FGFs and the downstream signaling involve in tissue regeneration

      After significant research over the last decades, tissue engineering has recognized as a potential tool to regenerate damaged and diseased tissues. As one of the critical components in tissue regeneration, fibroblast growth factors (FGFs) shown the potential effects on the repair and regeneration of tissues. Fibroblast growth factor was found in pituitary extracts by Armelin in 1973, is widely expressed in cells and tissues.

     In mammalian systems, there are 22 FGFs and four FGF receptors (FGFRs). Each receptor is activated by binding FGF, leading to the formation of FGFR homodimers and activation of downstream signaling, including the PLC pathway, the PI3K pathway, and the MAPK pathway.

     FGFs have the biological activity of inducing cell proliferation, migration, differentiation, and angiogenesis. In the effects on skin, both FGF1 and FGF2 are known to be highly released by damaged endothelial cells and macrophages at wound sites[1]. The involvement of FGF2 was shown to greatly improve wound closure in  tissue formation and epithelialization of the wounds.

     During muscle regeneration, FGF6 is a key factor because it is muscle specific and highly upregulated. FGF2 was also demonstrated to promote the recruitment of skeletal muscle satellite cells using a single myofiber culture model[2].

     On bone regeneration, FGF2 have also shown possible effects. FGF2 was found to enhance the expression of osteogenic markers and mineralization, suggesting a possible role in bone regeneration[3].
As one of the neurotrophic factors, FGFs have been shown to enhance the in vitro survival and growth of neurons as well as in vivo wound healing and neuronal functions.

     In conclusion, FGFs in the regeneration of tissues, including skin, muscle, bone, and nerve tissues, play the important roles. Therefore, FGFs and the downstream signaling may be the potential targets in the treatment of diseases associated with tissue regeneration. 

[1]. Biotechnology therapeutics, 1; 55–68.
[2].Journal of Histochemistry and Cytochemistry, 47; 23–42.
[3]. Biomaterials, 19; 1781–1789.