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Caveolin-1 Modulates Islet Amyloid Polypeptide Expression Through Interaction with TXNIP in Murine Pancreatic β-Cells
Kunying Liu1,2, Xubin Yang1,2,3,4, Shuo Lin1,2,3,4
1Department of Endocrinology & Metabolism, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China.
Biomedicines
|June 26, 2026
Summary
Caveolin-1 (Cav-1) is crucial for islet amyloid polypeptide (IAPP) secretion and expression in beta cells. Targeting the Cav-1-TXNIP interaction may help mitigate type 2 diabetes-related beta-cell dysfunction.
Area of Science:
- Cell Biology
- Endocrinology
- Molecular Biology
Background:
- Pathological islet amyloid polypeptide (IAPP) aggregation impairs beta-cell function in type 2 diabetes.
- Caveolin-1 (Cav-1) deficiency confers protection against palmitate-induced beta-cell apoptosis.
- Previous findings suggest Cav-1 influences IAPP expression.
Purpose of the Study:
- To investigate the impact of Cav-1 depletion on IAPP secretion and expression.
- To explore the role of thioredoxin-interacting protein (TXNIP) in Cav-1's regulation of IAPP.
- To identify potential therapeutic targets for IAPP-related beta-cell dysfunction.
Main Methods:
- Cav-1 knockdown using lentiviral vectors in NIT-1 cells and murine islets.
- Generation of an inducible beta-cell-specific Cav-1 knockout (iβ-Cav1 KO) mouse model.
- Assessment of IAPP levels, processing enzymes, degradation factors, and Cav-1/TXNIP interactions via ELISA, Western blot, qPCR, immunofluorescence, and co-immunoprecipitation.
Main Results:
- Cav-1 depletion significantly reduced IAPP secretion and expression both in vitro and in vivo.
- Iβ-Cav1 KO mice on a high-fat diet showed the lowest serum IAPP levels.
- Cav-1 depletion altered the expression of IAPP processing enzymes and degradation factors, and decreased TXNIP expression, revealing a physical interaction between Cav-1 and TXNIP.
Conclusions:
- Caveolin-1 is essential for regulating IAPP secretion and expression in beta cells.
- The physical interaction between Cav-1 and TXNIP suggests TXNIP mediates Cav-1's regulatory effects on IAPP.
- The Cav-1-TXNIP axis represents a potential therapeutic target for beta-cell dysfunction in type 2 diabetes.
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