Kovalska V, Chernii S, Losytskyy M, Ostapko J, Tretyakova I, Gorski A, Chernii V, Yarmoluk S
Institute of Molecular Biology and Genetics NASU, Kyiv, Ukraine.
V.I. Vernadskii Institute of General and Inorganic Chemistry NASU, Kyiv, Ukraine.
J Mol Recognit. 2018 Jan;31(1). doi: 10.1002/jmr.2660. Epub 2017 Aug 30.
Formation of the deposits of protein aggregates-amyloid fibrils in an intracellular and intercellular space-is common to a large group of amyloid-associated disorders. Among the approaches to develop of therapy of such disorders is the use of agents preventing protein fibrillization. Polyaromatic complexes-porphyrins and phthalocyanines-are known as compounds possessing anti-fibrillogenic activity. Here, we explore the impact of related macrocyclic complexes-phthalocyanines (Pc) and octaphenyl porphyrazines (Pz) of Mg and Zn-on aggregation of amyloidogenic protein insulin. Pz complexes are firstly reported as compounds able to affect protein fibrillization. The effect of Pc and Pz complexes on the kinetics and intensity of insulin aggregation was studied by the fluorescent assay using amyloid sensitive cyanine dye. This has shown the impact of metal ion on the anti-fibrillogenic properties of macrocyclic complexes-the effect on the fibrillization kinetics of Mg-containing compounds is much more pronounced comparing to that of Zn analogues. Scanning electron microscopy experiments have demonstrated that filamentous fibrils are the main product of aggregation both for free insulin and in the presence of macrocyclic complexes. However, those fibrils are distinct by their length and proneness to lateral aggregation. The Pc complexes cause the increase in variation of fibrils length 0.9 to 2.7 nm in opposite to 1.4 to 2.0 nm for free insulin, whereas Pz complexes cause certain shortening of the fibrils to 0.8 to 1.6 nm. The averaged size of the fibrils population was estimated by dynamic light scattering; it correlates with the size of single fibrils detected by scanning electron microscopy.
蛋白质聚集体——淀粉样原纤维在细胞内和细胞间空间的沉积——是一大类淀粉样变相关疾病的共同特征。开发此类疾病治疗方法的途径之一是使用防止蛋白质纤维化的药物。多芳族配合物——卟啉和酞菁——是已知具有抗纤维化活性的化合物。在此，我们探讨了相关大环配合物——镁和锌的酞菁（Pc）和八苯基卟嗪（Pz）——对淀粉样蛋白胰岛素聚集的影响。Pz配合物首次被报道为能够影响蛋白质纤维化的化合物。通过使用对淀粉样敏感的花青染料的荧光测定法，研究了Pc和Pz配合物对胰岛素聚集动力学和强度的影响。这表明了金属离子对大环配合物抗纤维化特性的影响——与锌类似物相比，含镁化合物对纤维化动力学的影响更为显著。扫描电子显微镜实验表明，丝状原纤维是游离胰岛素和存在大环配合物时聚集的主要产物。然而，这些原纤维在长度和横向聚集倾向方面有所不同。Pc配合物使原纤维长度变化增加到0.9至2.7纳米，而游离胰岛素为1.4至2.0纳米，而Pz配合物使原纤维长度缩短至0.8至1.6纳米。通过动态光散射估计原纤维群体的平均大小；它与扫描电子显微镜检测到的单个原纤维大小相关。
