Laboratory Molecular Physiology and Adaptation, CNRS UMR 7221, Department Adaptations of Life, Muséum National d'Histoire Naturelle, F-75005 Paris, France.
Endocrine Laboratory, Department of Clinical Chemistry, Amsterdam UMC, University of Amsterdam, 1105 Amsterdam, the Netherlands.
Environ Int. 2023 Feb;172:107770. doi: 10.1016/j.envint.2023.107770. Epub 2023 Jan 21.
Neural stem cells in the murine subventricular zone (SVZ) reactivate during postnatal development to generate neurons and glia throughout adulthood. We previously demonstrated that a postnatal thyroid hormone (TH) peak orchestrates this remodelling, rendering this process vulnerable to endocrine disruption. We exposed mice to 2 or 200 µg/kg bw/day of the bisphenol A-replacement and suspected TH-disruptor bisphenol F (BPF) in the drinking water, from embryonic day 15 to postnatal day 21 (P21). In parallel, one group was exposed to the TH-synthesis blocker propylthiouracil (0.15 % PTU). In contrast to PTU, BPF exposure did not affect serum TH levels at P15, P21 or P60. RNA-seq on dissected SVZs at P15 revealed dysregulated neurodevelopmental genes in all treatments, although few overlapped amongst the conditions. We then investigated the phenotype at P60 to analyse long-term consequences of transient developmental exposure. As opposed to hypothyroid conditions, and despite dysregulated oligodendrogenesis-promoting genes in the P15 SVZ exposed to the highest dose of BPF, immunostainings for myelin and OLIG2/CC1 showed no impact on global myelin content nor oligodendrocyte maturation in the P60 corpus callosum, apart from a reduced thickness. The highest dose did reduce numbers of newly generated SVZ-neuroblasts with 22 %. Related to this were behavioural alterations. P60 mice previously exposed to the highest BPF dose memorized an odour less well than control animals did, although they performed better than PTU-exposed animals. All mice could discriminate new odours, but all exposed groups showed less interest in social odours. Our data indicate that perinatal exposure to low doses of BPF disrupts postnatal murine SVZ remodelling, and lowers the adult neuron/oligodendroglia output, even after exposure had been absent for 40 days. These anomalies warrant further investigation on the potential harm of alternative bisphenol compounds for human foetal brain development.
在出生后发育过程中,小鼠侧脑室下区(SVZ)中的神经干细胞重新激活,以在整个成年期产生神经元和神经胶质细胞。我们之前的研究表明,产后甲状腺激素(TH)峰协调了这种重塑过程,使该过程易受内分泌干扰。我们让小鼠从胚胎第 15 天到出生后第 21 天(P21)在饮用水中摄入 2 或 200μg/kg bw/天的双酚 A 替代物和疑似 TH 破坏剂双酚 F(BPF)。与此同时,一组小鼠暴露于甲状腺素合成抑制剂丙基硫氧嘧啶(0.15%PTU)中。与 PTU 不同,BPF 暴露在 P15、P21 或 P60 时均未影响血清 TH 水平。在 P15 时对分离的 SVZ 进行 RNA-seq 分析显示,所有处理组的神经发育基因均失调,尽管条件之间很少重叠。然后,我们在 P60 时分析表型以分析短暂的发育暴露的长期后果。与甲状腺功能减退症相反,尽管在 P15 时 SVZ 中暴露于最高剂量的 BPF 会导致少突胶质细胞生成促进基因失调,但免疫染色显示髓磷脂和 OLIG2/CC1 并未对 P60 胼胝体中的总体髓磷脂含量或少突胶质细胞成熟产生影响,除了厚度减小。最高剂量确实减少了 22%的新产生的 SVZ-神经母细胞的数量。与之相关的是行为改变。与对照组相比,之前暴露于最高 BPF 剂量的 P60 小鼠对气味的记忆较差,尽管它们的表现优于 PTU 暴露的动物。所有的老鼠都能区分新的气味,但所有暴露组对社交气味的兴趣都较低。我们的数据表明,围产期暴露于低剂量的 BPF 会破坏产后小鼠 SVZ 的重塑,并降低成年神经元/少突胶质细胞的输出,即使在暴露已经消失 40 天后也是如此。这些异常值得进一步研究替代双酚化合物对人类胎儿大脑发育的潜在危害。