title: Impact of proangiogenic factors on organization and biodegradation of a collagen matrix. An immunohistochemical study in rats.
abstract: OBJECTIVE
  The aim of the present study was to investigate the impact of proangiogenic factors [erythropoetin (EPO), human growth hormone (HGH), fibroblast growth factor (FGF), and platelet derived growth factor (PDGF-BB)] on the organization and biodegradation of a porcine-derived collagen matrix (CM) in rats.
  
  
  METHODS
  Collagen matrix specimens were soak-loaded either with EPO, HGH, FGF or PDGF-BB, each delivered in three concentrations (high, medium, low), and randomly allocated in unconnected subcutaneous pouches separated surgically on the back of 112 Wistar rats, which were divided into four groups (4, 7, 14 and 60 days of healing). Tissue biopsies were prepared for histological (e.g. CM thickness - TH, tissue contact - TC) and immunohistochemical (collagen type III - C3) analysis.
  
  
  RESULTS
  Collagen matrix specimens of the control group were associated with an ingrowth of C3 fibres and subsequently an increase in TH at 7 (11%), 14 (20%) and 60 (21%). Factor application in different concentrations was commonly associated with a faster organization, but also significant biodegradation of CM at 7 (PDGF-M, FGF-M, HGH-H) and 14 days (EPO-H, HGH-L). All groups investigated revealed a comparable increase in mean TC values over time.
  
  
  CONCLUSIONS
  Within the limits of the present study, it was concluded that all proangiogenic factors investigated were associated with a pronounced organization of CM by C3 fibres and a biodegradation of the matrix body. EPO may serve as an alternative to PDGF-BB.
authors.affiliation: Department of Oral Surgery, Heinrich Heine University, Düsseldorf, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Schwarz
authors.forename: Gordon
authors.initials: G
authors.lastname: John
authors.forename: Thomas
authors.initials: T
authors.lastname: Kaiser
authors.forename: Ilja
authors.initials: I
authors.lastname: Mihatovic
authors.forename: Vladimir
authors.initials: V
authors.lastname: Golubovic
authors.forename: Jürgen
authors.initials: J
authors.lastname: Becker
mesh_terms: D000818:Animals; D000077214:Becaplermin; D002470:Cell Survival; D024061:Collagen Type III / Q000378:metabolism*; D004921:Erythropoietin / Q000494:pharmacology; D005346:Fibroblast Growth Factors / Q000494:pharmacology; D019382:Human Growth Hormone / Q000494:pharmacology; D007124:Immunoenzyme Techniques; D023421:Models, Animal; D020574:Proto-Oncogene Proteins c-sis / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013552:Swine; D014945:Wound Healing / Q000187:drug effects
chemical_list: D024061:Collagen Type III; D020574:Proto-Oncogene Proteins c-sis; D004921:Erythropoietin; D019382:Human Growth Hormone; D000077214:Becaplermin; D005346:Fibroblast Growth Factors
keywords: angiogenic factors; animal study; biodegradation; collagen matrix; immunohistochemistry