• Title/Summary/Keyword: cyp3a4 inhibitors

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Cloning of Elicitor-Inducible 5-epi-Aristolochene Hydroxylase in Tobacco Cell Suspension Culture (담배 현탁배양 세포의 Elicitor 유도성 5-epi-Aristolochene Hydroxylase 유전자의 클로닝)

  • Soon Tae Kwon;In-Jung Lee;Joseph Chappell
    • Journal of Life Science
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    • v.8 no.5
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    • pp.604-613
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    • 1998
  • The last enzyme of the sesquiterpen phytoalexin capsidiol synthesis in tobacco cell, 5-epi-aristolochene hydro-xylase which convert 5-epi-aristolochene (EAS) to capsidiol, was cloned by a reverse transcription polymerase chain reaction strategy and cDNA library screening. Cloned CYP-B3 contained high probability amino acid matches to known plant cytochrome P450 sequences and open reading frame with the conserved FxxGxRxCxG heme-binding region. Transcripts of CYP-B3 were not detected in control cells, but induced in elicitor-treated cells. Furthermore, CYP-B3 transcripts were induced by fungal extracts and cellulase but not by other stimuli(chilling, heat shock and 2,4-D). Induction of CYP-B3 transcripts by elicitor treatment was not affected by ancymidol and ketoconazole treat-ments suggesting that an inhibition of hydroxylase activity by Cyt P450 inhibitors resulting from post translational processing event.

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The effects of the standardized extracts of Ginkgo biloba on steroidogenesis pathways and aromatase activity in H295R human adrenocortical carcinoma cells

  • Kim, Mijie;Park, Yong Joo;Ahn, Huiyeon;Moon, Byeonghak;Chung, Kyu Hyuck;Oh, Seung Min
    • Environmental Analysis Health and Toxicology
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    • v.31
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    • pp.10.1-10.8
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    • 2016
  • Objectives Aromatase inhibitors that block estrogen synthesis are a proven first-line hormonal therapy for postmenopausal breast cancer. Although it is known that standardized extract of Ginkgo biloba (EGb761) induces anti-carcinogenic effects like the aromatase inhibitors, the effects of EGb761 on steroidogenesis have not been studied yet. Therefore, the effects of EGb761 on steroidogenesis and aromatase activity was studied using a H295R cell model, which was a good in vitro model to predict effects on human adrenal steroidogenesis. Methods Cortisol, aldosterone, testosterone, and $17{\beta}$-estradiol were evaluated in the H295R cells by competitive enzyme-linked immunospecific assay after exposure to EGb761. Real-time polymerase chain reaction were performed to evaluate effects on critical genes in steroid hormone production, specifically cytochrome P450 (CYP11/ 17/19/21) and the hydroxysteroid dehydrogenases ($3{\beta}$-HSD2 and $17{\beta}$-HSD1/4). Finally, aromatase activities were measured with a tritiated water-release assay and by western blotting analysis. Results H295R cells exposed to EGb761 (10 and $100{\mu}g/mL$) showed a significant decrease in $17{\beta}$-estradiol and testosterone, but no change in aldosterone or cortisol. Genes (CYP19 and $17{\beta}$-HSD1) related to the estrogen steroidogenesis were significantly decreased by EGb761. EGb761 treatment of H295R cells resulted in a significant decrease of aromatase activity as measured by the direct and indirect assays. The coding sequence/Exon PII of CYP19 gene transcript and protein level of CYP19 were significantly decreased by EGb761. Conclusions These results suggest that EGb761 could regulate steroidogenesis-related genes such as CYP19 and $17{\beta}$-HSD1, and lead to a decrease in $17{\beta}$-estradiol and testosterone. The present study provides good information on potential therapeutic effects of EGb761 on estrogen dependent breast cancer.

Clinical Study for Efficacy and Safety of Rabeprazole Sodium(Pariet) in the Treatment of Laryngopharyngeal Reflex(LPR) Disease (인후두위산역류증(Laryngopharyngeal Reflux: LPR)의 치료에 대한 RabeprazoleSodium(Parietd)의 임상효과와 안전성 검토)

  • Jung, K.W.;Jun, B.S.;Ko, S.H.;Kwon, K.H.;Kwon, S.Y.;Kwon, J.K.;Kim,, D.Y.;Kim,, S.C.;Kim,, S.W.;Kim,, Y.M.;Kim,, Y.H.;Kim,, Y.H.;Kim,, J.M.
    • Korean Journal of Bronchoesophagology
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    • v.10 no.2
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    • pp.35-42
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    • 2004
  • Background and objective : Rabeprazole is a new generation proton pump inhibitor, which has a rapid onset after first dose, predictable efficacy in all patients regardless of CYP2C19 genotype status, and less nocturnal acid breakthrough. The aim of the study is to investigate clinical efficacy and safety of rabeprazole sodium (Pariet 10mg qd)when administered once daily to patients with laryngopharyngeal reflux(LPR) disease. Methods : Among the patients who had visited the Department of Otolaryngology, those with LPR symptoms, had undergone laryngoscopy. Symptoms and endoscopic laryngeal sings were recorded initially, at 1 month, 2 months, 3 months, and more than 3 months, All patients were evaluated for clinical efficacy on the basis of symptom scores, reflux finding score(RFS), and side effects. Results : In general, most symptom scores and RFS improved over the time. Efficacy of the Pariet on LPR-related symptoms were $63.2\%,\;77.5\%,\;78.7\%,\;and\;90.9\%$ before 4 weeks, 4 to 8 weeks, 8 to 12 weeks, and after 12 weeks respectively. Efficacy on the RFS were $61.8\%,\;78.4\%,\;82.9\%,\;and\;85.5\%$ before 4 weeks, 4 to 8 weeks, 8 to 12 weeks, and after 12 weeks respectively. Pariet was well tolerated and was associated with few drug-related side effects. Conclusion Because of its efficacy and safety, Pariet may prove to be an alternative to currently available proton pump inhibitors.

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