2017 年 34 巻 2 号 p. 86-94
Both TAR DNA binding protein of 43kDa (TDP–43) pathology and failure of RNA editing at the glutamine/arginine (Q/R) site of GluA2, a subunit of the α–amino–3–hydroxy–5–methyl–4–isoxazole propionic acid (AMPA) receptor, are the characteristic etiology–linked molecular abnormalities that concomitantly occur in the motor neurons of the majority of patients with amyotrophic lateral sclerosis (ALS), the most common adult–onset fatal motor neuron disease. Adenosine deaminase acting on RNA 2 (ADAR2) specifically catalyzes RNA editing at the Q/R site of GluA2, and conditional ADAR2 knockout mice (ADAR2flox/flox/VAChT–Cre.Fast ; AR2 mice) exhibit a progressive ALS phenotype with TDP–43 pathology–like TDP–43 mislocalization in the ADAR2–lacking motor neurons. Because Ca2+–permeable AMPA receptor–mediated mechanism underlies death of motor neurons in the AR2 mice, amelioration of exaggerated Ca2+ influx by AMPA receptor antagonists may be a potential ALS therapy. Here we showed that oral perampanel, a selective non–competitive AMPA receptor antagonist, significantly prevented progression of ALS phenotype and death of motor neurons with effective normalization of TDP–43 pathology in the AR2 mice. Given that perampanel has already been approved as an anti–epileptic drug, perampanel would be a potential candidate ALS drug.
