Overexpression of MicroRNA‐16 Alleviates Atherosclerosis by Inhibition of Inflammatory Pathways

Abstract

Background. Our previous study demonstrated that the expression of miR-16 was downregulated in the cell and animal models of atherosclerosis (AS), a main contributor to coronary artery disease (CAD). Overexpression of miR-16 inhibited the formation of foam cells by exerting anti-inflammatory roles. These findings indicated miR-16 may be an anti-atherogenic and CAD miRNA. The goal of this study was to further validate the expression of miR-16 in CAD patients and explore its therapeutic roles in an AS animal model. Methods. A total of 40 CAD patients and 40 non-CAD people were prospectively registered in our study. The AS model was established in ApoE-/- mice fed a high-fat diet. The model mice were randomly treated with miR-16 agomiR (n=10) or miR-negative control (n=10). Hematoxylin-eosin staining was conducted for histopathological examination in thoracic aorta samples. ELISA and immunohistochemistry were performed to determine the expression levels of inflammatory factors (IL-6, TNF-α, MCP-1, IL-1β, IL-10, and TGF-β). qRT-PCR and western blotting were carried out to detect the mRNA and protein expression levels of PDCD4, miR-16, and mitogen-activated protein kinase pathway-related genes. Results. Compared with the normal control, miR-16 was downregulated in the plasma and peripheral blood mononuclear cell of CAD patients, and its expression level was negatively associated with IL-6 and the severity of CAD evaluated by the Gensini score, but positively related with IL-10. Injection of miR-16 agomiR in ApoE-/- mice reduced the formation of atherosclerotic plaque and suppressed the accumulation of proinflammatory factors (IL-6, TNF-α, MCP-1, and IL-1β) in the plasma and tissues but promoted the secretion of anti-inflammatory factors (IL-10 and TGF-β). Mechanism analysis showed overexpression of miR-16 might downregulate target mRNA PDCD4 and then activate p38 and ERK1/2, but inactivate the JNK pathway. Conclusions. Our findings suggest miR-16 may be a potential diagnostic biomarker and therapeutic target for atherosclerotic CAD.

The Emerging Role of Long Non-coding RNAs and Circular RNAs in Coronary Artery Disease

“…Forced overexpression of circZNF609 has enhanced production of inflammatory cytokines IL-6 and TNF-α, while enhancing expression of IL-10. These effects are possibly mediated through sponging miRNAs ( 66 ). In an eminent study, Guo et al ( 67 ) have assessed levels of hsa_circ_0002984, hsa_circ_0010283, and hsa_circ_0029589 in human peripheral blood mononuclear cell–originated macrophages from CAD patients and evaluated the consequences of overexpression or silencing of these circRNAs.…”

“…Expression of circZNF609 has been shown to be reduced in peripheral blood leukocytes of CAD patients in correlation with levels of CRP and lymphocyte counts. In addition, down-regulation of circZNF609 has been associated with higher risks of CAD with accuracy of 0.761 ( 66 ). In a high-throughput circRNA profiling, Zhang et al have demonstrated differential expression of 22 circRNAs between CAD patients and healthy subjects.…”

Novel Applications of NSAIDs: Insight and Future Perspectives in Cardiovascular, Neurodegenerative, Diabetes and Cancer Disease Therapy

“…Several theories have been proposed to explain the pathogenesis of atherosclerosis and in the particular inflammatory response, however, the detailed mechanisms of inflammation in atherosclerosis development have not been fully clarified, and effective diagnostic and therapeutic approaches remain limited. Studies demonstrated that the expression of miR-16 was downregulated in the cell and animal models of atherosclerosis, as the main contributor to CAD, thus these findings suggest, that the miR-16 gene from miR-16 microRNA precursor’s family may be a potential diagnostic biomarker and therapeutic target for atherosclerosis anti-inflammatory therapy [ 161 , 162 ].…”

The Contribution of Endothelial-Mesenchymal Transition to Atherosclerosis

“…More recently, in vivo studies demonstrated that injection of miR-16 agomiR into ApoE −/− mice reduces the formation of atherosclerotic plaques and inhibits the proinflammatory cytokines, including IL-6, TNF-α, MCP-1, and IL-1β, in the plasma and tissues, but promotes the secretion of anti-inflammatory factors, including IL-10 and TGF-β. They found that miR-16 might downregulate target program cell death 4 (PDCD4) to activate p38 and ERK1/2 and inactivate the JNK pathway [67]. However, these reports suggest that inhibition of individual inflammatory cytokines is not enough to be effective in treating atherosclerosis.…”