Multifaceted roles of Meg3 in cellular senescence and atherosclerosis

Authors

Xiao Cheng, University of Nebraska - Lincoln
Mohamed Sham Shihabudeen Haider Ali, University of Nebraska - Lincoln
Vijaya Bhaskar Baki, University of Nebraska - Lincoln
Matthew Moran, University of Nebraska - Lincoln
Huabo Su, Augusta University
Xinghui Sun, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

5-13-2024

Citation

Atherosclerosis. 2024 May ; 392: 117506. doi:10.1016/j.atherosclerosis.2024.117506.

Comments

HHS Public Access.

Abstract

Background and aims: Long noncoding RNAs are involved in the pathogenesis of atherosclerosis. As long non-coding RNAs maternally expressed gene 3 (Meg3) prevents cellular senescence of hepatic vascular endothelium and obesity-induced insulin resistance, we decided to examine its role in cellular senescence and atherosclerosis.

Methods and Results: By analyzing our data and human and mouse data from the Gene Expression Omnibus database, we found that Meg3 expression was reduced in humans and mice with cardiovascular disease, indicating its potential role in atherosclerosis. In Ldlr^−/− mice fed a Western diet for 12 weeks, Meg3 silencing by chemically modified antisense oligonucleotides attenuated the formation of atherosclerotic lesions by 34.9% and 20.1% in male and female mice, respectively, revealed by en-face Oil Red O staining, which did not correlate with changes in plasma lipid profiles. Real-time quantitative PCR analysis of cellular senescence markers p21 and p16 revealed that Meg3 deficiency aggravates hepatic cellular senescence but not cellular senescence at aortic roots. Human Meg3 transgenic mice were generated to examine the role of Meg3 gain-of-function in the development of atherosclerosis induced by PCSK9 overexpression. Meg3 overexpression promotes atherosclerotic lesion formation by 29.2% in Meg3 knock-in mice independent of its effects on lipid profiles. Meg3 overexpression inhibits hepatic cellular senescence, while it promotes aortic cellular senescence likely by impairing mitochondrial function and delaying cell cycle progression.

Conclusions: Our data demonstrate that Meg3 promotes the formation of atherosclerotic lesions independent of its effects on plasma lipid profiles. In addition, Meg3 regulates cellular senescence in a tissue-specific manner during atherosclerosis. Thus, we demonstrated that Meg3 has multifaceted roles in cellular senescence and atherosclerosis.