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Updated: May 25, 2026
09:41
Measuring the Rate of Lipolysis in Ex Vivo Murine Adipose Tissue and Primary Preadipocytes Differentiated In Vitro
Published on: March 17, 2023
Integrin-dependent Akt1 activation regulates PGC-1 expression and fatty acid oxidation
Craig C Beeson1, Gyda C Beeson, Haley Buff
1Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, S.C., USA.
Journal of Vascular Research
|January 18, 2012
Summary
Short-fiber poly-N-acetyl glucosamine nanofibers (sNAG) enhance endothelial cell motility and metabolism by activating integrins. This process involves increased fatty acid oxidation, crucial for cell movement.
Area of Science:
- Biomaterials Science
- Cell Biology
- Integrative Physiology
Background:
- Marine diatom-derived poly-N-acetyl glucosamine nanofibers promote wound healing by activating integrins.
- Short-fiber poly-N-acetyl glucosamine nanofibers (sNAG) increase endothelial cell motility and metabolic rate without affecting proliferation.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying sNAG-induced endothelial cell responses.
- To investigate the role of integrin signaling and metabolic pathways in sNAG activity.
Main Methods:
- Seahorse Bioanalyzer for real-time oxygen consumption measurement.
- Western blotting for Akt1, PGC-1α, and PDK4 expression analysis.
- Inhibition studies using etomoxir and (3)H-palmitate uptake assays.
Main Results:
- sNAG treatment increased oxygen consumption rates, dependent on integrin activation of Akt1.
- Akt1 activation led to increased expression of PGC-1α and PDK4, suggesting fatty acid oxidation regulation.
- Inhibition of fatty acid oxidation blocked sNAG-induced oxygen consumption and cell motility, with PDK4 being essential.
Conclusions:
- A linear pathway exists where integrin-Akt1 activation by sNAG increases PGC-1α and PDK4 expression.
- This pathway enhances energy production through increased fatty acid oxidation, driving cell motility.
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