Kang Hyun Leem

Prof. Kang Hyun Leem

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Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

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

Representative Publications

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Journal Article
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HPHae Jeong Park
Hae Jeong Park
ICInyeong Choi
Inyeong Choi
KLKang Hyun Leem
Kang Hyun Leem
Postmortem studies reveal that the brain pH in schizophrenia patients is lower than normal. The exact cause of this low pH is unclear, but increased lactate levels due to abnormal energy metabolism appear to be involved. Schizophrenia patients display distinct changes in mitochondria number, morphology, and function, and such changes promote anaerobic glycolysis, elevating lactate levels. pH can affect neuronal activity as H+ binds to numerous proteins in the nervous system and alters the structure and function of the bound proteins. There is growing evidence of pH change associated with cognition, emotion, and psychotic behaviors. Brain has delicate pH regulatory mechanisms to maintain normal pH in neurons/glia and extracellular fluid, and a change in these mechanisms can affect, or be affected by, neuronal activities associated with schizophrenia. In this review, we discuss the current understanding of the cause and effect of decreased brain pH in schizophrenia based on postmortem human brains, animal models, and cellular studies. The topic includes the factors causing decreased brain pH in schizophrenia, mitochondria dysfunction leading to altered energy metabolism, and pH effects on the pathophysiology of schizophrenia. We also review the acid/base transporters regulating pH in the nervous system and discuss the potential contribution of the major transporters, sodium hydrogen exchangers (NHEs), and sodium-coupled bicarbonate transporters (NCBTs), to schizophrenia.

1 April 2014 in Journal of Ginseng Research
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Journal Article
Open access
SLSena Lee
Sena Lee
MKMyung-Gyou Kim
Myung-Gyou Kim
SKSung Kwon Ko
Sung Kwon Ko
HKHye Kyung Kim
Hye Kyung Kim
KLKang Hyun Leem
Kang Hyun Leem
YKYoun Jung Kim
Youn Jung Kim
The protective effect of ginsenoside Re, isolated from ginseng berry, against acute gastric mucosal lesions was examined in rats with a single intraperitoneal injection of compound 48/80 (C48/80). Ginsenoside Re (20 mg/kg or 100 mg/kg) was orally administered 0.5 h prior to C48/80 treatment. Ginsenoside Re dose-dependently prevented gastric mucosal lesion development 3 h after C48/80 treatment. Increases in the activities of myeloperoxidase (MPO; an index of neutrophil infiltration) and xanthine oxidase (XO) and the content of thiobarbituric acid reactive substances (TBARS; an index of lipid peroxidation) and decreases in the contents of hexosamine (a marker of gastric mucus) and adherent mucus, which occurred in gastric mucosal tissues after C48/80 treatment, were significantly attenuated by ginsenoside Re. The elevation of Bax expression and the decrease in Bcl2 expression after C48/80 treatment were also attenuated by ginsenoside Re. Ginsenoside Re significantly attenuated all these changes 3 h after C48/80 treatment. These results indicate that orally administered ginsenoside Re protects against C48/80-induced acute gastric mucosal lesions in rats, possibly through its stimulatory action on gastric mucus synthesis and secretion, its inhibitory action on neutrophil infiltration, and enhanced lipid peroxidation in the gastric mucosal tissue.

20 December 2021 in Pharmaceuticals
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AAAkhtar Ali
Akhtar Ali
YPYoungJoon Park
YoungJoon Park
JLJeong-Hoon LEE
Jeong-Hoon LEE
Hyo-Jin AnHyo-Jin An
Hyo-Jin An
JJJong-Sik Jin
Jong-Sik Jin
WKWonnam Kim
Wonnam Kim
Osteoarthritis (OA) is a common degenerative joint disorder that affects joint function, mobility, and pain. The release of proinflammatory cytokines stimulates matrix metalloproteinases (MMPs) and aggrecanase production which further induces articular cartilage degradation. Hypertrophy-like changes in chondrocytes are considered to be an important feature of OA pathogenesis. A Glycyrrhiza new variety, Wongam (WG), was developed by the Korea Rural Development Administration to enhance the cultivation and quality of Glycyrrhizae Radix et Rhizoma (licorice). This study examined the regulatory effect of WG against hypertrophy-like changes such as RUNX2, Collagen X, VEGFA, MMP-13 induction, and Collagen II reduction induced by IL-1β in SW1353 human chondrocytes. Additionally, in silico methods were performed to identify active compounds in licorice to target chondrocyte hypertrophy-related proteins. WG showed inhibitory effects against IL-1β-induced chondrocyte hypertrophy by regulating both HDAC4 activation via the PTH1R/PKA/PP2A pathway and the SOX9/β-catenin signaling pathway. In silico analysis demonstrated that 21 active compounds from licorice have binding potential with 11 targets related to chondrocyte hypertrophy. Further molecular docking analysis and in vivo studies elicited four compounds. Based on HPLC, isoliquiritigenin and its precursors were identified and quantified. Taken together, WG is a potential therapeutic agent for chondrocyte hypertrophy-like changes in OA.

2 April 2008 in Phytotherapy Research
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JKJong‐Seob Kil
Jong‐Seob Kil
MKMyung‐Gyou Kim
Myung‐Gyou Kim
HCHye Mi Choi
Hye Mi Choi
JLJong‐Pil Lim
Jong‐Pil Lim
YBYungmin Boo
Yungmin Boo
KLKang Hyun Leem
Kang Hyun Leem

15 October 2012 in Journal of Ginseng Research
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Journal Article
Open access
HBHye-Min Bae
Hye-Min Bae
OCOk-Sun Cho
Ok-Sun Cho
SKShin-Jung Kim
Shin-Jung Kim
BIByung-Ok Im
Byung-Ok Im
SCSoon-Hyun Cho
Soon-Hyun Cho
SKSung Kwon Ko
Sung Kwon Ko
The berry of Panax ginseng significantly inhibited the histamine releases at the concentration of 30 μg/mL (p<0.05) and 10 μg/mL (p<0.01). The ginsenoside Re from ginseng berry was found out to have a potent effect in the experiment of histamin and cytokine release.

Verified
Journal Article
Open access
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YSYun-Soo Seo
Yun-Soo Seo
YKYon-Suk Kim
Yon-Suk Kim
KLKang Hyun Leem
Kang Hyun Leem
Inflammation is an important immune response to pathogen invasion, but excessive inflammation leads to tissue injury and even cytokine storm. Therefore, proper response is needed depending on the intensity of the infection. Ras guanine nucleotide releasing protein 3 (RasGRP3) is a regulator of the TLR-mediated response. In low-intensity inflammation, it negatively regulates production of pro-inflammatory cytokines, especially IL-6. Citri Reticulatae Pericarpium, the peel of Citrus reticulata Blanco, is a major medicinal herb in Korean medicine. The present study aims to investigate whether the Citri Reticulatae Pericarpium extract (CRE) has immunomodulatory activity using the Raw264.7 macrophage. Also, we investigated the effect of CRE on RasGRP3 expression. In the present study, CRE reduced IL-6 production in the low-LPS environment (1 ng/mL) and did not in the high-LPS environment (100 ng/mL). The suppression of IL-6 production in the low-LPS environment (1 ng/mL) was abolished after the pretreatment of RasGRP3 siRNA. The reduced RasGRP3 protein content by 100 ng/mL LPS treatment was increased by CRE treatment. Additionally, nobiletin, a major component of CRE showed a suppressive effect on IL-6 production in the low-LPS environment (1 ng/mL). The present results suggest that CRE alleviates inflammatory response via activating RasGRP3 expression in low-intensity inflammation.