Peter Vekilov, associate professor of chemical engineering, and Dimitra Georgiou, a recent doctoral graduate in chemical engineering, both in UH's Cullen College of Engineering, are behind this breakthrough. Since insufficient insulin production in the pancreas is one of the manifestations of adult-onset diabetes, Vekilov and Georgiou are studying the process of how insulin is produced in the first place. Understanding how the body creates this hormone will make it easier for researchers to discover why some individuals do not produce enough insulin and thus develop diabetes, Vekilov said. Specifically, the two have focused on the creation of insulin crystals, the form in which insulin is stored in the pancreas before it is released in the bloodstream.
"It is possible that the insulin deficiency happens when the crystals don't form properly and then part of the insulin that is produced gets destroyed," Vekilov said. Proinsulin, a molecular precursor to insulin itself, is the reason for these crystals. After an insulin molecule is produced from proinsulin, it attaches to an insulin crystal only in special locations where other insulin molecules have formed right angles, called kinks. Using atomic-force microscopy, they discovered a new mechanism by which insulin molecules attach themselves to crystals to form these kinks. They found that groups of insulin blocks create large protrusions, dubbed "mounds" by Vekilov and Georgiou. The very nature of these mounds results in the creation of multiple kinks far more, in fact, than other methods of kink formation.
By providing so many spaces where insulin molecules can attach to an insulin crystal, these mounds allow for the rapid growth of that crystal
Contact: Lisa Merkl
University of Houston