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PURPOSE: The Mayo-Baylor RIGHT 10K Study enabled preemptive, sequence-based pharmacogenomics (PGx)-driven drug prescribing practices in routine clinical care within a large cohort. We also generated the tools and resources necessary for clinical PGx implementation and identified challenges to be overcome. Furthermore, we measured the frequency of both common genetic variation for which clinical guidelines already exist and that of rare variation that could be detected by DNA sequencing, rather than genotyping. METHODS: Targeted oligonucleotide-capture sequencing of 77 “pharmacogenes” was performed using DNA from 10,077 consented Mayo Clinic Biobank volunteers. The resulting predicted drug response related phenotypes for 13 genes, including CYP2D6 and HLA, affecting 21 drug-gene pairs, were deposited preemptively in the Mayo electronic health record (EHR). RESULTS: For the 13 pharmacogenes of interest, the genomes of 79% of participants carried clinically actionable variants in 3 or more genes and DNA sequencing identified an average of 3.3 additional conservatively predicted deleterious variants that would not have been evident using genotyping. CONCLUSIONS: Implementation of preemptive rather than reactive, sequence-based rather than genotype-based PGx prescribing revealed nearly universal patient applicability and required integrated institution-wide resources to fully realize individualized drug therapy and to demonstrate more efficient use of health care resources.

Purpose The development, implementation, and evaluation of a pharmacogenomics education program for pharmacists in a large, integrated multicampus health system are described. Summary Pharmacogenomics has been described as tailoring medications to each patient’s unique genetic sequence with the goals of minimizing harmful effects and optimizing therapeutic effects. Pharmacists are uniquely trained to lead the implementation of pharmacogenomics in clinical care. After assessment of pharmacists’ comfort with pharmacogenomics, different approaches were explored to develop, pilot test, and disseminate pharmacogenomics education across a multicampus academic medical center. Limited success with large-audience, single-lecture didactic education led to development and delivery of targeted, competency-based online modules using the institution’s academic virtual learning environment and course management system. Implementation steps included (1) collaboration with the Mayo Clinic Center for Individualized Medicine to create an interprofessional development team and project charter, (2) galvanizing pharmacy leadership support across multiple campuses, (3) development of competency-based interactive modules, and (4) assessment of the quality of and learner satisfaction with the modules. Significant improvements in competency scores were observed with each module and across the multiple campuses. Satisfaction with the education program was assessed at the end of a 4-module series. Conclusion A pharmacogenomics educational program targeting pharmacists was developed through interprofessional collaboration and provided a novel opportunity to construct an educational infrastructure to support enterprise health-system campuses with limited educational resources.

Shear stress, imposed on the vascular endothelium by circulating blood, critically sustains vascular synthesis of nitric oxide (NO). Endothelial NO synthase (eNOS) activity is determined by heat shock protein 90 (HSP90), caveolin-1, and the cofactor tetrahydrobiopterin (BH4). To determine whether increased blood flow concomitantly upregulates eNOS and GTP cyclohydrolase I (GTPCH I, the rate-limiting enzyme in BH4biosynthesis), an aortocaval fistula model in the rat was employed wherein aortic blood flow is enhanced proximal but decreased distal to the fistula. Eight weeks after the creation of the aortocaval fistula, the proximal and distal aortic segments were harvested; sham-operated rats served as controls. Vasomotor function was assessed by isometric force recording. Expression of eNOS, HSP90, caveolin-1, Akt, phosphorylated eNOS (eNOS-Ser1177), and GTPCH I were determined by Western blot analysis. Biosynthesis of BH4and GTPCH-I activity was examined by HPLC. In the aortic segments exposed to increased flow, contractions to KCl and phenylephrine were reduced, whereas endothelium-dependent relaxations were not affected compared with sham-operated or aortic segments with reduced blood flow. Expression of eNOS, caveolin-1, phosphorylated Akt, and eNOS-Ser1177 was enhanced in aortas exposed to increased blood flow. High flow augmented levels of cGMP and BH4and increased expression of GTPCH I. In aggregate, these findings provide the first demonstration in vivo that coordinated vascular upregulation of eNOS, and GTPCH I accompanies increased blood flow. This induction of GTPCH I increases BH4production, thereby optimizing the generation of NO by eNOS and thus the adaptive, vasorelaxant response required in sustaining increased blood flow.

Objective : Heart failure (HF) cell or siderophages are pulmonary macrophages that phagonicytize erythrocytes leaked from the congested capillaries due to HF. Degradation of erythrocytes and hemoglobin increases concentrations of heme in the lung. We hypothesized that the HF-induced increase in the concentration of heme up-regulates the expression and enzymatic activity of heme oxygenase (HO)-1 in the lung. Methods : Using the aortocaval (AC) fistula model of HF, we examined the following parameters 8–10 weeks after the creation of the fistula: morphological changes in the lung by Prussian blue iron and immunohistochemical staining, HO-1 protein expression and activity in the rat lungs, and concentrations of nitrite/nitrate (NO x −) and cyclic guanosine 3′,5′-monophospate (cGMP) of the lung homogenates. Results : Iron-stained siderophages were observed only in the lungs of rats with AC fistula. Protein level and enzyme activity of HO-1 were significantly enhanced in the lung of HF rats. NO x − concentrations of the two groups were similar, but cGMP was elevated in the lung of AC fistula rats (0.34 ± 0.06 vs. 0.89 ± 0.20 pmol/mg protein, P =0.025). Staining of serial sections of the lung tissues demonstrated induction of HO-1 co-localized to iron-stained siderophages. Conclusions : HF causes increased pulmonary HO-1 expression and activity, which emanates largely from siderophages. Up-regulation of HO-1 may have pulmonary protective in HF.

In cultured endothelial cells, the antioxidant, l -ascorbic acid (vitamin C), increases nitric oxide synthase (NOS) enzyme activity via chemical stabilization of tetrahydrobiopterin. Our objective was to determine the effect of vitamin C on NOS function and tetrahydrobiopterin metabolism in vivo. Twenty-six to twenty-eight weeks of diet supplementation with vitamin C (1%/kg chow) significantly increased circulating levels of vitamin C in wild-type (C57BL/6J) and apolipoprotein E (apoE)–deficient mice. Measurements of NOS enzymatic activity in aortas of apoE-deficient mice indicated a significant increase in total NOS activity. However, this increase was mainly due to high activity of inducible NOS, whereas eNOS activity was reduced. Significantly higher tetrahydrobiopterin levels were detected in aortas of apoE-deficient mice. Long-term treatment with vitamin C restored endothelial NOS activity in aortas of apoE-deficient mice, but did not affect activity of inducible NOS. In addition, 7,8-dihydrobiopterin levels, an oxidized form of tetrahydrobiopterin, were decreased and vascular endothelial function of aortas was significantly improved in apoE-deficient mice. Interestingly, vitamin C also increased tetrahydrobiopterin and NOS activity in aortas of C57BL/6J mice. In contrast, long-term treatment with vitamin E (2000 U/kg chow) did not affect vascular NOS activity or metabolism of tetrahydrobiopterin. In vivo, beneficial effect of vitamin C on vascular endothelial function appears to be mediated in part by protection of tetrahydrobiopterin and restoration of eNOS enzymatic activity.

Objective: Experimental hypercholesterolemia is associated with vasa vasorum neovascularization, unknown to occur before or after initial lesion formation. Thus, this study was performed to determine the temporal course of neovascularization of coronary vasa vasorum in relation to endothelial dysfunction, a hallmark of early atherosclerosis. Methods: Female domestic pigs were fed a normal diet (Group 1), a hypercholesterolemic diet for 2 and 4 weeks (Group 2), or a hypercholesterolemic diet for 6 and 12 weeks (Group 3). In vitro analysis of relaxation response to bradykinin served as an index for epicardial endothelial function. Spatial pattern and density of coronary vasa vasorum were assessed by three-dimensional microscopic computed tomography. Results: Relaxation response of coronary arteries to bradykinin was normal in both Group 1 (93±6%) and Group 2 (89±7%) but impaired in Group 3 (71±11%; P

The F2-isoprostanes are a family of novel prostaglandin isomers and a stable product of in vivo oxidative stress. 8-epi-prostaglandinF2 alpha, a member of this isoprostane family, is a vasoconstrictor and its local release may contribute to the abnormal vasomotor tone associated with hypercholesterolemia. We therefore aimed to outline the role of 8-epi-prostaglandinF2 alpha as a coronary vasoconstrictor in experimental hypercholesterolemia.Pigs were randomized to two experimental groups (each n = 9): normal (N) and high cholesterol (HC) diet. To determine the vasoconstrictive effects of 8-epi-prostaglandinF2 alpha in vitro, doses from 10(-9) to 10(-5) M were used to constrict coronary epicardial rings. Plasma total and LDL cholesterol levels were significantly higher in the HC group compared with the N group (P0.005) as were plasma 8-epi-prostaglandinF2 alpha levels (P0.001). 8-epi-prostaglandinF2 alpha immunoreactivity was present in the vessel wall in both groups. Normal vessels with intact endothelium (n = 8 rings) contracted to 8-epi-prostaglandinF2 alpha (maximal contraction 15.5 +/- 8.74%). In the HC group, rings with intact endothelium had a greater contractile response to 8-epi-prostaglandinF2 alpha compared to normals (72.3 +/- 7.9%; n = 8; P0.0001). This was reversed by preincubation with NOR-3, a NO donor (maximal contraction 6.7 +/- 1.56%; n = 5; P0.0001). Enhanced contraction in normal vessels occurred with endothelial denudation (98.4 +/- 3.56%; n = 6; P0.0001) and with preincubation of the endothelium-intact rings with L-NMMA (N-monomethyl-L-arginine), an NO synthase inhibitor (85.5 +/- 10.3%, n = 6, P0.001). The enhanced contraction seen with hypercholesterolemia did not occur with other prostanoid vasoconstrictors.Experimental hypercholesterolemia leads to a significant increase in 8-epi-prostaglandinF2 alpha levels in addition to enhanced 8-epi-prostaglandinF2 alpha-induced coronary vasoconstriction, in vitro. These findings support a role for the F2-isoprostanes in the regulation of coronary vasomotor tone in pathophysiologic states.

Abstract —Hypercholesterolemia is associated with increased circulating and tissue endothelin-1 immunoreactivity, decreased nitric oxide (NO) activity, and altered endothelial function. We tested the hypothesis that chronic endothelin receptor antagonism preserves endothelial function and increases NO in experimental porcine hypercholesterolemia. Pigs were randomized to 3 groups: Group 1, a 2% high-cholesterol (HC) diet alone (n=7); group 2, RO-48-5695, a combined endothelin receptor antagonist, and an HC diet (n=8); and group 3, ABT-627, a selective endothelin-A receptor antagonist, and an HC diet (n=8). Coronary epicardial and arteriolar endothelial function was determined by a dose-response relaxation to bradykinin (10 −11 to 10 −6 mol/L) , in all groups and in pigs maintained on a normal diet. Plasma total oxidized products of NO (NO x ) were determined by chemiluminescence at baseline and after 12 weeks. Bradykinin-stimulated coronary epicardial and arteriolar relaxation in group 1 was attenuated compared with normal-diet controls. This relaxation was normalized with endothelin receptor antagonism. Plasma NO x decreased after 12 weeks in group 1 (−74.8±5.5%). This decrease was attenuated in the endothelin receptor antagonist groups (group 2, −28.2±15.0%; group 3, −38.9±20.6%). Chronic endothelin receptor antagonism preserves coronary endothelial function and increases NO in hypercholesterolemia. This study supports a role of endothelin-1 in the regulation of NO activity and suggests a possible therapeutic role for endothelin receptor antagonists in hypercholesterolemia.

Abstract —Insulin and insulin-like growth factor (IGF) 1 affect coronary vasoactivity. Experimental hypercholesterolemia is associated with coronary atherogenesis and altered vasomotor regulation. Because the IGF axis is altered during atherogenesis, we postulated that experimental hypercholesterolemia is associated with an altered coronary vasoactive response to IGF-1 in vitro. Coronary arteries and arterioles from pigs fed either a normal or high-cholesterol diet for 10 weeks were contracted with endothelin-1 and relaxed with cumulative concentrations of insulin or IGF-1 (10 −12 to 10 −7 mol/L). Control arterioles were also incubated with the nitric oxide synthase inhibitor 10 −4 mol/L N G -monomethyl- l -arginine (L-NMMA) or the potassium channel blocker 10 −2 mol/L tetraethylammonium (TEA), contracted with endothelin-1, and relaxed with insulin or IGF-1. Experimental hypercholesterolemia (1) increased serum cholesterol (9.5±1.0 versus 1.9±0.08 mmol/L; P P =0.80) or IGF-1 ( P =0.12), and (4) significantly attenuated the arteriolar response to IGF-1 (maximal relaxation of 79±6% versus 42±8%; P =0.01) but not insulin (43±6% versus 53±7%; P =0.99). Control arteriolar vasorelaxation to IGF-1 was attenuated by both L-NMMA ( P P =0.01), whereas only L-NMMA attenuated insulin ( P P

Abstract —Insulin and insulin-like growth factor-I (IGF-I) may play a role in the modulation of coronary artery tone, yet there are few data regarding their vasoactive effects on the coronary vascular bed. We evaluated the vasorelaxation effects of insulin and IGF-I on porcine coronary epicardial vessels in vitro and elucidated possible mechanisms. Porcine epicardial arteries were contracted with 10 −7 mol/L endothelin-1 and relaxed with cumulative concentrations of either insulin or IGF-I (10 −12 to 10 −7 mol/L). The above experiments were repeated in vessels without endothelium. Vessels were also incubated with the nitric oxide synthase inhibitor N G -monomethyl- l -arginine (L-NMMA; 10 −4 mol/L) with and without 10 −3.5 mol/L l -arginine, the potassium channel blocker tetraethylammonium (TEA; 10 −2 mol/L), and the guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3,-α]quinoxalin-1-one (ODQ; 10 −5.5 mol/L); vessels were then contracted with endothelin-1 and relaxed with insulin or IGF-I. Insulin and IGF-I were also added after contraction with 60 mmol/L KCl. Insulin and IGF-I caused a similar decrease in coronary epicardial tension after contraction with endothelin-1 (relaxation of 28±4% [n=7] and 25±3% [n=8] with insulin and IGF-I, respectively; P l -Arginine did not reverse this effect of L-NMMA. KCl and TEA attenuated the vasorelaxation effect of both insulin and IGF-I. Thus, both insulin and IGF-I caused non–endothelium-dependent coronary vasorelaxation in vitro, probably through a mechanism involving the activation of potassium channels. These findings suggest that insulin and IGF-I participate in the regulation of coronary vasomotor tone.

Purpose: Evidence of a genetic predisposition to the development of inflammatory abdominal aortic aneurysms (AAAs) exists as a positive family history in 17% of patients. Familial clustering and other similarities between inflammatory AAAs and giant cell arteritis (GCA), which possesses a genetic risk determinant mapped to the HLA-DR molecule, suggest a role of genetic risk factors in inflammatory AAAs. The purpose of this study was to explore whether patients with inflammatory AAAs express disease-relevant genes associated with the HLA-DR region on the short arm of chromosome 6.Methods: Thirty-seven patients with histomorphologic findings of inflammatory AAA at operation were genotyped for the polymorphism of the HLA-DR B1 and HLA-DQ B1 alleles and compared to ethnically matched, healthy control subjects (n = 90).Results: Distribution of HLA-DR B1 alleles was nonrandom in patients with inflammatory AAAs versus control subjects. The HLA-DR B1 alleles B1*15 and B1*0404 were enriched in patients with inflammatory AAAs compared with control subjects (47% versus 27%, and 14% versus 3%; p < 0.05, respectively). Analysis of functionally relevant amino acid polymorphisms encoded by the HLA-DR B1 gene showed relevance at amino acid position 70. HLA-DR B1 alleles overrepresented in patients with inflammatory AAAs express a glutamine substitution at position 70, whereas alleles disfavored in the patient cohort express a negatively charged aspartic acid. Distribution of HLA-DQ B1 alleles were indistinguishable in patients and control subjects.Conclusion: These data indicate that a genetic risk determinant can be mapped to the HLA-DR B1 locus in patients with inflammatory AAAs. This association suggests a critical contribution of antigen binding in the pathogenesis of this disease. (J Vasc Surg 1997;25:356-64.)

Oxidative stress has been implicated as an important mechanism of vascular endothelial dysfunction induced by aging. Previous studies suggested that tetrahydrobiopterin (BH4), an essential cofactor of endothelial NO synthase, could be a molecular target for oxidation. We tested the hypothesis that oxidative stress, in particular oxidation of BH4, may contribute to attenuation of endothelium-dependent relaxation in aged mice. Vasomotor function of isolated carotid arteries was studied using a video dimension analyzer. Vascular levels of BH4and its oxidation products were measured via HPLC. In aged mice (age, 95 ± 2 wk), endothelium-dependent relaxation to ACh (10−5to 10−9M) as well as endothelium-independent relaxation to the NO donor diethylammonium ( Z)-1-( N, N-diethylamino)diazen-1-ium -1,2-diolate (DEA-NONOate, 10−5to 10−9M) were significantly reduced compared with relaxation detected in young mice (age, 23 ± 0.5 wk). Incubation of aged mouse carotid arteries with the cell-permeable SOD mimetic Mn(III)tetra(4-benzoic acid)porphyrin chloride normalized relaxation to ACh and DEA-NONOate. Furthermore, production of superoxide anion in aorta and serum levels of amyloid P component, which is the murine analog of C-reactive protein, was increased in old mice. In aorta, neither the concentration of BH4nor the ratio of reduced BH4to the oxidation products were different between young and aged mice. Our results demonstrate that in mice, aging impairs relaxation mediated by NO most likely by increased formation of superoxide anion. Oxidation of BH4does not appear to be an important mechanism underlying vasomotor dysfunction in aged mouse arteries.

Tetrahydrobiopterin (BH4) is an essential co-factor for endothelial nitric oxide synthase enzymatic activity. GTP cyclohydrolase I (GTPCH I) is the rate-limiting enzyme in BH4 synthesis. This study set out to test the hypothesis that in vivo gene transfer of GTPCH I to endothelial cells could increase bioavailability of BH4, enhance biosynthesis of nitric oxide and thereby enhance endothelium-dependent relaxations mediated by nitric oxide. In vivo gene transfer was carried out by adenovirus (Ad)-mediated delivery into rabbit carotid arteries. Each artery was transduced by 20-min intraluminal incubation of 109plaque-forming units of Ad-encoding GTPCH I (AdGTPCH) or β-galactosidase as a control. The rabbits were euthanized 72 h later, and vasomotor function of isolated arteries was assessed by isometric force recording. GTPCH I enzymatic activity, BH4, and oxidized biopterin levels were detected with the use of HPLC, and cGMP was measured with the use of radioimmunoassay. Expression of recombinant proteins was detected predominantly in endothelial cells. Both GTPCH I activity and BH4 levels were increased in arteries transduced with AdGTPCH. However, contraction to phenylephrine (10–5to 10–9M), endothelium-dependent relaxation to acetylcholine (10–5to 10–9M) and cGMP levels were not significantly affected by increased expression of GTPCH I. Our results suggest that expression of GTPCH I in vascular endothelium in vivo increases intracellular concentration of BH4. However, under physiological conditions, it appears that this increase does not affect nitric oxide production in endothelial cells of the carotid artery.

BACKGROUND: Insulin and insulin-like growth factor-I (IGF-I) are endogenous peptides with vasoactive activities. OBJECTIVE: To evaluate the vasodilatory effects of insulin and IGF-I on human vessels taken from patients with and without noninsulin-dependent diabetes mellitus (NIDDM) and to elucidate their mechanisms of action. METHODS: Vascular rings of human internal mammary artery (IMA) and saphenous vein harvested from 54 patients with and without NIDDM undergoing coronary bypass surgery were studied in vitro. RESULTS: For samples from patients without NIDDM both insulin and IGF-I (10(-12)-10(-7) mol/l) evoked greater relaxation in IMA rings (30 +/- 4 and 29 +/- 6%, maximal relaxation +/- SEM, respectively) than they did in saphenous-vein rings (43 +/- 4 and 42 +/- 5%, respectively, P < 0.05 both for insulin and for IGF-I). Similar results were obtained with vessels from patients with NIDDM. Relaxation was not affected by the removal of the endothelium and by inhibition of the production of nitric oxide. However, the vascular relaxation caused by insulin and IGF-I was completely abolished by KCI, and was attenuated by the nonspecific potassium-channel blocker tetraethylammonium (for IMA rings, to 77 +/- 8 and 66 +/- 4% with insulin and IGF-I, respectively; for saphenous vein rings, 73 +/- 2 and 77 +/- 1% for insulin and IGF-I, respectively, P < 0.001). CONCLUSIONS: Both insulin and IGF-I induced endothelial-independent, nitric oxide-independent vasorelaxation of rings from human IMA and saphenous veins, through a mechanism involving activation of potassium channels. This response remained intact in vessels from patients with NIDDM. This result supports the hypothesis that insulin and IGF-I play roles in the regulation of vascular tone in human vessels.

Objective: To examine the hypothesis that insulin and insulin-like growth factor I (IGF-I) attenuate endothelin-induced contraction of porcine coronary epicardial arteries in vitro. Background: Endothelin-induced coronary vasoconstriction is mediated by two types of receptors, A (ETA) and B (ETB), resulting in calcium influx. Both insulin and IGF-I attenuate endothelin-induced calcium influx into porcine coronary artery smooth muscle. Methods: Epicardial arteries harvested from juvenile pigs were contracted with cumulative concentrations of endothelin-1 (ETA- and ETB-receptor agonist; 10−10–10−6 M) or of sarafotoxin-6c (ETB-receptor agonist; 10−11–10−7 M). In additional experiments, endothelin-1 or sarafotoxin-6c were added after incubation with 10−8 M regular insulin or IGF-I. These experiments were repeated in vessels without endothelium. Contraction for each vessel was calculated relative to the response to 60 mM KCl. Results: The maximal contractions to endothelin-1 in vessels with and without endothelium were 158±8 and 200±21%, respectively ( p