• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.313-319
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• 2009

To improve the growth of human mesenchymal stem cells(hMSCs) under general cell culture conditions(20% $O_2$ and 5% $CO_2$), we examined the effect of s-allylcysteine(SAC), which is known as an antioxidant and the main component of aged-garlic extract, on hydrogen peroxide-induced cellular stress in hMSCs. We found that SAC blocked hydrogen peroxideinduced cell death and cellular apoptosis, but that SAC did not improve the growth of hMSCs during short-term culture. To evaluate the protective effect of SAC, we examined the endogenous expression of the antioxidant enzymes catalase (CAT), superoxide dismutase(SOD), and glutathione peroxidase(Gpx) in hMSCs. Hydrogen peroxide was found to downregulate the expression of CAT, SOD, and Gpx at the protein level. However, in the pre-treatment group of SAC, SAC inhibited the hydrogen peroxide-induced down-regulation of CAT, SOD, and Gpx. Unfortunately, treatment with SAC alone did not induce the up-regulation of antioxidant enzymes and the cell proliferation of hMSCs. Surprisingly, SAC improved cell growth in a single cell level culture of hMSCs. These results indicate that SAC may be involved in the preservation of the self-renewal capacity of hMSCs. Taken together, SAC improves the proliferation of hMSCs via inhibition of oxidative-stress-induced cell apoptosis through regulation of antioxidant enzymes. In conclusion, SAC may be an indispensable component in an in vitro culture system of human MSCs for maintaining self-renewal and multipotent characterization of human MSCs.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.6
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• pp.1594-1598
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• 2005

Scopoletin (6-methoxy-7-hydrorycournarin) is a phenolic coumarin and a member of the phytoalexins. In this study we investigated whether scopoletin causes apoptosis in human hepatoma HepG2 cells and, if so, by what mechanisms. We report that scopoletin induced apoptosis as confirmed by a chromatin condensation. The signal cascade acivated by scopoletin included the activation of caspase-3 as evidenced by increased pretense activity. Activation of caspase-3 resulted in the cleavage of 116 kDa poly(ADP-ribose) polymerase (PARP) to 85 kDa cleavage product in a dose-dependent fashion. Also, scopoletin-induced apoptotic mechanism of HepG2 cells involved the generation of hydrogen peroxide. Taken together, these results suggest that scopgletin induces hydrogen peroxide generation, which, in turn, causes activation of caspase-3, degradation of PARP, and eventually leads to apoptotic cell death in HepG2 cells.

• Journal of Applied Biological Chemistry
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• v.63 no.3
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• pp.283-290
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• 2020

Oxidative stress is one of the contributors of neurodegenerative disorders including Alzheimer's disease. According to previous studies, Aster yomena (Kitam.) Honda (AY) possesses variable pharmacological activities including anti-coagulant and anti-obesity effect. In this study, we aimed to determine the neuroprotective effect of ethyl acetate fraction from Aster yomena (Kitam.) Honda (EFAY) against oxidative stress. Therefore, we carried out 3-(4,5-dimethylthiazol-2-yl)-2,3-diphenyl tetrazolium bromide, lactate dehydrogenase (LDH), and 2',7'-dichlorofluorescin diacetate assays in SH-SY5Y neuronal cells treated with hydrogen peroxide (H₂O₂). H₂O₂-treated control cells exhibited reduced viability of cells, and increased LDH release and reactive oxygen species (ROS) production compared to normal cells. However, treatment with EFAY restored the cell viability and inhibited LDH release and ROS production. To investigate the underlying mechanisms by which EFAY attenuated neuronal oxidative damage, we measured protein expressions using Western blot analysis. Consequently, it was observed that EFAY down-regulated cyclooxygenase-2 and interleukin-1β protein expressions in H₂O₂-treated SH-SY5Y cells that mediated inflammatory reaction. In addition, apoptosis-related proteins including B-cell lymphoma-2-associated X protein/B-cell lymphoma-2 ratio, cleaved caspase-9, and cleaved-poly (ADP-ribose) polymerase protein expressions were suppressed when H₂O₂-treated cells were exposed to EFAY. Our results indicate that EFAY ameliorated H₂O₂-induced neuronal damage by regulating inflammation and apoptosis. Altogether, AY could be potential therapeutic agent for neurodegenerative diseases.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.1
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• pp.63-68
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• 2005

Hydrogen peroxide ($H_2O_2$) causes oxidative stress and is considered as an inducer of cell death in various tissues. Two-pore domain $K^+$ ($K_{2p}$) channels may mediate $K^+$ efflux during apoptotic volume decreases (AVD) in zygotes and in mouse embryos. In the present study, we sought to elucidate linkage between $K_{2p}$ channels and cell death by $H_2O_2$. Thus $K_{2p}$ channels (TASK-1, TASK-3, TREK-1, TREK-2) were stably transfected in HEK-293 cells, and cytotoxicity assay was preformed using cell counting kit-8 (CCK-8). Cell survival rates were calculated using the cytotoxicity assay data and dose-response curve was fitted to the $H_2O_2$ concentration. Ionic currents were recorded in cell-attached mode. The bath solution was the normal Ringer solution and the pipette solution was high $K^+$ solution. In HEK-293 cells expressing TREK-1, TREK-2, TASK-3, $H_2O_2$ induced cell death did not change in comparison to non-transfected HEK-293. In HEK-293 cells expressing TASK-1, however, dose-response curve was significantly shifted to the left. It means that $H_2O_2$ induced cell death was increased. In cell attached-mode recording, application of $H_2O_2$ (300μM) increased activity of all $K_{2p}$ channels. However, a low concentration of $H_2O_2$ ($50{\mu}M$) increased only TASK-1 channel activity. These results indicate that TASK-1 might participate in $K^+$ efflux by $H_2O_2$ at low concentration, thereby inducing AVD.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.111-111
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• 2001

• Journal of Microbiology and Biotechnology
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• v.29 no.8
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• pp.1193-1203
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• 2019

We investigated the protective effects of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) from Polysiphonia morrowii Harvey against hydrogen peroxide ($H_2O_2$)-induced apoptosis in Vero cells. BDB exhibited scavenging activity for DPPH, hydroxyl, and alkyl radicals. BDB also inhibited $H_2O_2$-induced lipid peroxidation, cell death, and apoptosis in Vero cells by inhibiting the production of ROS. To evaluate the molecular mechanisms of apoptosis inhibition, the expression of Bax/Bcl-xL and $NF-{\kappa}B$ was assessed by western blot assay. BDB significantly suppressed the cleavage of caspase-9 and PARP and reduced Bax levels in $H_2O_2$-induced Vero cells. Besides, BDB suppressed the phosphorylation of $NF-{\kappa}$B and the translocation of p65 in $H_2O_2$-induced cells. Furthermore, we evaluated the effect of BDB on ROS production, cell death, and lipid peroxidation in an $H_2O_2$-stimulated zebrafish embryo model. Taken together, these results indicated that ROS generation and cell death were significantly inhibited by BDB in zebrafish embryos, thereby proving that BDB exerts excellent antioxidant activity in vitro and in vivo.

• Microbiology and Biotechnology Letters
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• v.49 no.2
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• pp.138-147
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• 2021

The overproduction of reactive nitrogen species (RNS) and reactive oxygen species (ROS) causes oxidative damage to neuronal cells, leading to the progression of neurodegenerative diseases. In this study, we determined the nitric oxide radical (NO), hydroxyl radical (·OH), and superoxide anion radical (O₂^-) scavenging activities of apigenin. Our results showed that apigenin exhibited remarkable, concentration-dependent ·OH, O₂^-, and NO radical scavenging activities. Particularly, apigenin indicated the strongest ·OH radical scavenging activity with 93.38% in the concentration of 100 µM. Furthermore, we also investigated the protective effects of apigenin against hydrogen peroxide (H₂O₂)-induced oxidative stress in SH-SY5Y cells. The H₂O₂ treatment resulted in a significant decrease in cell viability, as well as an increase in lactate dehydrogenase (LDH) release and ROS production compared with the H₂O₂-nontreated SH-SY5Y cells. However, the cell viability significantly increased in the apigenin-treated group, as well as inhibited ROS generation and LDH release compared with the H₂O₂-induced control group. To elucidate the protective mechanisms of apigenin against oxidative stress in SH-SY5Y, we analyzed the apoptosis-related protein expression. The apigenin treatment resulted in the downregulated expression of apoptosis-related protein markers, such as cytochrome C, cleaved caspase-3, poly (ADP)-ribose polymerase (PARP), and B-cell lymphoma 2-associated X (Bax), as well as the upregulated expression of anti-apoptosis markers such as B-cell lymphoma 2 (Bcl-2). In this study, we report that apigenin exhibits a neuroprotective effect against oxidative stress in SH-SY5Y cells. These results suggest that apigenin may be considered as a potential agent for neurodegenerative disease prevention.

• Nutrition Research and Practice
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• v.12 no.2
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• pp.93-100
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• 2018

BACKGROUND/OBJECTIVE: Oxidative stress plays a key role in neuronal cell damage, which is associated with neurodegenerative disease. The aim of present study was to investigate the neuroprotective effects of perilla oil (PO) and its active component, alpha-linolenic acid (ALA), against hydrogen peroxide $(H_2O_2)$-induced oxidative stress in SH-SY5Y neuronal cells. MATERIALS/METHODS: The SH-SY5Y human neuroblastoma cells exposed to $250{\mu}M$ $H_2O_2$ for 24 h were treated with different concentrations of PO (25, 125, 250 and $500{\mu}g/mL$) and its major fatty acid, ALA (1, 2.5, 5 and $25{\mu}g/mL$). We examined the effects of PO and ALA on $H_2O_2$-induced cell viability, lactate dehydrogenase (LDH) release, and nuclear condensation. Moreover, we determined whether PO and ALA regulated the apoptosis-related protein expressions, such as cleaved-poly ADP ribose polymerase (PARP), cleaved caspase-9 and -3, BCL-2 and BAX. RESULTS: Treatment of $H_2O_2$ resulted in decreased cell viability, increased LDH release, and increase in the nuclei condensation as indicated by Hoechst 33342 staining. However, PO and ALA treatment significantly attenuated the neuronal cell death, indicating that PO and ALA potently blocked the $H_2O_2$-induced neuronal apoptosis. Furthermore, cleaved-PARP, cleaved caspase-9 and -3 activations were significantly decreased in the presence of PO and ALA, and the $H_2O_2$-induced up-regulated BAX/BCL-2 ratio was blocked after treatment with PO and ALA. CONCLUSIONS: PO and its main fatty acid, ALA, exerted the protective activity from neuronal oxidative stress induced by $H_2O_2$. They regulated apoptotic pathway in neuronal cell death by alleviation of BAX/BCL-2 ratio, and down-regulation of cleaved-PARP and cleaved caspase-9 and -3. Although further studies are required to verify the protective mechanisms of PO and ALA from neuronal damage, PO and ALA are the promising agent against oxidative stress-induced apoptotic neuronal cell death.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.242-247
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• 2012

Chondrocyte apoptosis has been recognized as an important factor in the pathogenesis of osteoarthritis (OA). Hydrogen peroxide ($H_2O_2$), which produces reactive oxygen species, reportedly induces apoptosis in chondrocytes. The ginsenoside $Rb_1$ (G-$Rb_1$) is the principal component in ginseng and has been shown to have a variety of biological activities, such as anti-arthritis, anti-inflammation, and anti-tumor activities. In this study, we evaluated the effects of G-$Rb_1$ on the mitochondrial permeability transition (MPT) and caspase-3 activity of chondrocyte apoptosis induced by $H_2O_2$. Cultured rat articular chondrocytes were exposed to $H_2O_2$ with or without G-$Rb_1$ and assessed for viability, MPT, Bcl-xL/Bax expression, caspase-3 activity, and apoptosis. The co-treatment with G-$Rb_1$ showed an inhibition of MPT, caspase-3 activity, and cell death. Additionally, the levels of the apoptotic protein Bax were significantly lower and the levels of the anti-apoptotic protein Bcl-xL were higher compared with $H_2O_2$ treatment alone. The results of this study demonstrate that G-$Rb_1$ protects chondrocytes against $H_2O_2$-induced apoptosis, at least in part via the inhibition of MPT and caspase-3 activity. These results demonstrate that G-$Rb_1$ is a potentially useful drug for the treatment of OA patients.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.69-79
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• 2020

Aging is one of the risk factors for the development of cardiovascular diseases. During the progression of cellular senescence, cells enter a state of irreversible growth arrest and display resistance to apoptosis. As a flavonoid, quercetin induces apoptosis in various cells. Accordingly, we investigated the relationship between quercetin-induced apoptosis and the inhibition of cellular senescence, and determined the mechanism of oxidative stress-induced vascular smooth muscle cell (VSMC) senescence. In cultured VSMCs, hydrogen peroxide (H₂O₂) dose-dependently induced senescence, which was associated with increased numbers of senescence-associated β-galactosidase-positive cells, decreased expression of SMP30, and activation of p53-p21 and p16 pathways. Along with senescence, expression of the anti-apoptotic protein Bcl-2 was observed to increase and the levels of proteins related to the apoptosis pathway were observed to decrease. Quercetin induced apoptosis through the activation of AMP-activated protein kinase. This action led to the alleviation of oxidative stress-induced VSMC senescence. Furthermore, the inhibition of AMPK activation with compound C and siRNA inhibited apoptosis and aggravated VSMC senescence by reversing p53-p21 and p16 pathways. These results suggest that senescent VSMCs are resistant to apoptosis and quercetin-induced apoptosis attenuated the oxidative stress-induced senescence through activation of AMPK. Therefore, induction of apoptosis by polyphenols such as quercetin may be worthy of attention for its anti-aging effects.