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Antigua Guatemala, Guatemala

Orozco M.N.,Center for the Studies of Sensory Impairment | Solomons N.W.,Center for the Studies of Sensory Impairment | Schumann K.,TU Munich | Friel J.K.,University of Manitoba | De Montenegro A.L.M.,University of the Valley of Guatemala
Journal of Nutrition | Year: 2010

Prophylactic doses of 120 mg of iron (Fe) are commonly used to prevent Fe-deficiency anemia in vulnerable populations, especially in developing countries. Evidence shows that residual Fe in the large bowel may alter the normal antioxidant capacity of the fecal stream. Our objective was to evaluate the effect of dietary antioxidants from the Carotino Tocotrienol-Carotene Mixed Concentrate (CTCMC) on the depletion of fecal antioxidant capacity by oral Fe supplementation. In total, 17 healthy male adults participated in the 2 phases of the study, 5 in the pilot study and 12 in the definitive intervention trial. Participants received different treatments, separated by washout periods. These included: 120 mg Fe; 120 mg Fe and refined palm oil (FeOil); and 120 mg Fe in refined palm oil combined with 1 of 2 dosages (0.4 g and 0.8 g) of CTCMC/5 mL of refined palm oil (CTCB and CTCA treatments, respectively). Fecal samples were collected and analyzed to quantify the products of hydroxyl radical attack on salicylic acid (2,5 dihydroxybenzoic acid, 2,3-dihydrobenzoic acid, and catechol) at baseline and after active supplementation. Fe supplementation in either form (Fe or FeOil treatments) increased the concentrations of hydroxylated compounds in fecal samples. The production of hydroxylated compounds was significantly lower in treatments CTCB and CTCA than in the FeOil reference. Baseline antioxidant capacity state was virtually restored with dietary carotenoids and tocotrienols from the CTCMC. In conclusion, dietary antioxidants can reverse the depletion of fecal antioxidant capacity induced by oral Fe supplements. © 2010 American Society for Nutrition. Source


Soto-Mendez M.J.,Center for the Studies of Sensory Impairment | Aguilera C.M.,University of Granada | Campana-Martin L.,University of Granada | Martin-Laguna V.,University of Granada | And 3 more authors.
American Journal of Clinical Nutrition | Year: 2015

Background: Researchers have increasingly sought noninvasive methods to determine health and nutritional status in humans. Easy and painless to collect, human urine is a source of noninvasive biomarkers. Objective: We aimed to explore the relation between systemic oxidative stress biomarkers excreted in urine and urinary osmolality (Uosm). Design: The current trial was a descriptive, cross-sectional study. We collected seventy-eight samples of 24-h urine in preschoolers who were attending daycare centers in the Western Highlands province of Quetzaltenango, Guatemala. After we measured the total urine volume (Uvol), the aliquot was stored for the later determination of Uosm as a hydration biomarker and to measure 15-isoprostane F2t (F2-Iso) and 8-hydroxydeoxyguanosine (8-OHdG) as biomarkers of cellular oxidation with the use of ELISA assay kits in Spain. Descriptive statistics and linear [Spearman rank-order (rs)] and nonlinear (goodness-of-fit) correlations were performed. Results: Twenty-four hour Uvols ranged from 65 to 1670 mL, whereas the Uosm varied between 115 and 1102 mOsm/kg. With respect to oxidative biomarkers, the 24-h urinary output of F2-Iso and 8-OHdG had median values of 748 and 2793 ng/d, respectively. The Uvol correlated inversely and significantly with the concentrations of both oxidative biomarkers (F2-Iso rs = 20.603, P < 0.001; 8-OHdG rs = 20.433, P < 0.001), whereas the Uosm was correlated in a direct manner (F2-Iso rs = 0.541, P < 0.001; 8-OHdG rs = 0.782, P < 0.001) when analyzed as a concentration. Associations were weaker when they were analyzed as the total 24-h production. Conclusions: Preschool children from the Western Highlands of Guatemala show strong correlations between hydration status measured through the use of Uosm and biomarkers of oxidative stress in urine. Thus, a relatively superior hydration status is associated with a quantitative reduction in urinary excretion of systemic oxidation products. This trial was registered at clinicaltrials.gov as NCT02203890. © 2015 American Society for Nutrition. Source


Orozco M.N.,Center for the Studies of Sensory Impairment | Solomons N.W.,Center for the Studies of Sensory Impairment | Arriaga C.,Center for the Studies of Sensory Impairment | Hernandez L.,Center for the Studies of Sensory Impairment | And 3 more authors.
Pure and Applied Chemistry | Year: 2012

Among the factors associated with the risk of colorectal cancer and other large bowel diseases are gender, with women having lower incidence than men, and free-radical mediated oxidation. Dietary fiber has been attributed a protective role in human gastro - intestinal health. The main aim of this study was to determine the degree of association between dietary fiber consumption and fecal free-radical production in healthy rural and urban Guatemalan women, moreover, to look for associations between gender and fecal reactive oxidative species (ROS) basal production, a marker of in situ colonic free-radical-based oxidation. For this purpose, we assessed the dietary fiber consumption, using two 24-h recalls, in urban and rural females, and compared the baseline data, i.e., of iron-supplementfree periods, in three previous studies. Two of these trials quantified the fecal ROS generation as total hydroxylated products resulting from free-radical attack on salicylic acid along with residual non-heme iron content in stool samples from 27 Fe-replete men. The third study assessed the same variables in 20 rural and 20 urban women, all consuming their respective habitual diets. The average fiber consumption for females was more than double in the rural group than in the urban population. As for the average ROS responses, a 2.5-fold difference was observed between men and women, with men having the higher concentrations of total hydroxylated products. This difference was sex-linked, unaffected by statistically significant differences in dietary fiber intake, nor by different concentrations of residual fecal non-heme iron between rural and urban women. The difference in background ROS production between men and women suggests a gender-related influence on intraintestinal oxidation that may protect women from harmful effects of dietary oxidants, such as iron. © 2011 IUPAC, Publication date (Web): 29 December 2011. Source


Soto-Mendez M.J.,Center for the Studies of Sensory Impairment | Romero-Abal M.E.,Center for the Studies of Sensory Impairment | Aguilera C.M.,University of Granada | Rico M.C.,University of Granada | And 3 more authors.
PLoS ONE | Year: 2015

Background: Undernutrition and inflammation are related in many ways; for instance, non-hygienic environments are associated with both poor growth and immunostimulation in children. Objective: To describe any existing interaction among different inflammation biomarkers measured in the distinct anatomical compartments of whole blood, feces, plasma and saliva. Methods: In this descriptive, cross-sectional study, samples of whole blood, feces, plasma and saliva were collected on the 8th and last week of observation among 87 attendees (42 girls and 45 boys) of 3 daycare centers offering a common 40-day rotating menu in Guatemala's Western Highlands. Analyses included white blood cell count (WBC), fecal calprotectin, and plasmatic and salivary cytokines including IL-1B, IL-6, IL-8, IL-10 and TNF-α. Associations were assessed using Spearman rank-order and goodness-of-fit correlations, as indicated, followed by backwards-elimination multiple regression analyses to determine predictor variables for IL-10 in both anatomical compartments. Results: Of a total of 66 cross-tabulations in the Spearman hemi-matrix, 22 (33%) were significantly associated. All 10 paired associations among the salivary cytokines had a significant r value, whereas 7 of 10 possible associations among plasma cytokines were significant. Associations across anatomical compartments, however, were rarely significant. IL-10 in both biological fluids were higher than corresponding reference values. When a multiple regression model was run in order to determine independent predictors for IL-10 in each anatomical compartment separately, IL-6, IL-8 and TNF-α emerged as predictors in plasma (r2 = 0.514) and IL-1B, IL-8 and TNF-α remained as independent predictors in saliva (r2 = 0.762). Significant cross-interactions were seen with WBC, but not with fecal calprotectin. Conclusion: Interactions ranged from robust within the same anatomical compartment to limited to nil across distinct anatomical compartments. The prominence of the anti-inflammatory cytokine, IL-10, in both plasma and saliva is consistent with its counter-regulatory role facing a broad front of elevated pro-inflammatory cytokines in the same compartment. © 2015 Soto-Méndez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Source


Orozco M.N.,Center for the Studies of Sensory Impairment | Arriaga C.,Center for the Studies of Sensory Impairment | Solomons N.W.,Center for the Studies of Sensory Impairment | Schmann K.,TU Munich
Annals of Nutrition and Metabolism | Year: 2012

Background: In any context of iron supplementation in the prenatal prophylaxis or therapeutic dosage range, a large amount will remain unabsorbed and pass through the intestinal tract into the colonic digesta possibly causing increased oxidation. Aim: To compare the generation of fecal reactive oxygen species (ROS) in situ after daily consumption of 100 mg of elemental iron in three frequently used forms of iron supplements. Methods: Ten healthy, iron-repleted adult males were investigated before and during supplementation with three oral iron compounds: 100 mg of oral iron were given as ferrous sulfate, Na Fe-EDTA and iron polymaltose for 6 days to each subject in an individually stratified sequence. Stool samples were collected and analyzed for iron content and the in situ generation of fecal ROS. Results: Significant increases in fecal ROS generation were observed during oral iron supplementation. No statistical differences were seen in either residual concentrations of non-heme iron in stool or the level of fecal ROS generation between the three Fe compounds. There was, however, a significant association between the iron concentration in the stool and ROS generation. Conclusion: In spite of the differences in their chemical characteristics, none of the three distinct iron complexes reduced oxidative stress in the intestinal lumen. © 2012 S. Karger AG, Basel. Source

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