黑芝麻种皮结合态多酚通过线粒体内源性通路诱导HepG2细胞凋亡

BLACK SESAME SEED-COAT BOUND POLYPHENOLS INDUCE APOPTOSIS IN HEPG2 CELLS THROUGH MITOCHONDRIAL ENDOGENOUS PATHWAY

目的研究黑芝麻种皮结合态多酚(BSBP)对HepG2细胞增殖抑制及诱导其凋亡的作用。方法利用MTT法测定BSBP对HepG2细胞的抑制率;利用紫外光谱法与红外光谱法鉴定BSBP的成分;利用流式细胞术检测HepG2细胞的周期阻滞、线粒体膜电位以及凋亡情况;利用比色法测定HepG2细胞的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPX)的活性;利用酶标仪检测HepG2细胞中活性氧(ROS)的荧光强度,caspase3、9的酶活性变化。结果BSBP的主要成分可能为多羟基黄酮。BSBP对HepG2细胞增殖有极显著的抑制作用,并将细胞周期阻滞在G1期,进而诱导HepG2细胞凋亡。BSBP能够降低线粒体膜电位,激活caspase3、9酶活性,说明BSBP可以通过线粒体内源性通路诱导HepG2细胞程序性凋亡。BSBP可以使HepG2细胞的ROS过量产生,同时上调了SOD酶活性,下调了GPX和CAT酶活性,说明BSBP可以诱导ROS过量积累,从而促进细胞凋亡。结论BSBP能够显著抑制HepG2细胞增殖,通过线粒体内源性通路诱导HepG2细胞程序性凋亡.

Objective This study investigated the potential inhibitory effects of a black sesame seed-coat bound polyphenol(BSBP)extract on HepG2 cell proliferation and on apoptosis.Methods Cell viability and proliferation were measured by MTT assays in HepG2 cells after treated with BSBP.The components of BSBP were identified using IR/UV spectroscopy.The cell cycle,mitochondrial membrane potential,and apoptosis were assayed using flow cytometry.The activities of superoxide dismutase(SOD),catalase(CAT),and glutathione peroxidase(GPX)activities were measured using colorimetric assays.The fluorescence intensity of reactive oxygen species(ROS)and caspase 3 and caspase 9 enzyme activities were measured using a fluorescence microplate reader.Results The main components of BSBP were polyhydroxyflavones.BSBP significantly inhibited the proliferation of HepG2 cells,blocked the cell cycle in the G1 phase,and thereby led to apoptosis.BSBP also reduced mitochondrial membrane potential and increased the activities of both caspase 3 and caspase 9,which is associated with the induction of apoptosis in HepG2 cells via the endogenous mitochondrial pathway.Excess ROS generation was observed following BSBP treatment in HepG2 cells,with increased SOD and decreased GPX and CAT activities,indicaties that BSBP promoted apoptosis by inducing excessive accumulation of ROS.Conclusion The major BSBP components are polyhydroxyflavones that induce the apoptosis of HepG2 cells through the endogenous mitochondrial pathway.[ACTA NUTRIMENTA SINICA,2020,42(4):374-381]