behavior/neurological
• mice show only mild changes in the Morris water maze, with longer latencies to the escape platform on the 3rd day of testing
|
• mice show a small, but significant, reduction in the startle amplitudes at 6 weeks of age, but the difference is no longer seen in subsequent tests
|
• hind limb clasping
|
• in the accelerating roatarod, mice show reduced latency to fall at 5 and 8 weeks of age
|
• in the wire-hang task, mice show reduced latency to fall and decreased overall coordination score at 4 and 8 weeks of age
|
• altered gait, with progressive severity as mice age
|
• mice show a reduction in rearing at 8 weeks, but not 5 weeks, of age, consistent with loss of hind limb strength
|
• mice are hyperactive in a novel environment at 5 weeks of age, showing increased general activity in the beginning intervals of test
• however, by the second test at 8 weeks of age, no differences are seen
|
cellular
• modest, but significant, decrease in the number of lysosomes in axons of cortical neurons
|
nervous system
• motor neurons within the ventral horn and sciatic nerve show Luxol Fast Blue stained spherical bodies indicating dystrophic axons
• spheroids show dense accumulations of organelles in various stages of degeneration
• swollen axons are pronounced and numerous in the spinal cord, affecting both myelinated and unmyelinated fibers
• swollen axons have tubulovesicular elements forming an anastomosing, curvilinear network of delicate membrane structures with lumens indicative of dystrophic axons
|
• neurons show decreased anterograde velocity of LAMP1-GFP-labeled lysosomes compared to controls
• neurons show reduction in both anterograde and retrograde lysosomal run length
|
reproductive system
• males exhibit decreased fertility by 15 weeks of age due to progressive loss of motor coordination
• however, sperm are able to fertilize oocytes
|
Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
hereditary spastic paraplegia | DOID:2476 |
OMIM:PS303350 |
J:271219 | |
neuroaxonal dystrophy | DOID:2367 | J:271219 |