Jl. Bonheur et al., TRAUMATIC INJURY OF SPINAL-CORD CELLS IN-VITRO REDUCED BY GM1 GANGLIOSIDE, Restorative neurology and neuroscience, 6(2), 1994, pp. 127-133
GM1 ganglioside (monosialoganglioside) is a significant endogenous com
ponent of central nervous system (CNS) cellular membranes, thereby con
tributing to the membranes' integrity and function. Exogenous ganglios
ides have been shown to be incorporated into plasma membranes and can
exert neuroprotective effects on damaged neuronal tissue(s). An in vit
ro method of physical injury (trauma) previously described which used
cultures derived from fetal mouse spinal cord [38] was adapted for the
se studies in order for us to assess GM1's neuroprotective efficacy. I
njury was induced by uniformly crosshatching the spinal cell cultures
with a 1 mm plastic pipette tip. The extent of injury and the effects
of GM1 ganglioside posttreatment (80 mu M) was assessed after 48 h by
measuring lactate dehydrogenase (LDH) released and by observing change
s in the plasma membrane surface distribution of endogenous GM1 using
cholera toxin/antitoxin/fluorescent antibody immunohistochemistry. A g
radient of injury, from the zone of maximum injury to partially trauma
tized or non-injured areas, was seen using immunohistochemistry. The p
rimary injury zone in this gradient was characterized by areas of swol
len or dead cells and abnormal or degenerating cell processes. At furt
her distances, cells were observed to be nearly normal, with intact fi
bers. This gradient of injury may reflect proximate (at the locus of t
rauma) and distant effects of the release of neurotoxic levels of endo
genous glutamate (Glu) and other excitatory amino acids. Ganglioside G
M1 treatment resulted in a significantly reduced (>75%) release of LDH
as well as enhanced cell and process integrity indicative of reduced
tissue injury. These initial results indicate that GM1's previously do
cumented neuroprotective effects using neuronal culture systems can be
generalized to injured spinal cells in vitro wherein there is evidenc
e for preservation (rescue) of cellular plasma membranes after injury
as reflected by reduced cell loss, swelling, and process degeneration,
as well as decreased LDH release.