title: Recombinant human platelet-derived growth factor enhances repair of cutaneous full-thickness excision by increasing the phosphorylation of extracellular signal-regulated kinase in diabetic rat.
abstract: OBJECTIVE
  To investigate the possible signaling mechanisms by which recombinant human platelet-derived growth factor (rhPDGF) accelerated healing of cutaneous wound in diabetic rats.
  
  
  METHODS
  Four full-thickness skin wounds were incised in the back of 26 male Wistar diabetic rats. The wounded rats were divided into 3 groups (7 or 8 rats each group). One group without treatment was used as a control, and the other 2 groups were treated with rhPDGF at a dose of 7.0 microg/cm2 wound or vehicle (DMSO/0.9% NaCl, vol/vol 1:1) from 1 to 14 days. The wound healing was evaluated by the measurements of the wound volume and area. Immunofluorescent and immunohistochemical staining were used to examine the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and the expression of proliferative cell nuclear antigen (PCNA), respectively.
  
  
  RESULTS
  Granulation tissue appeared in the bed of wound after injury. The number of blood capillary buds and fibroblasts was greater in the rhPDGF-treated group than that in the other 2 groups. A lot of inflammatory cells infiltration and collagen deposition were observed in the wound. The wound-volume in the rhPDGF-treated group was smaller than that in control group (P < 0.05). The reepithelialization rate in rhPDGF-treated group was higher than that in the other 2 groups at 7 days after injury (P < 0.05). The expression of PCNA in reparative cells was higher in rhPDGF-treated group than in control group or vehicle-treated group at 3,7 days after injury (P < 0.05). The phosphorylation of ERK1/2 was stronger in rhPDGF-treated group than that in control group or vehicle group at 7 and 14 days after injury (P < 0.05).
  
  
  CONCLUSIONS
  These results suggest that rhPDGF accelerates wound healing and improves healing quality by increasing the phosphorylation of ERK1/2.
authors.affiliation: Department of Plastic Surgery, Guangzhou General Hospital of Guangzhou Military Region, Guangzhou Guangdong, 510010, P.R. China.
authors.forename: Biao
authors.initials: B
authors.lastname: Cheng
authors.forename: Hongwei
authors.initials: H
authors.lastname: Liu
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Fu
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Sheng
authors.forename: Tongzhu
authors.initials: T
authors.lastname: Sun
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D008297:Male; D010766:Phosphorylation; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000494:pharmacology; D012867:Skin / Q000293:injuries; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D010982:Platelet-Derived Growth Factor; D011994:Recombinant Proteins; D048049:Extracellular Signal-Regulated MAP Kinases