Peptide YY and proglucagon mRNA expression patterns and regulation in the gut.
OBJECTIVE
Peptide YY (PYY) and glucagon-like peptide-1 are important in the control of energy homeostasis and are both secreted from the gut in response to ingested nutrients. However, more studies are needed on nutrient regulation of their gene expression patterns in specific areas of the gut. This study detailed PYY and proglucagon (the gene that encodes glucagon-like peptide-1) gene expression patterns and regulation in the gut. We further examined the regulation of PYY and proglucagon mRNA by a diet containing fermentation-resistant starch (in vivo) and butyrate (in vitro).


METHODS
Quantitative real time reverse transcriptase-polymerase chain reaction was used to measure PYY and proglucagon gene expression in epithelial cells collected from the duodenum, jejunum, cecum, and colon in normal Sprague-Dawley rats and in rats fed a resistant starch diet for 4 weeks. The same measurements were also performed in primary epithelial cells collected from the cecum and colon of normal rats after the cells were incubated with butyrate for 3 hours.


RESULTS
The gene expression patterns for PYY and proglucagon are similar to their peptide distribution patterns in the gut. Also, PYY and proglucagon mRNA expression were up-regulated in the cecum and colon in resistant-starch-fed rats. Butyrate increased PYY and proglucagon gene expression in a dose-dependent manner in vitro.


CONCLUSIONS
Our data provide evidence that the distal part of the gut has the ability to sense nutrients such as butyrate, resulting in the up-regulation of PYY and proglucagon gene expression.
Zhou
Jun
J
Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
Hegsted
Maren
M
McCutcheon
Kathleen L
KL
Keenan
Michael J
MJ
Xi
Xiaochun
X
Raggio
Anne M
AM
Martin
Roy J
RJ
D000818:Animals; D001069:Appetite Regulation; D002087:Butyrates / Q000494:pharmacology; D002334:Carnitine O-Palmitoyltransferase / Q000378:metabolism; D002432:Cecum / Q000378:metabolism; D003106:Colon / Q000378:metabolism; D004032:Diet; D004386:Duodenum / Q000378:metabolism; D064429:Fatty Acid Synthases / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D005941:Glucokinase / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D051273:Glucose Transporter Type 2 / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism*; D007583:Jejunum / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D027501:Monocarboxylic Acid Transporters / Q000378:metabolism; D019894:Peptide YY / Q000378:metabolism*; D052336:Proglucagon / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013213:Starch / Q000008:administration & dosage; D027981:Symporters / Q000378:metabolism; D000099233:Monocarboxylate Transport Protein 1
D002087:Butyrates; D002334:Carnitine O-Palmitoyltransferase; D064429:Fatty Acid Synthases; D005941:Glucokinase; D005947:Glucose; D051273:Glucose Transporter Type 2; D027501:Monocarboxylic Acid Transporters; D019894:Peptide YY; D052336:Proglucagon; D013213:Starch; D027981:Symporters; D000099233:Monocarboxylate Transport Protein 1; C495683:Slc2a2 protein, rat