Protective Effect of Mesenchymal Stem Cells on Isolated Islets Survival and Against Hypoxia Associated With the HIF-1α/PFKFB3 Pathway

Islets have a high demand for oxygen and most of them will die of hypoxia injury before and after transplantation. Hypoxic damage is one of the key factors associated with islet graft dysfunction. Mesenchymal stem cells (MSCs) have multiple functions and can enhance the therapeutic effect of islet transplantation. In this study, islets were cultured together with or without MSCs derived from umbilical cord (hUC-MSCs) under normal and hypoxic conditions. The effect of hUC-MSCs on the survival and function of isolated islets was detected by immunofluorescence and ELISA. Hypoxia-inducible factor 1 alpha (HIF-1 alpha) and PFKFB3 mRNA and protein expression in different conditions were tested by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western Blot. The islets co-cultured with hUC-MSCs have improved viability and function compared with islets cultured alone. The mRNA transcription of HIF-1 alpha in the co-cultured group increased. The protein expression of PFKFB3 increased with the increase of HIF-1 alpha. This study found that hUC-MSCs could protect islets from dysfunction caused by hypoxia, and HIF-1 alpha/PFKFB3 played an important role in hypoxic resistance, suggesting a potential strategy to improve the outcome of islet transplantation.