Polycyclic aromatic hydrocarbons induce endothelial injury through miR-155 to promote atherosclerosis.

Polycyclic aromatic hydrocarbons (PAHs) are considered as an external factor that induces atherosclerotic cardiovascular disease. Although miR-155 is known to be involved in cardiovascular disease, whether it is involved in PAH-induced arteriosclerosis remains unclear. We evaluated the effects of PAHs on vascularization, permeability, and miR-155 expression in HUVECs. We found that PAHs-induced sclerosis of HUVECs was characterized by increasing permeability, decreasing proliferation, and vascular lumen number. The expression of miR-155 was upregulated by PAHs treatment, and transfection with miR-155 inhibitor could reverse above effect of PAHs-induced sclerosis. Meanwhile, transcriptome sequencing revealed that 63 genes were downregulated in the group of PAHs treatment alone, and were then upregulated in the miR-155 inhibitor group. These genes were mainly involved in complement and coagulation cascades, cytokine-cytokine receptor interaction, TNF signaling pathway, and NF-kappa B signaling pathway. Among these 63 genes, SERPIND1 was directly targeted and regulated by miR-155. Further in vivo experiments in ApoE-/- mice confirmed that PAH accelerates the development of arteriosclerosis by promoting the expression of miR-155 to downregulate the SERPIND1. Therefore, PAH exaggerates atherosclerosis by activating miR-155-dependent endothelial injury. This study provides a fundamental insight on the miR-155 mechanism for PAHs enhancing atherosclerosis and miR-155 potentially serving as a novel drug target.

Impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate.

OBJECTIVE: To investigate the impact of meteorological conditions and PM2.5 on the onset of acute aortic dissection in monsoonal climate. METHODS: A linear regression analysis was performed in monsoonal climate epidemiological survey for a period of four years on the impact of meteorological factors (minimal temperature, mean temperature, maximal temperature, average daily surface temperature, day temperature range, relative humidity, mean wind speed, and atmospheric pressure) and PM2.5 concentration on the daily incidences of acute aortic dissections. Meteorological variables and PM2.5 concentration were retrieved on a daily basis from Beijing Regional Climate Center and the Ministry of Environmental Protection of the People's Republic of China's website, and the daily incidences of acute aortic dissections were retrieved from the Clinical Data Analysis and Reporting System in the Emergency and Critical Care Center of Beijing Anzhen Hospital. RESULTS: During the study period (from January 2011 to December 2014), 1164 patients were identified as having acute aortic dissections. The corresponding incidences in spring and autumn were 0.96 and 1.00, respectively, which significantly higher than that in summer and winter. The incidences of acute aortic dissection in a day could be predicted by diurnal temperature range (DTR) using the following linear multiple regression models: incidences of acute aortic dissection = 0.543 + 0.025 × DTR. CONCLUSION: This is the first study to show an attributable effect of DTR on acute aortic events in monsoonal climate. Our study confirms that meteorological variables were important factors influencing the incidence of acute aortic dissection.

Serum uric acid levels correlate with recurrence of paroxysmal atrial fibrillation after catheter ablation.

BACKGROUND: Recently there has been a great deal of interest in the role of serum uric acid (SUA) in atrial fibrillation (AF). The objective of this study was to establish whether there is a relationship between levels of SUA and recurrence of paroxysmal AF after catheter ablation. METHODS: Three hundred and thirty patients diagnosed with paroxysmal AF were analyzed. Patients were categorized into quartiles on the basis of their pre-operative SUA measurement and follow-up, and Kaplan-Meier estimation with a Log-rank test was used for the analysis of the influence of SUA on the recurrence of AF. Pre-procedural clinical variables were correlated with the clinical outcome after ablation using multivariate Logistic analysis. A Cox proportional hazards model was used to estimate the relationship between SUA and the recurrence of AF. RESULTS: After a mean follow-up of (9.341 ± 3.667) (range 3.0 - 16.3) months, recurrence rates from the lowest SUA quartile to the highest SUA quartile were 16.0%, 26.4%, 28.3%, and 29.3% respectively (P = 0.014). After adjustment for gender, body mass index (BMI), hypertension, serum levels of high sensitivity C-reactive protein (hsCRP), triglyceride (TG), left atrial diameter (LA), estimated glomerular filtration rate (eGFR), and SUA, there was an increased risk of recurrence in subjects in the highest SUA quartile compared with those in the lowest quartile (hazard ratio 2.804, 95% confidence interval 1.466 - 5.362, P = 0.002). Following multivariate Logistical analysis, SUA was found to be an independent predictor of recurrence (hazard ratio 1.613, 95% confidence interval 1.601 - 1.625, P = 0.014). CONCLUSION: In a retrospective study of patients with paroxysmal AF undergoing catheter ablation, elevated preoperative SUA levels were associated with a higher rate of recurrence of AF.