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Inhibition of soluble epoxide hydrolase (sEH, EPHX2) elicits potent cardiovascular protective effects in preclinical models of ischemic cardiovascular disease (CVD), and genetic polymorphisms in EPHX2 have been associated with developing ischemic CVD in humans. However, it remains unknown whether EPHX2 variants are associated with prognosis following an ischemic CVD event. We evaluated the association between EPHX2 p.Lys55Arg and p.Arg287Gln genotype with survival in 667 acute coronary syndrome (ACS) patients. No association with p.Arg287Gln genotype was observed (P = 0.598). Caucasian EPHX2 Arg55 carriers (Lys/Arg or Arg/Arg) had a significantly higher risk of 5-year mortality (adjusted hazard ratio [HR] 1.61, 95% confidence interval [CI] 1.01-2.55, P = 0.045). In an independent population of 2712 ACS patients, this association was not replicated (adjusted HR 0.92, 95% CI 0.70-1.21, P = 0.559). In a secondary analysis, Caucasian homozygous Arg55 allele carriers (Arg/Arg) appeared to exhibit a higher risk of cardiovascular mortality (adjusted HR 2.60, 95% CI 1.09-6.17). These results demonstrate that EPHX2 p.Lys55Arg and p.Arg287Gln polymorphisms do not significantly modify survival after an ACS event. Investigation of other sEH metabolism biomarkers in ischemic CVD appears warranted.

AIM:To determine the projected impact of a multigene pharmacogenetic (PGx) test on medication prescribing. MATERIALS & METHODS:A retrospective analysis was conducted with 122 cardiac catheterization laboratory patients undergoing angiography for eligibility of potential PGx-guided interventions that could have occurred if multigene PGx information was pre-emptively available at the time of the procedure. Medication data and presence of actionable at-risk genotypes were used to determine eligibility of a PGx intervention. RESULTS:20% of the study population (n = 24) would have qualified for at least one PGx-based medication intervention per US FDA or Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines within 6 months of their cardiac catheterization procedure. Commonly encountered gene-drug pairs for these interventions included: CYP2C19 for clopidogrel and antidepressants, CYP2D6 for antidepressants and codeine, SLCO1B1 for simvastatin, and VKORC1/CYP2C9 for warfarin. CONCLUSION:Pre-emptive use of a multigene PGx test in the cardiac catheterization laboratory offers potential to reduce adverse medication outcomes.

The ABCD‐GENE score was developed to predict poor response to clopidogrel and includes Age, Body mass index, Chronic kidney disease (CKD; estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m2), Diabetes, and CYP2C19 GENE variants; a score ≥ 10 is predictive of reduced clopidogrel effectiveness after percutaneous coronary intervention (PCI). Estimation of GFR without a race variable via the CKD‐EPI Scr 2021 equation is now recommended. We examined the impact of using the CKD‐EPI Scr 2021 vs. 2009 equation on the ABCD‐GENE score for post‐PCI patients. A total of 4335 adult patients (n = 925 Black) who underwent PCI and CYP2C19 genotyping were included, with GFR estimated for each patient via the CKD‐EPI Scr 2021 and CKD‐EPI 2009 equations. The ABCD‐GENE score, calculated based on each GFR estimation, was compared. With the CKD‐EPI Scr 2021 vs. 2009 equation, median (IQR) eGFR was lower (74 [55–94] vs. 81 [60–103] mL/min/1.73 m2, P < 0.001), and CKD prevalence was higher (31% vs. 25%, P < 0.001) among Black patients, whereas eGFR was higher (85 [65–99] vs. 80 [61–94] mL/min/1.73m2, P < 0.001), and CKD prevalence was lower (20% vs. 24%, P < 0.001) in non‐Black patients. This led to 12 (1%) Black patients being reclassified from low to high risk of poor clopidogrel response and 30 (1%) non‐Black patients being recategorized from high to low risk (P < 0.001 for both comparisons). Removal of the race variable from GFR estimation significantly impacted the prediction of clopidogrel effectiveness via the ABCD‐GENE score. [ABSTRACT FROM AUTHOR]

Beta‐blockers are widely used medications for a variety of indications, including heart failure, myocardial infarction, cardiac arrhythmias, and hypertension. Genetic variability in pharmacokinetic (e.g., CYP2D6) and pharmacodynamic (e.g., ADRB1, ADRB2, ADRA2C, GRK4, GRK5) genes have been studied in relation to beta‐blocker exposure and response. We searched and summarized the strength of the evidence linking beta‐blocker exposure and response with the six genes listed above. The level of evidence was high for associations between CYP2D6 genetic variation and both metoprolol exposure and heart rate response. Evidence indicates that CYP2D6 poor metabolizers experience clinically significant greater exposure and lower heart rate in response to metoprolol compared with those who are not poor metabolizers. Therefore, we provide therapeutic recommendations regarding genetically predicted CYP2D6 metabolizer status and metoprolol therapy. However, there was insufficient evidence to make therapeutic recommendations for CYP2D6 and other beta‐blockers or for any beta‐blocker and the other five genes evaluated (updates at www.cpicpgx.org). [ABSTRACT FROM AUTHOR]

We recently demonstrated that selective expression of the Rho GTPase-activating protein ARHGAP42 in smooth muscle cells (SMCs) controls blood pressure by inhibiting RhoA-dependent contractility, providing a mechanism for the blood pressure-associated locus within the ARHGAP42 gene. The goals of the current study were to identify polymorphisms that affect ARHGAP42 expression and to better assess ARHGAP42's role in the development of hypertension. Using DNase I hypersensitivity methods and ENCODE data, we have identified a regulatory element encompassing the ARHGAP42 SNP rs604723 that exhibits strong SMC-selective, allele-specific activity. Importantly, CRISPR/Cas9-mediated deletion of this element in cultured human SMCs markedly reduced endogenous ARHGAP42 expression. DNA binding and transcription assays demonstrated that the minor T allele variation at rs604723 increased the activity of this fragment by promoting serum response transcription factor binding to a cryptic cis-element. ARHGAP42 expression was increased by cell stretch and sphingosine 1-phosphate in a RhoA-dependent manner, and deletion of ARHGAP42 enhanced the progression of hypertension in mice treated with DOCA-salt. Our analysis of a well-characterized cohort of untreated borderline hypertensive patients suggested that ARHGAP42 genotype has important implications in regard to hypertension risk. Taken together, our data add insight into the genetic mechanisms that control blood pressure and provide a potential target for individualized antihypertensive therapies.

Cytochrome P450 (CYP)-derived epoxyeicosatrienoic acids (EETs) exhibit potent cardiovascular protective effects in preclinical models, and promoting the effects of EETs has emerged as a potential therapeutic strategy for coronary artery disease (CAD). The relationship between circulating EET levels and CAD extent in humans, however, remains unknown. A panel of free (unesterified) plasma eicosanoid metabolites was quantified in 162 patients referred for coronary angiography, and associations with extent of CAD [no apparent CAD (N = 39), nonobstructive CAD (N = 51), and obstructive CAD (N = 72)] were evaluated. A significant relationship between free EET levels and CAD extent was observed (P = 0.003) such that the presence of obstructive CAD was associated with lower circulating EET levels. This relationship was confirmed in multiple regression analysis where CAD extent was inversely and significantly associated with EET levels (P = 0.013), and with a biomarker of EET biosynthesis (P < 0.001), independent of clinical and demographic factors. Furthermore, quantitative enrichment analysis revealed that these associations were the most pronounced compared with other eicosanoid metabolism pathways. Collectively, these findings suggest that the presence of obstructive CAD is associated with lower EET metabolite levels secondary to suppressed EET biosynthesis. Novel strategies that promote the effects of EETs may have therapeutic promise for patients with obstructive CAD.

Cardiovascular disease, including acute myocardial infarction (AMI), is the leading cause of morbidity and mortality globally, despite well-established treatments. The discovery and development of novel therapeutics that prevent the progression of devastating consequences following AMI are thus important in reducing the global burden of this devastating disease. Scientific evidence for the protective effects of epoxyeicosatrienoic acids (EETs) in the cardiovascular system is rapidly emerging and suggests that promoting the effects of these cytochrome P450-derived epoxyeicosanoids is a potentially viable clinical therapeutic strategy. Through a translational lens, this review will provide insight into the potential clinical utility of this therapeutic strategy for AMI by 1) outlining the known cardioprotective effects of EETs and underlying mechanisms demonstrated in preclinical models of AMI with a particular focus on myocardial ischemia-reperfusion injury, 2) describing studies in human cohorts that demonstrate a relationship between EETs and associated pathways with coronary artery disease risk, and 3) discussing preclinical and clinical areas that require further investigation in order to increase the probability of successfully translating this rapidly emerging body of evidence into a clinically applicable therapeutic strategy for AMI.

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor (clopidogrel, prasugrel, or ticagrelor) is indicated after percutaneous coronary intervention (PCI) to reduce the risk of atherothrombotic events. Approximately 30% of the US population has a CYP2C19 no‐function allele that reduces the effectiveness of clopidogrel, but not prasugrel or ticagrelor, after PCI. We have shown improved outcomes with the integration of CYP2C19 genotyping into clinical care to guide the selection of prasugrel or ticagrelor in CYP2C19 no‐function allele carriers. However, the influence of patient‐specific demographic, clinical, and other genetic factors on outcomes with genotype‐guided DAPT has not been defined. In addition, the impact of genotype‐guided de‐escalation from prasugrel or ticagrelor to clopidogrel in patients without a CYP2C19 no‐function allele has not been investigated in a diverse, real‐world clinical setting. The Precision Antiplatelet Therapy after Percutaneous Coronary Intervention (Precision PCI) Registry is a multicenter US registry of patients who underwent PCI and clinical CYP2C19 testing. The registry is enrolling a diverse population, assessing atherothrombotic and bleeding events over 12 months, collecting DNA samples, and conducting platelet function testing in a subset of patients. The registry aims to define the influence of African ancestry and other patient‐specific factors on clinical outcomes with CYP2C19‐guided DAPT, evaluate the safety and effectiveness of CYP2C19‐guided DAPT de‐escalation following PCI in a real‐world setting, and identify additional genetic influences of clopidogrel response after PCI, with the ultimate goal of establishing optimal strategies for individualized antiplatelet therapy that improves outcomes in a diverse, real‐world population. [ABSTRACT FROM AUTHOR]

Epoxyeicosatrienoic acids (EETs), lipid mediators produced by cytochrome P450 epoxygenases, regulate inflammation, angiogenesis, and vascular tone. Despite pleiotropic effects on cells, the role of these epoxyeicosanoids in normal organ and tissue regeneration remains unknown. EETs are produced predominantly in the endothelium. Normal organ and tissue regeneration require an active paracrine role of the microvascular endothelium, which in turn depends on angiogenic growth factors. Thus, we hypothesize that endothelial cells stimulate organ and tissue regeneration via production of bioactive EETs. To determine whether endothelial-derived EETs affect physiologic tissue growth in vivo, we used genetic and pharmacological tools to manipulate endogenous EET levels. We show that endothelial-derived EETs play a critical role in accelerating tissue growth in vivo, including liver regeneration, kidney compensatory growth, lung compensatory growth, wound healing, corneal neovascularization, and retinal vascularization. Administration of synthetic EETs recapitulated these results, whereas lowering EET levels, either genetically or pharmacologically, delayed tissue regeneration, demonstrating that pharmacological modulation of EETs can affect normal organ and tissue growth. We also show that soluble epoxide hydrolase inhibitors, which elevate endogenous EET levels, promote liver and lung regeneration. Thus, our observations indicate a central role for EETs in organ and tissue regeneration and their contribution to tissue homeostasis.

Cyclooxygenase (COX)-derived prostaglandins and cytochrome P450 (CYP) epoxygenase-derived epoxyeicosatrienoic acids are important regulators of inflammation; however, functional interactions between these pathways in the regulation of vascular inflammation in vivo have not been studied. We investigated the relative and additive effects of endothelial CYP2J2 overexpression (Tie2-CYP2J2-Tr), global sEH disruption (Ephx2(-/-)), and pharmacologic COX inhibition with indomethacin on the acute vascular inflammatory response to endotoxin in mice. Compared to vehicle-treated wild-type C57BL/6 controls, induction of myeloperoxidase (MPO) activity in lung and liver was similarly attenuated in Tie2-CYP2J2-Tr mice, Ephx2(-/-) mice and wild-type mice treated with moderate dose indomethacin. Dual modulation of both pathways, however, did not produce an additive anti-inflammatory effect. These findings demonstrate that both COX and CYP epoxygenase-mediated eicosanoid metabolism are important regulators of the acute vascular inflammatory response in vivo, and suggest that the anti-inflammatory effects of modulating each pathway may be mediated, at least in part, by overlapping mechanisms.