Insulin is secreted by the pancreas in response to elevated blood glucose levels. Insufficient amounts of insulin can result in Type II diabetes, while excess can lead to hypoglycemia — both life-threatening conditions.
Sophie Lewandowski, an IPiB graduate student in the Merrins Lab, studies how pyruvate kinase fits into insulin secretion and regulation.
Pyruvate kinase, an enzyme involved in the last step of glycolysis, has three forms that control metabolic and electrical activity in b-cells and other pancreatic endocrine cells. Lewandowski found that insulin can be secreted by activating pyruvate kinase, which closes ATP-sensitive potassium ion channels.
“This is especially interesting because it disagrees with the consensus model of insulin secretion that says ATP generation from mitochondria [or oxidative phosphorylation] closes ATP-sensitive potassium ion channels,” Lewandowski says.
She also found that pyruvate kinase can amplify insulin secretion. Her research projects, some of which are published in Cell Metabolism, involved several microscopy imaging techniques.
“Throughout my scientific career, I always found it interesting to study how the underlying signaling pathways impact disease,” Lewandowski says. “Between the cool technique and the potential of the work informing future advances in therapeutics, I’ve really enjoyed working on this project.”
She is currently looking for a scientist position in North Carolina.
To learn more about Lewandowski’s research, attend her Ph.D. defense on Friday, December 2 at 9:30 a.m. CT in Room 1211 of the DeLuca Biochemical Sciences Building.