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Effects of Ticlopidine on the Pharmacokinetics of Diltiazem and Its Main Metabolite, Desacetyldiltiazem, in Rats

  • Choi, Jun-Shik;Yang, Joon-Seung;Choi, Dong-Hyun
    • Biomolecules & Therapeutics
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    • v.19 no.2
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    • pp.255-260
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    • 2011
  • The purpose of this study was to investigate the effect of ticlopidine on the pharmacokinetics of diltiazem and its active metabolite, desacetyldiltiazem, in rats. Pharmacokinetic parameters of diltiazem and desacetyldiltiazem were determined in rats after oral administration of diltiazem (15 $mg{\cdot}kg^{-1}$) with ticlopidine (3 or 9 $mg{\cdot}kg^{-1}$). The effects of ticlopidine on P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A4 activities were also evaluated. Ticlopidine inhibited CYP3A4 enzyme activity in a concentrationdependent manner with a 50% inhibition concentration ($IC_{50}$) of 35 ${\mu}M$. In addition, ticlopidine did not significantly enhance the cellular accumulation of rhodamine-123 in NCI/ADR-RES cells overexpressing P-gp. Compared with the control (given diltiazem alone), ticlopidine significantly altered the pharmacokinetic parameters of diltiazem. The peak concentration ($C_{max}$) and the area under the plasma concentration-time curve (AUC) of diltiazem were significantly (9 $mg{\cdot}kg^{-1}$, p<0.05) increased in the presence of ticlopidine. The AUC of diltiazem was increased by 1.44-fold in rats in the presence of ticlopidine (9 $mg{\cdot}kg^{-1}$). Consequently, the absolute bioavailability (A.B.) of diltiazem in the presence of ticlopidine (9.3-11.5%) was signifi cantly higher (9 $mg{\cdot}kg^{-1}$, p<0.05) than that in the control group (8.0%). Although ticlopidine significantly (p<0.05) increased the AUC of desacetyldiltiazem, the metabolite-parent AUC ratio (M.R.) in the presence of ticlopidine (9 $mg{\cdot}kg^{-1}$) was significantly decreased compared to that in the control group, implying that ticlopidine could effectively inhibit the metabolism of diltiazem. In conclusion, the concomitant use of ticlopidine significantly enhanced the oral bioavailability of diltiazem in rats by inhibiting CYP3A4-mediated metabolism in the intestine and/or liver rather than by inhibiting intestinal P-gp activity or renal elimination of diltiazem.

Anti-inflammatory Activity of Solvent Fractions from Ginseng Berry Extract in LPS-Induced RAW264.7 Cells (인삼열매추출물의 용매분획물이 LPS로 유도된 RAW264.7 세포에 대한 항염활성)

  • Lee, Ka Soon;Kim, Gwan Hou;Seong, Bong Jae;Kim, Sun Ick;Han, Seung Ho;Lee, Sox Su;Yang, Hui;Yoo, Yung Choon
    • Korean Journal of Medicinal Crop Science
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    • v.22 no.6
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    • pp.449-456
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    • 2014
  • Anti-inflammatory activity of the extracts of ginseng berry (GBE) was investigated through the evaluation of its inhibitory effect on the production of inflammatory meditator, nitric oxide(NO), tumor necrocis factor-alpha (TNF-${\alpha}$), interleukin-6 (IL-6) in LPS-induced RAW264.7 macrophage cells. GBE was fractionated using n-hexane, chloroform, ethylacetate, buthanol and $H_2O$, sequentially. RAW264.7 cells were induced $100ng/m{\ell}$ of lipopolysaccharide (LPS) and treated with 0, 1.6, 8, 40 and $200{\mu}g/m{\ell}$ of GBE fractions. LPS-induced NO production on all of GBE fractions was inhibited with increasing added concentration of GBE fractions. Chloroform fraction of GBE was the most effective in inhibiting LPS-induced TNF-${\alpha}$ production. Hexane, chloroform and $H_2O$ fractions of GBE exhibit strong inhibition LPS-induced IL-6 production. Especially, $H_2O$ fractions of GBE was the most effective in inhibiting LPD-induced IL-6 production without significant cytotoxicity in RAW264.7 cells, and reduced the activation of mitogen-activated protein kinases (MAPK) and IkB phosphorylation. These results indicate that $H_2O$ fractions of GBE exhibits strong anti-inflammatory effects by inhibition of NF-kB by inhibition of p-38 on MAPK and IkB phosphorylation.

Isolation of Bacteria Associated with the King Oyster Mushroom, Pleurotus eryngii

  • Lim, Yun-Jung;Ryu, Jae-San;Shi, Shanliang;Noh, Won;Kim, Eon-Mi;Le, Quy Yang;Lee, Hyun-Sook;Ro, Hyeon-Su
    • Mycobiology
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    • v.36 no.1
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    • pp.13-18
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    • 2008
  • Eight distinct bacteria were isolated form diseased mycelia of the edible mushroom, Pleurotus eryngii. 16S rDNA sequence analysis showed that the isolates belonged to a variety of bacterial genera including Bacillus (LBS5), Enterobacter (LBS1), Sphingomonas (LBS8 and LBS10), Staphylococcus (LBS3, LBS4 and LBS9) and Moraxella (LBS6). Among them, 4 bacterial isolates including LBS1, LBS4, LBS5, and LBS9 evidenced growth inhibitory activity on the mushroom mycelia. The inhibitory activity on the growth of the mushroom fruiting bodies was evaluated by the treatment of the bacterial culture broth or the heat-treated cell-free supernatant of the broth. The treatment of the culture broths or the cell-free supernatants of LBS4 or LBS9 completely inhibited the formation of the fruiting body, thereby suggesting that the inhibitory agent is a heat-stable compound. In the case of LBS5, only the bacterial cell-containing culture broth was capable of inhibiting the formation of the fruiting body, whereas the cell-free supernatant did not, which suggests that an inhibitory agent generated by LBS5 is a protein or a heat-labile chemical compound, potentially a fungal cell wall-degrading enzyme. The culture broth of LBS1 was not inhibitory. However, its cell-free supernatant was capable of inhibiting the formation of fruiting bodies. This indicates that LBS1 may produce an inhibitory heat-stable chemical compound which is readily degraded by its own secreted enzyme.

Isolation and Characterization of the Marine Bacterium, Alteromonas sp. SR-14 Inhibiting the Growth of Diatom, Chaetoceros Species (규조류 Chaetoceros sp. 증식 저해균 Alteromonas sp. SR-14의 분리 및 특성)

  • KIM Ji Hoe;PARK Jeong Heum;SONG Young Hwan;CHANG Dong Suck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.2
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    • pp.155-159
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    • 1999
  • Marine bacteria inhibiting the growth of the diatom, Chaetoceros calcitrans were screened from seawater samples collected at south coast of Korea in 1996. Six strains were isolated from those samples. Among them, a bacterium SR-14 strain had the strongest inhibition activity against the alga. The selected SR-14 strain was identified as an Alteromonas sp. (supposed to be Alteromonas colwelliana) according to its biochemical results. Alteromonas sp. SR-14 was able to grow in raw seawater, aged seawater, Conwy medium for culture of microalgae and C. calcitrans culture filtrate. The host ranges of Alteromonas sp. SR-14 were C. calcitrans, C. muclleri and C. negracile among 10 species of diatom. All of the Chaetoceros spp. tested were inhibited by the Alteromonas sp. SR-14, However, the growth of the other genera in Bacillariophyceae was not inhibited.

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Photoperiod sensing system for timing of flowering in plants

  • Lee, Byoung-Doo;Cha, Joon-Yung;Kim, Mi Ri;Paek, Nam-Chon;Kim, Woe-Yeon
    • BMB Reports
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    • v.51 no.4
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    • pp.163-164
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    • 2018
  • CONSTANS (CO) induces the expression of FLOWERING LOCUS T (FT) in the photoperiodic pathway, and thereby regulates the seasonal timing of flowering. CO expression is induced and CO protein is stabilized by FLAVIN-BINDING KELCH REPEAT F-BOX PROTEIN 1 (FKF1) in the late afternoon, while CO is degraded by CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) during the night. These regulatory cascades were thought to act independently. In our study, we investigated the relationship between FKF1 and COP1 in the regulation of CO stability in response to ambient light conditions. A genetic analysis revealed that FKF1 acts as a direct upstream negative regulator of COP1, in which cop1 mutation is epistatic to fkf1 mutation in the photoperiodic regulation of flowering. COP1 activity requires the formation of a hetero-tetramer with SUPPRESSOR OF PHYA-105 (SPA1), [$(COP1)_2(SPA1)_2$]. Light-activated FKF1 has an increased binding capacity for COP1, forming a FKF1-COP1 hetero-dimer, and inhibiting COP1 homo-dimerization at its coiled-coil (CC) domain. Mutations in the CC domain result in poor COP1 dimerization and misregulation of photoperiodic floral induction. We propose that FKF1 represses COP1 activity by inhibiting COP1 dimerization in the late afternoon under long-day conditions, resulting in early flowering.

Ursodeoxycholic Acid (UDCA) Exerts Anti- Atherogenic Effects by Inhibiting Endoplasmic Reticulum (ER) Stress Induced by Disturbed Flow

  • Chung, Jihwa;Kim, Kyoung Hwa;Lee, Seok Cheol;An, Shung Hyun;Kwon, Kihwan
    • Molecules and Cells
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    • v.38 no.10
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    • pp.851-858
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    • 2015
  • Disturbed blood flow with low-oscillatory shear stress (OSS) is a predominant atherogenic factor leading to dysfunctional endothelial cells (ECs). Recently, it was found that disturbed flow can directly induce endoplasmic reticulum (ER) stress in ECs, thereby playing a critical role in the development and progression of atherosclerosis. Ursodeoxycholic acid (UDCA), a naturally occurring bile acid, has long been used to treat chronic cholestatic liver disease and is known to alleviate endoplasmic reticulum (ER) stress at the cellular level. However, its role in atherosclerosis remains unexplored. In this study, we demonstrated the anti-atherogenic activity of UDCA via inhibition of disturbed flow-induced ER stress in atherosclerosis. UDCA effectively reduced ER stress, resulting in a reduction in expression of X-box binding protein-1 (XBP-1) and CEBP-homologous protein (CHOP) in ECs. UDCA also inhibits the disturbed flow-induced inflammatory responses such as increases in adhesion molecules, monocyte adhesion to ECs, and apoptosis of ECs. In a mouse model of disturbed flow-induced atherosclerosis, UDCA inhibits atheromatous plaque formation through the alleviation of ER stress and a decrease in adhesion molecules. Taken together, our results revealed that UDCA exerts anti-atherogenic activity in disturbed flow-induced atherosclerosis by inhibiting ER stress and the inflammatory response. This study suggests that UDCA may be a therapeutic agent for prevention or treatment of atherosclerosis.

Ethanolic Extract of Pancake Mixture Powder Supplemented with Helianthus tuberosus Enhances Antidiabetic Effects via Inhibiting Inflammatory Mediator NO Production

  • Lee, Kyoung-Dong;Sun, Hyeon-Jin;Lee, Mina;Chun, Jiyeon;Shin, Tai-Sun;Choi, Kap Seong;Shim, Sun-Yup
    • Microbiology and Biotechnology Letters
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    • v.50 no.2
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    • pp.228-234
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    • 2022
  • Helianthus tuberosus is perennial plant as Compositae family and is shown various physiological activities such as analgesic, antipyretic, anti-inflammatory, anti-fungal, anti-spasmodic, aperient, cholagogue, diuretic, spermatogenic, stomachic, and tonic effects. In this study, we investigated the antidiabetic and anti-inflammatory effects of pancake mixture powder (PM) supplemented with H. tuberosus (PMH) in rat skeletal muscle L6 cells and murine macrophage RAW 264.7 cells, respectively. PM and PMH inhibited in vitro α-glucosidase activity. Glucose consumption was increased by PM and PMH without cytotoxicity in rat myoblast L6 cells. Western blot analysis revealed that PM and PMH down-regulated glycogen synthase kinase (GSK)-3β activation in L6 cells. PM and PMH inhibited inflammatory mediator, nitric oxide (NO) production without cytotoxicity in LPS-induced RAW 264.7 cells. The anti-diabetic and anti-inflammatory effects of PMH was more stronger than those of PM. Anti-diabetic and anti-inflammatory effects of PMH would be due to functional characteristics of the supplemented H. tuberosus and the presence of garlic and onion used as ingredients of PM. Taken together, our results that addition of functional materials such as H. tuberosus in product has synergic effects and PMH is potential candidate for treatment of diabetes through inhibiting inflammation.

Purification and Characterization of an Antibacterial Substance from Aerococcus urinaeequi Strain HS36

  • Sung, Ho Sun;Jo, Youl-Lae
    • Journal of Microbiology and Biotechnology
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    • v.30 no.1
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    • pp.93-100
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    • 2020
  • A bacterial strain inhibiting the growth of Vibrio anguillarum, the causative agent of vibriosis, was isolated from fish intestines. The isolated strain HS36 was identified as Aerococcus urinaeequi based on the characteristics of the genus according to Bergey's Manual of Systematic Bacteriology and by 16S rRNA sequencing. The growth rate and antibacterial activity of strain HS36 in shaking culture were higher than those in static culture, while the optimal pH and temperature for antibacterial activity were 7.0 and 30℃, respectively. The active antibacterial substance was purified from a culture broth of A. urinaeequi HS36 by Sephadex G-75 gel chromatography, Sephadex G-25 gel chromatography, and reverse-phase high-performance liquid chromatography. Its molecular weight, as estimated by Tricine SDS-polyacrylamide gel electrophoresis, was approximately 1,000 Da. The antibacterial substance produced by strain HS36 was stable after incubation for 1 h at 100℃. Although its antibacterial activity was optimal at pH 6-8, activity was retained at a pH range from 2 to 11. The purified antibacterial substance was inactivated by proteinase K, papain, and β-amylase treatment. The newly purified antibacterial substance, classified as a class II bacteriocin, inhibited the growth of Klebsiella pneumoniae, Salmonella enterica, and Vibrio alginolyticus.

Idescarpin Isolated from the Fruits of Idesia polycarpa Inhibits Melanin Biosynthesis

  • Baek Seung-Hwa;Kim Dong-Hyun;Lee Chan-Yong;Kho Yung-Hee;Lee Choong-Hwan
    • Journal of Microbiology and Biotechnology
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    • v.16 no.5
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    • pp.667-672
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    • 2006
  • Tyrosinase is an enzyme that catalyzes the biosynthetic pathway of melanin pigments participating in the coloring of skin, hair, and eyes, and is widely distributed in nature. The inhibitory compounds of tyrosinase have been extensively used as a cosmetic agent with a skin-whitening effect. In this paper, several plant extracts were screened using Melan-a cells for the melanin biosynthesis inhibition activity, and Idesia polycarpa was selected. A melanin biosynthesis inhibitor was isolated from I. polycarpa fruits by activity-guided fractionation, and the inhibitor was identified as 6-hydroxy-2-[[[(1-hydroxy-6-oxo-2-cyclohexenl-yl)carbonyl]oxy]methyl]phenyl$\beta$-D-glucopyranoside (idescrapin) by comparing it with reported spectral data. Idescarpin $(IC_{50}=8{\mu}g/ml)$ reduced melanin content compared with the vehicle. In addition, the inhibitory activity of idescarpin for melanin synthesis is mediated by decreasing tyrosinase protein rather than directly inhibiting the tyrosinase activity. These results suggest that idescarpin isolated from I. polycarpa fruits may be used as a skin-whitening agent.

Anti-inflammatory, anti-ulcer and hypoglycaemic activities of ethanolic and crude alkaloid extracts of Madhuca indica (Koenig) Gmelin seed cake

  • M, Seshagiri;RD, Gaikwad;KS, Jyothi;S, Ramchandra;S, Paramjyothi
    • Advances in Traditional Medicine
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    • v.7 no.2
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    • pp.141-149
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    • 2007
  • Madhuca indica has been used ethnomedically in Indian folks. In the present study we have investigated anti-inflammatory, anti-ulcer and hypoglycaemic effect of ethanolic extract (EE) and crude alkaloid extract of Madhuca indica seed cake on albino rats. The study showed that the EE had a significant, dose dependent anti-edematogenic, anti-ulcerogenic and hypoglycaemic activity, whereas the crude alkaloid extract exhibited a significant only. Both the extracts possess dose dependent inhibitory activity on carrageenan-induced edema, inhibiting prostaglandins or mediators involved in prostaglandin synthesis, the second phase of inflammation. The EE was significantly effective in protecting pylorus-ligation-induced gastric ulcers at a higher dose level. The active principle of EE seems to be a selective inhibitor of the COX II (prostaglandin synthesis) without important effect on COX I since, EE exhibited both anti-edematogenic and anti-ulcerogenic effect. The EE was effective in reducing the plasma glucose level in normal albino rats in a dose dependent manner, producing hypoglycaemic effect by stimulating the release of insulin from the ${\beta}-cells$ and/or increasing the uptake of glucose from the plasma.