Metabolite profiling of whole murine embryos reveals metabolic perturbations associated with maternal valproate‐induced neural tube closure defects

Abstract

Background Valproic Acid (VPA) is prescribed therapeutically for multiple conditions, including epilepsy. When taken during pregnancy, VPA is teratogenic, increasing the risk of several birth and developmental defects including neural tube defects (NTDs). The mechanism by which VPA causes NTDs remains controversial and how VPA interacts with folic acid, a vitamin commonly recommended for the prevention of NTDs, remains uncertain. We sought to address both questions by applying untargeted metabolite profiling analysis to neural tube closure stage mouse embryos. Methods Pregnant SWV dams on either a 2ppm or 10ppm folic acid (FA) supplemented diet were injected with a single dose of VPA on gestational day E8.5. On day E9.5, the mouse embryos were collected and evaluated for neural tube closure status. LC/MS metabolomics analysis was performed to compare metabolite profiles of NTD-affected VPA-exposed whole mouse embryos to profiles from embryos that underwent normal neural tube closure from control dams. Results NTDs were observed in all embryos from VPA-treated dams and penetrance was not diminished by dietary folic acid supplementation. The most profound metabolic perturbations were found in the 10ppm FA VPA-exposed mouse embryos, compared to the other three treatment groups. Affected metabolites included amino acids, nucleobases and related phosphorylated nucleotides, lipids, and carnitines. Conclusions Maternal VPA treatment markedly perturbed purine and pyrimidine metabolism in E9.5 embryos. In combination with a high folic acid diet, VPA treatment resulted in gross metabolic changes, likely caused by a multiplicity of mechanisms, including an apparent disruption of mitochondrial beta-oxidation.

Valproic acid disrupts the biomechanics of late spinal neural tube closure in mouse embryos

“…Numerous mechanisms have been proposed by which VPA may disrupt NT closure. These include epigenetic dysregulation ( Tung and Winn, 2010 ), inhibition of folate metabolism ( Fathe et al, 2014 , Roy et al, 2008 , Semmler et al, 2017 ), suppression of nitric oxide signalling ( Tiboni et al, 2013 , Tiboni and Ponzano, 2015 ) and increased reactive oxygen species production ( Akimova et al, 2017 , Tung and Winn, 2011 ). In addition, VPA's anti-acetylation effects may disrupt post-translational modifications of other effector proteins including those involved in actin regulation.…”

Untargeted Metabolite Profiling of Cerebrospinal Fluid Uncovers Biomarkers for Severity of Late Infantile Neuronal Ceroid Lipofuscinosis (CLN2, Batten Disease)

“…Welch’s t-tests, assuming unequal variances (p < 0.05), were used for statistical testing of between-group comparisons. Graphical analysis of results and Welch’s t-tests were performed using GraphPad Prism 19 , 21 – 24 . CLN2 disease classification was performed using the proprietary open-source software Metaboanalyst 4.0 25 .…”

Based serum metabolomics analysis reveals simultaneous interconnecting changes during chicken embryonic development

“…It is now established that metabolites can be predetermined by adverse conditions before birth during early development and which play an important role in prevention of disease at adult. Several studies had reported the metabolites changes in fetuses and child (Tomiyasu et al, 2013) or rat embryos (Akimova et al, 2017). Sato, Tomonaga, Denbow, and Furuse (2009) reported the changes of amino acids during embryonic development in broiler chickens.…”