Galectin-3 as a marker for clinical prognosis and cardiac remodeling in acute heart failure

Long-term Dexamethasone Treatment Increases Cardiac Galectin-3 Levels

PURPOSE

Glucocorticoids, which are widely prescribed around the world, cause cardiac remodeling in long-term treatment by triggering insulin resistance and increasing blood pressure. However, its role in cardiac remodeling remains unclear. Galectin-3 (gal-3) is a member of a beta-galactoside-binding animal lectins, upregulated as a result of insulin resistance and in the pressure-overloaded myocardium and regulate cardiac remodeling. We hypothesized that gal-3 may be upregulated in the myocardium with prolonged use of glucocorticoids and associated with cardiac hypertrophy.

METHODS

To examine the involvement of glucocorticoids in gal-3 levels in rat myocardium, sixteen female Wistar Albino rats were assigned to control (C; n = 8) and dexamethasone (Dex; n = 8) groups. Daily dexamethasone was injected subcutaneously for 28 days at a dose of 1 mg.kg-1. Control animals were injected with the same volume of saline. The body weight and heart weights were determined. Gal-3 levels in myocardium were determined by Western blot.

RESULTS

Our data shows that dexamethasone administration resulted in significant increase in heart weight (p < 0.05) and HW/BW ratios (p < 0.001) and 28 days of dexamethasone administration with the dose of 1 mg.kg-1 caused a twofold increase in the gal-3 expression in the left ventricle (p < 0.001).

CONCLUSION

The finding of the current study is the first to show that dexamethasone causes an increase in gal-3 levels in myocardium. Our study provides an important step in the development of possible therapeutics by determining that dexamethasone causes an increase in gal-3 levels in the myocardium and raises awareness about the follow-up of patients receiving long-term glucocorticoid therapy.

Circulating galectin-3 on admission and prognosis in acute heart failure patients: a meta-analysis

Changes of serum galectin-3 have been associated with the pathogenesis of many cardiovascular diseases. The aim of the study was to evaluate the prognostic role of serum galectin-3 in patients with acute heart failure (AHF) in a meta-analysis. Follow-up studies evaluating the association between serum galectin-3 on admission and clinical outcomes in AHF patients were identified via search of PubMed and Embase databases. A random effects or a fixed effects model was applied to pool the results depending on the heterogeneity. Subgroup analysis was used to evaluate the influences of study characteristics on the outcomes. Overall, 7057 AHF patients from eighteen follow-up studies were included. Higher serum galectin-3 was associated with higher risks of all-cause mortality (adjusted risk ratio [RR], 1.58; p < 0.001), mortality/HF rehospitalization (RR, 1.68; p < 0.001), and cardiovascular mortality (RR, 1.29; p = 0.04), but not HF rehospitalization (RR, 1.24; p = 0.25) in AHF patients. Subgroup analyses showed that study characteristics including study design, sample size, age, gender, left ventricular ejection fraction, galectin-3 variable type, follow-up duration, and adjustment of type B natriuretic peptide did not significantly impact the results. Significant heterogeneities were detected for the outcomes of all-cause mortality and mortality/HF rehospitalization. However, trim-and-fill analyses by including the imputed studies to generate symmetrical funnel plots showed similar significant meta-analysis results. These results suggested that higher serum galectin-3 may be associated with poor prognosis in AHF patients. Further studies are needed to determine the mechanisms underlying the potential prognostic role of galectin-3 in AHF.

Biomarkers in diagnosing and treatment of acute heart failure

Acute heart failure (AHF) is a complex disorder involving different pathophysiological pathways. In recent years, there is an increased focus on biomarkers that help with diagnosis, risk stratification and disease monitoring of AHF. Finding a reliable set of biomarkers not only improves morbidity and mortality but it can also potentially reveal the new targets of therapy. In this paper, we have reviewed the biomarkers found useful for the diagnosis as well as for risk stratification and prognostication in patients with AHF. We have discussed the established biomarkers for AHF including cardiac troponins and natriuretic peptides and emerging biomarkers including adiponectin, mi-RNA, sST2, Gal-3, MR-proADM, OPG, CT-proAVP and H-FABP for the purposes of making diagnosis, their use as a guide of therapy or for determination of prognosis.

Establishing the upper reference limit of Galectin-3 in healthy blood donors

Introduction

Galectin-3 (Gal-3) is an independent predictor of poor outcomes and mortality in patients with heart failure (HF). Thus, it has been proposed as a reliable prognostic biomarker for HF. The definition of reference intervals is mandatory for interpreting the findings of experimental studies and encouraging the routine use of biomarkers in clinical practice. To date, no study assessed the reference intervals of Gal-3 and identified the biological variables that affect its concentration in a well-defined healthy population. The aim of this study was to determine the upper reference limit (URL) of Gal-3 in a highly reliable population of healthy subjects.

Materials and methods

We recruited 714 blood donors. After measuring surrogate biomarkers to identify underlying diseases, 8 subjects were excluded. A final population of 706 individuals (385 men (54.5%); median age 39 (18-65) years) was included. The URL was calculated using the non-parametric percentile approach.

Results

The 97.5th percentile URL of plasma Gal-3 in our study population (90% CI) was 26.1 (23.3–31.5) ng/mL. After stratifying subjects according to age, the URL of Gal-3 was found to be considerably higher in older (> 45 years) than in younger subjects (31.5 (26.2–51.4) vs 21.8 (21–26.1) ng/mL, respectively). No sex-related differences were found in Gal-3 plasma concentration.

Conclusions

We established the URL of Gal-3 in a highly selected healthy population. Our findings indicate that age is an important determinant of Gal-3 plasma concentration, so that multiple diagnostic cut-offs should be preferably used according to the different age classes.

Soluble ST2 and Galectin-3 and Progression of CKD

Introduction

Cardiac biomarkers soluble ST2 (sST2) and galectin-3 may reflect cardiac inflammation and fibrosis. It is plausible that these mechanisms may also contribute to the progression of kidney disease. We examined associations of sST2 and galectin-3 with kidney function decline in participants with chronic kidney disease (CKD).

Methods

This was a pooled analysis of 2 longitudinal cohorts of participants with CKD: the Clinical Phenotyping and Resource Biobank (C-PROBE) study and the Seattle Kidney Study (SKS). We measured circulating concentrations of sST2 and galectin-3 at baseline. Our primary outcome was progression to estimated glomerular filtration rate (eGFR) <15 ml/min per 1.73 m² or end-stage renal disease (ESRD). We used competing risk Cox regression models to study the association of sST2 and galectin-3 with CKD progression, adjusting for demographics, kidney function, and comorbidity.

Results

Among the 841 participants in the pooled cohort, baseline eGFR was 51 ± 27 ml/min per 1.73 m² and median urine albumin-to-creatinine ratio (UACR) was 141 (interquartile range = 15−736) mg/g. Participants with higher sST2 and galectin-3 were more likely to be older, to have heart failure and diabetes, and to have lower eGFR. Adjusting for demographics, kidney function, and comorbidity, every doubling of sST2 was not associated with progression to eGFR <15 ml/min per 1.73 m² or ESRD (adjusted hazard ratio 1.02, 95% confidence interval = 0.76−1.38). Every doubling of galectin-3 was significantly associated with a 38% (adjusted hazard ratio = 1.35, 95% confidence interval = 1.01−1.80) increased risk of progression to eGFR <15 ml/min per 1.73 m² or ESRD.

Conclusion

Higher concentrations of the cardiac biomarker galectin-3 may be associated with progression of CKD, highlighting potential novel mechanisms that may contribute to the progression of kidney disease.

Circulating Biomarkers in Heart Failure

Biological markers have served for diagnosis, risk stratification and guided therapy of heart failure (HF). Our knowledge regarding abilities of biomarkers to relate to several pathways of HF pathogenesis and reflect clinical worsening or improvement in the disease is steadily expanding. Although there are numerous clinical guidelines, which clearly diagnosis, prevention and evidence-based treatment of HF, a strategy regarding exclusion of HF, as well as risk stratification of HF, nature evolution of disease is not well established and requires more development. The aim of the chapter is to discuss a role of biomarker-based approaches for more accurate diagnosis, in-depth risk stratification and individual targeting in treatment of patients with HF.