• YAKHAK HOEJI
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• v.46 no.1
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• pp.18-23
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• 2002

Ailanthus altissima has been used to settle an upset stomach, to alleviate a fever and as an insecticide. We reported that the water extract of A. altissima induced apoptotic cell death in Jurkat T-acute Iymphoblastic leukemia cells. Here, we showed the dose-dependent inhibitions of cell viability by the extract, as measured by cell morphology. The cell cycle control genes are considered to play important roles in tumorigenesis. The purpose of the present study is also to investigate the effect of A. altissima on cell cycle progression and its molecular mechanism in the cells. The level of p21 protein was increased after treatment of the extract, whereas both Bcl-2 and Bax protein levels were not changed. These results suggest that A. altissima induces apoptotic cell death via p21-dependent signaling pathway in Jurkat cells which delete wild type p53. Gl checkpoint related gene products tested (cyclin D3, cyclin dependent kinase 4, retinoblastoma, E2Fl) were decreased in their protein levels in a dose-dependent manner after treatment of the extract Taken together, these results indicate that the increase of apoptotic cell death by A. altissima may be due to the inhibition of cell cycle in Jurkat cells.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.43-46
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• 2009

The immunosuppressive properties of flavonoids were examined for the first time by testing their effects on T-cell-mediated antibody production, using a classical plague-forming cell (PFC) assay in mice. Among the tested flavonoids including naringenin, chrysin, flavonol, galangin, quercetin, morin, myricetin and biochanin A, only quercetin, orally administered at 25 mg/kg, significantly inhibited the number of IgMproducing PFCs induced by sheep red blood cells (SRBC). Interestingly, biochanin A (isoflavone) increased the number of PFCs, suggesting an immunostimulatory effect. The other flavonoids tested did not inhibit or enhance PFC response significantly. Quercetin was also found to show thymus atrophy dose-dependently at 5-500 mg/kg. All these results indicate that quercetin inhibits in vivo antibody production probably by inhibiting T-cell function.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1314-1319
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• 2009

In previous study, we have shown that continentalic acid (CA) isolated from Aralia continentalis induced the growth inhibition and apoptosis in HepG2 cells. In this study, we examine the effects of CA from A. continentalis on growth inhibition and apoptosis induction in human leukemia HL-60 and mouse fibroblast NIH 3T3 cell lines. The results demonstrated that CA decreased cell growth of leukemia HL-60 cells but not human HaCaT keratinocytes, assessed with the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] and LDH (lactate dehydrogenase) assay. Flow cytometric analysis of mouse fibroblast cell lines exposed to CA showed that apoptotic cells increased in a time- and dose-dependent manner. Treatment with CA decreased the number of normal cells and increased the number of early apoptotic and late apoptotic cells in a dose-dependent manner. The induction of apoptosis in mouse cell lines by CA was mediated through the activation of caspase-3, Bak, and Bax and the down-regulation of Bcl-2. Our results suggest that CA efficiently induces apoptosis in human leukemia cells.

• Journal of Nutrition and Health
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• v.34 no.8
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• pp.896-904
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• 2001

Conjugated linoleic acid(CLA) is a group of positional and geometric isomers of linoleic acid(LA) and exhibits anticarcinogenic activity in multiple experimental animal models. Cis-9,trns-11(c9t11) and trans-10,cis-12(t10c12) CLA are the principal isomers found in foods. The present study was performed to determine whether CLA and the two isomers inhibits HT-29 cell proliferation and to assess whether such an effect was related to changes in secretion of eicosanoids. Cells were incubated in serum-free medium with various concentrations(0 to 20$\mu$M) of CLA or LA. CLA inhibited cell proliferation in a dose-dependent manner, with maximal inhibition(70 $\pm$ 1%) observed at 20$\mu$M concentration after 96 hours. However, LA had no effect at the same concentration range. To compare the ability of c9f11 and t10c12 to inhibit cell proliferation, cells were incubated with increasing concentrations(0 to 4$\mu$M) of these isomers. T10c12 inhibited cell proliferation in a dose-dependent manner. A 66 $\pm$ 2% decrease in cell number was observed within 96 hours after addition of 4$\mu$M t10c12. By contrast, c9t11 had no effect. The concentrations of CLA and the two isomers in the plasma membrane were increased when they were added to the incubation medium. However, they did not alter the levels of arachidonic acid in plasma membrane. To assess whether the proliferation inhibiting effect of CLA was related to changes in eicosanoid production, prostaglandin E$_2$(PGE$_2$) and leukotriene B$_4$(LTB$_4$) concentrations in conditioned media were estimated by a competitive enzyme immunoassay. Both CLA and t10c12 increased the production of materials reactive to PGE$_2$ and LTB$_4$ antibodies in a dose-dependent manner. By contrast, c9t11 had no effect. These results indicate that inhibition of HT-29 cell proliferation by CLA is attributed to the effect of the t10v12 isomer. The materials reactive to PGE$_2$ and LTB$_4$ antibodies may inhibit growth stimulatory effect of arachidonic acid-derived eicosanoids on HT-29 cell proliferation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.995-1000
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• 2004

This study was purposed to investigate the effect of Gamgung-tang(GGT) on immune responses induced by glucocorticoid in mice. GGT solution was treated by intraperitoneal injection for 7 days after glucocorticoid treatment(80㎎/㎏). And then B and T cell proliferation and cytolytic activity of natural killer(NK) cells were measured. There was 25% inhibition in B cell proliferation with treatment of glucocorticoid. However, B cell proliferation was not influenced by GGT treatment. T cell proliferation was also inhibited by 18.4% with treatment of glucocorticoid. On the other hand, T cell proliferation was increased dose-dependent manner in GGT treated group. Furthermore in purified T cell, the proliferation was furtherly increased than non-purified T cell. At concentration of 18㎎/mouse GGT, purified T cell proliferation was increase to above level of normal group. The cytotoxic activity of NK cell was decreased by 35.3% with treatment of glucocorticoid. In GGT treated group, the cytotoxic activity of NK cell was increased to the normal level. In purified NK cell, the cytolytic activity of NK cell was further increased than non-purifed NK cell. These results suggest that GGT may proliferate T cell that is suppressed by glucocorticoid, and activate NK cell activity.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.3
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• pp.169-175
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• 2022

Bovine mammary epithelial (MAC-T) cells are commonly used to study mammary gland development and mastitis. Lipopolysaccharide is a major bacterial cell membrane component that can induce inflammation. Autophagy is an important regulatory mechanism participating in the elimination of invading pathogens. In this study, we evaluated the mechanism underlying bacterial mastitis and mammary cell death following lipopolysaccharide treatment. After 24 h of 50 ㎍/mL lipopolysaccharide treatment, a significant decrease in the proliferation rate of MAC-T cells was observed. However, no changes were observed upon treatment of MAC-T cells with 10 ㎍/mL of lipopolysaccharide for up to 48 h. Thus, upon lipopolysaccharide treatment, MAC-T cells exhibit dose-dependent effects of growth inhibition at 10 ㎍/mL and death at 50 ㎍/mL. Treatment of MAC-T cells with 50 ㎍/mL lipopolysaccharide also induced the expression of autophagy-related genes ATG3, ATG5, ATG10, ATG12, MAP1LC3B, GABARAP-L2, and BECN1. The autophagy-related LC3A/B protein was also expressed in a dose-dependent manner upon lipopolysaccharide treatment. Based on these results, we suggest that a high dose of bacterial infection induces mammary epithelial cell death related to autophagy signals.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.1 s.32
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• pp.145-153
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• 2007

Objecgtive : The aim of present study was to investigate inhibition effect of Whakijogyung-Tang(WJT) on the tumor cell lines. This study estimated the cytotoxicity of WJT about viability of S-180 and NlH3T3. Methods : The cytotoxicity of WJT about viability of cells were tested using a colorimetric tetrazoliun assay(MTT assay) Results and Conclusion : 1. Water extract of WJT had $IC_{50}$ of 863 ${\mu}g/ml$ in S-180 cell lines, but cytotoxicity of NIH3T3 was not significant difference compare with S-180. 2. n-Hexane fraction of WJT had similar cytotoxicity between S-180 and NIH3T3, but that could not have $IC_{50}$ in S-180 cell lines. 3. Ethyl acetate fraction of WJT had low degree cytotoxicity both S-180 and NIH3T3 cell lines. 4. Significantly, Butanol fraction of WJT had differenct citotoxicity between S-180 and NIH3T3. 5. $H_2O_2$ fraction of WJT had no cytotoxicity both S-180 and NIH3T3.

• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.97-104
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• 1997

For 16 years after the finding of HIV as an agent of AIDS in 1981, HIV therapeutic drugs of reverse transcriptase inhibitors (AZT, ddI, ddC, d4T) and protease inhibitors have been developed. Recent studies also were focused on a combination therapy by using HIV therapeutic drugs or natural compounds. Korean red ginseng (KRG) of natural compounds has been well known as a good reinforcement agent in Asia. The percentage of CD3+CD4+ T cell in nine HIV-infected patients without KRG treatment averaged 17.8% on baseline and decreased 15.8% after 6 months, whereas the percentage of the cell in fifteen HIV-infected patients with KRG treatment averaged 15.3% on baseline and increased up to 18.9% after the same period. The average percentage of CD3+CD8+ T cell of KRG-nontreated and KRG-treated HIV patients increased after 6 months 47.8% to 50.7% and 44.7% to 51.4%, respectively; and the average percentage of B and NK cell in the KRG-nontreated and KRG-treated HIV patients decreased 9.4% to 7.9% and 13.0% to 9.7%, 8.9% to 8.5% and 16.2% to 11.6%, respectively. KRG, therefore, didn't have any effects on the CD3+CD8+ T cell, B cell, and NK cell. However, it seems that KRG has a potential activity for stimulatiing the CD3+CD4+ T cell and some inhibition on destroying of this cell with no significance.

• Journal of Life Science
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• v.16 no.4
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• pp.589-597
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• 2006

Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase activities. There are several studies documenting molecular alterations leading to cell cycle arrest and induction of apoptosis by genistein as a chemopreventive agent in a variety of cancer cell lines; however, its mechanism of action and its molecular targets on human bladder carcinoma and leukemic cells remain unclear. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of T24 bladder carcinoma and U937 leukemic cells. Genistein significantly inhibited the cell growth and induced morphological changes, and induced the G2/M arrest of the cell cycle in both T24 and U937 cells with a relatively stronger cytotoxicity in U937. The G2/M arrest in T24 cells was associated with the inhibition of cyclin A, cyclin B1 and Cdc25C protein expression without alteration of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21(WAF1/CIP1). However, the inhibitory effects of genistein on the cell growth of U937 cells were connected with a marked inhibition of cyclin B1 and an induction of Cdk inhibitor p21 proteins by p53-independent manner. These data suggest that genistein may exert a strong anticancer effect and additional studies will be needed to evaluate the different mechanisms between T24 and U937 cells.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.184-193
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• 2013

Co-signaling molecules are surface glycoproteins that positively or negatively regulate the T cell response to antigen. Co-signaling ligands and receptors crosstalk between the surfaces of antigen-presenting cells (APCs) and T cells, and modulate the ultimate magnitude and quality of T cell receptor (TCR) signaling. In the past 10 years, the field of co-signaling research has been advanced by the understanding of underlying mechanisms of the immune modulation led by newly identified co-signaling molecules and the successful preclinical and clinical trials targeting co-inhibitory molecules called immune checkpoints in the treatment of autoimmune diseases and cancers. In this review, we briefly describe the characteristics of well-known B7 co-signaling family members regarding the expression, functions and therapeutic implications and to introduce newly identified B7 members such as B7-H5, B7-H6, and B7-H7.