Galectin-3 is associated with severe heart failure and death: A hospital-based study in Chinese patients

The Diagnostic and Prognostic Value of Plasma Galectin 3 in HFrEF Related to the Etiology of Heart Failure

Aim: The aim of present study is to evaluate the diagnostic and prognostic value of plasma galectin 3 (Gal-3) for HF originating from different causes.

Methods: We investigated the plasma levels and expression of Gal-3 in cardiac tissues in two transgenic (TG) strains of mice with cardiomyocyte-restricted overexpression of either β2- adrenergic receptor (β2- AR TG) or Mammalian sterile 20-like kinase 1 (Mst1-TG) in the present study. Additionally, 166 patients suffering from heart failure with reduced ejection fraction (HFrEF) in two hospitals within the Shaanxi province were examined in this study. All these patients were treated according to the Chinese HF guidelines of 2014; subsequently, they were followed up for 50 months, and we analyzed the prediction value of baseline Gal-3 to endpoints in these patients.

Results: Gal-3 was localized in the cytoplasm and nucleus of cardiomyocytes, often formed aggregates in Mst1-TG mice. Extracellular Gal-3 staining was uncommon in Mst1-TG hearts. However, in β2-AR TG mice, although Gal-3 was also expressed in myocardial cells, it was more highly expressed in interstitial cells (e.g., fibroblasts and macrophages). Plasma Gal-3 was comparable between nTG and Mst1-TG mice. However, plasma Gal-3 was higher in β2-AR TG mice than in nTG mice. In the cohort of HFrEF patients, the median plasma Gal-3 concentration was 158.42 pg/mL. All participants were divided into two groups according to Gal-3 levels. Patients with Gal-3 concentrations above the median were older, and had lower plasma hemoglobin, but higher plasma creatinine, tissue inhibitor of metalloproteinases 1 (TIMP-1), left ventricular end systolic diameter (LVESD), left ventricular end-systolic volumes (LVESV) and end-diastolic, as well as left ventricular end-diastolic volumes (LVEDV). Spearman correlation analysis revealed that Gal-3 was positively correlated with TIMP-1 (r = 0.396, P < 0.001), LVESV (r = 0.181, P = 0.020) and LVEDV (r = 0.190, P = 0.015). The 50-month clinical follow-up revealed 43 deaths, 97 unplanned re-hospitalizations, and 111 composite endpoint events. Cox analysis demonstrated that although Gal-3 did not provide any prognostic value in either total-HF subjects or coronary-heart-disease (CHD) patients, it did provide prognostic value in non-CHD patients.

Conclusion: Although plasma Gal-3 is associated with TIMP-1 and echocardiographic parameters, the diagnostic and prognostic value of Gal-3 in HFrEF is determined by the etiology of HF.

Galectin 3 and non-classical monocytes of blood as myocardial remodeling factors at ischemic cardiomyopathy

Aims

To identify an imbalance of cardiac remodeling mediators and monocytes subpopulation in blood, distribution of myocardium macrophages in patients with ischemic cardiomyopathy (ICMP).

Methods

The study engaged 30 patients with ICMP, 26 patients with coronary heart disease (CHD) without ICMP, 15 healthy donors. Concentrations of TGFβ, MMP-9, MCP-1, galectin-3 were measured in plasma of blood from the coronary sinus and peripheral blood in CHD patients, as well as in peripheral blood in healthy donors, by enzyme immunoassay method. The ration of classical, intermediate, non-classical, transitional monocytes in peripheral blood of patients and healthy donors was assessed by flow cytometry (expression CD14, CD16); the content of CD68+ macrophages in myocardium – by immunohistochemistry method.

Results

In both samples of blood, the content of galectin-3 in patients with ICMP was higher than in CHD patients without ICMP and the level of TGFβ was comparable between the groups. At ICMP, the concentration of MMP-9 in sinus blood was higher than that in CHD patients without ICMP in whom an excess of MCP-1 in the general blood flow was determined. The density of distribution of CD68+ cells in the myocardium in patients with ICMP was higher in the perianeurysmal zone than in the right atrium appendage. ICMP was characterized by a deficiency of non-classical monocytes, and CHD without ICMP – by an excess of intermediate cells in peripheral blood.

Conclusion

Myocardium remodeling at ICMP is mediated by not so much TGFβ but intracardiac galectin-3, which determines the subpopulation composition of blood monocytes.

Research progress on the role of gal-3 in cardio/cerebrovascular diseases

Galectin-3 (gal-3), a member of the galectin family, is a glycoprotein with high affinity for β-galactoside. Gal-3 is a cytoplasmically synthesized protein that can shuttle between the cytoplasm and nucleus and can even be transported to the membrane and secreted into the extracellular environment. Cardio/cerebrovascular diseases generally refer to ischemic or hemorrhagic diseases occurring in the heart, brain and systemic tissues, which are characterized by high morbidity, high disability rates and high mortality rates. To date, considerable research has demonstrated that gal-3 expression is aberrantly increased and plays important roles in cardio/cerebrovascular diseases, such as acute ischemic stroke (AIS), myocardial fibrosis, acute coronary syndrome (ACS), and heart failure (HF). Hence, understanding the biological roles of gal-3 in these diseases may be essential for cardio/cerebrovascular disease treatment and diagnosis to improve patient quality of life. In this review, we summarize current research on the roles of gal-3 in human cardiovascular diseases and potential inhibitors of gal-3, which may provide new strategies for disease therapies.