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Dive into the research topics where Nam-Kyung Im is active.

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Featured researches published by Nam-Kyung Im.


Journal of Ginseng Research | 2011

Antioxidant Effects of Fermented Red Ginseng Extracts in Streptozotocin- Induced Diabetic Rats

Hyun-Jeong Kim; Sung-Gyu Lee; In-Gyeong Chae; Mi-Jin Kim; Nam-Kyung Im; Mi-Hee Yu; Eun Ju Lee; In-Seon Lee

The antioxidant activities of fermented red ginseng (FRG) were investigated in vitro and in vivo. The contents of total polyphenol and total flavonoid in FRG extracts were 17.01±2.00 μg/mg and 18.42±3.97 μg/mg, respectively. These extracts were capable of directly scavenging α, α-diphenyl-picrylhydrazyl free radicals. The antioxidative effects of the FRG extracts in streptozotocin (STZ)-induced diabetic rats were also investigated. The activities of plasma alanine transaminase, aspartate transaminase, and γ-glutamyltransferase were significantly decreased by extract administration as compared to an STZ control group. Hepatic glutathione content depleted by STZ treatment was significantly increased by treatment of the FRG extracts, but the elevation of lipid peroxide content induced by STZ was significantly decreased by the extracts. Activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase decreased after STZ-treatment were recovered by the treatment of the FRG extracts. These results indicate that FRG extracts have antioxidative effets in STZ-induced diabetic rats.


Biochemical Pharmacology | 2010

Alisol-B, a novel phyto-steroid, suppresses the RANKL-induced osteoclast formation and prevents bone loss in mice

Ji-Won Lee; Yasuhiro Kobayashi; Yuko Nakamichi; Nobuyuki Udagawa; Naoyuki Takahashi; Nam-Kyung Im; Hwa-Jeong Seo; Won Bae Jeon; Takayuki Yonezawa; Byung-Yoon Cha; Je-Tae Woo

Osteoclasts, bone-resorbing multinucleated cells, are differentiated from hemopoietic progenitors of the monocyte/macrophage lineage. Bone resorption by osteoclasts is considered a potential therapeutic target to the treatment of erosive bone diseases, including osteoporosis, rheumatoid arthritis, and periodontitis. In the present study, we found that alisol-B, a phyto-steroid from Alisma orientale Juzepczuk, exhibited inhibitory effects on osteoclastogenesis both in vitro and in vivo. Although RT-PCR analysis showed that alisol-B did not affect the 1alpha,25(OH)(2)D(3)-induced expressions of RANKL, OPG and M-CSF mRNAs in osteoblasts, addition of alisol-B to co-cultures of mouse bone marrow cells and primary osteoblasts with 10(-8)M 1alpha,25(OH)(2)D(3) caused significant inhibition of osteoclastogenesis. We further examined the direct effects of alisol-B on osteoclast precursors. Alisol-B strongly inhibited RANKL-induced osteoclast formation when added during the early stage of cultures, suggesting that alisol-B acts on osteoclast precursors to inhibit RANKL/RANK signaling. Among the RANK signaling pathways, alisol-B inhibited the phosphorylation of JNK, which are upregulated in response to RANKL in bone marrow macrophages, alisol-B also inhibited RANKL-induced expression of NFATc1 and c-Fos, which are key transcription factors for osteoclastogenesis. In addition, alisol-B suppressed the pit-forming activity and disrupted the actin ring formation of mature osteoclasts. In a hypercalcemic mouse model induced by 2-methylene-19-nor-(20S)-1alpha,25(OH)(2)D(3) (2MD), an analog of 1alpha,25(OH)(2)D(3), administration of alisol-B significantly suppressed 2MD-induced hypercalcemia as resulting from the inhibition of osteoclastogenesis. Taken together, these findings suggest that alisol-B may be a potential novel therapeutic molecule for bone disorders by targeting the differentiation of osteoclasts as well as their functions.


Journal of Medicinal Food | 2012

Effect of Rosemarinus officinalis L. on MMP-9, MCP-1 Levels, and Cell Migration in RAW 264.7 and Smooth Muscle Cells

In Gyeong Chae; Mi Hee Yu; Nam-Kyung Im; Young Tae Jung; Jinho Lee; Kyung-Soo Chun; In-Seon Lee

Atherosclerosis is a chronic and progressive inflammatory disease. Novel anti-inflammatory therapies may have promise as treatment strategies for cardiovascular risk reduction. Rosemary (Rosemarinus officinalis L.) has been used in folk medicine to treat headaches, epilepsy, poor circulation, and many other ailments. It was found that rosemary could act as a stimulant and mild analgesic and could reduce inflammation. However, the mechanisms underlying the anti-inflammatory and antiatherosclerotic effects of rosemary need more study. This study investigated effects of the rosemary components, carnosic acid (CA), and carnosol (CAR), on cell migration. Monocyte chemoattractant protein-1 (MCP-1) and matrix metalloproteinase-9 (MMP-9) were determined by Western blot and gelatin zymography, respectively, in RAW 264.7 macrophages and vascular smooth muscle cells (VSMCs). VSMC migration was assessed by a Matrigel migration assay. Active compounds of rosemary extracts were also analyzed using a reversed-phase high-performance liquid chromatography. MMP-9 and MCP-1 activities were markedly diminished with methanol extract (RM), n-hexane fraction (RH), and CA in RAW 264.7 cells. RM, RH, CA, and CAR suppressed tumor necrosis factor-alpha-induced VSMC migration by inhibiting MMP-9 expression. Chromatograms of RM- and RH-containing CA and CAR revealed higher CA contents of RM (9.4%, 93.85 μg/mg dry wt.) and, especially, RH (18.4%, 184.00 μg/mg dry wt.), which were appreciably elevated compared with the similar CAR content in RM and RH (3.7%, 37.30 μg/mg dry wt.; and 2.5%, 25.05 μg/mg dry wt., respectively). Rosemary, especially its CA component, has potential antiatherosclerosis effects related to cell migration.


Journal of Medicinal Food | 2014

Delphinidin Suppresses PMA-Induced MMP-9 Expression by Blocking the NF-κB Activation Through MAPK Signaling Pathways in MCF-7 Human Breast Carcinoma Cells

Nam-Kyung Im; Won Jun Jang; Chul-Ho Jeong; Gil-Saeng Jeong

Matrix metalloproteinase-9 (MMP-9) plays an important role in the invasion and metastasis of cancer cells. The synthesis and secretion of MMP-9 can be stimulated by a variety of stimuli, including cytokines and phorbol 12-myristate 13-acetate (PMA), during various pathological processes, such as tumor invasion, atherosclerosis, inflammation, and rheumatoid arthritis, whereas MMP-2 is usually expressed constitutively. Delphinidin, an anthocyanidin present in pigmented fruits and vegetables, possesses potent antioxidant, anti-inflammatory, and antiangiogenic properties. In this study, we investigated the antiproliferative and antiinvasive effects of delphinidin on PMA-induced MMP-9 expression in MCF-7 human breast carcinoma cells using zymography, western blotting, reverse transcription-polymerase chain reaction, and Matrigel invasion assay. Delphinidin significantly suppressed PMA-induced MMP-9 protein expression in MCF-7 human breast carcinoma cells, and it also inhibited the MMP-9 gene transcriptional activity by blocking the activation of NFkappaB (NF-κB) through MAPK signaling pathways. Moreover, the Matrigel invasion assay showed that delphinidin reduces PMA-induced cancer cell invasion. These results suggest that delphinidin is a potential antimetastatic agent that suppresses PMA-induced cancer cell invasion through the specific inhibition of NF-κB-dependent MMP-9 gene expression.


International Immunopharmacology | 2015

RETRACTED: Pierisformoside B exhibits neuroprotective and anti-inflammatory effects in murine hippocampal and microglial cells via the HO-1/Nrf2-mediated pathway

Nam-Kyung Im; Wei Zhou; MinKyun Na; Gil-Saeng Jeong

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor. The authors have found multiple errors with the submission including but not limited to the incorporation of a figure (figure 6C) previously published in the Korean Journal of Pharmacognosy 2014. Apr, 45(2):161–167, http://kpubs.org/article/articleMain.kpubs?articleANo=HKSOBF_2014_v45n2_161. The authors extend an apology to readers and editors for this matter.


The American Journal of Chinese Medicine | 2014

Spatholobus suberectus Inhibits Osteoclastogenesis and Stimulates Chondrogenesis

Nam-Kyung Im; Sung-Gyu Lee; Dong-Sung Lee; Pil-Hoon Park; In-Seon Lee; Gil-Saeng Jeong

This study was carried out to investigate the effect of Spatholobus suberectus Dunn (SS) on the protection of chondral defect and inhibition of osteoclastogenesis. To examine these effects, we measured the matrix metalloproteinase (MMP) levels in SW1353 chondrosarcoma cells and performed tartrate-resistant acid phosphatase (TRAP) staining in bone marrow macrophage (BMM)-derived osteoclasts. To investigate the anti-osteoarthritis (OA) effects, we assessed TNF-α-induced MMP-1, -3, -9 and tissue inhibitors of matrix metalloproteinase (TIMP) expression levels in SW1353 cells. We observed that SS extract significantly inhibited MMP and TIMP expression in SW1353 cells. Also, SS extract inhibited the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. These results suggest that SS extract may have a potential in the treatment of bone loss and chondral defect by suppressing osteoclast differentiation and decreasing the expression of OA factors. Therefore, clarification of the mechanism of the action of SS extract and its active components is needed.


Journal of Life Science | 2008

Effects of Aralia continentalis Kitagawa on Antiplatelet and Antioxidative Activities.

Seun-Ah Yang; Nam-Kyung Im; Kwang-Hwan Jhee; In-Seon Lee

단삼 메탄올 추출물의 항혈전 및 항산화 효과를 확인하기 위하여 혈소판의 응고 억제효과, 혈장응고시간의 연장, 혈전용해 활성으로 항혈전 효과를 고찰하였으며 DPPH radical 소거능을 측정하여 항산화 효과를 검토하였다. 그 결과, 단삼의 메탄올 추출물은 항혈전과 항산화에 효과가 있는 것으로 나타났다. 이 추출물은 ...


Journal of Life Science | 2008

Antioxidant Effect of Oil Containing Cellulase-Treated Red Ginseng.

Hyun-Jeong Kim; Seun-Ah Yang; Nam-Kyung Im; Kwang-Hwan Jhee; In-Seon Lee

In this study we evaluated the method to develop red ginseng oil containing high content of phytochemicals by enzymes treatment. To select the optimum extraction process of red ginseng with oils, the antioxidant activities of red ginseng using various enzymes were measured. Red ginseng after 0.5% cellulase treatment for 1 hr at had higher antioxidant activity than the other conditions. We found that red ginseng/soybean oil extracted for 15 days at after 0.5% cellulase treatment increased DPPH radical scavenger activity and decreased the TBA and POV values. However, red ginseng/olive oil had little functional activities compare to the red ginseng/soybean 0il. We also analyzed vitamin A and E by HPLC and found that vitamin E was increased by 0.5% cellulase treatment in the oil. This is the first report that red ginseng oil extracted by enzyme treatment has various beneficial effects.


Journal of Life Science | 2013

Functionality Analysis of Rhus javanica Fermented by Lactobacillus spp.

Dong-Sung Lee; Min-Su Kang; Youn-Chul Kim; Nam-Kyung Im; Hyun-Su Kim; Gil-Saeng Jeong

To determine the potential function of Rhus javanica in Korean medicine, it was fermented with each strain of Lactobacillus spp. Each strain of Lactobacillus spp. was inoculated in lactobacilli MRS broth, and 5 mg/ml of methanol extract of Rhus javanica was added. In mouse hippocampal HT22 cells, ethyl acetate extract of R. javanica fermented with L. brevis KCTC 3498 induced heme oxygenase-1 expression and showed a significant cytoprotective effect on glutamate-induced oxidative damage. The cytoprotective effect was related to the transcription of the nuclear factor E2-related factor2 (Nrf2), which is responsible for the induction of heme oxygenase-1 within the nucleus. The antimicrobial, antioxidant, and heme oxygenase-1 expression activities of fermented R. javanica were measured after extraction with ethyl acetate. R. javanica fermented with L. plantarum subsp. plantarum KCTC 3108, L. fermentum KCTC 3112, and L. brevis KCTC 3498 had higher antioxidant activity than nonfermented R. javanica. The fermented R. javanica with L. plantarum subsp. plantarum KCTC 3108, L. casei KCTC 3109 after ethyl acetate extraction showed antibacterial activity against Bacillus subtilis PCI 219, Escherichia coli KCTC 1682, Shigella flexneri KCTC 2517, Vibrio parahaemolyticus KCTC 7471, and Pseudomonas aeruginosa KCTC 2004. An ethyl acetate extract of the fermented R. javanica with Lactobacillus brevis KCTC 3498 exhibited stronger antibacterial activity than a nonfermented one against strains of B. subtilis PCI 219, E. coli KCTC 1682, S. flexneri KCTC 2517, and V. parahaemolyticus KCTC 7471.


Journal of Life Science | 2010

Effects of Inhaling Essential Oils from Lavender, Silver Fir, Grapefruit on the Restraint Stress in Mice

Seun-Ah Yang; Sang-Kyung Jeon; Eun-Jung Lee; Nam-Kyung Im; Chang-Hyun Shim; In-Seon Lee

The effects of inhaling three essential oils (lavender [Lavendular angustifolia], silver fir [Abies alba], and grapefruit [Citrus paradise]) against restraint stress were investigated in mice. Serum cortisol levels were significantly increased in the 1h-restraint group. Also, silver fir and grapefruit oils prevented the elevation of cortisol levels under experimental conditions. Inhalation of 10% lavender oil for 30 min before inducing stress significantly inhibited restraint-induced hypothermia. We also investigated the effects of restraint stress on triglycerides, total cholesterol, and high-density lipoprotein cholesterol. It was found that the concentration of triglycerides in the serum samples increased after restraint stress. Silver fir essential oil inhibited elevation of triglyceride levels. Taken all together, the correlation of herb essential oil inhalation against restraint stress in animals can partly be explained.

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Hyun-Jeong Kim

Seoul National University

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Kwang-Hwan Jhee

Kumoh National Institute of Technology

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Eun Ju Lee

Seoul National University

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