• 대한통합의학회지
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• 제12권1호
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• pp.1-10
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• 2024

Purpose: Lycopene is abundantly contained in Tomatoes and is known for diverse biological activities such as antioxidant, anti-inflammatory, and anticancer effects. In this study, the antioxidative potential of lycopene was investigated through the induction of hemeoxygenase (HO)-1 by nuclear factor-erythroid 2 p45-related factor2 (Nrf2) and upstream signaling molecules, mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Aktin RAW 264.7 cells. Methods: The antioxidative potential of lycopene against oxidative stress and its molecular mechanisms were determined by the cell viability assay, intracellular reactive oxygen species (ROS) formation assay, and Western blot analysis in RAW 264.7 cells. Results: Lycopene treatment significantly attenuated tert-butyl hydroperoxide (t-BHP) induced intracellular ROS formation in a dose-dependent manner without any cytotoxicity. In addition, 50 µM of lycopene for 6 h treatment induced potent HO-1 expression and its transcription factor, Nrf2. MAPK and PI3K/Aktwere also analyzed due to their critical roles in the regulation of cellular redox homeostasis against oxidative damage. As a result, phosphorylation of extracellular regulated kinase (ERK) was significantly induced by lycopene treatment while the activated status of c-Jun NH2-terminal kinase (JNK), p38, and Akt, were not given any effect. To confirm the antioxidative mechanism of HO-1 mediated by ERK activation, each selective inhibitor was employed in a protection assay, in which oxidative damage occurred by t-BHP. Lycopene, SnPP, and CoPP treatments reflected accelerated HO-1 expression could be a protective role against oxidative damage-initiated cell death. A selective inhibitor for ERK significantly inhibited the lycopene-induced cytoprotective effect but selective inhibitors for other signaling molecules did not attenuate the rate of t-BHP-induced cell death. Conclusion: In conclusion, lycopene potently scavenged intracellular ROS formation and enhanced the HO-1 mediated antioxidative potential through the modulation of Nrf2, MAPK signaling pathway in RAW 264.7 cells.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.31-31
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• 2022

Plant-derived antioxidants are used as a healthy diet and are known to inhibit various human diseases. In this study, we investigated free radical scavenging and antioxidant activity of extracts from three plants (Ammannia multiflora, Ammannia coccinea and Salix gracilistyla) with the most DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity from 196 plant extracts inhabiting along Nakdong River in Republic of Korea. The three extracts also have strong total antioxidant activity. Moreover, the extracts inhibited hydrogen peroxide (H₂O₂)-induced reactive oxygen species production and depolarized mitochondrial membrane potential in RAW264.7 macrophages. In zebrafish larvae, 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescent intensity, induced by H₂O₂, was markedly reduced by the extracts of A. multiflora, A. coccinea and S. gracilistyla. Meanwhile, the extracts were upregulated Nrf2 and HO-1 expression, and an HO-1 inhibitor reversed the extract-induced oxidative responses both in vivo and in vitro. The data suggest that the extracts of A. multiflora, A. coccinea, and S. gracilistyla exert potential free radical scavenging and antioxidant capacities both in vivo and in vitro by activating the Nrf2/HO-1 signaling pathway.

• 대한한의학방제학회지
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• 제16권2호
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• pp.193-204
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• 2008

Dehydrocostus lactone (DHL) and Mokko lactone (ML) were isolated from Saussureae Radix, and their effects on heme oxygenase-1 (HO-1) expression and hepatoprotection in the liver cell line HepG2 were investigated. DHL induced HO-1 expression and HO activity in a dose-dependent manner, whereas ML lacking one double bond property at 11 and 13 carbons on its own chemical structure had no apparent effects. DHL also induced Nrf2 nuclear translocation and enhanced antioxidant response element (ARE) activation which mediated HO-1 gene transcription. Pretreatment with DHL protected HepG2 cells against oxidative damages caused by H2O2. Interestingly, the hepatoprotective effects of DHL appeared to be associated with HO enzymatic activation, HO-1 expression and Nrf2 activation, because blockage of HO activity by a HO inhibitor and inhibition of HO-1 and Nrf2 cellular synthesis by small interfering RNA abolished heptoprotection afforded by DHL. Taken together, this investigation provides evidence supporting that Saussureae Radix is hepatoprotective against oxidative stress that causes abnormal liver damages.

• Biomolecules & Therapeutics
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• 제32권1호
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• pp.84-93
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• 2024

Rosmarinic acid (RA) is a phenolic ester that protects human keratinocytes against oxidative damage induced by ultraviolet B (UVB) exposure, however, the mechanisms underlying its effects remain unclear. This study aimed to elucidate the cell signaling mechanisms that regulate the antioxidant activity of RA and confirm its cyto-protective role. To explore the signaling mechanisms, we used the human keratinocyte cell line HaCaT and SKH1 hairless mouse skin. RA enhanced glutamate-cysteine ligase catalytic subunit (GCLC) and glutathione synthetase (GSS) expression in HaCaT cells in a dose- and time-dependent manner. Moreover, RA induced nuclear factor erythroid-2-related factor 2 (NRF2) nuclear translocation and activated the signaling kinases protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Treatment with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002, the ERK inhibitor U0126, and small interfering RNA (siRNA) gene silencing suppressed RA-enhanced GCLC, GSS, and NRF2 expression, respectively. Cell viability tests showed that RA significantly prevented UVB-induced cell viability decrease, whereas the glutathione (GSH) inhibitors buthionine sulfoximine, LY294002, and U0126 significantly reduced this effect. Moreover, RA protected against DNA damage and protein carbonylation, lipid peroxidation, and apoptosis caused by UVB-induced oxidative stress in a concentration-dependent manner in SKH1 hairless mouse skin tissues. These results suggest that RA protects against UVB-induced oxidative damage by activating AKT and ERK signaling to regulate NRF2 signaling and enhance GSH biosynthesis. Thus, RA treatment may be a promising approach to protect the skin from UVB-induced oxidative damage.

• Biomolecules & Therapeutics
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• 제27권4호
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• pp.381-385
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• 2019

We attempted to examine anti-inflammatory and anti-oxidant effects of 4'-O-${\beta}$-D-glucosyl-5-O-methylvisamminol (GOMV), the first epigenetic inhibitor of histone phosphorylation at Ser10. While GOMV did not affect the viability of murine macrophage RAW 264.7 cells, it significantly suppressed lipopolysaccharide (LPS)-induced generation of prostaglandin $E_2$ ($PGE_2$) and nitric oxide (NO) through transcriptional inhibition of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). GOMV also scavenged free radicals in vitro, increased NF-E2-related factor 2 (NRF2), and activated antioxidant response element (ARE), thereby resulting in the induction of phase II cytoprotective enzymes in human keratinocyte HaCaT cells. Finally, GOMV significantly protected HaCaT cells against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced oxidative intracellular damages. Together, our results illustrate that GOMV possesses anti-inflammatory and anti-oxidant activity.

• 생약학회지
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• 제44권4호
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• pp.379-383
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• 2013

Portulaca oleracea L. is known to have many biological benefits such as anti-oxidant, anti-inflammatory, anti-allergic and anti-tumor. The objective of this study is to explore the neuroprotective effect of P. oleracea L. against glutamate-induced oxidative stress in mouse hippocampal HT22 cells. P. oleracea L. 70% ethanol extract and solvent fractions have the potent neroprotective effects on glutamate-induced nerotoxicity by induced the expression of heme oxygenase (HO)-1 in HT22 cells. Especially, ethyl acetate fraction showed higher protective effect. In HT22 cell, P. oleracea L. treatment with ERK inhibitor (PD98059) and c-JUN N-terminal kinase (JNK) inhibitor (SP600125) reduced P. oleracea L. ethyl acetate fraction induced HO-1 expression and P. oleracea L. ethyl acetate fraction also increased ERK and JNK phosphorylation. Furthermore, we found that treatment of P. oleracea L. caused the nuclear accumulation of Nrf2. In conclusion, the ethyl acetate fraction of 70% ethanol extract of P. oleracea L. significantly protect glutamate-induced oxidative damage by induction of HO-1 via Nrf2, ERK and JNK pathway in mouse hippocampal HT22. Taken together these finding suggest that P. oleracea L. ethyl acetate fraction is good source for taking active compounds and may be a potential therapeutic agent for brain disorder that induced by oxidative stress and neuronal damage.

• Journal of Ginseng Research
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• 제47권4호
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• pp.561-571
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• 2023

Background: Escalating evidence shows that ginseng possesses an antiaging potential with cognitive enhancing activity. As mountain cultivated ginseng (MCG) is cultivated without agricultural chemicals, MCG has emerged as a popular herb medicine. However, little is known about the MCG-mediated pharmacological mechanism on brain aging. Methods: As we demonstrated that glutathione peroxidase (GPx) is important for enhancing memory function in the animal model of aging, we investigated the role of MCG as a GPx inducer using GPx-1 (a major type of GPx) knockout (KO) mice. We assessed whether MCG modulates redox and cholinergic parameters, and memory function in aged GPx-1 knockout KOmice. Results: Redox burden of aged GPx-1 KO mice was more evident than that of aged wild-type (WT) mice. Alteration of Nrf2 DNA binding activity appeared to be more evident than that of NFκB DNA binding activity in aged GPx-1 KO mice. Alteration in choline acetyltransferase (ChAT) activity was more evident than that in acetylcholine esterase activity. MCG significantly attenuated reductions in Nrf2 system and ChAT level. MCG significantly enhanced the co-localization of Nrf2-immunoreactivity and ChAT-immunoreactivity in the same cell population. Nrf2 inhibitor brusatol significantly counteracted MCG-mediated up-regulation in ChAT level and ChAT inhibition (by k252a) significantly reduced ERK phosphorylation by MCG, suggesting that MCG might require signal cascade of Nrf2/ChAT/ERK to enhance cognition. Conclusion: GPx-1 depletion might be a prerequisite for cognitive impairment in aged animals. MCG-mediated cognition enhancement might be associated with the activations of Nrf2, ChAT, and ERK signaling cascade.

• Tuberculosis and Respiratory Diseases
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• 제62권1호
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• pp.33-42
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• 2007

연구배경: 다양한 고형암에서 HO-1의 높은 발현이 알려져 있고, 그것의 항산화와 항세포고사의 역할로 인해 빠른 암종의 성장에 중요한 역할이 있음이 보고되고 있다. 대표적인 활성산소종 생성 항암제인 Cisplatin은 현재까지 폐암치료에 가장 광범위하게 사용되고 있으나, 여러 내성발생이 임상치료의 주요문제로 대두되고 있다. 저자들은 A549 폐암세포주에서 HO-1의 발현이 증가되었고 HO-1 활성억제제나 siRNA 방법을 통해 생존율의 의미 있는 감소와 세포고사가 유도됨을 보고한 바 있다. 이 연구의 목적은 A549 폐암세포주에 cisplatin 처리시 HO-1의 발현의 증가유무와 기전을 규명하고 실제 HO-1의 억제가 cisplatin에 의한 항암제 감수성을 증가시키는지를 알아보는데 있다. 방 법: 비소세포폐암세포주인 A549, NCI-H23, NCIH157, NCI-H460을 이용하였다. 세포독성은 MTT 방법으로 구하였고, HO-1, Nrf2, MAPK의 발현은 Western blotting으로 확인하였다. 또한 MAPK억제제들을 전처치한 후 cisplatin에 의해 유도된 Nrf2와 HO-1의 발현에 미치는 영향을 역시 Western blotting으로 관찰하였다. A549세포에 활성억제제인 ZnPP나 HO-1 small interfering RNA (siRNA)을 주입하여 cisplatin과의 병합요법시 생존율의 배가효과 유무를 MTT 방법으로 확인하였고, 이러한 효과가 ROS 형성과 HO-1의 발현변화와 관련되는지를 알아보기 위해 $carboxy-H_2DCFDA$ 방법과 Western blotting을 통해 각각 확인하였다. 결 과: Cisplatin 처리시 다른 세포주에 비해 A549 세포가 의의 있게 내성을 보였다. $10{\mu}M$의 농도에서 시간 의존적으로 HO-1, Nrf2, MAPK의 발현이 증가하였고, MAPK 억제제들을 전 처치하였을 때 cisplatin에 의해 유도된 HO-1과 Nrf2의 발현이 억제됨을 확인하였다. HO-1의 활성억제제인 ZnPP와 HO-1 siRNA를 통해 HO-1 mRNA를 직접 억제하는 방법으로 cisplatin과 병합치료시 단독치료에 비해 의의 있는 생존율의 감소를 보였다. 이러한 효과는 활성산소종의 생성 증가와 HO-1의 발현억제에 의한 결과임을 확인하였다. 결 론: Cisplatin 처리시 HO-1의 발현은 MAPKNrf2-HO-1의 경로를 통해 증가하였고, 부분적으로 치료에 대한 내성과 관련이 있었으며, ZnPP 등의 활성억제제나 siRNA를 통한 knock-down 방법으로 HO-1 을 표적으로 억제하는 치료방법을 통해 cisplatin의 항암제 감수성을 증가시켰다.

• Biomolecules & Therapeutics
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• 제26권6호
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• pp.584-590
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• 2018

Osteoporosis development is closely associated with oxidative stress and reactive oxygen species (ROS). Taurine has potential antioxidant effects, but its role in osteoblasts is not clearly understood. The aim of this study was to determine the protective effects and mechanisms of actions of taurine on hydrogen peroxide ($H_2O_2$)-induced oxidative stress in osteoblast cells. UMR-106 cells were treated with taurine prior to $H_2O_2$ exposure. After treatment, cell viability, apoptosis, intracellular ROS production, malondialdehyde content, and alkaline phosphate (ALP) activity were measured. We also investigated the protein levels of ${\beta}-catenin$, ERK, CHOP and NF-E2-related factor 2 (Nrf2) along with the mRNA levels of Nrf2 downstream antioxidants. The results showed that pretreatment of taurine could reverse the inhibition of cell viability and suppress the induced apoptosis in a dose-dependent manner: taurine significantly reduced $H_2O_2$-induced oxidative damage and expression of CHOP, while it induced protein expression of Nrf2 and ${\beta}-catenin$ and activated ERK phosphorylation. DKK1, a Wnt/${\beta}-catenin$ signaling inhibitor, significantly suppressed the taurine-induced Nrf2 signaling pathway and increased CHOP. Activation of ERK signaling mediated by taurine in the presence of $H_2O_2$ was significantly inhibited by DKK1. These data demonstrated that taurine protects osteoblast cells against oxidative damage via Wnt/${\beta}-catenin$-mediated activation of the ERK signaling pathway.

• Journal of Microbiology and Biotechnology
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• 제34권3호
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• pp.596-605
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• 2024

Anthocyanins belong to phenolic pigments and are known to have various pharmacological activities. This study aimed to investigate whether anthocyanins could inhibit hydrogen peroxide (H₂O₂)-induced oxidative damage in human retinal pigment epithelial ARPE-19 cells. Our results indicated that anthocyanins suppressed H₂O₂-induced genotoxicity, while inhibiting reactive oxygen species (ROS) production and preserving diminished glutathione. Anthocyanins also suppressed H₂O₂-induced apoptosis by reversing the Bcl-2/Bax ratio and inhibiting caspase-3 activation. Additionally, anthocyanins attenuated the release of cytochrome c into the cytosol, which was achieved by interfering with mitochondrial membrane disruption. Moreover, anthocyanins increased the expression of heme oxygenase-1 (HO-1) as well as its activity, which was correlated with the phosphorylation and nuclear translocation of nuclear factor-erythroid-2 related factor 2 (Nrf2). However, the cytoprotective and anti-apoptotic effects of anthocyanins were significantly attenuated by the HO-1 inhibitor, demonstrating that anthocyanins promoted Nrf2-induced HO-1 activity to prevent ARPE-19 cells from oxidative stress. Therefore, our findings suggest that anthocyanins, as Nrf2 activators, have potent ROS scavenging activity and may have the potential to protect ocular injury caused by oxidative stress.