Growth Differentiation Factor 15 and the Subsequent Risk of Atrial Fibrillation: The Atherosclerosis Risk in Communities Study

Proteomic analysis of plasma proteins from patients with cardiac rupture after acute myocardial infarction using TMT-based quantitative proteomics approach

BACKGROUND

Cardiac rupture (CR) is a rare but catastrophic mechanical complication of acute myocardial infarction (AMI) that seriously threatens human health. However, the reliable biomarkers for clinical diagnosis and the underlying signaling pathways insights of CR has yet to be elucidated.

METHODS

In the present study, a quantitative approach with tandem mass tag (TMT) labeling and liquid chromatography-tandem mass spectrometry was used to characterize the differential protein expression profiles of patients with CR. Plasma samples were collected from patients with CR (n = 37), patients with AMI (n = 47), and healthy controls (n = 47). Candidate proteins were selected for validation by multiple reaction monitoring (MRM) and enzyme-linked immunosorbent assay (ELISA).

RESULTS

In total, 1208 proteins were quantified and 958 differentially expressed proteins (DEPs) were identified. The difference in the expression levels of the DEPs was more noticeable between the CR and Con groups than between the AMI and Con groups. Bioinformatics analysis showed most of the DEPs to be involved in numerous crucial biological processes and signaling pathways, such as RNA transport, ribosome, proteasome, and protein processing in the endoplasmic reticulum, as well as necroptosis and leukocyte transendothelial migration, which might play essential roles in the complex pathological processes associated with CR. MRM analysis confirmed the accuracy of the proteomic analysis results. Four proteins i.e., C-reactive protein (CRP), heat shock protein beta-1 (HSPB1), vinculin (VINC) and growth/differentiation factor 15 (GDF15), were further validated via ELISA. By receiver operating characteristic (ROC) analysis, combinations of these four proteins distinguished CR patients from AMI patients with a high area under the curve (AUC) value (0.895, 95% CI, 0.802-0.988, p < 0.001).

CONCLUSIONS

Our study highlights the value of comprehensive proteomic characterization for identifying plasma proteome changes in patients with CR. This pilot study could serve as a valid foundation and initiation point for elucidation of the mechanisms of CR, which might aid in identifying effective diagnostic biomarkers in the future.

Prediction of incident atrial fibrillation with cardiac biomarkers and left atrial volumes

OBJECTIVE

Atrial fibrillation is a common arrhythmia associated with risk of stroke, heart failure and death. We aimed to elucidate the associations of cardiac biomarkers, echocardiographic left atrial volumetric indices and risk of prevalent and incident atrial fibrillation in the general population.

METHODS

We assessed cardiac troponin T (cTnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), growth differentiation factor 15 (GDF-15), maximum (LAVi_max) and minimum (LAVi_min) indexed left atrial volumes and left atrial emptying fraction (LAEF) in subjects born in 1950 participating in the prospective observational cohort, Akershus Cardiac Examination 1950 Study. The Cohorts for Heart and Ageing Research in Genomic Epidemiology for Atrial Fibrillation risk score and sex was used to adjust for residual risk of atrial fibrillation.

RESULTS

Out of 3487 subjects, 157 (4.5%) had prevalent and 123 (3.5%) had incident atrial fibrillation. Echocardiographic left atrial volumes and cardiac biomarkers associated with prevalent atrial fibrillation, but GDF-15 was non-significant in adjusted analysis. Incident atrial fibrillation was predicted by LAVi_max (adjusted HR 1.51, 95% CI 1.30 to 1.75), LAVi_min (adjusted HR 1.52, 95% CI 1.35 to 1.72), LAEF (adjusted HR 1.24, 95% CI 1.04 to 1.48) and NT-proBNP (adjusted HR 1.57, 95% CI 1.32 to 1.85). cTnT and NT-proBNP provided incremental prognostic information to left atrial volumes, but GDF-15 demonstrated no prognostic value for incident atrial fibrillation.

CONCLUSIONS

In the general population, echocardiographic left atrial volumetric indices and NT-proBNP, but not cTnT and GDF-15, associate with prevalent atrial fibrillation and with risk of incident atrial fibrillation. cTnT and NT-proBNP provide incremental prognostic information to echocardiography.