High-Throughput Luminescent Reporter of Insulin Secretion for Discovering Regulators of Pancreatic Beta-Cell Function

Defects in insulin secretion play a central role in the pathogenesis of type 2 diabetes, yet the mechanisms driving beta-cell dysfunction remain poorly understood, and therapies to preserve glucose-dependent insulin release are inadequate. We report a luminescent insulin secretion assay that enables large-scale investigations of beta-cell function, created by inserting Gaussia luciferase into the C-peptide portion of proinsulin. Beta-cell lines expressing this construct cosecrete luciferase and insulin in close correlation, under both standard conditions or when stressed by cytokines, fatty acids, or ER toxins. We adapted the reporter for high-throughput assays and performed a 1,600-compound pilot screen, which identified several classes of drugs inhibiting secretion, as well as glucose-potentiated secretagogues that were confirmed to have activity in primary human islets. Requiring 40-fold less time and expense than the traditional ELISA, this assay may accelerate the identification of pathways governing insulin secretion and compounds that safely augment beta-cell function in diabetes. [Display omitted] •Proinsulin-Gaussia luciferase fusion construct faithfully reports insulin secretion•Luciferase tracks closely with insulin under normal conditions and induced stress•Reporter enables large-scale study of beta-cell function rapidly and at low cost•1,600-compound screen using assay identifies new human glucose-dependent secretagogues Current assays of beta-cell functions, while useful, have limitations. In this Resource, Burns et al. develop a luminescent reporter of insulin secretion that is 40 times less time-consuming and expensive than ELISA. They perform high-throughput assays of beta-cell function to identify drugs altering human insulin secretion.