title: Effect of diindolylmethane on Ca(2+) movement and viability in HA59T human hepatoma cells.
abstract: The effect of diindolylmethane, a natural compound derived from indole-3-carbinol in cruciferous vegetables, on cytosolic Ca(2+) concentrations ([Ca(2+)](i)) and viability in HA59T human hepatoma cells is unclear. This study explored whether diindolylmethane changed [Ca(2+)](i) in HA59T cells. The Ca(2+)-sensitive fluorescent dye fura-2 was applied to measure [Ca(2+)](i). Diindolylmethane at concentrations of 1-50 μM evoked a [Ca(2+)](i) rise in a concentration-dependent manner. The signal was reduced by removing Ca(2+). Diindolylmethane-induced Ca(2+) influx was not inhibited by nifedipine, econazole, SK&F96365, and protein kinase C modulators but was inhibited by aristolochic acid. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitors thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) inhibited or abolished diindolylmethane-induced [Ca(2+)](i) rise. Incubation with diindolylmethane inhibited thapsigargin or BHQ-induced [Ca(2+)](i) rise. Inhibition of phospholipase C with U73122 reduced diindolylmethane-induced [Ca(2+)](i) rise. At concentrations of 10-75 μM, diindolylmethane killed cells in a concentration-dependent manner. The cytotoxic effect of diindolylmethane was not reversed by chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid. Propidium iodide staining data suggest that diindolylmethane (25-50 μM) induced apoptosis in a concentration-dependent manner. Collectively, in HA59T cells, diindolylmethane induced a [Ca(2+)](i) rise by causing phospholipase C-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) influx via phospholipase A(2)-sensitive channels. Diindolylmethane induced cell death that may involve apoptosis.
authors.affiliation: Department of Medicine, Yongkang Veterans Hospital, Tainan 710, Taiwan.
authors.forename: Jin-Shiung
authors.initials: JS
authors.lastname: Cheng
authors.forename: Su-Shung
authors.initials: SS
authors.lastname: Shu
authors.forename: Chun-Chi
authors.initials: CC
authors.lastname: Kuo
authors.forename: Chiang-Ting
authors.initials: CT
authors.lastname: Chou
authors.forename: Wei-Lun
authors.initials: WL
authors.lastname: Tsai
authors.forename: Yi-Chien
authors.initials: YC
authors.lastname: Fang
authors.forename: Li-Ni
authors.initials: LN
authors.lastname: Kuo
authors.forename: Jeng-Hsien
authors.initials: JH
authors.lastname: Yeh
authors.forename: Wei-Chuan
authors.initials: WC
authors.lastname: Chen
authors.forename: Jau-Min
authors.initials: JM
authors.lastname: Chien
authors.forename: Ti
authors.initials: T
authors.lastname: Lu
authors.forename: Chih-Chuan
authors.initials: CC
authors.lastname: Pan
authors.forename: He-Hsiung
authors.initials: HH
authors.lastname: Cheng
authors.forename: Kuo-Liang
authors.initials: KL
authors.lastname: Chai
authors.forename: Chung-Ren
authors.initials: CR
authors.lastname: Jan
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival; D004305:Dose-Response Relationship, Drug; D004464:Econazole / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D016257:Fura-2 / Q000378:metabolism; D006801:Humans; D006873:Hydroquinones / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D007211:Indoles / Q000494:pharmacology*; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D009543:Nifedipine / Q000494:pharmacology; D054467:Phospholipases A2 / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D013778:Tetrazolium Salts / Q000032:analysis / Q000378:metabolism; D019284:Thapsigargin / Q000494:pharmacology
chemical_list: C110656:2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium; D002121:Calcium Channel Blockers; D006873:Hydroquinones; D007093:Imidazoles; D007211:Indoles; D013778:Tetrazolium Salts; C019359:2,5-di-tert-butylhydroquinone; D019284:Thapsigargin; D004464:Econazole; D011493:Protein Kinase C; D054467:Phospholipases A2; C063159:1-(2-(3-(4-methoxyphenyl)propoxy)-4-methoxyphenylethyl)-1H-imidazole; D009543:Nifedipine; C016392:3,3'-diindolylmethane; D002118:Calcium; D016257:Fura-2