Molecular imaging of matrix metalloproteinases (MMPs) may allow detection of atherosclerotic lesions vulnerable to rupture. In this study, we develop a novel radiolabelled compound that can target gelatinase MMP subtypes (MMP2/9) with high selectivity and inhibitory potency. Inhibitory potencies of several halogenated analogues of MMP subtype-selective inhibitors (N-benzenesulfonyliminodiacetyl monohydroxamates and N-halophenoxy-benzenesulfonyl iminodiacetyl monohydroxamates) were in the nanomolar range for MMP2/9. The analogue with highest inhibitory potency and selectivity was radiolabelled with [123I], resulting in moderate radiochemical yield, and high radiochemical purity. Biodistribution studies in mice, revealed stabilization in blood 1 hour after intravenous bolus injection. Intravenous infusion of the radioligand and subsequent autoradiography of excised aortas showed tracer uptake in atheroprone mice. Distribution of the radioligand showed co-localization with MMP2/9 immunohistochemical staining. In conclusion, we have developed a novel selective radiolabeled MMP2/9 inhibitor, suitable for single photon emission computed tomography (SPECT) imaging that effectively targets atherosclerotic lesions in mice.
分子影像技术对于基质
金属
蛋白酶(
MMPs)的成像可能有助于检测易破裂的动脉粥样硬化病变。在本研究中,我们开发了一种新型放射性标记化合物,该化合物能够高度选择性地靶向明胶酶
MMP亚型(
MMP2/9)并具有抑制活性。几种卤素化类似物的抑制活性对于
MMP亚型选择性
抑制剂(N-
苯磺
酰亚胺二
乙酸单羟
肟酸和N-卤代
苯氧基
苯磺
酰亚胺二
乙酸单羟
肟酸)在纳米摩尔范围内对
MMP2/9有效。具有最高抑制活性和选择性的类似物被[123I]标记,产生了中等放射
化学产率和高度放射
化学纯度。在小鼠中的
生物分布研究表明,静脉注射后1小时血液中稳定。静脉注射放射
配体并随后对切除的主动脉进行自显影显示,易患动脉粥样硬化的小鼠有示踪剂摄取。放射
配体的分布显示出与
MMP2/9免疫组织
化学染色的共定位。总之,我们开发了一种新型选择性放射性标记的
MMP2/9
抑制剂,适用于单光子发射计算机断层摄影术(
SPECT)成像,能有效靶向小鼠的动脉粥样硬化病变。