camalexin

Description

Camalexin is an alkaloid released by plants of the Brassicaceae family in response to pathogen infection. In addition to antimicrobial properties and a role in plant defense, camalexin exhibits antiproliferative activity in vitro against various cancer cell lines. Camalexin is active against HeLa, Jurkat, MDA-MB-231, and CEM cancer cell lines (IC₅₀s = 50.0, 46.2, 77.7, and 67.6 μM, respectively), but it is also toxic to primary human umbilical vein endothelial cells (HUVEC; (IC₅₀ = 74.0 μM). Camalexin induces apoptosis in Jurkat cells by increasing reactive oxygen species (ROS) levels and activating caspase-8 and caspase-9. In human prostate cancer cell lines, camalexin (25 μM) is more active against aggressive lines and increases ROS levels and apoptosis via cathepsin D relocation from lysosomes to the cytosol.

Uses

Camalexin has been used in quantification and tolerance assays in Arabidopsis thaliana leaves.

Definition

ChEBI: An indole phytoalexin that is indole substituted at position 3 by a 1,3-thiazol-2-yl group.

Synthesis Reference(s)

Tetrahedron, 51, p. 773, 1995 DOI: 10.1016/0040-4020(94)00987-6

Biochem/physiol Actions

Camalexin is a phytoalexin isolated from cruciferous plants that exhibits antibacterial, antifungal, antiproliferative and cancer chemopreventive activities. Apparently, camalexin increases the ROS levels and is more effective in aggressive prostate cancer cells that express high ROS levels. In Arabidopsis thaliana, camalexin and salicylic acid confer resistance to Phytophthora capsici.