B7-33

B7-33 is a single-chain peptide analog of human relaxin-2 that targets and activates the relaxin family peptide receptor 1 (RXFP1). 

When B7-33 activates RXFP1, it triggers signalling pathways that help reduce fibroblast activity and lower collagen buildup. It also supports tissue remodelling by increasing matrix metalloproteinase (MMP) activity, improves blood vessel relaxation through nitric oxide production, and helps decrease inflammatory cytokine levels.

Compared to natural relaxin-2, B7-33 shows a different signalling profile. It tends to favour activation of the pERK1/2 pathway while producing weaker cAMP signalling. This suggests it acts as a biased agonist at the RXFP1 receptor.

Research areas:

• How β-arrestin is recruited and how the receptor changes shape during activation
• Examining ERK1/2 and Akt signalling activity in heart muscle cells
• Analyzing gene expression linked to heart growth and protective effects
• Testing collagen buildup and how the extracellular matrix is remodelled
• Measuring blood flow and heart function without causing increased blood pressure
• Investigating mitochondrial health and how cell death is controlled in stressed heart tissue