Induction of angiogenesis using VEGF releasing genipin-crosslinked electrospun gelatin mats

Abstract

Rapid and controlled vascularization of engineered tissues remains one of the key limitations in tissue engineering applications. This study investigates the possible use of natural extracellular matrix-like scaffolds made of gelatin loaded with human vascular endothelial growth factor (VEGF), as a bioresorbable platform for long-term release and consequent angiogenic boosting. For this aim, gelatin was firstly electrospun and then cross-linked at two different concentrations (0.1% and 0.5% w/v) by using genipin, a low toxic agent, in order to fabricate a suitable substrate to be loaded with VEGF. Collected fibers were homogeneous and free of beads, the fibrous structure was retained after cross-linking. Mechanical properties were deeply affected by the chemical treatment showing a different behavior, depending on the testing conditions (i.e., dry or wet state). VEGF release was assessed by means of ELISA assay: a cumulative release of about 90% (0.1% w/v) and 60% (0.5% w/v) at 28 days was measured. Both VEGF loaded mats induced cell viability, endothelial differentiation and showed chemoattractive properties when tested on human mesenchymal stromal cells (hMSCs). In vitro and in vivo angiogenic assays demonstrated that the VEGF loaded mats induced an angiogenic potential in stimulating new vessel formation similar, if not superior, to fresh VEGF. VEGF retains bioactive and pro-angiogenic potential for up to 14 days. The results demonstrated that genipin cross-linked electrospun gelatin mats loaded with VEGF could be part of a useful strategy to stimulate and induce angiogenesis in tissue engineered applications.

Genipin, a Cross-linking Agent, Promotes Odontogenic Differentiation of Human Dental Pulp Cells

“…Thus, DSPP, DMP-1, and ON were selected as specific markers of differentiation to detect the odontogenic potential of hDPCs in the present investigation. Several recent studies showed that genipin-cross-linked scaffolds induced cell differentiation of various cell types (27,28,32). Similarly, our results indicate that genipin per se can be used for odontogenic differentiation of hDPCs.…”

“…Recently, genipin and genipin-containing scaffolds have been investigated for their effects on the differentiation of cells (27,28). However, there was no previous information regarding the odontogenic effect of genipin in pulp cells for dentin-pulp complex engineering.…”

Hydrophilic PCU scaffolds prepared by grafting PEGMA and immobilizing gelatin to enhance cell adhesion and proliferation

“…To overcome this obstacle, chemical immobilization of gelatin is an effective method [35], especially glutaraldehyde which is usually used to crosslink or immobilize gelatin onto the surface of microfibers or films [36][37][38]. The immobilization amount of gelatin on the surface of fibrous scaffold usually depends on the reactive groups.…”

In VitroandIn VivoStudies of BMP-2-Loaded PCL–Gelatin–BCP Electrospun Scaffolds

“…3 Fibrous scaffolds fabricated by electrospinning have been used recently for biomedical applications because they can easily create a three-dimensional porous structure resembling the morphology of natural ECM. [4][5][6] The microstructure of electrospun scaffolds such as fiber diameter and porosity can be controlled by adjusting solution properties and operating parameters. Due to the large surface area to volume ratio of electrospun scaffolds, cell adhesion, migration, and proliferation improve.…”