title: A single oral dose of flavan-3-ols enhances energy expenditure by sympathetic nerve stimulation in mice.
abstract: Numerous clinical studies have found that ingestion of chocolate reduces the risk of metabolic syndrome, however, the mechanisms were remain unclear. We have reported that a single dose of a flavan-3-ol fraction derived from cocoa (FL) enhanced energy expenditure (EE) and increased the mRNA expression levels of uncoupling proteins (UCPs) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α), and the protein level of phosphorylated AMP-activated protein kinase (AMPK)α in tissues, along with plasma adrenaline level. In the present study, we examined whether the EE enhancing activity of FL is mediated by adrenergic effect using several adrenalin receptor (AR) blockers. In the first study, mice were butoxamine, as β2AR blocker, with vehicle or 10mg/kg FL orally. We found that pretreatment with butoxamine prevented the increases of EE, the mRNA expression of UCP-3, and phosphorylated AMPKα that were induced in the gastrocnemius muscle of mice by 10mg/kg FL. Secondly, mice were given SR52930, as β3AR blocker. Pretreatment with SR52930 prevented the increases of EE, the mRNA expression of UCP-3, and phosphorylated AMPKα that were induced in the gastrocnemius muscle of mice by 10mg/kg FL. Pretreatment with a combination of both blockers also reduced the increments in mRNA expression levels of UCPs and PGC-1α, however, phosphorylated AMPKα in skeletal muscle was rather increased. These results suggest that the ability of a single oral dose of FL to enhance metabolic activity is mediated by sympathetic nerve system (SNS).
authors.affiliation: Department of Bio-science and Engineering, Shibaura Institute of Technology, 307 Fukasaku, Munumaku, Saitama 337-8570, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Kamio
authors.affiliation: Department of Bio-science and Engineering, Shibaura Institute of Technology, 307 Fukasaku, Munumaku, Saitama 337-8570, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Bio-science and Engineering, Shibaura Institute of Technology, 307 Fukasaku, Munumaku, Saitama 337-8570, Japan.
authors.forename: Yuto
authors.initials: Y
authors.lastname: Watanabe
authors.affiliation: Department of Bio-science and Engineering, Shibaura Institute of Technology, 307 Fukasaku, Munumaku, Saitama 337-8570, Japan.
authors.forename: Yoshitomo
authors.initials: Y
authors.lastname: Suhara
authors.affiliation: Department of Bio-science and Engineering, Shibaura Institute of Technology, 307 Fukasaku, Munumaku, Saitama 337-8570, Japan. Electronic address: nao-osa@sic.shibaura-it.ac.jp.
authors.forename: Naomi
authors.initials: N
authors.lastname: Osakabe
mesh_terms: D058672:Adrenergic beta-2 Receptor Antagonists / Q000494:pharmacology; D058673:Adrenergic beta-3 Receptor Antagonists / Q000494:pharmacology; D000818:Animals; D002078:Butoxamine / Q000494:pharmacology; D004734:Energy Metabolism / Q000187:drug effects*; D005419:Flavonoids / Q000008:administration & dosage*; D008297:Male; D008813:Mice, Inbred ICR; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / Q000378:metabolism; D011412:Propanolamines / Q000494:pharmacology; D013564:Sympathetic Nervous System / Q000187:drug effects; D000071256:Uncoupling Protein 1 / Q000378:metabolism
chemical_list: C097869:3-(2-ethylphenoxy)-1-(1,2,3,4-tetrahydronaphth-1-ylamino)-2-propanol oxalate; D058672:Adrenergic beta-2 Receptor Antagonists; D058673:Adrenergic beta-3 Receptor Antagonists; D005419:Flavonoids; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C485290:Ppargc1a protein, mouse; D011412:Propanolamines; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1; D002078:Butoxamine; C404987:flavan-3-ol
keywords: AMPK; Energy expenditure; Flavan-3-ols; Sympathetic nerve system; Uncoupling protein