In the title compound, C17H11Cl6NO4, the configuration of the cycloalkene skeleton is endo,cis. The benzene ring is twisted by 58.94 (8)° from the attached pyrrolidine ring. Two carbonyl groups play a key role in the crystal packing. A short intermolecular C⋯O distance of 3.017 (3) Å reveals that one carbonyl group is involved in dipole–dipole interactions, which link two adjacent enantiomers into an inversion dimer. Another carbonyl group provides an acceptor for the weak intermolecular C—H⋯O hydrogen bonds which link these dimers into layers parallel to (011).
crystal structure; tricyclo[5.2.1.02,6]dec-8-ene-3,5-dione; biological activity; cycloalkene skeleton; dipole–dipole interactions; hydrogen bonding
Thiazide diuretics have been associated with increased risk for new onset diabetes (NOD), but pharmacogenetic markers of thiazide-induced NOD are not well studied. Single nucleotide polymorphisms (SNPs) in the Transcription Factor 7-Like 2 gene (TCF7L2) represent the strongest and most reproducible genetic associations with diabetes. We investigated the association of tag SNPs in TCF7L2 with thiazide-induced NOD.
We identified cases that developed NOD and age, gender, and race/ethnicity-matched controls from the INternational VErapamil SR Trandolapril STudy (INVEST). INVEST compared cardiovascular outcomes between two antihypertensive treatment strategies in ethnically diverse patients with hypertension and coronary artery disease. We genotyped 101 TCF7L2 tag SNPs and used logistic regression to test for pharmacogenetic (SNP*hydrochlorothiazide treatment) interactions. Permuted interaction p values were corrected with the PACT test and adjusted for diabetes-related variables.
In INVEST whites, we observed three TCF7L2 SNPs with significant SNP*treatment interactions for NOD. The strongest pharmacogenetic interaction was observed for rs7917983 (synergy index 3.37 [95%CI 1.72–6.59], p=5.0×10−4, PACT =0.03), which was associated with increased NOD risk in hydrochlorothiazide-treated patients (OR 1.53 [1.04–2.25], p=0.03) and decreased NOD risk in non hydrochlorothiazide-treated patients (OR 0.48 [0.27–0.86], p=0.02). The TCF7L2 SNP rs4506565, previously associated with diabetes, showed a similar, significant pharmacogenetic association.
Our results suggest that hydrochlorothiazide treatment is an environmental risk factor that increases diabetes risk beyond that attributed to TCF7L2 variation in white, hypertensive patients. Further study and replication of our results is needed to confirm pharmacogenetic influences of TCF7L2 SNPs on thiazide-induced NOD.
pharmacogenetics; TCF7L2; diabetes mellitus; hydrochlorothiazide
Regulation of angiogenesis is critical for many diseases. Specifically, pathological retinal neovascularization, a major cause of blindness, is suppressed with dietary ω3-long-chain polyunsaturated fatty acids (ω3LCPUFAs) through antiangiogenic metabolites of cyclooxygenase and lipoxygenase. Cytochrome P450 epoxygenases (CYP2C8) also metabolize LCPUFAs, producing bioactive epoxides, which are inactivated by soluble epoxide hydrolase (sEH) to transdihydrodiols. The effect of these enzymes and their metabolites on neovascularization is unknown.
Approach and Results
The mouse model of oxygen-induced retinopathy was used to investigate retinal neovascularization. We found that CYP2C (localized in wild-type monocytes/macrophages) is upregulated in oxygen-induced retinopathy, whereas sEH is suppressed, resulting in an increased retinal epoxide:diol ratio. With a ω3LCPUFA-enriched diet, retinal neovascularization increases in Tie2-driven human-CYP2C8–overexpressing mice (Tie2-CYP2C8-Tg), associated with increased plasma 19,20-epoxydocosapentaenoic acid and retinal epoxide:diol ratio. 19,20-Epoxydocosapentaenoic acids and the epoxide:diol ratio are decreased with overexpression of sEH (Tie2-sEH-Tg). Overexpression of CYP2C8 or sEH in mice does not change normal retinal vascular development compared with their wild-type littermate controls. The proangiogenic role in retina of CYP2C8 with both ω3LCPUFA and ω6LCPUFA and antiangiogenic role of sEH in ω3LCPUFA metabolism were corroborated in aortic ring assays.
Our results suggest that CYP2C ω3LCPUFA metabolites promote retinal pathological angiogenesis. CYP2C8 is part of a novel lipid metabolic pathway influencing retinal neovascularization.
angiogenesis factor; cytochrome P450 CYP2C8 (human); pathologic neovascularization
Nanoparticles (NPs) are becoming increasingly widespread in the environment. Free cadmium ions released from commonly used NPs under ultraviolet-B (UV-B) radiation are potentially toxic to living organisms. With increasing levels of UV-B radiation at the Earth’s surface due to the depletion of the ozone layer, the potential additive effect of NPs and UV-B radiation on plants is of concern. In this study, we investigated the synergistic effect of CdTe quantum dots (CdTe-QDs), a common form of NP, and UV-B radiation on wheat seedlings. Graded doses of CdTe-QDs and UV-B radiation were tested, either alone or in combination, based on physical characteristics of 5-day-old seedlings. Treatments of wheat seedlings with either CdTe-QDs (200 mg/L) or UV-B radiation (10 KJ/m2/d) induced the activation of wheat antioxidant enzymes. CdTe-QDs accumulation in plant root cells resulted in programmed cell death as detected by DNA laddering. CdTe-QDs and UV-B radiation inhibited root and shoot growth, respectively. Additive inhibitory effects were observed in the combined treatment group. This research described the effects of UV-B and CdTe-QDs on plant growth. Furthermore, the finding that CdTe-QDs accumulate during the life cycle of plants highlights the need for sustained assessments of these interactions.
Type 2 diabetes mellitus (T2DM) accounts for the majority of diabetes cases and affects a significant proportion of the adult population worldwide. Calpain-10 has been implicated in the development of type 2 diabetes, and some polymorphisms in the CAPN10 gene have been associated with an increased risk of developing this disease. Several molecular epidemiological studies were conducted in recent years to evaluate the association between the CAPN10 rs2975760 polymorphism and T2DM risk in diverse populations. However, the results remain conflicting rather than conclusive. We performed a meta-analysis of 8 case-control studies that included 2758 T2DM cases and 2762 case-free controls. We assessed the strength of the association, using odds ratios (ORs) with 95% confi dence intervals (CIs). Overall, this meta-analysis showed that the CAPN10 rs2975760 polymorphism was not associated with a significantly type 2 diabetes risk in three genetic models. However, after excluding two study for its heterogeneity, a significantly increased risk was found in all comparisons (for C vs T: OR=1.14, 95% CI=1.03-1.27, I
b=0.012; for TC vs TT: OR=1.15, 95% CI=1.01-1.30, I
b=0.030; for CC+TC vs TT: OR=1.16, 95% CI=1.03-1.31, I
b=0.015). No publication bias was found in the present study. This meta-analysis suggests that the C allele of the CAPN10 rs2975760 polymorphism is associated with an increased T2DM risk. Further large and well-designed studies are needed to confi rm this association.
Type 2 diabetes mellitus; calpain-10; polymorphism; meta-analysis
Diabetic retinopathy, the main microvascular complications of diabetes and one of the leading causes of blindness worldwide. Interesting reports on the role of inflammatory/proangiogenic high mobility group 1 (HMGB-1) cytokine and phospholipases A2 (PLA2) in neovascularization have diverted our concentration to reveal whether HMGB-1 and PLA2 plays role in diabetic retinopathy.
We performed our study in streptozotocin (STZ)-induced diabetic rat model. The expression levels of the cytokines, chemokines, and cell adhesion molecules in retinal tissues were evaluated by quantitative RT-PCR. HMGB-1 and PLA2 protein levels along with VEGF, TNF-α, IL-1β and ICAM-1 levels were also measured.
We observed the retinal pericytes, endothelial injury/death and breakdown of blood–retinal barrier (BRB). The protein expression of HMGB-1, PLA2 and IL-1β were significantly increased in micro vessels from retina of diabetic rats. Diabetic rats had also high retinal levels of VEGF, ICAM-1 and TNF-α. Further investigation revealed that pericyte death is mediated by HMGB-1-induced cytotoxic activity of glial cells, while HMGB-1 can directly mediate endothelial cell death. Similarly, increased expression of PLA2 represents the diabetic mediated alteration of BRB, perhaps up regulating the VEGF.
Our data suggest that HMGB-1 and PLA2 involved in retinal pericyte and endothelial injury and cell death in diabetic retinopathy. From this study, we suggest that HMGB-1 and PLA2 may be interesting targets in managing diabetic retinopathy.
Blood retinal barrier; Micro vessels; Retinal pericytes; Endothelial cells
Angiogenesis is mediated by signaling through receptor tyrosine kinases (RTKs), Src family kinases and adhesion receptors such as integrins, yet the mechanism how these signaling pathways regulate one another remains incompletely understood. The RTK modulator, Sprouty4 (Spry4) inhibits endothelial cell functions and angiogenesis, but the mechanisms remain to be fully elucidated. In this study, we demonstrate that Spry4 regulates angiogenesis in part by regulating endothelial cell migration. Overexpression of Spry4 in human endothelial cells inhibited migration and adhesion on vitronectin (VTN), whereas knockdown of Spry4 enhanced these behaviors. These activities were shown to be c-Src-dependent and Ras-independent. Spry4 disrupted the crosstalk between vascular endothelial growth factor-2 and integrin αVβ3, the receptor for VTN. Spry4 overexpression resulted in decreased integrin β3 protein levels in a post-transcriptional manner in part by modulating its tyrosine phosphorylation by c-Src. Conversely, knockdown of Spry4 resulted in increased integrin β3 protein levels and tyrosine phosphorylation. Moreover, in vivo analysis revealed that Spry4 regulated integrin β3 levels in murine embryos and yolk sacs. Our findings identify an unanticipated role for Spry4 in regulating c-Src activity and integrin β3 protein levels, which contributes to the regulation of migration and adhesion of endothelial cells. Thus, targeting Spry4 may be exploited as a target in anti-angiogenesis therapies.
Sprouty; c-Src; integrins; angiogenesis; endothelial cell migration
Recent advances have shown that histology and genetic biomarkers are important
in patient selection, which have led to significantly better outcomes for lung
cancer patients. However, most new treatments only apply to adenocarcinoma or
non-squamous, and in squamous carcinoma there is little breakthrough. In a phase
III trial nab-paclitaxel plus carboplatin showed superior response rate over
paclitaxel and carboplatin. In subgroup analysis the squamous histology appeared
to be a predictive factor to nab-paclitaxel treatment.
This is an open-label, randomized, active controlled phase II trial. A total
of 120 untreated advanced squamous lung cancer patients are randomized at a 1:1
ratio to receive nab-paclitaxel (135 mg/m2, d1, 8, q3w)
plus carboplatin (AUC 5, d1, q3w) or gemcitabine
(1,250 mg/m2, d1, 8, q3w) and carboplatin (AUC 5, d1,
q3w). The primary endpoint is objective response rate and the second endpoints are
progression free survival, overall survival, safety and biomarkers associated with
nab-paclitaxel. The treatment will continue up to six cycles or intolerable
This ongoing trial will be the first prospective randomized trial to explore
the efficacy of nab-paclitaxel as the first-line treatment specifically in
squamous carcinoma of lung.
Clinicaltrials.gov reference: NCT01236716
Nab-paclitaxel; Carboplatin; Gemcitabine; Squamous; Carcinoma; Lung
To characterize macular thickness (MT) changes in Leber’s hereditary optic neuropathy (LHON) patients by cirrus HD-optical coherence tomography (OCT), and to study the correlation between MT and best corrected visual acuity (BCVA).
Fifty-two eyes from 52 consecutive LHON patients and 14 eyes from 14 age- and sex-matched healthy controls were scanned by OCT. Affected eyes were classified into five groups according to disease duration (1st group: ≤3 months; 2nd group: 3–6 months; 3rd group: 6–9 months; 4th group: 9–12 months; and 5th group: >12 months). MT was compared and analyzed. The correlation between BCVA and MT was calculated.
Less than six months after LHON onset, the cube average thickness (CAT) and the MT in the superior, nasal, inferior, and temporal quadrants of the inner ring and the MT in the nasal quadrant of the outer ring were decreased (P < 0.005); at 3–6 months onset, the MT of the temporal quadrants of the outer ring was decreased (P = 0.045); after 6 months, the MT was significantly thinner in all measurements (P < 0.01) except for the central ring. The BCVA was significantly different between each group and controls (P < 0.05), but there was no significant correlation among the five groups (P = 0.666). There was no significant correlation between the BCVA and CAT (P = 0.893).
The MT thinned before the retinal nerve fiber layer and this occurred with a particular sequence. Our results provide potential diagnostic information for LHON.
Leber’s hereditary optic neuropathy; Optical coherence tomography; Retinal nerve fiber layer; Macular thickness
Angina and hypertension are common in patients with coronary artery disease (CAD), however the effect on mortality is unclear. We conducted this prespecified analysis of the INternational VErapamil/Trandolapril STudy (INVEST) to assess relationships between angina, blood pressure (BP), and mortality among elderly, hypertensive CAD patients.
Angina and elevated BP will be associated with higher mortality.
Methods and Results
Extended follow-up was performed using the National Death Index for INVEST patients in the United States (n=16,951). Based on angina history at enrollment and during follow-up visits, patients were divided into groups: persistent (n=7184), new onset (n=899), resolved (n=4070), or never (n=4798). BP was evaluated at baseline, during drug titration and during follow-up on-treatment. On-treatment systolic BP was classified as tightly controlled (<130 mmHg), controlled (130–139 mmHg), or uncontrolled (≥140 mmHg). A Cox proportional hazards model was created adjusting for age, heart failure, diabetes, renal impairment, myocardial infarction, stroke, and smoking. The angina groups and BP control groups were compared using the never angina group as the reference. Only in the persistent angina group was a significant association with mortality observed, with an apparent protective effect (HR 0.82, 95% CI 0.75 to 0.89, P <0.0001). Uncontrolled BP was associated with increased mortality risk (HR 1.29, 95% CI 1.20 to 1.40, P <0.0001), as were several other known cardiovascular risk factors.
In hypertensive CAD patients, persistent angina was associated with lower mortality. The observed effect was small compared with other cardiovascular risk factors, such as BP, which were associated with increased mortality.
Angina; Hypertension; Coronary disease; Prognosis; Myocardial infarction
To identify novel genes influencing blood pressure response to thiazide diuretic therapy for hypertension, we conducted genome-wide association meta-analyses of ≈1.1 million single nucleotide polymorphisms in a combined sample of 424 European Americans with primary hypertension treated with hydrochlorothiazide from the Pharmacogenomic Evaluation of Antihypertensive Responses Study (N=228) and the Genetic Epidemiology of Responses to Antihypertensive Study (N=196). Polymorphisms associated with blood pressure response at p<10-5 were tested for replication of the associations in independent samples of hydrochlorothiazide-treated European hypertensives. The rs16960228 polymorphism in protein kinase C, alpha replicated for same-direction association with diastolic blood pressure response in the Nordic Diltiazem Study (N=420) and the Genetics of Drug Responsiveness in Essential Hypertension Study (N=206), and the combined four-study meta-analysis p-value achieved genome-wide significance (p=3.3 × 10-8). Systolic/diastolic blood pressure responses were consistently greater in carriers of the rs16960228 A allele than in GG homozygotes (4/4 mmHg greater) across study samples. The rs2273359 polymorphism in the GNAS-EDN3 region also replicated for same-direction association with systolic blood pressure response in the Nordic Diltiazem Study, and the combined three-study meta-analysis p-value approached genome-wide significance (p=5.5 × 10-8). The findings document clinically-important effects of genetic variation at novel loci on blood pressure response to a thiazide diuretic, which may be a basis for individualization of antihypertensive drug therapy and identification of new drug targets.
Hypertension; high blood pressure; antihypertensive therapy/diuretics; hydrochlorothiazide; genomics; pharmacogenomics; protein kinase C
We sought to identify novel pharmacogenetic markers associated with cardiovascular outcomes in patients with hypertension on antihypertensive therapy. We genotyped a 1:4 case:control cohort (n=1345) on the Illumina HumanCVD Beadchip from the International Verapamil SR-Trandolapril Study, where participants were randomized to a β blocker strategy or a calcium channel blocker strategy. Genome-spanning SNP × treatment interaction analyses of non-synonymous SNPs were conducted in white and Hispanic race/ethnic groups. Top hits from whites were tested in Hispanics for consistency. A genetic risk score was constructed from the top three signals and tested in the Nordic Diltiazem study. SIGLEC12 rs16982743 and A1BG rs893184 had a significant interaction with treatment strategy for adverse cardiovascular outcomes (International Verapamil SR-Trandolapril Study whites and Hispanics combined interaction P=0.0038, and 0.0036, respectively). A genetic risk score including rs16982743, rs893184 and rs4525 in F5, was significantly associated with treatment-related adverse cardiovascular outcomes in whites and Hispanics from the International Verapamil SR-Trandolapril Study and in the Nordic Diltiazem study (meta-analysis interaction P=2.39×10−5). In patients with a genetic risk score of zero or 1, calcium channel blocker treatment was associated with lower risk (OR (95% CI) = 0.60 (0.42-0.86)), and in those with a genetic risk score of 2-3, calcium channel blocker treatment was associated with higher risk, OR (95% CI) = 1.31 (1.08-1.59)). These results suggest cardiovascular outcomes may differ based on SIGLEC12, A1BG, F5 genotypes and antihypertensive treatment strategy. These specific genetic associations and our risk score provide insight into a potential approach to personalized antihypertensive treatment selection.
Pharmacogenomics; Hypertension; antihypertensive agents; cardiovascular outcomes; genetic variation; beta-blockers, calcium channel blockers
Blood pressure (BP) is a heritable determinant of risk for cardiovascular disease (CVD). To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP), we genotyped ∼50 000 single-nucleotide polymorphisms (SNPs) that capture variation in ∼2100 candidate genes for cardiovascular phenotypes in 61 619 individuals of European ancestry from cohort studies in the USA and Europe. We identified novel associations between rs347591 and SBP (chromosome 3p25.3, in an intron of HRH1) and between rs2169137 and DBP (chromosome1q32.1 in an intron of MDM4) and between rs2014408 and SBP (chromosome 11p15 in an intron of SOX6), previously reported to be associated with MAP. We also confirmed 10 previously known loci associated with SBP, DBP, MAP or PP (ADRB1, ATP2B1, SH2B3/ATXN2, CSK, CYP17A1, FURIN, HFE, LSP1, MTHFR, SOX6) at array-wide significance (P < 2.4 × 10−6). We then replicated these associations in an independent set of 65 886 individuals of European ancestry. The findings from expression QTL (eQTL) analysis showed associations of SNPs in the MDM4 region with MDM4 expression. We did not find any evidence of association of the two novel SNPs in MDM4 and HRH1 with sequelae of high BP including coronary artery disease (CAD), left ventricular hypertrophy (LVH) or stroke. In summary, we identified two novel loci associated with BP and confirmed multiple previously reported associations. Our findings extend our understanding of genes involved in BP regulation, some of which may eventually provide new targets for therapeutic intervention.
Aspirin or dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is standard therapy for patients at increased risk for cardiovascular events. However, the genetic determinants of variable response to aspirin (alone and in combination with clopidogrel) are not known.
Methods and Results
We measured ex-vivo platelet aggregation before and after DAPT in individuals (n=565) from the Pharmacogenomics of Antiplatelet Intervention (PAPI) Study and conducted a genome-wide association study (GWAS) of drug response. Significant findings were extended by examining genotype and cardiovascular outcomes in two independent aspirin-treated cohorts: 227 percutaneous coronary intervention (PCI) patients, and 1,000 patients of the International VErapamil SR/trandolapril Study (INVEST) GENEtic Substudy (INVEST-GENES). GWAS revealed a strong association between single nucleotide polymorphisms on chromosome 1q23 and post-DAPT platelet aggregation. Further genotyping revealed rs12041331 in the platelet endothelial aggregation receptor-1 (PEAR1) gene to be most strongly associated with DAPT response (P=7.66×10−9). In Caucasian and African American patients undergoing PCI, A-allele carriers of rs12041331 were more likely to experience a cardiovascular event or death compared to GG homozygotes (hazard ratio = 2.62, 95%CI 0.96-7.10, P=0.059 and hazard ratio = 3.97, 95%CI 1.10-14.31, P=0.035 respectively). In aspirin-treated INVEST-GENES patients, rs12041331 A-allele carriers had significantly increased risk of myocardial infarction compared to GG homozygotes (OR=2.03, 95%CI 1.01-4.09, P=0.048).
Common genetic variation in PEAR1 may be a determinant of platelet response and cardiovascular events in patients on aspirin, alone and in combination with clopidogrel.
Clinical Trial Registration Information
clinicaltrials.gov; Identifiers: NCT00799396 and NCT00370045
pharmacogenomics; platelets; percutaneous coronary intervention; PEAR1; CYP2C19
Single-nucleotide polymorphisms (SNPs) in NEDD4L may influence the ability of the NEDD4L protein to reduce epithelial sodium channel expression. A variant in NEDD4L, rs4149601, was associated with antihypertensive response and cardiovascular outcomes during treatment with thiazide diuretics and β-blockers in a Swedish population. We sought to further evaluate associations between NEDD4L polymorphisms, blood pressure response and cardiovascular outcomes with thiazide diuretics and β-blockers.
Four SNPs, rs4149601, rs292449, rs1008899 and rs75982813, were genotyped in 767 patients from the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) clinical trial and association was assessed with blood pressure response to hydrochlorothiazide and atenolol. One SNP, rs4149601, was also genotyped in 1345 patients from the International Verapmil SR Trandolapril Study (INVEST), and association was examined with adverse cardiovascular outcomes relative to hydrochlorothiazide treatment.
Significant associations or trends were found between rs4149601, rs292449, rs75982813 and rs1008899 and decreases in blood pressure in whites on hydrochlorothiazide, and a significant association was observed with increasing copies of the GC rs4149601-rs292449 haplotype and greater blood pressure response to hydrochlorothiazide in whites (P = 0.0006 and 0.006, SBP and DBP, respectively). Significant associations were also seen with rs4149601 and an increased risk for adverse cardiovascular outcomes in whites not treated with hydrochlorothiazide [P = 0.022, odds ratio (95% confidence interval) = 10.65 (1.18–96.25)].
NEDD4L rs4149601, rs292449 and rs75982813 may be predictors for blood pressure response to hydrochlorothiazide in whites, and NEDD4L rs4149601 may be a predictor for adverse cardiovascular outcomes in whites not treated with hydrochlorothiazide.
epithelial sodium channel; hypertension; International Verapamil SR Trandolapril Study; neural precursor cell expressed developmentally down-regulated 4 like; Pharmacogenomic Evaluation of Antihypertensive Responses; pharmacogenetics
Uncontrolled asthma is a major cause of hospitalizations and emergency room visits. Factors including obesity, African ancestry and childhood are associated with increased asthma severity. Considering the high morbidity caused by asthma, relatively few classes of drugs exist to control this common disease. Therefore, new therapeutic strategies may be needed to reduce asthma’s impact on public health. Data suggest that a high fat diet that is deficient in omega-3 fatty acids could promote both obesity and excessive inflammation, resulting in greater asthma severity. Small trials with supplemental omega-3 fatty acids have been conducted with encouraging but inconsistent results. The variability in response seen in past trials may be due to the past subjects’ genetics (specifically ALOX5 rs59439148) or their particular asthma phenotypes. Therefore, the “Nutrigenetic response to Omega-3 Fatty acids in Obese Asthmatics (NOOA)” trial is currently underway and was designed as a randomized, double-blind, placebo controlled intervention study to determine if supplemental omega-3 fatty acids improves symptoms among obese adolescents and young adults with uncontrolled asthma. Here we report the design and rationale for the NOOA trial. Participants were given either 3.18g daily of eicosapentaenoic acid and 822mg daily docosahexaenoic acid, or matched control soy oil, for 24 weeks. Change in the asthma control questionnaire score was the primary outcome. Secondary outcomes included spirometry, impulse oscillometry, exacerbation rate, airway biomarkers, systemic inflammation, leukotriene biosynthesis and T-lymphocyte function. NOOA may lead to a new therapeutic treatment strategy and greater understanding of the mechanistic role of diet in the pathogenesis of asthma.
Asthma Control; Obesity; Children; Nutrigenetics; Omega-3 Fatty Acids
To date, 39 SNPs have been associated with blood pressure (BP) or hypertension (HTN) in genome-wide association studies (GWAS) in Caucasians. Our hypothesis is that the loci/SNPs associated with BP/HTN are also associated with BP response to antihypertensive drugs.
Methods and Results
We assessed the association of these loci with BP response to atenolol or hydrochlorothiazide monotherapy in 768 hypertensive participants in the Pharmacogenomics Responses of Antihypertensive Responses (PEAR) study. Linear regression analysis was performed in Caucasians for each SNP in an additive model adjusting for baseline BP, age, gender and principal components for ancestry. Genetic scores were constructed to include SNPs with nominal associations and empirical p values were determined by permutation test. Genotypes of 37 loci were obtained from Illumina 50K cardiovascular or Omni1M GWAS chips. In Caucasians, no SNPs reached Bonferroni-corrected alpha of 0.0014, six reached nominal significance (p<0.05) and 3 were associated with atenolol BP response at p < 0.01. The genetic score of the atenolol BP lowering alleles was associated with response to atenolol (p =3.3*10−6 for SBP; p=1.6*10−6 for DBP). The genetic score of the HCTZ BP lowering alleles was associated with response to HCTZ (p = 0.0006 for SBP; p = 0.0003 for DBP). Both risk score p values were < 0.01 based on the empirical distribution from the permutation test.
These findings suggest selected signals from hypertension GWAS may predict BP response to atenolol and HCTZ when assessed through risk scoring.
beta-blocker; diuretics; hypertension; pharmacogenetics; polymorphisms blood pressure
A recent genome-wide analysis discovered an association between a haplotype (from rs317689/rs315135/rs7297610) on Chromosome 12q15 and blood pressure response to hydrochlorothiazide in African-Americans. Our aim was to replicate this association and investigate possible functional mechanisms. We observed similar associations between this haplotype and hydrochlorothiazide response in an independent sample of 746 Caucasians and African-Americans randomized to hydrochlorothiazide or atenolol treatment. The haplotype association was driven by variation at rs7297610, where C/C genotypes were associated with greater mean (systolic: 3.4mmHg, P=0.0275; diastolic: 2.5mmHg, P=0.0196) responses to hydrochlorothiazide vs. T-allele carriers. Such an association was absent in atenolol-treated participants, supporting this as hydrochlorothiazide-specific. Expression analyses in hydrochlorothiazide-treated African-Americans showed differential leukocyte YEATS4 expression between rs7297610 genotype groups at baseline (P=0.024), and reduced expression in C/C genotypes (P=0.009), but not in T-carriers. Our data confirm previous genome-wide findings at 12q15 and suggest differential YEATS4 expression could underpin rs7297610-associated HCTZ response variability, which may have future implications for guiding thiazide treatment.
hydrochlorothiazide; hypertension; pharmacogenomics; blood pressure; YEATS4; diuretics
In the present study, the changes in the retinal nerve fiber layer (RNFL) thickness associated with Leber’s hereditary optic neuropathy (LHON) were examined by Cirrus high definition-optical coherence tomography (OCT), and the correlation between the RNFL thickness and the best corrected visual acuity (BCVA) was evaluated. A cross-sectional study was performed. Sixty-eight eyes from patients with LHON and 30 eyes from healthy individuals were scanned. Affected eyes were divided into 5 groups according to disease duration: Group 1, ≤3 months; group 2, 4–6 months; group 3, 7–9 months; group 4, 10–12 months; and group 5, >12 months. The RNFL thickness of the temporal, superior, nasal and inferior quadrants and the 360° average were compared between the LHON groups and the control group. The eyes in groups 1 and 2 were observed to have a thicker RNFL in the superior, nasal and inferior quadrants and a higher 360°-average RNFL thickness compared with those of the control group (P<0.05), the RNFL was observed to be thinner in the temporal quadrant in groups 1 and 2. The eyes in groups 3 and 4 showed a thinner RNFL in the temporal (P=0.001), superior and inferior (both P<0.05) quadrants, and a lower 360°-average RNFL thickness as compared with controls (P=0.001). No significant correlation was identified between BCVA and RNFL thickness. RNFL thickness was observed to undergo a unique process from thickening to thinning in the patients with LHON. Changes in different quadrants occurred at different time periods and the BCVA was not found to be correlated with RNFL thickness.
Leber’s hereditary optic neuropathy; optical coherence tomography; retinal nerve fiber layer
We sought to identify novel pharmacogenomic markers for HDL-C response to atenolol in participants with mild to moderate hypertension. We genotyped 768 hypertensive participants from the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) study on the Illumina HumanCVD Beadchip. During PEAR, participants were randomized to receive atenolol or hydrochlorothiazide. Blood pressure and cholesterol levels were evaluated at baseline and after treatment. This study focused on participants treated with atenolol monotherapy. Association with atenolol induced HDL-C change was evaluated in 232 whites and 152 African Americans using linear regression. No SNPs achieved a Bonferroni corrected P-value. However, we identified 13 regions with consistent association across whites and African Americans. The most interesting of these regions were seven with prior associations with HDL-C, other metabolic traits, or functional implications in the lipid pathway: GALNT2, FTO, ABCB1, LRP5, STARD3NL, ESR1, and LIPC. Examples are rs2144300 in GALNT2 in whites (P=2.29x10-4, β=-1.85 mg/dL) and rs12595985 in FTO in African Americans (P=2.90x10-4, β=4.52 mg/dL), both with consistent regional association (P<0.05) in the other race group. Additionally, baseline GALNT2 expression differed by rs2144300 genotype in whites (P=0.0279). In conclusion, we identified multiple gene regions associated with atenolol induced HDL-C change that were consistent across race groups, several with functional implications or prior associations with HDL-C.
G protein-coupled receptor kinases (GRKs) are important regulatory proteins for many G protein-coupled receptors, but little is known about GRK4 pharmacogenetics. We hypothesized three nonsynonymous GRK4 SNPs, R65L (rs2960306), A142V (rs1024323) and A486V (rs1801058) would be associated with blood pressure response to atenolol, but not hydrochlorothiazide, and would be associated with long term cardiovascular outcomes (all cause, death, nonfatal myocardial infarction, nonfatal stroke) in participants treated with an atenolol-based versus verapamil-SR-based antihypertensive strategy. GRK4 SNPs were genotyped in 768 hypertensive participants from the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) trial. In Caucasians and African Americans, increasing copies of the variant 65L-142V haplotype were associated with significantly reduced atenolol-induced diastolic blood pressure lowering (−9.1 ± 6.8 vs −6.8 ± 7.1 vs −5.3 ± 6.4 mmHg in participants with 0, 1 and 2 copies of 65L-142V respectively; p=0.0088). 1460 participants with hypertension and coronary artery disease from the INternational VErapamil SR / Trandolapril STudy (INVEST) were genotyped and variant alleles of all three GRK4 SNPs were associated with increased risk for adverse cardiovascular outcomes in an additive fashion, with 486V homozygotes reaching statistical significance (Odds ratio 2.29 [1.48–3.55], p=0.0002). These effects on adverse cardiovascular outcomes were independent of antihypertensive treatment. These results suggest the presence of GRK4 variant alleles may be important determinants of blood pressure response to atenolol and risk for adverse cardiovascular events. The associations with GRK4 variant alleles were stronger in patients who were also ADRB1 389R-homozygotes, suggesting a potential interaction between these two genes.
hypertension; GRK4; atenolol; beta-blocker; outcomes; ADRB1; pharmacogenetics
Dichloroacetate (DCA), a chemical relevant to environmental science and allopathic medicine, is dehalogenated by the bifunctional enzyme glutathione transferase zeta (GSTz1) maleylacetoacetate isomerase (MAAI), the penultimate enzyme in the phenylalanine/tyrosine catabolic pathway. The authors postulated that polymorphisms in GSTz1/MAAI modify the toxicokinetics of DCA. GSTz1/MAAI haplotype significantly affected the kinetics and biotransformation of 1,2-13C-DCA when it was administered at either environmentally (μg/kg/d) or clinically (mg/kg/d) relevant doses. GSTz1/MAAI haplotype also influenced the urinary accumulation of potentially toxic tyrosine metabolites. Atomic modeling revealed that GSTz1/MAAI variants associated with the slowest rates of DCA metabolism induced structural changes in the enzyme homodimer, predicting protein instability or abnormal protein-protein interactions. Knowledge of the GSTz1/MAAI haplotype can be used prospectively to identify individuals at potential risk of DCA’s adverse side effects from environmental or clinical exposure or who may exhibit aberrant amino acid metabolism in response to dietary protein.
dichloroacetate; glutathione transferase zeta; maleylacetoacetate isomerase; pharmacogenetics; toxicogenetics; tyrosine metabolism
It is difficult to accurately determine prognosis of patients with hypertension and chronic stable coronary artery disease (CAD). Our aim was to construct a risk score for predicting important adverse events in this population.
Methods and Results
Patients with hypertension and chronic stable CAD enrolled in the INternational VErapamil‐SR/Trandolapril STudy (INVEST) comprised the study cohort. Candidate predictor variables were obtained from patients with at least 1 postbaseline visit. Patients were divided into development (n=18 484) and validation cohorts (n=2054). Cox regression model identified predictors of the primary outcome: all‐cause mortality, myocardial infarction, or stroke at a mean follow‐up of 2.3 years. The hazard ratio of each variable was rounded to the nearest integer to construct score weights. A score 0 to 4 defined low‐risk, 5 to 6 intermediate‐risk and ≥7 high‐risk. The following variables were retained in the final model: age, residence, body mass index, on‐treatment heart rate and BP, prior myocardial infarction, heart failure, stroke/transient ischemic attack, smoking, diabetes, peripheral arterial disease, and chronic kidney disease. The primary outcome occurred in 2.9% of the low‐risk group, 6.5% of the intermediate‐risk group, and 18.0% of the high‐risk group (P for trend <0.0001). The model was good at discriminating those who had an event versus those who did not (C‐statistic=0.75). The model performed well in a validation cohort (C‐statistic=0.77).
Readily available clinical variables can rapidly stratify patients with hypertension and chronic stable CAD into useful risk categories.
clinical decision rule; coronary artery disease; coronary heart disease; ischemic heart diseae; prognosis; risk score
AIM: To study the effects of low-dose amitriptyline (AMT) on gastrointestinal function and brain-gut peptides in healthy Chinese volunteers.
METHODS: This was a double-blind, randomised, placebo-controlled, two-period cross-over trial. Twenty-eight healthy volunteers were randomised and administered 1-wk treatments of AMT (12.5 mg tid) or placebo. Before and during the final two days of treatment, gastric emptying, proximal gastric accommodation and visceral sensitivity were measured by drinking-ultrasonography test; the orocecal transit time (OCTT) was measured by lactulose hydrogen breath test, and fasting blood was collected. Plasma levels of ghrelin, motilin and neuropeptide Y (NPY) were measured by enzyme-linked immunosorbent assay kits.
RESULTS: AMT slowed the OCTT (109.2 ± 29.68 min vs 96.61 ± 23.9 min, P = 0.004) but did not affect liquid gastric emptying and had no effect on proximal gastric accommodation. AMT resulted in decreases in the visual analogue scale (VAS) for difficulty in drinking 600 and 800 mL of water (3.57 ± 0.94 vs 2.98 ± 0.85, 5.57 ± 0.82 vs 4.57 ± 0.98, P < 0.01 for both), although it had no significant effect on the VAS for difficulty in drinking 200 mL and 400 mL of water. AMT significantly increased the plasma ghrelin level (442.87 ± 176.79 pg/mL vs 526.87 ± 158.44 pg/mL, P = 0.04) and the neuropeptide-Y level (890.15 ± 131.46 pg/mL vs 965.64 ± 165.63 pg/mL, P = 0.03), whereas it had no effect on the MTL level.
CONCLUSION: Low-dose AMT could slow OCTT, make the stomach less sensitive and increase the plasma levels of ghrelin and NPY. Thus, we recommend the use of low-dose AMT for functional gastrointestinal disorders.
Amitriptyline; Orocecal transit time; Visceral hypersensitivity; Gastric emptying; Brain-gut peptides