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PubMed2005

Do dietary lycopene and other carotenoids protect against prostate cancer?

To determine whether dietary intake of lycopene and other carotenoids has an etiological association with prostate cancer, a case-control study was conducted in Hangzhou, southeast China during 2001-2002. The cases were 130 incident patients with histologically confirmed adenocarcinoma of the prostate. The controls were 274 hospital inpatients without prostate cancer or any other malignant diseases. Information on usual food consumption, including vegetables and fruits, was collected by face-to-face interviews using a structured food frequency questionnaire. The risks of prostate cancer for the intake of carotenoids and selected vegetables and fruits rich in carotenoids were assessed using multivariate logistic regression, adjusting for age, locality, education, income, body mass index, marital status, number of children, family history of prostate cancer, tea drinking, total fat and caloric intake. The prostate cancer risk declined with increasing consumption of lycopene, alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin. Intake of tomatoes, pumpkin, spinach, watermelon and citrus fruits were also inversely associated with the prostate cancer risk. The adjusted odds ratios for the highest versus the lowest quartiles of intake were 0.18 (95% CI: 0.08-0.41) for lycopene, 0.43 (95% CI: 0.21-0.85) for alpha-carotene, 0.34 (95% CI: 0.17-0.69) for beta-carotene, 0.15 (95% CI: 0.06-0.34) for beta-cryptoxanthin and 0.02 (95% CI: 0.01-0.10) for lutein and zeaxanthin. The corresponding dose-response relationships were also significant, suggesting that vegetables and fruits rich in lycopene and other carotenoids may be protective against prostate cancer.

Carotenoids↗
PubMed2005

The role of diet and nutrition in cervical carcinogenesis: a review of recent evidence.

Our objective was to provide an update on recent epidemiologic evidence about the role of diet and nutrition on the risk of human papillomavirus (HPV) persistence and cervical neoplasia, taking HPV into account. We conducted a systematic review and qualitative classification of all observational studies controlling for HPV infection published between March 1995 and November 2003 and of all randomized clinical trials published between January 1991 and November 2003. Scientific evidence was classified as convincing, probable, possible or insufficient, as used in a previous study on diet and cancer. Thirty-three studies were eligible for this review (10 clinical trials, 8 observational prospective studies and 15 case-control studies). The few studies on HPV persistence showed a possible protective effect of fruits, vegetables, vitamins C and E, beta- and alpha-carotene, lycopene, luterin/zeaxanthin and cryptoxanthin. Evidence for a protective effect of cervical neoplasia was probable for folate, retinol and vitamin E and possible for vegetables, vitamins C and B12, alpha-carotene, beta-carotene, lycopene, lutein/zeaxanthin and cryptoxanthin. Evidence for an increased risk of cervical neoplasia associated with high blood homocysteine was probable. Results did not differ between studies looking at preneoplastic and invasive lesions or between retrospective and prospective studies. The available evidence for an association between diet and nutritional status and cervical carcinogenesis taking HPV infection into account is not yet convincing. Large cohort studies are needed to adequately assess the role of foods and nutrients in cervical HPV carcinogenesis.

Carotenoids↗
PubMed2006

Intake of the major carotenoids and the risk of epithelial ovarian cancer in a pooled analysis of 10 cohort studies.

Carotenoids, found in fruits and vegetables, have the potential to protect against cancer because of their properties, including their functions as precursors to vitamin A and as antioxidants. We examined the associations between intakes of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin and lycopene and the risk of invasive epithelial ovarian cancer. The primary data from 10 prospective cohort studies in North America and Europe were analyzed and then pooled. Carotenoid intakes were estimated from a validated food frequency questionnaire administered at baseline in each study. Study-specific relative risks (RR) were estimated using the Cox proportional hazards model and then combined using a random-effects model. Among 521,911 women, 2,012 cases of ovarian cancer occurred during a follow-up of 7-22 years across studies. The major carotenoids were not significantly associated with the risk of ovarian cancer. The pooled multivariate RRs (95% confidence intervals) were 1.00 (0.95-1.05) for a 600 microg/day increase in alpha-carotene intake, 0.96 (0.93-1.03) for a 2,500 microg/day increase in beta-carotene intake, 0.99 (0.97-1.02) for a 100 microg/day increase in beta-cryptoxanthin intake, 0.98 (0.94-1.03) for a 2,500 microg/day increase in lutein/zeaxanthin intake and 1.01 (0.97-1.05) for a 4,000 microg/day increase in lycopene intake. These associations did not appreciably differ by study (p-values, tests for between-studies heterogeneity >0.17). Also, the observed associations did not vary substantially by subgroups of the population or by histological type of ovarian cancer. These results suggest that consumption of the major carotenoids during adulthood does not play a major role in the incidence of ovarian cancer.

Breast Neoplasms↗
PubMed1998

Xanthophyll esters in human skin.

Carotenol fatty acid esters in various fruits and vegetables are sources of carotenoids for humans and are cleaved during intestinal absorption to yield the parent xanthophyll. In the present study we demonstrate that low amounts of carotenol esters are present in human skin. Eighteen different carotenol fatty acid esters were separated in extracts from human skin by means of reversed-phase high-performance liquid chromatography. After saponification of tissue samples, lutein, zeaxanthin, 2',3'-anhydrolutein, alpha-cryptoxanthin and beta-cryptoxanthin were identified as the major parent carotenoids. Based on comparison with synthetic reference compounds, several carotenol mono- and di-fatty acid esters were tentatively assigned, ranging from linoleate to stearate; the levels are low, in the range of pmol/g human skin, i.e. , several orders of magnitude lower than that of beta-carotene. Carotenol esters in human skin may be formed by reesterification of xanthophylls following absorption. Also, very small amounts of esters may circulate in the blood and subsequently accumulate in tissues such as skin.

Adult↗
PubMed1996

[Daily intake of carotenoids (carotenes and xanthophylls) from total diet and the carotenoid content of selected vegetables and fuit].

The recommended daily intake is currently either 2 mg of beta-carotene (recommended by DGE, Germany, in addition to 1.0 (0.8) mg retinol-equivalents for vitamin A requirement) or 5-6 mg of beta-carotene (recommended by NCI, USA). The present studies were carried out to investigate to what extent a balanced diet prepared using household or cafeteria methods contributes to achieve the desired intake. Beta-carotene and other carotenoids in the total daily diet samples were determined by RP-HPLC. In addition to beta-carotene, in decreasing quantity lutein, alpha-carotene, antheraxanthin, lycopene, zeaxanthin, neoxanthin, beta-cryptoxanthin, alpha-cryptoxanthin and violaxanthin were estimated. The intake of beta-carotene (carotenoids) ranged from 0.2 to 9.7 mg/d (0.7-16.5 mg/d) with mean values (median) of 1.1 mg/d for beta-carotene and 3.9 mg/d for carotenoids based on results from investigations of 39 total daily diet samples. The recommended daily intake can only be achieved by consuming (100-200 g/d) of vegetables und fruits with a particularly high carotenoid content. Kale (34.8), red peppers (27.4), parsley (25.7), spinach (17.3), lamb's lettuce (16.0), carrots (15.8) and tomatoes (12.7) headed the list of vegetables with more than 10 mg/100 g. In the case of fruit, papayas (3.8), grapefruits (3.6), nectarines (2.9) and apricots (2.6) were pre-eminent with more than 2 mg/ 100 g. The results distinguish between provitamin A and non-provitamin A carotenoids. In addition the contents of beta-carotene and lutein are shown.

Carotenoids↗
PubMed2003

QTL and candidate genes phytoene synthase and zeta-carotene desaturase associated with the accumulation of carotenoids in maize.

Carotenoids are a class of fat-soluble antioxidant vitamin compounds present in maize ( Zea mays L.) that may provide health benefits to animals or humans. Four carotenoid compounds are predominant in maize grain: beta-carotene, beta-cryptoxanthin, zeaxanthin, and lutein. Although beta-carotene has the highest pro-vitamin A activity, it is present in a relatively low concentration in maize kernels. We set out to identify quantitative trait loci (QTL) affecting carotenoid accumulation in maize kernels. Two sets of segregating families were evaluated-a set of F2:3 lines derived from a cross of W64a x A632, and their testcross progeny with AE335. Molecular markers were evaluated on the F2:3 lines and a genetic linkage map created. High-performance liquid chromatography was performed to measure beta-carotene, beta-cryptoxanthin, zeaxanthin, and lutein on both sets of materials. Composite interval mapping identified chromosome regions with QTL for one or more individual carotenoids in the per se and testcross progenies. Notably QTL in the per se population map to regions with candidate genes, yellow 1 and viviparous 9, which may be responsible for quantitative variation in carotenoids. The yellow 1 gene maps to chromosome six and is associated with phytoene synthase, the enzyme catalyzing the first dedicated step in the carotenoid biosynthetic pathway. The viviparous 9 gene maps to chromosome seven and is associated with zeta-carotene desaturase, an enzyme catalyzing an early step in the carotenoid biosynthetic pathway. If the QTL identified in this study are confirmed, particularly those associated with candidates genes, they could be used in an efficient marker-assisted selection program to facilitate increasing levels of carotenoids in maize grain.

Alkyl and Aryl Transferases↗
PubMed1996

Thermocryptoxanthins: novel intermediates in the carotenoid biosynthetic pathway of Thermus thermophilus

Various thermozeaxanthins are the end products of the carotenoid biosynthetic pathway of the thermophilic eubacterium Thermus thermophilus. These compounds are zeaxanthin glucoside esters. Carotenoid analysis and inhibitory studies led to the identification of most of the intermediates of the pathway: beta-carotene, beta-cryptoxanthin, zeaxanthin, and several new carotenoids. The intermediates, identified by various spectroscopic methods as beta-cryptoxanthin glucoside esters carrying fatty acid moieties of different chain lengths, were designated as thermocryptoxanthins. The use of the inhibitors diphenylamine and 2-(4-chlorophenylthio)-triethylamine-HCl resulted in the accumulation of the intermediates phytoene, lycopene, and gamma-carotene derivatives, which normally are present in amounts below the detection limit. The levels of non-esterified glycosides were extremely low. The results presented were used to establish the complete carotenoid biosynthetic pathway of T. thermophilus.

Journal Article↗
PubMed2003

Substrate specificity of the violaxanthin de-epoxidase of the primitive green alga Mantoniella squamata (Prasinophyceae).

The substrate specificity of the enzyme violaxanthin de-epoxidase (VDE) of the primitive green alga Mantoniella squamata (Prasinophyceae) was tested in in vitro enzyme assays employing the following xanthophyll mono-epoxides: antheraxanthin (Ax), diadinoxanthin (Ddx), lutein-epoxide (LE), cryptoxanthin-epoxide (CxE), 9- cis neoxanthin (cNx), all- trans neoxanthin (Nx), and xanthophyll di-epoxides: 9- cis violaxanthin (cVx), all- trans violaxanthin (Vx), cryptoxanthin-di-epoxide (CxDE). The data presented in this study show that the VDE of M. squamata not only exhibits a low affinity for the mono-epoxide Ax, as has been reported by R. Frommolt et al. (2001, Planta 213:446-456), but has a reduced substrate affinity for the mono-epoxides Ddx, LE, CxE, and Nx as well. On the other hand, xanthophylls with a second epoxy-group (Vx, CxDE) can be de-epoxidized with a higher efficiency. Such a preference for xanthophyll di-epoxides cannot be observed for the higher-plant VDE, where, in general, no marked differences in the pigment de-epoxidation rates between xanthophyll mono- and di-epoxides are visible. Despite this substantial difference between the VDEs of M. squamata and S. oleracea there are also features common to both enzymes. Neither VDE is able to convert xanthophylls with a 9- cis configuration in the acyclic polyene chain and both rely on substrates in the all- trans configuration. Both enzymes furthermore exhibit a dependence of enzyme activity on the polarity of the substrate. Highly polar (Nx) or non-polar (CxE) xanthophylls are de-epoxidized with greatly reduced rates in comparison to substrates with an intermediate polarity (Vx, Ax, LE, Ddx). This dependence on substrate polarity becomes more obvious when the higher-plant VDE is examined, as the substrate affinity of the VDE of M. squamata is more strongly influenced by the existence or absence of a second epoxy-group. In summary, the data presented in this study underline the fact that different VDEs, although in general catalyzing the same reaction sequence, are functionally diverse.

Chlorophyta↗
PubMed1993

Liquid chromatographic method for the determination of carotenoids, retinoids and tocopherols in human serum and in food.

A liquid chromatographic (LC) method has been developed for the quantitative measurement of the six major carotenoids in human serum (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and beta-carotene) as well as retinol, retinyl palmitate, alpha-tocopherol, gamma-tocopherol, and delta-tocopherol. Several polar carotenoids, 2',3'-anhydrolutein, alpha-cryptoxanthin, and geometric isomers of lycopene and beta-carotene are also separated. Retinoids and carotenoids are monitored using a programmable ultraviolet-visible detector, while tocopherols are monitored using a fluorescence detector. The method uses a gradient containing acetonitrile, methanol, and ethyl acetate. Ammonium acetate is introduced with the methanol to minimize carotenoid losses on the LC column aggravated by the use of acetonitrile and ethyl acetate. The method is also applicable to the analysis of foods.

Carotenoids↗
PubMed2006

Comparison of the serum ferritin and percentage of transferrin saturation as exposure markers of iron-driven oxidative stress-related disease outcomes.

BACKGROUND: Iron-catalyzed oxidative stress may be the primary mechanism for the pathogenesis of diseases related to iron excess. We hypothesized previously that certain markers of iron in bound form that are commonly used in epidemiologic studies might be inappropriate for investigating iron-related adverse health effects because oxidative stress requires iron in redox-active form. METHODS: To study aspects of this hypothesis, we examined the association between levels of serum ferritin or the percentage of transferrin saturation (%TS) and levels of serum antioxidant vitamins and C-reactive protein (CRP). This cross-sectional analysis included 11245 adults aged 20 years or older who participated in the Third National Health and Nutrition Examination Survey. RESULTS: Adjusted concentrations of serum alpha-carotene, beta-carotene, beta-cryptoxanthin, and lycopene were inversely correlated with the serum ferritin concentration (P for trend < .01), even within the lower deciles of the serum ferritin. In contrast, the %TS was significantly and positively associated with beta-cryptoxanthin, vitamin C, and vitamin E. In addition, the serum ferritin was positively associated but the %TS was strongly and inversely associated with the serum CRP (P for trend < .01). CONCLUSIONS: The serum ferritin and %TS showed contrasting associations with serum antioxidant vitamin levels and CRP although they have been used interchangeably in epidemiologic studies as markers of body iron. These results suggest that the %TS may not be a valid marker of exposure to iron-related oxidative stress. It appears that the serum ferritin is the preferred marker for assessment of clinical outcomes presumed to be caused by iron-related oxidative stress.

Adult↗
PubMed2006

Protective effects of plasma carotenoids on the risk of bladder cancer.

PURPOSE: We examined the associations between plasma micronutrients and bladder cancer risk, and evaluated the combined effects of carotenoid and cigarette smoke. MATERIALS AND METHODS: We performed a case-control study in 242 patients with bladder cancer and 204 healthy controls at Memorial Sloan-Kettering Cancer Center from 1993 to 1997. Epidemiological data and blood specimens were collected on 84 cases and 173 controls. Plasma micronutrients, including lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, beta-carotene, retinol, alpha-tocopherol and gamma-tocopherol, were determined by high performance liquid chromatography. The logistic regression model was used to estimate the effects from carotenoid, tocopherol and retinol on the risk of bladder cancer. RESULTS: Based on quartiles of plasma micronutrient levels and continuous variables, adjusted ORs were estimated for bladder cancer after controlling for potential confounders, including patient age, sex, education and pack-years of smoking. When using plasma levels of micronutrients as continuous variables, the adjusted OR was 0.22 (95% CI 0.05 to 0.92) for alpha-carotene, 0.42 (95% CI 0.18 to 1.00) for lutein, 0.16 (95% CI 0.02 to 1.06) for zeaxanthin, 0.94 (95% CI 0.89 to 0.99) for lycopene and 0.90 (95% CI 0.81 to 1.00) for beta-cryptoxanthin. The adjusted OR for the joint effect of plasma carotenoids and tobacco smoking was 6.22 (95% CI 1.87 to 20.8) in smokers with lower lutein and 5.18 (95% CI 1.57 to 17.1) in smokers with lower zeaxanthin. CONCLUSIONS: Our results show protective effects of carotenoids on bladder cancer. They suggest that bladder cancer may be a preventable disease through nutritional intervention, especially in smokers.

Carotenoids↗
PubMed1996

Influence of using different sources of carotenoid data in epidemiologic studies.

OBJECTIVE: This study compared distributions of carotenoid intake and diet-serum correlations using two sources of carotenoid data: the US Department of Agriculture-National Cancer Institute (USDA-NCI) carotenoid food composition database and values accompanying the Block-NCI Health Habits and History Questionnaire (HHHQ). DESIGN AND SUBJECTS: A 100-item food frequency questionnaire was used to collect dietary data from 2,152 adults, aged 43 to 85 years, who were participating in the Nutritional Factors in Eye Disease Study, a population-based study designed to evaluate nutritional factors associated with age-related eye disease. Blood samples were collected from a random sample of 400 nonfasting participants in the study. RESULTS: Median carotenoid intakes using HHHQ vs USDA-NCI data were alpha carotene (229 vs 223 micrograms/day), beta carotene (1,321 vs 1,325 micrograms/day), beta cryptoxanthin (72 vs 21 micrograms/day), lutein + zeaxanthin (653 vs 811 micrograms/day), and lycopene (593 vs 1,615 micrograms/day). all paired differences in carotenoid intake were significantly different from zero (Wilcoxon signed-rank, P < .0001). Despite these differences, the two databases similarly ranked individuals according to carotenoid intake: Spearman correlations ranged from .71 (lycopene) to .93 (alpha carotene). Differences between diet-serum correlations (adjusted for energy, body mass index, high density lipoprotein, and total cholesterol) using HHHQ vs USDA-NCI data were minor and not significant (P > .05): alpha carotene (r = .33 vs .32), beta carotene (r = .27 vs .32), beta cryptoxanthin (r = .48 vs .53), lutein+zeaxanthin (r = .28 vs .24), and lycopene (r = .29 vs .25). CONCLUSIONS: Although estimates of carotenoid intake differed significantly, only minor differences in carotenoid rankings and diet-serum correlations were observed using either data source in this population.

Adult↗
PubMed2000

Relationship between classic risk factors, plasma antioxidants and indicators of oxidant stress in angina pectoris (AP) in Tehran.

Cardiovascular disease (CVD) in general seems to be the leading cause of death in the Eastern Mediterranean Region (EMR) including Iran. This may be due to classic risk factors such as high triglyceride (TG), high total cholesterol (TC), and low levels of high density lipoprotein cholesterol (HDL-C). The impact of antioxidants as potentially protective risk factors against early coronary heart disease (CHD) is unknown in Iran. Therefore, relationships between angina and plasma antioxidants and indicators of lipid peroxidation were investigated in a case-control study. In this study, 82 cases of previously undiagnosed angina pectoris (AP), identified by a modified WHO Rose chest pain questionnaire and verified by electrocardiography during treadmill exercise testing, were compared with 146 controls selected from the same population of over 4000 male civil servants aged 40-60 years. Subjects with AP declared significantly less physical activity and had higher serum TG [means (S.E.M.) 2.32 (0.18) versus 1.61 (0.07) mmol/l] but lower HDL-C [1.01 (0.04) versus 1.18 (0.03) mmol/l] than age-matched controls. Levels of total serum cholesterol, low-density lipoprotein cholesterol (LDL-C) and lipoprotein(a) [Lp(a)] were not significantly different between the two groups, while the ratio of LDL-C/HDL-C was significantly higher [4.51 (0.23) versus 3.54 (0. 11)] for subjects with AP than for the controls. There was no significant difference in plasma levels of alpha-tocopherol, vitamin C, alpha- and beta-carotene. However, retinol [1.90 (0.06) versus 2. 09 (0.05)] and beta-cryptoxanthin [0.398 (0.04) versus 0.467 (0.03)] were significantly lower in AP. Furthermore, angina cases exhibited a higher index of lipid peroxidation than controls (e.g. malondialdehyde, MDA; 0.376 (0.010) versus 0.337 (0.009) micromol/l). On multiple logistic regression analysis, retinol with odds ratio (OR) of 0.644 [95% confidence interval (CI; 0.425-0.978)], beta-cryptoxanthin, with an OR of 0.675 (CI; 0.487-0.940), oxidation indices, MDA with OR of 1.612 (95% CI; 1.119-2.322) and LDL-C/HDL-C ratio with OR of 2.006 (95% CI; 1.416-2.849) showed the most significant independent associations with AP in this group of Iranians. In conclusion, the state of lipid peroxidation as well as the status of special antioxidants may be co-determinants of AP in Iran, in parallel with the influence of classical risk factors for cardiovascular disease.

Adult↗
PubMed2001

Plasma antioxidant vitamins and carotenoids and age-related cataract.

OBJECTIVE: To investigate the relationships between plasma concentrations of antioxidant vitamins and carotenoids and nuclear, cortical, and posterior subcapsular cataracts in a group of elderly men and women. DESIGN: Cross-sectional survey. PARTICIPANTS: Three hundred seventy-two men and women, aged 66 to 75 years, born and still living in Sheffield, England. METHODS: The Lens Opacities Classification System (LOCS) III was used to grade nuclear, cortical, and posterior subcapsular lens opacities. Fasting blood samples were taken to assess plasma concentrations of vitamin C, vitamin E, alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin, and beta-cryptoxanthin. MAIN OUTCOME MEASURES: Logistic regression analyses of the associations between plasma vitamin concentrations and cataract subtype, adjusting for age, gender, and other risk factors. RESULTS: After adjustment for age, gender, and other risk factors, risk of nuclear cataract was lowest in people with the highest plasma concentrations of alpha-carotene (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.3-0.9, P for trend 0.006) or beta-carotene (OR, 0.7; 95% CI, 0.4-1.4, P for trend 0.033). Risk of cortical cataract was lowest in people with the highest plasma concentrations of lycopene (OR, 0.4; 95% CI, 0.2-0.8, P for trend 0.003), and risk of posterior subcapsular cataract was lowest in those with higher concentrations of lutein (OR, 0.5; 95% CI, 0.2-1.0, P for trend 0.012). High plasma concentrations of vitamin C, vitamin E, or the carotenoids zeaxanthin and beta-cryptoxanthin were not associated with decreased risk. CONCLUSIONS: These findings suggest that a diet rich in carotenoids may protect against cataract development, but because they are based on observational data, they need to be confirmed in randomized controlled trials.

Aged↗
PubMed2002

The influence of cigarette smoking on circulating concentrations of antioxidant micronutrients.

Cigarette smoke is a significant source of oxidative stress, one potential mechanism for its untoward health effects. The antioxidant defense system is partly comprised of antioxidant micronutrients, making it important to understand the relationship between cigarette smoking and circulating concentrations of antioxidant micronutrients. A synthesis of the literature shows that compared with nonsmokers, on average, active smokers have greater than 25% lower circulating concentrations of ascorbic acid, alpha-carotene, beta-carotene, and cryptoxanthin. The differences in blood concentrations of these micronutrients in former smokers is intermediate between never and current smokers, but average circulating concentrations of alpha-carotene, beta-carotene, and cryptoxanthin were 16-22% lower in former smokers compared with never smokers. Differences in dietary habits between smokers and nonsmokers could potentially account for these associations. Dietary micronutrient intake is associated with blood micronutrient concentrations. Furthermore, patterns of micronutrient consumption by smoking status mimic the pattern of associations observed for blood concentrations. For example, when pooled across studies intake of vitamin C was 16% lower in current smokers and 2% lower in former smokers than in never smokers; the corresponding figures for beta-carotene were 17 and 4%, respectively. Despite the strong potential for confounding, the differences observed between current smokers and nonsmokers seem to be due to an acute effect of smoking based on results of studies of smoking and antioxidant micronutrient concentrations that have either adjusted for dietary antioxidant micronutrient intake and other potential confounding factors or documented short term changes in circulating antioxidant micronutrient concentrations in smokers before and after smoking cigarettes. The associations observed with active smoking also appear to hold true for passive smoking, implying that even low-dose exposures to tobacco smoke can result in lowered circulating antioxidant micronutrient concentrations. Smoking was more weakly associated with circulating concentrations of vitamin E and the nonprovitamin A carotenoids lutein/zeaxanthin and lycopene. The combined evidence supports the conclusion that cigarette smoking is independently associated with lowered circulating concentrations of ascorbic acid and provitamin A carotenoids. These associations have implications for the design and interpretation of epidemiologic studies of antioxidant micronutrients in relation to health and disease. To the extent that these micronutrients are associated with health and longevity, this evidence documents yet another deleterious consequence of cigarette smoking on human health.

Antioxidants↗
PubMed1999

Serum alpha- and gamma-tocopherols, retinol, retinyl palmitate, and carotenoid concentrations in captive and free-ranging bottlenose dolphins (Tursiops truncatus).

Concentrations of retinol, retinyl palmitate, beta-carotene, alpha-carotene, cryptoxanthin, lutein, lycopene, alpha-tocopherol, and gamma-tocopherol were measured in blood samples collected from 15 captive and 55 free-ranging bottlenose dolphins (Tursiops truncatus). From June 1991 to June 1994, blood samples were collected from captive animals residing at two locations; at Seven Seas (Brookfield Zoo, Brookfield, IL) and Hawk's Cay (Marathon Key, FL). Blood samples were collected from free-ranging animals from June 1991 to June 1996. Retinol levels were not significantly different between captive dolphin groups. However, Seven Seas animals had higher (P < 0.01) serum retinol concentrations compared to free-ranging animals (0.061 vs 0.041 microgram/ml). Retinyl palmitate was not detected in the serum of captive or free-ranging dolphins. Alpha-tocopherol levels were significantly (P < 0.05) higher for Seven Seas dolphins (16.4 micrograms/ml) than for Hawk's Cay (13.0 micrograms/ml) and free-ranging dolphins (12.5 micrograms/ml). Gamma-tocopherol concentrations were similar among captive and free-ranging dolphins. Free-ranging dolphins showed levels of circulating carotenoids (lutein and beta-carotene) while the captive animals did not. Additional carotenoids (lycopene, alpha-carotene and cryptoxanthin) were analyzed but not detected in any samples. Serum vitamin differences between captive and free-ranging dolphins may reflect the natural diet or indicate some potential biological or nutritional status significance.

Animals↗
PubMed1998

Determination of trans-beta-carotene and other carotenoids in blood plasma using high-performance liquid chromatography and thermal lens detection.

Thermal lens spectrometry (TLS) was applied for the detection of beta-cryptoxanthin, alpha-carotene, trans-beta-carotene, and lycopen in blood plasma. This combined high-performance liquid chromatography-TLS (HPLC-TLS) method was validated by comparison with HPLC-UV-Vis analysis of blood plasma under identical chromatographic conditions and by comparing the results obtained from an independent, standard HPLC procedure for determination of carotenoids in blood plasma samples. The results demonstrated good agreement with the target values for carotenoids in an in-laboratory control sample and confirmed the accuracy of the HPLC-TLS technique. Limits of detection for blood plasma samples were 70 pg/ml for beta-cryptoxanthin, 85 pg/ml for alpha-carotene, 100 pg/ml for trans-beta-carotene, and 120 pg/ml for lycopen. This represents a 100-fold improvement compared to the HPLC analysis with UV-Vis detection.

Carotenoids↗
PubMed2003

Plasma carotenoids, retinol, tocopherols, and lipoproteins in preeclamptic and normotensive pregnant Zimbabwean women.

BACKGROUND: We examined the relationship between maternal plasma lipoprotein and antioxidant status with risk of preeclampsia among women delivering at Harare Maternity Hospital, Zimbabwe. METHODS: One hundred seventy-three pregnant women with preeclampsia and 186 controls were included in a case-control study. Maternal plasma total cholesterol, high-density lipoprotein (HDL), and total triglycerides were measured using enzymatic methods. Plasma carotenoids (alpha-carotene, beta-carotene, lycopene, lutein, beta-cryptoxanthin, zeaxanthin), retinol, and tocopherols (alpha-tocopherol and gamma-tocopherol) were determined using high performance liquid chromatography. We used logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Preeclampsia risk increased with successively higher quartiles of plasma triglyceride (OR: 1.00, 1.70, 2.00, 5.26, with the lowest quartile as referent; P for trend <.001). We noted an inverse association between preeclampsia risk and HDL cholesterol concentrations (OR: 1.00, 0.87, 0.66, 0.68, with the first quartile as the referent group; P for trend =.169), although the trend was not statistically significant. After adjusting for confounders, we noted decreases in preeclampsia risk with increasing concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, and zeaxanthin, respectively. Women with beta-carotene concentrations in the highest quartile, as compared with those in the lowest quartile experienced a 50% decreased risk of preeclampsia (OR = 0.50, 95% CI 0.25-1.00). There was no clear pattern of preeclampsia risk with lycopene concentrations or with concentrations of gamma- and alpha-tocopherol. CONCLUSIONS: Our results are consistent with some, although not all, previous reports. Prospective studies are needed to determine the temporal relationship between observed alterations in lipid and antioxidant concentrations in preeclamptic pregnancies.

Adult↗