SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
The carotenoid pigments of the ripe and unripe fruits of Asparagus officinalis were investigated by means of an HPLC technique. Capsanthin, capsorubin, capsanthin 5,6-epoxide, antheraxanthin, violaxanthin, neoxanthin, mutatoxanthin epimers, zeaxanthin, lutein, beta-cryptoxanthin, beta-carotene, and some cis isomers were found. Carotenoids with 3,5,6-trihydroxy and 3,6-epoxy beta-end groups could not be deleted.
The structure of a novel major carotenoid glycoside (nearly 80% of total carotenoids) from a newly isolated bacterium, Paracoccus schoinia NBRC 100637T, was determined to be adonixanthin diglucoside using spectral data. By contrast, carotenoid diglycosides are rare and are usually minor carotenoids in nature. The minor carotenoids in this bacterium included astaxanthin diglucoside, zeaxanthin diglucoside, canthaxanthin, echinenone, zeaxanthin, beta-cryptoxanthin, and beta-carotene.
The novel ester (E)-phytol (5Z,8Z,11Z,14Z,17Z)-eicosapentaenoate++ + (1); (6Z,9Z,12Z,15Z)-hexadecatetraenoic acid; (6Z,9Z,12Z,15Z)-octadecatetraenoic acid; and (6Z,9Z,12Z)-hexadecatrienoic acid isolated from the diatom Navicula delognei f. elliptica, show significant antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhimurium, and Proteus vulgaris. beta-Carotene, alpha-cryptoxanthin, fucoxanthin, lutein, trans-phytol, and plastoquinone-9 were also isolated from this diatom.
To evaluate the role of nutritional factors in the etiology of endometrial cancer, we performed a case-cohort analysis using data from women enrolled in the National Breast Screening Study in Canada from 1980 to 1985. For this analysis, a subcohort was constructed by selecting a 10% random sample from the 56,837 women in the dietary cohort. Cases were the 221 women diagnosed with incident adenocarcinoma of the endometrium during follow-up to December 31, 1993 and ascertained by record linkage to the Canadian Cancer Database. Information on usual diet at enrollment and other epidemiological variables was collected by means of self-administered questionnaires. Hazard ratios were obtained from proportional hazards regression models, with estimation of robust standard errors. We found a strong association of endometrial cancer with body mass index > 25 kg/m2 (hazard ratio 2.72, 95% CI: 2.06-3.50). Endometrial cancer risk was not associated significantly with intakes of total energy, carbohydrates, proteins, total fat and major fatty acids, total dietary fiber and various types of fibers, vitamin C, E and A, folic acid, beta-carotene, lutein, or cryptoxanthin. Some decrease in risk was noted with relatively high intakes of saturated fat, animal fat or lycopene. The associations observed in the study were independent of total energy intake and most non-dietary risk factors. The study suggests that dietary intakes of energy and most major nutrients are not related to the risk of endometrial cancer among Canadian women.
OBJECTIVE: To investigate the association between dietary carotenoid intake and lung cancer risk in women. METHODS: A case-cohort study was undertaken in the Canadian National Breast Screening Study dietary cohort, which consists of 56,837 women who completed a self-administered dietary questionnaire. The cohort was recruited between 1980 and 1985, and during follow-up to the end of 1993 a total of 196 cohort members were diagnosed with incident lung cancer. For analysis, a subcohort consisting of a random sample of 5681 women was selected from the full dietary cohort. After exclusions for various reasons, the analyses were based on 155 cases and 5,361 non-cases. RESULTS: When compared to those in the lowest quartile level of intake, the adjusted incidence rate ratios (95% confidence intervals) for those in the highest quartile levels of alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein intake were 0.90 (0.51-1.58). 1.40 (0.76-2.59), 0.66 (0.33-1.32), 1.04 (0.61-1.76), and 1.26 (0.70-2.24), respectively; none of the associated tests for trend was statistically significant. CONCLUSION: These results suggest that there is no association between dietary carotenoid intake and lung cancer risk. at least for the range of intakes observed here.
Although a wealth of research has focused on the influence of diet on breast cancer risk, the relationships between dietary factors and tumor characteristics of breast cancer, like estrogen receptor (ER) status, are not well characterized. In a case-case study, we evaluated self-reported dietary intake for five individual carotenoids, selected fatty acids, and cholesterol 1 year before diagnosis in 34 premenopausal breast cancer patients with ER-negative tumors and 86 premenopausal breast cancer patients with ER-positive tumors from The University of Texas M. D. Anderson Cancer Center. In multivariate logistic regression analysis adjusted for age, body mass index, and ethnicity, high intakes of linoleic acid were associated with more than a threefold greater risk of ER-negative disease than ER-positive disease (odds ratio (OR) = 3.48, 95% confidence interval (CI) = 1.42-8.54), whereas high cholesterol intake was associated with lower risk of ER-negative disease (OR = 0.35, 95% CI = 0.14-0.92). In a model evaluating carotenoids, selected fatty acids, and cholesterol together, the association with high intake of linoleic acid remained statistically significant (OR = 3.96,95% CI = 1.53-10.25), while those for high intake of cholesterol (OR = 0.38, 95% CI = 0.14-1.03) and low intake of cryptoxanthin (OR = 0.43, 95% CI = 0.17-1.06) were of marginal significance. While no striking associations were observed for the intakes of total carotenoids, selected fatty acids, and cholesterol, our analysis revealed an association for the consumption of a specific fatty acid (i.e., linoleic acid), suggesting dietary influence of this factor on ER status in premenopausal breast cancer patients. However, larger studies are needed to clarify the role of micronutrients in ER status in breast cancer.
Various natural carotenoids, besides beta-carotene, were proven to have anticarcinogenic activity, and some of them showed more potent activity than beta-carotene. Thus, these carotenoids (alpha-carotene, lutein, zeaxanthin, lycopene, beta-cryptoxanthin, fucoxanthin, astaxanthin, capsanthin, crocetin and phytoene), as well as beta-carotene, may be useful for cancer prevention. In the case of phytoene, the concept of 'bio-chemoprevention', which means biotechnology-assisted method for cancerchemoprevention, may be applicable. In fact, establishment of mammalian cells producing phytoene was succeeded by the introduction of crtB gene, which encodes phytoene synthase, and these cells were proven to acquire the resistance against carcinogenesis. Antioxidative phytoene-containing animal foods may be classified as a novel type of functional food, which has the preventive activity against carcinogenesis, as well as the ability to reduce the accumulation of oxidative damages, which are hazardous for human health.
OBJECTIVE: To examine the effect of specific dietary carotenoids and their primary plant food sources on lung cancer risk in a population-based case-control study of women. METHODS: Data were available for 587 incident primary lung cancer cases and 624 controls frequency matched to cases based on age. A modified version of the 100-item NCI-Block food-frequency questionnaire was used to obtain information concerning usual diet 2-3 years prior to interview. RESULTS: In models adjusted for age, total calorie intake, pack-years of smoking, and education, beta-carotene, beta-cryptoxanthin, lutein + zeaxanthin, and total carotenoid intake were each associated with a significantly lower risk of lung cancer. Several vegetable groups were predictive of lower lung cancer risk, particularly the frequency of total vegetable intake. Individual and total carotenoids were no longer significantly associated with lower lung cancer risk in models adjusted for total vegetable intake. However, total vegetable intake remained significantly inversely associated with risk in models adjusted for total carotenoids. CONCLUSIONS: These results indicate that consumption of a wide variety of vegetables has a greater bearing on lung cancer risk in a population of smoking and nonsmoking women than intake of any specific carotenoid or total carotenoids.
OBJECTIVE: Data have suggested that higher levels of nutrients are protective against HPV persistence and cervical neoplasia. This study assessed the role of circulating nutrients on clearance of oncogenic HPV infections. METHODS: Women were followed prospectively with visits at baseline and approximately 4- and 10-months post-baseline. At each visit, 15 oncogenic HPV types were determined. Plasma levels were assessed at the 4-month visit for retinol, carotenoids (i.e., alpha-, trans-beta-, cis-beta-carotene, alpha-, beta-cryptoxanthin, lutein, zeaxanthin, trans- and cis-lycopene), tocopherols (i.e., alpha-, delta-, and gamma-tocopherol), folate and vitamin B12. Using multivariate Cox proportional hazards models, time to clearance analyses of oncogenic HPV infections were conducted for 84 women with at least one oncogenic infection at baseline. Hazard ratios (HR) were estimated for the association of HPV clearance to each nutrient tertile and to determine linear trends. RESULTS: The likelihood of clearing an oncogenic HPV infection was significantly higher with increasing levels of trans-lycopene (p for trend, 0.025) and cis-lycopene (p for trend, 0.010). The adjusted hazard ratios of the highest tertiles of trans- and cis-lycopene were 2.79 (95% CI = 1.17-6.66) and 2.92 (95% CI = 1.28-6.63) compared with the lowest tertiles. CONCLUSIONS: Higher concentrations of trans- and cis-lycopene may reduce the time to clearance of an oncogenic HPV infection.
A prospective survey was conducted in a random sample of smokers (SMO) and non-smokers (NON) men living in Havana. The aim of the survey was to investigate metabolic and dietary parameters discriminating between SMO and NON volunteers, which could explain underlying mechanisms to the higher risk of Epidemic Neuropathy (51,000 reported cases in Cuba from late 1991) previously demonstrated in the Cuban smoker. Forty three blood markers were determined and dietary intakes evaluated during 4 seasonal periods. alpha-carotene, beta-carotene, beta-cryptoxanthin, total carotenoids and riboflavin blood concentrations were lower in SMO vs. NON subjects. Activities of glutathione reductase and butryrylcholinesterase were lower in the SMO group, as did total protein levels. Copper and thiocyanates were higher in SMO subjects. Most of the dietary parameters did not differ between the two groups of volunteers. Low biologically available quantities of carotenoids and riboflavin from low dietary intakes and depletion through smoking would be the main precipitating factors of Epidemic Neuropathy. Protein depletion and copper delivery via tobacco smoke, sunlight exposure, level of physical activity and high consumption of cigarettes, in a context of low dietary supplies concerning especially B vitamins, were probably aggravating factors through oxidative stress and impairment of cyanide detoxification.
We conducted a cross-sectional pilot study on healthy pre-menopausal women (aged 45-50 years) living in Granada, in the south of Spain (n = 39) and Malmö, in the south of Sweden (n = 38) in order to compare their plasma carotenoid levels and to investigate the relationship between the differences in food consumption. Plasma concentrations of six carotenoids were measured using high performance liquid chromatography, habitual diet (at individual level) was estimated by food frequency questionnaires and 24-hour diet recalls were used for standardised measurement of diet at group-level. We found that women in Granada consumed more fruit and vegetables than women in Malmö. Plasma concentrations of beta-cryptoxanthin, lycopene, zeaxanthin, total carotenoids and alpha-tocopherol were higher in Granada than in Malmö, although plasma concentrations of alpha-carotene and retinol were higher in Malmö. Both within and between study centres, consumption of fruit and vegetables correlated positively with plasma concentrations of different carotenoids. The study showed that differences in consumption of fruit and vegetables between the two European centres were reflected in plasma carotenoid concentrations.
The purpose of this study was to investigate whether a relationship exists between mortality rates and serum antioxidant levels among Japanese inhabitants. The follow-up subjects, who participated in comprehensive health examinations, consisted of 2444 inhabitants (949 males and 1495 females) of a rural area in Hokkaido, Japan. Between 1991 and December 2000, 146 subjects (94 males and 52 females) died, with cancer accounting for 76 of these deaths (48 males and 28 females). Serum samples at fasting were collected at entry into the study, and serum levels of beta- and alpha-carotenes, lycopene, beta-cryptoxanthin, canthaxanthin, zeaxanthin/lutein, tocopherols, and retinol were measured separately by high-performance liquid chromatography (HPLC). The statistical analyses were conducted using the Cox proportional hazard model. Age- and gender-adjusted hazard ratios of the groups with high serum levels of lycopene, beta-carotene, zeaxanthin/lutein, and total carotenoids compared to those with low serum levels were 0.36 (95% C.I: 0.19-0.69), 0.53 (0.29-0.95), 0.73 (0.43-1.25), and 0.52 (0.30-0.92) for cancers of all sites, and 0.44 (95% C.I: 0.28-0.69), 0.59 (0.39-0.90), 0.61 (0.40-0.93), and 0.50 (0.33-0.76) for all causes, respectively. Similar results were found after adjusting for gender, age, smoking habits, alcohol consumption, and serum levels of total cholesterol and glutamic pyruvic transaminase (GPT) activity. Moreover, after excluding mortality within the first three years of follow-up, the hazard ratios of subjects with high serum levels of lycopene, total carotenes, and total carotenoids were significantly and inversely associated with subsequent mortality from all causes and cancers of all sites after adjusting for gender, age, and serum levels of total cholesterol, alpha-tocopherol, and retinol. These results suggest that high serum levels of antioxidants, such as lycopene, beta-carotene and zeaxanthin/lutein, play roles in preventing death from cancer and from all causes. However, high serum levels of tocopherols and retinol did not demonstrate clear associations with either low mortality rates from all causes or cancer of all sites.
The aim of this study was to elucidate any association between oral lichen planus (OLP) and serum antioxidant micronutrients by a population-based case-control study. A total of 9536 subjects were examined, and 62 (58 reticular, 4 atrophic and erosive) diagnosed with OLP at referral facilities were compared with four controls per case (n=248) selected among disease-free subjects matched for age and sex. Serum levels of micronutrients (retinol, alpha-tocopherol, zeaxanthin/lutein and cryptoxanthin, lycopene, alpha-carotene and beta-carotene) were estimated by the high performance liquid chromatography (HPLC) method. Among cases, mean serum retinol level (2.820+/-0.849 micromol/l) was significantly higher compared with that of controls (2.562+/-0.735 micromol/l) (P<0.05). No significant differences were noted in carotenoid levels examined in this study, except for a lower level of lycopene found in atrophic/erosive OLP cases. The results of this study suggest that low serum retinol or carotenoid levels are not risk factors for occurrence of lichen planus, and any specific benefits of antioxidant micronutrients cannot be claimed for this inflammatory disorder.
We examined the relation between dietary fruit and vegetables, carotenoids and vitamin intakes and the risk of bladder cancer among male smokers in a prospective cohort study. Over a median of 11 years, we followed 27 111 male smokers aged 50-69 years who were initially enrolled in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study. During this period, 344 men developed bladder cancer. All of these men had completed a 276-food item dietary questionnaire at baseline. Cox proportional hazards models were used to estimate the relative risks and 95% confidence intervals and to simultaneously adjust for age, smoking history, energy intake and intervention group. Consumption of fruits and vegetables was not associated with the risk of bladder cancer (relative risk=1.28; 95% confidence intervals CI: 0.89-1.84, for highest vs lowest quintile). Similarly, no associations were observed for groups of fruits or vegetables (berries and cruciferous vegetables), or for specific fruits and vegetables. Dietary intakes of alpha-carotene, beta-carotene, lycopene, lutein/zeaxanthin, beta-cryptoxanthin, vitamins A, E, and C, and folate were not related to the risk of bladder cancer. These findings suggest that fruit and vegetable intakes are not likely to be associated with bladder cancer risk. However, these results may not be generalisable to non-smokers.
Despite declining incidence rates, gastric cancer (GC) is a major cause of death worldwide. Its aetiology may involve dietary antioxidant micronutrients such as carotenoids and tocopherols. The objective of this study was to determine the association of plasma levels of seven common carotenoids, their total plasma concentration, retinol and alpha- and gamma-tocopherol, with the risk of gastric adenocarcinoma in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), a large cohort involving 10 countries. A secondary objective was to determine the association of total sum of carotenoids, retinol and alpha-tocopherol on GCs by anatomical subsite (cardia/noncardia) and histological subtype (diffuse/intestinal). Analytes were measured by high-performance liquid chromatography in prediagnostic plasma from 244 GC cases and 645 controls matched by age, gender, study centre and date of blood donation. Conditional logistic regression models adjusted by body mass index, total energy intake, smoking and Helicobacter pylori infection status were used to estimate relative cancer risks. After an average 3.2 years of follow-up, a negative association with GC risk was observed in the highest vs the lowest quartiles of plasma beta-cryptoxanthin (odds ratio (OR) = 0.53, 95% confidence intervals (CI) = 0.30-0.94, P(trend) = 0.006), zeaxanthin (OR = 0.39, 95% CI = 0.22-0.69, P(trend) = 0.005), retinol (OR = 0.55, 95% CI = 0.33-0.93, P(trend) = 0.005) and lipid-unadjusted alpha-tocopherol (OR = 0.59, 95% CI = 0.37-0.94, P(trend) = 0.022). For all analytes, no heterogeneity of risk estimates or significant associations were observed by anatomical subsite. In the diffuse histological subtype, an inverse association was observed with the highest vs lowest quartile of lipid-unadjusted alpha-tocopherol (OR = 0.26, 95% CI = 0.11-0.65, P(trend) = 0.003). These results show that higher plasma concentrations of some carotenoids, retinol and alpha-tocopherol are associated with reduced risk of GC.
The relationships between risk of cervical dysplasia and dietary and serum carotenoids and vitamins were investigated in a case-control study. Cases were 156 women who attended Papanicolaou test screening in nine institutes affiliated with Japan Study Group of Human Papillomavirus (HPV) and Cervical Cancer and had cervical dysplasia newly histologically confirmed. Age-matched controls were selected from women with normal cervical cytology attending the same clinic. Blood sample and cervical exfoliated cells were obtained for measuring serum retinol, alpha-carotene, beta-carotene, zeaxanthin/lutein, cryptoxanthin, lycopene and alpha-tocopherol and for HPV detection. Higher serum level of alpha-carotene was significantly associated with decreased risk of cervical dysplasia after controlling for HPV infection and smoking status (odds ratio (OR) = 0.16, 95% confidence interval (CI) 0.04-0.62 for the highest as compared with the lowest tertile). Decreased risk for the highest tertile of serum lycopene (OR = 0.28) was marginally significant. Decreased risks observed for the highest tertiles of beta-carotene (OR = 0.65) and zeaxanthin/lutein (OR = 0.53), were not statistically significant.
OBJECTIVES: (1) To compare tissue and plasma carotenoids status of healthy subjects and subjects with pre-cancer and cancer lesions; (2) to evaluate the effect of beta-carotene supplementation on the concentrations of other carotenoids in tissue (luteine + zeaxanthin, cryptoxanthin, lycopene, alpha-carotene) and in plasma and also retinol and alpha-tocopherol levels. DESIGN: Eighteen subjects were divided into three groups on the basis of colonoscopy and histological analytical findings: four healthy subjects (control group A); seven subjects affected by adenomatous polyps (group B with pre-cancer lesions); seven subjects suffering from colonic cancer (group C). Blood and colonic biopsy samples were taken (of colon and rectal mucosa) before and after beta-carotene supplementation in all subjects. Groups A and B received a daily dose of beta-carotene (30 mg/die) for 43 d. Group C's supplementation was terminated at the time which was performed, usually within 15 d. The tissue and plasma concentration of carotenoids, retinol and alpha-tocopherol were determined by high-performance liquid chromatography. RESULTS: The tissue concentrations of each carotenoid were similar in all the intestinal sites examined as regards groups A and B, although there was a high degree of intra individual variability within each group. Only beta-carotene made significant increases (P < 0.001) after supplementation. The subjects with cancer show tissue levels for each carotenoid lower than those of healthy subjects or subjects with polypous. The plasma levels of alpha-tocopherol did not change after supplementation while significant increases were noted of retinol, alpha-carotene (P < 0.01) and of beta-carotene (P < 0.001). CONCLUSIONS: The patients with colonic cancer seemed to undergo a significant reduction in their antioxidant reserves with respect to the normal subjects and or polyps. We can confirm that oral B-carotene supplementation induces also an increase in plasma alpha-carotene in all groups.
OBJECTIVE: To assess the status of lipidsoluble antioxidants (carotenoids, tocopherols, ubiquinone), retinol and their correlation with TRAP (total radical-trapping antioxidant potential) in patients with Crohn's disease. DESIGN: Prospective case-control study. SETTING: Clinic of Internal Medicine IV/Department of Gastroenterology and Hepatology, University of Vienna Medical School. SUBJECTS/METHODS: Plasma antioxidant concentrations were determined in patients with Crohn's disease (n = 24) to evaluate the antioxidant capacity compared to healthy controls (n = 33). Additionally, plasma TRAP (total radical-trapping antioxidant potential) was measured in 13 patients and 22 controls. RESULTS: All investigated carotenoids (alpha-carotene, beta-carotene and cryptoxanthin) were significantly decreased in patients with Crohn's disease (10.2 +/- 9.3, 16.2 +/- 12.4 and 7.8 +/- 5.5 microg/dl) compared to controls (13.3 +/- 5.1, 34.7 +/- 18.8 and 48.5 +/- 38.4 microg/dl respectively), whereas gamma-tocopherol and ubiquinone were significantly elevated in patients (0.14 +/- 0.07 microg/dl and 82.3 +/- 41.5 microg/dl, controls: 0.09 +/- 0.04 microg/dl and 60.8 +/- 30.0 microg/dl, respectively). Retinol and alpha-tocopherol did not significantly differ from controls. The total radical-trapping antioxidant potential (TRAP) was significantly lower in patients (1.11 +/- 0.28 micromol/l) compared to controls (1.34 +/- 0.26 micromol/l). Antioxidants were neither related to duration or severity of disease nor to disease activity. CONCLUSIONS: In patients with Crohn's disease several plasma antioxidant parameters are altered and the total radical-trapping antioxidant potential is decreased.