Circular RNA circ_0003609 ameliorates hypertrophied ligamentum flavum by regulating the miR-155/SIRT1 axis

Background:Hypertrophy of the ligamentumflavum(HLF)is a common contributor to spinal stenosis which results in significant neurological impairments.Circular RNA(circRNA)circ_0003609 has been linked to HLF;however,the exact mechanism by which it causes this disease is unclear.Methods:Circ_0003609 expressions were regulated in HLF cells by overexpression vectors and RNA interference.Cell proliferation andfibrosis-related gene expression were checked by the Cell Counting Kit-8(CCK-8)assay and western blotting.CircBank’s prediction of the association between miR-155 and circ_0003609 was supported by a dual-luciferase reporter experiment.The function of the miR-155/sirtuin 1(SIRT1)axis in controlling HLFfibrosis was further examined.Results:Overexpression of circ_0003609 suppressed HLF cell propagation andfibrosis compared to its silencing.It was found that circ_0003609 served as the sponge for miR-155 and that the circ_0003609/miR-155 axis controlled thefibrosis of HLF cells.It was found that circ_0003609 acted as a sponge for miR-155,regulating thefibrosis of HLF cells.Further,miR-155 targets SIRT1,and the miR-155/SIRT1 axis promotes HLF cellfibrosis.Conclusion:Circ_0003609 ameliorates hypertrophied ligamentumflavum(LF)by modulating the miR-155/SIRT1 axis,indicating a potential treatment approach for HLF.