Lifestyle effects on hematopoiesis and atherosclerosis.

Diet, exercise, stress, and sleep are receiving attention as environmental modifiers of chronic inflammatory diseases, including atherosclerosis, the culprit condition of myocardial infarction and stroke. Accumulating data indicate that psychosocial stress and a high-fat, high-cholesterol diet aggravate cardiovascular disease, whereas regular physical activity and healthy sleeping habits help prevent it. Here, we raise the possibility that inflammation-associated leukocyte production plays a causal role in lifestyle effects on atherosclerosis progression. Specifically, we explore whether and how potent real-life disease modifiers influence hematopoiesis' molecular and cellular machinery. Lifestyle, we hypothesize, may rearrange hematopoietic topography, diverting production from the bone marrow to the periphery, thus propagating a quantitative and qualitative drift of the macrophage supply chain. These changes may involve progenitor-extrinsic and intrinsic communication nodes that connect organ systems along neuroimmune and immunometabolic axes, ultimately leading to an altered number and phenotype of lesional macrophages. We propose that, in conjunction with improved public health policy, future therapeutics could aim to modulate the quantitative and qualitative output, as well as the location, of the hematopoietic tree to decrease the risk of atherosclerosis complications.