title: Neuropeptide Y potentiates beta-adrenergic stimulation of lipolysis in 3T3-L1 adipocytes.
abstract: Recently, we have shown that neuropeptide Y (NPY) is produced and upregulated in visceral adipose tissue of an early-life programmed rat model of central obesity. Moreover, we have demonstrated that NPY promotes proliferation of adipocyte precursor cells and contributes to the pathogenesis of obesity. However, the role of NPY in regulating adipocyte metabolism is poorly understood. The present study was designed to examine the effects of NPY on adipocyte metabolic function using 3T3-L1 adipocytes as an in vitro cell model system. We found that although it did not affect basal lipolysis, NPY potentiated isoproterenol (a β-adrenergic receptor agonist) stimulated lipolysis. Furthermore, this potentiation occurred upstream of adenylyl cyclase, since NPY did not enhance forskolin (an activator of adenylyl cyclase) stimulated lipolysis. In addition, NPY also augmented isoproterenol-stimulated phosphorylation of hormone sensitive lipase. In contrast, NPY did not alter the expression of several key lipolytic and lipogenic enzymes/proteins. Taken together, our results revealed a novel cross talk between the NPY and β-adrenergic signaling pathways in regulating lipolysis. Thus, the present findings add a new dimension to the dynamic role NPY plays in regulating energy balance.
authors: Department of Obstetrics and Gynaecology, The University of Western Ontario, Children's Health Research Institute, Lawson Health Research Institute, London, Ontario, Canada.
authors: Raymond
authors: R
authors: Li
authors: Haiyan
authors: H
authors: Guan
authors: Kaiping
authors: K
authors: Yang
mesh_terms: D041721:3T3-L1 Cells; D000262:Adenylyl Cyclases / Q000378:metabolism; D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism*; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D004734:Energy Metabolism; D020536:Enzyme Activators / Q000494:pharmacology; D064429:Fatty Acid Synthases / Q000378:metabolism; D015870:Gene Expression; D005990:Glycerol / Q000378:metabolism; D007545:Isoproterenol / Q000494:pharmacology*; D008049:Lipase / Q000378:metabolism; D008066:Lipolysis; D051379:Mice; D009478:Neuropeptide Y / Q000502:physiology*; D000070778:Perilipin-1; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D015290:Second Messenger Systems; D013230:Stearoyl-CoA Desaturase / Q000378:metabolism; D002787:Sterol Esterase / Q000378:metabolism; D000217:Acyltransferases
chemical_list: D000262:Adenylyl Cyclases; D000318:Adrenergic beta-Agonists; D002352:Carrier Proteins; D005576:Colforsin; D020536:Enzyme Activators; D064429:Fatty Acid Synthases; D005990:Glycerol; D007545:Isoproterenol; D008049:Lipase; D009478:Neuropeptide Y; D000070778:Perilipin-1; D010750:Phosphoproteins; D013230:Stearoyl-CoA Desaturase; D002787:Sterol Esterase; C490333:Scd1 protein, mouse; C494445:PNPLA2 protein, mouse; D000217:Acyltransferases