Effects of soybean beta-conglycinin on hepatic lipid metabolism and fecal lipid excretion in normal adult rats

beta-Conglycinin decreased blood triacylglycerol (TAG) levels in male Wistar adult rats. Liver mitochondrial carnitine palmitoyltransferase activity in the beta-conglycinin-fed group significantly increased as against the casein-fed group. Hepatic fatty acid synthase activity in the beta-conglycinin group significantly decreased as against that of the casein-fed group. Fecal fatty acid excretion in the beta-conglycinin group was significantly higher than in the casein group.     

Royal jelly inhibits the production of proinflammatory cytokines by activated macrophages

In this study, we have examined the anti-inflammatory actions of royal jelly (RJ) at a cytokine level. When supernatants of RJ suspensions were added to a culture of mouse peritoneal macrophages stimulated with lipopolysaccharide and IFN-gamma, the production of proinflammatory cytokines, such as TNF-alpha, IL-6, and IL-1, was efficiently inhibited in a dose-dependent manner without having cytotoxic effects on macrophages. This suggests that RJ contains factor(s) responsible for the suppression of proinflammatory cytokine secretion. We named the factor for honeybees RJ-derived anti-inflammatory factor (HBRJ-AIF), and further investigated the molecular aspects of it. Size fractionation study showed that HBRJ-AIF is composed of substances of low (< 5 kDa) and high (> 30 kDa) molecular weights, with the former being a major component. Chromatographic analysis showed that MRJP3 is one candidate for the HBRJ-AIF with high molecular weights. Thus, our results suggest that RJ has anti-inflammatory actions through inhibiting proinflammatory cytokine production by activated macrophages.     

Protective effects of quercetin and its metabolites on H2O2-induced chromosomal damage to WIL2-NS cells

We investigated chromosomal damage caused by a typical flavonoid, quercetin, and its two conjugates, quercetin-3-O-sulfate and isorhamnetin, and their protective effects against chromosomal damage induced by H2O2. The chromosomal damage was detected by the cytokinesis-block micronucleus (CBMN) assay using a lymphoblastoid cell line, WIL2-NS. We found that quercetin itself induced chromosomal damage at 10 microM, but quercetin-3-O-sulfate and isorhamnetin did not induce damage up to 30 microM. In the medium used for the CBMN assay, quercetin (at 100 microM) generated a high concentration of H2O2, but the two conjugates did not at the same concentration. On the other hand, pretreatment with quercetin (at 1 microM), quercetin-3-O-sulfate (at 10 microM), and isorhamnetin (at 5 microM) prevented H2O2-induced chromosomal damage to WIL2-NS cells. These findings suggest that the induction and prevention of H2O2-induced chromosomal damage are different between quercetin and its metabolites.     

Highly potent PDE4 inhibitors with therapeutic potential

Based on the hypothesis that the dose-limiting side effects of PDE4 inhibitors could be mediated via the central nervous system (CNS), design and synthesis of a hydrophilic analogue is considered to be one approach to improving the side-effect profile of Ariflo 1. Water-soluble piperidine derivatives were found to possess therapeutic potential.     

Synergism between cysteinyl leukotrienes and thromboxane A2 to induce allergic late phase nasal blockage in guinea pigs

We examined whether cysteinyl leukotrienes (CysLTs) and thromboxane (TX) A2 are synergistically involved in a cedar pollen-induced allergic late phase nasal blockage in guinea pigs. Sensitized animals were repeatedly challenged by pollen inhalation once every week. Combined treatment with pranlukast (a CysLT antagonist) and seratrodast (a TXA2 antagonist) inhibited late phase nasal blockage, but the magnitude of inhibition (approximately 50%) was equal to those of the respective single treatments, suggesting that CysLTs produced late after challenge induces TXA2 production in the nasal tissue, as in the case of the lung of this species. However, pranlukast did not affect TXB2 increase in the nasal tissue. In contrast, combined intranasal instillation of LTD4 and U-46619 (a TXA2 mimetic) produced much greater nasal blockage than single administration of each agonist in sensitized animals. Therefore, allergic late phase nasal blockage should be induced by synergistic activity of CysLTs and TXA2 at the effector organ.     

Development of flight performance in the brown booby

How do birds acquire flight skills after fledging? This issue is important, as it is closely related to variation in the duration of offspring care, the causes of which remain unknown. In this study, we raised hatchling brown boobies, Sula leucogaster, and attached an acceleration data logger to each bird at fledging to record its movements. This allowed us to quantify precisely the time spent flapping, gliding and resting. The duration of foraging trips and proportion of time spent gliding during flight increased with the number of days since fledging, whereas the proportion of time spent in flight decreased. This indicates that brown boobies gradually acquire efficient flight skills during the post-fledging period, which might be the proximate cause of the long postfledging care period in this species. To the authors' knowledge, this is the first study to record precisely the ontogeny of flight behaviour in birds.     

Highly potent PDE4 inhibitors with therapeutic potential

The hypothesis that the dose-limiting side effects of PDE4 inhibitors could be mediated via the central nervous system prompted us to design and synthesize a hydrophilic piperidine analog to improve the side effect profile of Ariflo 1, which is an orally active second-generation PDE4 inhibitor. During evaluation of various water-soluble piperidine analogs, 2a-b, 11b-14b, and 17a showed therapeutic potential in cross-species comparison studies. The following three findings were obtained: (1) The hydroxamic acid group, a well known metal chelator, caused a marked increase of inhibitory activity. (2) Water-soluble piperidine analogs lacked the configurational isomerism of Ariflo 1 without loss of inhibitory activity. (3) Replacement of the 4-methoxy residue with a difluoromethoxy residue led to an increase of in vivo potency. Structure-activity relationships are presented. Single-dose rat pharmacokinetic data for 11b, 12b, and 17a are also presented.     

Hydroxyl radical generation caused by the reaction of singlet oxygen with a spin trap, DMPO, increases significantly in the presence of biological reductants

Photosensitizers newly developed for photodynamic therapy of cancer need to be assessed using accurate methods of measuring reactive oxygen species (ROS). Little is known about the characteristics of the reaction of singlet oxygen (₁O₂) with spin traps, although this knowledge is necessary in electron spin resonance (ESR)/spin trapping. In the present study, we examined the effect of various reductants usually present in biological samples on the reaction of ₁O₂ with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). The ESR signal of the hydroxyl radical (•OH) adduct of DMPO (DMPO-OH) resulting from ₁O₂-dependent generation of •OH strengthened remarkably in the presence of reduced glutathione (GSH), 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), ascorbic acid, NADPH, etc. A similar increase was observed in the photosensitization of uroporphyrin (UP), rose bengal (RB) or methylene blue (MB). Use of 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide (DEPMPO) as a spin trap significantly lessened the production of its •OH adduct (DEPMPO-OH) in the presence of the reductants. The addition of DMPO to the DEPMPO-spin trapping system remarkably increased the signal intensity of DEPMPO-OH. DMPO-mediated generation of •OH was also confirmed utilizing the hydroxylation of salicylic acid (SA). These results suggest that biological reductants enhance the ESR signal of DMPO-OH produced by DMPO-mediated generation of •OH from ₁O₂, and that spin trap-mediated •OH generation hardly occurs with DEPMPO.     

Structure-activity study of L-amino acid-based N-type calcium channel blockers

Synthesis and structure-activity relationship (SAR) study of L-amino acid-based N-type calcium channel blockers are described. The compounds synthesized were evaluated for inhibitory activity against both N-type and L-type calcium channels focusing on selectivity to reduce cardiovascular side effects due to blocking of L-type calcium channels. In the course of screening of our compound library, N-(t-butoxycarbonyl)-L-aspartic acid derivative 1a was identified as an initial lead compound for a new series of N-type calcium channel blockers, which inhibited calcium influx into IMR-32 human neuroblastoma cells with an IC(50) of 3.4 microM. Compound 1a also exhibited blockade of N-type calcium channel current in electrophysiological experiment using IMR-32 cells (34% inhibition at 10 microM, n=3). As a consequence of conversion of amino acid residue of 1a, compound 12a, that include N-(t-butoxycarbonyl)-L-cysteine, was found to be a potent N-type calcium channel blocker with an IC(50) of 0.61 microM. Thus, L-cysteine was selected as a potential structural motif for further modification. Optimization of C- and N-terminals of L-cysteine using S-cyclohexylmethyl-L-cysteine as a central scaffold led to potent and selective N-type calcium channel blocker 21f, which showed improved inhibitory potency (IC(50) 0.12 microM) and 12-fold selectivity for N-type calcium channels over L-type channels.     

Ether-linked analogue of 2-arachidonoylglycerol (noladin ether) was not detected in the brains of various mammalian species

2-Eicosa-5',8',11',14'-tetraenylglycerol (2-AG ether, HU310, noladin ether) is a metabolically stable ether-linked analogue of 2-arachidonoylglycerol (2-AG), an endogenous cannabinoid receptor ligand. 2-AG ether has been used as a valuable experimental tool by a number of investigators. Recently, several groups reported that 2-AG ether is present in mammalian brains. We examined in detail whether 2-AG ether actually exists in the brains of various mammalian species. We found that 2-AG ether is not present, at least in an appreciable amount, in the rat brain by gas chromatography-mass spectrometry analysis and fluorometric high performance liquid chromatography analysis. The level of 2-AG ether in the rat brain was below 0.2 pmol/g brain, if at all present. Similar results were obtained for the mouse brain, hamster brain, guinea-pig brain and pig brain. The fact that 2-AG ether was not detected in the brains of various mammalian species is consistent with the fact that an ether bond is formed through enzymatic replacement of the fatty acyl moiety of 1-acyl dihydroxyacetone phosphate by a fatty alcohol, the resultant 1-O-alkyl dihydroxyacetone phosphate being a common intermediate of the biosynthesis of ether-linked lipids in mammalian tissues. It is rather questionable whether 2-AG ether is present in appreciable amounts in the brain and acts as an 'endogenous' cannabinoid receptor ligand.