• Toxicological Research
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• 제33권3호
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• pp.211-218
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• 2017

Cytochrome P450 1B1 (CYP1B1) acts as a hydroxylase for estrogen and activates potential carcinogens. Moreover, its expression in tumor tissues is much higher than that in normal tissues. Despite this association between CYP1B1 and cancer, the detailed molecular mechanism of CYP1B1 on cancer progression in HeLa cells remains unknown. Previous reports indicated that the mRNA expression level of Herc5, an E3 ligase for ISGylation, is promoted by CYP1B1 suppression using specific small interfering RNA, and that ISGylation may be involved in ubiquitination related to ${\beta}-catenin$ degradation. With this background, we investigated the relationships among CYP1B1, Herc5, and ${\beta}-catenin$. RT-PCR and western blot analyses showed that CYP1B1 overexpression induced and CYP1B1 inhibition reduced, respectively, the expression of $Wnt/{\beta}-catenin$ signaling target genes including ${\beta}-catenin$ and cyclin D1. Moreover, HeLa cells were treated with the CYP1B1 inducer $7,12-dimethylbenz[{\alpha}]anthracene$ (DMBA) or the CYP1B1 specific inhibitor, tetramethoxystilbene (TMS) and consequently DMBA increased and TMS decreased ${\beta}-catenin$ and cyclin D1 expression, respectively. To determine the correlation between CYP1B1 expression and ISGylation, the expression of ISG15, a ubiquitin-like protein, was detected following CYP1B1 regulation, which revealed that CYP1B1 may inhibit ISGylation through suppression of ISG15 expression. In addition, the mRNA and protein expression levels of Herc5 were strongly suppressed by CYP1B1. Finally, an immunoprecipitation assay revealed a direct physical interaction between Herc5 and ${\beta}-catenin$ in HeLa cells. In conclusion, these data suggest that CYP1B1 may activate $Wnt/{\beta}-catenin$ signaling through stabilization of ${\beta}-catenin$ protein from Herc5-mediated ISGylation for proteosomal degradation.

• 한국해양생명과학회지
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• 제8권2호
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• pp.104-114
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• 2023

플라스틱은 전세계적으로 사용량이 증가함에 따라 해양 환경으로 유입되는 플라스틱 쓰레기의 양도 꾸준히 증가하고 있으며, 미세플라스틱은 해양 생물에 의해 섭취되어 소화관에 축적됨에 따라 성장과 생식에 유해한 영향을 미친다. Cytochrome P450 (CYP)는 환경 오염물질을 대사하는 해독효소로 알려져 있으나 지각류에서는 그 기능에 대해서는 잘 알려져 있지 않다. 본 연구에서는 기수산 물벼룩 Diaphanosoma celebensis에서 clan 2, 3, 4에 각각 속하는 CYP 유전자 9종(clan 2: CYP370A4, CYP370C5; clan 3: CYP350A1, CYP350C5, CYP361A1; clan 4: CYP4AN-like, CYP4AP2, CYP4AP3, CYP4C33-like1)의 서열에 대해 진화적으로 보존된 서열의 유사도를 분석하고 계통분석을 실시하였다. 또한 3종류의 서로 다른 크기의 polystyrene beads (0.05-, 0.5-, 6-㎛ PS beads; 0.1, 1, and 10 mg/L)에 48시간 노출된 기수산 물벼룩에서 이들 9종의 CYP 유전자의 발현을 real time reverse transcription polymerase chain reaction (RT-PCR)로 분석하였다. 결과적으로 기수산 물벼룩 CYP 유전자는 모두 진화적으로 보존된 motif를 가지고 있으며 계통분석 결과 각각 clan 2, 3, 4에 속하는 것으로 확인되었다. 이는 기능적으로 보존되어 있음을 의미한다. CYP 유전자 중 clan 2에 속하는 CYP370C5와 clan 3에 속하는 CYP360A1, 그리고 clan 4에서는 CYP4C122 유전자의 발현이 0.05-㎛ PS beads에 노출되었을 때 유의하게 증가하는 양상을 보였으며, 이는 이들 유전자가 PS 대사에 관여한다는 것을 의미한다. 본 연구는 미세플라스틱이 해양 무척추 동물에 미치는 생물 영향을 분자적 수준에서 이해하는데 도움이 될 것이다.

• 한국환경성돌연변이발암원학회지
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• 제24권4호
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• pp.155-162
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• 2004

In mammalian, cytochrome P4501A1 (CYP1A1) is very important for metabolism of xenobiotics such as PAHs(Polycyclic aromatic hydrocarbon) and heterocyclic amine, and it is induced by environmental contaminants such as PAHs, TCDD(2,3,7,8-tetrchlorodibenzo-p-dioxin) and 3-MC (3-methylcholanthrene). In fish, like mammalian, when it is exposed to environmental contaminants, they cause specific and sensitive induction of CYP1A. Therefore, induction of CYP1A in fish and mammalian is widely used as a biomarker for exposure of environmental contaminants. In this study, to compare the function of Cyp1a1 in fish with it in mammalian, we have used rainbow trout(Oncorhynchys mykiss) hepatoma cells (RTH-149) and mouse hepatocyte (Hepa-I). in order to examine induction of Cyp1a1 by TCDD, we have used the bioassay system. We examined effects of TCDD on the Cyp1a1-luciferase reporter gene activity, 7-ethoxyresorufin O-deethylase(EROD) activity and Cypa mRNA level.

• 한국환경성돌연변이발암원학회지
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• 제24권3호
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• pp.143-150
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• 2004

In mammalian, cytochrome P4501A1 (CYP1A1) is very important for metabolism of xenobiotics such as PAHs(Polycyclic aromatic hydrocarbon) and heterocyclic amine, and it is induced by environmental contaminants such as PAHs, TCDD(2,3,7,8-tetrchlorodibenzo-p-dioxin) and 3-MC (3-methylcholanthrene). In fish, like mammalian, when it is exposed to environmental contaminants, they cause specific and sensitive induction of CYP1A. Therefore, induction of CYP1A in fish and mammalian is widely used as a biomarker for exposure of environmental contaminants. In this study, to compare the function of Cyp1a1 in fish with it in mammalian, we have used rainbow trout(Oncorhynchys mykiss) hepatoma cells (RTH-149) and mouse hepatocyte (Hepa-I). in order to examine induction of Cyp1a1 by TCDD, we have used the bioassay system. We examined effects of TCDD on the Cyp1a1-luciferase reporter gene activity, 7-ethoxyresorufin O-deethylase(EROD) activity and Cypa mRNA level.

• Environmental Analysis Health and Toxicology
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• 제20권3호
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• pp.209-213
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• 2005

Due to steady increase of childhood asthma, exposure to air toxics including PAHs have been thought as an etiology for the asthma. PAHs -involvement in airway inflammation, such as IgE production, is the potential mechanism of the PAHs-induced asthma. Cytochrome P450s (CYPs), particularly CYP1A1 is known enzyme to metabolite PAHs and to be induced by PAHs. The CYP1A1 expression has been emphasized as an biomarker for PAHs - exposure. The present study was performed to clarify the etiology of childhood asthma with PAHs-exposure using mRNA expression of CYP1A1 . The study Objects were Korean children who were asthma patients (cases) or other hospital controls (N=20; age,3 $\~$ 16; boys,56$\%$). As result, we detected expression of the CYP1A1 in all peripheral blood specimens which were collected from the subjects. Moreover, we found approx. 300 fold-higher expression of the CYP1A1 in the cases than that in the controls (p(<)0.01). When we considered age which was related to Asthma, the above significant trend was somewhat diluted, however, the relation between asthma and the Cypih i expression waL stronger than that between asthma and age (chi square,7.99 vs. 3.34). Therefore, our study supports that PAHs induce or worse childhood asthma and suggests application of expression of the CYP1A1 as an initiation or progress biomarker for PAHs - induced childhood asthma.

• 한국어병학회지
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• 제33권2호
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• pp.153-161
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• 2020

Cytochrome P450(CYP) gene is involved in the biotransformation of drugs and environmental pollutants. In this study, we analyzed the nucleotide sequence of the Anguilla japonica CYP1(AjCYP1) family gene and examined the relative expression of AjCYP1A, AjCYP1B and AjCYP1C1 in response to the exposure to environmental pollutants. After exposure to B[a]P 20mg/kg bw, the expression of AjCYP1 family gene increased over time. Among four tissues examined (liver, spleen, gill and kidney), AjCYP1 family gene was expressed significantly in the kidney. Compared with the control group, AjCYP1A was expressed about 5-fold at 48 hr, AjCYP1B about 6-fold at 24 hr, and AjCYP1C1 about 4-fold at 24 hr. However, after exposure to B[a]P 200mg/kg bw, AjCYP1A did not change in all tissues. On the other hand, AjCYP1B was expressed at about 4-fold at 24 hr in the spleen and 4-fold at 48 hr in the gill. Finally AjCYP1C1 was expressed 3.7-fold and 4.3-fold in the spleen and kidneys at 48 hr, respectively. Taken together, our results suggest that the expression of AjCYP1 gene in eel tissues might be used as a useful tool to assess the exposure to environmental pollutants in aquaculture system.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.415-421
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• 2004

Cytochrome P450 3A4 (CYP3A4) is the most abundant CYPs in human liver, comprising approximately $30\%$ of the total liver CYPs contents and is involved in the metabolism of more than $60\%$ of currently used therapeutic drugs. However, the molecular mechanisms underly-ing regulation of CYP3A4 gene expression have not been understood. Thus, this study has been carried out to gain the insight of the molecular mechanism of CYP3A4 gene expression, investigating if the histone deacetylation is involved in the regulation of CYP3A4 gene expression by proximal promoter. Also SXR was investigated to see if they were involved in the regulation of CYP3A4 proximal promoter activity. Hepa-1 cells were transfected with a plasmid containing ${\~}1kb$ of the human CYP3A4 proximal promoter region (863 to +64 bp) cloned in front of a reporter gene, luciferase, in the presence or absence of SXR. Transfected cells were treated with CYP3A4 inducers such as rifampicin, PCN and RU 486, in order to examine the regulation of CYP3A4 gene expression in the presence or absence of trichostatin A (TSA). In Hepa-1 cells, CYP3A4 inducers increased modestly the luciferase activity when TSA was co-treated, but this increment was not enhanced by SXR cotransfection. Taken together, these results indicated that the inhibition of histone deacetylation was required to SXR-mediated increase in CYP3A4 proximal promoter region when rifampicin, or PCN was treated. Further a trans-activation by SXR may demand other species-specific transcription factors.

• Animal Bioscience
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• 제34권2호
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• pp.312-319
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• 2021

Objective: Stress-induced cytotoxicity caused by xenobiotics and endogenous metabolites induces the production of reactive oxygen species and often results in damage to cellular components such as DNA, proteins, and lipids. The cytochrome P450 (CYP) family of enzymes are most abundant in hepatocytes, where they play key roles in regulating cellular stress responses. We aimed to determine the effects of the antioxidant compound, methylsulfonylmethane (MSM), on oxidative stress response, and study the cytochrome P450 family 3 subfamily A (CYP3A) gene expression in fetal horse hepatocytes. Methods: The expression of hepatocyte markers and CYP3A family genes (CYP3A89, CYP3A93, CYP3A94, CYP3A95, CYP3A96, and CYP3A97) were assessed in different organ tissues of the horse and fetal horse liver-derived cells (FHLCs) using quantitative reverse transcription polymerase chain reaction. To elucidate the antioxidant effects of MSM on FHLCs, cell viability, levels of oxidative markers, and gene expression of CYP3A were investigated in H2O2-induced oxidative stress in the presence and absence of MSM. Results: FHLCs exhibited features of liver cells and simultaneously maintained the typical genetic characteristics of normal liver tissue; however, the expression profiles of some liver markers and CYP3A genes, except that of CYP3A93, were different. The expression of CYP3A93 specifically increased after the addition of H2O2 to the culture medium. MSM treatment reduced oxidative stress as well as the expression of CYP3A93 and heme oxygenase 1, an oxidative marker in FHLCs. Conclusion: MSM could reduce oxidative stress and hepatotoxicity in FHLCs by altering CYP3A93 expression and related signaling pathways.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2647-2653
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• 2012

Involvement of cytochrome P450 genes (CYPs) in breast cancer (BCa) may differ between populations, with expression patterns affected by tumorigenesis. This may have an important role in the metabolism of anticancer drugs and in the progression of cancer. The aim of this study was to determine the mRNA expression patterns of four cytochrome P450 genes (CYP2W1, 3A5, 4F11 and 8A1) in Mexican women with breast cancer. Real-time PCR analyses were conducted on 32 sets of human breast tumors and adjacent non-tumor tissues, as well as 20 normal breast tissues. Expression levels were tested for association with clinical and pathological data of patients. We found higher gene expression of CYP2W1, CYP3A5, CYP4F11 in BCa than in adjacent tissues and only low in normal mammary glands in our Mexican population while CYP8A1 was only expressed in BCa and adjacent tissues. We found that Ki67 protein expression was associated with clinicopathological features as well as with CYP2W1, CYP4F11 and CYP8A1 but not with CYP3A5. The results indicated that breast cancer tissues may be better able to metabolize carcinogens and other xenobiotics to active species than normal or adjacent non-tumor tissues.

• Toxicological Research
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• 제32권3호
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• pp.207-213
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• 2016

Although propolis is one of the most popular functional foods for human health, there have been no comprehensive studies of herb-drug interactions through cytochrome P450 (CYP) inhibition. The purpose of this study was to determine the inhibitory effects of propolis on the activities of CYP1A2, 2A6, 2B6, 2C9, 2C19, 2D6, 2E1 and 3A4 using pooled human liver microsomes (HLMs). Propolis inhibited CYP1A2, CYP2E1 and CYP2C19 with an $IC_{50}$ value of 6.9, 16.8, and $43.1{\mu}g/mL$, respectively, whereas CYP2A6, 2B6, 2C9, 2D6, and 3A4 were unaffected. Based on half-maximal inhibitory concentration shifts between microsomes incubated with and without nicotinamide adenine dinucleotide phosphate, propolis-induced CYP1A2, CYP2C19, and CYP2E1 inhibition was metabolism-independent. To evaluate the interaction potential between propolis and therapeutic drugs, the effects of propolis on metabolism of duloxetine, a serotonin-norepinephrine reuptake inhibitor, were determined in HLMs. CYP1A2 and CYP2D6 are involved in hydroxylation of duloxetine to 4-hydroxy duloxetine, the major metabolite, which was decreased following propolis addition in HLMs. These results raise the possibility of interactions between propolis and therapeutic drugs metabolized by CYP1A2.