• Biomolecules & Therapeutics
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• 제25권3호
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• pp.272-278
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• 2017

Fucoidan has been reported to exhibit various beneficial activities ranging from to antivirus and anticancer properties. However, little information is available about the effects of fucoidan on cerebral ischemia-reperfusion injury (IRI). Our study aimed to explore the effects of fucoidan on cerebral IRI, as well as the underlying mechanisms. Sprague-Dawley (SD) rats were randomly subjected to four groups: Sham, IRI+saline (IRI+S), IRI+80 mg/kg fucoidan (IRI+F80), and IRI+160 mg/kg fucoidan (IRI+F160). Fucoidan (80 mg/kg or 160 mg/kg) was intraperitoneally injected from 7 days before the rats were induced to cerebral IRI model with middle cerebral artery occlusion (MCAO) method. At 24 h after reperfusion, neurological deficits and the total infarct volume were determined. The levels of inflammation-associated cytokines (interleukin (IL)-$1{\beta}$, IL-6, myeloperoxidase (MPO), and tumor necrosis factor (TNF)-${\alpha}$), oxidative stress-related proteins (malondialdehyde (MDA) and superoxide dismutase (SOD)) in the ischemic brain were measured by enzyme-linked immunosorbent assay (ELISA). Besides, the levels of apoptosis-related proteins (p-53, Bax, and B-cell lymphoma (Bcl)-2) and mitogen-activated protein kinase (MAPK) pathway (phosphorylation-extracellular signal-regulated kinase (p-ERK), p-c-Jun N-terminal kinase (JNK), and p-p38) were measured. Results showed that administration of fucoidan significantly reduced the neurological deficits and infarct volume compared to the IRI+S group in a dose-dependent manner. Also, fucoidan statistically decreased the levels of inflammation-associated cytokines, and oxidative stress-related proteins, inhibited apoptosis, and suppressed the MAPK pathway. So, Fucoidan plays a protective role in cerebral IRI might be by inhibition of MAPK pathway.

• Journal of Ginseng Research
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• 제47권2호
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• pp.183-192
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• 2023

Viral infections are known as one of the major factors causing death. Ginseng is a medicinal plant that demonstrated a wide range of antiviral potential, and saponins are the major bioactive ingredients in the genus Panax with vast therapeutic potential. Studies focusing on the antiviral activity of the genus Panax plant-derived agents (extracts and saponins) and their mechanisms were identified and summarized, including contributions mainly from January 2016 until January 2022. P. ginseng, P. notoginseng, and P. quinquefolius were included in the review as valuable medicinal herbs against infections with 14 types of viruses. Reports from 9 extracts and 12 bioactive saponins were included, with 6 types of protopanaxadiol (PPD) ginsenosides and 6 types of protopanaxatriol (PPT) ginsenosides. The mechanisms mainly involved the inhibition of viral attachment and replication, the modulation of immune response by regulating signaling pathways, including the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway, cystathionine γ-lyase (CSE)/hydrogen sulfide (H₂S) pathway, phosphoinositide-dependent kinase-1 (PDK1)/ protein kinase B (Akt) signaling pathway, c-Jun N-terminal kinase (JNK)/activator protein-1 (AP-1) pathway, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. This review includes detailed information about the mentioned antiviral effects of the genus Panax extracts and saponins in vitro and in vivo, and in human clinical trials, which provides a scientific basis for ginseng as an adjunctive therapeutic drug or nutraceutical.

• Journal of Photoscience
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• 제9권2호
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• pp.229-232
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• 2002

There are two distinct UV-responsive signaling pathways in UV-irradiated mammalian cells, i.e., the DNA damage-dependent and -independent pathways. The former occurs in nucleus and results in growth arrest and apoptosis via post-translational modification of p53. The latter is initiated by oxidative stress and/or by damages in cell membrane or cytoplasm, which activate signaling cascade through intracellular molecules including mitogen activated protein kinases (MAPK). In normal human fibroblastic cells, all of MAPK family members, extracellular signal-related kinases (ERK), c-Jun N-terminal kinases (JNK) and p38, were rapidly phosphorylated following UV-irradiation. ERK phosphorylation was suppressed by an inhibitor of receptor tyrosine kinases (RTK). As ERK usually responds to mitogenic stimuli from RTK ligands, UV-induced ERK phosphorylation may be linked to the proliferation of survived cells. In contrast, phosphorylation of JNK and p38, as well as apoptosis, were modulated by the level of UV-generated oxidative stress Therefore, JNK and p38 may take part in oxidative stress-mediated apoptosis. Phosphorylation of p53 at Ser and Thr residues are essential for stabilization and activation of p53. Among several sites reported, we confirmed phosphorylation at Ser-15 and Ser-392 after UV-irradiation. Both of these were inhibited by a phosphoinositide 3-kinase inhibitor, presumably due to the shutdown of signals from DNA damage to p53. Phosphorylation at Ser-392 was also sensitive to an antioxidant and a p38 inhibitor, suggesting that Ser-392 of p53 is one of the possible points where DNA damage-dependent and -independent apoptic signals merge. Thus, MAPK pathway links UV-induced intracellular signals to the nuclear responses and modifies DNA damage-dependent cellular outcome, resulting in the determination of cell death.

• International Journal of Oral Biology
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• 제42권3호
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• pp.91-97
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• 2017

Although anti-aging activities of melatonin, a hormone secreted by the pineal gland, have been reported in senescence-accelerated mouse models and several types of cells, its impact and mechanism on the senescence of human dental pulp cells (HDPCs) remains unknown. In this study, we examined the impact of melatonin on cellular premature senescence of HDPCs. Here, we found that melatonin markedly inhibited senescent characteristics of HDPCs after exposure to hydrogen peroxide ($H_2O_2$), including the increase in senescence-associated ${\beta}$-galactosidase (SA-${\beta}$-gal)-positive HDPCs and the upregulation of p21 protein, an indicator for senescence. In addition, as melatonin attenuated $H_2O_2$-stimulated phosphorylation of c-Jun N-terminal kinase (JNK), while selective inhibition of JNK activity with SP600125 significantly attenuated $H_2O_2$-induced increase in SA-beta-gal activity. Results reveal that melatonin antagonizes premature senescence of HDPCs via JNK pathway. Thus, melatonin may have therapeutic potential to prevent stress-induced premature senescence, possibly correlated with development of dental pulp diseases, and to maintain oral health across the life span.

• 생약학회지
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• 제43권4호
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• pp.316-322
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• 2012

Siegesbeckia Herba is known to have anti-oxidant, anti-inflammatory, anti-allergic and anti-tumor. The objective of this study is to explore the neuroprotective effect of Siegesbeckia Herba against glutamate-induced oxidative stress in mouse hippocampal HT22 cells. Siegesbeckia Herba 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 the mouse hippocampal HT22 cells. Especially, ethyl acetate fraction showed higher protective effect. In HT22 cell, Siegesbeckia Herba ethyl acetate fraction makes the nuclear accumulation of Nrf2. Further, we found that treatment with c-JUN N-terminal kinase (JNK) inhibitor (SP600125) reduced Siegesbeckia Herba ethyl acetate fraction induced HO-1 expression and Siegesbeckia Herba ethyl acetate fraction also increased JNK phosphorylation. In conclusion, the ethyl acetate fraction of 70% ethanol extract of Siegesbeckia Herba significantly protect glutamate-induced oxidative damage by induction of HO-1 via Nrf2 and JNK pathway in mouse hippocampal HT22. Taken together these finding suggest that Siegesbeckia Herba ethyl acetate fraction good source for taking active compounds and may be a potential therapeutic for brain disorder by targeting the oxidative stress of neuronal cell.

• Archives of Pharmacal Research
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• 제26권12호
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• pp.1055-1060
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• 2003

Lysophosphatidic acid (LPA) is a well-known mitogen in various cell types. However, we found that LPA inhibits melanocyte proliferation. Thus, we further investigated the possible signaling pathways involved in melanocyte growth inhibition. We first examined the regulation of the three major subfamilies of mitogen-activated protein (MAP) kinases and of the Akt pathway by LPA. The activations of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) were observed in concert with the inhibition of melanocyte proliferation by LPA, whereas p38 MAP kinase and Akt were not influenced by LPA. However, the specific inhibition of the ERK or JNK pathways by PD98059 or D-JNKI1, respectively, did not restore the antiproliferative effect. We next examined changes in the expression of cell cycle related proteins. LPA decreased cyclin $D_1 and cyclin D_2$ levels but increased $p21^{WAF1/CIP1}$ (p21) and $p27^{KIP1}$ (p27) levels, which are known inhibitors of cyclin-dependent kinase. Flow cytometric analysis showed the inhibition of DNA synthesis by a reduction in the S phase and an increase in the $G_0/G_1$ phase of the cell cycle. Our results suggest that LPA induces cell cycle arrest by regulating the expressions of cell cycle related proteins.

• 생약학회지
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• 제46권2호
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• pp.116-122
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• 2015

Keratinocytes are first barrier against outer challenges on skin. However, it is still largely unknown about effective protectors against ultraviolet B (UVB), and oxidative stress in human keratinocyte, HaCaT cells. Inducible heme oxygenase (HO)-1 acts against oxidants that are thought to play a role in the pathogenesis of skin disorders. Therefore, the purpose of this study was to evaluate the effect of Portulaca oleracea 70% EtOH extracts against hydrogen peroxide (H₂O₂)-induced oxidative stress in human keratinocytes, HaCaT cells. P. oleracea 70% EtOH extracts showed the potent protective effects on H₂O₂-induced toxicity by induced the expression of HO-1 in human keratinocyte, HaCaT cells. Furthermore, P. oleracea 70 % EtOH extracts caused the nuclear accumulation of nuclear factor E2-related factor 2 (Nrf2) in human keratinocytes, HaCaT cells. In addition, we found that treatment with c-Jun N-terminal kinase (JNK) inhibitor (SP600125) reduced P. oleracea 70% EtOH extracts-induced HO-1 expression, and JNK inhibitor (SP600125) also inhibited protective effects by P. oleracea 70% EtOH extracts. Therefore, these results suggest that P. oleracea 70 % EtOH extracts increases cellular resistance to H₂O₂-induced oxidative injury in human keratinocyte, HaCaT cells, presumably through JNK pathway-Nrf2-dependent HO-1 expression.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.107-107
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• 2022

Scrophularia koraiensis Nakai is widely used to remedy fever, edema, and neuritis. S. koraiensis has harpagoside and angoroside C, these compounds have been reported to alleviate inflammation, rheumatic diseases, and analgesic stimulation. We evaluated the anti-inflammatory effects of the ethanol extract of S. koraiensis (SKE) in lipopolysaccharides (LPS)-induced macrophages. At cellular levels, SKE decreased the production of nitric oxide (NO), the expression of inducible nitric oxide synthase (iNOS), and cytokines (IL-1b, TNF-a, and IL-6) under the LPS stimulation. SKE inhibited the phosphorylation of nuclear transcription factor-kappa B (NF-κB) p65 and its inhibitor (IκB-α). In addition, SKE suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 in the mitogen-activated protein kinase (MAPK) pathway. In conclusion, SKE could be considered a potential resource for attenuating inflammation response and it may be utilized in the material for cosmetics, food additives, and tea.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.96.1-96.1
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• 2003

Lysophosphatidic acid (LPA) is a well-known mitogen in various cell types. However, we were surprised to find that LPA inhibits melanocyte proliferation. Thus, we further investigated the possible signaling pathways involved in melanocyte growth inhibition. We first examined the regulation of the three major subfamilies of mitogen-activated protein (MAP) kinases and of the Akt pathway by LPA. The activations of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) were observed in concert with the inhibition of melanocyte proliferation by LPA, whereas p38 MAP kinase and Akt were not influenced by LPA. (omitted)

• 생명과학회지
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• 제25권9호
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• pp.984-992
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• 2015

혈근초(Sanguinaria canadensis)에서 처음 분리된 sanguinarine은 항산화, 항암 및 면역 증강 등의 효능이 있는 것으로 알려진 alkaloid 계열 물질 중의 하나이다. 본 연구에서는 인체간암 HepG2 세포를 대상으로 sanguinarine의 apoptosis 유도 효능 및 관련 기전 해석을 시도하였다. 본 연구의 결과에 의하면 sanguinarine은 HepG2 간암세포의 증식을 처리 농도 의존적으로 억제하였으며, 이는 apoptosis 유도와 연관성이 있었다. Sanguinarine에 의한 apoptosis 유도에는 Fas 및 Bax의 발현 증가, 미토콘드리아에서 세포질로의 cytochrome c 유리 및 MMPl (Δψm)의 소실을 동반하였다. Sanguinarine은 intrinsic 및 extrinsic apoptosis pathway의 활성에 관여하는 initiator caspase인 caspase-9와 -8의 활성과 effector caspase인 caspase-3의 활성 및 PARP 단백질의 단편화를 유발하였다. Sanguinarine은 또한 ROS의 생성을 촉진시켰으며, N-acetylcysteine 처리에 의한 ROS의 생성을 차단하였을 경우, sanguinarine에 의한 apoptosis 효능이 완벽하게 차단되었다. 아울러 sanguinarine은 Akt의 인산화를 억제한 반면, MAPKs의 인산화를 촉진시켰으며, 특히 PI3K와 ERK의 선택적 억제제는 sanguinarine에 의한 HepG2 간암세포의 증식을 더욱 억제시켰다. 따라서 sanguinarine에 의한 HepG2 간암세포의 apoptosis 유발에는 ROS 생성 의존적인 intrinsic 및 extrinsic signaling pathway가 동시에 활성화되며, PI3K/Akt 및 ERK 신호계가 관여함을 알 수 있었다.