title: Osteoblastic Actions of the Neuropeptide Y System to Regulate Bone and Energy Homeostasis.
abstract: Neural pathways are now a well-appreciated factor in the regulatory milieu controlling the maintenance of bone mass. A number of neural pathways from the brain to bone have been identified. These pathways often involve elements of the energy homeostatic apparatus, indicating links between the regulation of bone metabolism and energy balance. Neuropeptide Y is one such factor that co-regulates these two processes. Initial studies outlined the skeletal actions of NPY from within the brain and the interactions with energy homeostatic processes. However, in recent years, an appreciation for the actions of NPY within bone cells has expanded. Cells of the osteoblastic lineage express both NPY ligand and a cognate receptor NPY, Y1R. Murine studies have demonstrated that both ligand and receptor actively control bone mass and osteoblast activity and interact with mechanical signals to integrate with the local loading environment. Local NPY signalling regulates osteoprogenitor production and differentiation, to cover the entire osteoblastic lineage. In addition, several recent studies have demonstrated extra-skeletal actions of osteoblastic NPY signalling, to regulate energy expenditure and with it adiposity, and in a separate study, to control release of a factor-controlling beta cell mass and insulin production/release and with it glucose tolerance. Thus, osteoblastic neuropeptide production and signalling illustrates the rapidly widening sphere of influence of skeletal tissue, and suggests a far more complex and interconnected physiology then is currently appreciated.
authors.affiliation: Osteoporosis and Bone Biology Division, Garvan Institute of Medical Research, St Vincent's Hospital, 390 Victoria St, Darlinghurst, Sydney, NSW, 2010, Australia.|Department of Biology and Biochemistry, Bath University, Claverton Down Rd, Bath, North East Somerset, BA2 7AY, UK.
authors.forename: Harry
authors.initials: H
authors.lastname: Horsnell
authors.affiliation: Osteoporosis and Bone Biology Division, Garvan Institute of Medical Research, St Vincent's Hospital, 390 Victoria St, Darlinghurst, Sydney, NSW, 2010, Australia. p.baldock@garvan.org.au.|School of Medicine, The University of Notre Dame Australia, 160 Oxford St, Darlinghurst, Sydney, NSW, 2010, Australia. p.baldock@garvan.org.au.|Faculty of Medicine, University of New South Wales, Sydney, NSW, 2052, Australia. p.baldock@garvan.org.au.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Baldock
mesh_terms: D000818:Animals; D015519:Bone Density; D001842:Bone and Bones / Q000378:metabolism*; D049109:Cell Proliferation; D004734:Energy Metabolism; D006706:Homeostasis; D007031:Hypothalamus / Q000378:metabolism; D051379:Mice; D009478:Neuropeptide Y / Q000378:metabolism*; D010006:Osteoblasts / Q000378:metabolism*; D010011:Osteocytes / Q000378:metabolism; D017476:Receptors, Neuropeptide Y / Q000378:metabolism
chemical_list: D009478:Neuropeptide Y; D017476:Receptors, Neuropeptide Y; C097212:neuropeptide Y-Y1 receptor; C095889:neuropeptide Y2 receptor
keywords: Energy balance; Hypothalamus; Mouse model; Neuropeptide Y; Osteoblast