miR-140-5p regulates vascular smooth muscle cell viability, migration and apoptosis by targeting ROBO4 gene expression in atherosclerosis

Circ_0104652 Promotes the Proliferation and Migration of ox-LDL-Stimulated Vascular Smooth Muscle Cells via Stabilizing ADAMTS7 and HMGB1

BACKGROUND

Atherosclerosis (AS) stands as the primary contributor to cardiovascular disease, a pervasive global health concern. Extensive research has underscored the pivotal role of circular RNAs (circRNAs) in cardiovascular disease development. However, the specific functions of numerous circRNAs in AS remain poorly understood.

METHODS

Quantitative real-time PCR analysis revealed a significant upregulation of circ_0104652 in oxidized low-density lipoprotein (ox-LDL)-induced vascular smooth muscle cells (VSMCs). Loss-of-function experiments were subsequently employed to assess the impact of circ_0104652 on ox-LDL-induced VSMCs.

RESULTS

Silencing circ_0104652 was found to impede the proliferation and migration while promoting the apoptosis of ox-LDL-stimulated VSMCs. Mechanistic assays unveiled that circ_0104652 stabilized ADAM metallopeptidase with thrombospondin type 1 motif 7 (ADAMTS7) and high mobility group box 1 (HMGB1) by recruiting eukaryotic translation initiation factor 4A3 (EIF4A3) protein. Rescue assays further confirmed that circ_0104652 exerted its influence on ox-LDL-induced VSMC proliferation through modulation of ADAMTS7 and HMGB1.

CONCLUSIONS

This study elucidates the role of the circ_0104652/EIF4A3/ADAMTS7/HMGB1 axis in ox-LDL-stimulated VSMCs, providing valuable insights into the intricate mechanisms involved.

Myogenic exosome miR-140-5p modulates skeletal muscle regeneration and injury repair by regulating muscle satellite cells

Muscle satellite cells (SCs) play a crucial role in the regeneration and repair of skeletal muscle injuries. Previous studies have shown that myogenic exosomes can enhance satellite cell proliferation, while the expression of miR-140-5p is significantly reduced during the repair process of mouse skeletal muscle injuries induced by BaCl2. This study aims to investigate the potential of myogenic exosomes carrying miR-140-5p inhibitors to activate SCs and influence the regeneration of injured muscles. Myogenic progenitor cell exosomes (MPC-Exo) and contained miR-140-5p mimics/inhibitors myogenic exosomes (MPC-Exo140+ and MPC-Exo140-) were employed to treat SCs and use the model. The results demonstrate that miR-140-5p regulates SC proliferation by targeting Pax7. Upon the addition of MPC-Exo and MPC-Exo140-, Pax7 expression in SCs significantly increased, leading to the transition of the cell cycle from G1 to S phase and an enhancement in cell proliferation. Furthermore, the therapeutic effect of MPC-Exo140- was validated in animal model, where the expression of muscle growth-related genes substantially increased in the gastrocnemius muscle. Our research demonstrates that MPC-Exo140- can effectively activate dormant muscle satellite cells, initiating their proliferation and differentiation processes, ultimately leading to the formation of new skeletal muscle cells and promoting skeletal muscle repair and remodeling.

Exosomes Promote Atherosclerosis Progression by Regulating Circ_100696/miR-503-5p/PAPPA Axis-Mediated Vascular Smooth Muscle Cells Proliferation and Migration

Circular RNAs (circRNAs) are known to play a crucial role in the progression of atherosclerosis (AS). In this study, we aim to explore the function of oxidized low-density lipoprotein (ox-LDL)-induced macrophage-derived exosomal circ_100696 in AS.THP-1 macrophages were induced by ox-LDL to mimic AS cell model. A quantitative real-time polymerase chain reaction (qRT-PCR) assay was applied to determine the expression of circ_100696, microRNA-503-5p (miR-503-5p), and pregnancy-associated plasma protein A (PAPPA). The morphology and size distribution of exosomes were examined by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). Western blot assay was performed for protein levels. Cell proliferation was assessed using 5-ethynyl-2'-deoxyuridine (EdU) assay. Flow cytometry analysis was performed to analyze the cell cycle. Wound-healing assay and transwell assay were done to examine cell migration. RNA pull-down assay, dual-luciferase reporter assay, and RNA immunoprecipitation (RIP) assay were employed to analyze the relationship among circ_100696, miR-503-5p, and PAPPA.Circ_100696 level was increased in ox-LDL-induced THP-1 macrophages and ox-LDL-treated THP-1 macrophage-derived exosomes (OM-Exo). OM-Exo promoted the proliferation, cell cycle, and migration of vascular smooth muscle cells (VSMCs). Circ_100696 was upregulated in VSMCs cocultured with OM-Exo. Circ_100696 knockdown reversed the effects of OM-Exo on VSMC proliferation and migration. Circ_100696 was demonstrated to function as the sponge for miR-503-5p, and miR-503-5p directly targeted PAPPA. Circ_100696 overexpression facilitated VSMC proliferation and migration, with miR-503-5p upregulation or PAPPA silencing reversing these effects. Moreover, circ_100696 overexpression promoted PAPPA expression by targeting miR-503-5p.OM-Exo promoted VSMC growth and migration by regulating the circ_100696/miR-503-5p/PAPPA axis, thereby promoting AS progression.

miR-140-5p and miR-140-3p: Key Actors in Aging-Related Diseases?

microRNAs (miRNAs) are small single strand non-coding RNAs and powerful gene expression regulators. They mainly bind to the 3′UTR sequence of targeted mRNA, leading to their degradation or translation inhibition. miR-140 gene encodes the pre-miR-140 that generates the two mature miRNAs miR-140-5p and miR-140-3p. miR-140-5p/-3p have been associated with the development and progression of cancers, but also non-neoplastic diseases. In aging-related diseases, miR-140-5p and miR-140-3p expressions are modulated. The seric levels of these two miRNAs are used as circulating biomarkers and may represent predictive tools. They are also considered key actors in the pathophysiology of aging-related diseases. miR-140-5p/-3p repress targets regulating cell proliferation, apoptosis, senescence, and inflammation. This work focuses on the roles of miR-140-3p and miR-140-5p in aging-related diseases, details their regulation (i.e., by long non-coding RNA), and reviews the molecular targets of theses miRNAs involved in aging pathophysiology.