title: Improved viability of random pattern skin flaps through the use of adipose-derived stem cells.
abstract: BACKGROUND
  Flap necrosis caused by inadequate blood supply is a common postoperative complication in reconstructive surgery. Because a putative stem cell population within the adipose tissue has been found to possess angiogenic potential, the authors sought to determine whether these cells might selectively induce neovascularization and increase the viability of random pattern skin flaps.
  
  
  METHODS
  Adipose-derived stem cells were isolated from the inguinal fat pads of ICR mice and expanded ex vivo for three passages. After the elevation of cranially based random pattern skin flaps (3 cm long and 1 cm wide), 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine (DiI)-labeled adipose-derived stem cells were then injected into the pedicle base (group A) or 1.5 cm distal to the pedicle (group B). Medium containing no adipose-derived stem cells, mature adipocytes, or basic fibroblast growth factor were injected in three other control groups separately (n = 10 for each group). Millimetric measurements were taken at postoperative day 7 for evaluation of flap viability. Specimens were harvested for histologic analyses.
  
  
  RESULTS
  Adipose-derived stem cells led to a statistically significant increase in flap viability in both group A and group B compared with the control and the adipocyte groups. Histologic examination also demonstrated a statistically significant increase in capillary density in both group A and group B. Moreover, some of the endothelial cells were stained positively for DiI.
  
  
  CONCLUSIONS
  These findings suggest that adipose-derived stem cells have a potential for enhancing the blood supply of random pattern skin flaps. This mechanism might be both the direct differentiation of adipose-derived stem cells into endothelial cells and the indirect effect of angiogenic growth factor released from adipose-derived stem cells.
authors.affiliation: Tokyo, Japan; and Guangzhou, China From the Department of Plastic and Reconstructive Surgery, Nippon Medical School, and Department of Plastic and Reconstructive Surgery, Nanfang Medical University.
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mizuno
authors.forename: Cagri A
authors.initials: CA
authors.lastname: Uysal
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Cai
authors.forename: Rei
authors.initials: R
authors.lastname: Ogawa
authors.forename: Hiko
authors.initials: H
authors.lastname: Hyakusoku
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D000818:Animals; D002454:Cell Differentiation; D006085:Graft Survival / Q000502:physiology; D051379:Mice; D008813:Mice, Inbred ICR; D023421:Models, Animal; D018919:Neovascularization, Physiologic / Q000502:physiology*; D016038:Skin Transplantation / Q000502:physiology*; D013234:Stem Cells / Q000502:physiology*; D013524:Surgical Flaps / Q000098:blood supply*; D014022:Tissue Survival / Q000502:physiology*