Evaluation of anti-estrogenic or estrogenic activities of aqueous root extracts of Gunnera manicata L.

Abstract

Gunnera perpensa (Gunneraceae) is an African plant widely used in traditional medicine. This species is known for its activity involving the female reproductive system, such as inducing or increasing labor, treating female infertility, expelling the placenta and/or preventing post-partum hemorrhage. These properties are probably due to (z)-venusol, a majoritary compound, and its action in conjunction with substances in the whole extract and other natural products. In southern Brazil, a native species Gunnera manicata L. that also belongs to Gunneraceae can be found. In spite of the traditional use of G. perpensa, there is no pharmacological and phytochemical information regarding the South American Gunnera species. Therefore, the aim of this study was to investigate the activity of Brazilian G. manicata aqueous extracts on the reproductive system of immature female Wistar rats through a uterotrophic assay and to verify the presence of (z)-venusol by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Data were analyzed by analysis of variance (ANOVA) and Bonferroni's post-hoc test (p< 0.01). Results obtained shown that G. manicata extracts did not present in vivo anti or estrogenic activity. Furthermore, (z)-venusol compound was not found. This study represents the first preliminary screening done on the South American G. manicata species.