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Published on: February 10, 2014
Larazotide acetate promotes tight junction assembly in epithelial cells
Shobha Gopalakrishnan1, Amit Tripathi, Amir P Tamiz
1Alba Therapeutics, 650 S. Exeter, Suite 1040, 10th floor, Baltimore, MD 21202, United States.
Peptides
|March 10, 2012
Summary
Larazotide acetate enhances tight junction (TJ) assembly and barrier function. This peptide promotes actin rearrangement and protein redistribution, improving intestinal epithelial cell integrity.
Area of Science:
- Epithelial biology
- Cellular biology
- Gastroenterology
Background:
- Tight junctions (TJ) are crucial for epithelial barrier function and cell polarity.
- Dysfunctional TJs are implicated in diseases like celiac and inflammatory bowel disease.
- TJ assembly involves E-cadherin, actin dynamics, and signaling pathways.
Purpose of the Study:
- To investigate the effect of larazotide acetate on de novo TJ assembly.
- To evaluate larazotide acetate's impact on TJ maturation and barrier function in intestinal epithelial models.
Main Methods:
- Utilized Madin-Darby canine kidney (MDCK) cells in a calcium switch assay.
- Employed Caco-2 cell models to assess TJ maturation and permeability.
- Analyzed actin rearrangement and the distribution of TJ/adherens junction (AJ) proteins.
Main Results:
- Larazotide acetate promoted TJ assembly and actin rearrangement in MDCK cells.
- Enhanced junctional localization of ZO-1, occludin, claudins, and E-cadherin was observed.
- Larazotide acetate improved TJ maturation and reduced paracellular permeability in leaky Caco-2 cells.
Conclusions:
- Larazotide acetate positively modulates TJ assembly and enhances epithelial barrier function.
- The peptide facilitates TJ formation by promoting actin dynamics and protein redistribution.
- Larazotide acetate shows potential for therapeutic applications in conditions with TJ dysfunction.
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