The formation of amyloid fibrils causes different degenerative diseases. For example, the polypeptide hormone insulin, comprising 51 amino acids, is directly linked to type II diabetes due to the formation of amyloid-like aggregates. Herein, insulin was used as a model protein to evaluate the solubilizing potential of alpha-cyclodextrin (α-CD) on the sodium dodecylbenzene sulfonate (SDBS) induced amyloid fibril at pH 2.0. Turbidity, Rayleigh light scattering, binding of Thioflavin T dye, and far-ultraviolet circular dichroism analyses were used to characterize the structural conversion induced by α-CD. ThT binding assay showed the formation of amyloid-like aggregates in the insulin in the presence of 0.5 mM of SDBS. The aggregation was solubilized by α-CD in a dose-dependent manner. At low α-CD concentrations (≤5.0 mM), SDBS-induced amyloid fibrils were not inhibited or solubilized. However, amyloid fibrils completely disappeared or solubilized at α-CD >7.0 mM and the native-like secondary structure of insulin was restored. The results clarify the molecular mechanism underlying the effect of α-CD on amyloid fibrillation of insulin induced by SDBS.

淀粉样蛋白原纤维的形成引起不同的退行性疾病。例如，由于形成淀粉样样聚集体，包含51个氨基酸的多肽激素胰岛素直接与II型糖尿病相连。本文中，胰岛素被用作模型蛋白，以评估α-环糊精（α-CD）在pH 2.0的十二烷基苯磺酸钠（SDBS）诱导的淀粉样蛋白原纤维上的增溶潜力。浊度，瑞利光散射，硫黄素T染料的结合以及远紫外圆二色性分析用于表征α-CD诱导的结构转化。ThT结合测定显示在存在0.5 mM SDBS的情况下胰岛素中淀粉样样聚集物的形成。聚集物被α-CD以剂量依赖性方式溶解。在低α-CD浓度（≤5.0mM）下，SDBS诱导的淀粉样蛋白原纤维没有被抑制或溶解。但是，淀粉样蛋白原纤维在α-CD> 7.0 mM时完全消失或溶解，并且恢复了胰岛素的天然样二级结构。该结果阐明了α-CD对SDBS诱导的胰岛素的淀粉样蛋白原纤化作用的潜在分子机制。