Quantitative evaluation of the therapeutic effects of antibiotics using silkworms infected with human pathogenic microorganisms.
The injection of bacteria (Staphylococcus aureus, Stenotrophomonas maltophilia) or true fungi (Candida albicans, Candida tropicalis) that are pathogenic to humans into the silkworm hemolymph leads to death of the larvae within 2 days. Antibiotics used for clinical purposes have therapeutic effects on silkworms infected with these pathogens. The 50% effective doses obtained by injection into the silkworm hemolymph are consistent with those reported for mice. Injection of vancomycin and kanamycin into the silkworm hemolymph was effective, but oral administration was not. Chloramphenicol, which is effective by oral administration, appeared in the silkworm hemolymph soon after injection into the midgut, whereas vancomycin did not. Isolated midgut membranes were impermeable to vancomycin. Thus, the ineffectiveness of oral administration of vancomycin to silkworms is due to a lack of intestinal absorption.
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Hiroshi
H
Hamamoto
Kenji
K
Kurokawa
Chikara
C
Kaito
Koushirou
K
Kamura
Iony
I
Manitra Razanajatovo
Hiroyuki
H
Kusuhara
Tomofumi
T
Santa
Kazuhisa
K
Sekimizu
D000284:Administration, Oral; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology*; D012831:Bombyx / Q000382:microbiology*; D002462:Cell Membrane / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006458:Hemolymph / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007273:Injections, Intramuscular
D000900:Anti-Bacterial Agents