Relationship between antiproliferative and antioxidant activity of two extracts from Tilia x viridis on normal and tumoral lymphocytes

M RODRIGUEZ BRIZI; C MARRASSINI; G ZETTLER; G FERRARO; C ANESINI

Sitges, Barcelona

Conferencia; 5th INternational Conference on Polyphenols ansd Health; 2011

Universidad de Barcelona

Tilia species have been used to treat anxiety, colds, influenza, bronchitis, fever, and inflammation.  Previously it was demonstrated that a dichloromethane extract from Tilia x viridis, widely used and distributed in Argentina, presents antiproliferative action on a lymphoma cell line. It is well established that oxygen reactive species (ROS) principally hydrogen peroxide (H2O2) and the superoxide anion (O2.-), are involve in normal and pathological modulation of proliferation/death cellular balance. It is known that lymphocytes play a role in acquired immunity related to pathogens and tumorous cells attached. It was reported the presence of flavonoids in Tilia species which have antioxidant properties. The aim of this study was to determine the effect of an aqueous (AE) and a ethanol (E) extract from Tilia x viridis, on the proliferation of tumoral and normal concanavalin A stimulated murine lymphocytes in relation to antioxidant activities involves in H2O2 modulation. Also a phytochemical pattern of the two extracts in relation to flavonoids content was assayed. The proliferation was determined by tritiated thymidine uptake, inhibition of linoleic acid peroxidation, superoxide dismutase (SOD) and catalase (CAT) “per se“activities were determined by spectrometric methods. Also, were determined by spectrophotometry the polyphenol content and the majority flavonoids by HPLC. Both extracts presented antiproliferative action on both type of lymphocytes (effective medium concentration EC50 (µg/ml), mean ±SEM, three experiments made by triplicate) tumoral lymphocytes:  E: 50 ± 4, AE: 4500 ± 300; normal lymphocytes: E: 323 ± 20, AE: 501 ± 30). E was more selective on the tumoral lymphocytes inhibition in relation to a high polyphenol content (150 ± 10 mgGAE/g extract), antioxidant activity and rutin presence. Therefore the extracts could be a source of antioxidant compounds which contribute to a selective antiproliferative action on tumoral cells, acting by modulation of H2O2 levels.