Preparation of Silk Fibroin Nanofiber Scaffold and Its Application in Tendon-Bone Healing and Sports Rehabilitation

Abstract

In this work, polylactic acid/polycaprolactone/silk fibroin (PLA/PCL/SF) nanofiber scaffolds with different mass ratios were prepared by electrospinning technology. The morphology and structure of the nanofiber scaffold were characterized with the scanning electron microscope (SEM), and its porosity and adsorption were tested using the Fourier transform infrared spectrometer (FTIR). 24 New Zealand white rabbits were rolled into control group (n = 8, with autologous tendons) and experimental group (n = 16) randomly. The PLA/PCL/SF nanofiber scaffolds were adopted to wrap autologous tendons to establish extra-articular models. Tendon-bone healing was evaluated six weeks after surgery through histological and biomechanical tests, and the related gene expressions in tissue cells were detected. It turned out that mass ratio of PLA/PCL and SF components had a considerable impact on the morphology of the nanofiber scaffold. The surface of nanofiber with a mass ratio of 3:1 was distributed with dense pores. As the content of SF increased, the porosity and adsorption of the nanofiber scaffold gradually decreased. Moreover, the experimental results suggested that the addition of SF improved the hydrophilicity of PLA/PCL/SF scaffold, which was beneficial to the adhesion and proliferation of NIH/3T3 (a mouse embryonic fibroblast cell line established by the National Institutes of Health (NIH)). In addition, histological observation results showed that the width of the tendon-bone interface (TBI) of rabbits in control group was still relatively large at the 6th week after the surgery, with poor healing effect and disordered collagen arrangement. The widths of the TBI of the material group and rehabilitation group were substantially narrower relative to that in control group, and the collagen was arranged regularly. It was suggested that the healing effects between tendon and bone in material group and rehabilitation group were accelerated, and the effect in the rehabilitation group was superior to that of material group, indicating that rehabilitation exercise could organize the negative effects of training in postoperative rehabilitation training and promote the healing between tendons and bones.

Enhanced In Vivo Wound Healing Efficacy of a Novel Piperine-Containing Bioactive Hydrogel in Excision Wound Rat Model

“…The samples of the group treated with the placebo and standard marketed preparation showed signs of collagen and re-epithelization, but these findings were more pronounced in samples treated with the piperine-containing bioactive hydrogel system. Figure 4 confirms the piperine-containing hydrogel system’s substantial wound healing potential with widespread collagen fibre [ 24 ] and the formation of the thick epidermal layer and papillary dermis [ 24 , 25 , 26 ]. The significant healing of wounds with the piperine-containing hydrogel system is attributed to the augmented and controlled accessibility of piperine to the wound bed utilizing the hydrogel formulation that hastens the process of the formation of an organized, cellular structure in newly healed skin tissues.…”

“…Recent years have seen an increase in research into the wound healing potential of natural products with anti-inflammatory, antioxidant, antibacterial, and pro-collagen synthesis actions. Phytochemicals can speed up the recovery time from wounds because of their medicinal properties [ 24 , 25 ]. The wound healing potential of piperine was explored for the first time in the current investigation.…”

“…An animal model reflects its ability when it replicates normal human processes and diseases, and it is called a true success of an animal model. The therapeutic efficacy of bioactive agents in rodent models of wound healing has been difficult to study because the contraction of the wound is rapid in rodents, leading to the rapid closure of defects [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. This comparative study was designed to demonstrate the internal and epidermal healing potential of a piperine-containing hydrogel and its conventional formulation compared to no drug treatment.…”

Bioinspired Silk Fibroin-Based Composite Grafts as Bone Tunnel Fillers for Anterior Cruciate Ligament Reconstruction

“…In fact, the naturally derived SF is a source for scientific inspiration in several biomedical applications, presenting incredible biological mimicking features and healing capabilities [17]. The combination of SF with other polymers, such as PLGA, PCL or polyethylene terephthalate (PET) [18,19], in the form of fibrous/textile structures [20,21], has successfully been proposed for the fabrication of ACLGs. In fact, an ongoing clinical trial (NCT00490594) is validating the SeriACL ® device (AbbVie, Chicago, IL, USA) made of knitted silk to replace ACL and stabilize the knee joint after surgery (www.clinicaltrials.gov, date of access: 14 February 2022), with promising outcomes.…”