The relationships between exogenous and endogenous antioxidants with the lipid profile and oxidative damage in hemodialysis patients.
BACKGROUND
We sought to investigate the relationships among the plasma levels of carotenoids, tocopherols, endogenous antioxidants, oxidative damage and lipid profiles and their possible effects on the cardiovascular risk associated with hemodialysis (HD) patients.


METHODS
The study groups were divided into HD and healthy subjects. Plasma carotenoid, tocopherol and malondialdehyde (MDA) levels, as well as erythrocyte reduced glutathione (GSH), were measured by HPLC. Blood antioxidant enzymes, kidney function biomarkers and the lipid profiles were analyzed by spectrophotometric methods.


RESULTS
Plasma lycopene levels and blood glutathione peroxidase (GPx) activity were significantly decreased in HD patients compared with healthy subjects. Total cholesterol, low-density lipoprotein cholesterol (LDL-c), creatinine, urea, MDA, GSH, superoxide dismutase (SOD) and catalase (CAT) were significantly increased in HD (p < 0.05). Lycopene levels were correlated with MDA (r = -0.50; p < 0.01), LDL-c (r = -0.38; p = 0.01) levels, the LDL-c/HDL-c index (r = -0.33; p = 0.03) and GPx activity (r = 0.30; p = 0.03). Regression models showed that lycopene levels were correlated with LDL-c (β estimated = -31.59; p = 0.04), while gender was correlated with the TC/HDL-c index and triglycerides. Age did not present a correlation with the parameters evaluated. GPx activity was negatively correlated with MDA levels and with the LDL-c/HDL-c and CT/HDL-c indexes.


CONCLUSIONS
Lycopene may represent an additional factor that contributes to reduced lipid peroxidation and atherogenesis in hemodialysis patients.
Laboratory of Toxicology (LATOX), Department of Clinical and Toxicology, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
Miguel
M
Roehrs
Juliana
J
Valentini
Clóvis
C
Paniz
Angela
A
Moro
Mariele
M
Charão
Rachel
R
Bulcão
Fernando
F
Freitas
Natália
N
Brucker
Marta
M
Duarte
Mirna
M
Leal
Geni
G
Burg
Tilman
T
Grune
Solange Cristina
SC
Garcia
D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000453:epidemiology; D002338:Carotenoids / Q000097:blood; D005260:Female; D005978:Glutathione / Q000097:blood; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000378:metabolism* / Q000628:therapy*; D008055:Lipids / Q000097:blood*; D000077276:Lycopene; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D006435:Renal Dialysis; D012307:Risk Factors; D024505:Tocopherols / Q000097:blood
D000975:Antioxidants; D015415:Biomarkers; D008055:Lipids; D002338:Carotenoids; D008315:Malondialdehyde; D005979:Glutathione Peroxidase; D005978:Glutathione; D024505:Tocopherols; D000077276:Lycopene