CircRNA mmu_circ_0000021 regulates microvascular function via the miR-143-3p/NPY axis and intracellular calcium following ischemia/reperfusion injury

Dysregulation of micro-RNA 143-3p as a Biomarker of Carotid Atherosclerosis and the Associated Immune Reactions During Disease Progression

Atherosclerosis commonly remains undiagnosed until disease manifestations occur. The disease is associated with dysregulated micro(mi)RNAs, but how this is linked to atherosclerosis-related immune reactions is largely unknown. A mouse model of carotid atherosclerosis, human APOB100-transgenic Ldlr-/- (HuBL), was used to study the spatiotemporal dysregulation of a set of miRNAs. Middle-aged HuBL mice with established atherosclerosis had decreased levels of miR-143-3p in their carotid arteries. In young HuBL mice, early atherosclerosis was observed in the carotid bifurcation, which had lower levels of miR-15a-5p, miR-143-3p, and miR-199a-3p, and higher levels of miR-155-5p. The dysregulation of these miRNAs was reflected by specific immune responses during atheroprogression. Finally, levels of miR-143-3p were 70.6% lower in extracellular vesicles isolated from the plasma of patients with carotid stenosis compared to healthy controls. Since miR-143-3p levels progressively decrease when transitioning between early and late experimental carotid atherosclerosis, we propose it as a biomarker for atherosclerosis.

Inhibition of miR-143-3p alleviates myocardial ischemia reperfusion injury via limiting mitochondria-mediated apoptosis

MicroRNA (miR)-143-3p is a potential regulatory molecule in myocardial ischemia/reperfusion injury (MI/RI), wherein its expression and pathological effects remains controversial. Thus, a mouse MI/RI and cell hypoxia/reoxygenation (H/R) models were built for clarifying the miR-143-3p's role in MI/RI. Following myocardial ischemia for 30 min, mice underwent reperfusion for 3, 6, 12 and 24 h. It was found miR-143-3p increased in the ischemic heart tissue over time after reperfusion. Cardiomyocytes transfected with miR-143-3p were more susceptible to apoptosis. Mechanistically, miR-143-3p targeted B cell lymphoma 2 (bcl-2). And miR-143-3p inhibition reduced cardiomyocytes apoptosis upon H/R, whereas it was reversed by a specific bcl-2 inhibitor ABT-737. Of note, miR-143-3p inhibition upregulated bcl-2 with better mitochondrial membrane potential (Δψm), reduced cytoplasmic cytochrome c (cyto-c) and caspase proteins, and minimized infarction area in mice upon I/R. Collectively, inhibition of miR-143-3p might alleviate MI/RI via targeting bcl-2 to limit mitochondria-mediated apoptosis. To our knowledge, this study further clarifies the miR-143-3p's pathological role in the early stages of MI/RI, and inhibiting miR-143-3p could be an effective treatment for ischemic myocardial disease.