Modulation of large dense core vesicle insulin content mediates rhythmic hormone release from pancreatic beta cells over the 24h cycle.

ABSTRACT: The rhythmic nature of insulin secretion over the 24h cycle in pancreatic islets has been mostly investigated using transcriptomics studies showing that modulation of insulin secretion over this cycle is achieved via distal stages of insulin secretion. We set out to measure β-cell exocytosis using in depth cell physiology techniques at several time points. In agreement with the activity and feeding pattern of nocturnal rodents, we find that C57/Bl6J islets in culture for 24h exhibit higher insulin secretion during the corresponding dark phase than in the light phase (Zeitgeber Time ZT20 and ZT8, respectively, in vivo). Glucose-induced insulin secretion is increased by 21% despite normal intracellular Ca2+ transients and depolarization-evoked exocytosis, as measured by whole-cell capacitanc

SUBMITTER: Quinault A 

PROVIDER: S-EPMC5854349 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature