Influence of insulin therapy on burn wound healing in rats.
BACKGROUND
Insulin is proposed as a therapy for suppressing muscle wasting after burn trauma although the long-term effects of this therapy on wound healing are not yet known. The present study was designed to investigate the effect of systemically administered insulin therapy on burn wound healing.


METHODS
Young rats weighing 80-150 g were subjected to 15-20% total body surface area burn injury on their shaved dorsum. The insulin dosage was increased over the first 3 days in each rat from 0.25 U (Day 1), 0.5 U (Day 2), and 1.0 U (Day 3) per 100 g body wt. The rats were euthanized at the fourth or fifteenth day postinjury. Skin sections were analyzed by histochemistry and quantitative polarization microscopy.


RESULTS
Histology showed a decreased number of inflammatory cells and increased vasodilation in the insulin-treated animals at Day 4 relative to untreated rats; at Day 15 there was increased reepithelialization. Quantitative analysis using polarization microscopy and picrosirius red staining showed an increased collagen deposition in wounds by Day 4 in insulin-treated rats relative to untreated burn controls.


CONCLUSIONS
These results indicate that insulin induces accelerated wound healing associated with diminished inflammation and increased collagen deposition.
Madibally
Sundararajan V
SV
Shriners Burns Hospital, Surgical Services and the Center for Engineering in Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, Massachusetts 02114, USA.
Solomon
Vered
V
Mitchell
Richard N
RN
Van De Water
Livingston
L
Yarmush
Martin L
ML
Toner
Mehmet
M
D000818:Animals; D002056:Burns / Q000188:drug therapy* / Q000473:pathology; D003094:Collagen / Q000096:biosynthesis; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007249:Inflammation; D007328:Insulin / Q000627:therapeutic use*; D008297:Male; D023421:Models, Animal; D018919:Neovascularization, Physiologic / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D014664:Vasodilation / Q000187:drug effects; D014945:Wound Healing / Q000187:drug effects* / Q000502:physiology
D007004:Hypoglycemic Agents; D007328:Insulin; D003094:Collagen