title: Dynamic adaptive changes of the serum carnitine esters during and after L-carnitine supplementation in patients with maintenance haemodialysis.
abstract: BACKGROUND
  Here we report the serum carnitine ester profile during and after 1g iv/day L-carnitine supplementation in haemodialysis patients.
  
  
  METHODS
  Seven patients were studied over 29 weeks. After a control day, 12 weeks of replacement therapy was introduced followed by 17 weeks of washout period. The serum acylcarnitine concentrations were determined by isotope dilution ESI MS/MS technique.
  
  
  RESULTS
  At baseline significantly decreased free carnitine (48%, p < 0.01) and a 1.5-16-fold elevation of 16 out of 27 acylcarnitines were detected in HD patients compared with the controls. On the last day of L-carnitine supplementation a 1.6-4.8-fold increase was observed in the acylcarnitine levels compared with day 0; the increase-profile was achieved in four different patterns. The increase rate was rapid and early saturable for C5, C5OH, C6DC, C8:1, C10DC and C18:2 esters, slower for C2, C4, C6, C18 and C18:1 esters, it was slowest and reached a late plateau for C3, C8DC, C14:2, C16 and C16:1, and finally almost gradual increase was seen for 11 acylcarnitines. Three months after the cessation of carnitine treatment marked concentration drops were found for almost all acylcarnitines (by 11-74 % of week 12, p < 0.05); the values further decreased over the five remaining weeks of the observation period.
  
  
  CONCLUSIONS
  Carnitine administration affected the levels of circulating esters in different dynamics and kinetics suggesting a regulated, non-random adaptive reallocation of nutrients. A considerable washout was achieved 3 months after discontinuation of the supplementation; however, the profile still was suggestive for presence of rest of accumulated supplement.
authors.affiliation: Department of Medical Genetics, University of Pécs, Clinical Center, Pécs, Hungary. judit.bene@aok.pte.hu
authors.forename: Judit
authors.initials: J
authors.lastname: Bene
authors.forename: Botond
authors.initials: B
authors.lastname: Csiky
authors.forename: Katalin
authors.initials: K
authors.lastname: Komlosi
authors.forename: Endre
authors.initials: E
authors.lastname: Sulyok
authors.forename: Bela
authors.initials: B
authors.lastname: Melegh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002331:Carnitine / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D016022:Case-Control Studies; D019587:Dietary Supplements; D005260:Female; D005921:Glomerulonephritis / Q000378:metabolism / Q000628:therapy*; D006801:Humans; D008875:Middle Aged; D009397:Nephrocalcinosis / Q000378:metabolism / Q000628:therapy*; D011446:Prospective Studies; D011704:Pyelonephritis / Q000378:metabolism / Q000628:therapy*; D006435:Renal Dialysis; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D002331:Carnitine