The ecological risks of tire antioxidant 6PPD and its transformed metabolite 6PPD-quinone (6PPDQ) have received high attention. The present study evaluated the developmental neurotoxicity and potential mechanisms under 6PPD or 6PPDQ embryonic exposures in zebrafish. Our findings revealed that embryonic exposure to both compounds suppressed larval locomotion during dark periods, while only 6PPD significantly reduced the larval light stimulus sensitivity and phototactic response. Following recovery to juvenile stages, pretreated fish exhibited heightened anxiety and reduced sociability for both chemicals, aggression was exclusively occurred in 6PPDQ, shoaling pattern was tighter in 6PPDQ but looser in 6PPD. Both compounds elevated larval cell death and oxidative stress while inhibiting cranial development, with 6PPD increasing and 6PPDQ decreasing inter-ocular distance. Transgenic strain analyses demonstrated that 6PPD markedly activated Gfap and Olig2 expression in the eye-brain axis region, whereas 6PPDQ specifically enhanced Olig2 expression in brain region. Retinal müller cells (labeled by Gfap) and cone cell patterns were disrupted exclusively by 6PPD, as was the fan-like lens arrangement visualized via Cms1 mitochondrial labeling. Molecular analyses aligned with these observations that both compounds altered neural development genes (sox2, nrxn2a, rab33a), while 6PPD specifically dysregulated ocular development genes (cyp26a, rlbp1b, rdh5). Conversely, 6PPDQ exhibited stronger activation of xenobiotic metabolism and redox activity genes (cyp1a, gstp1, prdx1, p4ha1a) and uniquely upregulated intestinal immune (ccr9a) and potassium channel (kcnj1a.3) genes expression. In silico affinity analysis corroborated these distinctions, showing 6PPD’s preferential binding to CYP26A and 6PPDQ’s stronger interaction with CYP1A. These findings collectively suggest that 6PPD and 6PPDQ induce divergent neurotoxicity pathways of eye-brain axis disruption and gut-brain communication perturbation, respectively, which likely drive their compound-specific behavioral effects.

Gitelman Syndrome (GS) is an inherited autosome recessive disorder syndrome, which can be caused by the gene mutations of solute carrier family 12 member 3 gene (SLC12A3). In present study, the urine cells (UCs) of a 7-year-old male GS patient with the homozygote SLC12A3 gene mutation p.T60M (c.179C > T) were reprogrammed into induced pluripotent stem cells (iPSCs) named WMUi021-A through the commercial Sendai virus reprogramming kit. The pluripotent markers OCT4 and SOX2 can be expressed positively in WMUi021-A, which can be differentiated into three germ layers in vitro as well as maintain a stable karyotype (46, XY).

Antley-Bixler syndrome (ABS) is a rare inherited autosome recessive malformation syndrome, which can be caused by the gene mutations of cytochrome P450 oxidoreductase (POR). In this study, the urine cells (UCs) derived from a 5-year-old female ABS patient with the homozygote POR gene mutation p.R457H (c.1825C>G) were reprogramming into induced pluripotent stem cells (iPSCs) named WMUi018-A using a commercial Sendai virus reprogramming kit. The pluripotent markers of stem cells like OCT4 and SOX2 can be positively expressed in this iPSC line, which can be induced to differentiate into three germ layers in vitro and maintain a stable karyotype (46, XX).

Noonan Syndrome (NS) is an inherited autosome dominant disorder syndrome, which can be caused by the mutations of serine/threonine kinase rapidly accelerated fibrosarcoma 1 (RAF1) gene. Here, an induced pluripotent stem cell (iPSC) line named WMUi022-A derived from urine cells (UCs) of a 9-year-old male NS patient with the heterozygote RAF1 gene mutation p.S257L (c.770C > T) was established through the commercial Sendai virus reprogramming kit. The pluripotent markers like OCT4 and SOX2 can be expressed positively in WMUi022-A, which can be induced into three germ layers in vitro as well as maintain a normal karyotype (46, XY).