title: Albumin and whole-body protein synthesis respond differently to intraperitoneal and oral amino acids.
abstract: Patients with peritoneal dialysis are at risk for malnutrition and hypoalbuminemia, which are indicators of poor outcome. Recently, it was shown that dialysis solutions containing amino acids (AAs) and glucose improve protein anabolism in peritoneal dialysis patients. We determined if the same solutions could increase the fractional synthesis rate of albumin along with whole-body protein synthesis. Changes in the fractional albumin synthetic rate reflect acute change in hepatic albumin synthesis. A random-order cross-over study compared the effects of Nutrineal (AA source) plus Physioneal (glucose) dialysate with Physioneal alone dialysate. Eight patients in the overnight fasting state were compared to 12 patients in the daytime-fed state. Fractional albumin synthetic rate and whole-body protein synthesis were determined simultaneously using a primed-continuous infusion of L-[1-(13)C]-leucine. Fractional albumin synthesis on AAs plus glucose dialysis did not differ significantly from that on glucose alone in the fasting or the fed state. Protein intake by itself (fed versus fasting) failed to induce a significant increase in the fractional synthetic rate of albumin. Conversely, the oral protein brought about a significant stimulation of whole-body protein synthesis. Our findings show that the supply of AAs has different effects on whole-body protein synthesis and the fractional synthetic rate of albumin.
authors.affiliation: Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands. h.tjiong@erasmusmc.nl
authors.forename: H L
authors.initials: HL
authors.lastname: Tjiong
authors.forename: M W
authors.initials: MW
authors.lastname: Fieren
authors.forename: T
authors.initials: T
authors.lastname: Rietveld
authors.forename: J L
authors.initials: JL
authors.lastname: Wattimena
authors.forename: H
authors.initials: H
authors.lastname: Schierbeek
authors.forename: J G M
authors.initials: JG
authors.lastname: Huijmans
authors.forename: W C
authors.initials: WC
authors.lastname: Hop
authors.forename: G R
authors.initials: GR
authors.lastname: Swart
authors.forename: J W
authors.initials: JW
authors.lastname: van den Berg
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000418:Albumins / Q000096:biosynthesis*; D000596:Amino Acids / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D002097:C-Reactive Protein / Q000378:metabolism; D018592:Cross-Over Studies; D015314:Dialysis Solutions / Q000008:administration & dosage / Q000494:pharmacology*; D005215:Fasting / Q000502:physiology; D005260:Female; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology; D006801:Humans; D007263:Infusions, Parenteral; D008297:Male; D044342:Malnutrition / Q000209:etiology / Q000517:prevention & control; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000009:adverse effects; D014176:Protein Biosynthesis / Q000187:drug effects*; D012709:Serum Albumin / Q000378:metabolism
chemical_list: D000418:Albumins; D000596:Amino Acids; D015314:Dialysis Solutions; D012709:Serum Albumin; D002097:C-Reactive Protein; D005947:Glucose