Abstract
Caffeic acid phenethyl ester (CAPE) is an antioxidant component of propolis, a natural product secreted by honeybee. Recent literature shows that CAPE inhibits nuclear factor k B (NFkB) activation in cell lines. Since NFkB was shown to be a crucial factor in neuroinflammation and to be assocd. with some neuropathologies, CAPE might reduce these disorders in brain too and have therapeutic applications. To test this hypothesis we used a model of endotoxic insult (interferon-g, followed by lipopolysaccharide) on rat organotypic hippocampal cultures. Cerebral inflammatory responses were strongly inhibited by CAPE (100 mM): redns. of NFkB nuclear activity, tumor necrosis factor a and nitric oxide productions were obsd. At the dose of maximal effects (100 mM), an increase of cAMP-responsive element binding protein (CREB) activity, which anti-inflammatory role is well known, was seen. We compared CAPE effects with those of other drugs: anti-inflammatory as acetylsalicylate and dexamethasone (glucocorticoid), antioxidant as pyrrolidine dithiocarbamate, or selective permeant inhibitor of NFkB as SN 50 peptide. These studies lead us to conclude that CAPE presents an interesting and original neuropharmacol. profile compared to these drugs and might be helpful in the prevention of neurotoxic events due to excessive inflammatory reaction in brain. CAPE interferes with several effectors of neuroinflammation that might have complementary and synergic effects and allows a rather durable control since an acute treatment at the time of endotoxin exposure allows to control inflammatory factors for over 48 h. [on SciFinder (R)]