Effect of sesquiterpene lactones on the expression of the activation marker CD69 and of IL-2 in T-lymphocytes in whole blood

Sesquiterpene Lactones: Promising Natural Compounds to Fight Inflammation

Inflammation is a crucial and complex process that reestablishes the physiological state after a noxious stimulus. In pathological conditions the inflammatory state may persist, leading to chronic inflammation and causing tissue damage. Sesquiterpene lactones (SLs) are composed of a large and diverse group of highly bioactive plant secondary metabolites, characterized by a 15-carbon backbone structure. In recent years, the interest in SLs has risen due to their vast array of biological activities beneficial for human health. The anti-inflammatory potential of these compounds results from their ability to target and inhibit various key pro-inflammatory molecules enrolled in diverse inflammatory pathways, and prevent or reduce the inflammatory damage on tissues. Research on the anti-inflammatory mechanisms of SLs has thrived over the last years, and numerous compounds from diverse plants have been studied, using in silico, in vitro, and in vivo assays. Besides their anti-inflammatory potential, their cytotoxicity, structure–activity relationships, and pharmacokinetics have been investigated. This review aims to gather the most relevant results and insights concerning the anti-inflammatory potential of SL-rich extracts and pure SLs, focusing on their effects in different inflammatory pathways and on different molecular players.

Anticancer activities of two sesquiterpene lactones, millerenolide and thieleanin isolated from Viguiera sylvatica and Decachaeta thieleana

The present study was carried out in order to examine the anticancer properties of two sesquiterpene lactones, millerenolide and thieleanin, isolated from Viguiera sylvatica and Decachaeta thieleana, against cell lines in vitro, and on the growth B16/BL6 melanoma tumors in C57BL/6 mice. Millerenolide and thieleanin showed a similar pattern of cytotoxicity with the greatest effect on viability being evident with A549 human lung cancer cells (IC(50) - 40 and 32 microM respectively), and with the 3T3/HER2 cell line which are 3T3 mouse fibroblasts transfected with the HER2 oncogene (IC(50) - 16 and 28 microM respectively). The parent 3T3 cells and the B16/BL6 mouse melanoma cells were less sensitive to these compounds, with thieleanin showing an IC(50) with B16/BL6 greater than the highest dose tested (203 microM). Treatment with millerenolide (8 mg/kg, i.p. on days 0, 2 and 4 post-inoculation) significantly inhibited the growth of subcutaneous B16/BL6 tumors in C57BL/6 mice, (50% inhibition at day 25, P=0.015), as well as retarding the appearance of detectable tumor (millerenolide - day 15.2+/-0.4 vs control - day 12.8+/-0.5, mean+/-SEM, P=0.011). In contrast, treatment with thieleanin (8 mg/kg every other day up to the day of kill) neither retarded the appearance of the tumor nor its growth.