Exploring the Relationship Between Thymosin β4 Protein and First Myocardial Infarction on the Basis of Proteomics.

BACKGROUND: Plasma protein alterations may occur in patients with acute myocardial infarction (AMI). In this study, we investigated the plasma proteomics of patients with first-onset AMI to identify a novel diagnostic target for myocardial infarction. METHODS: Using a case-control design, we recruited 6 patients with first-onset AMI and 6 age- and sex-matched healthy controls. Mass spectrometry was used to analyze their plasma proteomics. Additionally, we enrolled 156 patients with AMI and 232 healthy individuals to validate the differentially expressed proteins using ELISA. RESULTS: A total of 58 differentially expressed proteins were identified between the 2 groups (<0.05, fold change ≥2 or ≤1/2), including 36 upregulated and 22 downregulated proteins. Notably, we discovered a clinically significant protein, thymosin β4 (TMSB4), which was subsequently validated by ELISA. Plasma TMSB4 levels were significantly elevated in patients with first-onset AMI compared with the control group (1093 [701-1608] ng/mL versus 421 [245-658] ng/mL;<0.001). Univariate and multivariate logistic regression analyses indicated that TMSB4 is a risk factor for first-onset AMI. The receiver operating characteristic curve yielded an area under the curve value of 0.849, with an optimal cutoff of 682 ng/mL, sensitivity of 0.808, and specificity of 0.793. A robust correlation was observed between TMSB4 and cardiac troponin I (=0.9044,<0.0001), and the κ test yielded a moderate concordance value (κ=0.590 [95% CI, 0.509-0.671];<0.001). CONCLUSIONS: TMSB4 holds diagnostic value for first-onset myocardial infarction and may therefore be considered a potential diagnostic marker for infarction. REGISTRATION: URL: https://www.chictr.org.cn/; unique identifier: ChiCTR2300078144.