title: A Pharmacokinetic Model of a Tissue Implantable Cortisol Sensor.
abstract: Cortisol is an important glucocorticoid hormone whose biochemistry influences numerous physiological and pathological processes. Moreover, it is a biomarker of interest for a number of conditions, including posttraumatic stress disorder, Cushing's syndrome, Addison's disease, and others. An implantable biosensor capable of real time monitoring of cortisol concentrations in adipose tissue may revolutionize the diagnosis and treatment of these disorders, as well as provide an invaluable research tool. Toward this end, a mathematical model, informed by the physiological literature, is developed to predict dynamic cortisol concentrations in adipose, muscle, and brain tissues, where a significant number of important processes with cortisol occur. The pharmacokinetic model is applied to both a prototypical, healthy male patient and a previously studied Cushing's disease patient. The model can also be used to inform the design of an implantable sensor by optimizing the sensor dissociation constant, apparent delay time, and magnitude of the sensor output versus system dynamics. Measurements from such a sensor would help to determine systemic cortisol levels, providing much needed insight for proper medical treatment for various cortisol-related conditions.
authors: Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
authors: Michael A
authors: MA
authors: Lee
authors: Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
authors: Naveed
authors: N
authors: Bakh
authors: Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
authors: Gili
authors: G
authors: Bisker
authors: Institute for Medical Engineering and Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
authors: Emery N
authors: EN
authors: Brown
authors: Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA.
authors: Michael S
authors: MS
authors: Strano
mesh_terms: D000224:Addison Disease / Q000378:metabolism; D015374:Biosensing Techniques / Q000379:methods; D001921:Brain / Q000378:metabolism; D003480:Cushing Syndrome / Q000378:metabolism; D005938:Glucocorticoids / Q000378:metabolism; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D008297:Male; D008954:Models, Biological; D008962:Models, Theoretical; D009132:Muscles / Q000378:metabolism
chemical_list: D005938:Glucocorticoids; D006854:Hydrocortisone
keywords: biosensors; cortisol; in vivo; physiologically based pharmacokinetic model