PhD Thesis Defence: Mr. Ajisafe Victor Ayobami (21/09/23)
Thesis title:
Potential Applications of Snail Mucus in Cartilage Repair and Fabrication of Porous 3D Scaffolds
Faculty advisor(s):
Prof. Ashok M Raichur
When?
21st September, 2023 (Thursday), 03:00 PM (India Standard Time)
Where
KPA Auditorium, Dept of Materials Engineering.
Abstract
Articular cartilage damage is a major challenge in orthopaedics. This medical condition is exacerbated by the inability of articular cartilage to self-repair due to the non-vascularization of the tissue and many other factors. Treatment strategies such as autologous chondrocyte implantation, microfracture, osteochondral plug transplantation, pridie perforation, spongilization and debridement have been explored for cartilage repair. However, these strategies require complex surgery and have limited success in fully regenerating functional cartilage. In this aspect, tissue engineering approaches are promising alternatives to the existing approaches for cartilage tissue repair and regeneration.
Snail mucin/mucus is a complex viscoelastic substance containing 90 – 97% water by weight, a mixture of glycosaminoglycans (GAGs), proteoglycan, enzymes, metal ions, copper, and antimicrobial peptides, collagen, glycolic acid, allantoin, and elastin. Some of these bioactive molecules exhibit wound healing, anti-inflammatory, and antibacterial properties, whereas GAGs reduce cartilage deterioration and inflammation. On the other hand, agarose is a polymeric material reported for its unique thermal and mechanical properties. It is biocompatible, biodegradable, and suitable for biomedical applications, but it lacks the cell adhesion property required for tissue engineering applications.
The objectives of this study were to investigate the potential therapeutic effects of snail mucus (SMu) in cartilage repair and to e= nhance the bioactive properties of agarose hydrogels using SMu to make blend scaffolds for potential applications in cartilage regeneration.
In the first part of this presentation, I will elucidate the potential of SMu as a therapeutic repair agent in cartilage regeneration. The SMu reduced apoptosis in human chondrocyte cells (C28/I2) by 74.5% and sufficiently promoted wound healing, evidenced by the classical scratch assay. In addition, a unique phenolic compound, 6-gingerol, was identified as a small molecule in the SMu for the first time. Subsequently, blends of agarose–snail mucus (AG-SMu) scaffolds were prepared to study the synergistic effects of the blend scaffolds on human chondrocyte cells for potential application in cartilage regeneration. The SMu improved the mechanical property of AG and enhanced the attachment of C28/I2 cells on the porous blend scaffolds.
Finally, reduced graphene oxide (rGO) was used as a filler to prepare AG-rGO-SMu composite scaffolds to reduce the scaffolds’ degradation rate to match that of the native cartilage ECM. rGO maintained the structural integrity of the scaffolds with improved mechanical properties and reduced degradation rate. The attachment of C28/I2 cells on the scaffolds was also enhanced.
The results from this study show that SMu and the blend scaffolds (AGSMu and AG-rGO-SMu) can be explored for articular cartilage repair and tissue engineering applications.