Transplantation of miR-219 overexpressed human endometrial stem cells encapsulated in fibrin hydrogel in spinal cord injury.

Oligodendrocyte (OL) loss and demyelination occur after spinal cord injury (SCI). Stimulation of remyelination through transplantation of myelinating cells may be effective in improving function. For the repair strategy to be successful, the selection of a suitable cell and maintaining cell growth when cells are injected directly to the site of injury is important. In addition to selecting the type of cell, fibrin hydrogel was used as a suitable tissue engineering scaffold for this purpose. To test the relationship between myelination and functional improvement, the human endometrial stem cells (hEnSCs) were differentiated toward oligodendrocyte progenitor cells (OPCs) using overexpression of miR-219. Adult female Wistar rats were used to induce SCI by using a compression model and were randomly assigned to the following four experimental groups: SCI, Vehicle, hEnSC, and OPC. Ten days after injury, miR-219 overexpressed hEnSC-derived OPCs encapsulated in fibrin hydrogel, as an injectable scaffold, were injected to the injury site. In this study, with a focus on promoting functional recovery after SCI, the Basso-Beattie-Bresnahan test was performed to evaluate the recovery of motor function every week for 10 weeks and the histological assay was then performed. Results showed that the rate of motor function recovery was significantly higher in OPC group compared to SCI and vehicle groups but no marked differences were found between OPC and hEnSC groups, although, the rate of myelination in the OPC group was significantly higher than the other groups. These results demonstrated that remyelination was not the cause of recovery of motor function.

In vitro physical and biological characterization of biodegradable elastic polyurethane containing ferulic acid for small-caliber vascular grafts.

Demand for small diameter vascular grafts is growing. The main limitations of these grafts include induced thrombotic events, lack of in situ endothelialization, intimal hyperplasia and poor mechanical properties which impair the graft patency rate in long-term applications. Most anti-thrombotic modification methods currently in use usually conflict with the formation of an endothelial cell monolayer on the grafts. Here, we synthesized a novel biodegradable poly(ether ester urethane)urea elastomer (PEEUU) using poly(ethylene glycol) and poly(diethylene glycol adipate) as soft segments. To improve hemocompatibility, synthesized PEEUU was blended with ferulic acid (FA). Scanning electron microscopy, water contact angle measurement, and tensile testing were used to characterize the scaffolds. The PEEUU and PEEUU-FA scaffolds revealed appropriate mechanical properties, with tensile strengths and strains similar to a coronary artery. In vitro assay demonstrated that the release of FA from the scaffold is in a sustained manner. Hemocompatibility tests indicated that the PEEUU-FA sample induced lower platelet adhesion compared to the PEEUU sample. Reductions in hemolysis and fibrinogen adsorption were detected on the PEEUU-FA sample. Cell studies showed that PEEUU-FA supported the adhesion, expansion and proliferation of endothelial cells. The cells maintained an endothelial cell phenotype through the expression of the endothelial cell marker CD31. The results revealed that the new PEEUU modified with FA can be considered as a promising candidate for vascular applications with enhanced blood compatibility and vascular cell-compatibility.