Development of a simplified human embryonic stem cell-based retinal pre-organoid model for toxicity evaluations of common pollutants

AbstractObjective To explore the retinal toxicity of pharmaceuticals and personal care products (PPCPs), flame retardants, bisphenols, phthalates, and polycyclic aromatic hydrocarbons (PAHs) on human retinal progenitor cells (RPCs) and retinal pigment epithelial (RPE) cells, which are the primary cell types at the early stages of retinal development, vital for subsequent functional cell type differentiation, and closely related to retinal diseases.Materials and methods After 23 days of differentiation, human embryonic stem cell (hESC)-based retinal pre-organoids, containing RPCs and RPE cells, were exposed to 10, 100, and 1000 nM pesticides (butachlor, terbutryn, imidacloprid, deltamethrin, pendimethalin, and carbaryl), flame retardants (PFOS, TBBPA, DBDPE, and TDCIPP), PPCPs (climbazole and BHT), and other typical pollutants (phenanthrene, DCHP, and BPA) for seven days. Then, mRNA expression changes were monitored and compared.Results (1) The selected pollutants did not show strong effects at environmental and human-relevant concentrations, although the effects of flame retardants were more potent than those of other categories of chemicals. Surprisingly, some pollutants with distinct structures showed similar adverse effects. (2) Exposure to pollutants induced different degrees of cell detachment, probably due to alterations in extracellular matrix and/or cell adhesion.Conclusions In this study, we established a retinal pre-organoid model suitable for evaluating multiple pollutants’ effects, and pointed out the potential retinal toxicity of flame retardants, among other pollutants. Nevertheless, the potential mechanisms of toxicity and the effects on cell detachment are still unclear and deserve further exploration. Additionally, this model holds promise for screening interventions aimed at mitigating the detrimental effects of these pollutants.Keywords: Environmental pollutantshuman embryonic stem cellsstem cell toxicologyretinal toxicityorganoid Authors’ contributionsYue Wang: Conceptualization; Methodology; Formal analysis; Investigation; Writing–original draft; Writing–review & editing. Nuoya Yin: Conceptualization; Funding acquisition; Supervision, Writing–review & editing. Renjun Yang: Conceptualization; Funding acquisition; Supervision. Miaomiao Zhao: Investigation. Shichang Li: Investigation. Shuxian Zhang: Investigation. Yanyi Zhao: Investigation. Francesco Faiola: Conceptualization; Funding acquisition; Supervision; Writing–review & editing.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was supported by the Ministry of Science and Technology of the People’s Republic of China [no. 2020YFA0907500]; National Natural Science Foundation of China [nos. 22150710514, 22021003, 22106174]; and Strategic Priority Research Program of the Chinese Academy of Sciences [no. XDPB200202]. Figures 1B and 2 were made using GraphPad Prism 8 (GraphPad Software Inc.).