Impaired fibrinolysis in angiographically documented coronary artery disease

Identification of Genes and miRNAs Associated with TAFI-Related Thrombosis: An in Silico Study

Thrombin-Activatable Fibrinolysis Inhibitor (TAFI) is a carboxypeptidase B-like proenzyme encoded by the CPB2 gene. After thrombin activation, TAFI downregulates fibrinolysis, thus linking the latter with coagulation. TAFI has been shown to play a role in venous and arterial thrombotic diseases, yet, data regarding the molecular mechanisms underlying its function have been conflicting. In this study, we focused on the prediction and functional enrichment analysis (FEA) of the TAFI interaction network and the microRNAs (miRNAs) targeting the members of this network in an attempt to identify novel components and pathways of TAFI-related thrombosis. To this end, we used nine bioinformatics software tools. We found that the TAFI interactome consists of 28 unique genes mainly involved in hemostasis. Twenty-four miRNAs were predicted to target these genes. Co-annotation analysis of the predicted interactors with respect to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and transcription factors (TFs) pointed to the complement and coagulation cascades as well as neutrophil extracellular trap formation. Cancer, stroke, and intracranial aneurysm were among the top 20 significant diseases related to the identified miRNAs. We reason that the predicted biomolecules should be further studied in the context of TAFI-related thrombosis.

A Case-Control Study of the Dose-Response Relationship Between Thrombin Activatable Fibrinolysis Inhibitor and Acute Myocardial Infarction

Background

Acute myocardial infarction (AMI) is considered an acute coronary syndrome (ACS), which is caused by the death of myocardial cells after prolonged ischemia, and there is a high risk of sudden death during AMI. Therefore, the purpose of this study is to explore the relationship between thrombin activatable fibrinolysis inhibitor (TAFI) and AMI and provide evidence for their association and potentially the prevention of AMI.

Methods

There were 228 subjects included in this retrospective study, which included 78 AMI patients and 150 controls. The immune turbidimetry was used to measure TAFI concentration in the serum. Mann–Whitney U test was used to compare serum TAFI levels. The logistic regression analysis was used to construct a model of influencing factors of AMI. The dose-response relationship between serum TAFI level and AMI was explored by using the restricted cubic spline (RCS) functions combined with logistic regression analysis.

Results

The serum TAFI levels of the AMI group were higher than the control group’s (P = 0.003). The risk of AMI in the high-TAFI level group was 2.24 times higher than the low-TAFI level group (P = 0.007) and it was 2.74 times higher after adjustment of other risk factors (P = 0.025). According to the dose-response curve, the risk of AMI increased significantly with an increase of serum TAFI concentration (P = 0.0387).

Conclusion

Acute myocardial infarction patients had higher serum TAFI levels, and TAFI was an independent risk factor for AMI patients. Serum TAFI levels demonstrated a dose- dependent response to the risk of AMI. Our study provides evidence that TAFI could be used for risk stratification of AMI patients.

Current understanding of the pathophysiology of chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a unique form of pulmonary hypertension arising from fibrotic obliteration of major pulmonary arteries. Pro-thrombotic states, large clot burden and impaired dissolution are believed to contribute to the occurrence and progression of thrombosis after an acute pulmonary embolic event. Recent data utilizing several models have facilitated the understanding of clot resolution. This review summarizes current knowledge on pathophysiological mechanisms of major vessel occlusion in CTEPH.

Reduced thrombin activatable fibrinolysis inhibitor and enhanced proinflammatory cytokines in acute coronary syndrome

OBJECTIVE

A study was made of the changes in the serum levels of thrombin activatable fibrinolysis inhibitor (TAFI), proinflammatory cytokines and acute phase proteins in the acute stage of acute coronary syndrome (ACS), in order to explore the possibility of using TAFI as a biomarker for ACS risk assessment.

METHODS

A total of 211 patients with ACS were enrolled, and healthy subjects were used as controls. Blood samples were taken within 24h after admission. Serum TAFI levels were determined by immunoturbidimetry. Serum levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were determined by enzyme linked immunosorbent assay (ELISA). Procalcitonin (PCT) and C-reactive protein (CRP) levels were measured by gold-immunochromatographic assay.

RESULTS

Serum TAFI levels in ACS patients were significantly decreased versus the controls. The IL-1β, IL-6, TNF-α, PCT and CRP levels were markedly higher in the ACS patients than in the controls. Correlation analysis revealed a strong negative correlation between TAFI concentration and the IL-1β, IL-6, TNF-а, PCT and CRP levels in ACS patients and in controls. Multivariate logistic regression analysis suggested decreased serum TAFI to be an independent risk factor for ACS (OR 9.459; 95% CI 2.306-38.793; P=0.002). The area under the receiver operating characteristic (ROC) curve for TAFI was 0.872 (95% CI 0.787-0.909; P<0.001). The optimum TAFI cutoff point for the prediction of ACS was 24μg/ml, with a sensitivity of 75.83% and a specificity of 72.57%.

CONCLUSION

These findings suggest that TAFI can be useful as a potential biomarker for ACS risk assessment.