We previously found a lipophilic fraction of the methanol/chloroform extract of a brown alga, Eisenia nipponica, that had an antiallergic effect in a murine ear swelling test. In this study, we purified the active component from the lipophilic fraction using high performance liquid chromatography and analyzed the mass and nuclear magnetic resonance spectra. This uncovered the phlorotannin dieckol, which exhibited antiallergic effects in an ear swelling test using mice sensitized by arachidonic acid, 12-O-tetradecanoylphorbol-13-acetate, and oxazolone.
View Article and Find Full Text PDFPhlorotannin is the collective term for polyphenols derived from brown algae belonging to the genera , , , and etc. Since the incidence of allergies is currently increasing in the world, there is a focus on phlorotannins having anti-allergic and anti-inflammatory effects. In this study, six purified phlorotannins (eckol; 6,6'-bieckol; 6,8'-bieckol; 8,8'-bieckol; phlorofucofuroeckol (PFF)-A and PFF-B) from , orally administered to mice, were examined for their suppression effects on ear swelling.
View Article and Find Full Text PDFIn the silkworm Bombyx mori, the diapause hormone-pheromone biosynthesis activating neuropeptide gene, DH-PBAN, is a neuropeptide gene that encodes a polypeptide precursor consisting in five Phe-X-Pro-Arg-Leu-NH(2) (FXPRL) amide (FXPRLa) neuropeptides; DH (diapause hormone), PBAN (pheromone-biosynthesis-activating neuropeptide) and α-, β- and γ-SGNPs (subesophageal ganglion neuropeptides). These neuropeptides are synthesized in DH-PBAN-producing neurosecretory cells contained within three neuromeres, four mandibular cells, six maxillary cells, two labial cells (SLb) and four lateral cells of the subesophageal ganglion. DH is solely responsible, among the FXPRLa peptide family, for embryonic diapause.
View Article and Find Full Text PDFBombyx mori eggs enter diapause immediately after completion of mesoderm segregation. HCl treatment of approximately 24-hour-old eggs (germband formation stage) is well known to be the most effective procedure to prevent entry into diapause, although the molecular mechanism remains unclear. In this study, we examined the protein composition of diapausing and nondiapausing eggs after various HCl treatments known to prevent or break diapause and found that proteins of approximately 11 and 8 kDa disappeared immediately after HCl treatment.
View Article and Find Full Text PDFWe previously reported that yamamarin, a pentapeptide with an amidated C-terminus (DILRG-NH(2)) isolated from larvae of the silkmoth, and its palmitoylated analog (C16-DILRG-NH(2)) suppressed proliferation of rat hepatoma (liver cancer) cells. In this study, we investigated the structure-activity relationship of yamamarin by in vitro assay and spectroscopic methods (CD and NMR) for various analogs. The in vitro assay results demonstrated that the chemical structure of the C-terminal part (-RG-NH(2)) of yamamarin is essential for its activity.
View Article and Find Full Text PDFA palmitoyl conjugate of an insect pentapeptide that occurs in diapausing insects causes a reversible cell-cycle arrest and suppresses mitochondrial respiration. This peptide compound also causes growth arrest in murine leukemic cell line expressing human gene Bcr/Abl and a farnesoyl peptide induces embryonic diapause in Bombyx mori. These results demonstrate that the insect peptide compounds can lead to the understanding of a common pathway in developmental arrest in animals and may provide a new peptidominetic analog in the development of biopharmaceuticals and pest management.
View Article and Find Full Text PDFThe FXPRL-amide peptide family (pyrokinin/PBAN family) consists of insect peptides that function broadly in insect life processes and are characterized by a conserved C-terminal motif. In the silkworm, Bombyx mori, sex pheromone biosynthesis and induction of embryonic diapause are regulated by peptides from this family. To elucidate other functions of Bombyx FXPRL-amide peptides, we analyzed the tissue expression patterns of two known Bombyx G-protein coupled receptors for these peptides.
View Article and Find Full Text PDFThe thermodynamic effects of the disulfide bond of the fragment protein of the starch-binding domain of Aspergillus niger glucoamylase was investigated by measuring the thermal unfolding of the wild-type protein and its two mutant forms, Cys3Gly/Cys98Gly and Cys3Ser/Cys98Ser. The circular dichroism spectra and the thermodynamic parameters of binding with beta-cyclodextrin at 25 degrees C suggested that the native structures of the three proteins are essentially the same. Differential scanning calorimetry of the thermal unfolding of the proteins showed that the unfolding temperature t1/2 of the two mutant proteins decreased by about 10 degrees C as compared to the wild-type protein at pH 7.
View Article and Find Full Text PDFEisenia arborea is an edible brown alga occasionally used as a folk medicine in gynecopathy in Japan. A new phlorotannin was isolated from the alga during our search for naturally occurring anti-allergic compounds from edible algae guided by the inhibitory effect on histamine release from rat basophile leukemia (RBL)-2H3 cells. The phlorotannin was called "phlorofucofuroeckol-B.
View Article and Find Full Text PDFBiochem Biophys Res Commun
May 2006
Bombyx diapause hormone was the first chemical substance identified as a maternal control factor that arrests offspring development. However, the molecular mechanisms by which the hormone transduces the signal to the oocyte that induces embryonic diapause immediately after mesoderm segmentation are not fully understood. Here, we describe a cDNA for a G protein-coupled diapause hormone receptor with seven transmembrane domains.
View Article and Find Full Text PDFFive types of flavonol were isolated from seabuckthorn (Hippophae rhamnoides) and identified by mass, 1H- and 13C-NMR. The proliferations of human promyelotic leukemia HL-60 cells were inhibited as the concentrations of these flavonols were increased. The order of the extent of growth inhibition by the flavonols at a concentration of 20 microM is as follows: pentamethylquercetin > syringetin > isorhamnetin > quercetin > kaempherol > myricetin.
View Article and Find Full Text PDFIn the silkworm Bombyx mori, diapause hormone (DH) is produced in the female subesophageal ganglion (SG) and induces embryonic diapause by targeting developing ovaries. DH is processed from a precursor protein consisting of DH, pheromone biosynthesis activating neuropeptide (PBAN) and three other neuropeptides (SGNPs). Because these five neuropeptides share a common sequence, FXPRLamide, at the C-terminus, a direct and specific assay for DH itself is required in order to understand the profile of concentration changes.
View Article and Find Full Text PDFThe comparison of antioxidative activity between the hot water extract and ambient water extract of Japanese radish (daikon) was carried out. The activity of the hot water extract was higher than that of the ambient water extract. One of the antioxidants was isolated as L-tryptophan that should no change in its amount that was determined between the hot water extract and ambient water extract.
View Article and Find Full Text PDFWe have investigated the effects of maackiain and trifolirhizin (maackiain glycoside) isolated from sanzukon (Sophora Subprostrate Chen et T. Chen) on DNA of human promyelotic HL-60 leukemia cells. It was found that extent of induction of apoptosis by maackiain was larger than that by trifolirhizin in human leukemia HL-60 cells.
View Article and Find Full Text PDF2-O-methylisohemigossylic acid lactone, a sesquiterpene, was purified from roots of mokumen (Gossampinus malabarica) and identified by Mass, and (1)H- and (13)-NMR. This sesquiterpene displayed strong growth inhibitory effect against human promyelotic leukemia HL-60 cells. Apoptotic morphological change of the nucleus, including chromatin condensation was induced in the HL-60 cells treated with the sesquiterpene.
View Article and Find Full Text PDFWe have investigated the effect of lupeol (lup-20(29)-ene-3beta-ene-3-ol) isolated from mokumen (Gossampinus malabarica L. Merr) on DNA of human promyelotic HL-60 leukemia cells. Induction of apoptosis by lupeol was observed in human leukemia HL-60 cells.
View Article and Find Full Text PDFHot water soluble (HWS)-sesquiterpenes [anhydroperoxycostunolide and 3-oxo-eudesma-1,4(15),11(13)triene-12,6alpha-olide] were purified from Laurel (Laurus nobilis L.) and identified by Mass, and 1H- and 13C-NMR. These HWS-sesquiterpenes displayed strong growth inhibitory effect against human promyelotic leukemia HL-60 cells.
View Article and Find Full Text PDFSesquiterpenes (costunolide and zaluzanin D) were purified from laurel (Laurus nobilis L.) and identified by Mass, and 1H- and 13C-NMR. These sesquiterpenes displayed strong growth inhibitory effect against human promyelotic leukemia HL-60 cells.
View Article and Find Full Text PDFCyanidin 3-O-beta-D-glucoside (CG) was purified from black bean seed coat and other anthocyanins were prepared from red grape skin. These anthocyanins were identified by Mass, and 1H- and 13C-NMR. The effects of four anthocyanins on cell viability in human leukemia Molt 4B cells were investigated.
View Article and Find Full Text PDFProtodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated.
View Article and Find Full Text PDFThe exposure of human lymphoid leukemia Molt 4B cells to diol- and triol-types of phytol which were synthesized and identified by Mass, and 1H- and 13C-NMR, led to both growth inhibition and induction of programmed cell death (apoptosis). Morphological changes showing apoptotic bodies were observed in the Molt 4B cells treated with diol- and triol-types of phytol. The fragmentations of DNA by the diol- and triol-types of phytol to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, were observed to be both concentration- and time-dependent.
View Article and Find Full Text PDFWe have investigated the effects of 1,8-cineole [the main component of essential oil prepared from bay-leaves Laurus nobilis L.)] on DNA of human leukemia cell lines, Molt 4B, HL-60 and stomach cancer KATO III cells. Specific induction of apoptosis by 1,8-cineole was observed in human leukemia Molt 4B and HL-60 cells, but not in human stomach cancer KATO III cells.
View Article and Find Full Text PDFWe have investigated the effects of ar-turmerone isolated from turmeric (Curcuma longa L) on DNA of human leukemia cell lines, Molt 4B, HL-60 and stomach cancer KATO III cells. It was found that selective induction of apoptosis by ar-turmerone was observed in human leukemia Molt 4B and HL-60 cells, but not in human stomach cancer KATO III cells. Morphological changes showing apoptotic bodies were observed in the human HL-60 and Molt 4B cells treated with ar-turmerone.
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