benzyloxycarbonylvalyl-alanyl-aspartyl-fluoromethyl-ketone and Amyotrophic-Lateral-Sclerosis

Amyotrophic lateral sclerosis (ALS) is an adult-onset degenerative disorder characterised by the death of motor neurons in the cortex, brainstem, and spinal cord; resulting in progressive muscle weakness, atrophy, and death from respiratory paralysis, usually within 3-5 years of symptom onset. Approximately 10% of ALS cases are familial (FALS). Mutations in superoxide dismutase-1 (SOD1) cause approximately 20% of FALS cases and there is overwhelming evidence that a toxic gain of function is the cause of the disease. We have previously shown that FALS-associated SOD1 disease mutants enhanced neuronal death in response to a wide range of stimuli tested whereas wt-SOD1 protected against all insults. We demonstrate for the first time that over-expression of either heat shock protein Hsp27 or Hsp70 has a protective effect against SOD1 disease associated mutant-induced cell death. However, over-expression of Hsp27 and Hsp70 together has a greater potent anti-apoptotic effect, than when expressed singly, against the damaging effects of mutant SOD1. Our results indicate that FALS-associated SOD1 disease mutants possess enhanced death-inducing properties and lead to increased apoptosis which can be prevented by either the use of specific caspase inhibitors or Hsp27 and/or Hsp70 over-expression. This potent protective effect of Hsp27 and Hsp70 against the FALS-associated SOD1 disease mutants may be of potential therapeutic importance.

Topics: Amino Acid Chloromethyl Ketones; Amyotrophic Lateral Sclerosis; Analysis of Variance; Animals; Animals, Newborn; Blotting, Western; Cell Death; Cells, Cultured; Cricetinae; Culture Media, Serum-Free; Disease Models, Animal; Drug Combinations; Drug Interactions; Enzyme Inhibitors; Ganglia, Spinal; Genetic Vectors; Green Fluorescent Proteins; Heat-Shock Proteins; HIV-1; HSP27 Heat-Shock Proteins; HSP70 Heat-Shock Proteins; In Situ Nick-End Labeling; Mutagenesis; Mutation; Neoplasm Proteins; Neurons; Neuroprotective Agents; Rats; Staurosporine; Superoxide Dismutase; Superoxide Dismutase-1; Time Factors; Transfection

Mutations in the copper/zinc superoxide dismutase (SOD1) gene produce an animal model of familial amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. To test a new therapeutic strategy for ALS, we examined the effect of caspase inhibition in transgenic mice expressing mutant human SOD1 with a substitution of glycine to alanine in position 93 (mSOD1(G93A)). Intracerebroventricular administration of zVAD-fmk, a broad caspase inhibitor, delays disease onset and mortality. Moreover, zVAD-fmk inhibits caspase-1 activity as well as caspase-1 and caspase-3 mRNA up-regulation, providing evidence for a non-cell-autonomous pathway regulating caspase expression. Caspases play an instrumental role in neurodegeneration in transgenic mSOD1(G93A) mice, which suggests that caspase inhibition may have a protective role in ALS.

Topics: Amino Acid Chloromethyl Ketones; Amino Acid Substitution; Amyotrophic Lateral Sclerosis; Animals; Apoptosis; Caspase 1; Caspase 3; Caspase Inhibitors; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Disease Progression; Enzyme Activation; Gene Expression Regulation, Enzymologic; Humans; Injections, Intraventricular; Interleukin-1; Male; Mice; Mice, Transgenic; Motor Neurons; Nerve Degeneration; Neuroprotective Agents; Psychomotor Performance; Spinal Cord; Superoxide Dismutase; Superoxide Dismutase-1

Topics: Amino Acid Chloromethyl Ketones; Amyotrophic Lateral Sclerosis; Animals; Apoptosis; Caspase 1; Caspase 3; Caspase Inhibitors; Caspases; Cysteine Proteinase Inhibitors; Disease Models, Animal; Humans; Interleukin-1; Mice; Mice, Transgenic; Motor Neurons; Neuroprotective Agents; Spinal Cord; Superoxide Dismutase; Superoxide Dismutase-1