The trophic effect of epidermal growth factor on morphological changes and polyamine metabolism in the small intestine of rats

1990 ◽  
Vol 25 (3) ◽  
pp. 328-334 ◽  
Author(s):  
Tomoyuki Tsujikawa ◽  
Tadao Bamba ◽  
Shiro Hosoda
Keyword(s):  
Small Intestine ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Morphological Changes ◽  
Polyamine Metabolism ◽  
Trophic Effect ◽  
Epidermal Growth

Luminal Epidermal Growth Factor is Trophic to the Small Intestine of Parenterally Fed Rats

1995 ◽  
Vol 89 (2) ◽  
pp. 117-120 ◽  
Author(s):  
Tania Marchbank ◽  
Robert A. Goodlad ◽  
Chung Y. Lee ◽  
Raymond J. Playford
Keyword(s):  
Small Intestine ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Parenteral Nutrition ◽  
Trypsin Inhibitor ◽  
Soya Bean ◽  
Trophic Effect ◽  
Bean Trypsin Inhibitor ◽  
Epidermal Growth ◽  
Intestinal Atrophy

1. Intestinal atrophy contributes to the clinical difficulties of patients on parenteral nutrition. Systemic administration of epidermal growth factor reverses this effect, but there is concern over the clinical safety of intravenous administration of growth factors. We therefore investigated whether administration of luminal epidermal growth factor could reverse the atrophy induced in a rat model of parenteral nutrition when epidermal growth factor was given alone or in combination with soya bean trypsin inhibitor to reduce proteolytic digestion of the epidermal growth factor. 2. Infusion of soya bean trypsin inhibitor alone decreased intraluminal tryptic activity by about 90% but did not result in increased proliferation. Intragastric infusion of epidermal growth factor (72 μg/day per rat) caused a 26% increase in proliferation (determined by 2-h metaphase arrest) in the duodenum (P < 0.01) when compared with animals receiving ‘control’ intragastric infusion. However, intragastric epidermal growth factor had no effect on more distal regions of the bowel, probably reflecting rapid proteolysis of the epidermal growth factor by luminal proteases. In contrast, a trophic effect of luminal epidermal growth factor was seen in the duodenum (28% increase, P < 0.01) and jejunum (24% increase, P < 0.05) of animals which had received epidermal growth factor with soya bean trypsin inhibitor. This was probably due to the soya bean trypsin inhibitor decreasing the rate of degradation of epidermal growth factor by intestinal proteases, allowing biologically active epidermal growth factor to reach more distal portions of the bowel. 3. We conclude that luminal administration of epidermal growth factor in combination with protease inhibitors could provide a novel approach to the treatment of intestinal atrophy induced by parenteral nutrition. This approach may also be useful for the treatment of ulceration of the small intestine in conditions such as necrotizing enterocolitis or Crohn's disease. Clinical studies are recommended.

Is polyamine synthesis involved in the proliferative response of the intestinal epithelium to urogastrone-epidermal growth factor?

1989 ◽  
Vol 76 (6) ◽  
pp. 595-598 ◽  
Author(s):  
R. A. Goodlad ◽  
H. Gregory ◽  
N. A. Wright
Keyword(s):  
Cell Proliferation ◽  
Small Intestine ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Proliferative Response ◽  
Intestinal Cell ◽  
Intestinal Epithelial ◽  
Polyamine Synthesis ◽  
Proliferative Effect ◽  
Epidermal Growth

1. Intestinal epithelial cell proliferation was measured in rats maintained on total parenteral nutriton (TPN), in TPN rats given 300 μg of recombinant human epidermal growth factor (urogastrone-epidermal growth factor, URO-EGF) day−1 kg−1, and in further groups given URO-EGF and difluoromethylornithine (DFMO), an inhibitor of the enzyme ornithine decarboxylase (ODC). 2. URO-EGF significantly increased intestinal cell proliferation throughout the gastrointestinal tract. The proliferative response of the colon was particularly pronounced. 3. DFMO reduced the proliferative effect of urogastrone in the stomach and small intestine. DFMO also reduced URO-EGF-stimulated intestinal cell proliferation in the colon, but to a lesser extent. 4. It is concluded that ODC is essential for effecting the proliferative response of the stomach and small intestine to URO-EGF, but this role may be less important in the colon.

Specific receptors for epidermal growth factor in rat intestinal microvillus membranes

1988 ◽  
Vol 254 (3) ◽  
pp. G429-G435 ◽  
Author(s):  
J. F. Thompson
Keyword(s):  
Small Intestine ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Sodium Dodecyl ◽  
Intestinal Lumen ◽  
Scatchard Analysis ◽  
Rat Small Intestine ◽  
Binding Studies ◽  
Epidermal Growth ◽  
Specific Receptors

Epidermal growth factor (EGF) is present in high concentrations in milk, salivary, and pancreaticobiliary secretions. EGF, delivered to the intestinal lumen by these fluids, appears to influence intestinal proliferation. Because EGF exerts its mitogenic effect through binding to specific membrane-bound receptors, binding studies of 125I-labeled EGF to purified microvillus membrane (MVM) preparations from fetal, newborn, and adult rat small intestine were performed. Using the membrane filter technique, binding of 125I-EGF to adult MVM was specific, saturable, and reversible. Adult and fetal MVM binding was rapid and reached a plateau after 30 min at both 20 and 37 degrees C. No binding was detected at 4 degrees C. Specific binding increased linearly from 0 to 75 micrograms MVM protein. Scatchard analysis revealed a single class of receptors in fetal and adult MVM with an association constant of 1.0 +/- 0.35 X 10(9) and 2.3 +/- 1.6 X 10(9) M-1, respectively. Binding capacity was 435.0 +/- 89 and 97.7 +/- 41.3 fmol 125I-EGF bound/mg MVM protein for fetal and adult MVM, respectively. Newborn MVM binding was negligible. After binding, cross-linking utilizing disuccinimidyl suberate, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, autoradiography revealed a 170-kDa receptor. These data demonstrate specific receptors for EGF on MVM of rat small intestine and, thus, suggest a mechanism for the intraluminal regulation of enterocyte proliferation by EGF.

Is glutamine required for the trophic effect of epidermal growth factor?

Surgery ◽  
1995 ◽  
Vol 117 (3) ◽  
pp. 355
Author(s):  
Raymond J. Playford ◽  
Robert A. Goodlaa
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Trophic Effect ◽  
Epidermal Growth

scholarly journals Coactivation of Rac1 and Cdc42 at Lamellipodia and Membrane Ruffles Induced by Epidermal Growth Factor

2004 ◽  
Vol 15 (3) ◽  
pp. 1003-1010 ◽  
Author(s):  
Kazuo Kurokawa ◽  
Reina E. Itoh ◽  
Hisayoshi Yoshizaki ◽  
Yusuke Ohba Takeshi Nakamura ◽  
Michiyuki Matsuda
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Morphological Changes ◽  
Critical Role ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
A431 Cells ◽  
Major Function ◽  
Membrane Ruffling ◽  
Epidermal Growth

A major function of Rho-family GTPases is to regulate the organization of the actin cytoskeleton; filopodia, lamellipodia, and stress fiber are regarded as typical phenotypes of the activated Cdc42, Rac, and Rho, respectively. Using probes based on fluorescent resonance energy transfer, we report on the spatiotemporal regulation of Rac1 and Cdc42 at lamellipodia and membrane ruffles. In epidermal growth factor (EGF)-stimulated Cos1 and A431 cells, both Rac1 and Cdc42 were activated diffusely at the plasma membrane, followed by lamellipodial protrusion and membrane ruffling. Although Rac1 activity subsided rapidly, Cdc42 activity was sustained at lamellipodia. A critical role of Cdc42 in these EGF-induced morphological changes was demonstrated as follows. First, phorbol 12-myristate 13-acetate, which activated Rac1 but not Cdc42, could not induce full-grown lamellipodia in Cos1 cells. Second, a GTPase-activating protein for Cdc42, KIAA1204/CdGAP, inhibited lamellipodial protrusion and membrane ruffling without interfering with Rac1 activation. Third, expression of the Cdc42-binding domain of N-WASP inhibited the EGF-induced morphological changes. Therefore, Rac1 and Cdc42 seem to synergistically induce lamellipodia and membrane ruffles in EGF-stimulated Cos1 cells and A431 cells.

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