Degradable natural polymer hydrogels for articular cartilage tissue engineering

Abstract

Articular cartilage has poor ability to heal once damaged. Tissue engineering with scaffolds of polymer hydrogels is promising for cartilage regeneration and repair. Polymer hydrogels composed of highly hydrated crosslinked networks mimic the collagen networks of the cartilage extracellular matrix and thus are employed as inserts at cartilage defects not only to temporarily relieve the pain but also to support chondrocyte proliferation and neocartilage regeneration. The biocompatibility, biofunctionality, mechanical properties, and degradation of the polymer hydrogels are the most important parameters for hydrogel-based cartilage tissue engineering. Degradable biopolymers with natural origin have been widely used as biomaterials for tissue engineering because of their outstanding biocompatibility, low immunological response, low cytotoxicity, and excellent capability to promote cell adhesion, proliferation, and regeneration of new tissues. This review covers several important natural proteins (collagen, gelatin, fibroin, and fibrin) and polysaccharides (chitosan, hyaluronan, alginate and agarose) widely used as hydrogels for articular cartilage tissue engineering. The mechanical properties, structures, modification, and structure-performance relationship of these hydrogels are discussed since the chemical structures and physical properties dictate the in vivo performance and applications of polymer hydrogels for articular cartilage regeneration and repair. REFERENCES1 Kuettner KE, Biochemistry of articular-cartilage in health and disease. Clinical Biochem 25:155-163 (1992). 2 Buckwalter JA and Mankin HJ, Articular cartilage 1. Tissue design and chondrocyte-matrix interactions.

Application of cell and biomaterial-based tissue engineering methods in the treatment of cartilage, menisci and ligament injuries

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A novel nano-composite scaffold for cartilage tissue engineering

“…[4]. TE with three basic elements include cells, biodegradable scaffolds, and growth factors strives to go back and reclaim the performance of the damaged tissues and organs [5,6]. The scaffold's have pivotal role in tissues regeneration, provide simulated environment similar to the extra cellular matrix (ECM) for cells migration, adhesion, and proliferation.…”

Synthesis and Characterization of Crosslinked Hydrogel of Konkoli (<i>Maesopsis eminii</i>) Grafted Polymethylacrylamide for a Preliminary Study as an Insulin Delivery System

“…The volume phase transitions as a response to different stimuli such as; pH, temperature, ionic strength and electro stimulus, makes these materials interesting objects of scientific observations and useful materials for use in advanced technologies [7] [8] [9] [10].…”

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