Evidence map›Paper›PMID 42496592›Full record

ArticleDiabetes2026

GIP Acutely Blunts Insulin- and GLP-1-Induced Muscle Microvascular Perfusion.

Jia Liu, Changzoon Chun, Thomas K Sin, Fang Zhao, Kevin W Aylor, Nusrat J Tushi, Shengyi Sun, Zhenqi Liu

Abstract read
In one paragraph

Article in Diabetes, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Jia LiuDivision of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA.
Changzoon ChunDepartment of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA.
Thomas K SinDivision of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA.
Fang ZhaoDivision of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA.
Kevin W AylorDivision of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA.
Nusrat J TushiDepartment of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA.
Shengyi SunDepartment of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA.
Zhenqi LiuDivision of Endocrinology and Metabolism, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA.ORCID 0000-0001-5077-0941

Funding

Role of Microvascular insulin resistance and cardiorespiratory fitness in diabetesR01DK124344 · NIDDK · UNIVERSITY OF COLORADO DENVER · PI ZHENQI LIU, JUDITH G. REGENSTEINER · 2021 to 2026
$3.5M
Effects of Exercise and GLP-1R Agonism on Muscle Microvascular Perfusion and Insulin ActionR01DK125330 · NIDDK · UNIVERSITY OF VIRGINIA · PI LIU, ZHENQI · 2020 to 2025
$3.3M
Novel role of endoplasmic reticulum-associated degradation in iron metabolismR01DK128077 · NIDDK · WAYNE STATE UNIVERSITY · PI Shengyi Sun · 2022 to 2026
$1.9M
Mechanisms Underlying the Pathogenesis of SEL1L-HRD1 ERAD Disease VariantsR01NS138119 · NINDS · UNIVERSITY OF VIRGINIA · PI Ling Qi, Shengyi Sun · 2025 to 2026
$1.3M
Novel Mechanism underlying fibrinogen biogenesis in the endoplasmic reticulumR01DK132068 · NIDDK · WAYNE STATE UNIVERSITY · PI SUN, SHENGYI · 2022 to 2024
$1.2M
Impact of obesity on microvascular insulin action and cardiorespiratory fitness in Type 1 DiabetesR01DK141617 · NIDDK · UNIVERSITY OF VIRGINIA · PI ZHENQI LIU · 2026 to 2026
$782k
Bioinformatics Core RRIDBioinformatics Core SCR 012718NIDDK NIH HHS R01 DK124344NIDDK NIH HHS R01 DK125330NIDDK NIH HHS R01 DK128077NIDDK NIH HHS R01DK128077NIDDK NIH HHS R01 DK132068NIDDK NIH HHS R01DK132068NIDDK NIH HHS R01 DK141617NIH HHS R01DK124344NIH HHS R01DK125330NIH HHS R01DK128077NIH HHS R01DK132068NIH HHS R01DK141617NIH HHS R01NS138119NINDS NIH HHS R01 NS138119NINDS NIH HHS R01NS138119University of Virginia
6 · The paper itself

Abstract

Glucose-dependent insulinotropic polypeptide (GIP) promotes nutrient storage, but its vascular actions in skeletal muscle remain unclear. To determine whether GIP regulates muscle microvascular perfusion, a key determinant of substrate use, we examined GIP receptor (GIPR) expression in vascular endothelium and assessed GIP effects in vivo in chow-fed and high-fat diet (HFD)-fed rats. Overnight-fasted rats received 120-min infusions of saline or GIP, with or without concurrent insulin or glucagon-like peptide 1 (GLP-1). Immunofluorescence microscopy demonstrated clear GIPR expression in conduit, resistance, and microvascular vessel endothelium. GIP alone did not alter muscle microvascular perfusion in either group but completely abolished insulin- and GLP-1-induced microvascular recruitment. In cultured endothelial cells, GIP dose-dependently increased endothelin-1 (ET-1) secretion and suppressed insulin- or GLP-1-stimulated nitric oxide production. Transcriptomic profiling implicated activation of the GIP-angiotensin II type 1 receptor-ET-1 pathway. In conclusion, GIPR is widely expressed in vascular endothelium. While GIP does not independently recruit muscle microvasculature, it antagonizes insulin- and GLP-1-mediated vasodilation, identifying GIP as a conditional regulator of skeletal muscle perfusion and nutrient delivery, consistent with its physiological effect in directing nutrients toward storage depots. ARTICLE HIGHLIGHTS: Skeletal muscle microvasculature is essential for nutrient delivery and metabolic regulation, but the vascular actions of glucose-dependent insulinotropic polypeptide (GIP) in muscle are unknown. We investigated whether GIP regulates skeletal muscle microvascular perfusion and interacts with insulin and GLP-1 signaling. GIP receptors are expressed in vascular endothelium, yet GIP alone does not increase muscle perfusion and instead antagonizes insulin- and GLP-1-mediated microvascular recruitment via possibly angiotensin II type 1 receptor-dependent endothelin-1/nitric oxide imbalance. GIP acts as a conditional regulator of skeletal muscle microvascular perfusion, revealing a novel mechanism of tissue-specific incretin regulation of nutrient partitioning.

Indexed as

Gastric Inhibitory PolypeptideGlucagon-Like Peptide 1InsulinMicrovesselsMuscle, SkeletalAnimalsDiet, High-FatEndothelin-1Endothelium, VascularMaleRatsRats, Sprague-DawleyReceptors, Gastrointestinal HormoneEndothelin-1Gastric Inhibitory Polypeptidegastric inhibitory polypeptide receptorGlucagon-Like Peptide 1InsulinReceptors, Gastrointestinal Hormone

Identifiers

PMID42496592
PMCPMC13728761

What OpenQuestion holds

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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.