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

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.286-293
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• 2010

Cytokine production is a sensitive indicator for monitoring perturbations of the immune system by xenobiotics in animals and humans. In the present study, we evaluated the changes in $IFN{\gamma}$, IL-5 and $TNF{\alpha}$ mRNA expression after atrazine (ATZ), perfluorooctanoic acid (PFOA) or zearalenone (ZEA) exposure in Jurkat cells. The IC50 (concentration for a 50% inhibition of cell proliferation) of PFOA and ZEA after 3 days culture were $226.6\;{\mu}M$ and $52.6\;{\mu}M$, respectively. The effects of ATZ on cytokine expression followed in increasing order of $IFN{\gamma}$>IL-5>$TNF{\alpha}$ at $3\;{\mu}M$ and at the lower concentrations the degree of effects on three cytokines were less clear between the cytokines when compared to control level. PFOA had marked increasing effect in order of $IFN{\gamma}$>$TNF{\alpha}$>IL-5 mRNA expression at IC50, and these patterns were continued at the lower concentrations, IC50/2 and IC50/4. ZEA caused the overexpression of cytokine mRNAs in order of IL-5>$IFN{\gamma}$>$TNF{\alpha}$ at both IC50 and IC50/2, and at IC50/4 the overexpression order was IL-5>$TNF{\alpha}$. On other hand, $IFN{\gamma}$ was less distinct compared to the control. These data indicate that ATZ, PFOA and ZEA caused the overtranscription of $IFN{\gamma}$, IL-5 and $TNF{\alpha}$ mRNA, and the overproduction of these cytokines may eventually lead to immune disorders.

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.280-285
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• 2010

Glycosaminoglycans (GAGs) and chitosan have been used as matrix materials to support the dermal part of skin equivalent which is used for both pharmacological and toxicological evaluations of drugs potentially used for dermatological diseases. However, their biological roles of GAGs and chitosan in the skin equivalent are still unknown. In the present study, we evaluated whether GAGs and chitosan directly affect keratinocyte stem cells (KSCs) and their transit-amplifying cells (TA cells). Among supporting matrix materials, chitosan significantly increased the number of ${\alpha}6$ $integrin^{high}/CD71^{high}$ human keratinocyte TA cells by 48.5%. In quantitative real-time RT-PCR analysis, chitosan significantly increased CD71 and CD200 gene transcription whereas not ${\alpha}6$ integrin. In addition, the level of the gene transcription of both keratin 1 (K1) and K10 in the chitosan-treated human keratinocytes was significantly lower than those of control, suggesting that chitosan inhibit keratinocyte differentiation. We also found that N-acetyl-D-glucosamine (NAG) and $\beta$-(1-4)-linked D-glucosamine (D-glc), two components of chitosan, have no effect on the expression of CD71, K1, and K10, suggesting that each monomer component of chitosan is not enough to regulate the number of epidermal keratinocyte lineage. Conclusively, chitosan increases keratinocyte TA cell population which may contribute to the cellular mass expansion of the epidermal part of a skin equivalent system.

• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.299-304
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• 2009

Rosiglitazone maleate (RGM) is widely used for improving insulin resistance. RGM is a moderate inhibitor of cytochrome P450 2C8 (CYP2C8) and is also mainly metabolized by CYP2C8. The aim of this study was to determine whether the effect of RGM on CYP2C8 is altered by co-treatment with other drugs, and whether amlodipine camsylate (AC) changes the pharmacokinetics (PK) of RGM. Of the 11 drugs that are likely to be co-administered with RGM in diabetic patients, seven drugs lowered the $IC_{50}$ value of RGM on CYP2C8 by more than 80%. In vitro CYP2C8 inhibitory assays of RGM in combination with drugs of interest showed that the $IC_{50}$ of RGM was decreased by 98.9% by AC. In a pharmacokinetic study, Sprague-Dawley (SD) rats were orally administered 1 mg/kg of RGM following by single or 10-consecutive daily administrations of 1.5 mg/kg/day of AC. No significant changes in the pharmacokinetic parameters of RGM were observed after a single administration of AC, but the AUC and $C_{max}$ values of RGM were significantly reduced by 36% and 31%, respectively, by multiple administrations of AC. In conclusion, RGM was found to be affected by AC by in vitro CYP2C8 inhibition testing, and multiple dosing of AC appreciably changed the pharmacokinetics of RGM. These findings suggest that a drug interaction exists between AC and RGM.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.608-615
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• 2018

Benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea are commonly used preservatives in cosmetics. Recent reports suggested that these compounds may have cellular and systemic toxicity in high concentration. In addition, diazolidinyl urea and imidazolidinyl urea are known formaldehyde (FA) releasers, raising concerns for these cosmetic preservatives. In this study, we investigated the effects of benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea on ROS-dependent apoptosis of rat neural progenitor cells (NPCs) in vitro. Cells were isolated and cultured from embryonic day 14 rat cortices. Cultured cells were treated with 1-1,000 nM benzalkonium chloride, and $1-50{\mu}M$ diazolidinyl urea or imidazolidinyl urea at various time points to measure the reactive oxygen species (ROS). PI staining, MTT assay, and live-cell imaging were used for cell viability measurements. Western blot was carried out for cleaved caspase-3 and cleaved caspase-8 as apoptotic protein markers. In rat NPCs, ROS production and cleaved caspase-8 expression were increased while the cell viability was decreased in high concentrations of these substances. These results suggest that several cosmetic preservatives at high concentrations can induce neural toxicity in rat brains through ROS induction and apoptosis.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.546-552
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• 2018

A comprehensive collection of proteins senses local changes in intracellular $Ca^{2+}$ concentrations ($[Ca^{2+}]_i$) and transduces these signals into responses to agonists. In the present study, we examined the effect of sphingosine-1-phosphate (S1P) on modulation of intracellular $Ca^{2+}$ concentrations in cat esophageal smooth muscle cells. To measure $[Ca^{2+}]_i$ levels in cat esophageal smooth muscle cells, we used a fluorescence microscopy with the Fura-2 loading method. S1P produced a concentration-dependent increase in $[Ca^{2+}]_i$ in the cells. Pretreatment with EGTA, an extracellular $Ca^{2+}$ chelator, decreased the S1P-induced increase in $[Ca^{2+}]_i$, and an L-type $Ca^{2+}$-channel blocker, nimodipine, decreased the effect of S1P. This indicates that $Ca^{2+}$ influx may be required for muscle contraction by S1P. When stimulated with thapsigargin, an intracellular calcium chelator, or 2-Aminoethoxydiphenyl borate (2-APB), an $InsP_3$ receptor blocker, the S1P-evoked increase in $[Ca^{2+}]_i$ was significantly decreased. Treatment with pertussis toxin (PTX), an inhibitor of $G_i$-protein, suppressed the increase in $[Ca^{2+}]_i$ evoked by S1P. These results suggest that the S1P-induced increase in $[Ca^{2+}]_i$ in cat esophageal smooth muscle cells occurs upon the activation of phospholipase C and subsequent release of $Ca^{2+}$ from the $InsP_3$-sensitive $Ca^{2+}$ pool in the sarcoplasmic reticulum. These results suggest that S1P utilized extracellular $Ca^{2+}$ via the L type $Ca^{2+}$ channel, which was dependent on activation of the $S1P_4$ receptor coupled to PTX-sensitive $G_i$ protein, via phospholipase C-mediated $Ca^{2+}$ release from the $InsP_3$-sensitive $Ca^{2+}$ pool in cat esophageal smooth muscle cells.

• Biomolecules & Therapeutics
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• v.28 no.2
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• pp.137-144
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• 2020

Epilepsy is a brain disorder that affects millions of people worldwide and is usually managed using currently available antiepileptic drugs, which result in adverse effects and are ineffective in approximately 20-25% of patients. Thus, there is growing interest in the development of new antiepileptic drugs with fewer side effects. In a previous study, we showed that a Rehmannia glutinosa (RG) water extract has protective effects against electroshock- and pentylenetetrazol (PTZ)-induced seizures, with fewer side effects. In this study, the objective was to identify the RG components that are responsible for its anticonvulsant effects. Initially, a number of RG components (aucubin, acteoside, catalpol, and mannitol) were screened, and the anticonvulsant effects of different doses of catalpol, mannitol, and their combination on electroshock- and chemically (PTZ or strychnine)-induced seizures in mice, were further assessed. Gamma-aminobutyric acid (GABA) receptor binding assay and electroencephalography (EEG) analysis were conducted to identify the potential underlying drug mechanism. Additionally, treated mice were tested using open-field and rotarod tests. Catalpol, mannitol, and their combination increased threshold against electroshock-induced seizures, and decreased the percentage of seizure responses induced by PTZ, a GABA antagonist. GABA receptor binding assay results revealed that catalpol and mannitol are associated with GABA receptor activity, and EEG analysis provided evidence that catalpol and mannitol have anticonvulsant effects against PTZ-induced seizures. In summary, our results indicate that catalpol and mannitol have anticonvulsant properties, and may mediate the protective effects of RG against seizures.

• The Journal of Internal Korean Medicine
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• v.32 no.1
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• pp.33-42
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• 2011

Background : Despite recent advances in cancer management, prognosis of ovarian cancer is poor. Anticancer effects of herbal medicine, such as Euonymus alatus Sieb, Oldenlandia diffusa (Willd.) Roxburgh, and Orostachys japonicus A. Berger, have been reported in treatment of ovarian and cervical cancers, but the systematic approaches to explain their molecular mechanism(s) have not yet been established. Objectives : To establish a basis of understanding for anti-cancer mechanisms of herbal medicine, we profiled protein expression in human ovarian and cervical cancer cells treated with the extracts from Euonymus alatus Sieb, Oldenlandia diffusa (Willd.) Roxburgh and Orostachys japonicus A. Berger. Methods : Human ovarian cancer cell line NIH:OVCAR-3, and human cervical cancer cell line HeLa were employed in the present study. Whole protein was obtained from the cells harvested at 48 hours after the treatment with herbal water-extract, and analyzed by 2DE-based proteomic approach. Results : Various changes of protein expression induced by the herbal treatment were monitored : down-regulation of molecular chaperone (calreticulin variant), glycolytic enzymes (D-3-phosphoglycerate dehydrogenase, glyceraldehyde 3-phosphate dehydrogenase and alpha-enolase), RNA processing molecules (hnRNP A2/B1), and antioxidant protein (peroxiredoxin 1). Conclusions : Repression of glycolysis has been accepted as the mechanism to increase anticancer reagent's effect. Thus, down-regulation of glycolytic enzymes by the herbal extracts suggested a possible synergistic effect of herbs in the presence of platinum-based therapeutics. In further study, as well as the synergistic effect of the herbs, it has to be further validated whether artificial regulation of hnRNP A2/B1 in ovarian cancer cells affects various cancer survival factors, since RNA processing can be interrupted by deranged expression of hnRNP subtypes, and it results in an inhibition of cancer cell growth.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.426-432
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• 2010

The objective of the present study was to evaluate the effect of a mixed extract of three herbs, Panax Notoginseng, Rehmanniae Radix and Acanthopanacis cortex (AIF), for the treatment of horses with experimentally induced osteoarthritis. Twelve healthy male horses were included in this study. Horses were assigned to one of two groups: the AIF group (n=6) or the control group (n=6). Osteoarthritis was induced in all horses by intraarticular injection of sodium monoiodoacetate (0.12 mg/kg). Horses in the AIF group received 3 g of AIF with food daily, and those in the control group received food only. Treatment began on the day of intraarticular injection. Clinical and radiographic evaluations were performed every 2 weeks. At week 12, horses were euthanatized, and postmortem gross pathologic and histologic examinations of the middle carpal joint were performed. There were no significant differences in clinical values between the two groups. Radiographic evaluation revealed that the percentages of narrowness of joint space width in the control group were significantly higher than those in the AIF group (p<0.02). On gross pathologic examination, the mean total dimensions of articular cartilage erosions and fibrillations in the control group ($101.5{\pm}41.5mm^2$) were significantly wider than those in the AIF group ($29.3{\pm}39.7mm^2$; p<0.01). On histopathologic evaluation, significantly higher grades of staining intensity and lower empty lacunae (EL) ratios were found in the AIF group (p<0.03). The present study revealed that AIF had significant disease modifying effects in horses with experimentally induced osteoarthritis.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.469-476
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• 2010

This study was to investigate the effect of apigenin on the bioavailability of paclitaxel after oral and intravenous administration in rats. The effect of apigenin on P-glycoprotein (P-gp), cytochrome P450 (CYP)3A4 activity was evaluated. The pharmacokinetic parameters of paclitaxel were determined in rats after oral (40 mg/kg) or intravenous (5 mg/kg) administration of paclitaxel with apigenin (0.4, 2 and 8 mg/kg) to rats. Apigenin inhibited CYP3A4 activity with 50% inhibition concentration ($IC_{50}$) of 1.8 ${\mu}M$. In addition, apigenin significantly inhibited P-gp activity. Compared to the control group, apigenin significantly increased the area under the plasma concentration-time curve (AUC, p<0.05 by 2 mg/kg, 59.0% higher; p<0.01 by 8 mg/kg, 87% higher) of oral paclitaxel. Apigenin also significantly (p<0.05 by 2 mg/kg, 37.2% higher; p<0.01 by 8 mg/kg, 59.3% higher) increased the peak plasma concentration ($C_{max}$) of oral paclitaxel. Apigenin significantly increased the terminal half-life ($t_{1/2}$, p<0.05 by 8 mg/kg, 34.5%) of oral paclitaxel. Consequently, the absolute bioavailability (A.B.) of paclitaxel was significantly (p<0.05 by 2 mg/kg, p<0.01 by 8 mg/kg) increased by apigenin compared to that in the control group, and the relative bioavailability (R.B.) of oral paclitaxel was increased by 1.14- to 1.87-fold. The pharmacokinetics of intravenous paclitaxel were not affected by the concurrent use of apigenin in contrast to the oral administration of paclitaxel. Accordingly, the enhanced oral bioavailability by apigenin may be mainly due to increased intestinal absorption caused via P-gp inhibition by apigenin rather than to reduced renal and hepatic elimination of paclitaxel. The increase in the oral bioavailability might be mainly attributed to enhanced absorption in the gastrointestinal tract via the inhibition of P-gp and reduced first-pass metabolism of paclitaxel via the inhibition of the CYP3A subfamily in the small intestine and/or in the liver by apigenin. It appears that the development of oral paclitaxel preparations as a combination therapy is possible, which will be more convenient than the i.v. dosage form.