Serum Antioxidant Concentrations Research Articles

Importance of Microminerals for Maintaining Antioxidant Function After COVID-19-induced Oxidative Stress.

COVID-19 is caused by the Severe Acute Respiratory Distress Syndrome Coronavirus 2. Since the antioxidant mechanisms such as glutathione peroxidase or superoxide dismutase are downregulated during infection by the virus, there is an imbalance in the oxidant-antioxidant system. In this study we aimed to identify the effect of COVID-19 on the antioxidant defense mechanism by comparing the concentrations of antioxidants and microminerals in COVID-19 patients and healthy controls. This cross-sectional analytical study involved 200 patients at Kasturba Hospital, Manipal University. The serum concentrations of antioxidants and minerals were determined to establish the impact of COVID-19 on antioxidants mechanism and nutrient status in COVID-19 patients. The serum concentrations of GPX (10.36 ± 2.70 ≥ 5.82 ± 1.64 mKAT/L, p < 0.0001) and copper (2192.5 ± 449.8 ≥ 782.15 ± 106.5 µg/dL, p < 0.0001) were significantly greater, and zinc (34.78 ± 4.5 ≤ 81.07 ± 10.13 µg/dL, p < 0.0001) was significantly less, in the study group than in controls. The Pearson correlation between serum SOD and zinc was significant (r = 0.491, p < 0.0001) indicating the importance of zinc in maintaining and improving SOD activity. No significant correlations were observed between copper and SOD (r = -0.089) or iron and CAT (r = -0.027). Our study demonstrated the expected increase in oxidant-radical production during COVID-19 by estimating the altered concentrations of antioxidants and the minerals required to neutralize the elevated ROS. This finding is not novel but adds to the existing literature, which recommends nutritional supplementation of microminerals and antioxidants.

Effect Modification of Selenium Supplementation by Intake and Serum Concentrations of Antioxidants on the Development of Metachronous Colorectal Adenoma

BackgroundSelenium (Se) is a trace element that has been investigated as a potential chemopreventive agent for colorectal cancer. Dietary intake of other antioxidant nutrients may modify the effect of Se.ObjectiveWe examined the association between intake and serum concentrations of retinol, β-carotene, β-cryptoxanthin, lycopene, lutein/zeaxanthin, and α- and γ-tocopherol and the development of metachronous colorectal adenoma, and if these nutrients modified the effect of Se.MethodsWe conducted a prospective study of 1874 participants from the Se Trial with data for antioxidant intake, as well as a subcohort of 508 participants with serum biomarker concentrations.ResultsStatistically significantly lower odds for the development of metachronous adenoma were observed for those participants in the highest tertile of intake for lutein/zeaxanthin compared to the lowest, with an OR (95% CI) of 0.72 (0.56-0.94). No effect modification for intake of any nutrient was observed. However, circulating concentrations of lycopene exhibited statistically significant effect modification of selenium supplementation (p < 0.06),ConclusionThese findings show that intake and circulating concentrations of antioxidant nutrients were not consistently associated with reduced odds for the development of metachronous lesions, although blood concentrations of lycopene may modify the effect of selenium supplementation.

Interaction between and impact of IL-6 genotype and alpha-tocopherol levels on periodontal condition in aging individuals.

Few studies have assessed the possible interaction between and impact of IL-6 variants and serum α-tocopherol levels on periodontal condition in older individuals. Here, we assessed the relationship between IL-6 variants and serum α-tocopherol levels on periodontal condition by considering effect modification. Among the study participants, 359 who were 71years of age underwent a dental examination, biochemical analysis, and interview. After dividing the participants into tertiles based on serum α-tocopherol levels, we conducted Poisson regression analysis to compare the prevalence rate ratio (PRR) for periodontal disease markers with the IL-6 genotype (rs1800796) based on each tertile adjusted by the number of teeth present (offset). The PRRs of the IL-6 genotype for periodontal condition (probing pocket depth [PPD], clinical attachment level [CAL], and bleeding on probing [BOP]) which were adjusted by the number of teeth present (offset) were 1.17 (P<.001), 1.37 (P<.001), and 1.08 (P=.048), respectively. In addition, a significant association was found between the reciprocal number of PRRs of the IL-6 genotype and three serum α-tocopherol levels. The adjusted PRRs (± standard error) of the IL-6 genotypes for PPD were 0.48 (0.12) for the first group (P<.001), 1.54 (0.04) for the second group (P<.001), and 2.11 (0.03) for the third group (P<.001); similar tendencies were seen for CAL and BOP. The results of this study suggest a potential association between the IL-6 genotype and periodontal condition in relation to serum antioxidant concentrations.

Serum Antioxidant Status and Cause-Specific Mortality in US Adults: Results from the National Health and Nutrition Examination Survey (NHANES) 1999–2002

Abstract Objectives Oxidative stress is one of the most important risk factors of non-communicable diseases. Studies on the association of serum antioxidants with mortality in a representative sample of US adults are still limited with inconsistent results. The objective of this study was to examine associations between serum concentrations of antioxidants (vitamins A and E, γ-tocopherol, total carotenoids, and β-carotene) and mortality among US adults. Methods The study cohort included adults aged ≥20 years who participated in the National Health and Nutrition Examination Survey (NHANES) 1999–2002, with measured serum antioxidants and mortality follow-up through December 31st, 2015 (N = 10,291). Outcomes were all-cause, cancer, and cardiovascular (CVD) mortality. Cox Proportional Hazards modelling was used to estimate adjusted hazards ratios (aHR) and 95% confidence intervals (CIs) for associations between serum antioxidant levels and mortality. Results Median follow-up was 14.2 years, with 2708 deaths, 556 from CVD, and 471 from cancer. Overall, a high level of vitamin E (&amp;gt;1529.5 ug/dL) was associated with increased risk of all-cause mortality (aHR: 1.3; 95% CI: 1.10, 1.54), while a low carotenoid level (&amp;lt;46.73 ug/dL) was associated with increased risk of all-cause mortality (aHR: 1.25; 95% CI: 0.88, 1.43). Vitamin A, γ-tocopherol, and β-carotene were not associated with mortality. The positive association between vitamin E and all-cause mortality was stronger among non-Hispanic whites (aHR: 1.37; 95% CI: 1.15, 1.65). Among Hispanics, compared to participants with vitamin A levels between 48.41–58.93 (ug/dL), participants in the highest vitamin A quartile (&amp;gt;70.54 ug/dL) had increased risk of all-cause and CVD mortality, while the third quartile (58.94–70.54 ug/dL) had reduced risk of cancer mortality. Among non-Hispanic blacks, total carotenoid levels between 63.60–87.24 (ug/dL) were negatively associated with all-cause mortality and vitamin E levels between 1154.57–1529.54 (ug/dL) were associated with decreased risk of cancer mortality, while high vitamin A levels were associated with increased CVD mortality. Conclusions Findings suggest that optimal levels of serum antioxidants may protect against mortality, with differences between race/ethnicity. Further studies in minority populations are warranted to confirm the findings. Funding Sources N/A.

Serum beta-carotene modifies the association between phthalate mixtures and insulin resistance: The National Health and Nutrition Examination Survey 2003–2006

Animal models suggest a protective role of antioxidants against the adverse effect of di-2-ethylhexyl phthalate (DEHP) on insulin resistance. However, no epidemiologic study has examined the effects observed in the animal model. We conduct a study to examine associations of urinary concentrations of phthalate metabolites (individually and as a mixture) with insulin resistance, along with potential effect modification by serum antioxidant concentrations. This cross-sectional study included 1605 participants (51% males) aged 12–85 from the National Health and Nutrition Examination Surveys (2003–2006). Urinary concentrations of 9 phthalate metabolites were measured from spot urine samples. Antioxidant (vitamin A, C, E, and carotenoids) concentrations were measured from a fasting serum sample. We used Bayesian Kernel Machine Regression (BKMR) to evaluate associations between phthalate metabolite mixtures and insulin resistance, and examined whether serum antioxidant levels modified these associations, while accounting for the correlations of multiple concurrent exposures. A change in urinary ΣDEHP concentrations from the 25th to the 75th percentile was associated with a higher log HOMA-IR of 0.07 (95% CI = 0.01, 0.14) (4.85% increase in HOMA-IR). In contrast, the same change in urinary monoethyl phthalate (MEP) was associated with a lower HOMA-IR of −0.07 (95% CI = −0.14, −0.02) (6.68% decrease in HOMA-IR). The positive association between ΣDEHP and HOMA-IR became weaker at higher concentrations of serum β-carotene. The relationship between MEP and HOMA-IR, however, was not modified by the serum antioxidants examined. The remaining phthalate metabolites were unrelated to HOMA-IR. In this cross-sectional study, the positive association between DEHP exposure and insulin resistance weakened among participants with higher concentrations of serum β-carotene. As this is the first human report on the protective role of serum β-carotene on DEHP induced insulin resistance, future studies are needed.

Molecular analysis of the gut microbiome of diabetic rats supplemented with prebiotic, probiotic, and synbiotic foods

Beneficial symbionts residing in our gut have positive therapeutic effects on several metabolic disorders including diabetes. Oral administration of probiotic and prebiotic foods strengthens the beneficial symbiont populations in the gut and may prevent immune-mediated destruction of pancreatic β-cells. The present study was designed to elucidate the gut microbiome of diabetic rats supplemented with a Lactobacillus probiotic and a Saccharomyces cerevisiae (SC) cell wall prebiotic. Diabetes mellitus was induced in male Wistar rats with allaxon monohydrate (150 mg/kg). The rats were fed chow maintenance diet (control and diabetic control groups) or the same diet supplemented with a SC prebiotic (1 %), probiotic (multispecies Lactobacillus @108 CFU), or synbiotic. On d30, DNA was extracted from colon digesta for 16S ribosomal RNA (rRNA) gene sequencing. Serum was obtained to estimate total oxidant and anti-oxidant concentrations. A distinct clustering pattern (Unifrac distances, analysis of similarities (ANOSIM) P = 0.0361) was observed for the different treatment groups, with the main distinction consisting of the separation between the control and the diabetic control groups. Distinct bacterial clades dominated different treatment groups, particularly for the control and the diabetic control groups, though several bacterial groups overlapped, demonstrating a core microbiota dominated mainly by Firmicutes and Bacteroides. A trend of dysbiosis, characterized by low species richness, was observed in the diabetic rats, albeit not statistically significant. Serum oxidant and anti-oxidant concentrations were not different (P > 0.05) among different treatment groups. No significant effects of supplementations of prebiotic, probiotic, and synbiotic were observed on species richness or clustering pattern of the microbiome.

Serum Antioxidants Are Associated with Serum Reproductive Hormones and Ovulation among Healthy Women

Background: Evidence is growing that the equilibrium between reactive oxygen species and antioxidants plays a vital role in women's reproductive health.Objective: The objective of this study was to evaluate variations in serum antioxidant concentrations across the menstrual cycle and associations between antioxidants and reproductive hormones and anovulation among healthy women.Methods: The BioCycle Study, a prospective cohort, followed 259 women aged 18–44 y for up to 2 menstrual cycles. Serum fat-soluble vitamin and micronutrient (α-tocopherol, γ-tocopherol, retinol, lutein, lycopene, and β-carotene), ascorbic acid, and reproductive hormone concentrations were measured 5–8 times/cycle. We used weighted linear mixed models to assess associations between antioxidants and hormone concentrations, after adjustment for age, race, body mass index, parity, sleep, pain medication use, total energy intake, concurrent hormones, serum cholesterol, F2-isoprostanes, and other antioxidants. Generalized linear models were used to identify associations with anovulation.Results: Serum antioxidant concentrations varied across the menstrual cycle. Retinol and α-tocopherol were associated with higher estradiol [RR: 1.00 pg/mL (95% CI: 0.67, 1.34 pg/mL); RR: 0.02 pg/mL (95% CI: 0.003, 0.03 pg/mL), respectively] and testosterone [RR: 0.61 ng/dL (95% CI: 0.44, 0.78 ng/dL); RR: 0.01 ng/dL (95% CI: 0.001, 0.01 ng/dL), respectively]. Ascorbic acid was associated with higher progesterone (RR: 0.15 ng/mL; 95% CI: 0.05, 0.25 ng/mL) and with lower follicle-stimulating hormone (RR: −0.06 mIU/mL; 95% CI: −0.09, −0.03 mIU/mL). The ratio of α- to γ-tocopherol was associated with an increased risk of anovulation (RR: 1.03; 95% CI: 1.01, 1.06).Conclusions: These findings shed new light on the intricate associations between serum antioxidants and endogenous hormones in healthy premenopausal women and support the hypothesis that concentrations of serum vitamins affect steroidogenesis even after adjustment for oxidative stress.

Oxidant and Antioxidant Status in Pneumonic Goats with Special Reference to Bacterial Etiology

The current investigation was carried out to evaluate oxidative stress serum biomarkers , antioxidant concentrations and isolation the most common etiology of bacterial pneumonia. Thirty goats of different age and sex belonging to private farms in Giza governorate were used in this study .All goats were exposed to complete and comprehensive clinical examination. The animals were divided into two equal groups apparently healthy (15), diseased (15). Blood samples were collected from both groups to determine enzymatic activates of superoxidase dismutase (SOD), glutathione peroxidase (GPX) in erythrocyte haemolysate, catalase (CAT), vitamin C, vitamin E and Albumin, aspartate aminotransaminase (AST), alanine aminotransaminase (ALT), urea and creatinine, as well as nasal swabs were collected for isolation of possible bacteria. The levels of CAT, SOD and GPX were significant higher (p≤0.05), vitamins C, E were significant decrease (p≤0.05), Significant decrease (p≤0.05) in Albumin in pneumonic goats. Of 30 goats’ nasal swabs, 73.3% (22/30) yielded different bacterial isolates. Mannheimia (Pasteurella) haemolytica was the predominant isolates (81.8%; 18/22) and other isolates . It can concluded that pneumonia served to produce oxidative stress in the goat with increased activities of antioxidant enzymes to facing excessive production of free radicals. For healthier status in small ruminant antioxidant supplementation is very important as supportive treatment in diseased cases and preventive aid in healthy cases. Keywords: Oxidative stress, Antioxidant, Vit. C, Bacteria, Pneumonia, goat

Longitudinal association of measures of adiposity with serum antioxidant concentrations in postmenopausal women.

The relationship between obesity and circulating levels of antioxidants is poorly understood. Most studies that have examined the association of adiposity with blood or tissue concentrations of antioxidant micronutrients have been cross-sectional, and few have compared the associations for indices of overall obesity and central obesity. Our aim was to prospectively examine the longitudinal association of body mass index (BMI), waist circumference (WC), waist circumference-height ratio (WCHtR) and waist-hip ratio (WHR) with major serum antioxidants in a population of postmenopausal women. We used a subsample of participants in the Women's Health Initiative aged 50-79 years at entry with available fasting blood samples and anthropometric measurements obtained at multiple time points over 12.8 years of follow-up (N=2672). Blood samples were used to measure α-carotene, β-carotene, β-cryptoxanthin, lutein+zeaxanthin, α-tocopherol, γ-tocopherol and retinol at baseline, and at years 1, 3 and 6. We used mixed-effects linear regression analyses to examine associations between anthropometric measures and serum antioxidants at baseline and over time, controlling for covariates. In longitudinal analyses, carotenoids, and particularly β-carotene, were strongly and inversely associated with BMI, WC and WCHtR and less so with WHR. α-Tocopherol showed a strong positive association with WHR but not with other anthropometric measures, whereas γ-tocopherol was positively and strongly associated with BMI, WC, WCHtR and less so with WHR. Retinol was positively associated with WHR. The inverse association of several carotenoids with anthropometric measures was stronger in never and former smokers compared with current smokers and in women without the metabolic syndrome. The inverse association of carotenoids with obesity measures may reflect reduced micronutrient concentrations owing to inflammation associated with obesity. In the present study, the strongest observed associations between anthropometric variables and micronutrients were an inverse association of WC with serum β-carotene and a positive association of WC with γ-tocopherol.

Association of Total Levels of Serum Antioxidants with Periportal Fibrosis and Intensity of Schistosoma mansoni Infections in Cheretee, North East Ethiopia

Schistosomiasis is only second to malaria in terms of public health importance among parasitic diseases. Hence morbidity and mortality associated with Schistosoma mansoni are mainly the result of periportal fibrosis of the liver. With the objective of evaluating the association of total serum antioxidants and intensity of S. mansoni infection a cross sectional study was conducted from February 2011 to June 2011 involving 414 individuals and 30 controls from S. mansoni non-endemic area. The study groups were selected using systematic random sampling technique and data were collected using a pre-tested clinical questionnaire, ulthersonographic examinations of the liver and serum ferric reducing antioxidant power (FRAP) assays. Prevalence of Schistosoma mansoni infection and periportal fibrosis in Cheretee was 36.72% and 9.42%, respectively. Prevalence of periportal fibrosis and intensity of infection had a sharp rise in the age group 11-20 years, reached its peak in the 21 to 30-year age group, and started to decline thereafter up to >40. Age, sex and intensity of infection were strongly associated with periportal fibrosis development (p<0.05). Mean total serum antioxidant concentrations were significantly lower in study subjects who were from S. mansoni endemic area (96.5 μM/L) compared with healthy participants from Addis Ababa (339.9 μM/L). However, mean total serum antioxidant concentration were not significantly different among PPF positive and negative individuals from S. mansoni endemic area. Finally, further studies are recommended on the cause of this low antioxidant concentration.

Nativity and Serum Concentrations of Antioxidants in Mexican American Children: A Cross-Sectional Study

There is limited research on the effect of immigration on biological markers of nutrition among children of Mexican origin in the United States. The purpose of this cross-sectional study was to examine data from the Third National Health and Nutrition Examination Survey (NHANES III) (1988–1994), on a national and representative sample of 1559 Mexican American children, 4–16 years of age, and assess the associations of country of birth with serum concentrations of carotenoids, vitamin A, and vitamin E. In multiple regression analyses, Mexico-born Mexican American children had significantly higher serum concentrations of α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, vitamin A, and vitamin E than their counterparts who were born in the United States after adjustment for age, sex, poverty income ratio, level of education of family reference person, body mass index, total serum cholesterol, serum cotinine, total energy intake, and vitamin/mineral consumption. Our findings confirm evidence for a negative effect of immigration/acculturation on dietary quality in this population. These findings also suggest that immigrant Mexican families should be encouraged to maintain their consumption of fruits and vegetables. Prospective studies are needed to further assess the effects of immigration/acculturation on diet and other health outcomes in children of Mexican origin and immigrants.

Abstract P348: A Novel Antioxidant Score Independently Predicts CVD Mortality Better than Any Single Antioxidant: Longitudinal Data from the Third National Health and Nutrition Examination Survey (1988-94)

Despite the implication of oxidative stress in CVD development, neither blood levels of nor supplementation with any one individual antioxidant is consistently related to CVD incidence and death. Thus, the relationship between diet-derived antioxidants and CVD remains unclear. However, many analyses consider the predictive value of only a few antioxidant markers in isolation, which may not reflect overall antioxidant status. We developed an antioxidant score and tested the hypothesis that it would be a more robust predictor of CVD death than concentrations of single antioxidants in aging adults. Quintiles of 10 serum antioxidant concentrations (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, vitamins A, C, E, retinyl esters and selenium), collected at baseline from 7094 (weighted N = 58,875,272) adults aged 50+ years enrolled in the Third National Health and Nutrition Examination Survey (1988-1994) were used as predictors in a time-to-death analysis using Cox regression modeling. Forty-two percent (N=3695, weighted to 26189208) of the sample was deceased at 12-18 year follow-up, with 1362 deceased due to CVD. In models adjusted for known demographic, behavioral and biological risk factors, concentration quintiles of the individual antioxidants α-carotene, lycopene, selenium and retinyl ester were significantly associated with CVD death (ps for trend ranged from 0.015 to 0.042, HRs of quintile 1 vs 5 ranged from 1.34 to 1.52). A stepwise regression method was used to identify the best combination of candidate markers, and an antioxidant score was computed using only those 6 markers (vitamins C and E, lycopene, selenium, α and β-carotene). Quintiles of the antioxidant score were also significantly associated with risk of death (p for trend = 0.004, HR for Q1 vs. Q5 = 1.88) and in a more predictive manner than a score using all 10 antioxidants (p for trend = 0.016, HR for Q1 vs. Q5 = 1.69). After controlling for traditional risk factors, an antioxidant score including vitamins C and E, lycopene, selenium, α and β-carotene was more strongly associated with rates of CVD death than individual antioxidants in a large nationally representative sample of aging adults. An antioxidant score may more closely reflect oxidative status than measures of single dietary antioxidants, and therefore be more useful when assessing risk of CVD death.

Correlation of the oxygen radical activity and antioxidants and severity in critically ill surgical patients – study protocol

BackgroundSurgical patients who require an emergent operation commonly have severe sepsis or septic shock, followed by high morbidity and mortality rates.Despite advances in treatment however, no predictable markers are available. In severe sepsis, many pathophysiologic mechanisms are involved in progression to organ failure, and oxygen free radical and antioxidants are known to contribute to this process. Oxygen free radical and antioxidants contribute to progression of organ failure in severe sepsis. In fact, oxygen radical activity has been reported to be correlated with disease severity and prognosis in patients with severe sepsis or septic shock. Accordingly, we aim to assess the usefulness of oxygen free radical and antioxidant concentrations to predict the disease severity and mortality in a cohort of critically ill surgical patients.Methods/DesignThis is a prospective observation study including patient demographic characteristics, clinical information, blood sampling/serum oxygen radical activity, serum antioxidant activity, serum antioxidant concentrations (zinc, selenium and glutamate), disease severity scores, outcomes, lengths of stay in intensive care unit, hospital 30-day mortality.

Recruitment of Nox4 to a Plasma Membrane Scaffold Is Required for Localized Reactive Oxygen Species Generation and Sustained Src Activation in Response to Insulin-like Growth Factor-I

Nox4-derived ROS is increased in response to hyperglycemia and is required for IGF-I-stimulated Src activation. This study was undertaken to determine the mechanism by which Nox4 mediates sustained Src activation. IGF-I stimulated sustained Src activation, which occurred primarily on the SHPS-1 scaffold protein. In vitro oxidation experiments indicated that Nox4-derived ROS was able to oxidize Src when they are in close proximity, and Src oxidation leads to its activation. Therefore we hypothesized that Nox4 recruitment to the plasma membrane scaffold SHPS-1 allowed localized ROS generation to mediate sustained Src oxidation and activation. To determine the mechanism of Nox4 recruitment, we analyzed the role of Grb2, a component of the SHPS-1 signaling complex. We determined that Nox4 Tyr-491 was phosphorylated after IGF-I stimulation and was responsible for Nox4 binding to the SH2 domain of Grb2. Overexpression of a Nox4 mutant, Y491F, prevented Nox4/Grb2 association. Importantly, it also prevented Nox4 recruitment to SHPS-1. The role of Grb2 was confirmed using a Pyk2 Y881F mutant, which blocked Grb2 recruitment to SHPS-1. Cells expressing this mutant had impaired Nox4 recruitment to SHPS-1. IGF-I-stimulated downstream signaling and biological actions were also significantly impaired in Nox4 Y491F-overexpressing cells. Disruption of Nox4 recruitment to SHPS-1 in aorta from diabetic mice inhibited IGF-I-stimulated Src oxidation and activation as well as cell proliferation. These findings provide insight into the mechanism by which localized Nox4-derived ROS regulates the sustained activity of a tyrosine kinase that is critical for mediating signal transduction and biological actions.

The associations between serum antioxidant concentrations and bone mineral density in women aged 50 and over: an analysis of NHANES 2005–6

It has been shown that diets high in antioxidants are associated with high bone mineral density in postmenopausal women. Conversely, some studies suggest that dietary supplements containing antioxidants may have detrimental effects on bone. Serum concentrations of antioxidants can reflect their intakes from both food and supplements. Thus, the objective of our study was to examine the associations between serum concentrations of several antioxidants and femoral neck BMD (FN_BMD) in postmenopausal women aged ≥50 years. We used cross‐sectional data from the NHANES 2005–6. Multiple regression models with adjustments for relevant confounders were used to examine the associations between serum concentrations of vitamins C and E (alpha‐ and gamma‐tocopherol) and alpha and beta‐carotene, and FN_BMD. The study sample included 168 women, with a mean age of 67.5±0.5 years, who were free from diseases and medications that affect bone metabolism, and were fasting &gt;;9 hours prior to examination. In adjusted models, serum concentration of vitamin C had a positive association with FN_BMD (p=0.018), while serum concentration of beta‐carotene had a negative association with FN_BMD (p=0.008). The association between higher serum vitamin C and higher BMD in our study is consistent with findings of other studies. The negative association between serum beta‐carotene and femoral neck BMD needs further investigation.Grant Funding Source: None

Dietary antioxidant capacity is associated with improved serum antioxidant status and decreased serum C-reactive protein and plasma homocysteine concentrations

To investigate the associations of dietary TAC from diet and supplements with serum antioxidant concentrations and serum C-reactive protein (CRP) and plasma total homocysteine (tHcy) in US adults. This was a cross-sectional study. Food consumption data, serum antioxidant levels, and serum CRP and Plasma tHcy concentrations of 4,391 US adults aged ≥19 years in the National Health and Nutrition Examination Survey 2001-2002 were analyzed. The USDA flavonoid and proanthocyanidin databases and dietary supplement data as well as antioxidant capacities of 43 antioxidants were also utilized. Serum CRP and plasma tHcy concentrations were higher in older adults, smokers, and those with lower non-leisure time physical activity levels (P < 0.05). Energy-adjusted daily total antioxidant capacity (TAC) from diet and supplements was positively associated with serum vitamin E and carotenoid concentrations (P < 0.05). Adjusted odds ratio (OR) for plasma tHcy >13 μmol/L significantly decreased across quartiles of TAC from diet and supplements (Q1 = 2.18 (1.56-2.77); Q2 = 1.30 (1.00-2.07); Q3 = 1.34 (0.84-2.28); Q4 = 1.00; P for linear trend <0.001). A negative trend across quartiles of TAC from diet and supplements was also observed in OR for serum CRP ≥3 mg/L (Q1 = 1.26 (0.97-1.70); Q2 = 1.21 (0.91-1.66); Q3 = 0.97 (0.80-1.24); Q4 = 1.00; P for linear trend <0.05). These findings indicated that dietary TAC provided an integrated conceptual tool in assessing serum antioxidants and investigating the associations between antioxidant intake and CVD risk. The implicated applicability of dietary TAC needs further validation in prospective cohort studies.

Fecal Lactic Acid Bacteria Increased in Adolescents Randomized to Whole-Grain but Not Refined-Grain Foods, whereas Inflammatory Cytokine Production Decreased Equally with Both Interventions1–4

The intake of whole-grain (WG) foods by adolescents is reported to be approximately one-third the recommended intake of 48 g/d. This 6-wk randomized interventional study determined the effect of replacing grains within the diet with refined-grain (RG;n= 42) or WG (n= 41) foods/d on gastrointestinal and immune health in adolescents (aged 12.7 μ 0.1 y). A variety of grain-based foods were delivered weekly to participants and their families. Participants were encouraged to eat 3 different kinds of study foods (e.g., bread, cereals, snacks)/d with goals of 0 g/d (RG) and 80 g/d (WG). Stool samples were obtained during the prebaseline and final weeks to measure bifidobacteria and lactic acid bacteria (LAB) using qPCR. Stool frequency was recorded daily. Blood was drawn at baseline and at final visits for immune markers. Across groups, total-grain intake increased by one serving. The intake of WG was similar at baseline (18 μ 3 g) between groups but increased to 60 μ 5 g in the WG group and decreased to 4 μ 1 g in the RG group. Fecal bifidobacteria increased from baseline with both interventions, but LAB increased (P< 0.05) from baseline [2.4 μ 0.2 log10genome equivalents (eq)] to wk 6 (3.0 μ 0.2 log10genome eq) in the WG group but not in the RG group (baseline: 2.9 μ 0.2 log10genome eq; wk 6: 3.0 μ 0.1 log10genome eq). There was no difference in stool frequency, serum antioxidant potential, or in vitro LPS-stimulated mononuclear cell production of inflammatory cytokines between groups. However, across both groups the number of daily stools tended to increase (P= 0.08) by 0.0034 stools/g WG or by 0.2 stools with 60 g WG, mean antioxidant potential increased by 58%, and mean production of TNF-α, IL-1β, and IL-6 decreased by 24, 22, and 42%, respectively, between baseline and wk 6. Overall, incorporating either WG or RG foods increased serum antioxidant concentrations and decreased inflammatory cytokine production; however, WG study foods had more of an effect on aspects of gastrointestinal health.

Serum Antioxidant Concentrations and Metabolic Syndrome Are Associated among U.S. Adolescents in Recent National Surveys1–3

Specific micronutrients, including retinol, retinyl esters, carotenoids [α-carotene, β-carotene (cis+trans), β-cryptoxanthin, lutein+zeaxanthin, and total lycopene], vitamin E, and vitamin C have antiinflammatory and antioxidant effects, properties shown to reduce oxidative stress, a process that accompanies the pathogenesis of many chronic diseases. It is still largely unknown whether they are associated with the occurrence of metabolic syndrome (MetS) in the adolescent U.S. population. MetS was defined by the International Diabetes Federation (IDF) criteria. Other non-MetS outcomes relying on blood measurements were elevated HOMA-IR, C-reactive protein (CRP), and hyperuricemia. We tested associations between serum antioxidants and MetS outcomes among adolescents aged 12–19 y using cross-sectional data from NHANES 2001–2006 (n = 782–4285). IDF MetS prevalence was estimated at 7% among boys and 3% among girls. In adjusted models, adolescents with MetS had consistently lower carotenoid concentrations compared with their counterparts without MetS. Total carotenoids were also inversely related to HOMA-IR and CRP. Vitamin C was inversely related to uric acid level and MetS binary outcome. Retinol+retinyl esters exhibited an inverse relationship with CRP and a positive relationship with uric acid and HOMA-IR as well as MetS binary outcome. Vitamin E had no association with MetS, particularly after controlling for serum cholesterol and TG. In conclusion, among U.S. adolescents, serum carotenoid concentrations were inversely associated with MetS status, HOMA-IR, and CRP, whereas serum vitamin C was inversely related to MetS status and serum uric acid. Vitamin E had no consistent association with MetS, whereas retinol+retinyl esters had a positive relationship with HOMA-IR, uric acid, and MetS, while being inversely related to CRP. These associations need further study.

Serum β-Carotene in Relation to Risk of Prostate Cancer: The Kuopio Ischaemic Heart Disease Risk Factor Study

Results from epidemiologic studies on the association between circulating carotenoid concentrations and the risk of prostate cancer are still inconsistent. We studied whether serum concentrations of carotenoids were associated with the risk of developing prostate cancer. The study population consisted of 997 middle-aged Finnish men (56.1 ± 6.6 yr) in the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) cohort. Serum concentrations of carotenoids were measured by high-performance liquid chromatography. Subjects were classified into tertiles according to their serum concentrations of antioxidants. Relative risks (RRs) were estimated by using the Cox proportional hazard models. During the mean follow-up time of 15 yr, a total of 68 prostate cancer cases occurred. After adjusting for age, examination yr, family history of cancer, BMI, pack-yr of smoking, alcohol consumption, education, physical activity, serum total cholesterol, and serum α-linolenic acid, men in the highest tertile of serum concentrations of β-carotene had 2.3-fold higher risk of prostate cancer as compared to those in the lowest tertile (RR = 2.29, 95% CI: 1.12–4.66; P = 0.023). α-Tocopherol and retinol were not associated with prostate cancer. This prospective study suggests that high-serum β-carotene concentrations may increase the risk of prostate cancer in middle-aged men.

The effect of ischemic preconditioning on redox status during liver resections—randomized controlled trial

Portal clamping during liver resection decreases intraoperative blood loss, but causes ischemic-reperfusion (I-R) injury. Intermittent portal clamping (IPC) and ischemic preconditioning (IP) decreased I-R injury in animal models. Most of the human studies about IP excluded cirrhotic patients, whose liver is more vulnerable to I-R injury. The effect of IP and IPC during extended liver resection was investigated in this randomized controlled trial, with special respect to cirrhotic patients. One hundred sixty patients (100 normal liver, 60 cirrhotic) undergoing major liver resection were randomized to receive IPC (15 min ischemia, 5 min reperfusion), or IP (10 min ischemia, 10 min reperfusion). Serum oxygen-derived free radicals (ODFR) and antioxidant concentrations (preoperative, after reperfusion and 7th postoperative day), such as "conventional" liver tests (preoperative, 1st, 3rd, and 7th postoperative day) were measured. IP resulted in significantly lower peak ODFR, AST, ALT, and bilirubin levels after liver resection than IPC (P < 0.05). The level of serum antioxidants after reperfusion was significantly higher in IP than in IPC groups (P < 0.05). In cirrhotic patients without IP none of these values normalized until the 7th postoperative day. Ischemic preconditioning--especially in patients with liver cirrhosis--is a suitable method to decrease the I-R injury of the liver.