In vitro investigation of estrogenic activity of extracts and pure compounds obtained from the aerial parts of Glycyrrhiza glabra

The roots of Glycyrrhiza glabra (Leguminosae), which is a plant with rich ethnobotanical tradition, are used as a folk medicament both in Europe and in eastern countries, particularly China, where it is found in the Official Pharmacopoeia. [1] However, recent studies on the aerial parts of the plant of this genus have highlighted the antimicrobial and anti-HIV properties of their extracts, ascribable to flavonoids and bibenzylic compounds, respectively [2].

We investigated the dichloromethane (GG_DCM) and methanol (GG_M) extracts of the aerial parts of Glycyrrihza glabra (Leuguminosae, collected at Kefalonia, Greece) concerning their estrogenic activity in Ishikawa cells, HEKβ and MCF7 cells. In this research, the GG_DCM extract exhibited partial estrogenic activity as indicated by induction (50.8%) of AlkP (alkaline phosphatase) in cultured Ishikawa cells. In the contrast, the GG_M extract displayed a super estrogen-like activity (102%) at a concentration of 1µM.

Based on the aforementioned results, we isolated the phenolic compounds from these extracts by chromatographic methods of separation, i.e. CC, prep-TLC. The GG_DCM extract of the aerial parts of the plant contained two new flavanones derivatives, along with five known flavanones and two known dihydrostilbene derivaties which were identified also in same as the methanol extract. At least another four known metabolites have been isolated from methanol extract. Finally, we also evaluated the pure isolated compounds for the estrogenic or antiestrogenic activity in the same cells lines.

Acknowledgements: The project is co-funded by the 'Lavipharm' Group of Companies in the frames of program 'Intarnational collaboration in the industrial research and activities of growth in pre-competitive stage'

References: 1. Sibata S. (2000) Pharmaceutical Society of Japan, „A drug over the millennial: Pharmacognosy, chemistry and pharmacology of licorice“ Tokyo. 120:849–862

2. Nomura, T. et al. (2002) Pure Appl. Chem. 74:1199–1206.

References: 1. Sibata S. (2000) Pharmaceutical Societ of Japan, „A dug over the millennial: Pharmacognosy, chemistry and pharmacology of licorice“ Tokyo. Vol.120:849–862

2. Nomura T., et al. (2002) Pure Appl. Chem. Vol.74:1199–1206.