Incorporation of α2-Plasmin Inhibitor into Fibrin Clots and Its Association with the Clinical Outcome of Acute Ischemic Stroke Patients

Diagnostic value and clinical significance of lncRNA LINC01123 combined with fibrinogen in acute cerebral infarction

OBJECTIVE

To explore the diagnostic value and clinical significance of lncRNA LINC01123 (LINC01123) binding fibrinogen in acute cerebral infarction (ACI) by evaluating the expression and potential molecular mechanism of LINC01123 in patients with acute cerebral infarction.

METHODS

The clinical data of all the volunteers were collected. The level of serum LINC01123 in ACI patients was detected by RT-qPCR. The relationship between LINC01123 and fibrinogen was studied via Pearson's correlation analysis. ROC curve was used to evaluate the diagnostic value of LINC01123 and fibrinogen for ACI. The risk factors of ACI were investigated by Binary Logistic regression analysis. And the targeting relationship between LINC01123 and downstream miR-361-3p was verified through luciferase activity assay.

RESULTS

Serum LINC01123 and fibrinogen levels were upregulated in ACI patients compared with healthy controls (P < 0.001), and there was a positive correlation between them (r = 0.6537, P < 0.001). In predicting the occurrence of ACI, LINC01123 and fibrinogen have high diagnostic value, and the AUC of combined diagnosis was 0.961, and the sensitivity and specificity (92.54%, 85.82%) were more significant. Meanwhile, LINC01123 and fibrinogen were confirmed to be independent risk factors for ACI (P < 0.0001). Mechanistically, miR-361-3p is the target of LINC01123. The expression of miR-361-3p was low in the serum of ACI patients, which was negatively correlated with the LINC01123 expression (r = -0.6885, P < 0.0001).

CONCLUSION

LINC01123 combined with fibrinogen may have important reference value in the diagnosis of ACI as serum markers, which may become clinical indicators to predict the occurrence of ACI.

Role of factor XIII in ischemic stroke: a key molecule promoting thrombus stabilization and resistance to lysis

BACKGROUND

Active coagulation factor XIII (FXIII) catalyzing crosslinking of fibrin and other hemostatic factors plays a key role in clot stability and lysis.

OBJECTIVES

To evaluate the effect of FXIII inhibition in a mouse model of ischemic stroke (IS) and the role of activated FXIII (FXIIIa) in clot formation and lysis in patients with IS.

METHODS

A ferric chloride IS murine model was performed before and after administration of a FXIIIa inhibitor (FXIIIinh). Thromboelastometry in human and mice blood was used to evaluate thrombus stiffness and lysis with FXIIIinh. FXIIIa-dependent fibrin crosslinking and lysis with fibrinolytic drugs (tissue plasminogen activator and tenecteplase) were studied on fibrin plates and on thrombi and clotted plasma of patients with IS. Finally, circulating and thrombus FXIIIa were measured in 85 patients with IS.

RESULTS

FXIIIinh administration before stroke induction reduced infarct size, α2-antiplasmin (α2AP) crosslinking, and local microthrombosis, improving motor coordination and fibrinolysis without intracranial bleeds (24 hours). Interestingly, FXIII blockade after stroke also reduced brain damage and neurologic deficit. Thromboelastometry in human/mice blood with FXIIIinh showed delayed clot formation, reduced clot firmness, and shortened tissue plasminogen activator lysis time. FXIIIa fibrin crosslinking increased fibrin density and lysis resistance, which increased further after α2AP addition. FXIIIinh enhanced ex vivo lysis in stroke thrombi and fibrin plates. In patients with IS, thrombus FXIII and α2AP were associated with inflammatory and hemostatic components, and plasma FXIIIa correlated with thrombus α2AP and fibrin.

CONCLUSION

Our results suggest a key role of FXIIIa in thrombus stabilization, α2AP crosslinking, and lysis resistance, with a protective effect of FXIIIinh in an IS experimental model.

Factor XIII in the Acute Care Setting and Its Relevance in Obstetric Bleeding

Background

Major hemorrhage is one of the main causes of preventable mortality in either severe trauma, high-risk surgical patient, or the obstetric population. As underlined by the cell-based coagulation model, a resistant and stable clot is essential to prevent or to stop an ongoing bleeding. Coagulation factor XIII (FXIII) stabilizes the newly formed clot by cross-linking the fibrin monomers into a three-dimensional network and by impeding fibrinolysis. Thus, FXIII is an essential coagulation factor in the acutely bleeding patient.

Summary

Acquired FXIII deficiency is much more common than the inherited form. On the basis of acute tissue injury which leads to major bleeding, acquired FXIII deficiency is traditionally considered to be secondary to consumption. However, recent evidence in the field of obstetrics and high-risk surgery suggests that it might be an associated factor rather than a consequence of the bleeding, which would mean that early replacement of FXIII could potentially improve outcomes. However, FXIII measurement is not universally available. Assessing FXIII through viscoelastic assays seems feasible, though likely it is not yet accurate. Moreover, the target population at risk and the aimed FXIII level required to achieve hemostasis in each condition are yet to be defined.

Key Messages

FXIII should be assessed and replaced if necessary in the acutely bleeding patient. We recommend FXIII to be included in an escalating scheme of hemostatic therapies in the acute care setting.