Alterations in reactive oxygen, ph and calcium in astrocytoma cells
during lethal injury.
Wu, Yankuan, Bruce M. Taylor, and Frank F. Sun.
Department of Cell Biology and Inflammation Research, Upjohn
Laboratories, Kalamazoo, MI 49001
APStracts 2:0257C, 1995.
Exposure of the cultured human astrocytoma cells to iodoacetic acid
(IAA) results in rapid depletion of cellular ATP and cell death.
Pathophysiological changes in the injured cells including formation
of reactive oxygen species (ROS), cell viability, glutathione, pH,
and cytosolic calcium were characterized at the cellular level via
fluorescence microscopy. After IAA treatment, cellular ATP and
intracellular GSH fell sharply to undetectable levels within two
hours. ROS as detected by the oxidation of dichlorofluorescin,
appeared in 20 minutes and reached a maximum prior to the loss of
membrane integrity. Cells became acidotic within 10 minutes.
Cytosolic free calcium concentration exhibited a slow increase,
followed by a sharp influx shortly before the rupture of the cell
membrane. The addition of lipophilic antioxidants
nordihydroguaiaretic acid or the troloxamine, U-78517F eliminated the
accumulation of ROS and delayed the onset of cell death without
affecting other parameters observed in the early phase of the injury.
We conclude that ROS is formed and may play important roles during
lethal cell injury caused by energy depletion.
Received 17 January 1995; accepted in final form 6 July 1995.
APS Manuscript Number C31-5.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 18 July 1995.