• Korean Journal of Acupuncture
• /
• v.25 no.4
• /
• pp.119-132
• /
• 2008

Objectives : To compare the effects of low-frequency electro-acupuncture (EA) stimulation at left and right GB34s on hepatotoxicity in $CCl_4$-intoxicated rats. Methods : Rats were injected with $CCl_4$ and treated with 2 Hz electro-acupuncture (EA) at left and right GB34s for 15 minutes 3 times per week, for 10 weeks. Holder group, injected with $CCl_4$ and strained in a cylinder for same period as the EA group, was established to compare the hepatotoxicity against the two electroacupuncture groups. To estimate the effects of EA on hepatotoxicity in rats, body weight, liver weight and liver index were measured. Biochemical assays for serum ALT, AST, ALP and total cholesterol ; hematological analysis for RBC, WBC, PLT, hemoglobin, lymphocytes, neutrophils and monocytes ; and histology analysis of liver tissue were also performed. Results : Lymphocyte level in blood was significantly decreased by $CCl_4$-intoxication, and increased by low-frequency electroacupuncture applied on both left and right GB34s. Low-frequency EA applied on right and left GB34s significantly reduced serum ALT and AST, both of which had been increased by $CCl_4$-intoxication. Conclusion : Low-frequency electroacupunctures at both left and right GB34s have hepatoprotective effects on $CCl_4$-induced liver damage in rats. However, no significant differences were found between the effects of EAs at left and right GB34s.

• Molecules and Cells
• /
• v.41 no.5
• /
• pp.401-412
• /
• 2018

Oxymatrine (OMT) often used in treatment for chronic hepatitis B virus infection in clinic. However, OMT-induced liver injury has been reported. In this study, we aim to investigate the possible mechanism of OMT-induced hepatotoxicity in human normal liver cells (L02). Exposed cells to OMT, the cell viability was decreased and apoptosis rate increased, the intracellular markers of oxidative stress were changed. Simultaneously, OMT altered apoptotic related proteins levels, including Bcl-2, Bax and pro-caspase-8/-9/-3. In addition, OMT enhanced the protein levels of endoplasmic reticulum (ER) stress makers (GRP78/Bip, CHOP, and cleaved-Caspase-4) and phosphorylation of c-Jun N-terminal kinase (p-JNK), as well as the mRNA levels of GRP78/Bip, CHOP, caspase-4, and ER stress sensors (IREI, ATF6, and PERK). Pre-treatment with Z-VAD-fmk, JNK inhibitor SP600125 and N-acetyl-l-cysteine (NAC), a ROS scavenger, partly improved the survival rates and restored OMT-induced cellular damage, and reduced caspase-3 cleavage. SP600125 or NAC reduced OMT-induced p-JNK and NAC significantly lowered caspase-4. Furthermore, 4-PBA, the ER stress inhibitor, weakened inhibitory effect of OMT on cells, on the contrary, TM worsen. 4-PBA also reduced the levels of p-JNK and cleaved-caspase-3 proteins. Therefore, OMT-induced injury in L02 cells was related to ROS mediated p-JNK and ER stress induction. Antioxidant, by inhibition of p-JNK or ER stress, may be a feasible method to alleviate OMT-induced liver injury.

• Environmental Analysis Health and Toxicology
• /
• v.23 no.4
• /
• pp.325-335
• /
• 2008

The protective effects of the Naringin, on carbon tetrachloride ($CCl_4$)-induced hepatotoxicity and the possible mechanisms involved in this protection were investigated in mice. Pretreatment with Naringin prior to the administration of $CCl_4$ significantly prevented an increase in serum alanine, aspartate aminotransferase activity and hepatic lipid peroxidation in a dose-dependent manner. In addition, pretreatment with Naringin also significantly prevented the depletion of glutathione (GSH) content in the livers of $CCl_4$-induced mice. However, reduced hepatic glutathione levels was unaffected by treatment with Naringin alone. In addition, Naringin prevented $CCl_4$-induced apoptosis and necrosis, as indicated by a liver DNA laddering. To determine whether caspase-8,-3 pathway involved in $CCl_4$-induced acute liver injury, caspase-8, -3 activities were tested by ELISA. Naringin attenuated $CCl_4$induced caspase-8, -3 activities in mouse livers. $CCl_4$-induced hepatotoxicity was also prevented, as indicated by a liver histopathologic study. The effects of Naringin on the cytochrome P450 (CYP) 2E1, the major isozyme involved in $CCl_4$ were also investigated. Treatment of mice with Naringin resulted in a significant decrease of the CYP2E1-dependent hydroxyl at ion and aniline in a dose-dependent manner. These findings suggest that protective effects of Naringin against the $CCl_4$-induced hepatotoxicity may be due to its ability to block CYP2E1-mediated $CCl_4$ bioactivation and that is also protects against caspase-8, -3 pathway mediated apoptosis.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.28 no.1
• /
• pp.80-90
• /
• 2018

Objectives: This study was performed to propose a domestic occupational exposure limit(OEL) following a health hazard assessment, calculation of a non-carcinogenicity reference concentration worker($RfC_{worker}$) value, and examination of international agencies' exposure limits. It also recommends legal management within the Occupational Safety and Health Act for HCFC-123, which caused an acute hepatotoxicity incident. Methods: An acute hepatotoxicity incident due to the fire extinguishing agent HCFC-123 was investigated. Toxicological hazard and health hazard classifications were examined and a non-carcinogenicity $RfC_{worker}$ value was calculated for HCFC-123. An OEL and the necessity of legal management were recommended as well. Results and Conclusions: An OEL for HCFC-123 of 10 ppm($62.5mg/m^3$), which considered the $RfC_{worker}$ value, 5.56 ppm, produced in dose-response assessment and the exposure level of 19.1-20.9 ppm measured as an eight-hour TWA(time-weighted average) in the incident place, is recommended. HCFC-123 is urged to be included as a chemical requiring legal management in the Occupational Safety and Health Regulations. In addition, it is recommended that a peak exposure of ACGIH be adopted in the Notice of the Ministry of Employment and Labor.

• Toxicological Research
• /
• v.35 no.4
• /
• pp.295-301
• /
• 2019

In this review, we describe the absorption rates (Caco-2 cell permeability) and hepatic/plasma pharmacokinetics of 53 diverse chemicals estimated by modeling virtual oral administration in rats. To ensure that a broad range of chemical structures is present among the selected substances, the properties described by 196 chemical descriptors in a chemoinformatics tool were calculated for 50,000 randomly selected molecules in the original chemical space. To allow visualization, the resulting chemical space was projected onto a two-dimensional plane using generative topographic mapping. The calculated absorbance rates of the chemicals based on cell permeability studies were found to be inversely correlated to the no-observed-effect levels for hepatoxicity after oral administration, as obtained from the Hazard Evaluation Support System Integrated Platform in Japan (r = -0.88, p < 0.01, n = 27). The maximum plasma concentrations and the areas under the concentration-time curves (AUC) of a varied selection of chemicals were estimated using two different methods: simple one-compartment models (i.e., high-throughput toxicokinetic models) and simplified physiologically based pharmacokinetic (PBPK) modeling consisting of chemical receptor (gut), metabolizing (liver), and central (main) compartments. The results obtained from the two methods were consistent. Although the maximum concentrations and AUC values of the 53 chemicals roughly correlated in the liver and plasma, inconsistencies were apparent between empirically measured concentrations and the PBPK-modeled levels. The lowest-observed-effect levels and the virtual hepatic AUC values obtained using PBPK models were inversely correlated (r = -0.78, p < 0.05, n = 7). The present simplified PBPK models could estimate the relationships between hepatic/plasma concentrations and oral doses of general chemicals using both forward and reverse dosimetry. These methods are therefore valuable for estimating hepatotoxicity.

• Korean Journal of Food Science and Technology
• /
• v.53 no.3
• /
• pp.344-347
• /
• 2021

In this study, the hepatotoxic mechanism of chaparral (Larrea tridentata) was investigated through in vitro experiments that measured cell death, inflammatory cytokine secretion, and intracellular fat accumulation by treating HepG2 hepatocytes with a 70% ethanol extract of chaparral at concentrations ranging from 0.001 to 100 ㎍/mL. Cell death was observed after treatment with chaparral extract at concentrations of 1-100 ㎍/mL (p<0.05). The secretion of the inflammatory cytokines, interleukin-8 and macrophage-colony stimulating factor, and fat accumulation were significantly increased even at a concentration of 0.1 ㎍/mL, which was 10 times lower than the observed concentration resulting in cell death (p<0.05). Hepatitis caused by inflammatory cytokine secretion and fat accumulation was shown to be a form of hepatotoxicity induced by chaparral extract. Hepatitis was expressed at a concentration lower than that causing serious toxicity such as cell death, suggesting that hepatotoxicity, including hepatitis, may be caused by ingestion of low concentrations of chaparral.

• Journal of Life Science
• /
• v.20 no.1
• /
• pp.133-141
• /
• 2010

The protective effect of a mixed powder from solid-cultured and liquid-cultured Lentinus edodes mycelia (2:1, w/w) (designate LED) on the carbon tetrachloride ($CCl_4$)- and ethanol-induced hepatotoxicity of male Sprague-Dawley (SD) rat was investigated. In the $CCl_4$-induced rat hepatotoxicity experiment, rats of 4 groups (6 rats/group) were administere with Normal (0.2 ml distilled water), Control (0.2 ml distilled water), LED (LED 200 mg/kg BW + 0.2 ml distilled water), and Silymarin (200 mg/kg BW + 0.2 ml distilled water), p.o., daily for 2 weeks. Afterwards, all groups except for the Normal group were subjected to abdominal injection with $CCl_4$ ($CCl_4$ : corn oil, 1:1 v/v; 0.5 ml/kg BW). For the ethanol- induced rat hepatotoxicity experiment, rats were divided into 5 groups (5 rats/group): Normal; Pair-fed control (PFC); Control (ethanol); LED (ethanol + LED 200 mg/kg BW); and Silymarin (ethanol + silymarin 200 mg/kg BW). Rats of the Normal and PFC groups were fed a basal liquid diet, and rats of the Control, LED, and Silymarin groups were fed a liquid ethanol diet containing LED or Silymarin. Eight weeks later, blood and liver samples were collected to analyze biomarkers. In $CCl_4$-induced SD rats, LED elevated hepatic superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH peroxidase) activities and thiobarbituric reactive substances (TBARS) were reduced, resulting in the reduction of glutamate-oxalate transaminase (GOT), glutamate-pyruvate transaminase (GPT) and lactic dehydrogenase (LDH) activities in plasma. Similar results of these enzymes and biochemical markers in both liver tissues and plasma were seen in ethanol-induced hepatotoxicity of SD rats. In addition, elevated alcohol dehydrogenase (ADH) activity and reduced expression of cytochrome p450 mixed monooxygenase enzyme (CYP2E1) were seen in liver tissues from ethanol-treated rats by LED treatment. These effects of LED were similar to those of Silymarin. In in vitro experiments, LED showed antioxidant activity in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) system and mouse liver mitochondria system induced by NADPH/$Fe^{2+}$ and cumine hydroperoxide (CuOOH). These results indicate that LED protected SD rat hepatotoxicity, induced by $CCl_4$ and ethanol, through its antioxidative activity and might be useful as a material for protection from hepatoxicity in humans.

• Toxicological Research
• /
• v.14 no.3
• /
• pp.293-300
• /
• 1998

Previous studies have shown that the heterocycles including thiazoles are efficacious in inducing phase phase II metabolizing enzyme as well as certain cytochrome P450s and that the inductin of these matabolizing enzymes by the heterocyclic agents is highly associated with their hepatotoxicity. In the present study, the effects of benzylisothiazole (BIT), which has a isothiazole moiety, on the expression of microsomal epoxide hydrolase (mEH), major glutathione S-transerases and cytochrome P450s were studied in the rat liver in association with its hepatotoxicity. Treatment of rats with BIT(1.17 mmol/kg, 1~3d) resulted in substantial increases in the mEH. rGSTA2, rGSTA2, rGSTM1 and rGSTM2 mRNA levels, whereas rGSTA3 and rGSTA5 mRNA levels were increased to much lesser extents. A time-course study showed that the mRNA levels of mEH and rGSTs were greater at 24hr after treatment than those after 3 days of consecutive treatment. Relative changes in mEH and rGST mRNA levels were consistent with those in the proteins, as assessed by Western immunoblot analysis. Hepatic cytochrom P450 levels were monitored after BIT treatment under the assumption that metabolic activation of BIT may affect expression of the enzymes in conjunction with hepatotoxicity. Immunoblot analysis revealed that cytochrome P450 2B1/2 were 3-to 4-fold induced in rats teatd with BIT(1.17 mmol/kg/day.3days), whereas P450 1A2, 2C11 and 3A1/2 levels were decreased to 20~30% of those in unteatd rats. P450 2E1 was only slightly decreased by BIT. Thus, the levels of several cytochrome P450s were suppressed by BIT treatment. Rats treated with BIT at the dose of 1.17mmol/kg for 3 days exhibited extensive multifocal nodular necrosis with moderate to extensive diffuse liver cell degeneration. No notable toxicity was observed in the kidney. These results showed that BIT induces mEH and rGSTs in the liver with increases in the mRNA levels, whereas the agent significantly decreased major cytochrome P450s. The changes in the detoxifying enzymes might be associated with the necrotic liver after consecutive treatment.

• Biomolecules & Therapeutics
• /
• v.16 no.3
• /
• pp.197-202
• /
• 2008

In our previous publication we compared the gene expression profiles on hepatotoxicants exposure to assess the comparability between in vivo and in vitro test systems. We investigated global gene expression from both mouse liver and mouse hepatic cell line treated with thioacetamide (TAA) and identified several common genes. In this study, we selected genes to validate them as potential biomarkers for hepatotoxicity on the relevance of in vitro and in vivo system. Three up-regulated, aquaporin 8 (Aqp8), glutathione peroxidase 1 (Gpx1), succinate-CoA ligase, GDP-forming, alpha subunit (Suclg1) and two down-regulated, DnaJ (Hsp40) homolog subfamily C member 5 (Dnajc5) and tumor protein D52 (Tpd52) genes were tested for their effects in vitro. For characterization of gene function, short interfering RNA (siRNA) for each gene was synthesized and transfected in mouse hepatic cell line, BNL CL.2. Cell viability, mRNA expression level and morphological alterations were investigated. We confirmed siRNA transfection against selected five genes induced down-regulation of respective mRNA expression. siRNA transfection in general decreased cell viability in different degrees and induced morphological changes such as membrane thickening and alterations of intracellular structures. This suggests that these genes could be associated with TAA-induced toxicity. Furthermore, these genes may be used in the investigation of hepatotoxicity for better understanding of its mechanism.

• Journal of Food Hygiene and Safety
• /
• v.15 no.3
• /
• pp.226-234
• /
• 2000

Protective effect of Corydalis ternata against the carbon tetrachloride-induced toxicity was investigated. Carbon tetrachloride($CCl_4$) induces hepatotoxicity due to the reactive free radical(CCl$_3$ . ) generated by cytochrome P-450 enzyme. We examined effects of hexane, chloroform, butanol and water fractions prepared from the Corydalis ternata methanol extract. Rats were treated with those for 3 days, and liver microsomes and cytosols were prepared at 24 hour after last treatment. Hepatoprotective activity of the water fraction was higher than that of other fractions. To examine mechanism of the hepatoprotective effect of Corydalis ternuta, we measured contents of malondialdehyde(MDA), cytochrome P46O(CYP), glutathione, calcium as well as the activities of NADPH-CYP reductase, glutathione S-transferase(GST), superoxide dismutase(SOD), glutathione peroxidase(GPX) and catalase. The fraction inhibited production of MDA, content of CYP and calcium in liver of water fractions - treated rats as compared with those of CCl4-treated rats. The GST activity was increased. We speculate that the O2 radical scavenging activities of the water fraction might play a key role in the mechanism opposing the progression of $CCl_4$-induced hepatotoxicity, but the activities of SOD, GPX, CAT were decreased. These results suggest that the mechanism might be mainly due to the decrease of CYP contents, act as calcium channel blocker and increase of GST activity rather than $O_2$ radical scavenging activities.