?-Tocotrienol Inhibits Proliferation Of Human Gastric Cancercells Through Regulating Energy Metabolism

Objective:To investigate the role and mechanism of ?-tocotrienol(?-T3)in energy metabolism,cell proliferation and apoptosis of human gastric adenocarcinoma SGC-7901 and MGC-803 cells.Methods:1.SGC-7901 and MGC-803 cells were treated with different concentrations(0,15,30,45,60 and 80 ?mol/L)of ?-T3 and ?-TOC,for 24 h and 48 h,and the cell proliferation ability was detected by CCK8 method.2.SGC-7901 and MGC-803 cells were treated with 30 ?mol/L ?-T3 for 0,12 and 24 h,and apoptosis was detected by FCM.3.After SGC-7901 and MGC-803 cells were treated with 30 ?mol/L ?-T3 for 0,12 and 24 h,the mitochondrial membrane potential was detected by JC-1 fluorescent probe method.After treated SGC-7901 and MGC-803 cells with 0,20,30?mol/L ?-T3 for 0,4h.The mitochondrial pressure test kit was used to detect the oxygen consumption rate(OCR)level.SGC-7901 and MGC-803 cells were treated with 30?mol/L ?-T3 for 0,12 and 24 h,the levels of reactive oxygen species(ROS)in the cells were detected by DCFH-DA fluorescent probe.The protective effect of the reactive oxygen species remover N-acetylcysteine(NAC)on ?-T3 treated cells was examined and CCK8 method was used.4.After SGC-7901 and MGC-803 cells were treated with 30 ?mol/L ?-T3 for 0,4 and 24 h,protein levels of UQCRC2(subunit of complex III),COX4I1(subunit of complex IV),and ATP5F1A(subunit of complex V)NDUFB8(subunit of complex I)and SDHB(subunit of complex II)were detected by western blot.5.After treated SGC-7901 and MGC-803 cells for 0,4h with 0,20,30?mol/L ?-T3,the effect of extracellular acidification rate(ECAR)was detected by glycolytic rate detection kit.6.Treated SGC-7901 and MGC-803 cells with 30 ?mol/L?-T3 for 0?4h,the ATP rate and total ATP levels in the cells were detected.Results:1.The results of CCK-8 showed that the proliferation inhibition rate of both SGC-7901 and MGC-803 cellshad an increase tendency with the increase of ?-T3 concentration;with the increase of the concentration of ?-TOC,the proliferation inhibition rates of SGC-7901 and MGC-803 cells did not change significantly.(p < 0.05,p < 0.01,p < 0.001).2.FCM showed that the apoptosis rate of both SGC-7901 and MGC-803 cells had increased with the prolongation of T3 action time(p < 0.01,p < 0.001).3.The results showed that the mitochondrial membrane potential(? ? m)levels of SGC-7901 and MGC-803 cells decreased with the prolongation of T3 action time.(p < 0.05,p < 0.01).The OCR results showed that the OCR levels of human gastric adenocarcinoma SGC-7901 and MGC-803 cells were decreased with increasing concentration of ?-T3.(p < 0.05,p < 0.01).The results of ROS test showed that the reactive oxygen species(ROS)in human gastric adenocarcinoma SGC-7901 and MGC-803 cells increased with the prolongation of T3 action time.At the same time,CCK8 results showed that NAC can significantly reduce the inhibition rate of ?-T3 on cells.(p < 0.05,p < 0.01).4.WB results showed that ?-T3 could significantly reduce the protein levels of NDUFB8 and SDHB,but had no effect on UQCRC2,COX4I1,and ATP5F1A(p < 0.05,p < 0.01).The results of ECAR showed that the glycolytic rate of both SGC-7901 and MGC-803 cells had increased compensatory with the increase of ?-T3 concentration.(p < 0.01,p < 0.001).The results of ATP assay showed that the ATP rate and ATP levels of SGC-7901 and MGC-803 cells had decreased with the increase of ?-T3 concentration.(p < 0.05).Conclusion:?-T3 has the effect of inhibiting cell proliferation and inducing apoptosis,and its mechanism may be related to inhibiting protein levels of NDUFB8 and SDHB,increasing ROS production and decreasing ATP level in human gastric SGC-7901 and MGC-803 cells.