Summary
The homozygous factorV Leiden mutation is associated with enhanced venous thrombotic
risk. Obesity is a major risk factor for development of thrombotic cardiovascular
disease. It was the objective of this study to investigate whether obesity affects
the thrombotic risk associated with the mutation. Male mice with homozygous factor
V Leiden mutation (Arg 504 to Gln) (FVQ/Q) and corresponding wild-type (WT) mice were
kept on a standard fat diet (SFD) or high fat diet (HFD) for 14 weeks, and femoral
artery thrombosis was induced by FeCl3 treatment. As compared to SFD, HFD feeding for 14 weeks resulted in significantly
higher body weight and fat mass associated with adipocyte hypertrophy, which were,
however, similar for both geno types. In the FeCl3-induced arterial thrombosis model, FVQ/Q mice kept on SFD had a 40% shorter occlusion
time (p = 0.015) and 40% lower blood flow (p = 0.03), as compared to WT mice. However,
on HFD the occlusion time and blood flow were not significantly different for both
genotypes. This finding could not be explained by differential changes of coagulation
factors in either genotype fed on SFD or HFD. In conclusion, on SFD, but not on HFD,
the factorV Leiden mutation is associated with enhanced thrombotic tendency after
FeCl3 injury of the femoral artery, suggesting that in this model obesity rescues the increased
thrombotic risk associated with the factorV Leiden mutation.
Keywords
Factor V Leiden - obesity - thrombosis