Overview of natural hydrogels for regenerative medicine applications

Abstract

Hydrogels from different materials can be used in biomedical field as an innovative approach in regenerative medicine. Depending on the origin source, hydrogels can be synthetized through chemical and physical methods. Hydrogel can be characterized through several physical parameters, such as size, elastic modulus, swelling and degradation rate. Lately, research is focused on hydrogels derived from biologic materials. These hydrogels can be derived from protein polymers, such as collage, elastin, and polysaccharide polymers like glycosaminoglycans or alginate among others. Introduction of decellularized tissues into hydrogels synthesis displays several advantages compared to natural or synthetic based hydrogels. Preservation of natural molecules such as growth factors, glycans, bioactive cryptic peptides and natural proteins can promote cell growth, function, differentiation, angiogenesis, anti-angiogenesis, antimicrobial effects, and chemotactic effects. Versatility of hydrogels make possible multiple applications and combinations with several molecules on order to obtain the adequate characteristic for each scope. In this context, a lot of molecules such as cross link agents, drugs, grow factors or cells can be used. This review focuses on the recent progress of hydrogels synthesis and applications in order to classify the most recent and relevant matters in biomedical field.

Proteins and Peptides as Important Modifiers of the Polymer Scaffolds for Tissue Engineering Applications—A Review

“…During this process, some contaminations may occur. Consequently, their presence may lead to immune response by body [15,40,43]. For this reason, artificial forms of elastin, i.e., synthetic tropoelastin, α-elastin, elastin-like polypeptides (ELPs), and elastin-like recombinamers (ELRs), have been developed.…”

“…For this reason, artificial forms of elastin, i.e., synthetic tropoelastin, α-elastin, elastin-like polypeptides (ELPs), and elastin-like recombinamers (ELRs), have been developed. Thanks to their high elasticity, water-solubility, biocompatibility, and biodegradability, they currently constitute good alternatives for elastin [14,15,38,40,70].…”

“…The adhesive glycoproteins, i.e., fibronectin, laminins, and vitronectin, play a key role in supporting cell migration and adhesion to ECM. Among these proteins, fibronectin and laminins are mainly used for modification of both natural and synthetic biomaterials in order to improve their biocompatibility [3,6,7,9,12,15,18,19,[72][73][74]].…”

“…Considering these requirements, the scaffolds based on natural and synthetic polymers alone, as well as composites, exhibit the highest biomedical potential [12][13][14]. Among known biodegradable natural polymers, collagen, gelatin, chitosan, elastin, hyaluronic acid (HA), and silk fibroin are commonly used for TE purposes [15,16]. In turn, poly-ε-caprolactone (PCL), polylactic acid (PLA), poly-glycolic acid (PGA), and poly(lactic-co-glycolic acid) (PLGA) have attracted great attention in the group of biodegradable synthetic polymers [17,18].…”

The Application of Hyaluronic Acid-Based Hydrogels in Bone and Cartilage Tissue Engineering

“…(1) Maintaining the phenotype of the osteoblasts or chondrocytes (2) Rebuilding the interface of bone and cartilage and lessening the generation of fibrous cartilage (3) Mimicking the natural ECM to create an ecological microenvironment (4) Providing a sufficient vascularization or secretory matrix to sustain nutrition and metabolism (5) Displaying a suitable degradation rate and no biological hazard after degradation (6) Possessing the ability to deliver growth factors and drugs [6,15,27,[33][34][35][36] At present, the polymers used for hydrogel generation are divided into natural polymers and synthetic polymers. Natural polymers include HA, chitosan, fibrin, gelatin, alginate, gellan gum, amylopectin, self-assembling peptides, and respective derivatives.…”