Impact of hemodialysis on endogenous plasma and muscle carnitine levels in patients with end-stage renal disease.
BACKGROUND
End-stage renal disease (ESRD) patients undergoing hemodialysis treatment have reduced plasma L-carnitine levels; however, the relationship between dialysis age and carnitine status is poorly understood. This study examined the relationship between duration of dialysis and plasma and skeletal muscle concentrations of L-carnitine and its esters in ESRD patients.


METHODS
Blood samples were collected from 21 patients at baseline and throughout the first 12 months of hemodialysis. In 5 patients, muscle samples were obtained after 0, 6, and 12 months of hemodialysis. Blood and muscle samples were collected from an additional 20 patients with a mean dialysis age of 5.10 years. L-carnitine, acetyl-L-carnitine, and total L-carnitine were measured by high-performance liquid chromatography (HPLC).


RESULTS
The mean +/- SD plasma L-carnitine concentration in ESRD patients who had not yet started hemodialysis was 50.6 +/- 20.0 micromol/L. Significantly lower concentrations were observed after 12 months (29.7 +/- 10.5 micromol/L) and >12 months (22.0 +/- 5.4 micromol/L) of hemodialysis treatment. Acetyl-L-carnitine also declined with dialysis age, while plasma nonacetylated acylcarnitines continued to increase with the progression of hemodialysis therapy. An inverse relationship between dialysis age and muscle L-carnitine concentrations was observed.


CONCLUSIONS
Long-term hemodialysis treatment is associated with a significant reduction in endogenous plasma and muscle L-carnitine levels and a significant increase in plasma acylcarnitines. The majority of the change in plasma L-carnitine concentrations occurs within the first few months of hemodialysis, while muscle levels continue to decline after 12 months of treatment.
Centre for Pharmaceutical Research, School of Pharmaceutical, Molecular and Biomedical Sciences, University of South Australia, Adelaide, South Australia, Australia. allan.evans@unisa.edu.au
Allan M
AM
Evans
Randall J
RJ
Faull
Roger L
RL
Nation
Shilpanjali
S
Prasad
Tony
T
Elias
Stephanie E
SE
Reuter
Gianfranco
G
Fornasini
D000108:Acetylcarnitine / Q000097:blood; D000293:Adolescent; D000328:Adult; D000368:Aged; D002331:Carnitine / Q000097:blood*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism*; D006435:Renal Dialysis
D000108:Acetylcarnitine; D002331:Carnitine