Effect of melatonin, piperonyl butoxide, or cobalt chloride on L-cysteine-induced lipid peroxidation in homogenate from whole brain of mice.
Brain homogenates exposed to a low concentration of L-cysteine (0.05, 0.1, 0.5, 1.0, and 2.0 mM) were significantly increased in their concentration of malondialdehyde (MDA) + 4-hydroxyalkenals (4-HDA) as compared to control samples, in a concentration-dependent manner. The increased lipid peroxidation by L-cysteine was attenuated or completely abolished by co-incubation with melatonin (2 mM), a potent free radical scavenger, piperonyl butoxide (1 mM), an inhibitor of mixed function oxidase, or cobalt chloride (0.01, 0.02 or 0.05 mM), another inhibitor of mixed function oxidase, but not allopurinol (0.1 mM), an inhibitor of xanthine oxidase. In addition, when a brain homogenate heated at 85 degrees C for 1 min was incubated with or without L-cysteine at 37 degrees C for 20 min, MDA + 4-HDA levels in the homogenate was not changed between L-cysteine and control. These results suggest that L-cysteine-induced lipid peroxidation may be involved in the enzymatic mixed function oxidation systems in brain.
Yamamoto
H
H
Institute of Community Medicine, University of Tsukuba, Ibaraki, Japan. ves00011@niftyserve.or.jp
Tang
H W
HW
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D003035:Cobalt / Q000494:pharmacology*; D003545:Cysteine; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D008550:Melatonin / Q000494:pharmacology*; D051379:Mice; D006899:Mixed Function Oxygenases / Q000187:drug effects / Q000378:metabolism; D010882:Piperonyl Butoxide / Q000494:pharmacology*; D014969:Xanthine Oxidase / Q000187:drug effects / Q000378:metabolism
D004791:Enzyme Inhibitors; D003035:Cobalt; D008315:Malondialdehyde; D006899:Mixed Function Oxygenases; D014969:Xanthine Oxidase; C018021:cobaltous chloride; D008550:Melatonin; D003545:Cysteine; D010882:Piperonyl Butoxide