• Korean Journal of Environmental Biology
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• v.29 no.1
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• pp.74-80
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• 2011

In this study we present a mammalian cell culture model that allows to study the effect of endocrine disruptors (EDCs) on aromatase activity of aquatic amphibian, Bombina orientalis. Bombina orientalis aromatase gene was subcloned into a mammalian expression vector and subsequently transfected to mammalian cells. Although the protein expression level of Bombina orientalis aromatase was low, it had a significant aromatase activity. When EDCs were added to aromatase transfected cells, aromatase activity was significantly decreased. We report here that this system may be used to monitor the effect of EDCs on aromatase activity of aquatic organisms.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.136-148
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• 2002

본 연구는 osteoblastic cells에서 estogen 의 생합성을 유도하는 aromatase의 activity에 대한 봉독(蜂毒)작용을 측정하여, 봉독치료시 Arthritis의 진행 억제 및 estogen의 의한 bone formation의 효과여부를 검증하기 위해 실행하였다. 사용된 세포주로는 Osteoblastic phenotype으로 분화가 유도되는 Human leukaemic cell line FLG 29.1 및 the primary first-passage osteoblastic cells (hOB cells)이며, 이들을 각각 배양하고 각각의 RNA를 isolation한 뒤 PCR 증폭을 하였다. Aromatase에 대한 활성인자인 TPA와 TGF-${\beta}1$ 및 봉독을 이용하여 aromatase의 expression 및 activity에 대해 미치는 영향을 측정한 바, aromatase expression은 FLG 29.1 cell와 hoB cells에서, 50nM TPA 24시간 처리, 봉독 2 ~ 4시간 처리와 TGF-${\beta}1$ 3시간 처리로 유도한 결과 TPA와 TGF-${\beta}1$의 경우는 서로 유사하였고, 봉독에서 상대적으로 높게 나타났다. Aromatase activity는 FLG 29.1 cell, hoB cells에서 24시간 incubation한 결과, 모든 실험에서 일정하게 선상증가를 보였다. $5{\mu}{\ell}/m{\ell}$ BV에서 TPA와 TGF-${\beta}1$보다 뚜렷하게 증가하였으며, 0.5mM Bt2-cAMP, 50nM dexametasone처리에서는 유의성이 없었다. Estrogen 생합성을 촉매하는 aromatase activity BV가 처리에서 현저하게 증가하였기에, Rheumatis arthritis의 bone destruction에 대해 BV가 효과적인 역할을 할 것으로 보여진다.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.95-100
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• 2003

Dichlorodiphenyltrichloroethane (DDT), is a widespread environmental pollutant. In this study, we investigated the effect of DDT on testosterone production through aromatase and investigated its molecular mechanism in testicular leydig cell, R2C. We investigated that the effects of DDT on testosterone production and its effects on aromatase activity in R2C cell by radio immunoassay (RIA). As the results, the potent leyding cell activator LH increased testosterone production compared to the control. DDT exposure significantly decreased testosterone production in R2C cell and DDT alone affected T reduction in a dose-dependent manner in R2C cell slightly. In addition, DDT was found to increase aromatase activity in R2C cell in a dose dependent manner. In order to assess whether the suppressive effects of DDT on LH-inducible testosterone production might be influenced by the ER, ICI 182.780, a pure antiestrogen, was used, and it was found that these inhibitory effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the suppressive effects of DDT. Furthermore, the inducible effects of DDT on aromatase might be influenced by the ER, ICI 182.780 was used, and it was found that these enhancing effects of DDT were antagonized by ICI 182.780, implying that the ER mediates the inducible effects of DDT. Our results indicated that DDT inhibition of LH-inducible testosterone production in R2C is mediated through aromatase. However, the precise mechanisms by which DDT enhance in leyding cell remains unknown. The current study suggests the possibility that DDT might act as a modulator aromatase gene transcription.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.315-324
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• 2004

Cytochrome P450 aromatase is the enzyme responsible for biosynthesis of female sex hormone(estrogen) and 19-nortestosterone(nandrolone), a unique steroid hormone endogenously synthesized in the pig. By use of RT-PCR coupled with DHPLC technique (WAVE analysis), expression pattern of isoforms of porcine cytochrome P450 aromatase gene was investigated. Relatively higher expression of aromatase mRNA was observed in testis than in ovary and this result accounted for the previous findings of higher blood estrogen level in male compared with female in this species. The result from the DHPLC demonstrated that PCR amplified DNA fragments of ovary and testis tissues. using unique PCR primers for all three types of aromatase genes, were different from those of type II and ill genes. Further nucleotide sequence analyses of the plasmid clones containing the PCR products revealed that nucleotide sequences of all clones were identical to type I aromatase gene(ovary type). Thus, the result from the present study indicates that the ovary and testis express the same type of aromatase gene. Therefore, the efficacy of DHPLC techniques used for this study helped us to analyze tissue-specific expression of isoform of genes containing the nucleotide sequences with high homology.

• Korean Journal of Pharmacognosy
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• v.35 no.2 s.137
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• pp.147-151
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• 2004

Water extracts from Thesium chinense Tunczaninov (TCTW) and Prunella vulgaris L. (PVW) were tested for aromatase and cyclooxygenase activities. TCTW and PVW were capable of suppressing aromatase in a human placenta microsomal assay. PVW was shown to be more effective than TCTW in the suppression of aromatase activity. TCTW significantly inhibited cyclooxygenase-2 (COX-2) activity at the concentration of 0.25 (p<0.05), 0.5 (p<0.01) and 2.5 mg/ml (p<0.005). PVW also inhibited COX-2 activity in a dose-dependent manner in a concentration range of $0.05{\sim}2.5\;mg/ml$. The expression of COX-2 was inhibitied by TCTW and PVW in western blot analysis. These results suggest that TCTW and PVW may have breast cancer chemopreventive potentials by inhibiting aromatase and cyclooxygenase activities.

• Development and Reproduction
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• v.10 no.3
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• pp.197-202
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• 2006

Sex steroids are generally considered as natural sex inducers in fish, and aromatase (cytochrome P450 aromatase) that catalyzes androgens into estrogens in the steroidogenic pathway is also known to be involved in sex differentiation. The timing of aromatase action is, thus, of central importance in the study of fish sex differentiation. We treated sexually undifferentiated tilapia (Oreochromis niloticus) larvae with $Fadrozole^{TM}$, a non-steroidal aromatase inhibitor (AI), by immersing the fish in a solution containing AI during the sex differentiation period to narrow down the critical period of aromatase action. Fish were treated once at 11 or 13 days post fertilization (dpf), or twice at 11 and 13 dpf. The concentrations of AI at each time of the treatment were 0 mg/L (control), 50 mg/L or 100 mg/L. Survival rate was not statistically associated with AI immersion treatment (p>0.25). However, sex ratio was significantly altered by the treatment, with higher concentration and double immersion being more effective in masculinizing genetic females (p<0.05). These results suggest that aromatase action for sex differentiation in this fish species would begin at least from 11 dpf which is much earlier than previously expected, and that only 3 hours of brief immersion in AI solution is powerful enough to alter genetically programed sex.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8975-8979
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• 2014

Objective: To explore the possible significance of aromatase P450 in endometrial hyperplasia with a background of polycystic ovary syndrome (PCOS). Methods: Immunohistochemistry was used to determine the expression of aromatase P450 in endometrium of PCOS patients. Semiquantitative analysis of aromatase P450 expression of mRNA and protein level wasalso carried out by real-time quantitative RT-PCR method. After endometrial cells were stimulated by testosterone and letrozole in vitro, the estradiol ($E_2$) level was determined, and the expression of cell aromatase P450 mRNA was assessed. Results: The aromatase P450 mRNA level was increased in endometria of PCOS patients. When endometrial cells were cultured with $10^{-6}M$ testosterone, the $E_2$ level in the culture medium increased. An inhibitory effect on $E_2$ generation and expression of aromatase P450 mRNA was observed when the endometrial cells were treated with $10^{-5}M$ letrozole. Conclusions: There is an increased expression of aromatase P450 in PCOS patient endometrium. Androgen stimulation could enhance the synthesis of aromatase P450 mRNA and the production of $E_2$ in endometrial cells in vitro while letrozole could do the reverse.

• Development and Reproduction
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• v.11 no.3
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• pp.195-203
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• 2007

Sex determination and sex differentiation are influenced by genotype in many gonochoristic fish. Cytochrome P450 aromatase (CYP19) is the terminal enzyme in steridogenic pathway that converts androgens into estrogens. In this study, partial fragments of aromatase genes (ovarian aromatase, P450aromA and brain aromatase, P450aromB) were cloned and sequenced in Korean rockfish (Sebastes schlegeli), and gene specific primers were designed based on their sequences. Using these primers, aromatase gene expression during sex differentiation was investigated by RT-PCR. Expression of these aromatase genes were detected both in the head and body parts at 35 dab (days after birth). The number of fish that expressed the aromatase genes decreased at 52 dab, implying down-regulation of these genes. However, these genes were expressed at 59 dab in almost all fish studied here. The expression patterns of both genes are similar throughout the investigated period except for 45 dab where the expression of P450aromB was detected in more fish than that of P450aromA both in the head and body parts. Timing of sex differentiation in this species has been shown to be at around $50{\sim}65$ dab by histological analysis. However, the results from this study suggest that sex differentiation of rockfish may take place $1{\sim}2$ weeks earlier than the period proposed previously. The results also suggest that the mechanism of sex differentiation in viviparous fish may be similar to that in oviparous fish in terms of the importance of aromatase action during the critical period.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.3-5
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• 2003

여성호르몬으로 잘 알려진 estrogen은 난소의 granulosa 세포와 정소의 Sertoli 세포에서 주로 생성되는 것으로 알려져 있으며 최근엔 사람의 지방, 근육, 뇌, 뼈세포 등에서의 합성 가능성과 각 조직에서 생성되는 estrogen 의 생리학적인 기능에 관해 많은 관심이 모여져 왔다. 다른 steroid처럼 지방친화적인 (lipophilic) estrogen은 세포막과 핵막을 쉽게 통과하여 목표세포 (target cell)의 핵에 존재하는 estrogen receptor (ER)에 결합하여 특정 유전자를 발현에 관여하는 것으로 알려져 있다. Cytochrome P450 Aromatase (간략히, aromatase)는 steroid hormone을 합성하는 마지막 단계에서 androgens을 estrogens으로 전환시키는데 관여하는 효소이다. Aromatase의 substrate (기질)로 사용되는 androgen에는 androstenedione과 testosterone 등이 있으며, 최종 산물로써 estrone(E1)이나 17$\beta$-estradiol(E2) 등의 estrogen이 생성된다. Aromatase는 steroidogenic tissues의 세포내 골지체에 존재하는 것으로 알려져 있으며, NADPH-cytochrome P450 reductase와 함께 복합체로써 존재한다. NADPH-cytochrome P450 reductase는 다른 steroid hormone에 관여하는 효소들과도 복합체를 형성하여 다른 steroid hormone을 합성할 수 있으므로, 어떤 조직에서 여성호르몬이 만들어질 수 있느냐 하는 것은 그 조직에서 aromatase 단백질이 만들어지느냐에 따라서 결정된다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1999.04a
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• pp.5-8
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• 1999

여성의 breast cancer의 1/3 의 경우가 hormone-dependent에 의한 것이다. 따라서 그 치료의 접근 방법으로써 estrogen receptor에 작용하거나, receptor-mediated gene trenscription을 저해하는 antiestrogen을 사용하는 것이 있다. Estrogen은 microsomal cytochrome P-450 enzyme complex system에 의해 androgen으로부터 생합성되는 hormone이며, estrogen product는 steroid product의 biosynthetic sequence의 마지막 단계에서 생산되고, aromatase는 이에 관여하는 enzyme으로써, aromatase를 선택적으로 저해하는 경우에 다른 steroid의 생산에 영향을 미치지 않고 estrogen 생산을 감소 시킬 수 있다. 이러한 관점에서, aromatase를 선택적으로 저해하는 것은 hormone-dependent breast cancer를 완화시킬 수 있는 가능성을 가진 cancer chernopreventive agents의 새로운 방법이라 할 수 있다.