Early weaning accelerates the differentiation of mucous neck cells in rat gastric mucosa: possible role of TGFalpha/EGFR.
The development of the gastric mucosa is controlled by hormones, growth factors and feeding behavior. Early weaning (EW), which means the abrupt interruption of suckling, increases proliferation and differentiation in the rat gastric epithelium. Transforming growth factor alpha (TGFalpha) is secreted in the stomach, binds to the epidermal growth factor receptor (EGFR) and may control cell proliferation, differentiation and migration. Here, we investigated the influence of suckling-weaning transition on the differentiation of mucous neck cells in the stomach and its association to the expression of TGFalpha and EGFR. Fifteen-day-old Wistar rats were divided into two groups: suckling (control), in which pups were kept with the dam, and early weaning (EW), in which rats were separated from their mother and fed with hydrated powdered chow. TGFalpha and EGFR levels were increased at 18 days in EW animals compared to control ones (p<0.05). Histochemical reactions with Periodic Acid-Schiff reagent+Alcian Blue or Bandeiraea simplicifolia II lectin were used to stain the mucous neck cells and showed an increase in this cell population throughout EW, which was more pronounced at 17 days when compared to suckling pups (p<0.05). These morphological results were confirmed by RT-PCR for mucin 6. The levels of mucin 6 mRNA were higher in EW animals from the 16th to the 18th day (1-3 days post-weaning) when compared to the respective control group. Inhibition of EGFR through AG1478 administration to EW animals prevented the expansion of mucous neck cell population induced by EW (p<0.05). Therefore, early weaning up regulated TGFalpha/EGFR expression and induced differentiation of mucous neck cells. Moreover, we showed that EGFR takes part in the maturation of this cell population. We conclude that regular suckling-weaning transition is crucial to guarantee the development of the gastric mucosa.
Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, Av Prof Lineu Prestes 1524 ICB I 05508-900 São Paulo, SP, Brazil.
Luciana H
LH
Osaki
Marco A F
MA
Curi
Eliana P
EP
Alvares
Patrícia
P
Gama
D000818:Animals; D015153:Blotting, Western; D002454:Cell Differentiation; D002478:Cells, Cultured; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000502:physiology*; D005260:Female; D005753:Gastric Mucosa / Q000166:cytology* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D007124:Immunoenzyme Techniques; D055272:Mucin-6 / Q000235:genetics; D011799:Quinazolines; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016211:Transforming Growth Factor alpha / Q000502:physiology*; D020032:Tyrphostins / Q000494:pharmacology; D014886:Weaning
D055272:Mucin-6; D011799:Quinazolines; D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha; D020032:Tyrphostins; C101044:RTKI cpd; D066246:ErbB Receptors