Evaluation of anti-inflammatory-related activity of essential oils from the leaves and resin of species of Protium

The resins and leaves of species of Protium are commonly used by folk medic ine. In the present study, we analyse the pharmacological effects of essent ial oils obtained by steam distillation (leaves and resin) from Protium spe cies. Analysis by gas chromatography (GC) coupled to mass spectrometry and retention indices calculations demonstrate that the resin oil is constitute d mainly of monoterpenes and phenylpropanoids: alpha-terpinolene (22%), p-c ymene (11%), p-cimen-8-ol (11%), limonene (55) and dillapiol (16%), whereas sesquiterpenes predominate as the volatile constituents of the leaves. The resin of Protium heptaphyllum (PHP) and leaves of P. strumosum (PS), P. gr andifolium (PG), P. lewellyni (PL) and P. hebetatum (PHT) were screened for anti-inflammatory activity by the use of mouse pleurisy model induced by z ymosan (500 mu g/cavity) and lipopolysaccharide (LPS) (250 ng/cavity), for antinociceptive effect (by means of preventing mice abdominal writhings), a s well as NO production from stimulated macrophages and proliferation of ne oplasic cell lines: Neuro-2a (mouse neuroblastoma), SP2/0 (mouse plasmocyto ma) and J774 (mouse monocytic cell line). The oils from PHP, PS and PL were able to inhibit protein extravasation but no sample inhibited total or dif ferential leucocyte counts after administrating p.o. (100 mg/kg) 1 h before stimulation with zymosan. The oils from PG, PL and PHT inhibited neutrophi l accumulation whereas PHP and specially PL inhibited LPS-induced eosinophi l accumulation in mouse pleural cavity. PHT was also able to inhibit mononu clear cells accumulation. Antinociceptive effect was not observed, when ani mals received oral administration of the essential oils (100 mg/kg). In vit ro treatment with essential oils (100 mu g/well) changed the NO production from stimulated mouse macrophages. PHP inhibited in 74% and PS in 46% the L PS-induced NO production. In contrast, treatment with PL was able to increa se in 49% the NO production. Cell lines proliferation was affected by the o ils assayed in the range of 60-100% for Neuro-2a, 65-95% for SP2/0 and 70-9 0% for J774. Taken together these results showed that essential oils could be useful as efficient pharmacological tools. (C) 1999 Elsevier Science Ire land Ltd. All rights reserved.