Research Briefing Notes

Context of research

Obesity increases the risk of many chronic diseases, including type II diabetes, coronary heart disease, hypertension and some forms of cancer.

What problem is our research addressing?

• Appetite and energy balance involves complex physiological and behavioural mechanisms, orchestrated primarily by the brain, which are overridden by high fat or palatable diets.

• We want to know more about these systems and why they fail to restrain overconsumption of high fat and palatable diets.

Figure 1. Photoperiod exposure drives body weight change in the Siberian hamster.
Imposition of a period of food restriction in short days demonstrates the principle of defendable body weight

Figure 2. Photoperiodic regulation og gene expression in the dmpARC and tanycytes

Figure 3

What are the potential deliverables from this research?

• Identification of brain regions involved in appetite and energy balance.

• Establishing the role of the dmpARC in appetite and energy balance regulation of the Siberian hamster.

• Providing evidence for tanycytes as sensors of metabolic status.

• Identification of new peptides or new mechanisms of action for known peptides and hormones in body weight regulation.

• Commonality of components and mechanisms found in Siberian hamsters to other species

Key References

Barrett,P., Ross,A.W., Balik,A., Littlewood,P.A., Mercer,J.G., Moar,K.M., Sallmen,T., Kaslin,J., Panula,P., Schuhler,S., Ebling,F.J., Ubeaud,C., and Morgan,P.J., Photoperiodic regulation of histamine H3 receptor and VGF messenger ribonucleic acid in the arcuate nucleus of the Siberian hamster, Endocrinology, 146 (2005) 1930-1939.

Ross,A.W., Bell,L.M., Littlewood,P.A., Mercer,J.G., Barrett,P., and Morgan,P.J., Temporal changes in gene expression in the arcuate nucleus precede seasonal responses in adiposity and reproduction, Endocrinology, 146 (2005) 1940-1947.

Ross,A.W., Webster,C.A., Mercer,J.G., Moar,K.M., Ebling,F.J., Schuhler,S., Barrett,P., and Morgan,P.J., Photoperiodic regulation of hypothalamic retinoid signaling: association of retinoid X receptor gamma with body weight, Endocrinology, 145 (2004) 13-20.