Apoptosis signals in sporadic amyotrophic lateral sclerosis: an immunocytochemical study

Sporadic amyotrophic lateral sclerosis (sALS) is a neurodegenerative disord er of unknown cause characterized by selective loss of both upper and lower motor neurons. Whether neuronal death in sALS is due to apoptosis has so f ar not been clarified. In this study, the expression and distribution patte rns of pro- and anti-apoptotic bcl-2 family members as well as the executio ner caspase-3 were investigated in post-mortem CNS tissue of eight sALS pat ients and seven age-matched controls. Sparse motor neurons were immunoreact ive for bcl-2, bax, bak, and CM1 on serial sections through the spinal cord and motor cortex of individual sALS patients and controls. However, there was no obvious difference in the numbers of immunoreactive JR) neurons betw een the two groups. The study did not find evidence for apoptosis as a majo r mechanism of motor neuronal cell death in sALS.