Recent Discoveries and Novel Hypotheses

Atherosclerosis is an inflammatory process that selectively affects arteries and is highly prevalent in both women and men. Thrombo-occlusive complications of atherosclerosis, including stroke and myocardial infarction, are major causes of morbidity and mortality. Senescence of the arterial tree is a biological process that follows a natural course that can be accelerated by the combined injury of multiple risk factors. A repair capacity that is intrinsic to the organism can counteract the natural timeand risk factor– dependent obsolescence of arteries. The failure of this repair process is intimately linked to atherosclerotic inflammation and lesion formation. Recruitment and targeting of bone marrow–derived progenitor vascular cells, and probably vascular progenitors originating in other tissues, that have an intrinsic capacity for repair of the vascular wall represent a promising area for research and development. This review focuses on recent discoveries relevant to vascular progenitor cells and others that are likely to influence atherosclerosis research. It highlights the exciting recent findings that demonstrate the vital role of vascular progenitor cells in the homeostasis of the vessel wall and the mitigation of atherosclerosis. In the context of atherosclerosis, this review also discusses the relevance of this paradigm to pharmacological treatment of atherosclerosis and the process of aging.