Cinchophen induces RPA1 related DNA damage and apoptosis to impair ENS development of zebrafish.

Nonsteroidal anti-inflammatory drugs (NSAIDs) have become contaminants widely distributed in the environment due to improper disposal and discharge. Previous study has found several components might involve in impairing enteric nervous system (ENS) development of zebrafish, including NSAIDs cinchophen. Deficient ENS development in fetal could lead to Hirschsprung disease (HSCR), a congenital neurocristopathy characterized by absence of enteric neurons in hindgut. However, the intrinsic mechanism of neurotoxicity of cinchophen is unclear. We confirmed that cinchophen could impair ENS development of zebrafish and transcriptome sequencing revealed that disfunction of Replication protein A1 (RPA1), which is involved in DNA replication and repairment, might be relevant to the neurotoxicity effects induced by cinchophen. Based on previous data of single cell RNA sequencing (scRNA-seq) of zebrafish gut cells, we observed that rpa1 mainly expressed in proliferating, differentiating ENS cells and neural crest progenitors. Interestingly, cinchophen induced apoptosis and impaired proliferation. Furthermore, cinchophen caused DNA damage and abnormal activation of ataxia telangiectasia mutated/ Rad3 related (ATM/ATR) and checkpoint kinase 2 (CHK2). Finally, molecular docking indicated cinchophen could bind and antagonize RPA1 more effectively. Our study might provide a better understanding and draw more attention to the role of environmental factors in the pathogenesis of HSCR. And the mechanism of cinchophen neurotoxicity would give theoretical guidance for clinical pharmacy.