Research

Publications
Title: Isothiazolinone Disrupts Reproductive Endocrinology by Targeting the G-Protein-Coupled Receptor Signaling
First author: Tang, Lizhu; Liu, Mengyuan; Li, Jing; Zhou, Bingsheng; Lam, Paul K. S.; Hu, Chenyan; Chen, Lianguo
Journal: ENVIRONMENTAL SCIENCE & TECHNOLOGY
Years: 2024
Volume / issue: /
DOI: 10.1021/acs.est.3c08577
Abstract: The unintended exposure of humans and animals to isothiazolinones has led to an increasing concern regarding their health hazards. Isothiazolinones were previously found to disrupt reproductive endocrine homeostasis. However, the long-term reproductive toxicity and underlying mechanism remain unclear. In this study, life-cycle exposure of medaka to dichlorocthylisothiazolinone (DCOIT), a representative isothiazolinone, significantly stimulated the gonadotropin releasing hormone receptor (GnRHR)-mediated synthesis of follicle stimulating hormone and luteinizing hormone in the brain. Chem-Seq and proteome analyses revealed disturbances in the G-protein-coupled receptor, MAPK, and Ca2+ signaling cascades by DCOIT. The G protein alpha i subunit was identified as the binding target of DCOIT. G alpha i bound by DCOIT had an enhanced affinity for the mitochondrial calcium uniporter, consequently changing Ca2+ subcellular compartmentalization. Stimulation of Ca2+ release from the endoplasmic reticulum and blockage of Ca2+ uptake into the mitochondria resulted in a considerably higher cytoplasmic Ca2+ concentration, which then activated the phosphorylation of MEK and ERK to dysregulate hormone synthesis. Overall, by comprehensively integrating in vivo, ex vivo, in silico, and in vitro evidence, this study proposes a new mode of endocrine disrupting toxicity based on isothiazolinones, which is expected to aid the risk assessment of the chemical library and favor the mechanism-driven design of safer alternatives.