Abstract:

Rimmed vacuoles in myofibers are thought to be due to the accumulation of autophagic vacuoles, and can be characteristic in certain myopathies with protein inclusions in myofibers. In this study, we performed a detailed clinical, molecular, and pathological characterization of Becker muscular dystrophy patients who have rimmed vacuoles in muscles. Among 65 Becker muscular dystrophy patients, we identified 12 patients who have rimmed vacuoles and 11 patients who have deletions in exons 45-48 in DMD gene. All patients having rimmed vacuoles showed milder clinical features compared to those without rimmed vacuoles. Interestingly, the rimmed vacuoles in Becker muscular dystrophy muscles seem to represent autophagic vacuoles and are also associated with polyubiquitinated protein aggregates. These findings support the notion that rimmed vacuoles can appear in Becker muscular dystrophy, and may be related to the chronic changes in muscle pathology induced by certain mutations in the DMD gene.

日本語要旨:

筋病理で縁取り空胞を示す12名のベッカー型筋ジストロフィー患者を見いだした。11名の患者でDMD遺伝子にエクソン45-48に欠失を持ち、臨床的には非常に軽症であった。興 味深いことにベッカー型筋ジストロフィー患者の筋線維に見られる縁 取り空胞は、自己貪食空胞とユビキチン化タンパク質の蓄積等、他の封入体ミオバチーのものと同様の性質を示した。