靶向线粒体的肽可减轻实验性肾血管性高血压逆转后残余的心肌损伤。
Mitochondrial targeted peptides attenuate residual myocardial damage after reversal of experimental renovascular hypertension.
机构信息
aDivision of Nephrology and Hypertension, Department of Internal Medicine bDivision of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
出版信息
J Hypertens. 2014 Jan;32(1):154-65. doi: 10.1097/HJH.0b013e3283658a53.
BACKGROUND
Renovascular hypertension (RVHT) increases cardiovascular morbidity and mortality. Renal revascularization with percutaneous transluminal renal angioplasty and stenting (PTRS) may reverse RVHT but may not fully regress cardiac remodeling and damage, possibly due to persistent myocardial insults. Bendavia is a mitochondrial targeted peptide that reduces ischemic cardiomyopathy by improving mitochondrial function. However, its potential for attenuating residual myocardial damage after reversal of RVHT has not been explored. We hypothesized that treatment with Bendavia as an adjunct to PTRS would improve cardiac function and oxygenation, and decrease myocardial injury in swine RVHT.
METHODS AND RESULTS
After 6 weeks of RVHT (unilateral renal artery stenosis) or control, pigs underwent PTRS (or sham), with adjunct continuous infusion of Bendavia (0.05 mg/kg intravenously, 30 min before to 3.5 h after PTRS) or vehicle (n = 7 each). Four weeks later, systolic and diastolic function were assessed by multidetector computed tomography, myocardial oxygenation by blood oxygen level-dependent MRI, and myocardial morphology, apoptosis, mitochondrial biogenesis, and fibrosis evaluated ex vivo. PTRS restored blood pressure in both groups, yet E/A ratio remained decreased. Myocardial oxygenation and mitochondrial biogenesis improved, and myocardial inflammation, oxidative stress, and fibrosis normalized in association with improvement in diastolic function in RVHT + PTRS + Bendavia animals.
CONCLUSION
Adjunct Bendavia during PTRS in swine RVHT improved diastolic function and oxygenation and reversed myocardial tissue damage. This approach may allow a novel strategy for preservation of cardiac function and structure in RVHT.
背景
肾血管性高血压 (RVHT) 增加心血管发病率和死亡率。经皮腔内肾血管成形术和支架置入术 (PTRS) 肾血管重建可能逆转 RVHT,但可能无法完全逆转心脏重构和损伤,这可能是由于持续的心肌损伤。Bendavia 是一种靶向线粒体的肽,可通过改善线粒体功能来减轻缺血性心肌病。然而,其在逆转 RVHT 后减轻残余心肌损伤的潜力尚未得到探索。我们假设 Bendavia 作为 PTRS 的辅助治疗可以改善心脏功能和氧合,并减少猪 RVHT 中的心肌损伤。
方法和结果
在 RVHT(单侧肾动脉狭窄)或对照 6 周后,猪接受 PTRS(或假手术),同时辅助连续静脉输注 Bendavia(0.05 mg/kg,PTRS 前 30 分钟至 3.5 小时)或载体(每组 7 只)。4 周后,通过多排螺旋 CT 评估收缩和舒张功能,通过血氧水平依赖性 MRI 评估心肌氧合,通过体外评估心肌形态、凋亡、线粒体生物发生和纤维化。PTRS 恢复了两组的血压,但 E/A 比值仍然降低。心肌氧合和线粒体生物发生改善,心肌炎症、氧化应激和纤维化在 RVHT+PTRS+Bendavia 动物舒张功能改善的同时恢复正常。
结论
在猪 RVHT 的 PTRS 中辅助 Bendavia 改善了舒张功能和氧合,并逆转了心肌组织损伤。这种方法可能为 RVHT 提供一种保护心脏功能和结构的新策略。