Cycloartane Triterpenoid modulates ER stress signaling pathways

Compounds modulating Unfolded protein response (UPR) and endoplasmic-reticulum stress (ERS) could be used for therapeutic purposes. We focused on the ERS and UPR as possible pathways involved in Cycloart-23E-ene-3β, 25-diol (Cycloart-E25), a natural product, cytotoxicity against MDA-MB48 and MCF-7 breast cancer cell lines. Results indicated that Cycloart-E25 noticeably increased ROS levels and induced apoptosis in both cell lines (p>0.05) which were confirmed by increased Bax/Bcl-2 ratio and decreased ΔΨm. In both cell lines Cycl-E25 potently induced protein aggregation and upregulated CHOP, PERK, ATF6, BiP, and XBP1 factors, indicating ERS-mediated apoptosis. Collectively, Cycloart-E25 could be considered as an ERS inducer with chemopreventive properties.