Anti-inflammatory and anti-allergic properties of the essential oil and active compounds from Cordia verbenacea

The anti-inflammatory and anti-allergic effects of the essential oil of Cordia verbenacea (Boraginaceae) and some of its active compounds were evaluated. Systemic treatment with the essential oil of Cordia verbenacea (300–600 mg/kg, p.o.) reduced carrageenan-induced rat paw oedema, myeloperoxidase activity and the mouse oedema elicited by carrageenan, bradykinin, substance P, histamine and platelet-activating factor. It also prevented carrageenan-evoked exudation and the neutrophil influx to the rat pleura and the neutrophil migration into carrageenan-stimulated mouse air pouches. Moreover, Cordia verbenacea oil inhibited the oedema caused by Apis mellifera venom or ovalbumin in sensitized rats and ovalbumin-evoked allergic pleurisy. The essential oil significantly decreased TNFα, without affecting IL-1β production, in carrageenan-injected rat paws. Neither the PGE2 formation after intrapleural injection of carrageenan nor the COX-1 or COX-2 activities in vitro were affected by the essential oil. Of high interest, the paw edema induced by carrageenan in mice was markedly inhibited by both sesquiterpenic compounds obtained from the essential oil: α-humulene and trans-caryophyllene (50 mg/kg, p.o.). Collectively, the present results showed marked anti-inflammatory effects for the essential oil of Cordia verbenacea and some active compounds, probably by interfering with TNFα production. Cordia verbenacea essential oil or its constituents might represent new therapeutic options for the treatment of inflammatory diseases.