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Ban JY, Jeon SY, Bae K, Song KS, Seong YH. Catechin and epicatechin from Smilacis chinae rhizome protect cultured rat cortical neurons against amyloid beta protein (25-35)-induced neurotoxicity through inhibition of cytosolic calcium elevation. Life Sci 2006; 79:2251-9. [PMID: 16978655 DOI: 10.1016/j.lfs.2006.07.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2006] [Revised: 06/30/2006] [Accepted: 07/24/2006] [Indexed: 01/23/2023]
Abstract
We previously reported that the Smilacis chinae rhizome inhibits amyloid beta protein (25-35) (Abeta (25-35))-induced neurotoxicity in cultured rat cortical neurons. Here, we isolated catechin and epicatechin from S. chinae rhizome and also studied their neuroprotective effects on Abeta (25-35)-induced neurotoxicity in cultured rat cortical neurons. Catechin and epicatechin inhibited 10 microM Abeta (25-35)-induced neuronal cell death at a concentration of 10 microM, which was measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. Catechin and epicatechin inhibited 10 microM Abeta (25-35)-induced elevation of cytosolic calcium concentration ([Ca2+]c), which was measured by a fluorescent dye, Fluo-4 AM. Catechin and epicatechin also inhibited glutamate release into medium induced by 10 microM Abeta (25-35), which was measured by HPLC, generation of reactive oxygen species (ROS) and activation of caspase-3. These results suggest that catechin and epicatechin prevent Abeta (25-35)-induced neuronal cell damage by interfering with the increase of [Ca2+]c, and then by inhibiting glutamate release, generation of ROS and caspase-3 activity. Furthermore, these effects of catechin and epicatechin may be associated with the neuroprotective effect of the S. chinae rhizome.
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Jin XY, Lee SH, Kim JY, Zhao YZ, Park EJ, Lee BS, Nan JX, Song KS, Ko G, Sohn DH. Polyozellin inhibits nitric oxide production by down-regulating LPS-induced activity of NF-kappaB and SAPK/JNK in RAW 264.7 cells. PLANTA MEDICA 2006; 72:857-9. [PMID: 16783701 DOI: 10.1055/s-2006-946640] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Polyozellin, isolated from Polyozellus multiplex (Thelephoraceae), was investigated for its anti-inflammatory activity in the murine macrophage cell line RAW 264.7. Polyozellin inhibited both lipopolysaccharide (LPS)-induced nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) gene expression in a dose-dependent manner. The effects of polyozellin on the activation of nuclear factor-kappaB (NF-kappaB) and mitogen-activated protein (MAP) kinases in these cells were studied in order to elucidate the underlying mechanism. Polyozellin suppressed the activation of both LPS-induced NF-kappaB and the stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK), but had no effect on the extracellular signal-regulated kinase (ERK) or p38. These data suggest that polyozellin suppresses iNOS expression by inhibiting the activation of NF-kappaB and SAPK/JNK, leading to the inhibition of NO production.
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Ban JY, Cho SO, Koh SB, Song KS, Bae K, Seong YH. Protection of amyloid beta protein (25-35)-induced neurotoxicity by methanol extract of Smilacis chinae rhizome in cultured rat cortical neurons. JOURNAL OF ETHNOPHARMACOLOGY 2006; 106:230-7. [PMID: 16497458 DOI: 10.1016/j.jep.2005.12.034] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Revised: 12/15/2005] [Accepted: 12/29/2005] [Indexed: 05/06/2023]
Abstract
Smilax has various pharmacological effects including antiinflammatory, anticancer and antioxidant activity. The present study aims to investigate the effect of the methanol extract of Smilacis chinae rhizome (SCR) from Smilax china L. (Liliaceae) on amyloid beta protein (Abeta) (25-35), a synthetic 25-35 amyloid peptide, -induced neurotoxicity in cultured rat cerebral cortical neurons. Abeta (25-35) (10 microM) produced a reduction of cell viability, which was significantly reduced by (5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801), an N-methyl-D-aspartate (NMDA) receptor antagonist, verapamil, an L-type Ca2+ channel blocker, and NG-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor. SCR, over a concentration range of 10-50 microg/ml, inhibited 10 microM Abeta (25-35)-induced neuronal cell death, which was measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. SCR (50 microg/ml) inhibited 10 microM Abeta (25-35)-induced elevation of cytosolic calcium concentration ([Ca2+]c), which was measured by a fluorescent dye, Fluo-4 AM. Pretreatment of SCR (10 and 50 microg/ml) also inhibited glutamate release into medium induced by 10 microM Abeta (25-35), which was measured by HPLC, generation of reactive oxygen species and activation of caspase-3. These results suggest that SCR prevents Abeta (25-35)-induced neuronal cell damage in vitro.
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Song KS, Kim YA, Kim HS, Lim JG, Kim HK, Park KI, Park Q. Prevalence of anti-beta(2) glycoprotein-I antibody in patients with primary or secondary immune thrombocytopenia. Platelets 2006; 10:219-22. [PMID: 16801095 DOI: 10.1080/09537109976059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We determined the prevalence of antibodies to beta(2) glycoprotein-I (beta(2) GPI) in sera of 57 patients with primary or secondary immune thrombocytopenia positive for platelet antibody (PAIgG) and in 16 healthy control subjects. Both isotypes (IgG and IgM) of anti-beta(2) GPI were detected by means of semiquantitative ELISA and platelet antibodies were measured by means of flow cytometry using FITC-labeled anti-human IgG. Six (10.5%) of 57 patients with immune thrombocytopenia had anti-beta(2) GPI, whereas none of the 16 healthy subjects had anti-beta(2) GPI. Four were positive for IgM anti-beta(2) GPI, one for IgG anti-beta(2) GPI, and one was positive both for IgM and IgG anti-beta(2) GPI. There was no significant association between the presence of anti-beta(2) GPI and the severity of thrombocytopenia. Our findings suggest that some patients with immune thrombocytopenia have anti-beta(2) GPI in addition to the increased PAIgG; however, the results do not support a major role for anti-beta(2) GPI in the pathogenesis of immune thrombocytopenia.
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Song KS, Kim BS, Choi CR, Lee SM. Association of Br polymorphism of platelet GP Ia gene and immune thrombocytopenic purpura. Platelets 2006; 8:361-5. [PMID: 16793669 DOI: 10.1080/09537109777230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Studies on the molecular structure underlying Br(a)/Br(b) (HPA-5) platelet alloantigen show that a single base polymorphism at position 1648 on platelet mRNA coding for GP Ia results in a amino acid substitution at position 505 on the mature GP Ia which is associated with the two serologically defined Br types. While this polymorphism has no known effects on platelet function, the possible influence of this polymorphism in immune thrombocytopenia ITP is again unexplored. Therefore, the genotype frequency of Br polymorphism in ITP was compared with that of healthy general Korean population. Interestingly, there was a statistical difference (P=0.03) in genotype frequency of Br polymorphism. The association of Br(a)/Br(b) (HPA-5)genotype and occurrence of ITP may suggest the possible influence of genetic polymorphism on the pathogenesis of ITP.
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Thuong PT, Min BS, Jin W, Na M, Lee J, Seong R, Lee YM, Song K, Seong Y, Lee HK, Bae K, Kang SS. Anti-complementary activity of ursane-type triterpenoids from Weigela subsessilis. Biol Pharm Bull 2006; 29:830-3. [PMID: 16595930 DOI: 10.1248/bpb.29.830] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A new ursane-type triterpenoid, weigelic acid (1), and seven known compounds, ursolic acid (2), ilekudinol A (3), corosolic acid (4), ilekudinol B (5), esculentic acid (6), pomolic acid (7), and asiatic acid (8) were isolated from the leaf and stem of Weigela subsessilis. The structure of the new triterpenoid was established as 1beta,2alpha,3alpha,23-tetrahydroxyurs-12-en-28-oic acid on the basis of spectroscopic analyses. In addition, the isolated compounds were evaluated for their anti-complement activity against the classical pathway of the complement system. Of these, compounds 1-2 and 4-8 exhibited anti-complement activity with IC50 values of 152, 90, 130, 51, 56, 4, and 163 microM, respectively, whereas 3 was inactive. This shows that a carboxylic group of ursane-type triterpenoids seems to play an important role in inhibiting the hemolytic activity of human serum against erythrocytes.
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Kim JH, Jeong JH, Jeon ST, Kim H, Ock J, Suk K, Kim SI, Song KS, Lee WH. Decursin Inhibits Induction of Inflammatory Mediators by Blocking Nuclear Factor-κB Activation in Macrophages. Mol Pharmacol 2006; 69:1783-90. [PMID: 16510559 DOI: 10.1124/mol.105.021048] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In the course of screening inhibitors of matrix metalloproteinase (MMP)-9 induction in macrophages, we isolated decursin, a coumarin compound, from the roots of Angelicae gigas. As a marker for the screening and isolation, we tested expression of MMP-9 in RAW264.7 cells and THP-1 cells after treatment with bacterial lipopolysaccharide (LPS), the TLR-4 ligand. Decursin suppressed MMP-9 expression in cells stimulated by LPS in a dose-dependent manner at concentrations below 60 microM with no sign of cytotoxicity. The suppressive effect of decursin was observed not only in cells stimulated with ligands for TLR4, TLR2, TLR3, and TLR9 but also in cells stimulated with interleukin (IL)-1beta, and tumor necrosis factor (TNF)-alpha, indicating that the molecular target of decursin is common signaling molecules induced by these stimulants. In addition to the suppression of MMP-9 expression, decursin blocked nitric oxide production and cytokine (IL-8, MCP-1, IL-1beta, and TNF-alpha) secretion induced by LPS. To find out the molecular mechanism responsible for the suppressive effect of decursin, we analyzed signaling molecules involved in the TLR-mediated activation of MMP-9 and cytokines. Decursin blocked phosphorylation of IkappaB and nuclear translocation of NF-kappaB in THP-1 cells activated with LPS. Furthermore, expression of a luciferase reporter gene under the promoter containing NF-kappaB binding sites was blocked by decursin. These data indicate that decursin is a novel inhibitor of NF-kappaB activation in signaling induced by TLR ligands and cytokines.
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Thuong PT, Jin W, Lee J, Seong R, Lee YM, Seong Y, Song K, Bae K. Inhibitory effect on TNF-alpha-induced IL-8 production in the HT29 cell of constituents from the leaf and stem of Weigela subsessilis. Arch Pharm Res 2005; 28:1135-41. [PMID: 16276968 DOI: 10.1007/bf02972975] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Twelve compounds were isolated from the MeOH extract of the leaf and stem of the Korean endemic plant Weigela subsessilis L. H. Bailey. Their chemical structures were elucidated on the basis of physicochemical and spectroscopic data and by comparison with those of published literatures. These compounds were identified as three sterols, beta-sitosterol acetate (2), betasitosterol (3), daucosterol (11), eight triterpenoids, squalene (1), ursolic acid (4), ilekudinol A (5), corosolic acid (6), ilekudinol B (7), esculentic acid (8), pomolic acid (9), asiatic acid (10), and one iridoid glycoside, alboside I (12). This is the first report pertaining to the isolation of these compounds from Weigela subsessilis L. H. Bailey. In addition, three compounds 7, 9, and 12 were found to display a strong inhibitory effect on the production of IL-8 in the HT29 cells stimulated by TNF-alpha.
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Kwak HM, Jeon SY, Sohng BH, Kim JG, Lee JM, Lee KB, Jeong HH, Hur JM, Kang YH, Song KS. β-Secretase(BACE1) inhibitors from pomegranate (Punica granatum) husk. Arch Pharm Res 2005; 28:1328-32. [PMID: 16392663 DOI: 10.1007/bf02977896] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
In the course of screening for anti-dementia agents from natural products, two beta-secretase (BACE1) inhibitors were isolated from the husk of pomegranate (Punica granatum) by activity-guided purification. They were identified as ellagic acid and punicalagin with IC50 values of 3.9 x10(-6) and 4.1x10(-7) M and Ki values of 2.4x10(-5) and 5.9x10(-7) M, respectively. The compounds were non-competitive inhibitors with a substrate in the Dixon plot. Ellagic acid and punicalagin were less inhibitory to alpha-secretase (TACE) and other serine proteases such as chymotrypsin, trypsin, and elastase, thus indicating that they were relatively specific inhibitors of BACE1.
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Song KS. High incidence of plasma factor XII deficiency in normal Korean subjects. Thromb Res 2005; 117:732-3. [PMID: 16165195 DOI: 10.1016/j.thromres.2005.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Revised: 07/22/2005] [Accepted: 08/02/2005] [Indexed: 11/23/2022]
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Song KS, Kim HKW. Regeneration of the proximal tibial epiphysis after infantile osteomyelitis. ACTA ACUST UNITED AC 2005; 87:979-83. [PMID: 15972915 DOI: 10.1302/0301-620x.87b7.16027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We reviewed three infants with destructive osteomyelitis involving the proximal tibial epiphysis at a follow-up of eight to 22 years. All cases showed early radiographic destructive changes in the medial or lateral aspects of the epiphysis and metaphysis. Despite the ominous early appearance of the epiphysis, all cases showed spontaneous re-ossification of the epiphysis with restoration of the tibial condyle and preservation of joint congruity. The patients, however, developed a valgus or varus deformity which was treated satisfactorily with one to three proximal tibial osteotomies. The potential for regeneration of the epiphysis following infantile osteomyelitis of the proximal tibia suggests these cases should be treated expectantly with regard to joint congruity.
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Lee HJ, Seong YH, Bae KH, Kwon SH, Kwak HM, Nho SK, Kim KA, Hur JM, Lee KB, Kang YH, Song KS. β-Secretase (BACE1) inhibitors from Sanguisorbae Radix. Arch Pharm Res 2005; 28:799-803. [PMID: 16114494 DOI: 10.1007/bf02977345] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the course of screening anti-dementia agents from natural products, two beta-secretase (BACE1) inhibitors were isolated from the ethyl acetate soluble fraction of Sanguisorbae Radix by the activity-guided purification using silica gel, Sephadex LH-20, and RP-HPLC. They were identified as 1,2,3-trigalloyl-4,6-hexahydroxydiphenoyl-beta-D-glucopyranoside (Tellimagrandin II, 1) and 1,2,3,4,6-pentagalloyl-beta-D-glucopyranoside (2) and were shown to non-competitively inhibit beta-secretase (BACE1) with the IC50 values of 3.10x10(-6) M and 3.76x10(-6) M, respectively. The Ki values of 1 and 2 were 6.84x10(-6) M and 5.13x10(-6) M. They were less inhibitory to alphasecretase (TACE) and other serine proteases such as chymotrypsin, trypsin, and elastase, suggesting that they were relatively specific inhibitors of BACE1.
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Sohn JH, Song JW, Seo JB, Do KH, Lee JS, Kim DK, Song KS, Lim TH. Case report: pericardial rupture and cardiac herniation after blunt trauma: a case diagnosed using cardiac MRI. Br J Radiol 2005; 78:447-9. [PMID: 15845942 DOI: 10.1259/bjr/31146905] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Pericardial rupture following blunt chest trauma is rare, and is not usually diagnosed pre-operatively. If pericardial rupture is not recognized and treated promptly, it may be fatal owing to cardiac herniation. We report a case of traumatic herniation of the heart for which a CT scan and MRI made a major contribution to the diagnosis.
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Kim GS, Kim HT, Seong JD, Oh SR, Lee CO, Bang JK, Seong NS, Song KS. Cytotoxic steroidal saponins from the rhizomes of Asparagus oligoclonos. JOURNAL OF NATURAL PRODUCTS 2005; 68:766-8. [PMID: 15921426 DOI: 10.1021/np040128k] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Two new steroidal saponins, aspaoligonins A (2) and B (3), were isolated from the methanolic extract of the rhizomes of Asparagus oligoclonos together with a known spirostanol saponin, asparanin A (1). Aspaoligonins A and B were characterized as (25S*)-5beta-spirostan-3beta,17alpha-diol 3-O-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranoside and (25S*)-5beta-spirostan-3beta,17alpha-diol 3-O-alpha-L-rhamnopyanosyl (1-->4)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-glucopyranoside, respectively, by spectrometric analyses including HRFABMS and 2D NMR. Compounds 1-3 were cytotoxic against five human tumor cell lines with IC50 values of 2.05-2.84 microg/mL.
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Lee BS, Kim SM, Seong JK, Kim SH, Jeong HY, Lee HY, Song KS, Kang DY, Noh SM, Shin KS, Cho JS. Phlegmonous gastritis after endoscopic mucosal resection. Endoscopy 2005; 37:490-3. [PMID: 15844031 DOI: 10.1055/s-2005-861254] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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91
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Park IH, Chung SK, Lee KB, Yoo YC, Kim SK, Kim GS, Song KS. An antioxidant hispidin from the mycelial cultures of Phellinus linteus. Arch Pharm Res 2005; 27:615-8. [PMID: 15283462 DOI: 10.1007/bf02980159] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the course of screening for reactive oxygen species scavengers from natural products, an antioxidant was isolated from the mycelial culture broth of Phellinus linteus and identified as hispidin. The hispidin content was reached its maximum level at 12 days after onset of inoculation. About 2.5 mg/mL of hispidin was produced by P. linteus in a yeast-malt medium (pH 5.8, 25 degrees C). Hispidin inhibited 22.6 and 56.8% of the super oxide anion radical, 79.4 and 95.3% of the hydroxyl radical, and 28.1 and 85.5% of the DPPH radical at 0.1 and 1.0 mM, respectively. The positive control alpha-tocopherol scavenged 25.6 and 60.3%, 74.6 and 96.3%, and 32.7 and 77.5% of each radical, respectively, at the same concentrations. However, hispidin showed no significant activity on the hydrogen peroxide radical.
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Park HJ, Song KS, Nah BM, Choi JR, Kim MJ. Homozygous type I Protein C deficiency in neonatal purpura fulminans with a novel frame-shift deletion of 10 base pairs in exon 8 of PROC gene. J Thromb Haemost 2005; 3:593-5. [PMID: 15748260 DOI: 10.1111/j.1538-7836.2005.01144.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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93
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Chung SK, Nam JA, Jeon SY, Kim SI, Lee HJ, Chung TH, Song KS. A prolyl endopeptidase-inhibiting antioxidant from Phyllanthus ussurensis. Arch Pharm Res 2004; 26:1024-8. [PMID: 14723335 DOI: 10.1007/bf02994753] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A prolyl endopeptidase inhibitor was isolated from the ethyl acetate soluble fraction of Phyllanthus ussurensis. The active compound was identified as an ellagitannin, corilagin. It was shown to non-competitively inhibit prolyl endopeptidase (PEP) with the IC50 value of 1.17x10(-6) microM. The Ki value was 6.70x10(-7) M. Corilagin was less inhibitory to other serine proteases such as chymotrypsin, trypsin, and elastase, indicating that it was relatively a specific inhibitor of PEP. Corilagin also effectively inhibited reactive oxygen species such as hydroxide and superoxide anion radical, hydrogen peroxide, and DPPH. Especially, corilagin showed potent scavenging activity on the superoxide anion radical in the ESR method (IC50 = 3.79x10(-6) M) as well as xanthine oxidase system.
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Jeon SY, Bae K, Seong YH, Song KS. Green tea catechins as a BACE1 (beta-secretase) inhibitor. Bioorg Med Chem Lett 2004; 13:3905-8. [PMID: 14592472 DOI: 10.1016/j.bmcl.2003.09.018] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the course of searching for BACE1 (beta-secretase) inhibitors from natural products, the ethyl acetate soluble fraction of green tea, which was suspected to be rich in catechin content, showed potent inhibitory activity. (-)-Epigallocatechin gallate, (-)-epicatechin gallate, and (-)-gallocatechin gallate were isolated with IC(50) values of 1.6 x 10(-6), 4.5 x 10(-6), and 1.8 x 10(-6) M, respectively. Seven additional authentic catechins were tested for a fundamental structure-activity relationship. (-)-Catechin gallate, (-)-gallocatechin, and (-)-epigallocatechin significantly inhibited BACE1 activity with IC(50) values of 6.0 x 10(-6), 2.5 x 10(-6), and 2.4 x 10(-6) M, respectively. However, (+)-catechin, (-)-catechin, (+)-epicatechin, and (-)-epicatechin exhibited about ten times less inhibitory activity. The stronger activity seemed to be related to the pyrogallol moiety on C-2 and/or C-3 of catechin skeleton, while the stereochemistry of C-2 and C-3 did not have an effect on the inhibitory activity. The active catechins inhibited BACE1 activity in a non-competitive manner with a substrate in Dixon plots.
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95
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Joo GJ, Kim YM, Lee IJ, Song KS, Rhee IK. Growth promotion of red pepper plug seedlings and the production of gibberellins by Bacillus cereus, Bacillus macroides and Bacillus pumilus. Biotechnol Lett 2004; 26:487-91. [PMID: 15127789 DOI: 10.1023/b:bile.0000019555.87121.34] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The growth of red pepper plug seedlings was promoted by Bacillus cereus MJ-1, B. macroides CJ-29, and B. pumilus CJ-69 isolated from the rhizosphere. Gibberellins (GAs), a well-known plant growth-promoting hormone, were detected in the culture broth of their rhizobacteria. Among the GAs, the contents of GA1, GA3, GA4, and GA7, physiologically active GAs, were comparatively higher than those of others, suggesting that the growth promoting effect was originated from the GAs. This isthe first report on the production of GA5, GA8, GA34, GA44, and GA53 by bacteria.
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Kim JH, Lee JS, Song KS, Kwon CS, Kim YK, Kim JS. Polyozellin isolated from Polyozellus multiplex induces phase 2 enzymes in mouse hepatoma cells and differentiation in human myeloid leukaemic cell lines. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2004; 52:451-455. [PMID: 14759131 DOI: 10.1021/jf034748n] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Induction of cellular phase 2 detoxifying enzymes is associated with cancer preventive potential. Quinone reductase (QR) has been used as a prototype for anticarcinogenic phase 2 enzymes because of its widespread distribution in mammalian systems, large amplitude of inducer response, and ease of measurement in murine hepatoma cells. Methanol extract of Polyozellus multiplex, which shows a strong QR induction potential, was subjected to bioassay-guided fractionation, and polyozellin (PM1) appeared to be a major active component. In in vitro cultured cells (hepa1c1c7 and BPRc1 cells), polyozellin enhanced QR, glutathione S-transferase (GST) activities, and glutathione (GSH) content in a dose-dependent manner. The compound also significantly promoted differentiation of HL-60 human promyelocytic emia cells. In conclusion, polyozellin deserves further in vivo study to evaluate its potential as a cancer preventive agent.
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Park IH, Jeon SY, Lee HJ, Kim SI, Song KS. A beta-secretase (BACE1) inhibitor hispidin from the mycelial cultures of Phellinus linteus. PLANTA MEDICA 2004; 70:143-146. [PMID: 14994192 DOI: 10.1055/s-2004-815491] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In the course of screening for anti-dementia agents from natural products, a beta-secretase (BACE1) inhibitor was isolated from the culture broth of Phellinus linteus and identified as hispidin. It showed an IC (50) value of 4.9 x 10 (-6) M and a Ki value of 8.4 x 10 (-6) M. The compound was a non-competitive inhibitor. Hispidin also inhibited a prolyl endopeptidase (IC (50) = 1.6 x 10 (-5) M, Ki = 2.4 x 10 (-5) M), but it was less inhibitory to alpha-secretase (TACE) and other serine proteases such as chymotrypsin, trypsin, and elastase.
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Lee CH, Kim SI, Lee KB, Yoo YC, Ryu SY, Song KS. Neuraminidase inhibitors from Reynoutria elliptica. Arch Pharm Res 2003; 26:367-74. [PMID: 12785732 DOI: 10.1007/bf02976693] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In the course of screening neuraminidase inhibitors from herbal medicines, Reynoutria elliptica exhibited high inhibitory activity. Four active compounds were isolated from the ethyl acetate soluble fraction by consecutive purification using sillica gel, Sephadex LH-20 chromatography, and recrystallization. The chemical structures of these compounds were identified as 1,3,8-trihydroxy-6-methylanthraquinone (emodin) 1,8-dihydroxy-3-methoxy-6-methylanthraquinone (emodin 3-methyl ether; physcion), 1,3,8-trihydroxy-6-hydoxymethylanthraquinone (omega-hydroxyemodin), and 3,5,4'-trihydroxystilbene (trans-resvertrol) by spectral data including MS, 1H-, and 13C-NMR. The IC50 values of emodin, emodin 3-methyl ether, omega-hydroxyemodin, and trans-resvertrol were 2.81, 74.07, 10.49, and 8.77 microM, respectively. They did not inhibit other glycosidase such as glucosidase, mannosidase, and galactosidase, indicating that they were relatively specific inhibitors of neuraminidase.
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Kim HK, Song KS, Park YS, Kang YH, Lee YJ, Lee KR, Kim HK, Ryu KW, Bae JM, Kim S. Elevated levels of circulating platelet microparticles, VEGF, IL-6 and RANTES in patients with gastric cancer: possible role of a metastasis predictor. Eur J Cancer 2003; 39:184-91. [PMID: 12509950 DOI: 10.1016/s0959-8049(02)00596-8] [Citation(s) in RCA: 310] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The activation of coagulation, angiogenesis and inflammatory cytokines are considered to be related with tumour growth and metastasis. We investigated the plasma levels of platelet microparticles (PMP), vascular endothelial growth factor (VEGF), IL-6, and the chemokine RANTES in patients with gastric cancer (n=109) and in healthy controls (n=29). The plasma levels of PMP, IL-6 and RANTES were significantly higher in the patients than in the healthy controls, and plasma levels of PMP, VEGF, IL-6 and RANTES were significantly higher in patients with stage IV disease than those in patients with stage I or stage II/III. In terms of predicting distant metastasis, the sensitivities of PMP, VEGF, IL-6 and RANTES were 93.3%, 56.7%, 70.0% and 81.8%, respectively, and the corresponding specificities were 91.1%, 64.6%, 79.7% and 50.0%. Among these parameters, PMP had the highest diagnostic accuracy. Significant correlations were found between PMP, VEGF, IL-6 and RANTES. This study demonstrates that the plasma levels of PMP, VEGF, IL-6 and RANTES were markedly increased in patients with stage IV disease, and that these increased plasma levels of IL-6, RANTES, and especially PMP, might be useful for identifying metastatic gastric patients.
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Kim HK, Song KS, Lee ES, Lee YJ, Park YS, Lee KR, Lee SN. Optimized flow cytometric assay for the measurement of platelet microparticles in plasma: pre-analytic and analytic considerations. Blood Coagul Fibrinolysis 2002; 13:393-7. [PMID: 12138366 DOI: 10.1097/00001721-200207000-00003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Platelet microparticles (PMP) are submicroscopic membrane vesicles released by platelets during activation. Flow cytometry is the most widely used method for quantifying PMP, but the optimization of the technical method has not yet been fully evaluated. This study was designed to assess the pre-analytical variables including blood sampling conditions, and to evaluate the analytical variations including effect of the platelet-specific antibodies and quantitative beads, precision, linearity and accuracy in comparison with beta-thromboglobulin, which is one of the platelet activation markers. Numbers of PMP collected into citrate-theophylline-adenosine-dipyridamole (CTAD) tubes were increased with time, but to a lesser extent than when collected into sodium citrate tubes. The precision of the PMP assay was relatively high. Excellent linear correlation was observed for dilution linearity. Regarding the platelet-specific antibodies used, anti-CD41a-labeled samples resulted in higher PMP levels than those labeled with anti-CD61 and anti-CD42a. There was no significant difference of PMP counts according to the quantitative beads. The PMP assay is well correlated with beta-thromboglobulin levels. Our findings suggest that blood samples for the PMP assay should be collected in a CTAD tube and delayed measurement is not allowed to avoid artefactual platelet activation. The PMP assay can be used successfully as a useful marker of the detection of in vivo platelet activation, provided that pre-analytical and technical points are optimally taken into consideration.
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