Angiogenesis induction by bioactive glasses and glass-ceramics

Bioactive glasses (BGs) have an outstanding place in tissue engineering and regenerative medicine strategies. These synthetic materials were historically used for the treatment of bone and dental tissues; recent studies have proved their effectiveness in managing soft tissue injuries as well. BGs exhibit several biological properties in favor of tissue healing, including the ability to attach to tissues and promoting cell growth, proliferation, and differentiation. The release of therapeutic ions from BG structure into the surrounding environment is commonly regarded as the main mechanism associated with their biological properties. The ability to induce new blood vessel formation (i.e., angiogenesis) is among the most interesting characteristics of BGs, which may be beneficial for accelerating tissue wound healing. This capacity can be easily improved by adding specific concentrations of angiogenesis-inducing elements (e.g., copper and cobalt) to the basic formulation of BGs. All categories of BGs, including silicate-, phosphate-, and borate-based glasses, were evaluated and successfully doped with proangiogenic elements. In addition, BGs are known as suitable platforms for loading and delivery of a wide range of proangiogenic bioactive molecules like growth factors, cytokines, and chemokines. Utilizing BGs in three-dimensional (3D) scaffolds may be considered for the next generation of proangiogenic bone tissue substitutes.