The role of growth factor in the repair of articular cartilage

Background: Natural degeneration or trauma of articular cartilage all can lead to its structural and functional damage. Because of its lack of blood supply and innervation, it has low metabolic activity and difficulty in self-repair after injury. Growth factors provide a new direction for the repair of articular cartilage damage and play an important role. This article will systematically summarize the research progress of traditional growth factors, mainly introduce the newly found growth factors and other synthetic compounds and inorganic particles that can induce stem cells to differentiate into cartilage.Methods: English literatures published in PubMed and SCI databases from August 2000 to August 2019 were searched, Review the relevant literature, The two authors evaluated and screened the quality of the literatures respectively, and senior authors further evaluated them to resolve the disagreement on the inclusion of literatures.Results: Growth factors can significantly promote stem cell proliferation and differentiation. A variety of growth factors can exert synergistically to promote the differentiation of stem cells into cartilage, so as to promote the regeneration of cartilage tissue and repair the damage of articular cartilage. Traditional growth factors that promote articular cartilage repair are bone morphogenetic proteins, cartilage derived morphogenetic protein, transcription growth factor β, fibroblast growth factors and insulin⁃like growth factors. Recent studies have found that kartogenin, platelet-rich plasma, platelet-rich fibrin, force growth factor, etc. can also effectively induce stem cells to differentiate into cartilage and maintain chondrocyte phenotype, synthetic compounds such as dexamethasone and some inorganic particles also promote chondrogenic differentiation.Conclusions: The newly discovered growth factors promote the development of articular cartilage repair, but its mechanism of action is not clear. There are no in vivo experimental studies on dexamethasone and inorganic particles, and its repairing effect and safety are for further study. The synergistic or antagonistic effects between different growth factors, the optimal concentration ratio, and the differences in in vivo and in vitro roles need further study. At present, the research on growth factors mostly stays at the basic stage, and there are few clinical studies, which will be an important direction for further research.