• Journal of Life Science
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• v.26 no.2
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• pp.226-233
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• 2016

Vascular smooth muscle cell (VSMC) apoptosis has been identified in various vascular diseases, including atherosclerosis and restenosis after angioplasty, and has been known to precipitate atherosclerotic plaque instability and rupture. Oxysterols are known as inducers of apoptosis in VSMC, and 7-ketocholesterol (7KC) is the major nonenzymically formed oxysterol in atherosclerotic lesions. The precise mechanism underlying VSMC apoptosis is still poorly understood. In this study, we investigated whether 7KC causes apoptosis, and characterized its apoptotic mechanisms in primary cultured rat aortic VSMC. Cell viability was assessed by MTT assay and trypan blue assay. Apoptosis was assessed by flow cytometry, immunofluorescence, immunoprecipitation, and Western blot analyses. 7KC markedly decreased the VSMC viability in a time- and concentration-dependent manner, and increased the production of 4-hydroxynonenal (HNE), a major end-product of lipid peroxidation, which also decreased the VSMC viability. Pretreatment with 2,4-dinitrophenylhydrazine, a well-known reagent of lipid peroxidation-derived aldehydes, significantly restored the 7KC-decreased viability of VSMC. Furthermore, HNE, as well as 7KC, reduced the level of total Akt, a major mediator of cell survival. The 7KC-decreased level of total Akt was significantly restored by pretreatments with 2,4-dinitrophenylhydrazine and N-acetylcysteine. Lactacystin, a proteasome inhibitor, protected VSMC against apoptosis and Akt degradation, but did not inhibit HNE production. In the immunoprecipitation assay, 7KC increased HNE-modified Akt. From the results, it seems that, in atherosclerotic lesions, 7KC induces HNE production in VSMC, and this HNE binds to Akt, proceeding to proteasomal degradation of Akt, through which mechanism the atherosclerotic plaque instability may be facilitated.

• The Korean Journal of Pesticide Science
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• v.6 no.2
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• pp.96-104
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• 2002

This study was carried out to investigate cytotoxicity of paraquat on NIH 3T3 fibroblasts, toxicity of paraquat and compensatory effects of 3-methylcholanthrene (3-MC) on the rat lung. In order to conduct MIT [3-(4,5-Dimethylthiazol-2-yl) -2,5-diphenyl -2H-tetrazolium-bromide] and NR (Neutral red) assay, the $5.0{\times}10^4cell/ml$ of NIH 3T3 fibroblast in each well of 24 multi-dish were cultured. After 24 hours, the cells were treated with solution of paraquat (1, 25, 50 and $100{\mu}M$ respectively). After the NIH 3T3 fibroblast of all groups were cultured in same condition for 48 hours. MIT and NR assay were performed to evaluate the cytotoxicity of cell organelles. $MTT_{50}\;and\;NR_{50}$ of paraquat were $1668.97{\mu}M\;and\;1030.85{\mu}M$, respectively. These $IC_{50}$ of Paraquat were decided as a low cytotoxicity by Borenfreund and Puemer (1984). In order to observe the toxicity and compensatory effects of paraquat on the rat lung, Spraque Dawley male rats were used as experimental animals and were divided into paraquat only treated group and simultaneous application group of paraquat and 3-MC, at 30 min and 1, 3, 6, 12, 24, 48 and 96 hrs interval after each treatment. The animals were sacrificed by decapitation and their or the lungs were immediately removed, immersed in fixatives, and were processed with routine method for light microscopic study. Paraffin sections were stained with H&E and iron hematoxylin of Verhoeff. Under the light microscopy, erythrocytes were full in alveolar capillaries at 3 hrs and congested at 24 hrs after paraquat administration. The great alveolar cells (Type II cell) were increased and mitosis of great alveolar were observed in interalveolar septa. Many lymphocytes, macrophages and polymorphonuclear (PMN) cells were observed in connective tissue surrounding lung tissue and germinal center in lymph follicles of terminal bronchiole. Alveolar macrophages were increased in interalveolar septa and alveoli at 48 hrs. And observed many alveolar macrophages at 96 hrs. In iron hematoxylin stain of Verhoeff, Collagen fiber were increased in respiratory bronchiole, interalveolar septa and alveoli and breath of alveoli, and alveolar pore were broaden. But, in paraquat plus 3-MC treated group, morphological changes were mild in lung tissue. These results indicate that 3-MC has a compensatory effects against toxicity of paraquat by conjugation with oxygen.

• Tuberculosis and Respiratory Diseases
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• v.53 no.3
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• pp.275-284
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• 2002

Background : Gemcitabine is a new anti-cancer agent for treating non-small cell lung cancer. Functioning as an antimetabolite, it induces anti-cancer effects by suppressing DNA synthesis after being incorporated into the DNA as a cytosine arabinoside analogue. When Gemcitabine is incorporated into the DNA, the p53 gene may be activated by induction of the DNA defect. However, there are a few studies on the molecular mechanisms of Gemcitabine-induced cell death. This study examined the role of p53 in Gemcitabine-induced cell death. Methods : A549 and NCl-H358 lung cancer cells were used in this study. The cell viability test was done using a MTT assay at Gemcitabine concentrations of 10nM, 100nM, 1uM, 10uM and 100uM. A FACScan analysis with propium iodide staining was used for the cell cycle analysis. Western blot analysis was done to investigate the extent of p53 activation. For the functional knock-out of p53, stable A549-E6 cells and H358-E6 cells were transfected pLXSN-16E6SD which is over expresses the human papilloma virus E6 protein that constantly degrades p53 protein. The functional knock out of p53 was confirmed by Western blot analysis after treatment with a DNA damaging agent, doxorubicine. Results : Gemcitabine exhibited cell toxicity in dose-dependent fashion. The cell cycle analysis resulted in an S phase arrest. Western blot analysis significant p53 activation in time-dependent manner. Gemcitabine-induced cytotoxicity was reduced by 20-30% in the A549-E6 cells and the 30-40% in H358-E6 cells when compared with the A549-neo and H358-neo control cells. Conclusion : Gemcitabine induces an S phase arrest, as expected for the anti-metabolite, and activates the p53 gene, Furthermore, p53 might play an important role in Gemcitabine-induced cell death. Further investigation into the molecular mechanisms on how Gemcitabine activates the p53 gene and its signaling pathway are recommended.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.232-239
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• 2012

A laboratory experiment was conducted to determine the content of phenolics and flavonoids, antioxidant activity and cytotoxicity from methanol extracts of different plant parts of $T.$ $officinale$ F. H. Wigg. Total phenolics [mg chlorogenic acid equivalents (FAE) $kg^{-1}$ DW] was highest in flower extracts (72.0 mg $kg^{-1}$), followed by leaf, root, and stalk extracts of $T.$ $officinale$ ($p$ < 0.05). The result of total flavonoid level [mg naringin equivalents $kg^{-1}$ DW] had same tendency to differential total phenolics contents among plant parts, but showed lower ranges of amount. The antioxidant activity of the methanol extracts from all the plant parts dose-dependently increased. DPPH (1,1-diphenyl-2-picryl hydrazyl radical) free radical scavenging activity was highest in flower extracts ($IC_{50}$ value = 624.3 mg $kg^{-1}$ ), and followed by leaf, root, and stalk extracts of $T.$ $officinale$ ($p$ < 0.05). By means of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, cell viability of Calu-6 for human pulmonary carcinoma and SNU-601 for human gastric carcinoma showed the lowest $IC_{50}$ value in the flower extracts ($IC_{50}$ value = 85.7 and 311.4 mg $kg^{-1}$, respectively), indicating the highest cytotoxicity. The results suggested that total phenolics content and total flavonoids level in different plant parts of $T.$ $officinale$ were highly correlated with antioxidative ($r^2$=0.7280 to 0.9971) or with cytotoxic activities ($r^2$=0.5795 to 0.9515).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.51-59
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• 2012

Contents of phenolics and flavonoids, antioxidant activity and cytotoxicity were investigated in the methanol extracts of three different $Taraxacum$ species, $Taraxacum$ $coreanum$, $Taraxacum$ $mongolicum$, and $Taraxacum$ $officinale$. Total phenolics content at $1000mg\;kg^{-1}$ was more present in shoot parts than in roots, and was highest in $T.$ $mongolicum$ shoot and root extracts (76.8 and $40.0mg\;kg^{-1}$, respectively), followed by $T.$ $coreanum$ and $T.$ $officinale$ ($p$ < 0.05). Total flavonoid level had same tendency to total phenolics among $Taraxacum$ species, showing lower amounts ($6.5{\sim}36.4mg\;kg^{-1}$) than total phenolics. The antioxidant activity of the methanol extracts from all the species dose-dependently increased. DPPH free radical scavenging activity at $1,000mg\;kg^{-1}$ was highest in shoot and root extracts from $T.$ $mongolicum$ by 89.6 and 83.4%, respectively. According to MTT assay, cell viability of Calu-6 (human pulmonary carcinoma) was lowest in the $T.$ $mongolicum$ shoot and root extracts ($IC_{50}$ values=83.4 and $66.4mg\;kg^{-1}$, respectively), and followed by $T.$ $coreanum$ and $T.$ $officinale$ (lowest). Calu-6 was more sensitive to the extracts than SNU-601 (human gastric carcinoma). Antioxidative and anticancer activities in three different $Taraxacum$ species was more correlated with total phenolics content ($r^2$=0.0097 to 0.6213) than with total flavonoids level ($r^2$=0.0027 to 0.4627). The results showed total phenolics content and total flavonoids level were highly correlated with anticancer activity and antioxidant activity, and their content and activities were different depending on species.

• Food Engineering Progress
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• v.22 no.4
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• pp.315-320
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• 2018

This study examined the effects of drying methods of Aronia melanocarpa on contents of total polyphenols and flavonoids, antioxidant activity and anti-inflammatory activity. As a result, freeze-dried aronia extract (FDAE) significantly exhibited higher contents of total polyphenols and flavonoids (155.76 mg GAE/g and 105.70 mg QE/g) than hot-air dried aronia extract (HDAE) (134.93 mg GAE/g and 82.29 mg QE/g). Also, FDAE showed greater antioxidant activity than HDAE in both DPPH and ABTS. For anti-inflammatory activity, NO production from lipopolysaccharide activated RAW264.7 cell reduced at a dose-dependent manner in both FDAE and HDAE. However, reduction rate of NO production is higher in FDAE (62.7%) than in HDAE (33.5%). These results suggest that comparatively, freeze-drying is a better method for preserving the antioxidant and anti-inflammatory activities and of aronia.

• Korean Journal of Microbiology
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• v.48 no.1
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• pp.52-56
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• 2012

The aim of this study was to evaluate the antimicrobial effect of carvacrol against periodontopathic and cariogenic bacteria and its cytotoxicity in human oral tissue cells. We tested their antibacterial properties against mutans streptococci and five major periodontopathic bacterial species involved in periodontal disease. The antimicrobial activity was evaluated by the minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The cell viability of carvacrol on normal human gingival fibroblast (NHGF) cells was tested by metyl thiazolyl tetrazolium assay. The data showed that carvacrol had remarkable antimicrobial effect on tested bacteria with a MIC and MBC values ranged from 16 to $128{\mu}g/ml$ and from 32 to $128{\mu}g/ml$, respectively. In cell toxicity studies, carvacrol had significantly decreased cell viability when NHGF cells were treated at $128{\mu}g/ml$. These findings suggest that carvacrol has a strong antimicrobial activity against periodontopathic and cariogenic bacteria. However, in order to use it as a component of gargling solution or toothpaste, its concentration should be below $64{\mu}g/ml$ and other compounds having an antimicrobial activity against periodontopathic and cariogenic bacteria should be used together.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.92-98
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• 2012

The co-precipitation technique has been applied to synthesize biphasic calcium phosphate (BCP). $Ca(NO_3)_2{\cdot}4H_2O$, $(NH_4)_2HPO_4$, TEOS and $Mg(NO_3)_2{\cdot}6H_2O$ as the starting materials was used. After the heat treatment of powder crystalline phases HAp and ${\beta}$-TCP analysis showed a mixed phase. The overall spectra appear to have mainly two modes corresponding to characteristic $PO^{3-}_4$ and $OH^-$ groups. After immersion in Hanks' Balanced Salt Solution (HBSS) for 1 week a precipitation started to be formed with individual small granules on the specimen surface. An MTT assay indicated that ionic substituted BCP powders had no cytotoxic effects on MG-63 cells, and that they have good biocompatibility.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.215-225
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• 2005

Objective : It has long been known about the osteogenic effect of CTF-HAS on bone tissues. However, it has not been determined the effect of CTF-HAS on cancer cells. The purpose of this study is to screen the CTF-HAS mediated differentially expressed genes in cancer cells such as HepG2 hepatoma cells lines. Oligonucleotide microarray approach were employed to screen the differential expression genes. Methods : CTF-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. Cells were treated with various concentrations of CTF-HAS(0.1, 0.5, 1.5, 10, $20mg/m{\ell}$) for 24 h. Cytotoxicity was tested by MTT assay. To screen the differentially expressed genes in cancer cells, cells were treated with $1.5mg/m{\ell}$ of CTF-HAS. For oligonucleotide microarray assay, total RNA was used for gene expression analysis using oligonucleotide genechip (Human genome U133 Plus 2.0., Affimatrix Co.). ResuIts : It has no cytotoxic effects on HepG2 cells in all concentrations (0.1, 0.5, 1.5, 10, $20mg/m{\ell}$). More than twofold up-regulated genes were 19 genes. The number of more than twofold down-regulated genes was 13. Discussion : This study showed the screening of CTF-HAS mediated differentially regulated genes using combined approaches of oligonucleotide microarray. The screened genes will be used for the better understanding in therapeutic effect of CTF-HAS on cancer field.

• Journal of Life Science
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• v.30 no.5
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• pp.460-467
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• 2020

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers in the word. Although radiation and chemotherapy are generally effective, there are various side effects that greatly limit the effectiveness of these treatments. Therefore, traditional herbs may have potential as important resources for the discovery of liver cancer therapeutics. In this study, we selected three Korean herbal medicine formulas from the Donguibogam, namely Bigihwan (BGH), Daechilgithang (DCGT), and Mokwhyangbinranghwan (MHBRH), and evaluated their anti-cancer effects on HCC cells. According to our results of three ethanol extracts, BGH was more effective at suppressing HCC growth than DCGT or MHBRH. Furthermore, flow cytometry analysis showed that inhibition of HCC proliferation by the three extracts was associated with the induction of apoptosis and autophagy. In particular, BGH significantly increased mitochondrial impairment and showed the possibility of inducing mitophagy in comparison with the other two extracts. BGH prominently upregulated the levels of microtubule-associated protein light chain-3 which was accompanied by a decrease in the expression of anti-apoptotic Bcl-2 without altering the expression of pro-apoptotic Bax. In addition, the levels of PTEN-induced kinase 1 were also markedly increased in BGH-treated HCC cells. Moreover, autophagy blocking improved cell viability and reduced apoptosis after the three treatments, indicating that autophagy by these extracts enhances HCC cells against cytotoxicity. In conclusion, our findings show that BGH demonstrates the highest anti-cancer activity among the three formulas and inhibits the proliferation of HCC cells through autophagy induction.