Increased urinary 15-F2t-isoprostane concentrations in patients with non-ischaemic congestive heart failure: a marker of oxidative stress

Abstract

Objective: To investigate a novel marker of oxidative stress in patients with congestive heart failure (CHF).

Patients: 15 patients with mild CHF, 15 patients with severe CHF with acute exacerbation, and 15 control subjects.

Main outcome measures: Measurement of urinary 15-F2t-isoprostane, plasma brain natriuretic peptide (BNP), serum interleukin 6 (IL-6), and serum thrombomodulin concentrations. In patients with severe CHF, samples were taken at admission and 4, 7, and 14 days after admission.

Results: Urinary 15-F2t-isoprostane, plasma BNP, and serum IL-6 concentrations in patients with severe CHF were significantly higher than those in control subjects or in patients with mild CHF. However, concentrations of serum thrombomodulin, a marker of endothelial damage, were not different between patients with CHF and control subjects. In addition, urinary 15-F2t-isoprostane, plasma BNP, and serum IL-6 concentrations in patients with severe CHF gradually decreased in proportion to the severity of CHF during hospitalisation. Interestingly, urinary 15-F2t-isoprostane concentrations significantly correlated with plasma BNP concentrations and serum IL-6 concentrations, but not with serum thrombomodulin concentrations.

Conclusions: Urinary 15-F2t-isoprostane concentrations increased in proportion to the severity of CHF in patients. This may be caused by increased 15-F2t-isoprostane production. These findings suggest that urinary 15-F2t-isoprostane may be a marker of morbidity as well as oxidative stress in patients with CHF.

Figures

Figure 1

Urinary 15-F2t-isoprostane (15-F2t-IsoP) concentrations in patients with congestive heart failure (CHF). Scatter plots show the urinary 15-F2t-Iso concentrations in control subjects (n=15), in patients with mild CHF in New York Heart Association (NYHA) functional class I or II (n=15), and in patients with severe CHF in NYHA functional class III or IV (n=15). The data on day 1 are urinary 15-F2t-IsoP concentrations in patients with severe CHF at admission. Bars show median value.

Figure 2

Relation between urinary 15-F2t-IsoP concentrations and plasma brain natriuretic peptide (BNP) concentrations. Regression analysis showed a highly significant relation between the two molecular markers (y = 0.28x + 249.67, r = 0.87, p < 0.0001, n = 45).

Figure 3

Relation between urinary 15-F2t-IsoP concentrations and serum interleukin 6 (IL-6) concentrations. Regression analysis showed a highly significant relation between the two molecular markers (y = 14.50x + 277.27, r = 0.64, p < 0.0001, n = 45).