Masahide Sawaki

Interleukin-6 Spillover in the Peripheral Circulation Increases With the Severity of Heart Failure, and the High Plasma Level of Interleukin-6 Is an Important Prognostic Predictor in Patients With Congestive Heart Failure

OBJECTIVES We 1) evaluated whether interleukin-6 (IL-6) is produced in the peripheral circulation in patients with congestive heart failure (CHF), 2) estimated the factors for increased IL-6, and 3) clarified the prognostic role of high plasma levels of IL-6 in patients with CHF. BACKGROUND Although plasma levels of IL-6 have been reported to increase in patients with CHF, and production of IL-6 in endothelial cells and vascular smooth muscle cells has been postulated from in vitro studies, the origin of the increase of IL-6 in CHF remains unknown. Moreover, the prognostic value of a high plasma level of IL-6, independent of classic neurohumoral factors, remains to be elucidated. METHODS A comparison was made of the plasma levels of IL-6 between the femoral artery and the femoral vein in 13 normal subjects and in 80 patients with CHF. In another study, we measured plasma IL-6 in 100 patients with CHF and follow-up data. RESULTS Plasma IL-6 levels increased significantly from the femoral artery to the femoral vein in normal subjects and in patients with CHF. Arteriovenous IL-6 spillover in the leg increased with the severity of CHF. Among the hemodynamic variables and the various neurohumoral factors, the plasma norepinephrine (NE) level showed an independent and significant positive relation with the plasma IL-6 level in patients with CHF. Moreover, treatment with beta-adrenergic blocking agents showed an independent and significant negative relation with plasma IL-6 levels. In 100 patients, plasma IL-6 (p < 0.0001), NE (p = 0.0004) and left ventricular ejection fraction (0.015) were significant independent prognostic predictors by Cox proportional hazards analysis. CONCLUSIONS Our findings indicate that the IL-6 spillover in the peripheral circulation increases with the severity of CHF and that the increase in plasma IL-6 is mainly associated with the activation of the sympathetic nervous system. High plasma levels of IL-6 can provide prognostic information in patients with CHF, independent of left ventricular ejection fraction and plasma NE, suggesting an important role for IL-6 in the pathophysiology of CHF.

High levels of plasma brain natriuretic peptide and interleukin-6 after optimized treatment for heart failure are independent risk factors for morbidity and mortality in patients with congestive heart failure ☆

OBJECTIVES The aim of this study was to evaluate whether repetitive measurements of plasma levels of neurohumoral factors and cytokines before and after additional treatment are useful for predicting mortality in patients with congestive heart failure (CHF). BACKGROUND Neurohumoral and immune activation play an important role in the pathophysiology of CHF. However, the effects of serial changes in these factors on the prognostic value remain unknown. METHODS We measured plasma levels of neurohumoral factors and cytokines and left ventricular ejection fraction (LVEF) before and three months after optimized treatment for CHF in 102 consecutive patients with severe CHF (New York Heart Association class III to IV) on admission to our hospital. Physicians who were blind to the plasma neurohumoral factors until study completion treated patients using standard drugs. Patients were monitored for a mean follow-up period of 807 days. RESULTS Plasma levels of neurohumoral factors, cytokines and LVEF were significantly improved three months after optimized treatment. Cardiac death occurred in 26 patients. Among 19 variables including LVEF, only a high level of brain natriuretic peptide (BNP) and interleukin-6 (IL-6) at three months after optimized treatment showed significant independent relationships by Cox proportional hazard analysis with a high mortality for patients with CHF. CONCLUSIONS These findings indicate that high plasma BNP and IL-6 levels three months after optimized treatment are independent risk factors for mortality in patients with CHF, suggesting that sustained high plasma levels of BNP and IL-6 after additional standard treatment were independent risk factors for mortality in patients with CHF despite improvements in LVEF and symptoms.

Effect of spironolactone on plasma brain natriuretic peptide and left ventricular remodeling in patients with congestive heart failure

OBJECTIVES We sought to evaluate the effects of spironolactone on neurohumoral factors and left ventricular remodeling in patients with congestive heart failure (CHF). BACKGROUND Aldosterone (ALD) promotes collagen synthesis and structural remodeling of the heart. Spironolactone, an ALD receptor antagonist, is reported to reduce mortality in patients with CHF, but its influence on left ventricular remodeling has not been clarified. METHODS Thirty-seven patients with mild-to-moderate nonischemic CHF were randomly divided into two groups that received treatment with spironolactone (n = 20) or placebo (n = 17). We measured left ventricular volume and mass before treatment and after four months of treatment. We also measured the plasma levels of neurohumoral factors, such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), as well as plasma procollagen type III aminoterminal peptide (PIIINP), a marker of myocardial fibrosis. RESULTS Left ventricular volume and mass were significantly decreased and ejection fraction was significantly increased in the spironolactone group, while there were no changes in the placebo group. Plasma levels of ANP, BNP and PIIINP were significantly decreased after spironolactone treatment, but were unchanged in the placebo group. There was a significant positive correlation between the changes of PIIINP and changes of the left ventricular volume index (r = 0.45, p = 0.045) as well as the left ventricular mass index (r = 0.65, p = 0.0019) with spironolactone treatment. CONCLUSIONS These findings indicate that four months of treatment with spironolactone improved the left ventricular volume and mass, as well as decreased plasma level of BNP, a biochemical marker of prognosis and/or ventricular hypertrophy, suggesting that endogenous aldosterone has an important role in the process of left ventricular remodeling in nonischemic patients with CHF.

Angiotensin II type 1 receptor antagonist decreases Plasma levels of tumor necrosis factor alpha, interleukin-6 and soluble adhesion molecules in patients with chronic heart failure

OBJECTIVES To evaluate the effects of an angiotensin (Ang II) type 1 receptor antagonist on immune markers in patients with congestive heart failure (CHF). BACKGROUND Ang II stimulates production of immune factors via the Ang II type 1 receptor in vitro, and the long-term effects of Ang II type 1 receptor antagonists on plasma markers of immune activation are unknown in patients with CHF. METHODS Twenty-three patients with mild to moderate CHF with left ventricular dysfunction were randomly divided into two groups: treatment with Ang II type 1 receptor (candesartan cilexetil) (n = 14) or placebo (n = 9). We measured plasma levels of immune factors such as tumor necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1). We also measured plasma levels of the neurohumoral factors such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) and cyclic guanosine monophosphate (cGMP), a biological marker of ANP and BNP. RESULTS Plasma levels of TNFalpha, IL-6, sICAM-1 and sVCAM-1 were increased in the 23 CHF patients compared with normal subjects and significantly decreased after 14 weeks of candesartan cilexetil treatment, but did not change in the placebo group. Plasma levels of BNP, which is a marker of ventricular injury, significantly decreased, and the molar ratio of plasma cGMP to cardiac natriuretic peptides (ANP + BNP) was significantly increased after candesartan cilexetil treatment, but did not change in the placebo group. CONCLUSIONS These findings suggest that 14 weeks of treatment with an Ang II type 1 receptor antagonist (candesartan cilexetil) decreased plasma levels of the immune markers such as TNFalpha, IL-6, sICAM-1 and sVCAM-1 and that it improved the biological compensatory action of endogenous cardiac natriuretic peptides in patients with mild to moderate CHF.

Relationship between tumor necrosis factor-alpha production and oxidative stress in the failing hearts of patients with dilated cardiomyopathy

OBJECTIVES This study evaluated oxidative stress in the failing ventricle in patients with dilated cardiomyopathy (DCM). BACKGROUND Oxidative stress appears to increase in the failing myocardium and may contribute to ventricular dysfunction in patients with DCM. Tumor necrosis factor-alpha (TNF-alpha), which is expressed in the failing heart, may stimulate oxidative stress. METHODS We measured plasma oxidized low density lipoprotein (oxLDL) by sandwich enzyme-linked immunosorbent assay using specific antibodies against oxLDL in the aortic root (AO) and the coronary sinus (CS) in control subjects (n = 8) and in 22 patients with DCM and mild congestive heart failure. We also measured the plasma levels of TNF-alpha and angiotensin II. RESULTS There was no difference in oxLDL between the AO and CS in control subjects. In contrast, plasma oxLDL was significantly higher in the CS than the AO in patients with DCM, suggesting that the transcardiac gradient ofoxLDL reflects oxidative stress in the failing heart in these patients. Plasma TNF-alpha levels were significantly higher in the CS than the AO with a significant positive correlation of the transcardiac gradient of TNF-alpha and the transcardiac gradient of oxLDL. Moreover, a significant negative correlation existed between the transcardiac gradient of oxLDL and left ventricular ejection fraction. The transcardiac gradient of plasma oxLDL was significantly lower in 6 patients who received carvedilol than in 16 patients who did not receive carvedilol. CONCLUSIONS These findings indicate that the transcardiac gradient of oxLDL may be a marker of oxidative stress in the heart and that left ventricular dysfunction may be partly due to the oxidative stress in patients with DCM. In addition, TNF-alpha may stimulate oxidative stress in the failing heart in patients with DCM.

Spironolactone inhibits the transcardiac extraction of aldosterone in patients with congestive heart failure

OBJECTIVES The study evaluated the transcardiac extraction or spillover of aldosterone (ALDO) in normal subjects and in patients with congestive heart failure (CHF). BACKGROUND Aldosterone promotes collagen synthesis and structural remodeling of target organs such as the heart. Spironolactone, an ALDO receptor antagonist, has recently been reported to reduce the mortality of patients with CHF; however, the effects of spironolactone on the transcardiac gradient of ALDO have not been clarified. METHODS We measured plasma ALDO in the aortic root (AO) and coronary sinus (CS) in normal subjects and 113 consecutive CHF patients and also measured plasma procollagen type III aminoterminal peptide (PIIINP) in CS, a biochemical marker of myocardial fibrosis. RESULTS Plasma ALDO was significantly lower in the CS than in the AO in normal subjects (n = 15; 61.2 +/- 9.3 vs. 83.1 +/- 11.8 pg/ml, p < 0.0001). In 96 CHF patients who did not receive spironolactone, plasma ALDO was significantly lower in the CS than in the AO (59.3 +/- 3.9 vs. 73.8 +/- 4.9 pg/ml, p < 0.0001). In contrast to the difference in these 96 patients, there was no significant difference in ALDO between the AO and CS in 17 patients who received spironolactone (127.4 +/- 20 vs. 124.0 +/- 19 pg/ml, p = 0.50). Stepwise multivariate analyses showed that spironolactone therapy had an independent and significant negative relationship with the transcardiac gradient of plasma ALDO in patients with CHF. In addition, significant positive correlations were seen between the transcardiac gradient of plasma ALDO and PIIINP (r = 0.565, p < 0.0001) and the left ventricular end-diastolic volume index (r = 0.484, p < 0.0001). CONCLUSIONS These results indicate that plasma ALDO is extracted through the heart in normal subjects and in CHF patients who do not receive spironolactone and that spironolactone inhibits the transcardiac extraction of ALDO in CHF patients, suggesting that spironolactone blocks the effects of ALDO on the failing heart in patients with CHF.

Effects of a specific endothelin-converting enzyme inhibitor on cardiac, renal, and neurohumoral functions in congestive heart failure : Comparison of effects with those of endothelin a receptor antagonism

BACKGROUND--Endothelin (ET)-1 is generated from big ET-1 by endothelin-converting enzyme (ECE). Plasma big ET-1 and ET-1 levels are strongly related to survival in patents with congestive heart failure (CHF). Because selective enzymatic processing of ET-1 formation appears to be an important therapeutic target for CHF, we investigated the acute effects of a specific ECE inhibitor on cardiorenal and endocrine functions in CHF compared with those of a selective ETA receptor antagonist. METHODS AND RESULTS--CHF was induced in beagle dogs by rapid right ventricular pacing (270 bpm, 14 days). Two incremental doses of a specific ECE inhibitor, FR901533, or a selective ETA receptor antagonist, FR139317 (1 and 3 mg/kg, n=8, respectively), were injected into dogs with CHF. FR901533 and FR139317 decreased mean arterial pressure and pulmonary capillary wedge pressure associated with reduction in systemic and pulmonary vascular resistance. These agents increased cardiac output but did not affect left ventricular fractional shortening. FR139317 exerted a greater depressor effect on mean arterial pressure than FR901533 (P<0.05). These agents decreased plasma atrial natriuretic peptide levels, but only FR901533 decreased plasma renin activity, angiotensin II, and aldosterone levels. Neither agent changed the plasma norepinephrine level despite the fall in blood pressure. These drugs increased the urinary water and sodium excretion rate associated with increases in the glomerular filtration rate and renal plasma flow, and the incremental magnitude induced by FR139317 was larger than that by FR901533 (P<0.05). CONCLUSIONS--An ETA receptor antagonist appeared to induce greater vasodilative effects on systemic and renal vasculature in CHF than an ECE inhibitor. However, the ECE inhibitor reduced the secretion of neurohumoral factors that are activated in proportion to the severity of CHF. Our acute complementary data may support the importance of the role of ECE in CHF and provide a rationale foundation for investigating the usefulness of long-term treatment with ECE inhibitors in CHF.

Relationship between endothelin-1 extraction in the peripheral circulation and systemic vascular resistance in patients with severe congestive heart failure☆

OBJECTIVES This study was done to determine the spillover and extraction of endothelin-1 (ET-1) in the peripheral circulation, and to evaluate the factors that regulate local ET-1 extraction in the peripheral circulation in patients with congestive heart failure (CHF). BACKGROUND The relationship between the spillover and extraction of the ET-1 in the peripheral circulation and systemic vascular resistance (SVR) has not been fully clarified. METHODS We measured plasma levels of ET-1 both in femoral artery (FA) and femoral vein (FV) in 93 patients with CHF. RESULTS Plasma ET-1 was significantly higher in FV than in FA in New York Heart Association (NYHA) functional class II patients, but there was no difference of ET-1 between FA and FV in functional class III patients. In patients with functional class IV, plasma ET-1 was significantly lower in FV than in FA, and SVR was significantly higher than in patients with NYHA class II or class III. Moreover, a significant positive correlation existed between plasma ET-1 extraction across the lower leg and SVR in these patients. Among the various neurohumoral factors and hemodynamics, plasma levels of ET-1, angiotensin II in the FA showed an independent and significant relationship with the plasma arteriovenous difference of ET-1 in the lower limb. CONCLUSIONS Circulating ET-1 is extracted in peripheral circulation in patients with severe CHF, suggesting the possibility of upregulation of ET receptors of vascular beds in the lower limb in these patients. The peripheral extraction of ET-1 correlates with SVR in severe CHF patients and is mainly regulated by the local ET-1 and renin angiotensin systems.

Transcardiac extraction of circulating endothelin-1 across the failing heart

To determine the transcardiac gradient of plasma endothelin-1 (ET-1) in patients with congestive heart failure (CHF), we measured plasma levels of ET-1 in both the aortic root and the coronary sinus in 14 normal subjects and 79 consecutive patients with CHF. In normal subjects, plasma ET-1 was significantly higher in the coronary sinus than in the aortic root; these findings were also shown in patients with mild CHF, suggesting that there was ET-1 spillover across the heart. In contrast, plasma ET-1 was significantly lower in the coronary sinus than in the aortic root in patients with severe CHF, suggesting there was ET-1 extraction across the heart in patients with severe CHF. The transcardiac gradient of plasma ET-1 was correlated with the left ventricular end-diastolic volume index (r = 0.501, p <0.0001) and plasma level of procollagen type III amino terminal peptide in the coronary sinus (r = 0.54, p = 0.0008), a marker of myocardial fibrosis. Stepwise multivariate analysis showed that the transcardiac gradient of plasma ET-1 was an independent and significant relation with the left ventricular end-diastolic volume index in patients with CHF (r = 0.665, p <0.0001). These findings suggest that elevated circulating ET-1 is extracted across the failing heart with a significant correlation between the transcardiac gradient of plasma ET-1 and the left ventricular end-diastolic volume index, suggesting that ET receptors are upregulated in the failing ventricle and that the elevated circulating ET-1 might stimulate the process of left ventricular remodeling in patients with severe CHF.

Endothelin-1 promotes vascular structural remodeling during the progression of heart failure prevention of vascular remodeling using a specific endothelin-converting enzyme inhibitor.

To evaluate the effects of endothelin (ET)-converting enzyme (ECE) inhibitor on vascular remodeling in dogs with congestive heart failure (CHF), we chronically administered an ECE inhibitor, FR901533 (FR, iv. 0.3mg/kg/hr, n=6), to dogs with CHF induced by rapid ventricular pacing. Vehicle CHF dogs were given saline (n=7). In the vehicle CHF group after 3 weeks of pacing, the ET system was activated in the plasma and vasculature (3 and 5 times higher than normal, respectively). Inward remodeling occurred in the femoral artery; medial thickness (MT, 225+/-5 vs 193+/-4 microm, P<0.05) and deposition of collagen (DC, 22+/-2 vs 17+/-1%, P<0.01) significantly increased, while lumen diameter (LD, 1173+/-39 vs 1481+/-44 microm, P<0.05) decreased in the femoral artery with CHF compared with the normal femoral artery. There were significant correlations between the number of ET-1 positive cells and MT, DC, LD and systemic vascular resistance. FR significantly suppressed the changes in these vascular parameters compared with the changes in the vehicle CHF group despite the lack of an effect on blood pressure, and moreover FR caused decreases in ET-1 levels in both the plasma and femoral artery (reduced to 43% and 54%, respectively, of the levels in the vehicle CHF group, P<0.05). In conclusion, ET-1 plays a critical role in the structural deterioration of the vasculature during the progression of CHF, and ECE inhibitors can prevent the development of vascular remodeling.