title: Human pancreatic polypeptide has a marked diurnal rhythm that is affected by ageing and is associated with the gastric TFF2 circadian rhythm.
abstract: Normal circadian variations in vasoactive intestinal polypeptide, somatostatin, cholecystokinin and pancreatic polypeptide were measured to determine if these alter with aging and to identify gastrointestinal regulatory hormones that might control the dramatic diurnal variation in the gastric cytoprotective trefoil protein TFF2. Plasma pancreatic polypeptide concentrations showed a marked diurnal rhythm (p < 0.0001). Basal and postprandial pancreatic polypeptide concentrations increased with age (p < 0.01). The timing of the diurnal rhythm was consistent with pancreatic polypeptide inhibiting TFF2 secretion and there was a negative association between pancreatic polypeptide and TFF2 concentrations (p < 0.002). The much higher pancreatic polypeptide concentrations in older people will induce increased satiety that may contribute to 'anorexia of ageing'. These results identify potential therapies for treatment of gastric mucosal morbidity and age-associated loss of appetite.
authors.affiliation: Department of Pathology, University of Newcastle upon Tyne, Royal Victoria Infirmary, Queen Victoria Road, Newcastle upon Tyne NE1 4LP, UK.
authors.forename: C Emma
authors.initials: CE
authors.lastname: Johns
authors.forename: Julia L
authors.initials: JL
authors.lastname: Newton
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Westley
authors.forename: Felicity E B
authors.initials: FE
authors.lastname: May
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging; D002940:Circadian Rhythm; D005247:Feeding Behavior; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D010191:Pancreatic Polypeptide / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000502:physiology*; D013997:Time Factors; D000071164:Trefoil Factor-2
chemical_list: D010455:Peptides; C000604007:TFF2 protein, human; D000071164:Trefoil Factor-2; D010191:Pancreatic Polypeptide