Kim, Hyun Suk;Lee, Jae Hoon;Moon, Sun Hee;Ahn, Dong Uk;Paik, Hyun-Dong
Food Science of Animal Resources
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v.40
no.2
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pp.274-285
/
2020
In this study, ovalbumin (OVA) hydrolysates were prepared using various proteolytic enzymes and the anti-inflammatory activities of the hydrolysates were determined. Also, the potential application of OVA as a functional food material was discussed. The effect of OVA hydrolysates on the inhibition of nitric oxide (NO) production was evaluated via the Griess reaction, and their effects on the expression of inducible NO synthase (inducible nitric oxide synthase, iNOS) were assessed using the quantitative real-time PCR and Western blotting. To determine the mechanism by which OVA hydrolysates activate macrophages, pathways associated with the mitogen-activated protein kinase (MAPK) signaling were evaluated. When the OVA hydrolysates were added to RAW 264.7 cells without lipopolysaccharide (LPS) stimulation, they did not affect the production of NO. However, both the OVA-Protex 6L hydrolysate (OHPT) and OVA-trypsin hydrolysate (OHT) inhibited NO production dose-dependently in LPS-stimulated RAW 264.7 cells. Especially, OHT showed a strong NO-inhibitory activity (62.35% at 2 mg/mL) and suppressed iNOS production and the mRNA expression for iNOS (p<0.05). Also, OHT treatment decreased the phosphorylation levels of Jun amino-terminal kinases (JNK) and extracellular signal-regulated kinases (ERK) in the MAPK signaling pathway. These findings suggested that OVA hydrolysates could be used as an anti-inflammatory agent that prevent the overproduction of NO.
This study was conducted to analyze the molecular mechanisms responsible for anti-proliferation effects of glaucocalyxin A in cultured MCF-7 and Hs578T breast cancer cells. The concentration that reduced cell viability to 50% (IC50) after 72 h treatment was derived and potential molecular mechanisms of anti-proliferation using the IC50 were investigated as changes in cell cycle arrest and apoptosis. Gene and protein expression changes related to apoptosis were investigated by semi-quantitative RT-PCR and western blotting, respectively. Involvement of phosphorylated mitogen-activated protein kinases and JNK signaling in regulation of these molecules was characterized by western blotting. Cell viability decreased in a concentration-dependent manner and the IC50 was determined as $1{\mu}M$ in MCF-7 and $4{\mu}M$ in Hs578T cell. Subsequently, we demonstrated that the GLA-induced MCF-7 and Hst578T cell death was due to cell cycle arrest at the G2/M transition and was associated with activation of the c-jun N-terminal kinase (JNK) pathway. We conclude that GLA has the potential to inhibit the proliferation of human breast cancer cells through the JNK pathway and suggest its application forthe effective therapy for patients with breast cancer.
Silwal, Prashanta;Lim, Kyu;Heo, Jun-Young;Park, Jong IL;Namgung, Uk;Park, Seung-Kiel
The Korean Journal of Physiology and Pharmacology
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v.22
no.4
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pp.379-389
/
2018
A nucleobase adenine is a fundamental component of nucleic acids and adenine nucleotides. Various biological roles of adenine have been discovered. It is not produced from degradation of adenine nucleotides in mammals but produced mainly during polyamine synthesis by dividing cells. Anti-inflammatory roles of adenine have been supported in IgE-mediated allergic reactions, immunological functions of lymphocytes and dextran sodium sulfate-induced colitis. However adenine effects on Toll-like receptor 4 (TLR4)-mediated inflammation by lipopolysaccharide (LPS), a cell wall component of Gram negative bacteria, is not examined. Here we investigated anti-inflammatory roles of adenine in LPS-stimulated immune cells, including a macrophage cell line RAW264.7 and bone marrow derived mast cells (BMMCs) and peritoneal cells in mice. In RAW264.7 cells stimulated with LPS, adenine inhibited production of pro-inflammatory cytokines $TNF-{\alpha}$ and IL-6 and inflammatory lipid mediators, prostaglandin $E_2$ and leukotriene $B_4$. Adenine impeded signaling pathways eliciting production of these inflammatory mediators. It suppressed $I{\kappa}B$ phosphorylation, nuclear translocation of nuclear factor ${\kappa}B$ ($NF-{\kappa}B$), phosphorylation of Akt and mitogen activated protein kinases (MAPKs) JNK and ERK. Although adenine raised cellular AMP which could activate AMP-dependent protein kinase (AMPK), the enzyme activity was not enhanced. In BMMCs, adenine inhibited the LPS-induced production of $TNF-{\alpha}$, IL-6 and IL-13 and also hindered phosphorylation of $NF-{\kappa}B$ and Akt. In peritoneal cavity, adenine suppressed the LPS-induced production of $TNF-{\alpha}$ and IL-6 by peritoneal cells in mice. These results show that adenine attenuates the LPS-induced inflammatory reactions.
Objective : The object of this study is to confirm the immune enhancement effect of Rubus coreanus Miquel (RC) (30% EtOH extract) on RAW264.7 mouse macrophage cell line. Methods : RAW264.7 cells were treated with $10-500{\mu}g/mL$ RC for 24 hours. Cell viability was then measured using WST assays. Levels of intracellular NO and ROS were measured by Griess reagent and DCFH-DA staining respectively. Levels of iNOS and COX-2 mRNA was determined by RT-PCR. Secretion levels of IL-$1{\beta}$ and IL-6 cytokines were evaluated by sandwich ELISA assay. Western blot analysis was performed to measure the levels of intracellular molecules related to MAPKs pathways. Results : RC suppressed the growth of RAW264.7 cells. RC increased the production of NO and ROS. RC increased the mRNA and protein levels of COX-2 and iNOS. RC augmented the levels of secreted IL-$1{\beta}$ and IL-6 cytokines. RC increased MAPKs phosphorylation. Conclusion : In summary, our result shows that RC has inflammatory effect increasing the levels of NO, ROS and secreted cytokines and activating MAPKs. Hence, RC seems to have an immune enhancement effect.
Proceedings of the Korean Society of Applied Pharmacology
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2007.11a
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pp.153-158
/
2007
Background: Naturally occurring antioxidants were used to regulate the skin damage caused by ultraviolet (UV) radiation because several antioxidants have demonstrated that they can inhibit wrinkle formation through prevention of matrix metalloproteinases (MMPs) and/or increase of collagen synthesis. We examined the effect of oral administration of the antioxidant mixture ("L-Skin Care") on UVB-induced wrinkle formation. In addition, we investigated the possible molecular mechanisms of photoprotection against UVB through inhibition of collagen-degrading MMP activity or through enhancing of pro collagen synthesis in mouse dorsal skin. Methods: Female SKH-l hairless mice were orally administrated "L-Skin Care" (test group) or vehicle (control group) for 10 weeks with UVB irradiation by three times a week. The intensity of irradiation was gradually increased from 30 to $180mJ/cm^2$. Microtopographic and histological assessments of the dorsal skins were carried out at the end of 10 weeks to evaluate wrinkle formation. Western blot analysis and EMSA were also carried out to investigate the changes in the balance of collagen synthesis and collagen degradation. Results: Our "L-Skin Care" significantly reduced UVB-induced wrinkle formation, accompanied by significant reduction of epidermal thickness, and UVB-induced hyperplasia, acanthosis and hyperkeratosis. Oral administration of "L-Skin Care" significantly prevented UVB-induced expressions of MMPs, mitogen-activated protein (MAP) kinases and activation of activator protein (AP)-1 transcriptional factor in addition to enhanced type I procollagen and transforming growth factor-$\beta$ (TGF-$\beta$) expression. Conclusion: Oral administration of "L-Skin Care" significantly inhibited wrinkle formation caused by chronic UVB irradiation through significant inhibition of UVB-induced MMP activity accompanied with enhancement of collagen synthesis.
Kim, Dong Hoi;Kim, Dae Won;Jung, Bo Hyun;Lee, Jong Hun;Lee, Heesu;Hwang, Gwi Seo;Kang, Ki Sung;Lee, Jae Wook
Journal of Ginseng Research
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v.43
no.2
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pp.326-334
/
2019
Background: The objective of our study was to analyze the neuroprotective effects of ginsenoside derivatives Rb1, Rb2, Rc, Rd, Rg1, and Rg3 against glutamate-mediated neurotoxicity in HT22 hippocampal mouse neuron cells. Methods: The neuroprotective effect of ginsenosides were evaluated by measuring cell viability. Protein expressions of mitogen-activated protein kinase (MAPK), Bcl2, Bax, and apoptosis-inducing factor (AIF) were determined by Western blot analysis. The occurrence of apoptotic and death cells was determined by flow cytometry. Cellular level of $Ca^{2+}$ and reactive oxygen species (ROS) levels were evaluated by image analysis using the fluorescent probes Fluor-3 and 2',7'-dichlorodihydrofluorescein diacetate, respectively. In vivo efficacy of neuroprotection was evaluated using the Mongolian gerbil of ischemic brain injury model. Result: Reduction of cell viability by glutamate (5 mM) was significantly suppressed by treatment with ginsenoside Rb2. Phosphorylation of MAPKs, Bax, and nuclear AIF was gradually increased by treatment with 5 mM of glutamate and decreased by co-treatment with Rb2. The occurrence of apoptotic cells was decreased by treatment with Rb2 ($25.7{\mu}M$). Cellular $Ca^{2+}$ and ROS levels were decreased in the presence of Rb2, and in vivo data indicated that Rb2 treatment (10 mg/kg) significantly diminished the number of degenerated neurons. Conclusion: Our results suggest that Rb2 possesses neuroprotective properties that suppress glutamate-induced neurotoxicity. The molecular mechanism of Rb2 is by suppressing the MAPKs activity and AIF translocation.
Lee, Ye Eun;Park, Hong Jin;Park, Chung-berm;Hwang, Seung-mi
Korean Journal of Food Science and Technology
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v.53
no.2
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pp.115-120
/
2021
Scutellaria baicalensis has been used as a traditional medicine for diarrhea, dysentery, hypertension, hemorrhaging, insomnia, inflammation, and respiratory infections. This study examined the anti-inflammatory effect of Scutellaria baicalensis water extract (SWE) in lipopolysaccharide (LPS)-induced RAW 264.7 cells. To evaluate the anti-inflammatory effect of SWE, RAW 264.7 macrophages were stimulated with LPS to induce the production of inflammation-related factors, which were measured by western blotting. In RAW 264.7 cells, SWE inhibited the production of nitric oxide (NO) without causing cell toxicity. SWE also reduced the expression of inducible NO synthase and cyclooxygenase-2 protein, as well as the production of pro-inflammatory cytokines (such as tumor necrosis factor-α). The phosphorylation levels of the mitogen-activated protein kinase family members, such as JNK and p38, were also reduced by SWE. Thus, SWE could be used as a potential anti-inflammatory agent.
Objective : Gardeniae Fructus (GF) has bitter and cold nature. Thus, it has been traditionally prescribed in processed form roasted with ginger juice for patients with a weak stomach. This study investigated the effects of processed GF in tert-butyl hydroperoxide (tBHP)-treated gastric epithelial cells. Methods : Processed GF was made by applying 40% ginger juice or 10% ethanol for 24 h and then roasting at 150℃ for 5 minutes. Apoptosis was determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Mitochondrial membrane potential (MMP) was monitored by flow cytometry using the membrane permeable fluorescent dye Rh123. Protein expression was measured by Western blot analysis. Results : Cell viability was reduced by tBHP and restored by ethanol extract of GF (GFE). In the TUNEL assay, it was found that cell death by tBHP was due to apoptosis, and GFE had an anti-apoptotic effect. Processed GF roasted with ginger juice showed the best anti-apoptotic effect. Processed GF also inhibited MMP loss and restored tBHP-induced changes in expression levels of apoptosis-related proteins. Increased ROS production and GSH depletion after tBHP treatment were significantly reduced by processed GF. In addition, tBHP-induced activation of mitogen-activated protein kinase (MAPK) was inhibited by processed GF. Conclusion : These results demonstrate that the processed GF is able to protect gastric epithelial cells from oxidative stress-induced cell death with antiapoptotic and antioxidant activity. In addition, it shows that the processing of GF, which have been traditionally used for gastrointestinal protection, partially have scientific validity.
Jang, Eun Jeong;Kim, Heejeong;Baek, Seung Eun;Jeon, Eun Yeong;Kim, Ji Won;Kim, Ju Yeon;Kim, Chi Dae
The Korean Journal of Physiology and Pharmacology
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v.26
no.5
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pp.389-396
/
2022
The increased expression of receptors for advanced glycation end-product (RAGE) is known as a key player in the progression of vascular remodeling. However, the precise signal pathways regulating RAGE expression in vascular smooth muscle cells (VSMCs) in the injured vasculatures are unclear. Given the importance of mitogen-activated protein kinase (MAPK) signaling in cell proliferation, we investigated the importance of MAPK signaling in high-mobility group box 1 (HMGB1)-induced RAGE expression in VSMCs. In HMGB1 (100 ng/ml)-stimulated human VSMCs, the expression of RAGE mRNA and protein was increased in association with an increase in AGE-induced VSMC proliferation. The HMGB1-induced RAGE expression was attenuated in cells pretreated with inhibitors for ERK (PD98059, 10 μM) and p38 MAPK (SB203580, 10 μM) as well as in cells deficient in ERK and p38 MAPK using siRNAs, but not in cells deficient of JNK signaling. In cells stimulated with HMGB1, the phosphorylation of ERK, JNK, and p38 MAPK was increased. This increase in ERK and p38 MAPK phosphorylation was inhibited by p38 MAPK and ERK inhibitors, respectively, but not by JNK inhibitor. Moreover, AGE-induced VSMC proliferation in HMGB1-stimulated cells was attenuated in cells treated with ERK and p38 MAPK inhibitors. Taken together, our results indicate that ERK and p38 MAPK signaling are involved in RAGE expression in HMGB1-stimulated VSMCs. Thus, the ERK/p38 MAPK-RAGE signaling axis in VSMCs was suggested as a potential therapeutic target for vascular remodeling in the injured vasculatures.
Objectives : This study evaluates how various traditional Korean herbal medicines assess MUC5AC expression for esophageal mucosal defense and analyzes the associated mechanisms involved in inflammation. Methods : Forty types of traditional Korean herbal medicines were assessed for in vitro antioxidant activities, and the real-time PCR method was employed to analyze MUC5AC expression under pH 4.5 conditions in human esophageal epithelial cells (HET-1A). Eight types of Korean herbal medicines were evaluated for in vitro antioxidant activities, and Reactive oxygen specise (ROS) expression was analyzed under bile salt (480 𝜇M) and pH 5.5 conditions in human esophageal epithelial cells (HET-1A). Simulation experiments involving bile salts and acidity were conducted for one hour to assess the efficacy of four drugs, and the activities of Mitogen-activated Protein Kinase (MEK), Nuclear Factor Kappa B (NF-𝜅B), and Cyclooxygenase-2 (COX-2) were detected through Western blot analysis. Results : Compared to the Normal group, the Control group exhibited higher ROS generation. Such increased ROS levels were significantly reduced by four extracts: Citrus Unshius Pericarpium (CUP), Cnidium officinale Rhizoma (CR), Ginseng Radix (GR), and Linderae Radix (LR). The protein expression of COX-2 decreased with the treatment of LR, CUP, and CR. Particularly, CUP and CR exhibited superior effects compared to other groups in inhibiting the phosphorylation of NF-𝜅B. Conclusion : Based on the results obtained, we have identified drugs that inhibit oxidative stress and inflammation caused by bile acid in esophageal epithelial cells. Our future plans involve comparing and analyzing the efficacy of these herbal medicines through animal experiments.
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