Professor Julian Mercer - Dietary behaviour and molecular mechanisms
Scottish Government funded work
The cause of obesity in most people is not mutations or polymorphisms in a single gene, but rather the interaction of genetic susceptibility (multiple genes) with environment, where diet is clearly a very influential component, driving over-consumption of calories (energy). Behaviour change (especially in terms of food consumption) is often advocated as essential for long-term resolution of the overweight and obesity issue in the majority of the population. We need strategies for supporting behaviour change that result in beneficial reduction in caloric intake and a shift towards healthier food choices. With Scottish Government funding we will pursue an integrated programme of pre-clinical and human volunteer studies to investigate the psychological, metabolic and physiological characteristics of individuals with specific habitual dietary intakes, and the effect of adopted changes in diet choice on these processes. We will also investigate how dietary choice decisions are made under conditions of caloric restriction i.e. during weight loss attempts, to identify strategies to support these efforts.
EU Funded Projects
NeuroFAST is a project funded by the European Union Seventh Framework Programme. This project examines the Integrated Neurobiology of Food Intake, Addiction and Stress. This multidisciplinary project will explore the neurobiology of addiction and eating behaviour and the complex socio-psychological forces that can lead to its dysregulation. These forces include dietary components (e.g. highly palatable foods and alcohol), some of which may have addictive properties, but also cultural and social pressures and cognitive-affective factors (perceived stress and stress regulation, anxiety and depression), and family-genetic influences on these. The project will provide new data from human studies that is needed to inform health policy initiatives, underpinned by mechanistic research to establish a solid scientific basis for this advice.
Full4Health is a project funded by the European Union Seventh Framework Programme. This project, co-ordinated by the Rowett, will examine the interactions between food and the gut-brain signaling of hunger and satiety (feeling full). Work will encompass pre-clinical models and human volunteer studies where studies will be conducted across a range of age groups, from children to the elderly, with physiological and psychological measures related to and influencing food choice.
The potential to manipulate the mechanisms of hunger and satiety through diet is directly relevant to any policy concerned with obesity, since that condition is largely driven by over-consumption of food. Supporting adequate nutrition in particular clinical circumstances and in the elderly is also a growing concern. The outputs from this project will therefore address vulnerable sectors of the population such as children and the elderly. The results from the project have the potential to enable the development of novel diets, food or supplements, founded on a sound evidence base.
Communications
Julian frequently presents the Rowett research programme to a wide range of audiences including industry and policy stakeholders, and the public in his capacity as Research Theme Leader. He was a speaker at the ‘Science of Eating’ event held at the Scottish Parliament in August 2010 as part of the Festival of Politics and at the British Neuroscience Association Christmas Symposium entitled ‘Food, Glorious Food!’ at the Royal Society, London in December 2011.
Julian is on the steering committee of the British Society for Neuroendocrinology, chairs the Outreach group of the Society, and is leading on the development of a new website for the Society with membership and public engagement content.
Research Grants
NeuroFAST - NeuroFAST(http://www.neurofast.eu/) is a project funded by the European Union Seventh Framework Programme under grant agreement n° 245009. Duration April 2010-March 2015.
Full4Health – Full4Health is a project funded by the European Union Seventh Framework Programme under grant agreement n° 266408. Duration February 2011-January 2016. See http://www.full4health.eu/ for more details.
Policy Briefings
Latest Publications
Helwig, M., Archer, Z.A., Heldmaier, G., Tups, A., Mercer, J.G., Klingenspor, M. Photoperiodic regulation of satiety mediating neuropeptides in the brainstem of the seasonal Siberian hamster (s). Journal of Comparative Physiology A – Neuroethology Sensory Neural and Behavioral Physiology, 195 (7) July 2009 pp. 631-642
Herwig, A., Wilson, D., Logie, T., Boelen, A., Morgan, P.J., Mercer, J.G., Barrett, P. Photoperiod and acute energy deficits interact on components of the thyroid hormone system in hypothalamic tanycytes of the Siberian Hamster. American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, 296 (5) May 2009 pp, R 1037 – R1315
Cottrell, E.C., Cripps, R.L., Duncan, J.S., Barrett, P., Mercer, J.G., Herwig, A., Ozanne, S., Developmental changes in hypothalamic leptin receptor: relationship with the postnatal leptin surge and energy balance neuropeptides in the postnatal rat. American Journal of Physiology, Regulatory, Integrative and Comparative Physiology, 296 (3) pp. R631-R639
Mercer, J.G., Models and mechanisms of energy balance regulation in the young. Proceedings of the Nutrition Society, 67 (4), November 2008 pp. 327-333
Ellis, C., Moar, K.M., Logie, T.J., Ross, A.W., Morgan, P.J., Mercer, J.G. Diurnal profiles of hypothalamic energy balance gene expression with photoperiod manipulation in the Siberian hamster, Phodopus sungorus, American Journal of Physiology – Regulatory, Integrative and Comparative Physiology 294 (4) April 2008. pp. R1148-1153.
K.N. Nilaweera, D. Ozanne, D. Wilson, J.G. Mercer , P.J. Morgan & P. Barrett (2007) G-protein coupled receptor 101 mRNA expression in the mouse brain: altered expression in the posterior hypothalamus and amygdala by energetic challenges. Journal of Neuroendocrinology 19 :34-45.