N-cadherin mimetic hydrogels drive superior regenerative and paracrine responses in 3D cultures of adipose-derived mesenchymal stem cells.

Background: Cadherin-based biomaterials play a pivotal role in influencing the fate of mesenchymal stem cells (MSC). Enhancing the adhesion of adipose tissue-derived MSCs has been shown to augment their paracrine effects while N-cadherin biomaterials have been suggested to regulate the paracrine effects of MSCs via specific growth factors although the precise mechanisms underlying this regulation remain insufficiently understood. This study aims to compare the effects of a 3D N-cadherin mimetic environment on cell viability, apoptosis, extracellular matrix regulation, and growth factor expression with those observed in traditional 2D and 3D spheroid cultures. Additionally, the study seeks to evaluate the effects of conditioned media derived from the N-cadherin mimetic environment on the viability and migration of endothelial cells.

Materials and methods: Peptide hydrogels, including HAVDI and SCRAM, were used as N-cadherin mimetics at a concentration of 1 mM, and four experimental groups were established: 2D classical culture, 3D spheroid culture, 3D HAVDI, and 3D SCRAM. Cell viability was assessed using the MTT assay, while gene expression analysis (BCL-XL, BCL-2, BAX, MMP-9, TIMP1, MMP-2, PLAU, HGF, FGF, and VEGFR2) was performed via qRT-PCR. Secretion levels of growth factors (PDGF-BB, FGF-2, and VEGF-A) were quantified using ELISA. The effects of conditioned media on the proliferation and migration of human umbilical vein endothelial cells were evaluated through MTT assays, calcein staining, and wound healing assays.

Results: In the 3D HAVDI group, where MSCs were cultured in an N-cadherin mimetic peptide environment, cell viability increased, and apoptosis decreased. Moreover, this environment upregulated genes associated with tissue remodeling and increased the expression and secretion of growth factors, compared to the classical 2D culture. Additionally, treatment with conditioned media at 1:2 and 1:5 dilutions significantly improved the viability and migration potential of endothelial cells.

Conclusion: The N-cadherin mimetic peptide hydrogel represents a more effective culturing strategy than traditional 2D for enhancing the paracrine and regenerative properties of MSCs.