title: Passiflora edulis peel intake improves insulin sensitivity, increasing incretins and hypothalamic satietogenic neuropeptide in rats on a high-fat diet.
abstract: OBJECTIVE
  This study aimed to investigate the effect of Passiflora edulis peel flour (PEPF) intake on hypothalamic neuropeptides messenger RNA expression, insulin sensitivity, and other metabolic parameters in Sprague-Dawley rats fed a high-fat (HF) diet.
  
  
  METHODS
  Sprague-Dawley rats were divided in 3 groups: a control group, fed on a normal fat diet; a HF group, fed on a high-fat diet (35% fat [w/w]); and a high-fat Passiflora flour (HFPF) group, fed on a HF diet containing PEPF. The rats from the HFPF group as well as the HF group were kept on an HF diet for the first 4 wk to induce metabolic conditions related to obesity. Then the HFPF group was switched to a HF diet containing PEPF for additional 6 wk. Other groups were kept on normal-fat and HF diet without addition of PEPF during the whole period of experiment. The glucose tolerance and insulin sensitivity were evaluated through the glucose tolerance test (GTT) and the insulin tolerance test (ITT). Gut hormones and adipokines were measured through an immunoassay. The hypothalamic neuropeptides expression was assessed by real-time polymerase chain reaction.
  
  
  RESULTS
  The PEPF intake increased the hypothalamic cocaine- and amphetamine-regulated transcript expression (CART) (P < 0.05), counteracted cumulative body weight gain (P < 0.001), decreased adiposity (P < 0.05) and leptin level (P < 0.01), whereas increased adiponectin (P < 0.01), glucose-dependent insulinotropic polypeptide (P < 0.01), and glucagon-like peptide-1 (GLP-1) (P < 0.001) improved the insulin sensitivity in diet-induced obesity rats by increasing the kITT (glucose disappearance rate) (P < 0.01), which was calculated during the ITT. Other gut hormones (peptide tyrosine tyrosine, pancreatic polypeptide, and amylin) and interleukins (IL) (IL-6, tumor necrosis factor-α, IL-1β, and monocyte chemoattractant protein-1) were not changed by the PEPF intake.
  
  
  CONCLUSIONS
  Our findings provide a further understanding of how the PEPF works as a dietary component to improve glucose homeostasis and demonstrate a molecular mechanism that may increase satiety by PEPF in diet-induced obesity.
authors.affiliation: School of Food Engineering, University of Campinas, São Paulo, Brazil.
authors.forename: Glaucia Carielo
authors.initials: GC
authors.lastname: Lima
authors.affiliation: School of Food Engineering, University of Campinas, São Paulo, Brazil.
authors.forename: Milena Morandi
authors.initials: MM
authors.lastname: Vuolo
authors.affiliation: School of Food Engineering, University of Campinas, São Paulo, Brazil.
authors.forename: Ângela Giovana
authors.initials: ÂG
authors.lastname: Batista
authors.affiliation: Laboratory of Cell Signaling, Faculty of Medical Sciences, University of Campinas, São Paulo, Brazil.
authors.forename: Nathália R V
authors.initials: NR
authors.lastname: Dragano
authors.affiliation: Laboratory of Cell Signaling, Faculty of Medical Sciences, University of Campinas, São Paulo, Brazil.
authors.forename: Carina
authors.initials: C
authors.lastname: Solon
authors.affiliation: School of Food Engineering, University of Campinas, São Paulo, Brazil. Electronic address: mario@fea.unicamp.br.
authors.forename: Mário Roberto
authors.initials: MR
authors.lastname: Maróstica Junior
mesh_terms: D052242:Adiponectin / Q000378:metabolism; D000818:Animals; D059305:Diet, High-Fat; D005749:Gastric Inhibitory Polypeptide / Q000378:metabolism; D052216:Glucagon-Like Peptide 1 / Q000378:metabolism; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D054795:Incretins / Q000378:metabolism*; D007333:Insulin Resistance / Q000502:physiology*; D020738:Leptin / Q000378:metabolism; D008297:Male; D051379:Mice; D023421:Models, Animal; D009479:Neuropeptides / Q000187:drug effects / Q000378:metabolism*; D029598:Passiflora; D016133:Polymerase Chain Reaction; D017207:Rats, Sprague-Dawley
chemical_list: D052242:Adiponectin; D054795:Incretins; D020738:Leptin; D009479:Neuropeptides; D005749:Gastric Inhibitory Polypeptide; D052216:Glucagon-Like Peptide 1
keywords: GLP-1; Insulin resistance; Neuropeptides; Obesity; Passiflora edulis; Pectin