Regular exercise prolongs survival in a type 2 spinal muscular atrophy model mouse

J Neurosci. 2005 Aug 17;25(33):7615-22. doi: 10.1523/JNEUROSCI.1245-05.2005.

Abstract

Several studies indicate that physical exercise is likely to be neuroprotective, even in the case of neuromuscular disease. In the present work, we evaluated the efficiency of running-based training on type 2 spinal muscular atrophy (SMA)-like mice. The model used in this study is an SMN (survival motor neuron)-null mouse carrying one copy of a transgene of human SMN2. The running-induced benefits sustained the motor function and the life span of the type 2 SMA-like mice by 57.3%. We showed that the extent of neuronal death is reduced in the lumbar anterior horn of the spinal cord of running-trained mice in comparison with untrained animals. Notably, exercise enhanced motoneuron survival. We showed that the running-mediated neuroprotection is related to a change of the alternative splicing pattern of exon 7 in the SMN2 gene, leading to increased amounts of exon 7-containing transcripts in the spinal cord of trained mice. In addition, analysis at the level of two muscles from the calf, the slow-twitch soleus and the fast-twitch plantaris, showed an overall conserved muscle phenotype in running-trained animals. These data provide the first evidence for the beneficial effect of exercise in SMA and might lead to important therapeutic developments for human SMA patients.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cyclic AMP Response Element-Binding Protein / biosynthesis
  • Cyclic AMP Response Element-Binding Protein / genetics
  • Disease Models, Animal*
  • Female
  • Male
  • Mice
  • Mice, Knockout
  • Mice, Transgenic
  • Motor Neurons / pathology
  • Motor Neurons / physiology
  • Nerve Tissue Proteins / biosynthesis
  • Nerve Tissue Proteins / genetics
  • Physical Conditioning, Animal / methods*
  • RNA-Binding Proteins / biosynthesis
  • RNA-Binding Proteins / genetics
  • SMN Complex Proteins
  • Spinal Muscular Atrophies of Childhood / genetics*
  • Spinal Muscular Atrophies of Childhood / mortality*
  • Spinal Muscular Atrophies of Childhood / pathology
  • Survival Rate
  • Survival of Motor Neuron 2 Protein
  • Time Factors

Substances

  • Cyclic AMP Response Element-Binding Protein
  • Nerve Tissue Proteins
  • RNA-Binding Proteins
  • SMN Complex Proteins
  • SMN2 protein, human
  • Survival of Motor Neuron 2 Protein