Background and aims Arginine (Arg) and homoarginine (hArg) are related to the nitric oxide pathway, which is important for vascular function. We investigated if serum concentrations of Arg and hArg predicted long-term cardiovascular disease (CVD) mortality in patients with chronic coronary syndrome (CCS), and whether associations differed between non-obstructive coronary artery disease (NOCAD) and obstructive coronary artery disease (OCAD). Methods and results We included 4164 patients undergoing invasive coronary angiography for suspected CCS. Associations with CVD mortality were assessed using multivariable Cox regression, reporting hazard ratios (HRs) per standard deviation increase in log-transformed concentrations. During a median follow-up of 14.1 years, 586 (14.1%) patients died from CVD. Serum hArg was inversely associated with CVD mortality [HR (95% CI): 0.81 (0.74–0.88)] as was serum Arg [HR (95% CI): 0.90 (0.83–0.98)]. However, in Fine–Gray competing risk analyses, the association of serum Arg with CVD mortality was no longer statistically significant, whereas the inverse association for serum hArg persisted. Addition of serum hArg to the clinical model increased the C-statistic from 0.771 to 0.776, indicating a modest improvement in discrimination. In exploratory subgroup analyses, the association between serum hArg and CVD mortality was stronger in NOCAD than OCAD [0.54 (0.40–0.73) vs. 0.84 (0.77–0.92); P for interaction = 0.037]. Conclusion Serum Arg and hArg were inversely associated with long-term CVD mortality in patients with CCS. However, the association of serum hArg was more robust than that of serum Arg. The stronger association observed in NOCAD requires independent validation.
Background and objective Endothelial-to-mesenchymal transition (EndMT) is a crucial process driving vascular remodeling in atherosclerosis (AS). N6-methyladenosine (m6A) RNA methylation, regulated by YTH N6-methyladenosine RNA binding protein F1 (YTHDF1), an m6A reader that modulates RNA stability and translation, influences various cellular functions, but its specific role in AS-related EndMT remains unclear. This study aimed to investigate the role of the m6A reader YTHDF1 in AS progression, focusing on its regulation of bromodomain containing 4 (BRD4), a central epigenetic regulator in the Bromodomain and Extra-Terminal (BET) family, and subsequent promotion of EndMT. Methods Human AS datasets (involving 6 clinical samples in GSE97210 and 104 clinical samples in GSE100927) and single-cell RNA sequencing data from Apoe−/− mice (n = 3 in total) were analyzed to assess YTHDF1 expression and correlation. YTHDF1−/−Apoe−/− mice (n = 5) were generated and fed a high-fat diet to evaluate plaque formation. In vitro, human umbilical vein endothelial cells (HUVECs) were used for gain/loss-of-function experiments. Methylated RNA immunoprecipitation (MeRIP), RNA immunoprecipitation (RIP), site-directed mutagenesis, and functional assays (Transwell, wound healing) were employed to elucidate the molecular mechanism. Results YTHDF1 was significantly upregulated in human AS plaques (P < 0.001) and positively correlated with EndMT markers. ScRNA-seq analysis revealed a progressive increase in YTHDF1-expressing endothelial cells during plaque progression in Apoe−/− mice. YTHDF1 knockout in Apoe−/− mice markedly reduced atherosclerotic lesion area (P = 0.0023), lipid deposition (P = 0.0007), and en face plaque area (P = 0.0038), accompanied by attenuated EndMT. In HUVECs, YTHDF1 overexpression promoted EndMT, enhanced cell migration (P < 0.01), and upregulated BRD4 (1.53 ± 0.20vs.1 ± 0.19 in control, p = 0.027). Mechanistically, METTL3-mediated m6A modification at a specific site in the 5′-UTR of BRD4 mRNA was recognized by YTHDF1, which stabilized BRD4 transcripts and increased BRD4 protein levels. Conversely, BRD4 knockdown suppressed the EndMT phenotype and impaired HUVEC migration (P < 0.01). Conclusion Our findings uncover a novel pathogenic axis in AS where YTHDF1, by recognizing METTL3-mediated m6A modification on BRD4 mRNA, enhances its stability. This leads to increased BRD4 expression, which in turn drives EndMT and exacerbates disease progression. The YTHDF1-m6A-BRD4 pathway may represent a potential therapeutic target for AS which requires further preclinical validation.
Background Low-density lipoprotein cholesterol (LDL-C) remains central to lipid-based cardiovascular risk assessment, but LDL-C alone may not fully capture residual atherogenic lipoprotein burden. Small dense LDL cholesterol (sdLDL-C) is influenced by LDL-C and triglyceride (TG)-rich lipoprotein metabolism, and elevated sdLDL-C may be overlooked when LDL-C is not elevated. Whether LDL-C/sdLDL-C discordance differs by sex across TG strata remains unclear. Methods This cross-sectional study included 1879 Japanese adults undergoing annual health check-ups in 2020. The primary analysis included participants with LDL-C <140 mg/dL. Discordance was defined as sdLDL-C ≥35 mg/dL. Discordance prevalence was compared between men and women overall and across TG strata. Apolipoprotein B (ApoB), malondialdehyde-modified LDL (MDA-LDL), high-density lipoprotein 2 cholesterol (HDL2-C), high-density lipoprotein 3 cholesterol (HDL3-C), the HDL2-C/HDL3-C ratio, and high-molecular-weight adiponectin (HMW-adiponectin) were compared by discordance status. Results Among participants with LDL-C <140 mg/dL, discordance was more frequent in men than in women [259/917 (28.2%) vs. 42/438 (9.6%), P < 0.001]. This sex difference persisted at TG < 150 mg/dL [16.0% vs. 4.2%, P < 0.001] and TG < 100 mg/dL [7.5% vs. 2.4%, P = 0.0015], but not at TG ≥ 150 mg/dL [74.1% vs. 71.4%, P = 0.835]. Discordant participants had higher ApoB and MDA-LDL and lower HDL2-C, HDL2-C/HDL3-C ratio, and HMW-adiponectin. Conclusions LDL-C/sdLDL-C discordance was more frequent in men, particularly in lower TG strata, and was accompanied by an adverse atherogenic lipid profile.
Introduction Clonal hematopoiesis (CH), defined as the expansion of a subset of hematopoietic stem or progenitor cells driven by acquired mutations, represents a novel cardiovascular risk factor. Its role in patients with high-grade carotid stenosis remains to be evaluated. Patients and methods Next-generation sequencing (NGS) involving 30 genes implicated in CH was used as diagnostic-grade assay (SOPHiA DDM Myeloid Solution) to screen for CH in 83 prospectively collected patients with symptomatic or asymptomatic high-grade carotid stenosis undergoing carotid endarterectomy (CEA). Results Clonal markers were detected in 16 (19.7 %) of 83 patients (median age 71.2 years), with prevalence increasing at advanced age. At 5-year follow-up, CH carriers showed a higher cumulative incidence of major adverse cardiovascular events (MACE; P = 0.040) compared to patients without CH; all-cause mortality did not differ significantly between groups (P = 0.57). Cox regression revealed a significant association between CH and MACE in a univariable model (P = 0.047), which remained significant after multivariable adjustment for age and sex (P = 0.018). Exploratory analyses suggested that the association between CH and MACE may differ according to carotid stenosis severity, with an increased incidence of MACE observed in patients with <90 % stenosis and concomitant CH, an effect absent in patients with ≥90 % stenosis (Pinteraction = 0.03). Discussion and conclusions CH was associated with an adverse 5-year outcome in patients with carotid artery stenosis. These findings identify CH as a hematologic contributor to post-interventional cardiovascular risk and indicate that assessment of CH may offer additional prognostic information for residual risk stratification.
Background and Aims Elevated lipoprotein(a) [Lp(a)] levels are recognized as a genetic risk factor for atherosclerotic cardiovascular disease. Previous coronary imaging studies have linked elevated Lp(a) levels to vulnerable coronary plaque characteristics. However, the relationship between elevated Lp(a) levels and vulnerable aortic plaque characteristics remains unclear. We investigated the association between serum Lp(a) levels and vulnerable aortic plaque characteristics assessed by non-obstructive general angioscopy (NOGA). Methods We analyzed 276 consecutive patients with coronary artery disease who underwent NOGA between December 2014 and March 2023. Patients were divided according to serum Lp(a) levels using a 30 mg/dL cutoff. Vulnerable aortic plaque characteristics, including plaque rupture, thrombus, yellow plaque, ulceration, and fissure, were assessed by NOGA. Results Elevated Lp(a) levels (>30 mg/dL) were observed in 27% of patients, whereas markedly elevated Lp(a) levels (>50 mg/dL) were observed in 14%. Patients with elevated Lp(a) levels showed a significantly higher prevalence of plaque rupture (84% vs. 62%, p<0.001), thrombus, and fissure than those with lower Lp(a) levels. In contrast, the prevalence of yellow plaque did not differ significantly between groups. The prevalence of plaque rupture progressively increased according to Lp(a) strata. In multivariate logistic regression analysis, elevated Lp(a) levels remained independently associated with plaque rupture after adjustment for traditional cardiovascular risk factors. Conclusions Elevated serum Lp(a) levels were independently associated with aortic plaque rupture assessed by NOGA. These findings suggest that elevated Lp(a) levels may be associated with persistent aortic plaque vulnerability despite intensive LDL-C lowering.
