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The relationship between either paraoxonase 1 (PON1) gene promoter DNA methylation or genetic variations and bleeding or major adverse cardiac events after dual antiplatelet therapy has been incompletely characterized. We aimed to systematically investigate the role of genetic variations and DNA methylation of the PON1 CpG island promoter on the clinical outcomes of dual antiplatelet therapy for patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI). This study included 653 patients with CAD undergoing PCI and receiving dual antiplatelet therapy. Genomic DNAs were isolated from whole blood and were genotyped for the three single nucleotide polymorphisms (SNPs) of the PON1 gene. The DNA methylation levels in the PON1 promoter region were determined by bisulfite sequencing or pyrosequencing at five CpG sites (positions −142, −161, −163, −170, and −184 from the transcription start site). Clopidogrel and its metabolites in plasma were examined using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and platelet function analysis was performed using the VerifyNow assay. Statistically significant associations between methylation levels at five PON1 CpG sites and bleeding were observed: −184 [odds ratio (OR) 0.98, 95% confidence interval (CI) 0.96–1.00, p = 0.028]; −170 (OR 0.99, 95% CI 0.97–1.00, p = 0.048); −163 (OR 0.98, 95% CI 0.96–1.00, p = 0.029); −161 (OR 0.98, 95% CI 0.97–1.00, p = 0.026); and −142 (OR 0.98, 95% CI 0.97–1.00, p = 0.042) at a false discovery rate of

Diabetic patients continue to develop inflammation and cardiovascular complication even after achieving glycemic control, suggesting a "metabolic memory". Metabolic memory is a major challenge in the treatment of diabetic complication, and the mechanisms underlying metabolic memory are not clear. Recent studies suggest a link between chromatin histone methylation and metabolic memory. In this study, we tested whether histone 3 lysine-9 tri-methylation (H3K9me3), a key epigenetic chromatin marker, was involved in high glucose (HG)-induced inflammation and metabolic memory. Incubating cardiomyocyte cells in HG resulted in increased levels of inflammatory cytokine IL-6 mRNA when compared with myocytes incubated in normal culture media, whereas mannitol (osmotic control) has no effect. Chromatin immunoprecipitation (ChIP) assays showed that H3K9me3 levels were significantly decreased at the promoters of IL-6. Immunoblotting demonstrated that protein levels of the H3K9me3 methyltransferase, Suv39h1, were also reduced after HG treatment. HG-induced apoptosis, mitochondrial dysfunction and cytochrome-c release were reversible. However, the effects of HG on the expression of IL-6 and the levels of H3K9me3 were irreversible after the removal of HG from the culture. These results suggest that HG-induced sustained inflammatory phenotype and epigenetic histone modification, rather than HG-induced mitochondrial dysfunction and apoptosis, are main mechanisms responsible for metabolic memory. In conclusion, our data demonstrate that HG increases expression of inflammatory cytokine and decreases the levels of histone-3 methylation at the cytokine promoter, and suggest that modulating histone 3 methylation and inflammatory cytokine expression may be a useful strategy to prevent metabolic memory and cardiomyopathy in diabetic patients.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Bupropion, an antidepressant and smoking cessation drug, is metabolized to its active metabolite hydroxybupropion almost exclusively by CYP2B6. • Ginkgo biloba is among the most commonly used herbal extract in the general population, and is likely to be used by depressed patients receiving bupropion. • Studies have reported that G. biloba administration to rats markedly increased the CYP content and CYP2B mRNA in the liver, and intake of G. biloba also induced various hepatic CYP enzymes, especially CYP2B-type enzymes. • There may be drug interactions between G. biloba extract and bupropion (CYP2B6 substrate). WHAT THIS STUDY ADDS • Fourteen-day oral administration of G. biloba extract had no statistically significant effect on the pharmacokinetics of bupropion or its active metabolite hydroxybupropion, as measured by AUC, which suggests G. biloba does not significantly affect the metabolism of bupropion following a single oral dose in healthy Chinese men. AIMS To assess the effects of Ginkgo biloba extract on the pharmacokinetics of bupropion in healthy volunteers. METHODS Fourteen healthy male volunteers (age range 19–25 years) received orally administered bupropion (150 mg) alone and during treatment with G. biloba 240 mg day−1 (two 60-mg capsules taken twice daily) for 14 days. Serial blood samples were obtained over 72 h after each bupropion dose, and used to derive pharmacokinetic parameters of bupropion and its CYP2B6-catalysed metabolite, hydroxybupropion. RESULTS Ginkgo biloba extract administration resulted in no significant effects on the AUC0–∞ of bupropion and hydroxybupropion. Bupropion mean AUC0–∞ value was 1.4 µg·h ml−1[95% confidence interval (CI) 1.2, 1.6] prior to G. biloba treatment and 1.2 µg·h ml−1 (95% CI 1.1, 1.4) after 14 days of treatment. Hydroxybupropion mean AUC0–∞ value was 8.2 µg·h ml−1 (95% CI 6.5, 10.4) before G. biloba administration and 8.7 µg·h ml−1 (95% CI 7.1, 10.6) after treatment. The Cmax of hydroxybupropion increased from 221.8 ng ml−1 (95% CI 176.6, 278.6) to 272.7 ng ml−1 (95% CI 215.0, 345.8) (P = 0.038) and the t1/2 of hydroxybupropion fell from 25.0 h (95% CI 22.7, 27.5) to 21.9 h (95% CI 19.9, 24.1) (P = 0.000). CONCLUSIONS Ginkgo biloba extract administration for 14 days does not significantly alter the basic pharmacokinetic parameters of bupropion in healthy volunteers. Although G. biloba extract treatment appears to reduce significantly the t1/2 and increase the Cmax of hydroxybupropion, no bupropion dose adjustments appear warranted when the drug is administered orally with G. biloba extract, due to the lack of significant change observed in AUC for either bupropion or hydroxybupropion.

Background:Ginkgo biloba is one of the most popular herbal supplements in the world. The supplement has been shown to induce the enzymatic activity of CYP2C19, the main cytochrome P450 isozyme involved in voriconazole metabolism. Because this enzyme exhibits genetic polymorphism, the inductive effect was expected to be modulated by the CYP2C19 metabolizer status.Objective:To examine the possible effects of Ginkgo biloba as an inducer of CYP2C19 on single-dose pharmacokinetics of voriconazole in Chinese volunteers genotyped as either CVP2C19 extensive or poor metabolizers.Methods:Fourteen healthy, nonsmoking volunteers–7 CYP2C19 extensive metabolizers (2C19*1/2C19*1) and 7 poor metabolizers (2C19*2/2C19*2)–were selected to participate in this study. Pharmacokinetics of oral voriconazole 200 mg after administration of Ginkgo biloba 120 mg twice daily for 12 days were determined for up to 24 hours by liquid chromatography–electrospray tandem mass spectrometry in a 2-phase randomized crossover study with 4-week washout between phases.Results:For extensive metabolizers, the median value for voriconazole area under the plasma concentration–time curve from zero to infinity (AUC0-00) was 5.17 μg•h/mL after administration of voriconazole alone and 4.28 μg•/mL after voriconazole with Ginkgo biloba (p > 0.05). The other pharmacokinetic parameters of voriconazole such as AUC0-24, time to reach maximum concentration, half-life, and apparent clearance also did not change significantly for extensive metabolizers in the presence of Ginkgo biloba. Pharmacokinetic parameters followed a similar pattern for poor metabolizers.Conclusions:The results suggest that 12 days of treatment with Ginkgo biloba did not significantly alter the single-dose pharmacokinetics of voriconazole in either CYP2C19 extensive or poor metabolizers. Therefore, the pharmacokinetic interactions between voriconazole and Ginkgo biloba may have limited clinical significance.

The authors investigated the effect of herbal medicine Schisandra chinensis extract (SchE) and Ginkgo biloba extract (GBE) on the oral pharmacokinetics of P-glycoprotein substrate talinolol in humans. Twelve healthy male volunteers took a single 100-mg oral dose of talinolol either alone or after pretreatment with 300 mg SchE twice daily or with 120 mg GBE three times daily for 14 days. On day 14, a single 100-mg oral dose of talinolol was administered. Plasma concentrations of talinolol from zero to 24 h were measured by high-performance liquid chromatography. SchE increased the area under the curve (AUC)(0-24) of talinolol by 47% (90% confidence interval (CI), 18-84%; p = 0.010), and GBE by 21% (90% CI = 11-32%; p = 0.002). The C(max) of talinolol increased by 51% (90% CI = 21-89%; p = 0.007) with SchE treatment and by 33% (90% CI = 18-51%; p = 0.002) with GBE treatment, respectively. The t(1/2) of talinolol increased by 7% (90% CI = -4% to 19%; p = 0.320) with SchE treatment and by 11% (90% CI = -12% to 38%; p = 0.436) with GBE treatment, respectively. The results suggest that both SchE and GBE significantly inhibited P-glycoprotein in humans. Patients receiving either SchE or GBE may require dose adjustments when treated with drugs primarily transported by P-glycoprotein.

Background : The renin–angiotensin system (RAS) is regarded as one of the most important regulatory systems for cardiovascular homeostasis. In this study, we investigated associations of the five genetic polymorphisms in the RAS and presence of coronary artery disease (CAD) in type 2 diabetes. Methods : Genotyping was performed by polymerase chain reaction–restriction fragment length polymorphism analysis. We used the generalised multifactor dimensionality reduction (GMDR) method to identify gene–gene interactions. Results : The D allele in the ACE gene was significantly more frequent in type 2 diabetic patients with CAD ( p = 0.04). In multivariate logistic regression analysis, the DD genotype was associated with a significantly increased risk of CAD ( p = 0.044). 1675G/A variant in the AT2R gene was found to be associated with CAD in female subjects with type 2 diabetes ( p = 0.025). The three other polymorphisms of the RAS do not seem to influence the development of CAD in type 2 diabetes. No significant gene–gene interaction for any combinations of genotypes was found in the GMDR method. Conclusion : The DD variant of the ACE gene polymorphism is associated with increased risk of developing CAD in Chinese patients with type 2 diabetes. A slight impact of AT2R 1675G/A polymorphism on CAD was found only in female diabetic patients.

Background Ginkgo biloba extract (GBE), the best selling herbal medicine in the world, has been reported to inhibit P-glycoprotein in vitro. However, the effects of GBE on P-glycoprotein activity in humans have not been clarified. Objective To investigate the effects of single and repeated GBE ingestion on the oral pharmacokinetics of talinolol, a substrate drug for P-glycoprotein in humans. Methods Ten unrelated healthy male volunteers were selected to participate in a 3-stage sequential study. Plasma concentrations of talinolol from 0 to 24 hours were measured by high-performance liquid chromatography after talinolol 100 mg was administrated alone, with a single oral dose of GBE (120 mg), and after 14 days of repeated GBE ingestion (360 mg/day). Results A single oral dose of GBE did not affect the pharmacokinetics of talinolol. Repeated ingestion of GBE increased the talinolol maximum plasma concentration (Cmax) by 36% (90% CI 10 to 68; p = 0.025), the area under the concentration-time curve (AUC)0-24 by 26% (90% CI 11 to 43; p = 0.008) and AUC0-∞ by 22% (90% CI 8 to 37; p = 0.014), respectively, without significant changes in elimination half-life and the time to Cmax. Conclusions Our results suggest that long-term use of GBE significantly influenced talinolol disposition in humans, likely by affecting the activity of P-glycoprotein and/or other drug transporters.

This study investigated the effect of the herbal medicine baicalin on bupropion hydroxylation, a probe reaction for CYP2B6 activity related to different CYP2B6 genotype groups. Seventeen healthy male volunteers (6 CYP2B6*1/*1, 6 CYP2B6*1/*6, and 5 CYP2B6*6/*6) received orally administered bupropion alone and during daily treatment with baicalin. Blood samples were taken up to 72 h after each bupropion dose, and pharmacokinetics profiles were determined on days 1 and 25 for bupropion and hydroxybupropion. Baicalin administration increased hydroxybupropion maximum plasma concentration (C max) by 73% [90% confidence interval (CI), 44–108%; P

To study the pharmacokinetic characteristics of voriconazole in healthy Chinese male volunteers in relation to cytochrome P450 (CYP) 2C19 genotype status, including ultra-rapid metabolizers (URMs), homozygous extensive metabolizers (EMs), and poor metabolizers (PMs).Twenty healthy Chinese male volunteers were recruited for the study. Of these, four were CYP2C19 heterozygous URMs (*1/*17), eight were CYP2C19 homozygous EMs (*1/*1), and eight were CYP2C19 PMs (*2/*2). After a single oral dose of 200 mg voriconazole, plasma concentrations of voriconazole were determined for a 24-h period by liquid chromatography-mass spectrometry/mass spectrometry.In Chinese male subjects, the allele frequencies of the CYP2C19*17 and CYP2C19*2 alleles were 0.64 and 35.6%, respectively, and both alleles were in Hardy-Weinberg equilibrium. The area under the concentration-time curve (AUC) from predose to 24 h (AUC(0-24)) and from predose to infinity (AUC(0-infinity)), and apparent oral clearance (CL/F) of voriconazole were statistically different among all three genotypic groups (P0.001, respectively). The maximum plasma concentration (C(max)) value of URMs also showed statistically significant differences from those of EMs and PMs (P = 0.036 and P = 0.035, respectively). The elimination half-life (t(1/2)) in URMs was 87% (P = 0.58) of that in EMs and 51% (P= 0.002) of that in PMs.Our data indicate that the presence of the CYP2C19*17 allele results in ultra-rapid metabolism of voriconazole after a single oral dose.