Koganti Siva Rama Krishna, Zhu Zhiyong, Subbotina Ekaterina, Gao Zhan, Sierra Ana, Proenza Manuel, Yang Liping, Alekseev Alexey, Hodgson-Zingman Denice, Zingman Leonid
Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.
Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.
Mol Ther. 2015 Apr;23(4):707-16. doi: 10.1038/mt.2015.21. Epub 2015 Feb 4.
Despite the medical, social, and economic impact of obesity, only a few therapeutic options, focused largely on reducing caloric intake, are currently available and these have limited success rates. A major impediment is that any challenge by caloric restriction is counterbalanced by activation of systems that conserve energy to prevent body weight loss. Therefore, targeting energy-conserving mechanisms to promote energy expenditure is an attractive strategy for obesity treatment. Here, in order to suppress muscle energy efficiency, we target sarcolemmal ATP-sensitive potassium (KATP) channels which have previously been shown to be important in maintaining muscle energy economy. Specifically, we employ intramuscular injections of cell-penetrating vivo-morpholinos to prevent translation of the channel pore-forming subunit. This intervention results in significant reduction of KATP channel expression and function in treated areas, without affecting the channel expression in nontargeted tissues. Furthermore, suppression of KATP channel function in a group of hind limb muscles causes a substantial increase in activity-related energy consumption, with little effect on exercise tolerance. These findings establish a proof-of-principle that selective skeletal muscle targeting of sarcolemmal KATP channel function is possible and that this intervention can alter overall bodily energetics without a disabling impact on muscle mechanical function.
尽管肥胖对医学、社会和经济都有影响,但目前可用的治疗选择很少,主要集中在减少热量摄入,而且这些方法的成功率有限。一个主要障碍是,热量限制带来的任何挑战都会被激活的能量保存系统所抵消,以防止体重减轻。因此,针对能量保存机制来促进能量消耗是一种有吸引力的肥胖治疗策略。在这里,为了抑制肌肉能量效率,我们靶向肌膜ATP敏感性钾(KATP)通道,该通道先前已被证明在维持肌肉能量代谢中很重要。具体而言,我们通过肌肉内注射细胞穿透性活体吗啉代寡核苷酸来阻止通道孔形成亚基的翻译。这种干预导致治疗区域的KATP通道表达和功能显著降低,而不影响非靶向组织中的通道表达。此外,抑制一组后肢肌肉中的KATP通道功能会导致与活动相关的能量消耗大幅增加,而对运动耐力影响很小。这些发现证明了一个原理,即选择性地靶向骨骼肌中的肌膜KATP通道功能是可行的,并且这种干预可以改变整体身体能量代谢,而不会对肌肉机械功能产生致残性影响。