Alkamides from Tropaeolum tuberosum inhibit inflammatory response induced by TNF–α and NF–κB

Abstract

Ethno–pharmacological relevanceTropaeolum tuberosum, commonly known as “Mashua”, is one of the plants most frequently used by Andean (Peruvian–Bolivian) people as food and medicine. It is used as a remedy against a wide range of diseases, especially those related with inflammation. ObjectivesThis study aims to identify compounds active against inflammatory related conditions. Materials and methodsA bioassay–guided isolation of anti–inflammatory compounds from black and purple tubers of T. tuberosum was performed measuring TNF–α and NF–κB production in THP–1 monocytic cells. ResultsThe bioassay–guided isolation led to one active compound from purple T. tuberosum, N–oleoyldopamine (1), and another active compound from black T. tuberosum, N–(2–Hydroxyethyl)–7Z,10Z,13Z,16Z–docosatetraenamide (2). Both compounds displayed anti–TNF–α activity with IC50 values of 3.12 ± 0.19 μM and 1.56 ± 0.15 μM, respectively. Also, both compounds suppressed NF–κB with IC50 of 3.54 ± 0.02 μM and 1.77 ± 0.07 μM, respectively. ConclusionsWe identified bioactive compounds from purple and black Tropaeolum tuberosum responsible for their anti–inflammatory activity: N–oleoyldopamine (1) and N–(2–Hydroxyethyl)–7Z,10Z,13Z,16Z–docosatetraenamide (2). This is the first report which isolates these compounds from T. tuberosum and describes their anti–inflammatory activities.