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Anyang, South Korea

Park Y.-J.,Samil Pharmaceutical Co. | Xuan J.J.,Yeungnam University | Oh D.H.,Yeungnam University | Balakrishnan P.,Yeungnam University | And 5 more authors.
Archives of Pharmacal Research | Year: 2010

To develop a novel itraconazole-loaded solid dispersion without crystalline change with improved bioavailability, various itraconazole-loaded solid dispersions were prepared with water, polyvinylpyrroline, poloxamer and citric acid. The effect of carriers on aqueous solubility of itraconazole was investigated. Their physicochemical properties were investigated using SEM, DSC, and powder X-ray diffraction. The dissolution, bioavailability in rats and stability of solid dispersions were evaluated. Unlike conventional solid dispersion system, the itraconazole-loaded solid dispersion with relatively rough surface did not change crystalline form of drug. Our DSC and powder X-ray diffraction results suggested that this solid dispersion was formed by attaching hydrophilic carriers to the surface of drug without crystal change, resulting in conversion of the hydrophobic drug to hydrophilic form. The itraconazole-loaded solid dispersion at the weight ratio of itraconazole/ polyvinylpyrroline/poloxamer of 10/2/0.5 gave maximum drug solubility of about 20 μg/mL. It did not change the crystalline form of drug for at least 6 months, indicating that it was physically stable. It gave higher AUC, C max and T max compared to itraconazole powder and similar values to the commercial product, suggesting that it was bioequivalent to commercial product in rats. Thus, it would be useful to deliver a poorly water-soluble itraconazole without crystalline change with improved bioavailability. © 2010 The Pharmaceutical Society of Korea and Springer Netherlands.

Lee J.S.,Yeungnam University | Park S.-Y.,Yeungnam University | Thapa D.,Yeungnam University | Choi M.K.,Yeungnam University | And 5 more authors.
Experimental and Molecular Medicine | Year: 2010

TNF-α is a major cytokine involved in inflammatory bowel disease (IBD). In this study, water extract of Grifola frondosa (GFW) was evaluated for its protective effects against colon inflammation through the modulation of TNF-α action. In coculture of HT-29 human colon cancer cells with U937 human monocytic cells, TNF-α-induced monocyte adhesion to HT-29 cells was significantly suppressed by GFW (10, 50, 100 μg/ml). The reduced adhesion by GFW correlated with the suppressed expression of MCP-1 and IL-8, the major IBD-associated chemokines. In addition, treatment with GFW significantly suppressed TNF-α-induced reactive oxygen species production and NF-κB transcriptional activity in HT-29 cells. In differentiated U937 monocytic cells, LPS-induced TNF-α production, which is known to be mediated through NF-κB activation, was significantly suppressed by GFW. In an in vivo rat model of IBD, oral administration of GFW for 5 days (1 g/kg per day) significantly inhibited the trinitrobenzene sulfonic acid (TNBS)-induced weight loss, colon ulceration, myeloperoxidase activity, and TNF-α expression in the colon tissue. Moreover, the effect of GFW was similar to that of intra-peritoneal injection of 5-aminosalicylic acid (5-ASA), an active metabolite of sulfasalazine, commonly used drug for the treatment of IBD. The results suggest that GFW ameliorates colon inflammation by suppressing production of TNF-α as well as its signaling through NF-κB leading to the expression of inflammatory chemokines, MCP-1 and IL-8. Taken together, the results strongly suggest GFW is a valuable medicinal food for IBD treatment, and thus may be used as an alternative medicine for IBD.

Seo Y.G.,Yeungnam University | Kim D.-W.,Hanyang University | Yeo W.H.,Yeungnam University | Ramasamy T.,Yeungnam University | And 10 more authors.
Pharmaceutical Research | Year: 2013

Purpose: To investigate the potential of thermosensitive and biadhesive nanomicelles in improving the bioavailability of docetaxel (DCT) and its chemotherapeutic effect. Method: DCT-loaded nanomicelles were prepared by emulsufication and characterized in terms of physico-chemical and visco-elastic parameters. The optimzed formulation was evaluated for in vivo localization, pharmacokinetic and anti-tumor efficacy. Results: The hydrodynamic size of DCT-loaded nanomicelles was approximately 13 nm and the nanomicelles exhibited a sufficient gelation strength (9250 mPa·s) and bioadhesive force (2100 dyn/cm2) to be retained in the upper part of rectum. We observed a high rectal bioavailability of 29% DCT compared to that following oral administration in rats, as it successfully evaded the multidrug efflux transporters and hepatic first-pass metabolism. Plasma concentration around ∼50 ng/mL was maintained throughout the study period (12 h) while Taxotere® attained subtherapeutic range within 4 h of drug administration. Results also revealed that the rectally administered DCT-loaded nanomicelles exhibited a significant anti-tumor effect (200 mm3) with a reduced toxicity profile when compared to orally administered DCT (950 mm3). Furthermore, histological study showed that the rectal mucosa was completely intact with no signs of irritation upon treatment with DCT-loaded nanomicelles. Conclusions: Taken together, our novel thermosensitive and biadhesive nanomicelles demonstrated the ability to improve the bioavailability and chemotherapeutic potential of DCT in vivo. To the best of our knowledge, this is the first report describing the rectal delivery of DCT-loaded nanomicelles. © 2013 Springer Science+Business Media New York.

Samil Pharmaceutical Co. | Date: 1990-08-07


Park Y.-J.,Samil Pharmaceutical Co. | Park Y.S.,Chung - Ang University | Chung Z.C.,Chung - Ang University | Nam Y.S.,Chung - Ang University | And 10 more authors.
Biomolecules and Therapeutics | Year: 2011

The present study was undertaken to determine whether combined treatment with prokinetic trimebutine and mosapride has a synergic effect on gastrointestinal motility and visceral pain associated with gastrointestinal dysfunction. To develop effective gastroprokinetic agents with greater potencies than trimebutine or mosapride for the treatment of gastrointestinal tract disease, a mixture of trimebutine and mosapride was designed and prepared. In the present study, treatment with trimebutine alone showed a dose-dependent effect on propelling movements of normal small and large intestine in mice, whereas mosapride effected only small intestine motility. Co-administration of trimebutine with mosapride, a well-established prokinetic drug, produced a synergistic infl uence on normal small intestine motility, but demonstrated an unclear effect on large intestine motility, with a slight tendency to reduce the propelling time. In a stress model, the small and large intestine motilities were signifi cantly decreased. The reduction of intestine motility was restored to a normal level and the restoring effect was more pronounced in the combined treatment with trimebutine plus mosapride than treatment with trimebutine or mosapride alone. Furthermore, treatment with trimebutine plus mosapride signifi cantly decreased acute visceral pain which was not controlled by trimebutine or mosapride alone. These data suggest that combination therapy with trimebutine plus mosapride has a synergic effect on small and large intestine motility and visceral pain control in gastrointestinal disorders. © 2011 The Korean Society of Applied Pharmacology.

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