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This study was designed to investigate effects of pargyline on histone methylation in the promoter and enhancer regions and transcription of cytochrome P450 3A4/3A7 (CYP3A4/3A7) gene. Human primary fetal liver cells were isolated, cultured and randomly divided into several groups including control, solvent, pargyline low, middle, high dose (treated with 0.6, 1.2, 2.4 mmol·L(−1)). HepG2 cells were cultured and treated with 0.03, 0.3, 3 mmol·L(−1) pargyline. After 48 hours, total RNAs were prepared from the cells to determine the expression of CYP3A m RNA in primary fetal cells and HepG2 cells with real-time quantative PCR (qPCR). HepG2 cells were cultured and then treated with 3 mmol·L(−1) pargyline for 48 hours. The chromatin immunoprecipitation (ChIP) assay was performed with dimethylation of histone H3 at lysine 4 (H3K4me2), and IgG antibodies respectively. The precipitated DNA was resuspended and used for qPCR. Primers were used to detect different regions of CYP3A4/3A7 promoter and enhancer. Occupancy of H3K4me2 was shown as percent of input DNA relative to control cells. The results suggested that pargyline has an effect on primary fetal liver cells and HepG2 cells proliferation. The level of CYP3A7 was markedly enhanced in human primary fetal liver cells by treatment with 1.2, 2.4 mmol·L(−1) of pargyline (P < 0.05, P < 0.01) and the levels of CYP3A4/3A7 were remarkably enhanced by treatment with 3 mmol·L(−1) of pargyline in HepG2 cells (P < 0.001) compared with solvent control. Occupancy of H3K4me2 on human CYP3A4 promoter (−362 to +53) and enhancer segment (−7 836 to −6 093) harbored the overlapping hepatocyte nuclear factors 4A (HNF4A) binding site compared with a negative control. Occupancy of H3K4me2 on human CYP3A7 promoter (−163 to +103) and enhancer segment (−4 054 to −3 421, −6 265 to −6 247) overlapped with glucocorticoid receptor (GR) binding site. In conclusion, the enriched H3K4me2 in the promoter and enhancer regions was induced by pargyline with HNF4A or GR binding site in CYP3A4/3A7 gene to activate the corresponding genes.

CYP3A4 and CYP3A7 are generally served as the major adult and fetal liver forms, respectively, and exhibited a developmental switch during liver maturation. The objective of this study was to explore the potential mechanisms associated with the developmental switch of CYP3A4 and CYP3A7 in the Chinese Han population. We analyzed CYP3A4/7, nuclear receptors, and epigenetic modifications in human liver samples. We found that the expression levels of CYP3A4 mRNA in adults were significantly higher than the levels in fetus. In contrast, CYP3A7 mRNA expression reached a maximal level at an estimated gestational age of 25 weeks and then substantially decreased during the first year after birth. We also found that the expression level of hepatocyte nuclear factor 4 alpha (HNF4A) was most associated with CYP3A4 expression in adult liver; whereas the expression level of glucocorticoid receptor (GR) was intensively correlated with CYP3A7 expression in fetal liver. Furthermore, we illustrated the dynamic changes of H3K4me2 and H3K27me3 in the developmental switch of CYP3A7 and CYP3A4. In summary, our data suggested that HNF4A and GR, and epigenetic changes of H3K4me2 and H3K27me3 are associated with the ontogenic expressions of CYP3A4/3A7 in the livers of the Chinese Han population., (Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.)

Background and Objective: The polymorphic enzyme P450 oxidoreductase (POR) transfers electrons from nicotinamide adenine dinucleotide phosphate (NADPH) to cytochrome P450 (CYP) 3A enzyme s, which metabolize atorvastatin. This suggests that variations in the CYP3A5 and POR genes may influence the response to statins. We aimed to investigate the association and interactions between CYP3A5*3 and POR*28 polymorphisms and the lipid-lowering effects of atorvastatin in a Chinese population., Methods: Genotypes were determined by polymerase chain reaction (PCR) with restriction fragment length polymorphism analysis and by PCR with direct sequencing analysis for 179 hyperlipidaemic patients treated with atorvastatin 20 mg once daily for 4 weeks. Serum levels of triglycerides (TGs), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were determined before and after treatment., Results: For the 179 patients (including 100 males), the variant allele frequencies of CYP3A5*3 and POR*28 were 73.75 and 41.62 %, respectively. Among all patients, no significant association was found between CYP3A5*3 polymorphisms and TG, TC, LDL-C and HDL-C levels before and after treatment with 20 mg of atorvastatin daily for 4 weeks. Homozygotes for the POR*28 T allele showed a significantly lower mean concentration of LDL-C than homozygotes for the POR*28 C allele (POR*28 TT vs POR*28 CC: 2.46 ± 0.37 vs 2.69 ± 0.49 mmol/L, P = 0.019) after treatment with atorvastatin 20 mg daily for 4 weeks. After adjustment for age, sex and body mass index, CYP3A5 non-expressors who were POR*28 wild-type homozygotes showed significantly higher mean TC and LDL-C levels than those who were POR*28 variant homozygotes, both at baseline (*3/CC vs *3/TT; TC: 7.30 ± 0.73 vs 6.94 ± 0.36 mmol/L, P = 0.026; LDL-C: 3.88 ± 0.70 vs 3.47 ± 0.46 mmol/L, P = 0.009) and after atorvastatin treatment (*3/CC vs *3/TT; TC: 6.03 ± 0.64 vs 5.69 ± 0.34 mmol/L, P = 0.017; LDL-C: 2.80 ± 0.62 vs 2.43 ± 0.40 mmol/L, P = 0.008). CYP3A5 non-expressors who were POR*28 wild-type homozygotes showed significantly higher TC and LDL-C levels at baseline (*3/CC vs *1/CC; TC: 7.30 ± 0.73 vs 6.95 ± 0.41 mmol/L, P = 0.010; LDL-C: 3.88 ± 0.70 vs 3.55 ± 0.39 mmol/L, P = 0.010) and showed higher TC levels after atorvastatin treatment (*3/CC vs *1/CC; 6.03 ± 0.64 vs 5.73 ± 0.27 mmol/L, P = 0.012), in comparison with patients expressing CYP3A5 who were POR*28 wild-type homozygotes. CYP3A5 non-expressors who were POR*28 heterozygotes showed significantly lower percentage changes in TC from baseline than those expressing CYP3A5 who were POR*28 heterozygotes (*3/CT vs *1/CT; 16.77 ± 3.13 vs 18.40 ± 4.16 mmol/L, P = 0.031)., Conclusion: POR*28 is associated with a poorer response to atorvastatin, but there is no association of the latter with CYP3A5*3. POR*28 single nucleotide polymorphisms are associated with greater increases in the effect on plasma lipids in non-expressors of CYP3A5. Besides CYP3A5*3 genetic polymorphism, POR*28 genetic polymorphism might also be responsible for the marked interindividual variability in the lipid-lowering response to atorvastatin.

Objective: Nifedipine is a calcium channel blocker that is widely used in the treatment of cardiovascular disease. However, significant individual variances in the disposition of nifedipine have been reported, and genetic factors are considered to play an important role. The aim of the present study was to investigate the effect of CYP3A4*1G, CYP3A5*3, ABCB1-C3435T, and POR*28 genetic polymorphisms on nifedipine pharmacokinetics in healthy Chinese volunteers., Methods: 45 healthy Chinese volunteers enrolled in this study received a single oral dose of 90 mg nifedipine after providing written informed consent. Volunteers were genotyped for CYP3A4*1G, CYP3A5*3, POR*28, and ABCB1-C3435T. The blood concentrations of nifedipine were determined by high performance liquid chromatography tandem mass spectrometry (LC-MS/MS) method., Results and Discussion: There were significant differences of AUC00-∞ and AUC0-48h in the different CYP3A5*3 genotype groups (p = 0.043 and p = 0.048, respectively). The CYP3A5*3 GG group and POR*28 CT/TT group were found to have lower AUC00-∞ and Cmax compared with the POR*28 CC group (p = 0.046 and p = 0.002, respectively). In addition, the POR*28 CT/TT group was found to have longer t1/2 but lower Cmax than the CYP3A4*1G GG group (p = 0.032 and p = 0.002, respectively) as well as the CYP3A4*1G GG and the CYP3A5*3 GG group (p = 0.038 and p = 0.036, respectively) compared with the POR*28 CC group. No significant associations were found between CYP3A4*1G/ABCB1-C3435T polymorphism and pharmacokinetics of nifedipine., Conclusion: Both CYP3A5*3 and POR*28 polymorphisms are found to be associated with the difference in disposition of nifedipine; POR*28 is considered to have an impact on CYP3A4 activity.

Purpose: This study aimed to investigate whether CYP3A4*1G genetic polymorphism influences the metabolism of fentanyl in human liver microsomes in Chinese patients., Methods: The human liver microsomes were obtained from 88 hepatobiliary surgery patients who accepted liver resection surgery in this study. A normal liver sample (confirmed by the Department of Pathology) was taken from the outer edge of the resected tissue. The metabolism of fentanyl in human liver microsomes was studied. The concentration of fentanyl was measured by high performance liquid chromatography. The CYP3A4*1G variant allele was genotyped using the PCR restriction fragment length polymorphism method., Results: The frequency of the CYP3A4*1G variant allele was 0.188 in the 88 Chinese patients who had received hepatobiliary surgery. The metabolic rate of fentanyl in patients homozygous for the *1G/*1G variant (0.85 ± 0.37) was significantly lower than that in patients bearing the wild-type allele *1/*1 (1.89 ± 0.58) or in patients heterozygous for the *1/*1G variant (1.82 ± 0.65; p < 0.05). There were no gender-related differences in the metabolic rate of fentanyl (p > 0.05) nor was there any correlation between age and metabolic rate of fentanyl (p > 0.05). Results from different hepatobiliary diseases showed no significant difference in the metabolic rate of fentanyl (p > 0.05). The difference of CYP3A4 mRNA among different CYP3A4*1G variant alleles was significant (p < 0.05). There was positive correlation between CYP3A4 mRNA and metabolic rate of fentanyl (p < 0.01)., Conclusions: CYP3A4*1G genetic polymorphism decreases the metabolism of fentanyl. There is a positive correlation between CYP3A4 mRNA level and metabolism of fentanyl., (© 2015 S. Karger AG, Basel.)

Background and Objective: Fentanyl is metabolised by cytochrome P450 (CYP) 3A4 and CYP3A5. Our previous work demonstrated that the CYP3A4*1G polymorphism significantly affects the post-operative fentanyl analgesic effect in Chinese women undergoing gynaecological surgery. However, whether CYP3A5*3, a frequent single nucleotide polymorphism of CYP3A5 in Chinese people, affects the post-operative analgesic effect of fentanyl is unclear. In this study, we assessed the influence of the CYP3A5*3 polymorphism and the interaction of the CYP3A5*3 and CYP3A4*1G polymorphisms on post-operative fentanyl analgesia in Chinese women undergoing gynaecological surgery., Methods: We enrolled 203 women scheduled for abdominal total hysterectomy or myomectomy under general anaesthesia. Intravenous fentanyl patient-controlled analgesia was provided post-operatively for adequate analgesia. Pain scores and fentanyl consumption were recorded 24 h post-operatively. Midazolam was used as a probe drug, and CYP3A activity was measured by plasma ratio of 1'-hydroxymidazolam to midazolam 1 h after intravenous administration of 0.1 mg kg-1 midazolam. Blood samples were genotyped for the CYP3A5*3 polymorphism., Results: The frequency of the CYP3A5*3 allele was 72.4% in 203 patients. CYP3A activity did not differ among CYP3A5*3 genotypes. Fentanyl consumption 24 h post-operatively was lower with CYP3A5*1/*3 and CYP3A5*3/*3 polymorphisms than with CYP3A5*1/*1, but the differences were not statistically significant. However, combined with CYP3A4*1G polymorphism, post-operative fentanyl consumption at 24 h was significantly lower for the CYP3A5*1/*3 or CYP3A5*3/*3 group than the CYP3A5*1/*1 group., Conclusion: CYP3A5*3 is not the main genetic factor contributing to interindividual variation in the post-operative analgesic effect of fentanyl in Chinese women undergoing gynaecological surgery; an interaction between CYP3A5*3 and CYP3A4*1G polymorphisms can significantly influence the post-operative effect.

Response to statin therapy for cardiovascular disease is variable among different individuals. The authors aimed to investigate the effect of the CYP3AP1*3 polymorphism on the lipid-lowering efficacy of statins. They recruited 379 unrelated hyperlipidemic patients: 202 (103 men) treated with simvastatin and 177 (87 men) with atorvastatin as single-agent therapy (20 mg day(-1) orally) for 4 weeks. CYP3AP1*3(-44G>A) was genotyped using the PCR restriction fragment-length polymorphism method. Serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TGs) were determined before and after treatment. The frequency of the CYP3AP1*3 variant allele in Chinese hyperlipidemic patients was 70.6%. In the simvastatin treatment group, the percentage reduction of LDL-C level was greater in the CYP3AP1*3/*3 carriers than in the CYP3AP1*1 carriers. This difference was statistically significant for women but not for men. In contrast, the authors found no significant association between the lipid-lowering efficacy of atorvastatin and the CYP3AP1*3 polymorphism in all participants. However, in women, the percentage change of the TC level was significantly lower in the CYP3AP1*3/*3 carriers than in the CYP3AP1*1 carriers. These findings suggest that the CYP3AP1*3 allele may be a biomarker for the lipid-lowering efficacy of simvastatin and atorvastatin in Chinese women with hyperlipidemia.

Purpose: To investigate whether the CYP3A4*1G genetic polymorphism contributes to the variability in CYP3A activity and response to fentanyl., Methods: One hundred and forty-three gynecologic patients who were scheduled to undergo abdominal total hysterectomy or myomectomy with general anesthesia were enrolled in this study. Intravenous fentanyl patient-controlled analgesia was provided postoperatively for satisfactory analgesia. The degrees of pain at rest during PCA treatment were assessed with visual analog scale. The fentanyl consumption and occurrence of any adverse effects were recorded in the first 24 h postoperatively. CYP3A activity was measured by plasma 1'-hydroxymidazolam-to-midazolam ratio 1 h after intravenous administration of 0.1 mg/kg midazolam. CYP3A4*1G variant allele was genotyped using the polymerase chain reaction-restriction fragment length polymorphism method., Results: The frequency of the CYP3A4*1G variant allele was 0.269 in 143 Chinese gynecologic patients. The activity of CYP3A4 in patients homozygous for the *1G/*1G variant (0.34 +/- 0.15) was significantly lower than that in patients bearing the wild-type allele (*1/*1) (0.46 +/- 0.14) or in patients heterozygous for the *1/*1G variant (0.46 +/- 0.12) (P < 0.05). The patients with the CYP3A4*1G/*1G genotype needed less fentanyl (227.8 +/- 55.2 microg) to achieve pain control than patients carrying the CYP3A4*1/*1 (381.6 +/- 163.6 microg) and CYP3A4*1/*1G (371.9 +/- 180.1 microg) genotypes (P < 0.05) during the first 24 h postoperatively. There was no significant difference in incidence of adverse events among the different genotype groups (P > 0.05)., Conclusions: CYP3A4*1G genetic polymorphism decreases CYP3A activity and fentanyl consumption for postoperative pain control.

Purpose: Our aim was to observe the impact of CYP3A4*1G genetic polymorphism on lipid-lowering efficacy of statins., Methods: We studied 217 unrelated hyperlipidemic patients who prospectively received atorvastatin and 199 patients who received simvastatin as a single-agent therapy (20 mg day(-1) p.o.) for 4 weeks. Genotyping of CYP3A4*1G was conducted by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were determined before and after treatment by enzymatic assays., Results: The frequency of CYP3A4*1G in Chinese hyperlipidemic patients was 0.276. After atorvastatin treatment, the mean percentage reduction in serum TC was 16.8 +/- 3.3% (*1/*1), 17.8 +/- 3.8% (*1/*1G), and 20.9 +/- 5.0% (*1G/*1G), respectively. The CYP3A4*1G polymorphism had a gene-dose-dependent effect on percentage reduction in serum TC (P < 0.01). Conversely, there was no significant association between lipid-lowering efficacy of simvastatin and CYP3A4*1G polymorphism., Conclusions: Carrying CYP3A4*1G increase the lipid-lowering efficacy of atorvastatin and may have no significant effect on simvastatin treatment.