Background: and Purpose Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease. Selective deficiency of edited adenosine deaminase acting on RNA 2 (ADAR2), a key molecule in the acquisition of Ca 2+ resistance in motor neurons, has been reported in sporadic ALS (sALS) spinal motor neurons. Since ADAR2 activity is positively regulated by prolyl isomerase Protein never in mitosis gene A interacting-1 (Pin1), a known phosphorylation-dependent peptidyl-prolyl cis/trans isomerase, we investigated Pin1 expression in spinal motor neurons in sALS. Methods: Specimens of the spinal cord were obtained from the lumbar region in eight sALS patients and age-matched five controls after postmortem examinations. The specimens were double stained with anti-Pin1 and anti-TAR DNA-binding protein of 43 kDa (TDP-43) antibodies, and examined under a fluorescence microscope. Results: This study analyzed 254 and 422 spinal motor neurons from 8 sALS patients and 5 control subjects, respectively. The frequency of motor neurons with high cytoplasmic Pin1 expression from the spinal cord did not differ significantly between sALS specimens without cytoplasmic TDP-43 inclusions and control specimens. However, in sALS specimens, neurons for which the Pin1 immunoluminescence intensity in the cytoplasm was at least twice that in the background were more common in specimens with cytoplasmic TDP-43 inclusions (p<0.05 in χ 2 test). Conclusions In sALS, neurons with higher expression levels of Pin1 levels had more TDP-43 inclusions. Despite the feedback mechanism between Pin1 and ADAR2 being unclear, since Pin1 positively regulates ADAR2, our results suggest that higher Pin1 expression levels in motor neurons with TDP-43 pathology from sALS patients represent a compensatory mechanism.

Background: and Purpose To clarify the effect of perampanel (PER) on sporadic amyotrophic lateral sclerosis (sALS) progression, the relationship between the changes in Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) scores and serum PER concentrations was investigated. Methods: 12 patients with sALS from our hospital who agreed to participate and completed the PER for sALS randomized phase 2 study were included. After completing the study, we retrospectively obtained serum PER concentration data from the patients. Based on their mean PER concentrations, we divided the patients who had been taking PER into two groups:four patients with a mean PER concentration of ≥400 ng/mL were assigned to the H group, and three with a mean PER concentration of <400 ng/mL were assigned to the L group. The control group consisted of five patients who had been taking a placebo. We obtained the ALSFRS-R scores of each patient at 36 and 48 weeks after randomization. The differences in ALSFRS-R scores at baseline (0 weeks) and each subsequent week were used in the analysis. Results: At 48 weeks, there were no differences in the degree of deterioration of the bulbar, upper and lower limb, and respiratory ALSFRS-R subscores and total ALSFRS-R score. However, at 36 weeks, the bulbar subscore was significantly lower in the H group than in the control group (p=0.032). Conclusions Because high PER concentrations may exacerbate bulbar symptoms in patients with sALS, serum PER measurements may be beneficial when patients with sALS are taking PER.