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1.
Ryo C. Yanagita Hiroaki Kamachi Masayuki Kikumori Harukuni Tokuda Nobutaka Suzuki Kiyotake Suenaga Hiroshi Nagai Kazuhiro Irie 《Bioorganic & medicinal chemistry letters》2013,23(15):4319-4323
Debromoaplysiatoxin (DAT) is a tumor promoter isolated from sea hare and exhibits anti-proliferative activity against several cancer cell lines. To clarify key residues that are responsible for its tumor-promoting activity, we focused on the chiral methoxy group in the side chain, whose role had not yet been discussed or examined before. Demethoxy-DAT (8) was derived from DAT and we evaluated its tumor-promoting activity, anti-proliferative activity, and ability to bind to protein kinase C (PKC) isozymes. Compound 8 showed somewhat weaker tumor-promoting activity than that of DAT both in vitro and in vivo, but showed higher anti-proliferative activity against several cancer cell lines. Although the affinity to novel PKC isozymes of 8 was comparable to that of DAT, the affinity to conventional PKC isozymes decreased slightly. These results suggest that the methoxy group of DAT is one of the key residues critical for tumor-promoting activity but not for anti-proliferative activity. Since the methoxy group has little influence on the molecular hydrophobicity, this is the first report showing that structural factors other than hydrophobicity in the side chain of DAT affected its biological activities. 相似文献
2.
Chandrasekaran Uma Burkhoff Daniel Ishikawa Kiyotake Swain Lija Sunagawa Kenji Mller Jacob Santos-Gallego Carlos Annamalai Shiva Udelson James Westenfeld Ralf Kapur Navin Qiao Xiaoying Wiora Julian Schfer Andreas Bernhardt Alexander Kochar Ajar Kloner Robert Faraz Haroon 《BMC cardiovascular disorders》2019,19(2):1-17
3.
Hisashi Kato-Noguchi Madoka Yamamoto Kazuya Tamura Toshiaki Teruya Kiyotake Suenaga Yoshiharu Fujii 《Plant Growth Regulation》2010,60(2):127-131
Aqueous methanol extracts of rattail fescue (Vulpia myuros) inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), timothy (Phleum pratense), Digitaria sanguinalis and Lolium multiflorum. Increasing the extract concentration increased the inhibition, suggesting that rattail fescue may have growth inhibitory
substances and possess allelopathic potential. The aqueous methanol extract of rattail fescue was purified and two main inhibitory
substances were isolated and identified by spectral data as (−)-3-hydroxy-β-ionone and (+)-3-oxo-α-ionol. Both substances
inhibited root and shoot growth of cress at concentrations greater than 0.3 μM. The concentrations required for 50% growth
inhibition on root and shoot growth of cress, lettuce, alfalfa, timothy, D. sanguinalis and L. multiflorum were 2.7–19.7 μM for (−)-3-hydroxy-β-ionone, and 2.1–34.5 μM for (+)-3-oxo-α-ionol. The concentration of (−)-3-hydroxy-β-ionone
and (+)-3-oxo-α-ionol, respectively, in rattail fescue was 7.8 and 3.7 μg g−1 fresh weight. Considering the endogenous level and the inhibitory activity, (−)-3-hydroxy-β-ionone and (+)-3-oxo-α-ionol
may work as allelopathic substances in rattail fescue through the growth inhibition of neighboring plant species. 相似文献
4.
Kuroda T Suenaga K Sakakura A Handa T Okamoto K Kigoshi H 《Bioconjugate chemistry》2006,17(2):524-529
The interaction between actin and aplyronine A, a potent antitumor and actin-depolymerizing substance of marine origin, was investigated by photoaffinity labeling experiments. Photoaffinity probes consisting of a side-chain portion of aplyronine A as a ligand, a diazirine moiety as a photoaffinity group, and a fluorophore as a detecting group were synthesized. Photolabeling experiments between actin and the probe were carried out. Actin was successfully photolabeled by the fluorescent probe and visualized clearly. The present results provide the first chemical evidence for the direct interaction between actin and the side-chain portion of aplyronine A. 相似文献
5.
The fern Dicranopteris linearis Underw. (Old world forkedfern, Gleicheniaceae), the most widely distributed fern throughout tropical to temperature regions, dominates and often forms large pure colonies. Allelopathic chemical interaction of the fern was speculated to play an important role in the dominance. However, potential mechanisms, in particular, the allelopathic substance have not been reported. The objective of this study was the identification of its potential allelopathic substance and the evaluation of the ecological role of the substance. Extracts of D. linearis had an inhibitory effect on Echinochloa colonum and Avena fatua which are found near colonies of D. linearis in natural ecosystems. The extract was purified and a main inhibitory substance was isolated. The chemical structure of the substance was determined by high-resolution MS, and 1H- and 13C-NMR spectral data and optical rotation as epicatechin-(2β → O → 7,4β → 8)-epicatechin-(4β → 8)-epicatechin (cinnamtannin B-1). Cinnamtannin B-1 inhibited the shoot and root growth of A. fatua and E. colonum at concentrations greater than 0.2–0.5 mM, and the concentrations required for 50 % growth inhibition on shoot and root growth of these plants were 0.34–1.31 mM. Cinnamtannin B-1 was found in soil under the colony, at concentrations of 4.3 and 14.5 mM in soil at the edge of and under the colony, respectively. These concentrations were over the concentration required for 50 % growth inhibition. Therefore, cinnamtannin B-1 may work as an allelopathic agent of D. linearis and may contribute to the establishment of pure colonies of D. linearis. 相似文献
6.
Eisuke Sato Maho Morita Haruo Ogawa Masato Iwatsuki Rei Hokari Aki Ishiyama Satoshi Ōmura Arihiro Iwasaki Kiyotake Suenaga 《Bioorganic & medicinal chemistry letters》2018,28(3):298-301
Biselyngbyaside, an 18-membered macrolide glycoside from marine cyanobacteria, and its derivatives are known to be sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) inhibitors. Recently, a SERCA orthologue of the malaria parasite, PfATP6, has attracted attention as a malarial drug target. To provide a novel drug lead, we designed new synthetic analogs of biselyngbyolide B, the aglycone of biselyngbyaside, based on the co-crystal structure of SERCA with biselyngbyolide B, and synthesized them using the established synthetic route for biselyngbyolide B. Their biological activities against malarial parasites were evaluated. 相似文献
7.
Ikuko Kozawa Kuniki Kato Toshiaki Teruya Kiyotake Suenaga Kazuo Umezawa 《Bioorganic & medicinal chemistry letters》2009,19(18):5380-5382
Previously we found that (−)-DHMEQ, a specific NF-κB inhibitor, covalently bound to a specific cysteine of NF-κB component proteins. In the course of formation of the (−)-DHMEQ and protected cysteine conjugate, we observed an unusual intramolecular N→O acyl group migration. 相似文献
8.
A.K.M. Mominul Islam Osamu Ohno Kiyotake Suenaga Hisashi Kato-Noguchi 《Journal of plant physiology》2014
Leucas aspera (Lamiaceae), an aromatic herbaceous plant, is well known for many medicinal properties and a number of bioactive compounds against animal cells have been isolated. However, phytotoxic substances from L. aspera have not yet been documented in the literature. Therefore, current research was conducted to explore the phytotoxic properties and substances in L. aspera. Aqueous methanol extracts of L. aspera inhibited the germination and growth of garden cress (Lepidum sativum) and barnyard grass (Echinochloa crus-galli), and the inhibitory activities were concentration dependent. These results suggest that the plant may have phytotoxic substances. The extracts were then purified by several chromatographic runs. The final purification was achieved by reversed-phase HPLC to give an equilibrium (or inseparable) 3:2 mixture of two labdane type diterpenes (compounds 1 and 2). These compounds were characterized as (rel 5S,6R,8R,9R,10S,13S,15S,16R)-6-acetoxy-9,13;15,16-diepoxy-15-hydroxy-16-methoxylabdane (1) and (rel 5S,6R,8R,9R,10S,13S,15R,16R)-6-acetoxy-9,13;15,16-diepoxy-15-hydroxy-16-methoxylabdane (2) by spectroscopic analyses. A mixture of the two compounds inhibits the germination and seedling growth of garden cress and barnyard grass at concentrations greater than 30 and 3 μM, respectively. The concentration required for 50% growth inhibition (I50) of the test species ranges from 31 to 80 μM, which suggests that the mixture of these compounds, are responsible for the phytotoxic activity of L. aspera plant extract. 相似文献
9.
Summary A 17-month-old girl with a partial trisomy of distal 8q derived from her mother, who has a mosaic 8q23.3q24.13 deletion, was studied. Both showed a relatively mild phenotype of trichorhinophalangeal syndrome I. The karyotype of the proposita was designated as: 46,XX,-8,+der(8),inv ins(8;8)(p23.1;q24.13q23.3)mat. Her phenotype was considered similar to that of her mother despite the trisomies of distal 8q. She seems to be the first example of a partial trisomy of distal 8q derived from a parent with an interstitial deletion of a distal 8q segment and trichorhinophalangeal syndrome I. 相似文献
10.
Evaluation of bidirectional transfer of plasma DNA through placenta 总被引:11,自引:0,他引:11
Sekizawa A Yokokawa K Sugito Y Iwasaki M Yukimoto Y Ichizuka K Saito H Okai T 《Human genetics》2003,113(4):307-310
To clarify the origin of cell-free fetal DNA in maternal plasma, we analyzed bidirectional transfer of plasma DNA between fetus and mother. We analyzed maternal and fetal plasma DNA obtained from 15 pregnant women at the time of Cesarean section. The subjects were five patients with preeclampsia and 10 gestational-age-matched normal controls. DNA was extracted from 1.5-ml plasma samples and the cellular fraction of maternal and umbilical blood. Seven polymorphic marker genes were analyzed. The relative concentration of fetal DNA in maternal plasma and maternal DNA in cord blood were evaluated. The relative concentration of maternal DNA in fetal circulation (median, 0.9%; range, 0.2–8.4%) was significantly lower than that of fetal DNA in maternal blood (14.3%, 2.3–64%), with
P=0.007. The relative concentration of maternal DNA in fetal blood was not affected by preeclampsia. These findings indicate that cell-free DNA is unequally transferred through the placenta. The structural characteristics of the placenta suggest that the majority of cell-free fetal DNA in maternal plasma is derived from villous trophoblasts. 相似文献