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Featured researches published by You-Chang Oh.


The American Journal of Chinese Medicine | 2012

Anti-inflammatory effect of Citrus Unshiu peel in LPS-stimulated RAW 264.7 macrophage cells.

You-Chang Oh; Won-Kyung Cho; Yun Hee Jeong; Ga Young Im; Min Cheol Yang; Youn-Hwan Hwang; Jin Yeul Ma

Citrus Unshiu peel (CUP) has been traditionally used in East Asia as a drug for the treatment of vomiting and dyspepsia. However, its effects on inflammation remain unknown. In this study, we investigated the effects of CUP on the production of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The research focused on determining whether CUP could inhibit the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2 and the activation of nuclear factor (NF)-κB, mitogen-activated protein kinases (MAPKs), as well as the secretion of nitric oxide (NO), prostaglandin (PG) E(2), tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in LPS-stimulated RAW 264.7 cells. We found that CUP represses LPS-induced iNOS and COX-2 gene expression as well as NO, PGE(2), TNF-α and IL-6 production. Additionally, CUP inhibited the LPS-induced phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun NH(2)-terminal kinase (JNK) MAPK, and suppressed IκBα degradation and nuclear translocation of NF-κB. Collectively, our results indicate that CUP inhibits the production of various inflammatory mediators via blockade of MAPK phosphorylation pursuant to the inhibition of IκBα degradation and the nuclear translocation of NF-κB. These findings are the first to clarify the mechanism underlying the anti-inflammatory effect exerted by CUP in RAW 264.7 macrophage cells stimulated by inflammatory agents.


International Immunopharmacology | 2012

Anti-inflammatory effect of Lycium Fruit water extract in lipopolysaccharide-stimulated RAW 264.7 macrophage cells

You-Chang Oh; Won-Kyung Cho; Ga Young Im; Yun Hee Jeong; Youn-Hwan Hwang; Jin Yeul Ma

Lycium Fruit has been used as a traditional drug for low back pain and chronic cough in east-Asian countries. However, inhibitory effects of Lycium Fruit water extract (LFWE) on inflammation remain unknown. In this study, we investigated the inhibitory effects of LFWE on pro-inflammatory mediator production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. LFWE inhibited LPS-induced nitric oxide (NO), prostaglandin (PG) E₂, tumor necrosis factor (TNF)-α and interleukin (IL)-6 production as well as their synthesizing enzyme inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 gene expression. Furthermore, LFWE inhibited phosphorylations of extracellular signal-regulated kinase (ERK), p38 and c-Jun NH₂-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs) as well as suppression of IκBα degradation and nuclear translocation of nuclear factor (NF)-κB upon LPS stimulation. In addition, LFWE suppressed NO, PGE₂, TNF-α and IL-6 production in LPS-stimulated peritoneal macrophage cells. Taken together, our results suggest that LFWE inhibits the production of various inflammatory mediators via blockade on the MAPKs and NF-κB pathways. This finding first explains the mechanism of anti-inflammatory effect by LFWE in LPS-stimulated macrophage cells.


BMC Complementary and Alternative Medicine | 2012

Fermentation by Lactobacillus enhances anti-inflammatory effect of Oyaksungisan on LPS-stimulated RAW 264.7 mouse macrophage cells

You-Chang Oh; Won-Kyung Cho; Jin Hui Oh; Ga Young Im; Yun Hee Jeong; Min Cheol Yang; Jin Yeul Ma

BackgroundOyaksungisan (OY) has been used as a traditional drug in east-Asian countries. However, its effect on inflammation still remains unknown. In this study, to provide insight into the biological effects of OY and OY fermented by Lactobacillus, we investigated their effects on lipopolysaccharide (LPS)-mediated inflammation in the RAW 264.7 murine macrophage cells.MethodsThe investigation was focused on whether OY and fermented OYs could inhibit the production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin (PG) E2 as well as the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-α, interleukin (IL)-6, nuclear factor (NF)-κB and mitogen-activated protein kinases (MAPKs) in LPS-stimulated RAW 264.7 cells.ResultsWe found that OY inhibits a little LPS-induced NO, PGE2, TNF-α and IL-6 productions as well as the expressions of iNOS and COX-2. Interestingly, the fermentation significantly increased its inhibitory effect on the expression of all pro-inflammatory mediators. Furthermore, the fermented OYs exhibited elevated inhibition on the translocation of NF-κB p65 through reduced IκBα degradation as well as the phosphorylations of extracellular signal-regulated kinase (ERK), p38 and c-Jun NH2-terminal kinase (JNK) MAPKs than untreated control or original OY.ConclusionsFinally, the fermentation by Lactobacillus potentiates the anti-inflammatory effect of OY by inhibiting NF-κB and MAPK activity in the macrophage cells.


BMC Complementary and Alternative Medicine | 2014

Oryeongsan inhibits LPS-induced production of inflammatory mediators via blockade of the NF-kappaB, MAPK pathways and leads to HO-1 induction in macrophage cells

You-Chang Oh; Yun Hee Jeong; Jeong-Ho Ha; Won-Kyung Cho; Jin Yeul Ma

BackgroundOryeongsan (OR) is an herbal medication used in east-Asian traditional medicine to treat dysuresia, such as urinary frequency, hematuria, and dysuria due to renal disease and chronic nephritis. Recent studies showed that protective effect against acute gastric mucosal injury and an inhibitory effect on the renin-angiotensin-aldosterone pathway of OR. However, its effect on inflammation still remains unknown. In this study, to provide insight into the biological effects of OR, we investigated their effects on lipopolysaccharide (LPS)-mediated inflammation in the RAW 264.7 macrophage cells.MethodsWe investigated the pharmacological and biological effects of OR on the production of pro-inflammatory cytokines, inflammatory mediators, and related products through Enzyme-linked immunosorbent assay (ELISA), reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Also, we examined the activation and suppression of nuclear factor (NF)-kappaB and mitogen-activated protein kinases (MAPKs) pathways in LPS-stimulated macrophages via Western blot analysis in order to explore inhibitory mechanism of OR.ResultsOR had anti-inflammatory effects by inhibiting the production of nitric oxide (NO), tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-1beta. In addition, it strongly suppressed cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), NO synthesizing enzymes. It also induced heme oxygenase (HO)-1 expression and inhibited NF-kappaB signaling pathway activation and phosphorylation of MAPKs.ConclusionsWe further demonstrate the anti-inflammatory effects and inhibitory mechanism of OR in LPS-stimulated macrophages for the first time. OR contains strong anti-inflammatory activity and affects various mechanism pathways including NF-kappaB, MAPKs and HO-1. Our results suggest that OR has potential value to be developed as an inflammatory therapeutic agent from a natural substance.


International Journal of Molecular Sciences | 2015

Anti-Inflammatory and Analgesic Effects of Pyeongwisan on LPS-Stimulated Murine Macrophages and Mouse Models of Acetic Acid-Induced Writhing Response and Xylene-Induced Ear Edema

You-Chang Oh; Yun Hee Jeong; Won-Kyung Cho; Jeong-Ho Ha; Min Jung Gu; Jin Yeul Ma

Pyeongwisan (PW) is an herbal medication used in traditional East Asian medicine to treat anorexia, abdominal distension, borborygmus and diarrhea caused by gastric catarrh, atony and dilatation. However, its effects on inflammation-related diseases are unknown. In this study, we investigated the biological effects of PW on lipopolysaccharide (LPS)-mediated inflammation in macrophages and on local inflammation in vivo. We investigated the biological effects of PW on the production of inflammatory mediators, pro-inflammatory cytokines and related products as well as the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) in LPS-stimulated macrophages. Additionally, we evaluated the analgesic effect on the acetic acid-induced writhing response and the inhibitory activity on xylene-induced ear edema in mice. PW showed anti-inflammatory effects by inhibiting the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) and interleukin-1β (IL-1β). In addition, PW strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression and inhibited NF-κB activation and MAPK phosphorylation. Also, PW suppressed TNF-α, IL-6 and IL-1β cytokine production in LPS-stimulated peritoneal macrophage cells. Furthermore, PW showed an analgesic effect on the writhing response and an inhibitory effect on mice ear edema. We demonstrated the anti-inflammatory effects and inhibitory mechanism in macrophages as well as inhibitory activity of PW in vivo for the first time. Our results suggest the potential value of PW as an inflammatory therapeutic agent developed from a natural substance.


Evidence-based Complementary and Alternative Medicine | 2012

A Novel Herbal Medicine KIOM-MA Exerts an Anti-Inflammatory Effect in LPS-Stimulated RAW 264.7 Macrophage Cells

You-Chang Oh; Won-Kyung Cho; Yun Hee Jeong; Ga Young Im; Aeyung Kim; Youn-Hwan Hwang; Taesoo Kim; Kwang Hoon Song; Jin Yeul Ma

KIOM-MA was recently reported as a novel herbal medicine effective for atopic dermatitis and asthma. In this study, we have demonstrated the inhibitory effect of KIOM-MA on proinflammatory mediator produced in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. KIOM-MA significantly inhibited the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) as well as nitric oxide (NO) and prostaglandin E2 (PGE2). Consistent with the inhibitory effect on PGE2, KIOM-MA suppresses the LPS-induced migration of macrophages and gelatinase activity and the expression of matrix metalloprotease-9 (MMP-9) in a dose-dependent manner. Additionally, KIOM-MA showed a strong suppressive effect on the inflammatory cytokines production such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). We also found that KIOM-MA inhibits the activation of nuclear factor-κB (NF-κB) and represses the activity of extracellular signal-regulated kinase (ERK), p38, and c-Jun NH2-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs). Taken together, we elucidated the mechanism of anti-inflammatory effect of KIOM-MA using RAW 264.7 cells stimulated by LPS.


Food and Chemical Toxicology | 2013

Anti-inflammatory effect of Sosihotang via inhibition of nuclear factor-κB and mitogen-activated protein kinases signaling pathways in lipopolysaccharide-stimulated RAW 264.7 macrophage cells

You-Chang Oh; Won-Kyung Cho; Yun Hee Jeong; Ga Young Im; Kwang Jin Lee; Hye Jin Yang; Jin Yeul Ma

Sosihotang (SO) is an herbal medication, which has been widely used to treat fever, chill and vomiting due to common cold in east-Asian countries. In this study, to provide insight into the effects of SO on inflammation, we investigated its effect on pro-inflammatory mediator production in RAW 264.7 cells and mouse peritoneal macrophages using lipopolysaccharide (LPS) stimulation. SO significantly inhibited the production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-6 as well as gene expression of inducible nitric oxide synthase (iNOS), its synthesizing enzyme. In addition, SO inhibited nuclear factor (NF)-κB activation and suppressed extracellular signal-regulated kinase (ERK), p38 and c- Jun NH(2)-terminal kinase (JNK) mitogen-activated protein kinases (MAPKs) phosphorylation. Furthermore, we found SO suppresses the production of NO and IL-6 in LPS-stimulated peritoneal macrophage cells. High performance liquid chromatography (HPLC) analysis showed SO contains many active anti-inflammatory constituents such as liquiritigenin, baicalin, baicalein, glycyrrhizin and wogonin. We first elucidated the inhibitory mechanism of SO on inflammation induced by LPS in macrophage cells. Our results suggest SO has potential to be developed as a therapeutic agent for various inflammatory diseases.


Mediators of Inflammation | 2016

Anti-Inflammatory Effect of Rhapontici Radix Ethanol Extract via Inhibition of NF-κB and MAPK and Induction of HO-1 in Macrophages

Yun Hee Jeong; You-Chang Oh; Won-Kyung Cho; Nam-Hui Yim; Jin Yeul Ma

Rhapontici Radix (RR) has been used in traditional medicine in East Asia and has been shown to have various beneficial effects. However, its biological properties or mechanism on inflammation-related diseases is unknown. The goal of this study was to determine the anti-inflammatory activity and underlying molecular mechanisms of Rhapontici Radix ethanol extract (RRE). The inhibitory effect of RRE on the production of NO, cytokines, inflammatory-related proteins, and mRNAs in LPS-stimulated macrophages was determined by the Griess assay, ELISA, Western blot analysis, and real-time RT-PCR, respectively. Our results indicate that treatment with RRE significantly inhibited the secretion of NO and inflammatory cytokines in RAW 264.7 cells and mouse peritoneal macrophages without cytotoxicity. We also found that RRE strongly suppressed the expression of iNOS and COX-2 and induced HO-1 expression. It also prevented nuclear translocation of NF-κB by inhibiting the phosphorylation and degradation of IκBα. Furthermore, the phosphorylation of MAPKs in LPS-stimulated RAW 264.7 cells was significantly inhibited by RRE. These findings suggest that RRE may operate as an effective anti-inflammatory agent by inhibiting the activation of NF-κB and MAPK signaling pathways and inducing HO-1 expression in macrophages. Our results suggest that RRE has potential value as candidate to inflammatory therapeutic phytomedicine.


Journal of Automated Methods & Management in Chemistry | 2014

Extraction and Bioactivity Analysis of Major Flavones Compounds from Scutellaria baicalensis Using In Vitro Assay and Online Screening HPLC-ABTS System

Kwang Jin Lee; Pil Mun Jung; You-Chang Oh; Na-Young Song; Tae Soo Kim; Jin Yeul Ma

The extraction efficiency of a number of solvent compositions for the improvement of bioactive compounds yield from S. baicalensis has been investigated. Also, free radical scavengers in the glycoside baicalin (BG), wogonoside (WG), aglycon baicalein (B), and wogonin (W) compounds of S. baicalensis were screened, identified, and quantified using coupled offline ABTS and online screening HPLC-ABTS assay. Increasing ethanol content fractions resulted in decreased extract yield of bioactive compounds. In this case, the best yield of 37.01 mg/g in BG, WG, B, and W compounds was obtained by a dipping method with an extraction time of 4 h. In addition, the yield (43.05%) and IC50 (34.04 μg/mL) determined through ABTS assay of the 60% aqueous ethanol extract were the most satisfactory of all solvent solutions tested. This result shows that an online screening HPLC-ABTS assay can be a powerful technique for the rapid characterization of bioactivity compounds in plant extracts. Moreover, their anti-inflammatory activities were evaluated via analyzed inhibitory effect on NO and inflammatory cytokine production. Furthermore, WG and W exhibited the strong inhibitory effects on inflammatory mediator production including NO, IL-6, and IL-1β in LPS-stimulated RAW 264.7 macrophages.


International Journal of Molecular Sciences | 2014

Inhibitory Effects of Palmultang on Inflammatory Mediator Production Related to Suppression of NF-κB and MAPK Pathways and Induction of HO-1 Expression in Macrophages

You-Chang Oh; Yun Hee Jeong; Won-Kyung Cho; Min-Jung Gu; Jin Yeul Ma

Palmultang (PM) is an herbal decoction that has been used to treat anorexia, anemia, general prostration, and weakness due to chronic illness since medieval times in Korea, China, and Japan. The present study focused on the inhibitory effects of PM on the production of inflammatory factors and on the activation of mechanisms in murine macrophages. PM suppressed the expression of nitric oxide (NO), inflammatory cytokines and inflammatory proteins by inhibiting nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling pathways and by inducing heme oxygenase (HO)-1 expression. Collectively, our results explain the anti-inflammatory effect and inhibitory mechanism of PM in macrophages stimulated with lipopolysaccharide (LPS).

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