Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, 61 Queen Street East, Toronto, ON, M5C 2T2, Canada.
Cardiovasc Diabetol. 2018 Jul 7;17(1):99. doi: 10.1186/s12933-018-0741-9.
Inhibiting both type 1 and 2 sodium-glucose linked cotransporter (SGLT1/2) offers the potential to not only increase glucosuria beyond that seen with selective SGLT2 inhibition alone but to reduce glucose absorption from the gut and to thereby also stimulate glucagon-like peptide 1 secretion. However, beyond the kidney and gut, SGLT1 is expressed in a range of other organs particularly the heart where it potentially assists GLUT-mediated glucose transport. Since cardiac myocytes become more reliant on glucose as a fuel source in the setting of stress, the present study sought to compare the effects of dual SGLT1/2 inhibition with selective SGLT2 inhibition in the normal and diseased heart.
Fischer F344 rats underwent ligation of the left anterior descending coronary artery or sham ligation before being randomized to receive the dual SGLT1/2 inhibitor, T-1095, the selective SGLT2 inhibitor, dapagliflozin or vehicle. In addition to measuring laboratory parameters, animals also underwent echocardiography and cardiac catheterization to assess systolic and diastolic function in detail.
When compared with rats that had received either vehicle or dapagliflozin, T-1095 exacerbated cardiac dysfunction in the post myocardial infarction setting. In addition to higher lung weights, T-1095 treated rats had evidence of worsened systolic function with lower ejection fractions and reduction in the rate of left ventricle pressure rise in early systole (dP/dt). Diastolic function was also worse in animals that had received T-1095 with prolongation of the time constant for isovolumic-pressure decline (Tau) and an increase in the end-diastolic pressure volume relationship, indices of the active, energy-dependent and passive phases of cardiac relaxation.
The exacerbation of post myocardial infarction cardiac dysfunction with T-1095 in the experimental setting suggests the need for caution with the use of dual SGLT1/2 inhibitors in humans.
抑制 1 型和 2 型钠-葡萄糖协同转运蛋白(SGLT1/2)不仅有可能增加尿糖排泄,超过单独选择性 SGLT2 抑制所看到的程度,而且还可以减少肠道葡萄糖吸收,从而刺激胰高血糖素样肽 1 的分泌。然而,除了肾脏和肠道,SGLT1 在一系列其他器官中表达,特别是在心脏中,它可能有助于 GLUT 介导的葡萄糖转运。由于心肌细胞在应激状态下对葡萄糖作为燃料源的依赖性增加,本研究旨在比较双重 SGLT1/2 抑制与选择性 SGLT2 抑制在正常和患病心脏中的作用。
Fischer F344 大鼠在左前降支冠状动脉结扎或假结扎后,随机接受双重 SGLT1/2 抑制剂 T-1095、选择性 SGLT2 抑制剂达格列净或载体治疗。除了测量实验室参数外,动物还进行了超声心动图和心导管检查,以详细评估收缩和舒张功能。
与接受载体或达格列净治疗的大鼠相比,T-1095 在心肌梗死后加重了心脏功能障碍。除了肺重增加外,T-1095 治疗的大鼠收缩功能恶化,射血分数降低,早期收缩时左心室压力上升率(dP/dt)降低。接受 T-1095 治疗的动物舒张功能也较差,等容压力下降时间常数(Tau)延长,舒张末期压力-容积关系增加,这些都是心脏舒张主动、能量依赖和被动阶段的指标。
在实验环境中,T-1095 加重心肌梗死后心脏功能障碍的现象表明,在人类中使用双重 SGLT1/2 抑制剂需要谨慎。