• Mass Spectrometry Letters
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• 제13권4호
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• pp.152-157
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• 2022

Schisandra chinensis and its fruits have been used as a traditional herbal medicine to treat liver dysfunction, fatigue, and chronic coughs. Several in vitro and in vivo studies suggested that dibenzocyclooctadiene lignans present in Schisandra fruits strongly inhibit CYP3A4 activity. However, reports on the inhibitory potential of dietary Schisandra supplements against CYP3A activity are limited despite their increasing consumption as dietary supplements. In this study, we evaluated the CYP3A-inhibitory potential of four dietary Schisandra supplements in human liver microsomes. At a concentration of 0.05 mg/mL, Schisandra supplements from Nature's Way, Swanson, Planetary Herbals, and Only Natural inhibited CYP3A activity by 93.9, 70.8, 33.6, and 24.8%, respectively. Nature's Way, which exhibited the strongest inhibition against CYP3A, had the highest contents of gomisin B and gomisin C, which potently inhibit CYP3A activity. The in vivo pharmacokinetics of this product should be examined to determine whether the clinical relevance of inhibiting CYP3A activity by dietary Schisandra supplementation.

• 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.

• Mass Spectrometry Letters
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• 제9권1호
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• pp.24-29
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• 2018

DC23, a triazolothione resorcinol analogue, is known to inhibit heat shock protein 90 and pyruvate dehydrogenase kinase which are up-regulated in cancer and diabetes, respectively. This study was performed to elucidate the metabolism of DC23 in human liver microsomes (HLMs). HLMs incubated with DC23 in the presence of uridine 5'-diphosphoglucuronic acid (UDPGA) and/or ${\beta}$-nicotinamide adenine dinucleotide phosphate (NADPH) resulted in the formation of four metabolites, M1-M4. M1 was identified as DC23-N-Oxide, on the basis of LC-MS/MS analysis. DC23 was further metabolized to its glucuronide conjugates (M2, M3, and M4). In vitro metabolic stability studies conducted with DC23 in HLMs revealed significant glucuronide conjugation with a $t_{1/2}$ value of 1.3 min. The inhibitory potency of DC23 on five human cytochrome P450s was also investigated in HLMs. In these experiments, DC23 inhibited CYP2C9-mediated tolbutamide hydroxylase activity with an $IC_{50}$ value of $8.7{\mu}M$, which could have implications for drug interactions.

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.271.1-271.1
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• 2000

• 대한한의학회지
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• 제24권2호
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• pp.40-46
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• 2003

Objectives : Achyranthes bidentata radix (Usul) has been used as anti-arthritic, antiallergic, antidiuretic, and so on. Recently extracts of Achyranthes bidentata radix have shown anti-inflammatory and cancer preventive effects in vitro and in vivo. Methods : We therefore evaluated the inhibitory potential of ethanol extracts of Achyranthes bidentata radix on cytochrome P450 (CYP) isoforms-catalyzed reactions, which relate to causes of cancer and inflammation, including CYP1A2, CYP2C9, CYP2C19, CYP2E1, CYP2D6, CYP2C8, and CYP3A4, using human liver microsomal preparations. Results : The extracts showed weak or negligible inhibitory effects on CYP2C9-catalyzed (S)-warfarin 7-hydroxylation, CYP2C19-catalyzed S-mephenytoin 4-hydroxylation, and CYP2D6-catalyzed dextromethorphan O-demethylation with each IC50 over 1750 g/ml, respectively. However, it showed relatively significant inhibitory effect on CYP1A2-catalyzed phenacetin O-deethylation and CYP2E1-catalyzed chlorzoxazone 6-hydroxylation with IC50s of 970.5 g/ml and 821.4 g/ml, respectively. Conclusions : These results suggest that extracts of Achyranthes bidentata radix have inhibitory effects on CYP-catalyzed reactions, especiallyCYP1A2 and CYP2E1, in human liver microsomes. These effects appear to relate to anti-inflammatory and cancer prevention following decrease of reactive oxygen species formed by CYP, especially CYP1A2 and CYP2E1, by Achyranthes bidentata radix. However, further evaluation is necessary to demonstrate and to confirm its effects in human.

• Mass Spectrometry Letters
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• 제7권4호
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• pp.106-110
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• 2016

Ginseng, a traditional herbal drug, has been used in Eastern Asia for more than 2000 years. Various ginsenosides, which are the major bioactive components of ginseng products, have been shown to exert numerous beneficial effects on the human body when co-administered with drugs. However, this may give rise to ginsenoside-drug interactions, which is an important research consideration. In this study, acassette assay was performed the inhibitory effects of 12 ginsenosides on seven cytochrome P450 (CYP) isoforms in human liver microsomes (HLMs) using LC-MS/MS to predict the herb-drug interaction. After incubation of the 12 ginsenosides with seven cocktail CYP probes, the generated specific metabolites were quantified by LC-MS/MS to determine their activities. Ginsenoside Rb1 and F2 showed strong selective inhibitory effect on CYP2C9-catalyzed diclofenac 4'-hydroxylation and CYP2B6-catalyzed bupropion hydroxylation, respectively. Ginsenosides Rd showed weak inhibitory effect on the activities of CYP2B6, 2C9, 2C19, 2D6, 3A4, and compound K, while ginsenoside Rg3 showed weak inhibitory effects on CYP2B6. Other ginsenosides, Rc, Rf, Rg1, Rh1, Rf, and Re did not show significant inhibitory effects on the activities of the seven CYPs in HLM. Owing to the poor absorption of ginsenosides after oral administration in vivo, ginsenosides may not have significant side effects caused by interaction with other drugs.

• Toxicological Research
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• 제11권1호
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• pp.23-29
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• 1995

Microsomes from human liver sample HL 110 oxidized aflatoxin $B_1$ $(AFB_1)$ to $AFB_1$ exo-8, 9-epoxide which was detected as a glutathione (GSH) conjugate with excess GSH S-transferase and to aflatoxin $Q_1$ ($AFB_1$; 3$\alpha$-hydroxyafiatoxin $B_1$), and testosterone to 6$\beta$-hydroxytestosterone. Anti-P450 3A4 nearly completely inhibited all of the reactions. Some fiavonoids inhibited all of the reactions. While other fiayonolds stimulated 8, 9-epoxidation and inhibited 3$\alpha$-hydroxylation. Gestodene inhibited all of the reactions when gestodene was metabolized by human liver microsomal P450 3A4 prior to adding substrate. But, ges-todene was added in the enzyme mixtures in the presence of $AFB_1$, it could not inhibit 8, 9-epoxidation of $AFB_1$. Nifedipine and troleandomycin inhibited both of the reactions of $AFB_1$ but only 3$\alpha$-hydroxylation was inhibited by the oxidation product of nifedipine. Although, troleandomycin was known as a mechanism-based inhibitor, the chemical did not show any detectable inhibitory effect on 6$\beta$-hydroxylation of testosterone. The results suggest that there are several different substrate-binding sites on P450 3A4.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of the Pharmaceutical Society of Korea
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• pp.239-239
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• 2001

• Mass Spectrometry Letters
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• 제7권3호
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• pp.69-73
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• 2016

High-resolution quadrupole-Orbitrap mass spectrometry (HRMS), with high-resolution (> 10,000 at full-width at half-maximum) and accurate mass (< 5 ppm deviation) capabilities, plays an important role in the structural elucidation of drug metabolites in the pharmaceutical industry. ML106, a derivative of imidazobenzimidazole, decreased melanin content and tyrosinase activity in a dose-dependent manner. Here, we investigated the phase 1 metabolic pathway of ML106 using HRMS in human liver microsomes (HLMs) and recombinant cDNA-expressed cytochrome P450 (CYP). After the incubation of ML106 with pooled HLMs and recombinant cDNA-expressed CYP in the presence of NADPH, five phase 1 metabolites, including three mono-hydroxylated metabolites (M1-3) and two di-hydroxylated metabolites (M4 and M5), were investigated. The metabolite structures were postulated by the elucidation of protonated mass spectra using HRMS. The CYP isoforms related to the hydroxylation of ML106 were studied after incubation with recombinant cDNA-expressed CYP. Here, we identified the phase 1 metabolic pathway of ML106 induced by CYP in HLMs.

• Environmental Analysis Health and Toxicology
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• 제16권2호
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• pp.97-102
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• 2001

FMOs (Flavin-containing monooxygenases, EC1.14.13.8)는 다양한 종류의 식품, 약물이나 기타 외래 유래물질 (xenobiotics)를 산화시키는 NADPH와 $O_2$ 의존성 약물대사효소이다. 현재까지 5종의 subfamily가 존재하는 것으로 보고되어 있으며 그 중 잘 알려진 FMO3는 대표적 인 subfamily로서 주로 간에 존재한다 사람FMO에 관한 연구는 최근 들어 활성화되기 시작했으며 질소, 황이나 인 등을 포함하는 친핵성 (nucleophilic) 화합물이 대표적인 기질로 보고되어 있다. 본 연구에서는 thiocarbamide를 포함하고 있는 화합물에 대한 사람의 FMO3의 기질 특이성을 알아보고자 하였다. 사람 FMO3를 baculovirus system을 이용하여 대량으로 발현시킨 후 그 microsomal FMO3를 분리하여 thiocholine assay를 시행하였다. 그 결과 methimazole, thiourea, and phenylthiourea는 낮은 $K_{m}$ (4-10$\mu$M)간을 갖는 반면, 이보다 기질의 크기가 큰 1 ,3-diphenylthiourea, 1, 3-bis (3, 4-dichlorophenyl)-2-thiourea, 1, 1-dibenzyl-3-phenol-2-thiourea에서는 효소활성이 나타나지 않았다. 이는 사람 fM01과 비교하여 볼 때 큰 차이는 없었으며, 다른 pig, guinea pig, rat, rabbit에서 보다 받아들일 수 있는 기질의 크기가 더 제한적임을 알 수 있었다.