• Biomedical Science Letters
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• v.9 no.2
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• pp.75-84
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• 2003

To evaluate the influence of hepatic oxygen free radical systems on liver injury by topical p-phenylenediamine (PPD) application on rat skin, PPD (25 mg/16.5 $\textrm{cm}^2$) was topically applied to the abdominal region 5 times every other day and sacrificed. By PPD treatment, increasing rate of liver weight/body weight (%), serum activities of alanine aminotransferase and aspartate aminotransferase and decreasing rate of microsomal glucose-6-phosphatase activity were higher in the rats fed tungstate supplemented diet than those fed a standard diet. These findings indicate that group fed tungstate supplemented diet have more severe liver injury compared with group fed standard diet on topical PPD application. However, the activities of oxygen free radical generating enzymes such as xanthine oxidase (XO) and cytochrome P450 dependent aniline hydroxylase and those of oxygen free radical scavenging enzymes were not found to be different between these two animal groups. In the present study, a novel monitoring method to detect the generating of oxygen free radicals in liver extract was devised. Throughout this method, the oxidized PPD produced by oxygen free radicals was determined colorimetrically. The increasing rate of PPD oxidation by liver homogenate was higher in tungstate fed animals than in standard diet fed ones. Among the fractionations of liver extract, the mitochondrial and postmitochondrial fractions in the liver extract of tungstate fed animals led to a higher availability of PPD oxidation by PPD treatment compared with standard diet fed ones. In conclusion, these results suggest that an enhanced liver injury in tungstate fed animals treated with PPD may be due to oxygen free radicals produced in other systems except oxygen free radicals generating from cytosolic XO system. Especially, oxidative availability by PPD can be used for oxygen free radical detection in some tissue.

• The Journal of Korean Medicine
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• v.42 no.4
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• pp.10-24
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• 2021

Objectives: Yongdamsagan-tang (YST) and Paljung-san (PJS) in traditional medicine and finasteride in modern medicine are used to treat benign prostatic hyperplasia (BPH). In recent, the use of combination herbal remedies with conventional drugs has been increasing. Therefore, we investigated the anti-inflammatory effects of these drugs to treat BPH and the influence of herbal formulas on finasteride metabolism. Methods: The inhibitory effects of the herbal formulas and finasteride on the production of inflammatory mediators and cytokines were determined in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Additionally, the influence of herbal formulas on activities of human drug metabolizing enzymes (DMEs) was assessed using human microsomal enzymes. Results: We observed that YST, PJS and finasteride inhibited the production of nitric oxide (NO), prostaglandin E₂ (PGE₂) and interleukin-6 (IL-6) in RAW 264.7 cells. The half maximal inhibitory concentration (IC₅₀) of YST on PGE₂ production was calculated to be below 25 ㎍/mL. YST inhibited the activity of uridine diphosphate-glucuronosyltransterase (UGT) 1A4 with an IC₅₀ value of 49.35 ㎍/mL. The activities of cytochrome P450 (CYP) 1A2, CYP2B6, CYP2C19, CYP3A4, and UGT1A1 were inhibited by PJS (IC₅₀ < 100 ㎍/mL, each). Although PJS and YST inhibited the activities of CYP3A4 and UGT1A4, respectively, these formulas may not influence the metabolism of finasteride because the IC₅₀ values of herbal formulas on DMEs are too high to affect metabolism. Conclusions: Our results suggest that the combination of finasteride and YST or PJS might not influence their drug metabolism and that the drugs may have synergistic effects against BPH.

• YAKHAK HOEJI
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• v.59 no.2
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• pp.59-65
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• 2015

KR-67500, trans-4-(2-(4-methyl-1,1-dioxido-6-(2,4,6-trichlorophenyl)-1,2,6-thiadiazinan-2-yl)acetamido)adamantane-1-carboxamide, is a novel $11{\beta}$-HSD1 inhibitor with its therapeutic effects of its anti-diabetic, anti-adipogenic and anti-osteoporotic activity. This study was performed to evaluate in vitro and in vivo pharmacokinetic properties of KR-67500 as a new drug candidate. KR-67500 was stable and highly bound to proteins in rat plasma. The microsomal stabilities of KR-67500 in human and rat liver were high. The inhibitory effect of KR-67500 for five cytochrome P450 enzymes was low. Preclinical pharmacokinetic studies have been carried out with intravenous or oral administrations of KR-67500 (10 mg/kg) to male rats and monkey. KR-67500 showed low clearance (0.68 l/h/kg) and high oral bioavailability (102%) in male rats. These results suggest that KR-67500 has good drug-like pharmacokinetic properties with a low first-pass effect and high bioavailability for an oral therapeutic agent of diabetes and osteoporosis.

• Environmental Analysis Health and Toxicology
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• v.14 no.3
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• pp.87-93
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• 1999

Antioxidative and scavenging effects were investigated by using two hyaroxycinnamic acids (caffeetannins). such as caffeic acid and chlorogenic acid, on oxidative stress and hepatotoxicity that induced by paraquat. The results are summerized as follows: 1. To assess radical scavenging ability, reduction concentration (IC$\sub$50/) of 1.1 diphenyl-2-dipicrylhydrazine (DPPH) were measured. IC$\sub$50/ values of caffeic acid and chlorogenic acid were 29.7 ${\pm}$0.6 ${\mu}$M and 26.0${\pm}$0.5 ${\mu}$M respectively. Their radical scavenging activities showed concentration-dependent manner. 2. In H$_2$O$_2$-induced hemolysis assay to rat blood, caffeic acid and chlorogenic acid led to different effects, whose hemolysis inhibition ratios at 100 ${\mu}$M were 45.2${\pm}$7.1% and 11.6${\pm}$3.1% respectively 3. In hypoxanthine-xanthine oxidase system producing superoxide anion, caffeic acid and chlorogenic acid showed different inhibitory activities of xanthine oxidase showing 36.8${\pm}$4.3% and 5.4${\pm}$2.3% respectively. 4. To microsomal NADPH dependent cytochrome p-450 reductase in rat liver, paraquat consumed NADPH at a dose-dependent manner from 0 to 1 ${\mu}$M paraquat concentration. Caffeic acid and chlorogenic acid blocked NADPH consumption rates at concentration-dependent manner and inhibition ratios at 100 ${\mu}$M were 67.6% and 59.2% respectively. 5. Administration (30mg/kg, iv) of paraquat to rats caused the marked elevation of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and lipid peroxides (LPO) in the serum and lipid peroxides in the microsome as compared to the control group. Serum GOT, GPT, LDH, ALP and LPO and liver microsomal LPO were reduced significantly by caffeic acid (50mg/kg), chlorogenic acid (25mg/kg) and silymarin (150 mg/kg) as compared to the paraquat group. From these results, caffeic acid and chlorogenic acid exerted their antioxidative agents by removing reactive oxygen substance (ROS) and scavenging effects by inhibiting ROS generating enzyme. As a general, two hydroxyeinnamic acids showed the useful compounds for scavenger and reducer on the paraquat induced hepatotoxicity.

• Preventive Nutrition and Food Science
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• v.19 no.4
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• pp.268-273
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• 2014

The induction of detoxification enzymes by benzyl isothiocyanate (BITC) and its synthetic N-acetyl-L-cysteine (NAC) conjugate (NAC-BITC) was examined in Hepa1c1c7 murine hepatoma cells. BITC and NAC-BITC inhibited Hepa1c1c7 cell growth in a dose-dependent manner. Cell growth was 4.5~57.2% lower in Hepa1c1c7 cells treated with $0.1{\sim}1.0{\mu}M$ BITC than in control-treated Hepa1c1c7 cells. The NAC-BITC treatment had a similar inhibitory pattern on Hepa1c1c7 cell growth; $0.5{\mu}M$ and $10{\mu}M$ NAC-BITC decreased cell growth by 13.6% and 47.4%, respectively. Treatment of Hepa1c1c7 cells with $0.1{\sim}2.0{\mu}M$ BITC also elicited a dose-response effect on the induction of quinone reductase quinone reductase (QR) activity and QR mRNA expression. Treatment with $1{\mu}M$ and $2{\mu}M$ BITC caused 1.8- and 2.8-fold inductions of QR mRNA, respectively. By comparison, treatment with $1{\mu}M$ and $2{\mu}M$ NAC-BITC caused 1.6-and 1.9-fold inductions of QR mRNA, respectively. Cytochrome P450 (CYP) 1A1 and CYP2E1 induction were lower in $0.1{\sim}2{\mu}M$ BITC-treated cells than in control-treated cells. CYP2E1 activity was 1.2-fold greater in $0.1{\mu}M$ NAC-BITC-treated cells than in control-treated cells. However, the CYP2E1 activity of cells treated with higher concentrations (i.e., $1{\sim}2{\mu}M$) of NAC-BITC was similar to the activity of control-treated cells. Considering the potential of isothiocyanatesto prevent cancer, these results provide support for the use of BITC and NAC-BITC conjugates as chemopreventive agents.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.57-61
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• 2001

Conjugated linoleic acid (CLA), when incorporated into mouse liver microsomal membranes, selectively inhibits the mutagenesis of 2-amino-3-methylimidazo[4,5-f] quinoline (IQ). Nine-week old female ICR mice were given (p.o.) 0.1 mL olive oil alone (control), 0.1 mL olive oil plus 0.1 mL linoleic acid, or 0.1 mL olive oil plus 0.1 mL CLA, twice weekly for four weeks. The animals were then sacrificed and liver S-9 fractions were prepared. Activation of IQ for mutagenesis by the liver S-9 from CLA-treated mice was significantly reduced in comparison wit liver S-9 from control or linolic acid-treated mice. By contrast, the activation of 7,12-dimethylbenz[a] anthracene (DMBA) and benzo[a] pyrene (BP) was unaffected. Hence, CLA incorporated into phospholipids may selectively affect cytochrome P450 isozymes responsible for activating IQ, but not those which activate BP or DMBA. The addition of free CLA or the methyl esters of CLA, linoleic acid, or oleic acid, to control S-9 inhibited the activation of all three mutagens (IQ, BP, and DMBA).

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.194-199
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• 2002

Many oxidative metabolites of tetrahydrocannabinols (THCs), active components of marijuana, were pharmacologically active, and 11-hydroxy-THCs, 11-oxo-${\Delta}^8$-THC, 7-oxo-${\Delta}^8$-THC, 8$\beta$, 9$\beta$-epoxyhexahydrocannabinol (EHHC), 9$\alpha$, l0$\alpha$-EHHC and 3'-hydroxy-${\Delta}^9$-THC were more active than THC in pharmacological effects such as catalepsy, hypothermia and barbiturate synergism in mice. Cannabidiol (CBD), another major component, was biotransfomred to two novel metabolites, 6-hydroxymethyl-${\Delta}^9$-THC and 3-pentyl-6, 7, 7a, 8, 9, lla-hexahydro-I, 7-dihydroxy-7, 1O-dimethyldibenzo[b, d]oxepin (PHDO) through 8R, 9-epoxy-CBD and 85, 9-epoxy-CBD, respectively. Both metabolites exhibited some pharmacological effects comparable to d9 - THe. Cannabinol (CBN), the other major component, was mainly metabolized to ll-hydroxy-CBN by hepatic microsomes of animals including humans. The pharmacological effects of the metabolite were higher than those of CBN demonstrating that II-hydroxylation of CBN is metabolic activation pathway of the cannabinoid as is the case in THCs. Tolerance and reciprocal cross-tolerance developed to pharmacological effects d8 - THC and ll-hydroxy-d8-THC , and the magnitude of tolerance development produced by the metabolite was significantly higher than that by d8-THC. The results indicate that ll-hydroxy-d8-THC has an important role not only in the pharmacological effects but also its tolerance development of d8 - THe. THCs and their metabolites competed to the specific binding of CP-55, 940, an agonist of cannabinoid receptor, to synaptic membrane from bovine cerebral cortex. The Ki value of THCs and their metabolites were closely paralleled to their pharmacological effects in mice. A novel cytochrome P450 (cyp2c29) was purified and identified as a major enzyme responsible for the metabolic activation of d8-THC at the II-position in the mouse liver. cDNA of CYP2C29 was cloned from a mouse cDNA library and its sequence was determined. The oxidation mechanism of THC by cyp2c29 was proposed.

• Natural Product Sciences
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• v.27 no.3
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• pp.201-207
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• 2021

We have previously reported that Acer tegmentosum extract, which is traditionally used in Korea to reduce alcohol-related liver injury, suppresses liver inflammation caused by excessive alcohol consumption and might improve metabolism. The active ingredient, 6-O-galloylsalidroside (GAL), was isolated from A. tegmentosum, and we hypothesized that GAL could provide desirable pharmacological benefits by ameliorating physiological conditions caused by alcohol abuse. Therefore, this study focused on whether GAL could ameliorate alcoholic fat accumulation and repair liver injury in mice. During chronic alcohol consumption plus binge feeding in mice, GAL was administered orally once per day for 11 days. Intrahepatic lipid accumulation was measured in vivo using a noninvasive method, ¹H magnetic resonance imaging, and confirmed by staining with hematoxylin and eosin and Oil Red O. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured using a Konelab system, and the triglyceride content was measured in liver homogenates using an enzymatic peroxide assay. The results suggested that GAL alleviated alcohol-induced steatosis,e as indicated by decreased hepatic and serum triglyceride levels in ethanol-fed mice. GAL treatment also correlated with a decrease in the Cd36 mRNA expression, thus potentially inhibiting the development of alcoholic steatosis via the hepatic de novo lipogenesis pathway. Furthermore, treatment with GAL inhibited the expression of cytochrome P450 2E1 and attenuated hepatocellular damage, as reflected by a reduction in ALT and AST levels. These findings suggest that GAL extracted from A. tegmentosum has the potential to serve as a bioactive agent for the treatment of alcoholic fatty liver and liver damage.

• Journal of Microbiology and Biotechnology
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• v.33 no.4
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• pp.463-470
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• 2023

This study confirmed the change in functional composition and alcohol-induced acute liver injury in Aloe arborescens after fermentation. An acute liver injury was induced by administration of ethanol (3 g/kg/day) to C57BL/6J mice for 5 days. A fermented A. arborescens Miller leaf (FAAL) extract was orally administered 30 minutes before ethanol treatment. After fermentation, the emodin content was approximately 13 times higher than that of the raw material. FAAL extract significantly attenuated ethanol-induced aspartate aminotransferase, alanine aminotransferase, and triglyceride increases in serum and liver tissue. Histological analysis revealed that FAAL extract inhibits inflammatory cell infiltration and fat accumulation in liver tissues. The cytochrome P450 2E1, superoxide dismutase, and glutathione (GSH), which involved in alcohol-induced oxidative stress, were effectively regulated by FAAL extract in serum and liver tissues, except for GSH. FAAL also maintained the antioxidant defense system by upregulating heme oxygenase 1 and nuclear factor erythroid 2-related factor 2 protein expression. In addition, FAAL extract inhibited the decrease in alcohol dehydrogenase and aldehyde dehydrogenase activity, which promoted alcohol metabolism and prevented the activation of inflammatory response. Our results suggest that FAAL could be used as a potential therapeutic agent for ethanol-induced acute liver injury.

• Toxicological Research
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• v.6 no.1
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• pp.51-59
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• 1990

Effects of altering hepatic mixed-function oxidase (MFO) enzyme activities on the metabolism and acute toxicity of parathio were investigated in adult female rats. In vitro hepatic metabolism of parathion to paraoxon was increased by phenobarbital pretreatment (50 mg/kg/day, ip, for 4 consecutive days) and SKF 525-A (50 mg/kg, ip, 1 hr prior to sacrifice) decreased paraoxon formation indicating that phenobarbital induces that form(s) of cytochrome P-450 catalyzing conversion of parathion to paraoxon. Degradation of paraoxon to p-nitrophenol was increased by phenobarbital pretreatment, but not affected by SKF 525-A suggesting that MFO activities play only a minor role in the detoxification of the active metabolite of this insecticide. The phenobarbital-induced increase in paraoxon formation was partially antagonized by SKF 525-A. Significant activity for both parathion activation and paraoxon degradation was also observed in the lung preparation, however, this extrahepatic parathion and paraoxon metabolizing activity was not induced by phenobarbital or inhibited by SKF 525-A pretreatment. Phenobarbital pretreatment increased paraoxon level in livers of rats when measured 3 hr following parathion injection (2 mg/kg, ip). SKF 525-A did not alter parathion or paraoxon levels in brain, blood and liver. Phenobarbital pretreatment decreased the toxicity of parathion (4mg/kg, ip) or paraoxon (1.5 mg/kg, ip) as determined by decreases in lethality and inhibition of brain and lung acetylcholinesterases. An additional SKF 525-A treatment failed to decrease the protective effects of phenobarbital against parathion or paraoxon toxicity. These results suggest that some unknown factors other than hepatic MFO induction are involved in the protective action of phenobarbital against parathion and paraoxon toxicity.