Retinol, carotenoids, and tocopherols in the milk of lactating adolescents and relationships with plasma concentrations

OBJECTIVE: We determined the concentrations of retinol, carotenoids, and tocopherols in breast milk of adolescents and evaluated their associations with plasma levels and with maternal characteristics (period of lactation, body mass index, age of menarche, and years postmenarche). METHODS: This was a single cross-sectional survey of retinol, carotenoid, and tocopherol composition of milk and plasma of lactating adolescent mothers (n = 72; 30-120 d postpartum) attending public daycare clinics in Rio de Janeiro, Brazil. Milk and plasma components were analyzed by high-performance liquid chromatography. RESULTS: Nutrient concentrations (micromoles per liter, mean +/- SE) in plasma and milk were, respectively, retinol 2.1 +/- 0.5 and 0.62 +/- 0.44, beta-carotene 0.18 +/- 0.19 and 0.016 +/- 0.017, alpha-carotene 0.05 +/- 0.04 and 0.0035 +/- 0.002, lutein plus zeaxanthin 0.15 +/- 0.11 and 0.025 +/- 0.024, lycopene 0.1 +/- 0.11 and 0.016 +/- 0.025, alpha-tocopherol 10.8 +/- 5.3 and 2.7 +/- 1.8, gamma-tocopherol 2.6 +/- 2.3 and 0.37 +/- 0.15. The milk/plasma molar ratios of retinol and tocopherols were two times higher than those of carotenoids. Significant correlations (P < 0.001) between milk and plasma nutrient levels were observed for beta-carotene (r = 0.41), alpha-carotene (r = 0.60), and lutein plus zeaxanthin (r = 0.57), but not for lycopene, retinol, and tocopherols. Nutrient concentrations in plasma and in milk were not associated with the maternal characteristics investigated. CONCLUSION: Concentrations of the nutrients studied, especially retinol and alpha-tocopherol, in mature milk of lactating adolescents were, in general, lower than in milk of adult lactating women. Milk concentrations were associated with plasma concentrations only for beta-carotene, alpha-carotene, and lutein plus zeaxanthin.     

Relation between prenatal lipid-soluble micronutrient status, environmental pollutant exposure, and birth outcomes

BACKGROUND: Adverse postnatal health effects have been associated with compromised fetal growth, which makes it essential to understand its determinants. Significant effects of environmental pollutants on birth outcomes have been observed in our study population, and nutritional status may be an additional factor influencing fetal development and effects of environmental toxins. OBJECTIVE: The objective of the study was to examine the relations between birth outcomes and lipid-soluble plasma micronutrient concentrations and to explore interactions between micronutrients and environmental pollutant exposure in newborns in Krakow, Poland. DESIGN: In this prospective cohort study, retinol, alpha-tocopherol, and carotenoids were measured in maternal and cord blood samples obtained at delivery (251 maternal-newborn pairs), and birth weight, birth length, head circumference (HC), and gestational age were evaluated. Linear regression analysis was used to estimate the effects of micronutrients while covariates were controlled for. Interaction terms assessed whether the effects of polycyclic aromatic hydrocarbons (PAHs), common environmental pollutants, varied by nutrient status. RESULTS: Infants whose mothers had low plasma alpha-tocopherol concentrations (below the median) weighed 92.9 g less and had 0.41-cm smaller HCs than did infants whose mothers had high alpha-tocopherol concentrations. Infants with low plasma retinol (below the median) weighed 125.9 g less and had 0.31-cm smaller HCs. There was no evidence of an interaction between PAHs and micronutrients, although power was limited. CONCLUSION: Maternal alpha-tocopherol and cord retinol concentrations were significantly and positively associated with BW and HC. These micronutrients may have direct effects or may be markers for other underlying determinants of these pregnancy outcomes.     

Effect of beta-carotene supplementation on the concentrations and distribution of carotenoids,vitamin E,vitamin A,and cholesterol in plasma lipoprotein and non-lipoprotein fractions in healthy older women.

We studied the effect of beta-carotene supplementation on the concentrations and distribution in plasma lipoprotein and non-lipoprotein fractions of carotenoids, alpha-tocopherol, retinol, and cholesterol.

Ten women ingested either 90 mg of beta-carotene or placebo daily for 3 weeks while residing in their homes and eating their usual meals. Carotenoids (beta-carotene, lycopene, lutein/zeaxanthin), retinol, alpha-tocopherol, and cholesterol were measured in plasma lipoprotein and non-lipoprotein fractions before and after treatment.

In the beta-carotene-supplemented group, total plasma beta-carotene increased 14-fold from 0.48 +/? 0.13 to 6.83 +/? 2.12 mumol/L (p = 0.04). Although the greatest increase in beta-carotene was in low-density-lipoproteins (LDL), the magnitude of increase was similar in LDL, high-density-lipoproteins (HDL), and very-low-density-lipoproteins (VLDL). Thus, the relative distribution of beta-carotene in lipoproteins was unchanged: approximately 71% was in LDL, approximately 15% in HDL and approximately 12% in VLDL, before and after beta-carotene supplementation. There were no changes in amounts and distribution in lipoproteins of the other carotenoids, alpha-tocopherol, and cholesterol. There was no change in the amount of retinol in lipoprotein-deficient plasma. There were no changes in total plasma triglycerides. Significant positive correlations were found between LDL- or VLDL-cholesterol and alpha-tocopherol in LDL or VLDL, respectively; between LDL- or VLDL-cholesterol and lutein/zeaxanthin in LDL or VLDL, respectively; and between HDL-cholesterol and beta-carotene in HDL.

beta-Carotene supplementation (90 mg/day for 3 weeks) in healthy older women results in an enrichment of all plasma lipoprotein fractions with beta-carotene, but does not alter the relative distribution of beta-carotene in lipoproteins. beta-Carotene supplementation has no effect on the amounts and relative distribution of lycopene, lutein/zeaxanthin, and alpha-tocopherol in lipoproteins, or of retinol in the non-lipoprotein fraction of plasma. Short-term beta-carotene supplementation has no effect on the concentrations of plasma total triglycerides, total cholesterol, HDL-, LDL-, and VLDL-cholesterol.     

The relationship between reduced vitamin antioxidant concentrations and the systemic inflammatory response in patients with common solid tumours

BACKGROUND AND AIMS: The majority of patients with advanced cancer have reduced circulating concentrations of the vitamin antioxidants including retinol, alpha-tocopherol and carotenoids. However, the basis of this reduction is not known. Vitamin antioxidant concentrations have been reported to be correlated with a systemic inflammatory response (as evidenced by C-reactive protein) in normal subjects and in patients with lung cancer. In order to determine whether this relationship was independent of tumour type patients other common solid tumours were studied. METHODS: Fasting circulating concentrations of vitamin antioxidants and C-reactive protein were measured in normal subjects (n=30) and patients with breast (n=15), prostate (n=15) and colorectal cancer (n=11). RESULTS: Concentrations of C-reactive protein were higher (P<0.0001) and vitamin antioxidants lower (P<0.0001) in the cancer patients. In normal subjects and cancer patients, C-reactive protein concentrations were inversely correlated with circulating concentrations of retinol (r(2)=0.162), alpha-tocopherol (r(2)=0.297), lutein (r(2)=0.256), lycopene (r(2)=-0.171), alpha-(r(2)=0.140) and beta-carotene (r(2)=0.254): (all P<0.001). CONCLUSIONS: Concentrations of retinol, alpha -tocopherol and carotenoids are inversely associated with the magnitude of the systemic inflammatory response. These relationships appear to be independent of the presence and type of cancer.     

Relationship of Plasma Carotenoids,Retinol and Tocopherols in Mothers and Newborn Infants

Objective:We studied the relationship between maternal and cord plasma concentrations of carotenoids, retinol, and tocopherols in normal mother-baby pairs.

Methods: Healthy pregnant women (n=10) were recruited at a Montréal hospital. Venous blood samples were collected from the mothers at delivery and cord blood was obtained immediately post partum from the umbilical vein after clamping of the cord. All deliveries were full term deliveries and all babies had normal birth weights. Maternal and umbilical cord blood samples were handled identically. Plasma was digested with lipase and plasma carotenoids were extracted and measured using HPLC.

Results: Cord plasma concentration of carotenoids were significantly lower than that of maternal plasma (p<0.001). There was a high correlation of lutein (r=0.889, p=0.006) and cryptoxanthin (r=0.912, p=0.0002) between maternal plasma concentrations and cord plasma concentrations. The concentrations of the hydrocarbon carotenoids, α-carotene and β-carotene, were also correlated (r=0.779, p=0.0133, & r=0.782, p=0.0076, respectively) between maternal plasma and cord plasma. Whereas the plasma concentration of the acyclic carotenoid, lycopene, showed no correlation between the two groups, after adjustment for plasma triglycerides, the lycopene correlation between maternal and cord plasma was the highest (r=0.975, p=0.0001) of all the carotenoids tested. Cord plasma retinol concentration, which was 50% of that of maternal plasma, was also found to have no correlation with that of maternal plasma. Plasma concentration of α-tocopherol showed no correlation between two groups, whereas there was high correlation between cord and maternal γ-tocopherol concentrations (r=0.808, p=0.0047).

Conclusion: The nutritional status of mothers affects the nutritional status of their babies for certain fat soluble nutrients.     

Concentrations of tocopherols and carotenoids in maternal and cord blood plasma.

OBJECTIVES: To determine the levels of tocopherols, retinol and carotenoids in maternal and umbilical cord blood plasma and to investigate the relationships between them. DESIGN: Venous blood plasma concentrations of alpha, gamma and delta-tocopherol, retinol, lutein, lycopene, zeaxanthin, beta-cryptoxanthin, alpha and beta-carotene were determined by HPLC in healthy pregnant women and in pair-matched umbilical cords. Plasma levels of triglycerides and cholesterol were also measured. SUBJECTS: Sixty-six women, between 10 and 20 weeks gestation, were recruited randomly during their first antenatal appointment. From this group, 40 pair-matched umbilical cord blood samples were obtained. RESULTS: Tocopherols, retinol, carotenoids and lipids were present in significantly higher (P < 0.001) concentrations in maternal plasma than in cord plasma. There was a significant correlation (r = 0.45, P < 0.005) between maternal and cord levels of gamma-tocopherol, but not of alpha-tocopherol, retinol or carotenoids. Tocopherols and carotenoids were significantly correlated with each other (P < 0.05) in maternal and cord plasma. CONCLUSIONS: Plasma levels of tocopherols, carotenoids and lipids are substantially lower at birth than in adulthood. There is a clear relationship between gamma-tocopherol levels in maternal and cord plasma. The importance of gamma-tocopherol in human nutrition should be further investigated. There are no significant relationships between plasma alpha-tocopherol and carotenoids in pregnant mothers and cords. More research is needed to elucidate the maternal-foetal transfer of tocopherols and carotenoids, and to examine the impact of maternal antioxidant nutrient status on neonatal antioxidant capacity. It is important to determine if a low level of tocopherols and carotenoids at birth is a normal stage of human development or indicative of deficiency.     

Relationship between smoking, dietary intakes and plasma levels of vitamin E and beta-carotene in matched maternal-cord pairs.

The concentrations of tocopherols and carotenoids are lowered in umbilical cord blood plasma, which may have a negative effect on antioxidant protection in neonates. Smoking may adversely affect dietary intakes and plasma concentrations of carotenoids. The dietary intakes of vitamin E and beta-carotene were assessed in 66 pregnant women (31 smokers and 35 non-smokers) between 10 and 20 weeks gestation using a food frequency questionnaire. The concentrations of alpha-tocopherol and beta-carotene were measured in maternal plasma at the time of the dietary assessment, and in the matched umbilical cords of their newborn after delivery. In smoking and non-smoking mothers, the mean intakes of vitamin E (9.3 [SD 5] and 8.2 [SD 5] mgd-1) and beta-carotene (3464 [SD 1885] and 2977 [SD 1503] micrograms d-1) were not significantly different. The plasma concentrations of alpha-tocopherol (20.8 [SD 4] and 20.5 [SD 4] mumol L-1), the alpha-tocopherol to lipid ratios (3.2 [SD 0.8] and 3.5 [SD 0.8]) and the plasma concentrations of beta-carotene (0.22 [SD 0.1] and 0.22 [SD 0.1] mumol L-1) were not significantly different in smoking and non-smoking mothers. There were no significant differences in plasma alpha-tocopherol (7.4 [SD 2] and 7.3 [SD 2] mumol L-1), in alpha-tocopherol to lipid ratios (3.2 [SD 0.6] and 2.8 [SD 0.6]) or in beta-carotene concentrations (0.05 [SD 0.04] and 0.03 [SD 0.02] mumol L-1) in cords from newborns of smoking and non-smoking mothers. There was a significant correlation (r = 0.41, P = 0.015) between dietary intakes and plasma concentrations of beta-carotene in non-smoking mothers. However, this relationship was not significant in smoking mothers (r = 0.28, P = 0.12). There were no relationships between dietary intakes and plasma concentrations of tocopherol. These results indicate that smoking during pregnancy does not appear to affect the dietary intakes or plasma concentrations of alpha-tocopherol and beta-carotene in pregnant women or their babies. However, smoking does influence the relationship between dietary intakes and plasma levels of beta-carotene.     

Plasma levels of retinol, carotenoids, and tocopherols in relation to dietary pattern among pregnant Tanzanian women

In Tanzania, as in other developing countries, dietary intake of nutrients in pregnant women is marginal or lower than the recommended intakes and therefore these women are at high risk for deficiencies. Our aim was to evaluate the relationship between diet and plasma levels of retinol, carotenoids, and alpha-tocopherol in the third trimester of pregnancy. Ninety pregnant women aged between 18 and 45 years were equally recruited from three villages. Seven-day food frequency data was collected by questionnaire. Plasma levels of retinol, carotenoids, and tocopherols were assessed by high-performance liquid chromatography (HPLC). Results indicated that cooked green leafy vegetables constituted the major source of provitamin A carotenoids, with low intake of yellow/orange fruits and preformed vitamin A. Lutein, lycopene, and beta-carotene were the predominant carotenoids in the plasma with mean values of 1.61, 0.84, and 0.63 mumol/L, respectively. There was no significant correlation between frequencies of vegetable consumption and either plasma retinol or carotenoids. However, increased consumption of green leafy vegetables with oil, which increases bioavailability, was correlated with high plasma retinol levels (p = 0.03). Low retinol levels (< or = 0.70 mumol/L) were present in 26% of women. The mean plasma retinol concentration was 0.89 mumol/L and 63% of the women had values below 1.05 mumol/L. The mean plasma alpha-tocopherol concentration was 15.4 mumol/L and women with plasma retinol concentration > 1.05 mumol/L had significantly higher mean alpha-tocopherol than women with plasma retinol concentration < or = 0.70 mumol/L (p < or = 0.01). Twenty-four percent of the women were anemic (hemoglobin: Hb < 110 g/L) and the mean Hb value was 116.3 g/L.     

Plasma concentrations of carotenoids, retinol, and tocopherols in preeclamptic and normotensive pregnant women

This case-control study was conducted in Lima, Peru, from June 1997 through January 1998 to assess whether plasma concentrations of carotenoids (alpha-carotene, beta-carotene, lycopene, lutein, zeaxanthin, beta-cryptoxanthin), retinol, and tocopherols (alpha-tocopherol and gamma-tocopherol) are decreased in women with preeclampsia. A total of 125 pregnant women with preeclampsia and 179 normotensive pregnant women were included. Plasma concentrations of antioxidants were determined using high performance liquid chromatography. After adjusting for maternal demographic, behavioral, and reproductive characteristics and total plasma lipid concentrations, the authors found a linear increase in risk of preeclampsia with increasing concentrations of alpha-tocopherol (odds ratio of the highest quartile = 3.13; 95% confidence interval: 1.06, 9.23, with the lowest quartile as the reference group; p value of the test of linear trend = 0.040). The risk of preeclampsia decreased across increasing quartiles of concentrations for retinol (odds ratio of the highest quartile = 0.32; 95% confidence interval: 0.15, 0.69, with the lowest quartile as the reference group; p value of the test of linear trend = 0.001). Some of these results are inconsistent with the prevailing hypothesis that preeclampsia is an antioxidant-deficient state. Preliminary findings confirm an earlier observation of increased plasma concentrations of alpha-tocopherol among women with preeclampsia as compared with normotensive pregnant women.     

Plasma carotenoid and vitamins a and e concentrations in older African American women after wheat bran supplementation: effects of age, body mass and smoking history

OBJECTIVE: This study investigated the relationships of plasma vitamins A, E, and carotenoids with age, BMI and former/non-smoking history after adjusting for wheat bran supplementation. METHODS: All 39 African American women in the church-based, volunteer sample, 40-70 years old, supplemented their daily diets for 5-6 wks. with 1/2 cup of a riboflavin-spiked wheat bran cereal. RESULTS: Urinary riboflavin concentrations increased from 0.8 +/- 0.1 mg/day at baseline to 7.5 +/- 0.5 mg/day after supplementation, confirming the 99.2 +/- 10.5% self-reported adherence. Plasma nutrient concentrations did not change significantly with supplementation nor was never/former smoking history related to diet. Plasma retinol and serum cholesterol were significantly higher (p < 0.0002) in persons older than 55 years compared to younger adults. Plasma retinol (microg/dL) but not serum cholesterol was associated significantly with menopausal status and hormone replacement therapy (HRT; p = 0.05); progressive increases in retinol concentrations were found in the women after adjusting for pre/post supplementation: lowest in pre-menopause (47.7 +/- 4.8); intermediate concentrations in post-menopause on HRT (54.6 +/- 3.0); highest level in post-menopause without HRT (61.1 +/- 3.0). Similarly, a progressive increase was found in lipid-unadjusted alpha-tocopherol concentrations and menopausal status with or without HRT. Vitamin A and cholesterol intakes were not significantly different by age group. Plasma carotenoids were not significantly different by age or fiber supplementation, but alpha- and beta-carotene and beta-cryptoxanthin were significantly lower with BMI > or = 30. In contrast to carotenoids, both plasma levels of gamma-tocopherol and lipid-adjusted gamma-tocopherol were significantly higher with obesity compared to those with BMI < 30. CONCLUSION: Plasma alpha- and beta-carotene and beta-cryptoxanthin were negatively associated with obesity, whereas gamma-tocopherol measures were consistently elevated with high BMI. The increase in age-associated plasma retinol in postmenopausal women was likely related to decreased estrogen concentrations in the African American women. Smoking history was not influential in this study.     

Relationship between carotenoids and anaemia during acute uncomplicated Plasmodium falciparum malaria in children

A clinic-based cohort study in Kampala, Uganda, was conducted to examine the relationship between severe malarial anaemia and plasma micronutrients. Plasma carotenoids, retinol, vitamin E, and four trace metal concentrations were measured at enrollment and seven days later in 273 children, aged 1-10 year(s), with acute, uncomplicated Plasmodium falciparum malaria. Concentrations of plasma provitamin A carotenoids (p < 0.0001), non-provitamin A carotenoids (p < 0.0001), retinol (p < 0.0001), all four trace elements (all p < 0.001), and vitamin E (p < 0.0001) rose significantly by day 7 among children without severe anaemia (haemoglobin 70 g/L). There was no change in provitamin A carotenoids (p = 0.24) among children with severe anaemia (haemoglobin <70 g/L), whereas non-provitaminAcarotenoids (p < 0.0001), retinol (p < 0.0001), and vitamin E (p = 0.011) increased. These observations also support the hypothesis that the use of provitamin A carotenoids increases during malaria infection.     

Vitamins A, E, and carotene: effects of supplementation on their plasma levels

We conducted a randomized, double-blind trial among 59 generally well-nourished adults to determine the effects of vitamin A, vitamin E, and beta-carotene supplements on plasma retinol, alpha-tocopherol, and carotenoid levels. Over a period of 16 wk a daily alpha-tocopherol supplement of 800 IU approximately doubled plasma alpha-tocopherol levels (p less than 0.001), caused a small decrease in plasma carotenoids (p = 0.02), and produced a slight and statistically insignificant reduction in plasma retinol. A daily beta-carotene supplement of 30 mg (5000 retinol equivalents) approximately tripled plasma carotenoid levels (p less than 0.001) but did not affect plasma retinol or alpha-tocopherol. A daily retinyl palmitate supplement of 25,000 IU (13,750 retinol equivalents) did not appreciably affect plasma retinol, alpha-tocopherol, or carotenoid.     

Dietary intakes and serum concentrations of vitamin E and total carotenoids of healthy adults with severe physical disabilities are lower than matched controls

Millions of people worldwide have severe chronic physical disabilities (e.g., polio, spinal cord injury). We hypothesized that these people are at risk for poor antioxidant nutrient intakes and status, because of their typically low energy expenditures and low socioeconomic status. We surveyed antioxidant nutrient intakes and concentrations in subjects with physical disabilities and age matched non-disabled controls. Only one subject with physical disabilities ate five or more servings of vegetables per day. The group had low intakes of vegetables (minus potatoes) and citrus fruits, and trends for low intakes of all antioxidant nutrients. Serum a-tocopherol and total carotenoid concentrations were lower in subjects with physical disabilities, while retinol and individual carotenoids showed non-significant lower trends. Since adequate antioxidant nutrients are associated with decreased chronic disease risk, nutrition professionals might improve the health of patients with physical disabilities by periodically monitoring their intakes and status of antioxidant nutrients. J Am Diet Assoc. 2002; 102:1804-1806.     

Carotenoid composition of human milk during the first month postpartum and the response to beta-carotene supplementation

BACKGROUND: Information is lacking regarding normal changes in milk carotenoid concentrations in healthy, well-nourished women during the first month of lactation. OBJECTIVES: This study investigated milk carotenoid concentrations during days 4-32 postpartum and assessed the effects of maternal beta-carotene supplementation. DESIGN: Subjects (n = 21; aged 19-39 y) were randomly assigned to receive beta-carotene (30 mg/d) or placebo from days 4 to 32 postpartum. Each subject provided 8 diet records and 8 milk samples during the study. Diet records were analyzed for energy, macronutrients, vitamins A and E, and carotenoids. Milk samples were analyzed with HPLC for concentrations of carotenoids, retinol, and alpha-tocopherol. Data were analyzed by using repeated-measures analysis and orthogonal contrasts. RESULTS: No significant differences in average dietary intakes, body mass index, age, or parity were found between groups at baseline or after supplementation. Milk carotenoid concentrations decreased over time (P < 0.01), as did retinol and alpha-tocopherol concentrations (P < 0.003). Concentrations of most carotenoids decreased to those reported for mature milk by day 32 postpartum. Milk lutein concentrations remained elevated throughout the study compared with values reported for mature milk, whereas plasma lutein concentrations decreased significantly over time. beta-carotene supplementation did not significantly change the milk concentrations of beta-carotene, the other carotenoids, retinol, or alpha-tocopherol. CONCLUSIONS: The lack of increase in milk beta-carotene despite supplementation suggests that transitional milk may be already nearly saturated with beta-carotene. The elevated milk lutein concentration and simultaneous decrease in plasma lutein suggest that lutein metabolism may be altered during early lactation.     

Zinc plus beta-carotene supplementation of pregnant women is superior to beta-carotene supplementation alone in improving vitamin A status in both mothers and infants

BACKGROUND: Deficiencies of vitamin A, iron, and zinc are prevalent in women and infants in developing countries. Supplementation during pregnancy can benefit mother and infant. OBJECTIVE: We examined whether supplementation during pregnancy with iron and folic acid plus beta-carotene or zinc or both improves the micronutrient status of mothers and infants postpartum. DESIGN: Pregnant women (n = 170) were supplemented daily only during pregnancy with beta-carotene (4.5 mg), zinc (30 mg), or both or placebo plus iron (30 mg) and folic acid (0.4 mg) in a randomized, double-blind, placebo-controlled trial. Micronutrient status was assessed 1 and 6 mo postpartum. RESULTS: Six months postpartum, plasma retinol concentrations were higher in the women who received zinc during pregnancy than in women who did not. Infants born to mothers supplemented with beta-carotene + zinc had higher plasma retinol concentrations, with the frequency of vitamin A deficiency reduced by >30% compared with the other 3 groups. Breast-milk beta-carotene concentrations were higher in all women supplemented with beta-carotene, but breast-milk retinol concentrations were higher only in women who received beta-carotene + zinc. Zinc concentrations did not differ among groups in mothers and infants. CONCLUSIONS: Zinc supplementation during pregnancy improved the vitamin A status of mothers and infants postpartum, which indicates a specific role of zinc in vitamin A metabolism. Addition of both beta-carotene and zinc to iron supplements during pregnancy could be effective in improving the vitamin A status of mothers and infants.     

Serum Retinol Concentrations in Mothers and Newborns at Delivery in a Public Maternity Hospital in Recife,Northeast Brazil

Serum retinol concentrations were compared in a consecutive series of 65 mother-newborn pairs at delivery in a public maternity hospital in Recife, Brazil, from January to August 2008 and examined their association with biological, socioeconomic, environmental and obstetrical characteristics. Serum retinol concentrations of the newborns (umbilical cord) and mothers (brachial venipuncture) were analyzed by high-performance liquid chromatography. Prevalence of low (<0.70 µmol/L) and inadequate (<1.05 µmol/L) serum retinol concentrations were observed in 23.1% (95% CI 13.9-35.5) and 23.0% (95% CI 13.5-35.8) among newborns and mothers respectively. The serum retinol distribution was lower in male than female infants (-0.4 µmol/L, p=0.01) and, across both sexes, concentrations in paired newborn and mother were correlated (r=0.27, p=0.04). Further, maternal status explains only 7% of the variance in retinol concentrations in newborn''s cord plasma. Among mothers delivering in public facilities in Recife, hypovitaminosis may exist.Key words: Case series, Mother-infant dyad, Serum retinol, Vitamin A deficiency, Brazil     

Clinical and analytical evaluation of the simultaneous HPLC assay of retinol and alpha-tocopherol

We describe a method for the simultaneous assay of retinol and alpha-tocopherol using normal-phase, high-performance liquid chromatography (HPLC). Our normal-phase HPLC method gave better resolution (Rs) of retinol (Rs= 1.58) and alpha-tocopherol (Rs = 1.40) when compared with the Rs values for a-tocopherol and retinol from literature. Also, the alpha-tocopherol concentrations obtained by our method agreed well with another normal-phase HPLC method that used fluorometric detection (r = 0.951, p<0.001. Sy.x=0.58 mg/L). The concentrations of retinol in our method agreed well with those determined by a reversed-phase HPLC procedure, although the correlation (r=0.646, p<.001, Sy.x=62 microg/L) was not as good as the method proposed. Our procedure gave acceptable precision: the within-run CV was 7.7% for alpha-tocopherol and 5.9% for retinol. The between-day CV was 9.0% for alpha-tocopherol and 6.8% for retinol. The mean recoveries were 97% for alpha-tocopherol and 107% for retinol. Our assays were linear for alpha-tocopherol concentrations from 0.1 to 30 mg/L and for retinol concentrations from 20 to 2,000 microg/L. In children ages 7 to 12 y, and in adolescents ages 14 to 16 y, the alpha-tocopherol and retinol concentrations in the blood were significantly lower than the concentrations in normal adults. Individuals over 70 y old also showed alpha-tocopherol and retinol values that were lower than those of normal adults between ages 30 and 40 y. In female university students, the inter-individual variation of alpha-tocopherol was reduced by dividing the alpha-tocopherol results by their total cholesterol or total lipid concentrations; however, this was not obtained for retinol. In cancer patients undergoing surgery, the ratio of retinol to retinol-binding protein (RBP) remained fairly constant, although the concentrations of both retinol and RBP decreased to about one-half the preoperative values after surgery. We conclude that our normal-phase HPLC method is a stable and reproducible method for alpha-tocopherol and retinol, and is an easy-to-use analytical tool.     

Prostatic levels of tocopherols, carotenoids, and retinol in relation to plasma levels and self-reported usual dietary intake

This study evaluated how prostatic levels of antioxidants relate to plasma levels and self-reported usual dietary intake. Definition of these relations may aid in interpreting studies of antioxidant exposure and prostate cancer risk. Between July 1996 and April 1997, plasma and prostatic tissue levels of tocopherols, carotenoids, and retinol were measured in 47 men undergoing radical prostatectomy or transurethral prostatectomy at Loyola University Medical Center, Maywood, Illinois, and an affiliate hospital. Dietary intake was measured by using a 122-item version of the Block Health Habits and History Questionnaire, and correlations were assessed with Pearson's coefficients. Prostatic levels of tocopherols and carotenoids (but not retinol) were significantly correlated with plasma levels (r= 0.31-0.56, p < 0.05-0.0001); the strongest correlations were associated with lycopene, beta-carotene, and gamma-tocopherol (0.56, 0.54, and 0.52, respectively; p < 0.0001). Relative concentrations of tocopherols and carotenoids in prostate tissue were proportionate to those in plasma. No correlation between prostatic levels and reported dietary intake was observed (r = -0.09 to 0.16, p < not significant). Adjustment for energy intake, body mass index, and serum lipids did not impact these relations. These results suggest that plasma levels of tocopherols and carotenoids better reflect prostatic exposure than self-reported usual dietary intake.     

Low plasma lycopene concentration is associated with increased mortality in a cohort of patients with prior oral, pharynx or larynx cancers

OBJECTIVE: This analysis was conducted to evaluate the association between plasma beta-carotene, alpha-carotene, lycopene, lutein/zeaxanthin, total carotenoids, retinol, alpha-tocopherol and subsequent mortality. METHODS: Blood samples collected longitudinally from 259 participants in a chemoprevention trial aimed at the prevention of second cancers of the oral cavity, pharynx, or larynx were analyzed by high performance liquid chromatography for selected micronutrients. All-cause mortality (primary outcome) and cause-specific mortality (secondary outcomes) were evaluated in relation to plasma micronutrient concentrations at baseline and longitudinally. RESULTS: A total of 61 deaths occurred over a follow-up time of up to 90 months. Cox proportional hazards models with time-dependent covariates were used for data analyses. In models adjusted for age, plasma cholesterol, time-dependent smoking, treatment arm, study site and gender, only plasma lycopene was significantly inversely associated with total mortality [hazard ratio (HR) above versus below median = 0.53, 95% confidence interval (CI) 0.30-0.93]. Plasma alpha-carotene was inversely associated (HR 0.24, 95% CI 0.08-0.75) while plasma retinol was positively associated (HR 5.12, 95% CI 1.54-17.05) with cardiovascular death. Smoking status modified plasma nutrient associations with total mortality. Lycopene (HR 0.08, 95% CI 0.02-0.36), alpha-carotene (HR 0.25, 95% CI 0.09-0.73) and total carotenoids (HR 0.22, 95% CI 0.07-0.70) were inversely associated with mortality in non-smokers, while plasma retinol (HR = 3.56, 95% CI 1.40-9.09) and alpha-tocopherol (HR = 2.47, 95% CI 1.02-5.98) were positively associated with mortality in smokers. CONCLUSIONS: Only plasma lycopene was significantly associated (inversely) with total mortality in the full study population. Smoking modifies associations between nutrients and mortality.     

Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study

BACKGROUND: The role of antioxidants in the pathogenesis of type 2 diabetes is uncertain. OBJECTIVE: We evaluated cross-sectional relations of dietary intakes and plasma concentrations of antioxidants with glucose metabolism in a high-risk population. DESIGN: The subjects were 81 male and 101 female first- and second-degree, nondiabetic relatives of patients with type 2 diabetes. Antioxidant intake data were based on 3-d food records. Subjects taking supplements containing beta-carotene or alpha-tocopherol were excluded. Plasma antioxidant concentrations were measured by HPLC. By using multiple linear regression analysis and adjusting for demographic, anthropometric, and lifestyle covariates, we studied whether dietary and plasma alpha- and beta-carotene, lycopene, and alpha- and gamma-tocopherol were related to fasting and 2-h concentrations of glucose and nonesterified fatty acids during an oral-glucose-tolerance test, to the homeostasis model assessment index of insulin resistance, and to measures of beta cell function (incremental 30-min serum insulin concentration during an oral-glucose-tolerance test and first-phase insulin secretion during an intravenous-glucose-tolerance test). RESULTS: In men, dietary carotenoids were inversely associated with fasting plasma glucose concentrations (P < 0.05), plasma beta-carotene concentrations were inversely associated with insulin resistance (P = 0.003), and dietary lycopene was directly related to baseline serum concentrations of nonesterified fatty acids (P = 0.034). In women, dietary alpha-tocopherol and plasma beta-carotene concentrations were inversely and directly associated, respectively, with fasting plasma glucose concentrations (P < 0.05). In both sexes, cholesterol-adjusted alpha-tocopherol concentrations were directly associated with 2-h plasma glucose concentrations (P < 0.05). CONCLUSION: The data suggest an advantageous association of carotenoids, which are markers of fruit and vegetable intake, with glucose metabolism in men at high risk of type 2 diabetes.