Effect of vitamin E succinate on autophagy in human gastric cancer cells via mitochondria-associated endoplasmic reticulum membranes
10.3969/j.issn.1000-4718.2025.11.010
- VernacularTitle:基于线粒体相关内质网膜研究维生素E琥珀酸酯对人胃癌细胞自噬的影响
- Author:
Miaomiao CAO
1
;
Fangyu CHEN
;
Zhiyang WEI
;
Mengmeng LÜ
;
Ziqing XING
;
Jinze WANG
;
Shuang LI
;
Liying HOU
Author Information
1. 华北理工大学公共卫生学院,河北 唐山 063210
- Publication Type:Journal Article
- Keywords:
vitamin E succinate;
gastric cancer;
autophagy;
mitochondria-associated endoplasmic reticulum membranes
- From:
Chinese Journal of Pathophysiology
2025;41(11):2157-2165
- CountryChina
- Language:Chinese
-
Abstract:
AIM:This study aims to investigate whether vitamin E succinate(VES)induces autophagy in hu-man gastric cancer cells through the promotion of mitochondria-associated endoplasmic reticulum membranes(MAMs).METHODS:Human gastric cancer cell lines MKN28 and MKN45 were cultured in vitro.Cell viability was assessed us-ing the CCK8 assay,and two cell growth curves were plotted to determine the treatment concentration of VES.Control groups,VES dose groups(MKN28:5,10,20,and 40 mg/L;MKN45:10,20,40,and 80 mg/L),an autophagy-posi-tive control group(rapamycin,RAPA,100 nmol/L),and a MAMs-positive control group(oligomycin A,10 mg/L)were set up.Cells were harvested after 24 h of treatment for subsequent experiments.The formation of autophagosomes and MAMs was observed using transmission electron microscopy.The expression levels of autophagy-related proteins,includ-ing beclin-1,LC3-II/LC3-I,and p62,were detected by Western blot.MAMs labeled with split green fluorescent protein(GFP)were visualized by fluorescence microscopy.The expression of mitofusin 2(MFN2),a key molecule of MAMs,was also detected by Western blot.To inhibit MFN2 specifically,the cells were treated with mitochondrial fusion inhibitor 8(MFI8)and simultaneously transfected with an MFN2 plasmid to achieve MFN2 overexpression(OE-MFN2).The cells were divided into control group,MFI8(20 μmol/L)group,VES groups(20 mg/L for MKN28 cells and 40 mg/L for MKN45 cells),VES+MFI8 group,OE-MFN2+MFI8 group and OE-MFN2+VES+MFI8 group.The MAMs were visualized by fluorescence microscopy,and the expression changes of MFN2,beclin-1 and LC3-II/I were detected by Western blot.RESULTS:The results of the CCK8 assay showed that VES significantly inhibited the viability of both human gastric can-cer cell lines(P<0.05).After VES treatment,the formation of typical autophagosomes and MAMs was observed in both cell lines by transmission electron microscopy.Fluorescence microscopy showed a significant increase in GFP signals of MAMs.Western blot analysis showed that with increasing doses of VES,the expression levels of MFN2,beclin-1,and LC3-II/I were significantly up-regulated,while that of p62 was significantly down-regulated(P<0.05).Compared with VES group,the cells pretreated with MFI8 followed by VES exposure showed markedly reduced GFP signals of MAMs and much lower protein levels of MFN2,beclin-1 and LC3-II/LC3-I(P<0.05).Transfection with an MFN2 overexpression plasmid rescued MFN2 expression.Compared with VES+MFI8 group,the cells in OE-MFN2+VES+MFI8 group had much higher protein expression levels of MFN2,beclin-1 and LC3-II/LC3-I(P<0.05).CONCLUSION:The VES may partici-pates in the regulation of autophagy in human gastric cancer cells by promoting the formation of MAMs.