GC-MS profiling of the phytochemical constituents of the oleoresin from Copaifera langsdorffii Desf. and a preliminary in vivo evaluation of its antipsoriatic effect.

Copaiba is the oleoresin (OR) obtained from Copaifera (Fabaceae), a neotropical tree which grows in Amazon regions. The balsam, constituted by an essential oil and a resinous fraction is used as folkloristic remedy in the treatment of several inflammatory diseases and for its antioxidant and antibacterial properties. Aim of this work was (a) to carry out a characterization by GC-MS of the volatile and nonvolatile constituents of Copaifera langsdorffii Desf. oleoresin (OR); (b) to investigate the mechanism of its anti-inflammatory activity; (c) to evaluate its antipsoriatic effect after oral intake/topical application. The volatile fraction (yield: 22.51%, w/w) shows: α-bergamotene (48.38%), α-himachalene (11.17%), β-selinene (5.00%) and β-caryophyllene (5.47%). The OR residue (77.49%, w/w), after derivatization, showed as main constituents the following compounds: copalic, abietic, daniellic, lambertinic, labd-7-en-15-oic, pimaric, isopimaric acids and kaur16-en18-oic acid. Preincubation of LPS-stimulated human THP-1 monocytes with increasing concentrations of the OR purified fraction (OR-PF), containing diterpene acids, diterpenes and sesquiterpenes, reduced the release of pro-inflammatory cytokines (IL-1β, IL-6, TNFα) in a dose-range of 0.1-10 μM. In addition, in cell culture system of human THP-1 monocytes, 1 μM OR-PF counteracts LPS-driven NF-κB nuclear translocation. In a preliminary clinical trial three patients affected by chronic psoriasis, treated with oral intake or topical application of the OR, exhibited a significant improvement of the typical signs of this disease, i.e. erythema, skin thickness, and scaliness. In conclusion, the results of this work, beside an extensive analytical characterization of the OR chemical composition, provide strong evidences that its anti-inflammatory activity is related to the inhibition of the NF-κB nuclear translocation, and consequently of proinflammatory cytokines secretion.