Development of a Liquid Chromatography-Mass Spectrometry-Based Assay for Continuous Hormone Determination

Karim, Enas S., David C. Moore, Braden D. Iveson, and Kendra R. Evans

Endocrine cells secrete and take up several hormones that have been implicated as potential factors in diseases such as type 2 diabetes and obesity.  The hormones include leptin, a protein primarily responsible for regulating appetite, and insulin, which is partially responsible for glucose regulation.  Recent evidence suggests rhythms or cycles exist in the secretion and uptake of endocrine hormones.   These rhythms are of particular interest because biological cycles are believed to have an important role in regulating the drive to eat, and changes in the rhythms may be associated with metabolic diseases.  To enable closer study of these rhythms, it is important to develop reliable, rapid methods of monitoring changes in hormones released by cells. Typically, hormone levels are monitored via radioimmunoassays or enzyme-linked immunosorbent assays; both assays are sensitive but are labor-and time-intensive and costly, and the assays cannot be used to detect simultaneously multiple hormones.  We present progress toward the development of a liquid chromatography-mass spectrometry-based method for automated, simultaneous detection of multiple endocrine hormones.