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Purpose: To overcome definite limitations of angiogenesis inhibitors such as insufficient therapeutic efficacy as a single drug and resisting or conflicting effect under chronic treatment, it is required to develop a new regimen to improve the therapeutic effect., Methods: The combination effect of a multi-targeting angiogenesis inhibitor (LHT7) and a selective cyclooxygenase-2 inhibitor (celecoxib) on neovascularization in tumor growth was studied both in vitro and vivo experiments., Results: While hypoxia-mediated COX-2 overexpression and macrophage recruitment were observed at LHT7-treated tumor tissues, it was well-controlled by the combination of celecoxib and LHT7. On the other hand, the in vitro tube formation and the in vivo tumor vessel formation and structure were inhibited by either LHT7 or celecoxib, but the inhibition effect was further enhanced by using them together. However, the combination therapy did not further enhance the inhibitory effect on tumor growth in terms of volume compared to single drug uses, which attributed not to increased cellular apoptosis but to decreased cell proliferation., Conclusions: COX-2 inhibition could enhance the therapeutic effect of anti-angiogenic drugs both by inhibiting the inflammatory reactions induced by hypoxia and by altering the vascular stabilization that is mediated by an assembly with mural cells.

Purpose: The purpose of this study was to investigate the effect of locally delivered pancreatic islet with liposomal clodronate (Clodrosome®) as an immunoprotection agent for the treatment of type 1 diabetes., Method: The bio-distribution of liposomal clodronate in matrigel was checked by imaging analyzer. To verify the therapeutic efficacy of locally delivered islet with liposomal clodronate using injectable hydrogel, four groups of islet transplanted mice (n = 6 in each group) were prepared: 1) the islet group, 2) the islet-Clodrosome group, 3) the islet-Matrigel group, and 4) the islet-Matrigel-Clodrosome group. Immune cell migration and activation, and pro-inflammatory cytokine secretion was evaluated by immunohistochemistry staining and ELISA assay., Results: Cy5.5 labeled liposomes remained in the matrigel for over 7 days. The median survival time of transplanted islets (Islet-Matrigel-Clodrosome group) was significantly increased (>60 days), compared to other groups. Locally delivered liposomal clodronate in matrigel effectively inhibited the activation of macrophages, immune cell migration and activation, and pro-inflammatory cytokine secretion from macrophages., Conclusions: Locally co-delivered pancreatic islets and liposomal clodronate using injectable hydrogel effectively cured type 1 diabetes. Especially, the inhibition of macrophage attack in the early stage after local delivery of islets was very important for the successful long-term survival of delivered islets.

Androgen-disrupting chemicals (ADCs) can alter male sexual development. Although the effects of ADCs on hormone disruption have been studied, their influence on the immune response is not fully understood. To investigate the effects of ADCs on innate immunity, we tested eight candidate ADCs for their influence on macrophages by measuring nitric oxide (NO) production and cell viability. Our results showed that treatment with a mixture of lipopolysaccharide and hexachlorobenzene increased NO production in RAW 264.7 cells, a murine macrophage cell line. In contrast, compared to exposure to a negative control, exposure to di-2-ethylhexyl adipate (DEHA), benzylbutyl phthalate (BBP), testosterone (TTT), or permethrin decreased NO production. DEHA, BBP, and TTT inhibited NO production in an inducible nitric oxide synthase-dependent manner. Treatment with bisphenol A (BPA), nonylphenol (NNP), or tributyltin chloride (TBTC) reduced NO production and induced cell death. While BPA induced RAW 264.7 cell death through apoptosis, NNP and TBTC caused cell death through necrosis. These results offer insights into the influences of ADCs on the innate immune system.

Single-walled carbon nanotubes (SWCNTs) are potent nanomaterials that have diverse shapes and features. The utilization of these molecules for drug delivery is being investigated; thus, it is important to determine whether they alter immune responses against pathogens. In this study, we show that macrophages treated with a mixture of lipopolysaccharide and SWCNTs produced normal levels of nitric oxide and inducible nitric oxide synthase mRNA. However, these treatments induced cell death, presumably via necrosis. In addition, treating cells with SWCNTs induced the expression of tumor necrosis factor-α mRNA, a potent pro-inflammatory cytokine. These results suggest that SWCNTs may influence immune responses, which could result in unexpected effects following their administration for the purpose of drug delivery.

Purpose: Since the absorption of ceftriaxone (CTO) in the intestine is restricted by its natural physiological characteristics, we developed a series of small synthetic compounds derived from bile acids to promote the absorption of CTO in the gastrointestinal tract., Methods: Several bile acid derivatives were screened by measuring water solubility and partition coefficient of their complexes with CTO. The pharmacokinetic parameters of the selected CTO/HDCK ionic complex in monkeys were evaluated. The absorption pathway of CTO/HDCK complex was evaluated using Caco-2 cells and MDCK cells transfected with ASBT gene., Results: HDCK enhanced the apparent membrane permeability of CTO 5.8-fold in the parallel artificial membrane permeability assay model. CTO/HDCK complex permeated Caco-2 cell via transcellular pathway, and interaction of the HDCK complex with ASBT was important to enhance uptake. When CTO/HDCK (equivalent to 50 mg/kg of ceftriaxone) formulated with lactose, poloxamer 407 and Labrasol was orally administered to monkeys, its maximum plasma concentration was 19.5 ± 1.8 μg/ml and oral bioavailability 28.5 ± 3.1%., Conclusions: The CTO/HDCK formulation could enhance oral bioavailability of CTO in non-human primates. This oral formulation could be an alternative to injectable CTO with enhanced clinical effects.

Purpose: Orally absorbable anticancer medications have great advantages for conventional cancer therapies to patients. Here we evaluated the potent anticancer effect of orally absorbable LHD, a chemical conjugate of low-molecular-weight heparin and deoxycholic acid, on tumor graft growth models., Methods: We characterized the angiogenic factors, such as VEGF, heparanase, and MMPs, of murine squamous cell carcinoma (SCC7), melanoma (B16F10) or lung carcinoma (LLC1). Two weeks after oral administration of LHD into these cancer-cell-bearing mice, we evaluated the antiangiogenic activity of LHD., Results: Although all cancer cells expressed the angiogenic factors, SCC7 cells had much higher angiogenic potential and grew rapidly after implantation into mice. When orally administered, LHD delayed tumor graft growth regardless of cancer types. Particularly, LHD powerfully diminished the SCC7-derived tumor growth. Also, the expression of angiogenic factors in all kinds of tumor tissues was decreased, thereby attenuating the neovascularization in tumor tissue., Conclusion: Our study shows that LHD has potent anticancer and antiangiogenic effect on at least three kinds of tumor cells. LHD can be specifically used for preventing neovascularization in tumor tissue because it has therapeutical potential as an antiangiogenic drug and can be orally absorbed.

Purpose: We prepared tumor endothelium targeted cRGD-modified heparin derivative (cRGD-HL) by coupling heparin-lithocholic acid (HL) with cRGDyK, and evaluated inhibition effects of cRGD-HL on angiogenesis and tumor growth., Methods: To evaluate antiangiogenic activity of cRGD-HL, we performed tests on endothelial cell adhesion and migration to vitronectin, tube formation, binding affinity to purified alpha(v)beta(3) integrin, and in vivo Matrigel plug assay. The antitumor activity of cRGD-HL was also evaluated by monitoring tumor growth and microvessel formation in squamous cell carcinoma (SCC7) tumor., Results: The cRGD-HL significantly inhibited adhesion and migration of endothelial cells to vitronectin, and tubular structures of endothelial cells. Compared to cRGDyK and HL, cRGD-HL has high binding affinity to purified alpha(v)beta(3) integrin. The enhanced antiangiogenic effect of cRGD-HL was confirmed in Matrigel assay by showing the significant inhibition of bFGF-driven angiogenesis and blood vessel formation. It was thought that potent antiangiogenic effect of cRGD-HL was probably due to the interference of alpha(v)beta(3)-mediated interaction, resulting in the enhanced antitumoral activity against SCC7 tumor., Conclusion: These results demonstrated that cRGD-modified heparin derivative enhanced anti-angiotherapeutic effects against solid tumor, and therefore, it could be applied to treat various cancers and angiogenic diseases as a potent angiogenesis inhibitor.

Purpose: Our previous study confirmed that heparin-deoxycholic acid conjugate (HD) had a potent antiangiogenic effect and safety to use for long-term treatment. Herein, the combined therapeutic effect of HD and doxorubicin (DOX) was evaluated against squamous cell carcinoma (SCC7) and B16F10 melanoma., Methods: The inhibitory effect of cell proliferation and cellular uptake of HD was studied in SCC7 and B16F10. The combination effects of HD and DOX were evaluated by measuring cytotoxicity and apoptosis as well as tumor growth and apoptosis in vivo against SCC7 and B16F10 tumor-bearing mice., Results: HD displayed potent inhibitory effect on SCC7 and B16F10 cell proliferation, but it showed a low cytotoxic effect. Concurrent treatment of HD and DOX displayed enhanced cytotoxic effects and apoptosis on SCC7 and B16F10. The cellular uptake of HD and DOX was affected by the collective cytotoxic effects of these two drugs: each drug suppressed the tumor growth, and their combined treatment enhanced apoptosis and collectively inhibited the tumor growth of SCC7 and B16F10 in vivo., Conclusion: These results demonstrated that HD with cytostatic and antiangiogenetic activities, enhanced the antitumor activity of DOX against SCC7 and B16F10, and the combined treatment of these two drugs might have enhanced therapeutic efficacy.

Purpose: Anitangiogenic and apoptotic properties of a novel chemically modified heparin derivative with low anticoagulant activity were evaluated on the experimental in vitro and in vivo model., Materials and Methods: Heparin-lithocholate conjugate (HL) was initially synthesized by covalently bonding lithocholate to heparin. Folate-HL conjugate (FHL) was further synthesized by conjugating folate to HL. Antiangiogenic and apoptotic abilities of HL and FHL were characterized in vitro and in vivo experimentations., Results: Compared to unmodified heparin, both HL and FHL represented a low anticoagulant activity (38 and 28%, respectively). HL and FHL maintained antiangiogenic activity even further modification from the results of Matrigel plugs assay. FHL specifically induced apoptosis on KB cells having highly expressed folate receptor after cellular internalization. Both administered HL and FHL had similar antiangiogenic activity and inhibitory effect on tumor growth in vivo although FHL induced higher apoptosis on tumor tissues., Conclusions: In vivo tumor growth inhibition was possibly due to the decrease of vessel density and apoptotic cell death, although antiangiogenic effect of FHL seemed more actively affected on growth inhibition than apoptotic potential in vivo system. Thus, Low anticoagulant FHL having antiangiogenic and apoptotic properties would provide benefits for the development of a new class of anticancer agent.

Purpose: Chemically modified heparin-DOCA was prepared and found to have markedly lower anticoagulant activity than heparin. In the present study, we elucidated the antiangiogenic and antitumoral activities of heparin-DOCA derivative., Methods: To evaluate the antiangiogenic and antitumoral effects of heparin-DOCA, capillary-like tube formation assay, Matrigel plug assay in vivo, western blotting for FGFR phosphorylation, ERK and p38 MAPK activities, tumor growth of SCC in vivo and immunostaining of blood vessels in tumor tissues were performed., Results: Heparin-DOCA inhibited capillary-like tubular structures of endothelial cells and bFGF-induced neovascularizations in Matrigel plug assays. Signaling experiments showed that heparin-DOCA significantly inhibited angiogenesis by suppressing the phosphorylation of FGFR and its downstream signal pathways (ERK and p38 MAPK activities). The antiangiogenic activity of this heparin derivative was found to be closely associated with antitumoral activity in a mouse model. In addition, histological evaluations supported the inhibitory effect of heparin-DOCA on blood vessel formation in tumor tissues., Conclusion: Heparin-DOCA derivative exerted a significant antitumoral effect by inhibiting angiogenesis resulting from the disruption of FGF/FGFR and its downstream signal pathways, and could be applied to treat various angiogenic diseases.

Purpose: We describe here a new method to estimate the oral drug permeability from the small intestine using surface plasmon resonance (SPR) technology. The interaction between drugs and brush border membrane (BBM) surfaces immobilized on biosensor chip were evaluated by measuring the SPR response signal., Methods: BBM vesicles, isolated from Sprague-Dawley (SD) rats, were immobilized onto the L1 chip composed of dextran derivatives with modified lipophilic residues. A SPR (BIAcore 3000) was used with L1 chip, and it was carried out in a running buffer, HEPES-buffered saline containing 0.1% DMSO. Fourteen drugs for the SPR experiments were flowed over the BBM immobilized L1 chip, and the response levels according to the BBM surfaces were evaluated directly in a continuous flow system., Results: The immobilized BBM surface on L1 chip was very stable, and it was regenerated by injecting a new BBM vesicle solution. It was evident that drug binding events, using BBM surfaces, directly provides information that predicts the Fa value in human for transcellularly absorbed drugs. The throughput to assay each drug at a single concentration is 100 drugs for 24 h., Conclusions: The interaction between drugs and small intestinal surfaces was successfully assayed using SPR technology, and this SPR analysis exhibited advantages: lack of labeling requirements, the real-time acquirement of various results, and the repeated use for various drugs.

Purpose: To prepare the surface generated by small intestinal brush border membrane vesicles (BBMVs) for the surface plasmon resonance (SPR) analysis, which allows the real-time measurement of binding events occurring on the intestinal membrane., Methods: BBMVs were isolated from Sprague-Dawley rats, suspended in HEPES-buffered saline, and flowed over the surface of a SPR sensor chip composed of dextran derivatives modified with lipophilic residues. The surface coverage was determined from binding of bovine serum albumin to BBMV-immobilized sensor chip. The performance of BBMVs immobilized was evaluated by their interaction with otilonium bromide and bile salts., Results: The stable BBMV surface was achieved when BBMV suspension was flowed over the sensor chip for 8 h at a rate of 2 microl/min. The flow of otilonium bromide resulted in an increased SPR signal because of its binding to calcium channel, which is known to be distributed over the gastrointestinal tact. When bile salts were flowed over ileal and duodenal BBMV surfaces, respectively, a slightly higher SPR signal was observed in the ileal BBMV surface, indicating the specific interaction of bile salts with bile acid transporters., Conclusions: BBMV surfaces may be useful for the estimation of binding events on the intestinal membrane by SPR analysis, especially for the drugs that are orally administrated.

Purpose: In this study, conjugates of heparin and deoxycholic acid were synthesized in order to enhance the heparin absorption in the GI tract. Oral delivery of heparin is a preferred therapy in the treatment of patients who are at high risk of deep vein thrombosis and pulmonary embolism., Methods: Several different kinds of heparin derivatives were synthesized, and their absorption in the GI tract was determined by activated partial thromboplastin time (aPTT) and factor Xa (FXa) assay. Any histological changes caused by heparin derivatives were examined by hematoxylin and eosin (H&E) stain and transmission electron microscopy (TEM)., Results: After administering heparin-DOCA orally, the clotting time in aPTT assay was increased with the increase of the coupled DOCA amount. The maximum clotting time of heparin-DOCA was 136+/-33 sec at 200 mg/kg of oral dose. This value was 7 times higher than the baseline. The absorption of heparin-cholesterol, heparin-palmitic acid, and heparin-lauric acid conjugates in the GI tract was lower than that of heparin-DOCA. Histological examination of the GI tract indicated that heparin derivatives did not cause any damage to the microvilli and the cell layer., Conclusions: DOCA coupled with heparin greatly enhanced absorption of heparin in the GI tract, and this enhancing effect was induced without changing the tissue structure of the GI wall.