Determination of Individual Carotenoids in Human Plasma by High Performance Liquid Chromatography

Vegetable Gardening and Health Outcomes in Older Cancer Survivors: A Randomized Clinical Trial

Importance

Cancer survivors experience accelerated functional decline that threatens independence and quality of life. Previous studies have suggested that vegetable gardening may improve diet, physical activity, and physical function in this vulnerable population, which comprises more than 5% of the US population.

Objective

To assess whether diet, physical activity and functioning, and other outcomes improved in older cancer survivors assigned to a vegetable gardening intervention compared with a waitlist.

Design, Setting, and Participants

From May 11, 2016, to May 2, 2022, a 2-arm, assessor-blinded, crossover-designed, intent-to-treat, randomized clinical trial was conducted at cancer survivors' homes across Alabama. Medicare-eligible survivors of cancers with 5-year survival of 60% or more were registry ascertained and screened for suboptimal vegetable and fruit consumption (<5 servings per day), physical activity (<150 moderate-to-vigorous minutes per week), and physical function (36-Item Short Form Health Survey [SF-36] subscale score ≤90). Consented participants underwent baseline assessments, were randomly assigned to intervention or waitlisted arms, and were reassessed at 1-year follow-up.

Intervention

One-year, home-based vegetable gardening intervention providing gardening supplies and mentorship by cooperative extension-certified master gardeners to plant and maintain spring, summer, and fall gardens. Waitlisted participants received the identical intervention after 12 months.

Main Outcomes and Measures

The main outcome was a composite index of improvements in self-reported vegetable and fruit consumption, physical activity, and physical function corroborated by plasma α-carotene levels, accelerometry, and physical performance assessments, respectively.

Results

Of 381 enrolled participants (mean [SD] age, 69.8 [6.4] years; range, 50-95 years; 263 [69.0%] female), 194 were assigned to the gardening intervention and 187 were waitlisted (attrition rates, 7.2% and 7.0%, respectively). Intent-to-treat analyses did not detect a significant improvement in the composite index of vegetable and fruit intake, moderate-vigorous physical activity, and physical function (intervention arm vs waitlisted arm, 4.5% vs 3.1%; P = .53) or between-arm differences in vegetable and fruit intake (mean difference, 0.3 [95% CI, -0.1 to 0.7] servings per day; P = .10). The intervention arm experienced a significant improvement in vegetable and fruit intake (mean increase, 0.3 [95% CI, 0.0-0.6] servings per day; P = .04). Significant improvements also were observed in the intervention arm vs waitlisted arm in physical performance (mean difference for 2-minute step test, 6.0 [95% CI, 0.8-11.2] steps; P = .03; for 30-second chair stand, 0.8 [95% CI, 0.1-1.5] repetitions; P = .02), perceived health (8.4 [95% CI, 3.0-13.9] points on a 100-point scale [higher scores indicate better health]; P = .003), and gut microbiome alpha diversity (84.1 [95% CI, 20.5-147.6] more observed species; P = .01). The COVID-19 pandemic significantly moderated effects (eg, odds of improvement in self-reported physical functioning were greater before vs during the pandemic: odds ratio, 2.17; 95% CI, 1.12-4.22; P = .02).

Conclusions and Relevance

In this randomized clinical trial including older cancer survivors, a vegetable gardening intervention did not significantly improve a composite index of diet, physical activity, and physical function; however, survivors assigned to the intervention had significantly increased vegetable and fruit consumption and, compared with waitlisted survivors, experienced significant improvements in perceived health and physical performance. Further study in broader populations and during pandemic-free periods is needed to determine definitive benefits.

Trial Registration

ClinicalTrials.gov Identifier: NCT02985411.

Nutritional Blood Concentration Biomarkers in the Hispanic Community Health Study/Study of Latinos: Measurement Characteristics and Power

Measurement error is a major issue in self-reported diet that can distort diet-disease relationships. Use of blood concentration biomarkers has the potential to mitigate the subjective bias inherent in self-reporting. As part of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) baseline visit (2008-2011), self-reported information on diet was collected from all participants (n = 16,415). The HCHS/SOL also included annual telephone follow-up, as well as a second (2014-2017) and third (2020-2023) clinic visit. Blood concentration biomarkers for carotenoids, tocopherols, retinol, vitamin B12, and folate were measured in a subset of participants (n = 476) as part of the Study of Latinos: Nutrition and Physical Activity Assessment Study (SOLNAS) (2010-2012). We examined the relationships among biomarker levels, self-reported intake, Hispanic/Latino background (Central American, Cuban, Dominican, Mexican, Puerto Rican, or South American), and other participant characteristics in this diverse cohort. We built regression calibration-based prediction equations for 10 nutritional biomarkers and used a simulation to study the power of detecting a diet-disease association in a multivariable Cox model using a predicted concentration level. Good statistical power was observed for some nutrients with high prediction model R2 values, but further research is needed to understand how best to realize the potential of these dietary biomarkers. This study provides a comprehensive examination of several nutritional biomarkers within the HCHS/SOL, characterizing their associations with subject characteristics and the influence of the measurement characteristics on the power to detect associations with health outcomes.

Racial Differences and Contributory Cardiovascular and Non-Cardiovascular Risk Factors Towards Chronic Kidney Disease Progression

Background

The prevalence of advanced chronic kidney disease (CKD) is higher in Black than in White Americans. We evaluated CKD progression in Black and White participants and the contribution of biological risk factors. We included the study of lung function (measured by forced vital capacity [FVC]), which is part of the emerging notion of interorgan cross-talk with the kidneys to racial differences in CKD progression.

Methods

This longitudinal study included 2175 Black and 2207 White adult Coronary Artery Risk Development in Young Adults (CARDIA) participants. Estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) were measured at study year 10 (age 27-41y) and every five years for 20 years. The outcome was CKD progression through no CKD, low, moderate, high, or very high-risk categories based on eGFR and UACR in combination. The association between race and CKD progression as well as the contribution of risk factors to racial differences were assessed in multivariable-adjusted Cox models.

Results

Black participants had higher CKD transition probabilities than White participants and more prevalent risk factors during the 20-year period studied. Hazard ratios for CKD transition for Black (vs White participants) were 1.38 from No CKD into ≥ low risk, 2.25 from ≤ low risk into ≥ moderate risk, and 4.49 from ≤ moderate risk into ≥ high risk. Racial differences in CKD progression from No CKD into ≥ low risk were primarily explained by FVC (54.8%), hypertension (30.9%), and obesity (20.8%). In contrast, racial differences were less explained in more severe transitions.

Conclusion

Black participants had a higher risk of CKD progression, and this discrepancy may be partly explained by FVC and conventional risk factors.

Associations of dietary, lifestyle, other participant characteristics, and oxidative balance scores with plasma F2-isoprostanes concentrations in a pooled cross-sectional study

PURPOSE

Plasma F₂-isoprostanes (FiP) concentration, a reliably measured, valid, systemic oxidative stress biomarker, has been associated with multiple health-related outcomes; however, associations of most individual dietary and lifestyle exposures with FiP are unclear, and there is no reported oxidative balance score (OBS) comprising multiple dietary and/or lifestyle components weighted by their associations with FiP.

METHODS

To investigate cross-sectional associations of dietary and lifestyle characteristics with plasma FiP concentrations, we used multivariable general linear models to compare adjusted mean FiP concentrations across categories of dietary nutrient and whole-food intakes and lifestyle characteristics in two pooled cross-sectional studies (n = 386). We also developed equal-weight and weighted OBS (nutrient- and foods-based dietary OBS, lifestyle OBS, and total OBS), and compared adjusted mean FiP concentrations across OBS tertiles.

RESULTS

Among men and women combined, adjusted mean FiP concentrations were statistically significantly, proportionately 28.1% higher among those who were obese relative to those who were normal weight; among those in the highest relative to the lowest total nutrient intake tertiles, FiP concentrations were statistically significantly lower by 9.8% for carotenes, 13.6% for lutein/zeaxanthin, 10.9% for vitamin C, 12.2% for vitamin E, 11.5% for glucosinolates, and 5% for calcium. Of the various OBS, the weighted OBS that combined total nutrient intakes and lifestyle exposures was most strongly associated with FiP concentrations: among those in the highest relative to the lowest total OBS, mean FiP concentrations were statistically significantly 29.7% lower (P < 0.001).

CONCLUSION

Multiple dietary and lifestyle characteristics, individually, and especially collectively, may contribute to systemic oxidative stress.

Dietary and plasma carotenoids are positively associated with alpha diversity in the fecal microbiota of pregnant women

Because microbes use carotenoids as an antioxidant for protection, dietary carotenoids could be associated with gut microbiota composition. We aimed to determine associations among reported carotenoid intake, plasma carotenoid concentrations, and fecal bacterial communities in pregnant women. Pregnant women (n = 27) were enrolled in a two-arm study designed to assess feasibility of biospecimen collection and delivery of a practical nutrition intervention. Plasma and fecal samples were collected and women were surveyed with a 24-hr dietary checklist and recalls. Plasma carotenoids were analyzed by HPLC using photodiode array detection. Fecal bacteria were analyzed by 16S rRNA DNA sequencing. Results presented are cross-sectional from the 36-week gestational study visit combined across both study arms due to lack of significant differences between intervention and usual care groups (n = 23 women with complete data). Recent intake of carotenoid-containing foods included carrots, sweet potatoes, mangos, apricots, and/or bell peppers for 48% of women; oranges/orange juice (17%); egg (39%); tomato/tomato-based sauces (52%); fruits (83%); and vegetables (65%). Average plasma carotenoid concentrations were 6.4 µg/dL α-carotene (AC), 17.7 µg/dL β-carotene (BC), 11.4 µg/dL cryptoxanthin, 39.0 µg/dL trans-lycopene, and 29.8 µg/dL zeaxanthin and lutein. AC and BC concentrations were higher in women who recently consumed foods high in carotenoids. CR concentrations were higher in women who consumed oranges/orange juice. Microbiota α-diversity positively correlated with AC and BC. Microbiota β-diversity differed significantly across reported intake of carotenoid containing foods and plasma concentrations of AC. This may reflect an effect of high fiber or improved overall dietary quality, rather than a specific effect of carotenoids. PRACTICAL APPLICATION: Little is known about the association between the gut microbiome and specific dietary microconstituents, such as carotenoids, especially during pregnancy. This research demonstrates that a carotenoid-rich diet during pregnancy supports a diverse microbiota, which could be one mechanism by which carotenoids promote health.

Liquid chromatography as candidate reference method for the determination of vitamins A and E in human serum

BACKGROUND

Owing to the increasing interest in public health research of antioxidant micronutrients and the inaccuracy of routine serum concentrations of the fat-soluble vitamins A (retinol) and E (DL-α-tocopherol) measurements, we developed a reliable, highly sensitive, robust and rapid method for the quantification of two clinically important lipophilic antioxidants in serum using a reverse-phase HPLC/DAD method.

METHOD

Sample preparation and analytical conditions that would affect extraction efficiency and quantitative results of vitamins A and E were investigated and optimized. Vitamins A and E were extracted from serum via liquid-liquid extraction (LLE). After adequate sample preparation, the samples were injected directly into the HPLC system with diode-array detector (DAD). Chromatographic separation was completed in 7 minutes for vitamins A and E. With vitamin A acetate and vitamin E acetate as internal standards, the method was applied to the measurement of vitamins A and E in human serum.

RESULTS

We evaluated method linearity, accuracy (recovery rate and trueness), precision, carryover, limit of quantitation and limit of detection, and measurement uncertainty. The method was evaluated for trueness using NIST Standard Reference Material SRM 968f. The serum concentration of the studied compounds had a good linear relationship in the range of 0.05 ~ 3.0 μg/mL concentration (r ＝ 0.9998), with 0.0077 μg/mL detection limit and 0.025 μg/mL quantitative limit for vitamin A, respectively, and 1.0 ~ 60.0 μg/mL concentration (r ＝ 0.9999), with 0.40 μg/mL detection limit and 0.50 μg/mL quantitative limit for vitamin E, respectively. The intra- and inter-assay coefficients of variation were calculated by using three concentrations (1, 2, and 3) of the studied compounds in human serum samples. Intra-assay and inter-assay precision were 1.23%-4.97% and 0.97%-3.79% for vitamin A, respectively, and 0.64%-4.07% and 0.81%-5.96% for vitamin E, respectively. The average recovery rates were 100.98% for vitamin A, and 99.21% for vitamin E, respectively. The carryover rate of vitamins A and E was below 1%. As for the evaluation of accuracy, the biases were <± 5% by comparing with NIST standard reference material SRM 968f.

CONCLUSION

The method is a simple sample treatment procedure for the determination of fat-soluble vitamins A and E in human serum with high sensitivity and specificity. The proposed method could be recommended as a candidate reference method for the determination of serum concentrations of the fat-soluble vitamins A and E in human serum.

Delineation of the Individual Effects of Vitamin E Isoforms on Early Life Incident Wheezing

OBJECTIVES

To test the hypothesis that maternal plasma alpha-tocopherol levels are associated with protection from childhood wheeze and that this protection is modified by gamma-tocopherol.

STUDY DESIGN

We conducted a prospective nested study in the Infant Susceptibility to Pulmonary Infections and Asthma Following Respiratory Syncytial Virus Exposure birth cohort of 652 children with postpartum maternal plasma vitamin E isoforms used as a surrogate for pregnancy concentrations. Our outcomes were wheezing and recurrent wheezing over a 2-year period, ascertained using validated questionnaires. We assessed the association of alpha- and gamma-tocopherol with wheezing outcomes using multivariable adjusted logistic regression, and tested for interaction between the isoforms with respect to the risk for wheezing outcomes.

RESULTS

Children with wheezing (n = 547, n = 167; 31%) and recurrent wheezing (n = 545, n = 55; 10.1%) over a 2-year period were born to mothers with significantly lower postpartum maternal plasma concentrations of alpha-tocopherol, P = .016 and P = .007, respectively. In analyses of IQR increases, alpha-tocopherol was associated with decreased risk of wheezing (aOR 0.70 [95% CI 0.53,0.92]) and recurrent wheezing (aOR 0.63 [95% CI 0.42,0.95]). For gamma-tocopherol, the aOR for wheezing was 0.79 (95% CI 0.56-1.10) and the aOR for recurrent wheezing was 0.56 (95% CI 0.33-0.94, with nonmonotonic association). The association of alpha-tocopherol with wheezing was modified by gamma-tocopherol (P interaction = .05).

CONCLUSIONS

Increases in postpartum maternal plasma alpha-tocopherol isoform concentrations were associated with decreased likelihood of wheezing over a 2-year period. Gamma-tocopherol modified this association.

Carotenoid Intake and Serum Concentration in Young Finnish Children and Their Relation with Fruit and Vegetable Consumption

Fruit and vegetable intake has been associated with a reduced risk of many chronic diseases. These foods are the main dietary source of carotenoids. The aim of the present study was to evaluate the associations between dietary intake and serum concentrations of α- and β-carotene in a sample of young Finnish children from the population-based birth cohort of the Type 1 Diabetes Prediction and Prevention (DIPP) Study. The current analysis comprised 3-day food records and serum samples from 207 children aged 1, 2 and 3 years. Spearman and partial correlations, as well as a cross-classification analyses, were used to assess the relationship between dietary intake and the corresponding biomarkers. Serum concentrations of α- and β-carotene were significantly higher among the 1-year-old compared to the 3-year-old children. Dietary intakes of α- and β-carotene correlated significantly with their respective serum concentrations in all age groups, the association being highest at the age of 1 year (α-carotene r = 0.48; p < 0.001 and β-carotene r = 0.47; p < 0.001), and lowest at the age of 3 years (α-carotene r = 0.44; p < 0.001 and β-carotene r = 0.30; p < 0.001). A cross-classification showed that 72⁻81% of the participants were correctly classified to the same or adjacent quartile, when comparing the reported dietary intakes and the concentrations of the corresponding carotenoid in serum. The 3-day food record seems to be reasonably valid in the assessment of root vegetable consumption among young Finnish children. Root vegetables were the main dietary source of both carotenoids in all age groups. The high consumption of commercial baby foods among the 1-year-old children was reflected in the relatively high dietary intake and serum concentration of both carotenoids.

Circulating γ-Tocopherol Concentrations Are Inversely Associated with Antioxidant Exposures and Directly Associated with Systemic Oxidative Stress and Inflammation in Adults

Background

Although α- and γ-tocopherol are co-consumed antioxidants, circulating γ-tocopherol concentrations were paradoxically found to be inversely associated with total vitamin E intake and circulating α-tocopherol concentrations. There are limited data on this apparent paradox or on determinants of circulating γ-tocopherol concentrations.

Objective

To help clarify possible determinants of circulating γ-tocopherol concentrations, we investigated associations of circulating γ-tocopherol concentrations with various dietary and lifestyle factors and biomarkers of oxidative stress and inflammation.

Methods

We pooled cross-sectional data from 2 outpatient, adult, elective colonoscopy populations (pooled n = 419) on whom extensive dietary, lifestyle, and medical information was collected, and the following plasma concentrations were measured: α- and γ-tocopherol (via HPLC), F2-isoprostanes (FiPs; via gas chromatography-mass spectrometry), and high-sensitivity C-reactive protein (hsCRP; via latex-enhanced immunonephelometry). Multivariable general linear models were used to assess mean γ-tocopherol differences across quantiles of plasma antioxidant micronutrients, FiPs, and hsCRP; an oxidative balance score [OBS; a composite of anti- and pro-oxidant dietary and lifestyle exposures (a higher score indicates higher antioxidant relative to pro-oxidant exposures)]; and multiple dietary and lifestyle factors.

Results

Adjusted for serum total cholesterol, mean γ-tocopherol concentrations among those in the highest relative to the lowest tertiles of circulating α-tocopherol and β-carotene, the OBS, and total calcium and dietary fiber intakes were 31.0% (P < 0.0001), 29.0% (P < 0.0001), 27.6% (P = 0.0001), 29.7% (P < 0.0001), and 18.6% (P = 0.008) lower, respectively. For those in the highest relative to the lowest tertiles of circulating FiPs and hsCRP, mean γ-tocopherol concentrations were 50% (P < 0.0001) and 39.0% (P < 0.0001) higher, respectively.

Conclusions

These findings support the conclusion that circulating γ-tocopherol concentrations are inversely associated with antioxidant exposures and directly associated with systemic oxidative stress and inflammation in adults. Additional research on possible mechanisms underlying these findings and on whether circulating γ-tocopherol may serve as a biomarker of oxidative stress, inflammation, or both is needed.

Shorter Time to Pregnancy With Increasing Preconception Carotene Concentrations Among Women With 1-2 Previous Pregnancy Losses

Although maternal nutrition may affect fecundity, associations between preconception micronutrient levels and time to pregnancy (TTP) have not been examined. We assessed the relationship between preconception fat-soluble micronutrient concentrations and TTP among women with 1-2 prior pregnancy losses. This was a prospective cohort study of 1,228 women set within the Effects of Aspirin in Gestation and Reproduction (EAGeR) Trial (United States, 2007-2011), which assessed the association of preconception-initiated daily low-dose aspirin with reproductive outcomes. We measured preconception levels of zeaxanthin, cryptoxanthin, lycopene, α- and β-carotene, and α- and γ-tocopherol in serum. We used discrete Cox regression models, accounting for left-truncation and right-censoring, to calculate fecundability odds ratios and 95% confidence intervals. The models adjusted for age, body mass index, race, smoking, alcohol, physical activity, income, vitamin use, cholesterol, treatment arm, and study site. Serum α-carotene levels (per log unit (μg/dL) increase, fecundability odds ratio (FOR) = 1.17, 95% confidence interval (CI): 1.00, 1.36) and serum α-carotene concentrations at or above the US average (2.92 μg/dL) versus below the average (FOR = 1.21, 95% CI: 1.02, 1.44) were associated with shorter TTP. Compared with levels below the US average (187 μg/dL), γ-tocopherol concentrations at or above the average were associated with longer TTP (FOR = 0.83, 95% CI: 0.69, 1.00). The potential for these nutrients to influence fecundability deserves further exploration.

Simple and sensitive dilute-and-shoot analysis of carotenoids in human plasma

Carotenoids in human plasma are used as biomarkers of vegetable and fruit intake. Large sample volumes and intensive sample processing make measurement of these species cumbersome. We developed a dilute-and-shoot method for the quantitation of α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin using 10 μL of plasma. Plasma was injected into methanol containing internal standard and deproteinized by centrifugation. The carotenoids in the supernatant were separated using a YMC C-30 column and quantified by tandem mass spectrometry. The linearity for carotenoids ranged from sub-fmol to approximately 300 fmol on-column. Spike recovery experiments were used to correct for matrix effects. The method was validated using the human plasma standard NIST SRM 968e. Over 400 sample analyses were performed using the same guard and analytical columns. This method represents an improvement over current techniques because of the small sample size needed, ease of sample preparation, and improvement in the determination of carotenoid content.

Biomarkers of carotenoid bioavailability

The use of biomarkers constitutes an essential tool to assess the bioavailability of carotenoids in humans. The present article aims to review several methodological, host-related and modulating factors relevant on assessing and interpreting carotenoid bioavailability. Markers for carotenoid bioavailability can be broadly divided into direct, biochemical or "analytical" markers and indirect, physiological or "functional" indicators. Analytical markers usually refer to biochemical indicators of intake and/or status (short and long term exposure) while functional measures may be interpreted in terms of cumulative exposure, biological effect (bioactivity) or modification of risk factors. Both types of markers display advantages and limitations but, in general, a relationship exists among the type of marker, the biological specimen needed and the time required for a change. Humans may absorb a wide range of carotenes and xanthophylls and many of them may be found in serum and tissues. However, under physiological conditions, the several classes of dietary carotenoids may behave unequally leading to a different systemic profile and, moreover, they can be selectively accumulated at target tissues. In addition, some carotenoids may be chemically and enzymatically modified generating different oxidative metabolites and apocarotenoids. Quantitatively, the biological response upon carotenoid intervention (assessed by analytical and functional markers) is highly variable but the use of large doses and long-term protocols may lead to saturation effects and the loss of linearity in the response. Also, despite carotenoid exposition is considered to be safe, markers of overexposure include clinical signs (i.e. carotenodermia, corneal rings and retinopathy) and biochemical indicators (hypercarotenemia, xanthophyll esters). Overall, both host-related and methodological factors may influence analytical and functional markers to assess carotenoid bioavailability although the different subclasses of carotenoids may not be equally affected.

Design of microemulsion system suitable for the oral delivery of poorly aqueous soluble beta-carotene

Beta-carotene is a potent antioxidant for maintaining human health. However, its oral absorption is low due to poor aqueous solubility of less than 1 μg/ml. A microemulsion delivery system was designed to solubilize beta-carotene toward enhancing its oral bioavailability. From seven pseudoternary diagrams constructed, three systems were selected with large microemulsion areas suitable for oral administration and dilution in the predominately aqueous gastrointestinal fluids. Conductivity and rheology characterization were conducted along four dilution lines within the selected systems. Three pseudoternary-phase diagrams were selected with large microemulsion regions, >60% of the total phase diagram area, which provide microemulsions with higher drug-loading capacity. A phenomenon was observed by which both propylene glycol and Capmul MCM EP stabilize the microstructure of the microemulsions has been proposed based on the characterization studies. An optimal bicontinuous microemulsion formulation was selected comprising 12% orange oil, 24% Capmul MCM, 18% Tween 20, 6% Labrasol, 20% propylene glycol and 20% water, with a high beta-carotene loading capacity of 140.8 μg/ml and droplet size of 117.4 nm. In conclusion, the developed novel microemulsion formulation allows solubilizing beta-carotene and is a promising basis for further development as a functional beverage.

Antioxidant status in a group of institutionalised elderly people with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is one of the most important and prevalent diseases suffered by the elderly. Evidence exists that its onset and severity might be conditioned by antioxidant status. The aim of the present study was to investigate the relationship between antioxidant status and COPD in institutionalised elderly people. In all, 183 elderly people aged >65 years (twenty-one had COPD and 160 healthy controls) were studied. The subjects' diets were investigated via the use of precise individual weighing for 7 d. Body weight, height, and biceps and triceps skinfold thickness were measured, and body fat (kg) and BMI (kg/m2) were calculated. Serum retinol, α-tocopherol, β-carotene and vitamin C levels were determined. Subjects with COPD ate less fruits than healthy controls (117 (sd 52) v. 192 (sd 161) g/d), their coverage of the recommended intake of vitamin C was smaller (150 (sd 45) v. 191 (sd 88) %; note that both exceeded 100 %) and their diets had a lower antioxidant capacity (6558 (sd 2381) v. 9328 (sd 5367) mmol trolox equivalent/d). Those with COPD had lower serum vitamin C and α-tocopherol concentrations than healthy controls (32·4 (sd 15·3) v. 41·5 (sd 14·8) µmol/l and 12·1 (sd 3·2) v. 13·9 (sd 2·8) µmol/l, respectively). In addition, subjects with α-tocopherol <14·1µmol/l (50th percentile) were at 6·43 times greater risk of having COPD than those subjects with ≥14·1µmol/l (OR 6·43; 95 % CI 1·17, 35·24; P<0·05), taking sex, age, use of tobacco, body fat and vitamin E intake as covariables. Subjects with COPD had diets of poorer antioxidant quality, especially with respect to vitamins C and E, compared with healthy controls.

Oxidative stress, anti-oxidants and the cross-sectional and longitudinal association with depressive symptoms: results from the CARDIA study

Depression may be accompanied by increased oxidative stress and decreased circulating anti-oxidants. This study examines the association between depressive symptoms, F2-isoprostanes and carotenoids in a US community sample. The study includes 3009 participants (mean age 40.3, 54.2% female) from CARDIA (Coronary Artery Risk Development in Young Adults). Cross-sectional analyses were performed on data from the year 15 examination (2000-2001) including subjects whose depressive symptoms were assessed with the Center for Epidemiologic Studies Depression Scale (CES-D) and had measurements of plasma F2-isoprostanes (gas chromatography/mass spectrometry) or serum carotenoids (high-performance liquid chromatography). Carotenoids zeaxanthin/lutein, β-cryptoxanthin, lycopene, α-carotene, β-carotene were standardized and summed. Longitudinal analyses were conducted using the data from other examinations at 5-year intervals. Cross-lagged analyses investigated whether CES-D predicted F2-isoprostanes or carotenoids at the following exam, and vice versa. Regression analyses were controlled for sociodemographics, health and lifestyle factors. F2-isoprostanes were higher in subjects with depressive symptoms (CES-D ⩾ 16) after adjustment for sociodemographics (55.7 vs 52.0 pg ml(-1); Cohen's d = 0.14, P < 0.001). There was no difference in F2-isoprostanes after further adjustment for health and lifestyle factors. Carotenoids were lower in those with CES-D scores ⩾ 16, even after adjustment for health and lifestyle factors (standardized sum 238.7 vs 244.0, Cohen's d = -0.16, P < 0.001). Longitudinal analyses confirmed that depression predicts subsequent F2-isoprostane and carotenoid levels. Neither F2-isoprostanes nor carotenoids predicted subsequent depression. In conclusion, depressive symptoms were cross-sectionally and longitudinally associated with increased F2-isoprostanes and decreased carotenoids. The association with F2-isoprostanes can largely be explained by lifestyle factors, but lower carotenoids were independently associated with depressive symptoms.

Oxidative stress, oxidative balance score, and hypertension among a racially diverse population

Hypertension is a risk factor for several vascular diseases. Evidence suggests that oxidative stress (OS) plays a significant role in its pathophysiology. Human studies have shown inconsistent results, varying based on the OS biomarker and study population. In a racially diverse population, examine the association between: (1) blood pressure or hypertension and four markers of OS and (2) blood pressure or hypertension and oxidative balance score (OBS). Using data (n = 317) from the cross-sectional study on race, stress, and hypertension, an OBS was constructed from various measures of pro-oxidant and antioxidant exposures. OS was assessed by four biomarkers: fluorescence oxidative products, F2-isoprostanes, mitochondrial DNA copy number, and gamma tocopherol. Multivariate linear and logistic regression analyses were used to estimate the associations of interest. None of the adjusted associations between hypertension and OS markers was statistically significant. OBS was inversely associated with hypertension after adjusting for study covariates. Persons with higher OBS have lower odds of having hypertension; however, the evidence on the relationship between OS markers and blood pressure remains unconvincing.

New risk factors for adult-onset incident asthma. A nested case-control study of host antioxidant defense

RATIONALE

Host antioxidant defense, consisting of enzymatic antioxidant activity and nonenzymatic antioxidant micronutrients, is implicated in asthma pathogenesis. Studies of antioxidant defense and adult incident asthma have either used measures of antioxidants estimated from questionnaires or not considered enzymatic aspects of host defense.

OBJECTIVES

We conducted the first study designed and powered to investigate the association of antioxidant defenses on adult incident asthma.

METHODS

In a nested case-control study, we followed Shanghai women (aged 40-70 years) without prevalent asthma at baseline, over 8 years. Subjects with incident asthma were ascertained prospectively by gold standard testing of symptomatic women and matched to two asymptomatic control subjects.

MEASUREMENTS AND MAIN RESULTS

Baseline urinary F2-isoprostanes, plasma concentrations of antioxidant micronutrients (tocopherols, xanthines, carotenes, and lycopene), and antioxidant enzyme activity (platelet-activating factor acetylhydrolase [PAF-AH] and superoxide dismutase) were measured from samples collected before disease onset. Among 65,372 women, 150 (0.24%) developed asthma. F2-isoprostane levels before asthma onset were not different between cases and control subjects. Doubling of α-tocopherol concentrations and PAF-AH activity was associated with 50 and 37% decreased risk of incident asthma (α-tocopherol: adjusted odds ratio = 0.52; 95% confidence interval, 0.32-0.84; PAF-AH: adjusted odds ratio = 0.63; 95% confidence interval, 0.42-0.93).

CONCLUSIONS

In this prospective study, α-tocopherol, within normal reference ranges, and PAF-AH enzymatic activity were associated with decreased asthma development. These modifiable risk factors may be an effective strategy to test for primary asthma prevention.

Oxidative balance score and oxidative stress biomarkers in a study of Whites, African Americans, and African immigrants

CONTEXT

Oxidative balance score (OBS) is a composite measure of multiple pro- and antioxidant exposures.

OBJECTIVE

To investigate associations of OBS with F2-isoprostanes (FIP), mitochondrial DNA copy number (mtDNA), and fluorescent oxidative products (FOP), and assess inter-relationships among the biomarkers.

METHODS

In a cross-sectional study, associations of a thirteen-component OBS with biomarker levels were assessed using multivariable regression models.

RESULTS

Association of OBS with FIP, but not with FOP, was in the hypothesized direction. The results for mtDNA were unstable and analysis-dependent. The three biomarkers were not inter-correlated.

CONCLUSIONS

Different biomarkers of oxidative stress may reflect different biological processes.

The vitamin E isoforms α-tocopherol and γ-tocopherol have opposite associations with spirometric parameters: the CARDIA study

Background

Clinical studies of the associations of vitamin E with lung function have reported conflicting results. However, these reports primarily examine the α-tocopherol isoform of vitamin E and have not included the isoform γ-tocopherol which we recently demonstrated in vitro opposes the function of α-tocopherol. We previously demonstrated, in vitro and in animal studies, that the vitamin E isoform α-tocopherol protects, but the isoform γ-tocopherol promotes lung inflammation and airway hyperresponsiveness.

Methods

To translate these findings to humans, we conducted analysis of 4526 adults in the Coronary Artery Risk Development in Young Adults (CARDIA) multi-center cohort with available spirometry and tocopherol data in blacks and whites. Spirometry was obtained at years 0, 5, 10, and 20 and serum tocopherol was from years 0, 7 and 15 of CARDIA.

Results

In cross-sectional regression analysis at year 0, higher γ-tocopherol associated with lower FEV₁ (p = 0.03 in blacks and p = 0.01 in all participants) and FVC (p = 0.01 in blacks, p = 0.05 in whites, and p = 0.005 in all participants), whereas higher α-tocopherol associated with higher FVC (p = 0.04 in blacks and whites and p = 0.01 in all participants). In the lowest quartile of α-tocopherol, higher γ-tocopherol associated with a lower FEV₁ (p = 0.05 in blacks and p = 0.02 in all participants). In contrast, in the lowest quartile of γ-tocopherol, higher α-tocopherol associated with a higher FEV₁ (p = 0.03) in blacks. Serum γ-tocopherol >10 μM was associated with a 175–545 ml lower FEV₁ and FVC at ages 21–55 years.

Conclusion

Increasing serum concentrations of γ-tocopherol were associated with lower FEV1 or FVC, whereas increasing serum concentrations of α-tocopherol was associated with higher FEV1 or FVC. Based on the prevalence of serum γ-tocopherol >10 μM in adults in CARDIA and the adult U.S. population in the 2011 census, we expect that the lower FEV₁ and FVC at these concentrations of serum γ-tocopherol occur in up to 4.5 million adults in the population.

Oxidative balance score, colorectal adenoma, and markers of oxidative stress and inflammation

BACKGROUND

An oxidative balance score (OBS) that combines pro- and antioxidant exposures was previously reported to be associated with incident sporadic colorectal adenoma. We extend the previous analyses by assessing associations of the OBS and colorectal adenoma with circulating biomarkers of oxidative stress [F2-isoprostanes (FIP) and fluorescent oxidation products (FOP)], and inflammation [C-reactive protein (CRP)].

METHODS

Using pooled data from two previously conducted colonoscopy-based case-control studies of incident, sporadic colorectal adenoma (n = 365), the OBS was constructed and divided into three approximately equal intervals, with the lowest interval used as the reference. Biomarker levels were dichotomized as "high" versus "low" based on the median values among controls. Multivariable logistic regression was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

For the OBS-adenoma association, the ORs (95% CIs) for the middle and highest (relative to the lowest) score intervals were 0.81 (0.46-1.43) and 0.39 (0.17-0.89), respectively. The corresponding OBS category-specific ORs (95% CIs) were 0.50 (0.25-1.01) and 0.25 (0.10-0.65) for FIP, 2.01 (1.13-3.75) and 3.48 (1.51-8.02) for FOP, and 0.57 (0.31-1.04) and 0.21 (0.09-0.49) for CRP. The ORs (95% CIs) reflecting associations of adenoma with high levels of FIP, FOP, and CRP were 1.89 (1.08-3.30), 1.82 (1.11-2.99), and 1.45 (0.88-2.40), respectively.

CONCLUSIONS

As hypothesized, the OBS was inversely associated with colorectal adenoma and circulating FIP and CRP levels. The reason for the unexpected direct OBS-FOP association is unknown.

IMPACT

These data support the use of combined measures of pro- and antioxidant exposures in studies of colorectal neoplasia.

In vitro investigation of the bioaccessibility of carotenoids from raw, frozen and boiled red chili peppers (Capsicum annuum)

BACKGROUND

Carotenoid-rich foods are associated with antioxidant activity and the ability to alleviate chronic diseases.

PURPOSE

The present study investigated the effect of processing on the content and bioaccessibility of carotenoids from 13 cultivars of red chili pepper (Capsicum annuum).

METHODS

Carotenoids in chili peppers were analyzed before an in vitro digestion process. The portion of carotenoid transferred to the micelle fraction (bioaccessibility) was also quantified.

RESULTS

β-Carotene, β-cryptoxanthin, capsanthin and antheraxanthin were the most abundant carotenoids. Zeaxanthin, violaxanthin, neoxanthin and lutein were detected at lower concentrations. In general, freezing and boiling reduced carotenoid contents. Capsanthin and zeaxanthin had the highest bioaccessibility at an average value from 36 to 40%, followed by antheraxanthin (26%). Bioaccessibility of β-cryptoxanthin, violaxanthin and β-carotene was lower, averaging 6.1, 4.8 and 4.0%, respectively. Neoxanthin and lutein were not detected in micelles. Freezing increased the bioaccessibility of capsanthin, zeaxanthin, antheraxanthin, β-cryptoxanthin and violaxanthin; β-cryptoxanthin bioaccessibility increased and capsanthin and zeaxanthin bioaccessibility decreased following boiling.

CONCLUSIONS

Differences in the contents and bioaccessibility of carotenoids in 13 C. annuum cultivars and between the processed methods were herein evidenced.

Inverse associations between serum concentrations of zeaxanthin and other carotenoids and colorectal neoplasm in Japanese

BACKGROUND

To investigate the associations between serum concentrations of carotenoids and the presence of colorectal polyps and cancers in Japanese using a cross-sectional study.

METHODS

893 subjects who underwent colorectal endoscopy between 2001 and 2002 provided serum samples and information on lifestyle factors. Serum concentrations of six carotenoids were compared among patients with polyps, cancers, and controls.

RESULTS

In males, high serum zeaxanthin was associated with decreased rates of polyps [odds ratio (OR) = 0.48, 95 % confidence interval (CI) 0.27-0.87] and cancer (OR = 0.35, 95 % CI 0.12-1.06), adjusting for age, body mass index, serum cholesterol, smoking status, and alcohol intake. In females, zeaxanthin (OR = 0.25, 95 % CI 0.07-0.82), lutein (OR = 0.30, 95 % CI 0.10-0.94), alpha-carotene (OR = 0.30, 95 % CI 0.10-0.90), and beta-carotene (OR = 0.27, 95 % CI 0.09-0.85) showed significant inverse associations with cancer development. These associations were consistent with findings of inverse associations between the ingestion of green-yellow vegetables (OR = 0.44, 95 % CI 0.23-0.84), carrots and pumpkins (OR = 0.46, 95 % CI 0.25-0.86), and fruits (OR = 0.53, 95 % CI 0.30-0.94) and polyp in males, and between carrots and pumpkins (OR = 0.30, 95 % CI 0.09-0.99), legumes (OR = 0.14, 95 % CI 0.04-0.44), and seaweed (OR = 0.23, 95 % CI 0.07-0.75) and cancer development in females.

CONCLUSIONS

These results provide further support for the protective effects of carotenoids contained in green-yellow vegetables and fruits against colorectal neoplasm in Japanese.

Effects of lycopene on the initial state of atherosclerosis in New Zealand White (NZW) rabbits

Background

Lycopene is the main carotenoid in tomatoes, where it is found in high concentrations. Strong epidemiological evidence suggests that lycopene may provide protection against cardiovascular diseases. We therefore studied the effects of lycopene on diet-induced increase in serum lipid levels and the initiation of atherosclerosis in New Zealand White (NZW) rabbits.

Methodology/Principal Findings

The animals, divided into four groups of 9 animals each, were fed either a standard diet, a high-cholesterol diet containing 0.5% cholesterol, a high-cholesterol diet containing placebo beadlets, or a high-cholesterol diet plus 5 mg/kg body weight/day of lycopene (in the form of lycopene beadlets), for a period of 4 weeks. We found significantly elevated lycopene plasma levels in the animal group treated with lycopene beadlets. Compared to the high-cholesterol and the placebo group, this was associated with a significant reduction of 50% in total cholesterol and LDL cholesterol serum levels in the lycopene group. The amount of cholesteryl ester in the aorta was significantly decreased by lycopene. However, we did not observe a significant decrease in the extent of aortic surface lipid accumulation in the lycopene group. In addition, no differences in the intima-media thickness among groups were observed. Endothelial-dependent and endothelial-independent vasodilation in isolated rabbit aortic and carotid rings did not differ among any of the animal groups.

Conclusions

Lycopene supplementation for 4 weeks increased lycopene plasma levels in the animals. Although we found strongly reduced total and LDL cholesterol serum levels as well as significantly lower amounts of cholesteryl ester in the aortae in the lycopene-treated group, no significant differences in initial lesions in the aortae were detected.

Lack of effects of tomato products on endothelial function in human subjects: results of a randomised, placebo-controlled cross-over study

Epidemiological studies suggest that consumption of tomato products reduces the risk of CVD via antioxidant, hypocholesterolaemic and anti-inflammatory mechanisms. Although experimental data also describe beneficial effects on endothelial function, clinical data in human subjects are lacking. To test the hypothesis that tomato ingestion ameliorates endothelial function, we randomised healthy non-smoking postmenopausal women to consume a buttered roll with and without tomato purée (70 g) in a cross-over design. Endothelial-dependent flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation of the brachial artery were assessed with high-resolution ultrasound (13 MHz linear array transducer). Acute (24 h) and long-term (7 d) effects were examined after daily consumption of the described meal. Nineteen volunteers completed the protocol and provided technically suitable ultrasound measurement data. Plasma lycopene levels increased from 0·30 (sem0·04) (baseline) to 0·42 (sem0·04) and to 0·74 (sem0·06) μmafter 24 h and 7 d, respectively, with tomato purée consumption. These data indicated an effective absorption of the tomato product. However, both acute and long-term tomato purée consumption had no effects on endothelium-dependent or -independent dilation of the brachial artery. In addition, we found no correlation between lycopene plasma levels and FMD. In conclusion, consumption of tomato products associated with a significant increase in plasma lycopene levels had no effects on endothelial function in healthy postmenopausal women.

{beta}-Apocarotenoids do not significantly activate retinoic acid receptors {alpha} or {beta}

beta-Carotene oxygenase 2 cleaves beta-carotene asymmetrically at non-central double bonds of the polyene chain, yielding apocarotenal molecules. The hypothesis tested was that apocarotenoids are able to stimulate transcription by activating retinoic acid receptors (RARs). The effects of long- and short-chain apocarotenals and apocarotenoic acids on the activation of RARalpha and RARbeta transfected into monkey kidney fibroblast cells (CV-1) were investigated. We synthesized or purified beta-apo-8'-carotenoic acid (apo-8'-CA), beta-apo-14'-carotenoic acid (apo-14'-CA), beta-cyclocitral (BCL), beta-cyclogernanic acid (BCA), beta-ionone (BI), beta-ionylideneacetaldehyde (BIA) beta-ionylideneacetic acid (BIAA) and a C13 ketone, beta-apo-13-carotenone (C13). None of the apocarotenoids tested showed significant transactivation activity for the RARs when compared with all-trans retinoic acid (RA). The results suggest that biological effects of these apocarotenoids are through mechanisms other than activation of RARalpha and beta.

Biochemical validation of food frequency questionnaire-estimated carotenoid, alpha-tocopherol, and folate intakes among African Americans and non-Hispanic Whites in the Southern Community Cohort Study

Few food frequency questionnaires (FFQs) have been developed specifically for use among African Americans, and reports of FFQ performance among African Americans or low-income groups assessed using biochemical indicators are scarce. The authors conducted a validation study within the Southern Community Cohort Study to evaluate FFQ-estimated intakes of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, folate, and alpha-tocopherol in relation to blood levels of these nutrients. Included were 255 nonsmoking participants (125 African Americans, 130 non-Hispanic whites) who provided a blood sample at the time of study enrollment and FFQ administration in 2002-2004. Levels of biochemical indicators of each micronutrient (alpha-tocopherol among women only) significantly increased with increasing FFQ-estimated intake (adjusted correlation coefficients: alpha-carotene, 0.35; beta-carotene, 0.28; beta-cryptoxanthin, 0.35; lutein/zeaxanthin, 0.28; lycopene, 0.15; folate, 0.26; alpha-tocopherol, 0.26 among women; all P's < 0.05). Subjects in the top decile of FFQ intake had blood levels that were 27% (lycopene) to 178% (beta-cryptoxanthin) higher than those of subjects in the lowest decile. Satisfactory FFQ performance was noted even for participants with less than a high school education. Some variation was noted in the FFQ's ability to predict blood levels for subgroups defined by race, sex, and other characteristics, but overall the Southern Community Cohort Study FFQ appears to generate useful dietary exposure rankings in the cohort.

Synergistic interaction of cigarette smoking and alcohol drinking with serum carotenoid concentrations: findings from a middle-aged Japanese population

Previous studies have indicated low serum carotenoid concentrations among cigarette smokers and/or alcohol drinkers, but little is known about the interaction of smoking and drinking with serum carotenoids. We tested the hypothesis that smoking and drinking reduce serum carotenoid concentrations synergistically. A total of 1073 subjects (357 male and 716 female) who had received health examinations in the town of Mikkabi, Shizuoka Prefecture, Japan, participated in the study. The subjects were divided into six groups according to alcohol intake (non-drinkers, < 1 g/d; light drinkers, > or = 1, < 25 g/d; moderate-to-heavy drinkers, > or = 25 g/d) and smoking status (non-smokers and current smokers). The dietary intakes and serum concentrations of six carotenoids (lycopene, alpha-carotene, beta-carotene, lutein, beta-cryptoxanthin and zeaxanthin) within each group were evaluated cross-sectionally. The dietary intakes of all carotenoids did not differ in the six groups after adjusting for age and sex. The multivariate-adjusted means of the serum carotenoid concentrations in non-drinkers did not differ between non-smokers and current smokers. In contrast, the adjusted means of serum alpha-carotene, beta-carotene and beta-cryptoxanthin were significantly lower than those with increased alcohol intake, and these lower serum carotenoids among alcohol drinkers were more evident in current smokers than in non-smokers. Serum lycopene of moderate-to-heavy drinkers was significantly lower than that of non-drinkers, but it was not influenced by smoking. Neither smoking nor drinking was associated with the serum concentrations of lutein and zeaxanthin. These results suggest that smoking and drinking may reduce the serum alpha-carotene, beta-carotene and beta-cryptoxanthin concentrations in a synergistic manner.

Circulating carotenoid concentrations and incident hypertension: the Coronary Artery Risk Development in Young Adults (CARDIA) study

BACKGROUND

Several epidemiological studies have demonstrated that carotenoid concentrations relate inversely to cardiovascular disease incidence. Thus, we examined the association of circulating carotenoids with hypertension, a major macrovascular disease risk factor.

METHODS

Black and White men and women in the Coronary Artery Risk Development in Young Adults Study, aged 18-30 years at recruitment (1985-1986) from four US cities, were investigated over 20 years. At years 0, 7, and 15, we determined the relationships of the sum of four serum carotenoids (alpha-carotene, beta-carotene, lutein/zeaxanthin, cryptoxanthin) and of lycopene with incident hypertension using proportional hazards regression models.

RESULTS

In 4412 participants, year 0 sum of four carotenoids was significantly inversely associated with 20-year hypertension incidence after adjustment for baseline systolic blood pressure and other confounding factors (relative hazard per SD increase of sum of four carotenoids: 0.91; 95% confidence interval = 0.84-0.99). The inverse relationships persisted in time-dependent models updating year 0 sum of four carotenoids with year 7 and year 15 values (relative hazard per SD increase of sum of four carotenoids: 0.84; 95% confidence interval = 0.77-0.92). Lycopene was unrelated to hypertension in any model.

CONCLUSION

Those individuals with higher concentrations of sum of carotenoids, not including lycopene, generally had lower risk for future hypertension.

Tomato juice decreases LDL cholesterol levels and increases LDL resistance to oxidation

High dietary intakes of tomato products are often associated with a reduced risk of CVD, but the atheroprotective mechanisms have not been established. This study was conducted to investigate the effects of increased dietary intake of tomato products on plasma lipids and LDL oxidation. The diet intervention included a baseline period, a 3-week low tomato diet (no tomato products allowed) and a 3-week high tomato diet (400 ml tomato juice and 30 mg tomato ketchup daily). Twenty-one healthy study subjects participated in the study. Total cholesterol concentration was reduced by 5·9 (sd10) % (P = 0·002) and LDL cholesterol concentration by 12·9 (sd17·0) % (P = 0·0002) with the high tomato diet compared to the low tomato diet. The changes in total and LDL cholesterol concentrations correlated significantly with the changes in serum lycopene (r0·56,P = 0·009;r0·60,P = 0·004, total and LDL, respectively), β-carotene (r0·58,P = 0·005;r0·70,P < 0·001) and γ-carotene concentrations (r0·64,P = 0·002;r0·64,P = 0·002). The level of circulating LDL to resist formation of oxidized phospholipids increased 13 % (P = 0·02) in response to the high tomato diet. In conclusion, a high dietary intake of tomato products had atheroprotective effects, it significantly reduced LDL cholesterol levels, and increased LDL resistance to oxidation in healthy normocholesterolaemic adults. These atheroprotective features associated with changes in serum lycopene, β-carotene and γ-carotene levels.

Main Outcomes of the FRESH START Trial: A Sequentially Tailored, Diet and Exercise Mailed Print Intervention Among Breast and Prostate Cancer Survivors

Purpose

Cancer survivors are at increased risk for cardiovascular disease, diabetes, osteoporosis, and second primary tumors. Healthful lifestyle practices may improve the health and well-being of survivors. The FRESH START trial tested the efficacy of sequentially tailored versus standardized mailed materials on improving cancer survivors’ diet and exercise behaviors.

Methods

Five hundred forty-three individuals with newly diagnosed locoregional breast or prostate cancer were recruited from 39 states and two provinces within North America. Participants were randomly assigned either to a 10-month program of tailored mailed print materials promoting fruit and vegetable (F&V) consumption, reducing total/saturated fat intake, and/or increasing exercise or to a 10-month program of nontailored mailed materials on diet and exercise available in the public domain. Telephone surveys conducted at baseline and 1 year assessed body mass index (BMI), dietary consumption, physical activity, and other psychosocial/behavioral indices. Clinical assessments were conducted on a 23% subsample; information was used to validate self-reports.

Results

Five hundred nineteen participants completed the 1-year follow-up (4.4% attrition; sample characteristics: 57 ± 10.8 years old, 83% white, 56% female, 64% overweight/obese, and 0% underweight). Although both arms significantly improved their lifestyle behaviors (P < .05), significantly greater gains occurred in the FRESH START intervention versus the control arm (practice of two or more goal behaviors: +34% v +18%, P < .0001; exercise minutes per week: +59.3 v +39.2 minutes, P = .02; F&V per day: +1.1 v +0.6 servings, P = .01; total fat: −4.4% v –2.1%, P < .0001; saturated fat: −1.3% v –0.3%, P < .0001; and BMI: −0.3 v +0.1 kg/m2, respectively, P = .004).

Conclusion

Mailed material interventions, especially those that are tailored, are effective in promoting healthful lifestyle changes among cancer survivors. Further study is needed to determine sustainability, cost to benefit, and generalizability to other cancer populations.

Effects of ingestion of tomatoes, tomato juice and tomato purée on contents of lycopene isomers, tocopherols and ascorbic acid in human plasma as well as on lycopene isomer pattern

Tomatoes are an important part of the diet. Lycopene, the predominant carotenoid in tomatoes, is hypothesised to mainly mediate the health benefits of tomato products. Anticancer activity of tomato products and lycopene has been suggested by numerous studies. The aim of the present study was to investigate the effect of ingestion of three different tomato-based foodstuffs on plasma contents of lycopene, tocopherols and ascorbic acid. Because isomers of lycopene may have different biological activities, a special interest was to look how the lycopene isomer pattern is changed depending on the matrix of tomato products. Following a 2-week depletion phase volunteers ingested 12·5mg lycopene/d for 4 weeks comprising tomatoes, tomato juice or tomato purée. The basal levels of lycopene in plasma were comparable for all groups and decreased significantly during the 2 weeks of depletion to approximately half of the basal values. Following intervention, plasma lycopene concentration increased significantly. Conversely, supplementation did not significantly affect levels of tocopherols and ascorbic acid in plasma. Regarding isomers of lycopene, the (Z)-lycopene:(all-E)-lycopene plasma isomer ratio was significantly changed during the study for all groups. A remarkable enrichment of the relative contents of (5Z)-lycopene was observed during the depletion period, which supports the hypothesis that lycopene (Z)-isomers are formed within the human body after ingestion of (all-E)-lycopene. After dietary intervention with lycopene-rich products the isomer ratios returned to those observed at the start of the study. Further investigations will clarify the process of isomerisation in more detail.

Validation of a Brief Dietary Assessment to Guide Counseling for Cardiovascular Disease Risk Reduction in an Underserved Population

BACKGROUND

Brief dietary assessment tools are needed to guide counseling in underserved populations to reduce cardiovascular disease (CVD) risk. The Dietary Risk Assessment is one such tool modified over time to reflect emerging evidence concerning diet and CVD risk.

OBJECTIVE

To examine the capacity of the modified Dietary Risk Assessment tool to measure aspects of diet quality in a sample of underserved, midlife (aged 40 to 64 years) women, by comparing Dietary Risk Assessment results to those of a longer food frequency questionnaire (FFQ) and with serum carotenoids.

DESIGN

This study used baseline data from women enrolled in a CVD risk reduction intervention trial. The Dietary Risk Assessment was administered to 236 women and results were compared to those from a longer FFQ administered to 104 women, and to serum carotenoids results from all participants.

RESULTS

Correlations between Dietary Risk Assessment indexes and corresponding measures from the FFQ were statistically significant: fruit and vegetable, r=-0.53 (P<0.0001, correlation is negative as a lower Dietary Risk Assessment score indicates greater fruit and vegetable intake); saturated fat, r=0.60 (P<0.0001). In linear regression models stratified by smoking and adjusted for body mass index, low-density lipoprotein cholesterol level, high-density lipoprotein cholesterol level, very-low-density lipoprotein cholesterol level, and age, the Dietary Risk Assessment fruit and vegetable index was significantly associated with serum carotenoids (parameter estimate for nonsmokers -0.22, P=0.01; smokers -0.45, P=0.003). Correlation coefficients between Dietary Risk Assessment total score and three diet quality index scores derived from FFQ variables were statistically significant, ranging in magnitude from 0.57 to 0.60.

CONCLUSIONS

The modified Dietary Risk Assessment provides a reasonable assessment of dietary factors associated with CVD risk; thus, it is appropriate for use to guide dietary counseling in CVD prevention programs for underserved, midlife, women.

Relationships of circulating carotenoid concentrations with several markers of inflammation, oxidative stress, and endothelial dysfunction: the Coronary Artery Risk Development in Young Adults (CARDIA)/Young Adult Longitudinal Trends in Antioxidants (YALTA) study

BACKGROUND

Serum carotenoid concentrations relate inversely to cardiovascular disease incidence. To clarify the effect of carotenoids on atherosclerotic risk factors, we examined the association of circulating carotenoids with inflammation, oxidative stress, endothelial dysfunction, and smoking.

METHODS

Black and white men and women in the Coronary Artery Risk Development in Young Adults study, ages 18 to 30 years at recruitment (1985-1986) from 4 US cities, were investigated over 15 years. We included 2048 to 4580 participants in analyses of the sum of serum alpha-carotene, beta-carotene, zeaxanthin/lutein, and beta-cryptoxanthin concentrations and of lycopene at year 0 and at year 7.

RESULTS

The year 0 sum of 4 carotenoids was inversely associated (all P <0.05) with year 0 leukocyte count (slope per sum carotenoid SD, -0.17); year 7 fibrinogen (slope, -0.10); year 7 and year 15 C-reactive protein (slope, -0.12 and -0.09); and year 15 F(2)-isoprostanes (slope, -13.0), soluble P-selectin (slope, -0.48), and soluble intercellular adhesion molecule-1 (sICAM1; slope, -5.1). Leukocyte counts and sICAM1 and F(2)-isoprostane concentrations had stronger associations in smokers than in nonsmokers, and sICAM1 concentrations were higher in the highest carotenoid quartile in smokers than in the lowest carotenoid quartile in nonsmokers. Superoxide dismutase was positively associated with the sum of 4 carotenoids (slope, 0.12; P <0.01). Lycopene was inversely associated only with sICAM1. The year 7 carotenoid associations with these markers were mostly similar to those at year 0.

CONCLUSIONS

Circulating serum carotenoids were associated, some interactively with smoking, in apparently beneficial directions with markers of inflammation, oxidative stress, and endothelial dysfunction.

Effect of exercise training on in vitro LDL oxidation and free radical-induced hemolysis: the HERITAGE Family Study

Oxidant stress and overproduction of reactive oxygen species (ROS) contribute to the development of cardiovascular disease. Oxidative modifications of low-density lipoproteins (LDL) are thought to play an early and critical role in atherogenesis. LDL oxidation can be reproduced in vitro, but results usually show a large interindividual variation not entirely explained by the environment. Free radical-induced hemolysis is also proposed to reveal the overall antioxidant capacity. The roles of genetic factors and exercise on the variability of both measures were investigated. The study was conducted in 146 healthy individuals from 28 families participating in a 20-week exercise-training program. In addition to important biological and environmental influences on variation, significant familial aggregation was detected in all oxidation measures. Exercise did not significantly modify the LDL oxidation parameters, but significantly increased resistance was observed in the free radical-induced hemolysis, especially in women, this effect was not observed in smokers. In total, the findings suggest the presence of familial effects in the response to ex vivo oxidation. Further, smoking negates the beneficial effect of exercise training on erythrocyte resistance to free radical-induced hemolysis. These observations emphasize the importance of context in the evaluation of exercise and oxidant stress.

Lycopene Intake and Prostate Cancer Risk: Effect Modification by Plasma Antioxidants and the XRCC1 Genotype

Lycopene has been associated with reduced prostate cancer risk, although the results of epidemiological studies have varied. We hypothesize that an effect of lycopene may be modified by XRCC1 genotype and other antioxidants. We used a food-frequency questionnaire to assess lycopene intake in a case-control study of prostate cancer in North Carolina. Plasma alpha-tocopherol and beta-carotene levels were measured using high-performance liquid chromatography. XRCC1 genotypes were detected using polymerase chain reaction-restriction fragment length polymorphism. The final dataset included 77 cases and 174 controls with complete questionnaires, genotyping, and plasma analyses. Among men with the Arg/Arg genotype at codon 399, odds ratios (ORs) for prostate cancer risk associated with medium (732-1,529 microg/day) and high (>1,529 microg/day) lycopene intake were 0.59 (95% confidence interval = 0.23-1.50) and 0.21 (0.06-0.71), respectively (P(trend) < 0.01). Similar analyses for persons with Arg/Gln or Gln/Gln genotypes produced null results. Above-median (1,048 microg/day) lycopene intake combined with above-median levels of alpha-tocopherol and beta-carotene was associated with an OR of 0.11 (0.02-0.65) among men with the Arg/Arg genotype but not those with at least one Gln allele (P(interaction) = 0.01). Although limited by small sample size, these findings indicate that the association between lycopene and prostate cancer is complex and may be modified by other antioxidants and by XRCC1 genotype.

Associations of serum carotenoid concentrations with the development of diabetes and with insulin concentration: interaction with smoking: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

Smoking is associated with low serum carotenoid concentrations. Prospective studies have found lower diabetes risk among persons with high-carotenoid diets. Whether diabetes risk is low in the rare smoker who has high serum carotenoid levels is unknown. The authors investigated the interaction of serum carotenoid concentrations and smoking with diabetes mellitus in 4,493 Black and White men and women aged 18-30 years in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. The authors assessed 15-year (1985-2001) incident diabetes (148 cases), insulin concentration, and insulin resistance (homeostasis model assessment) in smokers and nonsmokers according to baseline levels of serum alpha-carotene, beta-carotene, zeaxanthin, beta-cryptoxanthin, and lycopene. Diabetes incidence was inversely associated with the sum of carotenoid concentrations in nonsmokers (per standard deviation (SD) increase, relative hazard = 0.74, 95% confidence interval: 0.55, 0.99) but not in current smokers (relative hazard = 1.13, 95% confidence interval: 0.83, 1.53) (p for interaction = 0.02). Similarly, year 15 insulin and insulin resistance values, adjusted for baseline levels, were inversely related to sum of carotenoids only in nonsmokers (per SD increase in insulin level, slope = -0.46 (p = 0.03); per SD increase in insulin resistance, slope = -0.14 (p = 0.01)). In CARDIA, higher serum carotenoid concentrations are associated with lower risk of diabetes and insulin resistance in nonsmokers but not in smokers.

Longitudinal associations between body mass index and serum carotenoids: the CARDIA study

Cross-sectional studies report an inverse association between BMI and serum carotenoid concentration. The present study examined the prospective association between BMI and the serum concentration of five carotenoids in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Serum carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, zeaxanthin/lutein, lycopene), BMI, dietary intake, physical activity and dietary supplement use were measured at years 0 and 7 in 3071 black and white male and female participants, who were either persistent smokers or non-smokers. Among non-smokers, year 0 BMI predicted year 7 serum carotenoid levels: obese subjects (BMI > or =30 kg/m2) had an average concentration of the sum of four carotenoids (alpha-carotene +beta-carotene + zeaxanthin/lutein+beta-cryptoxanthin) that was 22 % lower than the concentration among subjects with a BMI of less than 22 kg/m2. In contrast, the sum of carotenoids among smokers was only 6 % lower. Relationships between BMI and serum lycopene were weak. The change from year 0 to year 7 in serum carotenoids, except for lycopene, was inversely associated with the change in BMI among non-smokers but not among smokers. Parallel findings were observed for BMI and serum gamma-glutamyl transferase level. In summary, the observation that BMI predicted the evolution of serum carotenoids during a 7-year follow-up among young non-smoking adults is consistent with the hypothesis that carotenoids are decreased in protecting against oxidative stress generated by adipose tissue, while smokers maintain a minimal level of serum carotenoids independent of adiposity. The results for lycopene were, however, discordant from those of the other carotenoids.

Associations of plant food, dairy product, and meat intakes with 15-y incidence of elevated blood pressure in young black and white adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

BACKGROUND

Consumption of plant foods and dairy and meat products may moderate increases in blood pressure.

OBJECTIVE

The objective was to evaluate associations of dietary intake with the 15-y incidence of elevated blood pressure (EBP; ie, incident systolic BP >or= 130 mm Hg, diastolic BP >or= 85 mm Hg, or use of antihypertensive medication).

DESIGN

Proportional hazards regression was used to evaluate relations of dietary intake at years 0 and 7 with the 15-y incidence of EBP in the Coronary Artery Risk Development in Young Adults (CARDIA) Study of 4304 participants aged 18-30 y at baseline.

RESULTS

EBP incidence varied from 12% in white women to 33% in black men. Plant food intake (whole grains, refined grains, fruit, vegetables, nuts, or legumes) was inversely related to EBP after adjustment for age, sex, race, center, energy intake, cardiovascular disease risk factors, and other potential confounding factors. Compared with quintile 1, the relative hazards of EBP for quintiles 2-5 of plant food intake were 0.83 (95% CI: 0.68, 1.01), 0.83 (0.67, 1.02), 0.82 (0.65, 1.03), and 0.64 (0.53, 0.90), respectively; P for trend = 0.01. Dairy intake was not related to EBP (P for trend = 0.06), and positive dose-response relations for EBP were observed across increasing quintiles of meat intake (P for trend = 0.004). In subgroup analyses, risk of EBP was positively associated with red and processed meat intake, whereas it was inversely associated with intakes of whole grain, fruit, nuts, and milk. Adjustment for intermediary factors in the causal pathway attenuated these relations.

CONCLUSION

These findings are consistent with a beneficial effect of plant food intake and an adverse effect of meat intake on blood pressure.

Hypoglycemic and antioxidant effect of oleuropein in alloxan-diabetic rabbits

Patients with diabetes mellitus are likely to develop certain complication such as retinopathy, nephropathy and neuropathy as a result of oxidative stress and overwhelming free radicals. Treatment of diabetic patients with antioxidant may be of advantage in attenuating these complications. Oleuropein, the active constituent of olive leaf (Olea europaea), has been endowed with many beneficial and health promoting properties mostly linked to its antioxidant activity. This study aimed to evaluate the significance of supplementation of oleuropein in reducing oxidative stress and hyperglycemia in alloxan-induced diabetic rabbits. After induction of diabetes, a significant rise in plasma and erythrocyte malondialdehyde (MDA) and blood glucose as well as alteration in enzymatic and non-enzymatic antioxidants was observed in all diabetic animals. During 16 weeks of treatment of diabetic rabbits with 20 mg/kg body weight of oleuropein the levels of MDA along with blood glucose and most of the enzymatic and non-enzymatic antioxidants were significantly restored to establish values that were not different from normal control rabbits. Untreated diabetic rabbits on the other hand demonstrated persistent alterations in the oxidative stress marker MDA, blood glucose and the antioxidant parameters. These results demonstrate that oleuropein may be of advantage in inhibiting hyperglycemia and oxidative stress induced by diabetes and suggest that administration of oleuropein may be helpful in the prevention of diabetic complications associated with oxidative stress.