Identification of Genes Potentially Involved in Rupture of Human Atherosclerotic Plaques

Abstract

Abstract-Although rupture of an atherosclerotic plaque is the major cause of acute vascular occlusion, the exact molecular mechanisms underlying this process are still poorly understood. In this study, we used suppression subtractive hybridization to make an inventory of genes that are differentially expressed in whole-mount human stable and ruptured plaques. Two libraries were generated, one containing 3000 clones upregulated and one containing 2000 clones downregulated in ruptured plaques. Macroarray analysis of 500 randomly chosen clones showed differential expression of 45 clones. Among the 25 clones that showed at least a 2-fold difference in expression was the gene of perilipin, upregulated in ruptured plaques, and the genes coding for fibronectin and immunoglobulin chain, which were downregulated in ruptured plaques. Reverse transcriptase-polymerase chain reaction analysis on 10 individual ruptured and 10 individual stable plaques showed a striking consistency of expression for the clones SSH6, present in 8 ruptured and 2 stable plaques, and perilipin, expressed in 8 ruptured plaques and completely absent in stable plaques.

Identification of Neutral Cholesterol Ester Hydrolase, a Key Enzyme Removing Cholesterol from Macrophages

“…Cell nuclei were counterstained with methyl green. Combined immunohistochemical staining was performed to identify the cell types expressing NCEH as described previously with minor modifications (28). NCEH was first localized by using the protocol above.…”

Lipid homeostasis and the formation of macrophage-derived foam cells in atherosclerosis

“…Perilipin was found to be expressed in foam cells adjacent to ruptured plaques but was absent in stable plaques of human atherosclerotic lesions (Faber et al, 2001). Because ADRP coats the surface of LDs of perilipin-null adipocytes (Tansey et al, 2001), it was predicted that in the absence of ADRP, perilipin could eventually take over its role in foam cells.…”

Genome-Wide Expression Studies of Atherosclerosis

“…Various screening methods have been applied to study gene expression patterns in atherosclerosis: array analysis, 10 -22,27,28 suppression subtractive hybridization (SSH), 23 …”

“…25,31 In these studies, a high proportion (33% to 55%) of differentially expressed sequences represented genes that have not yet been annotated or functionally characterized. The article by Faber et al 23 is the only one to our knowledge that reports the gene expression profile of atherosclerotic plaques with a thrombus (Table 3). In this study, SSH is used to make an inventory of genes that are differentially expressed in whole-mount stable versus thrombus-containing plaques.…”

“…In this study, SSH is used to make an inventory of genes that are differentially expressed in whole-mount stable versus thrombus-containing plaques. Several genes that had not previously been linked to atherosclerosis (including perilipin 23 and a previously unidentified gene named vasculin 46 ) were identified as being differentially expressed.…”