Oxysterols are increased in plasma of end-stage renal disease patients.
OBJECTIVE
Oxidative stress occurs in chronic renal failure patients undergoing hemodialysis (HD). The objective of our study was to measure oxidation products of cholesterols, so-called oxysterols, in the serum of HD patients in comparison to healthy control persons.


METHODS
In 42 HD patients, plasma oxysterols were measured before and after HD. The values were compared with those in 40 healthy controls. The following cholesterol derivatives were analyzed: dienes, 7beta-OH, beta-epoxy, alpha-epoxy, 20alpha-OH, alpha-triol, and 7-keto cholesterol.


RESULTS
In HD patients, serum levels of oxysterols are increased in comparison to controls. The highest values were measured for beta-epoxy cholesterol and for 20alpha-OH cholesterol. During HD oxysterol concentrations increased, obviously by water removal and concentration of nondialyzable compounds.


CONCLUSIONS
Due to oxidative stress which is known as a typical sign of chronic renal failure the plasma concentrations of oxysterols are also significantly increased in comparison to healthy controls. This underlines the data on accelerated lipid peroxidation in end-stage renal disease (ESRD) patients. Accumulated oxysterols which are accused of exerting atherosclerosis-stimulating effects, which can contribute to the increased cardiovascular risk of ESRD patients, could either induce atherosclerosis via signaling or chronic effects. Direct chemical reactions stimulating plaque formation can be excluded because of the low levels of oxysterols. The share of oxysterols within the total cholesterol ranges from 4 to 15 per thousand.
Research Institute of Physiotherapy and Gerontology, KortexMed Institute of Medical Education, Bad Harzburg, Germany. werner.siems@t-online.de
Werner
W
Siems
Stephan
S
Quast
Daniela
D
Peter
Wolfgang
W
Augustin
Francesco
F
Carluccio
Tilman
T
Grune
Alex
A
Sevanian
Hannelore
H
Hampl
Ingrid
I
Wiswedel
D000368:Aged; D002784:Cholesterol / Q000097:blood*; D002849:Chromatography, Gas; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood*; D015227:Lipid Peroxidation / Q000502:physiology; D008297:Male; D008745:Methylation; D008875:Middle Aged
D002784:Cholesterol