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PubMed1999

A survey of serum and dietary carotenoids in captive wild animals.

Accumulation of carotenoids varies greatly among animal species and is not fully characterized. Circulating carotenoid concentration data in captive wild animals are limited and may be useful for their management. Serum carotenoid concentrations and dietary intakes were surveyed and the extent of accumulation categorized for 76 species of captive wild animals at Brookfield Zoo. Blood samples were obtained opportunistically from 275 individual animals immobilized for a variety of reasons; serum was analyzed for alpha- and beta-carotene, lutein + zeaxanthin, lycopene, beta-cryptoxanthin and canthaxanthin. Total carotenoid content of diets was calculated from tables and chemical analyses of commonly consumed dietary components. Diets were categorized as low, moderate or high in carotenoid content as were total serum carotenoid concentrations. Animals were classified as unknown, high, moderate or low (non-) accumulators of dietary cartenoids. Nonaccumulators had total serum carotenoid concentrations of 0-101 nmol/L, whereas accumulators had concentrations that ranged widely, from 225 to 35,351 nmol/L. Primates were uniquely distinguished by the widest range of type and concentration of carotenoids in their sera. Most were classified as high to moderate accumulators. Felids had high accumulation of beta-carotene regardless of dietary intake, whereas a wide range of exotic birds accumulated only the xanthophylls, lutein + zeaxanthin, canthaxanthin or cryptoxanthin. The exotic ungulates, with the exception of the bovids, had negligible or nondetectable carotenoid serum concentrations despite moderate intakes. Bovids accumulated only beta-carotene despite moderately high lutein + zeaxanthin intakes. Wild captive species demonstrated a wide variety of carotenoid accumulation patterns, which could be exploited to answer remaining questions concerning carotenoid metabolism and function.

Animals↗

PubMed2001

Serum carotenoid depletion follows first-order kinetics in healthy adult women fed naturally low carotenoid diets.

Dietary intakes of carotenoids are highly variable in human populations as are serum carotenoid concentrations. However, there are few controlled data relating carotenoid intake to concentration. Most of the data that are available are from measurements of the absorption and decay of large pharmacologic doses of carotenoids, and are therefore of unknown physiologic relevance. Our objective was to determine the half-life (t(1/2)) of the most abundant carotenoids in blood serum from healthy adult women living under controlled conditions. As part of two carotenoid isotopic studies, we measured serum concentrations of beta-carotene, alpha-carotene, lutein, zeaxanthin, beta-cryptoxanthin and lycopene in 19 healthy young adult women that were fed controlled low carotenoid diets for approximately 10 wk. All other nutrients (vitamins A, E and C) were provided at 100-150% of the 1989 U.S. recommended dietary allowance levels. Exercise and activities were controlled throughout the studies to simulate usual activity patterns. Carotenoid concentrations were measured by reversed-phase HPLC. Serum carotenoid concentration decreases during depletion followed first-order kinetics. The half-lives determined in decreasing order were as follows: lutein (76 d) > alpha-carotene (45 d) = beta-cryptoxanthin (39 d) = zeaxanthin (38 d) = beta-carotene (37 d) > lycopene (26 d). Half-lives were unrelated to physical or demographic characteristics such as body mass, body fat, racial background or age in these relatively homogeneous groups. Carotenoids decreased by similar first-order mechanisms, although the rates differed for individual carotenoids.

Adolescent↗

PubMed2006

Prediagnostic level of serum retinol in relation to reduced risk of hepatocellular carcinoma.

BACKGROUND: Retinol and its derivatives (retinoids), which have antioxidant activity and promote cell differentiation, may protect against the development of hepatocellular carcinoma (HCC) by controlling hepatocellular differentiation and reducing inflammatory responses. METHODS: We examined prospectively the relationship between prediagnostic serum concentrations of retinol, alpha-carotene; beta-carotene; beta-cryptoxanthin; lutein; lycopene; zeaxanthin; alpha-, gamma-, and delta-tocopherols; and selenium and the risk of developing HCC among 213 patients with HCC and 1087 matched control subjects from a cohort of 18,244 men in Shanghai, China, who were monitored from 1986 through 2001. Odds ratios (ORs) and 95% confidence intervals (CIs) for men by quartile of serum concentrations of micronutrients were estimated by using logistic regression with adjustment for cigarette smoking status, alcohol intake, self-reported history of physician-diagnosed hepatitis or liver cirrhosis at recruitment, and seropositivity for hepatitis B surface antigen (HBsAg). All statistical tests were two-sided. RESULTS: Men with high prediagnostic serum retinol levels had a lower risk of HCC than men in the lowest quartile (Q2 versus Q1, OR = 0.37, 95% CI = 0.22 to 0.61; Q3 versus Q1, OR = 0.30, 95% CI = 0.17 to 0.50; and Q4 versus Q1, OR = 0.13, 95% CI = 0.06 to 0.26; Ptrend < .001). A statistically significant interaction was observed between retinol and HBsAg seropositivity on HCC risk; HBsAg-positive men in the lowest tertile of retinol had a greater than 70-fold higher risk (OR = 72.7, 95% CI = 31.6 to 167.4) of HCC than HBsAg-negative men in the highest tertile of retinol (Pinteraction = .018). No independent effect of serum levels of alpha-carotene; beta-carotene; beta-cryptoxanthin; lutein; lycopene; zeaxanthin; alpha-, gamma-, and delta-tocopherols; or selenium on HCC risk were observed. CONCLUSION: High prediagnostic serum level of retinol is associated with a decreased risk of HCC in this population.

Carcinoma, Hepatocellular↗

PubMed1995

Liposoluble vitamins and naturally occurring carotenoids in porphyria cutanea tarda.

The authors consider two groups of patients with overt sporadic porphyria cutanea tarda (PCT) from different continents, with the aim of evaluating the possible impairment of the liposoluble antioxidative system, given the possible synergic effect of porphyrins and iron in promoting oxidative cellular damage. Twenty-three Italian outpatients with overt sporadic PCT and 11 outpatients with PCT from Buenos Aires (Argentina) were matched with 60 patients with liver cirrhosis and 52 healthy Italian controls. Serum levels of alpha- and beta-carotene, cryptoxanthin, zeaxanthin, lutein, lycopene, retinol and alpha-tocopherol were detected by a high-performance liquid chromatographic technique devised in our laboratory, which afforded an accurate and simultaneous resolution of all these compounds. The results point to a significant reduction in plasma levels of alpha- and beta-carotene in both the PCT populations with respect not only to controls, but also to the cirrhotic population, which had more severe liver damage. Moreover, other carotenoids with proven antioxidative properties, like cryptoxanthin and lycopene, are greatly reduced in our PCT populations. This confirms the suggested synergic effect of iron and porphyrins in the oxidative intracellular damage with consequent depletion of antioxidative liposoluble molecules.

Alkaline Phosphatase↗

PubMed2002

Serum and liver micronutrient antioxidants and serum oxidative stress in patients with chronic hepatitis C.

OBJECTIVES: The exact pathogenesis of liver injury and fibrosis in chronic hepatitis C (CHC) is unclear. Free radicals play a role in CHC liver damage. Antioxidants (AO) (enzymatic and nonenzymatic) scavenge free radicals and prevent tissue injury. The aims of our study were to estimate serum levels of malondialdehyde (MDA), serum and liver levels of nonenzymatic fat-soluble AO, and to correlate the liver AO levels with the degree of inflammation and fibrosis on biopsy. METHODS: AO levels were estimated by high-pressure liquid chromatography in the pretreatment serum and liver biopsy specimen of 20 treatment-naïve patients with CHC who were not on vitamin supplements. Serum levels of MDA were measured as a marker of increased oxidative stress. Twenty-two healthy individuals with no history of vitamin supplementation served as controls. AO analyzed were: retinol, alpha- and gamma-tocopherol, lutein, beta-cryptoxanthin, lycopene, and alpha- and beta-carotene. RESULTS: Twenty CHC patients (11 men, nine women, mean age 48.5 +/- 7.9 yr) were studied. Patients and controls were comparable in age and sex. Serum MDA levels were significantly higher in CHC patients compared with controls (1.62 +/- 0.57 vs 0.23 +/- 0.15 micromol/L, p = < 0.0000). Serum levels of all AO except lutein were significantly decreased in CHC patients, and their levels were two to ten times lower than serum levels in controls. Liver levels of alpha-carotene (p = 0.0004), beta-carotene (p = 0.006), and lutein (p = 0.002) correlated with the serum levels, whereas the levels of retinol, alpha-tocopherol, lycopene, and beta-cryptoxanthin showed no correlation. Serum MDA levels were significantly higher in patients with moderate-to-severe inflammation or fibrosis compared with those with mild inflammation or fibrosis. The levels of all liver AO except alpha-carotene were significantly lower in patients with moderate-to-severe fibrosis. The severity of inflammation (portal or lobular) did not affect liver AO levels. CONCLUSIONS: Our findings suggest that increased oxidative stress is present in patients with CHC. Micronutrient AO are severely depleted in serum and liver tissue of patients with CHC, and liver levels of some AO appear to reflect serum levels. Increasing fibrosis is associated with decreased liver AO levels indicating that severe disease may be a consequence of AO depletion or decreased liver storage resulting from fibrosis.

Adult↗

PubMed2004

Serum carotenoid and retinol levels during childhood infections.

BACKGROUND: In recent years, new physiological functions of vitamin A have been identified, including its role in immune defense. The antioxidant potential of carotenoids is thought to account for their health benefits. The aim of this study was to investigate the concentration changes in the provitamin-A (alpha- and-beta-carotene, beta-cryptoxanthin) and of the non-provitamin-A carotenoids (lutein, zeaxanthin and lycopene) in children with acute infections. METHODS: Serum retinol and carotenoid concentrations were measured by HPLC in 45 children suffering from acute infections and in 29 healthy controls. In addition 15 healthy children collected food samples over 2 days. C-reactive protein (CRP) levels were measured by turbidimetry. RESULTS: Serum levels of beta-carotene, alpha-carotene, beta-cryptoxanthin and retinol and non-provitamin-A carotenoid lutein and zeaxanthin concentrations were significantly lower in children with infections compared to healthy controls. There were significant negative correlations between CRP levels and serum beta-carotene and retinol concentrations. The average intake of retinol equivalents was 1.1 +/- 0.6 mg/day. CONCLUSION: Serum retinol and provitamin-A as well as non-provitamin-A carotenoid concentrations were lower in children with acute phase infections compared to healthy controls. The inverse correlations between CRP and beta-carotene or retinol indicate either decreased synthesis or increased utilization of these antioxidants.

Adolescent↗

PubMed1999

Comparison of serum carotenoid responses between women consuming vegetable juice and women consuming raw or cooked vegetables.

The objective of this study was to examine serum concentrations of alpha-carotene, beta-carotene, lutein, lycopene, and beta-cryptoxanthin due to consumption of vegetable juice versus raw or cooked vegetables. Subjects included female breast cancer patients who had undergone surgical resection and who were enrolled in a feasibility study for a trial examining the influence of diet on breast cancer recurrence. A high-vegetable, low-fat diet was the focus of the intervention, and some of the subjects were specifically encouraged to consume vegetable juice. At 12 months, blood samples were collected and analyzed for carotenoid concentrations via high-performance liquid chromatography methodology. Matched analysis and paired t test were conducted on two groups: those who consumed vegetable juice (the juice group) and those who consumed raw or cooked vegetables (no juice group). Serum concentrations of alpha-carotene and lutein were significantly higher in the vegetable juice group than in the raw or cooked vegetable group (P < 0.05 and P = 0.05, respectively). Paired t test analysis did not demonstrate a significant difference in serum values of beta-carotene, lycopene, and beta-cryptoxanthin between subjects consuming juice and those not consuming any juice. These results suggest that alpha-carotene and lutein appear to be more bioavailable in the juice form than in raw or cooked vegetables. Therefore, the food form consumed may contribute to the variability in serum carotenoid response to vegetable and fruit interventions in clinical studies.

Adolescent↗

PubMed2001

Inverse associations between plasma lycopene and other carotenoids and prostate cancer.

Although dietary intake of tomatoes and tomato products containing lycopene has been reported to reduce the risk of prostate cancer, few studies have been done on the relationship between plasma lycopene and other carotenoids and prostate cancer. This case-control study was conducted to investigate the effects of plasma lycopene, other carotenoids, and retinol, as well as alpha- and gamma-tocopherols on the risk of prostate cancer. The study included 65 patients with prostate cancer and 132 cancer-free controls; all of them were interviewed using a standard epidemiological questionnaire at the Memorial Sloan-Kettering Cancer Center from 1993 to 1997. Plasma levels of carotenoids, retinol, and tocopherols were measured by high performance liquid chromatography. An unconditional logistic regression model was used in bivariate and multivariate analyses using Statistical Analysis System (SAS). After adjusting for age, race, years of education, daily caloric intake, pack-years of smoking, alcohol consumption, and family history of prostate cancer, significantly inverse associations with prostate cancer were observed with plasma concentrations of the following carotenoids: lycopene [odds ratio (OR), 0.17; 95% confidence interval (CI), 0.04-0.78; P for trend, 0.0052] and zeaxanthin (OR, 0.22; 95% CI, 0.06-0.83; P for trend, 0.0028) when comparing highest with lowest quartiles. Borderline associations were found for lutein (OR, 0.30; 95% CI, 0.09-1.03; P for trend, 0.0064) and beta-cryptoxanthin (OR, 0.31; 95% CI, 0.08-1.24; P for trend, 0.0666). No obvious associations were found for alpha- and beta-carotenes, retinol, and alpha- and gamma-tocopherols. Our study confirmed the inverse associations between lycopene, other carotenoids such as zeaxanthin, lutein, and beta-cryptoxanthin, and prostate cancer. This study provides justification for further research on the associations between lycopene and other antioxidants and the risk of prostate cancer.

Adult↗

PubMed2003

Toenail selenium levels and the subsequent risk of prostate cancer: a prospective cohort study.

Results of a randomized controlled trial have suggested a protective effect of selenium against prostate cancer. Few other prospective studies have been conducted to confirm or refute this. The association between prostate cancer and baseline toenail selenium level was evaluated in the Netherlands Cohort Study, conducted among 58,279 men, aged 55-69 years at entry. In September 1986, the cohort members completed a questionnaire on risk factors for cancer and provided toenail clippings for determination of baseline selenium status. After 6.3 years of follow-up, 540 incident prostate carcinoma cases and 1,211 subcohort members with complete toenail selenium data were available for case-cohort analyses. In multivariate survival analysis, an inverse association between toenail selenium level and prostate cancer risk was observed. Incidence rate ratios in increasing selenium quintiles were 1.00 (ref), 1.05, 0.69, 0.75, and 0.69 (95% confidence interval, 0.48-0.99), respectively (P-trend=0.008). This association persisted after exclusion of cases diagnosed during early follow-up. The inverse association was more pronounced in ex-smokers than current smokers, and unclear in never-smokers. Analysis of effect modification by intake of antioxidant vitamins C, E, and the carotenoids alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin showed a strong, significant interaction with beta-cryptoxanthin, and to a lesser extent with vitamin C. These results confirm the hypothesis that higher selenium intake may reduce prostate cancer risk. Future research on optimum dose level is needed.

Aged↗

PubMedDate not supplied

Relationship between obesity and serum markers of oxidative stress and inflammation in Japanese.

The present study was conducted to assess the relationship between obesity and serum levels of C-reactive protein (CRP), carotenoids, oxidized LDL (oxLDL), oxidized LDL antibodies (oLAB), and leptin in Japanese residents. The subjects were 158 males and 158 females aged 40-79 years, and living in Hokkaido, Japan, who attended a health examination screening. Serum levels of CRP, oxLDL, oLAB, and leptin were measured by enzyme-linked immunosorbent assay (ELISA) and serum carotenoid levels were measured by high-performance liquid chromatography (HPLC). Body mass index (BMI) was calculated as body weight (kg) divided by height (m) squared and obesity was defined as BMI of 25 or more (kg/m2). Serum levels of CRP and leptin were significantly higher in the obese group than in their non-obese counterparts in both genders. Serum levels of beta-carotene and beta-cryptoxanthin were lower in the obese individuals, especially in females. While values for oxLDL and oLAB did not significantly vary. BMI was positively correlated with log-transformed serum levels of CRP and leptin in both genders (males: r=0.231, p<0.05; females: r=0.305, p<0.001). In females, moreover, BMI was negatively correlated with log-transformed serum levels of beta-carotene, zeaxanthin/lutein, and beta-cryptoxanthin (r=-0.244, p<0.01; r=-0.200, p<0.05; r=-0.207, p<0.01, respectively). Significantly higher odds ratios (ORs) for high serum levels of CRP (males: OR=2.12; females: OR=3.96) and leptin (males: OR=3.83; females: OR=9.07) were observed in obese versus non-obese men and women, after adjusting for various confounding factors. Significantly lower adjusted odds ratios for high serum levels of alpha- and beta-carotenes (males: OR=0.23, 0.33; females: OR=0.35, 0.39, respectively) were also observed in the obese as compared to the non-obese group. In conclusion, obesity is highly associated with states of oxidative stress and low-grade inflammation in Japanese residents, suggesting that these latter might play an important role in the association between a high BMI and certain cancers as well as coronary heart disease (CHD).

Adult↗

PubMed2004

Carotenoid status among preschool children with vitamin A deficiency in the Republic of the Marshall Islands.

Although carotenoids are known to be important dietary sources of vitamin A, there have been few epidemiological studies that have characterized the serum concentrations of major dietary carotenoids among preschool children with vitamin A deficiency. We conducted a population-based, cross-sectional study of serum pro-vitamin A carotenoids (alpha -carotene, beta-carotene, beta-cryptoxanthin), non-provitamin A carotenoids (lutein/zeaxanthin, and lycopene), and retinol among 278 children, aged 1-5 y, in the Republic of the Marshall Islands. Vitamin A deficiency was defined as serum retinol <0.70 micromol/L. Geometric mean serum concentrations of carotenoids among children with and without vitamin A deficiency were 0.003 vs 0.006 micromol/L for alpha-carotene (P = 0.0017), 0.011 vs 0.023 micromol/L for beta-carotene (P <0.0001), 0.023 vs 0.034 micromol/L for beta-cryptoxanthin (P = 0.0075), 0.007 vs 0.012 micromol/L for lycopene (P = 0.037), 0.044 vs 0.052 micromol/L for lutein/zeaxanthin (P = 0.2), and 0.045 vs 0.074 micromol/L for total provitamin A carotenoids (P <0.0001) respectively. In a multivariate analysis adjusting for sex, age (Odds Ratio [O.R.] 1.44, 95% confidence interval [C.I.] 1.16-1.78), and serum provitamin A carotenoids (O.R. 0.49, 95% C.I. 0.34-0.71) were associated with vitamin A deficiency, but serum non-provitamin A carotenoids were not associated with vitamin A deficiency (O.R. 0.93, 95% C.I. 0.67-1.28). Preschool children with vitamin A deficiency in the Republic of the Marshall Islands have extremely low serum concentrations of provitamin A carotenoids and interventions are needed to improve the dietary intake of provitamin A carotenoids among Marshallese children.

Antioxidants↗

PubMed2006

Carotenoid-membrane interactions in liposomes: effect of dipolar, monopolar, and nonpolar carotenoids.

Electron paramagnetic resonance (EPR) spin-labeling methods were used to study the effects of carotenoids on the physical properties of saturated phosphatidylcholine (PC) membranes to evaluate the contribution of the terminal hydroxyl groups of xanthophyll molecules to the carotenoid-membrane interaction. Effects of the dipolar, terminally dihydroxylated carotenoid lutein on membrane phase transition, fluidity, order, and polarity were compared with those of monopolar (beta-cryptoxanthin) and nonpolar (beta-carotene) carotenoids. These effects were monitored at the membrane center as a function of the amount of the carotenoid added to the sample and as a function of temperature for fluid-phase membranes. PC membranes with different thickness (from 12 to 22 carbons in alkyl chains) were used. Carotenoids shifted to lower temperatures and broadened the main phase transition of PC membranes. They decreased the membrane fluidity and increased the order of alkyl chains. Carotenoids also increased the hydrophobicity of the membrane interior. These effects were the strongest for lutein, significantly weaker for beta-cryptoxanthin, and negligible for beta-carotene. They decreased with the increase of the membrane thickness. Presented results suggest that anchoring of carotenoid molecules at the opposite membrane surfaces by polar hydroxyl groups is significant in enhancing their effects on membrane properties. This manuscript also shows the ability of EPR spin-labeling methods to monitor different membrane properties that can be applied in biotechnological studies with the use of liposomes.

Carotenoids↗

PubMed1994

Antioxidant vitamins in malnourished Nigerian children.

The antioxidant capacity in malnutrition--as far as it is related to vitamins--was studied by determining the plasma concentrations of the most prominent antioxidant vitamins (retinol, tocopherols, carotenoids, cryptoxanthine, lycopene, and ubiquinone-10) in marasmic (M; n = 15), severe marasmic (SM; n = 8), kwashiorkor (KW; n = 12), and normally nourished (CO; n = 18) children in Nigeria. Retinol was found to be reduced in severe marasmic children when compared to local controls (medians and interquartile ranges; SM: 155 micrograms/l, 117-178 micrograms/l; CO: 281 micrograms/l 209-413 micrograms/l; p < 0.005). A strong correlation between plasma retinol and retinol binding protein could be found in all groups (SM: r = 0.79; M: r = 0.93; KW: r = 0.80; CO: r = 0.70). The tocopherol/lipid-ratio was lowered in kwashiorkor (median 0.48 mg/g, interquartile range 0.41-0.66 mg/g). A sufficient tocopherol status was only found in one child with kwashiorkor. alpha-Carotene, beta-carotene, cryptoxanthine and lycopene were below the detection limits in most of the malnourished children. Plasma ubiquinone-10 was significantly higher in kwashiorkor (median 1.05 micrograms/ml, interquartile range 0.88-1.17 micrograms/ml) than in all other groups (CO: 0.71 micrograms/ml, 0.55-0.99 micrograms/ml: M: 0.72 micrograms/ml, 0.65-0.83 micrograms/ml; SM: 0.89 micrograms/ml, 0.61-0.83 micrograms/ml). It is concluded that a depletion of antioxidant vitamins is present in malnourished Nigerian children, especially pronounced in the kwashiorkor syndrome. The mechanisms leading to elevated plasma ubiquinone-10 in kwashiorkor require further studies.

Antioxidants↗

PubMed1994

Plasma carotenoids as biomarkers of vegetable and fruit intake.

Higher intakes of vegetables and fruits are associated with a lower risk of certain human cancers. A biomarker of vegetable and fruit intake would be a valuable research tool. A cross-sectional study assessed the association between plasma carotenoid concentrations and intakes of vegetables and fruits. Plasma carotenoids (alpha-carotene, beta-carotene, lutein, beta-cryptoxanthin, and lycopene) were measured in 50 male and 49 female participants, aged 18-37 years, with a wide range of habitual vegetable and fruit intakes. Dietary intakes were assessed via a food frequency questionnaire. Intake of vegetables and fruits and high carotenoid foods were measured. The sum of the plasma carotenoids (excluding lycopene) was highly correlated with intake of total vegetables and fruits (r = 0.59). Of the individual plasma carotenoids, plasma alpha-carotene had the highest correlation with intakes of both total vegetables (r = 0.50) and total fruits (r = 0.58). Intakes of foods with high carotenoid contents were correlated with their corresponding plasma concentrations as follows: high beta-carotene foods (r = 0.41); high lutein foods (r = 0.46); and high lycopene foods (r = 0.11). Multiple regression analyses showed that intake of total vegetables and fruits was the most significant determinant of each plasma carotenoid except lycopene. The utility of combining the plasma carotenoids as biomarkers of vegetable and fruit intake was assessed by a stepwise regression of total vegetable and fruit intake on plasma carotenoids. Significant determinants of intake of total vegetables and fruits were alpha-carotene, beta-cryptoxanthin, lutein, and energy intake (R2 = 0.53).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Simultaneous determination of vitamins A and E and carotenoids in plasma by reversed-phase HPLC in elderly and younger subjects.

A reversed-phase high-performance liquid-chromatographic method for the simultaneous determination of retinol, alpha-tocopherol, alpha-carotene, beta-carotene, cryptoxanthin, lutein/zeaxanthin, and lycopene is described. This method was applied to plasma measurements in healthy young and elderly subjects. The plasma, deproteinized with ethanol, is extracted twice with n-hexane. After evaporation, the residue is dissolved in 50 microL of tetrahydrofuran and made up to 200 microL with ethanol. Samples (50 microL) are injected onto a 250 x 4.6 mm column of 5-microns-particle Spherisorb ODS1 (Phase Separations) that had been equilibrated with solvent mixture A:B (90:10 by vol) [A = 100 mmol/L ammonium acetate in methanol: acetonitrile (80:20 by vol) and B = 100 mmol/L ammonium acetate in water] at 2 mL/min. The analytes are eluted by running a 12-min linear gradient to 100% A; solvent A is then maintained for 10 min. Intrabatch CVs were 2.3%, 3.3%, 2.8%, 3.6%, 3.6%, and 3.0% for retinol, alpha-tocopherol, lutein/zeaxanthin, cryptoxanthin, lycopene, and beta-carotene, respectively. The corresponding interbatch CVs were 4.9%, 5.8%, 12.3%, 6.5%, 8.0%, and 3.4%.

Adult↗

PubMed1996

Dietary intake of specific carotenoids and vitamins A, C, and E, and prevalence of colorectal adenomas.

We determined whether intakes of the main dietary carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein plus zeaxanthin, and lycopene) and of vitamins A, C, and E were associated with the prevalence of colorectal adenomas among male and female members of a prepaid health plan in Los Angeles who underwent sigmoidoscopy (n = 488 matched pairs). Participants, ages 50-74 years, completed a 126-item semiquantitative food-frequency questionnaire and a non-dietary questionnaire from 1991 to 1993. In the univariate-matched analysis, alpha-carotene, beta-carotene (with and without supplements), beta-cryptoxanthin, lutein plus zeaxanthin, vitamin A (with and without supplements), and vitamin C (with and without supplements) were associated with a decreased prevalence of colorectal adenomas. After adjustment for intake of calories, saturated fat, folate, fiber, and alcohol, and for current smoking status, body mass index, race, physical activity, and use of nonsteroidal anti-inflammatory drugs, only beta-carotene including supplements was inversely associated with adenomas (odds ratio (OR), 0.6; 95% confidence interval (CI), 0.41.1; trend, P= 0.04; ORs compare highest to lowest quartiles0; vitamin C showed a weaker inverse association (OR, 0.8; 95% CI, 0.5-1.5; trend, P = 0.08); and the remaining compounds were no longer clearly associated with risk. After including beta-carotene with supplements and vitamin C simultaneously in the mutivariate model, the association of beta-carotene with supplements with adenomas was weakened (OR, 0.8; 95% CI, 0.5-1.3; trend P = 0.15), and vitamin C was no longer associated with risk. These data provide only modest support for a protective association of beta-carotene with colorectal adenomatous polyps.

Adenoma↗

PubMed1996

Plasma concentrations of carotenoids and tocopherols in male long-term tobacco chewers, smokers and nonusers.

Plasma carotenoid and tocopherol concentrations of men, aged 25 to 55 years, who were long-term chewers, smokers, or tobacco nonusers were determined. Tobacco users had either chewed (n = 11) or smoked (n = 23) for > 15 years. Nonusers (n = 10) had never smoked > 1 pack or chewed > 34 g. Food energy, mono- and poly-unsaturated and saturated fats, cholesterol, vitamin A, vitamin E, and carotenoid intakes of the three groups were not significantly different. Chewers and smokers reported consuming significantly less cryptoxanthin, found primarily in some fruits, and had significantly lower plasma cryptoxanthin levels than nonusers. Nonusers had significantly higher concentrations of plasma alpha-tocopherol than smokers; whereas those of chewers were intermediate. Nonusers had significantly higher concentrations of plasma gamma-tocopherol and total tocopherols than chewers or smokers. Plasma delta-tocopherol concentrations of the groups were not significantly different. Nonusers had significantly higher levels of beta-carotene than smokers but not chewers. Plasma lutein and lycopene concentrations of all groups were not significantly different. Dietary intakes of total carotenoids and tocopherols of the three groups were not significantly different, yet nonusers had higher plasma concentrations of total and most individual carotenoids and tocopherols than smokers with values for chewers being intermediate.

Adult↗

PubMedDate not supplied

Plasma levels of lipophilic antioxidants in very old patients with type 2 diabetes.

BACKGROUND: Experimental research indicates that oxidative stress is implicated in aging and in the pathogenesis of diabetes and its complications. This evidence is limited in elderly patients with non-insulin dependent diabetes, in which age- and disease-related production of reactive oxygen species might exert synergistic damaging effects on tissues and organs. METHODS: Plasma levels of lipid-soluble compounds with antioxidant properties including vitamin A, vitamin E and carotenoids (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha- and beta-carotene) were measured by HPLC in 72 elderly patients with non-insulin dependent diabetes (75.7+/-0.8 years, 40 F, 32 M) and in 75 age-matched controls (77.2+/-1.2 years, 48 F, 27 M). RESULTS: All compounds measured were significantly lower in plasma from diabetic patients as compared to controls (p<0.0001). Plasma levels of vitamins A and E and of carotenoids did not significantly correlate with dietary intake and lipid profile in both groups. In patients, significant inverse correlations were found between age and levels of vitamin E, beta-cryptoxanthin, lycopene and beta-carotene. CONCLUSIONS: We conclude that patients of very old age with Type 2 diabetes show a poor plasma status of vitamins A and E and carotenoids, which negatively correlates with age. Further studies are needed to explore the possible therapeutic role of lipid-soluble vitamin supplements in elderly diabetic subjects.

Aged↗