• Preventive Nutrition and Food Science
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• v.4 no.4
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• pp.221-225
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• 1999

Antioxidative compounds contained in roasted safflower seeds were investigated. Six phenolic compounds, N-feruloylserotonin, N-(p-coumaroyl) serotonin, matairesinol, 8'-hydroxyarctigenin, acacetin 7-Ο-β-D-glucoside(tilianine) and acacetin were isolated and identified from the extract of seeds. The inhibitory effects of six phenolic compounds on 1,1-dipheny1-2-picrylhydrazyl(DPPH) radical and lipid peroxidation induced by H₂O₂/FeSO₄in rat liver microsomes were determined. Two serotonins showed more potent DPPH radical scavenging activity, and a stronger inhibitory effect on the lipid peroxidation than that of α-tocopherol. In addition, acacetin and matairesinol also considerably inhibited lipid peroxidation, while 2-hydroxy-arctigenin and tilianine were inactive. These results suggest that phenolic compounds, including serotonins, lignans and flavonoids in the roasted safflower seeds can be used as potential dietary natural antioxidants.

• Toxicological Research
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• v.9 no.1
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• pp.35-44
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• 1993

Role of rat cytochrome P-450 2E1(P-450 2E 1) in the metabolism of chlorzoxazone was examined by using several approaches' (1) selective inhibiton of catalytic activity in rat liver microsomes by diethyldithiocarbamate, (2) correlation of dimethylnitrosomine N-demethylation with chlorzoxazone 6-hydroxylation, and (3) immunoinhibition of catalytic activity with rabbit anti-rat P-450. The results indicated that P-450 2E1 is responsible for the metabolism of chlorzoxazone.

• Bulletin of the Korean Chemical Society
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• v.20 no.7
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• pp.819-823
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• 1999

Antioxidant activities of various mushroom fruiting bodies were investigated in vitro. Among the mushroom extracts examined, Armillariella mellea, Daedalea dickinsi, Fomitella fraxinea and Pleurotus cornusopiae markedly exhibited inhibition on lipid peroxidaton of rat liver microsomes. Ergosterol peroxide (5,8-epidioxy-5α,8α-ergosta-6,22E-dien-3β-ol), antioxidant from A. mellea, was isolated by solvent extraction, silica gel column chromatography and recrystallization. The structure of the compound was determined by NMR, GC/MS and X-ray crystallography. Ergosterol peroxide showed potent inhibition on lipid peroxidation and exhibited higher antioxidant activity than well-known antioxidants, α-tocopherol and thiourea.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.81.1-81.1
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• 2003

Buprenorphine(BPN) is used to treat withdrawal syndromes in narcotic addictions. When narcotics are stopped, withdrawal syndromes such as pupil dilation and blood pressure increment are appeared. And BPN is often prescribed concomitantly with antihypertensives. We researched whether combined medicines of BPN and antihypertensives affected on the metabolism of BPN. After BPN was incubated with antihypertensives such as nifedipine, verapamil, captopril and propranolol in rat or human microsomes, amounts of BPN and its metabolite, norbuprenorphine (NBPN), were measured. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.112.2-112.2
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• 2003

CYP1 enzymes, CYP1A1, CYP1A2 and CYP1B1, are known to bioactivate procarcinogens particularly polyaromatic compounds. Flavonoids are a class of natural compounds that are present in edible plants. Structurally, these compounds are polyphenols with two aromatic rings (A, B) and a heterocycyclic ring (C). We observed the differential inhibition of 5,7-dihydroxyflavones which are different in numbers of B-ring-OH, to the activity of ethoxyresorufin O-deethylase (EROD) in human hepatic microsomes with the IC50 values, ie, 0.57 mM, 1.28 mM, and 3.62 mM, chrysin, apigenin, and Luteolin, respectively. (omitted)

• Mass Spectrometry Letters
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• v.14 no.1
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• pp.1-8
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• 2023

Eutylone, dibutylone, and dimethylone are potential psychotropic designer drugs. The purpose of this study was to investigate the in vitro metabolic pathways of synthetic cathinones with methylenedioxy groups. The three methylenedioxy derivatives were incubated with human liver microsomes. The metabolites were characterized based on liquid chromatography and quadrupole-time-of-flight mass spectrometry. Eutylone, dibutylone, and dimethylone were metabolized to yield three, six, and four metabolites, respectively. Reduction and demethylenation were the major metabolic pathways for all three drugs tested. However, dibutylone and dimethylone showed an additional metabolite generated via N-oxidation. These results provide evidence for the in vivo metabolism of methylenedioxy synthetic cathinones, and could be applied to the analysis of synthetic cathinones and their relevant metabolites in biological samples.

• Journal of Nutrition and Health
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• v.35 no.3
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• pp.291-295
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• 2002

This study was designed to investigate the effects of a butanol (BuOH) fraction from an extract of pine (Pinus densiflora Sieb et Zucc.) needles, on oxygen radicals and their scavenger enzymes in the liver membranes of rats. Twenty-eight male Sprague-Dawley (SD) rats were divided into four groups over a 45 days study period: the control group on a basic diet, and three experimental groups on three different dietary levels of the butanol fraction, specifically 25 mg (BuOH-25), 50 mg (BuOH-50), and 100 mg (BuOH-100) butanol fraction/kg body weight/day, thereby 0.025%, 0.05%, 0.1% of butanol extract of pine needles was added to basil diet respectively. At the end of the experimental period, body weights and food intakes were not different among the four groups. The results showed that cholesterol accumulation in the mitochondria and microsomes of liver cells was significantly inhibited in the BuOH-50 and BuOH-100 groups: by 11.6% and 20.1% in the mitochondria of the BuOH-50 and BuOH-100 groups, respectively; and by 10.5%, and 13.5% in the microsomes of the BuOH-50 and BuOH-100 groups, respectively, compared with the control group. The levels of hydroxyl radicals (.OH) were significantly) lower in the liver mitochondria of the BuOH-50 and BuOH-100 groups (by 13.3% and 18.5%, respectively), while OH radicals were significantly lower in the microsomes or all three experimental groups (by 15.7% in the BuOH-25 group, 20.0% in the BuOH-50 group, and 20.6% in the BuOH-100group), compared with the control group. Superoxide radical (O$_2$) formation was also significantly inhibited in the liver cytosol of both BuOH-50 and BuOH-100 groups; the levels of these radicals were 8.0% lower for the BuOH-50 group and 11.1% lower for the BuOH-100 group, compared to the control group. Copper/Zinc - superoxide dismutase (Cu/Zn-SOD) activities were significantly increased (by 10.3% and 15.9%, respectively) in the liver cytosols of the BuOH-50 and BuOH-100 groups, but Mn-SOD activities were almost identical in the three RuOH groups, compared with the control group. Glutathione peroxidase (GPx) activities were significantly increased in the three experimental groups (by 9.0% in the BuOH-25 group, 19.4% in the BuOH-50 group, and by 25.6% in the BuOH-100 group), compared with the control group. These results suggest that the butanol extract of pine needles may play an effective role in attenuating oxygen radicals and activating scavenger enzymes; consequently, aging may be very effectively modulated and/or inhibited.

• Applied Biological Chemistry
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• v.39 no.3
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• pp.189-194
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• 1996

The effects of scorpion (Leiurus quinquestriatus hebraeus, Lqh) venom were evaluated on the activities of microsomal $Ca^{2+}-ATPase$ and $Ca^{2+}$ release channel prepared from the epithelial cells of pig airway. Whole venom of Lqh $(120\;{\mu}g/ml)$ increased the activity of microsomal $Ca^{2+}-ATPase$ about 32% in the tight-sealed microsomes and about 28% in the Triton X-100-treated or $Ca^{2+}$ ionophore A23187-treated leaky microsomes. Thapsigargin, a specific antagonist of $Ca^{2+}-ATPase$, inhibited 42% of total ATPase activity and also completely blocked the effects of Lqh venom, suggesting that Lqh venom directly activiates the microsomal $Ca^{2+}-ATPase$. In order to determine if Lqh venom increases the microsomal uptake of $^{45}Ca^{2+}$, Lqh venom was added in the uptake medium. The Lqh venom increased microsomal $^{45}Ca^{2+}$ uptake up to ${\sim}20%$ and the increase was only observed when heparin, an antagonist of $InsP_3$ receptor channel, was added in the uptake medium. Lqh venom in the absence of heparin unexpectedly decreased the rate and the amount of $^{45}Ca^{2+}$ uptake. These results were explained by simultaneous increases in $^{45}Ca^{2+}$ release as well as $^{45}Ca^{2+}$ uptake by Lqh venom. Lqh venom itself increased the release of $^{45}Ca^{2+}$ as much as $^{45}Ca^{2+}$ release by $4\;{\mu}m\;InsP_3$, implying that Lqh venom also activates $InsP_3$ receptor, microsomal $Ca^{2+}$ release channel. Based on these results, we suggest that the Lqh venom consists of at least two components; one activates the $InsP_3$ receptor and the other avates the $Ca^{2+}-ATPase$. Currently we a investigating the chemical and electrophysiological properties of the active components of Lqh venom.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.1
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• pp.73-79
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• 2009

This study was undertaken to investigate the effects of single and combined exposure of toluene (T) and xylene (X) on the cytochrome-450(CYP)-mediated metabolizing capacity, induction of CYP isozymes and the excretion of their metabolites in urine. Animal were adults male Sprague-Dawley (SD) rats and divided into 4 groups such as control, T (treated with 63.7 mg/body kg), X (treated with 65.9 mg/body kg) and TX(T=X). Organic solvents was administrated by intraperitoneal injection for 3 days. The contents of protein and CYP in liver microsomes of control group were $16.48{\pm}0.56 mg/m{\ell}$ and $0.744{\pm}0.025$ nmol/mg protein, respectively, and they contents were significantly lower than in derived from treated groups (p<0.01). The activities of PROD and ${\rho}NPH$ were significantly higher in single treated groups than in control and combined group (TX). When Western immunoblotting were carried out with two monoclonal antibodies (MAb 1-98-1 and MAb 2-66-3) which were specific against CYP2B1/2 and CYP2E1, respectively, a strong signal corresponding to CYP2B1/2 was observed in microsomes obtained from rats treated with X and TX. The color density against CYP2E1 was slightly increased in T and TX groups compared with C and X groups. The amounts of urinary hippuric acid in T single treated group was $3.29{\pm}1.97$ g/g creatinine and TX combined group was $2.91{\pm}1.76$ g/g creatinine, but was not significant. However, amount of urinary methy hippuric acid in X single treated group ($1.62{\pm}0.72$ g/g creatinine) was significantly higher than TX combined group ($0.93{\pm} 0.63$ g/g creatinine)(p<0.01). These results suggested that CYP2E1 isozyme might be responsible for the metabolism of T, and CYP2B1/2 isozyme is for X. And also, difference of metabolites level between single and combined group may be speculated that the intermediates of T and X interacted each other in the process of their metabolite formation reaction.

• Environmental Mutagens and Carcinogens
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• v.17 no.2
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• pp.97-108
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• 1997

The drugs or xenobiotics introduced to the body, are detoxified through the process of biotransformation in the body. In this process, most of the insoluble compounds become more polar, soluble and easily excretable. But, parts of introduced materials are metabolized to highly reactive electrophilic carcinogens through activation pathways. These metabolites are toxic and can react with DNA, RNA and proteins which are nucleophilic compounds. The objective of this study is to illustrate the aleactivation pathways of two highly reactive epoxide compounds, vinyl carbamate epoxide (VCO) and 2'-(4-nitrophenoxy)oxirane (NPO). They are the ultimate electrophilic carcinogens of ethyl carbamate(urethane) and 4-nitrophenyl vinyl ether, respectively. In this research, we studied the inhibition of the mutagenic activities of VCO or NPO by nuchieophiles [glutahione(GSH) and N-acetylcysteine(NAC)], detoxifying enzymes[epoxide hydrolase and glutathione-S-transferase(GST)] and intracellular organelles (microsomes and cytosol). In addition we also tested the suppression of DNA adducts formation by GSH and NAC. The results are summerized as follow. 1. The microsomes and cytosol which contain epoxide hydrolase and GST, respectively, decreased the mutagenicity of VCO (74% and 95%, respecfivel), and NPO (35% and 93%, respectively). The nucleophilic GSH and NAC decreased the mutagenicity by 86% (VCO) and 80% (NPO), 76% (VCO) and 40% (NPO), respectively. 2. The purified epoxide hydrolase decreased the mutagenicity of two epoxides in a dose-dependent manner, and GSH also decreased the mutagenicity in the presence of GST. 3. Formation of two DNA adducts, 7-(2'-oxoethyi)guanine (OEG) and N2,3-ethenoguanine(EG), were compared in the presence of calf thymus DNA and epoxide (VCO or NPO) in vitro system. The amounts of DNA adducts were decreased in the presence of GSH (25% and 29% in VCO, 32% and 29% in NPO), and NAC (14% and 16% in VCO, 21% and 11% in NPO), respectively. From these results, it is concluded that the ultimate carcinogenic metabolites, VCO and NPO, can be made in the body, but much of them may be inactivated and detoxified by the nucleophilic GSH, NAC and detoxifying enzymes (epoxide hydrolase and GST). Therefore, by these mechanism, the formation of DNA adducts and mutagenic activities of these two epoxides may be lowered in vivo.