Surface-Catalyzed Secondary Nucleation Dominates the Generation of Toxic IAPP Aggregates.
Surface-Catalyzed Secondary Nucleation Dominates the Generation of Toxic IAPP Aggregates.
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DOI：
10.3389/fmolb.2021.757425
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发表时间：
2021
影响因子：
5
通讯作者：
Linse S
中科院分区：
文献类型：
--
作者：
Rodriguez Camargo DC;Chia S;Menzies J;Mannini B;Meisl G;Lundqvist M;Pohl C;Bernfur K;Lattanzi V;Habchi J;Cohen SI;Knowles TPJ;Vendruscolo M;Linse S
人胰岛淀粉样多肽（IAPP）的聚集与II型糖尿病相关。在分子水平上对这种联系的定量理解需要IAPP的聚集机制在潜在的微观步骤方面得到解决。在这里，我们系统地研究了重组IAPP，酰胺化的C-末端在氧化形式与残基3和7之间的二硫键，使用硫磺素T荧光监测淀粉样蛋白原纤维的形成作为时间和IAPP浓度的函数。我们使用全局动力学分析连接宏观测量的聚集的微观机制，并表明，新的聚集体的产生是由原纤维表面上的单体的二次成核。然后，我们将胰岛素瘤细胞暴露于从聚集过程的不同时间点提取的等分试样中，发现在反应的中点处毒性最高，此时次级成核速率达到最大值。这些结果确定IAPP低聚物是IAPP聚集期间产生的最具细胞毒性的物质，并表明靶向IAPP次级成核的化合物可能是最有效的II型糖尿病治疗候选药物。
The aggregation of the human islet amyloid polypeptide (IAPP) is associated with diabetes type II. A quantitative understanding of this connection at the molecular level requires that the aggregation mechanism of IAPP is resolved in terms of the underlying microscopic steps. Here we have systematically studied recombinant IAPP, with amidated C-terminus in oxidised form with a disulphide bond between residues 3 and 7, using thioflavin T fluorescence to monitor the formation of amyloid fibrils as a function of time and IAPP concentration. We used global kinetic analyses to connect the macroscopic measurements of aggregation to the microscopic mechanisms, and show that the generation of new aggregates is dominated by the secondary nucleation of monomers on the fibril surface. We then exposed insulinoma cells to aliquots extracted from different time points of the aggregation process, finding the highest toxicity at the midpoint of the reaction, when the secondary nucleation rate reaches its maximum. These results identify IAPP oligomers as the most cytotoxic species generated during IAPP aggregation, and suggest that compounds that target secondary nucleation of IAPP could be most effective as therapeutic candidates for diabetes type II.
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DOI：
10.1136/bmj.i5953
发表时间：
2016-11-23
期刊：
BMJ (Clinical research ed.)
影响因子：
--
作者：
Huang Y;Cai X;Mai W;Li M;Hu Y
通讯作者：
Hu Y
影响因子：
4.1
作者：
HUTTON, JC
通讯作者：
HUTTON, JC
影响因子：
4.1
作者：
DAVIDSON, HW;HUTTON, JC
通讯作者：
HUTTON, JC
影响因子：
5.6
作者：
Kayed, R;Bernhagen, J;Kapurniotu, A
通讯作者：
Kapurniotu, A
DOI：
10.1073/pnas.1218402110
发表时间：
2013-06-11
影响因子：
11.1
作者：
Cohen, Samuel I. A.;Linse, Sara;Knowles, Tuomas P. J.
通讯作者：
Knowles, Tuomas P. J.