Identification of Monocyte-Associated Genes Related to the Instability of Atherosclerosis Plaque

Abstract

Background. Atherosclerotic plaque instability is a common cause of stroke and ischemic infarction, and identification of monocyte-associated genes has become a prominent feature in cardiovascular research as a contributing/predictive marker. Methods. Whole genome sequencing data were downloaded from GSE159677, GSE41571, GSE120521, and GSE118481. Single-cell sequencing data analysis was conducted to cluster molecular subtypes of atherosclerotic plaques and identify specific genes. Differentially expressed genes (DEGs) between normal subjects and patients with unstable atheromatous plaques were screened. Weighted gene coexpression network analysis (WGCNA) was performed to find key module genes. In addition, GO and KEGG enrichment analyses explored potential biological signaling pathways to generate protein interaction (PPI) networks. GSEA and GSVA demonstrated activations in plaque instability subtypes. Results. 239 monocyte-associated genes were identified based on bulk and single-cell RNA-sequencing, followed by the recognition of 1221 atherosclerotic plaque-associated DEGs from the pooled matrix. GO and KEGG analyses suggested that DEGs might be related to inflammation response and the PI3K-Akt signaling pathway. Eight no-grey modules were obtained through WGCNA analysis, and the turquoise module has the highest correlation with unstable plaque ( R 2 = 0.40 ), which contained 1323 module genes. After fetching the intersecting genes, CXCL3, FPR1, GK, and LST1 were obtained that were significantly associated with plaque instability, which had an intense specific interaction. Monocyte-associated genes associated with atherosclerotic plaque instability have certain diagnostic significance and are generally overexpressed in this patient population. In addition, 11 overlapping coexpressed genes (CEG) might also activated multiple pathways regulating inflammatory responses, platelet activation, and hypoxia-inducible factors. GSVA showed that the corresponding pathways were significantly activated in high expression samples. Conclusions. Overexpression of CXCL3, GK, FPR1, and LST1 was advanced recognition and intervention factors for unstable plaques, which might become targets for atherosclerosis rupture prevention. We also analyzed the potential mechanisms of CEG from inflammatory and oxidative stress pathways.

Heterogeneity of macrophages in atherosclerosis revealed by single‐cell RNA sequencing

“…Additionally, there are evidence that the genes Alox5 , Ncf1 , Mmp9 , and Ncf4 associated with oxidative stress may be involved in the formation of the inflammatory core by regulating macrophage ferroptosis and lipid metabolism 76 . Pathway enrichment analysis showed that overexpression of Gk , Fpr1 , and Lst1 was advanced recognition and intervention factor for unstable plaques, which were enriched in inflammatory and oxidative stress pathways 26 …”

“…76 Pathway enrichment analysis showed that overexpression of Gk, Fpr1, and Lst1 was advanced recognition and intervention factor for unstable plaques, which were enriched in inflammatory and oxidative stress pathways. 26…”

“…23,24 Glycolysis and fatty acid oxidation can also play key roles in determining function through differential metabolic activation. 25,26 Macrophages also release oxidized phospholipids, contributing to inflammation, and leading to leukocyte adhesion molecules being expressed on endothelial cells (ECs). [27][28][29][30] Aside from recruitment, lesion macrophages can also be increased locally through other processes.…”

“…Two opposing phenotypic states have been described in classical macrophage polarization models: the pro‐inflammatory M1 macrophage plays a role induced by bacterial lipopolysaccharide 21,22 and/or interferon‐gamma, and the anti‐inflammatory M2 macrophages that can be activated by interleukin 4 23,24 . Glycolysis and fatty acid oxidation can also play key roles in determining function through differential metabolic activation 25,26 . Macrophages also release oxidized phospholipids, contributing to inflammation, and leading to leukocyte adhesion molecules being expressed on endothelial cells (ECs) 27–30 .…”

Porphyromonas gingivalis regulates atherosclerosis through an immune pathway

“…VSMCs and endothelial cells (ECs) in the core of human arterial AS lesions were found to drive cellular transdifferentiation through multiple genes, whereas VSMCs and ECs in the adjacent zone were involved in immune cell recruitment through C3 and MHC II molecules, respectively ( 14 ). More in-depth studies using single-cell sequencing pointed out that DHRS9 in macrophages is a key factor in AS formation ( 15 ), and CXCL3, GK, FPR1, and LST1 in monocytes are closely associated with plaque instability ( 16 ). The application of single-cell sequencing technology has deepened the understanding of cellular heterogeneity in AS lesions, and provided an important theoretical basis for further investigation of AS pathogenesis and the development of targeted therapeutic drugs.…”