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Updated: Feb 21, 2026
09:59
Functional Reconstitution and Channel Activity Measurements of Purified Wildtype and Mutant CFTR Protein
Published on: March 9, 2015
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CFTR Influences Beta Cell Function and Insulin Secretion Through Non-Cell Autonomous Exocrine-Derived Factors
Xingshen Sun1, Yaling Yi1, Weiliang Xie1
1Anatomy and Cell Biology, University of Iowa, Iowa City, Iowa 52242.
Endocrinology
|October 5, 2017
Summary
Cystic fibrosis (CF) impairs islet insulin secretion through a paracrine mechanism, not directly via CFTR in beta cells. Proinflammatory factors from ductal cells influence insulin release in CF diabetes.
Area of Science:
- Endocrinology
- Cell Biology
- Genetics
Background:
- Cystic fibrosis (CF) is linked to beta-cell dysfunction and diabetes.
- The precise role of the cystic fibrosis transmembrane conductance regulator (CFTR) in islet insulin secretion is not fully understood.
Purpose of the Study:
- To investigate CFTR-dependent, islet-autonomous mechanisms influencing insulin secretion in cystic fibrosis.
- To elucidate the paracrine signaling pathways involved in CF-related diabetes.
Main Methods:
- Utilized islets from CFTR knockout ferrets and wild-type controls.
- Assessed insulin content, glucose-stimulated insulin secretion (GSIS), and intracellular calcium levels.
- Employed gene expression analysis and single-molecule fluorescent in situ hybridization (smFISH).
Main Results:
- CFTR knockout islets showed reduced insulin content and impaired GSIS.
- CF islets exhibited compensatory mechanisms in low glucose, including elevated SLC2A1 transcripts and altered ion channel activity.
- Higher IL-6 secretion in CF islets mimicked a CF-like phenotype in wild-type islets.
- CFTR RNA was localized in ductal cells, not endocrine beta cells, suggesting a paracrine role.
Conclusions:
- CFTR influences beta-cell function indirectly through paracrine signaling.
- Proinflammatory factors from islet-associated exocrine-derived cells mediate CFTR's effect on insulin secretion.
- Findings suggest a novel mechanism contributing to diabetes in cystic fibrosis.
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