Placental transcriptome reveals the placental brain axis genes and pathways of gestational diabetes mellitus (GDM) affecting offspring neurodevelopment.

This study aims to analyze the pathways and the placental brain axis genes of gestational diabetes mellitus (GDM) affecting offspring neurodevelopment. Differentially expressed genes (DEGs) were identified through transcriptome sequencing of placental tissues. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed on DEGs. A protein-protein interaction (PPI) network was constructed and annotated using the STRING online software. The expression of neurodevelopment-related genes was analyzed by qPCR. Hubgenes were analyzed using Cytoscape 3.7.1 software. The correlation between Hubgenes and placental brain axis genes was analyzed through literatures alignment. The pathways of GDM affecting offspring neural development were predicted using the KEGG database. The placental transcriptome revealed that there were 404 DEGs between GDM and Normal groups. Among these DEGs, 125 were upregulated and 279 were downregulated. GO analysis indicated that DEGs were mainly involved in intracellular calcium activated chloride channel activity, anion channel activity, G protein-coupled peptide receptors, etc. Additionally, KEGG analysis revealed that DEGs were predominantly involved in neuroactive ligand receptor interaction pathways. STRING online software analysis revealed that the DLGAP1, NXNL2, SCG2, SLC18A2, LYNX1, GRM1, DLGAP1, BIRC7 genes were associated with neurodevelopment. PCR validation of these 8 genes was consistent with transcriptome results (P<0.05). Literatures alignment showed that DLGAP1, GRM1 and SLC18A2 are placental brain axis genes that influence offspring neurodevelopment. The placental brain axis genes DLGAP1, GRM1, SLC18A2 have been found to influence GDM offspring neurodevelopment through the regulation of the Gq/PLC/PKC pathway.