insulin tagged posts

rs10830963 is an eQTL in human islets conferring increased MTNR1B mRNA expression • Melatonin inhibits cAMP rises in mouse islets and clonal insulin-secreting cells • Melatonin blocks insulin release in mouse islets and clonal insulin-secreting cells • Melatonin’s inhibition of insulin release is stronger in risk allele carriers

A sleeping pancreas releases less insulin, but how much insulin drops each night may differ from person to person. Up to 30% of the population may be predisposed to have a pancreas that’s more sensitive to the insulin-inhibiting effects of melatonin, a circadian rhythm hormone. People with this increased sensitivity carry a slightly altered melatonin receptor gene that is a known risk factor for type 2 diabetes.

Large-scale studies have identified over 100 ...

Image of a rodent brain cell, with insulin receptors (seen as many green dots) that when activated spur release of dopamine (In background in pink is neuron nucleus.) Credit: Courtesy of Nature Communications

Insulin, essential for controlling blood sugar levels and feeling of being full after eating, plays a much stronger role than previously known in regulating release of dopamine, a neurotransmitter that helps control the brain’s reward and pleasure centers, new studies by researchers at NYU Langone Medical Center show.

“We found that when there’s more insulin in the brain, there will be more dopamine released, not less,” says study senior investigator and NYU Langone neuroscientist Margaret Rice, PhD...