THE ESTABLISHMENT OF A HUMAN INDUCED PLURIPOTENT STEM CELL-DERIVED <i>IN VITRO</i> MODEL TO STUDY DIABETIC PERIPHERAL NEUROPATHY

Diabetic peripheral neuropathy (DPN) is the most frequent complication of diabetes, involving progressive damage to neurons, Schwann cells, and microvasculature. It results in altered pain perception, either heightened sensitivity or complete sensory loss, raising the risk of injury. Due to the structural complexity of peripheral nerves, the pathogenic mechanisms of DPN remain poorly understood, limiting therapeutic development. Human induced pluripotent stem cell (hiPSC)-based models are emerging as promising tools to recreate the cellular diversity of peripheral nerves in vitro and study DPN pathogenesis. To model DPN in vitro, we first established a rat-based system using primary Schwann cells and primary dorsal root ganglion (DRG) neurons cultures. Schwann cells were then cultured under high-glucose and hypoxic conditions to mimic diabetic stress, showing altered morphology, reduced proliferation, increased oxidative stress, and decreased expression of mature Schwann cell key markers. In parallel, dissociated rat DRG neurons exposed to the same conditions showed reduced neurite complexity, with fewer branches and junctions per cell. These findings confirm the induction of key DPNlike features in our primary cell cultures model. Building on this foundation, we differentiated human induced pluripotent stem cells (hiPSCs) into Sensory Neurons and Schwann cells following previously established protocols. We successfully obtained both iNOCs (induced-nociceptors) and iSCs (induced-Schwann cells) and cultured them under hyperglycemic conditions on the basis of preliminary data obtained on primary cell cultures. These foundational steps are critical for our ultimate goal of integrating both cell types into a multicellular system, fully human-based in vitro model of DPN. Moreover, by validating cellular responses to diabetic stress in both rat and human-derived components, we are laying the groundwork for a translational platform that will enable deeper mechanistic insights into the pathophysiology of DPN and support future personalized and therapeutic development. This work has been conducted under the National Plan for Complementary Investments to the NRRP, project “D34H– Digital Driven Diagnostics, prognostics and therapeutics for sustainable Health care” (project code: PNC0000001), Spoke 4 funded by the Italian Ministry of University.