• Journal of Ginseng Research
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• v.46 no.3
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• pp.348-356
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• 2022

Background: Gintonin is a ginseng-derived exogenous G-protein-coupled lysophosphatidic acid (LPA) receptor ligand. Gintonin exerts its neuronal and non-neuronal in vitro and in vivo effects through LPA receptor subtypes. However, it is unknown whether gintonin can bind to the plasma membrane of cells and can transactivate the epidermal growth factor (EGF) receptor. In the present study, we examined whether gintonin-biotin conjugates directly bound to LPA receptors and transactivated the EGF receptor. Methods: We designed gintonin-biotin conjugates through gintonin biotinylation and examined whether gintonin-biotin conjugate binding sites co-localized with the LPA receptor subtype binding sites. We further examined whether gintonin-biotin transactivated the EGF receptor via LPA receptor regulation via phosphor-EGF and cell migration assays. Results: Gintonin-biotin conjugates elicit [Ca²⁺]_i transient similar to that observed with unbiotinylated gintonin in cultured PC3 cells, suggesting that biotinylation does not affect physiological activity of gintonin. We proved that gintonin-biotin conjugate binding sites co-localized with the LPA1/6 receptor binding sites. Gintonin-biotin binding to the LPA1 receptor transactivates the epidermal growth factor (EGF) receptor through phosphorylation, while the LPA1/3 receptor antagonist, Ki16425, blocked phosphorylation of the EGF receptor. Additionally, an EGF receptor inhibitor AG1478 blocked gintonin-biotin conjugate-mediated cell migration. Conclusions: We observed the binding between ginseng-derived gintonin and the plasma membrane target proteins corresponding to the LPA1/6 receptor subtypes. Moreover, gintonin transactivated EGF receptors via LPA receptor regulation. Our results suggest that gintonin directly binds to the LPA receptor subtypes and transactivates the EGF receptor. It may explain the molecular basis of ginseng physiology/pharmacology in biological systems.

• Toxicological Research
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• v.18 no.4
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• pp.331-339
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• 2002

Phenoxy compounds, 2,4-Dichlorophenol acetoxy acid (2,4-D) and 2,4-dichlorophenol (DCP), are widely used as a hormonal herbicide and intermediate for pesticide manufacturing, respectively. In order to assess the potential of these compounds as endocrine disruptors, we studied the androgenicity of them wing in vivo and in vitro androgenicity assay system. Administration of 2,4-D (50 mg/kg/day, p.o.) or DCP (100 mg/kg/day, p.o.) to rats caused an increase in the tissue weight of ventral prostate, Cowpers gland and glands penis. These increase of androgen-dependent tissues were additively potentiated when rats were simultaneously treated with low dose of testosterone (1 g/kg, s.c.). 2,4-D increased about 350% of the luciferase activity in the PC cells transiently cotransfected phAR and pMMTV-Luc at concentration of $10^{-9}$ M. In 2,4-D or DCP-treated castrated rats, testosterone 6$\beta$-hydroxylase activity was not significantly modulated even when rats were co-treated with testosterone. In vitro incubation of 2,4-D and DCP with microsomes at 50 $\mu$M inhibited testosterone 6$\beta$-hydroxylase activity about 27% and 66% in rat liver microsomes, about 44% and 54% in human liver microsomes and about 50% and 45% in recombinant CYP3A4 system, respectively. The amounts of total testosterone metabolites were reduced about 33% and 75% in rat liver microsomes, 69% and 73% in human liver microsomes and 54% and 64% in recombinant CYP3A4 by 2,4-D or DCP, respectively. Therefore, the additive androgenic effect of 2,4-D or DCP by the co-administration of the low dose of testosterone may be due to the increased plasma level of testosterone by inhibiting the cytochrome P450-mediated metabolism of testosterone. These results collectively suggested that 2,4-D and DCP may act as androgenic endocrine disrupter by binding to the androgen receptor as well as by inhibiting the metabolism of testosterone.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.445-450
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• 1996

Gelatinase A is a member of the matrix metalloproteinases that play an important role in cancer invasion and metastasis. In the course of screening gelatinase A inhibitors from microbial sources, a fungal strain PT-262 showed a strong inhibitory activity. The strain was identified as Chaunopycnis alba on the basis of its morphological characteristics. The inhibitor was isolated from acetone extract of mycelial cake by sequential chromatographies on MCI-gel, Sephadex LH-20, and a reverse-phase HPLC column. The purified inhibitor was identified as pyridoxatin by its physico-chemical properties and spectroscopic analysis. Pyridoxatin is not a peptide analog and has cyclic hydroxamic acid moiety. It inhibited activated gelatinase A with an $IC_{50}$ value of 15.2 ${\mu}M$ using fluorescent synthetic peptide. It also had a strong cytotoxicity against human cancer cell lines in vitro. Furthermore, this compound inhibited DNA synthesis with an $IC_{50}$ value of 2.92 ${\mu}M$ in PC-3 prostate cancer cells by [$^3H$]thymidine incorporation assay.

• Fisheries and Aquatic Sciences
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• v.9 no.1
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• pp.14-21
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• 2006

The aim of this study was to investigate in vivo toxicity and effects of two phthalate esters (PEs), di-n-butylphthalate (DBP) and di-2-ethylhexyl phthalate (DEHP), on the immune system of the bagrid catfish, Pseudobagrus fulvidraco. Groups of experimental fish were subjected to daily intraperitoneal injections of 300 or 1000 mg $kg^{-1}$ of DBP or DEHP for 3 days, and the cellularity and functional activity of phagocytes were measured in the spleen and pronephros (head kidney). The number of spleen leukocyte cells increased significantly (p<0.05) in response to low and high doses of DEHP and DBP, respectively; however, the cellularity of the pronephros was more susceptible to higher dose of DEHP than DBP. Nonspecific immunity, as determined by the phagocytic index (PI) and phagocytic capacity (PC), was significantly depressed by DEHP at 1000 $1000mg\;kg^{-1}\;day^{-1}$ in the pronephros at 3 days after injection. Furthermore, significantly (p<0.05) increased levels of serum glutamic oxaloacetate transaminase (GOT) and glutamic pyruvate transaminase (GPT) indicated marked hepatic dysfunction in immunosuppressed fish. Treated fish showed a significant reduction in total serum protein but no significant alteration in lysozyme activity. These results demonstrate the sensitivity of the fish immune response for predicting PE-induced immunotoxicity.

• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.97-104
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• 2000

Screening of Biologically Active Essential Oils from Ligusticum tenuissimum. Kim, Min-Hae, Young-Gil Kim, Jin-Ha Lee, Keo-Pyo Hong, Jung-Ki Hong, Young-Joon Kong, and Hyeon-Yong Lee*. Division of Food and Biotechnology, Kangwon National University, Chunchon 200-701, Korea, 1 Regional Crop Development Station, Kangwon Agricultural Research & Extension Services, Chunchon 200-150, Korea-The biological activities of the crude essential oils from Ligusticum tenuissimum and the control(phthalic anhydride) were compared. About 60% of the growth of MCF7, A549, and Rep3B cells were inhibited by adding 1.0 mg/ml of the crude essential oils and below 40% was observed by the control. Cytotoxicity on human normal lung cell(IMR90) was scored as 34.4% for the crude oil and 26.4% for control, respectively. It was found that the crude essential oils were more effective than the control in anti mutagenecity tested by both Rec-assay and CRG V79 cells. The growth of human T-cell(Jurkat) was enhanced up to 1.21 times by adding the crude essential oil compared with the control. 50% of a-glucosidase activity was inhibited by both the crude essential oil and the control. ACE activities were inhibited 80.1 % and 65.3% by adding 1.0 mg/ml of the crude oil and the control, respectively. The higher enhancement of glutathione-S-transferase activity was observed in the crude oil than those in the control: 301 % v.s 234% at 1.0 mg/ml of the treatment. Thrombolytic activity was measured as 42.9% and 28.6% for the crude oil and the standard, respectively. The effect of the oil on the nerve cells PCI2, was observed as follows: the neurite of PCl2 cells was lengthened up to 255 /-lm longer than 205 /-lm of control. The number of neurite-bearing cells were about two times higher than control. The survival ratio of the crude essential oil was also increased up to 56.4% which was about two fold higher than in control.

• Macromolecular Research
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• v.17 no.12
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• pp.963-968
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• 2009

Liquid crystal (LC; E7 and/or ML-0249)-embedded, poly(vinylidenefluoride-co-hexafluoropropylene) (PVdF-co-HFP)-based, polymer electrolytes were prepared for use in dye-sensitized solar cells (DSSCs). The electrolytes contained 1-methyl-3-propylimidazolium iodide (PMII), tetrabutylammonium iodide (TBAI), and iodine ($I_2$), which participate in the $I_3^-/I^-$ redox couple. The incorporation of photochemically stable PVdF-co-HFP in the DSSCs created a stable polymer electrolyte that resisted leakage and volatilization. DSSCs, with liquid crystal(LC)-embedded PVdF-co-HFP-based polymer electrolytes between the amphiphilic ruthenium dye N719 absorbed to the nanocrystalline $TiO_2$ photoanode and the Pt counter electrode, were fabricated. These DSSCs displayed enhanced redox couple reduction and reduced charge recombination in comparison to that fabricated from the conventional PVdF-co-HFP-based polymer electrolyte. The behavior of the polymer electrolyte was improved by the addition of optimized amounts of plasticizers, such as ethylene carbonate (EC) and propylene carbonate (PC). The significantly increased short-circuit current density ($J_{sc}$, $14.60\;mA/cm^2$) and open-circuit voltage ($V_{oc}$, 0.68 V) of these DSSCs led to a high power conversion efficiency (PCE) of 6.42% and a fill factor of 0.65 under a standard light intensity of $100\;mW/cm^2$ irradiation of AM 1.5 sunlight. A DSSC fabricated by using E7-embedded PVdF-co-HFP-based polymer electrolyte exhibited a maximum incident photon-to-current conversion efficiency (IPCE) of 50%.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.1007-1021
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• 2018

Cancer represents one of the most significant threats to human health on a global scale. Hence, the development of effective cancer prevention strategies, as well as the discovery of novel therapeutic agents against cancer, is urgently required. In light of this challenge, this research aimed to evaluate the effects of several potent bioactive peptides and proteins contained in crocodile white blood cell extract (cWBC) against LU-1, LNCaP, PC-3, MCF-7, and CaCo-2 cancer cell lines. The results demonstrate that 25, 50, 100, and $200{\mu}g/ml$ cWBC exhibits a strong cytotoxic effect against all investigated cell lines ($IC_{50}$ $70.34-101.0{\mu}g/ml$), while showing no signs of cytotoxicity towards noncancerous Vero and HaCaT cells. Specifically, cWBC treatment caused a significant reduction in the cancerous cells' colony forming ability. A remarkable suppression of cancerous cell migration was observed after treatment with cWBC, indicating potent antimetastatic properties. The mechanism involved in the cancer cell cytotoxicity of cWBC may be related to apoptosis induction, as evidenced by typical apoptotic morphology features. Moreover, certain cWBC concentrations induced significant overproduction of ROS and significantly inhibited the $S-G_2/M$ transition in the cancer cell. The molecular mechanisms of cWBC in apoptosis induction were to decrease Bcl-2 and XIAP expression levels and increase the expression levels of caspase-3, caspase-8, and p53. These led to a decrease in the expression level of the cell cycle-associated gene cyclin-B1 and the arrest of cell population growth. Consequently, these findings demonstrate the prospect of the use of cWBC for cancer therapy.

• International Journal of Oncology
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• v.54 no.6
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• pp.2169-2178
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• 2019

Forkhead box A1 (FOXA1) functions as a tumor suppressor gene or an oncogene in various types of cancer; however, the distinct function of FOXA1 in colorectal cancer is unclear. The present study aimed to evaluate whether FOXA1 affects the oncogenic behavior of colorectal cancer cells, and to investigate its prognostic value in colorectal cancer. The impact of FOXA1 on tumor cell behavior was investigated using small interfering RNA and the pcDNA6-myc vector in human colorectal cancer cell lines. To investigate the role of FOXA1 in the progression of human colorectal cancer, an immunohistochemical technique was used to localize FOXA1 protein in paraffin-embedded tissue blocks obtained from 403 patients with colorectal cancer. Tumor cell apoptosis and proliferation were evaluated using a terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and Ki-67 immunohistochemical staining, respectively. FOXA1 knockdown inhibited tumor cell invasion in colorectal cancer cells, and induced apoptosis and cell cycle arrest. FOXA1 knockdown activated cleaved caspase-poly (ADP-ribose) polymerase, upregulated the expression of p53 upregulated modulator of apoptosis, and downregulated BH3 interacting domain death agonist and myeloid cell leukemia-1, leading to the induction of apoptosis. FOXA1 knockdown increased the phosphorylation level of signal transducer and activator of transcription-3. By contrast, these results were reversed following the overexpression of FOXA1. The overexpression of FOXA1 was associated with differentiation, lymphovascular invasion, advanced tumor stage, depth of invasion, lymph node metastasis and poor survival rate. The mean Ki-67 labeling index value of FOXA1-positive tumors was significantly higher than that of FOXA1-negative tumors. However, no significant association was observed between the expression of FOXA1 and the mean apoptotic index value. These results indicate that FOXA1 is associated with tumor progression via the modulation of tumor cell survival in human colorectal cancer.

• Food Science and Preservation
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• v.23 no.7
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• pp.1033-1041
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• 2016

In this study, we evaluated antioxidant and antiproliferating effects of Setaria italica extract (SIE), Panicum miliaceum extract (PME) and Sorghum bicolor extract (SBE). Antioxidant effects of these extracts were determined by assessing DPPH radical scavenging activity, $ABTS^+$ radical scavenging activity, reducing power and superoxide dismutase (SOD)-like activity. From high concentrations ($1,000{\mu}g/mL$) of each extract at DPPH radical scavenging activities of SIE, PME and SBE were 10.5%, 5.5% and 86.8% respectively, $ABTS^+$ radical activities were 4.92%, 5.9% and 62.3% respectively, reducing powers (OD 700) were 0.15, 0.18 and 1.7 respectively, and SOD-like activities were 17.0%, 15.9% and 38.6% respectively. In addition, SBE significantly decreased the cell viability of androgen-sensitive lymph node metastasis type of prostate cancer (LNCaP) cells in a dose-dependent manner. Morphological study of SBE-treated LNCaP cells revealed distorted and shrunken cell masses. SBE-induced cell death was confirmed by observation of nuclear condensation and increased formation of apoptotic bodies. The antiproliferative effect of SBE seems to be associated with the antioxidant activity of its polyphenol content. The results of this study indicate that SBE can exert antioxidant and antiproliferative effects and may be as a useful food material.

• Food Science and Preservation
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• v.15 no.5
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• pp.743-748
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• 2008

Amyloid $\beta$ peptide ($A{\beta}$) is known to increase oxidative stress in nerve cells, leading to apoptosis that is characterized by free radical formation and lipid peroxidation. Neurodegenerative diseases such as Alzheimer's disease (AD) are characterized by large deposits of $A{\beta}$ in the brain. In our study, neuronal protective effects of green tea, along with water activity (0.813), and leaf storage periods (fresh leaf, or leaf stored for up to 4 weeks) were investigated. We measured protective effects against $A{\beta}$-induced cytotoxicity in neuron-like PC12 cells. Powdered green tea was extracted with distilled water at $70^{\circ}C$ for 5 min, and this extract was freeze-dried and stored at $-20^{\circ}C$ until use. In cell viability assays using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), the fresh extract, and that obtained after 1 week of leaf storage, showed the best protective effects against $A{\beta}$-induced neurotoxicity. As oxidative stress causes membrane breakdown, the protective effect of green tea extracts was investigated using lactate dehydrogenase (LDH) and trypan blue exclusion assays. LDH release into the medium was inhibited (by 20-25%) in all tests. In addition, all green tea extracts (fresh, or stored before extraction for up to 4 weeks) showed better cell protective effects ($93.3{\pm}1.8-96.2{\pm}2.4$) than did vitamin C ($91.0{\pm}1.6$), used as a positive control. The results suggest that effectiveness of green tea extracts falls with prolonged leaf storage.