Peptide Database

APLNR ligand · apelin-13

Apelin is an endogenous peptide that acts as the ligand for the APJ receptor (APLNR), a GPCR expressed throughout the cardiovascular system. It improves cardiac output and vascular tone through both positive inotropy and vasodilation, increases nitric oxide production, and reduces oxidative stress. Research focuses on heart failure, pulmonary arterial hypertension, and its potential to replace or complement established cardiac peptides.

Brain Natriuretic Peptide · Nesiritide

BNP (B-type/brain natriuretic peptide) is a 32-amino-acid hormone secreted by ventricular cardiomyocytes in response to wall stress and volume overload. Clinically, it is the primary biomarker for heart failure diagnosis and prognosis. Recombinant BNP (nesiritide/Natrecor) was approved for acute decompensated heart failure, producing vasodilation and natriuresis. Research into modified natriuretic peptides continues for heart failure therapy.

Serelaxin · H2 relaxin

Relaxin-2 is an endogenous peptide hormone structurally related to insulin, primarily known for its role in pregnancy (cervical ripening, joint laxity). Research discovered its potent anti-fibrotic properties — it remodels collagen networks in heart, kidney, lung, and liver — making it a leading candidate for fibrosis and acute heart failure. Serelaxin (recombinant relaxin) reached Phase 3 trials for acute heart failure with promising early signals but did not meet primary endpoints.

UCN1 · Urocortin

Urocortin 1 (UCN1) is a 40-amino-acid member of the CRH peptide family that activates both CRHR1 and CRHR2 receptors. It has potent cardioprotective effects — improving cardiac contractility, reducing ischemia-reperfusion injury, and stimulating natriuresis — making it a significant heart failure research target. It also modulates anxiety and appetite centrally. Phase 2 trials for chronic heart failure showed improvements in cardiac function.