4-tert-Octylphenol Exposure Disrupts Brain Development and Subsequent Motor, Cognition, Social, and Behavioral Functions

Figure 1

Effect of OP on the growth and proliferation of neuron cell in in vitro. (a) Confocal microscope images of cultured mouse primary cortical neuron at DIV 4 stained with antibodies against MAP2 (red) and Tau1 (green). Scale bar: 100 μm. (b–d) Quantification of relative number and length of dendrite. (b) Number of primary dendrites; (c) number of secondary dendrites; (d) average dendrite length. Both the OP 10^-8 M and OP 10^-6 M groups showed higher in the number of primary dendrites and secondary dendrites compared to vehicle group. The OP-treated groups displayed a markedly decreased length of primary dendrites compared to the vehicle group. (e–g) Quantification of relative number and length of axon. (e) Number of primary axons; (f) number of secondary axons; (g) average axon length. Both the OP 10^-8 M and the OP 10^-6 M groups showed no significant difference in the number of primary axon and secondary axon. The length of axon of primary axons was slightly decreased in the OP-treated groups compared to the vehicle group. cell culture replicates using 5 mice for each condition (cell counts: 250 cells for each group). (h) Primary cortical neuronal cells were treated OP at DIV 1 and then incubated with 10 μM BrdU for 2 h after 12 h adding OP, fixed and immunofluorescence with BrdU antibodies (red). Scale bar: 40 μm. (i) Quantification of (h). The OP-treated groups exhibited lower in the percentage of cleaved BrdU⁺ cells compared to the vehicle group. The percentage of BrdU⁺ cells in the OP 10^-6 M group was decreased compared to that in the OP 10^-8 M group. (j) Cell death was assessed by staining with a cleaved caspase-3 antibody (green) after 12 h adding OP. Scale bar: 100 μm. (k) Quantification of (j). The percentage of cleaved caspase-3⁺ cells was markedly higher in the OP-treated groups compared to the vehicle group. cell culture replicates using 5 mice for each condition (cell counts: 1,000 cells for each group). Data represent . Statistical significance was determined by one-way ANOVA with Bonferroni correction. vehicle vs. OP, vehicle vs. OP, vehicle vs. OP. ^# OP 10^-8 M vs. OP 10^-6 M. NS: no significance.

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