Cellular proliferation and wound healing activity induced by purified fractions from Sempervivum tectorum L.

In recent years, interest has increased in obtaining drugs from those plants with high content of bioactive substances like triterpenes, alkaloids, tannins and flavonoids for their potential use in promoting wound healing. Sempervivum tectorum L. (Crassulaceae), known as houseleek, is a evergreen plant which grows in central and southern Europe. Fresh juice or squeezed leaves are used in folk medicine exclusively for external purposes in the treatment of the ear inflammation, for wound, sores and abscesses as refrigerant and astringent [1]. Antinociceptive and antioxidant [2] activity, in vivo and in vitro model, was also investigated. The present study was undertaken with the aim to explore the biological activity of the extracts and of the purified fractions of Sempervivum tectorum L. leaves. The extract is rich in free sugars with the rare sedoheptulose, organic acids such as malic acid, flavonoids and 2-C-methyerithritol. We analyzed the effects of Sempervivum tectorum purified fractions on cellular proliferation and migration [3] in HCT cells. We observed that treatment with the fractions with high level of sedoheptulose and malic acid of Sempervivum tectorum (SVT high fraction), significantly improved cellular migration and proliferation. We next investigated on the intracellular signaling cascades triggered by the incubation with the SVT high fraction and we observed that incubation with the SVT high fraction induces a significant phosphorylation of EGFR and Src. Furthermore, HCT cells stimulated with the SVT high fraction show a significant increase of STAT3 phosphorylation and this event was prevented by AG1478, an EGFR selective inhibitor. Taken together these data strongly suggest that the SVT high fraction significantly improve cellular proliferation and migration by inducing a Src-dependent EGFR activation and might represent a new proliferative and new wound healing therapeutic approaches.