• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1253-1257
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• 2004

6-Methoxydihydrosanguinarine (6ME), a benzophenanthridine alkaloid derived from the methanol extracts of Hylomecon hylomeconoides, showed a dose-dependent effect at 1-10 ${\mu}M$ on causing apoptotic cell death in HT29 colon carcinoma cells $(IC_{50} = 5.0{\pm}0.2 {\mu}M)$. Treatment of HT-29 cells with 6ME resulted in the formation of internucleosomal DNA fragmentation. Treatment of the cells with 6ME caused activation of caspase-3, -8 and 9 protease and subsequent proteolytic cleavage of poly(ADP-ribose)polymerase. 6ME increased the expression of p53 and Bax and decreased the expression of Bid. These results indicate that p53 and proapoptotic Bcl-2 family proteins might participate in the antiproliferative activity of 6ME in HT29 cells.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.6
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• pp.579-589
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• 2017

Anesthetics are used extensively in surgeries and related procedures to prevent pain. However, there is some concern regarding neuronal degeneration and cognitive deficits arising from regular anesthetic exposure. Recent studies have indicated that brain-derived neurotrophic factor (BDNF) and cyclic AMP response element-binding protein (CREB) are involved in learning and memory processes. Genistein, a plant-derived isoflavone, has been shown to exhibit neuroprotective effects. The present study was performed to examine the protective effect of genistein against isoflurane-induced neurotoxicity in rats. Neonatal rats were exposed to isoflurane (0.75%, 6 hours) on postnatal day 7 (P7). Separate groups of rat pups were orally administered genistein at doses of 20, 40, or 80 mg/kg body weight from P3 to P15 and then exposed to isoflurane anesthesia on P7. Neuronal apoptosis was detected by TUNEL assay and FluoroJade B staining following isoflurane exposure. Genistein significantly reduced apoptosis in the hippocampus, reduced the expression of proapoptotic factors (Bad, Bax, and cleaved caspase-3), and increased the expression of Bcl-2 and Bcl-xL. RT-PCR analysis revealed enhanced BDNF and TrkB mRNA levels. Genistein effectively upregulated cAMP levels and phosphorylation of CREB and TrkB, leading to activation of cAMP/CREB-BDNF-TrkB signaling. PI3K/Akt signaling was also significantly activated. Genistein administration improved general behavior and enhanced learning and memory in the rats. These observations suggest that genistein exerts neuroprotective effects by suppressing isoflurane-induced neuronal apoptosis and by activating cAMP/CREB-BDNF-TrkB-PI3/Akt signaling.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.853-856
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• 2005

Inductively coupled plasma reactive ion etching of magnetic tunnel junction (MTJ) stack, which is one of the key elements in magnetic random access memory, was studied. The MTJ stacks were patterned in nanometer size by electron(e)-beam lithography, and TiN thin films were employed as a hard mask. The etch process of TiN hard mask was examined using Ar, $Cl_2/Ar$, and $SF_6/Ar$. The TiN hard mask patterned by e-beam lithography was first etched and then the etching of MTJ stack was performed. The MTJ stacks were etched using Ar, $Cl_2/Ar$, and $BCl_3/Ar$ gases by varying gas concentration and pressure.

• Hanyang Medical Reviews
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• v.33 no.1
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• pp.10-16
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• 2013

Follicular helper T cells (Tfh) play a significant role in providing T cell help to B cells during the germinal center reaction, where somatic hypermutation, affinity maturation, isotype class switching, and the differentiation of memory B cells and long-lived plasma cells occur. Antigen-specific T cells with IL-6 and IL-21 upregulate CXCR5, which is required for the migration of T cells into B cell follicles, where these T cells mature into Tfh. The surface markers including PD-1, ICOS, and CD40L play a significant role in providing T cell help to B cells. The upregulation of transcription factor Bcl-6 induces the expression of CXCR5, which is an important factor for Tfh differentiation, by inhibiting the expression of other lineage-specific transcription factors such as T-bet, GATA3, and RORγt. Surprisingly, recent evidence suggests that CD4 T cells already committed to Th1, Th2, and Th17 cells obtain flexibility in their differentiation programs by downregulating T-bet, GATA3, and RORγt, upregulating Bcl-6 and thus convert into Tfh. Limiting the numbers of Tfh within germinal centers is important in the regulation of the autoantibody production that is central to autoimmune diseases. Recently, it was revealed that the germinal center reaction and the size of the Tfh population are also regulated by thymus-derived follicular regulatory T cells (Tfr) expressing CXCR5 and Foxp3. Dysregulation of Tfh appears to be a pathogenic cause of autoimmune disease suggesting that tight regulation of Tfh and germinal center reaction by Tfr is essential for maintaining immune tolerance. Therefore, the balance between Tfh and Tfr appears to be a critical peripheral tolerance mechanism that can inhibit autoimmune disorders.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.43.2-43.2
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• 2007

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• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1257-1264
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• 2016

Extracts from Artemisia annua $Linn\acute{e}$ (AAE) have various functions (anti-malaria, anti-virus, and anti-oxidant). However, the mechanism of the effects of AAE is not well known. Thus, we determined the apoptotic effects of AAE in AGS human gastric carcinoma cells. In this study, we suggested that AAE may exert cancer cell apoptosis through the Akt/mammalian target of rapamycin (mTOR)/glycogen synthase kinase (GSK)-$3{\beta}$ signal pathway and mitochondria-mediated apoptotic proteins. Activation by Akt phosphorylation resulted in cell proliferation through phosphorylation of tuberous sclerosis complex 2 (TSC2), mTOR, and GSK-$3{\beta}$. Thus, de-phosphorylation of Akt inhibited cell proliferation and induced apoptosis through inhibition of Akt, mTOR, phosphorylation of GSK-$3{\beta}$ at serine9, and control of Bcl-2 family members. Inhibition of GSK-$3{\beta}$ attenuated loss of mitochondrial membrane potential and release of cytochrome C. Bax and pro-apoptotic proteins were activated by their translocation into mitochondria from the cytosol. Translocation of Bax induced outer membrane transmission and generated apoptosis through cytochrome C release and caspase activity. We also measured 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, lactate dehydrogenase assay, Hoechst 33342 staining, Annexin V-PI staining, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide staining, and Western blotting. Accordingly, our study showed that AAE treatment to AGS cells resulted in inhibition of Akt, TSC2, GSK-$3{\beta}$-phosphorylated, Bim, Bcl-2, and pro-caspase 3 as well as activation of Bax and Bak expression. These results indicate that AAE induced apoptosis via a mitochondrial event through regulation of the Akt/mTOR/GSK-$3{\beta}$ signaling pathways.

• Tuberculosis and Respiratory Diseases
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• v.58 no.1
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• pp.43-53
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• 2005

Emphysema is characterized by air space enlargement and alveolar destruction. The mechanism responsible for the development of emphysema was thought to be protease/antiprotease imbalance and oxidative stress. A very recent study shows that alveolar cell apoptosis causes lung destruction and emphysematous changes. Thus, this study was performed to support the evidence for the role of apoptosis in the development of emphysema by characterizing cigarette smoke extract (CSE)-induced apoptosis in A549 (type II pneumocyte) lung epithelial cells. CSE induced apoptosis at low concentration (10% or less) and both apoptosis and necrosis at high concentration (20%). Apoptosis was demonstrated by DNA fragmentation using FACScan for subG1 fraction. Discrimination between apoptosis and necrosis was done by morphologic analysis using fluorescent microscopy with Hoecst 33342/propium iodide double staing and electron microscopy. Cytochrome c release was confirmed by using immunofluorescence with monoclonal anti-cytochrome c antibody. However, CSE-induced cell death did not show the activation of caspase 3 and was not blocked by caspase inhibitors. This suggests that CSE-induced apoptosis might be caspase-independent apoptosis. CSE-induced cell death was near completely blocked by N-acetylcystein and bcl-2 overexpression protected CSE-induced cell death. This results suggests that CSE might induce apoptosis through intracellular oxidative stress. CSE also activated p53 and functional knock-out of p53 using stable overexpression of HPV-E6 protein inhibited CSE-induced cell death. The characterization of CSE-induced cell death in lung epithelial cells could support the role of lung cell apoptosis in the pathogenesis of emphysema.

• Journal of Acupuncture Research
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• v.31 no.4
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• pp.57-70
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• 2014

Objectives : The purpose of this study is to examine if Clematidis Radix(CR) pharmacopuncture may be effective to the neuropathic pain(mechanical allodynia) in a rat model of neuropathic pain. Methods : To produce the model of neuropathic, L5 spinal nerve was ligated by 6-0 silk thread. After neuropathic surgery, the author examined if the animals exhibited the plantar withdrawal response of allodynia. The plantar withdrawal response was assessed by dynamic plantar aesthesiometer three days after the neuropathic surgery, CR pharmacopuncture was injected at $BL_{23}$ 1time/week for 6 weeks. After that, the author examined the plantar withdrawal response of rats' leg by dynamic plantar aesthesiometer. And also the author examined mGluR5, Bax, Bcl-2, Bax/Bcl-2 ratio in spinal cord, and c-Fos. Also the author observed the change of aspartate aminotransferase(AST), alanine aminotransferase(ALT) count in the blood serum of neuropathic rats. Results : 1. The withdrawal response of allodynia decreased in the PT3, PT4 group as compared with control group. 2. The mGluR5 increased in the PT1, PT2, PT3, and PT4 group. 3. The Bax and Bax/Bcl-2 ratio decreased in the PT4 group. 4. The c-Fos increased in the PT1 group, and decreased in the PT4 group. 5. The changes of AST in blood serum decreased in the every group excluded control group and the changes of ALT in blood serum isn't shown the signigicant change. Conclusions : These results are suggested that CR pharmacopuncture at BL23 decreased mechanical allodynia, can act on anti-apoptotic, neuroprotective effects and liver fuction in the model of neuropathic pain.

• IMMUNE NETWORK
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• v.6 no.2
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• pp.59-66
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• 2006

Background: CM1 (Centrocyte/-blast Marker I) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on a subpopulation of centroblasts and centrocytes of human germinal center (GC) B cells. Burkitt lymphoma (BL) is a tumor consisting of tumor cells with the characteristics of GC B cell. Previously we reported that CM1 ligation with anti-CM1 mAb induced apoptosis in Ramos $(IgM^{high})$ and Raji $(IgM^{low})$ cells. Methods & Results: In the present study, we observed that CM1 ligation with anti-CM1 mAb induced Fas ligand and Fas expression in Ramos cells, but not in Raji cells. Furthermore, anti-Fas blocking antibody, ZB4, blocked CM1-mediated apoptosis effectively in Ramos cells, but not in Raji cells. Increased mitochondrial membrane permeabilization, which was measured by $DiOC_6$, was observed only in Raji cells. In contrast to no significant change of Bax known as pro-apoptotic protein, anti-apoptotic protein Bcl-2 was significantly decreased in Raji cells. In addition, we observed that CM1 ligation increased release of mitochondrial cytochrome c and upregulated caspase-9 activity in Raji cells. Conclusion: These results suggest that apoptosis induced by CM1-ligation is mediated by Fas-Fas ligand interaction in Ramos cells, whereas apoptosis is mediated by down-regulation of Bcl-2 and subsequent decrease of mitochondrial membrane potential in Raji cells.

• Journal of Life Science
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• v.22 no.6
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• pp.815-822
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• 2012

Piceatannol (trans-3,4,3',5'-tetrahydroxystilbene), a natural stilbene, is an analogue of resveratrol. Although recent experimental data have revealed the health benefit potency of piceatannol, the molecular mechanisms underlying the anti-cancer activity have not yet been studied in detail. In the present study, the further possible mechanisms by which piceatannol exerts its pro-apoptotic action in cultured human lung cancer A549 cells were investigated. Exposure of A549 cells to piceatannol resulted in growth inhibition and induction of apoptosis. Apoptosis induction of A549 cells by piceatannol showed correlation with proteolytic activation of caspase-3, -8, and -9, and concomitant degradation of activated caspase-3 target proteins such as poly (ADP-ribose) polymerase, phospholipase C-${\gamma}1$, ${\beta}$-catenin, and Inhibitor caspase-activated DNase. The increase in apoptosis by piceatannol treatment was also associated with an increase of pro-apoptotic Bax expression and decrease of anti-apoptotic Bcl-2 and Bcl-xL expression, and caused down-regulation of the inhibitor of apoptosis protein family members and up-regulation of Fas and Fas legend. In addition, piceatannol treatment markedly inhibited the expression of mRNA and proteins of inducible nitric oxide (NO) synthase, and the levels of NO production were progressively down-regulated by piceatannol treatment in a dose-dependent fashion. The results indicate that piceatannol may have therapeutic potential against human gastric cancer cells.