Serum carotenoids and vitamins in relation to markers of endothelial function and inflammation.
BACKGROUND
Endothelial cell dysfunction may be related to an increase in cellular oxidative stress. Carotenoids and vitamins could have an antioxidant-mediated tempering influence on endothelial function and inflammation, thereby reducing the risk of atherosclerosis.


METHODS
We measured serum carotenoids, alpha-tocopherol and Vitamin C concentrations in 379 subjects sampled from the general population. High-sensitive C-reactive protein (CRP), fibrinogen (Fbg) and leukocytes were measured as markers of inflammation. Furthermore, soluble intercellular adhesion molecule-1 (sICAM-1) and flow-mediated vasodilation (FMD; n= 165) were measured as markers of endothelial function. Relationships between serum carotenoids and vitamins and markers of endothelial function and inflammation were analysed after adjustment for confounding.


RESULTS
In the total study group, lutein and lycopene were inversely related to sICAM-1 with regression-coefficients of -0.38+/-0.19 (p = 0.04) and -0.16+/-0.08 (p = 0.04) per 1 micromol/l, respectively. beta-Carotene was inverse related to leukocytes (-0.23+/-0.07; p = 0.007) and CRP (-1.09+/-0.30; p = 0.0003) per 1 micromol/l. Vitamin C was inverse related to CRP (-0.01+/-0.005; p = 0.04) per 1 micromol/l, whereas alpha-tocopherol was positively related to CRP (0.03+/-0.01; p = 0.02) per 1 micro/l. Zeaxanthin was inversely related to FMD (31.2+/-15.3; p = 0.04) per 1 micromol/l.


CONCLUSIONS
The inverse relations between carotenoids, Vitamin C and sICAM-1, CRP and leukocytes may help to explain the possible protective effect of carotenoids and Vitamin C on atherosclerosis through an influence on inflammatory processes and endothelial function.
van Herpen-Broekmans
Wendy M R
WM
TNO Nutrition and Food Research, Zeist, The Netherlands.
Klöpping-Ketelaars
Ineke A A
IA
Bots
Michiel L
ML
Kluft
Cornelis
C
Princen
Hans
H
Hendriks
Henk F J
HF
Tijburg
Lilian B M
LB
van Poppel
Geert
G
Kardinaal
Alwine F M
AF
D000328:Adult; D001205:Ascorbic Acid / Q000097:blood; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis; D002338:Carotenoids / Q000097:blood*; D003430:Cross-Sectional Studies; D065366:Cryptoxanthins; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D005340:Fibrinogen / Q000032:analysis; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood; D000077276:Lycopene; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000097:blood; D014664:Vasodilation / Q000502:physiology; D024341:Xanthophylls; D024502:alpha-Tocopherol / Q000097:blood; D019207:beta Carotene / Q000031:analogs & derivatives* / Q000097:blood
D015415:Biomarkers; D065366:Cryptoxanthins; D024341:Xanthophylls; D019207:beta Carotene; D018799:Intercellular Adhesion Molecule-1; D002338:Carotenoids; D005340:Fibrinogen; D002097:C-Reactive Protein; D024502:alpha-Tocopherol; D001205:Ascorbic Acid; D000077276:Lycopene