Silk Fibroin Porous Scaffolds Loaded with a Slow-Releasing Hydrogen Sulfide Agent (GYY4137) for Applications of Tissue Engineering

Abstract

Hydrogen sulfide (H 2 S) is a physiological gasotransmitter known to possess a regulatory role in several tissues, including bone. The exogenous administration by injection of solutions of H 2 S-releasing compounds (e.g., GYY4137) has been previously investigated as a novel therapeutic approach for the treatment of bone diseases. Here, GYY4137 was embedded into fibroin sponges, previously shown to be suitable as scaffolds for bone, thanks to their biocompatibility, scalable porous structure, and biodegradability rate. Fibroin porous scaffolds were produced by solvent casting and the particulate leaching method, and GYY4137 was successively incorporated by using dimethyl sulfoxide (DMSO) as vehicle. The process used to produce GYY4137-loaded scaffolds allowed the incorporation of different controlled amounts of GYY4137 into fibroin matrices. The loading process preserved the properties of the system components in the final products, as assessed by SEM, FT-IR, NMR, and different thermal analyses techniques. Release of H 2 S from GYY4137 incorporated into the scaffolds was monitored upon incubation in saline solution at physiological pH: H 2 S-release kinetic was found to be dependent on the amount of GYY4137. To ensure biocompatibility, mouse fibroblasts and human primary bone marrow stromal cells were seeded onto scaffolds, and short-term viability assays were performed. Results showed that the GYY4137-loaded scaffold did not induce cytotoxicity in any of the cell type tested. Our findings demonstrate that embedding an H 2 S-releasing donor in silk fibroin scaffold is a suitable strategy to achieve a long-lasting release of H 2 S that preserves cell viability and allows local delivery at sites of tissue injury.

Preparation and characterization of a soluble eggshell membrane/agarose composite scaffold with possible applications in cartilage regeneration

“…Instead, in wet conditions both scaffold results to have a compressive strength at least one order of magnitude lower than the natural cartilage. However, it should be noticed that the value reported in wet conditions are like the one obtained in literature, for other biopolymer‐based scaffold proposed for cartilage applications (Gambari et al., 2019; Pulkkinen et al., 2006; Raggio et al., 2018). We performed also a mechanical test on the hydrogels just before the lyophilization to form the sponges.…”

A Design of Experiment Rational Optimization of the Degumming Process and Its Impact on the Silk Fibroin Properties

“…The combinations of properties such as high mechanical strength, easy processability, and resorbability make this material unique among the other available biopolymers because of its exceptional versatility . In particular, in tissue engineering, silk fibroin in different structural forms is widely studied as a material for bone, − cartilage, − tendon, − skin, − and cornea regeneration − and, in minor part, for nerve, muscle, spinal cord, and liver regeneration . In addition, the possibility to produce different structures and to chemically modify the regenerated protein allows the use of silk fibroin in an increasing number of frontier applications in which traditional fields like electronics and optics encounter the integration with biology (bio-electronics − and bio-optics − ).…”

A Bio-inspired Multifunctionalized Silk Fibroin

“…The single steps are described in the following. Silk fibroin solution preparation. Bombyx mori cocoons (purchased from Chul Thai SilkCo., Phetchabun, Thailand) were degummed by treating twice with Na 2 CO 3 aqueous solution (1.1 g/L) at 98 °C (1.5 h for each treatment) and rinsed with distilled water. The degummed silk fibroin was dissolved in 9.3 M LiBr solution (1 g/10 mL) at 65 °C for 4 h. The solution was dialyzed in a Slide-A-Lyzer Cassette (ThermoScientific), MWCO 3500 Da, against distilled water for 3 days. Diazonium coupling reaction.…”