UCN2: a new candidate influencing pancreatic β-cell adaptations in pregnancy.

The corticotropin-releasing hormone (CRH) family of peptides, including urocortin (UCN) 1, 2 and 3, are established hypothalamic neuroendocrine peptides, regulating the physiological and behaviour responses to stress indirectly, via the hypothalamic-pituitary-adrenal (HPA) axis. More recently, these peptides have been implicated in diverse roles in peripheral organs through direct signalling, including in placental and pancreatic islet physiology. CRH has been shown to stimulate insulin release through activation of its cognate receptors, CRH receptor 1 (CRHR1) and 2.

A role for placental kisspeptin in β cell adaptation to pregnancy.

During pregnancy the maternal pancreatic islets of Langerhans undergo adaptive changes to compensate for gestational insulin resistance. Kisspeptin has been shown to stimulate insulin release, through its receptor, GPR54. The placenta releases high levels of kisspeptin into the maternal circulation, suggesting a role in modulating the islet adaptation to pregnancy.

Placental peptides regulating islet adaptation to pregnancy: clinical potential in gestational diabetes mellitus.

Pregnancy involves a progressive increase in insulin resistance and the β-cells must adapt to compensate and prevent gestational diabetes (GDM). In this review we discuss the evidence for placental peptides, including placental lactogen, hepatocyte growth factor, adiponectin and leptin, playing a role in the islet adaptation to pregnancy. The difficulties of translating data from rodent models into human pregnancy are covered and we summarise studies investigating associations between serum placental peptides and GDM risk.

Pre-culturing islets with mesenchymal stromal cells using a direct contact configuration is beneficial for transplantation outcome in diabetic mice.

Background Aims: We recently showed that co-transplantation of mesenchymal stromal cells (MSCs) improves islet function and revascularization in vivo. Pre-transplant islet culture is associated with the loss of islet cells. MSCs may enhance islet cell survival or function by direct cell contact mechanisms and soluble mediators.