• 한국산업보건학회지
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• 제19권1호
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• pp.73-79
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• 2009

This study was undertaken to investigate the effects of single and combined exposure of toluene (T) and xylene (X) on the cytochrome-450(CYP)-mediated metabolizing capacity, induction of CYP isozymes and the excretion of their metabolites in urine. Animal were adults male Sprague-Dawley (SD) rats and divided into 4 groups such as control, T (treated with 63.7 mg/body kg), X (treated with 65.9 mg/body kg) and TX(T=X). Organic solvents was administrated by intraperitoneal injection for 3 days. The contents of protein and CYP in liver microsomes of control group were $16.48{\pm}0.56 mg/m{\ell}$ and $0.744{\pm}0.025$ nmol/mg protein, respectively, and they contents were significantly lower than in derived from treated groups (p<0.01). The activities of PROD and ${\rho}NPH$ were significantly higher in single treated groups than in control and combined group (TX). When Western immunoblotting were carried out with two monoclonal antibodies (MAb 1-98-1 and MAb 2-66-3) which were specific against CYP2B1/2 and CYP2E1, respectively, a strong signal corresponding to CYP2B1/2 was observed in microsomes obtained from rats treated with X and TX. The color density against CYP2E1 was slightly increased in T and TX groups compared with C and X groups. The amounts of urinary hippuric acid in T single treated group was $3.29{\pm}1.97$ g/g creatinine and TX combined group was $2.91{\pm}1.76$ g/g creatinine, but was not significant. However, amount of urinary methy hippuric acid in X single treated group ($1.62{\pm}0.72$ g/g creatinine) was significantly higher than TX combined group ($0.93{\pm} 0.63$ g/g creatinine)(p<0.01). These results suggested that CYP2E1 isozyme might be responsible for the metabolism of T, and CYP2B1/2 isozyme is for X. And also, difference of metabolites level between single and combined group may be speculated that the intermediates of T and X interacted each other in the process of their metabolite formation reaction.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6505-6510
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• 2012

Background: CYP2E1 encodes an enzyme which is mainly involved in bioactivation of potential carcinogens such as N-nitrosamines. Polymorphisms in the gene have been reported to be associated with cancer. The aim of this study was to evaluate genotype distributions and allele frequencies of five CYP2E1 polymorphisms in Iran Materials and Methods: Two hundred healthy individuals of an Iranian population from the southwest were included in this study. PCR-restriction fragment length polymorphism and Tetra-ARMS PCR methods were applied for CYP2E1 genotyping. Results: The allele frequencies for $^*5B$, $^*6$, $^*7B$, $^*2$, and $^*3$ were calculated to be 1.5%, 16%, 28.5%, 0%, and 2.75% respectively. Results of this study showed that no significant differences in genotype and allele frequencies of five single nucleotide polymorphisms with respect to the gender and tribes. The chi-square test showed that the genotype frequencies of $CYP2E1^*5B$ were similar to Caucasians, but the distribution of $CYP2E1^*6$ genotypes was similar to Asians. The frequencies of $CYP2E1^*2$ (0%) and $CYP2E1^*3$ (2.75%) alleles were within the range for Caucasians and Orientals. In the case of $CYP2E1^*7B$, the data werelimited. Accordingly, the results were only compared with Europeans and the comparison showed significant differences. Conclusions: In conclusion, ethnic and geographic differences may explain discrepancies in the prevalence of CYP2E1 polymorphisms.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.112.2-112.2
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• 2003

CYP1 enzymes, CYP1A1, CYP1A2 and CYP1B1, are known to bioactivate procarcinogens particularly polyaromatic compounds. Flavonoids are a class of natural compounds that are present in edible plants. Structurally, these compounds are polyphenols with two aromatic rings (A, B) and a heterocycyclic ring (C). We observed the differential inhibition of 5,7-dihydroxyflavones which are different in numbers of B-ring-OH, to the activity of ethoxyresorufin O-deethylase (EROD) in human hepatic microsomes with the IC50 values, ie, 0.57 mM, 1.28 mM, and 3.62 mM, chrysin, apigenin, and Luteolin, respectively. (omitted)

• 한국산업보건학회지
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• 제21권1호
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• pp.49-54
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• 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.

• 한국환경성돌연변이발암원학회지
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• 제24권3호
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• pp.128-136
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• 2004

CYP1A1 is known to be inducible by xenobiotic compouds such as polyciclic aromatic hydrocarbons(PAHs) and 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). These chemicals have been identified worldwide and can have a significant impact on the human health and well being of human and wildlife. Given these issues, the detection and quantification of these chemicals in biological, environmental and food samples is important. First, we investigated the effect of on CYP1A1 promoter activity, 7-ethoxyresorufin-O-deethylase(EROD) activity and CYP1A1 mRNA expression induced by benzo(k)fluoranthene(B(k)F) in MCF-7 cells. We found that B(k)F significantly up-regulates the level of CYP1A1 prompter activity, EROD and CYP1A1 mRNA. When cells were treated with genistein, it was not changed that EROD and CYP1A1 mRNA, compared to that of control. However, genistein inhibited the B(k)F-induced CYP1A1 promoter activity and mRNA level at high concentration. Furthermore, in this study, effects of HDAC(histone deacetvlase) inhibitors on human prostate cancer cells proliferation were examined. HC-toxin, SAHA and TSA inhibited cell proliferation in PC3 cells. A novel HDAC inhibitor, IN2001 also suppressed the growth of PC3 cells. And IN2001 and SAHA increased S phase and G2/M phase at 12 hrs treatment but cells were arrested G0/G1 phase at 45 hrs treatment. The HC-toxin treatment for 24 hrs and 48 hrs increased G0/G1 at low concentration ($0.1\mu\textrm{m}$) but increased G2/M at more than concentration of $1\mu\textrm{m}$. TSA increased G2/M phase. These findings height the possbility of developing HDAC inhibitors as potential anticancer therapeutic agents for the treatment of prostate cancer.

• Archives of Pharmacal Research
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• 제27권2호
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• pp.232-238
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• 2004

Trolox is a hydrophilic analogue of vitamin E. The aim of this study was to investigate its effects on hepatic injury, especially alteration in cytochrome P450 (CYP)-dependent drug metabolism during polymicrobial sepsis. Rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP). The rats were treated intravenously with Trolox (2.5 mg/kg) or vehicle, immediately after CLP. Serum aminotransferases and lipid peroxidation levels were markedly increased 24 h after CLP. This increase was attenuated by Trolox. Total CYP content and NADPH-P450 reductase activity decreased significantly 24 h after CLP. This decrease in CYP content was attenuated by Trolox. At 24 h after CLP, there was a significant decrease in the activity of these CYP isozymes: CYP1A1, 1A2, 2B1, and 2E1. However, Trolox differentially inhibited the decrease in CYP isozyme activity. Trolox had little effect on the decrease in CYP1A1 activity but Trolox significantly attenuated decreases in CYP1A2 and 2E1 activities. In fact, Trolox restored CYP2B1 activity to the level of activity found in control rats. Our findings suggest that Trolox reduces hepatocellular damage as indicated by abnormalities in hepatic drug-metabolizing function during sepsis. Our data also indicates that this protection is, in part, caused by decreased lipid peroxidation.

• The Korean Journal of Physiology and Pharmacology
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• 제5권5호
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• pp.407-412
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• 2001

Many drugs are primarily metabolized by the cytochrome P450s (CYPs). Drug metabolites would be important allergens for adverse drug reactions such as drug eruptions. Skin tests with a suspected drug have conducted to identify causative drugs of drug eruptions, with vehicles such as white petrolatum, DMSO, ethanol. This study will compare the expression of rat CYP isozyme mRNAs between the skin and the liver, with examining an effect of the vehicles on the cutaneous CYPs using semi-quantitative RT-PCR. Thirty-two Sprague-Dawley rats between the ages of six and eight weeks were divided as four groups. One group was used to compare the constitutive mRNA expression between skin and liver, while the others were to examine the effects of three vehicles. The ratios of expression of CYP1A2, CYP2B1/2, CYP2E1, CYP3A1, and CYP4A1 were significantly higher in the liver than the skin. However, CYP1A1 and CYP2C11 were higher in the skin than liver. The effects of vehicles were quite different; white petrolatum significantly induced CYP1A1 (p=0.012) and CYP2C11 mRNAs, while ethanol inhibited CY P1A1 and CYP2B1/2. DMSO did not make any changes. The results suggest that rat skin can participate in drug metabolism with their own CYP isozymes. The effects of vehicles on the cutaneous CYP expression should not be ignored and may be applied for determination of an appropriate vehicle for certain drug(s).

• Clinical and Experimental Reproductive Medicine
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• 제33권2호
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• pp.85-95
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• 2006

목 적: CYP1B1은 자궁내막증의 발생과 관련된 에스트로겐의 대사 및 dioxin의 대사 모두와 관련이 있는 유전자로 생각하여 자궁내막증의 발생위험과 CYP1B1의 codon 119G${\rightarrow}$T, 432G${\rightarrow}$C, 449T${\rightarrow}$C, 453A${\rightarrow}$G의 유전자 다형성과의 관계에 대해서 알아보고자 하였다. 연구방법: 병리조직학적으로 자궁내막증 III기와 IV기임을 확인한 여성 199명과 대조군으로 자궁내막증 환자군과 연령이 비슷한 여성에서 양성 난소 낭종으로 수술을 시행하여 자궁내막증이 없음을 육안으로 확인한 183명을 대상으로 PCR 및 RFLP를 시행하여 CYP1B1의 codon 119G${\rightarrow}$T, 432C${\rightarrow}$G, 449T${\rightarrow}$C, 453A${\rightarrow}$G의 다형성을 조사하였다. 결 과: CYP1B1에서 $Ala^{l19}Ser$, $Va1^{432}Leu$, $Asn^{449}(T^{449}{\rightarrow}C)$, $Asn^{453}Ser$ 각각의 유전자 다형성은 그 분포와 위험도에 있어서 자궁내막증 환자와 대조군 간에 통계적으로 유의한 차이는 없었다. CYP1B1에서 앞서 밝힌 4가지 codon의 다형성을 조합한 결과 GG/CC/CC/AA의 유전자형을 갖는 여성에 비해 GG/GC+GG/TC+TT/AA의 유전자형을 갖는 경우만이 자궁내막증의 위험도가 2.056 (95% CI: 1.003-4.216)으로 유의하게 높은 것을 알 수 있었다. 결 론: 이상으로 볼 때 한국인 여성에서 중증자궁내막증 발생은 CYP1B1의 유전적 다형성과 관련이 있는 것으로 보이며, 향후 자궁내막증의 발생 기전을 밝히는데 주요한 자료가 될 것으로 본다.

• 대한한의학회지
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• 제38권2호
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• pp.15-30
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• 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.

• Clinical and Experimental Reproductive Medicine
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• 제48권4호
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• pp.347-351
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• 2021

Objective: We investigated the impact of vitamin D₃ (VD3) supplementation during mouse preantral follicle culture in vitro and the mRNA expression of 25-hydroxylase (CYP2R1), 1-alpha-hydroxylase (CYP27B1), and vitamin D receptor (VDR) in mouse ovarian follicles at different stages. Methods: Preantral follicles were retrieved from 39 BDF1 mice (7-8 weeks old) and then cultured in vitro for 12 days under VD3 supplementation (0, 25, and 50 pg/mL). Follicular development and the final oocyte acquisition were assessed. Preantral follicles were retrieved from 15 other BDF1 mice (7-8 weeks old) and cultured without VD3 supplementation. Three stages of mouse ovarian follicles were obtained (preantral, antral, and ruptured follicles). Total RNA was extracted from the pooled cells (from 20 follicles at each stage), and then reverse transcriptase-polymerase chain reaction was performed to identify mRNA for CYP2R1, CYP27B1, and VDR. Results: The survival of preantral follicles, rates of antrum formation and ruptured follicles (per initiated follicle) and the number of total or mature oocytes were all comparable among the three groups. Both CYP2R1 and CYP27B1 were expressed in antral and ruptured follicles, but not in preantral follicles. VDR was expressed in all three follicular stages. Conclusion: VD3 supplementation in vitro (25 or 50 pg/mL) did not enhance mouse follicular development or final oocyte acquisition. Follicular stage-specific expression of CYP2R1, CYP27B1, and VDR was observed.