Circulating Irisin and esRAGE as Early Biomarkers of Decline of Metabolic Health.

A decline in metabolic health may take place before observing any alteration in the levels of the traditional metabolic markers. New indicators of metabolic derangement are therefore compelling. Irisin is a myokine with important metabolic functions. The role of irisin as a metabolic biomarker in humans has not been fully established yet. We quantified plasma irisin and esRAGE in 106 apparently healthy individuals and we performed a cluster analysis to evaluate their associations with metabolic profile. Plasma levels of various traditional markers of metabolic risk (i.e., glucose and lipid levels) were all within the ranges of normality. We identified two clusters of individuals. Compared to cluster 2, individuals in cluster 1 had higher irisin levels, a metabolic profile shifted toward the limits of the reference ranges and lower esRAGE levels. The traditional metabolic blood tests seem not to be enough to identify a metabolic decline early. Irisin increase and esRAGE decrease may reflect a metabolic derangement at the beginning of its development. The role of these molecules as early biomarkers of decline of metabolic health seems an interesting topic to be further explored.

Neutrophil gelatinase-associated lipocalin and acute kidney injury in endovascular aneurysm repair or open aortic repair: a pilot study.

INTRODUCTION: Acute kidney injury (AKI) occurs frequently after abdominal aortic surgery and there is currently no effective marker able to detect early onset. The aim of this study is to evaluate the ability of neutrophil gelatinase-associated lipocalin (NGAL) to early identify the development of acute renal damage in patients undergoing endovascular aneurysm repair (EVAR) or open aortic repair (OAR). MATERIALS AND METHODS: Serial samples of blood and urine were obtained from 25 patients undergoing both EVAR and OAR. Seven male subjects with AKI and 18 subjects with no-AKI (17 males, 1 female) were included in the study. We determined concentrations of serum creatinine (sCr) and urinary, serum and whole blood NGAL (uNGAL, sNGAL, bNGAL) collected at baseline, and after 4 and 18 hours. AKI was defined according to the RIFLE criteria (risk, injury, failure, loss of kidney function, and end-stage kidney disease): increase by 50% in sCr or reduction of at least 25% of estimated glomerular filtration rate (eGFR) from baseline. RESULTS: Seven patients developed AKI in the stage Risk. There was no significant difference in sNGAL concentrations in the AKI group as compared to no-AKI group. However, the uNGAL/uCreatinine ratio and bNGAL concentrations were significantly higher after 18 hours in the AKI group (no-AKI 1.69 (0.91 - 2.47) vs AKI 3.2 (2.08 - 5.92) ng/mg for uNGAL/uCreatinine ratio, P = 0.036; and no-AKI 83 (59 - 131) vs AKI 164 (126 - 263) ng/mL for bNGAL, P = 0.029). CONCLUSIONS: Our results suggest that uNGAL, sNGAL and bNGAL, after abdominal aortic surgery, are not suitable as early biomarkers of AKI.

Cardiac involvement in myotonic dystrophy: The role of troponins and N-terminal pro B-type natriuretic peptide.

BACKGROUND AND AIMS: Myotonic dystrophy type 1 (DM1) and type 2 (DM2) are dominant inherited muscular dystrophies with multiple systemic involvement, often producing cardiac injury. This study sought to determine the clinical significance of elevated high sensitivity cardiac troponin T and I (hs-cTnT and hs-cTnI), and N-terminal pro B-type natriuretic peptide (NT-pro-BNP) in this population. METHODS: Sixty DM patients (35 men and 25 women; mean age: 45.1 years, range: 12-73 years) underwent clinical cardiac investigations and measurements of serum hs-cTnT, hs-cTnI, creatine kinase (CK), and NT-proBNP. Left ventricular (LV) ejection fraction (EF) was assessed by echocardiography. RESULTS: Genetic analysis revealed that 46 of the 60 patients were DM1, and 14 DM2. Blood measurements showed persistent elevation of hs-cTnT and CK in 55/60 DM patients (91.73%). In contrast, hs-cTnI values were persistently normal throughout the study. Only 2 patients showed an EF <50%, being the overall range of this population between 40% and 79%. We found ECG abnormalities in 19 patients. Of these patients, 13 showed first or second-degree atrio ventricular (AV) blocks (PR interval ≥ 200 ms), 4 showed a left bundle branch block (LBBB) prolonged (QRS duration ≥120 ms), and 2 had an incomplete bundle branch block (QRS duration between 110 and 119 ms). After excluding patients with EF <50%, NT-pro-BNP measurement > 125 pg/mL was an independent predictor of ECG abnormalities. CONCLUSIONS: NT-pro-BNP levels may be considered to be used clinically to identify DM patients at increased risk of developing myocardial conduction abnormalities.

High-sensitive cardiac troponin T (hs-cTnT) assay as serum biomarker to predict cardiac risk in myotonic dystrophy: A case-control study.

BACKGROUND: Myotonic dystrophy (DM) is a genetic disorder caused by nucleotide repeats expansion. Sudden death represents the main cause of mortality in DM patients. Here, we investigated the relationship between serum cardiac biomarkers with clinical parameters in DM patients. METHODS: Case-control study included 59 DM patients and 22 healthy controls. An additional group of 62 controls with similar cardiac defects to DM were enrolled. RESULTS: NT-proBNP, hs-cTnT and CK levels were significantly increased in DM patients compared to healthy subjects (p=0.0008, p<0.0001, p<0.0001). Also, hs-cTnT levels were significantly higher in DM compared to control group with cardiac defects (p=0.0003). Positive correlation was found between hs-cTnT and hs-cTnI in both DM patients and controls (p=0.019, p=0.002). Independently from the age, the risk of DM disease was positively related to an increase in hs-cTnT (p=0.03). On the contrary, the risk of DM was not related to hs-cTnI, but was evidenced a role of PR interval (p=0.03) and CK (p=0.08). CONCLUSIONS: The levels of hs-cTnT were significantly higher in DM patients. Analysis, with anti-cTnT, shows that this increase might be linked to heart problems. This last finding suggests that hs-cTnT might represent a helpful serum biomarker to "predict" cardiac risk in DM disease.