Characterization of Carotid Smooth Muscle Cells during Phenotypic Transition

Abstract

Vascular smooth muscle cells (VSMCs) are central players in carotid atherosclerosis plaque development. Although the precise mechanisms involved in plaque destabilization are not completely understood, it is known that VSMC proliferation and migration participate in plaque stabilization. In this study, we analyzed expression patterns of genes involved in carotid atherosclerosis development (e.g., transcription factors of regulation of SMC genes) of VSMCs located inside or outside the plaque lesion that may give clues about changes in phenotypic plasticity during atherosclerosis. VSMCs were isolated from 39 carotid plaques extracted from symptomatic and asymptomatic patients by endarterectomy. Specific biomarker expression, related with VSMC phenotype, was analyzed by qPCR, western immunoblot, and confocal microscopy. MYH11, CNN1, SRF, MKL2, and CALD1 were significantly underexpressed in VSMCs from plaques compared with VSMCs from a macroscopically intact (MIT) region, while SPP1, KLF4, MAPLC3B, CD68, and LGALS3 were found significantly upregulated in plaque VSMCs versus MIT VSMCs. The gene expression pattern of arterial VSMCs from a healthy donor treated with 7-ketocholesterol showed high similarity with the expression pattern of carotid plaque VSMCs. Our results indicate that VSMCs isolated from plaque show a typical SMC dedifferentiated phenotype with macrophage-like features compared with VSMCs isolated from a MIT region of the carotid artery. Additionally, MYH11, KLF5, and SPP1 expression patterns were found to be associated with symptomatology of human carotid atherosclerosis.

Downregulation of miR‑142‑5p inhibits human aortic smooth muscle cell proliferation and migration by targeting MKL2

“…Furthermore, another study revealed that MKl2 functioned as a pro-migratory gene in VSMcs (34). in the present study, MKl2 was found to be underexpressed in the serum of patients with aS compared with that of healthy volunteers, which was consistent with the findings of a previous study (35). In addition, via gain-of-function and loss-of-function approaches, transfection with miR-142-5p inhibitor significantly increased the mRNA and protein expression level of MKL2 in HASMCs; however, transfection with MKl2-sirna resulted in a decreased MKL2 expression.…”

Targeting DNA Methylation Depletes Uterine Leiomyoma Stem Cell–enriched Population by Stimulating Their Differentiation

“…Consistent with previous reports showing that DNA hypomethylating agents can remove the epigenetic “brake” and allow stem cells to undergo differentiation ( 17 ), we found that the DNA methylation inhibitor 5′-Aza not only upregulated expression of genes imperative for differentiation but also functionally depleted the LSC population and inhibited its colony formation ( 20 , 54 ). 5′-Aza-induced LSC differentiation was supported by the observation that 5′-Aza treatment significantly increased the expression of markers of fully differentiated smooth muscle cells, such as MYH11 ( 44 ). Notably, we found that RU486 pretreatment did not significantly affect the LM cells’ colony-forming activity and was less efficient in inhibiting LM regeneration compared with 5′-Aza treatment, suggesting that LSC deficient in steroid hormone receptors may remain quiescent, constituting a small population of cells resistant to RU486 treatment.…”

“…TIMP3, tissue inhibitor of metalloproteinase 3, regulates extracellular matrix at the tumor–stromal interface ( 39 ) and is critical in driving differentiation and decreasing tumorigenesis in the mammary gland and muscle tissues ( 40 , 41 ). The ROR2 pathway plays complex roles in stem cell function and carcinogenesis ( 42 , 43 ), and MYH11 is a marker of fully differentiated smooth muscle cells ( 44 ).…”

Liraglutide treatment improves endothelial function in the Ldlr−/− mouse model of atherosclerosis and affects genes involved in vascular remodelling and inflammation

“…These analyses, however, confirmed that the two genes were heterogeneously expressed throughout the vessel and lesion, with the majority of Cnn1 expressed in the wall as expected, as it is a VSMC marker and this is where most VSMC are located. 16 Cnn1-expressing cells were also found in the cap of the plaque, showing the involvement of VSMC in cap formation. 17 Timp2 was dispersed throughout the whole artery and both present in the wall and the plaque with a tendency towards a higher expression within the plaque itself ( Figure 6C-E).…”