MMPs and TIMP-1 are differentially expressed between acute murine excisional and laser wounds.
OBJECTIVE
Matrix metalloproteinases (MMPs) and their physiological inhibitors, the tissue inhibitors of metalloproteinases (TIMPs) play significant roles in wound repair. The aim of this study was to determine whether MMP and TIMP-1 mRNA is differentially expressed between laser-created and excisional skin wounds.


METHODS
Full-thickness wounds were created on the dorsal surface of Balb/c mice by either excision of the skin or with a CO2 laser. Animals were sacrificed at days 1, 3, 5, 7, 10, and 13, and their wounds processed for RNA isolation or histology and immunohistochemistry.


RESULTS
Northern hybridization for MMP-3, -10, -13, and TIMP-1 mRNA demonstrated higher expression on days 1, 3, and 5 in the laser wounds as compared to the excisional wounds. Histological evaluation revealed a two day delay in the resurfacing of laser wounds as compared to excisional wounds. Immunohistochemistry of Day 5 and 7 excisional and laser wounds showed MMP-3 within the epidermal compartment and the neo-dermis. No remarkable differences were noted in the spatial distribution patterns of MMP-3 between wound types.


CONCLUSIONS
Our findings demonstrate that MMPs and TIMP-1 mRNA expression is higher on days 1-5 post injury in full thickness laser-created wounds than in comparable same day excisional wounds.
Draper
Bradley K
BK
Department of Medicine (Dermatology), Vanderbilt University School of Medicine, Nashville, Tennessee, USA. bradley.draper@mcmail.vanderbilt.edu
Davidson
Mari K
MK
Nanney
Lillian B
LB
D000818:Animals; D015152:Blotting, Northern; D005786:Gene Expression Regulation / Q000235:genetics; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D007150:Immunohistochemistry; D007700:Kinetics; D053685:Laser Therapy; D020782:Matrix Metalloproteinases / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger / Q000378:metabolism; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing; D014947:Wounds and Injuries / Q000209:etiology* / Q000378:metabolism*
D012333:RNA, Messenger; D019715:Tissue Inhibitor of Metalloproteinase-1; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D020782:Matrix Metalloproteinases