Galectin-3 and histological, molecular and biochemical aspects of myocardial fibrosis in heart failure of hypertensive origin

Abstract

Aims: The aim of this study was to investigate whether galectin-3 (Gal-3) is associated with myocardial histological and molecular parameters related to fibrosis and with the circulating biomarkers of the extracellular generation of mature fibril-forming collagen types I (C-terminal propeptide of procollagen type I, PICP) and III (N-terminal propeptide of procollagen type III, PIIINP) in two independent studies of hypertensive patients with heart failure (HF).

Methods and results: Endomyocardial biopsies and blood samples from 39 HF patients (invasive study), and blood samples from 220 HF patients (non-invasive study) were analysed. Necropsies (n = 7) and blood samples (n = 20) from healthy subjects were used as controls. In the invasive study myocardial mRNA and protein expression of Gal-3 and collagen types I and III, plasma Gal-3 and serum PICP and PIIINP were all significantly increased in patients compared with controls. Neither myocardial nor plasma Gal-3 were correlated with myocardial collagen and circulating biomarkers; whereas PICP was correlated with myocardial total (r = 0.819, P < 0.001) and collagen type I (r = 0.744, P < 0.001) deposition, PIIINP was not. In the non-invasive study both plasma Gal-3 and serum PICP were increased (P < 0.001) in patients compared with controls. No correlation was found between Gal-3 and PICP in HF patients.

Conclusions: These findings show that although an excess of cardiac and systemic Gal-3 is present in patients with HF of hypertensive origin, this molecule is not associated with histological, molecular and biochemical parameters related to myocardial fibrosis in these patients.

Keywords: Collagen; Fibrosis; Galectin-3; Heart failure; PICP; PIIINP.