The fields of pharmacogenetics and pharmacogenomics have become increasingly promising regarding the clinical application of genetic data to aid in prevention of adverse reactions. Specific screening tests can predict which animals express modified proteins or genetic sequences responsible for adverse effects associated with a drug. Among the genetic variations that have been investigated in dogs, the multidrug resistance gene (MDR) is the best studied. However, other genes such as CYP1A2 and CYP2B11 control the protein syntheses involved in the metabolism of many drugs. In the present study, the MDR-1, CYP1A2 and CYP2B11 genes were examined to identify SNP polymorphisms associated with these genes in the following four canine breeds: Uruguayan Cimarron, Border Collie, Labrador Retriever and German Shepherd. The results revealed that several SNPs of the CYP1A2 and CYP2B11 genes are potential targets for drug sensitivity investigations.
Animals ; Aryl Hydrocarbon Hydroxylases/*genetics/metabolism ; Cytochrome P-450 CYP1A2/*genetics/metabolism ; Dogs/*genetics/metabolism ; P-Glycoprotein/*genetics/metabolism ; *Polymorphism, Single Nucleotide ; Steroid Hydroxylases/*genetics/metabolism

Alleles ; Animals ; Aryl Hydrocarbon Hydroxylases ; genetics ; metabolism ; Cytochrome P-450 CYP2A6 ; Humans ; Mixed Function Oxygenases ; genetics ; metabolism ; Nicotine ; metabolism ; Polymorphism, Genetic ; Tobacco Use Disorder ; metabolism

E2 is a recombinant hepatitis E virus capsid protein including its main antigenic determinants but lacking of the particle assembling domain. P239 was the C-terminal extending protein of E2 and could self-assemble to form virus like particles, which might serve as mimicry of virions both structurally and antigenically. We previously used yeast two-hybrid system to screen proteins interacting with E2 based on a human hepatocyte cDNA library. One candidate was identified as the segment (aa388-437) of cytochrome P450 2A6 protein, which is predominantly expressed in liver and important for metabolization. Some studies have demonstrated that hepatitis virus infection may altered cell metabolic clearance of coumrarin which were rapidly matebolised by CYP2A6. In this research, we demonstrated that the protein interaction between HEV capsid proteins and CYP2A6 by pull-down and co-immunoprecipitation. It was also found that their interaction could decrease the CYP2A6 catalytic activity when p239 was incubated within the CYP2A6-transfected Huh7 cells. These results suggested that CYP2A6 might be related to the pathological process when HEV invaded host cells.
Aryl Hydrocarbon Hydroxylases ; genetics ; metabolism ; Capsid Proteins ; genetics ; metabolism ; Cell Line, Tumor ; Coumarins ; metabolism ; Cytochrome P-450 CYP2A6 ; Hepatitis E virus ; metabolism ; Humans ; Imidazoles ; metabolism ; Immunoprecipitation ; Protein Binding ; Recombinant Proteins ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo detect the single nucleotide polymorphisms of clopidogrel metabolism related genes (CYP2C19, ABCB1 and PON1) in Chinese patients with acute coronary syndrome (ACS) by genotype analysis.

METHODSGenetic analysis was performed in patients admitted to Fuwai Hospital from 2005 to 2008 with ACS within 4 weeks. The detection of polymorphisms was performed by TaqMan real-time PCR method. The alleles genotyped were CYP2C19 *2-*8, *17, ABCB1 C3435T, PON1 Q192R and PON1 L55M. Minor allele frequency (MAF) was calculated. Patients were classified as one of the 5 categories by clopidogrel metabolizer phenotypes as extensive [without any "loss-of-function" (LOF) allele *2-*8 or "gain-of-function" (GOF) allele *17], intermediate (with only one LOF allele), Poor (with two or more LOF alleles), ultra (with one or two GOF alleles) or unknown (with one LOF allele and one GOF allele).

RESULTSA total of 2800 ACS patients were enrolled [mean age (59.0 ± 12.3) years and 2236 males (79.9%)]. There were 74% patients with ST-segment elevation myocardial infarction (STEMI, n = 2072), 22.0% patients with non-ST-segment elevation myocardial infarction (NSTEMI, n = 617) and 4.0% patients with unstable angina (UA, n = 111). The minor allele frequency (MAF) for each genotype of CYP2C19 *2, *3, *4, *17 was 28.7%, 4.6%, 0.1% and 1.2%, respectively. There was no LOF allele *5-*8 in the study population. The MAF for ABCB1 C3435T, PON1 Q192R and PON1 L55M was 39.4%, 37.8% and 4.4%, respectively. Clopidogrel metabolizer groups were defined as extensive in 41.7%, intermediate in 45.6%, poor in 10.3%, ultra in 1.9% and unknown in 0.6% patients, respectively. There were no significant differences for all genotypes between males and females. Total LOF carriers of CYP2C19 were 56.4% and GOF carriers were 2.5%.

CONCLUSIONSOur study demonstrated a high distribution of the LOF allele of CYP2C19 in China ACS population.

Acute Coronary Syndrome ; genetics ; metabolism ; Aged ; Alleles ; Aryl Hydrocarbon Hydroxylases ; genetics ; Aryldialkylphosphatase ; genetics ; Asian Continental Ancestry Group ; genetics ; Cytochrome P-450 CYP2C19 ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; Ticlopidine ; analogs & derivatives ; metabolism

In this study, we successfully expanded a full length gene encoding the monooxygenase eytochrome P450 2C9 gene from human liver of Chinese Han by RT-PCR. Our findings indicated that except G-->T mutation at the 190th nucleotide site, the other nucleotide sequences are completely consistent with CYP2C9 (NM017460) in GenBank. The SDS-PAGE and Western-Blot analysis showed that the CYP 2C9 gene was successfully expressed in the host cell E. coli BL21 (DE3). Our current study lays the foundation for the evaluation of pre-clinical drug metabolism and safety in the future.
Aryl Hydrocarbon Hydroxylases ; biosynthesis ; genetics ; China ; ethnology ; Cloning, Molecular ; Cytochrome P-450 CYP2C9 ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; genetics ; Humans ; Point Mutation ; Polymorphism, Genetic ; Recombinant Proteins ; biosynthesis ; genetics

PURPOSE: Clopidogrel is a prodrug that requires transformation into an active metabolite by cytochrome P450 (CYP) in the liver in order to irreversibly inhibit the P2Y12 adenosine diphosphate platelet receptor. CYP2C19 polymorphism has been reported to correlate with reduced antiplatelet activity of clopidogrel in coronary artery disease. We assessed the association between CYP2C19 polymorphism and clopidogrel resistance in patients with cerebrovascular disease. MATERIALS AND METHODS: We retrospectively gathered data from patients who experienced cerebrovascular disease, received clopidogrel, and were tested for clopidogrel resistance and CYP2C19 polymorphism. Clopidogrel resistance was tested by the VerifyNow P2Y12 system, and the CYP2C19 polymorphism was tested by the Seeplex CYP2C19 ACE Genotyping system. Clopidogrel resistance was expressed in P2Y12 reaction units (PRU) and percent inhibition. High PRU and low percent inhibition suggests clopidogrel resistance. CYP2C19 polymorphisms were expressed as extensive, intermediate, and poor metabolizers. Clopidogrel resistance was assessed according to the subgroup of CYP2C19 polymorphism. RESULTS: A total of 166 patients were evaluated. The PRU values of extensive CYP2C19 metabolizers (195.0+/-84.9) were significantly lower than those of intermediate and poor metabolizers (237.9+/-88.0, 302.2+/-58.9). The percent inhibition of extensive metabolizers (44.6+/-21.8) was significantly higher than that of intermediate and poor metabolizers (30.5+/-21.5, 14.0+/-13.4). CONCLUSION: Intermediate and poor metabolizing CYP2C19 polymorphism is associated with reduced clopidogrel antiplatelet activity in patients with cerebrovascular disease. The clinical implications of this finding require further investigation.
Aged ; Aryl Hydrocarbon Hydroxylases/*genetics/metabolism ; Cerebrovascular Disorders/*drug therapy/*enzymology/genetics ; Drug Resistance/genetics ; Female ; Humans ; Male ; Middle Aged ; Platelet Aggregation Inhibitors/pharmacokinetics/*therapeutic use ; Polymorphism, Single Nucleotide ; Retrospective Studies ; Ticlopidine/*analogs & derivatives/pharmacokinetics/therapeutic use

We report a case of intolerance to warfarin dosing due to impaired drug metabolism in a patient heterozygous for the CYP2C9*3 allele. A 30-year-old woman with an artificial cardiac pacemaker was taking warfarin to prevent thromboembolism. This patient had an extremely elevated international normalized ratio (INR) of prothrombin time (PT) following standard doses of warfarin and experienced difficulties during the induction of anticoagulation. Genotyping for CYP2C9 revealed that this patient was an intermediate metabolizer with genotype CYP2C9*1/*3. This case suggests the clinical usefulness of pharmacogenetic testing for individualized dosage adjustments of warfarin.
Warfarin/administration & dosage/*adverse effects/metabolism ; Prothrombin Time ; Polymorphism, Genetic ; Humans ; Female ; Dose-Response Relationship, Drug ; DNA Mutational Analysis ; Aryl Hydrocarbon Hydroxylases/*genetics/metabolism ; Anticoagulants/administration & dosage/*adverse effects/metabolism ; Adult

OBJECTIVETo investigate the impact of omeprazole on platelet response to clopidogrel and the effect of polymorphisms of CYP2C19 on the antiplatelet effect of clopidogrel.

METHODSPlatelet aggregation (PA) was assessed before 300 mg aspirin plus 300 mg loading dose of clopidogrel and after 300 mg aspirin plus 75 mg maintenance dose of clopidogrel 7 days later in 414 patients with acute coronary syndrome who have undergone percutaneous coronary intervention (PCI). Thereafter, gastric mucosal protective drugs were given (omeprazolem 20 mg, n=224 or cimetidine 800 mg, n=190). Fourteen days later, PA was measured again. Genotypes of CYP2C19*2 were analyzed with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTSAfter taken aspirin and clopidogrel, PA has decreased significantly in both groups. Compared with cimetidine, omeprazole had no significant impact on PA on 7 and 21 days post PCI. Compared with homozygotes or heterozygotes for the wild-type CYP2C19*2, patients with CYP2C19*2 AA genotype had significantly higher PA on 7 and 21 days post PCI (P<0.05).

CONCLUSIONNo attenuating effect on platelet response to clopidogrel has been observed for Omeprazole. The variant of CYP2C19*2 AA genotype is significantly associated with attenuated response to clopidogrel.

Adult ; Aged ; Aryl Hydrocarbon Hydroxylases ; genetics ; metabolism ; Cytochrome P-450 CYP2C19 ; Drug Interactions ; Female ; Humans ; Male ; Middle Aged ; Omeprazole ; pharmacology ; Platelet Aggregation Inhibitors ; pharmacology ; Proton Pump Inhibitors ; pharmacology ; Ticlopidine ; analogs & derivatives ; pharmacology

OBJECTIVETo investigate the frequency of CYP2C19 polymorphisms involved in clopidogrel metabolism in Fujian Han population.

METHODSFrequencies of CYP2C19* 2, CYP2C19*3 and CYP2C19*17 in 1001 unrelated Fujian Han volunteers were determined with polymerase chain reaction-restriction fragment length polymorphism and direct sequencing method.

RESULTSThe frequencies of CYP2C19*2, *3 and *17 were 32.4%, 5.8% and 0.4%, respectively. According to genotyping results, intermediate metabolizers (CYP2C19 *1/*2 or *1/*3) and poor metabolizers (CYP2C19 *2/*2 and *2/*3) respectively accounted for 47.95% and 13.99% of all subjects. Above frequencies were similar to those of Japan, Korea, Singapore, Malaysia, Thailand and Chinese Dai, Mongolian,Li and Hui ethnics (P>0.05), but were significantly different from those of Chinese Kazakh and Uygur ethnics, and people from Iran, Russia, Italy, Poland, Norway, Canada native Indians, Bolivia, Egypt or Tanzania (P<0.05).

CONCLUSIONEthnic/regional diversity exist with regard to the prevalence of CYP2C19 polymorphisms. No significant difference were found between Fujian Han Chinese and Dai, Mongolian, Li and Hui from China or other populations from East and Southeast Asia, but higher frequencies of intermediate metabolizers and poor metabolizers compared with populations of Kazakh and Uygur in China, and people from Europe, South America and Africa.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Aryl Hydrocarbon Hydroxylases ; genetics ; China ; Cytochrome P-450 CYP2C19 ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Middle Aged ; Polymorphism, Genetic ; Ticlopidine ; analogs & derivatives ; metabolism ; Young Adult

OBJECTIVETo examine the expression of cytochrome P450 related genes in oral submucous fibrosis tissue and to investigate the possible role of the genes in pathogenesis of oral submucous fibrosis (OSF).

METHODSBuccul mucosa tissues were obtained from OSF patients in early, medium and advanced stages, with each stage including 10 patients. Normal buccul mucosa tissues were collected from 10 patients undergoing oral and maxillofacial surgery as control. Oral submucous fibrosis-related genes were analysed by cDNA chips, and the results were submitted to the gene network database. Differentially expressed genes related to the pathway of CYP metabolism were indentifyed by the database analysis. Reverse transcription-polymerase chain reaction (RT-PCR) was used to verify the results from cDNA chips by increasing sample volume.

RESULTSThere were eight genes [CYP2B6, CYP2C18, CYP2F1, CYP3A5, microsomal glutathione S-transferase 2 (MGST2), alcohol dehydrogenase (ADH), UDP glucuronosyl transferase 2B15 (UGT2B15), ADH1C] which were related to the pathway of CYP metabolism. These genes were low expressed in all stages of OSF (P < 0.001).There were no differences in genes expression among the three stages of OSF (P > 0.05).

CONCLUSIONSThere were down-regulated genes related to the pathway of CYP metabolism in oral submucous fibrosis tissue. The ability of the pathway of CYP to metabolize and clear betel nut ingredients was reduced in OSF patients, which may play a role in the pathogenesis of OSF.

Adult ; Alcohol Dehydrogenase ; genetics ; metabolism ; Aryl Hydrocarbon Hydroxylases ; genetics ; metabolism ; Cytochrome P-450 CYP2B6 ; Cytochrome P-450 CYP3A ; genetics ; metabolism ; Cytochrome P-450 Enzyme System ; genetics ; metabolism ; Cytochrome P450 Family 2 ; Down-Regulation ; Glucuronosyltransferase ; genetics ; metabolism ; Glutathione Transferase ; genetics ; metabolism ; Humans ; Male ; Oligonucleotide Array Sequence Analysis ; Oral Submucous Fibrosis ; metabolism ; pathology ; RNA, Messenger ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Young Adult