Objective:To investigate the effect of circular RNA (circRNA)_005987 on contrast-associated acute kidney injury (CA-AKI) and its mechanism, and provide new ideas for the prevention and treatment of CA-AKI.Methods:CA-AKI rat models and HK-2 cell injury models were established using iopromide, and CA-AKI-related circRNA_005987 was screened based on circRNA expression chip and real-time quantitative PCR (RT-qPCR). Knockdown and overexpression of circRNA_005987 were performed in HK-2 cell model, respectively. Cell counting kit-8 (CCK-8) and Edu staining assays were used to evaluate cell proliferation. Western blotting was used to detect the protein expression of autophagy-related protein microtubule-associated protein 1 light chain 3B (LC3B), P62, beclin-1 and autophagy-related gene 14 (ATG14). Immunofluorescence staining was used to detect protein expression of LC3B. Electron microscope was used to observe the autophagosome formation. Autophagy activator rapamycin and autophagy inhibitor 3-methyladenine were used for in vitro rescue experiments to observe the changes of the above indicators. Mechanistically, bioinformatics analysis was applied to analyze the binding site among circRNA_005987, miR-129-5p and ATG14, and dual luciferase reporter assay was used to verify their interactions. CircRNA_005987 was knocked down and overexpressed in HK-2 cell model, and RT-qPCR was used to detect the expression of miR-129-5p. HK-2 cells were treated with miR-129-5p inhibitor and mimic, Western blotting was used to detect the protein expression of ATG14, and CCK8 and Edu staining assays were used to evaluate cell proliferation. Results:CircRNA_005987 expression was up-regulated in vitro and vivo CA-AKI models (both P<0.05). Overexpression of circRNA_005987 inhibited cell proliferation and promoted cell autophagy, while knockdown of circRNA_005987 had opposite effects (all P<0.05). In vitro rescue experiments confirmed that circRNA_005987 inhibited cell proliferation by activating autophagy ( P<0.05). The dual luciferase reporter assay suggested that there was an interaction between circRNA_005987, miR-129-5p and ATG14. Knockdown of circRNA_005987 increased miR-129-5p expression, while overexpression of circRNA_005987 inhibited miR-129-5p expression (both P<0.05). Knockdown of miR-129-5p inhibited cell proliferation, while overexpression of miR-129-5p reversed the effect (both P<0.05). Conclusion:CircRNA_005987 promotes CA-AKI through activating autophagy via sponging miR-129-5p, suggesting that circRNA_005987 plays an important role in the pathological process of CA-AKI.

Objective:To investigate the effect of circular RNA (circRNA)_005987 on contrast-associated acute kidney injury (CA-AKI) and its mechanism, and provide new ideas for the prevention and treatment of CA-AKI.Methods:CA-AKI rat models and HK-2 cell injury models were established using iopromide, and CA-AKI-related circRNA_005987 was screened based on circRNA expression chip and real-time quantitative PCR (RT-qPCR). Knockdown and overexpression of circRNA_005987 were performed in HK-2 cell model, respectively. Cell counting kit-8 (CCK-8) and Edu staining assays were used to evaluate cell proliferation. Western blotting was used to detect the protein expression of autophagy-related protein microtubule-associated protein 1 light chain 3B (LC3B), P62, beclin-1 and autophagy-related gene 14 (ATG14). Immunofluorescence staining was used to detect protein expression of LC3B. Electron microscope was used to observe the autophagosome formation. Autophagy activator rapamycin and autophagy inhibitor 3-methyladenine were used for in vitro rescue experiments to observe the changes of the above indicators. Mechanistically, bioinformatics analysis was applied to analyze the binding site among circRNA_005987, miR-129-5p and ATG14, and dual luciferase reporter assay was used to verify their interactions. CircRNA_005987 was knocked down and overexpressed in HK-2 cell model, and RT-qPCR was used to detect the expression of miR-129-5p. HK-2 cells were treated with miR-129-5p inhibitor and mimic, Western blotting was used to detect the protein expression of ATG14, and CCK8 and Edu staining assays were used to evaluate cell proliferation. Results:CircRNA_005987 expression was up-regulated in vitro and vivo CA-AKI models (both P<0.05). Overexpression of circRNA_005987 inhibited cell proliferation and promoted cell autophagy, while knockdown of circRNA_005987 had opposite effects (all P<0.05). In vitro rescue experiments confirmed that circRNA_005987 inhibited cell proliferation by activating autophagy ( P<0.05). The dual luciferase reporter assay suggested that there was an interaction between circRNA_005987, miR-129-5p and ATG14. Knockdown of circRNA_005987 increased miR-129-5p expression, while overexpression of circRNA_005987 inhibited miR-129-5p expression (both P<0.05). Knockdown of miR-129-5p inhibited cell proliferation, while overexpression of miR-129-5p reversed the effect (both P<0.05). Conclusion:CircRNA_005987 promotes CA-AKI through activating autophagy via sponging miR-129-5p, suggesting that circRNA_005987 plays an important role in the pathological process of CA-AKI.