• Archives of Pharmacal Research
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• v.29 no.8
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• pp.633-644
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• 2006

In last couple of decades the use of natural compounds like flavonoids as chemopreventive agents has gained much attention. Our current study focuses on identifying chemopreventive flavonoids and their mechanism of action on human prostate cancer cells. Human prostate cancer cells (PC3), stably transfected with activator protein 1 (AP-1) luciferase reporter gene were treated with four main classes of flavonoids namely flavonols, flavones, flavonones, and isoflavones. The maximum AP-1 luciferase induction of about 3 fold over control was observed with $20\;{\mu}M$ concentrations of quercetin, chrysin and genistein and $50\;{\mu}M$ concentration of kaempferol. At higher concentrations, most of the flavonoids demonstrated inhibition of AP-1 activity. The MTS assay for cell viability at 24 h showed that even at a very high concentration $(500\;{\mu}M)$, cell death was minimal for most of the flavonoids. To determine the role of MAPK pathway in the induction of AP-1 by flavonoids, Western blot of phospho MAPK proteins was performed. Four out of the eight flavonoids namely kaempferol, apigenin, genistein and naringenin were used for the Western Blot analysis. Induction of phospho-JNK and phospho-ERK activity was observed after two hour incubation of PC3-AP1 cells with flavonoids. However no induction of phospho-p38 activity was observed. Furthermore, pretreating the cells with specific inhibitors of JNK reduced the AP-1 luciferase activity that was induced by genistein while pretreatment with MEK inhibitor reduced the AP-1 luciferase activity induced by kaempferol. The pharmacological inhibitors did not affect the AP-1 luciferase activity induced by apigenin and naringenin. These results suggest the possible involvement of JNK pathway in genistein induced AP-1 activity while the ERK pathway seems to play an important role in kaempferol induced AP-1 activity.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.3
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• pp.1-12
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• 2012

Objectives : Fagopyrum esculentum(FE) has been used for removal of inflammation of internal organs and treatment of sore and ulcer by heat toxin in Korean herbal medicines. In this study, To investigated the protective effect of FE on allergic response, we determined whether FE inhibits allergic response. Methods : The effect of FE was analyzed by ELISA, RT-PCR and Western blot in RBL-2H3 cells. We investigated cell viability, ${\beta}$-hexosaminidase, as a marker of degranulation, cytokne, and intracellular ROS and MAPK and NF-${\kappa}B$ signaling. Results : We found that FE suppressed ${\beta}$-hexosaminidase release, the production of IL-4 and TNF-${\alpha}$ and intracellular ROS level in RBL-2H3 by the anti-DNP IgE plus DNP-HSA stimulation. FE also significantly inhibited cytokine mRNA expressions, such as IL-$1{\beta}$, IL-2, IL-3, IL-4, IL-5, IL-6, IL-13, TNF-${\alpha}$ and GM-CSF in RBL-2H3. In addition, PF suppressed the phospholyation of ERK1/2, JNK1/2, p38 and $I{\kappa}B{\alpha}$ and NF-${\kappa}B$ signal transduction pathway. Conclusions : Our results indicate that FE protects against allergic response and exerts an anti-inflammatory effect through the inhibition of degranulation and production of cytokines and ROS via the suppression MAPK and NF-${\kappa}B$ of signal transduction. Abbrevations : FE, Fagopyrum esculentum; RBL-2H3, rat basophilic leukemia cell line; ROS, reactive oxygen species; MAPK, Mitogen-activated protein kinase; $NF{\kappa}B$, nuclear factor ${\kappa}B$; $TNF{\alpha}$, Tumor necrosis factor alpha; GM-CSF, Granulocyte macrophage colony-stimulating factor; ERK, extracellular-signal-regulated kinase; JNK, c-Jun NH2-terminal kinase; p38, p38 MAP kinase; $I{\kappa}B{\alpha}$, inhibitory-kappa B alpha.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.115-121
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• 1988

Although Saponin A from Panax ginseng has previously been shown to inhibit carageenin induced edema. a paucity of information exists on the effects of components from ginseng on the cellular inflammatory response. specifically polymorphonuclear leukocyte (PMNL) function. The purpose of this study was 10 determine the effects of isolated neutral dammarane saponins from ginseng (i.e..glycosidic derivatives of 20(S)-protopanaxadiol [ginsenoside $Rb_1,\;Rb_2$ and Rc] and 20(S)-protopanaxatriol [ginsenosides Re and $Rg_1$]) on in vivo PMNL function and to compare their effects with those produced by a steroidal anti-inflammatory agent (dexamethasone) and commercially available saponin. Dexamethasone. the ginsenosides and saponin were all shown to he potent inhibitors of PMNL chemotaxis using the $^{51}Cr$ assay with $5{\times}10^{-8}M$ f-met-leu-phe [FMLP] as the chemoattractant. Inhibition or PMNL chemotaxis by dexamethasone. the ginsenosides and saponin were all shown to be both time-and dose-dependent and these agents did not affect cellular viability at the concentrations tested Saponin and the ginsenosides were more potent inhibitors of chemotaxis than was dexamethasone. while oxidant generation (as measured by the luminol-enhaneed chemil-uminescence of PMNL using FMNL $[10^{-6}]$ as the stimulus) was inhibited by dexamethasone. the ginsenosides $(Rb_1\;Rb_2\;Rc\;Re\;and\;Rg_1)$ and saponin at a concentration of 1 ${\mu}M$ had no significant effect on PMNL chemiluminescence. Thus. the neutral dammarane saponins are potentially important modulators or PMNL function and their inhibitory effects may he differentiated from those of the Steroidal anti-inflammatory agents.

• Journal of Life Science
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• v.17 no.11
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• pp.1596-1600
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• 2007

Bee venom is used to treat inflammatory diseases in Korean traditional medicine and has been known to inhibit proliferation and induce apoptosis in cancer cells. However, the molecular mechanisms involved in bee venom-induced apoptosis are still uncharacterized in human lung cancer cells. In the present study, we investigated the effects of bee venom on the apoptosis of A549 human lung epithelial cancer cells. Treatment of bee venom inhibited the cell viability and induced apoptosis in a concentration-dependent manner as measured by hemocytometer counts, fluorescence microscopy and flow cytometry analysis. Bee venom-induced apoptosis in A549 cells was associated with a marked inhibition of anti-apoptotic Bcl-2 expression without significant changes in the levels of Bax and Bcl-xL. Bee venom treatment also inhibited the levels of IAP family members such as cIAP-1 and cIAP-2 and induced the proteolytic activation of caspase-3 and caspase-9. Although further studies are needed, the present results suggest that apoptotic signals evoked by bee vemon in A549 cancer cells may converge caspases activation through a down-regulation of Bcl-2 rather than an up-regulation of Bax. These findings provide important insights into the possible molecular mechanisms of the anti-cancer activity of bee vemon in human cancer cells.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.165-171
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• 2006

ERM proteins transfer the methyl group to $A_{2058}$ in 23S rRNA to confer the resistance to MLS (macrolide-lincosamide-streptogramin B) antibiotics on microorganism ranging from antibiotic producers to pathogens. To define the functional role of peptide segment encompassing amino acid residues 1 to 25 in NTER (N-terminal end region) of ErmSF, one of the ERM proteins, DNA fragment encoding mutant protein deprived of that peptide was cloned and overexpressed in E. coli to obtain a purified soluble form protein to the apparent homogeneity in the yield of 12.65 mg per liter of culture. The in vitro activity of mutant protein was found to be 85% compared to wild type ErmSF, suggesting that this peptide interact with substrate to affect the enzyme activity. This diminished activity of mutant protein caused the delayed expression of antibiotic resistance in vivo, that at fIrst cells expressing mutant protein showed the retarded growth due to the antibiotic action but with time cells inhibited by antibiotic gradually recovered the viability to exert the resistance to the same extent as those with wild type protein.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.626-632
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• 2005

The polyamines are essential components of all eukaryotic cells and absolutely necessary for cell growth. In the present study, the cytoprotective role of polyamine was characterized. When $Ac_2F$ rat liver cells were treated with 1M 2,2'-azobis (2-amidinopropane) dehydrochloride (AAPH), a water soluble free radical initiator, viability of the cells was noticeably decreased due to the increase of reactive oxygen species (ROS). The cytotoxic effect of AAPH as well as ROS generation were significantly inhibited by the treatment of polyamines. Among polyamines, especially spermine at $20{\mu}M$ concentration exerted over $45\%$ inhibition of AAPH-induced ROS generation. Western blotting was performed to determine whether superoxide dismutase(SOD) or catalase (CAT) expression was involved in oxidative stress. The AAPH treatment blocked both SOD and CAT protein expressions. Spermine could recover those protein expressions to the untreated control levels. According to the result of cycline E measurement, AAPH might block the entry of the cells into S phase of the cell cycle. The reduced expression of cyclin E protein could be fully recovered by the addition of spermine. The antioxidative effects of spermine was also further proved by the apopotitic morphological analysis using ethidium bromide and acridine orange.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.914-922
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• 2003

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 HL-60 human leukemia cell line. 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 HL-60 human leukemia cell line which delete wild type p53. G1 checkpoin related gene products tested (cyclin D3, cyclin dependent kinase 4, retinoblastoma, E2F1) 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 HL-60 human leukemia cell line

• Parasites, Hosts and Diseases
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• v.58 no.4
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• pp.393-402
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• 2020

Toxoplasma gondii is an intracellular parasite that causes severe disease when the infection occurs during pregnancy. Adenosine is a purine nucleoside involved in numerous physiological processes; however, the role of adenosine receptors in T. gondii-induced trophoblast cell function has not been investigated until now. The goal of the present study was to evaluate the intracellular signaling pathways regulated by adenosine receptors using a HTR-8/SVneo trophoblast cell model of T. gondii infection. HTR8/SVneo human extravillous trophoblast cells were infected with or without T. gondii and then evaluated for cell morphology, intracellular proliferation of the parasite, adenosine receptor expression, TNF-α production and mitogen-activated protein (MAP) kinase signaling pathways triggered by adenosine A₃ receptor (A₃AR). HTR8/SVneo cells infected with T. gondii exhibited an altered cytoskeletal changes, an increased infection rate and reduced viability in an infection time-dependent manner. T. gondii significantly promoted increased TNF-α production, A₃AR protein levels and p38, ERK1/2 and JNK phosphorylation compared to those observed in uninfected control cells. Moreover, the inhibition of A₃AR by A₃AR siRNA transfection apparently suppressed the T. gondii infection-mediated upregulation of TNF-α, A₃AR production and MAPK activation. In addition, T. gondii-promoted TNF-α secretion was dramatically attenuated by pretreatment with PD098059 or SP600125. These results indicate that A₃AR-mediated activation of ERK1/2 and JNK positively regulates TNF-α secretion in T. gondii-infected HTR8/SVneo cells.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.397-403
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• 2018

The leaves of Spiraea prunifolia were extracted with 80% aqueous MeOH and the concentrates were partitioned into EtOAc, n-BuOH, and $H_2O$ fractions. The repeated $SiO_2$ or ODS column, and medium pressure liquid chromatographies for the n-BuOH fraction led to isolation of two phenolic glucosides. The chemical structures of these compounds were determined as isosalicin (1) and crenatin (2) based on spectroscopic analyses including Nuclear magnetic resonance and MS. Extracts were analyzed using UPLC-MS/MS providing a short analysis time within 5 min using MRM technique. The concentration of crenatin was higher as 9.53 mg/g and isosalicin was lower as 0.65 mg/g. Neuroprotective effects of these compounds against hydrogen peroxide ($H_2O_2$)-induced neurotoxicity were evaluated. The results showed that exposure to $H_2O_2$ induced morphological changes, cell death and neurotoxicity in SK-N-MC cells. However, pretreatment with crenatin resulted in inhibition of morphological change, reduction of loss of cell viability and attenuation of neuronal damage. These results suggested that neuroprotective effect of crenatin isolated from S. prunifolia can be a good candidate for the development of health beneficial foods which can ameliorate the degenerative neuronal disease caused by oxidative stress.

• Journal of Life Science
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• v.28 no.11
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• pp.1316-1320
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• 2018

The effects of a green tea extract (GTE) were examined using the MCF-7 human breast cancer cell line. Cell viability assays using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays revealed that GTE had a significant cytotoxic effect on MCF-7 cells, depending on the concentration of GTE. Western blotting of p53 and its related proteins, p21/cip1 and CDK2, after GTE treatment revealed that a significant and concentration dependent increase in p53 protein in response to GTE. The levels of p21/cip1 proteins were also increased at low GTE concentrations were significantly increased even at the highest GTE concentrations. However, the level of CDK2 was significantly decreased by treatment with high concentrations of GTE. These results indicate that treatment with GTE increased the p53 level in MCF-7 cells, and this activation of p53 markedly elevated the levels of p21/cip1proteins, which, in turn, inhibited CDK2 expression in the MCF-7 cells. The inhibition of CDK2 expression might then affect cell cycle progression. Subsequent FACS analysis indicated that GTE treatment the gradually increased progression of the MCF-7 to the G1 phase. These results clearly demonstrate that the anti-tumor effect of GTE in MCF-7 cells is regulated by p53 arrest of the MCF-7 cells at the G1 stage of cell cycle.