Environ Health Toxicol.  2018 Sep;33(3):e2018016. 10.5620/eht.e2018016.

Ginkgo biloba extract (EGb761) did not express estrogenic activity in an immature rat uterotrophic assay

• Moon B
• Kim W
• Park CH
• Oh SM

• KMID: 2434041
• DOI: http://doi.org/10.5620/eht.e2018016

Abstract

Ginkgo biloba is a dioecious tree that has been used in traditional Chinese medicine for about 5,000 years. In previous studies on Ginkgo biloba extract (EGb761) using in vitro systems, we confirmed that EGb761 has biphasic effects on estrogenicity. In this study, we evaluated the agonistic and antagonistic activities of EGb761 using a uterotrophic assay in immature female rats. To evaluate agonistic and antagonistic effects of EGb761 on uterus, 21-day-old immature Sprague-Dawley (SD) female rats were treated with EGb761 (100, 200, or 400 mg/kg) by oral gavage, 10 μg/kg of estradiol (E2) or 1 mg/kg tamoxifen (TM) by subcutaneous injection, or with EGb761 plus E2 or TM for 3 consecutive days. At the end of the treatment period, animals were sacrificed and their body weights and organ weights (liver, lung, spleen and kidney) were measured. In addition, estrogen-related gene expressions (IGFBP-1 in liver and CaBP-9 in uterus) were determined. During the experiment, no animal showed clinical signs, a change in body weight or died. EGb761 treatment alone had no effect on absolute/relative uterine weight, luminal epithelial cell height (LECH, μm), or luminal circumference (LC, μm). In addition, uterine weights, LECHs, and LC induced by E2 or TM were not significantly changed by EGb761 at any dose. These results collectively suggested EGb761 has no agonistic/antagonistic effects in utero.

Keyword

Ginkgo biloba extract; EGb761; uterus; uterotrophic assay

MeSH Terms

Animals
Body Weight
Epithelial Cells
Estradiol
Estrogens*
Female
Gene Expression
Ginkgo biloba*
Humans
In Vitro Techniques
Injections, Subcutaneous
Liver
Lung
Medicine, Chinese Traditional
Organ Size
Phenobarbital
Rats*
Rats, Sprague-Dawley
Spleen
Tamoxifen
Trees
Uterus
Weights and Measures
Estradiol
Estrogens
Phenobarbital
Tamoxifen