Research published ahead of print in the journal Function suggests that cytokine (proteins secreted by different types of cells) signaling protects pancreatic beta cells from environmental stresses. Beta cell function is impaired in people with diabetes, and scientists have previously thought that exposure to inflammatory cytokines play a role in this type of damage.

Researchers examined and performed single-cell RNA sequencing on pancreatic islets—groups of cells in the pancreas—from mice that were exposed to cytokines for 18 hours. They found cytokine exposure led to expression of genes associated with nitric oxide, a substance that promotes vessel dilation, and “nitric oxide may be an internal ‘off switch’ to prevent the negative effects of prolonged cytokine signaling in islet endocrine cells,” the researchers explained.

“Our findings suggest that the primary functions of cytokines and nitric oxide are to protect islet endocrine cells from damage, and only when regulation of cytokine signaling is lost does irreversible damage occur,” the research team wrote.