Dataset for "Promising anti-amyloid behavior of cationic pyridylphenylene dendrimers: role of structural features and mechanism of action"

The study describes the ability of cationic pyridylphenylene dendrimers of the second (G2), third (G3) and fourth (G4) generations to efficiently suppress the amyloid transformation of full-length ovine prion protein. The dendrimers are able to inhibit both the formation of the most toxic soluble oligomers and amyloid fibrils. monitor the secondary structure changes of PrP during oligomerization in the presence of dendrimers, circular dichroism spectroscopy (CD) was performed. CD molar elipticity.opj file collects raw circular dichroism data of the structures obtained when prevented prion protein oligomer formation by the dendrimers. Conversion CD to molar elipticity.xlsx file provides the information about molar elipticity calculation. The data show the formation of beta-sheet structure after incubation of PrP at 65 °C for 150 min without dendrimers, while addition of the dendrimers resulted in the mixed α/β structure.
The formation of protein oligomers was monitored by dynamic light scattering (DLS). Sorokina_oligomers_dls.dts file consists of raw dynamic light scattering data to be opened in Zetasizer Software. The analysis revealed the formation of PrP oligomers of 21 nm in size, while a clear decrease in particle sizes was observed for G3.
An absence of the conversion capacity of PrP-dendrimer complexes obtained when prevented amyloid fibril formation was tested using amyloid seeding assay. For the goal, the complexes resulted in the process of inhibition of amyloid fibril formation by the dendrimers were separated and thoroughly washed from the mixture and added as a seed to the native PrP. Seeding raw data.xslx file summarizes the raw thioflavine T fluorescence data and seeding.opj file represents the statistic calculation. It can be seen that even at low concentrations of 5 and 10 μM dendrimers significantly decrease the fluorescence intensity in comparison with that of the control. The highest impact was observed for G4 that inhibited the process at a concentration of 1 μM. The observations indicate the absence of conversion capacity in the protein-dendrimer complexes as they did not induce the conversion of the native PrP into abnormal form.

本研究阐明了第二代（G2）、第三代（G3）及第四代（G4）阳离子吡啶亚苯树枝状大分子（cationic pyridylphenylene dendrimers）可高效抑制全长羊朊蛋白（ovine prion protein）的淀粉样变性。该类树枝状大分子既能阻断毒性最强的可溶性寡聚体形成，也可抑制淀粉样原纤维的生成。为监测树枝状大分子存在时朊蛋白寡聚化过程中的二级结构变化，本研究采用圆二色光谱法（circular dichroism spectroscopy, CD）开展实验。CD摩尔椭圆率.opj文件存储了树枝状大分子抑制朊蛋白寡聚体形成时所得结构的原始圆二色数据；《CD数据转换为摩尔椭圆率.xlsx》文件则提供了摩尔椭圆率的计算相关信息。实验数据显示，未添加树枝状大分子时，朊蛋白经65℃孵育150分钟后会形成β折叠结构；而添加树枝状大分子后，体系呈现混合的α/β结构。研究通过动态光散射（dynamic light scattering, DLS）监测蛋白质寡聚体的形成。Sorokina_oligomers_dls.dts文件包含原始动态光散射数据，可通过Zetasizer软件打开。分析结果表明，空白对照组中朊蛋白寡聚体粒径为21 nm，而G3处理组的粒子粒径显著降低。为验证经树枝状大分子抑制淀粉样原纤维形成所得的朊蛋白-树枝状大分子复合物是否具备转化活性，本研究采用淀粉样播种实验进行检测。具体步骤为：将树枝状大分子抑制淀粉样原纤维形成过程中得到的复合物分离并充分洗涤后，作为种子添加至天然朊蛋白体系中。《Seeding raw data.xlsx》汇总了硫黄素T（thioflavine T）荧光的原始检测数据，seeding.opj文件则用于统计计算。结果显示，即便在5 μM和10 μM的低浓度下，树枝状大分子仍可显著降低荧光强度；其中G4的抑制效果最佳，在1 μM浓度下即可阻断该过程。上述结果表明，蛋白-树枝状大分子复合物不具备转化活性，无法诱导天然朊蛋白转变为异常构象。