Cardiovascular Research Group, Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary.
Pharmahungary Group, H-6722 Szeged, Hungary.
Int J Mol Sci. 2020 Sep 23;21(19):6990. doi: 10.3390/ijms21196990.
We recently developed novel matrix metalloproteinase-2 (MMP-2) inhibitor small molecules for cardioprotection against ischemia/reperfusion injury and validated their efficacy in ischemia/reperfusion injury in cardiac myocytes. The aim of the present study was to test our lead compounds for cardioprotection in vivo in a rat model of acute myocardial infarction (AMI) in the presence or absence of hypercholesterolemia, one of the major comorbidities affecting cardioprotection.
Normocholesterolemic adult male rats were subjected to 30 min of coronary occlusion followed by 120 min of reperfusion to induce AMI. MMP inhibitors (MMPI)-1154 and -1260 at 0.3, 1, and 3 µmol/kg, MMPI-1248 at 1, 3, and 10 µmol/kg were administered at the 25th min of ischemia intravenously. In separate groups, hypercholesterolemia was induced by a 12-week diet (2% cholesterol, 0.25% cholic acid), then the rats were subjected to the same AMI protocol and single doses of the MMPIs that showed the most efficacy in normocholesterolemic animals were tested in the hypercholesterolemic animals. Infarct size/area at risk was assessed at the end of reperfusion in all groups by standard Evans blue and 2,3,5-triphenyltetrazolium chloride (TTC) staining, and myocardial microvascular obstruction (MVO) was determined by thioflavine-S staining.
MMPI-1154 at 1 µmol/kg, MMPI-1260 at 3 µmol/kg and ischemic preconditioning (IPC) as the positive control reduced infarct size significantly; however, this effect was not seen in hypercholesterolemic animals. MVO in hypercholesterolemic animals decreased by IPC only.
This is the first demonstration that MMPI-1154 and MMPI-1260 showed a dose-dependent infarct size reduction in an in vivo rat AMI model; however, single doses that showed the most efficacy in normocholesterolemic animals were abolished by hypercholesterolemia. The further development of these promising cardioprotective MMPIs should be continued with different dose ranges in the study of hypercholesterolemia and other comorbidities.
我们最近开发了新型基质金属蛋白酶-2（MMP-2）抑制剂小分子，用于对抗缺血/再灌注损伤的心脏保护，并在心肌细胞的缺血/再灌注损伤模型中验证了它们的疗效。本研究的目的是在存在或不存在高胆固醇血症的情况下，在急性心肌梗死（AMI）大鼠模型中测试我们的先导化合物的心脏保护作用，高胆固醇血症是影响心脏保护作用的主要合并症之一。
成年雄性正常胆固醇大鼠接受 30 分钟的冠状动脉闭塞，然后再灌注 120 分钟，以诱导 AMI。MMP 抑制剂（MMPI）-1154 和 -1260 在缺血的第 25 分钟以 0.3、1 和 3µmol/kg 的剂量静脉注射，MMPI-1248 在 1、3 和 10µmol/kg 的剂量下在缺血的第 25 分钟静脉注射。在单独的组中，通过 12 周的饮食（2%胆固醇，0.25%胆酸）诱导高胆固醇血症，然后对这些大鼠进行相同的 AMI 方案，并在高胆固醇血症大鼠中测试在正常胆固醇大鼠中最有效的 MMPIs 的单次剂量。在所有组中，通过标准 Evans 蓝和 2,3,5-三苯基氯化四唑（TTC）染色在再灌注结束时评估梗死面积/危险区，并通过硫代黄素-S 染色确定心肌微血管阻塞（MVO）。
1µmol/kg 的 MMPI-1154、3µmol/kg 的 MMPI-1260 和缺血预处理（IPC）作为阳性对照显著减少了梗死面积；然而，在高胆固醇血症大鼠中未观察到这种作用。IPC 仅降低高胆固醇血症大鼠的 MVO。
这是首次证明 MMPI-1154 和 MMPI-1260 在体内大鼠 AMI 模型中显示出剂量依赖性的梗死面积减少；然而，在正常胆固醇血症大鼠中最有效的单剂量被高胆固醇血症所消除。应继续在高胆固醇血症和其他合并症的研究中用不同的剂量范围进一步开发这些有前途的心脏保护 MMPIs。
