• Journal of Life Science
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• v.24 no.9
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• pp.1012-1018
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• 2014

Sasa quelpaertensis Nakai (Korean name, Jeju-Joritdae) is one of the most abundant plants on Mt. Halla, Jeju Island, and it has long been used in traditional medicines. Recent studies have reported it as possessing various beneficial functions, including anti-inflammatory, anti-diabetic, anti-hypertension, anti-gastritis, anti-oxidant, and anti-cancer effects. However, the molecular mechanisms of its anti-cancer activity have not been clearly elucidated. In this study, we investigated the anti-cancer effects and mechanism of S. quelpaertensis on human colon cancer HT-29 cells. Cell growth inhibition by S. quelpaertensis was determined by MTT assay. Apoptosis was performed by DNA fragmentation, flow cytometry with propidium iodide staining (PI), and reverse transcription-polymerase chain reaction (RT-PCR) to confirm the anti-apoptotic factors, such as inhibitor of apoptosis (IAP) family members. $NO^{\bullet}$ production was determined by Griess assay. S. quelpaertensis treatment resulted in the time- and dose-dependent inhibition of the cell viability of HT-29 cells by inducing apoptosis, as evidenced by the accumulation of the sub-G1 cell population stained by PI, as well as the ladder-like DNA fragmentation in a dose-dependent manner. S. quelpaertensis-inducing apoptosis was accompanied by the induction of S cell cycle arrests, increasing $NO^{\bullet}$ concentrations, and the down-regulation of IAPs, including X-chromosome-linked IAP (XIAP), cellular IAP-1 (cIAP-1), cIAP-2, and survivin. Taken together, these findings have important implications for future clinical developments of S. quelpaertensis in colon cancer treatment.

• Journal of Ginseng Research
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• v.39 no.1
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• pp.46-53
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• 2015

Background: Glucocorticoids (GCs) are commonly used in many chemotherapeutic protocols and play an important role in the normal regulation of bone remodeling. However, the prolonged use of GCs results in osteoporosis, which is partially due to apoptosis of osteoblasts and osteocytes. In this study, effects of Korean Red Ginseng (KRG) on GC-treated murine osteoblastic MC3T3-E1 cells and a GC-induced osteoporosis mouse model were investigated. Methods: MC3T3-E1 cells were exposed to dexamethasone (Dex) with or without KRG and cell viability was measured by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Realtime polymerase chain reaction was performed to evaluate the apoptotic gene expression; osteogenic gene expression and alkaline phosphatase (ALP) activity were also measured. Western blotting was performed to evaluate the mitogen-activated protein kinase (MAPK) proteins. A GC-induced osteoporosis animal model was used for in vivo study. Results and conclusion: The MTT assay revealed that Korean Red Ginseng (KRG) prevents loss of cell viability caused by Dex-induced apoptosis in MC3T3E1 cells. Real-time polymerase chain reaction data showed that groups treated with both Dex and KRG exhibited lower mRNA levels of caspase-3 and -9, whereas the mRNA levels of Bcl2, IAPs, and XIAP increased. Moreover, groups treated with both Dex and KRG demonstrated increased mRNA levels of ALP, RUNX2, and bone morphogenic proteins as well as increased ALP activity in MC3T3-E1 cells, compared to cells treated with Dex only. In addition, KRG increased protein kinase B (AKT) phosphorylation and decreased c-Jun N-terminal kinase (JNK) phosphorylation. Moreover, microcomputed tomography analysis of the femurs showed that GC implantation caused trabecular bone loss. However, a significant reduction of bone loss was observed in the KRG-treated group. These results suggest that the molecular mechanism of KRG in the GC-induced apoptosis may lead to the development of therapeutic strategies to prevent and/or delay osteoporosis.

• Journal of Life Science
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• v.29 no.3
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• pp.318-324
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• 2019

Squamous cell carcinoma is the primary tumor type in head and neck cancers, the fifth most common malignant neoplasm world-wide. Survivin, a member of the inhibitor of apoptosis family, is highly expressed in head and neck carcinoma patients and correlated with more aggressive forms. In this study, we investigated whether YM155, a specific survivin inhibitor, could induce apoptosis in head and neck AMC-HN4 cells. YM155 was found to markedly induce apoptosis and cleavage of PARP, a marker of apoptosis. Furthermore, YM155 promoted apoptosis in other cancer cells, such as glioma (U251MG) and renal carcinoma (Caki) cells. In contrast, YM155 had no effect on apoptosis in normal mesangial cells. YM155 significantly induced caspase activation, and pan caspase inhibitor z-VAD-fmk markedly blocked apoptosis, PARP cleavage, and caspase-3 cleavage. Therefore, YM155 was seen to instigate caspase-dependent apoptosis in head and neck AMC-HN4 cells, inducing downregulation of survivin as well as other apoptotic proteins such as c-FLIP and Mcl-1. In addition, the induction of apoptosis and PARP cleavage by YM155 treatment was effectively inhibited in survivin-, c-FLIP- and Mcl-1-over-expressing head and neck AMC-HN4 cells. In conclusion, YM155 is a potent candidate for inducing cell death in head and neck AMC-HN4 cells.

• Sleep Medicine and Psychophysiology
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• v.20 no.2
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• pp.75-81
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• 2013

Objectives: There are a lot of studies that analyze the interaction between the emotion of disgust and the functional brain images using fMRI and PET. But studies using sLORETA (standardized low resolution brain electromagnetic tomography) almost do not exist. The aim of this research is to explore the relationship of the emotion of disgust and the cortical activation using sLORETA analysis. Methods: Forty five healthy young adults ($27.1{\pm}2.6$ years) participated in the study. While they were watching 4 neutral images and 4 disgusting images associated with mutilation selected from the international affective picture system (IAPS), participants' EEGs were taken for 30 seconds per one picture. Through these obtained EEG data, sLORETA analysis was performed to compare EEGs associated with neutral and negative images. Results: During looking for visual disgusting stimulus, all participants reported unpleasantness, arousal and stress. In sLORETA analysis, the decrease of current density in theta wave was shown at left frontal superior gyrus (BA10) and middle gyrus (BA10, 11). This voxel cluster consists of a total of 11 voxels and the threshold of t value indicating statistically significant decreases in the current density (p<0.05) was -1.984. There were no differences between male and female in the degree of being disgusted by the stimuli. Conclusion: This finding may suggest that the activation of dorsolateral prefrontal cortex might be associated with regulating disgust emotion.

• Journal of Life Science
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• v.29 no.4
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• pp.410-420
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• 2019

Citrus unshiu peel extracts possess a variety of beneficial effects, and studies on their anticancer activity have been reported. However, the exact mechanisms underlying this activity remain unclear. In the current study, the apoptotic effect of ethanol extract of C. unshiu peel (EECU) on human breast adenocarcinoma MDA-MB-231 cells and related mechanisms were investigated. The results showed that the survival rate of MDA-MB-231 cells treated with EECU was significantly inhibited in a concentration-dependent manner, which was associated with the induction of apoptosis. EECU-induced apoptosis was associated with the activation of caspase-8 and caspase-9, which initiate extrinsic and intrinsic apoptosis pathways, respectively, and caspase-3, a representative effect caspase. EECU suppressed the expression of the inhibitor of apoptosis family of proteins, leading to an increased Bax/Bcl-2 ratio and proteolytic degradation of poly (ADP-ribose) polymerase. EECU also enhanced the loss of the mitochondrial membrane potential and cytochrome c release from the mitochondria to the cytosol, along with truncation of Bid. In addition, EECU activated AMP-activated protein kinase (AMPK), and compound C, an AMPK inhibitor, significantly weakened EECU-induced apoptosis and cell viability reduction. Furthermore, EECU promoted the generation of reactive oxygen species (ROS), which acted as upstream signals for AMPK activation as pretreatment of cells, with the antioxidant N-acetyl cysteine reversing both EECU-induced AMPK activation and apoptosis. Collectively, these findings suggest that EECU inhibits MDA-MB-231 adenocarcinoma cell proliferation by activating intrinsic and extrinsic apoptotic pathways, which was mediated through ROS/AMPK-dependent pathways.