Overview
B7-33 is a single-chain relaxin-family peptide analog designed to selectively activate the RXFP1 receptor. It is primarily of interest in the scientific community for its potential applications in receptor biology research, specifically focusing on GPCR signaling and cytoprotective mechanisms. Despite its promising preclinical results, B7-33 is currently not approved for clinical use and is available exclusively for research purposes. Its regulatory status as a research-only peptide means it is not accessible for therapeutic use in any medical setting.
The peptide has gained attention due to its ability to replicate some of the vasoprotective functions of human relaxin-2, a hormone with known cardioprotective and antifibrotic properties. However, B7-33 remains in the early stages of research, and its use is confined to laboratory settings. Researchers are particularly interested in its potential to reduce fibrotic encapsulation in implantable medical devices and its effects on cardiac remodeling post-myocardial infarction.
How It Works (Mechanism of Action)
B7-33 operates by activating the RXFP1 receptor, which is part of the relaxin family peptide receptors. This activation modulates the ERK1/2 signaling pathway and enhances nitric oxide synthesis, both of which play crucial roles in vascular and cardiac function. The peptide's design as a single-chain analog of the B-chain of human relaxin-2 allows it to selectively engage with RXFP1, potentially offering targeted therapeutic effects without the complexity of the full relaxin hormone structure (PMID 31713411, PMID 32295457).
Primary Uses
Receptor Biology Research
B7-33 is extensively utilized in receptor biology research to study GPCR signaling pathways. The peptide's interaction with the RXFP1 receptor provides insights into the signaling mechanisms that govern various physiological responses. This application is currently supported by preclinical studies, and no clinical trials have been conducted in humans.


