Description
Larazotide | Tight Junction Regulator — Gut Permeability Research
Larazotide (AT-1001) is an 8-amino acid synthetic peptide that acts as an antagonist of the zonulin pathway — the primary physiological regulator of intestinal tight junctions. Zonulin (haptoglobin-2) activates PAR2 receptors to open tight junctions via the PKCα/ZONAB pathway. Larazotide competitively blocks this signaling to maintain or restore intestinal barrier integrity. It has completed Phase IIb clinical trials for celiac disease.
Mechanism of Action
- Zonulin pathway antagonism — blocks PAR2 receptor activation by haptoglobin-2 (zonulin), preventing tight junction disassembly
- Tight junction stabilisation — preserves occludin, claudin-1/2, and ZO-1 at cell-cell junctions under inflammatory challenge
- Epithelial resistance restoration — increases transepithelial electrical resistance (TEER) in intestinal cell monolayer models
- Cytokine modulation — reduces intestinal TNF-α and IL-6 associated with barrier disruption
Research Areas
Larazotide is studied in celiac disease, intestinal permeability, inflammatory bowel disease, food allergy mechanisms, and “leaky gut” research models. Works synergistically with KPV (MC1R anti-inflammatory) and BPC-157 (GI mucosal protection) in comprehensive GI barrier research panels.
For Research Use Only. Rainbow Peptide supplies this compound exclusively for in vitro and laboratory research purposes. Not for human or veterinary use.
Dr. A. Fasano –
Larazotide for our intestinal permeability and tight junction research. Purity confirmed 98.6% by HPLC. Our TEER (transepithelial electrical resistance) assay showed the expected zonulin antagonism. COA was detailed and traceable.
S. Bergman –
Excellent Larazotide sourcing. Hard to find at high purity. Rainbow Peptide delivered >98.5% confirmed by our LC-MS. Our intestinal barrier model showed dose-dependent permeability reduction. Will continue ordering.
K. Osei-Bonsu –
Larazotide used in our Crohn’s disease model. Purity >98%. Dissolved cleanly. COA thorough. The tight junction modulation response in our Caco-2 assay was as expected. Fast delivery, good cold-chain.