Zinc alters fibrin ultrastructure.

Area of Science:

• Biochemistry
• Hematology
• Biophysics

Background:

• Fibrin gelation is a critical process in hemostasis.
• The role of divalent cations, particularly zinc (Zn(II)), in modulating fibrin structure is not fully understood.
• Understanding fibrin structure is crucial for developing effective anticoagulants and treatments for bleeding disorders.

Purpose of the Study:

• To investigate the effect of zinc (Zn(II)) on fibrin gelation kinetics and clot structure.
• To quantify the changes in fibrin fiber thickness and composition induced by Zn(II).
• To elucidate the mechanism by which Zn(II) modulates fibrin ultrastructure.

Main Methods:

• Turbidimetric studies were employed to measure fibrin clotting time (CT) and turbidity.
• Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were used to visualize fibrin fiber morphology.
• Fibrinogen concentration and Zn(II) levels were systematically varied.

Main Results:

• Zn(II) was found to accelerate fibrin gelation, decreasing clotting time.
• Increased Zn(II) concentrations led to higher maximal fibrin clot turbidity, indicating coarser fibers.
• Electron microscopy confirmed that Zn(II) significantly increases fibrin fiber diameter, with fiber thickness correlating to Zn(II) levels.
• Fibrin strands were composed of 2 to 40 monomeric fibrin molecules depending on Zn(II) concentration.

Conclusions:

• Zinc (Zn(II)) drastically modulates fibrin ultrastructure at physiologically relevant levels.
• Zn(II) promotes the formation of thicker fibrin fibers, resulting in a coarser gel network.
• These findings have implications for understanding thrombosis and developing novel therapeutic strategies.