Effect of unfocused extracorporeal shock wave therapy on growth factor gene expression in wounds and intact skin of horses.
OBJECTIVE
To compare the effect of extracorporeal shock wave therapy (ESWT) on expression of fibroblast growth factor-7 (FGF-7), transforming growth factor-β1 (TGF-β1), insulin-like growth factor-1 (IGF-1), platelet-derived growth factor-A (PDGF), and vascular endothelial growth factor-A (VEGF) in skin with surgically created skin wounds and intact skin in horses.


METHODS
14 healthy horses.


METHODS
8 horses were treated with ESWT at 6 locations along the neck at 36, 24, 12, 6, 2, or 1 hour prior to collection of full-thickness biopsy specimens from each location; a control specimen was collected from a sham-treated location. In 6 horses, 5 full-thickness wounds were created in each forelimb. Wounds in 1 forelimb/horse received ESWT immediately after creation and subsequently on days 7, 14, and 21; wounds in the contralateral forelimb remained untreated. Biopsy specimens were collected from 1 wound on each forelimb on days 7, 14, 21, 28, and 35. Expression levels of FGF-7, TGF-β1, IGF-1, PDGF, and VEGF were assessed in tissue samples from the horses' necks and forelimbs.


RESULTS
In surgically created wounds, ESWT treatment was associated with reduced TGF-β1 expression, compared with expression in control wounds, during the entire study period. At 28 days following wound creation, IGF-1 expression was significantly increased for treated and untreated wounds, compared with findings on days 7, 14, 21, and 35. There was no significant effect of treatment on FGF-7, TGF-β1, IGF-1, PDGF, or VEGF expression in intact skin.


CONCLUSIONS
Intervention with ESWT to suppress TGF-β1 may decrease granulation tissue production, resulting in improved wound healing on the distal portion of horses' limbs.
Department of Clinical Studies, Ontario Veterinary College, University of Guelph, N1G 2W1 Guelph, ON, Canada.
Kaitlyn A
KA
Link
Judith B
JB
Koenig
Andressa
A
Silveira
Brandon L
BL
Plattner
Brandon N
BN
Lillie
D000818:Animals; D005260:Female; D005552:Forelimb / Q000293:injuries / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects; D005786:Gene Expression Regulation / Q000528:radiation effects*; D006097:Granulation Tissue / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D019220:High-Energy Shock Waves / Q000627:therapeutic use*; D006736:Horses / Q000293:injuries*; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects*; D008297:Male; D009333:Neck / Q000473:pathology / Q000528:radiation effects; D019838:Neck Injuries / Q000378:metabolism / Q000473:pathology; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012867:Skin / Q000293:injuries / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects*; D013997:Time Factors; D014945:Wound Healing / Q000528:radiation effects*
D036341:Intercellular Signaling Peptides and Proteins