Identification of environmental chemicals that activate p53 signaling after in vitro metabolic activation

• DOI: 10.1007/s00204-022-03291-5
• Publication Date: 2022-04-18T11:12:49Z
• Authors: Masato Ooka; Jinghua Zhao; Pranav Shah; Jameson Travers; Carleen Klumpp-Th...; Xin Xu; Ruili Huang; Stephen Ferguson; Kristine L. Witt; Stephanie L. Smit...; Anton Simeonov; Menghang Xia
• Keywords: Biotransformation; Xenobiotic; In vitro toxicology; Metabolic pathway; High-Throughput Screening

Currently, approximately 80,000 chemicals are used in commerce. Most have little-to-no toxicity information. The U.S. Toxicology the 21st Century (Tox21) program has conducted a battery of vitro assays using quantitative high-throughput screening (qHTS) platform to gain information on environmental chemicals. Due technical challenges, standard methods for providing xenobiotic metabolism could not be applied qHTS assays. To address this limitation, we screened Tox21 10,000-compound (10K) library, with concentrations ranging from 2.8 nM 92 µM, p53 beta-lactamase reporter gene assay (p53-bla) alone or rat liver microsomes (RLM) human (HLM) supplemented NADPH, identify compounds that induce signaling after biotransformation. Two hundred and seventy-eight were identified as active under any these three conditions. Of 278 compounds, 73 gave more potent responses p53-bla RLM, 2 HLM compared they generated without microsomes. confirm role differential responses, re-tested 75 absence NADPH heat-attenuated Forty-four treated but none HLM, became less conditions, confirming RLM metabolic activation. Further evidence biotransformation was obtained by measuring half-life parent presence Together, data support use identifying requiring biological responses.