• Archives of Pharmacal Research
• /
• v.28 no.10
• /
• pp.1196-1202
• /
• 2005

Omeprazole (OMP) is a proton pump inhibitor used as an oral treatment for acid-related gastrointestinal disorders. In the liver, it is primarily metabolized by cytochrome P-450 (CYP450) isoenzymes such as CYP2C19 and CYP3A4. 5-Hyroxyomeprazole (5-OHOMP) and omeprazole sulfone (OMP-SFN) are the two major metabolites of OMP in human. Cimetidine (CMT) inhibits the breakdown of drugs metabolized by CYP450 and reduces, the clearance of coad-ministered drug resulted from both the CMT binding to CYP450 and the decreased hepatic blood flow due to CMT. Phenobarbital (PB) induces drug metabolism in laboratory animals and human. PB induction mainly involves mammalian CYP forms in gene families 2B and 3A. PB has been widely used as a prototype inducer for biochemical investigations of drug metabolism and the enzymes catalyzing this metabolism, as well as for genetic, pharmacological, and toxicological investigations. In order to investigate the influence of CMT and PB on the metabolite kinetics of OMP, we intravenously administered OMP (30 mg/kg) to rats intraperitoneally pretreated with normal saline (5 mL/kg), CMT (100 mg/kg) or PB (75 mg/kg) once a day for four days, and compared the pharmacokinetic parameters of OMP. The systemic clearance ($CL_{t}$) of OMP was significantly (p<0.05) decreased in CMT-pretreated rats and significantly (p<0.05) increased in PB-pretreated rats. These results indicate that CMT inhibits the OMP metabolism due to both decreased hepatic blood flow and inhibited enzyme activity of CYP2C19 and 3A4 and that PB increases the OMP metabolism due to stimulation of the liver blood flow and/or bile flow, due not to induction of the enzyme activity of CYP3A4.

• The Journal of Korean Medicine
• /
• v.38 no.2
• /
• pp.15-30
• /
• 2017

Objectives: Hwangryunhaedok-tang (HHT; Huanglianjiedu-tang, Orengedoku-to), a traditional herbal formula, is used for treating inflammation, hypertension, gastritis, liver dysfunction, cerebrovascular diseases, dermatitis and dementia. The objective of this study was to assess the sub-acute toxicity of HHT in Sprague-Dawley (SD) rats, and its effect on the activities of human microsomal cytochrome P450s (CYP450s) and UDP-glucuronosyltransferases (UGTs). Methods: Male and female SD rats were orally administered HHT once daily at doses of 0, 500, 1000 and 2000 mg/kg for 4 weeks. We analyzed mortality, clinical observations, body weight, food consumption, organ weights, urinalysis, hematology, serum biochemistry, and histopathology. The activities of major human CYP450s (CYP1A2, CYP3A4, CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP2E1) and UGTs (UGT1A1, UGT1A4, and UGT2B7) were assessed using in vitro fluorescence- and luminescence-based enzyme assays, respectively. Results: No toxicologically significant changes related to the repeated administration of HHT were observed in both male and female SD rats. The no observed adverse effect level (NOAEL) value was more than 2000 mg/kg/day for both sexes. HHT inhibited the activities of human microsomal CYP1A2, CYP2C19, CYP2D6, and CYP2E1, whereas it weakly inhibited the activities of CYP2B6, CYP2C9, CYP3A4, and UGT1A1. In addition, HHT negligibly inhibited the activities of human microsomal UGT1A4 and UGT2B7 with $IC_{50}$ values in excess of $1000{\mu}g/mL$. Conclusions: Our findings indicate that HHT may be safe for repeated administration up to 4 weeks. In addition, these findings provide information on the safety and effectiveness of HHT when co-administered with conventional drugs.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.21 no.6
• /
• pp.1415-1423
• /
• 2007

Carbon tetrachloride ($CCl_4$)-induced liver injury depends on a toxic agent that has to be metabolized by the liver NAPDH-cytochrome P450 enzyme system to a highly reactive intermediate. Alternations in the activity of cytochrome P450 enzymes affect the susceptibility to hepatic injury from $CCl_4$. In this study, we evaluated the potential protective activity of the traditional Korean medicinal herb, Corni fructus (CF), against an experimental model of hepatotoxicity induced by $CCl_4$. The CF exhibited a hepatoprotective activity against $CCl_4-induced$ liver damage in Sprague-Dawley (SD) rats, as measured by GOT, GPT, ALP and histological observation. The CF also showed significant decrease of malodialdehyde (MDA) and increase of glutathion (GSH), catalase activity in rat liver homogenate. In addition, the expression of CYP2E1, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis, was significantly decreased in the liver of CF treated SD rats. But $CCl_4$ and CF has no significant effect on 1A1 and 3A1 isoform of cytochrome P450. Based on these findings, it is suggested that hepatoprotective effects of CF possibly related to antioxidative effects and regulation of CYP2E1 expression.

• Journal of Microbiology and Biotechnology
• /
• v.33 no.3
• /
• pp.378-386
• /
• 2023

The CYP707A family genes encoding ABA 8'-hydroxylase catabolize abscisic acid (ABA), a plant stress hormone that plays an important role in stress condition, such as drought, heat, cold and salinity. Phaseic acid (PA) is a catabolic product of ABA. Recent studies have shown that PA is important for the physiological functions in plants. It is also a neuroprotective molecule that protects against ischemic brain injury in mice. To obtain enzymes for the PA production, four CaCYP707A genes (CaCYP707A1, CaCYP707A2, CaCYP707A3 and CaCYP707A4) were isolated from hot pepper. They were heterologously expressed in Escherichia coli. Among them, CaCYP707A2 showed significantly higher expression levels in both the membrane fraction and the soluble fraction. Preferred redox partners were investigated to improve the efficiency of CaCYP707A2's catalytic reaction, and NADPH-cytochrome P450 reductase (CPR) from hot pepper (CaCPR) was preferred over other redox partners (i.e., rat CPR and ferredoxin reductase/ferredoxin). The production of 8'-hydroxy ABA and PA by ABA hydroxylation activity was confirmed in CaCYP707A2 from both membrane and soluble fractions. Therefore, CaCYP707A2 is the first identified plant CYP protein that is expressed a soluble form in cytosolic fraction having stable activity. Taken together, we propose a new CYP707A protein with industrial applications for PA production without additional modifications in E. coli heterologous expression.

• Mass Spectrometry Letters
• /
• v.12 no.4
• /
• pp.172-178
• /
• 2021

HYIpro-3-1 is an adjuvant for preventing or treating inflammatory growth diseases. In this study, we identified the metabolic pathway of HYIpro-3-1 in human liver microsomes (HLMs) by quadrupole-orbitrap high-resolution mass spectrometry (HR-MS) and characterized the major human cytochrome P450 (CYP). Ten metabolites were identified, including one O-demethylation (M1), two O-demethylation and monohydroxylation (M2 and M3), and seven monohydroxylation metabolites (M4-M10). Based on the HR-MS² spectra, the metabolites are divided into two groups of monohydroxylated metabolites according to the hydroxylation position. We verified that HYIpro-3-1 is metabolized by CYP in HLMs, CYP2B6 is mainly involved in O-demethylation, and various CYPs are involved in the monohydroxylation of HYIpro-3-1.

• Korean Journal of Pharmacognosy
• /
• v.50 no.3
• /
• pp.159-164
• /
• 2019

Zanthoxylum Peel is widely used as a common spice for a variety of foods. In the orient, it has also been used as traditional agents for treating diseases such as indigestion. Recently, Zanthoxylum Peel has been reported to have anti-cancer activity, anti-microbial activity, and anti-inflammatory activity. Chemical components are known sanshool compounds and xanthoxylin. In this study, we were carried out to investigate the constituents of inhibiting a drug metabolizing enzyme CYP3A4 from Zanthoxylum Peel. CYP3A4 is known as an enzyme involved in drug metabolism as monooxygenase containing the heme. As a result of experiment, we found that bergapten ($IC_{50}=18.21{\mu}M$) and quercetin ($IC_{50}=17.27{\mu}M$) isolated from EtOAc extract of Zanthoxylum Peel showed remarkable CYP3A4-inhibiting activities. Structures of the isolated active compounds were established by chemical and spectroscopic means.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.21 no.1
• /
• pp.49-54
• /
• 2011

In order to develop the methods for exposure assessment and find susceptibility markers for the workers who are exposed to low doses of toluene, xylene and other chemical in petroleum industries, we investigated the application of P-450 expression in human lymphocytes utilizing mouse monoclonal anti-rat CYP2B1/2, the levels of toluene and xylene in air and their metabolite levels in urine with the levels of expressed CYP2B1/2 proteins. The general characteristics such as age, smoking and drinking habit were no significant difference between the control and exposed workers, but the working durations and working hours were significantly different. Workers in exposed group were exposed to the mean of 2.1 ppm (range, 0.00-4.54) of toluene and 0.3 ppm (rang, 0.00-1.23) of xylene. The mean concentration of urinary hippuric acid was low and less than 1/5 of the biological exposure index recommended by the Ministry of Employment and Labor Korea. Methyl hippuric acid in urine was not detected in control and exposed workers. Also, there were no significant differences in the levels of the urinary metabolites between the control and exposed group. When chemiluminescence dot blottings were carried out utilizing mouse monoclonal antibody against CYP2B1/2, the strong density dots corresponding to a mouse monoclonal antibody was observed in the human lymphocytes from the exposed workers. These results suggested that the chemiluminescence dot blot assay for CYP of lymphocytes should be valuable for identifying CYP expression as biomarkers in the workers exposed to toluene and xylene.

• Journal of Life Science
• /
• v.17 no.3 s.83
• /
• pp.334-339
• /
• 2007

We evaluated the potential of 20 herbal medications (HMs), commonly used in Korea, to inhibit the catalytic activities of several cytochrome P450 (CYP) isoforms. The abilities of 500 ${\mu}g/ml$ of aqueous extracts of 20 HMs to inhibit phenacetin O-deethylation (CYP1A2), coumarin 6-hydroxylation (CYP2A6), bupropion hydroxylation (CYP2B6), rosiglitazone hydroxylation (CYP2C8), tolbutamide 4-methylhydroxylation (CYP2C9), S-mephenytoin 4'-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1), and midazolam 1'-hydroxylation (CYP3A) were tested using human liver microsomes. The HMs Woohwangcheongsimwon suspension and Hwanglyeonhaedok-Tang strongly inhibited CYP2B6 and CYP2D6 isoform activity, respectively. These results suggest that some of the HMs used in Korea have potential to inhibit CYP isoforms in vitro. Although the plasma concentrations of the active constituents of the HMs were not determined, some herbs could cause clinically significant interactions because the usual doses of those individual herbs are several grams of freeze-dried extracts.

• Advances in Traditional Medicine
• /
• v.7 no.4
• /
• pp.357-362
• /
• 2007

Cytochrome P450 2C19 (CYP2C19) is a clinically important enzyme involved in the metabolism of therapeutic drugs, including (S)-mephenytoin, omeprazole, proguanil, and diazepam. Individuals are characterized as either extensive metabolizers (EM) or poor metabolizers (PM) on the basis of CYP2C19 enzyme activity. The PM phenotype occurs in 2-5% of Caucasians, but in 18-23% of Asians. To clarify the association between CYP2C19 polymorphisms and gastric cancer in Koreans, we investigated CYP2C19 genotypes ($CYP2C19^*1,\;{^*2},\;and\;^*3$) in 109 patients with gastric cancer and 211 controls. Normal ($CYP2C19^*1$) and defective alleles were detected with polymerase chain reaction/restriction enzyme analysis. CYP2C19 has three hereditary genotypes: homozygous EM, with high enzymatic activity; heterozygous EM, with moderate enzymatic activity; and PM, with no enzyme activity. We found that CYP2C19 heterozygous EM is more closely associated with gastric cancer than is homozygous EM. Because the CYP2C19 genotype varies in Koreans, a genotyping test is desirable to prevent gastropathy recurrence in patients before their doses of omeprazole are reduced during maintenance therapy.

• Proceedings of the Korea Environmental Mutagen Society Conference
• /
• 2003.10a
• /
• pp.166-166
• /
• 2003