Yong-Ouk You

Prof. Dr. Yong-Ouk You

orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2005 in Journal of Medicinal Food
Verified
Journal Article
Closed access
HYHyeon-Hee Yu
Hyeon-Hee Yu
KKKang-Ju Kim
Kang-Ju Kim
JCJeong-Dan Cha
Jeong-Dan Cha
HKHae-Kyoung Kim
Hae-Kyoung Kim
YLYoung-Eun Lee
Young-Eun Lee
YYYong-Ouk You
Yong-Ouk You
Methicillin-resistant Staphylococcus aureus (MRSA) bacteria have been responsible for substantial morbidity and mortality in hospitals because they usually have multidrug resistance. Some natural products are candidates as new antibiotic substances. In the present study, we investigated the antimicrobial activity of berberine, the main antibacterial substance of Coptidis rhizoma (Coptis chinensis Franch) and Phellodendri cortex (Phellodendron amurense Ruprecht), against clinical isolates of MRSA, and the effects of berberine on the adhesion to MRSA and intracellular invasion into human gingival fibroblasts (HGFs). Berberine showed antimicrobial activity against all tested strains of MRSA. Minimum inhibition concentrations (MICs) of berberine against MRSA ranged from 32 to 128 microg/mL. Ninety percent inhibition of MRSA was obtained with 64 microg/mL or less of berberine. In the checkerboard dilution test, berberine markedly lowered the MICs of ampicillin and oxacillin against MRSA. An additive effect was found between berberine and ampicillin, and a synergistic effect was found between berberine and oxacillin against MRSA. In the presence of 1-50 microg/mL berberine, MRSA adhesion and intracellular invasion were notably decreased compared with the vehicle-treated control group. These results suggest that berberine may have antimicrobial activity and the potential to restore the effectiveness of beta-lactam antibiotics against MRSA, and inhibit the MRSA adhesion and intracellular invasion in HGFs.

1 August 2006 in European Journal of Pharmacology
Verified
Journal Article
Closed access
SJSeon Il Jang
Seon Il Jang
HKHyung Jin Kim
Hyung Jin Kim
YKYoung-Jun Kim
Young-Jun Kim
SJSeung-Il Jeong
Seung-Il Jeong
YYYong-Ouk You
Yong-Ouk You

1 November 2003 in Planta Medica
Verified
Journal Article
Closed access
PDF file
SJSeon-Il Jang
Seon-Il Jang
SJSeung-Il Jeong
Seung-Il Jeong
KKKang-Ju Kim
Kang-Ju Kim
HKHyung-Jin Kim
Hyung-Jin Kim
HYHyeon-Hee Yu
Hyeon-Hee Yu
YYYong-Ouk You
Yong-Ouk You
The inhibitory effects of tanshinone IIA, a diterpene isolated from Salvia miltiorrhiza root, on the production of nitric oxide (NO), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), and the expression of inducible nitric oxide synthase (iNOS) were investigated in activated RAW 264.7 cells. This compound markedly inhibited the production of NO, IL-1β and TNF-α, and suppressed the expression of iNOS in a dose-dependent manner. These results suggest that the traditional use of S. miltiorrhiza as an anti-inflammatory herbal medicine may be explained, in part, by the inhibition of NO, IL-1β, IL-6 and TNF-α production, and expression of iNOS.

17 May 2013 in Rheumatology
Verified
Journal Article
Open access
PDF file
JHJin-Ki Hwang
Jin-Ki Hwang
ENEun-Mi Noh
Eun-Mi Noh
SMSu-Jeong Moon
Su-Jeong Moon
JKJeong-Mi Kim
Jeong-Mi Kim
KKKang-Beom Kwon
Kang-Beom Kwon
YLYoung-Rae Lee
Young-Rae Lee
Objective. Emodin (3-methyl-1,6,8-trihydroxyanthraquinone) is one of the active components present in the root and rhizome of Rheum palmatum. It has been shown to contain biological activity (antitumour, antibacterial, diuretic and vasorelaxant effects). However, the mechanisms underlying the anti-arthritic effect of emodin have not been elucidated. Here we investigated whether emodin treatment would modulate the severity of the disease in an experimental arthritis model. Methods. We evaluated the effects of emodin on CIA mice in vivo. Results. The pathological processes of RA are mediated by a number of cytokines and MMPs. Expression of these proinflammatory mediators is controlled by nuclear factor-κB (NF-κB). This study was performed to explore the effect of emodin on control of the NF-κB activation pathway and to investigate whether emodin has anti-inflammatory effects in CIA mice in vivo. Emodin inhibited the nuclear translocation and DNA binding of NF-κB subunits, which were correlated with its inhibitory effect on cytoplasmic IκBα degradation in CIA mice. These events further suppressed chemokine production and MMP expression. In addition, emodin inhibited the osteoclast differentiation induced by M-CSF and receptor activation of NF-κB ligand in bone marrow macrophages. Conclusion. These findings suggest that emodin exerts anti-inflammatory effects in CIA mice through inhibition of the NF-κB pathway and therefore may have therapeutic value for the treatment of RA.

1 September 2012 in Phytomedicine
Verified
Journal Article
Closed access
JKJeong-Mi Kim
Jeong-Mi Kim
ENEun-Mi Noh
Eun-Mi Noh
KKKang-Beam Kwon
Kang-Beam Kwon
JKJong-Suk Kim
Jong-Suk Kim
YYYong-Ouk You
Yong-Ouk You
YLYoung-Rae Lee
Young-Rae Lee

19 October 2012 in Stem Cell Research & Therapy
Verified
Journal Article
Open access
PDF file
KAKentaro Akiyama
Kentaro Akiyama
YYYong-Ouk You
Yong-Ouk You
TYTakayoshi Yamaza
Takayoshi Yamaza
CCChider Chen
Chider Chen
LTLiang Tang
Liang Tang
SSSongtao Shi
Songtao Shi
Introduction: Bone marrow mesenchymal stem cells (BMMSCs) are a heterogeneous population of postnatal precursor cells with the capacity of adhering to culture dishes generating colony-forming unit-fibroblasts (CFU-F). Here we identify a new subset of BMMSCs that fail to adhere to plastic culture dishes and remain in culture suspension (S-BMMSCs).Methods: To catch S-BMMSCs, we used BMMSCs-produced extracellular cell matrix (ECM)-coated dishes. Isolated S-BMMSCs were analyzed byin vitrostem cell analysis approaches, including flow cytometry, inductive multiple differentiation, western blot andin vivoimplantation to assess the bone regeneration ability of S-BMMSCs. Furthermore, we performed systemic S-BMMSCs transplantation to treat systemic lupus erythematosus (SLE)-like MRL/lprmice.Results: S-BMMSCs are capable of adhering to ECM-coated dishes and showing mesenchymal stem cell characteristics with distinction from hematopoietic cells as evidenced by co-expression of CD73 or Oct-4 with CD34, forming a single colony cluster on ECM, and failure to differentiate into hematopoietic cell lineage. Moreover, we found that culture-expanded S-BMMSCs exhibited significantly increased immunomodulatory capacitiesin vitroand an efficacious treatment for SLE-like MRL/lprmice by rebalancing regulatory T cells (Tregs) and T helper 17 cells (Th17) through high NO production.Conclusions: These data suggest that it is feasible to improve immunotherapy by identifying a new subset BMMSCs.