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Yongin si, South Korea

Kim J.W.,Seoul National University | Kim J.-R.,Seoul National University | Yi S.,Seoul National University | Shin K.-H.,Seoul National University | And 7 more authors.
Clinical Therapeutics | Year: 2011

Background: Lobeglitazone, a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist with partial PPAR-α affinity, was developed to treat type 2 diabetes mellitus. Objective: This study's aim was to evaluate the tolerability and pharmacokinetic (PK) properties of lobeglitazone to satisfy regulatory requirements for marketing approval in Korea. Methods: A block-randomized, double-blind, placebo-controlled, single- and multiple-dose study was conducted in healthy subjects. In the pilot study, 4 subjects were administered 0.5 mg, including 1 receiving a placebo. Then, the single-dose study was conducted with 1, 2, 4, and 8 mg doses (8 subjects in each group, including 2 receiving placebos), followed by the multiple-dose study with 1, 2, and 4 mg doses (once daily for 7 days; 8 subjects in each group, including 2 receiving placebos). Serial samples of blood and urine were collected and drug concentrations were determined by high turbulence liquid chromatography-LC/MS/MS. Tolerability assessments were performed throughout the study. Adverse events (AEs) were determined from general health-related questions and self-reports. Results: Thirty-six (mean [SD]; age, 23.6 [2.7] years; weight, 70.0 [6.9] kg) and 25 Korean male subjects (age, 23.5 [3.1] years; weight 69.4 [9.4] kg) were enrolled in the single- and multiple-dose studies, respectively. The data from subjects administered lobeglitazone who completed the study (27, single; 18, multiple) was included in the PK analyses. In the single-dose study, the AUC and C max of lobeglitazone increased with the dose. After repeated dosing for 7 days, the accumulation ratio ranged from 1.1 to 1.4. A total of 25 AEs were reported by 11 (30.6%) and 8 subjects (33.3%) in the single- and multiple-dose studies, respectively. All AEs were mild in intensity and not serious. Conclusions: Lobeglitazone was well tolerated in this small, selected group of healthy male Korean volunteers. The AUC and C max of lobeglitazone increased in a dose-proportional manner from 1 to 4 mg. © 2011 Elsevier HS Journals, Inc.

Lee J.-H.,Seoul National University | Lee J.-H.,Korea Institute of Toxicology | Son J.-H.,Seoul National University | Chae Y.-J.,Chong Kun Dang Research Institute | And 4 more authors.
Biopharmaceutics and Drug Disposition | Year: 2015

The pharmacokinetics of lobeglitazone (LB) was studied after intravenous administration at a dose of 1 mg/kg and oral administration at doses of 0.1, 1 and 10 mg/kg in male and female rats. The area under the plasma concentration-time curve from time zero to infinity (AUCinf) after intravenous administration was approximately 7.1 times higher in female rats than in male rats. In addition, the AUCinf in the case of oral administration was at least 4.4 times higher in female rats and appeared to increase in proportion to the dose in both genders. The in vitro half-lives were 18.8 ± 4.45 min and 60.7 ± 11.2 min, as evidenced by incubating liver microsomes obtained from male and female rats, respectively. As a result, the estimated CLint for LB for male rat liver microsomes (0.0779 ± 0.0233 ml/min/mg protein) was much higher than that for female rat liver microsomes (0.0233 ± 0.0039 ml/min/mg protein, p < 0.05). These observations suggest that there are gender differences in the pharmacokinetics and hepatic metabolism for LB in rats. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Nagarajan S.,Korea Institute of Science and Technology | Nagarajan S.,Korea University | Nagarajan S.,Oregon Health And Science University | Choi M.J.,Korea Institute of Science and Technology | And 11 more authors.
Chemical Biology and Drug Design | Year: 2015

Microtubules are important cellular component that are critical for proper cellular function. Microtubules are synthesized by polymerization of αβ tubulin heterodimers called protofilaments. Microtubule dynamics facilitate proper cell division during mitosis. Disruption of microtubule dynamics by small-molecule agents inhibits mitosis, resulting in apoptotic cell death and preventing cell cycle progression. To identify a novel small molecule that binds the αβ tubulin interface to affect microtubule dynamics, we developed a bioactive conformation alignment pharmacophore (BCAP) model to screen tubulin inhibitors from a huge database. The application of BCAP model generated based on the known αβ-tubulin interface binders enabled us to identify several small-molecules that cause apoptosis in human promyelocytic leukemia (HL-60) cells. Virtual screening combined with an in vitro assay yielded 15 cytotoxic molecules. In particular, ethyl 2-(4-(5-methyl-3-nitro-1H-pyrazol-1-yl)butanamido)-4-phenylthiophene-3-carboxylate (H05) inhibited tubulin polymerization with an IC50 of 17.6 μm concentration. The virtual screening results suggest that the application of an unbiased BCAP pharmacophore greatly eliminates unlikely compounds from a huge database and maximizes screening success. From the limited compounds tested in the tubulin polymerization inhibitor (TPI) assay, compound H05 was discovered as a tubulin inhibitor. This compound requires further structure activity optimization to identify additional potent inhibitors from the same class of molecules. Bioactive conformation alignment pharmacophore (BCAP) model generated based on protein ligand interaction represented at the αβ tubulin heterodimers interface in the left panel. The final hit molecule H05 identified from the BCAP and docking screening shown in the right panel. © 2015 John Wiley & Sons A/S.

Choi M.J.,Korea Institute of Science and Technology | Choi M.J.,Ewha Womans University | No E.S.,Korea Institute of Science and Technology | Thorat D.A.,Korea Institute of Science and Technology | And 15 more authors.
Journal of Medicinal Chemistry | Year: 2013

A series of aryloxazole, thiazole, and isoxazole derivatives was synthesized as vascular-targeting anticancer agents. Antiproliferative activity and tumor vascular-disrupting activity of all of the synthesized compounds were tested in vitro using various human cancer cell lines and HUVECs (human umbilical vein endothelial cells). Several compounds with an arylpiperazinyl oxazole core showed excellent cytotoxicity and metabolic stability in vitro. Among this series, two representative compounds (6-48 and 6-51) were selected and tested for the evaluation of anticancer effects in vivo using tumor-bearing mice. Compound 6-48 effectively reduced tumor growth (42.3% reduction in size) at the dose of 100 mg/kg. We believe that compound 6-48 will serve as a good lead compound for antimitotic and vascular-disrupting agents; further investigation to improve the in vivo efficacy of this series is underway. © 2013 American Chemical Society.

Kim Y.I.,Seoul National University | Kim K.W.,University of Ulsan | Lee H.K.,Seoul National University | Park J.,Seoul National University | And 6 more authors.
Anticancer Research | Year: 2014

Aim: To evaluate the anticancer efficacy of CKD-516, a novel vascular-disrupting agent, alone and in combination with doxorubicin in the treatment of hepatocellular carcinoma (HCC). Materials and Methods: In mice bearing luciferized HCC cells, therapeutic efficacy was assessed for seven days after single administration of CKD-516, doxorubicin, or combination of CKD-516 and doxorubicin. Results: Bioluminescence-imaging (BLI) signals in the CKD-516 group abruptly decreased initially, but recovered at seven days after treatment. BLI signals in the doxorubicin group gradually decreased over the 7-day period. In the combination group, BLI signals were abruptly reduced and remained suppressed for the 7-day period. On histopathological examination, CKD-516-treated tumors showed extensive central necrosis, whereas the peripheral layers remained viable. Doxorubicin-treated tumors showed mild and scattered necrosis. Tumors from the combination group showed more extensive central and peripheral necrosis, with smaller viable peripheral layers than the CKD-516 group. Conclusion: Combination therapy can have additive effects for treatment of HCC compared with CKD-516 or doxorubicin monotherapy.

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