Enhanced osteogenesis of human mesenchymal stem cells by self-assembled peptide hydrogel functionalized with glutamic acid templated peptides

Enhanced Osteogenic Differentiation via Collagen and BMP-2 Mimetic Peptide Conjugation to β-TCP Scaffolds Using a Cold Atmospheric Plasma-Assisted Strategy

Bone defects arising from trauma, disease, or surgical intervention represent significant challenges. Developing effective bone tissue engineering strategies to address these issues and promote repair is crucial. β-Tricalcium phosphate (β-TCP) has emerged as a promising synthetic graft due to its porous, degradable structure and excellent biocompatibility. However, the lack of biological cues in β-TCP limits its functionality, requiring different surface modification strategies. Bone morphogenetic protein-2 mimetic peptide (BMP; NSVNSKIPKACCVPTELSAI) and collagen mimetic peptide (CMP; GTPGPQGIAGQRGVV) have a known significant therapeutic potential due to their ability to enhance cell attachment and osteogenic differentiation. Herein, a peptide functionalization strategy for β-TCP scaffolds was introduced. Briefly, β-TCP was treated with cold atmospheric plasma (CAP) to create functional hydroxyl groups on the surface of the β-TCP. Subsequently, peptides were conjugated by using a three-step method: (1) silanization with APTES, (2) EDC activation, and (3) peptide conjugation. The successful surface modification with CAP and peptide conjugation was confirmed via XRD, FTIR, and Raman analysis. Furthermore, the effects of BMP and CMP peptides on osteogenic differentiation after CAP treatment were investigated in human mesenchymal stem cells (hMSCs). Both β-TCP/BMP and β-TCP/CMP scaffolds demonstrated excellent biocompatibility with hMSCs, enhancing cell proliferation and promoting osteogenic differentiation. Remarkably, β-TCP/CMP showed better results in terms of proliferation and differentiation compared with β-TCP/BMP. These findings highlight the clinical potential of peptide-functionalized β-TCP scaffolds for bone tissue engineering while also providing a promising methodology for β-TCP functionalization.

Self-assembled peptide-based nanofibers for cardiovascular tissue regeneration

Cardiovascular diseases are the leading cause of death worldwide, claiming millions of lives every year. Cardiac tissue engineering has emerged as a versatile option for repairing cardiac tissue and helping its regeneration. The use of nanomaterials, particularly nanofiber-based scaffolds combined with biomolecular cues like peptides, has significantly improved the compatibility and efficacy of the scaffolds for cardiac tissue regeneration. By utilising the self-assembly properties of peptides to create nanofiber scaffolds, we can achieve stability that closely mimics the natural components of cardiac tissue, making them perfect for cardiac tissue regeneration. In this review, we highlighted the dynamic process of self-assembly into nanofibers and the use of various self-assembled nanofibers for cardiovascular tissue regeneration, focusing on their roles in antithrombotic, angiogenic, differentiation, proliferation, and anti-atherosclerotic interventions.

Engineered hydrogels for peripheral nerve repair

Peripheral nerve injury (PNI) is a complex disease that often appears in young adults. It is characterized by a high incidence, limited treatment options, and poor clinical outcomes. This disease not only causes dysfunction and psychological disorders in patients but also brings a heavy burden to the society. Currently, autologous nerve grafting is the gold standard in clinical treatment, but complications, such as the limited source of donor tissue and scar tissue formation, often further limit the therapeutic effect. Recently, a growing number of studies have used tissue-engineered materials to create a natural microenvironment similar to the nervous system and thus promote the regeneration of neural tissue and the recovery of impaired neural function with promising results. Hydrogels are often used as materials for the culture and differentiation of neurogenic cells due to their unique physical and chemical properties. Hydrogels can provide three-dimensional hydration networks that can be integrated into a variety of sizes and shapes to suit the morphology of neural tissues. In this review, we discuss the recent advances of engineered hydrogels for peripheral nerve repair and analyze the role of several different therapeutic strategies of hydrogels in PNI through the application characteristics of hydrogels in nerve tissue engineering (NTE). Furthermore, the prospects and challenges of the application of hydrogels in the treatment of PNI are also discussed.

Supramolecular Peptide Nanofiber Hydrogels for Bone Tissue Engineering: From Multihierarchical Fabrications to Comprehensive Applications

Bone tissue engineering is becoming an ideal strategy to replace autologous bone grafts for surgical bone repair, but the multihierarchical complexity of natural bone is still difficult to emulate due to the lack of suitable biomaterials. Supramolecular peptide nanofiber hydrogels (SPNHs) are emerging biomaterials because of their inherent biocompatibility, satisfied biodegradability, high purity, facile functionalization, and tunable mechanical properties. This review initially focuses on the multihierarchical fabrications by SPNHs to emulate natural bony extracellular matrix. Structurally, supramolecular peptides based on distinctive building blocks can assemble into nanofiber hydrogels, which can be used as nanomorphology-mimetic scaffolds for tissue engineering. Biochemically, bioactive motifs and bioactive factors can be covalently tethered or physically absorbed to SPNHs to endow various functions depending on physiological and pharmacological requirements. Mechanically, four strategies are summarized to optimize the biophysical microenvironment of SPNHs for bone regeneration. Furthermore, comprehensive applications about SPNHs for bone tissue engineering are reviewed. The biomaterials can be directly used in the form of injectable hydrogels or composite nanoscaffolds, or they can be used to construct engineered bone grafts by bioprinting or bioreactors. Finally, continuing challenges and outlook are discussed.

Chirality-induced bionic scaffolds in bone defects repair-a review

Due to lack of amino sugar with aging, people will suffer from various epidemic bone diseases called "undead cancer" by the World Health Organization. The key problem in bone tissue engineering that has not been completely resolved is the repair of critical large-scale bone and cartilage defects. The chirality of the extracellular matrix plays a decisive role in the physiological activity of bone cells and the occurrence of bone tissue, but the mechanism of chirality in regulating cell adhesion and growth is still in the early stage of exploration. This paper reviews the application progress of chirality-induced bionic scaffolds in bone defects repair based on "soft" and "hard" scaffolds. The aim is to summarize the effects of different chiral structures (L-shaped and D-shaped) in the process of inducing bionic scaffolds in bone defects repair. In addition, many technologies and methods as well as issues worthy of special consideration for preparing chirality-induced bionic scaffolds are also introduced. We expect that this work can provide inspiring ideas for designing new chirality-induced bionic scaffolds and promote the development of chirality in bone tissue engineering. This article is protected by copyright. All rights reserved.

Repair of Peripheral Nerve Injury Using Hydrogels Based on Self-Assembled Peptides

Peripheral nerve injury often occurs in young adults and is characterized by complex regeneration mechanisms, poor prognosis, and slow recovery, which not only creates psychological obstacles for the patients but also causes a significant burden on society, making it a fundamental problem in clinical medicine. Various steps are needed to promote regeneration of the peripheral nerve. As a bioremediation material, self-assembled peptide (SAP) hydrogels have attracted international attention. They can not only be designed with different characteristics but also be applied in the repair of peripheral nerve injury by promoting cell proliferation or drug-loaded sustained release. SAP hydrogels are widely used in tissue engineering and have become the focus of research. They have extensive application prospects and are of great potential biological value. In this paper, the application of SAP hydrogel in peripheral nerve injury repair is reviewed, and the latest progress in peptide composites and fabrication techniques are discussed.

Recent Progress in the Design and Medical Application of In Situ Self-Assembled Polypeptide Materials

Inspired by molecular self-assembly, which is ubiquitous in natural environments and biological systems, self-assembled peptides have become a research hotspot in the biomedical field due to their inherent biocompatibility and biodegradability, properties that are afforded by the amide linkages forming the peptide backbone. This review summarizes the biological advantages, principles, and design strategies of self-assembled polypeptide systems. We then focus on the latest advances in in situ self-assembly of polypeptides in medical applications, such as oncotherapy, materials science, regenerative medicine, and drug delivery, and then briefly discuss their potential challenges in clinical treatment.

Reversible crosslinked assembly of a trimeric coiled-coil peptide into a three-dimensional matrix for cell encapsulation and release

Mimicking the extracellular matrix (ECM) continues to be a goal in the field of regenerative medicine. Herein, we report a modified trimeric GCN4 coiled-coil sequence containing three ligands for metal ions specifically positioned for crosslinked assembly (TriCross). In the presence of metal ions, TriCross assembles into a three-dimensional (3D) matrix with significant cavities to accommodate cells. The matrix was found to be stable in media with serum, and mild removal of the metal leads to disassembly. By assembling TriCross with a suspension of cells in media, the matrix encapsulates cells during the assembly process leading to high cell viability. Further disassembly under mild conditions allows for the release of cells from the scaffold. As such, this peptide-based material displays many of the characteristics necessary for successful 3D cell culture.