'Echinacea' alkylamides modulate induced immune responses in T-cells

Abstract

The effects of 'Echinacea' and several of its phytochemical components on NFkB expression by Jurkat cells (a human T-cell line) were investigated 'in vitro'. In the absence of stimulation, 'Echinacea' and its components exerted no significant effect on basal NFkB expression levels. In the presence of endotoxin (LPS), NFkB expression was decreased. However, this decrease was significantly reverssed by treatment with cichoric acid, an 'Echinacea' root extract (prepared from both 'Echinacea angustifolia' and 'Echinacea purpurea') and the alkylamide fraction derived from this combination. For the phorbol myristate acetate stimulation of Jurkat cells, effects on NFkB levels were mixed. Depending on the concentration, cichoric acid and a 2,4-diene alkylamide significantly induced NFkB levels, whereas a 2-ene alkylamide caused a significant inhibition. In contrast, both the 'Echinacea' and the mixed alkylamide fraction exerted no effect. The alkylamide results indicate that the two basic forms of these compounds present in 'Echinacea' may have opposing effects. These opposing effects demonstrate the importance of a knowledge, not only of the phytochemical make-up of a herbal preparation, but also of the actions of each component and the consequences of differing relative amounts in the preparation being investigated.