The Role Of Autophagy-mediated Metabolic Reprogramming Induced By HMGA2 In Cd-induced Migration

Objective:Cadmium?Cd?,which is widely found in industrial and environmental pollutants,is a recognized human carcinogen.Due to its low excretion rate and long half-life,Cd gradually accumulated in tissues of the human body,which caused a variety of organ damage.Occupational Cd exposure is associated with the occurrence of lung cancer.HMGA2 participates in various biological processes and has become a biomarker for tumors.Our previous studies found that HMGA2 plays an important role in Cd-induced cell proliferation and migration.The purpose of this study was to explore possible mechanisms of glucose metabolism reprogramming in Cd-induced migration.Methods:In this study,A549 cells and HELF cells were used as in vitro cell models and BALB/c mice were used as in vivo animal experimental models.After mice were treated with cadmium and transfected with HMGA2 plasmid,the expression of respiratory chain proteins and glycolysis-related proteins in lung tissues was observed by Western blot.After cells were transfected with HMGA2 plasmid and small interfering RNA,the content of glucose and lactic acid in the medium was determined by glucose assay kit and lactic acid assay kit.The effect of HMGA2 on the autophagy,aerobic glycolysis and oxidative respiratory chain proteins expression of A549 and HELF cells was detected by Western blot.Cell scratch test and Western blot was treated to detect cell migration ability and the effect of glycolysis inhibitor 2-deoxy-D glucose?2DG?on cell migration ability and protein.At the same time,the effect of 2DG on oxidative respiratory chain enzyme was observed by Western blot.The effect of 3-Methyladenine?3MA?,an autophagy inhibitor,on glycolysis and oxidative phosphorylation was examined by Western blot.CCCP treatment was used and Western blot was used to observe the effects of CCCP on Cd-induced glycolysis and autophagy.The effect of 2DG on mitochondrial membrane potential used JC-1 staining to observe.Using Mito-Tracker Green to observe the effects of HMGA2 and 2DG on Mitochondrial mass.Results:After Cd Cl₂ treatment,the lung tissues of BALB/c mice were used for Western blot,the expressions of glycolysis-related proteins?GLUT1,HKII,LDHA and PKM2?were all significantly increased and the protein of COXIV and ND1 was significantly decreased in Cd-treated mice compared with the control mice?P<0.05?.After transfection of plasmid HMGA2 in vivo,the expression of glycolysis-related proteins in lung tissues increased,and the expression of COXIV and ND1 decreased?P<0.05?.Consistent with in vivo results,transfection of plasmid HMGA2 in A549 and HELF cells increased glycolysis levels,reduced oxidative phosphorylation levels,and increased glucose absorption and lactic acid production?P<0.05?.Down-regulation of HMGA2 by si HMGA2 reduced glycolysis levels,glucose absorption,and lactic acid production,restores mitochondrial mass,and oxidative phosphorylation?P<0.05?.After treatment with the glycolysis inhibitor 2DG,the invasive ability induced by Cd was significantly reduced?P<0.05?,and the mitochondrial membrane potential and oxidative respiratory enzymes were restored?P<0.05?.CCCP treatment reduced Cd-induced autophagy and glycolysis level?P<0.05?.After up-regulating HMGA2,then treatment with 3MA,the expression of glycolysis-related proteins,MMP-2,and MMP-9 proteins was all reduced compared to the plasmid group?P<0.05?,and Cd-inhibited oxidative respiratory chain enzymes were restored?P<0.05?,suggesting that HMGA2-induced autophagy plays an important role in metabolic reprogramming.Conclusion:Autophagy-mediated metabolic reprogramming induced by HMGA2plays an important role in Cd-induced migration.