Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, United States.
Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, United States.
Neurotoxicol Teratol. 2023 Sep-Oct;99:107286. doi: 10.1016/j.ntt.2023.107286. Epub 2023 Jul 11.
Valproic acid (VPA) is an anti-epileptic medication that increases the risk of neural tube defect (NTD) outcomes in infants exposed during gestation. Previous studies into VPA's mechanism of action have focused on alterations in gene expression and metabolism but have failed to consider how exposure changes the abundance of critical developmental proteins over time. This study evaluates the effects of VPA on protein abundance in the developmentally distinct tissues of the mouse visceral yolk sac (VYS) and embryo proper (EMB) using mouse whole embryo culture. Embryos were exposed to 600 μM VPA at 2 h intervals over 10 h during early organogenesis with the aim of identifying protein pathways relevant to VPA's mechanism of action in failed NTC. Protein abundance was measured through tandem mass tag (TMT) labeling followed by liquid chromatography and mass spectrometry. Overall, there were over 1500 proteins with altered abundance after VPA exposure in the EMB or VYS with 428 of these proteins showing previous gene expression associations with VPA exposure. Limited overlap of significant proteins between tissues supported the conclusion of independent roles for the VYS and EMB in response to VPA. Pathway analysis of proteins with increased or decreased abundance identified multiple pathways with mechanistic relevance to NTC and embryonic development including convergent extension, Wnt Signaling/planar cell polarity, cellular migration, cellular proliferation, cell death, and cytoskeletal organization processes as targets of VPA. Clustering of co-regulated proteins to identify shared patterns of protein abundance over time highlighted 4 h and 6/10 h as periods of divergent protein abundance between control and VPA-treated samples in the VYS and EMB, respectively. Overall, this study demonstrated that VPA temporally alters protein content in critical developmental pathways in the VYS and the EMB during early organogenesis in mice.
丙戊酸（VPA）是一种抗癫痫药物，会增加在妊娠期间暴露的婴儿神经管缺陷（NTD）结局的风险。以前对 VPA 作用机制的研究集中在基因表达和代谢的改变上，但没有考虑暴露如何随时间改变关键发育蛋白的丰度。本研究使用小鼠全胚胎培养，评估 VPA 在发育上不同的小鼠内脏卵黄囊（VYS）和胚胎本身（EMB）组织中的蛋白质丰度的影响。胚胎在早期器官发生期间以 2 小时的间隔暴露于 600 μM VPA 10 小时，目的是确定与 VPA 在失败的 NTC 中的作用机制相关的蛋白质途径。通过串联质量标签（TMT）标记，然后进行液相色谱和质谱法测量蛋白质丰度。总体而言，VPA 暴露后，EMB 或 VYS 中有 1500 多种蛋白质丰度发生改变，其中 428 种蛋白质以前与 VPA 暴露有关。组织之间显著蛋白质的有限重叠支持了 VYS 和 EMB 对 VPA 有独立作用的结论。增加或减少丰度的蛋白质的途径分析确定了多个与 NTC 和胚胎发育具有机制相关性的途径，包括收敛扩展、Wnt 信号/平面细胞极性、细胞迁移、细胞增殖、细胞死亡和细胞骨架组织过程，这些都是 VPA 的靶点。共调节蛋白的聚类以识别随时间变化的蛋白质丰度的共享模式，突出了 4 小时和 6/10 小时分别是 VYS 和 EMB 中对照和 VPA 处理样品之间蛋白质丰度发散的时期。总体而言，这项研究表明，VPA 在早期器官发生期间，在小鼠的 VYS 和 EMB 中的关键发育途径中，随时间改变蛋白质含量。
