Nanoscale borosilicate bioactive glass for regenerative therapy of full-thickness skin defects in rabbit animal model

Abstract

Bioactive glass (BG) occupies a significant position in the field of hard and soft tissue regeneration. Different processing techniques and formulas have been introduced to expand their regenerative, angiogenic, and antibacterial properties. In the present study, a new formula of bborosilicate bioactive glass nanofibers was prepared and tested for its wound-healing efficacy in a rabbit animal model. The glass formula ((1–2) mol% of B2O3 (68–69) mol% of SiO2, and (29–30) mol% of CaO) was prepared primarily by the sol-gel technique followed by the electrospinning technique. The material was characterized for its ultrastructure using scanning electron microscopy, chemical composition using FTIR, and its dynamic in vitro biodegradability using ICP-AES. Twelve rabbits were subjected to surgical induction of full-thickness skin defects using a 1 cm2 custom-made stainlessteel skin punch. The bioactive glass nanofibers were used as a grafting material in 6 experimental rabbits, while the defects in the remaining rabbits were considered as the negative control samples. All defects were assessed clinically for the decrease in wound size and clinical signs of healing and histologically for angiogenesis, collagen density, inflammatory response, cell recruitment, epithelial lining, and appendages at 1,2 and 3 weeks following the intervention. Structural analysis of the glass fibers confirmed their nano-size which ranged from 150 to 700 nm. Moreover, the chemical analysis confirmed the presence of SiO2 and B2O3 groups within the structure of the nanofibers. Additionally, dynamic biodegradation analysis confirmed the rapid degradation of the material starting from the first 24 h and rapid leaching of calcium, silicon, and boron ions confirming its bioactivity. The wound healing study of the nanofibrous scaffold confirmed its ability to accelerate wound healing and the closure rate in healthy rabbits. Histological analysis of the defects confirmed the angiogenic, regenerative and antibacterial ability of the material throughout the study period. The results unveil the powerful therapeutic properties of the formed nanofibers and open a new gate for more experimental and clinical applications.

Advances in clinical applications of bioceramics in the new regenerative medicine era

“…This composite possesses bioactivity gained from the ionic dissolution of bioactive glass on the surface of the scaffold and sufficient strength thanks to the polymer scaffold[ 44 ]. The same was observed in the soft tissue application where researchers reported the disappearance of bioactive glass from the wound surface at day one postoperatively[ 27 , 28 ]. One of the main advantages of bioceramics is the antibacterial effect at the site of application.…”

“…An example of this was a mixture of different types of bioactive glass prepared in an ointment form[ 26 ]. Another form was borosilicate bioactive glass nanofibers, which were applied in full-thickness skin defects in rabbit animal models, where the very early ion release since the first day enhanced the cascade toward cutaneous regeneration[ 27 ]. The results were in agreement with those of an earlier study conducted on dogs[ 28 ] where 13–93Borate-based bioglass promoted full-thickness wound healing.…”

Nanofibrous Polycaprolactone Membrane with Bioactive Glass and Atorvastatin for Wound Healing: Preparation and Characterization

“…The ability of bioactive glass nanoparticles to induce the growth of new tissue makes them ideal for wound healing [ 46 , 47 ]. In a previous work [ 48 ], we prepared novel SBGs by the sol–gel method, fabricated and characterized, revealing prominent potential in biomedical applications.…”