Serum adipokine zinc α2-glycoprotein and lipolysis in cachectic and noncachectic heart failure patients: relationship with neurohormonal and inflammatory biomarkers

Abstract

Chronic heart failure is often complicated by the development of cachexia with the loss of fat mass. Zinc α2-glycoprotein (ZAG) is a serum adipokine with lipolytic effects in cancer cachexia. We evaluated in patients with advanced heart failure with (CxHF) or without cachexia (nCxHF) the relationship of ZAG with circulating free fatty acid (FFA), as an index of lipolysis, and with other neurohormonal and inflammatory biomarkers. Two groups, nCxHF (n = 46) and CxHF (n = 18), the latter having a documented, involuntary, edema-free loss of body weight of at least 7.5% in the previous 6 months, underwent plasma determination of FFA, ZAG, norepinephrine (NE), tumor necrosis factor-α, and natriuretic peptide levels (atrial natriuretic, B-type natriuretic peptide). The patients were compared with age-matched healthy controls (CTR) (n = 21). Zinc α2-glycoprotein, atrial natriuretic peptide, B-type natriuretic peptide, and tumor necrosis factor-α circulating levels were similarly greater in CxHF and nCxHF than in CTR. Free fatty acid and NE were higher in CxHF than in nCxHF. A positive correlation between FFA and NE was found in both CxHF (r = 0.73, P < .01) and nCxHF (r = 0.48, P < .01) but only in CxHF between ZAG and FFA (r = 0.54, P = .02) and between ZAG and NE (r = 0.70, P < .01). No correlations between natriuretic peptides and ZAG were found. Serum ZAG levels are increased in advanced heart failure patients compared with CTR, without differences between CxHF and nCxHF. Only in CxHF, ZAG levels are directly correlated to circulating levels of FFA and NE, suggesting a close interaction of ZAG with sympathetic-mediated lipolysis.