Research on the Modulation of Physical Properties of Biomaterials to Enhance Vascularization

Background Introduction

In the fields of tissue engineering and regenerative medicine, the formation of a vascular system and adequate blood perfusion are crucial for ensuring the supply of nutrients and oxygen within biomaterials. However, existing biomaterials often face insufficient vascularization after implantation, leading to cell apoptosis and tissue necrosis. To address this issue, researchers have begun exploring how the physical properties of biomaterials influence the vascularization process. This article reviews the physical properties of biomaterials, including pore structure, surface topography, and stiffness, and how they promote vascularization, thereby providing better research models and personalized treatment strategies for bone regeneration, wound healing, islet transplantation, and cardiac repair.

Source of the Paper

This article was co-authored by Hao Li, Dayan Li, Xue Wang, Ziyuan Zeng, Sara Pahlavan, Wei Zhang, Xi Wang, and Kai Wang, affiliated with institutions such as Peking University Third Hospital and Peking University School of Basic Medical Sciences. The paper was published on November 30, 2024, in the journal ACS Biomaterials Science & Engineering, as part of the special issue “ACS BMSE Early Career Investigators.”

Main Content

1. The Relationship Between Physical Properties of Biomaterials and Vascularization

This article delves into how the physical properties of biomaterials influence the vascularization process, focusing on three key factors: pore structure, surface topography, and stiffness.

1.1 Pore Structure

Pore structure is a critical consideration in biomaterial design, encompassing pore size, morphology, porosity, and pore interconnectivity. Research shows that pore size directly affects the formation and maturation of blood vessels. For instance, materials with pore sizes between 50-150 micrometers support the formation of mature vascular tissues, while larger pores (200-250 micrometers) promote endothelial cell migration and vascularization. However, excessively large pores may reduce the surface area available for cell attachment and growth, thereby affecting vascularization. Additionally, pore interconnectivity is crucial for the rapid formation of vascular networks and tissue integration.

1.2 Surface Topography

Surface topography, designed at the micro- or nanoscale, can mimic the structure of the natural extracellular matrix (ECM), promoting endothelial cell attachment and migration. Studies indicate that surface nanostructures of appropriate dimensions increase the opportunities for cell attachment and prevent cell apoptosis. Furthermore, surface micro/nanotopography can influence the vascularization process by modulating macrophage polarization.

1.3 Stiffness

The stiffness of a material refers to its resistance to deformation under external forces. Research shows that matrix stiffness significantly impacts cell morphology and behavior, particularly endothelial cells, which are highly sensitive to ECM stiffness. Softer substrates promote extensive vascular network formation, while stiffer substrates may inhibit endothelial cell network formation. By adjusting material stiffness, vascularization can be maximized.

2. Applications of Biomaterials in Tissue Engineering

This article also explores the application prospects of biomaterials in fields such as bone regeneration, wound healing, islet transplantation, and cardiac repair.

2.1 Bone Regeneration

Bone regeneration is a complex biological process involving inflammation, cell proliferation, and bone tissue reconstruction. Vascularization strategies are indispensable for promoting effective bone repair. Studies show that bioceramic scaffolds with specific pore structures can promote angiogenesis and bone regeneration.

2.2 Wound Healing

In wound healing, biomaterial design requires excellent biocompatibility, vascularization capability, and antibacterial activity. Research indicates that biomaterials with micro/nanotopography can promote endothelialization and angiogenesis, thereby accelerating wound healing.

2.3 Islet Transplantation

Islet transplantation is a promising method for treating insulin-dependent diabetes. However, insufficient vascularization post-transplantation affects islet survival and function. Studies show that biomaterials with appropriate pore sizes and surface roughness can promote vascular regeneration after islet transplantation.

2.4 Cardiac Repair

In cardiac repair, biomaterial design must provide structural support and promote vascular network formation. Research indicates that biomaterials with biomimetic elasticity and strength can promote myocardial repair and vascular regeneration.

Conclusion

This article reviews the impact of biomaterial physical properties on vascularization and explores their application prospects in tissue engineering. By optimizing pore structure, surface topography, and stiffness, the efficiency and quality of vascularization can be significantly improved, facilitating successful integration of implanted materials with host tissues. Future research needs to further explore the design of 3D scaffolds capable of controlling multiple physicochemical parameters to achieve functional tissue construction and clinical applications.

Value and Significance of the Paper

This article provides important theoretical support for the application of biomaterials in tissue engineering and regenerative medicine. By modulating the physical properties of biomaterials, vascularization efficiency can be significantly enhanced, offering better treatment strategies for bone regeneration, wound healing, islet transplantation, and cardiac repair. Additionally, the article proposes future research directions, providing valuable references for the development of new biomaterials.

Highlights

• Optimization of Pore Structure: By modulating pore size, morphology, and interconnectivity, vascularization efficiency is significantly improved.
• Design of Surface Topography: Micro/nanotopography mimics the natural ECM, promoting endothelial cell attachment and migration.
• Modulation of Stiffness: By adjusting material stiffness, vascularization is maximized.
• Multidisciplinary Applications: The article explores the application prospects of biomaterials in bone regeneration, wound healing, islet transplantation, and cardiac repair.

The research findings of this article provide important theoretical foundations and practical guidance for the design and application of biomaterials, holding significant scientific value and clinical application prospects.