Keeping it cool: Elucidating the actions of thyronamines in thermoregulation and cardiovascular function

• Applicant: Dr. Carolin Stephanie Höfig, Ph.D.
• Subject Area: Endocrinology, Diabetology, Metabolism
• Term: from 2013 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 240382013

3-Iodothyronamine (3-T1AM) is an endogenous and biologically active cooling substance whose pharmacological actions are opposite to those induced by the classical thermogenic thyroid hormone (TH) T3. Pharmacological doses of 3-T1AM injected into mice lead to profound hypothermia and bradycardia. To date, the mechanisms underlying these effects are still elusive. Given the novel concept that TH can act centrally on thermoregulation and cardiovascular function, we hypothesize that 3-T1AM also affect the central autonomic control of brown fat thermogenesis and heart function. Thus, this project aims to unravel these mechanisms using novel in vivo techniques (e.g. infrared camera, radiotelemetry, blood pressure measurements, stereotaxic injections) to investigate the effect of 3-T1AM and its metabolites in the intact animal. The cellular and tissue localization and characterization of 3-T1AM actions will help to elucidate the underlying molecular mechanisms. In summary, the study will contribute to a better understanding of the counterbalance and physiological homeostasis of thyroid hormone and thyronamine metabolism.

• DFG Programme: Research Fellowships
• International Connection: Sweden
• Participating Persons: Professor Dr. Jens Mittag; Professor Dr. Björn Vennström