title: Molecular imaging-assisted optimization of hsp70 expression during laser-induced thermal preconditioning for wound repair enhancement.
abstract: Patients at risk for impaired healing may benefit from prophylactic measures aimed at improving wound repair. Several photonic devices claim to enhance repair by thermal and photochemical mechanisms. We hypothesized that laser-induced thermal preconditioning would enhance surgical wound healing that was correlated with hsp70 expression. Using a pulsed diode laser (lambda=1.85 microm, tau(p)=2 ms, 50 Hz, H=7.64 mJ cm(-2)), the skin of transgenic mice that contain an hsp70 promoter-driven luciferase was preconditioned 12 hours before surgical incisions were made. Laser protocols were optimized in vitro and in vivo using temperature, blood flow, and hsp70-mediated bioluminescence measurements as benchmarks. Biomechanical properties and histological parameters of wound healing were evaluated for up to 14 days. Bioluminescent imaging studies indicated that an optimized laser protocol increased hsp70 expression by 10-fold. Under these conditions, laser-preconditioned incisions were two times stronger than control wounds. Our data suggest that this molecular imaging approach provides a quantitative method for optimization of tissue preconditioning and that mild laser-induced heat shock may be a useful therapeutic intervention prior to surgery.
authors.affiliation: Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37232, USA.
authors.forename: Gerald J
authors.initials: GJ
authors.lastname: Wilmink
authors.forename: Susan R
authors.initials: SR
authors.lastname: Opalenik
authors.forename: Joshua T
authors.initials: JT
authors.lastname: Beckham
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Abraham
authors.forename: Lillian B
authors.initials: LB
authors.lastname: Nanney
authors.forename: Anita
authors.initials: A
authors.lastname: Mahadevan-Jansen
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Davidson
authors.forename: E Duco
authors.initials: ED
authors.lastname: Jansen
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003094:Collagen / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature; D007150:Immunohistochemistry; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D007834:Lasers; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D051381:Rats; D012306:Risk; D012867:Skin / Q000528:radiation effects; D014945:Wound Healing
chemical_list: D018840:HSP70 Heat-Shock Proteins; D003094:Collagen