Study of the Modulation of Cytokine Release by Natural Compounds with Pharmacological Properties Using Cell-Based Systems

Background: The screening of the pharmacological properties of natural compounds (i.e., anti-inflammatory effects) may take advantage of some specific cell-based systems. Parthenolide (PTN) and Copaifera langsdorfii (Copaiba) are natural compounds used to prevent and treat headache and migraine and in inflammatory diseases involving respiratory airways, genital-urinary apparatus and skin, respectively, but their effects at the cellular level are poorly understood. Methods: Mouse BV-2 microglia and human THP-1 monocyte cell lines were used. The nuclear translocation of nuclear factor (NF)-kB was evaluated by Western blotting analysis. The secretion of inflammatory cytokines (interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNFα)) was evaluated by immunometric assays (ELISA). Results: Treatment of BV-2 cells with 1 μM PTN and of THP-1 cells with 10 μM Copaiba oleoresin (OR), containing diterpene acids, diterpenes and sesquiterpenes, strongly reduced the NF-kB translocation to the cell nucleus induced by 1 μg/mL lipopolysaccaride (LPS). In BV-2 cells, PTN reduced IL-6 secretion in a dosedependent manner (-29% at 200 nM, P < 0.001; -45% at 1 μM, P < 0.001; -98% at 5 μM, P < 0.001; ANOVA). Moreover, at 5 μm (highest concentration tested) PTN also reduced TNF-α secretion (-54%, P < 0.001). Preincubation of LPS-stimulated THP-1 monocytes with OR (dose-range: 0.1-10 mM), reduced the release of all tested cytokines (IL-1β, IL-6, TNF-α). Conclusions: The results obtained provide strong evidence that both cell-based models are useful to validate the anti-inflammatory properties of PTN and OR at the cellular level and suggest that they are related to inhibition of cytokine secretion and NF-κB nuclear translocation.