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PubMedDate not supplied

Plasma carotenoids as biomarkers of vegetable intake: the University of Minnesota Cancer Prevention Research Unit Feeding Studies.

High vegetable intake has been associated with a decreased risk for various human cancers in epidemiological studies. Carotenoids are plant compounds that may both possess chemopreventive activity and be useful biomarkers of vegetable and fruit intake. Nineteen men and women were randomized into a controlled cross-over feeding study to measure the effect of vegetable intake on plasma carotenoid concentrations. Participants consumed each of 4 experimental diets for 9 days. The control diet consisted of commonly consumed foods and was essentially carotenoid free. High vegetable diets (carotenoid, cruciferous, and soy) consisted of the control diet plus carrots and spinach (carotenoid), broccoli and cauliflower (cruciferous), and tofu and FriChik (soy). Plasma carotenoid concentrations were highest on the carotenoid and cruciferous diets. When compared to the control, mean plasma alpha-carotene, beta-carotene, and lutein concentrations were 5.2, 3.3 and 2.2 times higher on the carotenoid diet, respectively (P < 0.001). Mean plasma lutein concentrations were 2.1 times higher on the cruciferous versus the control diet (P < 0.001). There were no differences between diets in plasma beta-cryptoxanthin and lycopene concentrations. These data indicate that plasma alpha-carotene, beta-carotene, and lutein may be useful biomarkers of carotenoid-rich food intake and that lutein may act as an intake biomarker of commonly consumed vegetables in the Cruciferae family. These findings should prove useful in undertaking dietary intervention trials because they suggest the feasibility of monitoring intake of some plant foods and of distinguishing among plant food groups.

Adult↗
PubMedDate not supplied

Seasonal variations in plasma micronutrients and antioxidants.

Plasma samples were collected at monthly intervals for a period of 1 year from a group of healthy nonsmoking men and women (n = 21) living in Honolulu, HI. Analysis of plasma cholesterol and triglyceride levels showed marked seasonal variations, with higher mean levels in winter months and lower values in the summer. Cholesterol and triglycerides were highly and inversely correlated with plasma levels of the provitamin A carotenoids. Mean beta- and alpha-carotene levels were highest in late summer and fall. Plasma retinol levels were significantly lower in the summer and higher in the winter. Variations (either between individuals or seasonally) in plasma retinol were unrelated to plasma provitamin A carotenoid levels. Plasma levels of alpha-tocopherol, gamma-tocopherol, beta-cryptoxanthin, and lutein were also higher in the winter and lower in the summer. Significant seasonal correlations, both positive and negative, with environmental variables, such as temperature, solar UV radiation, and rainfall, are noted for many of these plasma micronutrients. The number of samples required to accurately characterize long-term plasma levels for an individual generally ranged from 1 to 4. However, plasma retinol levels exhibited the highest ratio of intra- to interindividual variability, suggesting the need for multiple sampling (> 8 samples) for this micronutrient. Some of this variability for retinol was associated with seasonal changes. Assessment by a diet history of food and supplement intake of micronutrients and phytochemicals for 1 year showed good agreement with 1-year mean plasma levels for most carotenoids, vitamin C, and alpha-tocopherol. Retinol, gamma-tocopherol, cholesterol, and triglyceride levels in plasma were unrelated to estimates of dietary intake.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Serum carotenoids and tocopherols and severity of nuclear and cortical opacities.

PURPOSE: To determine whether higher levels of individual carotenoids and tocopherols in the serum are related to less severe nuclear and cortical opacities within the general population. METHODS: Levels of individual carotenoids and tocopherols in the serum were determined in 400 randomly selected persons aged 50 to 84 years participating in the Nutritional Factors in Eye Disease Study of Beaver Dam, Wisconsin. Severity of nuclear and cortical opacities was assessed from lens slit lamp and retroillumination photographs taken at the same time. Relationships between serum levels of nutrients and prevalence of these opacities were evaluated using logistic regression analysis accounting for known possible confounders. RESULTS: Higher levels of individual or total carotenoids or alpha-tocopherol in the serum were not associated with less severe nuclear or cortical opacities overall. However, associations differed between men and women and within specific population subgroups. A significant trend for lower odds for either type of opacity with increasing levels of beta-carotene in the serum was observed in men. For nuclear sclerosis, this protective association with beta-carotene was found in younger but not older men. Higher levels of three other carotenoids (alpha-carotene, beta-cryptoxanthin, and lutein) in serum were significantly related to lower odds for nuclear sclerosis only in men who smoked. In contrast to these inverse associations observed in some subgroups, higher levels of some carotenoids and alpha-tocopherol often were directly associated with nuclear sclerosis, particularly in women. CONCLUSIONS: Higher levels of carotenoids and tocopherols are not consistently associated with less severe opacities in the general population.

Aged↗
PubMedDate not supplied

Intake of specific carotenoids and lung cancer risk.

Using newly available food composition data for carotenoids, the authors reanalyzed a population-based case-control study of diet and lung cancer conducted in Hawaii in 1983-1985 (L. Le Marchand et al., J. Natl. Cancer Inst., 81: 1158-1164, 1989). The analysis included interviews with 230 men and 102 women with lung cancer and 597 men and 268 women as controls, frequency-matched to the patients by age and sex. A previously validated quantitative diet history assessed the usual intake of foods rich in carotenoids. After adjusting for smoking and other covariates, no association was found with lung cancer risk for dietary lycopene or beta-cryptoxanthin intake, whereas dose-dependent inverse associations of comparable magnitude were found for dietary beta-carotene, alpha-carotene, and lutein. When subjects were cross-classified by their joint intakes of the latter three carotenoids, those who had a high intake (> median) for all three had the lowest risk for lung cancer. In a similar two-way interaction analysis, the previously reported inverse association of lung cancer with vegetable consumption in these data was found to be stronger than that with intake of these three carotenoids. Consistent with our previous findings, this analysis provides further evidence for a protective effect of certain carotenoids against lung cancer and for the greater protection afforded by consuming a variety of vegetables compared to only foods rich in a particular carotenoid.

Carotenoids↗
PubMedDate not supplied

Micronutrient concentrations in paired skin and plasma of patients with actinic keratoses: effect of prolonged retinol supplementation.

Much of our knowledge about the relationship between micronutrients and cancer comes from studies in which plasma (serum) micronutrient levels have been correlated with cancer incidence; however, the relationship between the concentrations of micronutrients in the plasma and in the target tissues has not been established. Ninety-three subjects (62 males and 31 females ages 42-86, median age 69) with actinic keratoses were recruited for investigation of this relationship. The subjects were randomly assigned and received placebo or retinol (25,000 IU/day) intervention for 48 to 65 months as part of a skin cancer chemoprevention trial. Shortly before the end of the trial, three fasting plasma samples and one skin biopsy were obtained from each subject. The concentrations of lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene, cis-beta-carotene, retinol, retinyl palmitate, alpha-tocopherol and gamma-tocopherol in the plasma and skin were simultaneously measured using HPLC. The profiles of the eleven micronutrients in the plasma and skin were similar. Lycopene, beta-carotene and alpha-tocopherol were the predominant micronutrients in both plasma and skin, but the ratio of retinyl palmitate to retinol was much greater in the skin than plasma. The three fasting plasma concentrations from the same subject during a one-month period were very consistent; however, the between-person variations were very large. The retinol supplementation caused a significant increase in the plasma concentrations of retinol, retinyl palmitate, lutein and alpha-tocopherol, especially retinyl palmitate as well as the skin concentrations of retinol and retinyl palmitate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Plasma concentrations of carotenoids and antioxidant vitamins in Scottish males: influences of smoking.

OBJECTIVE: To quantify the major carotenoids in plasma of Scottish males and establish which were affected by habitual smoking. DESIGN: Concentrations of carotenoids, vitamin C and vitamin E (alpha and gamma-tocopherol) were determined in plasma samples from 50 fasted male smokers and 50 age-matched males who had never smoked (aged 50-59 years). RESULTS: Significantly less alpha-carotene, beta-carotene and beta-cryptoxanthin and vitamin C in plasma of smokers than in never-smokers whereas concentrations of lycopene, lutein/zeaxanthin, phytofluene and vitamin E were similar between the groups. CONCLUSION: Whether lower carotenoid and vitamin C concentrations in smokers than never-smokers reflect different dietary patterns or increased metabolic turnover is unclear but smokers may benefit from increased carotenoid and vitamin C intakes.

Ascorbic Acid↗
PubMed1995

[Diet and precancerous gastric lesions: preliminary results of a sampling study of homogeneous population].

The aim of this study was to analyse the relationship between dietary factors and precancerous gastric lesions in the population of a commune in the province of Latina which, on the basis of data published by RTP-LT, appears to present a striking incidence of so-called diet-dependent tumours. A series of tests was used to evaluate the antioxidising (protective) and pro-oxidising (encouraging) capacity of the following substances in terms of cancerogenesis: lutein, zeoxanthine, cryptoxanthine, lycopene, alpha and beta carotene, total carotenoids, tocopherol, retinol, ascorbic acid, cholesterol, HDL cholesterol, triglycerides and ceruloplasmin. Two sample populations were enrolled in the study: sample A (random) composed of 400 persons (202 males and 198 females) aged between 20 and 80 who underwent esophagogastroduodenoscopy and multiple biopsies of the gastric mucous; sample B (random), representative of the population, composed of 400 persons (200 males and 200 females) aged between 20 and 80, who underwent plasmatic assay of lipid and vitamin status. The results of this study appear to confirm the hypothesis of a correlation between diet and pre-cancerous lesions and suggest that the primary preventive stps take the form of: a) reduced intake of animal fat; b) increased consumption of fresh vegetables.

Adult↗
PubMed1996

Changes in the vitamin status of elderly Europeans: plasma vitamins A, E, B-6, B-12, folic acid and carotenoids. SENECA Investigators.

OBJECTIVE: Determination of the plasma vitamin and carotenoid concentrations of a number of elderly populations to describe their micronutrient status and examine geographical patterns and the cross-sectional and longitudinal relationships with sex, age, food and alcohol intake. DESIGN: Longitudinal study. SETTING: Twelve small towns in ten European countries and one in the USA. SUBJECTS: Randomized sample of 1175 subjects of both sexes born in the period 1913-1918, stratified according to age and sex. INTERVENTIONS: Blood plasma collection and determination of alpha-tocopherol, gamma-tocopherol, alpha-carotene, all-trans- and cis-beta-carotene, lycopene, lutein, zeaxanthin, beta-cryptoxanthin, vitamin B-12, folic acid and pyridoxal 5'-phosphate. From the original sample examined in 1988/1989, measurements were repeated in 938 subjects in 1993. RESULTS: There were very large within and between country differences in the micronutrient levels with no definite geographical pattern emerging. The retinol levels decreased significantly between 1988/1989 and 1993 (-0.2 mumol/l, P = 0.0001), unlike the total carotene levels (0.01, NS) while the alpha-tocopherol (0.7 mumol/l, P = 0.002), folic acid (1.1 nmol/l, P < 0.01) and pyridoxal 5'-phosphate (12 nmol/l, P = 0.0001) levels increased significantly. Vitamin B-12 levels increased nonsignificantly in men (17.2 pmol/l, P = 0.77) and decreased significantly in women (-37 pmol/l, P = 0.012). The prevalence of biochemical vitamin A deficiency was zero in both 1988/1989 and 1993, that of vitamin E deficiency decreased from 1.1% to 0.6% and for vitamin B-6 from 23.3% to 5.7%. Vitamin B-12 biochemical deficiency increased from 2.7% to 7.3% and for folic acid from zero to 0.3%. CONCLUSIONS: Changes in the median micronutrient plasma levels over a 4-y period varied, exceeding 30%-40% in some elderly populations. This was reflected in changes, mostly decreases, in the prevalences of vitamin deficiency.

Aged↗
PubMed1996

Lack of correlation between the alpha-tocopherol content of plasma and LDL, but high correlations for gamma-tocopherol and carotenoids.

In 59 healthy human subjects (37 male and 22 female) the concentrations of the lipid-soluble antioxidants alpha- and gamma-tocopherol, alpha- and beta-carotene, lycopene, cryptoxanthin, canthaxanthin, and lutein + zeaxanthin were determined in plasma (mumol/L) and in isolated low density lipoproteins (LDL) (mumol/mmol cholesterol). Plasma alpha-tocopherol concentrations were significantly correlated with plasma total cholesterol concentrations (r2 = 0.51, P < 0.0001) yet not with the LDL alpha-tocopherol content (r2 = 0.05, ns). Plasma gamma-tocopherol concentrations were weakly correlated with plasma total cholesterol (r2 = 0.12, P < 0.003) and both absolute and cholesterol standardized plasma gamma-tocopherol concentrations correlated strongly with the LDL gamma-tocopherol content (r2 = 0.58 and r2 = 0.72, respectively). In contrast, carotenoid concentrations did not correlate with cholesterol concentrations, but their LDL content correlated significantly with the respective plasma concentrations (r2 = 0.67 to 0.92, all P < 0.0001). In a subgroup of study subjects (n = 13) the distribution of vitamin E and carotenoids among LDL was calculated. The proportion of plasma alpha- and gamma-tocopherol found in LDL was 48 +/- 7 (range, 36-61%) and 41 +/- 7%, respectively, suggesting that LDL was in most of these subjects not the main carrier for these antioxidants. The lipophilic carotenoids, however, were predominantly carried by LDL (e.g., beta-carotene: 87 +/- 10%), whereas the proportion of the more polar ones carried by LDL was much smaller (e.g., lutein + zeaxanthin: 36 +/- 6%). The results of this study show that plasma alpha-tocopherol concentrations are not predictive for the alpha-tocopherol content of LDL in nonsupplemented individuals. This finding could have implications in interpreting the cause of the inverse relationship between plasma alpha-tocopherol and risk of atherosclerosis.

Adult↗
PubMed1996

Stability of vitamins A, C, and E, carotenoids, lipids, and testosterone in whole blood stored at 4 degrees C for 6 and 24 hours before separation of serum and plasma.

To investigate whether overnight storage causes significant changes in whole blood, we measured serum and plasma concentrations of vitamins A, C, and E, carotenoids, lipids, and testosterone in whole blood samples stored in a refrigerator at 4 degrees C for 6 and 24 h before centrifugation, aliquoting and freezing them at -70 degrees C or below. In comparison with baseline samples prepared within 2 h, the mean percentage changes at 24 h were: -3.0% to +1.0% for retinol, alpha-tocopherol, and gamma-tocopherol in plasma; -8.7% to -0.1% for carotenoids in plasma; -7.2% for vitamin C in plasma and -1.8% for vitamin C in serum; -2.7% to +2.4% for lipids in serum; and +0.4% to +6.2% for testosterone in serum and plasma from men and women. Spearman's rank correlation coefficients between measurements made in the baseline samples and those made after storage for 24 h were greater than 0.9 for 11 analytes, between 0.8 and 0.9 for 7 analytes, and less than 0.8 for only 1 analyte (vitamin C in serum). The ratio of between-subject to within-subject coefficients of variation was greater than 3.0 for all analytes except lutein (ratio, 1.6), alpha-cryptoxanthin (ratio, 2.4) and vitamin C (ratio in serum, 3.0; ratio in plasma, 2.2). We conclude that storage of whole blood at 4 degrees C for 24 h before freezing does not cause important changes in the analytes studied and that this delay in processing may be incorporated in the design of large prospective studies.

Ascorbic Acid↗
PubMed1996

Fat-soluble vitamins in cord blood and colostrum in the south of China.

Certain diseases have been associated with micronutrient deficiencies in China, and nutritional assessments have become important means of preventing such diseases. In the present study, fat-soluble vitamins including vitamins A, D, E, K, and beta-carotene in the cord blood and colostrum of Chinese subjects in Guilin, China, were assayed and compared with those of Japanese subjects in Osaka, Japan. These vitamins were analyzed by high-performance liquid chromatography. Vitamin A and E levels in the cord blood and colostrum of the Chinese group showed almost the same values as those of the Japanese group. There was also no significant difference in vitamin D level in cord blood between the two groups, while significantly lower levels of beta-carotene and cryptoxanthin, and a higher level of PIVKA-II (protein induced in vitamin K absence) in cord blood were observed in the Chinese group. These findings pointed to a restricted intake of green-yellow vegetables in the Chinese group and an increased risk of hemorrhagic disease in newborn of that group is suggested.

China↗
PubMed1996

Uptake and distribution of carotenoids, retinol, and tocopherols in human colonic epithelial cells in vivo.

Studies suggest that micronutrients such as the tocopherols, retinol, and the carotenoids have a chemopreventive action against colonic carcinogenesis and that they may be essential for the functioning and structural integrity of the gastrointestinal epithelium. In this study, we have determined the concentrations of tocopherols, retinol, and the carotenoids in human colonic epithelial cells using a noninvasive procedure developed in this laboratory (G.P. Albaugh et al., Int. J. Cancer, 52: 347-350, 1992). In subjects on a normal diet, almost all of these micronutrients were restricted to cells in the density range of rho 1.065-1.090 and rho 1.090-1.110. The lighter fraction (rho 1.033-1.064), representing the most senescent subpopulation, retained these micronutrients only when the subjects were on diets rich in vegetables. Cells isolated from subjects on their usual diets gave the following values expressed as ng/10(7) cells: alpha-tocopherol, 93-151; gamma-tocopherol, 152-280; retinol, 12-20; lutein, 4-18; cryptoxanthin, not detected; lycopene, 0-17; alpha-carotene, 3-7; and beta-carotene, 6-9. Peak responses in specific micronutrients following 5 days on a high carotenoid diet showed a lag period of at least 5 days, corresponding to the turnover rates of the epithelium itself. The evidence suggests that uptake of these micronutrients by the colonic mucosa occurs in the deep cryptal zone where the actively proliferating cells extract the nutrients from the systemic circulation.

Carotenoids↗
PubMed1996

Quantitation of vitamin E and a carotenoid pigment in cataractous human lenses, and the effect of a dietary supplement.

The quantitation of tocopherols and carotenoids in lipid extracts of cataractous human lenses was performed in parallel with those of matched samples of plasma, which was also analysed at the same time. Alpha-tocopherol in cataractous lenses from elderly human subjects was present at 4.4 mumoles/kg wet weight, much less than the mean of 33 mumoles/l in plasma from these subjects. The mean ratio of alpha- and gamma-tocopherols was 3.5 in the lenses, and 11.3 in plasma. Lens extracts contained no detectable alpha- or beta-carotene, lycopene, or beta-cryptoxanthin. However, all the lens extracts contained a pigment with the retention time and spectrum of lutein and zeaxanthin. Using the molar extinction coefficient of lutein this was present at ca. 0.03 microM, compared with 0.2 microM in plasma. Seven patients with bilateral cataracts had one of their cataractous lenses removed and analysed, and were then given either an oral placebo, or an oral supplement of ascorbate, alpha-tocopherol and beta-carotene. Three months later, the second cataractous lens, and a blood sample, were analysed. Three of the seven had received the active supplement, as confirmed by substantially raised blood levels of alpha-tocopherol and beta-carotene, and raised aqueous humour levels of vitamin C. However, lens tocopherol levels remained unchanged, and no beta-carotene could be detected in the lenses after supplementation. This preliminary evidence needs to be confirmed in larger studies.

Aged↗
PubMed1998

Concentrations of carotenoids, tocopherols, and retinol in paired plasma and cervical tissue of patients with cervical cancer, precancer, and noncancerous diseases.

Paired blood (collected after an overnight fast) and cervical tissue (cancerous, precancerous, and noncancerous) samples were obtained from 87 patients (age, 21-86 years) who had a hysterectomy or biopsy due to cervical cancer, precancer (cervical intraepithelial neoplasia I, II, and III), or noncancerous diseases. The samples were analyzed using high-performance liquid chromatography for 10 micronutrients (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene, cis-beta-carotene, alpha-tocopherol, gamma-tocopherol, and retinol). The results indicated that: (a) among the three patient groups, the mean plasma concentrations of all micronutrients except gamma-tocopherol were lowest in the cancer patients; however, the mean tissue concentrations of the two tocopherols and certain carotenoids were highest in the cancerous tissue; and (b) among the 10 micronutrients, only the concentrations of beta-carotene and cis-beta-carotene were lower in both the plasma and tissue of cancer and precancer patients than in those of noncancer controls. These results suggest that: (a) not all of the micronutrient concentrations in plasma reflect the micronutrient concentrations in cervical tissue; thus, in some cases, it may be necessary to measure the tissue micronutrient concentrations to define the role of the micronutrients in cervical carcinogenesis; and (b) maintaining an adequate plasma and tissue concentration of beta-carotene may be necessary for the prevention of cervical cancer and precancer.

Adult↗
PubMedDate not supplied

Risk factors for coronary artery disease and levels of lipoprotein(a) and fat-soluble antioxidant vitamins in Asian Indians of USA.

High rates of coronary artery disease have been reported in the Asian Indians who have migrated to other countries. Although many coronary artery disease risk factors (diabetes, high serum cholesterol, lipoprotein[a], and smoking) have been suggested, studies of coronary artery disease risk factors in Asian Indians living in USA are only a few. We investigated coronary artery disease risk factors in 110 Asian Indian physicians living in USA by questionnaire and measurement of their serum lipids and fat-soluble antioxidant vitamins. Differences in risk factors between genders, vegetarian diets and diabetic status were also studied. We found that lipoprotein(a) (mean=20 mg/dl), low density lipoprotein cholesterol, and diabetes (prevalence of 7.5%) are more important risk factors for coronary artery disease, but not smoking, when compared to other Americans. Higher levels of low density lipoprotein cholesterol, retinol, alpha-tocopherol, cryptoxanthin and lycopene, and lower levels of high density lipoprotein cholesterol were found in the males than in females. Comparable levels of lipoprotein(a) were found for males and females. Vegetarians, compared to non-vegetarians, had similar levels of lipids and fat-soluble antioxidants. Lower levels of retinol, lutein/zeaxanthin and lycopene were found in the diabetics compared to non-diabetics. These findings suggest that (1) the control of low density/high density lipoprotein cholesterol levels could be important in prevention of coronary artery disease in Indian males, (2) the vegetarian diets of Asian Indians do not favourably influence the serum lipid and antioxidant levels, and (3) increased serum levels of antioxidants may be beneficial for diabetics. Furthermore, for the first time, we show that serum levels of lutein/zeaxanthin and lycopene are significantly lower in the diabetics.

Adult↗
PubMed1998

The role of carotenoids and retinoids in gap junctional communication.

Induction of gap junctional communication (GJC) is discussed as one possible mechanism underlying the cancer-preventive properties of carotenoids. Structurally different carotenoids have different effects on this GJC pathway. Beta-carotene, echinenone, canthaxanthin, cryptoxanthin and 4-hydroxy-beta-carotene efficiently induce GJC in murine fibroblasts. Decomposition products of canthaxanthin (e.g. 4-oxo-retinoic acid) enhance both GJC and expression of connexin 43 mRNA. Thus, the biological activity of canthaxanthin is due at least in part to formation of active decomposition products such as 4-oxo-retinoic acid. A number of other small molecules such as 1,25-dihydroxycholecalciferol or thyroid hormones serve as nuclear receptor ligands. Cholecalciferol, 3,3',5-triiodo-L-thyronine and L-thyroxine induce GJC to a similar extent as carotenoids or retinoic acid. Interactions between these signalling pathways may be involved in GJC regulation.

Animals↗
PubMed1997

Intracellular carotenoid levels measured by Raman microspectroscopy: comparison of lymphocytes from lung cancer patients and healthy individuals.

Most studies concerning a possible protective role of carotenoids against cancer focus on serum carotenoid levels. We have used Raman microspectroscopy to study the intracellular amounts of carotenoids in lymphocytes of lung cancer patients and of healthy individuals. Our results indicate a significant decrease of carotenoids in lung carcinoma patients compared with healthy individuals, particularly in adenocarcinoma patients. Carotenoid supplementation raised the serum concentration in 2 lung cancer patients up to normal levels, whereas intracellular content remained significantly lower. This indicates that carotenoid uptake by lymphocytes is not only dependent on serum carotenoid concentration. Our findings indicate that Raman microspectroscopy, a recently developed technique to measure intracellular levels of drugs, is also well suited to obtain quantitative data on carotenoid amounts inside cells.

Adenocarcinoma↗
PubMed2004

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. CONCLUSION: 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.

Adult↗