The Effect Of Rosiglitazone On Expression Of MAP1-LC3in HepG2Cells

Objective:To Investigate the relationship between the stimulation of rosiglitazone and the expression of MAP1-LC3as well as the level of autophagy in HepG2cells, by detecting the effects of different concentrations of rosiglitazone on the expression of MAP1-LC3in HepG2cells.Methods:The cultured HepG2cells were stimulated by different concentrations of rosiglitazone (10、30、50μmol/L, a different concentration grade was set individually for the CCK-8assays) for24hours in vitro. We used the CCK-8assays to detect the inhibition rate of the proliferation of the HepG2cells; the immunohistochemistry staining was applied to show the expression of LC3in the HepG2cells before and after the rosiglitazone stimulus; the changes of cellular ultrastructure before and after the drug acts were observed by an electron microscope; MDC staining was employed to detect the appearance of the autophagosomes in HepG2cells; the apoptosis of HepG2cells under different concentrations of rosiglitazone was assayed by flow cytometry.Results:①The CCK-8assays showed, the proliferation of HepG2cells stimulated by different concentrations of rosiglitazone (10、20、40、80、160、320μmol/L) for24hours was restrained, with the increase of drug concentration, the proliferation inhibition of HepG2cells became more evident.②The immunohistochemistry staining indicated that the weak expression of LC3was observed in the HepG2cells under the condition of no drug stimulus, and the positive signal of the expression of LC3was mainly distributed in the cytoplasm of HepG2cells. The result also showed, the higher would the concentration of rosiglitazone be, the more expression of LC3would be detected in HepG2cells.③Compared with the control group without the drug stimulus, the existence of intracellular autophagosomes and autophagolysosomes could be observed in HepG2cells treated by rosiglitazone under the electron microscope.④Treated by different concentrations of rosiglitazone for24hours, the MDC staining indicated that the amount of autophagosomes in HepG2cells was greatly increased in the rosiglitazone group with respect to the control group, and the green fluorescent was enhanced in pace with the increased concentration of the rosiglitazone.⑤The result of flow cytometry showed that the percentage of apoptotic cells increased with the increased concentration of rosiglitazone, contrasted to the control group.Conclusion:①Rosiglitazone had an effect on inhibition of the proliferation of the HepG2cells, and Rosiglitazone could induce autophagy in HepG2cells, with dose-effect relationship.②The expression of LC3in HepG2cells in no drug group was weak, which could be related to the rapid growth of hepatoma cells.③After rosiglitazone stimulation, the expression of LC3in HepG2cells was greatly enhanced. The result suggested that the effect of rosiglitazone on growth inhibition in HepG2cells could be associated with the up-regulation of MAP1-LC3and enhanced autophagy.