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We studied the role of galectin-3 (Gal-3) in the expression of alternative activation markers (M2) on macrophage, cytokines, and fibrosis through the temporal evolution of healing, ventricular remodeling, and function after myocardial infarction (MI). C57BL/6J and Gal-3 knockout mice (Lgals3 -/-) were subjected to permanent coronary ligation or sham. We studied i) mortality, ii) macrophage infiltration and expression of markers of alternative activation, iii) cytokine, iv) matrix metalloproteinase-2 activity, v) fibrosis, and vi) cardiac function and remodeling. At 1 week post-MI, lack of Gal-3 markedly attenuated F4/80þ macrophage infiltration and significantly increased the expression of Mrc1 and Chil1, markers of M2 macrophages at the MI zone. Levels of IL-10, IL-6, and matrix metalloproteinase-2 were significantly increased, whereas tumor necrosis factor-a, transforming growth factor-b, and fibrosis were remarkably attenuated at the infarct zone. In Gal-3 knockout mice, scar thinning ratio, expansion, and cardiac remodeling and function were severely affected from the onset of MI. At 4 weeks post-MI, the natural evolution of fibrosis in Gal-3 knockout mice was also affected. Our results suggest that Gal-3 is essential for wound healing because it regulates the dynamics of macrophage infiltration, proinflammatory and anti-inflammatory cytokine expression, and fibrosis along the temporal evolution of MI in mice. The deficit of Gal-3 affected the dynamics of wound healing, thus aggravating the evolution of remodeling and function.

BackgroundHereditary Hemochromatosis (HH) is a genetic condition associated with a systemic iron overload. Heart failure is an important cause of mortality. It has been demonstrated early stages of systolic and diastolic left ventricular dysfunction in previous studies. The aim of the study is to compare the left atrial (LA) function between asymptomatic HH patients and a control group using 2D speckle tracking. MethodsProspective study. LA strain, LA strain rate and LA volumetric parameters during the reservoir, conduit and contraction phases were studied. The LA Stiffness Index was calculated by the ratio between E/e and LA reservoir strain. Results30 patients with HH (90% males, 47 ± 18 years old) and 30 healthy controls (85% males, 45 ± 13 years old) were included. LA volume was similar in both groups. No differences were observed in LA ejection fraction (EF), LA passive EF and LA active ejection fraction between both groups. On the contrary, the HH group had lower LA strain during the reservoir (31.5 ± 6.5% vs 38.3 ± 7.9%; p = 0.002), and conduit phases (-18 ± 7% vs -23.3 ± 6.4%; p = 0.01) and lower LA conduit strain rate (-1.7 ± 0.7 seg − 1 vs -2.1 ± 0.5 seg − 1 ; p = 0.02) than controls. The LA stiffness index was signi cantly higher in the HH group (0.25 ± 0.9 vs 0.19 ± 0.6; p = 0.01). ConclusionsEarly abnormalities in the LA function could be detected by using 2D speckle tracking study despite no evidence of changes in atrial size or volumetric parameters.