Treatment with an S1R agonist, PRE-084, improved locomotor function and motor neuron survival in presymptomatic and early-symptomatic mutant SOD1G93A mice, resembling the neuroprotective effects previously tested in vitro [ 71].
The present results demonstrate the reversibility of synaptic and behavioral phenotypes associated with abnormal breathing in symptomatic Mecp2 mutant mice, a model of RTT.
In summary, the large collection of symptomatic double-mutant mouse lines has greatly expanded the armory of potential mouse models for preclinical studies.
Interestingly, the authors found an increase in a-synuclein levels via immunoblot and immunohistochemistry in the substantia nigra (SN) of symptomatic a-synuclein mutant transgenic mice.
In animal models of PD, tauopathic changes have been observed in brainstem of symptomatic A30P α-Syn mutant mice at pSer202 and pSer396/404 [38].
Such mutations are more likely to occur during the secondary stage of symptomatic infection, as resistant mutants in viruses isolated from treated patients were mostly detected 3 days after the onset of treatment [19], [20].
The association between aggregation of mutant SOD1 and symptomatic disease duration, rather than onset, is a particularly intriguing finding.
Importantly, the relative aggregation index of WT hSOD1 protein in all of the WT SOD1 lines of mice was not as high as mutant G37R hSOD1 in symptomatic G37R Line 29 hSOD1 mice [genomic hSOD1 construct (16)] (Gn.G37R, Fig. 2A and B), which develop disease at ∼7 months of age and which accumulate relatively low levels of aggregated hSOD1 at disease endstage (6).
In this study, we extracted lipids from spinal cord and skeletal muscle of mutant SOD1 mice at pre-symptomatic and symptomatic stages.
In the spinal cord of G93A SOD1 mutant mice at the symptomatic stage, neuronal LBHI show GRP78/BiP immunoreactive, suggesting the involvement of ER resident protein [28].
Symptomatic mice co-expressing WT and mutant SOD1 accumulate detergent-insoluble aggregates of both proteins regardless of whether the age to paralysis is altered.
