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Featured researches published by Kyungjin Lee.


European Journal of Pharmacology | 2012

Chlorogenic acid ameliorates brain damage and edema by inhibiting matrix metalloproteinase-2 and 9 in a rat model of focal cerebral ischemia

Kyungjin Lee; Jeong-Sook Lee; Hyeung-Jin Jang; Sung-Moo Kim; Mun Seog Chang; Si Hyung Park; Kwan Su Kim; Jinhyun Bae; Jae-Woo Park; Bumjun Lee; Ho-Young Choi; Chang-Hyun Jeong; Youngmin Bu

Chlorogenic acid (CGA) has been reported to have various beneficial effects on the cardiovascular and central nervous systems. The purpose of the current study was to investigate whether CGA has protective effects against cerebral ischemia and whether these effects are due to modification of brain edema-related vascular factors. In a rat model of transient middle cerebral artery occlusion (MCAo, 2h of occlusion followed by 22 h of reperfusion), we measured infarct volume and performed behavioral test to evaluate the effects of CGA on brain damage and sensory-motor functional deficits. Brain water content and Evans blue extravasation were measured to evaluate brain edema and blood brain barrier (BBB) damage. Lipid peroxidation (LPO) and the expressions and activities of matrix metalloproteinase (MMP)-2 and MMP-9 were measured to investigate the mechanisms of action. Intraperitoneal injection of CGA (3, 10, and 30 mg/kg) at 0 h and 2h after MCAo dose-dependently reduced infarct volume and sensory-motor functional deficits. It also reduced brain water content and Evans blue extravasation. Mechanistically, CGA reduced LPO and MMPs expressions and activities. These results suggest that CGA reduces brain damage, BBB damage and brain edema by radical scavenging activity and the inhibitory effects on MMP-2 and MMP-9.


Journal of Ethnopharmacology | 2011

Inhibitory effects of Chelidonium majus extract on atopic dermatitis-like skin lesions in NC/Nga mice

Gabsik Yang; Kyungjin Lee; Mi-Hwa Lee; So-Hyung Kim; In-Hye Ham; Ho-Young Choi

AIM OF THE STUDY Chelidonium majus (CM) has traditionally been used for treatment of various inflammatory diseases including atopic dermatitis (AD). However its action on atopic dermatitis (AD) is unclear. Therefore, we investigated the effect of CM on AD using NC/Nga mice as an AD model. MATERIALS AND METHODS The effect of CM on 1-chloro-2,4-dinitrobenzene (DNCB) induced NC/Nga mice was evaluated by examining skin symptom severity, itching behavior, ear thickness, levels of serum immunoglobulin E (IgE), tumor necrosis factor-α (TNF-α), and interlukin-4 (IL-4), skin histology. RESULTS The CM significantly reduced the total clinical severity score, itching behavior, ear thickness and the level of serum IgE in AD mouse model. CM not only decreased TNF-α but also IL-4. CONCLUSION These results suggest that CM may be a potential therapeutic modality for AD.


Molecules | 2010

A New 1,4-Diazepine from South China Sea Marine Sponge Callyspongia Species

Riming Huang; Wei Ma; Junde Dong; Xuefeng Zhou; Tunhai Xu; Kyungjin Lee; Xian-Wen Yang; Shi-Hai Xu; Yonghong Liu

A new 1,4-diazepine, callysponine (1), was isolated from a South China Sea Callyspongia sp. marine sponge, together with four known proline-based diketopiperazines: cyclo-(S-Pro-R-Leu) (2), cyclo-(S-Pro-R-Val) (3), cyclo-(S-Pro-R-Ala) (4), and cyclo-(S-Pro-R-Tyr) (5). The new structure was determined on the basis of NMR and MS analysis, and the absolute stereochemistry was defined by NOESY spectroscopy and optical rotation. The structures of the known compounds were identified by comparison of their spectroscopic data with those reported in the literature. Callysponine (1) did not inhibit the growth of HepG2 (hepatoma carcinoma cell), A549 (lung carcinoma cell), and HeLa (cervical cancer cell) cell lines.


Journal of Ethnopharmacology | 2013

Effects of Catalpa ovata stem bark on atopic dermatitis-like skin lesions in NC/Nga mice.

Gabsik Yang; Cheol-Han Choi; Kyungjin Lee; Mi-Hwa Lee; In-Hye Ham; Ho-Young Choi

ETHNOPHARMACOLOGICAL RELEVANCE The stem bark of Catalpa ovata has been used as a traditional herbal medicine for the treatment of various inflammatory diseases such as itching and scabies. AIM OF THE STUDY In the present study, we investigated the anti-AD effects of Catalpa ovata stem bark on Dermatophagoides farinae-induced AD in a NC/Nga mouse AD model. We determined dermatitis score, histology, IgE, cytokines, and chemokines related to hypersensitive immune responses in AD. The mechanism of action was also investigated using HaCaT cells. MATERIALS AND METHODS We investigated the topical effects of Catalpa ovata stem bark on AD-like skin lesions in NC/Nga mice. Five category-experiments were performed, including assessment of dermatitis score; histological analysis of dorsal skin lesions; quantitative measurement of serum total IgE; quantitative measurement of cytokines (IL-1β, IL-4, IL-5, IL-6, IL-13, TNF-α) from dorsal tissue; and RT-PCR analysis of for TSLP and TARC mRNA expression in HaCaT cells. RESULTS The clinical dermatitis score was significantly lower in Catalpa ovata extract (COE) groups than in the control group. Histological analysis showed that COE inhibited hypertrophy and hyperkeratosis of the epidermis, intracellular edema, and reduced the infiltration of inflammatory cells. COE significantly inhibited serum total IgE; Th2 cytokines IL-4, IL-5 and IL-13; pro-inflammatory cytokines IL-1β, IL6 and TNF-α; the Th2 chemokine TARC and the pro-Th2 cytokine TSLP. CONCLUSION These results demonstrate that Catalpa ovata stem bark may be a useful external medicine for treatment of AD. Further investigation is necessary to determine appropriate COE dosage and to evaluate the safety of this medicinal herb.


BMC Complementary and Alternative Medicine | 2012

Inhibition of lipopolysaccharide-induced nitric oxide and prostaglandin E2 production by chloroform fraction of Cudrania tricuspidata in RAW 264.7 macrophages

Gabsik Yang; Kyungjin Lee; Mi-Hwa Lee; In-Hye Ham; Ho-Young Choi

BackgroundCudrania tricuspidata extract is an important traditional herbal remedy for tumors, inflammation, gastritis, and liver damage and is predominantly used in Korea, China, and Japan. However, the anti-inflammatory effects of the extract have not yet been conclusively proved.MethodsIn this study, we investigated the effects of the CHCl3 fraction (CTC) of a methanol extract of C. tricuspidata on the lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production in RAW 264.7 macrophage cells and mouse peritoneal macrophages, and the levels of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in RAW 264.7 macrophage cells.ResultsWe observed that the protein expression levels of inducible NO synthase and COX-2 enzymes were markedly inhibited by CTC in a concentration-dependent manner. In addition, CTC reduced the production of TNF-α, IL-1β, and IL-6 in the LPS-stimulated RAW 264.7 macrophage cells.ConclusionsOur results show that the C. tricuspidata extract could modulate macrophage-mediated inflammatory functions such as the overproduction of cytokines, NO, and PGE2. The CTC was found to be the active fraction in this context.


Chinese Journal of Integrative Medicine | 2013

Therapeutic effects of traditional herbal medicine on cerebral ischemia: A perspective of vascular protection

Youngmin Bu; Kyungjin Lee; Hyuk-Sang Jung; Sang-Kwan Moon

Although many agents for acute ischemic stroke treatment have been developed from extensive preclinical studies, most have failed in clinical trials. As a result, researchers are seeking other methods or agents based on previous studies. Among the various prospective approaches, vascular protection might be the key for development of therapeutic agents for stroke and for improvements in the efficacy and safety of conventional therapies. Traditional medicines in Asian countries are based on clinical experiences and literature accumulated over thousands of years. To date, many studies have used traditional herbal medicines to prove or develop new agents based on stroke treatments mentioned in traditional medicinal theory or other clinical data. In the current review, we describe the vascular factors related to ischemic brain damage and the herbal medicines that impact these factors, including Salviae Miltiorrhizae Radix, Notoginseng Radix, and Curcumae Rhizoma, based on scientific reports and traditional medical theory. Further, we point out the problems associated with herbal medicines in stroke research and propose better methodologies to address these problems.


Toxins | 2015

Analgesic Effects of Bee Venom Derived Phospholipase A2 in a Mouse Model of Oxaliplatin-Induced Neuropathic Pain

Dongxing Li; Younju Lee; Woojin Kim; Kyungjin Lee; Hyunsu Bae; Sun Kwang Kim

A single infusion of oxaliplatin, which is widely used to treat metastatic colorectal cancer, induces specific sensory neurotoxicity signs that are triggered or aggravated when exposed to cold or mechanical stimuli. Bee Venom (BV) has been traditionally used in Korea to treat various pain symptoms. Our recent study demonstrated that BV alleviates oxaliplatin-induced cold allodynia in rats, via noradrenergic and serotonergic analgesic pathways. In this study, we have further investigated whether BV derived phospholipase A2 (bvPLA2) attenuates oxaliplatin-induced cold and mechanical allodynia in mice and its mechanism. The behavioral signs of cold and mechanical allodynia were evaluated by acetone and a von Frey hair test on the hind paw, respectively. The significant allodynia signs were observed from one day after an oxaliplatin injection (6 mg/kg, i.p.). Daily administration of bvPLA2 (0.2 mg/kg, i.p.) for five consecutive days markedly attenuated cold and mechanical allodynia, which was more potent than the effect of BV (1 mg/kg, i.p.). The depletion of noradrenaline by an injection of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP4, 50 mg/kg, i.p.) blocked the analgesic effect of bvPLA2, whereas the depletion of serotonin by injecting DL-p-chlorophenylalanine (PCPA, 150 mg/kg, i.p.) for three successive days did not. Furthermore, idazoxan (α2-adrenegic receptor antagonist, 1 mg/kg, i.p.) completely blocked bvPLA2-induced anti-allodynic action, whereas prazosin (α1-adrenegic antagonist, 10 mg/kg, i.p.) did not. These results suggest that bvPLA2 treatment strongly alleviates oxaliplatin-induced acute cold and mechanical allodynia in mice through the activation of the noradrenergic system, via α2-adrenegic receptors, but not via the serotonergic system.


British Journal of Nutrition | 2013

Prophylactic effects of Lonicera japonica extract on dextran sulphate sodium-induced colitis in a mouse model by the inhibition of the Th1/Th17 response

Jae-Woo Park; Hyunsu Bae; Gihyun Lee; Beom-Gi Hong; Hye Hyun Yoo; Sung-Jig Lim; Kyungjin Lee; Jinsung Kim; Bongha Ryu; Beom-Joon Lee; Jinhyun Bae; Hyejung Lee; Youngmin Bu

Inflammatory bowel diseases (IBD) are chronically relapsing inflammatory disorders of the intestine. Although some therapeutic agents, including steroids, are available for the treatment of IBD, these agents have limited use. Therefore, dietary supplements have emerged as possible interventions for IBD. Japanese honeysuckle flower, the flower of Lonicera japonica, is a well-known dietary supplement and has been used to prevent or treat various inflammatory diseases. In the present study, we investigated the effects of L. japonica on experimental murine colitis. Colitis was induced by 5 % dextran sulphate sodium (DSS) in Balb/c mice. The water extract of L. japonica (LJE) at doses of 20, 100 or 500 mg/kg was orally administered to mice twice per day for 7 d. Body weight, colon length and a histological damage score were assessed to determine the effects on colitis. Cytokine profiles were assessed to examine the effects on helper T (Th) cell-related immunological responses. In addition, CD4⁺CD25⁺Foxp3⁺T cells were analysed in vivo and in vitro for investigating the effects on regulatory T (Treg) cells. LJE showed dose-dependent inhibitory effects against colon shortening, weight loss and histological damage. LJE down-regulated IL-1β, TNF-α, interferon-γ, IL-6, IL-12 and IL-17. However, LJE did not show any significant effects on IL-10, IL-23, transforming growth factor-β1 and Treg cell populations. In conclusion, LJE showed protective effects against DSS-induced colitis via the Th1/Th17 pathway and not via Treg cell-related mechanisms.


Journal of Ethnopharmacology | 2013

The aerial part of Taraxacum coreanum extract has an anti-inflammatory effect on peritoneal macrophages in vitro and increases survival in a mouse model of septic shock

Mi-Hwa Lee; Hee Kang; Kyungjin Lee; Gabsik Yang; In-Hye Ham; Youngmin Bu; Hocheol Kim; Ho-Young Choi

ETHNOPHARMACOLOGICAL RELEVANCE Taraxacum coreanum Nakaiis a dandelion native to Korea and is widely consumed as an edible and medicinal herb. The aerial part of Taraxacum coreanum (TC) has been used therapeutically as a diuretic and anti-inflammatory agent, but its mechanism of action has not yet been evaluated. AIM OF THE STUDY To investigate the anti-inflammatory potential of a Taraxacum coreanum chloroform fraction(TCC) and its mechanisms of action in vitro and in vivo. MATERIALS AND METHODS Isolated mouse peritoneal macrophages were stimulated in vitro with interferon-γ (IFN-γ) and lipopolysaccharide (LPS) in the presence or absence of TCC. The anti-inflammatory effects of TCC were assessed by measuring nitric oxide (NO) and prostaglandin E2 (PGE2) production, as well as expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), IκBα, phospho-IKK, mitogen-activated protein kinases (MAPKs), and signal transducer and activator of transcription (STAT1). The effects of TCC were tested in vivo by measuring cytokine production and survival in a mouse model of lethal septic shock. And the standard compounds of Taraxacum coreanum were analyzed by HPLC using a C18 column. RESULTS Treatment of primary macrophages with TCC in vitro significantly inhibited all of the inflammatory parameters measured, including LPS-induced NO and PGE2 production, iNOS and COX-2 expression, IκBα degradation, IKK phosphorylation, and MAPK and STAT1 activation. In a mouse model of LPS-induced septic shock, TCC inhibited the production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, and increased survival by 83%.Standard compounds (gallic acid, syringic acid) of Taraxacum coreanum were qualified by HPLC analysis. CONCLUSIONS TCC possesses potent anti-inflammatory activity in vitro and in vivo, which occurs at least partly through inhibition of proinflammatory signaling and mediator release. These results strongly support the therapeutic potential of TCC as an anti-inflammatory agent in vivo.


Immunopharmacology and Immunotoxicology | 2012

Effects of Angelica acutiloba on mast cell-mediated allergic reactions in vitro and in vivo.

Kyungjin Lee; Youngjoo Sohn; Min-Jung Lee; Hyun-Sam Cho; Minhee Jang; Na-Young Han; Kyu-Won Shin; Sung-Hoon Kim; Ik-Hyun Cho; Youngmin Bu; Hyuk-Sang Jung

The root of Angelica acutiloba is a widely used herbal medicine which has been used as a typical therapeutic for allergic diseases in traditional medicine. This study was aimed to investigate the effects of A. acutiloba on allergic reactions in in vitro and in vivo models and its mechanism of action. A. acutiloba was extracted by maceration with 80% ethanol (AAE) and standardized by high-performance liquid chromatography. We investigated the effect of AAE on phorbol-12-myristate-13-acetate plus calcium ionophore A23187 (PMACI)-induced cytokine release; phosphorylation of JNK, ERK, and p38 in human mast cell-1 (HMC-1); and compound 48/80-induced release of histamine in rat peritoneal mast cells (RPMCs). We also investigated the effects on Evans blue (EB) extravasation induced by anti-DNP IgE in rats. Treatment with 1, 10 and 100 μg/ml AAE concentration-dependently inhibited the release of cytokines (tumor necrosis factor-α, interleukin (IL) -6, and IL-8) and phosphorylation of ERK and JNK induced by PMACI in HMC-1 cells, but it did not inhibit the phosphorylation of p38. It also inhibited compound 48/80-induced histamine release in RPMCs. Oral administration of 271 mg/kg AAE inhibited EB extravasation in a passive cutaneous anaphylaxis rat model. In conclusion, AAE inhibited mast cell-derived allergic reactions by inhibiting the release of histamine, the production of pro-inflammatory cytokines, and the phosphorylation of ERK and JNK.

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