Revealing HOCl burst from endoplasmic reticulum in cisplatin-treated cells via a ratiometric fluorescent probe

The reactive oxygen species (ROS) are tightly associated with endoplasmic reticulum (ER) stress. Thus, the deep and visual insight of aberrant ROS fluctuations in the ER can help us better investigate the ER stress-associated pathology. In this work, a fluorescent probe ERC for HOCl detection in the ER based on phenothiazine-derived coumarin platform was developed. In the presence of HOCl, ERC exhibited an emission change from 609 nm to 503 nm within seconds. It also showed high sensitivity (0.44 mu mol/L) and superb photostability. Significantly, ERC displayed low cytotoxicity, good cell membrane permeability, and appreciable ER-targetability. Ultimately, the probe was successfully utilized to image exogenous and endogenous HOCl in living cells and reveal the HOCl burst in cisplatin-treated cancer cells. (C) 2021 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

The study found a close association between ROS and ER stress, and developed a fluorescent probe ERC for detecting HOCl in the ER with high sensitivity and photostability, showing low cytotoxicity and good cell membrane permeability, successfully used for imaging study.