Effets des extraits de Pistacia lentiscus L. sur l’activité de l’élastase et sur le chimiotactisme des neutrophiles humains activés

Abstract

The medicinal plants with their anti-inflammatory properties are used to avoid the many undesirable effects which are associated with synthetic anti-inflammatory drugs. Many investigations clearly indicated that the anti-inflammatory activities of plants could be attributed to their contents in polyphenols and flavonoids. In this study, the content, in polyphenols and flavonoids, was estimated for the methanolic extracts (E-Met) of leaves and fruits with the aqueous extract (E-AQ) of leaves of Pistacia lentiscus. The results demonstrated that extracts had a high content in phenolic compounds and flavonoids. In addition, the anti-inflammatory effect of P. lentiscus extracts, particularly chemotaxis was evaluated in vitro on human neutrophils which were activated by fMLP. Our results showed that E-AQ and E-Met of leaves inhibited the chemotaxis response with an IC50 of 34.6± 0.5 and 26.7± 0.7µg/ml, respectively. However, the E-Met of fruits showed the highest anti chimiotactic effect with an IC50 of 19.8± 0.8µg/ml. Moreover, the inhibition effect of these extracts on elastase activity was evaluated. Both E-AQ and E-Met of leaves and E-Met of fruits extracts at 100µg/ml exhibited a high elastase inhibitory effect which was estimated by 82% 90% and 94%, respectively. In fact, that makes it possible to prove that E-Met of both leaves (IC50 of 11.5± 0.2µg/ml) and fruits (IC50 of 10.7 ± 0.7µg/ml) presented an important inhibition. Meanwhile, aqueous extract of the leaves showed a moderate anti-elastasic effect (IC50 de13.7± 0.4µg/ml). In conclusion, P. lentiscus, and especially its fruits, have an important anti-chimiotactic and anti-elastase capacities. Indeed, this plant can be considered as a natural source of the bioactive molecules which support it traditional use.