Evaluation of General Toxicity and Genotoxicity of the Silkworm Extract Powder

The silkworm extract powder contain 1-deoxynojirimycin (DNJ), a potent alpha-glycosidase inhibitor, has therapeutic potency against diabetes mellitus. Therefore, natural products containing DNJ from mulberry leaves and silkworm are consumed as health functional food. The present study was performed to evaluate the safety of the silkworm extract powder, a health food which containing the DNJ. The repeated toxicity studies and gentic toxicity studies of the silkworm extract powder were performed to obtain the data for new functional food approval in MFDS. The safety was evaluated by a single-dose oral toxicity study and a 90 day repeated-dose oral toxicity study in Sprague-Dawley rats. The silkworm extract powder was also evaluated for its mutagenic potential in a battery of genetic toxicity test: in vitro bacterial reverse mutation assay, in vitro chromosomal aberration test, and in vivo mouse bone marrow micronucleus assay. The results of the genetic toxicology assays were negative in all of the assays. The approximate lethal dose in single oral dose toxicity study was considered to be higher than 5000 mg/kg in rats. In the 90 day study, the dose levels were wet at 0, 500, 1000, 2000 mg/kg/day, and 10 animals/sex/dose were treated with oral gavage. The parameters that were monitored were clinical signs, body weights, food and water consumptions, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, organ weights, and histopathological examination. No adverse effects were observed after the 90 day administration of the silkworm extract powder. The No-Observed-Adverse-Effect-Level (NOAEL) of silkworm extract powder in the 90 day study was 2000 mg/kg/day in both sexes, and no target organ was identified.

Uterine Adenomyosis in Beagle Dogs / 한국실험동물학회지

Adenomyosis is a nonneoplastic hyperplastic lesion, characterized by invagination of proliferating endometrial glands into myometrium. In dogs, uterine adenomyosis is relatively rare and it is important in Toxicologic Pathology to differentiate other non-neoplastic and neoplastic lesions in uterus. In the present study, we report two cases of adenomyosis in the female beagle dogs used for a chemical toxicity test. Clinically, one out of the two female beagle dogs, 15 months of age, had vaginal bleeding for 2 weeks and the other one, 11 months of age, showed swelling of vulva for a week. At necropsy, the weight of uterus was markedly increased to 27.9 g and 15.8 g, compared with the mean value (4.01+/-2.37, n=6) of that of other normal dogs, respectively. The parameters of hematology and serum chemistry were ranged normal in both of the dogs with enlarged uterus. For differentiation of connective tissue with muscle fibers, Van Gieson stain was also performed in the serial tissue sections. Histopathologically, the lesions of the enlarged uteruses were characterized by proliferating endometrial glands into myometrium, surrounded by connective tissue. The endometrial glands were proliferating downward to myometrium or embedded in multiple clustered glands in deeper myometrium without compressing the adjacent muscle fibers. The gland epithelial cells are uniformly cuboidal shape with a dense and bottom-located nucleus. These gross and histological findings were consistent with adenomyosis.