Antitumor effect of the paclitaxel-eluting membrane in a mouse model.

Local treatment of primary bile duct cancer, which grows locally at the primary lesion and seldom metastasizes to distant sites, is challenging. The present study evaluated the antitumor effect, systemic toxicity, biodistribution and survival benefit of the paclitaxel-eluting polyurethane membrane in a tumor model. Membranes containing various amounts of paclitaxel (0, 100, 300, 600 and 1,200 µg/disc) were inserted beneath the tumor mass in mouse models. Tumor size and body weight of the tumor models were monitored for 26 days after insertion of the membrane. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was performed in the tumor tissues. High-performance liquid chromatography was performed for evaluation of paclitaxel concentration in peripheral tissues. Tumor volumes on day 26 of membrane treatment were decreased in a dose-dependent manner. No significant difference in body weight was observed in the groups. A greater number of apoptotic cells were counted per high power field in tumor tissues following an increase of paclitaxel concentration. In the 1,200 µg-group, concentrations of paclitaxel were significantly higher in tumors compared with those of other tissues and serum. The paclitaxel-eluting membrane demonstrated a significant and dose-dependent antitumor activity, and did not exert systemic toxicity in the tumor model.

Design, synthesis and biological evaluation of glutamic acid derivatives as anti-oxidant and anti-inflammatory agents.

A series of glutamic acid derivatives was synthesized and evaluated for their antioxidant activity and stability. We found several potent and stable glutamic acid derivatives. Among them, compound 12b exhibited good in vitro activity, chemical stability and cytotoxicity. A prototype compound 12b showed an anti-inflammatory effect in LPS-stimulated RAW 264.7 cell lines and in a zebrafish model.

Hemostatic action of EGF-endospray on mucosectomy-induced ulcer bleeding animal models.

Gastric bleeding is one of the irritant problems in ulcer patients. In this study, we evaluated hemostatic action of ulcer-coating powder (EGF-endospray) on gastric ulcer animal models. EGF-endospray, containing epidermal growth factor, is designed to be applied through an endoscope. Hemostatic action of the EGF-endospray was evaluated on gastric hemorrhage models of rabbits and micro-pigs. The EGF-endospray was directly applied onto a mucosal resection (MR)-induced gastric bleeding focus in a rabbit model. In a porcine model, the EGF-endospray was applied once via an endoscopy to a bleeding lesion created by endoscopic submucosal dissection. The bleeding focus was then observed via an endoscope. In the rabbit model, EGF-endospray treatment significantly shortened mean bleeding time in comparison with other treatments (104.3 vs 548.0 vs 393.2 s for the EGF-endospray, the non-treated control and the epinephrine injection, respectively). In the micro-pig model, EGF-endospray showed immediate hemostatic action and prolonged covering of the bleeding focus for over 72 h. Histology proved mucosal thickness was more efficiently recovered in all EGF-endospray treated animals. The results of the present study suggest that the EGF-endospray is a promising hemostatic agent for GI bleeding.

Endoscopic application of EGF-chitosan hydrogel for precipitated healing of GI peptic ulcers and mucosectomy-induced ulcers.

The gastrointestinal (GI) endoscopy has become a standard diagnostic tool for GI ulcers and cancer. In this study we studied endoscopic application of epidermal growth factor-containing chitosan hydrogel (EGF-CS gel) for treatment of GI ulcer. We hypothesized that directional ulcer-coating using EGF-CS gel via endoscope would precipitate ulcer-healing. EGF-CS gel was directly introduced to the ulcer-region after ulceration in acetic acid-induced gastric ulcer (AAU) and mucosal resection-induced gastric ulcer (MRU) rabbit and pig models. The ulcer dimensions and mucosal thicknesses were estimated and compared with those in the control group. Healing efficacy was more closely evaluated by microscopic observation of the ulcer after histological assays. In the AAU model, the normalized ulcer size of the gel-treated group was 2.3 times smaller than that in the non-treated control group on day 3 after ulceration (P < 0.01). In the MRU model, the normalized ulcer size of the gel-treated group was 5.4 times smaller compared to that in the non-treated control group on day 1 after ulceration (P < 0.05). Histological analysis supported the ability of EGF-CS gel to heal ulcers. The present study suggests that EGF-CS gel is a promising candidate for treating gastric bleeding and ulcers.

rhEGF-containing thermosensitive and mucoadhesive polymeric sol-gel for endoscopic treatment of gastric ulcer and bleeding.

Gastrointestinal endoscopy is a standard diagnostic tool for gastrointestinal ulcers and cancer. In this study, we have developed recombinant human epidermal growth factor-containing ulcer-coating polymeric sol-gel for endoscopic application. Chitosan and pluronic F127 were employed for their thermoresponsive and bioadhesive properties. At temperatures below 21, polymeric sol-gel remains liquid during endoscopic application and transforms to gel at body temperature after application on ulcers. In an in vitro cellular wounding assay, recombinant human epidermal growth factor sol-gel significantly enhanced the cell migration and decreased the wounding area (68%) compared to nontreated, recombinant human epidermal growth factor solution, and sol-gel without recombinant human epidermal growth factor (42, 49, and 32 % decreased at day 1). The in vivo ulcer-healing study was performed in an acetic acid-induced gastric ulcer rat model and proved that our recombinant human epidermal growth factor endoscopic sol-gel facilitated the ulcer-healing process more efficiently than the other treatments. Ulcer sizes in the recombinant human epidermal growth factor sol-gel group were decreased 2.9- and 2.1-fold compared with those in the nontreated group on days 1 and 3 after ulceration, respectively. The mucosal thickness in the recombinant human epidermal growth factor sol-gel group was significantly increased compared to that in the nontreated group (3.2- and 6.9-fold on days 1 and 3 after ulceration, respectively). In a gastric retention study, recombinant human epidermal growth factor sol-gel stayed on the gastric mucosa more than 2 h after application. The present study suggests that recombinant human epidermal growth factor sol-gel is a prospective candidate for treating gastric ulcers via endoscopic application.

Rabbit gastric ulcer models: comparison and evaluation of acetic acid-induced ulcer and mucosectomy-induced ulcer.

In this study, we examined rabbit gastric ulcer models that can serve as more clinically relevant models. Two types of ulcer model were studied: acetic acid-induced ulcers (AAU) and mucosal resection-induced ulcers (MRU). For AAU, rabbit gastric mucosa was exposed by median laparotomy and treated with bottled acetic acid. MRU was examined as a model for endoscopic mucosal resection (EMR). Normal saline was injected into the submucosal layer and the swollen mucosa was resected with scissors. Endoscopic mucosal resection (EMR) is frequently performed for treatment of early gastric cancers. This procedure inevitably leads to ulcers and bleeding. Bleeding control is the major concern in endoscopic mucosectomy, and some endoscopic hemostatic agents are currently under clinical and preclinical studies. MRU was developed as a model for these induced ulcers and the evaluation of the healing process. The clinical relevancy of those models was compared with that of rat models. Progressive healing was observed for 7 days based on histology. Rabbit models demonstrate round, deep ulcers with clear margins and well-defined healing stages that were difficult to define in rat models.

Multifunctional doxorubicin loaded superparamagnetic iron oxide nanoparticles for chemotherapy and magnetic resonance imaging in liver cancer.

To develop a drug delivery system with enhanced efficacy and minimized adverse effects, we synthesized a novel polymeric nanoparticles, (YCC-DOX) composed of poly (ethylene oxide)-trimellitic anhydride chloride-folate (PEO-TMA-FA), doxorubicin (DOX) and superparamagnetic iron oxide (Fe(3)O(4)) and folate. The efficacy of the nanoparticles was evaluated in rats and rabbits with liver cancer, in comparison with free-DOX (FD) and a commercial liposome drug, DOXIL. YCC-DOX showed the anticancer efficacy and specifically targeted folate receptor (FR)-expressing tumors, thereby increasing the bioavailability and efficacy of DOX. The relative tumor volume of the YCC-DOX group was decreased two- and four-fold compared with the FD and DOXIL groups in the rat and rabbit models, respectively. Furthermore, YCC-DOX showed higher MRI sensitivity comparable to a conventional MRI contrast agent (Resovist), even in its lower iron content. In the immunohistochemical analysis, YCC-DOX group showed the lower expression of CD34 and Ki-67, markers of angiogenesis and cell proliferation, respectively, while apoptotic cells were significantly rich in the YCC-DOX group in terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. These results indicate that YCC-DOX is a promising candidate for treating liver cancer and monitoring the progress of the cancer using MRI.

Overexpression of uncoupling protein 2 in THP1 monocytes inhibits beta2 integrin-mediated firm adhesion and transendothelial migration.

OBJECTIVE: Uncoupling protein 2 (UCP2) belongs to the mitochondrial anion carrier family and regulates production of reactive oxygen species in macrophages. Previous studies have shown that selective genetic disruption of UCP2 in bone marrow cells results in excess accumulation of monocytes/macrophages in the vascular wall of hypercholesterolemic low-density lipoprotein receptor-deficient (LDLR-/-) mice. Here we investigated whether UCP2 regulates expression of genes involved in monocyte recruitment. METHODS AND RESULTS: UCP2 overexpression in THP1 monocytes, which induced a 10-fold increase in mitochondrial UCP2 protein levels, reduced steady-state level of intracellular reactive oxygen species (ROS) and H2O2-induced ROS production. THP1 monocytes with UCP2 overexpression showed lower intracellular calcium levels and less H2O2-triggered intracellular calcium mobilization, and less protein and mRNA levels of beta2 integrins, most notably CD11b. UCP2 overexpression reduced beta2 integrin-mediated firm adhesion of monocytes to either tumor necrosis factor-alpha (TNF-alpha)-stimulated human aortic endothelial cell (HAEC) monolayers or to plates coated with intercellular adhesion molecule-1, not vascular cell adhesion molecule-1. UCP2 overexpression also inhibited cell spreading and actin polymerization in monocytes treated with TNF-alpha and monocyte chemoattractant protein-1 (MCP-1), and reduced MCP-1-induced transmigration of monocytes through HAEC monolayers. CONCLUSIONS: Mitochondrial UCP2 in circulating monocytes may prevent excessive accumulation of monocytes/macrophages in the arterial wall, thereby reducing atherosclerotic plaque formation.