Amniotic fluid stem cells prevent β-cell injury

Background aims. The contribution of amniotic fluid stem cells (AFSC) to tissue protection and regeneration in models of acute and chronic kidney injuries and lung failure has been shown in recent years. In the present study, we used a chemically induced mouse model of type 1 diabetes to determine whether AFSC could play a role in modulating beta-cell injury and restoring beta-cell function. Methods. Streptozotocin-induced diabetic mice were given intracardial injection of AFSC; morphological and physiological parameters and gene expression profile for the insulin pathway were evaluated after cell transplantation. Results. AFSC injection resulted in protection from beta-cell damage and increased beta-cell regeneration in a subset of mice as indicated by glucose and insulin levels, increased islet mass and preservation of islet structure. Moreover, beta-cell preservation/regeneration correlated with activation of the insulin receptor/Pi3K/Akt signaling pathway and vascular endothelial growth factor-A expression involved in maintaining beta-cell mass and function. Conclusions. Our results suggest a therapeutic role for AFSC in preserving and promoting endogenous beta-cell functionality and proliferation. The protective role of AFSC is evident when stem cell transplantation is performed before severe hyperglycemia occurs, which suggests the importance of early intervention. The present study demonstrates the possible benefits of the application of a non-genetically engineered stem cell population derived from amniotic fluid for the treatment of type 1 diabetes mellitus and gives new insight on the mechanism by which the beneficial effect is achieved.