title: Duodenal lipid sensing activates vagal afferents to regulate non-shivering brown fat thermogenesis in rats.
abstract: Previous evidence indicates that duodenal lipid sensing engages gut-brain neurocircuits to determine food intake and hepatic glucose production, but a potential role for gut-brain communication in the control of energy expenditure remains to be determined. Here, we tested the hypothesis that duodenal lipid sensing activates a gut-brain-brown adipose tissue neuraxis to regulate thermogenesis. We demonstrate that direct administration of lipids into the duodenum increases brown fat temperature. Co-infusion of the local anesthetic tetracaine with duodenal lipids abolished the lipid-induced increase in brown fat temperature. Systemic administration of the CCKA receptor antagonist devazepide blocked the ability of duodenal lipids to increase brown fat thermogenesis. Parenchymal administration of the N-methyl-d-aspartate receptor blocker MK-801 directly into the caudomedial nucleus of the solitary tract also abolished duodenal lipid-induced activation of brown fat thermogenesis. These findings establish that duodenal lipid sensing activates a gut-brain-brown fat axis to determine brown fat temperature, and thereby reveal a previously unappreciated pathway that regulates thermogenesis.
authors.affiliation: Department of Medicine, Diabetes Research Center, Albert Einstein College of Medicine, Bronx, New York, USA.
authors.forename: Clémence
authors.initials: C
authors.lastname: Blouet
authors.forename: Gary J
authors.initials: GJ
authors.lastname: Schwartz
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D001833:Body Temperature Regulation / Q000187:drug effects / Q000502:physiology; D020109:Devazepide / Q000494:pharmacology; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004386:Duodenum / Q000187:drug effects / Q000294:innervation / Q000378:metabolism / Q000502:physiology*; D004435:Eating / Q000187:drug effects / Q000502:physiology; D050356:Lipid Metabolism / Q000502:physiology; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000502:physiology*; D022722:Thermogenesis / Q000187:drug effects / Q000502:physiology*; D014630:Vagus Nerve / Q000187:drug effects / Q000502:physiology*
chemical_list: D016291:Dizocilpine Maleate; D020109:Devazepide