Abstract

Water extracts of Onopordum cynarocephalum (Oc) and Achillea damascena(Ad), traditionally used in Lebanon to treat various medical conditions including inflammatory diseases, were evaluated for anti-inflammatory activities employing an in vitro model of endotoxin (ET)-induced inflammation in mammary epithelial SCp2 cells and an in vivo model of ET-induced paw edema in male rats. Initially, both extracts inhibited the activity of fetal bovine serum derived gelatinase A and B in a concentration-dependent manner. In SCp2 cells, water extracts of Oc andAd at non-cytotoxic concentrations of 0.5% and 1%, respectively, decreased the expression of ET-induced inflammation markers interleukin-6 (IL-6) protein and mRNA, as well as gelatinase A and B activity via NF-κB. Furthermore, mRNA and protein levels of β-casein, an SCp2 differentiation marker, were suppressed 48 h post ET-stimulation and were not reversed by either of the plant extracts. In the in vivo model intraperitoneally injected water extracts of Oc or Ad in rats resulted in significant reduction of ET-induced paw edema starting at 12 and 8 h respectively. This new insight into the Oc and Ad mode of action contribute towards a better understanding of the claimed anti-inflammatory activities reported in folk medicine literature.

Key words: Inflammation, IL-6, gelatinases, NF-κB, mammary cells,Onopordum cynarocephalum, Achillea damascena.