Endogenous Ligand for GPR120, Docosahexaenoic Acid, Exerts Benign Metabolic Effects on the Skeletal Muscles via AMP-activated Protein Kinase Pathway

Kim, Nami,Lee, Jung Ok,Lee, Hye Jeong,Kim, Hyung Ip,Kim, Joong Kwan,Lee, Yong Woo,Lee, Soo Kyung,Kim, Su Jin,Park, Sun Hwa,Kim, Hyeon Soo American Society for Biochemistry and Molecular Bi 2015 The Journal of biological chemistry Vol.290 No.33

<P>Docosahexaenoic acid (DHA) is an endogenous ligand of G protein-coupled receptor 120 (GPR120). However, the mechanisms underlying DHA action are poorly understood. In this study, DHA stimulated glucose uptake in the skeletal muscles in an AMP-activated protein kinase (AMPK)-dependent manner. GPR120-mediated increase in intracellular Ca<SUP>2+</SUP> was critical for DHA-mediated AMPK phosphorylation and glucose uptake. In addition, DHA stimulated GLUT4 translocation AMPK-dependently. Inhibition of AMPK and Ca<SUP>2+</SUP>/calmodulin-dependent protein kinase kinase blocked DHA-induced glucose uptake. DHA and GW9508, a GPR120 agonist, increased GPR120 expression. DHA-mediated glucose uptake was not observed in GPR120 knockdown conditions. DHA increased AMPK phosphorylation, glucose uptake, and intracellular Ca<SUP>2+</SUP> concentration in primary cultured myoblasts. Taken together, these results indicated that the beneficial metabolic role of DHA was attributed to its ability to regulate glucose via the GPR120-mediated AMPK pathway in the skeletal muscles.</P>

The effect of applying ethnicity-specific spirometric reference equations to Asian migrant workers in Korea

Nami Kim,Se-Yeong Kim,Yoojun Song,Chunhui Suh,Kun-Hyung Kim,Jeong-Ho Kim,Byung-Chul Son,Chae-Kwan Lee,Jong-Tae Lee 대한직업환경의학회 2015 대한직업환경의학회지 Vol.27 No.-

Objectives: Asian migrant workers in Korea have various ethnicities. The purpose of this study was to evaluate the difference in spirometric interpretation made using the set of third National Health and Nutrition Examination Survey (NHANES III) reference equations and the relevant ethnicity-specific reference sets. Methods: Spirometry was performed on 166 migrant and 498 Korean male workers between March and November 2012. We analyzed the spirometric data of healthy never-smokers. Spirometric patterns were evaluated using the NHANES III reference set and some relevant ethnicity-specific equations (Eom’s equation for Koreans, Ip’s equation for East Asians, Crapo’s equation for Central Asians, Memon’s equation for South Asians, and Gnanou’s equation for Southeast Asian people). Results: In all migrant groups except the Central Asian group, the forced expiratory volume in 1 second percentage (FEV₁%) and forced vital capacity percentage (FVC%) calculated using each of the ethnicity-specific reference equations considered were significantly higher than those calculated using the NHANES III reference set. This study showed that in the evaluation of the spirometric result of subjects from Southeast Asia or South Asia, the percentage of cases with an abnormal FEV₁ or FVC increased when the NHANES III set of equations was used as compared to when the ethnicity-specific equations were used. Conclusions: We found that the spirometric results of all ethnic groups were higher and the composition of the abnormal spirometric result was lower when the ethnicity-specific reference equations were used instead of the NHANES III reference set.

Discordance in Spirometric Interpretations Based on Korean and Non-Korean Reference Equations

Nami Kim,Mi-Hee Park,Se-yeong Kim,Chunhui Suh,Sangyoon Lee,Kun-Hyung Kim,Chae-Kwan Lee,Dae-Hwan Kim,Jong-Tae Lee 대한직업환경의학회 2013 대한직업환경의학회지 Vol.25 No.-

Objectives: Korean regression models for spirometric reference values are different from those of other ethnic groups. The purpose of this study was to evaluate discordance in spirometric interpretations based on using Korean reference equations versus non-Korean reference equations. Methods: Spirometry was performed on 825 Korean male workers from April 2009 to November 2011. The spirometric patterns and disease severity were evaluated using two Korean equations (Choi’s and Lee’s) and three equations for Caucasians (NHANES III, Morris’s, and Knudson’s), and the results of Choi’s equation were compared with the non-Korean equations. The spirometric patterns were defined as normal, restrictive, and mild and moderate obstructive. Results: The mean differences in the FEV1% and FVC% between the two Korean equations were 2.0 ± 1.3% and 3.5 ± 2.2%, respectively. Morris’s equation had the greatest difference in the FEV1% from Choi’s equation: 32.9 ± 8.5%. Knudson’s equation had the greatest difference in the FVC% from Choi’s equation: 10.5 ± 6.5%. Conclusions: The two Korean equations shared similar characteristics of spirometric interpretation. The spirometric interpretations of Choi’s equation were significantly different from those of Morris’s equation and Knudson’s equation.

AMPK, a metabolic sensor, is involved in isoeugenol-induced glucose uptake in muscle cells

Kim, Nami,Lee, Jung Ok,Lee, Hye Jeong,Lee, Yong Woo,Kim, Hyung Ip,Kim, Su Jin,Park, Sun Hwa,Lee, Chul Su,Ryoo, Sun Woo,Hwang, Geum-Sook,Kim, Hyeon Soo Bioscientifica Ltd 2016 The Journal of endocrinology Vol.228 No.2

<P>Isoeugenol exerts various beneficial effects on human health. However, the mechanisms underlying these effects are poorly understood. In this study, we observed that isoeugenol activated AMP-activated protein kinase (AMPK) and increased glucose uptake in rat L6 myotubes. Isoeugenol-induced increase in intracellular calcium concentration and glucose uptake was inhibited by STO-609, an inhibitor of calcium/calmodulin-dependent protein kinase kinase (CaMKK). Isoeugenol also increased the phosphorylation of protein kinase C-α (PKCα). Chelation of calcium with BAPTA-AM blocked isoeugenol-induced AMPK phosphorylation and glucose uptake. Isoeugenol stimulated p38MAPK phosphorylation that was inhibited after pretreatment with compound C, an AMPK inhibitor. Isoeugenol also increased glucose transporter type 4 (GLUT4) expression and its translocation to the plasma membrane. GLUT4 translocation was not observed after the inhibition of AMPK and CaMKK. In addition, isoeugenol activated the Akt substrate 160 (AS160) pathway, which is downstream of the p38MAPK pathway. Knockdown of the gene encoding AS160 inhibited isoeugenol-induced glucose uptake. Together, these results indicate that isoeugenol exerts beneficial health effects by activating the AMPK/p38MAPK/AS160 pathways in skeletal muscle.</P>

Development of Double Mutant Waxy-Super Sweet Corn Hybrids in Korea

Soon-Kwon Kim,Mira Lee,Ik-Hwi Kim,SangChul Lee,Hyoung Wook Kim,Nami Yoon,Hyunji Kim 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Visfatin, a novel adipokine, stimulates glucose uptake through the Ca²⁺-dependent AMPK–p38 MAPK pathway in C2C12 skeletal muscle cells

Lee, Jung Ok,Kim, Nami,Lee, Hye Jeong,Lee, Yong Woo,Kim, Joong Kwan,Kim, Hyung Ip,Lee, Soo Kyung,Kim, Su Jin,Park, Sun Hwa,Kim, Hyeon Soo Journal of Endocrinology (Ltd. by Guarantee) 2015 Journal of molecular endocrinology Vol.54 No.3

<P>Visfatin is a novel adipocytokine produced by visceral fat. In the present study, visfatin increased AMP-activated protein kinase (AMPK) phosphorylation in mouse C2C12 skeletal muscle cells. It also increased phosphorylation of the insulin receptor, whose knockdown blocked visfatin-induced AMPK phosphorylation and glucose uptake. Visfatin stimulated glucose uptake in differentiated skeletal muscle cells. However, inhibition of AMPK alpha 2 with an inhibitor or with knockdown of AMPK alpha 2 using siRNA blocked visfatin-induced glucose uptake, which indicates that visfatin stimulates glucose uptake through the AMPK alpha 2 pathway. Visfatin increased the intracellular Ca2+ concentration. STO-609, a calmodulin-dependent protein kinase kinase inhibitor, blocked visfatin-induced AMPK phosphorylation and glucose uptake. Visfatin-mediated activation of p38 MAPK was AMPK alpha 2-dependent. Furthermore, both inhibition and knockdown of p38 MAPK blocked visfatin-induced glucose uptake. Visfatin increased glucose transporter type 4 (GLUT4) mRNA and protein levels. In addition, visfatin stimulated the translocation of GLUT4 to the plasma membrane, and this effect was suppressed by AMPK alpha 2 inhibition. The present results indicate that visfatin plays an important role in glucose metabolism via the Ca2+-mediated AMPK-p38 MAPK pathway.</P>

High lead exposure in two leaded bronze ingot foundry workers

Yoojun Song,Chunhui Suh,Shin-Ae Kim,Nami Kim,Sung-Min Kim,Seong-Wook Jeong,Se-Yeong Kim,Kun-Hyung Kim,Jeong-Ho Kim,Byung-Chul Son,Chae-Kwan Lee,Jong-Tae Lee 대한직업환경의학회 2014 대한직업환경의학회지 Vol.26 No.-

Background: Awareness about lead poisoning in South Korea has increased; however, occupational exposures occurring in small-scale businesses have not been thoroughly investigated. We report two cases of high lead exposure in a leaded bronze ingot foundry. Case presentation: Two employees, a 54-year-old primary operator and a 46-year-old assistant, at a small-scale metalworking company who had been employed for 18 years and 1 month, respectively, showed elevated blood lead levels (61.1 μg/dL and 51.7 μg/dL, respectively) at an occupational health checkup. Neither worker complained of abnormal symptoms nor signs related to lead poisoning. Health assessment follow-ups were conducted and biological exposure indices of lead were calculated every four weeks. After the initial follow-up assessment, both workers were relocated from the foundry process to the metalworking process. In addition, a localized exhaust system was installed after the second follow-up. Conclusions: Foundry workers in a small-scale businesses might be at high risk of lead exposure because these businesses might be vulnerable to poor industrial hygiene. Therefore, regular occupational health checkups are required.

Irisin, a Novel Myokine, Regulates Glucose Uptake in Skeletal Muscle Cells via AMPK

Lee, Hye Jeong,Lee, Jung Ok,Kim, Nami,Kim, Joong Kwan,Kim, Hyung Ip,Lee, Yong Woo,Kim, Su Jin,Choi, Jong-Il,Oh, Yoonji,Kim, Jeong Hyun,Hwang, Suyeon-,Park, Sun Hwa,Kim, Hyeon Soo Endocrine Society 2015 Molecular endocrinology Vol.29 No.6

<P>Irisin is a novel myokine produced by skeletal muscle. However, its metabolic role is poorly understood. In the present study, irisin induced glucose uptake in differentiated skeletal muscle cells. It increased AMP-activated protein kinase (AMPK) phosphorylation and the inhibition of AMPK blocked glucose uptake. It also increased reactive oxygen species (ROS) generation. N-acetyl cysteine, a ROS scavenger, blocked irisin-induced AMPK phosphorylation. Moreover, irisin activated p38 MAPK in an AMPK-dependent manner. The inhibition and knockdown of p38 MAPK blocked irisin-induced glucose uptake. A colorimetric absorbance assay showed that irisin stimulated the translocation of glucose transporter type 4 to the plasma membrane and that this effect was suppressed in cells pretreated with a p38 MAPK inhibitor or p38 MAPK small interfering RNA. In primary cultured myoblast cells, irisin increased the concentration of intracellular calcium. STO-609, a calcium/calmodulin-dependent protein kinase kinase inhibitor, blocked irisin-induced AMPK phosphorylation, implying that calcium is involved in irisin-mediated signaling. Our results suggest that irisin plays an important role in glucose metabolism via the ROS-mediated AMPK pathway in skeletal muscle cells.</P>

“Lord, I Am a Father!” The Transnational Evangelical Men’s Movement and the Advent of “Benevolent” Patriarchy

KIM, Nami 이화여자대학교 아시아여성학센터 2011 Asian Journal of Women's Studies(AJWS) Vol.17 No.1

Begun as a small faith-based organization in South Korea in the late twentieth century, the Father School has evolved into a transnational evangelical men’s movement, aiming to bring positive changes not only in the family but also in the church and larger society. Through a critical examination of the Father School’s remaking of manhood and womanhood by analyzing what I call the “scripts of the wounded father” and “scripts of the wise mother and good wife,” this article argues that despite its seemingly commendable goals such as the reduction of family violence and an increase in communication among family members, the Father School does not alter hierarchical gender relations and the hetero-patriarchal structure of the family and church. Instead, the remaking of manhood through the reformation of hegemonic masculinity “softens” such a structure by calling for “benevolent” patriarchy. Simultaneously, the Father School encourages women’s re-domestication by legitimizing the roles of wife and mother as women’s most valuable functions.

Mosaic-like Monolayer of Graphene Oxide Sheets Decorated with Tetrabutylammonium Ions

Kim, Jung Woo,Kang, Dongwoo,Kim, Tae Hyeong,Lee, Sung Guk,Byun, Nami,Lee, Dong Wook,Seo, Byung Hwa,Ruoff, Rodney S.,Shin, Hyeon Suk American Chemical Society 2013 ACS NANO Vol.7 No.9

<P>We report the fabrication of mosaic-like monolayers of graphene oxide (G-O) coated with tetrabutylammonium ions (TBA) using a simple spin-coating method. The TBA-coated G-O (TG-O) sheets were prepared by “spontaneous exfoliation” of graphite oxide intercalated with tetrabutylammonium hydroxide (TBAOH) in the wet state, without the need for sonication. Mosaic-like monolayers could be formed on a variety of substrates such as Si wafer (coated with the thin native oxide), SiO<SUB>2</SUB>/Si wafer, graphene grown by chemical vapor deposition and then transferred on SiO<SUB>2</SUB>/Si wafer, Au film on Si wafer, and Cu foil. The mosaic-like monolayer of TG-O was compared with monolayers of G-O and TG-O prepared using a Langmuir–Blodgett (LB) trough. The formation of the mosaic-like TG-O monolayer films was attributed to (1) weakening of the electrostatic repulsion between G-O sheets by TBA, and (2) prevention of the overlap and stacking of TG-O sheets by disruption of the hydrogen bonding between the basal plane of one sheet and the basal plane or edge of another, by adsorbed TBA. External reflection FTIR spectroscopy showed that spectral features of the mosaic-like monolayer of TG-O made by simple spin-coating were the same as those for the monolayer fabricated using the LB assembly, indicating the same spatial orientations of functional groups. This study provides a very simple route to a complete monolayer of G-O without the need for an LB trough.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2013/ancac3.2013.7.issue-9/nn403363s/production/images/medium/nn-2013-03363s_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn403363s'>ACS Electronic Supporting Info</A></P>