Summary
Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), together with
extrinsic coagulation pathway activation and increased oxidative stress (SOX) have
all been implicated as important factors in atherosclerosis and vascular remodelling.
The aim of the present study was to investigate whether the MMPs/TIMPs system is associated
with activation of the extrinsic coagulation pathway in conditions of increased SOX
in hemodialysis (HD) patients. In HD patients, with and without cardiovascular disease
(CVD), and in controls, we compared pre-dialysis levels of MMP-2, MMP-9,TIMP-1,TIMP-2;
the markers of extrinsic coagulation pathway-tissue factor (TF) and its inhibitor
(TFPI), prothrombin fragment F1+2 (F1+2); a marker of SOX-Cu/Zn superoxide dismutase
(Cu/Zn SOD) and a surrogate of atherosclerotic disease-intima media thickness (IMT).
Hemodialysis patients, particularly those with CVD, showed a significant increase
in values of MMP-2/TIMPs, markers of the extrinsic coagulation pathway, Cu/Zn SOD
and IMT as compared to controls. The markers of coagulation activation positively
correlated with the MMP-2/TIMPs system, whereas they did not correlate with MMP-9.
In addition, both MMP-2/TIMPs as well as extrinsic coagulation parameters were related
to the prevalence of increased SOX, IMT and CVD. Multiple stepwise regression analysis
showed that low TIMP-2 followed by increased Cu/Zn SOD and MMP-2 levels independently
and significantly predicted elevated IMT on maintenance HD patients. In conclusion,
our data suggest that the MMP-2/TIMPs system and an activated extrinsic coagulation
pathway could cooperate in conditions of elevated SOX and could influence arterial
remodeling resulting in the presence of CVD in haemodialysis patients.
Keywords Atherosclerosis - coagulation activation - MMPs/TIMPs system - hemodialysis - oxidative
stress