Molecular modeling, expression and wound-repair activity in vivo of platelet-derived growth factor from Periplaneta americana

Platelet-derived growth factors (PDGFs) promote the repair of the wounded tissue by stimulating macrophages to produce and secrete growth factors. Active constituents extracted from Periplaneta americana were primary for treatment of wounds, pressure sores, and burns. In this study, PDGF from Periplaneta americana (PAPDGF) was identified, and the sequence analysis, physical properties, 3D structure of PAPDGF and the interfaces of PAPDGF-PDGFRβ were predicted by bioinformatics. In addition, to explore the relationship between the key amino acid residues and activity of PAPDGF, recombinant mutant of PAPDGF (rmPAPDGF, D164H) was constructed. The sequence of PAPDGF and mutant of PAPDGF (D164H) were expressed and purified by Ni-affinity chromatography. The wound-repair activity of recombinant PAPDGF (rPAPDGF) and rmPAPDGF were tested in vivo. The results showed that rPAPDGF and rmPAPDGF were successfully obtained and exhibited a single band on SDS-PAGE at 49.87 kDa. The rPAPDGF showed potent repair activity by stimulating the expression of collagen and PDGFRβ, whereas the rmPAPDGF exhibited low repair activity in vivo, which indicated that the residue D164 in PAPDGF was the key amino acid to maintain activity. Taken together, PAPDGF may be served as a promising candidate agent for the treatment of wound in the future.