Reciprocal regulation of the primary sodium absorptive pathways in rat intestinal epithelial cells
Open accessAbstract
Sodium absorption in the mammalian small intestine occurs predominantly by two primary pathways that include Na/H exchange (NHE3) and Na-glucose cotransport (SGLT1) on the brush border membrane (BBM) of villus cells. However, whether NHE3 and SGLT1 function together to regulate intestinal sodium absorption is unknown. Nontransformed small intestinal epithelial cells (IEC-18) were transfected with either NHE3 or SGLT1 small interfering RNAs (siRNAs) and were grown in confluent monolayers on transwell plates to measure the effects on Na absorption. Uptake studies were performed as well as molecular studies to determine the effects on NHE3 and SGLT1 activity. When IEC-18 monolayers were transfected with silencing NHE3 RNA, the cells demonstrated decreased NHE3 activity as well as decreased NHE3 mRNA and protein. However, in NHE3 siRNA-transected cells, SGLT1 activity, mRNA, and protein in the BBM were significantly increased. Thus, inhibition of NHE3 expression regulates the expression and function of SGLT1 in the BBM of intestinal epithelial cells. In addition, IEC-18 cells transected with silencing SGLT1 RNA demonstrated an inhibition of Na-dependent glucose uptake and a decrease in SGLT1 activity, mRNA, and protein levels. However, in these cells, Na/H exchange activity was significantly increased. Furthermore, NHE3 mRNA and protein levels were also increased. Therefore, the inhibition of SGLT1 expression stimulates the transcription and function of NHE3 and vice versa in the BBM of intestinal epithelial cells. Thus this study demonstrates that the major sodium absorptive pathways together function to regulate sodium absorption in epithelial cells.
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NHE3 and SGLT1 have been shown to regulate one another in mammalian intestinal epithelial cell models, including rabbit and rat cells.
“The two primary Na-absorptive pathways were previously shown to compensatorily regulate each other in rabbit and rat intestinal epithelial cells.”
From Regulation of Enterocyte Brush Border Membrane Primary Na-Absorptive Transporters in Human Intestinal Organoid-Derived Monolayers (2024) · cites this paper as [27]
The Results and Discussion report reciprocal, compensatory regulation of NHE3 and SGLT1 in rat IEC-18 intestinal epithelial cells. The Discussion mentions rabbit small-intestine studies only as suggesting an indirect link between the pathways, not as showing the reciprocal regulation claimed for rabbit cells. The rabbit portion is therefore unsupported by this source. (LLM, conf=0.88)
Experimental — accuracy not yet measuredThe reciprocal regulation between NHE3 and SGLT1 in human enterocytes is consistent with compensatory regulation observed in mammalian intestinal cell models.
“This is consistent with the compensatory regulation between NHE3 and SGLT1 observed in mammalian intestinal cell models [24,25,27], and therefore serves as proof of concept for using siRNA technology in patient-derived organoid monolayers.”
From Regulation of Enterocyte Brush Border Membrane Primary Na-Absorptive Transporters in Human Intestinal Organoid-Derived Monolayers (2024) · cites this paper as [27]
Reciprocal regulation between NHE3 and SGLT1 was previously demonstrated in a rat intestinal epithelial cell line (IEC-18).
“Reciprocal regulation between NHE3 and SGLT1 was previously demonstrated in a rat intestinal epithelial cell line (IEC-18) [27].”
From Regulation of Enterocyte Brush Border Membrane Primary Na-Absorptive Transporters in Human Intestinal Organoid-Derived Monolayers (2024) · cites this paper as [27]
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- [1]1. Anderson CM, Mendoza ME, Kennedy DJ, Raldua D, Thwaites DT. Inhibition of intestinal dipeptide transport by the neuropeptide VIP is an anti-absorptive effect via the VPAC1 receptor in a human enterocyte-like cell line (Caco-2). Br J Pharmacol 138: 564–573, 2003 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [2]2. Anderson CM, Thwaites DT. Regulation of intestinal hPepT1 (SLC15A1) activity by phosphodiesterase inhibitors is via inhibition of NHE3 (SLC9A3). Biochim Biophys Acta 1768: 1822–1829, 2007 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [3]3. Ausubel FM, Brent R, Kingston RE, Moore DD, Seidman JG, Smith JA, Stuhl K. Current Protocols in Molecular Biology. New York: Wiley, 1995 [Google Scholar]
- [4]4. Coon S, Kim J, Shao G, Sundaram U. Na-glucose and Na-neutral amino acid cotransport are uniquely regulated by constitutive nitric oxide in rabbit small intestinal villus cells. Am J Physiol Gastrointest Liver Physiol 289: G1030–G1035, 2005 [DOI] [PubMed] [Google Scholar]
- [5]5. Coon S, Shao G, Wisel S, Vulaupalli R, Sundaram U. Mechanism of regulation of rabbit intestinal villus cell brush border membrane Na/H exchange by nitric oxide. Am J Physiol Gastrointest Liver Physiol 292: G475–G481, 2007 [DOI] [PubMed] [Google Scholar]
- [6]6. Di Iorio E, Barbaro V, Ferrari S, Ortolani C, De Luca M, Pellegrini G. Q-FIHC: quantification of fluorescence immunohistochemistry to analyse p63 isoforms and cell cycle phases in human limbal stem cells. Microsc Res Tech 69: 983–991, 2006 [DOI] [PubMed] [Google Scholar]
- [7]7. Furukawa O, Luke CB, Guth PH, Engel E, Hirokawa M, Kaunitz JD. NHE3 inhibition activates duodenal bicarbonate secretion in the rat. Am J Physiol Gastrointest Liver Physiol 286: G102–G109, 2004 [DOI] [PubMed] [Google Scholar]
- [8]8. Gawenis LR, Franklin CL, Simpson JE, Palmer BA, Walker NM, Wiggins TM, Clark LL. cAMP inhibition of murine intestinal Na+/H+ exchange requires CFTR-mediated cell shrinkage of villus epithelium. Gastroenterology 125: 1148–1163, 2003 [DOI] [PubMed] [Google Scholar]
- [9]9. Gawenis LR, Stien X, Shull GE, Schultheis PJ, Woo AL, Walker NM, Clarke LL. Intestinal NaCl transport in NHE2 and NHE3 knockout mice. Am J Physiol Gastrointest Liver Physiol 282: G776–G784, 2002 [DOI] [PubMed] [Google Scholar]
- [10]10. Greeley T, Shumaker H, Wang Z, Schweinfest CW, Soleimani M. Downregulated in adenoma and putative anion transporter are regulated by CFTR in cultured pancreatic duct cells. Am J Physiol Gastrointest Liver Physiol 281: G1301–G1308, 2001 [DOI] [PubMed] [Google Scholar]
- [11]11. Kennedy DJ, Leibach FH, Ganapathy V, Thwaites DT. Optimal absorptive transport of the dipeptide glycylsarcosine is dependent on functional Na+/H+ exchange activity. Pflügers Arch 445: 139–146, 2002 [DOI] [PubMed] [Google Scholar]
- [12]12. Kennedy DJ, Raldua D, Thwaites DT. Dual modes of 5-(N-ethyl-N-isopropyl)amiloride modulation of apical dipeptide uptake in the human small intestinal epithelial cell line Caco-2. Cell Mol Life Sci 62: 1621–1631, 2005 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [13]13. Kiela PR, Ghishan FK. Na+-H+ exchange in the mammalian digestive tract. In: Physiology of the Gastrointestinal Tract (4th ed.) New York: Elseiver, 2006, p. 1847–1880 [Google Scholar]
- [14]14. Kiela PR, Xu H, Ghishan FK. Apical Na+/H+ exchangers in the mammalian gastrointestinal tract. J Physiol Pharmacol 57, Suppl 7: 51–79, 2006 [PubMed] [Google Scholar]
- [15]15. Ko SB, Shcheynikov N, Choi JY, Luo X, Ishibashi K, Thomas PJ, Kim JY, Kim KH, Lee MG, Naruse S, Muallem S. A molecular mechanism for aberrant CFTR-dependent HCO(3)(-) transport in cystic fibrosis. EMBO J 21: 5662–5672, 2002 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [16]16. Ko SB, Zeng W, Dorwart MR, Luo X, Kim KH, Millen L, Goto H, Naruse S, Soyombo A, Thomas PJ, Muallem S. Gating of CFTR by the STAS domain of SLC26 transporters. Nat Cell Biol 6: 343–350, 2004 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [17]17. Lamprecht G, Heil A, Baisch S, Lin-Wu E, Yun CC, Kalbacher H, Gregor M, Seidler U. The down regulated in adenoma (dra) gene product binds to the second PDZ domain of the NHE3 kinase A regulatory protein (E3KARP), potentially linking intestinal Cl−/HCO3− exchange to Na+/H+ exchange. Biochemistry 41: 12336–12342, 2002 [DOI] [PubMed] [Google Scholar]
- [18]18. Melvin JE, Park K, Richardson L, Schultheis PJ, Shull GE. Mouse down-regulated in adenoma (DRA) is an intestinal Cl(−)/HCO(3)(−) exchanger and is up-regulated in colon of mice lacking the NHE3 Na(+)/H(+) exchanger. J Biol Chem 274: 22855–22861, 1999 [DOI] [PubMed] [Google Scholar]
- [19]19. Orlov SN, Mongin AA. Salt-sensing mechanisms in blood pressure regulation and hypertention. Am J Physiol Heart Circ Physiol 293: H2039–H2053, 2007 [DOI] [PubMed] [Google Scholar]
- [20]20. Schweinfest CW, Spyropoulos DD, Henderson KW, Kim JH, Chapman JM, Barone S, Worrell RT, Wang Z, Soleimani M. slc26a3 (dra)-deficient mice display chloride-losing diarrhea, enhanced colonic proliferation, and distinct up-regulation of ion transporters in the colon. J Biol Chem 281: 37962–37971, 2006 [DOI] [PubMed] [Google Scholar]
- [21]21. Seidler U, Lenzen H, Cinar A, Tessema T, Bleich A, Riederer B. Molecular mechanisms of disturbed electrolyte transport in intestinal inflammation. Ann NY Acad Sci 1072: 262–275, 2006 [DOI] [PubMed] [Google Scholar]
- [22]22. Sundaram U, Knickelbein RG, Dobbins JW. Mechanism of intestinal secretion. Effect of serotonin on rabbit ileal crypt and villus cells. J Clin Invest 87: 743–746, 1991 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [23]23. Sundaram U, Knickelbein RG, Dobbins JW. pH regulation in ileum: Na(+)-H+ and Cl(−)-HCO3− exchange in isolated crypt and villus cells. Am J Physiol Gastrointest Liver Physiol 260: G440–G449, 1991 [DOI] [PubMed] [Google Scholar]
- [24]24. Sundaram U, Wisel S, Rajendren VM, West AB. Mechanism of inhibition of Na+-glucose cotransport in the chronically inflamed rabbit ileum. Am J Physiol Gastrointest Liver Physiol 273: G913–G919, 1997 [DOI] [PubMed] [Google Scholar]
- [25]25. Talukder JR, Kekuda R, Saha P, Sundaram U. Mechanism of leukotriene D4 inhibition of Na-alanine cotransport in intestinal epithelial cells. Am J Physiol Gastrointest Liver Physiol 295: G1–G6, 2008 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [26]26. Thiagarajah JR, Verkman AS. Water transport in the gastrointestinal tract. In: Physiology of the Gastrointestinal Tract (4th ed.). New York: Elsevier, 2006, p. 877–894 [Google Scholar]
- [27]27. Thwaites DT, Ford D, Glanville M, Simmons NL. H+/solute induced intracellular acidification leads to selective activation of apical Na+/H+ exchange in human intestinal epithelial cells. J Clin Invest 104: 629–635, 1999 [DOI] [PMC free article] [PubMed] [Google Scholar]
- [28]28. Thwaites DT, Kennedy DJ, Raldua D, Anderson CM, Mendoza ME, Bladen CL, Simmons NL. H/dipeptide absorption across the human intestinal epithelium is controlled indirectly via a functional Na/H exchanger. Gastroenterology 122: 1322–1333, 2002 [DOI] [PubMed] [Google Scholar]
- [29]29. Turner JR, Black ED. NHE3-dependent cytoplasmic alkalinization is triggered by Na+-glucose cotransport in intestinal epithelia. Am J Physiol Cell Physiol 281: C1533–C1541, 2001 [DOI] [PubMed] [Google Scholar]
- [30]30. Wheat VJ, Shumaker H, Burnham C, Shull GE, Yankaskas JR, Soleimani M. CFTR induces the expression of DRA along with Cl−/HCO3− exchange activity in tracheal epithelial cells. Am J Physiol Cell Physiol 279: C62–C71, 2000 [DOI] [PubMed] [Google Scholar]
- [31]31. Wright EM, Hirayama B, Loo D, Turk E, Hager K. Intestinal sugar transport. In: Physiology of the Gastrointestinal Tract. New York: Raven, 1994, p. 1751–1772 [Google Scholar]
- [32]32. Wright EM, Hirayama BA, Loo DF. Active sugar transport in health and disease. J Intern Med 261: 32–43, 2007 [DOI] [PubMed] [Google Scholar]
- [33]33. Wright EM, Loo D, Hirayama B, Turk E. Sugar absorption. In: Physiology of the Gastrointestinal Tract (4th ed.). New York: Elsevier, 2006, p. 1653–1666 [Google Scholar]
- [34]34. Wright EM, Loo DD, Hirayama BA, Turk E. Surprising versatility of Na+-glucose cotransporters: SLC5. Physiology (Bethesda) 19: 370–376, 2004 [DOI] [PubMed] [Google Scholar]
- [35]35. Yun CH, Tse CM, Nath SK, Levine SA, Brant SR, Donowitz M. Mammalian Na+/H+ exchanger gene family: structure and function studies. Am J Physiol Gastrointest Liver Physiol 269: G1–G11, 1995 [DOI] [PubMed] [Google Scholar] Articles from American Journal of Physiology - Cell Physiology are provided here courtesy of American Physiological Society
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Haynes, J., Palaniappan, B., Crutchley, J. M., & Sundaram, U. (2024) · Cells · doi:10.3390/cells13191623 · Cited by 2 · see citing works
“Reciprocal regulation between NHE3 and SGLT1 was previously demonstrated in a rat intestinal epithelial cell line (IEC-18) [27].”
BackgroundResultInfluentialSelf-citation
- Authors
- Coon, S., Kekuda, R., Saha, P., & Sundaram, U.
- Affiliations
- West Virginia University (US)
- Corresponding author
- Sundaram, Uma
- Venue
- American Journal of Physiology-Cell Physiology
- Publisher
- American Physiological Society
- Published
- 2011-03
- Volume
- 300
- Issue
- 3
- Pages
- C496-C505
- ISSN
- 0363-6143 (ISSN-L)
- 1522-1563
- PMC
- PMC3063980
- OpenAlex
- W2157476765
- Cited by
- 28
- References
- 0
- Citations by year
- 2025: 1 · 2024: 2 · 2023: 1 · 2022: 3 · 2021: 1 · 2020: 3 · 2019: 3 · 2018: 4 · 2017: 1 · 2016: 2 · 2015: 4 · 2012: 1
- FWCI
- 0.39
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- American Journal of Physiology-Cell Physiology (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Institutes of Health (5r29dk045062-06)
- National Institute of Diabetes and Digestive and Kidney Diseases (DK-45062, R01DK058034, DK 58034)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Ion Transport and Channel Regulation
- Health Sciences › Medicine › Oncology › Drug Transport and Resistance Mechanisms
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Digestive system and related health
- Keywords
- intestinal sodium absorption, Na+/H+ exchange, NHE3, SGLT1, Na+/glucose cotransport, brush border membrane, reciprocal regulation, small intestinal epithelial cells, IEC-18 cells, gene silencing
- MeSH terms
- Sodium-Hydrogen Exchanger 3, Animals, Cell Line, Intestinal Absorption, Intestinal Mucosa, Microvilli, RNA, Messenger, Sodium, Transcription, Genetic, Signal Transduction, Down-Regulation, Sodium-Hydrogen Exchangers, Feedback, Physiological, RNA, Small Interfering, Sodium-Glucose Transporter 1, Rats, Gene Knockdown Techniques
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