Single Fusion Pore Analysis via Single Cell Amperometry Uncovers Impaired Pore Expansion That Restricts Insulin Exocytosis in Human Type 2 Diabetes.

ABSTRACT: Insulin secretion from vesicles within pancreatic beta cells occurs through the rapid (≤10 ms) process of exocytosis. A crucial final step in this process is the formation of a fusion pore, which connects the insulin vesicle interior to the extracellular space and insulin secretion rate. We employed real-time single-cell amperometry (SCA) with microsensors to quantitatively and dynamically monitor serotonin secretion (used as a proxy for insulin) and alterations in the dynamics of fusion pore formation, including opening, duration, and closing times, during single exocytosis events. Additionally, total internal reflection fluorescence (TIRF) microscopy was used to track docked vesicles and optically measure insulin release. In beta cells from human organ donors with type 2 diabetes (T2D),

SUBMITTER: Hatami A 

PROVIDER: S-EPMC12603977 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature