Central neurotranspeptide, alpha-melanocyte-stimulating hormone (alpha-MSH) is upregulated in patients with congestive heart failure.

BACKGROUND Alpha-melanocyte-stimulating hormone (alpha-MSH), a pro-opiomelanocortin (POMC) derivative, is a neuropeptide with potent anti-inflammatory properties that inhibits tissue injury in a wide array of inflammation models. OBJECTIVE To determine if alpha-MSH is involved in the development of congestive heart failure (CHF) with the specific aim of examining its peripheral source and one of the mechanisms. METHODS The circulating levels of alpha-MSH were measured in 115 patients with CHF using a double-antibody radioimmunoassay. To determine one of the sources of circulating alpha-MSH, human peripheral blood mononuclear cells (PBMC) were stimulated with lipopolysaccharide (LPS) or tumor necrosis factor (TNF)-alpha. Furthermore, to clarify one of the functions of alpha-MSH, PBMC were cultured in the presence or absence of alpha-MSH. RESULTS Plasma levels of alpha-MSH were significantly higher in NYHA class II patients with CHF than in control subjects (p<0.0001). A significant correlation was found between the levels of alpha-MSH and high-sensitive testing for C-reactive protein in patients with CHF (r=0.41, p<0.0005). PBMC stimulated with LPS or TNF-alpha released alpha-MSH in a concentration-dependent manner. alpha-MSH inhibited LPS-induced TNF-alpha production, and alpha-MSH simultaneously augmented production of interleukin (IL)-10 by PBMC. CONCLUSIONS Circulating alpha-MSH was increased in patients with CHF. Inflammatory response induced alpha-MSH production in cultured human PBMC. Treatment of alpha-MSH could modify the immunobalance between inflammatory and anti-inflammatory responses in cultured PBMC. These findings suggest that alpha-MSH may play an important role in the pathophysiology of CHF.