Search

Your search keyword '"Shigemori, Hideyuki"' showing total 529 results
Start Over Author "Shigemori, Hideyuki"
529 results on '"Shigemori, Hideyuki"'

3. Bioactive Compounds Involved in the Life Cycle of Higher Plants

Author

Shigemori, Hideyuki, Kinghorn, A. Douglas, Series Editor, Falk, Heinz, Series Editor, Asakawa, Yoshinori, Series Editor, Liu, Ji-Kai, Series Editor, Appendino, Giovanni, Advisory Editor, Berlinck, Roberto G. S., Advisory Editor, Ludwiczuk, Agnieszka, Advisory Editor, Mata, Rachel, Advisory Editor, Oberlies, Nicholas H., Advisory Editor, Tasdemir, Deniz, Advisory Editor, Trauner, Dirk, Advisory Editor, Viljoen, Alvaro, Advisory Editor, Ye, Yang, Advisory Editor, Gibbons, Simon, editor, and Kobayashi, Jun'ichi, editor

Published
2019
Full Text
View/download PDF

10. Three new meroterpenoids from Sargassum macrocarpum and their inhibitory activity against amyloid β aggregation.

Author

Shinoda, Seiya, Tozawa, Yuta, Kurimoto, Shin-ichiro, Shigemori, Hideyuki, and Sekiguchi, Mitsuhiro

Abstract

Amyloid β (Aβ) is thought to be involved in the pathogenesis of Alzheimer's disease (AD). Aβ aggregation in the brain is considered the cause of AD. Therefore, inhibiting Aβ aggregation and degrading existing Aβ aggregates is a promising approach for the treatment and prevention of the disease. In searching for inhibitors of Aβ42 aggregation, we found that meroterpenoids isolated from Sargassum macrocarpum possess potent inhibitory activities. Therefore, we searched for active compounds from this brown alga and isolated 16 meroterpenoids, which contain three new compounds. The structures of these new compounds were elucidated using two-dimensional nuclear magnetic resonance techniques. Thioflavin-T assay and transmission electron microscopy were used to reveal the inhibitory activity of these compounds against Aβ42 aggregation. All the isolated meroterpenoids were found to be active, and compounds with a hydroquinone structure tended to have stronger activity than those with a quinone structure. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

34. Inhibitory Effects of Polyacetylene Compounds from Panax ginseng on Neurotrophin Receptor-Mediated Hair Growth

Author

Suzuki, Aoi, Matsuura, Daisuke, Kanatani, Hirotoshi, Yano, Shingo, Tsunakawa, Mitsuo, Matsuyama, Shigeru, and Shigemori, Hideyuki

Subjects
nervous system
Abstract

Neurotrophins play an important role in the control of the hair growth cycle. Therefore, neurotrophin receptor antagonists have therapeutic potential for the treatment of hair growth disorders. In this study, we investigated the inhibitory effect of Panax ginseng, a medicinal plant commonly used to treat alopecia, on the binding of neurotrophins to their receptors. In addition, we isolated and characterized the bioactive compounds of P. ginseng extracts. P. ginseng hexane extracts strongly inhibited brain-derived neurotrophic factor (BDNF)-TrkB and β-nerve growth factor (β-NGF)-p75 neurotrophin receptor (p75NTR) binding. Furthermore, we identified the following 6 polyacetylene compounds as the bioactive components in P. ginseng hexane extract: panaxynol (1), panaxydol (2), panaxydol chlorohydrin (3), 1,8-heptadecadiene-4,6-diyne-3,10-diol (4), panaxytriol (5), and dihydropanaxacol (6). In particular, compounds 4, 5, and 6 significantly inhibited BDNF-TrkB binding in a dose-dependent manner. To identify the structural component mediating the inhibitory effect, we investigated the effects of the hydroxyl moiety in these compounds. We found that the inhibitory effect of panaxytriol (5) was strong, whereas the inhibitory effect of Ac-panaxytriol (7) was relatively weak. Our findings suggest that P. ginseng-derived polyacetylenes with a hydroxyl moiety might provide therapeutic benefits to patients with hair growth disorders such as alopecia by inhibiting the binding of neurotrophins to their receptors. Although saponins have been proposed to be the primary mediators of the effects of P. ginseng on hair growth, this study revealed that polyacetylene compounds exert similar effects.

Published
2017

40. Subincanadines A-C, novel quaternary indole alkaloids from Aspidosperma subincanum

Author

Kobayashi, Jun'ichi, Sekiguchi, Mitsuhiro, Shimamoto, Sayaka, Shigemori, Hideyuki, Ishiyama, Haruaki, and Ohsaki, Ayumi

Subjects
Chemistry, Organic -- Research, Alkaloids -- Physiological aspects, Indole -- Physiological aspects, Chemical reactions -- Analysis, Spectrum analysis -- Usage, Biological sciences, Chemistry
Abstract

Research has been conducted on the quaternary indole alkaloids isolated from Aspidosperma subincanum Mart barks. The study of these alkaloids' structure and stereochemistry carried out via chemical means and spectrum analysis is presented.

Published
2002

42. Dictyonamides A and B, new peptides from marine-derived fungus

Author

Komatsu, Kazusei, Shigemori, Hideyuki, and Kobayashi, Jun'ichi

Subjects
Chemistry, Organic -- Research, Fungi -- Physiological aspects, Peptides -- Analysis, Biological sciences, Chemistry
Abstract

Research has been conducted on the marine-derived fungi. The isolation and structure elucidation of dictyonamides A and B are described.

Published
2001

45. Inhibitory Activities of Antioxidant Flavonoids from Tamarix gallica on Amyloid Aggregation Related to Alzheimer's and Type 2 Diabetes Diseases

Author

Ben Hmidene, Asma, Hanaki, Mizuho, Murakami, Kazuma, Kazuhiro Irie, Isoda, Hiroko, and Shigemori, Hideyuki

Subjects
fungi, mental disorders, food and beverages, heterocyclic compounds
Abstract

The prevention of amyloid aggregation is promising for the treatment of age-related diseases such as Alzheimer’s (AD) and type 2 diabetes (T2D). Ten antioxidant flavonoids isolated from the medicinal halophyte Tamarix gallica were tested for their amyloid aggregation inhibition potential. Glucuronosylated flavonoids show relatively strong inhibitory activity of Amyloid β (Aβ) and human islet amyloid polypeptide (hIAPP) aggregation compared to their aglycone analogs. Structure–activity relationship of the flavonoids suggests that the catechol moiety is important for amyloid aggregation inhibition, while the methylation of the carboxyl group in the glucuronide moiety and of the hydroxyl group in the aglycone flavonoids decreased it.

Published
2017

48. Metachromins D-H, new cytotoxic sesquiterpenoids from the Okinawan marine sponge Hippospongia metachromia

Author

Kobayashi, Jun'ichi, Naitoh, Kazushi, Sasaki, Takuma, and Shigemori, Hideyuki

Subjects
Sponges -- Research, Terpenes -- Analysis, Antineoplastic agents -- Research, Biological sciences, Chemistry
Abstract

The marine sponge H. metachromia yields five new antitumor sesquiterpenoids, metachromins D-H. Spectroscopic studies show that metachromins D (C24H34O5) andE (C22H28O4) are structurally identical to the known metachromin B, save for the C-19 methoxy for D and the benzoquinone moiety for E. The three terpenes have a 4R,6R,9S configuration. Metachromins F (C25H36O4), G (C29H37NO3) and H (C26H39NO3) are structurally identical to the known metachromin A, except for their functionalities at C-20 (butyloxy for F, phenylethylamino for G and isoamylamino for H vs methoxy for A). Like A, metachromins F-H have a 4R,6R configuration.

Published
1992

49. Alteramide A, a new tetracyclic alkaloid from a bacterium Alteromonas sp. associated with the marine sponge Halichondria okadai

Author

Shigemori, Hideyuki, Myung-Ae Bae, Yazawa, Kazanuga, Sasaki, Takuma, and Kobayashi, Jun'ichi

Subjects
Alkaloids -- Research, Amides -- Research, Sponges -- Research, Biological sciences, Chemistry
Abstract

The cultured mycelium of the Alteromonas sp. bacterium from the marine sponge Halichondria okadai yields a new cytotoxic alkaloid, alteramide A. Spectroscopic studies suggest a three-ring system with a molecular formula of C29H38N2O6, a macrocylic lactam with a dienone and a dienoyltetramic acid unit. In methanol solution, alteramide A undergoes photochemical (4 + 4) cycloaddition to form a hexacycle with the same molecular formula. Alteramide A exhibits in vitro cytotoxicity against murine leukemia P388 and lymphoma L1210 cells as well as human epidermoid carcinoma KB cells.

Published
1992

50. Luffariolides A-E, new cytotoxic sesterterpenes from the Okinawan marine sponge Luffariella sp

Author

Tsuda, Masashi, Shigemori, Hideyuki, Ishibashi, Masami, Sasaki, Takuma, and Kobayashi, Jun'ichi

Subjects
Terpenes -- Analysis, Sponges -- Research, Biological sciences, Chemistry
Abstract

The Okinawan marine sponge Luffariella sp. yields five new sesterterpenes, luffariolides A-E, along with the known (6E)- and (6Z)-neomanoalides. Spectroscopic studies reveal the structures of the new terpenes. Luffariolide A is an optically inactive structural cousin of (6E)-neomanoalide with an alpha, beta-unsaturated ester. Luffariolide B is a regioisomer of (6Z)-neomanoalide and has an R configuration at C-4. Luffariolide C is 2, 3-dihydro-(6Z)-neomanoalide with a 3R,4R configuration. Luffariolides D and E are neomanoalide analogues with alpha, beta-unsaturated delta- and gamma- lactones. All the sponge extracts exhibit cyctotoxicity against murine lymphoma L1210 cells in lab bioassays.

Published
1992

Catalog

Books, media, physical & digital resources
See catalog results