Folate deficiency induces a cell cycle-specific apoptosis in HepG2 cells

被引:87
作者
Huang, RFS
Ho, YH
Lin, HL
Wei, JS
Liu, TZ [1 ]
机构
[1] Yuans Gen Hosp, Dept Med Res, Kaohsiung, Taiwan
[2] Chang Gung Univ, Sch Med Technol, Grad Inst Basic Med, Tao Yuan, Taiwan
[3] Fu Jen Univ, Dept Nutr & Food Sci, Hsin Chuang, Taiwan
关键词
folate deficiency; HepG2; cells; apoptosis; cell cycle arrest; DNA fragmentation;
D O I
10.1093/jn/129.1.25
中图分类号
R15 [营养卫生、食品卫生]; TS201 [基础科学];
学科分类号
100403 ;
摘要
The human hepatoma HepG2 cell line was chosen as a representative of solid tissue-derived cell systems in which folate metabolism and apoptosis induction have not been thoroughly investigated. HepG2 cells were cultivated in the control or folate-deficient media (control media lacking of folate, glycine, thymidine and hypoxanthine) for 4 wk. This resulted in a decrease in intracellular folate levels to 32% of the control within 1 wk, which was followed by growth arrest and greater cell death rates. These disturbances of folate deficiency coincided with apoptotic induction, as characteristically shown by nucleosomal DNA fragmentation of 180-200 base pair multimers, nuclear chromatin condensation and positive terminal transferase-mediated dUTP nick end labeling assay. Apoptosis coincided with an accumulation of cells in S-phase, a subsequent G2/M phase block and a significant increase in mean protein content as evaluated by flow cytometric analyses employing a double-staining method. The growth and cell cycle arrest under folate-deficient conditions was independent of a change of p53 expression as measured by an enzyme-linked immunosorbent assay. Supplementation of 2 mu mol/L folate normalized cell cycles and diminished DNA fragmentation. Taken together, these data indicate that HepG2 cells cultivated in folate-deficient medium have a low folate concentration, decreased growth and viability, and increased apoptotic propensity. This occurrence of apoptosis was associated with a cell cycle-specific mechanism and independent of p53-mediated pathway.
引用
收藏
页码:25 / 31
页数:7
相关论文
共 41 条
[1]   P53 CONTROLS BOTH THE G(2)/M AND THE G(1) CELL-CYCLE CHECKPOINTS AND MEDIATES REVERSIBLE GROWTH ARREST IN HUMAN FIBROBLASTS [J].
AGARWAL, ML ;
AGARWAL, A ;
TAYLOR, WR ;
STARK, GR .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1995, 92 (18) :8493-8497
[2]  
BELLAMY CO, 1997, BR MED B, V53, P5228
[3]   NUTRITIONAL FOLATE-DEFICIENCY IN CHINESE-HAMSTER OVARY CELLS .1. CHARACTERIZATION OF THE PLEIOTROPIC RESPONSE AND ITS MODULATION BY NUCLEIC-ACID PRECURSORS [J].
BORMAN, LS ;
BRANDA, RF .
JOURNAL OF CELLULAR PHYSIOLOGY, 1989, 140 (02) :335-343
[4]  
BRADFORD MM, 1976, ANAL BIOCHEM, V72, P248, DOI 10.1016/0003-2697(76)90527-3
[5]  
BRANDA RF, 1993, CANCER RES, V53, P5401
[6]   METHYL DEFICIENCY, DNA METHYLATION, AND CANCER - STUDIES ON THE REVERSIBILITY OF THE EFFECTS OF A LIPOTROPE-DEFICIENT DIET [J].
CHRISTMAN, JK ;
CHEN, ML ;
SHEIKHNEJAD, G ;
DIZIK, M ;
ABILEAH, S ;
WAINFAN, E .
JOURNAL OF NUTRITIONAL BIOCHEMISTRY, 1993, 4 (12) :672-680
[7]   TISSUE DISTRIBUTION AND PREDICTION OF TOTAL-BODY FOLATE OF RATS [J].
CLIFFORD, AJ ;
HEID, MK ;
MULLER, HG ;
BILLS, ND .
JOURNAL OF NUTRITION, 1990, 120 (12) :1633-1639
[8]   A BIOCHEMICAL HALLMARK OF APOPTOSIS - INTERNUCLEOSOMAL DEGRADATION OF THE GENOME [J].
COMPTON, MM .
CANCER AND METASTASIS REVIEWS, 1992, 11 (02) :105-119
[9]  
DAVIDOFF AN, 1993, EXP HEMATOL, V21, P922
[10]  
DELBINO G, 1991, CANCER RES, V51, P1165