http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kim, Ji Hye,Yoon, Sei Mee,Song, Sun U.,Park, Sang Gyu,Kim, Won-Serk,Park, In Guk,Lee, Jinu,Sung, Jong-Hyuk MDPI 2016 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.17 No.9
<P>Hypoxia has diverse stimulatory effects on human adipose-derived stem cells (ASCs). In the present study, we investigated whether hypoxic culture conditions (2% O<SUB>2</SUB>) suppress spontaneous mineralization and osteogenic differentiation of ASCs. We also investigated signaling pathways and molecular mechanisms involved in this process. We found that hypoxia suppressed spontaneous mineralization and osteogenic differentiation of ASCs, and up-regulated mRNA and protein expression of Insulin-like growth factor binding proteins (IGFBPs) in ASCs. Although treatment with recombinant IGFBPs did not affect osteogenic differentiation of ASCs, siRNA-mediated inhibition of IGFBP3 attenuated hypoxia-suppressed osteogenic differentiation of ASCs. In contrast, overexpression of IGFBP3 via lentiviral vectors inhibited ASC osteogenic differentiation. These results indicate that hypoxia suppresses spontaneous mineralization and osteogenic differentiation of ASCs via intracellular IGFBP3 up-regulation. We determined that reactive oxygen species (ROS) generation followed by activation of the MAPK and PI3K/Akt pathways play pivotal roles in IGFBP3 expression under hypoxia. For example, ROS scavengers and inhibitors for MAPK and PI3K/Akt pathways attenuated the hypoxia-induced IGFBP3 expression. Inhibition of Elk1 and NF-κB through siRNA transfection also led to down-regulation of IGFBP3 mRNA expression. We next addressed the proliferative potential of ASCs with overexpressed IGFBP3, but IGFBP3 overexpression reduced the proliferation of ASCs. In addition, hypoxia reduced the osteogenic differentiation of bone marrow-derived clonal mesenchymal stem cells. Collectively, our results indicate that hypoxia suppresses the osteogenic differentiation of mesenchymal stem cells via IGFBP3 up-regulation.</P>
Mitochondria-Targeted Vitamin E Protects Skin from UVB-Irradiation
Kim, Won-Serk,Kim, Ikyon,Kim, Wang-Kyun,Choi, Ju-Yeon,Kim, Doo Yeong,Moon, Sung-Guk,Min, Hyung-Keun,Song, Min-Kyu,Sung, Jong-Hyuk The Korean Society of Applied Pharmacology 2016 Biomolecules & Therapeutics(구 응용약물학회지) Vol.24 No.3
Mitochondria-targeted vitamin E (MVE) is designed to accumulate within mitochondria and is applied to decrease mitochondrial oxidative damage. However, the protective effects of MVE in skin cells have not been identified. We investigated the protective effect of MVE against UVB in dermal fibroblasts and immortalized human keratinocyte cell line (HaCaT). In addition, we studied the wound-healing effect of MVE in animal models. We found that MVE increased the proliferation and survival of fibroblasts at low concentration (i.e., nM ranges). In addition, MVE increased collagen production and downregulated matrix metalloproteinase1. MVE also increased the proliferation and survival of HaCaT cells. UVB increased reactive oxygen species (ROS) production in fibroblasts and HaCaT cells, while MVE decreased ROS production at low concentration. In an animal experiment, MVE accelerated wound healing from laser-induced skin damage. These results collectively suggest that low dose MVE protects skin from UVB irradiation. Therefore, MVE can be developed as a cosmetic raw material.
Effect of Enhancers on in vitro and in vivo Skin Permeation and Deposition of S-Methyl-ʟ-Methionine
Kim, Ki Taek,Kim, Ji Su,Kim, Min-Hwan,Park, Ju-Hwan,Lee, Jae-Young,Lee, WooIn,Min, Kyung Kuk,Song, Min Gyu,Choi, Choon-Young,Kim, Won-Serk,Oh, Hee Kyung,Kim, Dae-Duk The Korean Society of Applied Pharmacology 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.4
S-methyl-$\small{L}$-methionine (SMM), also known as vitamin U, is commercially available as skin care cosmetic products for its wound healing and photoprotective effects. However, the low skin permeation expected of SMM due to its hydrophilic nature with a log P value of -3.3, has not been thoroughly addressed. The purpose of this study thus was to evaluate the effect of skin permeation enhancers on the skin permeation/deposition of SMM. Among the enhancers tested for the in vitro skin permeation and deposition of SMM, oleic acid showed the most significant enhancing effect. Moreover, the combination of oleic acid and ethanol further enhanced in vitro permeation and deposition of SMM through hairless mouse skin. Furthermore, the combination of oleic acid and ethanol significantly increased the in vivo deposition of SMM in the epidermis/dermis for 12 hr, which was high enough to exert a therapeutic effect. Therefore, based on the in vitro and in vivo studies, the combination of oleic acid and ethanol was shown to be effective in improving the topical skin delivery of SMM, which may be applied in the cosmetic production process for SMM.
Kim, Jin-Hyung,Kim, Dae-Won,Cheong, Min-Serk,Kim, Hoon-Sik,Mukherjee, Deb Kumar Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.6
The investigation of the catalytic activity of supported rhodium(I) complex [Rh(P-S)$(CO)_2$] (P-S; polymer anchored salicylic acid) toward the reductive carbonylation of nitrobenzene in DMF medium has been reported. Use of basic cocatalysts in the reaction medium enhanced the percentage of more useful phenyl carbamates. Spectroscopic studies indicate that the reaction proceeds through a dimer species [Rh(HS)(CO)(C(O)$OCH_3$)(${\mu}-OCH_3)]_2$ and phenyl isocyanate is formed as an intermediate. A plausible reaction mechanism based on the identification of reactive intermediates from the soluble rhodium variety has been proposed for the carbonylation process.
The pivotal role of PDGF and its receptor isoforms in adipose-derived stem cells.
Kim, Won-Serk,Park, Hyung-Sook,Sung, Jong-Hyuk Gutenberg 2015 Histology and histopathology Vol.30 No.7
<P>Platelet-derived growth factor (PDGF) is one of the growth factors that reportedly regulates cell growth and division of mesenchymal cells. Although PDGF isoforms and their receptors reportedly play a pivotal role in mesenchymal stem cell regulation, there is a paucity of literature reviewing the role of PDGF in adipose-derived stem cells (ASCs). Therefore, we summarized previous reports on the expression and functional roles of PDGF and its receptor isoforms in this review. In addition, we examined findings pertaining to underlying molecular mechanisms and signaling pathways with special focus on PDGF-D/PDGFRβ. ASCs only express PDGF-A, -C, -D, PDGFRα, and PDGFRβ. PDGFRα expression decreases with adipocyte lineage, while PDGFRβ inhibits white adipocyte differentiation. In addition, PDGFRβ induces proliferation, migration, and angiogenesis and up-regulates the expression of paracrine factors in ASCs. Although PDGF-B and -D mediate their functions mainly by PDGFRβ and ROS generation, there are many differences between them in terms of regulating ASCs. PDGF-D is endogenous, generates ROS via the mitochondrial electron transport system, and regulates the autocrine loop of ASCs in vivo. Furthermore, PDGF-D has stronger mitogenic effects than PDGF-B.</P>
Kim, Won-Serk,Han, Juhee,Hwang, Sung-Joo,Sung, Jong-Hyuk Informa UK, Ltd. 2014 Expert opinion on biological therapy Vol.14 No.8
<P><B><I>Introduction:</I></B> The self-renewal and differentiation of stem cells are controlled by both intrinsic factors and the surrounding microenvironment, which is known as the stem cell niche. Although the niches of adipose-derived stem cells (ASCs) are composed of diverse factors within the adipose tissue, the mechanisms by which niches are maintained, regulated and harmonized to support the ASCs are just beginning to be discovered.</P><P><B><I>Areas covered:</I></B> This review introduces the recent advances in the anatomic nature of the dynamic <I>in vivo</I> niches of ASCs. Additionally, new findings concerning the signaling pathways involved in the self-renewal, proliferation, differentiation and paracrine mechanisms will be described. Finally, we suggest optimized methods for expanding ASCs <I>in vitro</I> by mimicking the niche factors to enhance the regenerative potential of ASCs.</P><P><B><I>Expert opinion:</I></B> Fibroblast growth factor 2 is a self-renewal factor that can expand the lifespan of ASCs in long-term culture and platelet-derived growth factor-B/D has most potent mitogenic effects on short-term ASC expansion. Reactive oxygen species donors and stimulators of the phosphoinositide 3-kinase/protein kinase B and MAPK pathways can be used to increase the production yield of ASCs. Additionally, hypoxia can increase the proliferation of ASCs and priming under hypoxic conditions enhances the regenerative potential of ASCs.</P>