Suppressive effect of a hot water extract of adzuki beans (Vigna angularis) on hyperglycemia after sucrose loading in mice and diabetic rats

A hot water extract obtained by boiling adzuki beans (Vigna angularis) to produce bean paste for Japanese cake showed inhibitory activity against alpha-glucosidase, alpha-amylase, maltase, sucrase, and isomaltase after HP-20 column chromatography. The IC(50) values for each hydrolylase were 0.78 mg/ml (alpha-amylase), 2.45 mg/ml (maltase), 5.37 mg/ml (sucrase), and 1.75 mg/ml (isomaltase). The active fraction showed potential hypoglycemic activity in both normal mice and streptozotocin (STZ)-induced diabetic rats after an oral administration of sucrose, but did not show any effect on the blood glucose concentration after glucose administration, suggesting that the active fraction suppressed the postprandial blood glucose level by inhibiting alpha-glucosidase and alpha-amylase, irrespective of the endogenous blood insulin level.     

The prostacyclin analogue beraprost sodium prevents development of arterial stiffness in elderly patients with cerebral infarction

Prostacyclin (PGI(2)) inhibits platelet aggregation, smooth muscle cell proliferation, and vasoconstriction. Arterial stiffness assessed by pulse wave velocity (PWV) predicts mortality in various cardiovascular diseases. To study the preventive effects of a prostacyclin analogue, beraprost sodium, on arterial PWV values in elderly patients with cerebral infarction. Forty-four patients with a history of cerebral infarction received beraprost sodium (120 microg/day p.o.) or no beraprost sodium (control) for 3 months. Arterial PWV and ankle brachial indices (ABI) were determined prior to starting the medication and after 3 months of medication. Initially, there were no differences in age, blood pressure, and body mass index. Further, PWV or ABI did not differ between the beraprost sodium group (n = 22) and the control group (n = 22). After 3 months, PWV in beraprost sodium group was significantly reduced (-123 +/- 282) when compared with the control group (147 +/- 274)(P = 0.006). ABI was not significantly different when comparing the two groups at 3 months. Long-term administration of beraprost sodium prevents the decline in arterial biomechanics in elderly patients with cerebral infarction.     

Identification of beta-tubulin isoform V as an autoantigen in allergic rhinitis by a proteomic approach

Autoantibodies to IgE and beta2-adrenergic receptor have been reported in patients with allergic rhinitis. To investigate whether autoimmunity in allergic rhinitis is directed to such limited molecules or directed to a wide range of self proteins, we here attempted to survey autoantigens/autoantibodies comprehensively, using proteomics. Specifically, we separated proteins extracted from peripheral blood mononuclear cells by 2-dimensional electrophoresis and then detected autoantigens by subsequent western blotting with sera from patients with allergic rhinitis. As a result, we detected multiple autoantigens, some of which were further identified by mass fingerprinting. Next, we confirmed antigenicity of one of the identified autoantigens, beta-tubulin isoform V (beta-tubV), using a recombinant protein and then measured prevalence of the anti-beta-tubV autoantibodies. As a result, 52% of the tested patients with allergic rhinitis were found to possess anti-beta-tubV autoantibodies. Our study indicates that autoimmunity is a common phenomena and beta-tubV is one of the major autoantigens in allergic rhinitis.     

The significant effect of the carbohydrate structures on the DNA photocleavage of the quinoxaline-carbohydrate hybrids

The novel DNA interactive quinoxaline-carbohydrate hybrids possessing disaccharides as the carbohydrate moieties were designed and synthesized, and their DNA photocleaving abilities were evaluated in order to examine the effect of the disaccharide structures. The configurations of the glycosidic bonds in the disaccharide strongly affected the DNA photocleaving ability, and two beta-glycosidic bond linkages were very effective for the DNA photocleavage. Furthermore, the quinoxaline-disaccharide hybrids exhibited selective cytotoxicity against cancer cells with photoirradiation.     

Direct observation of poly(3-hydroxybutyrate) depolymerase adsorbed on polyester thin film by atomic force microscopy

Poly[(R)-3-hydroxybutyrate] (PHB) depolymerases adsorbed on poly(L-lactide) (PLLA) thin film were directly observed by atomic force microscopy (AFM). A PLLA thin film of 100 nm thickness was prepared on a silicon wafer by spin-cast method. The PLLA thin film was treated at 220 degrees C and quenched to room temperature, resulting in the formation of a completely amorphous film with a smooth surface. Then, the PHB depolymerases from Pseudomonas stutzeri YM1006 and Ralstonia pickettii T1 were dispersed on the amorphous PLLA thin film. Direct AFM observation has revealed that the PHB depolymerases bind in an elliptic shape on the surface of the PLLA thin film and that a small ridge is created around each enzyme molecule. After removal of the enzymes with 40% ethanol aqueous solution, small hollows were found on the PLLA thin film. These results suggest that a PHB depolymerase interacts with polyester molecules during their adsorption to make a hollow on the substrate surface.     

C17,20-lyase inhibitors I. Structure-based de novo design and SAR study of C17,20-lyase inhibitors

Novel nonsteroidal C(17,20)-lyase inhibitors were synthesized using de novo design based on its substrate, 17 alpha-hydroxypregnenolone, and several compounds exhibited potent C(17,20)-lyase inhibition. However, in vivo activities were found to be short-lasting, and in order to improve the duration of action, a series of benzothiophene derivatives were evaluated. As a result, compounds 9h, (S)-9i, and 9k with nanomolar enzyme inhibition (IC(50)=4-9 nM) and 9e (IC(50)=27 nM) were identified to have powerful in vivo efficacy with extended duration of action. The key structural determinants for the in vivo efficacy were demonstrated to be the 5-fluoro group on the benzothiophene ring and the 4-imidazolyl moiety. Superimposition of 9k and 17 alpha-hydroxypregnenolone demonstrated their structural similarity and enabled rationalization of the pharmacological results. In addition, selected compounds were also identified to be potent inhibitors of human enzyme with IC(50) values of 20-30 nM.     

Synthesis and evaluation of 6-methylene-bridged uracil derivatives. Part 2: optimization of inhibitors of human thymidine phosphorylase and their selectivity with uridine phosphorylase

A series of novel 6-methylene-bridged uracil derivatives have been optimized for clinical use as the inhibitors of human thymidine phosphorylase (TP). We describe their synthesis and evaluation. Introduction of a guanidino or an amidino group enhanced the in vitro inhibitory activity of TP comparing with formerly reported inhibitor 1. Their selectivity for TP based on uridine phosphorylase inhibitory activity was also evaluated. Compound 2 (TPI) has been selected for clinical evaluation based on its strong TP inhibition and excellent modulation of 2'-deoxy-5-(trifluoromethyl)uridine (F(3)dThd) pharmacokinetics. As a result, TAS-102 (a combination of F(3)dThd and TPI) is currently in phase 1 clinical studies.     

Design and synthesis of novel hydrophilic spacers for the reduction of nonspecific binding proteins on affinity resins

Tubulin and actin often bind nonspecifically to affinity chromatography resins, complicating research toward identifying the cellular targets. Reduction of nonspecific binding proteins is important for success in finding such targets. We herein disclose the design, synthesis, and effectiveness in reduction of nonspecific binding proteins, of novel hydrophilic spacers (2-5), which were introduced between matrices and a ligand. Among them, tartaric acid derivative (5) exhibited the most effective reduction of nonspecific binding proteins, whilst maintaining binding of the target protein. Introduction of 5 on TOYOPEARL reduced tubulin and actin by almost 65% and 90% compared to that without the hydrophilic spacer, respectively, with effective binding to the target protein, FKBP12.     

Enforced Expression of Oxygen-Regulated Protein,ORP150, Induces Vacuolar Degeneration in Mouse Myocardium

Although the 150 kDa oxygen-regulated protein (ORP150) is known as a protein induced by low oxygen tension or ischemical insult, its possible role has not been fully investigated in vivo. To investigate the intracellular function of this protein, we generated the ORP150 over-expressing transgenic mice (ORP-Tg mice) under -actin promoter, and established three independent lines of the transgene expressed mice. All lines invariably showed growth retardation. Over-expression of ORP150 was confirmed by western blotting in heart, brain, spleen, skeletal muscle, pancreas, lung, thymus, and kidney. To ascertain the relationship between the over-expression of the ORP150 and the growth retardation in the transgenic mice, we examined pathological changes in the transgenics. In the ORP-Tg mice, vacuolar degeneration appeared in the heart. The degeneration in the myocytes became conspicuous with advancing age. Immunostaining demonstrated ORP150 in the vacuoles of degenerating myocytes. Electron microscopical findings revealed striking development of intracellular membrane system, for example, rough endoplasmic reticula (rER), vacuoles and Golgi bodies, swelling of sarcoplasmic reticulum, and lysis of myofibrils and mitochondria. These findings indicate that ORP150 may locate in the rER and other outer compartment of ER, and that constitutive over-expression of ORP150 in the heart induces vacuolar degeneration in myocytes, resulting in growth retardation of the transgenics.     

Involvement of c-Jun N-terminal kinase in amyloid precursor protein-mediated neuronal cell death

Amyloid precursor protein (APP), the precursor of Abeta, has been shown to function as a cell surface receptor that mediates neuronal cell death by anti-APP antibody. The c-Jun N-terminal kinase (JNK) can mediate various neurotoxic signals, including Abeta neurotoxicity. However, the relationship of APP-mediated neurotoxicity to JNK is not clear, partly because APP cytotoxicity is Abeta independent. Here we examined whether JNK is involved in APP-mediated neuronal cell death and found that: (i) neuronal cell death by antibody-bound APP was inhibited by dominant-negative JNK, JIP-1b and SP600125, the specific inhibitor of JNK, but not by SB203580 or PD98059; (ii) constitutively active (ca) JNK caused neuronal cell death and (iii) the pharmacological profile of caJNK-mediated cell death closely coincided with that of APP-mediated cell death. Pertussis toxin (PTX) suppressed APP-mediated cell death but not caJNK-induced cell death, which was suppressed by Humanin, a newly identified neuroprotective factor which inhibits APP-mediated cytotoxicity. In the presence of PTX, the PTX-resistant mutant of Galphao, but not that of Galphai, recovered the cytotoxic action of APP. These findings demonstrate that JNK is involved in APP-mediated neuronal cell death as a downstream signal transducer of Go.