Expression patterns of l-amino acid receptors in the murine STC-1 enteroendocrine cell line

  • Hongxia Wang
  • Karnam S. Murthy
  • John R. GriderEmail author
Regular Article


Regulation of gut function depends on the detection and response to luminal contents. Luminal l-amino acids (l-AA) are detected by several receptors including metabotropic glutamate receptors 1 and 4 (mGluR1 and mGluR4), calcium-sensing receptor (CaSR), GPRC family C group 6 subtype A receptor (GPRC6A) and umami taste receptor heterodimer T1R1/T1R3. Here, we show that murine mucosal homogenates and STC-1 cells, a murine enteroendocrine cell line, express mRNA for all l-AA receptors. Immunohistochemical analysis demonstrated the presence of all l-AA receptors on STC-1 with CaSR being most commonly expressed and T1R1 least expressed (35% versus 15% of cells); mGluRs and GPRC6a were intermediate (~ 20% of cells). Regarding coexpression of l-AA receptors, the mGluRs and T1R1 were similarly coexpressed with CaSR (10–12% of cells) whereas GPRC6a was coexpressed least (7% of cells). mGluR1 was coexpressed with GPRC6a in 11% of cells whereas coexpression between other receptors was less (2–8% of cells). CaSR and mGluR1 were coexpressed with glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) in 20–25% of cells whereas T1R1 and GPRC6a were coexpressed with GLP-1 and PYY less (8–12% of cells). Only mGluR4 showed differential coexpression with GLP-1 (13%) and PYY (21%). l-Phenylalanine (10 mM) caused a 3-fold increase in GLP-1 release, which was strongly inhibited by siRNA to CaSR indicating functional coupling of CaSR to GLP-1 release. The results suggest that not all STC-1 cells express (and coexpress) l-AA receptors to the same extent and that the pattern of response likely depends on the pattern of expression of l-AA receptors.


Enteroendocrine cells Taste receptors l-Amino acid receptors STC-1 cells Neurohumoral peptides 


Funding information

This work was supported by the National Institute of Diabetes and Digestive and Kidney Diseases grants DK-15564 (KSM), DK-28300 (KSM) and DK-34153 (JRG). This work was also supported by grants to the Virginia Commonwealth University from the National Center for Advancing Translational Sciences UL1TR002649 (HW) and the Center for Clinical and Translational Research Endowment Fund of Virginia Commonwealth University (HW).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All applicable international, national and institutional guidelines for the care and use of animals were followed. All animal procedures were performed according to a protocol approved by the Institutional Animal Care and Use Committee of Virginia Commonwealth University.


  1. Acar I, Cetinkaya A, Lay I, Ileri-Gurel E (2018) The role of calcium sensing receptors in GLP-1 and PYY secretion after acute intraduodenal administration of L-tryptophan in rats. Nutr Neurosci dio.
  2. Akiba Y, Inoue T, Kaji I, Higashiyama M, Narimatsu K, Iwamoto K, Watanabe M, Guth PH, Engel E, Kuwahara A, Kaunitz JD (2015) Short-chain fatty acid sensing in rat duodenum. J Physiol 593:585–599CrossRefPubMedPubMedCentralGoogle Scholar
  3. Alamshah A, Spreckley E, Norton M, Kinsey-Jones JS, Amin A, Ramgulam A, Cao Y, Johnson R, Saleh K, Akalestou E, Malik Z, Gonzalez-Abuin N, Jomard A, Amarsi R, Moolla A, Sargent PR, Gray GW, Bloom SR, Murphy KG (2017) L-phenylalanine modulates gut hormone release and glucose tolerance and suppresses food intake through the calcium-sensing receptor in rodents. Int J Obesity 41:1693–1701CrossRefGoogle Scholar
  4. Avau B, Rotondo A, Thijs T, Andrews CN, Janssen P, Tack J, Depoortere I (2015) Targeting extra-oral bitter taste receptors modulates gastrointestinal motility with effects on satiation. Sci Rep 5:15985. CrossRefPubMedPubMedCentralGoogle Scholar
  5. Bala V, Rajagopal S, Kumar DP, Nalli AD, Mahavadi S, Sanyal AJ, Grider JR, Murthy KS (2014) Release of GLP-1 and PYY in response to the activation of G protein-coupled bile acid receptor TGR5 is mediated by Epac/PLC-ε pathway and modulated by endogenous H2S. Front Physiol 5:420. CrossRefPubMedPubMedCentralGoogle Scholar
  6. Bellono NW, Bayrer JR, Leitch DB, Castro J, Zhang C, O’Donnell TA, Brierley SM, Ingraham HA, Julius D (2017) Enterochromaffin cells are gut chemosensors that couple to sensory neural pathways. Cell 170:185–198CrossRefPubMedPubMedCentralGoogle Scholar
  7. Beumer J, Artegiani B, Post Y, Reimann F, Gribble F, Nguyen TN, Zeng H, Van den Born M, Van Es JH, Clevers H (2018) Enteroendocrine cells switch hormone expression along the crypt-to-villus BMP signaling gradient. Nature Cell Biol20:909–916Google Scholar
  8. Bezencon C, leCoutre J, Demak S (2007) Taste-signaling proteins are coexpressed in solitary intestinal epithelial cells. Chem Sens 32:41–49CrossRefGoogle Scholar
  9. Bohórquez DV, Shahid RA, Erdmann A, Kreger AM, Wang Y, Calakos N, Wang F, Liddle RA (2015) Neuroepithelial circuit formed by innervation of sensory enteroendocrine cells. J Clin Invest 125:782–786CrossRefPubMedPubMedCentralGoogle Scholar
  10. Choi S, Lee M, Shiu AL, Yo SJ, Aponte GW (2007) Identification of a protein hydrolysate responsive G protein-coupled receptor in enterocytes. Am J Phys 292:G98–G112CrossRefGoogle Scholar
  11. Clemmensen C, Smajilovic S, Wellendorph P, Brauner-Osborne H (2014) The GPCR, class C, group 6, subtype A (GPRC6A) receptor: from cloning to physiological function. Br J Pharmacol 171:1129–1141CrossRefPubMedPubMedCentralGoogle Scholar
  12. Cox HM (2016) Neuroendocrine peptide mechanisms controlling intestinal epithelial function. Curr Opin Pharmacol 31:50–56CrossRefPubMedGoogle Scholar
  13. Daly K, Al-Rammahi M, Moran A, Marcello M, Ninomiya Y, Shirazi-Beechey SP (2013) Sensing of amino acids by the gut-expressed taste receptor T1R1-T1R3 stimulated CCK secretion. Am J Phys 304:G271–G282Google Scholar
  14. Diakogiannaki E, Pais R, Tolhurst G, Parker HE, Horscroft J, Rauscher B, Zietek T, Daniel H, Gribble FM, Reimann F (2013) Oligopeptides stimulate glucagon-like peptide-1 secretion in mice through proton-coupled uptake and the calcium-sensing receptor. Diabetologia 56:2688–2696CrossRefPubMedPubMedCentralGoogle Scholar
  15. Dyer J, Salmon KS, Zibrik L, Shirazi-Beechey SP (2005) Expression of sweet taste receptors of the T1R family in the intestinal tract and enteroendocrine cells. Biochem Soc Trans 33:302–305CrossRefPubMedGoogle Scholar
  16. Egerod KL, Engelstoft MS, Grunddal KV, Nøhr MK, Secher A, Sakata I, Pedersen J, Windeløv JA, Füchtbauer EM, Olsen J, Sundler F, Christensen JP, Wierup N, Olsen JV, Holst JJ, Zigman JM, Poulsen SS, Schwartz TW (2012) A major lineage of enteroendocrine cells coexpress CCK, secretin, GIP, GLP-1, PYY and neurotensin but not somatostatin. Endocrinology 153:5782–5795CrossRefPubMedGoogle Scholar
  17. Fothergill LJ, Callaghan B, Hunne B, Bravo DM, Furness JB (2017) Costorage of enteroendocrine hormones evaluated at the cell and subcellular levels in male mice. Endocrinology 158:2113–2123CrossRefPubMedGoogle Scholar
  18. Gribble FM, Reimann F (2016) Enteroendocrine cells: chemosensors in the intestinal epithelium. Annu Rev Physiol 78:277–299CrossRefPubMedGoogle Scholar
  19. Gribble FM, Reimann F (2017) Signaling in the gut endocrine axis. Physiol Behav 176:183–188CrossRefPubMedGoogle Scholar
  20. Gwynne RM, Bornstein JC (2007) Mechanisms underlying nutrient-induced segmentation in isolated guinea pig small intestine. Am J Phys 292:G1162–G1172Google Scholar
  21. Gwynne RM, Ly KDND, Parry LJ, Bornstein JC (2017) Calcium sensing receptors mediate local inhibitory reflexes evoked by L-phenylalanine in guinea pig jejunum. Front Physiol 8:991. CrossRefPubMedPubMedCentralGoogle Scholar
  22. Haber AL, Biton M, Rogel N, Herbst RH, Shekhar K, Smillie C, Burgin G, Delorey TM, Howitt MR, Katz Y, Tirosh I, Beyaz S, Dionne D, Zhang M, Raychowdhury R, Garrett WS, Rozenblatt-Rosen O, Shi HN, Yilmaz O, Xavier RJ, Regev A (2017) A single-cell survey of the small intestinal epithelium. 551:333–339Google Scholar
  23. Habib AM, Richards P, Cairns LS, Rogers GJ, Bannon CA, Parker HE, Morley TC, Yeo GS, Reimann F, Gribble FM (2012) Overlap of endocrine hormone expression in the mouse intestine revealed by transcriptional profiling and flow cytometry. Endocrinology 153:3054–3065CrossRefPubMedPubMedCentralGoogle Scholar
  24. Kaji I, Kaunitz JD (2017) Luminal chemosensing in the gastroduodenal mucosa. Curr Opin Gastroenterol 33:439–445CrossRefPubMedPubMedCentralGoogle Scholar
  25. Kendig DM, Hurst NR, Bradley ZL, Mahavadi S, Kuemmerle JF, Lyall V, DeSimone J, Murthy KS, Grider JR (2014) Activation of the umami taste receptor (T1R1/T1R3) initiates the peristaltic reflex and pellet propulsion in the distal colon. Am J Phys 307:G1100–G1107Google Scholar
  26. Kuhre RE, Wewer Albrechtsen NJ, Deacon CF, Balk-Møller E, Rehfeld JF, Reimann F, Gribble FM, Holst JJ (2016) Peptide production and secretion in GLUTag, NCI-H716 and STC-1 cells: a comparison to native L-cells. J Mol Endocrinol 56:201–201CrossRefPubMedGoogle Scholar
  27. Kusuhara Y1, Yoshida R, Ohkuri T, Yasumatsu K, Voigt A, Hübner S, Maeda K, Boehm U, Meyerhof W, Ninomiya Y (2013) Taste responses in mice lacking taste receptor subunit T1R1. J Physiol 591:1967–1985CrossRefPubMedPubMedCentralGoogle Scholar
  28. Latorre R, Sternini C, De Giorgio R, Greenwood-Van Meerveld B (2016) Enteroendocrine cells: a review of their role in brain-gut communication. Neurogastroenterol Motil 2016(28):620–630CrossRefGoogle Scholar
  29. Li X, Staszewski L, Xu H, Durick K, Zoller M, Adler E (2002) Human receptors for sweet and umami taste. Proc Natl Acad Sci U S A 99:4692–4696CrossRefPubMedPubMedCentralGoogle Scholar
  30. Martins P, Fakhry J, Chaves de Oliveira E, Hunne B, Fothergill L, Ringuet M, d’Avila Reis D, Rehfeld JF, Callaghan B, Furness JB (2017) Analysis of enteroendocrine cell populations in the human colon. Cell Tissue Res 367:161–168CrossRefPubMedGoogle Scholar
  31. McCarthy T, Green BD, Calderwood D, Gillespier A, Cryan JF, Giblin L (2015) STC-1 cells Chapter 19. In: Verhoeckx K, Cotter P, Lopez-Exposito I, Kleiveland C, Lea T, Mackie A, Requena T, Swiatecka D, Wichers H (eds) The impact of food bioactives on health: in vitro and ex vivo models Cham (CH). Springer, Berlin, Heidleber New York, dio. CrossRefGoogle Scholar
  32. Nelsen G, Chandrashekar J, Hoon MA, Feng L, Zhao G, Ryba NJ, Zucker CS (2002) An amino-acid receptor. Nature 416:199–202CrossRefGoogle Scholar
  33. Oya M, Kitaguchi T, Pais R, Reimann F, Gribble F, Tsuboi T (2013) The G protein-coupled receptor family C group 6 subtype A (GPRC6A) receptor is involved in amino acid-induced glucagon-like peptide-1 secretion from GLUTag cells. J Biol Chem 288:4513–4521CrossRefPubMedGoogle Scholar
  34. Pais R, Gribble FM, Reimann F (2016) Signalling pathways involved in the detection of peptones by murine small intestinal enteroendocrine L-cells. Peptides 77:9–15CrossRefPubMedPubMedCentralGoogle Scholar
  35. Pal Choudhuri S, Delay RJ, Delay ER (2015) L-amino acids elicit diverse response patterns in taste sensory cells: a role for multiple receptors. PLoS One 10:e0130088CrossRefPubMedPubMedCentralGoogle Scholar
  36. Palmer RK (2018) A pharmacological perspective on the study of taste. Pharmacol Rev 71:20–48CrossRefGoogle Scholar
  37. Pi M, Nishimoto SK, Quarles LD (2017) CPRC6A: jack of all metabolism (or master of none). Molec Metab 6:185–193CrossRefGoogle Scholar
  38. Qian J, Mummalaneni SK, Alkahtani RM, Mahavadi S, Murthy KS, Grider JR, Lyall V (2016) Nicotine-induced effects on nicotinic acetylcholine receptors (nAChRs), Ca2+ and brain-derived neurotrophic factor (BDNF) in STC-1 cells. PLoS One 11:e0166565. CrossRefPubMedPubMedCentralGoogle Scholar
  39. Reimann F, Habib AM, Tolhurst G, Parker HE, Rogers GJ, Gribble FM (2008) Glucose sensing in L cells: a primary cell study. Cell Metab 8:532–539CrossRefPubMedPubMedCentralGoogle Scholar
  40. Rettenberger AT, Schulze W, Breer H, Haid D (2015) Analysis of the protein related receptor GPR92 in G-cells. Front Physiol 6:261.
  41. Reynaud Y, Fakhry J, Fothergill L, Callaghan B, Ringuet M, Hunne B, Bravo DM, Furness JB (2016) The chemical coding of 5-hydroxytryptamine containing enteroendocine cells in the mouse gastrointestinal tract. Cell Tissue Res 364:489–497CrossRefPubMedGoogle Scholar
  42. Roth KA, Hertz JM, Gordon JI (1990) Mapping enteroendocrine cell populations in transgenic mice reveals an unexpected degree of complexity in cellular differentiation within the gastrointestinal tract. J Cell Biol 110:1791–1801CrossRefPubMedGoogle Scholar
  43. San Gabriel A, Uneyama H (2013) Amino acid sensing in the gastrointestinal tract. Amino Acids 45:451–461CrossRefPubMedGoogle Scholar
  44. San Gabriel A, Uneyama H, Yoshie S, Torii K (2005) Cloning and characterization of a novel mGluR1 variant from vallate papillae that functions as a receptor for L-glutamate stimuli. Chem 30:i25–i26Google Scholar
  45. Sbarbati A, Bramanti P, Benati D, Merigo F (2010) The diffuse chemosensory system: exploring the iceberg toward the definition of functional roles. Prog Neurobiol 91:77–89CrossRefPubMedGoogle Scholar
  46. Schneider C, O’Leary CE, von Moltke J, Liang HE, Ang QY, Turnbaugh PJ, Radhakrishnan S, Pellizzon M, Ma A, Locksley RM (2018) A metabolite-triggered tuft cell-ILC2 circuit drives small intestinal remodeling. Cell 174:271–284CrossRefPubMedPubMedCentralGoogle Scholar
  47. Schütz B, Jurastow I, Bader S, Ringer C, von Engelhardt J, Chubanov V, Gudermann T, Diener M, Kummer W, Krasteva-Christ G, Weihe E (2015) Chemical coding and chemosensory properties of cholinergic brush cells in the mouse gastrointestinal and biliary tract. Front Physiol 6:87.
  48. Steensels S, Depoortere I (2018) Chemoreceptors in the gut. Annu Rev Physiol 80:117–141CrossRefPubMedGoogle Scholar
  49. Sutherland K, Young RL, Cooper NJ, Horowitz M, Blackshaw LA (2007) Phenotypic characterization of taste cells of the mouse small intestine. Am J Phys 292:G1420–G1428Google Scholar
  50. Symonds EL, Peiris M, Page AJ, Chia B, Dogra H, Masding A, Galanakis V, Atiba M, Bulmer D, Young RL, Blackshaw LA (2015) Mechanisms of activation of mouse and human enteroendocrine cells by nutrients. Gut 64:618–626CrossRefPubMedGoogle Scholar
  51. Wang JH, Inoue T, Higashiyama M, Guth PH, Engel E, Kaunitz JD, Akiba Y (2011) Umami receptor activation increases duodenal bicarbonate secretion via glucagon-like peptide-2 release in rats. J Pharmacol Exp Ther 339:464–473CrossRefPubMedPubMedCentralGoogle Scholar
  52. Wellendorph P, Brauner-Osborne H (2009) Molecular basis for amino acid sensing by family C G-protein-coupled receptors. Brit J Pharmacol 156:869–884CrossRefGoogle Scholar
  53. Wellendorph P, Johansen LD, Brauner-Osborne H (2009) Molecular pharmacology of promiscuous seven transmembrane receptors sensing organic nutrients. Molec Pharmacol 76:453–463CrossRefGoogle Scholar
  54. Yamaguchi S (1970) The synergistic taste effect of monosodium glutamate and disodium 5′-inosinate. J Food Sci 32:473–478CrossRefGoogle Scholar
  55. Yasumatsu K, Manabe T, Yoshida R, Iwatsuki K, Uneyama H, Takahe NY (2015) Involvement of multiple taste receptors in umami taste: analysis of gustatory nerve responses in metabotropic glutamate receptor 4 knockout mice. J Physiol 593(4):1021–1034CrossRefPubMedPubMedCentralGoogle Scholar
  56. Young RL, Sutherland K, Pezos N, Brierley SM, Horowitz M, Rayner CK, Blackshaw LA (2009) Expression of taste molecules in the upper gastrointestinal tract in humans with and without type 2 diabetes. Gut 58:337–346CrossRefPubMedGoogle Scholar
  57. Zhang F, Klebansky B, Fine RM, Xu H, Pronin A, Liu H, Tachdjian C, Li X (2008) Molecular mechanism for the umami taste synergism. Proc Natl Acad USA 105:20930–20934CrossRefGoogle Scholar
  58. Zhao GQ, Zhang Y, Hoon MA, Chandrashekar J, Erlenbach I, Ryba NJ, Zuker CS (2003) The receptors for mammalian sweet and umami taste. Cell 115:255–266CrossRefPubMedGoogle Scholar
  59. Zhou HR, Pestka JJ (2015) Deoxynivalenol (vomitoxin)-induced cholecystokinin and glucagon-like peptide-1 release in the STC-1 enteroendocrine cell model is mediated by calcium-sensing receptor and transient receptor potential ankyrin-1 channel. Toxicol Sci 145:407–417CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Physiology and Biophysics, VCU Program in Enteric Neuromuscular Sciences (VPENS)Virginia Commonwealth UniversityRichmondUSA

Personalised recommendations