Circular RNA Expression Profile And Preliminary Study On Function And Mechanism Of CircSNHG5 In Cartilage Endplate

Background:Intervertebral disc degeneration is the main cause of neck pain and low back pain,but its pathogenesis is still unclear.Endplate cartilage dysfunction is an initiating factor for intervertebral disc degeneration.Recent studies have shown that circRNA play an important role in the development of intervertebral disc degeneration,however,its functional mechanism in endplate chondrocytes has not been elucidated.In this study,we aimed to analyze the expression profile of circRNA in endplate cartilage,and to explore its functional mechanism in the process of endplate degeneration.Methods:The expression profile of circular RNA in degenerated and normal human endplate cartilage was analyzed by using microarray and bioinformatics technology.Differentially expressed circRNA were verified using q RT-PCR,and circ SNHG5 was identified by Sanger sequencing and RNA fluorescence in situ hybridization.Western blot,immunofluorescence were used to detect the function of circ SNHG5 in chondrocytes,and dual luciferase experiments were used to verify the targeting relationship between circ SNHG5 and mi R-495-3p and mi R-495-3p and CITED2.Results:A total of 578 circRNA were detected differentially expressed in degenerated and normal human endplate cartilage,of which 231 were up-regulated and 64 were down-regulated.The q RT-PCR results showed that the expression level of circ SNHG5 was significantly down-regulated in degenerated endplate cartilage.Meanwhile,knockdown of the circ SNHG5 gene in human chondrocytes resulted in decreased cell proliferation and extracellular matrix degradation.In addition,dual-luciferase experiments confirmed that circ SNHG5 could bind to mi R-495-3p and regulate the expression of the downstream gene CITED2.Through overexpression and knockout of CITED2,we further verified this mechanism of action.Conclusion:Circ SNHG5 promotes chondrocyte proliferation and inhibits ECM degradation by mediating mi R-495-3p/CITED2 signaling pathway,while silencing circ SNHG5 can inhibit the degeneration of endplate cartilage.Therefore,circ SNHG5 may be a potential therapeutic target for the treatment of IDD.