5-fluorouracil-induced oligodendrocyte death and inhibitory effect of cycloheximide, Trolox, and Z-VAD-FMK in murine cortical culture.
BACKGROUND
5-fluorouracil (5-FU) is a widely used anticancer drug. One of the adverse effects of this drug is selective cerebral white matter injury, but to the authors' knowledge its mechanism has not been well documented. The current study was performed to investigate the mechanism of cerebral white matter injury caused by 5-FU and to develop the intervention to attenuate its injury in vitro.


METHODS
Mixed oligodendrocyte/astrocyte cells were dissociated from specimens taken from approximately 2-day-old postnatal mouse cortex and cultured for 3-4 weeks. The culture cells were exposed to 5-FU, cycloheximide, emetine, Z-VAD-fmk, 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)-quinoxaline (NBQX), Trolox, and epigallocatechin gallate. Oligodendrocyte cell death was assessed by counting the number of viable galactocerebroside-positive cells per x 100 field.


RESULTS
Mixed oligodendrocyte/astrocyte culture cells that were exposed to 5-FU (at doses of 10 microM, 30 microM, and 100 microM) for 24 hours ensued concentration-dependent oligodendrocyte death. The majority of oligodendrocytes, but few astrocytes, were injured by 100 microM 5-FU. Trolox, a vitamin E analog antioxidant, as well as cycloheximide (a protein synthesis inhibitor) and Z-VAD-fmk (a caspase inhibitor), significantly attenuated the 5-FU-induced oligodendrocyte death. However, NBQX, an alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazolepropionic acid (AMPA) receptor antagonist, did not appear to effect the 5-FU-induced oligodendrocyte death.


CONCLUSIONS
The findings of the current study suggested that 5-FU led to oligodendrocyte death rather than astrocyte death by way of the apoptotic process, whereas antioxidants may prevent the 5-FU-induced oligodendrocyte cell death in vitro.
Cho
Ki-Hyun
KH
Department of Neurology, Chonnam National University Medical School, Chonnam National University Research Institute of Medical Science, Gwangju, South Korea.
Choi
Sung-Min
SM
Kim
Byeong-Chae
BC
Lee
Seung-Han
SH
Park
Man-Seok
MS
Kim
Myeong-Kyu
MK
Kim
Jong-Keun
JK
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology*; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology* / Q000633:toxicity; D000975:Antioxidants / Q000494:pharmacology; D061945:Caspase Inhibitors; D018929:Cell Culture Techniques; D016923:Cell Death / Q000187:drug effects; D002839:Chromans / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005472:Fluorouracil / Q000494:pharmacology* / Q000633:toxicity; D051379:Mice; D009836:Oligodendroglia / Q000187:drug effects*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011810:Quinoxalines / Q000494:pharmacology; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors
D000590:Amino Acid Chloromethyl Ketones; D000964:Antimetabolites, Antineoplastic; D000975:Antioxidants; D061945:Caspase Inhibitors; D002839:Chromans; D015853:Cysteine Proteinase Inhibitors; D018691:Excitatory Amino Acid Antagonists; D011500:Protein Synthesis Inhibitors; D011810:Quinoxalines; D018091:Receptors, AMPA; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline; D003513:Cycloheximide; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D005472:Fluorouracil