Rikimaru Mitsue, Ohsawa Yutaka, Wolf Alexander M, Nishimaki Kiyomi, Ichimiya Harumi, Kamimura Naomi, Nishimatsu Shin-ichiro, Ohta Shigeo, Sunada Yoshihide
Department of Neurology, Kawasaki Medical School, Japan.
Intern Med. 2012;51(24):3351-7. doi: 10.2169/internalmedicine.51.7529. Epub 2012 Dec 15.
Post-transcriptional taurine modification at the first anticodon ("wobble") nucleotide is deficient in A3243G-mutant mitochondrial (mt) tRNA(Leu(UUR)) of patients with myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). Wobble nucleotide modifications in tRNAs have recently been identified to be important in the accurate and efficient deciphering of codons. We herein examined whether taurine can alleviate mitochondrial dysfunction in patient-derived pathogenic cells and prevent clinical symptoms in MELAS patients.
The addition of taurine to the culture media ameliorated the reduced oxygen consumption, decreased the mitochondrial membrane potential, and increased the oxidative stress in MELAS patient-derived cells. Moreover, high dose oral administration of taurine (0.25 g/kg/day) completely prevented stroke-like episodes in two MELAS patients for more than nine years.
Taurine supplementation may be a novel potential treatment option for preventing the stroke-like episodes associated with MELAS.
在患有肌病、脑病、乳酸性酸中毒和卒中样发作(MELAS)的患者中,A3243G突变的线粒体(mt)tRNA(Leu(UUR))在第一个反密码子(“摆动”)核苷酸处的转录后牛磺酸修饰存在缺陷。最近已确定tRNA中的摆动核苷酸修饰对于准确、高效地解读密码子很重要。我们在此研究了牛磺酸是否可以减轻患者来源的致病细胞中的线粒体功能障碍,并预防MELAS患者的临床症状。
在培养基中添加牛磺酸可改善MELAS患者来源细胞中降低的耗氧量,降低线粒体膜电位,并增加氧化应激。此外,高剂量口服牛磺酸(0.25 g/kg/天)在两名MELAS患者中完全预防了卒中样发作超过九年。
补充牛磺酸可能是预防与MELAS相关的卒中样发作的一种新的潜在治疗选择。