• Molecules and Cells
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• v.27 no.1
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• pp.113-118
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• 2009

In this study, we have shown the transcriptional regulation of the human GD3 synthase (hST8Sia I) induced by valproic acid (VPA) in human neuroblastoma SK-N-BE(2)-C cells. To elucidate the mechanism underlying the regulation of hST8Sia I gene expression in VPA-stimulated SK-N-BE(2)-C cells, we characterized the promoter region of the hST8Sia I gene. Functional analysis of the 5'-flanking region of the hST8Sia I gene by the transient expression method showed that the -1146 to -646 region, which contains putative binding sites for transcription factors c-Ets-1, CREB, AP-1 and NF-${\kappa}B$, functions as the VPA-inducible promoter of hST8Sia I in SK-N-BE(2)-C cells. Site-directed mutagenesis and electrophoretic mobility shift assay indicated that the NF-${\kappa}B$ binding site at -731 to -722 was crucial for the VPA-induced expression of hST8Sia I in SK-N-BE(2)-C cells. In addition, the transcriptional activity of hST8Sia I induced by VPA in SK-N-BE(2)-C cells was strongly inhibited by SP600125, which is a c-Jun N-terminal kinase (JNK) inhibitor, and $G{\ddot{O}}6976$, which is a protein kinase C (PKC) inhibitor, as determined by RT-PCR (reverse transcription-polymerase chain reaction) and luciferase assays. These results suggest that VPA markedly modulated transcriptional regulation of hST8Sia I gene expression through PKC/JNK signal pathways in SK-N-BE(2)-C cells.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.272-279
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• 2006

$\underline{Purpose}$: This study investigated the influence of irradiation and cisplatin on PrxI & PrxII expression and on their survival rates (SR) in SK-N-BE2C and Rat2 cell lines. $\underline{Materials\;and\;Methods}$: The amount of PrxI & PrxII production with or without N-acetyl-L-cysteine (NAC) pretreatment was studied using a western blot after 20 Gy irradiation to determine the degree of inhibition of ROS accumulation. In addition, the amount of PrxI & PrxII production after cisplatin and after combination with cisplatin and 20 Gy irradiation was studied. The SRs of the cell lines in SK-N-BE2C and Rat 2 cells, applied with 20 Gy irradiation only, with various concentrations of cisplatin and with the combination of both, were studied. The 20 Gy irradiation-only group and the combination group were each subdivided according to NAC pretreatment, and corresponding SRs were observed at 2, 6, 12 and 48 hours after treatment. $\underline{Results}$: Compared with the control group, the amount of PrxI in SK-N-BE2C increased up to 60 minutes after irradiation and slightly increased after irradiation with NAC pretreatment 60 minutes. It did not increase in Rat2 after irradiation regardless of NAC pretreatment. PrxII in SK-N-BE2C and Rat2 was not increased after irradiation regardless of NAC pretreatment. The amounts of PrxI and PrxII in SK-N-BE2C and Rat2 were not increased either with the cisplatin-only treatment or the combination treatment with cisplatin and irradiation. SRs of irradiation group with or without NAC pretreatment and the combination group with or without NAC pretreatment were compared with each other in SK-N-BE2C and Rat2. SR was significantly high for the group with increased amount of PrxI, NAC pretreatment and lower the cisplatin concentration. SR of the group in SK-N-BE2C which had irradiation with NAC pretreatment tended to be slightly higher than the group who had irradiation without NAC pretreatment. SR of the group in Rat2 which had irradiation with NAC pretreatment was significantly higher than that the group which had irradiation without NAC pretreatment. Compared to the combination group, the irradiation-only group revealed statistically significant SR decrease with the maximal difference at 12 hours. However, at 48 hours the SR of the combination group was significantly lower than the irradiation-only group. $\underline{Conclusion}$: PrxI is suggested to be an antioxidant enzyme because the amount of PrxI was increased by irradiation but decreased pretreatment NAC, a known antioxidants. Furthermore, cisplatin may inhibit PrxI production which may lead to increase cytotoxicity of irradiation. The expression of PrxI may play an important role in cytotoxicity mechanism caused by irradiation and cisplatin.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.244-252
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• 1998

Ginsenoside Rh, (G-Rh,) from Panax ginseng induced morphological features of apoptosis and DNA fragmentation as a biochemical marker of apoptosis confirmed by TUNEL reaction and agarose gel electrophoresis in human neuroblastoma SK-N-BE(2) and rat glioma C6Bu-1 cells During apoptosis by G-Rh2, protein kinase C (PKC) isoforms were analysed by immunoblotting. In SK-N-BE(2) cells, the levels of a, p and ${\gamma}$ subtypes were increased by undergoing apoptosis, while PKC e isoform increased early in treatment (3 h and 6 h). In addition, PKC s isoform gradually decreased during apoptosis by G-Rh2 and PKC $\theta$ isoform was detected in neither untreated- nor G-Rh1-treated SK-N-BE(2) cells (data not shown). However, no significant changes in the level of S and s isoforms were observed in C6Bu-1 cells undergoing apoptosis by G-Rh2. These results suggest that PKC subtypes may play differential roles in apoptotic signal pathways and their roles can be cell type-specific in apoptosis induced by G-Rh2.

• Archives of Pharmacal Research
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• v.23 no.5
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• pp.518-524
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• 2000

We examined the modulation of protein kinase C (PKC) subtypes during apoptosis induced by ginsenoside Rh2 (G-Rh2) in human neuroblastoma SK-N-Bl(2) and rat glioma C6Bu-1 cells. Apoptosis induced by C-Rh2 in both cell lines was confirmed, as indicated by DNA fragmentation and in situ strand breaks, and characteristic morphological changes. During apoptosis induced by G-Rh2 in SK-N-BE(2) cells, PKC subtypes $\alpha$, $\beta$ and $\gamma$ were progressively increased with prolonged treatment, whereas PKC $\delta$ increased transiently at 3 and 6 h and PKC $\varepsilon$ was gradually down-regulated after 6 h following the treatment. On the other hand, PKC subtype $\beta$ markedly increased at 24 h when maximal apoptosis was achieved. In C6Bu-l cells, no significant changes in PKC subtypes $\alpha$, $\gamma$, $\delta$, $\varepsilon$ and $\beta$ were observed during apoptosis induced by G-Rh2. These results suggest the evidence for a possible role of PKC subtype in apoptosis induced by G-Rh2 in SK-N-BE(2) cells but not in C6Bu-1 cells, and raise the possibility that G-Rh2 may induce apoptosis via different pathways interacting with or without PKC in different cell types.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.3
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• pp.289-297
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• 2017

The objective of this study was to identify and compare the anti-diabetic effects of mulberry leave (ML), silkworm (SK), mulberry fruit (MF), and Cudrania tricuspidata BUREAU (CT) extracts in high fat diet (HFD)-induced obese and diabetic mice. C57BL/6N mice were assigned to six groups: normal diet (ND, n=7), HFD (n=10), HFD with 5% ML powder (ML, n=10), HFD with 2% SK powder (SK, n=10), HFD with 5% MF powder (MF, n=10), and HFD with 5% CT powder (CT, n=10). Mice were fed their assigned diet for 14 weeks. ML group showed significant reduction in levels of plasma glucose and insulin compared with the HFD group. Plasma total cholesterol (T-C) was significantly reduced by ML and SK compared with the HFD group. Plasma high-density lipoprotein cholesterol (HDL-C) and HTR (HDL-C to T-C ratio) levels of the ML, SK, MF, and CT groups were significantly elevated compared to the HFD group. Moreover, concentrations of hepatic T-C and triglycerides in the ML, SK, MF, and CT groups were significantly reduced in comparison to the HFD group. Levels of pAKT, pS6K, and pAMPK significantly increased in the ML group compared with the HFD group. Taken together, ML appears to be the most potent anti-diabetic and anti-dyslipidemic substance among sericultural products. ML could be developed as a potential agent for diabetes and its complication management.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.155-157
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• 1993

DNA transfection conditions were investigated by calcium phosphate-DNA co-precipitation in SK-N-BE(2)C human neuroblastoma cells. The DNA plasmid of TH2400CAT was used in which rat tyrosine hydroxylase gene was inserted into chloramphenicol acetyltransferase reporter gent. The transfection efficiency was 25-30% and the method was simple and reproducible. So, the method will be a good tool for transient transfection analysis.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.46-46
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• 2002

Cdk5, a neuronal Cdc2-like kinase, exhibits a variety of functions in neuronal differentiation and neurocytoskeleton dynamics as well as neuronal degeneration and cell death. However, its role in retinoic acid (RA)-induced differentiation has not been reported yet. We newly found that RA treatment of SK-N-BE(2)C, human neuroblastoma, increased expression of Cdk5 concomitantly with a neuronal specific activator, p35.(omitted)

• Journal of Life Science
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• v.21 no.8
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• pp.1190-1198
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• 2011

Extraction methods of medicinal plants were evaluated for growth enhancing effects of human neuroblastoma SK-N-SH cells. Hot-water extraction (reflux for 5 hr), hot-water extraction post treatment (100$^{\circ}C$ or 120$^{\circ}C$, 90 min) and ethanol extraction (reflux for 5 hr) methods were applied to Angelica gigas, Rhemania glutinosa, Paeonia lactiflora and Cnidium officinale samples to extract their constituents. Cells were treated for 2 hr with various concentrations of extracts (0, 0.5, 1, 2, 4 ${\mu}g/{\mu}l}$ media) prior to $H_2O_2$ (250 ${\mu}M$) treatment for 2 hr to provide oxidative stress. Cell viability, caspase-3 expression and apoptosis were measured for cells treated with sample extracts. Hot-water extract exhibited a stronger growth enhancing and apoptosis protecting ability than other extracts. These activities were shown at less than 1 ${\mu}g/{\mu}l}$ concentration, and not greater than 2 ${\mu}g/{\mu}l}$ concentration. Hot-water extract contained more polyphenolic compounds than other extracts coming along with stronger antioxidant activity. The efficacy of antioxidant activity was stronger in the hot-water extract of Angelica gigas than other hot-water extracts of medicinal plants. These results suggest that hot-water extraction is an appropriate method to extract materials for growth enhancing and apoptosis protection of SK-N-SH cells, and hot-water extracts of Angelica gigas might be useful materials for protection from aging brain cells.

• Journal of Life Science
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• v.28 no.11
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• pp.1321-1331
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• 2018

The aim of this study was to separate the photosensitizer that induces apoptosis of U937 and SK-HEP-1 cells from Nostoc commune. Dried N. commune was extracted with $CH_2Cl_2/MeOH$ (1:1) to separate the photosensitizer using various chromatographic techniques. The isolated compound was identified as pheophytin a ($C_{55}H_{74}N_4O_5$) with a molecular weight of 870. Its photodynamic activities were assessed under different irradiation conditions (light and non-light) at the same concentration range of $1.15-23.0{\mu}M$. The apoptosis inducing activity in U937 or SK-HEP-1 cells appeared only in the light. The mechanisms underlying the pheophytin a-mediated photodynamic inhibition of cancer cells were further investigated by examining cell morphology changes, cytotoxicity, caspase-3/7 activity, fluorescence staining, flow cytometry analysis, and DNA fragmentation in these two cell lines. The positive control and the light irradiation group showed typical apoptotic responses, including morphological changes, cytotoxicity, caspase activity, nucleus shrinkage owing to chromatin condensation, DNA laddering, and the presence of apoptotic bodies. Cytotoxicity markedly increased in a dose-dependent manner after a 12 hr exposure. Caspase-3/7 activity was higher in U937 cells than in SK-HEP-1 cells. Apoptosis induction therefore appeared to be both concentration- and light-dependent. In conclusion, pheophytin a, isolated from the blue green alga N. commune, had a photodynamic apoptosis-inducing effect on U937 and SK-HEP-1 cells. The findings reported here can be used as basic data for the development of next-generation photosensitizers from N. commune.

• Archives of Pharmacal Research
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• v.27 no.8
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• pp.834-839
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• 2004

In human neuroblastoma SK-N-BE(2) cells undergoing apoptotic death induced by ginsenos-ide Rh2, a dammarane glycoside that was isolated from Panax ginseng C. A. Meyer, caspase-1 and caspase-3 were activated. The expression of Bax was increased in the cells treated with ginsenoside Rh2, whereas Bcl-2 expression was not altered. Treatment with caspase-1 inhibi-tor, Ac-YVAD-CMK, or caspase-3 inhibitor, Z-DEVD-FMK, partially inhibited ginsenoside Rh2-induced cell death but almost suppressed the cleavage of the 116 kDa PARP into a 85 kDa fragment. When the levels of p53 were examined in this process, p53 accumulated rapidly in the cells treated early with ginsenoside Rh2. These results suggest that activation of caspase-1 and -3 and the up-regulation of Bax are required in order for apoptotic death of SK-N-BE(2) cells to be induced by ginsenoside Rh2, and p53 plays an important role in the pathways to promote apoptosis.