Inherited Variants in SCARB1 Cause Severe Early-Onset Coronary Artery Disease

Rationale: Coronary artery disease (CAD) is a pervasive and critical healthcare problem. Elevated high density lipoprotein-associated cholesterol (HDL-C) is associated with improved atherosclerotic cardiovascular disease (ASCVD) outcomes on a population level, but clinical trials aimed at HDL-C elevation have not succeeded in improving ASCVD event risk. Nevertheless, human variants in the HDL receptor, encoded by SCARB1, are associated with dyslipidemia, suggesting that HDL metabolism, not HDL-C, is a suitable target for therapy. However, variants in SCARB1 have never been directly attributed to CAD by Mendelian inheritance. Objective: To determine if compound heterozygous variants in SCARB1 cause disease in two brothers with severe, early-onset CAD. Methods and Results: Using whole exome sequencing, we have identified rare, compound heterozygous variants in SCARB1 that segregate with severe, premature CAD, following patterns of Mendelian inheritance. Using induced pluripotent stem cell-derived hepatocyte-like cells (iPSC-HLCs) from the proband, we discovered the maternal variant (c.754_755delinsC) to be the first identified SCARB1 null allele, characterized by the absence of RNA and protein expression. Further, we demonstrate that the variant on the paternal allele (c.956G>T (p.G319V)) results in decreased cholesterol uptake, decreased SR-BI:HDL binding, and increased affinity for SR-BI dimerization. Finally, we generated a p.G319V knock-in mouse model that displays nearly 100% homozygous lethality and elevated plasma cholesterol in heterozygous animals, confirming pathogenicity of this variant. Conclusions: In summary, our data provide the first molecular mechanism to show the Mendelian inheritance of CAD as a result of human SCARB1 variants. The rarity of these variants supports pathogenicity in this family. Furthermore, SR-BI p.G319V, which has previously been reported benign in the context of heterozygosity, was uniquely presented alongside a null allele, demonstrating the disease-contributing capability of loss-of-function SCARB1 variants within the population.

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Elevated level of circulatory sTLT1 induces inflammation through SYK/MEK/ERK signalling in coronary artery disease

Clinical Science ◽

10.1042/cs20190999 ◽

2019 ◽

Vol 133 (22) ◽

pp. 2283-2299

Author(s):

Apabrita Ayan Das ◽

Devasmita Chakravarty ◽

Debmalya Bhunia ◽

Surajit Ghosh ◽

Prakash C. Mandal ◽

...

Keyword(s):

Risk Factors ◽

Coronary Artery Disease ◽

Coronary Artery ◽

Chronic Inflammation ◽

Ex Vivo ◽

Human Subjects ◽

Critical Role ◽

Atherosclerotic Cardiovascular Disease ◽

Tnf Α ◽

Artery Disease

Abstract The role of inflammation in all phases of atherosclerotic process is well established and soluble TREM-like transcript 1 (sTLT1) is reported to be associated with chronic inflammation. Yet, no information is available about the involvement of sTLT1 in atherosclerotic cardiovascular disease. Present study was undertaken to determine the pathophysiological significance of sTLT1 in atherosclerosis by employing an observational study on human subjects (n=117) followed by experiments in human macrophages and atherosclerotic apolipoprotein E (apoE)−/− mice. Plasma level of sTLT1 was found to be significantly (P<0.05) higher in clinical (2342 ± 184 pg/ml) and subclinical cases (1773 ± 118 pg/ml) than healthy controls (461 ± 57 pg/ml). Moreover, statistical analyses further indicated that sTLT1 was not only associated with common risk factors for Coronary Artery Disease (CAD) in both clinical and subclinical groups but also strongly correlated with disease severity. Ex vivo studies on macrophages showed that sTLT1 interacts with Fcɣ receptor I (FcɣRI) to activate spleen tyrosine kinase (SYK)-mediated downstream MAP kinase signalling cascade to activate nuclear factor-κ B (NF-kB). Activation of NF-kB induces secretion of tumour necrosis factor-α (TNF-α) from macrophage cells that plays pivotal role in governing the persistence of chronic inflammation. Atherosclerotic apoE−/− mice also showed high levels of sTLT1 and TNF-α in nearly occluded aortic stage indicating the contribution of sTLT1 in inflammation. Our results clearly demonstrate that sTLT1 is clinically related to the risk factors of CAD. We also showed that binding of sTLT1 with macrophage membrane receptor, FcɣR1 initiates inflammatory signals in macrophages suggesting its critical role in thrombus development and atherosclerosis.

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A polygenic risk score for coronary artery disease predicts early-onset myocardial infarction and mortality in men

Archives of Cardiovascular Diseases Supplements ◽

10.1016/j.acvdsp.2021.04.131 ◽

2021 ◽

Vol 13 (2) ◽

pp. 201

Author(s):

H.D. Manikpurage ◽

A. Eslami ◽

N. Perrot ◽

Z. Li ◽

C. Couture ◽

...

Keyword(s):

Myocardial Infarction ◽

Coronary Artery Disease ◽

Coronary Artery ◽

Risk Score ◽

Early Onset ◽

Polygenic Risk Score ◽

Polygenic Risk ◽

Artery Disease

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Abstract 12291: Contribution of Rare Mutations in Mendelian Hypercholesterolemia Genes to Risk for Premature Coronary Artery Disease in the Population

Circulation ◽

10.1161/circ.130.suppl_2.12291 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Hong-Hee Won ◽

Ron Do ◽

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Null Allele ◽

Coronary Revascularization ◽

Null Alleles ◽

Premature Coronary Artery Disease ◽

Rare Mutations ◽

Increased Risk ◽

Artery Disease ◽

Cad Risk

Introduction: Low-density lipoprotein cholesterol (LDL-C) is a causal risk factor for coronary artery disease (CAD). Rare mutations in at least 6 genes lead to Mendelian forms of high or reduced LDL-C; three ( APOB, LDLR, PCSK9 ) act in a dominant pattern whereas three ( ABCG5, ABCG8, LDLRAP1 ) in a recessive pattern. We address to what extent rare mutations in Mendelian LDL-C genes contribute to early CAD risk in the population. Methods: We sequenced the exons of the 6 genes in 9,329 early CAD cases (myocardial infarction, angiographic CAD, or coronary revascularization in men≤50 and women≤60) and 10,245 controls from 9 studies using targeted and whole exome next-generation sequencing. We tested 3 sets: ‘Null alleles’ (nonsense, splice-site, or frameshift); ‘Deleterious (7/7)’ (null and missense annotated as damaging by 7 algorithms); and ‘Deleterious (6/7)’ (null and missense annotated as damaging by at least 6 algorithms). Given the rarity of deleterious mutations, we aggregated these mutations in each gene and tested for an excess or deficit in cases vs . controls. Results: Counts of mutations are provided in Table. Null mutations in LDLR , carried by 1:500 participants, confered a 8-fold increase in CAD risk (P=8х10 -7 ) whereas heterozygosity for a null mutation in ABCG5 (1:650 frequency) was associated with a 3-fold increased risk (P=5х10 -3 ). ‘Deleterious (7/7)’ mutations in LDLR , carried by 1:100 participants, confered a 4-fold increased risk (P=8х10 -17 ) whereas heterozygosity for a ‘Deleterious (7/7)’ mutation in ABCG5 (1:250 frequency) was associated with a 2-fold increased risk (P=2х10 -3 ). Heterozygous null allele carriers at LDLR and ABCG5 had increased LDL-C (P<0.001). Conclusions: Of early CAD cases, 2-3% carry a rare, deleterious mutation at LDLR or ABCG5 associated with increased risk. Although previously reported to cause recessive sitosterolemia, we find that heterozygosity for a null allele at ABCG5 is associated with markedly higher early CAD risk.

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Loss of SR-BI Expression Leads to the Early Onset of Occlusive Atherosclerotic Coronary Artery Disease, Spontaneous Myocardial Infarctions, Severe Cardiac Dysfunction, and Premature Death in Apolipoprotein E–Deficient Mice

Circulation Research ◽

10.1161/hh0302.104462 ◽

2002 ◽

Vol 90 (3) ◽

pp. 270-276 ◽

Cited By ~ 286

Author(s):

Anne Braun ◽

Bernardo L. Trigatti ◽

Mark J. Post ◽

Kaori Sato ◽

Michael Simons ◽

...

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Apolipoprotein E ◽

Cardiac Dysfunction ◽

Early Onset ◽

Premature Death ◽

Myocardial Infarctions ◽

Artery Disease ◽

Deficient Mice

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Cardiovascular Prognosis in Drug-Resistant Hypertension Stratified by 24-Hour Ambulatory Blood Pressure: The JAMP Study

Hypertension ◽

10.1161/hypertensionaha.121.18198 ◽

2021 ◽

Author(s):

Kazuomi Kario ◽

Satoshi Hoshide ◽

Keisuke Narita ◽

Yukie Okawara ◽

Hiroshi Kanegae ◽

...

Keyword(s):

Blood Pressure ◽

Cardiovascular Disease ◽

Coronary Artery Disease ◽

Risk Factor ◽

Coronary Artery ◽

Ambulatory Blood Pressure ◽

Resistant Hypertension ◽

Cardiovascular Events ◽

Atherosclerotic Cardiovascular Disease ◽

Artery Disease

Resistant hypertension is an important cardiovascular risk factor. This analysis of the JAMP study (Japan Ambulatory Blood Pressure Monitoring Prospective) data investigated the effects of uncontrolled resistant hypertension diagnosed using ambulatory blood pressure (BP) monitoring on the risk of heart failure (HF) and overall cardiovascular events. The JAMP study patients with hypertension and no HF history were included. They had true resistant hypertension (24-hour BP ≥130/80 mm Hg), pseudoresistant hypertension (24-hour BP <130/80 mm Hg), well-controlled nonresistant hypertension (24-hour BP <130/80 mm Hg), or uncontrolled nonresistant hypertension (24-hour BP ≥130/80 mm Hg). The primary end point was total cardiovascular events, including atherosclerotic cardiovascular disease (fatal/nonfatal stroke and fatal/nonfatal coronary artery disease), and HF. During 4.5±2.4 years of follow-up the overall incidence per 1000 person-years was 10.1 for total cardiovascular disease, 4.1 for stroke, 3.5 for coronary artery disease, and 2.6 for HF. The adjusted risk of total cardiovascular and HF events was significantly increased in patients with true resistant versus controlled nonresistant hypertension (hazard ratio, 1.66 [95% CI, 1.12–2.48]; P =0.012 and 2.24 [95% CI, 1.17–4.30]; P =0.015, respectively) and versus uncontrolled nonresistant hypertension (1.51 [1.03–2.20]; P =0.034 and 3.03 [1.58–5.83]; P <0.001, respectively). The findings were robust in a sensitivity analysis using a slightly different definition of resistant hypertension. True resistant hypertension diagnosed using ambulatory BP monitoring is a significant independent risk factor for cardiovascular disease events, especially for HF. This highlights the importance of diagnosing and effectively treating resistant hypertension. Registration: URL: https://www.umin.ac.jp/ctr ; Unique identifier: UMIN000020377.

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