Plasma levels of lipid and cholesterol oxidation products and cytokines in diabetes mellitus and cigarette smoking: effects of vitamin E treatment.
To evaluate the role of both oxidation and inflammation in atherosclerosis, we compared LDL oxidizability, in vivo lipid and cholesterol oxidation, and basal and lipopolysaccharide (LPS)-stimulated production of various cytokines in normolipidemic patients with diabetes mellitus (DM: n = 11), cigarettes smokers (n = 14). In addition, the effects of vitamin E (600 I.U./day for 4 weeks) on these parameters were evaluated. Initial LDL oxidation characteristics before and after vitamin E were identical in the 3 groups. Plasma thiobarbituric acid reactive substances were higher in DM and smokers versus controls (0.77 +/- 0.22, 0.74 +/- 0.14 versus 0.62 +/- 0.10 mumol malondialdehyde equivalents/l, respectively; P versus controls < 0.05) and normalized after vitamin E supplementation. Total plasma oxysterols were higher in smokers versus controls (354 +/- 104 versus 265 +/- 66 nmol/l, P < 0.05) and unaffected by vitamin E. The basal and LPS-stimulated levels of interleukin-1 beta and tumour necrosis factor alpha (TNF alpha) and the basal level of interleukin-1-receptor antagonist (IL-1RA) were identical for the 3 groups. LPS-stimulated IL-1RA was higher in DM versus controls (10.7 +/- 2.0 versus 8.1 +/- 1.7 pmol/l, P < 0.05). After vitamin E, TNF alpha dropped in controls and smokers, and IL-1RA in smokers only. Results suggest increased in vivo oxidative stress and inflammation in DM and smoking, which is partly overcome by vitamin E.
Mol
M J
MJ
Department of Medicine, University Hospital Nijmegen, Netherlands.
de Rijke
Y B
YB
Demacker
P N
PN
Stalenhoef
A F
AF
D000293:Adolescent; D000328:Adult; D000368:Aged; D002784:Cholesterol / Q000097:blood*; D002788:Cholesterol Esters / Q000097:blood; D016207:Cytokines / Q000097:blood*; D003920:Diabetes Mellitus / Q000097:blood*; D005260:Female; D006801:Humans; D007249:Inflammation; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000097:blood; D015227:Lipid Peroxidation; D008055:Lipids / Q000097:blood*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D012795:Sialoglycoproteins / Q000097:blood; D012907:Smoking / Q000097:blood*; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D014810:Vitamin E / Q000494:pharmacology* / Q000627:therapeutic use
D002788:Cholesterol Esters; D016207:Cytokines; C507763:IL1RN protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D008055:Lipids; D008070:Lipopolysaccharides; D012795:Sialoglycoproteins; D017392:Thiobarbituric Acid Reactive Substances; D014409:Tumor Necrosis Factor-alpha; D014810:Vitamin E; D002784:Cholesterol