Larazotide 10mg

Description

Disclaimer: Larazotide is not approved by the U.S. Food and Drug Administration (FDA) for human or veterinary use. It is intended strictly for laboratory and research purposes only.

What is Larazotide?

Larazotide, also designated AT-1001, is a synthetic octapeptide derived from the zonula occludens toxin (ZOT) produced by Vibrio cholerae. Its amino acid sequence is H-Gly-Gly-Val-Leu-Val-Gln-Pro-Gly-OH. Larazotide was designed as a tight junction regulator and has been investigated in preclinical and cell-based research settings as a pharmacological tool for studying intestinal epithelial barrier integrity and paracellular permeability mechanisms.

Larazotide is proposed to act as a tight junction stabilizer by antagonizing the endogenous zonulin pathway, a physiological signaling cascade involved in the reversible regulation of intestinal tight junction opening. Research interest in Larazotide centers on its utility as a laboratory tool for studying paracellular permeability, claudin and occludin expression dynamics, and zonulin-mediated barrier disruption in intestinal epithelial cell models and preclinical gastrointestinal research systems.

Larazotide is not an approved therapeutic compound. It is intended exclusively for qualified researchers operating in controlled laboratory environments. It is not a dietary supplement or consumer product and has no approved indications for human or veterinary use.

PROPERTIES OF LARAZOTIDE

Property	Details
CAS Number	258818-34-7 (Larazotide free base) 881851-50-9 (Larazotide acetate salt)
Molar Mass	725.8 Da (free base, C₃₂H₅₅N₉O₁₀) ~785.9 Da (acetate salt form)
Chemical Formula	C₃₂H₅₅N₉O₁₀
Purity	≥98% (HPLC verified)
PubChem CID	9810532
Stability / Shelf Life	24 months when stored lyophilized at −20°C under recommended conditions
Synonyms	AT-1001; Larazotide acetate; INN Larazotide; ZOT-derived octapeptide tight junction regulator
Storage Instructions	−20°C (lyophilized); protect from light, heat, and moisture
Amino Acid Sequence	H-Gly-Gly-Val-Leu-Val-Gln-Pro-Gly-OH (GGVLVQPG)
IUPAC	2-[[(2S)-1-[(2S)-5-amino-2-[[(2S)-2-               [[(2S)-2-[[(2S)-2-[[2-[(2-aminoacetyl)               amino]acetyl]amino]-3-methylbutanoyl]               amino]-4-methylpentanoyl]amino]-3-               methylbutanoyl]amino]-5-oxopentanoyl]               pyrrolidine-2-carbonyl]amino]acetic acid
WADA Status	Not listed on the WADA 2026 Prohibited List

WORKING MECHANISM OF LARAZOTIDE

Larazotide is proposed to exert its observed activity in experimental models through antagonism of the zonulin signaling pathway, a physiological cascade that regulates reversible opening of intestinal epithelial tight junctions via modulation of the epidermal growth factor receptor (EGFR) and protease-activated receptor 2 (PAR2) signaling axis. Zonulin, the endogenous mediator in this system, initiates tight junction disassembly through downstream activation of phospholipase C, protein kinase C alpha (PKCα), and myosin light chain kinase (MLCK), leading to actin-myosin cytoskeletal reorganization and paracellular gap formation. Larazotide has been proposed to competitively interfere with zonulin receptor engagement at the epithelial surface, attenuating downstream tight junction disassembly in cell-based intestinal models.

Mechanistically, Larazotide is thought to influence:

• Attenuation of zonulin-induced tight junction opening in Caco-2 intestinal epithelial cell monolayer preparations, observed as preservation of transepithelial electrical resistance (TEER) in barrier permeability assays
• Modulation of claudin-1, claudin-2, and occludin expression dynamics in intestinal epithelial cell preparations under barrier disruption experimental conditions
• Inhibition of PKCα-mediated cytoskeletal reorganization downstream of zonulin receptor activation, proposed based on pathway mapping studies in cell culture systems
• Reduction of paracellular flux of marker molecules in in vitro intestinal permeability assay systems following exposure to barrier-disrupting stimuli
• Stabilization of tight junction protein complex assembly at the apical junctional complex in epithelial monolayer preparations under experimental challenge conditions

The precise molecular binding target of Larazotide at the epithelial surface has not been fully characterized in published literature. The compound is proposed to act as a luminal tight junction regulator with predominantly local activity in intestinal epithelial models. All mechanistic findings are derived from in vitro cell-based assays and preclinical animal models only. Human mechanistic data remain limited.

What are the Potential Research Observations of Larazotide?

The following research findings are based on articles retrieved from PubMed and are reported from preclinical and in vitro studies only. These findings do not constitute clinical evidence.

Intestinal Epithelial Barrier Integrity in Cell Monolayer Models:

Larazotide has been investigated as a pharmacological tool for studying tight junction regulation in intestinal epithelial cell preparations. In vitro studies using Caco-2 cell monolayers documented attenuation of barrier-disrupting stimuli, including inhibition of ZO-1 redistribution and actin rearrangement induced by gliadin fragments, with preservation of transepithelial electrical resistance under experimental challenge conditions. These observations have provided mechanistic data on the zonulin pathway in intestinal barrier research. Findings are from cell culture monolayer systems and do not reflect clinical intestinal physiology. [Gopalakrishnan et al., 2012]

Paracellular Permeability Modulation in Preclinical Intestinal Models:

Larazotide has been employed as a laboratory tool in preclinical intestinal models to investigate tight junction regulation under barrier-disrupting conditions. In cell-based preparations using Caco-2 and IEC6 intestinal epithelial cells, Larazotide exposure was associated with inhibition of paracellular flux of tracer molecules and reduced translocation of gliadin peptides across epithelial monolayers under experimental conditions. These findings contribute to characterizing the functional role of tight junction regulation in intestinal permeability research. Observations are from in vitro cell-based systems. [Gopalakrishnan et al., 2012]

Tight Junction Assembly Research:

Larazotide has been investigated for its capacity to promote de novo tight junction assembly in epithelial cell preparations. In calcium switch assay models using MDCK cells, Larazotide exposure was associated with facilitation of tight junction reassembly following calcium depletion-induced disruption, with observed improvements in barrier integrity markers under controlled experimental conditions. These observations contribute to understanding the bidirectional regulatory role of Larazotide as both an inhibitor of junction disassembly and a promoter of junction assembly in cell-based research models. Findings are from in vitro experimental systems only. [Gopalakrishnan et al., 2012]

Zonulin Pathway Characterization in Gliadin-Challenge Cell Models:

Larazotide has been investigated as a research tool in cell-based models examining the role of the zonulin pathway in gliadin-induced intestinal barrier disruption. In Caco-2 cell preparations exposed to gliadin peptides and cytokine stimuli, Larazotide exposure was associated with inhibition of tight junction protein redistribution and preservation of barrier function parameters, providing mechanistic data on zonulin pathway involvement in gliadin-triggered barrier disruption. Findings are from cell-based experimental systems. [Gopalakrishnan et al., 2012]

Note: Larazotide is not approved by the U.S. Food and Drug Administration (FDA) for human or veterinary use. It has no approved therapeutic indications. This compound is intended strictly for scientific research purposes only.

Safety Profile and Toxicological Considerations

Researchers have noted the following observations in experimental settings. Long-term safety data remain absent, and a complete toxicity profile has not been established in any biological system.

• No LD50 or standardized chronic toxicity data are available in the peer-reviewed preclinical literature for Larazotide
• No validated human pharmacokinetic or pharmacodynamic profile applicable to research use settings has been established
• Inadvertent laboratory exposure risks are not characterized; no occupational safety data exists for this compound
• As a short synthetic octapeptide, Larazotide is expected to be susceptible to proteolytic degradation in biological matrices, which must be accounted for in experimental design
• Off-target effects on epithelial tight junction regulation in non-intestinal tissue preparations cannot be excluded based on available data

WHY CHOOSE RCDBIO FOR LARAZOTIDE?

Each batch of Larazotide supplied by RCDbio undergoes independent third-party laboratory testing, with a batch-specific Certificate of Analysis (COA) available for researcher verification before experimental use.

• Independent third-party laboratory testing per batch
• COA confirming compound identity and purity per lot
• Purity verified by HPLC to ≥98%
• Molecular identity confirmed against CAS 881851-50-9
• RCDbio does not self-certify; all quality verification is conducted by accredited independent laboratories

Disclosure: Sponsored by RCDbio. This content is for informational purposes only and does not constitute an endorsement of any product for human use.

FREQUENTLY ASKED QUESTIONS

Is Larazotide approved for human use?

No. Larazotide is not approved by the FDA for any human or medical application. It is classified as a research-use peptide only and has no approved therapeutic indications in the United States or any other regulatory jurisdiction. It is intended exclusively for qualified researchers in controlled laboratory settings.

What is the structural origin of Larazotide, and how does it relate to the zonulin pathway?

Larazotide is an octapeptide derived from zonula occludens toxin (ZOT), a protein produced by Vibrio cholerae that modulates intestinal epithelial tight junctions through the zonulin receptor pathway. Larazotide was engineered from a functional domain of ZOT to act as a competitive antagonist of the endogenous zonulin signaling cascade. The compound’s proposed mechanism involves interference with zonulin receptor engagement at the intestinal epithelial surface, attenuating downstream tight junction disassembly in experimental models.

What molecular targets is Larazotide proposed to interact with in research models?

Based on published preclinical and cell-based research, Larazotide is proposed to antagonize the zonulin receptor pathway at the intestinal epithelial surface, interfering with downstream activation of PKCα and MLCK-mediated cytoskeletal reorganization. Associated signaling components investigated in research models include EGFR and PAR2 as proposed proximal receptor elements in the zonulin cascade. The precise binding target has not been definitively characterized, and mechanistic data are primarily from cell culture systems.

How should Larazotide be stored in a laboratory setting?

Lyophilized Larazotide should be stored at −20°C in a sealed, desiccated container protected from light, heat, and moisture. Reconstituted solutions should be stored at 4°C and used within 48 to 72 hours to maintain peptide integrity. Single-use aliquots are recommended before freezing to avoid repeated freeze-thaw cycles, which are associated with reduced peptide stability. Shelf life under recommended lyophilized storage conditions is reported at up to 24 months.

What experimental systems have been used in Larazotide research?

Published laboratory studies have primarily employed Caco-2 and IEC6 intestinal epithelial cell monolayer preparations for in vitro barrier permeability and TEER assays, along with MDCK cell calcium switch assay models for tight junction assembly studies. Gliadin-challenge cell culture models have been used in barrier disruption research. All findings relevant to laboratory research use are derived from preclinical and cell-based experimental systems.

REFERENCES

Gopalakrishnan, S., Tripathi, A., Tamiz, A. P., Alkan, S. S., & Pandey, N. B. (2012). Larazotide acetate promotes tight junction assembly in epithelial cells. Peptides, 35(1), 95–101. https://pubmed.ncbi.nlm.nih.gov/22401910/ 

Gopalakrishnan, S., Durai, M., Kitchens, K., Tamiz, A. P., Somerville, R., Ginski, M., Paterson, B. M., Murray, J. A., Verdu, E. F., Alkan, S. S., & Pandey, N. B. (2012). Larazotide acetate regulates epithelial tight junctions in vitro and in vivo. Peptides, 35(1), 86–94. https://pubmed.ncbi.nlm.nih.gov/22401908/ 

Disclaimer

Larazotide is exclusively for laboratory research purposes. RCDbio products are not intended to diagnose, prevent, treat, or cure any disease or medical condition. The Food and Drug Administration has not evaluated the statements on this page. Researchers must comply with all applicable local laws and regulations governing the use of research compounds. By purchasing, you agree to RCDbio Terms and Conditions. RCDbio reserves the right to refuse sales to unauthorized individuals.