title: Cinnamon extract improves insulin sensitivity in the brain and lowers liver fat in mouse models of obesity.
abstract: OBJECTIVE
  Treatment of diabetic subjects with cinnamon demonstrated an improvement in blood glucose concentrations and insulin sensitivity but the underlying mechanisms remained unclear. This work intends to elucidate the impact of cinnamon effects on the brain by using isolated astrocytes, and an obese and diabetic mouse model.
  
  
  METHODS
  Cinnamon components (eugenol, cinnamaldehyde) were added to astrocytes and liver cells to measure insulin signaling and glycogen synthesis. Ob/ob mice were supplemented with extract from cinnamomum zeylanicum for 6 weeks and cortical brain activity, locomotion and energy expenditure were evaluated. Insulin action was determined in brain and liver tissues.
  
  
  RESULTS
  Treatment of primary astrocytes with eugenol promoted glycogen synthesis, whereas the effect of cinnamaldehyde was attenuated. In terms of brain function in vivo, cinnamon extract improved insulin sensitivity and brain activity in ob/ob mice, and the insulin-stimulated locomotor activity was improved. In addition, fasting blood glucose levels and glucose tolerance were greatly improved in ob/ob mice due to cinnamon extracts, while insulin secretion was unaltered. This corresponded with lower triglyceride and increased liver glycogen content and improved insulin action in liver tissues. In vitro, Fao cells exposed to cinnamon exhibited no change in insulin action.
  
  
  CONCLUSIONS
  Together, cinnamon extract improved insulin action in the brain as well as brain activity and locomotion. This specific effect may represent an important central feature of cinnamon in improving insulin action in the brain, and mediates metabolic alterations in the periphery to decrease liver fat and improve glucose homeostasis.
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Member of the German Center for Diabetes Research (DZD), University of Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany.
authors.forename: Tina
authors.initials: T
authors.lastname: Sartorius
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Member of the German Center for Diabetes Research (DZD), University of Tuebingen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Peter
authors.affiliation: German Center for Diabetes Research (DZD), Tuebingen, Germany; Department of Experimental Diabetology, German Institute of Human Nutrition, Potsdam-Rehbruecke, Germany.
authors.forename: Nadja
authors.initials: N
authors.lastname: Schulz
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Member of the German Center for Diabetes Research (DZD), University of Tuebingen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Drescher
authors.affiliation: Department of Nutritional Sciences, SD Model Systems of Molecular Nutrition, Friedrich-Schiller-University Jena, Jena, Germany.
authors.forename: Ina
authors.initials: I
authors.lastname: Bergheim
authors.affiliation: German Center for Diabetes Research (DZD), Tuebingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany; Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tuebingen, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Machann
authors.affiliation: Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tuebingen, Germany.
authors.forename: Fritz
authors.initials: F
authors.lastname: Schick
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Member of the German Center for Diabetes Research (DZD), University of Tuebingen, Germany.
authors.forename: Dorothea
authors.initials: D
authors.lastname: Siegel-Axel
authors.affiliation: German Center for Diabetes Research (DZD), Tuebingen, Germany; Department of Experimental Diabetology, German Institute of Human Nutrition, Potsdam-Rehbruecke, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Schürmann
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Member of the German Center for Diabetes Research (DZD), University of Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany.
authors.forename: Cora
authors.initials: C
authors.lastname: Weigert
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, Member of the German Center for Diabetes Research (DZD), University of Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany.
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Häring
authors.affiliation: German Center for Diabetes Research (DZD), Tuebingen, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany.
authors.forename: Anita M
authors.initials: AM
authors.lastname: Hennige
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D050154:Adiposity / Q000187:drug effects; D000818:Animals; D001253:Astrocytes / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002460:Cell Line; D002935:Cinnamomum zeylanicum / Q000737:chemistry; D002149:Energy Intake; D005054:Eugenol / Q000494:pharmacology* / Q000627:therapeutic use; D006003:Glycogen / Q000096:biosynthesis; D006801:Humans; D007328:Insulin / Q000008:administration & dosage / Q000502:physiology; D007333:Insulin Resistance; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009043:Motor Activity / Q000187:drug effects; D009765:Obesity / Q000188:drug therapy / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D007328:Insulin; D010936:Plant Extracts; D005054:Eugenol; D000171:Acrolein; D006003:Glycogen; C012843:cinnamaldehyde