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Sustained Administration of β-cell Mitogens to Intact Mouse Islets Ex Vivo Using Biodegradable Poly(lactic-co-glycolic acid) Microspheres
Published on: November 5, 2016
Fibrin improves beta (INS-1) cell function, proliferation and survival through integrin αvβ3
Matthew Riopel1, William Stuart, Rennian Wang
1Children's Health Research Institute, 800 Commissioners Road East, London, Ontario N6C 2V5, Canada.
Acta Biomaterialia
|June 11, 2013
Summary
Fibrin, a provisional extracellular matrix protein, enhances beta cell function and proliferation. This occurs through integrin αvβ3 interactions, promoting islet-like cluster formation and insulin secretion.
Area of Science:
- * Stem cell biology
- * Cell signaling
- * Biomaterials science
Background:
- * Extracellular matrix (ECM) and integrin signaling influence beta cell function.
- * Beta cells lose function and senesce with prolonged culture on ECM proteins.
- * Fibrin, a provisional ECM protein, may maintain beta cell function, but mechanisms are unclear.
Purpose of the Study:
- * To investigate how fibrin interacts with integrin receptors.
- * To determine fibrin's role in beta cell cluster formation, proliferation, and function.
Main Methods:
- * Cultured rat insulinoma (INS-1) cells on polystyrene or 2-D/3-D fibrin gels for up to 4 weeks.
- * Utilized scanning electron microscopy to observe cell-fibrin interactions.
- * Measured glucose-stimulated insulin secretion, integrin expression, and levels of phosphorylated FAK, Erk1/2, and Akt.
- * Assessed cell proliferation, apoptosis, and the effects of integrin αvβ3 blockade.
Main Results:
- * Fibrin culture promoted islet-like cluster formation and direct cell-fibrin contact.
- * Fibrin-cultured cells exhibited significantly increased glucose-stimulated insulin secretion.
- * Increased integrin αvβ3, phosphorylated FAK, Erk1/2, and Akt were observed.
- * Cell proliferation increased, while apoptosis decreased in fibrin-cultured cells.
- * Integrin αvβ3 blockade impaired cell spreading, reduced FAK phosphorylation, and increased apoptosis.
Conclusions:
- * Fibrin promotes beta cell function, proliferation, and survival.
- * Integrin αvβ3 signaling is crucial for fibrin's effects on beta cells.
- * Fibrin represents a promising biomaterial for supporting beta cell function.
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