Hoshi University is a private university in Shinagawa, Tokyo, Japan, specializing in pharmaceutical science. The predecessor of the school was founded 1922. After becoming coeducational in 1946, it was chartered as a university in 1950. Wikipedia.
Carrillo-Sepulveda M.A.,Georgia Regents University |
Matsumoto T.,Hoshi University
Cellular Physiology and Biochemistry | Year: 2014
Aims: Diabetes-induced vascular complications are associated with vascular smooth muscle cell (VSMC) phenotypic modulation, switching from a contractile to a synthetic-proliferative phenotype. Loss of caveolin-1 is involved with proliferation of VSMCs. We tested the hypothesis that mesenteric VSMCs from type 2 diabetic Goto-Kakizaki (GK) rat undergo phenotypic modulation and it is linked to decreased caveolin-1 expression.Methods: VSMCs were isolated from mesenteric arteries from GK rats and age-matched control Wistar rats. Western blotting was used to determine expression of target proteins such as caveolin-1, calponin (marker of differentiation), and proliferating cell nuclear antigen (PCNA, marker of proliferation). In addition, we measured intracellular reactive oxygen species (ROS) production using H2DCF-DA and activation of extracellular signal-regulated kinase (ERK1/2) by western blotting in VSMCs from GK stimulated with lipopolysaccharide (LPS), an endotoxin upregulated in diabetes.Results: Mesenteric VSMCs from diabetic GK rats exhibited decreased caveolin-1 and calponin expression and increased PCNA expression compared to control. Increased levels of ROS and phospho-ERK1/2 expression were also found in GK VSMCs. LPS augmented ROS and phosphorylated ERK1/2 levels to a greater extent in GK VSMCs than in control. Likewise, high glucose decreased caveolin-1 and calponin expression, increased PCNA expression and augmented ROS production in control mesenteric VSMCs.Conclusion: These results suggest that mesenteric VSMCs from diabetic GK rats undergo phenotypic modulation and it is associated with decreased caveolin-1 expression. These alterations may be due to enhanced inflammatory stimuli and glucose levels present in diabetic milieu. Copyright © 2014 S. Karger AG, Base.
Honda T.,Hoshi University
Heterocycles | Year: 2011
Samarium diiodide (SmI2) is a mild and selective one electron transfer reagent, and has become an important tool for developing a variety of useful and unique transformations. SmI2 has been utilized in a wide range of synthetic transformations ranging from interconversion of functional groups to carbon-carbon bond forming reactions. Among the various reactions developed for SmI2, we focused our attention on its use for fragmentation reactions. We have already established a regioselective carbon-carbon bond cleavage reaction of γ-halo carbonyl compounds, and its utilization in the synthesis of various types of biologically active natural products. However, a SmI2-promoted reductive carbon-nitrogen bond cleavage reaction has received relatively little attention. In this review article, we would like to describe a general carbon-nitrogen bond cleavage reaction of α-amino carbonyl compounds and the utilization of this methodology in the synthesis of a number of bioactive alkaloids, since this reaction proceeds in relatively high yield under mild reaction conditions. © The Japan Institute of Heterocyclic Chemistry.
Ihara M.,Hoshi University
Heterocycles | Year: 2011
Malaria, leishmaniasis, African sleeping sickness (African trypanosomiasis) and Chagas disease (American trypanosomiasis) are caused by different protozoan parasites. Although many people suffer from these diseases in tropical and subtropical areas, efficient medicines against these protozoan diseases are very few or absent. Efforts to develop new drugs against these neglected diseases led us to the discovery of SSJ-127 (62), which cured malaria and African trypanosomiasis mouse models by treatment with injection, SJL-01 (74) as a hit compound for leishmaniasis, and SSJ-183 (109) as a candidate against malaria, respectively. These compounds displayed novel modes of actions different from those of conventional medicines. © The Japan Institute of Heterocyclic Chemistry.
Onishi H.,Hoshi University
Expert Opinion on Drug Delivery | Year: 2011
Introduction: Recently, pharmacotherapy has advanced extensively, but there are still many refractory diseases which cannot be solved fully by existing therapeutic agents. Therefore, alternative medicine and health foods are now attracting much attention, for example, lactoferrin (LF): a multifunctional glycoprotein. As LF is non-toxic and low-cost, its application in healthcare and therapeutics is expected to be widespread. Areas covered: In this review, LF's general basic features are described. The interaction of LF with its receptors activates the immune system, including cytokine production and balance. In particular, the immune activation of orally administered LF is considered as a new strategy for the treatment of refractory diseases, such as inflammatory bowel disease, virus infection and tumor metastasis. Also mentioned are the problems associated with the use of LF. As LF is degraded rapidly in the body due to enzymatic hydrolysis, high amounts or frequent dosing is required; an appropriate delivery system may improve these problems and increase its efficiency. Expert opinion: Chemical modifications, such as PEGylation, can enhance the stability of LF in the body, resulting in increased efficacy. Also, liposomes and enteric or microparticulate formulations can promote the function of LF in oral administration due to target site delivery and protection of LF from enzymatic hydrolysis. These delivery systems are expected to improve the utility of LF. © 2011 Informa UK, Ltd.
Takahashi K.,Hoshi University |
Honda T.,Hoshi University
Organic Letters | Year: 2010
An intramolecular coupling of bromoalkynes with α,β-unsaturated esters afforded functionalized five-membered carbocycles and heterocycles with high diastereoselectivities in excellent yields. The vinyl bromides newly generated as the products serve as adequate intermediates for further chemical modification. © 2010 American Chemical Society.
Iwase Y.,Hoshi University |
Maitani Y.,Hoshi University
Molecular Pharmaceutics | Year: 2011
Medullary thyroid carcinoma (MTC) is a rare endocrine tumor that frequently metastasizes, but treatment with irinotecan (CPT-11) is limited because of side effects. MTC is known to overexpress the somatostatin receptor subtype 2 (SSTR2). Octreotide (Oct) is a somatostatin analogue that has a high binding affinity for SSTR and can be used as a tumor-targeting ligand. We prepared Oct-targeted liposomes loaded with CPT-11 using Oct-poly (ethylene glycol) (PEG)-lipid and evaluated Oct-mediated association and cytotoxicity of the liposomes with an MTC cell line TT. The association of higher concentrations of modified Oct-targeted liposomes with TT cells was significantly higher than PEGylated liposomes and was significantly inhibited by empty Oct-targeted liposomes but not by free Oct. With exposure for 96 h, the cytotoxicity of Oct-targeted liposomal CPT-11 (IC50: 1.05 ± 0.47 μM) was higher than free CPT-11 (IC50: 3.76 ± 0.61 μM) or PEGylated liposomal CPT-11 (IC50: 3.05 ± 0.28 μM). In addition, empty Oct-targeted liposomes showed significantly higher cytotoxicity than empty nontargeted liposomes at a concentration where free Oct did not show cytotoxicity, suggesting that Oct as a ligand showed cytotoxicity. Moreover, Oct-targeted liposomal CPT-11 led to significantly higher antitumor activity and prolonged the survival time compared with nontargeted liposomal and free CPT-11 at a one-third dose and lower administration times with free CPT-11. These findings indicated that Oct-targeted liposomes loaded with CPT-11 may offer considerable potential for MTC chemotherapy because cytotoxicity of both CPT-11 and Oct was enhanced by effective cellular uptake via SSTR2. © 2010 American Chemical Society.
Honda T.,Hoshi University
Chemical and Pharmaceutical Bulletin | Year: 2012
Synthesis of biologically active compounds, including natural products and pharmaceutical agents, is an important and interesting research area since the large structural diversity and complexity of bioactive compounds make them an important source of leads and scaffolds in drug discovery and development. Many structurally and also biologically interesting compounds, including marine natural products, have been isolated from nature and have also been prepared on the basis of a computational design for the purpose of developing medicinal chemistry. In order to obtain a wide variety of derivatives of biologically active compounds from the viewpoint of medicinal chemistry, it is essential to establish efficient synthetic procedures for desired targets. Newly developed reactions should also be used for efficient synthesis of desired compounds. Thus, recent progress in the synthesis of biologically active compounds by focusing on the development of new reactions is summarized in this review article. © 2012 The Pharmaceutical Society of Japan.
Development of samarium diiodide-promoted regioselective carbon-carbon bond cleavage reaction of γ-halo-and ε-halo-α,β-unsaturated carbonyl compounds: Application to the synthesis of biologically active natural products
Honda T.,Hoshi University
Heterocycles | Year: 2010
Samarium diiodide (SmI2), a mild and selective one electron transfer reagent, has been utilized in a wide range of synthetic transformations. Among the various reactions developed for SmI2, we focused on its use for fragmentation reactions, and established a regioselective carbon-carbon bond cleavage reaction of γ-halo carbonyl compounds. Utilization of this strategy in the synthesis of various types of biologically active natural products is discussed in this review article. © The Japan Institute of Heterocyclic Chemistry.
Hoshi University and Fujifilm Co. | Date: 2010-10-06
A rhodacyanine derivative represented by the following General Formula (1), wherein, in General Formula (1), R^(1), R^(2), and R^(3 )each independently represent an alkyl group which may be substituted; Y^(1 )and Y^(2 )each independently represent a hydrogen atom, a chlorine atom, or a fluorine atom provided that Y^(1 )and Y^(2 )do not represent hydrogen atoms at the same time; and X represents a counter anion. A pharmaceutical composition for treating leishmaniasis including the rhodacyanine derivative and a pharmaceutically acceptable carrier.
Hoshi University, Synstar Japan Co. and Schweizerisches Tropeninstitut | Date: 2011-01-05
Provided is a medicinal composition, in particular, a medicinal composition for treatment and/or prevention which has a high therapeutic effect on infection with a parasitic protozoa and a selective toxicity thereto and exhibits a life-prolonging effect and so on. A medicinal composition which contains as the active ingredient a benzo[a]phenoxazine compound represented by General formula (1) or a salt compound of the same, in particular, an agent for treating and/or preventing infection with a protozoa such as malaria, leishmaniasis, African trypanosomiasis, Chagas disease, toxoplasmosis, lymphatic filariasis, babesiosis or coccidium disease; and a novel compound which is contained therein as the active ingredient.