We previously reported that sugar levels in the silkworm hemolymph, i.e., blood, increase immediately (within 1 h) after intake of a high-glucose diet, and that the administration of human insulin decreases elevated hemolymph sugar levels in silkworms. In this hyperglycemic silkworm model, however, administration of pioglitazone or metformin, drugs used clinically for the treatment of type II d...

Silkworm has been proposed recently as an animal model for the study of therapeutic effects of drug candidates. Little is known regarding the factors influencing the physiology of the silkworm, and this might become the major effect of the therapeutic result interpretation. In the present study, the effect of a diet of mulberry leaves as compared to an artificial diet on Thai silkworm growth de...

BACKGROUND We use silkworms to evaluate therapeutic effects of drug candidates. Our previous reports have revealed that there are common mechanisms of pharmacokinetics of chemicals in silkworms and mammals. In this report, we attempt to establish a method by using silkworms to identify chemicals from plant extracts which are absorbed from intestine and also stably exist in body fluids. RESULT...

We have used silkworms, larva of Bombyx mori, to investigate host-pathogen interactions. Silkworms have several advantages, such as high availability of a large number of animals and ease of injection of quantitative amounts of samples. Human pathogenic bacteria such as Staphylococcus aureus, Streptococcus pyogenes, or Pseudomonas aeruginosa kill silkworms. In this review, I would like to summa...

We developed a method to predict bacterial pathogenicity against mammals by measuring bacterial virulence in silkworms at 37°C, human body temperature. One hundred and twenty-two strains of bacteria were isolated from the intestines of fish and shellfish and tested for their virulence against silkworms. Overnight cultures of 50 strains killed at least 50% of the silkworms when injected into the...

To investigate the influence of low-dose-rate irradiation on the growth of silkworms, Bombyx mori, eggs of silkworms were randomly divided into 2 groups and were grown on either low-dose-radiation-emitting sheets or control sheets. On the radiation-emitting sheets, the dose rate was measured as 66.0 (4.3) μSv/h (mean [standard deviation]) by a Geiger-Müller counter for α, β, and γ rays and 3.8 ...

Injection of a Japanese cedar pollen suspension into silkworm hemolymph kills the silkworms. A certain species of bacteria proliferated in the hemolymph of the dead silkworms. A 16S rDNA analysis demonstrated that the proliferating bacteria were Bacillus cereus, Bacillus thuringiensis, Bacillus weihenstephanensis, and Bacillus amyloliquefaciens. Among them, B. cereus, B. thuringiensis, and B. w...

This study was conducted out to select a silkworm variety suitable for synnemata production of Isaria tenuipes. Four kinds of the mulberry silkworm varieties, Bombyx mori, were hybridized using a Japanese parental line and a Chinese parental line, and used to test for synemata formation in I. tenuipes. The larval period of normal silkworms was 22 hr longer than the silkworms inoculated with thi...

Silkworms are invertebrate animals that are killed by bacteria pathogenic against humans, such as Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa, and Vibrio cholerae. Injection into the hemolymph of antibiotics that are clinically used for human patients abolishes the killing effects. There are several advantages to using silkworms as an infection model, such as low cost,...