Gp. Lim et al., MATRIX METALLOPROTEINASES IN THE NEOCORTEX AND SPINAL-CORD OF AMYOTROPHIC-LATERAL-SCLEROSIS PATIENTS, Journal of neurochemistry, 67(1), 1996, pp. 251-259
Matrix metalloproteinases (MMPs) were analyzed by immunohistochemistry
and zymography in amyotrophic lateral sclerosis (ALS) and control bra
in and spinal cord specimens, Three major bands of enzyme activity (70
, 100, and 130 kDa) were consistently observed and were subsequently i
dentified as MMP-2 (70 kDa; also known as EC 3.4.24.24 or gelatinase A
) and MMP-9 (100 and 130 kDa; also known as EC 3.4.24.35 or gelatinase
B), Immunohistochemical studies established the presence of MM P-2 in
astrocytes and MMP-9 in pyramidal neurons in the motor cortex and mot
or neurons in the spinal cord of ALS patients. Although a significant
decrease in MMP-2 activity was noticed in the ALS motor cortex, statis
tically significant increases in MMP-9 (100-kDa) activity were observe
d in ALS frontal and occipital cortices (BA10 and 17) and all three sp
inal cord regions when compared with control specimens. The highest MM
P-9 (100-kDa) activities in ALS were found in the motor cortex and tho
racic and lumbar cord specimens. The abnormally high amount of MMP-9 a
nd its possible release at the synapse may destroy the structural inte
grity of the surrounding matrix, thereby contributing to the pathogene
sis of ALS.