Larazotide Acetate (AT-1001) Tight Junction Regulator CAS 881851-50-9

Larazotide Acetate (AT-1001) – Synthetic Octapeptide Tight Junction Regulator

Basic Information

• Product Name: Larazotide acetate (AT-1001)

• CAS Number: 881851-50-9

• Molecular Formula: C₃₄H₅₉N₉O₁₂

• Molecular Weight: 785.9 g/mol

• Purity: ≥98% (HPLC)

• Appearance: White to off-white powder

• Sequence: H-Gly-Gly-Val-Leu-Val-Gln-Pro-Gly-OH (GGVLVQPG)

• Solubility: Soluble in water

• Storage: Store at –20°C, protected from light and moisture

Overview
Larazotide acetate (also known as AT-1001) is a synthetic octapeptide derived from the zonula occludens toxin (Zot) of Vibrio cholerae. It functions as a tight junction regulator that reverses "leaky" intestinal epithelial junctions to their normally closed state. By acting as a zonulin antagonist, it reduces intestinal permeability and helps restore barrier function. Larazotide acetate is currently under investigation in Phase III clinical trials as an adjunctive therapy for celiac disease.

Applications

• Celiac disease research: Studied as a therapeutic agent to reduce gluten-induced intestinal permeability and inflammation.

• Inflammatory bowel disease (IBD): Investigated for its potential to restore gut barrier function.

• Intestinal barrier protection: Shown to protect epithelial integrity in models of anoxia/reoxygenation injury.

• Other disease models: Evaluated in collagen-induced arthritis and intestinal ischemic injury.

• Drug delivery: Explored as a permeability-regulating agent for oral peptide and protein delivery.

Mechanism of Action
Larazotide acetate exerts its effects through multiple pathways:

• Zonulin antagonism: Inhibits zonulin-induced increases in intestinal permeability.

• Tight junction stabilization: Promotes redistribution and rearrangement of tight junction proteins (e.g., occludin, claudins) and actin filaments.

• MLCK inhibition: Reduces myosin light chain kinase activity, decreasing tension on actin filaments and facilitating tight junction closure.

• Epithelial proliferation: Promotes epithelial cell proliferation and barrier integrity.

Key Properties

• Highly specific tight junction modulator.

• Orally bioavailable – suitable for oral administration.

• Selective inhibition of zonulin-mediated permeability without affecting other paracellular pathways.

• Well-tolerated in clinical trials with a favorable safety profile.

Handling and Storage

• Store at –20°C in tightly sealed containers, protected from light and moisture.

• For research use only; not for human therapeutic use.

• Use appropriate personal protective equipment (gloves, lab coat, safety goggles) when handling.

• Reconstitute in water or appropriate buffer as needed.

Packaging
Available in 1 g, 5 g, and bulk quantities upon request. Custom packaging available.

Quality Assurance
Each batch is tested for purity (by HPLC), peptide content, and identity (by mass spectrometry) to ensure consistent quality.