Preimplantation embryo ketone body exposure exerts sex-specific effects on mouse fetal and placental transcriptomes

Ketogenic diet consumption elevates circulating levels of the ketones β-hydroxybutyrate (βOHB) and acetoacetate (AcAc). In vitro ketone exposure perturbs preimplantation mouse embryo viability and female-specific fetal development post-transfer. Here we assessed whether transient exposure of preimplantation embryos to ketones impacts post-implantation fetal and placental gene expression. Blastocysts cultured in vitro with or without 2 mmol/L βOHB alone (‘βOHB’) or combined with 0.8 mmol/L AcAc (‘Keto’) underwent embryo transfer. Transcriptional profiles of sexed E14.5 placentae, liver, and brain were examined via RNA-Seq and DAVID functional analysis, revealing a sexually dimorphic transcriptomic response. βOHB and Keto exposure both downregulated genes related to oxidative phosphorylation specifically in female liver. βOHB downregulated female placental steroid biosynthetic processes, while Keto treatment upregulated genes relevant to blood vessel formation and cell migration in male placentae. Brain transcriptomes were minimally affected. X-linked genes and chromatin modifiers were identified as differentially expressed, alluding to a sex-specific regulatory mechanism. Transient preimplantation ketone exposure therefore perturbs sex-specific fetal liver and placental gene expression demonstrating a developmental programming effect that warrants future investigation of male and female offspring postnatal metabolic health. mRNA profiles of male and female D14.5 murine fetal liver, fetal brain and placental tissues cultured in vitro with 2 mM βOHB versus control, or 0.8 mM AcAc + 2 mM βOHB versus control.

生酮饮食（Ketogenic diet）可升高循环中酮体β-羟基丁酸（β-hydroxybutyrate, βOHB）与乙酰乙酸（acetoacetate, AcAc）的水平。体外暴露于酮体可干扰植入前小鼠胚胎的存活能力，并影响移植后雌性特异性胎儿发育。本研究旨在探讨植入前胚胎短暂暴露于酮体是否会影响植入后胎儿与胎盘的基因表达。本研究将体外培养的囊胚分为三组：仅添加2 mmol/L βOHB的处理组（‘βOHB组’）、同时添加0.8 mmol/L AcAc与2 mmol/L βOHB的处理组（‘Keto组’），以及未添加酮体的对照组，随后进行胚胎移植。通过RNA测序（RNA-Seq）与DAVID功能富集分析，对分性别鉴定的E14.5胎盘、肝脏及脑组织的转录谱进行检测，结果显示存在性别二态性的转录组应答。βOHB组与Keto组均可特异性下调雌性肝脏中与氧化磷酸化相关的基因。βOHB组可下调雌性胎盘中类固醇生物合成相关基因，而Keto组则上调雄性胎盘中与血管生成及细胞迁移相关的基因。脑组织的转录组受影响程度极小。研究鉴定出X连锁基因与染色质修饰因子存在差异表达，提示存在性别特异性的调控机制。综上，植入前胚胎短暂暴露于酮体可干扰性别特异性的胎儿肝脏与胎盘基因表达，体现出发育编程效应，这提示有必要进一步研究雌雄后代出生后的代谢健康状况。本数据集包含经以下处理的雌雄小鼠D14.5胎肝、胎脑及胎盘组织的mRNA转录谱：① 体外添加2 mM βOHB处理组与对照组的对比；② 体外添加0.8 mM AcAc + 2 mM βOHB处理组与对照组的对比。