Butylated hydroxyanisole inhibits tumor necrosis factor-induced cytotoxicity and arachidonic acid release.
The mechanisms by which the antioxidant butylated hydroxyanisole (BHA) inhibits recombinant tumor necrosis factor alpha (rTNF-alpha)-induced cytotoxicity have been studied in WEHI 164 clone 13 (WEHI) and L929 fibrosarcoma cells. When BHA was added simultaneously with rTNF-alpha, it completely inhibited rTNF-alpha cytotoxicity in the WEHI and L929 cells. BHA also inhibited the toxicity when added 2 h after rTNF-alpha in WEHI cells, suggesting that BHA inhibits some late intracellular event(s) in rTNF-alpha cytotoxicity. Pretreating WEHI cells with BHA for 4 h did not decrease the binding of rTNF-alpha to its receptors as measured using flow cytometry. BHA inhibited rTNF-alpha toxicity in the presence of actinomycin D and cycloheximide, indicating that neither mRNA nor protein synthesis is necessary for the BHA effect. The antioxidant butylated hydroxytoluene (BHT) and indomethacin did not inhibit the rTNF-alpha-induced cytotoxicity nor the rTNF-alpha-induced release of [3H]arachidonic acid. By comparison, BHA completely inhibited the rTNF-alpha-induced release of arachidonic acid, suggesting that BHA somehow inhibits rTNF-alpha-induced activation of phospholipase(s). In WEHI cells, rTNF-alpha increased the level of protein-associated thiobarbituric acid reactive substances (TBARS) dose-dependently. BHA, but not BHT, blocked rTNF-alpha-induced cytotoxicity and rTNF-alpha-induced accumulation of protein-associated TBARS, suggesting that rTNF-alpha cytotoxicity is correlated with protein-associated TBARS. In conclusion, the results suggest that BHA blocks some post receptor event in rTNF-alpha-induced cytotoxicity, and that activation of phospholipase(s) coupled with the enzymatic formation of specific oxidized lipids could be a pivotal event in rTNF-alpha-induced cytotoxicity.
Brekke
O L
OL
Department of Clinical Chemistry, University of Trondheim, Norway.
Espevik
T
T
Bjerve
K S
KS
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D002083:Butylated Hydroxyanisole / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects*; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005354:Fibrosarcoma; D007213:Indomethacin / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D011994:Recombinant Proteins / Q000037:antagonists & inhibitors / Q000633:toxicity; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000633:toxicity*; D014810:Vitamin E / Q000494:pharmacology
D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D014810:Vitamin E; D003609:Dactinomycin; D002083:Butylated Hydroxyanisole; D016718:Arachidonic Acid; D003513:Cycloheximide; D007213:Indomethacin