Matrix metalloproteinase-1 and -2 levels are differently regulated in acute exacerbation of heart failure in patients with and without left ventricular systolic dysfunction

Biological variation of extracellular matrix biomarkers in patients with stable chronic heart failure

BACKGROUND

Extracellular matrix (ECM) biomarkers such as matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are pathophysiological key, prognostic marker and therapeutic target in chronic heart failure (HF). Serial measurements of MMPs and TIMPs may be useful for guidance of these applications. However, interpretation of time-dependent changes requires knowledge about the biological variation of ECM biomarkers.

METHODS

We performed measurements of MMP-2, MMP-9, TIMP-1, and TIMP-4 in 50 patients with chronic HF who met rigid criteria for clinical stability at 3-h, 6-h, 1-week and 2-week time intervals. In addition, clinical and haemodynamic assessment was performed at baseline, at 1- and 2-week intervals. Haemodynamic variables were measured using inert gas rebreathing and impedance cardiography. Heart rhythm was monitored with external ECG event recorders throughout the complete study. Reference change values (RCVs) and minimal important differences (MIDs) were determined for MMP-2, MMP-9, TIMP-1, and TIMP-4.

RESULTS

Clinical and haemodynamic variables were stable over time. Depending on the time-interval, RCVs ranged between 4.9 and 11.7% for MMP-2, 26.4 and 56.7% for MMP-9, 10.8 and 30.7% for TIMP-1, and 16.0 and 47.4% for TIMP-4, respectively. The MIDs varied between 43.38 and 65.22 ng/ml for MMP-2, 28.71 and 40.96 ng/ml for MMP-9, 52.32 and 156.07 ng/ml for TIMP-1, and 293.92 and 798.04 pg/ml for TIMP-4, respectively.

CONCLUSION

The biological variation of ECM biomarkers differs with respect to individual biomarkers and time intervals. MMP-2 may be most suitable for serial biomarker measurements, as the biological variation is low irrespective of the time interval between measurements.

Characteristic adaptations of the extracellular matrix in dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is a relatively common heart muscle disease characterized by the dilation and thinning of the left ventricle accompanied with left ventricular systolic dysfunction. Myocardial fibrosis is a major feature in DCM and therefore it is inevitable that corresponding extracellular matrix (ECM) changes are involved in DCM onset and progression. Increasing our understanding of how ECM adaptations are involved in DCM could be important for the development of future interventions. This review article discusses the molecular adaptations in ECM composition and structure that have been reported in both animal and human studies of DCM. Furthermore, we provide a transcriptome-based catalogue of ECM genes that are associated with DCM, generated by using NCBI Gene Expression Omnibus database sets for DCM. Based on this in silico analysis, many novel ECM components involved in DCM are identified and discussed in this review. With the information gathered, we propose putative pathways of ECM adaptations in onset and progression of DCM.

Circulating matrix metalloproteinase patterns in association with aortic dilatation in bicuspid aortic valve patients with isolated severe aortic stenosis

Bicuspid aortic valve (BAV) exhibits a clinical incline toward aortopathy, in which aberrant tensile and shear stress generated by BAV can induce differential expression of matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors (TIMPs). Whether stenotic BAV, which exhibits additional eccentric high-velocity flow jet upon ascending aorta and further worsens circumferential systolic wall shear stress than BAV with echocardiographically normal aortic valve, can lead to unique plasma MMP/TIMP patterns is still unknown. According to their valvulopathy and aortic dilatation status, 93 BAV patients were included in the present study. Group A (n = 37) and B (n = 28) comprised severely stenotic patients with or without ascending aorta dilatation; Group C (n = 12) and D (n = 16) comprised echocardiographically normal BAV patients with or without ascending aorta dilatation. Plasma MMP/TIMP levels (MMP-1, -2, -3, -8, -9, -10, -13 and TIMP-1, -2, -4) were determined via a multiplex ELISA detection system in a single procedure. Among patients with isolated severe aortic stenosis, plasma levels of MMP-2 and -9 were significantly elevated when ascending aortic dilatation was present (p = 0.001 and p = 0.002, respectively). MMP-2, however, remained as the single elevated plasma component among echocardiographically normal BAV patients with dilated ascending aorta (p = 0.027). Multivariate analysis revealed that MMP-2 and MMP-9 could both serve as independent risk factor for aortic dilatation in the case of isolated severe stenosis (p = 0.003 and p = 0.001, respectively), and MMP-2 in echocardiographically normal patients (p = 0.002). In conclusion, BAV patients with isolated severe aortic stenosis demonstrated a distinct plasma MMP/TIMP pattern, which might be utilized as circulating biomarkers for early detection of aortic dilatation.

High serum levels of thrombospondin-2 correlate with poor prognosis of patients with heart failure with preserved ejection fraction

Thrombospondin-2 (TSP-2) is highly expressed in hypertensive heart. Interstitial fibrosis is frequently observed in hypertensive heart, and it is a characteristic feature of heart failure with preserved ejection fraction (HFpEF). We tested here the hypothesis that high TSP-2 serum levels reflect disease severity and can predict poor prognosis of patients with HFpEF. Serum TSP-2 levels were measured by ELISA in 150 patients with HFpEF. HFpEF was defined as left ventricular ejection fraction ≥ 50%, B-type natriuretic peptide (BNP) ≥ 100 pg/ml or E/e' ≥ 15. The endpoints were mortality rate, HF-related hospitalization, stroke and non-fatal myocardial infarction. The median serum TSP-2 level was 19.2 (14.4-26.0) ng/ml. Serum TSP-2 levels were associated with the New York Heart Association (NYHA) functional class. Circulating levels of BNP and high-sensitivity troponin T were positively correlated with serum TSP-2 levels. Kaplan-Meier survival curve showed high risk of adverse cardiovascular events in the high TSP-2 group (>median value), and that the combination of high TSP-2 and high BNP (≥ 100 pg/ml) was associated with the worst event-free survival rate. Multivariate Cox proportional hazard analysis identified TSP-2 as independent predictor of risk of death and cardiovascular events. Circulating TSP-2 correlates with disease severity in patients with HFpEF. TSP-2 is a potentially useful predictor of future adverse cardiovascular events in patients with HFpEF.

Biomarkers of heart failure with normal ejection fraction: a systematic review

AIMS

Heart failure with normal ejection fraction (HFNEF) is a major and growing public health problem, currently representing half of the heart failure burden. Although many studies have investigated the diagnostic and prognostic value of new biomarkers in heart failure, limited data are available on biomarkers other than natriuretic peptides in HFNEF. We performed a systematic review of epidemiological studies on the associations of biomarkers with the occurrence of HFNEF and with the prognosis of HFNEF patients.

METHODS AND RESULTS

Biomarkers examined most extensively in HFNEF include biomarkers of myocyte stress, inflammation, and extracellular matrix remodelling. Some biomarkers have been shown to be increased to a different extent in HFNEF compared with heart failure with reduced ejection fraction (HFREF). Several biomarkers, including biomarkers of myocyte stress, inflammation, extracellular matrix remodelling, growth differentiation factor 15 (GDF-15), cystatin C, resistin, and galectin-3, were associated with development of HFNEF and with clinical outcomes of HFNEF patients in terms of morbidity and mortality.

CONCLUSION

Several biomarkers, including biomarkers of myocyte stress, inflammation, extracellular matrix remodelling, GDF-15, cystatin C, resistin, and galectin-3, appeared to be promising diagnostic and prognostic tools in patients with HFNEF. Investigation of the incremental diagnostic and prognostic value of these biomarkers, or a combination thereof, over established clinical covariates and imaging techniques in large, prospective studies is warranted.

Genetic variants associated with circulating MMP1 levels near matrix metalloproteinase genes on chromosome 11q21-22 in Taiwanese: interaction with obesity

BACKGROUND

MMP1 is implicated in the pathogenesis of atherothrombotic cardiovascular disease. We aimed to elucidate genetic determinants of inflammatory marker levels, including circulating MMP1, in Taiwanese, and their association with obesity.

METHODS

Five genetic polymorphisms around matrix metalloproteinase genes on chromosome 11q21-22 region were genotyped in 519 subjects.

RESULTS

After adjusting for clinical covariates, two polymorphisms were significantly associated with MMP1 levels, rs1799750 and rs495366, using an additive inheritance model (P = 1.5x10-4 and P = 2.57x10-5, respectively). Using dominant model, minor alleles of rs1799750 and rs495366 were associated with higher MMP1 levels (P = 1.3x10-4 and P = 1.95x10-5, respectively). In haplotype analysis, two haplotypes inferred from five SNPs (A2GATA and A1GATG) were associated with MMP1 levels (P = 5x10-4 and P = 8.47x10-5, respectively). Subgroup and interaction analysis revealed an association of rs1799750 and rs495366 with MMP1 levels only in non-obese subjects (P = 6.66x10-6 and P = 4.38x10-5, respectively, and interaction P = 0.008 for rs1799750). Haplotype interaction analysis also showed significant interaction for haplotype A1GATG (interaction P = 0.003).

CONCLUSIONS

Genotypes/haplotypes around MMP1 locus are associated with MMP1 levels in Taiwanese. Further, since genotypes/haplotypes near MMP1 locus interact with obesity to set MMP1 levels, genetic determinants for MMP1 level may be different between obese and non-obese individuals.

Novel cardiac-specific biomarkers and the cardiovascular continuum

The concept of the cardiovascular continuum, introduced during the early 1990s, created a holistic view of the chain of events connecting cardiovascular-related risk factors with the progressive development of pathological-related tissue remodelling and ultimately, heart failure and death. Understanding of the tissue-specific changes, and new technologies developed over the last 25-30 years, enabled tissue remodelling events to be monitored in vivo and cardiovascular disease to be diagnosed more reliably than before. The tangible product of this evolution was the introduction of a number of biochemical markers such as troponin I and T, which are now commonly used in clinics to measure myocardial damage. However, biomarkers that can detect specific earlier stages of the cardiovascular continuum have yet to be generated and utilised. The majority of the existing markers are useful only in the end stages of the disease where few successful intervention options exist. Since a large number of patients experience a transient underlying developing pathology long before the signs or symptoms of cardiovascular disease become apparent, the requirement for new markers that can describe the early tissue-specific, matrix remodelling process which ultimately leads to disease is evident. This review highlights the importance of relating cardiac biochemical markers with specific time points along the cardiovascular continuum, especially during the early transient phase of pathology progression where none of the existing markers aid diagnosis.

Administration of angiotensin-converting enzyme inhibitors is associated with slow progression of mild aortic stenosis in Japanese patients

It is almost unknown which demographic factors or medications affect the progression of aortic stenosis (AS) in Japanese patients with mild AS. We identified a total of 194 patients with native tricuspid valvular AS, defined as a continuous-wave Doppler determined peak aortic valve jet velocity of ≥ 2.0 m/s, in whom echo Doppler studies were repeated at an interim of at least 6 months. Annualized change in peak jet velocity was calculated, and effects of age, sex, diabetes mellitus, blood pressure, serum low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglyceride levels, and use of statins and antihypertensive agents on the progression of AS were retrospectively evaluated. Peak aortic valve jet velocity was 2.36 ± 0.79 m/s (mean ± SD) and annualized increase in peak aortic valve jet velocity was 0.17 ± 0.32 m/s/year for all the studied patients. The increase in peak aortic valve jet velocity was lower in patients taking angiotensin-converting enzyme inhibitors (ACE-Is) than in those not taking ACE-Is (0.04 ± 0.22 vs. 0.20 ± 0.32 m/s/year, P < 0.05). Such protective associations were not observed for other first-line antihypertensive agents and statins. Multiple linear regression analysis revealed that ACE-I treatment, decrease in left ventricular ejection fraction, and higher peak aortic valve jet velocity at the first echocardiogram were associated with slower progression of AS. Administration of ACE-Is was associated with the slow progression of mild AS in Japanese patients. Prospective study to assess this hypothesis is needed.

Effects of telmisartan on markers of ventricular remodeling in patients with acute myocardial infarction: comparison with enalapril

Enalapril is effective in the suppression of left ventricular remodeling after acute myocardial infarction (AMI), but the effect of telmisartan is unclear. The consecutive 163 AMI patients underwent primary percutaneous coronary intervention and were randomized to telmisartan (n = 82) or enalapril (n = 81). Left ventriculography was performed in the acute and chronic (6 months) phases. Matrix metalloproteinase (MMP)-2 and MMP-9 activities were measured by zymography in the acute (days 1, 7, and 14) and chronic (6 months) phases. Plasma pentraxin3 (PTX3), a marker of vascular inflammation, was also measured. There were no adverse effects in the telmisartan group. The analysis of the left ventriculograms in the acute and chronic phases revealed no difference between the two groups. MMP-9 activities at days 7 and 14 and in the chronic phase were decreased compared to that at day 1 in both groups. MMP-2 activity was also decreased in the acute phase, but increased in the chronic phase in both groups. There was no difference in the plasma PTX3 level in the acute phase, but in the chronic phase, PTX3 was significantly lower in telmisartan than in enalapril group (2.6 ± 1.4 vs. 3.2 ± 1.6 ng/ml, p = 0.04). Telmisartan is well tolerated, shows similar effects on the markers of left ventricular remodeling to those of enalapril, and suppresses vascular inflammation more effectively than enalapril in AMI patients. Telmisartan can be an alternative to angiotensin converting enzyme inhibitor in patients with AMI.

Cytokines and matrix metalloproteinases as potential biomarkers in chronic heart failure

Heart failure (HF) is accompanied by the upregulation of bioactive signaling molecules, known as cytokines, and a family of downstream proteases, matrix metalloproteinases (MMPs). It is now apparent that these molecules contribute to adverse myocardial remodeling during HF. Elevated levels of cytokines and MMPs exist in the myocardium and can subsequently spill over into the systemic circulation. The purpose of this article is to examine clinical studies of HF that have quantified levels of different types of cytokines, MMPs and endogenous tissue inhibitors of MMPs in relation to this disease process. HF is a complex syndrome that can develop from various etiologies and can be characterized into two distinct phenotypes: systolic and diastolic. This article will present recent clinical studies that have identified significant differences between the cytokine and MMP circulating profile of systolic and diastolic HF patients. In general, elevated levels of cytokines and MMPs exist in systolic HF patients when compared with diastolic HF patients, whereas diastolic HF patients have elevated levels of cytokines and MMPs when compared with controls. Therefore, future studies distinguishing between HF phenotypes may provide more consistent results in determining possible analytes to be used as biomarkers. Furthermore, this article will emphasize why standardization of analytical techniques and establishment of referent cytokine and MMP levels are necessary if these analytes are to be used as biomarkers for the diagnosis, prognosis and evaluation of treatment in the context of HF.