In vitro evaluation of microfluidic WS6-loaded Eudragit nanoparticles for improving insulin-producing cell differentiation

Abstract

This study explores a stem-cell–based approach for diabetes treatment by enhancing the viability and functionality of insulin-producing cells (IPCs) derived from stem cells of the apical papilla (SCAP). Although SCAP can differentiate into IPCs, limited cell survival remains a challenge. To address this, the proliferation enhancer WS6 was incorporated into Eudragit RS100 nanoparticles (NPs) using microfluidics. The WS6-loaded NPs were characterized for size, charge, PDI, morphology, stability, and drug loading. An MTT assay was performed as a preliminary screening method to evaluate the cytocompatibility of blank-NPs and to optimize treatment concentration. SCAP cells were treated with free WS6 or WS6-loaded NPs, and cellular uptake of NPs was evaluated using flow cytometry and fluorescence imaging. Additionally, the viability of treated cells was determined by propidium iodide (PI) and trypan blue. Prior to differentiation, definitive endoderm formation was assessed through SOX17 and FOXA2 expressions. After differentiation into IPCs, maturation markers such as insulin, C-peptide, PDX-1, NKX2.2, and NKX6.1 were examined, and apoptosis assays measured cell viability. Functional insulin secretion was tested using an in vitro glucose-stimulated insulin secretion (GSIS) assay. Results showed that WS6-loaded NPs significantly improved SCAP viability, increased healthy cell percentages, and enhanced IPC maturation. Treated IPCs demonstrated functional insulin secretion and improved glucose regulation. Overall, WS6-loaded NPs represent a promising approach to enhance IPC proliferation and generation for diabetes therapy.