Epidermal growth factor upregulates intestinal electrolyte and nutrient transport

Abstract

The role of epidermal growth factor (EGF) in the acute regulation of intestinal transport of electrolytes and glucose was examined. In vivo transport studies were performed in New Zealand White rabbits (500-900 g) using a single-pass perfusion technique. In vitro net fluxes were determined under short-circuited conditions in Ussing chambers. Kinetic parameters of glucose transport in the presence and absence of EGF were measured in brush-border membrane vesicles. In vivo studies showed that the addition of 60 ng/ml EGF to the perfusate resulted in increased absorption of H2O, Na+, Cl-, and glucose from the jejunum. In Ussing chambers, the presence of EGF caused an increase in jejunal net fluxes of glucose-stimulated Na+ and 3-O-methylglucose due to an increase in mucosal-to-serosal movements. Verapamil abolished the EGF effect. In the absence of glucose, net fluxes of Na+ and Cl- were enhanced in the presence of EGF due to a decrease in the serosal-to-mucosal movement of both ions. Verapamil had no effect on this decrease. The incubation of EGF with brush-border membrane vesicles had no effect on either the maximal flux or the Michaelis constant of glucose transport. These results indicate that EGF is capable of regulating absorption of electrolytes and nutrients from the small intestine and suggest a role for this peptide in the control of intestinal transport.

Epidermal growth factor inhibits intestinal NHE8 expression via reducing its basal transcription

“…Loss of EGF or overexpression of EGF cause growth retardation (34). In the intestine, this hormone is known to accelerate intestinal maturation and to enhance Na ϩ absorption (25,31,34). Although EGF has been shown to stimulate intestinal NHE2 activity, it was unclear whether EGF affects intestinal NHE8 expression.…”

“…Epidermal growth factor (EGF), an important growth factor found in many human tissues, induces cell division, DNA synthesis, tissue proliferation, and cellular differentiation. It can also cause changes in electrolyte and nutrient absorption (13,25,37). EGF stimulates NHE1 activity in the gastrointestinal tract and other organs (8,16,17,22,23).…”

Oral Transforming Growth Factor-α Enhances Jejunal Mucosal Recovery and Electrical Resistance in Piglet Rotavirus Enteritis

“…4), we conclude that TGFa may stimulate villus elongation and resistance of the intestinal barrier. Acutely administered EGF also increased transepithelial resistance in the rabbit ileum, in some of the studies of Opleta-Madsen et al (37). There is other evidence suggesting that activation of the EGFITGFa receptor could change mucosal barrier function.…”

Biomechanical properties of ileum after systemic treatment with epithelial growth factor

“…The derived material constants a 1 , a 2 , a 4 , and C from the strain energy function are illustrated in EGF treatment had the lowest circumferential stiffness and comparatively high longitudinal stiffness, and that the remodeling was most significant in the 7 days' EGF treatment group.…”

“…Throughout the last decade, the pharmacological potential of systemic treatment of EGF has been explored [2] . In the gastrointestinal tract, EGF causes growth, inhibits gastric acid secretion, and leads to changes in electric potentials, enzyme activity and transport of amino acids [3][4][5][6] . Due to the pronounced effects on intestinal mucosa, the therapeutic potential of systemic treatment of EGF has been explored in animal experiments.…”