The Insulin-Like Growth Factors Laboratory of Cheryl A. Conover, Ph.D., pursues research on important cell and tissue growth and survival factors that affect essentially every system and function in the body.

Dr. Conover's research team is expanding knowledge about insulin-like growth factors (IGFs), the receptors that mediate their effects, the IGF binding proteins and proteases that impact IGF action, and the complex interactions among all these components. The information is helping researchers understand the role that the IGF system plays in normal physiology and disease processes.

The IGFs are peptide growth factors, structurally related to insulin, that are important regulators of growth and differentiation in various tissues and cell systems. The actions of the IGFs are, in turn, determined by a family of IGF binding proteins.

Our lab work continues to build on successes that date back to the 1970s, when we discovered a novel enzyme abundant in the plasma of pregnant women that we called pregnancy-associated plasma protein A (PAPP-A). This enzyme enhances IGF activity by degrading inhibitory IGF binding proteins.

Our ongoing studies use methodologies of cell biology, protein biochemistry, immunohistochemistry, molecular biology and microsurgical techniques with genetically engineered mouse models.

We now are finding that beyond pregnancy, PAPP-A also plays a critical role in amplifying local IGF action during fetal development, vascular injury, bone formation and aging. We have generated a line of mice that have the gene for PAPP-A knocked out, which has been and continues to be a valuable model for investigating the physiology and pathophysiology of PAPP-A. In our studies, the knockout mouse model mice lived longer — 30 to 40 percent longer than normal mice — and were resistant to the development or progression of atherosclerosis, diabetic nephropathy, visceral obesity and immune system decline.

Our work may help inform and suggest solutions for age-related diseases in the clinic and could lead to new noninvasive tests for patients at risk of heart attack. PAPP-A may also be a therapeutic target for atherosclerosis, visceral obesity and some cancers.

About Dr. Conover

Dr. Conover has spent her research career investigating the insulin-like growth factor system. Her research has been funded by the National Institutes of Health, the American Heart Association and the Ellison Medical Foundation for Aging Research, among other organizations. In addition to her work in the lab, Dr. Conover is the George M. and Edna B. Endicott Professor of Medicine at the Mayo Clinic College of Medicine and Science in Rochester, Minnesota.