Effects of FGFR2b-ligand signaling on pancreatic branching morphogenesis and postnatal islet function

J Mol Histol. 2024 Dec 18;56(1):45. doi: 10.1007/s10735-024-10328-9.

Abstract

Pancreatic development is a complex process vital for maintaining metabolic balance, requiring intricate interactions among different cell types and signaling pathways. Fibroblast growth factor receptors 2b (FGFR2b)-ligands signaling from adjacent mesenchymal cells is crucial in initiating pancreatic development and differentiating exocrine and endocrine cells through a paracrine mechanism. However, the precise critical time window that affects pancreatic development remains unclear. To explore the roles of FGFR2b-ligands and identify the narrow window of time during which FGFR2b-ligand signaling affects pancreatic development, we used an inducible mouse model to control the expression of soluble dominant-negative FGFR2b (sFGFR2b) at various stages of pancreatic development. Our findings revealed a significant effect of FGFR2b-ligand signaling on epithelial morphology, lumen formation, and pancreatic branching during primary and secondary transition stages. Additionally, sFGFR2b expression reduced the number of Pdx1+ progenitor cells and altered the pancreatic islet structure. Furthermore, we examined the effect of mutation in FGF10, an FGFR2b ligand, on embryonic pancreatic β-cell function. FGF10 null mutant embryos exhibited reduced pancreatic size and a decrease number of islet-like structure. Although neonatal mice with haploinsufficiency for FGF10 exhibited abnormal glucose tolerance test results, indicating a potential diabetes predisposition, these abnormalities normalized with age, aligning with observations in wild type mice. Our study underscores the critical role of FGFR2b-ligand signaling in pancreatic development and postnatal islet function, offering insights into potential therapeutic targets for pancreatic disorders.

Keywords: Branching morphogenesis; Development; Glucose homeostasis; Pancreas; Progenitor.

MeSH terms

  • Animals
  • Animals, Newborn
  • Fibroblast Growth Factor 10* / genetics
  • Fibroblast Growth Factor 10* / metabolism
  • Insulin-Secreting Cells / metabolism
  • Islets of Langerhans* / growth & development
  • Islets of Langerhans* / metabolism
  • Ligands
  • Mice
  • Morphogenesis* / genetics
  • Pancreas / embryology
  • Pancreas / growth & development
  • Pancreas / metabolism
  • Receptor, Fibroblast Growth Factor, Type 2* / genetics
  • Receptor, Fibroblast Growth Factor, Type 2* / metabolism
  • Signal Transduction*

Substances

  • Receptor, Fibroblast Growth Factor, Type 2
  • Fibroblast Growth Factor 10
  • Ligands
  • Fgf10 protein, mouse