ArticleAmerican journal of physiology. Gastrointestinal and liver physiology2015
Glucose-dependent insulinotropic polypeptide-mediated signaling pathways enhance apical PepT1 expression in intestinal epithelial cells.
Article in American journal of physiology. Gastrointestinal and liver physiology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
9 citing papers in PubMed, 22 citations in OpenAlex.
- Chronic, but not acute, treatment with GLP-2 and GIP in combination increases glucose absorption in the isolated vascularly perfused rat intestine.Physiological reports · 2026Article
- Glucose-dependent insulinotropic polypeptide stimulates post-absorptive lipid secretion in the intestine.Frontiers in physiology · 2025Article
- Article
- Crosstalk Within the Intestinal Epithelium: Aspects of Intestinal Absorption, Homeostasis, and Immunity.Biomedicines · 2024Review
- Enteroendocrine cells regulate intestinal homeostasis and epithelial function.Molecular and cellular endocrinology · 2024Review
- Applications of Enteroendocrine Cells (EECs) Hormone: Applicability on Feed Intake and Nutrient Absorption in Chickens.Animals : an open access journal from MDPI · 2023Review
- Intracellular cAMP Sensor EPAC: Physiology, Pathophysiology, and Therapeutics Development.Physiological reviews · 2018Review
- Functional intercalated nanocomposites with chitosan-glutathione-glycylsarcosine and layered double hydroxides for topical ocular drug delivery.International journal of nanomedicine · 2018Article
- Slc15a1 is involved in the transport of synthetic F5-peptide into the seminiferous epithelium in adult rat testes.Scientific reports · 2015Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 3 institutions in 1 country.
Funding
Abstract
We have shown recently that glucose-dependent insulinotropic polypeptide (GIP), but not glucagon-like peptide 1 (GLP-1) augments H(+) peptide cotransporter (PepT1)-mediated peptide absorption in murine jejunum. While we observed that inhibiting cAMP production decreased this augmentation of PepT1 activity by GIP, it was unclear whether PKA and/or other regulators of cAMP signaling pathway(s) were involved. This study utilized tritiated glycyl-sarcosine [(3)H-glycyl-sarcosine (Gly-Sar), a relatively nonhydrolyzable dipeptide] uptake to measure PepT1 activity in CDX2-transfected IEC-6 (IEC-6/CDX2) cells, an absorptive intestinal epithelial cell model. Similar to our earlier observations with mouse jejunum, GIP but not GLP-1 augmented Gly-Sar uptake (control vs. +GIP: 154 ± 22 vs. 454 ± 39 pmol/mg protein; P < 0.001) in IEC-6/CDX2 cells. Rp-cAMP (a PKA inhibitor) and wortmannin [phosophoinositide-3-kinase (PI3K) inhibitor] pretreatment completely blocked, whereas neither calphostin C (a potent PKC inhibitor) nor BAPTA (an intracellular Ca(2+) chelator) pretreatment affected the GIP-augmented Gly-Sar uptake in IEC-6/CDX2 cells. The downstream metabolites Epac (control vs. Epac agonist: 287 ± 22 vs. 711 ± 80 pmol/mg protein) and AKT (control vs. AKT inhibitor: 720 ± 50 vs. 75 ± 19 pmol/mg protein) were shown to be involved in GIP-augmented PepT1 activity as well. Western blot analyses revealed that both GIP and Epac agonist pretreatment enhance the PepT1 expression on the apical membranes, which is completely blocked by wortmannin in IEC-6/CDX2 cells. These observations demonstrate that both cAMP and PI3K signaling pathways augment GIP-induced peptide uptake through Epac and AKT-mediated pathways in intestinal epithelial cells, respectively. In addition, these observations also indicate that both Epac and AKT-mediated signaling pathways increase apical membrane expression of PepT1 in intestinal absorptive epithelial cells.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.