Abdominal wall repair is delayed during hepatic regeneration.
BACKGROUND
Abdominal wall wound failure remains a common surgical problem. The signals that activate normal fibroplastic repair versus regeneration pathways are unknown. Transforming growth factor beta levels rise during incisional healing but fall during hepatic regeneration. Changes in the injured host cytokine milieu may therefore differentially effect abdominal wall repair versus hepatic regeneration.


METHODS
Forty-eight rats were divided into four groups (n = 12). Groups 1-3 underwent sham celiotomy, 70% hepatectomy, or 80% enterectomy with anastamosis. Incisions from Group 4 were treated with either 1 microg of transforming growth factor beta(2) (TGF-beta(2)) or vehicle following hepatectomy. Isolated fascial and dermal incisions were harvested and tested for breaking strength on POD 7. Serum (TGF-beta(2)) and hepatocyte growth factor (HGF) levels were measured by ELISA.


RESULTS
Recovery of incisional wound breaking strength was delayed following hepatectomy but not enterectomy (P<0.002). The inhibitory effect was observed in both the fascia and the dermis of the abdominal wall. TGF-beta(2) levels were depressed in hepatectomy animals on POD 7, while at the same time HGF levels were elevated. Exogenous TGF-beta(2) shifted the healing trajectory of deficient wounds back toward a control pattern.


CONCLUSIONS
Abdominal wall fascial and dermal healing is delayed during hepatic regeneration. Elevated HGF and depressed TGF-beta(2) suggest a host mechanism that prioritizes hepatic parenchymal regeneration over fibroplastic repair (scar). Observations such as these are needed as therapeutic wound healing enters the clinical realm.
Kuhn
M A
MA
Institute for Tissue Regeneration, Repair, and Rehabilitation, Bay Pines Veterans Affairs Medical Center, Bay Pines, Florida, 33744, USA.
Smith
P D
PD
Wachtel
T L
TL
Wright
T E
TE
Rogazewski
A
A
Nguyen
K
K
Robson
M C
MC
Franz
M G
MG
D000009:Abdominal Muscles / Q000293:injuries*; D000818:Animals; D001835:Body Weight; D004435:Eating; D006498:Hepatectomy; D017228:Hepatocyte Growth Factor / Q000097:blood; D008115:Liver Regeneration; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000097:blood; D014945:Wound Healing
D016212:Transforming Growth Factor beta; D017228:Hepatocyte Growth Factor