Hsa_circ_0000345 regulates the cellular development of ASMCs in response to oxygenized low-density lipoprotein.

The interaction between circRNAs and atherosclerosis has been extensively studied. However, more novel circRNAs need to be explored to help establish a perfect regulatory network. In the present research, hsa_circ_0000345 was demonstrated to regulate cellular development of oxygenized low-density lipoprotein (ox-LDL)-treated aortic smooth muscle cells (ASMCs), which was closely related to the occurrence and progress of atherosclerosis. Ox-LDL exposure remarkably decreased hsa_circ_0000345 expression in ASMCs. Transfection-induced hsa_circ_0000345 overexpression activated cell viability (detected by an MTT assay) and restrained cellular apoptosis (analysed by flow cytometry) in the atherosclerosis cellular model. While down-regulation of hsa_circ_0000345 reduced cell viability and promoted cell apoptosis. In addition, the data of the cell cycle distribution analysis and trans-well assay indicated that cell cycle progression was arrested at the G1 phase while cell invasion was enhanced in ASMCs following treatment of ox-LDL in the context of hsa_circ_0000345 OE plasmids. In addition, up-regulation of hsa_circ_0000345 supported HIF-1α at both the mRNA and protein level, and down-regulation of hsa_circ_0000345 reduced HIF-1α expression. Overall, the above findings revealed that hsa_circ_0000345 was a dramatic regulator of ASMCs proliferation, apoptosis and invasion in response to ox-LDL treatment. Hsa_circ_0000345 was identified as a protector of cell viability during ox-LDL induced cell development.