Cytotoxicity and apoptosis induction by butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT).

Abstract

The cytotoxicity and apoptosis-inducing activity of butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and 2-tert-butyl-4-methylphenol (BMP) and the mixture of BHA and BHT (BHA/BHT) (1:1, molar ratio) were investigated, using human promeylocytic leukemia cell lines (HL-60) and human squamous cell carcinoma cell lines (HSC-2). The 50% cytotoxic concentration (CC50) declined in the order of BHA, BHT (0.2-0.3 mM) > BHA/BHT (0.04-0.07 mM) > BMP (0.02-0.05 mM). The addition of antioxidants (N-acetyl-Lcysteine, sodium ascorbate, catalase) reduced the cytotoxicity of BHA/BHT or BMP against HSC-2 cells, but not that of BHA or BHT, whereas the addition of NADH, a quinone reductase to BMP, enhanced the cytotoxicity. These findings suggested that the cytotoxicity of BHA/BHT and BMP might be caused by reactive intermediates. BHA-induced cytotoxicity was enhanced by horseradish peroxidases, suggesting that BHA was oxidizable and produced cytotoxic BHA radicals. Internucleosomal DNA fragmentation of HL-60 cells was preferably induced by BHA/BHT and BMP, followed by BHA. The MnSOD mRNA expression in HL-60 cells assayed by reverse transcriptase-polymerase chain reaction was highly inhibited by BHA/BHT or BMP, accompanied by the change in the electrophoretic mobility of MnSOD on polyacryamide gel. These compounds activated caspase-3, 8 and 9 in HL-60 cells. Activations of caspases, particularly caspase-3, declined in the order of BHA/BHT > BHA > BMP > BHT. The most cytotoxic BMP activated caspase-3 activity to the least extent, possibly in part due to the occurrence of necrosis. The great cytotoxicity and apoptosis induction by BHA/BHT may be due to reactive intermediates derived from the interaction between BHA phenoxyl radical and BHT or BHT phenoxyl radical.

• Authors: Masatoshi Saito, Hiroshi Sakagami, Seiichiro Fujisawa
• Journal: Anticancer research (Anticancer Res) 2003 Nov-Dec Vol. 23 Issue 6C Pg. 4693-701 ISSN: 0250-7005 [Print] Greece
• PMID: 14981915 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antioxidants
• Carcinogens
• RNA, Messenger
• NAD
• Butylated Hydroxytoluene
• Butylated Hydroxyanisole
• Superoxide Dismutase

Topics

• Antioxidants (toxicity)
• Apoptosis (drug effects)
• Butylated Hydroxyanisole (toxicity)
• Butylated Hydroxytoluene (toxicity)
• Carcinogens (toxicity)
• Carcinoma, Squamous Cell
• Cell Survival (drug effects)
• Gene Expression Regulation, Neoplastic (drug effects)
• HL-60 Cells
• Humans
• NAD (pharmacology)
• Polymerase Chain Reaction
• RNA, Messenger (genetics)
• Superoxide Dismutase (genetics)
• Tumor Cells, Cultured