title: Calcium channel blockers verapamil and diltiazem impaired rubratoxin B-caused toxicity in HL60 cells.
abstract: The effects of calcium channel blockers (CCBs) verapamil and diltiazem on the toxicity of rubratoxin B in HL60 cells were investigated. Treatment of rubratoxin B caused a considerable rate of blebbing, fragmentation and condensation of cells. The rate of this morphological change was much lower in the concomitant rubratoxin B and CCBs-treated cells than in the cells treated only with rubratoxin B. Cell viability was determined by measuring mitochondrial succinic dehydrogenase activity and the rate of cell proliferation. The results of these assays were of the same tendency as that of the morphological study. CCBs attenuated rubratoxin B's toxicity on cell viability because of their protective action. Rubratoxin B induced apoptosis in the presence of internucleosomal fragmentation. In contrast, concomitant rubratoxin B and CCBs treatment did not. Taken together, the above results indicated that CCBs impaired the toxicity including morphological change, cell viability and apoptosis caused by rubratoxin B.
authors.affiliation: National Food Research Institute, Ministry of Agriculture, Forestry and Fisheries, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8642, Japan. nagasima@nfri.affrc.go.jp
authors.forename: H
authors.initials: H
authors.lastname: Nagashima
authors.forename: T
authors.initials: T
authors.lastname: Goto
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D020013:Calcium Signaling / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D004110:Diltiazem / Q000494:pharmacology*; D018922:HL-60 Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D009183:Mycotoxins / Q000037:antagonists & inhibitors / Q000633:toxicity*; D014700:Verapamil / Q000494:pharmacology*
chemical_list: D002121:Calcium Channel Blockers; D009183:Mycotoxins; C100297:rubratoxins; D014700:Verapamil; D004110:Diltiazem