NMR-based metabolomics and breath studies show lipid and protein catabolism during low dose chronic T1 AM treatment.
Related Articles NMR-based metabolomics and breath studies show lipid and protein catabolism during low dose chronic T1 AM treatment.
Obesity (Silver Spring). 2013 Mar 20;
Authors: Haviland JA, Reiland H, Butz DE, Tonelli M, Porter WP, Zucchi R, Scanlan TS, Chiellini G, Assadi-Porter FM
Abstract
OBJECTIVE: 3-iodothyronamine (T1 AM), an analog of thyroid hormone,is a recently discovered fast-acting endogenous metabolite. High single dose treatments of T1 AM have produced rapid short-term effects, including a reduction of body temperature, bradycardia, and hyperglycemia in mice. DESIGN AND METHODS: The present study monitored the effect of daily low doses of T1 AM (10mg/Kg) for eight-days on weight loss and metabolism in spontaneously overweight mice. The experiments were repeated twice (n=4). Nuclear magnetic resonance (NMR) spectroscopy of plasma and real-time analysis of exhaled (13) CO2 in breath by cavity ringdown spectroscopy (CRDS) were used to detect T1 M-induced lipolysis. RESULTS: CRDS detected increased lipolysis in breathshortly after T1 AM administration that was associated with a significant weight loss but independent of food consumption. NMR spectroscopy revealed alterations in key metabolites in serum: valine, glycine, and 3-hydroxybutyrate, suggesting that the subchronic effects of T1 AM include both lipolysis and protein breakdown. After discontinuation of T1 AM treatment, mice regained only 1.8% of the lost weight in the following two weeks, indicating lasting effects of T1 AM on weight maintenance. CONCLUSIONS: CRDS in combination with NMR and (13) C-metabolic tracing constitute a powerful method of investigation in obesity studies for identifying in vivo biochemical pathway shifts and unanticipated debilitating side effects.
PMID: 23512955 [PubMed - as supplied by publisher]
More...