• Proceedings of the PSK Conference
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• 2002.10a
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• pp.319.1-319.1
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• 2002

Yomogin. an eudesmane sesquiterpene isolated from Artemisia princeps, was found to induce apoptosis in human promyelocytic leukaemia, HL -60 cell with characteristic apoptotic features like nuclear condensation, apoptotic body formation, flipping of membrane phosphatidylserine, release of mitochondrial cytochrome c and caspase-8. -9. and -3 activation. Furthermore. early yomogin-induced cytochrome c release was not affected by the caspase inhibitor Z-VAd fmk and preceded loss of mitochondrial membrane potential. The results suggest that induction of apoptosis by yomogin may provide a pivotal mechanism for their cancer chemopreventive function.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.63.2-63.2
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• 2008

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.159.3-160
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• 2002

• Molecules and Cells
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• v.38 no.12
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• pp.1054-1063
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• 2015

Mitochondria play a crucial role in eukaryotic cells; the mitochondrial electron transport chain (ETC) generates adenosine triphosphate (ATP), which serves as an energy source for numerous critical cellular activities. However, the ETC also generates deleterious reactive oxygen species (ROS) as a natural byproduct of oxidative phosphorylation. ROS are considered the major cause of aging because they damage proteins, lipids, and DNA by oxidation. We analyzed the chronological life span, growth phenotype, mitochondrial membrane potential (MMP), and intracellular ATP and mitochondrial superoxide levels of 33 single ETC component-deleted strains during the chronological aging process. Among the ETC mutant strains, 14 ($sdh1{\Delta}$, $sdh2{\Delta}$, $sdh4{\Delta}$, $cor1{\Delta}$, $cyt1{\Delta}$, $qcr7{\Delta}$, $qcr8{\Delta}$, $rip1{\Delta}$, $cox6{\Delta}$, $cox7{\Delta}$, $cox9{\Delta}$, $atp4{\Delta}$, $atp7{\Delta}$, and $atp17{\Delta}$) showed a significantly shorter life span. The deleted genes encode important elements of the ETC components succinate dehydrogenase (complex II) and cytochrome c oxidase (complex IV), and some of the deletions lead to structural instability of the membrane-$F_1F_0$-ATP synthase due to mutations in the stator stalk (complex V). These short-lived strains generated higher superoxide levels and produced lower ATP levels without alteration of MMP. In summary, ETC mutations decreased the life span of yeast due to impaired mitochondrial efficiency.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5895-5900
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• 2013

Dictamnine (Dic) has the ability to exert cytotoxicity in human cervix, colon, and oral carcinoma cells and dihydroartemisinin (DHA) also has potent anticancer activity on various tumour cell lines. This report explores the molecular mechanisms by which Dic treatment and combination treatment with DHA and Dic cause apoptosis in human lung adenocarcinoma A549 cells. Dic treatment induced concentration- and time-dependent cell death. FCM analysis showed that Dic induced S phase cell cycle arrest at low concentration and cell apoptosis at high concentration in which loss of mitochondrial membrane potential (${\Delta}{\Psi}m$) was not involved. In addition, inhibition of caspase-3 using the specific inhibitor, z-DQMD-fmk, did not attenuate Dic-induced apoptosis, implying that Dic-induced caspase-3-independent apoptosis. Combination treatment with DHA and Dic dramatically increased the apoptotic cell death compared to Dic alone. Interestingly, pretreatment with z-DQMD-fmk significantly attenuated DHA and Dic co-induced apoptosis, implying that caspase-3 plays an important role in Dic and DHA co-induced cell apoptosis. Collectively, we found that Dic induced S phase cell cycle arrest at low concentration and cell apoptosis at high concentration in which mitochondria and caspase were not involved and DHA enhanced Dic induced A549 cell apoptosis via a caspase-dependent pathway.

• Korean Journal of Pharmacognosy
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• v.52 no.3
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• pp.149-156
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• 2021

Excessive glutamate can cause oxidative stress in neuronal cells and this can be the reason for neurodegenerative disease. In this study, we investigated the protective effect of Spirulina maxima hot ethanol extract on mouse hippocampal HT22 cell of which glutamate receptor has no function. HT22 cells were pre-treated with S. maxima sample at a dose dependent manner (1, 10 and 100 ㎍/ml). After an hour, glutamate was treated. Cell viability, reactive oxygen species (ROS) accumulation, Ca²⁺ influx, decrease of mitochondrial membrane potential level and glutathione related assays were followed by then. S. maxima ethanol extract improved the cell viability by suppressing the ROS and Ca²⁺ formation, retaining the mitochondrial membrane potential level and protecting the activity of the antioxidant enzymes compared with group of vehicle-treated controls. These suggest that S. maxima may decelerate the neurodegeneration by attenuating neuronal damage and oxidative stress.

• Herbal Formula Science
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• v.30 no.2
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• pp.59-66
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• 2022

Objectives : This study is to investigate whether Carthami flos exhibits a synergistic effect on the apoptotic effect of doxorubicin on human gastric cancer cells. Methods : We used AGS, a human gastric cancer cell line. To investigate the apoptotic efficacy of doxorubicin and Carthami flos, MTT and CCK-8 methods were used. To confirm apoptosis, cell cycle and mitochondrial membrane potential changes were confirmed. To investigate the mechanism of apoptosis, the reactive oxygen species (ROS) experiment was performed. Results : 1. Doxorubicin or Carthami flos induced cell death in the human gastric cancer cell line AGS. 2. Carthami flos showed a synergistic effect of cell death by doxorubicin. 3. The cell cycle and mitochondrial membrane potential changes revealed that cell death was apoptosis. 4. Apoptosis was related to reactive oxygen species (ROS) generation. Conclusions : This result shows the anticancer synergistic effect of Carthami flos in gastric cancer cells, and is considered to be an important basis for the development of anticancer drugs for Carthami flos.

• Biomolecules & Therapeutics
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• v.10 no.3
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• pp.152-158
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• 2002

The present study elucidated the effect of $\beta$-carbolines (harmaline and harmalol) on brain mitochondlial dysfunction caused by the tyrosinase-induced oxidation of dopamine. Harmaline, harmalol and antioxidant enzymes (SOD and catalase) attenuated the dopamine-induced alteration of membrane potential, cytochrome c release and thiol oxidation in mitochondria. In contrast, antioxidant enzymes failed to reverse mitochondrial dysfunction induced by dopmnine plus tyrosinase. $\beta$-Carbolines decreased the damaging effect of dopamine plus tyrosinase against mitochondria, except no effect of harmalol on thiol oxidation. Antioxidant enzymes decreased the melanin formation from dopamine in the reaction mixture containing mitochondria but did not reduce the formation of dopamine quinone caused by tyrosinase. Both harmalol and harmaline inhibited the formation of reactive quinone and melanin. Harmalol being more effective for quinone formation and vise versa. The results indicate that compared to MAO-induced dopamine oxidation, the toxic effect of dopamine in the presence of tyrosinase against mitochondria may be accomplished by the dopamine quinone and toxic substances other than reactive oxygen species. $\beta$-Carbolines may decrease the dopamine plus tyrosinase-induced brain mitochondrial dysfunction by inhibition of the formation of reactive quinone and the change in membrane permeability.

• Molecules and Cells
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• v.46 no.4
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• pp.219-230
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• 2023

Down syndrome (DS) is the most common autosomal aneuploidy caused by trisomy of chromosome 21. Previous studies demonstrated that DS affected mitochondrial functions, which may be associated with the abnormal development of the nervous system in patients with DS. Runt-related transcription factor 1 (RUNX1) is an encoding gene located on chromosome 21. It has been reported that RUNX1 may affect cell apoptosis via the mitochondrial pathway. The present study investigated whether RUNX1 plays a critical role in mitochondrial dysfunction in DS and explored the mechanism by which RUNX1 affects mitochondrial functions. Expression of RUNX1 was detected in induced pluripotent stem cells of patients with DS (DS-iPSCs) and normal iPSCs (N-iPSCs), and the mitochondrial functions were investigated in the current study. Subsequently, RUNX1 was overexpressed in N-iPSCs and inhibited in DS-iPSCs. The mitochondrial functions were investigated thoroughly, including reactive oxygen species levels, mitochondrial membrane potential, ATP content, and lysosomal activity. Finally, RNA-sequencing was used to explore the global expression pattern. It was observed that the expression levels of RUNX1 in DS-iPSCs were significantly higher than those in normal controls. Impaired mitochondrial functions were observed in DS-iPSCs. Of note, overexpression of RUNX1 in N-iPSCs resulted in mitochondrial dysfunction, while inhibition of RUNX1 expression could improve the mitochondrial function in DS-iPSCs. Global gene expression analysis indicated that overexpression of RUNX1 may promote the induction of apoptosis in DS-iPSCs by activating the PI3K/Akt signaling pathway. The present findings indicate that abnormal expression of RUNX1 may play a critical role in mitochondrial dysfunction in DS-iPSCs.

• Animal cells and systems
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• v.15 no.4
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• pp.287-294
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• 2011

The accelerated cooling rate associated with vitrification reduces injuries attributed to cryopreservation and improves the post-freezing developmental competence of vitrified embryos. In this study, embryos were vitrified and warmed and morphologically evaluated for their development to blastocysts. Survival rates between the fresh ($96.7%{\pm}3.8%$) and vitrified embryos ($90.7%{\pm}5.1%$) did not differ significantly (P>0.05). The mitochondrial membrane potential of fresh control cells measured by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl carbocyanide iodide staining was similar to that of cryoprotected and vitrified embryos. Mitochondrial staining with rhodamine 123 did not differ among the fresh, cryoprotected, and vitrified embryos. Moreover, the distribution of $H_2O_2$, assessed by 2',7'-dichlorodihydrofluorescein diacetate staining, did not differ among the groups. The results showed that the developmental rate did not differ significantly among the fresh ($87.8%{\pm}11.3%$), cryoprotected ($83.2%{\pm}7.6%$), and vitrified 2-cell embryos ($75.8%{\pm}14.2%$). The mean number of the inner cell mass (ICM), trophectoderm (TE), and apoptotic cells was counted and statistically compared, and although the number of ICM and TE was decreased in the cryoprotected and vitrified embryos, there were no significant differences among the groups (P>0.05). During the cultivation period, randomly selected blastocysts from each group were stained using either 4',6-diamidino-2-phenylindole and bisbenzimide or the terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling technique. The incidence of apoptosis appeared to be almost identical in all the groups. Droplet vitrification could subsequently lead to high survival and developmental rates of cryopreserved mouse embryos.