An injectable self-assembling hydrogel based on RGD peptidomimetic β-sheets as multifunctional biomaterials

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Peptide Chemistry

Background:

• Cell adhesion to extracellular matrix is crucial for tissue genesis.
• Arg-Gly-Asp (RGD) sequences enhance cell adhesion but face limitations like enzymatic degradation and lack of specificity.
• Multifunctional materials with inherent antimicrobial properties are needed for advanced tissue engineering.

Purpose of the Study:

• To design and synthesize novel modified RGD (M_R) and RGD mimic [R(K)] peptides (M_OH and M_NH2).
• To evaluate their self-assembly into nanofibers and suitability as injectable hydrogels.
• To assess their cell adhesion capabilities and antimicrobial efficacy for tissue regeneration.

Main Methods:

• In-silico screening using HEX 8.0 docking server to analyze interactions with integrin α_Vβ₃.
• Synthesis of RGD mimic peptides incorporating a Phe-Phe moiety for β-sheet self-assembly.
• Characterization using physicochemical and spectroscopic techniques, electron microscopy, and biological assays for cell adhesion and antimicrobial activity.

Main Results:

• The synthesized peptides self-assembled into nanofibers, forming thixotropic injectable hydrogels.
• Enhanced cell adhesiveness was observed compared to commercial Poly l-lysine coated surfaces.
• Significant antimicrobial activity was demonstrated against both sensitive and antibiotic-resistant pathogens, including MRSA and MDR Salmonella enteritidis.

Conclusions:

• The novel RGD mimic peptides exhibit promising multifunctional properties for tissue engineering.
• Their injectable hydrogel nature, enhanced cell adhesion, and antimicrobial activity make them suitable for drug entrapment and 3D cell culture.
• These peptides represent a significant advancement for various tissue regenerative applications.