Leptin-Aldosterone-Neprilysin Axis

Obesity (especially visceral adiposity) can be associated with 3 different phenotypes of heart failure: heart failure with a reduced ejection fraction, heart failure with a preserved ejection fraction, and high-output heart failure. All 3 phenotypes are characterized by an excessive secretion of aldosterone and sodium retention. In addition, obesity is accompanied by increased signaling through the leptin receptor, which can promote activation of both the sympathetic nervous system and the renin-angiotensin system and can directly stimulate the secretion of aldosterone. The deleterious interaction of leptin and aldosterone is potentiated by the simultaneous action of adiposity and the renal sympathetic nerves to cause overactivity of neprilysin; the loss of the counterbalancing effects of natriuretic peptides is exacerbated by an additional effect of both obesity and heart failure to interfere with adiponectin signaling. This intricate neurohormonal interplay leads to plasma volume expansion as well as to adverse ventricular remodeling and cardiac fibrosis. Furthermore, the activity of aldosterone and neprilysin is not only enhanced by obesity, but these mechanisms can also promote adipogenesis and adipocyte dysfunction, thereby enhancing the positive feedback loop. Last, in elderly obese women, changes in quantity and biology of epicardial adipose tissue further enhances the release of leptin and other proinflammatory adipokines, thereby leading to cardiac and systemic inflammation, end-organ fibrosis, and multiple comorbidities. Regardless of the phenotypic expression, activation of the leptin-aldosterone-neprilysin axis appears to contribute importantly to the evolution and progression of heart failure in people with obesity. Efforts to interfere with the detrimental interactions of this distinctive neurohormonal ecosystem with existing or novel therapeutic agents are likely to yield unique clinical benefits.