages. We show that FXa elicits signal transduction in RAW 264.7 macrophages. FXa-induced signal transduction was dependent on the activation of protease-activated receptor 2 (PAR-2), PAR-2 desensitization but not PAR-1 desensitization abolished FXa-induced ERK1/2 phosphorylation. The PAR-2-dependent cellular effects of FXa led to the expression of pro-inflammatory cytokines IL-6, IL-8, TNF-α and IFN-γ in RAW 264.7 macrophages. Furthermore, a specific inhibitor of the ERK1/2 pathway, U0126, decreased the FXa-induced pro-inflammatory cytokines expression significantly. Taken together, our data indicate that FXa induces PAR-2-dependent pro-inflammatory activity in RAW 264.7 macrophages through the ERK1/2 pathway.

Minocycline reduces plaque size in diet induced atherosclerosis via p27(Kip1).

OBJECTIVE: Minocycline, a tetracycline derivate, mediates vasculoprotective effects independent of its antimicrobial properties. Thus, minocycline protects against diabetic nephropathy and reduces neointima formation following vascular injury through inhibition of apoptosis or migration, respectively. Whether minocycline has an effect on primary atherogenesis remains unknown. METHODS: Using morphological and immunohistochemical analyses we determined de novo atherogenesis in ApoE-/- mice receiving a high fat diet (HFD) with or without minocycline treatment. The effect of minocycline on proliferation, expression of p27(Kip1) or PARP-1 (Poly [ADP-ribose] polymerase 1), or on PAR (poly ADP-ribosylation) modification in vascular smooth muscle cells (VSMC) was analyzed in ex vivo and in vitro (primary human and mouse VSMC). RESULTS AND CONCLUSION: Minocycline reduced plaque size and stenosis in ApoE-/- HFD mice. This was associated with a lower number and less proliferation of VSMC, reduced PAR (poly ADP-ribosylation) modification and increased p27(Kip1) expression within the plaques. In agreement with the ex vivo data minocycline reduced proliferation, PARP-1 expression, PAR modification while inducing p27 expression in human and mouse VSMC in vitro. These effects were observed at a low minocycline concentration (10 µM), which had no effect on VSMC migration or apoptosis. Minocycline inhibited PARP-1 and induced p27(Kip1) expression in VSMC as efficiently as the specific PARP-1 inhibitor PJ 34. Knock down of p27(Kip1) abolished the antiproliferative effect of minocycline. These data establish a novel antiatherosclerotic mechanism of minocycline during de novo atherogenesis, which depends on p27(Kip1) mediated inhibition of VSMC proliferation.