The distribution of the inositol phosphatase SHIP1 in a murine model of Amyotrophic Lateral Sclerosis (ALS)

Src homology 2 domain-containing inositol-5’ phosphatase (SHIP1) is a protein which suppresses the activation, proliferation, and survival of hematopoietic cells. Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the degeneration of specific neuron populations which leads to atrophy of skeletal muscles, paralysis, and death. Microgliosis is a common hallmark in ALS patients and in mouse models having over-expression of SOD1 (mSOD1); however, the association between microgliosis and disease progression has not yet been determined. Using immunohistochemistry (IHC), SHIP1 expression in macrophages and microglia was investigated in the lumbar spinal cord of control and mSOD1 mice at 3 time points: 11 weeks (asymptomatic), 15 weeks (symptomatic), and 18 weeks (advanced stage). A significant increase in SHIP1 immunoreactivity was found between control mice and diseased mice at symptomatic and advanced stages. SHIP1 immunoreactivity also significantly increased throughout disease progression suggesting that SHIP1 is involved in regulating microgliosis in ALS.