The role of apoptosis in vascular disease

Abstract

Normal arteries are characterized by a low turnover of endothelial (EC) and smooth muscle cells (SMC). Different mechanisms protect the EC and SMC against apoptosis in the normal artery. In hypertension, SMC replication is increased but this is not counterbalanced by increased apoptosis, resulting in thickening of the media of arteries and arterioles. The significance of apoptosis in atherosclerosis depends on the stage of the plaque, localization and the cell types involved. Both macrophages and SMC undergo apoptosis in atherosclerotic plaques. Apoptosis of macrophages is mainly present in regions showing signs of DNA synthesis/repair. SMC apoptosis is mainly present in less cellular regions and is not associated with DNA synthesis/repair. Even in the early stages of atherosclerosis SMC become susceptible to apoptosis since they increase different pro‐apoptotic factors. Moreover, recent data indicate that SMC may be killed by activated macrophages. The loss of the SMC can be detrimental for plaque stability since most of the interstitial collagen fibres, which are important for the tensile strength of the fibrous cap, are produced by SMC. Apoptosis of macrophages could be beneficial for plaque stability if apoptotic bodies were removed. Apoptotic cells that are not scavenged in the plaque activate thrombin, which could further induce intraplaque thrombosis. It can be concluded that apoptosis in primary atherosclerosis is detrimental since it could lead to plaque rupture and thrombosis. Recent data of our group indicate that apoptosis decreased after lipid lowering which could be important in the understanding of the cell biology of plaque stabilization. Copyright © 2000 John Wiley & Sons, Ltd.

High Glucose Inhibits Apoptosis Induced by Serum Deprivation in Vascular Smooth Muscle Cells via Upregulation of Bcl-2 and Bcl-xl

“…The significance of apoptosis in atherosclerosis appears to depend on the stage of the plaque, localization, and cell types involved (41). Glucose-induced suppression of apoptosis appears to be of particular importance in the initial events of vascular injury and thickening of the media of the vessels.…”

A tale of two mitochondrial channels, MAC and PTP, in apoptosis

“…Although apoptosis is an essential process for all multicellular organisms, it is also involved or associated with a wide range of diseases and pathological conditions [92][93][94][95][96][97]. This has made apoptosis an attractive potential target for treatment of various diseases.…”

Role of macrophage and smooth muscle cell apoptosis in association with oxidized low-density lipoprotein in the atherosclerotic development

“…[6][7][8][9] The pathophysiological roles of apoptosis in atherosclerosis have been discussed in conjunction with cell distribution and type as well as with plaque stabilization, plaque rupture, and regression of thickened arterial walls. 7,[10][11][12][13] Apoptotic cells are usually identified by morphological observation using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL). 5 However, single-stranded DNA monoclonal antibody developed recently is further sensitive enough to detect from the beginning of apoptosis.…”