title: Effects of oral meal feeding on whole body protein breakdown and protein synthesis in cachectic pancreatic cancer patients.
abstract: BACKGROUND
  Pancreatic cancer is often accompanied by cachexia, a syndrome of severe weight loss and muscle wasting. A suboptimal response to nutritional support may further aggravate cachexia, yet the influence of nutrition on protein kinetics in cachectic patients is poorly understood.
  
  
  METHODS
  Eight cachectic pancreatic cancer patients and seven control patients received a primed continuous intravenous infusion of l-[ring-(2)H5]phenylalanine and l-[3,3-(2)H2]tyrosine for 8 h and ingested sips of water with l-[1-(13)C]phenylalanine every 30 min. After 4 h, oral feeding was started. Whole body protein breakdown, protein synthesis, and net protein balance were calculated. Results are given as median with interquartile range.
  
  
  RESULTS
  Baseline protein breakdown and protein synthesis were higher in cachectic patients compared with the controls (breakdown: 67.1 (48.1-79.6) vs. 45.8 (42.6-46.3) µmol/kg lean body mass/h, P = 0.049; and synthesis: 63.0 (44.3-75.6) vs. 41.8 (37.6-42.5) µmol/kg lean body mass/h, P = 0.021). During feeding, protein breakdown decreased significantly to 45.5 (26.9-51.1) µmol/kg lean body mass/h (P = 0.012) in the cachexia group and to 33.7 (17.4-37.1) µmol/kg lean body mass/h (P = 0.018) in the control group. Protein synthesis was not affected by feeding in cachectic patients: 58.4 (46.5-76.1) µmol/kg lean body mass/h, but was stimulated in controls: 47.9 (41.8-56.7) µmol/kg lean body mass/h (P = 0.018). Both groups showed a comparable positive net protein balance during feeding: cachexia: 19.7 (13.1-23.7) and control: 16.3 (13.6-25.4) µmol/kg lean body mass/h (P = 0.908).
  
  
  CONCLUSIONS
  Cachectic pancreatic cancer patients have a higher basal protein turnover. Both cachectic patients and controls show a comparable protein anabolism during feeding, albeit through a different pattern of protein kinetics. In cachectic patients, this is primarily related to reduced protein breakdown, whereas in controls, both protein breakdown and protein synthesis alterations are involved.
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands.
authors.forename: David Pj
authors.initials: DP
authors.lastname: van Dijk
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands ; Department of Intensive Care Medicine, Maastricht University Medical Centre Maastricht, The Netherlands.
authors.forename: Marcel Cg
authors.initials: MC
authors.lastname: van de Poll
authors.affiliation: Department of Surgery, Royal Infirmary of Edinburgh Edinburgh, UK.
authors.forename: Alastair Gw
authors.initials: AG
authors.lastname: Moses
authors.affiliation: Stable Isotope Biochemistry Laboratory, Scottish Universities Environmental Research Centre East Kilbride, Glasgow, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Preston
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands.
authors.forename: Steven Wm
authors.initials: SW
authors.lastname: Olde Damink
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands.
authors.forename: Sander S
authors.initials: SS
authors.lastname: Rensen
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands.
authors.forename: Nicolaas Ep
authors.initials: NE
authors.lastname: Deutz
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands.
authors.forename: Peter B
authors.initials: PB
authors.lastname: Soeters
authors.affiliation: Department of Surgery, Royal Infirmary of Edinburgh Edinburgh, UK.
authors.forename: James A
authors.initials: JA
authors.lastname: Ross
authors.affiliation: Department of Surgery, Royal Infirmary of Edinburgh Edinburgh, UK.
authors.forename: Kenneth Ch
authors.initials: KCh
authors.lastname: Fearon
authors.affiliation: Department of Surgery, Maastricht University Medical Centre Maastricht, The Netherlands ; NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Maastricht, The Netherlands ; Department of Surgery, Royal Infirmary of Edinburgh Edinburgh, UK.
authors.forename: Cornelis Hc
authors.initials: CH
authors.lastname: Dejong
keywords: Anabolic resistance; Cancer cachexia; Nutrition; Pancreatic cancer; Protein breakdown; Protein synthesis