• BMB Reports
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• 제32권3호
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• pp.226-231
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• 1999

In vitro effects of acetone on cytochrome P450 (P450)-dependent benzo(a)pyrene (B(a)P) hydroxylation supported by cumene hydroperoxide (CuOOH) or NADPH/$O_2 $ systems were studied using 3-methylcholanthrene-pretreated rat liver microsomes. The maximal rate of B(a)P hydroxylation at constant concentration ($80\;{\mu}M)$ of the substrate was observed in the presence of $30\;{\mu}M$ CuOOH. However, at concentrations higher than $30\;{\mu}M$ CuOOH the hydroxylation rates were rapidly decreased. In contrast to CuOOH, at a concentration of $200\;{\mu}M$ NADPH, B(a)P hydroxylation rate reached a plateau. At concentrations higher than $200\;{\mu}M$ NADPH, the rates of substrate hydroxylation were maintained at the maximal rate with no inhibition. Acetone at 1% (v/v) enhanced both CuOOH- and NADPH/$O_2$-supported B(a)P hydroxylation at the optimal concentrations of the cofactors. At concentrations higher than 1% (v/v) acetone, substrate hydroxylation was sterero specific under the support of these two cofactors; it was strongly enhanced with $30\;{\mu}M$ CuOOH, but rather inhibited in the $200\;{\mu}M$> NADPH/$0_2 $ system. The lipid peroxidation rate induced during CuOOH-supported P450-dependent B(a)P hydroxylation was increased as CuOOH concentrations were increased. Acetone in the concentration range of 2.5~7.5%(v/v) inhibited lipid peroxidation during CuOOH supported B(a)P hydroxylation. The finding that CuOOH-supported B(a)P hydroxylation is greatly enhanced by acetone suggests that acetone may contribute more to the activation of oxygen (for the insertion of oxygen into the substrate) in the presence of CuOOH than with NADPH/$O_2$. Acetone may also contribute to the partial inhibition of destruction of microsomal membranes by lipid peroxidation.

• Biomolecules & Therapeutics
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• 제23권2호
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• pp.201-206
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• 2015

Scutellaria baicalensis is one of the most widely used herbal medicines in East Asia. Because baicalein and baicalin are major components of this herb, it is important to understand the effects of these compounds on drug metabolizing enzymes, such as cytochrome P450 (CYP), for evaluating herb-drug interaction. The effects of baicalin and baicalein on activities of ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), benzyloxyresorufin O-debenzylase (BROD), p-nitrophenol hydroxylase and erythromycin N-demethylase were assessed in rat liver microsomes in the present study. In addition, the pharmacokinetics of caffeine and its three metabolites (i.e., paraxanthine, theobromine and theophylline) in baicalin-treated rats were compared with untreated control. As results, EROD, MROD and BROD activities were inhibited by both baicalin and baicalein. However, there were no significant differences in the pharmacokinetic parameters of oral caffeine and its three metabolites between control and baicalin-treated rats. When the plasma concentration of baicalin was determined, the maximum concentration of baicalin was below the estimated $IC_{50}$ values observed in vitro. In conclusion, baicalin had no effects on the pharmacokinetics of caffeine and its metabolites in vivo, following single oral administration in rats.

• 한국균학회지
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• 제29권1호
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• pp.67-71
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• 2001

민간약재로 사용되어지는 아카시재목 버섯(Fomitella fraxinea) 자실체의 에탄올 추출물로부터 ethyl acetate 추출, silica gel chromatography, preparative TLC 등의 방법으로 항산화 활성을 나타내는 steroid계 화합물, F-1을 분리 정제하였다. EI-Mass, FT-IR, $^1H$ 및 $^{13}C$ NMR 등 기기 분석에 의하여 F-1은 분자량이 412.65, 분자식이 $C_{28}H_{44}O_2$의 steroid 화합물, ergosta-7,22-diene-3-one-$16{\beta}-ol$임을 확인하였다. F-1의 지질과산화 저해활성은 $10^{\mu}g/ml$의 농도에서 86%의 지질과산화 저해활성을 나타내었으며, $IC_{50}$ 값은 $3.8{\mu}g/ml$이었다. 이 화합물은 항산화제인 ${\alpha}-tocoperol$과 유사한 항산화 활성을 나타내었다.

• KSBB Journal
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• 제15권2호
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• pp.150-155
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• 2000

본 연구는 Streptomyces sp. BH-405의 배양액으로부터 유기용매로 추출하여 지질과 산화에 대한 항산화 효과를 실험하였다. Streptomyces sp. BH-405의 배양액을 ethylether로 추출한 후 silica gel column(100$\times$10 cm) chromatography로 분획한 획분을 POV로 측정한 결과 fraction 3에서 향산화 활성이 가장 높았다. 항산화 활성이 높은 fraction 3 획분을 다시 preparative TLC와 column chromatography로 더욱 정제하여 band 2를 얻었다. Band 2의 항산화 효과를 알아보기 위해 기존의 항산화제와 비교한 결과 이-$\alpha$-tocopherol, BHA보다 산화억제 효과가 높았으며 DPPH에 의한 수소 공여능은 실험결과가 우수하였다. 한편 band 2는 쥐 간의 microsome에 있어서 유리기의 소거기능이 있었고 NADPH 및 Fenton 시액에 위한 효소적 과산화 지질의 생성을 억제하였다. 그리고 mitochondria와 리놀산의 과산화 유도계에서도 지질의 과산화 과정에 생성하는 유리기의 형성을 차단하였다. 결론적으로 Streptomyces sp. BH-405의 배양액에서 얻은 획분인 band 2는 산화를 억제하는 활성이 있었다.

• Journal of Ginseng Research
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• 제43권4호
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• pp.539-549
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• 2019

Background: 20(S)-Protopanaxadiol (PPD), the aglycone part of 20(S)-protopanaxadiol ginsenosides, possesses antidepressant activity among many other pharmacological activities. It is currently undergoing clinical trial in China as an antidepressant. Methods: In this study, an ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass tandem mass spectrometry method was established to identify the metabolites of PPD in human plasma and urine following oral administration in phase IIa clinical trial. Results: A total of 40 metabolites in human plasma and urine were identified using this method. Four metabolites identified were isolated from rat feces, and two of them were analyzed by NMR to elucidate the exact structures. The structures of isolated compounds were confirmed as (20S,24S)-epoxydammarane-12,23,25-triol-3-one and (20S,24S)-epoxydammarane-3,12,23,25-tetrol. Both compounds were found as metabolites in human for the first time. Upon comparing our findings with the findings of the in vitro study of PPD metabolism in human liver microsomes and human hepatocytes, metabolites with m/z 475.3783 and phase II metabolites were not found in our study whereas metabolites with m/z 505.3530, 523.3641, and 525.3788 were exclusively detected in our experiments. Conclusion: The metabolites identified using ultra-performance liquid chromatography coupled with triple quadrupole time-of-flight mass spectrometry in our study were mostly hydroxylated metabolites. This indicated that PPD was metabolized in human body mainly through phase I hepatic metabolism. The main metabolites are in 20,24-oxide form with multiple hydroxylation sites. Finally, the metabolic pathways of PPD in vivo (human) were proposed based on structural analysis.

• BMB Reports
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• 제32권3호
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• pp.232-238
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• 1999

Sex differences in the induction of microsomal cytochrome P-450 (CYP) and the activities of several related enzymes of Sprague-Dawley rats treated with 1-bromopropane (1-BrP) were investigated. Male and female rats were exposed to 50, 300, and 1800 ppm of 1-BrP per kg body weight (6 h a day,S days a week, 8 weeks) by inhalation. The mean body weight of 1-BrP treated groups increased according to the day elapsed, but four and five weeks respectively after the start of the exposure, the mean body weight of male and female rats had significantly reduced in the group treated with 1800 ppm 1-BrP compared with the control group (p<0.01). While the relative weights of liver increased in both sexes, statistical significance in both sexes was found only in the group receiving 1800 ppm/kg of 1-BrP (p<0.01). The total contents of CYP, $b_5$, NADPH-P-450 reductase, NADH $b_5$ reductase, ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-dealkylase (PROD), and p-nitrophenol hydroxylase (pNPH) activities were examined for the possible effects of 1-BrP. No significant changes in the CYP and $b_5$ contents, NADPH-P-450 reuctase, NADH $b_5$ reductase, ethoxyresorufin-O-deethylase (EROD), and pentoxyresorufin- O-dealkylase (PROD) were observed between the control and treated groups. The activity of pNPH increased steadily with the increase in the concentration of 1-BrP in both sexes, but was significantly increased only in the 1800 ppm-treated group of male rats (p<0.05). When Western blottings were carried out with three monoclonal antibodies (MAb 1-7-1, MAb 2-66-3, and MAb 1-98-1) which were specific against CYP1A1/2, CYP2B1/2, and CYP2E1, respectively, a strong signal corresponding to CYP2E1 was observed in microsomes obtained from rats treated with 1-BrP. Glutathione S-transferase (GST) activity and the content of lipid peroxide significantly increased in the treated groups compared with the control group (p<0.05). These results suggest that 1-BrP can primarily induce CYP2E1 as the major form and that GST phase II enzymes play important roles in 1-BrP metabolism, showing sex-dependence in the metabolic mechanism of 1-BrP in the rat liver.

• 한국식품과학회지
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• 제32권3호
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• pp.726-735
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• 2000

목질진흙버섯 자실체와 배양 균사체의 열수추출 및 열수 추출물의 에탄올, UF처리 분획들에 대한 약리 효과를 조사하여 다음과 같은 결과를 얻었다. Sarcoma 180 암세포 증식 저지율은 자실체 열수 총 분획(Fr. I)보다 비교적 고분자인 다당류 분획(Fr. II, Fr. III, Fr. IV)에서 $80.4{\sim}85.9%$로 높게 나타났다. 면역계에 미치는 영향으로 보체계 활성화는 $10.1{\sim}13.6%$, 대식세포의 NO 생성능은 자실체 및 균사체 모든 분획에서 생성되었으며, $TNF-{\alpha}$생성능은 NO 생성능이 높았던 분획들에서 높은 생성능을 나타내었다. 효소적 및 비효소적 지질과산화 유발에 대한 영향은 목질진흙버섯 자실체와 배양 균사체의 모든 분획에서 지질 과산화 억제능을 나타내었고, 유리기 제거능에 있어서는 농도의존적으로 효과가 있는 것으로 나타났으며, DPPH에 대한 Fr. III의 $SC_{50}$은 $32.0\;{\mu}g/mL$로 조사되었다. 상기와 같은 결과들로부터 목질진흙버섯 자실체와 배양 균사체의 열수추출 및 열수 추출물의 에탄올, UF처리 분획들은 항암활성, 면역활성, 지질 과산화 억제효과 및 유리기 제거능이 있음을 확인할 수 있었다.

• 대한지역사회영양학회지
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• 제2권5호
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• pp.735-744
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• 1997

The effect of green tea drinking on the hepatocellular chemical cacinogenesis have been studied. Placental glutathione S-transferase(GST-P) positive foci area in a liver tissue, contents of thiobarbituric acid reactive substances(TBARS), total cytochrome P450 and glucose 6-phospphatase(G6P) activity in hepatic microsomes were investigated. Weaning Sprague-Dawley male rats were fed AIN-76A diet with deionized water or green tea infusion, Rats of CTR and CTR+ groups were provided deionized water while GTI and GTI+ groups were provided green tea instead of deionized water for the entire experimental period of 13weeks. Rats of GTP and GTP + groups had deionized water for the first 6 weeks and switched to green tea for the last 7weeks of the experimental period. CTR+, GTI +, and GTP + groups were carcinogen treated groups, Diethylnitrosamine(DEN) was injected as a single dose of 200mg/kg body weight intraperitoneally after 4 weeks of feeding. 2-Acetyla-minofluorene(AAF) was used as a carcinogen proliferater and suppled in the diets of carcinogen treated rats as 0.02% content for the last 6weeks starting from 2weeks after DEN injection. Rats were sacrificed after 13week weeks of feeding. The area and number of GST-P positive foci detected in carcinogen treated rats were decreased by green tea ingestion but when timing and duration of green tea ingestion was delayed after promotion period as in GTP + group, GST-P positive foci were not decreased as much as in GTI+ group. TBARS contents of carcinogen treated rats decreased by 13weeks of green tea ingestion but GTP groups did not show statiscally significant differences. G6P activities tended to decrease by carcinogen treatment but changes were not statiscally significant by green tea ingestion. Total cytochrome P450 contents were increased by carcinogen treatment. Thirteen weeks of green tea ingestion (GTI) also increased to total cytochrome P450 contents while 7weeks of green tea ingestion(GTP) did show any effects. These results suggest that green tea has suppressive effects on hepatocellular chemical carcinogenesis probably through the activities of antioxidant compounds. (Korean J Community utrition 2(5) : 735∼744, 1997)

• Journal of Preventive Medicine and Public Health
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• 제32권1호
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• pp.88-94
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• 1999

이 연구는 DMF에 의한 간독성 기전을 알아보기 위하여, 대사과정에서 중요한 역할을 하는 이물질 대사효소와 그와 관련된 효소가 어떠한 변화를 보이는가를 알아보았다. 이 연구에 사용된 동물은 Sprague Dawley계 수컷 흰쥐로 DMF를 체중 kg당 0(Control), 450 (D1), 900 (D2), 1,800 (D3) mg을 1일 l회씩 3일간 연속하여 복강주사하였다. 마지막 투여 후 24시간 후에 실험동물로부터 간장의 microsome을 분리하였고, P450 동위효소의 유도와 P450의존성 촉매 효소의 활성도 변화를 관찰하였다. 연구결과, DMF를 투여한 실험군이 대조군보다 microsomal 단백질 함량이 통계학적으로 유의하지는 않았지만 낮은 수치를 보였다. P450과 b5 함량 역시 대조군과 투여군간에 유의한 차이가 없었다. 대사과정에서 어떠한 전자전달계가 주로 관여하는지를 알아보았는데, NADPH-P450 reductase의 경우 대조군보다 투여군이 투여용량이 증가함에 따라 활성도가 유의하게 증가하였다(p<0.01). NADH-b5 reductase의 활성도 의 경우는 대조군보다 투여군이 감소하여(p<0.01), 전자전달이 주로 NADPHP-450 reductase에 의해 이루어지는 것을 알 수 있었다. 활성도 측정에서는 EROD 와 PROD 활성도는 유의한 차이를 보이지 않았으나 pNPH 활성도는 처리군에서 현저한 증가가 관찰되었다(p<0.01). 또한 P4501A1/2, P4502B1/2 및 P4502E1에 대한 단세포군 항제를 이용한 Western immunoblot 분석에서 P4502E1 단백질 의 양이 현저하게 증가하였다. 이 상의 결과를 보면, DMF에 의해서 P4502E1 형태의 동위효소가 유도되며, 유도된 P4502E1 동위효소가 DMF의 대사에 관여하는 것으로 보인다.

• 생명과학회지
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• 제15권5호
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• pp.819-825
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• 2005

항산화물질인 glutathione (${\gamma}$-L-glutamyl-cysteinyl-glycine) 고함유 효모 Saccharomyces cerevisiae FF-8에서 생산된 glutathione을 함유한 세포 추출액의 항산화 활성을 in vitro 과산화지질 실험계인 DPPH($a,{\;}\acute{a}-diphenyl-\beta-picrylhydrazyl$)법, linoleic acid를 이용한 ferric thiocyanate법과 TBA법 및 microsome 생체막 지질 과산화물 생성정도의 TBARS법으로 측정하였다. YM 최적 배지에서 생산된 glutathione 농도는 $204\mug/ml$로 YM 기본배지에서 생산된 glutathione 농도 $74\mug/ml$보다 2.76배 증가하였다. 본 실험에서는 YM 기본배지와 최적배지에서 S. cerevisiae FF-8이 생산하는 glutathione 함량에 따른 항산화 활성을 비교하였다. DPPH 측정법에서는 짙은 자색의 탈색되는 정도로 나타내는 전자 공여능이 glutathione 함량이 높은 최적 생산배지에서 S. cerevisiae FF-8가 생산하는 glutathione고함유 세포 추출액에서 대조구인 $ 0.05\%BHT $와 비슷한 수준으로 항산화 활성이 높게 나타났다. 각 조직 microsome을 이용한 생체막 지질 과산화 억제정도는 최적 생산배지에서 전체적으로 높게 나타났으며, 간장 $60.98\%$, 신장 $56.43\%$, 심장 $52.91\%$, 뇌 $52.13\%$, 고환$45.57\%$ 및 비장 $42.95\%$순으로 나타났다 Linoleic acid 산화 실험계를 이용한 ferric thiocyanate법에서는 최적 생산배지가 반응 7일째까지 대조구에 비해 강한 항산화 활성을 보였으며, TBA법에서는 반응 5일째까지 최적 생산배지가 YM 배지보다는 높은 항산화 활성을 나타내었다 이상의 결과에서 Saccharomyces cerevisiae FF-8 균주가 glutathione을 생산하는 최적배지 조건에서 생산된 glutathione 고함유 세포 추출액은 in vitro 항산화 실험계인 DPPH radical scavenging activity, ferric thiocyanate and TBARS 측정에서 항산화 활성을 나타내는 생리활성 성분을 지닌 것으로 나타나 천연 항산화제로서의 사용 가능성을 시사하였다.