• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7995-8001
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• 2014

Interferon-gamma (IFN-${\gamma}$) has been used to treat various malignant tumors. However, the molecular mechanisms underlying the direct anti-proliferative activity of IFN-${\gamma}$ are poorly understood. In the present study, we examined the in vitro antitumor activity of IFN-${\gamma}$ on two human non-small-cell lung carcinoma (NSCLC) cell lines, H322M and H226. Our findings indicated that IFN-${\gamma}$ treatment caused a time-dependent reduction in cell viability and induced apoptosis through a FADD-mediated caspase-8/tBid/mitochondria-dependent pathway in both cell lines. Notably, we also postulated that IFN-${\gamma}$ increased indoleamine 2,3-dioxygenase (IDO) expression and enzymatic activity in H322M and H226 cells. In addition, inhibition of IDO activity by the IDO inhibitor 1-MT or tryptophan significantly reduced IFN-${\gamma}$-induced apoptosis and death receptor 5 (DR5) expression, which suggests that IDO enzymatic activity plays an important role in the anti-NSCLC cancer effect of IFN-${\gamma}$. These results provide new mechanistic insights into interferon-${\gamma}$ antitumor activity and further support IFN-${\gamma}$ as a potential therapeutic adjuvant for the treatment of NCSLC.

• Biomedical Science Letters
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• v.15 no.3
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• pp.179-185
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• 2009

In our previous report, we showed that $PPAR{\gamma}$ does not influence adipogenesis in females with functioning ovaries, indicating that $PPAR{\gamma}$ activity on adipogenesis is associated with sex-related factors. Among the sex-related factors, estrogen has been recognized as a major factor in inhibiting adiposgenesis in females. Thus, we hypothensized that $17{\beta}$-estradiol (E) inhibits 3T3-L1 cell adipogenesis by preventing $PPAR{\gamma}$ activity. E decreased triglyceirde accumulation in differentiated 3T3-L1 cells compared with control group. E also decreased the expression of $PPAR{\gamma}$ mRNA as well as $PPAR{\gamma}$ dependent adipocyte-specific genes, such as adipocyte fatty acid binding protein and tumor necrosis factor $\alpha$. In addition, E not only decreased luciferase reporter activity by $PPAR{\gamma}$, but also transfection of estrogen receptor $\alpha$ ($ER{\alpha}$) or $ER{\beta}$ led to decreases in $PPAR{\gamma}$ reporter gene activation. Moreover, E-activated ERs significantly decreased the luciferase reporter gene activation induced by $PPAR{\gamma}$ transfection, suggesting that estrogen-activated ERs inhibit $PPAR{\gamma}$-dependent transactivation. Accordingly, our results demonstrate that E inhibits the action of $PPAR{\gamma}$ on adipogenesis through E activated ER, providing evidence that lack of estrogen may potentiate $PPAR{\gamma}$ action on adipogenesis.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.230-238
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• 2004

The adverse health effects of a number of environment pollutions are related to the formation of free radicals. Induction of antioxidant defensive system in the response to an oxidative attack is an essential element of the cell to survive. CYP2E1 is easily induced by organic solvents and induces continuous formation of reactive oxygen species (ROS). ${\gamma}$-Glutamyltranspeptidase (${\gamma}$GT) plays an important role in glutathione metabolism and xenobiotic detoxification. To evaluate the characteristic of oxidative stress which induces GGT expression and to understand human antioxidant defensive response against oxidative stress induced by CYP2E1, we studied regulation of ${\gamma}$GT enzyme expression in response to various oxidative stresses in human HepG2 cells. The ${\gamma}$GT activity was not modified after exposure of acute oxidative stress inducing agents (ferric nitrilotriacetate, cumene hydroperoxide, ADP-Fe, O-tetradecanoylphorbol-13-acetate, tumor necrosis factor-alpha). To induce continuous exposure of cells to ROS, HepG2 cells were transfected by human CYP2E1 gene transiently. The CYP2E1 activity was verified with chlorzoxazone hydroxylation. Transfection of CYP2E1 showed continuous 60% increase in intracellular ROS and 240 % increase in microsomal ROS. CYP2E1 overexpressing cells showed increased ${\gamma}$GT activity (2.5-fold). The observed enhancement of ${\gamma}$GT activity correlated with a significant increase of ${\gamma}$GT mRNA (2.1-fold). Treatment with antioxidant strongly prevented the increase in ${\gamma}$GT activity. The CYP2E1 overexpression did not modify toxicity index and increased glutathione levels. These results show that continuous exposure of cells to ROS produced by CYP2E1 up-regulates ${\gamma}$GT; This may be one of the adaptive antioxidant responses of cells to oxidative insult. Present study also suggests that the induction of ${\gamma}$GT could be used as a marker of oxidative stress induced by exposure to organic solvents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.232-237
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• 1999

The relationship between structure and contractile activity was studied on the three neuropeptide $\gamma$ (mammalian-, bowfin-, shark-NP$\gamma$) that were synthesized by the solid-phase method. Circular dichroism spectra showed that mammalian-, bowfin- and shark-neuropeptide $\gamma$ took an unordered structure in buffer solution and artificial liposome. The intestinal motility response was investigated with guinea-pig ileum, rat duodenum and carp intestine. In case of carp intestine, contractile activity was as follows; bowfin-NP$\gamma$> shark-NP$\gamma$>mammalian-NP$\gamma$, On the other hand, the contractile activity of mammalian-neuropeptide $\gamma$ was more potent than those of bowfin-, shark-neuropeptide $\gamma$ in the guinea-pig ileum and rat duodenum. These results suggest that NP$\gamma$ show the species-specific activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.244-251
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• 1997

The relationship between structure and biological activity was studied on the three neuropeptides (mammalian, trout- and goldfish-neuropeptide $\gamma$) that were syntheized by the solid-phase method. Circular dichroism spectra showed that mammalian, trout- and goldfish-neuropeptide $\gamma$ adopted an unordered structure in buffer solution. In the-presence of neutral and acidic liposomes, mammalian and trout-neuropeptioe $\gamma$ also took a random structure. However, goldfish-neuropeptide $\gamma$ took an $\alpha-helical$ structure in acidic liposomes. The intestinal motility response was investigated with carp intestines, guinea-pig ileums and rat duodenums. In case of carp intestine, contractile activity was as follows : goldfish-neuropeptide $\gamma\simeq$ trout-neuropeptide $\gamma>$ mammalian-neuropeptide $\gamma$, On the other hand, the contractile activity of mammalian-neuropeptide $\gamma$ was more potent than trout- and goldfish-neuropeptide $\gamma$ in the guinea-pig ileums and rat duodenums. These results suggest that neuropeptide $\gamma$ show the species-specific activity.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.380.2-380.2
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• 2002

Peroxisome proliferator-activated receptor (PPAR)-$\gamma$ is a nuclear hormone receptor family that plays an important role in the transcriptional regulation of genes in cellular lipid and energy metabolism. In our search for Iigands for PPAR-$\gamma$ from natural resources. two phenylpropanoids. 3.4.5-Trimethoxy cinnamylalcohol (1) and 3.4.5- Trimethoxy cinnamaldehyde (2). were isolated as PPAR-$\gamma$ agonists from the MeOH extracts of Zanthoxylum schinifolium Sieb. & ZUCCo (Rutaceae) by activity-guided fractionation. These two compoundS bind and activated PPAR-$\gamma$ transcriptional activity in a dose dependent manner assessed by ligand-binding assay. While the maximum activities for PPAR-$\gamma$ of these compounds were comparable with that of rosiglitazone. which is currently used in the treatment of Type II diabetes. the potency of these compounds were much weaker than rosiglitazone ($ED_{50}$=t.2$\mu\textrm{M}$) with the $ED_{50}$ values of 9.08 and 4.08 $\mu\textrm{M}$. respectively. To examine the structure-activity relationship of phenylpropanoids. we prepared several phenylpropanoid derivatives and measured the activity. We observed that substituents at 4'- position could playa key role in determining the potency for PPAR-$\gamma$ agonistic activity .

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.499-504
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• 2012

We analyzed the contents of ${\gamma}$-oryzanol, which is contained in brown rice of the nation rice varieties Chucheong, Heukjinju and Sindongjin, by HPLC. Furthermore we also performed experiments on its biological activity, to prove the effectiveness of rice bran. The contents of ${\gamma}$-oryzanol contained in hulled rice showed 1,587 ppm for Heukjinju, followed by Chucheong(1,038 ppm), and by Sindongjin(472 ppm). In anti-oxidative activity, we performed an experiment, by measuring the radical scavenging activity of DPPH. Heukjinju showed the best effect, and Chucheong showed the worst effect. In cholesterol lowering activity, Heukjinju showed the best activity and Sindongjin showed the worst effect. In anti-bacterial activity as well, Heukjinju showed the best activity, and Sindongjin showed the worst effect. Through these experiments, we compared the contents of ${\gamma}$-oryzanol, which is contained in hulled rice(Chucheong, Heukjinju, Sindongjin). Also, we found the anti-oxidation effect, cholesterol lowering effect, and anti-bacterial activity of the ${\gamma}$-oryzanol extracts. Based on our research, we expect that ${\gamma}$-oryzanol can work as a new drug, or nutritional supplement.

• Biomedical Science Letters
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• v.12 no.4
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• pp.419-425
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• 2006

Phospholipase $C-{\gamma}1\;(PLC-{\gamma}1)$ is an important signaling molecule for cell proliferation and differentiation. $PLC-{\gamma}1$ contains two pleckstrin homology (PH) domains, which are responsible for protein-protein interaction and protein-lipid interaction. $PLC-{\gamma}1$ also has two Src homology (SH)2 domains and a SH3 domain, which are responsible for protein- protein interaction. To identity proteins that specifically binds to PH domain of $PLC-{\gamma}1$, we prepared and incubated the glutathione S-transferase(GST)-fused PH domains of $PLC-{\gamma}1$ with COS7 cell lysate. We found that 90 kDa protein specifically binds to PH domain of $PLC-{\gamma}1$. By matrix-assisted laser desorption ionization time of flight-mass spectrometry, the 90 kDa protein revealed to be heat shock protein (Hsp) $90{\beta}$. Hsp $90{\beta}$ is a molecular chaperone that stabilizes and facilitates the folding of proteins that are involved in cell signaling, including receptors for steroids hormones and a variety of protein kinases. To know whether Hsp $90{\beta}$ affects on $PLC-{\gamma}1$ activity, we performed $PIP_2$ hydrolyzing activity of $PLC-{\gamma}1$ in the presence of purified Hsp $90{\beta}$ in vitro. Our results show that the Hsp $90{\beta}$ dose-dependently inhibits the enzymatic activity of $PLC-{\gamma}1$ and further suggest that Hsp $90{\beta}$ regulates cell growth and differentiation via regulation of $PLC-{\gamma}1$ activity.

• Journal of Radiation Industry
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• v.5 no.2
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• pp.165-168
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• 2011

The antioxidant activity was analyzed in gamma-irradiated cooking juices. Because the activities of antioxidants have been attributed to various mechanisms, different assay methods including 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP), have been conducted and compared. All of these antioxidant assay showed that the antioxidant activity of cooking juice was increased by gamma-irradiation. To investigate this increase of antioxidative activity, the protein was extracted from cooking juices and its antioxidant activity was measured. From the results, it was thought that the modification of protein in cooking juiced by irradiation caused the increase of antioxidant activity of cooking juice. Therefore, gamma irradiation could be an promising method for a sterilization of cooking juice with increased antioxidant activity.

• KSBB Journal
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• v.26 no.6
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• pp.565-568
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• 2011

In this study, it was investigated the antioxidant activity of laminarin degraded by gamma irradiation. Because the activities of antioxidants have been attributed to various mechanisms, different assay methods have been conducted and compared. 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power, and lipid peroxidation inhibitory activity of degraded laminarin were measured and compared with non-degraded. All of these results showed that the antioxidant activity of laminarin degraded by irradiation was increased depending on the absorbed dose. Therefore, gamma irradiation could be an alternative method for the preparation of degraded laminarin with higher antioxidant activity.