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

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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.