Influence of variation in fat composition on haemostatic variables

Area of Science:

• Cardiovascular Science
• Nutrition Science
• Hemostasis and Thrombosis

Background:

• Hypercholesterolemia is linked to increased platelet aggregation.
• Saturated fatty acids' effects on platelet function are not fully understood.
• n-3 fatty acids alter platelet and endothelial cell fatty acid composition.

Purpose of the Study:

• To investigate the impact of n-3 fatty acids on platelet function and hemostasis.
• To examine the relationship between dietary fat type and fibrinolytic activity.
• To assess the effect of n-3 fatty acids on factor VII coagulant activity (FVIIc).

Main Methods:

• Analysis of platelet and endothelial cell fatty acid composition (arachidonic acid, EPA, DHA).
• Measurement of template bleeding time.
• Assessment of fibrinolytic markers (PAI-1, tPA, fibrinogen) and FVIIc.
• Evaluation of postprandial factor VII activation.

Main Results:

• n-3 fatty acids decrease platelet arachidonic acid and increase EPA/DHA, prolonging bleeding time.
• This shift reduces thromboxane A2 and increases anti-aggregatory prostacyclins.
• No significant effect of fat type on fibrinolysis markers was observed.
• n-3 fatty acids did not decrease FVIIc, despite hypotriglyceridemic effects.
• Oleic acid is a potent activator of postprandial FVII, dose-dependently.

Conclusions:

• n-3 fatty acids modify platelet function, potentially reducing thrombotic risk.
• Dietary fat type has limited influence on fibrinolysis.
• High fat intake, particularly with potent activators like oleic acid, may pose a prothrombotic risk in older adults.