Peroxisomes are small structures inside cells that help remove harmful substances but also break down fats. In animal studies, researchers disrupted these structures and found it damaged the cells that produce insulin (called beta or β cells) in three ways: promoted oxidative stress (a kind of cellular wear and tear), altered the chemical structure of the hormone insulin, and reduced signs that the cells were fully mature and functioning normally. Strangely, the animals released more insulin in response to sugar, yet their bodies were less able to keep blood sugar under control.

The study, published in JCI Insight, helps explain how problems inside cells may drive the loss of healthy insulin production seen in diabetes.

Scientists have developed a new understanding of how fish interact as they school in groups. Fish were found to copy their neighbors to align their movements within schools. The discovery opens a door to examining how the brains of individuals interact to produce group-level collective behavior.