ABSTRACT
Objective To investigate the effects of saturated fatty acids and unsaturated fatty acids on proliferation and autophagy of human lung cancer cells. Methods The lung cancer cells A549 were treated with stearic acid (saturated fatty acid) and doconexent (DHA, unsaturated fatty acid), respectively, in concentrations of 0, 30, 60, 120 and 240μmol/L. MTT test and cell clone formation assay were performed to detect the proliferation of A549 cells. The morphology of A549 autophagy was observed by confocal laser scanning microscopy after A549 cells were treated with stearic acid or DHA for 24 hours. Western blotting assay was used to detect the expression of autophagy-related protein after A549 cells were treated with stearic acid or DHA for 12, 24 and 36 hours, respectively. Results 30-240μmol/L stearic acid or DHA both inhibited the proliferation of A549 cells (P<0.05). Both stearic acid and DHA induced autophagy of A549 cells, meanwhile, down-regulated Phospho-mTOR (ser2481) and up-regulated LC3Ⅱ/LC3Ⅰ of A549 cells (P<0.05). Conclusions Both saturated fatty acid and unsaturated fatty acid can inhibit the proliferation and induce autophagy of lung cancer cells. The mechanisms of autophagy may be related to Phospho-mTOR (ser2481) signaling pathway.
ABSTRACT
Objective Galangin is a natural flavonoid with antineoplastic activity .SIRT1 is an important member of Sirtuin family which parcitipate in many physiological process .The aim of this study was to investigate the effect of SIRT 1 on HepG2 cell apop-tosis induced by galangin . Methods HepG2 cells were pre-treated with SIRT1 inhibitor EX-527 for 2 hours, and then galangin for 24 hours.DMSO solvent control group, EX-527 treatment group, galangin treatment group and EX-527 and galangin co-treatment group were established.Hoechst 33342 staining, flow cytometry and western blot were performed to detect the apoptosis of HepG2 cells.After regu-lating the expression of SIRT1 in HepG2 cells with RNA interference and transfection of exogenous genes , these cells were treated with ga-langin for 24 hours.Negative control group , vector control group , SIRT1 knock down group , blank control group , blank vector group ,and SIRT1 upregulation group were established .Western blot and Flow cytometry were performed to detect the apoptosis of HepG 2 cells. Results The apoptosis rate and the gray level ratio of shear band of PARP 1 and GAPDH that of galangin group [(11.62± 0.55) %, 0.89±0.01]and EX-527+galangin group[(25.75±0.61) %, 1.15±0.06] were all increased(P<0.01),when these were compared with DMSO solvent control group [(2.49±0.22) %, 0.06±0.00];and those in EX-527+galangin group were also markedly increased compared with galangin group (P<0.01).The result of western bolt was that the gray level ratio of PARP 1 and GAPDH of SIRT1 knocked down group(0.06±0.01) was markedly decreased compared with vector control group (1.11±0.05)and without adenovi-rus infection group (1.10±0.04)(P<0.01).The apoptosis rate and the gray level ratio of shear band of PARP 1 and GAPDH that of SIRT1 knocked down group were markedly increased compared with vector control group and without adenovirus infection group ( P<0.01).The gray level ratio of PARP1 and GAPDH of SIRT1 up-regulated group (1.63±0.04) was markedly increased compared with blank control group (0.89±0.02) and without plasmid transfection group (0.87±0.03) (P<0.01).The apoptosis rate and the gray lev-el ratio of shear band of PARP 1 and GAPDH that of SIRT1 up-regulated group were markedly decreased compared with blank control group and without plasmid transfection group (P<0.01). Conclusion SIRT1 inhibited galangin-induced apoptosis in HepG2 cells.
ABSTRACT
Objective Galangin has various antitumor activities and digital holographic microscopy ( DHM ) .This study aimed to investigate the detection of galangin-induced apoptosis of HepG2 cells using DHM. Methods HepG2 cells were cultured in vitro and treated with galangin at 130 μmol/L for 6, 12, and 24 hours respectively to induce apoptosis.Then, MTT assay was used to detect the proliferation of the HepG2 cells, Hoechst 33342 staining and flow cytometry adopted to determine their apoptosis, and DHM employed to visualize their morphological changes. Results Compared with the blank controls, galangin significantly inhibited the proliferation of the HepG2 cells ([7.32 ±2.47]%vs [39.14 ±2.04]%, P<0.01) and obviously induced their nuclear condensa-tion and apoptosis, with a total apoptosis rate of (11.550 ±0.043)%at 24 hours.DHM showed statistically significant differences be-tween the galangin-treated and control groups in the morphological changes of the HepG2 cells at the three time points (P<0.05). Conclusion Digital holographic microscopy can be used to detect the morphological changes of HepG2 cells during galangin-induced apop-tosis.