Mechanical overload is a critical contributor to cartilage degeneration in osteoarthritis(OA)pathogenesis.Circular RNA(circRNA)is expected to provide a long-lasting therapy for OA.However,the involvement of the circRN...Mechanical overload is a critical contributor to cartilage degeneration in osteoarthritis(OA)pathogenesis.Circular RNA(circRNA)is expected to provide a long-lasting therapy for OA.However,the involvement of the circRNA-associated competitive endogenous RNA network in chondrocyte senescence induced by mechanical overloading remains unestablished.A mechanical overloading-induced chondrocyte senescence model in human primary chondrocytes is constructed,and differences in the expression of circRNAs and miRNAs were analyzed.The biological roles of circKIAA0586/miR-335-5p in chondrocyte senescence and OA progression under mechanical overloading and its downstream targets were determined using gain-and loss-of-function experiments in various biochemical assays in human chondrocytes.The in vivo effects of circKIAA0586 overexpression were also determined in destabilization of the medial meniscus(DMM)OA mice and aged spontaneous OA mice.The mechanical overloading-induced chondrocyte senescence was aggravated by miR-335-5p or circKIAA0586 knockdown.Accumulated DNA damage response was observed following mechanical overloading,which reduced after miR-335-5p inhibition or circKIAA0586 supplementation.MiR-335-5p was regulated by circKIA0586 adsorption.HELLS was prominently down-regulated following mechanical overloading treatment.Moreover,miR-335-5p bound to lymphoid-specific helicase(HELLS)mRNA during mechanical overloading was demonstrated to mediate the nonhomologous end joining(NHEJ)pathway,thereby inducing DNA damage and senescence.In addition,the senescence delaying and cartilage protective functions of circKIAA0586 and HELLS were validated in DMM OA mice and aged spontaneous OA mice.Our findings suggest that miR-335-5p,which escapes circKIAA0586 adsorption,facilitates mechanical overloading-induced chondrocyte senescence and OA progression by impairing the NHEJ pathway through HELLS inhibition.Overall,targeting circKIAA0586/miR-335-5p/HELLS signaling provides a novel therapeutic approach for OA.展开更多
基金supported by grants from the National Natural Science Foundation of China(grant numbers 82322044,82172491,and 32171133)the National Key Research and Development Plan(grant numbers 2022YFC3601900 and 2022YFC3601902)+2 种基金China Postdoctoral Science Foundation(grant number 2022M721517)the Natural Science Foundation of Guangdong Province(grant number 2020A1515011062)the President Foundation of The Third Affiliated Hospital of Southern Medical University(grant numbers YQ202206 and YQ202210).
文摘Mechanical overload is a critical contributor to cartilage degeneration in osteoarthritis(OA)pathogenesis.Circular RNA(circRNA)is expected to provide a long-lasting therapy for OA.However,the involvement of the circRNA-associated competitive endogenous RNA network in chondrocyte senescence induced by mechanical overloading remains unestablished.A mechanical overloading-induced chondrocyte senescence model in human primary chondrocytes is constructed,and differences in the expression of circRNAs and miRNAs were analyzed.The biological roles of circKIAA0586/miR-335-5p in chondrocyte senescence and OA progression under mechanical overloading and its downstream targets were determined using gain-and loss-of-function experiments in various biochemical assays in human chondrocytes.The in vivo effects of circKIAA0586 overexpression were also determined in destabilization of the medial meniscus(DMM)OA mice and aged spontaneous OA mice.The mechanical overloading-induced chondrocyte senescence was aggravated by miR-335-5p or circKIAA0586 knockdown.Accumulated DNA damage response was observed following mechanical overloading,which reduced after miR-335-5p inhibition or circKIAA0586 supplementation.MiR-335-5p was regulated by circKIA0586 adsorption.HELLS was prominently down-regulated following mechanical overloading treatment.Moreover,miR-335-5p bound to lymphoid-specific helicase(HELLS)mRNA during mechanical overloading was demonstrated to mediate the nonhomologous end joining(NHEJ)pathway,thereby inducing DNA damage and senescence.In addition,the senescence delaying and cartilage protective functions of circKIAA0586 and HELLS were validated in DMM OA mice and aged spontaneous OA mice.Our findings suggest that miR-335-5p,which escapes circKIAA0586 adsorption,facilitates mechanical overloading-induced chondrocyte senescence and OA progression by impairing the NHEJ pathway through HELLS inhibition.Overall,targeting circKIAA0586/miR-335-5p/HELLS signaling provides a novel therapeutic approach for OA.
