Proteomic biomarkers for noninvasive left atrial appendage thrombus prediction in patients with atrial fibrillation.

INTRODUCTION: The CHA2DS2-VASc score, used to assess the risk of left atrial appendage thrombus (LAAT) formation in patients with atrial fibrillation (AF), has limited predictive value. Moreover, transesophageal echocardiography imaging, the gold standard diagnostic method to identify thrombi, is semi-invasive. Consequently, there is a need for alternative and noninvasive diagnostic methods for LAAT risk assessment. METHODS: Deep proteomic analysis was conducted in plasma samples from 8 patients with nonvalvular AF, divided into thrombus and control groups (4 patients in each group) based on the presence or absence of LAAT. Biomarkers associated with LAAT were validated using an enzyme-linked immunosorbent assay in a cohort of 179 patients with available clinical, transthoracic, and transesophageal echocardiography data. Predictive models were developed to assess the improvement in LAAT identification. RESULTS: The LAAT group had higher CHA2DS2-VASc scores, larger LA diameter, and lower LAA flow velocities. Deep proteomic analysis identified 30 differentially expressed proteins, including myosin light chain 4, prenylcysteine oxidase 1 (PCYOX1), and decorin as potential diagnostic biomarkers of LAAT. The model showed that PCYOX1 and decorin provided an area under the curve (AUC) of 0.970 for LAAT prediction compared with 0.672 in a model including the CHA2DS2-VASc score and LAA cauliflower morphology. The incremental value of proteomic biomarkers for LAAT in patients with nonvalvular AF was further confirmed with the net reclassification improvement and integrated discrimination improvement indices. CONCLUSIONS: Protein levels of PCYOX1 and decorin improve the predictive performance for LAAT in patients with nonvalvular AF.

Identification of key genes increasing susceptibility to atrial fibrillation in nonalcoholic fatty liver disease and the potential mechanisms: mitochondrial dysfunction and systemic inflammation.

Background: Non-alcoholic fatty liver disease (NAFLD) and atrial fibrillation (AF) are major health burdens, with emerging evidence suggesting NAFLD as a significant risk factor for AF, but the mechanism is remain unclear. Methods: In this study, we analyzed gene expression data from NAFLD (GSE89632) and AF (GSE75092) datasets from the Gene Expression Omnibus. We identified co-upregulated and co-downregulated genes between NAFLD and AF, assessed diagnostic potential of specific genes, conducted immune infiltration analysis, and performed molecular docking studies with sodium glucose co-transporter 2 inhibitors (SGLT2i). Results: We identified eight co-upregulated and 31 co-downregulated genes between NAFLD and AF. Genes such as AMOT, PDE11A, TYMS, TMEM98, and PTGS2 demonstrated substantial diagnostic potential for identifying NAFLD patients at risk of AF. Immune infiltration analysis discovered an elevated presence of CD8 T cells, γδ T cells, and M2 macrophages in NAFLD livers, linking systemic inflammation to NAFLD and AF. Additionally, studies have shown that a connection between mitochondrial dysfunction and several hub genes like DGAT1, TYMS, and PTGS2, suggesting that mitochondrial disturbances may underpin the systemic inflammation in NAFLD, which possibly exacerbating AF. Molecular docking studies indicated that empagliflozin's binding affinity with key genes such as DGAT1, TYMS, and PTGS2 presents a novel therapeutic avenue for NAFLD-associated AF. Conclusion: Our study firstly discovered that AMOT, PDE11A, TYMS, TMEM98, and PTGS2 are associated with NAFLD-related AF and hold strong diagnostic values. Our study also indicates that mitochondrial dysfunction and systemic inflammation may be potential mechanisms bridging NAFLD and AF. Additionally, we identified empagliflozin as a potentially effective therapeutic agent for NAFLD-related AF at the molecular structure level. These novel insights contribute to the further understanding, diagnosis, and intervention of NAFLD-related AF.

Identification and Verification of Biomarkers and Immune Infiltration in Obesity-Related Atrial Fibrillation.

Obesity is an independent risk factor for atrial fibrillation (AF). However, the mechanisms underlying this crosstalk are still being uncovered. Co-differentially expressed genes (co-DEGs) of AF and obesity microarrays were identified by bioinformatics analysis. Subsequently, functional enrichment, cell-type enrichment, and protein-protein interaction network analyses of co-DEGs were carried out. Then, we validated the hub genes by qRT-PCR of patients' blood samples. Finally, CIBERSORT was utilized to evaluate the AF microarray to determine immune infiltration and the correlation between validated hub genes and immune cells. A total of 23 co-up-regulated DEGs in AF and obesity microarrays were identified, and these genes were enriched in inflammation- and immune-related function. The enriched cells were whole blood, CD33+ myeloid, and CD14+ monocytes. The hub genes were identified as MNDA, CYBB, CD86, FCGR2C, NCF2, LCP2, TLR8, HLA-DRA, LCP1, and PTPN22. All hub genes were only elevated in blood samples of obese-AF patients. The CIBERSORT analysis revealed that the AF patients' left atrial appendage had increased infiltration of naïve B cells and decreased infiltration of memory B cells. The hub genes were related positively to naïve B cells and negatively to memory B cells. Ten hub genes may serve as biomarkers for obesity-related AF. These findings may also aid in comprehending pathophysiological mechanisms for obesity-related AF.

Effects of apocynin on ISO-induced delayed afterdepolarizations in rat atrial myocytes and the underlying mechanisms.

We aimed to investigate the effect of apocynin (APO) on delayed afterdepolarizations (DADs) in rat atrial myocytes and the underlying mechanisms. Rat atrial myocytes were isolated by a Langendorff perfusion apparatus. DADs were induced by isoproterenol (ISO). Action potentials (APs) and ion currents were recorded by the whole-cell clamp technique. The fluorescent indicator fluo-4 was used to visualize intracellular Ca2+ transients, and western blotting was used to measure the expression of related proteins. The incidence of DADs in rat atrial myocytes increased significantly after ISO treatment, leading to an increased incidence of triggered activity (TA). The incidence of ISO-induced DADs and TA were reduced by 100.0 µM APO from 48.89% to 25.56% and 17.78% to 5.56%, respectively. In the range of 3.0 µM-300.0 µM, the effect of APO was concentration dependent, with a half maximal inhibitory concentration (IC50) of 120.1 µM and a Hill coefficient of 1.063. APO reversed the increase in transient inward current (Iti) and Na+/Ca2+-exchange current (INCX) densities induced by ISO in atrial myocytes. The frequency of spontaneous Ca2+ transients in atrial myocytes was reduced by 100.0 µM APO. Compared with ISO, APO downregulated the expression of NOX2 and increased the phosphorylation of PLNSer16 and the sarcoplasmic reticulum Ca2+-ATPase-2a (SERCA2a) level; however, it had little effect on ryanodine-receptor channel type-2 (RyR2). These findings showed that APO may block Iti and INCX and reduce intracellular Ca2+ levels in rat atrial myocytes, thus reducing the incidence of ISO-induced DADs and TA.

Transition of Metabolic Phenotypes and Risk of Atrial Fibrillation According to BMI: Kailuan Study.

Objective: Atrial fibrillation (AF) is associated with both obesity and its metabolic consequences. However, there is a paucity of information on whether the dynamic change of metabolic health and obesity phenotypes affect the risk of AF. We aimed to prospectively examine the association between metabolic health and its change over time and AF risk across body mass index (BMI) categories. Methods: A total of 58,483 participants without history of cancer, and cardiovascular diseases from the Kailuan study were included in the present study. Transition of metabolic phenotypes was evaluated between 1st survey (2006-2007) and the 2nd survey (2008-2009). The hazard ratios (HRs) and 95% confidence intervals (CIs) for AF were assessed by Cox proportional hazards regression. Results: During a median follow-up of 3 years, we documented 580 cases of AF. Compared with metabolically healthy individuals with normal weight, the multivariable-adjusted hazard ratios for metabolically healthy and unhealthy overweight/obese were 1.27 (95% CI: 1.01, 1.59) and 1.37 (95% CI: 1.09, 1.72), respectively. However, when transition was taken into account, overweight/obese people who maintained metabolically healthy status were not associated with increased long-term risk (HR, 1.11;95% CI: 0.70, 1.78), whereas participants who converted from metabolically healthy overweight/obese status to an unhealthy phenotype had higher AF risk than those who maintained metabolically healthy normal weight (HR 1.59, 95% CI: 1.11, 2.26). When BMI and metabolically healthy status were updated over the course of the study, significant short-term elevations in AF risk were associated with individuals with stable MU-OW/OB status. Conclusion: In this community-based cohort study, metabolically healthy overweight/obese individuals have increased risks of AF. Obesity remains a risk factor for AF independent of major metabolic factors. Our data further suggested that metabolic phenotype was a dynamic condition, and maintenance of metabolic health and normal weight might alleviate the risk of AF.

Elevated levels of body mass index and waist circumference, but not high variability, are associated with an increased risk of atrial fibrillation.

BACKGROUND: Although obesity has been associated with risk of atrial fibrillation (AF), the associations of variability of obesity measures with AF risk are uncertain, and longitudinal studies among Chinese population are still lacking. We aimed to evaluate the impacts of obesity and variability of body mass index (BMI) and waist circumference (WC) on the risk of atrial fibrillation (AF) in a large Chinese cohort study. METHODS: A total of 44,135 participants of the Kailuan Study who were free of cancer and cardiovascular disease and underwent three consecutive surveys from 2006 to 2010 were followed for incident AF until 2020. Average BMI and WC over time and variability were calculated. Cox proportional hazards regression models were used to assess hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of obesity and variability in BMI and WC with AF risk. RESULTS: During a mean follow-up of 9.68 years, there were 410 cases of incident AF. In multivariable-adjusted models, compared with normal BMI/WC, individuals with general obesity and abdominal obesity had increased risk of AF, with corresponding HRs of 1.73 (95% CI: 1.31-2.30) and 1.38 (95% CI: 1.11-1.60), respectively. The short-term elevation in AF risk persisted for the obese even after adjustment for updated biologic intermediaries and weight. Variability in BMI and WC were not associated with the risk of AF. The restricted cubic spline models indicated significant linear relationships between levels of WC and BMI and risk of AF. CONCLUSIONS: Elevated levels of BMI and WC were associated with an increased risk of AF, whereas variability in BMI and WC were not. Therefore, achieving optimal levels of BMI and WC could be valuable in AF prevention.

EDIL3 deficiency ameliorates adverse cardiac remodelling by neutrophil extracellular traps (NET)-mediated macrophage polarization.

AIMS: After myocardial infarction (MI), injured cardiomyocytes recruit neutrophils and monocytes/macrophages to myocardium, which in turn initiates inflammatory and reparative cascades, respectively. Either insufficient or excessive inflammation impairs cardiac healing. As an endogenous inhibitor of neutrophil adhesion, EDIL3 plays a crucial role in inflammatory regulation. However, the role of EDIL3 in MI remains obscure. We aimed to define the role of EDIL3 in cardiac remodelling after MI. METHODS AND RESULTS: Serum EDIL3 levels in MI patients were negatively associated with MI biomarkers. Consistently, WT mice after MI showed low levels of cardiac EDIL3. Compared with WT mice, Edil3-/- mice showed improvement of post-MI adverse remodelling, as they exhibited lower mortality, better cardiac function, shorter scar length, and smaller LV cavity. Accordingly, infarcted hearts of Edil3-/- mice contained fewer cellular debris and lower amounts of fibrosis content, with decreased collagen I/III expression and the percentage of α-smooth muscle actin myofibroblasts. Mechanistically, EDIL3 deficiency did not affect the recruitment of monocytes or T cells, but enhanced neutrophil recruitment and following expansion of pro-inflammatory Mertk-MHC-IIlo-int (myeloid-epithelial-reproductive tyrosine kinase/major histocompatibility complex II) macrophages. The injection of neutrophil-specific C-X-C motif chemokine receptor 2 antagonist eliminated the differences in macrophage polarization and cardiac function between WT and Edil3-/- mice after MI. Neutrophil extracellular traps (NETs), which were more abundant in the hearts of Edil3-/- mice, contributed to Mertk-MHC-IIlo-int polarization via Toll-like receptor 9 pathway. The inhibition of NET formation by treatment of neutrophil elastase inhibitor or DNase I impaired macrophage polarization, increased cellular debris and aggravated cardiac adverse remodelling, thus removed the differences of cardiac function between WT and Edil3-/- mice. Totally, EDIL3 plays an important role in NET-primed macrophage polarization and cardiac remodelling during MI. CONCLUSION: We not only reveal that EDIL3 deficiency ameliorates adverse cardiac healing via NET-mediated pro-inflammatory macrophage polarization but also discover a new crosstalk between neutrophil and macrophage after MI.

Preparation and evaluation of lecithin/zein hybrid nanoparticles for the oral delivery of Panax notoginseng saponins.

Panax Notoginseng Saponins (PNS) has been widely used in the prevention and treatment of cardiovascular and cerebrovascular diseases such as myocardial infarction, heart failure and cerebral infarction. However, oral administration of PNS showed low bioavailability because of its instability and poor membrane permeability in the gastrointestinal tract. Here, lipoprotein-inspired hybrid nanoparticles of PNS-Lecithin-Zein (PLZ-NPs) were prepared by using a simple phase separation method, which possessed a core-shell structure, where zein was used as protein part to replace the animal origin protein to increase the resistance to acid and enzymes while lecithin was used as the lipid composition to improve the oral absorption of PNS as well as to increase the drug loading capacity of PNS into the nanocarriers. The results of stability test showed that PLZ-NPs had robust enzymolysis resistance ability for acid and digestive enzymes of gastrointestinal environments. The fluorescent resonance energy transfer (FRET) assay confirmed the ability of LZ-NPs to be intactly absorbed by Caco-2 cell monolayer. Cell transport studies demonstrated that the permeability of PLZ-NPs in Caco-2/HT29-MTX co-culture cell model was 1.5-fold that of PNS. Meanwhile, the single-pass intestinal perfusion assay proved the absorption parameter Peff of PLZ-NPs was 1.75 and 1.80 times higher than that of PNS in the ileum and jejunum, respectively. Finally, the in vivo pharmacokinetic experiment showed that the relative oral bioavailability of PLZ-NPs was 1.71-fold that of free PNS in SD rat. In summary, the employment of the Lecithin/Zein hybrid nanoparticles could be considered as a promising approach for PNS analogues.

Multi-electrode mapping of complex macroreentry atrial tachycardia.

BACKGROUND: Multi-electrode mapping (MEM) is increasingly applied in ablation of complex atrial arrhythmias. This study aimed to evaluate MEM for analysis and treatment of complex macroreentry atrial tachycardia (MAT). METHODS: Patients with MAT related to scarring, history of heart surgery or atrial linear ablation were studied. Patients were mapped with conventional activation mapping (CAM) or MEM. After characterizing the mechanism of atrial tachycardia (AT), the ablation was performed. RESULTS: The study consisted of 114 eligible patients, 74 in the CAM and 40 in MEM. Compared with CAM, MEM had a shorter procedure duration (156.7 ±â€¯59.1 ms vs. 127.3 ±â€¯59.3 ms, P = 0.003) and mapping duration (62.6 ±â€¯35.7 ms vs. 30.5 ±â€¯15.3 ms, P < 0.001) and more mapping points (1364.9 ±â€¯828.7 points vs. 148.3 ±â€¯79.6 points, P < 0.001). There were no significant differences between CAM and MEM in acute ablation success rate, complication, postoperative AADs, and ablation duration. The mean disease-free survival time in CAM versus MEM was 20.8 (95% CI: 17.6-24.1) months versus 26.6 (95% CI: 22.7-30.4) months. The median disease-free survival time in the CAM versus MEM was 20.0 (95% CI: 13.9-26.1) months versus 30.0 (95% CI: 26.7-36.3) months. The AT recurrence risk of MEM was 0.522 times that of CAM (HR 95% CI: 0.282-0.968; P = 0.039). CONCLUSION: MEM is strongly recommended in ablation of complex MAT.

The impact of renal function on efficacy and safety of new oral anticoagulant in atrial fibrillation patients: A systemic review and meta-analysis.

BACKGROUND AND OBJECTIVES: This meta-analysis was to investigate the efficacy and safety of new oral anticoagulant (NOAC) in atrial fibrillation (AF) patients with renal function insufficiency, and to explore whether renal decline occurs in AF patients with NOAC and its impact on outcomes. METHODS AND RESULTS: In AF patients with mild renal insufficiency, the NOAC was associated with significantly lower rates of stroke (odds ratio [OR], 0.78; 95% confidence interval [CI], 0.67-0.91; P < .05). Lower rates of bleeding were significantly observed in NOAC group (OR, 0.85; 95% CI, 0.75-0.97; P < .05). In AF patients with moderate renal impairment, similar results were revealed (OR for stroke or systemic embolism, 0.80; 95% CI, 0.67-0.95, P < .05; OR for major bleeding, 0.78; 95% CI, 0.59-1.03; P = .07). During the follow-up, pooled data revealed that NOAC showed a less renal toxicity, but the difference did not reach statistical significance (creatinine clearance decline: -0.12 mL/min [-0.84, 0.61 mL/min]). We have revealed that the NOACs were associated with significantly lower rates of stroke or systemic embolism (hazard ratio [HR], 0.66; 95% CI, 0.42-0.89; P < .05) and lower rates of bleeding (HR, 0.93; 95% CI, 0.70-1.16; P = .153) in AF patients with worsening renal function. CONCLUSIONS: NOAC may have the potentiality to be at least as effective as warfarin and may equal safety outcomes in AF patients with renal impairment. Renal decline during therapeutics may be less likely happened in NOAC than warfarin dose. NOAC may reveal good efficacy and safety outcomes in these scenarios. Further detailed research is needed to gain more clear profile on this new anticoagulant.

Rapamycin loaded TPGS-Lecithins-Zein nanoparticles based on core-shell structure for oral drug administration.

Rapamycin as a novel macrolide immunosuppressive agent has been commonly used in organ transplantation owing to its stronger immunosuppressive effect, non-nephrotoxicity and lower side effect. However its drawbacks of low bioavailability and big individual difference remain to be improved in clinical application. Here rapamycin loaded TPGS-Lecithins-Zein nanoparticles (RTLZ-NPs) with core-shell structure were prepared by the phase separation method. The RTLZ-NPs were approximately 190.3 nm in size, with PDI and zeta potential about 0.256 and -19.71 mV respectively. Drug entrapment and loading achieved were about 86.64 and 25.73% respectively. Meanwhile RTLZ-NPs exhibited favorable enzymolysis resistance abilities in gastrointestinal environments and enhanced uptake in Caco-2 cells. The optimum absorption sites of rapamycin in the intestine were duodenum and jejunum as single-pass intestinal perfusion assay. Upon also considering the results of Caco-2 cell assay, it could be speculated that the transport of rapamycin in vivo involved active transport as well as P-glycoprotein (P-gp) based efflux. Finally, the relative oral bioavailability of RTLZ-NPS was 4.33 fold higher than free rapamycin in SD rat. Altogether the designed nanoparticles can be an efficient oral delivery strategy for rapamycin analogues to prevent the attacks from destructive enzymes, reduce cell efflux, increase cell uptake, and then enhance the oral bioavailability.

Impact of VKORC1, CYP4F2 and NQO1 gene variants on warfarin dose requirement in Han Chinese patients with catheter ablation for atrial fibrillation.

BACKGROUND: The anticoagulation of atrial fibrillation catheter ablation during the perioperative stage does matter and should be treated with discretion. We aimed to assess impact of three important genes participating in vitamin K cycle (i.e. VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566) on the daily stable warfarin dose requirement in Sichuan Han Chinese patients with catheter ablation of atrial fibrillation. METHODS: A total of 222 atrial fibrillation patients taking stable warfarin therapy after catheter ablation operation were enrolled in this study. The study population included had high (≥2) risk according to the CHA2DS2-VASc risk score. Genotypes of VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566 were analyzed by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Multiple linear regression analysis was applied to depict the impact of VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566 on the daily stable warfarin dose requirement. RESULTS: Carriers of VKORC1 rs9923231 AG/GG genotypes required significantly higher warfarin dose (3.03 ± 0.28 mg/day, 7.19 mg/day, respectively) than AA carriers (2.52 ± 0.07 mg/day; P < 0.001). Carriers of CYP4F2 rs2108622 CT/TT genotypes required significantly higher warfarin dose (3.38 ± 0.22 mg/day, 2.79 ± 0.19 mg/day, respectively) than CC carriers (2.41 ± 0.08 mg/day; P < 0.001). However, the warfarin dose for carriers of NQO1 rs1800566 CT/TT genotypes (2.46 ± 0.24 mg/day, 3.01 ± 0.27 mg/day, respectively) was not significantly higher than that for the CC carriers (2.33 ± 0.1 mg/day). The multiple linear regression model including genotypes and demographic characteristics, could explain 20.1% of individual variations in the daily stable warfarin dose in Sichuan Han Chinese. VKORC1 rs9923231 contributed most (15%) to the individual variations in daily stable warfarin dose, while CYP4F2 rs2108622 contributed least (3%). CONCLUSION: NQO1 rs1800566 is not a significant genetic factor of warfarin dose for Han Chinese, whereas VKORC1 rs9923231 and CYP4F2 rs2108622 are significant genetic factors, which could explain 15% and approximately 3% of individual variations in the daily stable warfarin dose respectively.

The effects of patients initiated aggression on Chinese medical students' career planning.

BACKGROUND: Patient initiated aggression is common among Chinese health-care workers, reaching over 10,000 incidents annually (Jinyang web. http://6d.dxy.cn/article/55497 . 2013), and the tense doctor-patient relationship generates stress among medical students. Because of the paucity of data (few surveys pay attention to the effects of violence perpetrated by patients on medical students), this study aimed to characterize patient initiated aggression against medical students. METHODS: In this cross-sectional survey conducted at a medical school in West China in 2015, 157 medical students completed a self-administered questionnaire and the Short Form-36, which assesses quality of life. The associations between patient initiated aggression exposure and medical students' career planning or quality of life were assessed using a chi-square test. RESULTS: Of the 157 medical students, 48 (30.6%) reported having suffered patient initiated aggression at least once during the previous year in the form of mental abuse (20.4%), offensive threat (14.6%), physical violence (8.3%), sexual harassment (verbal: 8.3% or physical: 1.6%), and extreme violence (physical violence leading to surgical treatment or hospitalization) (0.6%). Insufficient communication was the primary reason cited (27.2%). Emotional attack (mental abuse and offensive threat) occurrence differed among age groups (χ2 = 9.786, P = 0.020) and was ubiquitous among those aged >30 years old. Women were more likely than men to suffer physical violence (χ2 = 6.796, P = 0.009). Patient initiated aggression was not significantly associated with medical students' career planning or quality of life. CONCLUSIONS: In this study, patient initiated aggression, albeit common, as in the rest of China, did not appear to be associated with medical students' career planning or quality of life. However, the characteristics described can inform policymaking and the design of programs to minimize patient initiated aggression occurrence.