Characterization of the estrogenic response to genistein in Japanese medaka (Oryzias latipes)
| Autor: | Ikhlas A. Khan, Luling Zhang, Christy M. Foran |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Male
medicine.medical_specialty Physiology Health Toxicology and Mutagenesis Oryzias Blotting Western Genistein Enzyme-Linked Immunosorbent Assay Biology Toxicology Biochemistry Vitellogenins chemistry.chemical_compound Vitellogenin Internal medicine Testis medicine Animals Endocrine system Testosterone Dose-Response Relationship Drug Estradiol Ovary Cell Biology General Medicine Japanese Medaka biology.organism_classification Hydroxycholesterols Endocrinology Liver chemistry biology.protein Female hormones hormone substitutes and hormone antagonists Ex vivo Corn oil |
| Zdroj: | Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology. 132:203-211 |
| ISSN: | 1532-0456 |
| DOI: | 10.1016/s1532-0456(02)00067-4 |
| Popis: | This study was designed to determine the estrogenic effect of the phytoestrogen genistein on several measures of endocrine function in adult Japanese medaka (Oryzias latipes) relative to 17-beta-estradiol. Adult animals of both sexes were exposed to 75, 750 and 30,000 ng/fish (average fish weight equals 0.26 g) of genistein by i.p. injection, with a positive control group treated with 300 ng/fish of 17-beta-estradiol, while a negative control group received a vehicle-only (corn oil) injection. Content of vitellogenin, the yolk glycoprotein made in the liver in response to estradiol stimulation, was measured using Western blots. Circulating estradiol and testosterone levels were measured using a steroid-enzyme immunosorbant assay. The ability of ovaries and testes to synthesize and release estradiol and testosterone was determined by ex vivo incubation of gonads with 25-hydroxycholesterol. Vitellogenin, while induced by 17-beta-estradiol, was not increased in the liver of individuals treated with genistein. In females, genistein treatment at 750 and 30,000 ng increased the estradiol production of ovaries more than the 17-beta-estradiol treatment. In males, genistein treatment resulted in decreased testosterone production from ex vivo testis and a comparable reduction in circulating testosterone level. The changes in vitellogenin, circulating steroids and ex vivo steroidogenesis in medaka in response to genistein are similar to that of 17-beta-estradiol. However, some endpoints are more sensitive to estradiol treatment (vitellogenin), while others are more sensitive to genistein (male testosterone and ovarian estrogenesis). |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect