Inhibition of ICAM-1 expression and elastase by an extract and fractions from the roots of Ruscus aculeatus
Extracts from Butcher's broom (Ruscus aculeatus) are known to be effective in the treatment of oedema, haemorrhoids and chronic venous insufficiency (CVI) . Several reports suggested microangiopathic changes as one of the main problems for the development of CVI. Furthermore enzymes like elastase and hyaluronidase are involved in breakdown of protein within the capillary walls, which in turn leads to swelling and CVI associated skin changes.
Powdered roots of R. aculeatus (Convallariaceae) were extracted with methanol and the extract was distributed between water and 1-butanol. Inhibition of ICAM-1 expression by the methanol extract was studied in the Human Microvascular Endothelial Cell line (HMEC-1). The methanol extract as well as resultant fractions from distribution were tested for elastase inhibition.
TNF-α induced ICAM-1 expression was decreased by the methanol extract to 80% at 1µg/mL. This effect was not related to cytotoxicity due to the fact that this extract showed no cytotoxic effect on the HMEC-1 in the MTT viability assay up to a concentration of 1000µg/mL. In the elastase inhibition assay, the extracts and its fractions showed activity with the 1-butanol fraction being the most active exhibiting IC50 value at 4µg/mL. TLC analysis revealed that the butanol-1 phase contain the majority of the steroid saponins.
Acknowledgements: Thanks are due to Dr. E. Ades and Mr. F. J. Candal of CDC (USA) and Dr. T. Lawley of Emory University (USA) for providing us the HMEC-1 cells.
References: 1. Thorne (2001) Alternative Medicine Review 6:608–612.