The peptide neuromedin U (NMU) is elevated in NYHA II and III heart failure

Currently, there is no reliable biomarker to detect pre-heart failure in humans. An early risk signal is an elevated left atrial pressure (LAP) and preliminary results from animal studies strongly suggest the neuropeptide neuromedin U (NMU) is released in response to this increase in LAP. However, it is unknown whether NMU is elevated in patients with heart failure. Therefore, the aim of this study was to assess if NMU levels are elevated in human cases of heart failure.

Twenty-four serum samples were obtained from patients in stage II and III heart failure from the Royal Papworth Hospital in Cambridge UK and tested using a selective NMU-ELISA; the data were compared with serum obtained commercially from self-declared healthy donors. NMU concentrations in serum from heart failure patients were significantly higher (P = 0.0007; unpaired Student's t-test) than control, 8.48 ± 0.67 ng/mL (mean ± SEM) versus 5.43 ± 0.46 ng/mL. There was no significant difference between NYHA stage II and III patients (P = 0.85, unpaired Student's t-test), which were 8.33 ± 0.89 ng/mL (n = 9) and 8.6 ± 0.95 ng/mL (n = 15), respectively. Only mean right atrial pressure was found to have a significant correlation with serum NMU (R = 0.81, P < 0.00001; regression analysis).

NMU is elevated in serum from stage II and III heart failure patients, supporting data from our pre-heart failure animal model; however, further study is needed to determine whether NMU is a reliable biomarker for pre-heart failure.