Platelet activation plays a key role in
atherogenesis and
atherothrombosis. Biochemical evidence of increased platelet activation in vivo can be reliably obtained through non-invasive measurement of
thromboxane metabolite (TXM) excretion. Persistent biosynthesis of TXA2 has been associated with several ageing-related diseases, including acute and chronic cardio-
cerebrovascular diseases and cardiovascular risk factors, such as cigarette smoking, type 1 and
type 2 diabetes mellitus,
obesity,
hypercholesterolemia,
hyperhomocysteinemia,
hypertension,
chronic kidney disease, chronic inflammatory diseases. Given the systemic nature of TX excretion, involving predominantly platelet but also extraplatelet sources, urinary TXM may reflect either platelet
cyclooxygenase-1 (COX-1)-dependent TX generation or COX-2-dependent biosynthesis by inflammatory cells and/or platelets, or a combination of the two, especially in clinical settings characterized by low-grade
inflammation or enhanced platelet turnover. Although urinary
11-dehydro-TXB2 levels are largely suppressed with low-dose
aspirin, incomplete TXM suppression by
aspirin predicts the future risk of vascular events and death in high-risk patients and may identify individuals who might benefit from treatments that more effectively block in vivo TX production or activity. Several disease-modifying agents, including lifestyle intervention,
antidiabetic drugs and
antiplatelet agents besides
aspirin have been shown to reduce TX biosynthesis. Taken together, these aspects may contribute to the development of promising mechanism-based therapeutic strategies to reduce the progression of
atherothrombosis. We intended to critically review current knowledge on both the pathophysiological significance of urinary TXM excretion in clinical settings related to ageing and
atherothrombosis, as well as its prognostic value as a
biomarker of vascular events.