Visceral Adipose Tissue and Atherosclerosis

Obesity is a risk factor for complications of atherosclerotic vascular disease such as myocardial infarction and stroke. Recent studies have demonstrated that the vascular risk associated with obesity is correlated particularly with visceral adiposity. These clinical observations indicate that various adipose tissue depots may have differential effects on vascular risk. Cellular constituents of adipose tissue secrete cytokines and chemokines that may affect vascular disease. Visceral fat has been demonstrated to express more inflammatory cytokines than subcutaneous fat in obese states. The adipose tissue secretory profile may reflect the influx of macrophages that has been shown to occur with expansion of fat stores. This macrophage infiltration may lead to a chronic low grade, systemic, inflammatory state. Since circulating markers of inflammation are associated with cardiovascular events, the inflammation triggered by adipose tissue may contribute to increased vascular disease. While the vasculopathic effects of visceral obesity may be best treated by weight loss, long term weight loss is difficult to achieve, even with currently available pharmacotherapies. Therapies that target macrophage accumulation in fat or the adipocyte expression profile may be potentially beneficial in reducing the vascular risk associated with obesity. Further characterization of the factors responsible for promoting atherosclerosis in the setting of visceral obesity may lead to new targets for the prevention of atherosclerosis.