Effects of glucagon-like peptides 1 and 2 and epidermal growth factor on the epithelial barrier of the rumen of adult sheep.
J Anim Physiol Anim Nutr (Berl)
; 103(6): 1727-1738, 2019 Nov.
Article
em En
| MEDLINE
| ID: mdl-31498510
ABSTRACT
Epidermal growth factor (EGF) and glucagon-like peptides (GLP) modulate the tight junctions (TJ) of the intestinal epithelial barrier (EB) of monogastric animals. This work tried to elucidate whether GLP-1, GLP-2 and EGF can affect the EB of the rumen. Ovine ruminal epithelia were incubated in Ussing chambers for 7 hr with 25 or 250 nM of either GLP-1 or GLP-2 on the serosal side, with 2.5 nM of EGF on the serosal side or with 0.25 or 2.5 nM EGF on the mucosal side. No treatment affected tissue conductance. Short-circuit current (Isc ) was affected by time and treatment and their interactions. Only 250 nM of either GLP-1 or GLP-2 decreased Isc in certain periods compared with 25 nM GLP-1 or 0.25 nM mucosally applied EGF; however, not when compared to control epithelia. Fluorescein flux rates (Jfluor ) of ruminal epithelia were affected by treatment, time and time × treatment interaction. The time × treatment interaction was based on an increase in Jfluor between the first and last hour in epithelia incubated with 25 nM GLP-1 or GLP-2 and in epithelia incubated with EGF. After 7 hr incubation, claudin-7 mRNA expression was downregulated in all treatments. Claudin-1 mRNA was upregulated after incubation with 2.5 nM EGF on the serosal side, claudin-4 mRNA was downregulated by 2.5 nM EGF on the mucosal side, and occludin mRNA was increased after incubation with 250 nM GLP-2. The protein abundance of all tested TJ proteins was not influenced by treatment. We conclude that GLP-1, GLP-2, and EGF have no obvious acute effects on the EB of ruminal epithelia under simulated physiological conditions ex vivo. However, by decreasing the mRNA expression of claudin-7 and partly affecting other TJ proteins, they may modulate EB in the longer term or under certain conditions.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Rúmen
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Fator de Crescimento Epidérmico
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Peptídeo 1 Semelhante ao Glucagon
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Peptídeo 2 Semelhante ao Glucagon
Limite:
Animals
Idioma:
En
Revista:
J Anim Physiol Anim Nutr (Berl)
Assunto da revista:
CIENCIAS DA NUTRICAO
/
FISIOLOGIA
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MEDICINA VETERINARIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Alemanha