Long Non-coding RNA PVT1 Inhibits miR-30c-5p to Upregulate Rock2 to Modulate Cerebral Ischemia/Reperfusion Injury Through MAPK Signaling Pathway Activation

Abstract

Long non-coding RNAs (lncRNAs) play a key role in a variety of disease processes. Plasmacytoma variant translocation 1 (PVT1), a lncRNA, is known to regulate cell functions and play a key role in the pathogenesis of many malignant tumors. The function and molecular mechanisms of lncRNA-PVT1 in cerebral ischemia remain unknown. Real-time PCR (qRT-PCR) was used to detect lncRNA-PVT1 and microRNA-30c-5p (miR-30c-5p) expression in the brain tissues of mice underwent middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reperfusion (OGD/R)-treated mouse primary brain neurons. Gain- or loss-of-function approaches were used to manipulate PVT1, miR-30c-5p, and Rho-associated protein kinase 2 (Rock2). The mechanism of PVT1 in ischemic stroke was evaluated both in vivo and in vitro via bioinformatics analysis, CCK-8, flow cytometry, TUNEL staining, luciferase activity assay, RNA FISH, and Western blot. PVT1 was upregulated in the brain tissues of mice treated with MCAO/R and primary cerebral cortex neurons of mice treated with OGD/R. Mechanistically, PVT1 knockdown resulted in a lower infarct volume and ameliorated neurobehavior in MCAO mice. Consistent with in vivo results, PVT1 upregulation significantly decreased the viability and induced apoptosis of neurons cultured in OGD/R. Moreover, we demonstrated that PVT1 acts as a competitive endogenous RNA (ceRNA) that competes with miR-30c-5p, thereby negatively regulating its endogenous target Rock2. Overexpression of miR-30c-5p significantly promoted cell proliferation and inhibited apoptosis. Meanwhile, PVT1 was confirmed to target miR-30c-5p, thus activating Rock2 expression, which finally led to the activation of MAPK signaling. We demonstrated that PVT1, as a ceRNA of miR-30c-5p, could target and regulate the level of Rock2, which aggravates cerebral I/R injury via activation of the MAPK pathway. These findings reveal a new function of PVT1, which helps to broadly understand cerebral ischemic stroke and provide a new treatment strategy for this disease.