Chloride Ion Transport by PITENINs across the Phospholipid Bilayers of Vesicles and Cells

ACS Appl Bio Mater. 2020 Feb 17;3(2):935-944. doi: 10.1021/acsabm.9b00985. Epub 2020 Jan 30.

Abstract

Small-molecule-based Cl- ion carriers are gaining revived attention because of their recently discovered role toward anticancer activity. Herein, we showed that the anticancer agents, PITENINs, have an efficient transmembrane Cl- ion transport activity. Theoretical calculations, 1H NMR titration, and spectrophotometric analysis suggest that the PITENINs strongly bind with a Cl- ion. In addition to the lipophilicity, the presence of both acylthiourea and phenolic OH moieties of the compounds plays a crucial role in the transport of Cl- ions. Among the tested compounds, PIT-1 and DM-PIT-1 showed higher Cl- ion selectivity and transport efficiency. Mechanistic studies demonstrated that the potent compounds follow the H+/Cl- transport pathway. Cellular activity studies showed that the disruption of Cl- ion homeostasis by PIT-1 and DM-PIT-1 preferentially promotes apoptotic cell death.

Keywords: PITENINs; acylthiourea; apoptosis; bilayers; ion transporter.