Associations among circulating levels of follistatin-like 1, clinical parameters, and cardiovascular events in patients undergoing elective percutaneous coronary intervention with drug-eluting stents

Follistatin-like 1 (FSTL1) levels as potential early biomarker of cardiovascular disease in a Mexican population

Cardiovascular diseases (CVD) are the leading cause of death globally. In recent years, follistatin-like protein 1 (FSTL1) has been proposed as an emerging potential clinical biomarker of CVD, since its concentration is upregulated in heart failure. The aim of the present study was to evaluate the association of FSTL1 levels and classic biomarkers with the risk of CVD in Mexican population. A case-control study was carried out in patients with cardiovascular diseases (CVD), arterial hypertension, but not CVD (cardiovascular risk factor-CRF), and healthy controls (control group) from the Mexican Institute of Social Security. Lipid profile, homocysteine (Hcys), serum amyloid A (SAA), FSTL1 concentration, PON1 concentration and activities [Arylesterase (ARE), and Lactonase (LAC)] were evaluated. High levels of FSTL1 were found in the CRF group and a positive association of FSTL1 (OR = 4.55; 95% CI 1.29-16.04, p = 0.02) with the presence of arterial hypertension, as well as Hcys (OR, 3.09; 95% CI 1.23-7.76, p = 0.02) and SAA (OR, 1.03; 95% CI 1.01-1.05, p < 0.01) with the presence of CVD. LAC activity (OR, 0.26; 95% CI 0.07-0.94, p = 0.04) and PON1 concentration (OR, 0.17; 95% CI 0.05-0.62, p = 0.01) were associated with a decrease in OR belonging to the group with CVD. Our results suggest that FSTL1 may be a useful biomarker for monitoring cardiovascular risk in clinical settings. However, longitudinal studies are needed to evaluate how FSTL1 could influence the association of PON1 activity and Hcys with CVD.

Follistatin-like 1 and its paralogs in heart development and cardiovascular disease

Cardiovascular diseases (CVDs) are a group of disorders affecting the heart and blood vessels and a leading cause of death worldwide. Thus, there is a need to identify new cardiokines that may protect the heart from damage as reported in GBD 2017 Causes of Death Collaborators (2018) (The Lancet 392:1736-1788). Follistatin-like 1 (FSTL1) is a cardiokine that is highly expressed in the heart and released to the serum after cardiac injury where it is associated with CVD and predicts poor outcome. The action of FSTL1 likely depends not only on the tissue source but also post-translation modifications that are target tissue- and cell-specific. Animal studies examining the effect of FSTL1 in various models of heart disease have exploded over the past 15 years and primarily report a protective effect spanning from inhibiting inflammation via transforming growth factor, preventing remodeling and fibrosis to promoting angiogenesis and hypertrophy. A better understanding of FSTL1 and its homologs is needed to determine whether this protein could be a useful novel biomarker to predict poor outcome and death and whether it has therapeutic potential. The aim of this review is to provide a comprehensive description of the literature for this family of proteins in order to better understand their role in normal physiology and CVD.

Association between Plasma Follistatin-like Protein 1 Levels and the Presence and Severity of Coronary Artery Disease

Follistatin-like protein 1 (FSTL1) is a secreted glycoprotein known for its role in inflammation. However, plasma FSTL1 levels in patients with coronary artery disease (CAD) have not been fully elucidated. Thus, in this study, we investigated the plasma FSTL1 levels of 350 patients who underwent elective coronary angiography. The severity of CAD was represented as the numbers of > 50% stenotic vessels and segments and the severity score. CAD was detected in 196 patients, of whom 84 had 1-vessel disease (1-VD), 62 had 2-VD, and 50 had 3-VD. Plasma high-sensitivity C-reactive protein (hsCRP) levels were higher in patients with CAD than in those without CAD (median 0.56 versus 0.44 mg/L, P < 0.01). Notably, plasma FSTL1 levels were higher in patients with CAD than in those without CAD (median 4.05 versus 3.47 ng/mL, P < 0.02). A stepwise increase in FSTL1 levels was found depending on the number of > 50% stenotic vessels: 3.47 in CAD (-), 3.74 in 1-VD, 4.42 in 2-VD, and 4.65 ng/mL in 3-VD (P < 0.05). FSTL1 levels also correlated with the number of > 50% stenotic segments and the severity score (r = 0.14 and r = 0.15, respectively, P < 0.005) and hsCRP levels (r = 0.10, P < 0.05). In the multivariate analysis, FSTL1 levels were an independent factor associated with CAD. The odds ratio for CAD was 1.61 (95% CI = 1.01-2.58) for high FSTL1 level of > 3.6 ng/mL (P < 0.05). In conclusion, plasma FSTL1 levels in patients with CAD were found to be high and associated with the presence and severity of CAD, thus, suggesting that FSTL1 may play a role in the progression of coronary atherosclerosis.

Proteome dynasmics and bioinformatics reveal major alterations in the turnover rate of functionally related cardiac and plasma proteins in a dog model of congestive heart failure

Protein pool turnover is a critically important cellular homeostatic component, yet it has been little explored in the context of heart failure (HF) pathophysiology. We employed in vivo ²H labeling/ proteome dynamics for non-biased discovery of turnover alterations involving functionally linked cardiac and plasma proteins in canine tachypacing-induced HF, an established preclinical model of dilated cardiomyopathy. Compared to control, dogs with congestive HF displayed bidirectional turnover changes of 28 cardiac proteins, i.e. reduced half-life of several key enzymes involved in glycolysis, homocysteine metabolism and glycogenesis, and increased half-life of proteins involved in proteolysis. Changes in plasma proteins were more modest: only 5 proteins, involved in various functions including proteolysis inhibition, hemoglobin, calcium and ferric-iron binding, displayed increased or decreased turnover rates. In other dogs undergoing cardiac tachypacing, we infused for 2 weeks the myokine Follistatin-like protein 1 (FSTL1), known for its ameliorative effects on HF-induced alterations. Proteome dynamics proved very sensitive in detecting the partial or complete prevention, by FSTL1, of cardiac and plasma protein turnover alterations. In conclusion, our study unveiled, for the first time in a large mammal, numerous HF-related alterations that may serve as the basis for future mechanistic research and/or as conceptually new molecular markers.