著者
Akiho Yagi Hiroyuki Yamazaki Takeshi Terahara Taehui Yang Hiroshi Hamamoto Chiaki Imada Hiroshi Tomoda Ryuji Uchida
出版者
International Research and Cooperation Association for Bio & Socio-Sciences Advancement
雑誌
Drug Discoveries & Therapeutics (ISSN:18817831)
巻号頁・発行日
vol.14, no.6, pp.287-295, 2020-12-31 (Released:2021-01-23)
参考文献数
31
被引用文献数
5

In vivo-mimic silkworm infection models with Mycobacterium avium and Mycobacterium intracellulare were newly established to evaluate the therapeutic effects of anti-M. avium complex (MAC) antibiotics. Silkworms raised at 37°C died within 72 hours of an injection of M. avium or M.intracellulare (2.5 × 107 colony-forming unit (CFU)/larva·g) into the hemolymph. Clinical anti-mycobacterial (tuberculosis) antibiotics were evaluated under these conditions. Clarithromycin, kanamycin, streptomycin, amikacin, and ciprofloxacin exerted therapeutic effects in a dose-dependent manner, which was consistent with those in the mouse model. Furthermore, three effective actinomycete culture broths were selected in the screening program of our microbial broth library using the silkworm model, and four active metabolites, ohmyungsamycins A and B (1 and 2), chartreusin (3), and griseoviridin (4), were identified. Among these compounds, 1 showed the lowest 50% effective dose (ED50) value (8.5 µg/larva·g), while 3 had the best ED50/minimum inhibitory concentration (MIC) ratio (7.4). These results indicate that silkworm models are a useful tool for identifying anti-MAC antibiotics candidates with veritable therapeutic effects.
著者
Magie Melanie Kapojos Delfly Booby Abdjul Hiroyuki Yamazaki Akiho Yagi Ryuji Uchida
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.68, no.9, pp.903-906, 2020-09-01 (Released:2020-09-01)
参考文献数
14
被引用文献数
1

Bioassay screening using Indonesian plants, such as traditional foods (vegetables, spices, and tea) and folk medicinal herbs, identified eight protein tyrosine phosphatase (PTP) 1B inhibitory and two antibacterial plants. The leaves of Syzygium polyanthum (Wight) Walp. were examined in more detail to define PTP1B inhibitory components, resulting in the isolation of a new active acylbenzene (1) along with four related congeners of 1 (2–5) and four oleanane triterpenes (6–9). The structure of 1 was elucidated as 12-oxo-12-(2,3,5-trihydroxy-4-methylphenyl)dodecanoic acid based on its spectroscopic data. The acylbenzenes 1 and 3–5 inhibited PTP1B activity with IC50 values ranging between 9.5 and 14 µM, whereas the triterpenes 7–9 also suppressed this activity with IC50 values of 3.3–5.7 µM.
著者
Akinori Shintani Hiroyuki Yamazaki Yukinori Yamamoto Firoj Ahmed Masami Ishibashi
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.57, no.8, pp.894-895, 2009-08-01 (Released:2009-08-01)
参考文献数
9
被引用文献数
7 11

Chemical investigation of field-collected fruit bodies of the myxomycete Cribraria meylanii resulted in the isolation of a naphthoquinone pigment, cribrarione C, and its structure was elucidated by spectral data as 2,5,6,7-tetrahydroxy-1,4-naphthoquinone (1). This compound (1) had been synthesized previously, while it was isolated here for the first time as a natural product, and its NMR and MS data are described in this study.