Atherosclerosis

BackgroundEvolocumab promotes coronary plaque regression in patients with coronary artery disease, but little is known regarding carotid plaques (CP). This study aimed to evaluate the impact of evolocumab on top of lipid-lowering therapy (ELLT) on carotid morphological stabilization (MS) and plaque regression (PR) compared to lipid-lowering therapy (LLT) alone. MethodsAsymptomatic patients with internal carotid stenosis[≥]50% and LDL-C[≥]100 mg/dL were randomized to ELLT or LLT and monitored by serial duplex ultrasound. The primary endpoint was a composite of 6-month-MS (i.e., switch from morphologic types I-II to III-IV) and/or 12-month-PR (i.e., reduction of carotid stenosis by at least 5% compared to baseline). The secondary endpoint was LDL-C change at 12 months. Major adverse vascular events (MAVE, i.e., cardiac death, stroke, myocardial infarction, carotid or coronary or peripheral revascularization) were recorded. ResultsA total of 170 patients were randomized. Mean carotid stenosis was 57%. At 6 months, MS occurred in the ELLT group (10.3%) only (p=0.29). At 12 months, PR was numerically more frequent in the ELLT group, without reaching statistical significance (43% versus 35.1%, p=0.42). The primary endpoint was met in 44.3% versus 35.1% (p=0.26). As compared to baseline, 6 and 12-month shifts from low to high-risk types were significantly higher in the LLT group (p=0.03). The 12-month LDL-C percentage reduction was -73.5% with ELLT, and -48.3% with LLT (p=0.0001). At 1 year, MAVE were significantly more frequent with LLT (14.6% versus 2.4%, p=0.005), and the absence of evolocumab was the only predictor (OR 7, p=0.014). ConclusionsIn patients with CP[≥]50% and LDL-C[≥]100 mg/dL, ELLT compared to LLT was associated with numerically but not statistically higher 6-month MS and/or 12-month PR. In the LLT group, 6- and 12-month changes from low to high-risk types, LDL-C, and MAVE were significantly higher. According to these results, evolocumab should be considered standard treatment for patients with CP[≥]50%. The study was registered at www.clinicaltrials.gov (NCT04730973) and Eudract (2020-005663-31). SHORT ABSTRACTPatients with carotid stenosis[≥]50% and LDL-C[≥]100 mg/dL were randomized to evolocumab on top of optimal lipid-lowering therapy (ELLT) or optimal lipid-lowering therapy (LLT) alone to assess the impact of ELLT on carotid plaque morphological stabilization (MS) and plaque regression (PR). At 6 and 12 months, MS and PR occurred in both groups, but were numerically higher in the ELLT group, without reaching statistical significance. In the LLT group, 6- and 12-month changes from low to high-risk types were significantly higher, and the rate of adverse vascular events was sevenfold higher. Evolocumab might become the standard treatment for patients with carotid artery stenosis [≥]50%. CLINICAL PERSPECTIVEO_ST_ABSWhat is new?C_ST_ABSO_LIThe CARUSO is the largest randomized trial evaluating the impact of evolocumab on top of lipid-lowering therapy (ELLT) on carotid morphological stabilization (MS) and plaque regression (PR) monitored by serial duplex ultrasound. C_LIO_LIThe primary endpoint was a composite of 6-month-MS (i.e., switch from morphologic types I-II to III-IV) and/or 12-month-PR (i.e., reduction of carotid stenosis by at least 5% compared to baseline) and was numerically higher in the ELLT group compared to lipid-lowering therapy (LLT) alone, without reaching statistical significance. C_LIO_LIThe 1-year rate of major adverse vascular events (MAVE) was sevenfold higher in the LLT group. C_LI What are the clinical implications?O_LICarotid plaque morphology is a dynamic event, and 6 and 12-month shifts from low to high-risk morphological types were significantly higher in the LLT group, thus suggesting that evolocumab added to LLT may prevent morphological deterioration. C_LIO_LIThe absence of evolocumab was the only independent predictor of MAVE; according to our results, ELLT might become the standard treatment for patients with carotid plaques [≥]50% and LDL-C not at target. C_LIO_LIFuture larger studies are warranted to validate our findings, assess long-term adherence to therapy, and identify subgroups with higher probability of achieving MS and PR. C_LI

Atherosclerosis is a condition characterized by plaque growths in arteries, consisting of oxidized LDL (low-density lipoprotein) and localized cell cumulation. By the time of diagnosis for patients with atherosclerosis, the disease has often progressed into advanced stages. Statins are commonly prescribed; however, while these drugs can lower blood cholesterol levels, they cannot regress or stop the plaque growth. Currently, there are no treatments available to prevent the formation of new plaques. Such treatment options would require the identification of proteins that act during disease onset, initiating molecular mechanisms that promote plaque formation. Histone deacetylases (HDACs) and Ten Eleven Translocation (TET) demethylases are two important classes of epigenetic mediators. Some isoforms of these two classes of proteins have been found to transcriptionally regulate cellular inflammation, which may favor plaque formation. These transcriptional regulators seem to function early in the molecular mechanisms that are involved in disease progression. In the present work, we identified a clear role of these epigenetic proteins in foam cell formation. Foam cells have been implicated as part of the early steps which ultimately lead to atherosclerosis. Here we showed that in the presence of OxLDL (oxidized LDL), the protein isoform TET1 has a direct role in foam cell formation, while HDAC2 adopts a more indirect role. Using specific inhibitors of TET1 and HDAC2, we showed the inter-regulated molecular mechanisms between these proteins and how they regulate foam cell formation in vitro. In this study, we found that upon inhibition of TET1 in U937-derived macrophages, and subsequent foam cell formation via OxLDL treatment, a lower percentage of foam cells was observed. However, TET2 inhibition under the same treatment conditions had no effect on the inhibition of foam cell formation.

BackgroundElevated low-density lipoprotein cholesterol (LDL-C) is a risk factor for cardiovascular disease. Despite available lipid-lowering therapies (LLT), lipid control remains suboptimal. Bempedoic acid offers a non-statin oral treatment for hypercholesterolemia. However, real-world data in Asia are limited. The study aimed to investigate the effectiveness and safety of bempedoic acid in Taiwan. MethodsThis pragmatic phase IV study enrolled 180 patients with inadequately controlled hypercholesterolemia to receive bempedoic acid for 12 weeks in addition to background LLT. The primary endpoint was the percentage change in LDL-C. Secondary endpoints included changes in other lipid parameters, high-sensitivity C-reactive protein (hsCRP), and safety outcomes. ResultsAmong 180 patients, 160 (88.9%) completed the study. The median percentage change in LDL-C from baseline to week 12 was -19% (interquartile range [IQR]: -36.4% to -3.6%), decreasing from 117.5 to 92 mg/dL (p < 0.01). The median percentage changes from baseline to week 12 were -13.3% for non-high-density lipoprotein cholesterol (non-HDL-C), -10.8% for total cholesterol, -11.5% for apolipoprotein B, and -34.0% for hsCRP (all p < 0.01). Minimal effects were noted on triglycerides (+0.2%), HDL-C (-5.5%), and lipoprotein(a) (+2.6%) (all p > 0.05). At week 12, 31.3% of patients achieved LDL-C targets (< 100 mg/dL for primary prevention; < 55 or < 70 mg/dL for secondary prevention). The safety outcomes were consistent with the locally approved label, with no new safety signals identified. ConclusionsBempedoic acid offers an effective and safe oral therapeutic option for Taiwanese patients whose LDL-C levels remain inadequately controlled with existing LLT, including statins. RegistrationURL: https://clinicaltrials.gov/study/NCT06925100; Unique identifier: NCT06925100 Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABS{diamondsuit} This pragmatic phase IV study provides the first real-world evidence from Taiwan demonstrating that bempedoic acid leads to clinically meaningful reductions in LDL-C (median percentage change: -19%) at week 12 when added to background lipid-lowering therapy in patients with inadequately controlled hypercholesterolemia. {diamondsuit}Approximately one-third of patients achieved guideline-recommended LDL-C targets within 12 weeks, with a safety profile consistent with the locally approved label and no new safety signals identified. What Are the Clinical Implications?{diamondsuit} Bempedoic acid represents an effective and well-tolerated oral add-on lipid-lowering option for Taiwanese patients who fail to achieve LDL-C goals with existing therapies, including those unable to tolerate or intensify statin treatment.

Background: Vascular smooth muscle cells (VSMCs) phenotypic plasticity can modulate atherosclerosis progression. Although several gene regulatory steps towards pro-inflammatory phenotypes have been well-studied, epitranscriptomic changes during this transition and their regulatory roles remain unexplored. Methods and Results: Primary human VSMCs were stimulated with TGF-{beta}1 to induce an atheroprotective, contractile, and matrix-producing state and with IL1-{beta} plus PDGF-BB to induce a highly energetic, pro-inflammatory state, confirmed by Illumina bulk RNA sequencing and proteomics. Untargeted screening of mRNA base modifications using Oxford Nanopore Technologies direct RNA sequencing and xPore analysis revealed enhanced uridine modification within a GUUUU motif in pro-inflammatory VSMCs. Modified uridines were enriched in 3'-UTR and accessible RNA structures, with implications on Poly(A) tail dynamics and miRNA binding. Conclusions: Atheroprotective and pro-atherogenic treatments induce distinct epitranscriptomic landscapes composed of different modification types, often co-localized in the same transcript. Modified uridines in mRNAs are abundant in a high-energy, pro-inflammatory VSMC state and associated with post-transcriptional regulation. In summary, epitranscriptomics adds a novel regulatory layer to VSMC phenotypic transitions critical for atherosclerosis development and progression.

BackgroundHDL particles can carry microRNAs (miRNAs), capable of regulating gene expression connected to HDL functions. Despite links to some cardiovascular risk factors, miRNA association with incident acute myocardial infarction (AMI) remains unclear. ObjectivesOur aim was to elucidate the association between HDL-bound miRNAs (HDL-miRNAs) and incident AMI using a non-targeted approach in a population-based study. MethodsWe conducted a case-cohort study including 247 participants from the REGICOR cohort in northeastern Spain (51 AMI cases and a random sample of 196 participants, including seven overlapping AMI cases). HDL-miRNAs were isolated from apolipoprotein B-depleted serum and quantified by whole-genome miRNA sequencing. Associations between HDL-miRNAs and incident AMI were assessed using multivariable Cox proportional hazards model. For AMI-associated HDL-miRNAs (p-value <0.10), we retrieved their experimentally validated targets and assessed pathway enrichment of these targets via over-representation analysis. ResultsTwo HDL-miRNAs were associated with incident AMI after FDR correction: miR-628-3p (HR 1.69, 95% CI 1.30 to 2.19) and miR-28-3p (HR 1.58, 95% CI 1.21 to 2.06). Nine additional HDL-miRNAs were nominally associated with AMI incidence (p-value <0.05), eight with a direct association (miR-93-5p, miR-26b-5p, miR-106a-5p, miR-126-3p, miR-15b-5p, let-7a-5p, let-7e-5p, and let-7f-5p) and one with an inverse association (miR-361-5p). These miRNAs regulate the expression of genes in pathways involved in cholesterol regulation, particularly cholesterol efflux and homeostasis. The AMI group exhibited higher variance and a greater number of significant and strong correlations. ConclusionsTwo HDL-miRNAs (miR-628-3p and miR-28-3p) were significantly associated with AMI incidence. A tighter coregulatory network in cases was observed, underscoring their potential clinical utility in risk prediction and cardiovascular prevention. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSO_LIIn a population-based case-cohort study we profiled the HDL-bound miRNome and found two miRNAs (miR-628-3p and miR-28-3p) associated with incident AMI. C_LIO_LIThe use of HDL-enriched serum fractions provided a focused analysis on HDL functionality. These miRNAs regulate the expression of genes in pathways involved in cholesterol efflux and homeostasis (ABCA1, ARL4C, SIRT1, NFKBIA, ANXA2, LRP6) and show a tighter coregulatory network among significant miRNAs among cases, supporting biological coherence. C_LI What Are the Clinical Implications?O_LIHDL-miRNA signatures may complement traditional risk factors to refine AMI risk stratification and provide a rationale for HDL-guided, miRNA-targeted preventive interventions using HDL-like delivery platforms. C_LI

Atherosclerotic plaques accumulate low-density lipoprotein (LDL) together with antibodies targeting LDL and its apolipoprotein B (apoB) component. Given the association between IgG and plaque vulnerability, we hypothesized that apoB-specific immune complexes actively promote plaque destabilization. Using immunohistochemistry in carotid endarterectomy specimens, we quantified antibody deposition across morphologically defined plaque regions, and measured apoB reactivity and immune complex levels in matched plaque and plasma samples. IgG deposition was strongly associated with thin fibrous caps, reduced collagen content, and higher overall plaque vulnerability. Symptomatic patients exhibited increased apoB-specific IgG and reduced apoB-IgG immune complexes within plaques, indicating enhanced IgG recycling and heightened inflammatory activity. The neonatal Fc receptor (FcRn) was predominantly expressed by CD163+ macrophages, and mediated antibody recycling, LDL uptake, and production of tumor necrosis factor (TNF) and matrix metalloproteinase-9 (MMP-9) in vitro. Plaque FcRn expression increased with age and correlated with mediators of vulnerability, including collagen-degrading enzymes and pro-inflammatory cytokines. Ex vivo treatment of human plaques with a clinically used FcRn-blocking monoclonal antibody reduced IgG recycling and suppressed TNF and MMP-9 production. These findings identify FcRn-dependent antibody recycling as a contributor to inflammatory plaque vulnerability and highlight FcRn as a potential therapeutic target in atherosclerosis.

BackgroundThe comparative roles of triglyceride-rich lipoproteins (TRLs) and low-density lipoproteins (LDLs) in abdominal aortic aneurysm (AAA) pathogenesis are unclear. ObjectivesTo evaluate the putative causal role of TRLs in AAA, quantify the relative effect on AAA risk ("aneurysmogenicity") of TRL vs LDL particles, and prioritize lipid-lowering drug targets for AAA prevention and treatment. MethodsWe performed summary-level and individual-level Mendelian randomization (MR) analyses. Genetic variants were selected from 383,983 UK Biobank participants and ranked into 10 sets of variants where set 1 predominantly affected LDL cholesterol (LDL-C) and set 10 predominantly affected TRL cholesterol (TRL-C; and with mixed effects for intermediate variant sets). AAA outcome data were obtained from AAAgen (37,214 cases), FinnGen (4,439 cases), and the VA Million Veteran Program (MVP; 23,848 cases). Multivariable MR was used to assess the independent roles of LDL-C and TRL-C in AAA. For each set of variants, MR or logistic regression was used to estimate AAA odds ratios (ORs) per 10 mg/dL higher apolipoprotein B (apoB). Interaction analyses were conducted between a statin-like LDL-C-lowering variant set (set 3) and a TRL-C-lowering variant set (set 10). Drug-target MR was performed to evaluate lipid-lowering targets relevant to LDL-C- and TRL-C-lowering. ResultsGenetically predicted LDL-C and TRL-C concentrations were each associated independently with genetic liability for AAA after mutual adjustment, with 3.0 to 5.5 times stronger associations for TRL-C compared to LDL-C on a per-cholesterol basis. In AAAgen, the AAA OR per 10 mg/dL increased apoB concentrations were 1.10 (95% CI, 1.05-1.14) for variant set 1 (LDL-C-predominant) and 1.89 (95% CI, 1.69-2.11) for variant set 10 (TRL-C-predominant). Using the ratio of log(OR) per 10 mg/dL apoB for set 10 versus set 1 as a conservative estimate of relative aneurysmogenicity, TRLs were approximately 3.2 to 6.9 times more aneurysmogenic than LDLs across the three studies. No evidence of interaction was observed between LDLs and TRLs, indicating additive contribution to AAA risk. Drug-target MR supported strong protective associations for genetically proxied inhibition of TRL-pathway targets, particularly APOC3 and LPL, with AAA risk. ConclusionsTRLs are at least threefold more aneurysmogenic than LDLs on a per-particle basis. Therapeutic strategies targeting TRL-C --especially via APOC3 and LPL--should be prioritized for AAA prevention and treatment.

BackgroundFamilial dysbetalipoproteinemia (FDB) is a genetic lipoprotein disorder that can develop in patients homozygous for the APOE2 genotype ({varepsilon}2/{varepsilon}2). It is associated with decreased clearance of remnant lipoproteins and increased atherosclerotic cardiovascular disease (ASCVD) risk disproportionate to their level of LDL-C. A goal of this study was to develop a screening test for the {varepsilon}2/{varepsilon}2 genotype based on routinely available lipid tests and to determine those at most risk for ASCVD. MethodsAfter assembly of a primary prevention cohort from the UK Biobank (n= 269,895), gene array and exome data was utilized to classify patients as being {varepsilon}2/{varepsilon}2 genotype positive or negative. Lipid profiles and APOB levels were extracted and the number of ASCVD events was tabulated during a 15-year follow-up period. ResultsUsing a newly developed equation for estimating APOB (eAPOB) with lipid panel test results, the ratio of measured APOB to eAPOB was better than any other individual lipid test or ratio for identifying patients with the {varepsilon}2/{varepsilon}2 genotype (AUC: APOB/eAPOB: 0.990 (0.986-0.994), nonHDL-C/APOB: 0.961 (0.952-0.970), APOB: 0.955 (0.949-0.961), VLDL/TG: 0.788 (0.771-0.804)). The majority of {varepsilon}2/{varepsilon}2 patients could be identified with the APOB/eAPOB ratio even before they expressed the FDB phenotype with elevated TG and nonHDL-C. The PCE or PREVENT risk equations were the most accurate method for identifying higher risk patients (AUC: PREVENT: 0.690 (0.637-0.742), PCE: 0.697 (0.645-0.749)). ConclusionThe APOB/eAPOB ratio can be used to accurately identify the {varepsilon}2/{varepsilon}2 genotype and conventional risk equations are the best method for determining those at risk for ASCVD.

BACKGROUNDAbdominal aortic aneurysm (AAA) is a life-threatening condition with >80% mortality upon rupture and no effective pharmacotherapy available. Despite epidemiological evidence linking metformin use to reduced AAA progression, its mechanism remains elusive. Notably, peroxisome proliferator-activated receptor {gamma} coactivator 1 (PGC-1, encoded by Ppargc1a) is downregulated in human AAA, yet its functional role in metformins protection is unknown. METHODSWe employed porcine pancreatic elastase (PPE)-induced murine AAA, VSMC-specific Ppargc1a knockout (Ppargc1aVSMC-KO), primary VSMC senescence models, and pharmacological inhibition (Compound C for AMPK; Ex-527 for SIRT1) to define the AMPK-SIRT1-PGC-1 axis. RESULTSMetformin significantly inhibited AAA expansion, suppressed VSMC senescence (p53/p21{downarrow}, SA-{beta}-gal{downarrow}), and preserved contractile phenotype (SMTN{uparrow}, IL-6/TNF-{downarrow}). Crucially, all benefits were abrogated in Ppargc1aVSMC-KO mice, which exhibited accelerated aneurysm growth, mitochondrial fragmentation, ATP depletion, and ROS accumulation. Mechanistically, metformin activated AMPK/SIRT1 to upregulate PGC-1; AMPK or SIRT1 inhibition blocked this cascade and reversed protection. CONCLUSIONMetformin restrains AAA by restoring VSMC mitochondrial homeostasis via the AMPK/SIRT1[-&gt;]PGC-1 axis, positioning PGC-1 as a non-redundant, cell-autonomous guardian against vascular degeneration. These findings provide a mechanistic foundation for repurposing metformin and developing PGC-1-targeted therapies in AAA.

Introduction: Accurate stratification of hard atherosclerotic cardiovascular disease (ASCVD) risk remains challenging despite advances in prevention. Liver function biomarkers (LFBs), particularly gamma - glutamyl transferase (GGT), have been linked to cardiovascular outcomes, yet their contribution to hard ASCVD risk prediction is not well defined. Methods: This study analyzed data from the National Health and Nutrition Examination Survey (NHANES, 2005 - 2018) to assess cross - sectional associations between LFBs and 10 - year hard ASCVD risk estimated by the ACC/AHA Pooled Cohort Equations. Multivariable regression, restricted cubic splines, and mediation analyses were applied to examine independent and dose - response relationships. External validation was performed in the China Health and Retirement Longitudinal Study (CHARLS) and NHANES using machine learning models (CoxBoost, Naive Bayes and Random Forest). Results: Among 5,731 NHANES participants, GGT showed an independent linear association with hard ASCVD risk (P - trend = 0.003), partly mediated by systolic blood pressure (44.8%), HbA1c (19.0%), and high density lipoprotein cholesterol (13.4%). Machine learning (ML) models incorporating GGT, alkaline phosphatase (ALP), and globulin alongside traditional risk factors improved predictive accuracy, with Naive Bayes achieving an AUC of 0.751 in NHANES validation. Conclusions: GGT is an independent and biologically plausible biomarker of hard ASCVD risk, acting through cardiometabolic pathways. Incorporating LFBs into risk prediction models, particularly with machine learning, enhances risk stratification and may facilitate early identification of high - risk individuals.

Atherosclerosis is linked to an increased risk of cognitive decline, with chronic inflammation being a common feature of both pathologies. IL-12 activates STAT4 to regulate myeloid cell functions, and blockade of this pathway alleviates cognitive impairment in Alzheimers models. However, the mechanisms connecting vascular pathology to neuroinflammation remain unclear. Here, we examine whether STAT4 functions as a common mediator of neuroinflammation in atherosclerosis. We demonstrate that LysMCre-specific STAT4 deficiency ameliorates deficits in long-term memory in low-density lipoprotein-deficient (Ldlr-/-) mice fed a high-fat diet (HFD-C). STAT4 deficiency moderately reduces Ser199-phosphorylated Tau burden. Atherosclerosis alters brain immune composition, characterized by increased numbers of CD45+ leukocytes, activated microglia, and activated T and B cells, whereas STAT4 deficiency attenuates these effects. Nanostring gene-expression pathway analysis further highlights the importance of STAT4 in regulating multiple neuroinflammatory pathways and the Rhodopsin-like receptor signaling, which is associated with synaptic plasticity. LysMCre-specific STAT4 deficiency supports microglial efferocytosis in atherosclerotic Ldlr-/- mice and increases the number of efferocytotic macrophages. Accordingly, STAT4 deficiency also reduced neuronal death. Overall, our data reveal an important role for myeloid-driven STAT4 expression in the pathogenesis of cognitive decline associated with atherosclerosis, mediated through impaired efferocytosis and enhanced leukocyte activation, leading to increased brain neuroinflammation.

BACKGROUNDInactivation of ANGPTL3 (angiopoietin-like protein 3, A3) is a proven therapeutic strategy for lowering plasma lipid levels independently of the LDL receptor (LDLR), yet the optimal approach to inactivate A3 remains unclear. A3 is proteolytically cleaved and circulates as full-length (A3-FL), N-terminal (A3-Nter) and C-terminal (A3-Cter) fragments. The specific contribution of each form of A3, and of its paralog, ANGPTL8 (A8), in modulating circulating levels of ApoB-Containing Lipoproteins (ABCLs) remain poorly defined. Clarifying these relationships will inform next-generation A3-directed therapies. METHODSWe performed liver perfusion studies to directly compare the number and composition of VLDL particles secreted from mice with and without A3. To amplify effects on cholesterol metabolism, we generated Ldlr-/- mice expressing wildtype A3 (A3-WT), A3-FL or A3-Nter, with or without co-expression of A8, and analyzed plasma lipids, circulating A3 and A8 complexes, and intravascular lipase activities. Complementary in vitro assays and structural modeling were used to assess relative endothelial lipase (EL) inhibition by A3 alone or in complex with A8. RESULTSLiver perfusion studies revealed that A3 inactivation does not alter the rates of hepatic secretion of VLDL in wildtype or Ldlr-/- mice. Inactivation of A8 alone lowered plasma LDL-cholesterol (C) levels by [~]20%, an effect dependent upon the expression of both EL and A3. Maximal inhibition of lipoprotein lipase (LPL) required co-expression of A8 plus both A3-FL and A3-Nter, indicating that A3 cleavage, in addition to A8 expression, is essential for maximal LPL inhibition. In contrast, A8 expression, but not A3 cleavage, was required for optimal EL inhibition. CONCLUSIONSA8 acts in concert with A3 to differentially modulate LPL- and EL-mediated lipolysis, which antagonizes hepatic clearance of newly-secreted atherogenic ABCLs. This mechanistic framework refines our understanding of A3-targeted lipid lowering and highlights the therapeutic potential of dual A3- plus A8-directed strategies to treat dyslipidemia and prevent atherosclerotic cardiovascular disease. Clinical perspectiveO_ST_ABSWhat is new?C_ST_ABSO_LIInactivation of A3 lowers circulating ABCL levels without altering hepatic secretion rates of VLDL-ApoB or -TG. C_LIO_LIProteolytic cleavage of A3 is required for maximal inhibition of LPL. C_LIO_LIInactivation of A8 lowers LDL-C levels through an A3- and EL-dependent, but LDLR-independent, mechanism. C_LI What are the clinical implications?O_LICombining A8 inhibition with A3-inactivating therapies offers a strategy to achieve greater reduction in LDL-C levels and atherosclerotic cardiovascular risk. C_LI

BackgroundMyeloid cells orchestrate vascular inflammation through transcriptional programs that regulate their maturation, effector function, and survival. While lineage-determining transcription factors establish myeloid identity, understanding of the transcriptional regulation of myeloid behavior in chronic inflammatory contexts remains limited. Nuclear factor-Y (NF-Y) is a trimeric CCAAT-binding transcription factor that regulates cell proliferation and differentiation. Here, we investigate the role of NF-Y in myeloid function and survival during chronic vascular inflammation. MethodsIntegrated single-cell transcriptomics of BM, blood, and atherosclerotic lesions were combined with myeloid-specific NF-YA inactivation to define NF-Y-dependent transcriptional states. Functional consequences were assessed in mice with myeloid-specific Nfya deletion on a hypercholesterolemic Apoe-/- background using models of diet-induced advanced atherosclerosis and endoluminal femoral injury. Myeloid cell recruitment, survival, apoptosis, and proliferation were further examined in models of thioglycolate-induced peritonitis. ResultsNF-Y subunit transcripts were detected across myeloid compartments, with Nfya enriched in proliferative macrophages and immature neutrophils. In mouse atherosclerotic lesions, low Nfya expression was associated with lipid-handling and phagocytic macrophage signatures and a pro-inflammatory neutrophil phenotype. Myeloid Nfya deficiency was further associated with reduced circulating neutrophil counts, increased macrophage and neutrophil apoptosis during acute inflammation, expanded necrotic cores, larger unstable atherosclerotic lesions, and aggravated atherosclerosis and injury-induced neointimal thickening. ConclusionOur data identify NF-Y as a transcriptional safeguard of myeloid cell survival during inflammatory stress, thereby shaping disease progression and outcomes in vascular disease.

Background: Type 2 diabetes mellitus (T2DM) has long been considered a risk factor for cerebral small vessel disease (cSVD), yet the exact relationship between glycemic markers and cSVD remains unclear. This study explores the genetic overlap and causal associations between T2DM, glycemic indices, and cSVD phenotypes using genome-wide association studies (GWAS). Methods: Using large consortium-based GWAS data, we examined relationships between T2DM, glycemic indicators (glycated hemoglobin, fasting glucose, 2-hour glucose after oral challenge, and fasting insulin), and cSVD phenotypes (white matter hyperintensity volume, lacunar stroke, cerebral microbleeds, and enlarged perivascular spaces). Our multi-level genomic strategy included: 1) identifying pleiotropic single nucleotide polymorphisms (SNPs) through PLEIO and eQTL analysis, 2) assessing genome-wide genetic correlations using LDSC and GNOVA, and 3) determining causal relationships with two-sample and multivariable Mendelian randomization analyses. Results: We identified 14 pleiotropic SNPs with significant shared associations among T2DM, glycemic indicators, and cSVD phenotypes. Notably, MICB gene expression was elevated in brain, vascular, and pancreatic tissues, while three HLA genes (HLA-DQA1, HLA-DRB1 and HLA-DRB5) showed reduced expression. Genetic correlation analysis revealed positive correlations between T2DM, fasting glucose, and postprandial glucose with multiple cSVD phenotypes including WMH, lacunar stroke, and perivascular spaces. Mendelian randomization demonstrated that T2DM, 2-hour glucose, and HbA1c level causally increased lacunar stroke risk (OR 1.16 [1.09-1.23], OR 1.46 [1.20-1.77], OR 1.52 [1.04-2.23], respectively). Multivariable Mendelian randomization analysis confirmed that T2DM and postprandial glucose maintained a robust direct effect on lacunar stroke independent of other cSVD phenotypes, while HbA1c did not retain significance after conditioning on cSVD imaging markers. Conclusions: Our multi-level genomic analysis reveals links between T2DM, glycemic traits, and cSVD through specific genetic variants, genome-wide correlations, and causal relationships. The involvement of immune-related genes suggests potential biological mechanisms. The causal effect of postprandial glucose on lacunar stroke suggests that impaired glucose tolerance may be a relevant therapeutic target for lacunar stroke prevention.

STRUCTERED ABSTRACTO_ST_ABSBACKGROUNDC_ST_ABSCoronary artery bypass graft (CABG) is a widely performed procedure for coronary artery disease (CAD), yet its association with Impaired Cognition (IC), i.e., mild-cognitive impairment or all-cause dementia, while accounting for APO ({varepsilon}) genotype, remains unclear. METHODSWe analyzed AllofUS participants with CAD (Age[&ge;]60 yrs) from 2017-2023. We defined CAD as a history of angina/myocardial infarction/chronic ischemic heart disease or having percutaneous coronary intervention/CABG, and IC as mild cognitive impairment or all-cause dementia using ICD/SNOMED codes. We performed logistic regression analyses to assess the association between CABG and IC, adjusting for clinical factors (age, sex, hypertension, diabetes, hyperlipidemia, depression, stroke, smoking, alcohol use, statin/antihypertensive/antidiabetic use), social determinants (self-reported race/ethnicity, income, employment), and APO ({varepsilon}) genotypes. We further performed stratified analyses across APO ({varepsilon}) genotypes ({varepsilon}2/{varepsilon}2, {varepsilon}2/{varepsilon}3 {varepsilon}3/{varepsilon}3, {varepsilon}2/{varepsilon}4, {varepsilon}3/{varepsilon}4, {varepsilon}4/{varepsilon}4). We defined significance at p [&le;] 0.05. RESULTSWe included 22,349 with CAD and identified 908 with IC after CAD till 2023. 40% were females, 70% were White, 12% were Black, and 9% were Hispanic. The proportion of IC was higher (5.1% vs 3.5%, p=1e-08) in CABG (n=8,135) vs non-CABG (n=14,214). After adjusting for clinical factors, social determinants, and APO ({varepsilon}) genotypes, CABG (1.23;1.06-1.41, p = 0.005) was associated with IC. In APO ({varepsilon}) stratified analysis, the association of CABG with IC was strongest in the APO {varepsilon}2/{varepsilon}3 group (1.91;1.21-3.02, p = 0.005). CONCLUSIONIn the AllofUS cohort, we observed an association between CABG and IC in CAD participants, with the strongest association in the APO {varepsilon}2/{varepsilon}3 group. Key MessageO_ST_ABSWhat is already known on this topicC_ST_ABSCoronary artery disease (CAD) and Impaired Cognitive (IC) disease, i.e., mild cognitive impairment and all-cause dementia, share genetic, sociodemographic, and clinical factors, including cardiovascular conditions like coronary artery bypass grafting (CABG) procedure. What this study addsWe observed an association between CABG and IC in CAD participants after adjusting for sociodemographic, clinical factors, and APO ({varepsilon}) effects. Further, when CAD participants were stratified across APO ({varepsilon}) groups, CABG was significantly associated with IC in the APO {varepsilon}2/{varepsilon}3 group. How this study might affect research, practice or policyOur observations highlight the role of APO ({varepsilon}) genotype evaluation in CAD patients for IC risk assessment.

Background: Familial hypercholesterolemia (FH) is most frequently caused by pathogenic variants in LDLR, but phenotypic variability suggests the influence of genetic modifiers. Methods: We investigated a large multigenerational family with FH, combining clinical data, lipid profiles, and genetic analysis with functional studies. LDLR and PCSK9 variants were characterized according to ACMG/ClinGen guidelines. Functional assays in CHO-ldlA7 cells assessed LDLR activity, while plasma PCSK9 levels were quantified by ELISA. Results: LDLR c.2479G>A variant was associated with FH in the family. The presence of loss of function c.137G>T and c.2023del variants at PCSK9 appears to mitigate the effect of the LDLR variant. Conclusions: This study provides evidence that PCSK9 variants can counteract the deletereous effect of a LDLR variant associated with FH. These findings highlight the importance of gene/gene interactions in the clinical variability of FH and their potential implications for precision medicine.

BackgroundSex-related differences in cardiovascular disease suggest the presence of intrinsic vasoprotective mechanisms, with estrogen recognized as an important modulator of endothelial function. Building on existing evidence, the present study provides mechanistic insights into how estrogen and nitric oxide (NO) signaling regulate selective pathways of oxLDL uptake, mitochondrial dynamics, and inflammatory responses during early atherogenesis. MethodsWe combined an in vitro endothelial cell-macrophage co-culture model with in vivo studies in low-density lipoprotein receptor-knockout (LDLr-/-) mice to investigate the role of estrogen in early atherosclerotic processes. Human aortic endothelial cells (HAECs) were exposed to oxidized low-density lipoprotein (oxLDL) in the presence or absence of 17{beta}-estradiol (E2) and the nitric oxide (NO*) donor S-nitroso-N-acetylcysteine (SNAC). Key outcomes included oxLDL uptake, mitochondrial oxidative stress, mitochondrial dynamics, and inflammatory signaling. In vivo, male and female LDLr-/- mice were exposed to a short-term high-fat diet with or without SNAC treatment. Plasma lipid levels, blood pressure, aortic lesion formation, and cardiac remodeling were evaluated. ResultsE2 reduced oxLDL uptake and oxidative stress, effects recapitulated by SNAC; however, these responses involved distinct entry pathways, with E2 preferentially modulating lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) dependent uptake and SNAC targeting caveolae-associated mechanisms. In parallel, both E2 and SNAC reduced Scavenger Receptor Class B Type 1 (SR-B1) expression, suggesting an additional modulation on oxLDL transcytosis via this mechanism. Endothelial cells exposed to oxLDL exhibited altered mitochondrial regulatory proteins, including superoxide dismutase 2 (SOD-2), dynamin-related protein 1 (Drp-1), and optic atrophy protein 1 (OPA-1). Despite reducing oxidative stress, E2 increased the expression of adhesion molecules and enhanced monocyte adhesion in response to oxLDL exposure, particularly when combined with SNAC. Strikingly, E2 also modulated macrophage responses, increasing interleukin receptor antagonist (IL-1ra) expression and reducing GDF15, macrophage inhibitory factor (MIF), macrophage inflammatory protein 3 alfa (MIP-3), and matrix metalloproteinase 9 (MMP-9) levels, consistent with a less pro-inflammatory macrophage profile. In vivo, HFD increased plasma lipid levels and atherosclerotic lesion area in LDLr-/- mice, whereas SNAC partially attenuated these effects without affecting plasma lipid levels. In vivo, female LDLr-/- mice developed approximately 50% smaller aortic lesions than males, despite comparable or higher plasma lipid levels. A dyslipidemia led to increased blood pressure and a hypertensive phenotype in both males and females. SNAC treatment reduced lesion burden in both sexes and prevented diet-induced hypertension in females. ConclusionEstrogen limits early atherogenic injury by reducing endothelial uptake of oxLDL, preserving mitochondrial homeostasis, and modulating inflammatory signaling. Together, the E2 and NO pathways regulate early atherosclerosis through distinct yet complementary mechanisms, offering a potential framework for vascular-protective strategies.

Background: Unruptured intracranial aneurysms (UIAs) pose a significant risk of subarachnoid hemorrhage. Both hypertension and hyperhomocysteinemia are recognized as independent risk factors for vascular disease; however, their combined impact (H-type hypertension) on aneurysm instability and rupture remains unclear. Methods: We analyzed a prospective cohort of 358 adults with UIAs (475 aneurysms) using high-resolution vessel-wall MRI (HRVWI) for cross-sectional and longitudinal assessment. H-type hypertension was defined as hypertension with plasma homocysteine ?10 ?mol/L. Multivariable logistic regression assessed associations with AWE and aneurysm growth (longitudinal sub-cohort: n = 82, 89 aneurysms). Mendelian randomization (MR) analyses evaluated the causal role of homocysteine in hypertension and aSAH. Proteomic profiling identified potential molecular mechanisms. Results: AWE occurred in 33.7% of aneurysms, which were larger, irregular, and had higher PHASES scores. Elevated homocysteine (10.3 vs 9.5 ?mol/L, p = 0.004) and H-type hypertension (43.8% vs 28.3%, p < 0.001) were associated with AWE. After adjustment, H-type hypertension independently predicted AWE (OR = 3.18) and aneurysm growth (OR = 3.63). MR analyses showed homocysteine increased aSAH (OR = 1.39) and hypertension risk (OR = 1.10), while hypertension increased aSAH risk (OR = 1.58). Mediation analysis did not support hypertension as a mediator (p = 0.20). Proteomic analyses identified key pathways related to inflammation?immune dysregulation, extracellular matrix remodeling, and signaling activation as potential mediators. Conclusions: H-type hypertension amplifies aneurysmal-wall instability and growth. Combined control of blood pressure and homocysteine merits prospective evaluation for UIA prevention.

BackgroundAtherosclerosis is the primary underlying cause of coronary artery disease (CAD). Leiomodin1 is a vascular smooth muscle cell (VSMC)-restricted CAD risk gene whose role in coronary artery pathophysiology is unknown. Global loss of Leiomodin1 causes lethal neonatal visceral myopathy, requiring unique approaches for study in VSMCs. MethodsSeveral distinct Leiomodin1 mutant mouse models were generated by clustered regularly interspaced short palindromic repeats (CRISPR). Control (Lmod1WT) and VSMC-restricted Lmod1 knockout (Lmod1SMKO) mice were subjected to various atherogenic regimens. Atherosclerosis and LMOD1 expression in mouse and human coronary arteries were assessed by histopathology and confocal immunofluorescence microscopy. Coronary arteries from Lmod1WT and Lmod1SMKO mice were analyzed with assorted stains and antibodies, immunogold lineage tracing, spatial metabolomics/transcriptomics, and single-cell RNA sequencing (scRNA-seq). Mouse aortic SMCs from Lmod1WT and Lmod1SMKO mice were subjected to lipid loading with lentiviruses expressing wild-type Lmod1, a nucleation deficient Leiomodin1 (Lmod1ND), or a short hairpin RNA (shRNA) targeting Thrombospondin (Thbs1). ResultsUnder atherogenic conditions, Lmod1SMKO mice displayed unremarkable vessels in several organs but developed diffuse and occlusive coronary atherosclerosis. No such disease was observed in Lmod1WT mice. Time-course studies documented lipid insudation and VSMC foam cell formation in the coronary arteries of Lmod1SMKO mice as early as six days post-regimen. Immunogold lineage tracing demonstrated 46% of coronary plaque cells being of VSMC origin, with most showing evidence of lipid uptake. An intronic deletion of Lmod1, containing a conserved region where the single nucleotide variant associated with CAD exists, showed attenuated LMOD1 expression; heterozygous Lmod1SMKO mice, with a similar reduction in LMOD1, showed no CAD. Spatial metabolomics uncovered multiple lipid species within coronary atheromata of Lmod1SMKO mice, and spatial/scRNA-seq of similar coronary lesions disclosed altered lipid pathways with a consistent elevation in Thbs1. In vitro mechanistic studies revealed lipid accumulation in Lmod1SMKO VSMCs that was rescued by Lmod1WT, Lmod1ND, and Thbs1 shRNA. VSMC-restricted expression of Lmod1ND in mice resulted in negligible coronary atherosclerosis. ConclusionsUnder proatherogenic conditions, Lmod1SMKO mice present with rapidly manifesting coronary atherosclerosis that appears to be independent of the actin nucleation function of LMOD1. Targeting Thbs1 represents a viable strategy to mitigate VSMC foam cell formation. Clinical PerspectiveO_ST_ABSWhat is new?C_ST_ABSO_LIVascular smooth muscle cell (VSMC) loss of Leiomodin1 (Lmod1) causes diffuse and occlusive coronary atherosclerosis in mice, with little or no such disease in other vascular beds. C_LIO_LIA novel immunogold lineage tracing assay shows VSMC migration to the intima as early as six days following an atherogenic regimen, and quantitative studies demonstrate that 46% of coronary plaque cells are of SMC origin. C_LIO_LIThe coronary phenotype appears to be independent of LMOD1s actin nucleation activity, but VSMC lipid uptake is thrombospondin-dependent. C_LI What are the clinical implications?O_LILMOD1 is an annotated smooth muscle cell-restricted risk allele for human coronary artery disease (CAD), offering new insight into the role of smooth muscle cells in atherogenesis. C_LIO_LIThe rapidly manifesting CAD phenotype in Lmod1 knockout mice enables expedited testing of novel therapeutics to mitigate disease progression. C_LIO_LINew insight into LMOD1 pathobiology will help inform further SNV interrogation of the LMOD1 locus for CAD risk in patients. C_LI

DOT1L-catalyzed H3K79 methylation is a hallmark of actively transcribed genes and has been extensively studied in developmental and disease contexts. While DOT1L inhibition has emerged as a promising therapeutic strategy in cancer, its role in pro-atherogenic endothelial inflammation remains unclear. To investigate this, we utilized an in vivo partial carotid artery ligation model and observed increased DOT1L expression and H3K79me3 level. Consistently, in vitro studies employing a 3D-printed human coronary artery model and TNF- stimulation corroborated these results, showing elevated DOT1L expression and H3K79me3 deposition, while levels of H3K79me and me2 remained unchanged. Further analyses identified key DOT1L-containing complex (DotCom) components, AF10 and AF9 (upregulated) and AF17 (downregulated), as contributors to the enhanced H3K79me3 landscape. CUT&RUN sequencing showed prominent H3K79me3 enrichment at the RELA (NF-{kappa}B p65) promoter, corresponding with increased NF-{kappa}B p65 expression and activation. Notably, inhibition/knockdown of the methyltransferase DOT1L or overexpression of the demethylase FBXL10 significantly reduced H3K79me3 levels, thereby suppressing NF-{kappa}B p65 expression and attenuating endothelial inflammation, independent of canonical NF-{kappa}B p65 activation. These findings establish DOT1L-mediated H3K79me3 as a crucial epigenetic regulator of endothelial inflammation, highlighting a potential therapeutic avenue for mitigating NF-{kappa}B p65-driven pro-atherogenic endothelial dysfunction.