Burke et al..pdf (1.71 MB)
Download file

Sex difference in physical activity, energy expenditure and obesity driven by a subpopulation of hypothalamic POMC neurons.

Download (1.71 MB)
journal contribution
posted on 15.08.2019, 09:33 by LK Burke, B Doslikova, G D'Agostino, M Greenwald-Yarnell, T Georgescu, R Chianese, PB Martinez de Morentin, E Ogunnowo-Bada, C Cansell, L Valencia-Torres, AS Garfield, J Apergis-Schoute, DD Lam, JR Speakman, M Rubinstein, MJ Low, JJ Rochford, MG Myers, ML Evans, LK Heisler
OBJECTIVE: Obesity is one of the primary healthcare challenges of the 21st century. Signals relaying information regarding energy needs are integrated within the brain to influence body weight. Central among these integration nodes are the brain pro-opiomelanocortin (POMC) peptides, perturbations of which disrupt energy balance and promote severe obesity. However, POMC neurons are neurochemically diverse and the crucial source of POMC peptides that regulate energy homeostasis and body weight remains to be fully clarified. METHODS: Given that a 5-hydroxytryptamine 2c receptor (5-HT2CR) agonist is a current obesity medication and 5-HT2CR agonist's effects on appetite are primarily mediated via POMC neurons, we hypothesized that a critical source of POMC regulating food intake and body weight is specifically synthesized in cells containing 5-HT2CRs. To exclusively manipulate Pomc synthesis only within 5-HT2CR containing cells, we generated a novel 5-HT 2C R (CRE) mouse line and intercrossed it with Cre recombinase-dependent and hypothalamic specific reactivatable Pomc (NEO) mice to restrict Pomc synthesis to the subset of hypothalamic cells containing 5-HT2CRs. This provided a means to clarify the specific contribution of a defined subgroup of POMC peptides in energy balance and body weight. RESULTS: Here we transform genetically programed obese and hyperinsulinemic male mice lacking hypothalamic Pomc with increased appetite, reduced physical activity and compromised brown adipose tissue (BAT) into lean, healthy mice via targeted restoration of Pomc function only within 5-HT2CR expressing cells. Remarkably, the same metabolic transformation does not occur in females, who despite corrected feeding behavior and normalized insulin levels remain physically inactive, have lower energy expenditure, compromised BAT and develop obesity. CONCLUSIONS: These data provide support for the functional heterogeneity of hypothalamic POMC neurons, revealing that Pomc expression within 5-HT2CR expressing neurons is sufficient to regulate energy intake and insulin sensitivity in male and female mice. However, an unexpected sex difference in the function of this subset of POMC neurons was identified with regard to energy expenditure. We reveal that a large sex difference in physical activity, energy expenditure and the development of obesity is driven by this subpopulation, which constitutes approximately 40% of all POMC neurons in the hypothalamic arcuate nucleus. This may have broad implications for strategies utilized to combat obesity, which at present largely ignore the sex of the obese individual.

Funding

Work was supported by the Wellcome Trust (WT098012; WT081713) and Biotechnology and Biological Sciences Research Council (BB/K001418/1) to LKH, Wellcome Trust (093566/Z/10/A) to LKB/LKH, the Diabetes UK (13/0004680) to MLE, the Genomics/Transcriptomics core, Disease Model Core, Bespoke Mouse Models, Imaging, Proteomics Wellcome Trust Strategic Award [100574/Z/12/Z] and Genomics/ Transcriptomics Core Facilities, Disease Model Core, CBAL MRC Metabolic Diseases Unit [MRC_MC_UU_12012/5] to LKH, MLE, BD and LKB, the Neuroscience Graduate Program, University of Michigan to MG-Y, the National Institute of Health (DK066604) to MJL and (DK068400) to MJL and MR, and National Institute of Health (DK056731) and the Marilyn H. Vincent Foundation to MGM. The University of Michigan Transgenic Core facility is partially supported by the NIH-funded University of Michigan Center for Gastrointestinal Research (DK034933). The authors would like to thank Dr Samuel Virtue for technical training in BAT lipid accumulation quantification.

History

Citation

Molecular Metabolism, 2016, 5 (3), pp. 245-252

Author affiliation

/Organisation/COLLEGE OF LIFE SCIENCES/Biological Sciences/Neuroscience, Psychology and Behaviour

Version

VoR (Version of Record)

Published in

Molecular Metabolism

Publisher

Elsevier

issn

2212-8778

Acceptance date

14/01/2016

Copyright date

2016

Available date

15/08/2019

Publisher version

https://www.sciencedirect.com/science/article/pii/S221287781600017X

Notes

Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.molmet.2016.01.005.

Language

en