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Schunkert, H.

Publications and source records attributed to Schunkert, H..

17 recordsLinked to original sources

Intraindividual longitudinal changes of the proteome reveal dynamic markers of biological aging

Proteomic aging clocks have emerged as biomarkers of aging, but most rely on cross-sectional data. Here, we present a proteomic aging clock based on longitudinal measurements of liquid chromatography-mass spectrometry plasma proteomics at up to three time points in the population-based KORA cohort, comprising 9,105 samples from 4,100 individuals in the final dataset aged 25-88 years. The model predicts chronological age and yields a measure of proteomic age acceleration associated with lifestyle and clinical risk factors. Risk factor-stratified analyses reveal shared proteomic signatures among cardiometabolic exposures and distinct signatures for smoking and physical activity. Within individuals, dyslipidemia and impaired kidney function track transitions to increases in age acceleration, while higher age acceleration is associated with increased all-cause mortality. Mediation analysis suggests that risk factors are linked to mortality indirectly through age acceleration. Affected proteins and pathways highlight extracellular matrix remodeling, complement and coagulation pathways, and liver-derived plasma proteins as key contributors to aging. Mendelian randomization identifies proteins with evidence consistent with a causal role in aging-related traits. Together, these findings are consistent with biological aging being dynamically responsive to changes in modifiable risk factors.

bioinformatics↗

Antibody-mediated inhibition of ADAMTS-7 reduces experimental atherosclerosis

Objective: One of the strongest genetic associations with coronary artery disease (CAD) risk maps to the metalloproteinase 'a disintegrin and metalloproteinase with thrombospondin motifs 7' (ADAMTS-7) locus. The protein was shown to promote plaque formation and instability. We aimed to generate and evaluate an antibody-based strategy targeting ADAMTS-7 therapeutically to reduce atherosclerotic plaque formation. Approach and Results: A truncated form of human ADAMTS-7 was produced in Nicotiana benthamiana and used as antigen for antibody generation by hybridoma technology. Eight monoclonal antibodies (mAbs) were screened, among which ADAMTS-7-mAb32 (mAb32) demonstrated the highest affinity, as confirmed by surface plasmon resonance analyses and immunoblotting against full-length ADAMTS-7. In vitro, mAb32 inhibited interactions of ADAMTS-7 with its substrates TIMP-1 and SVEP1 in a dose- and time-dependent manner, as assessed by time-resolved Forster resonance energy transfer assays. To assess therapeutic efficacy in vivo, Apoe-/- mice were fed a Western diet for ten weeks and treated with weekly injections of mAb32 or control IgG over the last six weeks. En face aortic Oil Red O staining revealed significantly reduced plaque area in the treatment group, without changes in plasma cholesterol levels or body weight. No evidence of liver or kidney toxicity was observed. Conclusion: Monoclonal antibody-based inhibition of ADAMTS-7 reduced atherosclerotic burden in vivo without affecting lipid metabolism, supporting ADAMTS-7 as a viable therapeutic target in CAD. Further development of mAb32 may provide a cholesterol-independent treatment strategy for atherosclerosis.

physiology↗

A cell type-resolved proteomic atlas of the human body

Proteins define what cells do, yet their systematic quantification across human cell types has remained out of reach. Using Deep Visual Proteomics on tissue from a healthy female donor, we built an atlas of 27 cell types across 14 tissues, quantifying two-thirds of all human protein-coding genes, with up to 8,500 per population. The proteome partitions bimodally into a universal core and highly specialized programs. Integration into the Human Protein Atlas Single Cell Resource enabled comparison of RNA and protein abundance at cell type resolution, revealing that concordance depends on pathway rather than cellular identity. This resolution uncovered cancer-testis antigens in oocytes invisible to bulk profiling. Our openly accessible resource provides a foundation for cell type-resolved proteomics in health and disease.

biochemistry↗

Cancer drives atherosclerotic plaque vulnerability by inducing pathological angiogenesis

Cardiovascular disease (CVD) is the leading cause of death for many cancer survivors, a phenomenon traditionally attributed to shared risk factors and cardiotoxic chemotherapies. Here, we hypothesized that cancer may also directly promote atherosclerosis. Propensity-matched analyses confirmed significantly elevated cardiovascular event rates amongst cancer patients, independent of comorbidities such as smoking. Atheroprone mice implanted with colorectal tumors demonstrated accelerated features of plaque vulnerability, driven by pathological angiogenesis and intraplaque hemorrhage. Mechanistically, tumor-secreted TNF- induced the pro-angiogenic factor LRG1 across multiple murine models and human plaques. Therapeutic interventions targeting these pathways, including with FDA-approved cytokine inhibitors or tumor resection, prevented plaque destabilization in mice and reduced coronary revascularization rates in patients. Together, these findings suggest that cancer may causally promote CVD and unveil novel translational strategies for cancer survivors.

pathology↗

Cigarette smoking upregulates vascular expression of the novel atherosclerosis risk factor ADAMTS-7

BackgroundCigarette smoking is an established risk factor for coronary artery disease (CAD) and myocardial infarction. Genetic variants in the extracellular matrix protease ADAMTS-7 were also identified to increase CAD risk. Notably, ADAMTS7 represents the only genomic locus that revealed a gene-environment interaction with smoking. The underlying mechanisms of this interaction remain unclear. Methods and ResultsIn a murine model, cigarette smoke exposure (CSE) led to an upregulation of vascular ADAMTS7 expression in wild type (WT) C57BL/6J mice. ADAMTS7 upregulation was also found in carotid plaques from ever-smokers undergoing carotid endarterectomy in humans. Bulk RNA sequencing of lung tissues from WT mice exposed to CS revealed a downregulation of 20 and an upregulation of 173 transcripts. Among upregulated transcripts in smoking-exposed lungs, we found C-C motif chemokine ligand 17 (CCL17), which was likewise upregulated in plasma from smoking mice and humans. In vitro, recombinant CCL17 upregulated ADAMTS7 expression in primary vascular smooth muscle cells (VSMC), which was inhibited secondary to silencing of CCL17s bona fide receptor C-C Motif Chemokine Receptor 4 (CCR4). Conditioned media from CCL17-stimulated VSMC lacking ADAMTS-7 showed reduced release of inflammatory cytokines by endothelial cells (EC), reduced EC activation, and monocyte-to-EC adhesion. In proatherogenic Apoe-/- mice exposed to CS, more numerous neutrophils, inflammatory monocytes, and macrophages were found in atherosclerotic plaques as compared to room air exposition. This effect was blunted in Apoe-/-Adamts7-/- mice. ConclusionsFor the first time, our findings link CSE to vascular inflammation via CCL17-mediated upregulation of the CAD risk factor ADAMTS7 and provide a mechanistic explanation for the gene-environment interaction between CS and ADAMTS7 in CAD. Targeting ADAMTS-7 might be a promising therapeutic strategy irrespective of smoking status. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=85 SRC="FIGDIR/small/685237v1_ufig1.gif" ALT="Figure 1"> View larger version (16K): org.highwire.dtl.DTLVardef@1d8366eorg.highwire.dtl.DTLVardef@1dda3feorg.highwire.dtl.DTLVardef@39a4bcorg.highwire.dtl.DTLVardef@6e58b6_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

Cell type-specific epigenetic regulatory circuitry of coronary artery disease loci

Coronary artery disease (CAD) is the leading cause of death worldwide. Recently, hundreds of genomic loci have been shown to increase CAD risk, however, the molecular mechanisms underlying signals from CAD risk loci remain largely unclear. We sought to pinpoint the candidate causal coding and non-coding genes of CAD risk loci in a cell type-specific fashion. We integrated the latest statistics of CAD genetics from over one million individuals with epigenetic data from 45 relevant cell types to identify genes whose regulation is affected by CAD-associated single nucleotide variants (SNVs) via epigenetic mechanisms. Applying two statistical approaches, we identified 1,580 genes likely involved in CAD, about half of which have not been associated with the disease so far. Enrichment analysis and phenome-wide association studies linked the novel candidate genes to disease-specific pathways and CAD risk factors, corroborating their disease relevance. We showed that CAD-SNVs are enriched to regulate gene expression by affecting the binding of transcription factors (TFs) with cellular specificity. Of all the candidate genes, 23.5% represented non-coding RNAs (ncRNA), which likewise showed strong cell type specificity. We conducted a proof-of-concept biological validation for the novel CAD ncRNA gene IQCH-AS1. CRISPR/Cas9-based gene knockout of IQCH-AS1, in a human preadipocyte strain, resulted in reduced preadipocyte proliferation, less adipocyte lipid accumulation, and atherogenic cytokine profile. The cellular data are in line with the reduction of IQCH-AS1 in adipose tissues of CAD patients and the negative impact of risk alleles on its expression, suggesting IQCH-AS1 to be protective for CAD. Our study not only pinpoints CAD candidate genes in a cell type-specific fashion but also spotlights the roles of the understudied ncRNA genes in CAD genetics.

bioinformatics↗

Polygenic Risk Score Associates with Atherosclerotic Plaque Characteristics at Autopsy

BackgroundPolygenic risk scores (PRS) for coronary artery disease (CAD) potentially improve cardiovascular risk prediction. However, their relationship with histopathologic features of CAD has never been examined systematically. MethodsFrom 4,327 subjects referred to CVPath by the State of Maryland Office Chief Medical Examiner (OCME) for sudden death between 1994 and 2015, 2,455 cases were randomly selected for genotyping. We generated PRS from 291 known CAD risk loci. Detailed histopathologic examination of the coronary arteries was performed in all subjects. The primary study outcome measurements were histopathologic plaque features determining severity of atherosclerosis, including %stenosis, calcification, thin-cap fibroatheromas (TCFA), and thrombotic CAD. ResultsAfter exclusion of cases with insufficient DNA sample quality or with missing data, 954 cases (mean age 48.8{+/-}14.7; 75.7% men) remained in the final study cohort. Subjects in the highest PRS quintile exhibited more severe atherosclerosis compared to subjects in the lowest quintile, with greater %stenosis (80.3%{+/-}27.0% vs. 50.4%{+/-}38.7%; adjusted p<0.001) and a higher frequency of calcification (69.6% vs. 35.8%; adjusted p=0.004) and TCFAs (26.7% vs. 9.5%; adjusted p=0.007). Even after adjustment for traditional CAD risk factors subjects within the highest PRS quintile had higher odds of severe atherosclerosis (i.e., [&ge;]75% stenosis; adjusted OR 3.77; 95%CI 2.10-6.78; p<0.001) and plaque rupture (adjusted OR 4.05; 95%CI 2.26-7.24; p<0.001). Moreover, subjects within the highest quintile had higher odds of CAD-associated cause of death, especially among those aged 50 years and younger (adjusted OR 4.08; 95%CI 2.01-8.30; p<0.001). No associations were observed with plaque erosion. ConclusionsThis is the first autopsy study investigating associations between PRS and atherosclerosis severity at the histopathologic level in subjects with sudden death. Our pathological analysis suggests PRS correlates with plaque burden and features of advanced atherosclerosis and may be useful as a method for CAD risk stratification, especially in younger subjects. HighlightsO_LIIn this autopsy study including 954 subjects within the CVPath Sudden Death Registry, high PRS correlated with plaque burden and atherosclerosis severity. C_LIO_LIThe PRS showed differential associations with plaque rupture and plaque erosion, suggesting different etiologies to these two causes of thrombotic CAD. C_LIO_LIPRS may be useful for risk stratification, particularly in the young. Further examination of individual risk loci and their association with plaque morphology may help understand molecular mechanisms of atherosclerosis, potentially revealing new therapy targets of CAD. C_LI Graphic AbstractA polygenic risk score, generated from 291 known CAD risk loci, was assessed in 954 subjects within the CVPath Sudden Death Registry. Histopathologic examination of the coronary arteries was performed in all subjects. Subjects in the highest PRS quintile exhibited more severe atherosclerosis as compared to subjects in the lowest quintile, with a greater plaque burden, more calcification, and a higher frequency of plaque rupture.

genetics↗

The novel coronary artery disease risk factor ADAMTS-7 modulates atherosclerotic plaque formation by degradation of TIMP-1

BackgroundThe ADAMTS7 locus was genome-wide significantly associated with coronary artery disease (CAD). Lack of the extracellular matrix (ECM) protease ADAMTS-7 was shown to reduce atherosclerotic plaque formation. ObjectiveTo identify molecular mechanisms and downstream targets of ADAMTS-7 mediating risk of atherosclerosis. MethodsTargets of ADAMTS-7 were identified by high-resolution mass spectrometry of atherosclerotic plaques from Apoe-/- and Apoe-/-Adamts7-/- mice. ECM proteins were identified using solubility profiling. Putative targets were validated using immunofluorescence, in vitro degradation assays, co-immunoprecipitation, and Forster resonance energy transfer (FRET)-based protein-protein interaction assays. ADAMTS7 expression was measured in fibrous caps of human carotid artery plaques. ResultsIn humans, ADAMTS7 expression was higher in caps of unstable as compared to stable carotid plaques. Compared to Apoe-/- mice, atherosclerotic aortas of Apoe-/- mice lacking Adamts-7 (Apoe-/-Adamts7-/-) contained higher protein levels of tissue inhibitor of metalloproteases 1 (Timp-1). In co-immunoprecipitation experiments, the catalytic domain of ADAMTS-7 bound to TIMP-1, which was degraded in the presence of ADAMTS-7 in vitro. ADAMTS-7 reduced the inhibitory capacity of TIMP-1 at its canonical target matrix metalloprotease 9 (MMP-9) As a downstream mechanism, we investigated collagen content in plaques of Apoe-/- and Apoe-/-Adamts7-/- mice after Western diet. Picrosirius red staining of the aortic root revealed less collagen as a readout of higher MMP-9 activity in Apoe-/- as compared to Apoe-/- Adamts7-/- mice. In order to facilitate high-throughput screening for ADAMTS-7 inhibitors with the aim to decrease TIMP-1 degradation, we designed a FRET-based assay targeting the ADAMTS-7 catalytic site. ConclusionADAMTS-7, which is induced in unstable atherosclerotic plaques, decreases TIMP-1 stability reducing its inhibitory effect on MMP-9, which is known to promote collagen degradation and is likewise genome-wide significantly associated with CAD. Disrupting the interaction of ADAMTS-7 and TIMP-1 might be a strategy to increase collagen content and plaque stability for reduction of atherosclerosis-related events.

molecular biology↗

Loss of soluble guanylyl cyclase in platelets contributes to atherosclerotic plaque formation and vascular inflammation

AimThe role of platelets in atherosclerosis remains incompletely understood. Variants in genes encoding the soluble guanylyl cyclase (sGC) in platelets are associated with coronary artery disease (CAD) risk. Here we sought to investigate the contribution of platelet sGC to atherosclerosis and the therapeutic potential of targeting sGC in atherosclerosis. Methods and ResultsWe genetically deleted sGC in platelets of atherosclerosis-prone Ldlr-/- mice. By intravital fluorescence microscopy such Pf4-Cre+Gucy1b1flox/floxLdlr-/- mice displayed enhanced leukocyte adhesion to atherosclerotic plaques in comparison with their litter mates. Moreover, histological and flow cytometry analyses revealed more numerous inflammatory leukocytes and larger plaque sizes in aortic tissue of Ldlr-/- mice lacking sGC in platelets. In vitro, supernatant from activated platelets lacking sGC promoted leukocyte adhesion to endothelial cells (EC) via enhanced EC activation. Using cytokine profiling, we identified reduced angiopoietin-1 release by Pf4-Cre+Gucy1b1flox/flox and human GUCY1A1 risk allele carrier platelets to be responsible for enhanced activation of EC and subsequent leukocyte adhesion. Pharmacological sGC stimulation increased platelet angiopoietin-1 release in vitro and reduced recruitment of adoptively transferred leukocytes in Ldlr-/- mice fed a Western diet. Pharmacological sGC stimulation further reduced atherosclerotic plaque formation and vascular inflammation. ConclusionLoss of sGC in platelets contributes to atherosclerotic plaque formation via reduced release of the soluble factor angiopoietin-1 and, subsequently, enhanced leukocyte recruitment. Pharmacological sGC stimulation might represent a novel therapeutic strategy to prevent and treat CAD. Translational perspectiveReduced platelet soluble guanylyl cyclase activity contributes to atherosclerotic plaque formation and vascular inflammation. Stimulators of the soluble guanylyl cyclase, an emerging class of drugs already used in pulmonary hypertension and heart failure, are able to reduce atherosclerosis and inflammation in this preclinical model. Together with evidence from human genetics, our findings suggest a promising role of soluble guanylyl cyclase stimulation to prevent coronary artery disease.

physiology↗

Deficiency of ZC3HC1 increases vascular smooth muscle cell migration, proliferation and neointima formation following injury

RationaleThe ZC3HC1 gene has been linked to various cardiovascular traits. One variant, rs11556924-T, has been found to lower the risk of coronary artery disease (CAD) and blood pressure but increases carotid intima-media thickness (IMT). ObjectiveThis study aimed to determine how ZC3HC1 affects IMT using in vitro and in vivo models. We analyzed the effect of the rs11556924-T allele on ZC3HC1 expression in vascular smooth muscle cells (SMCs) from 151 multi-ethnic heart transplant donors. The results showed that rs11556924-T was associated with lower ZC3HC1 expression and faster SMC migration. ZC3HC1 knockdown (KD) experiments supported these findings, showing increased migration and proliferation. Mechanistically ZC3HC1 KD led to decreased expression of contractile marker genes and the accumulation of cyclin B1, a key cell cycle protein. Pathway analysis of differentially expressed genes between ZC3HC1 KD and controls SMCs showed decreased expression of genes in the cell division and cytoskeleton organization pathways, as well as higher expression of genes involved in extracellular matrix organization and cytokine-mediated signaling. To validate these findings in vivo, we generated and characterized knockout (Zc3hc1-/-) mice. These mice had enhanced neointima formation in response to arterial injury and faster SMCs migration ability. However, complete loss of Zc3hc1 led to a significant reduction in SMC proliferation and lower cyclin B1 protein level. In addition, immunostaining and confocal microscopy demonstrated, for the first time, that ZC3HC1 and Cyclin B1 were located at the cleavage furrow during mitotic progression of SMCs. ConclusionsCollectively, our study suggests that lower ZC3HC1/NIPA level leads to increased SMC migration and neointima formation. Moreover, we proposed a biphasic role of NIPA in proliferation. Lower levels of NIPA promote SMC proliferation, while complete loss of NIPA hampers cell division and abrogates proliferation.

genetics↗

Transcriptome-wide association study of coronary artery disease identifies novel susceptibility genes

Transcriptome-wide association studies (TWAS) explore genetic variants affecting gene expression for association with a trait. Here we studied coronary artery disease (CAD) using this approach by first determining genotype-regulated expression levels in nine CAD relevant tissues by EpiXcan in two genetics-of-gene-expression panels, the Stockholm-Tartu Atherosclerosis Reverse Network Engineering Task (STARNET) and the Genotype-Tissue Expression (GTEx). Based on these data we next imputed gene expression in respective nine tissues from individual level genotype data on 37,997 CAD cases and 42,854 controls for a subsequent gene-trait association analysis. Transcriptome-wide significant association (P < 3.85e-6) was observed for 114 genes, which by genetic means were differentially expressed predominately in arterial, liver, and fat tissues. Of these, 96 resided within previously identified GWAS risk loci and 18 were novel (CAND1, EGFLAM, EZR, FAM114A1, FOCAD, GAS8, HOMER3, KPTN, MGP, NLRC4, RGS19, SDCCAG3, STX4, TSPAN11, TXNRD3, UFL1, WASF1, and WWP2). Gene set analyses showed that TWAS genes were strongly enriched in CAD-related pathways and risk traits. Associations with CAD or related traits were also observed for damaging mutations in 67 of these TWAS genes (11 novel) in whole-exome sequencing data of UK Biobank. Association studies in human genotype data of UK Biobank and expression-trait association statistics of atherosclerosis mouse models suggested that newly identified genes predominantly affect lipid metabolism, a classic risk factor for CAD. Finally, CRISPR/Cas9-based gene knockdown of RGS19 and KPTN in a human hepatocyte cell line resulted in reduced secretion of APOB100 and lipids in the cell culture medium. Taken together, our TWAS approach was able to i) prioritize genes at known GWAS risk loci and ii) identify novel genes which are associated with CAD.

genetics↗

Heterozygous ATP-binding Cassette Transporter G5 Gene Deficiency and Risk of Coronary Artery Disease

BackgroundFamilial sitosterolemia is a rare, recessive Mendelian disorder characterized by hyperabsorption and decreased biliary excretion of dietary sterols. Affected individuals typically have complete genetic deficiency - homozygous loss-of-function (LoF) variants -- in the ATP-binding cassette transporter G5 (ABCG5) or G8 (ABCG8) genes, and have substantially elevated plasma sitosterol and low-density lipoprotein cholesterol (LDL-C) levels. The impact of partial genetic deficiency of ABCG5 or ABCG8, as occurs in heterozygous carriers of LoF variants, on LDL-C and risk of coronary artery disease (CAD) has remained uncertain.\n\nMethodsWe first recruited nine sitosterolemia families, identified causative LoF variants in ABCG5 or ABCG8, and evaluated the associations of these ABCG5 or ABCG8 LoF variants with plasma phytosterols and lipid levels. We next assessed for LoF variants in ABCG5 or ABCG8 in CAD cases (n=29,361) versus controls (n=357,326). We tested the association of rare LoF variants in ABCG5 or ABCG8 with blood lipids and risk for CAD. Rare LoF variants were defined as protein-truncating variants with minor allele frequency less than 0.1% in ABCG5 or ABCG8.\n\nResultsIn sitosterolemia families, seven pedigrees harbored causative LoF variants in ABCG5 and two pedigrees in ABCG8. Homozygous LoF variants in either ABCG5 or ABCG8 led to marked elevations in sitosterol and LDL-C. Of those sitosterolemia families, heterozygous carriers of ABCG5 LoF variants exhibited increased sitosterol and LDL-C levels compared to non-carriers. Within the large-scale CAD case-control cohorts, prevalence of rare LoF variants in ABCG5 and in ABCG8 were approximately 0.1% each. ABCG5 heterozygous LoF variant carriers had significantly elevated LDL-C levels (24.7 mg/dL; 95% confidence interval [CI] 14 to 35; P=1.1x10-6), and were at two-fold increased risk of CAD (odds ratio 2.06, 95% CI 1.27 to 3.35; P=0.004). By contrast, ABCG8 heterozygous LoF carrier status was not associated with increased LDL-C or risk of CAD.\n\nConclusionsAlthough familial sitosterolemia is traditionally considered as a recessive disorder, we observed that heterozygous carriers of a LoF variant in ABCG5 had significantly increased sitosterol and LDL-C levels and a two-fold increase in risk of CAD.

genetics↗

KCND3 is a novel susceptibility locus for early repolarization

The presence of an early repolarization pattern (ERP) on the surface electrocardiogram (ECG) is associated with risk of ventricular fibrillation and sudden cardiac death. Family studies have shown that ERP is a highly heritable trait but molecular genetic determinants are unknown. We assessed the ERP in 12-lead ECGs of 39,456 individuals and conducted a two-stage meta-analysis of genome-wide association studies (GWAS). In the discovery phase, we included 2,181 cases and 23,641 controls from eight European ancestry studies and identified 19 genome-wide significant (p<5E-8) variants in the KCND3 (potassium voltage gated channel subfamily D member 3) gene with a p-value of 4.6E-10. Replication of two loci in four additional studies including 1,124 cases and 12,510 controls confirmed the association at the KCND3 gene locus with a pooled odds ratio of 0.82, p=7.7E-12 (rs1545300 minor allele T). A subsequent GWAS meta-analysis combining all samples did not reveal additional loci. The lead SNP of the discovery stage (rs12090194) was in strong linkage disequilibrium with rs1545300 (r2=0.96, D=1). Summary statistics based conditional analysis did not reveal any secondary signals. Co-localization analyses indicate causal effects of KCND3 gene expression levels on ERP in both the left ventricle of the heart and in tibial artery.\n\nIn this study we identified for the first time a genome-wide significant association of a genetic variant with ERP. Our findings of a locus in the KCND3 gene not only provide insights into the genetic determinants but also into the pathophysiological mechanism of ERP, revealing a promising candidate for functional studies.

genetics↗

Predicting factors for long-term survival in patients with out-of-hospital cardiac arrest - a propensity score-matched analysis

BackgroundOut-of-hospital cardiac arrest (OHCA) is one of the leading causes of death worldwide, with acute coronary syndromes accounting for most of the cases.\n\nWhile the benefit of early revascularization has been clearly demonstrated in patients with ST-segment-elevation myocardial infarction (STEMI), diagnostic pathways remain unclear in the absence of STEMI. We aimed to characterize OHCA patients presenting to 2 tertiary cardiology centers and identify predicting factors associated with survival.\n\nMethodsWe retrospectively analyzed 519 patients after OHCA from February 2003 to December 2017 at 2 centers in Munich, Germany. Patients undergoing immediate coronary angiography (CAG) were compared to those without. Propensity score (PS) matching analysis and multivariate regression analysis were performed to identify predictors for improved outcome.\n\nResultsImmediate CAG was performed in 385 (74.1%) patients after OHCA with presumed cardiac cause of arrest.\n\nAs a result of multivariate analysis after propensity score matching, we found that ROSC at admission and immediate CAG were associated with better 30-days-survival [(OR, 6.54; 95% CI, 2.03-21.02), (OR, 2.41; 95% CI, 1.04-5.55)], and 1-year-survival [(OR, 4.49; 95% CI, 1.55-12.98), (OR, 2.54; 95% CI, 1.06-6.09)].\n\nConclusionsIn our study, ROSC at admission and immediate CAG were independent predictors of survival in cardiac arrest survivors. Improvement in prehospital management including bystander CPR and best practice post-resuscitation care with optimized triage of patients to an early invasive strategy may help ameliorate overall outcome of this critically-ill patient population.

epidemiology↗

A missense variant in Mitochondrial Amidoxime Reducing Component 1 gene and protection against liver disease

Analyzing 5770 all-cause cirrhosis cases and 572,850 controls from seven cohorts, we identify a missense variant in the Mitochondrial Amidoxime Reducing Component 1 gene (MARC1 p.A165T) that associates with protection from all-cause cirrhosis (OR 0.88, p=2.1*10-8). This same variant also associates with lower levels of hepatic fat on computed tomographic imaging and lower odds of physician-diagnosed fatty liver as well as lower blood levels of alanine transaminase (-0.012 SD, 1.4*10-8), alkaline phosphatase (-0.019 SD, 6.6*10-9), total cholesterol (-0.037 SD, p=1*10-18) and LDL cholesterol (-0.035 SD, p=7.3*10-16). Carriers of rare protein-truncating variants in MARC1 had lower liver enzyme levels, cholesterol levels, and reduced odds of liver disease (OR 0.19, p= 0.04) suggesting that deficiency of the MARC1 enzyme protects against cirrhosis.

genomics↗

Cis-epistasis at the LPA locus and risk of coronary artery disease

Identification of epistasis affecting complex human traits has been challenging. Focusing on known coronary artery disease (CAD) risk loci, we explore pairwise statistical interactions between 8,068 SNPs from ten CAD genome-wide association studies (n=30,180). We discovered rs1800769 and rs9458001 in the vicinity of the LPA locus to interact in modulating CAD risk (P=1.75x10-13). Specific genotypes (e.g., rs1800769 CT) displayed either significantly decreased or increased risk for CAD in the context of genotypes of the respective other SNP (e.g., rs9458001 GG vs. AA). In the UK Biobank (n=450,112) significant interaction of this SNP pair was replicated for CAD (P=3.09x10-22), and was also found for aortic valve stenosis (P=6.95x10-7) and peripheral arterial disease (P=2.32x10-4). Identical interaction patterns affected circulating lipoprotein(a) (n=5,953; P=8.7x10-32) and hepatic apolipoprotein(a) (apo(a)) expression (n=522, P=2.6x10-11). We further interrogated potential biological implications of the variants and propose a mechanism explaining epistasis that ultimately may translate to substantial cardiovascular risks.

genetics↗

Bayesian multiple logistic regression for meta-analyses of GWAS

Genetic variants in genome-wide association studies (GWAS) are tested for disease association mostly using simple regression, one variant at a time. Standard approaches to improve power in detecting disease-associated SNPs use multiple regression with Bayesian variable selection in which a sparsity-enforcing prior on effect sizes is used to avoid overtraining and all effect sizes are integrated out for posterior inference. For binary traits, the logistic model has not yielded clear improvements over the linear model. For multi-SNP analysis, the logistic model required costly and technically challenging MCMC sampling to perform the integration.\n\nHere, we introduce the quasi-Laplace approximation to solve the integral and avoid MCMC sampling. We expect the logistic model to perform much better than multiple linear regression except when predicted disease risks are spread closely around 0.5, because only close to its inflection point can the logistic function be well approximated by a linear function. Indeed, in extensive benchmarks with simulated phenotypes and real genotypes, our Bayesian multiple LOgistic REgression method (B-LORE) showed considerable improvements (1) when regressing on many variants in multiple loci at heritabilities [&ge;] 0.4 and (2) for unbalanced case-control ratios.\n\nB-LORE also enables meta-analysis by approximating the likelihood functions of individual studies by multivariate normal distributions, using their means and covariance matrices as summary statistics. Our work should make sparse multiple logistic regression attractive also for other applications with binary target variables. B-LORE is freely available from: https://github.com/soedinglab/b-lore.

genetics↗