Single-cell transcriptomic analyses of pancreatic islets reveals islet cell-type-specific adaptations to pregnancy and the postpartum

Pancreatic β-cell mass expands during pregnancy and regresses in the postpartum period in conjunction with dynamic metabolic demands on maternal glucose homeostasis. To understand transcriptional changes driving these adaptations in β-cells and other islet cell types, we performed single-cell RNA sequencing on islets from virgin, late gestation, and early postpartum mice. We identified transcriptional signatures unique to gestation and the postpartum in β-cells, including induction of the AP-1 transcription factor subunits and other genes involved in the immediate-early response (IEGs). Additionally, we found pregnancy and postpartum-induced changes differed within each endocrine cell type, and in endothelial cells and macrophages within islets. Together, our data reveal novel insights into cell-type specific transcriptional changes responsible for adaptations by islet cells to pregnancy and their resolution postpartum. Comparing pregnant and postpartum islets to those of non-pregnant females