Mitochonic Acid 5 Binds Mitochondria and Ameliorates Renal Tubular and Cardiac Myocyte Damage

作者:Suzuki Takehiro; Yamaguchi Hiroaki; Kikusato Motoi; Hashizume Osamu; Nagatoishi Satoru; Matsuo Akihiro; Sato Takeya; Kudo Tai; Matsuhashi Tetsuro; Murayanna Kazutaka; Ohba Yuki; Watanabe Shun; Kanno Shin ichiro; Minaki Daichi; Saigusa Daisuke; Shinbo Hiroko; Mori Nobuyoshi; Yuri Akinori; Yokoro Miyuki; Mishima Eikan; Shima Hisato; Akiyama Yasutoshi; Takeuchi Yoichi; Kikuchi Koichi; Toyohara Takafumi; Suzuki Chitose; Ichimura Takaharu; Anzai Jun ichi
来源:Journal of the American Society of Nephrology, 2016, 27(7): 1925-1932.
DOI:10.1681/ASN.2015060623

摘要

Mitochondrial dysfunction causes increased oxidative stress and depletion of ATP, which are involved in the etiology of a variety of renal diseases, such as CKD, AKI, and steroid resistant nephrotic syndrome. Antioxidant therapies are being investigated, but clinical outcomes have yet to be determined. Recently, we reported that a newly synthesized indole derivative, mitochonic acid 5 (MA-5), increases cellular ATP level and survival of fibroblasts from patients with mitochondrial disease. MA-5 modulates mitochondrial ATP synthesis independently of oxidative phosphorylation and the electron transport chain. Here, we further investigated the mechanism of action for MA-5. Administration of MA-5 to an ischemia-reperfusion injury model and a cisplatin-induced nephropathy model improved renal function. In in vitro bioenergetic studies, MA-5 facilitated ATP production and reduced the level of mitochondrial reactive oxygen species (ROS) without affecting activity of mitochondrial complexes I-IV. Additional assays revealed that MA-5 targets the mitochondrial protein mitofilin at the crista junction of the inner membrane. In Hep3B cells, overexpression of mitofilin increased the basal ATP level, and treatment with MA-5 amplified this effect. In a unique mitochondrial disease model (Mitomice with mitochondria) DNA deletion that mimics typical human mitochondrial disease phenotype), MA-5 improved the reduced cardiac and renal mitochondria respiration and seemed to prolong survival, although statistical analysis of survival times could not be conducted. These results suggest that MA-5 functions in a manner differing from that of antioxidant therapy and could be a novel therapeutic drug for the treatment of cardiac and renal diseases associated with mitochondrial dysfunction.

  • 出版日期2016-7