Abstract
Transplantation of donor islets of Langerhans is a potential therapeutic approach for patients with diabetes mellitus; however, its success is limited by islet death and dysfunction during the initial hypoxic conditions at the transplantation site. This highlights the need to support the donor islets in the days post-transplantation until the site is vascularized. It was previously demonstrated that the extracellular matrix (ECM) proteins nidogen-1 (NID1) and decorin (DCN) improve the functionality and survival of the β-cell line, EndoC-βH3, and the viability of human islets post-isolation. To advance the use of these ECM proteins toward a clinical application and elucidate the mechanisms of action in primary islets, the study assesses the effects of ECM proteins NID1 and DCN on isolated human donor islets cultured in normoxic and hypoxic conditions. NID1- and DCN-treatment restore β-cell functionality of human donor islets in a hypoxic environment through upregulation of genes involved in glycolytic pathways and reducing DNA fragmentation in hypoxic conditions comparable to normoxic control islets. The results demonstrate that the utilization of NID1 or DCN with islets of Langerhans may have the potential to overcome the hypoxia-induced cell death observed post-transplantation and improve transplant outcomes.