G protein-coupled receptor120 (GPR120) transcription in intestinal epithelial cells is significantly affected by bacteria belonging to the Bacteroides, Proteobacteria, and Firmicutes phyla.
Free fatty acids (FFA) are produced in the intestine by microbial fermentation. Recently, a family of G protein-coupled receptors (GPR) acting as FFA transporters has been reported including GPR120, which is expressed by intestinal epithelial cells. The GPR120 has been reported to affect the expression of glucagon-like peptide (GLP)-1 as well as function as a control point for anti-inflammatory effects. The aim of the present study was to evaluate whether 12 selected intestinal bacteria, representing the 4 major phyla present in the intestine, affect intestinal epithelial cell GPR120 and GLP-1 mRNA abundance. Supernatants of the 12 bacteria were added to differentiated Caco-2 intestinal epithelial cells cultured on filter inserts in concentrations corresponding to a cell:bacteria ratio of 1:200. After 4 h of incubation, changes in cellular mRNA of GLP-1 and GPR120 by bacterial supernatant were examined using real-time reverse transcriptase polymerase chain reaction. The abundance of GLP-1 mRNA decreased when cells were exposed to 4 of the 12 supernatants (P ≤ 0.05) compared with cells without bacteria added. Supernatants from 8 of the 12 bacteria analyzed increased the mRNA level of GPR120 (P ≤ 0.05) compared with cells without bacteria added. The alteration in cellular GPR120 mRNA was observed with bacteria categorized as either probiotics or bacteria capable of inducing an anti-inflammatory effect. The beneficial effect of these bacteria may very well be mediated by regulation of GPR120. The regulation of GPR120 by intestinal microbiota represents a direct signaling pathway for gut bacteria to affect host health and metabolism.
Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark.
M
M
Fredborg
P K
PK
Theil
B B
BB
Jensen
S
S
Purup
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001439:Bacteroides; D004032:Diet / Q000662:veterinary; D004847:Epithelial Cells / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D007413:Intestinal Mucosa / Q000166:cytology* / Q000382:microbiology*; D020560:Proteobacteria; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*; D013552:Swine
D043562:Receptors, G-Protein-Coupled