Effect of growth factors on epithelial restitution of human colonic mucosa in vitro.
BACKGROUND
Epithelial restitution enables resurfacing of epithelial discontinuities by enterocyte migration. This study investigated the effect of basic fibroblast growth factor (bFGF), insulin-like growth factor (IGF-1), and epidermal growth factor (EGF) on restitution of human colonic mucosa in vitro.


METHODS
After base-line incubation human colonic mucosal strips, mounted in Ussing chambers, were luminally exposed to 0.5 mM sodium deoxycholate (NaDOC) for 10 min. Thereafter tissues were incubated with buffer alone or luminal buffer containing various concentrations of bFGF, IGF-1, and EGF for 3 h. Resistance (R) was calculated from potential difference (PD) and short-circuit current (Isc). All tissues were processed for light microscopy. Extent of damage was measured by morphometry.


RESULTS
Luminal 0.5 mM NaDOC for 10 min caused R to drop by 43% (n = 4; P < 0.05). Compared with controls 50 ng/ml EGF induced an approximately 30% R increase until the end of the experiments (P < 0.05, n = 4, paired). Ten minutes after injury 50.2 +/- 4% of the mucosa was damaged (n = 6), and after 3 h damage was significantly reduced by EGF (17.2 +/- 3% versus 31.7 +/- 4%, 50 ng/ml EGF versus controls) (P < 0.05, n = 6 per group). Histology showed that EGF stimulated enterocyte migration over the basal lamina. Various doses of bFGF and IGF-1 did not impair restitution when compared with controls.


CONCLUSIONS
In contrast to bFGF and IGF-1, EGF was shown to promote epithelial restitution of human colonic mucosa in vitro.
Riegler
M
M
University Clinic of Surgery, University of Vienna, Austria.
Sedivy
R
R
Sogukoglu
T
T
Cosentini
E
E
Bischof
G
G
Teleky
B
B
Feil
W
W
Schiessel
R
R
Hamilton
G
G
Wenzl
E
E
D003106:Colon / Q000187:drug effects* / Q000473:pathology; D004594:Electrophysiology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D004848:Epithelium; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D018709:Statistics, Nonparametric
D006133:Growth Substances; D016222:Fibroblast Growth Factor 2; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I