Oral repletion of iron induces free radical mediated alterations in the gastrointestinal tract of rat

Iron metabolism and ferroptosis: A pathway for understanding preeclampsia

Preeclampsia (PE) is a serious medical condition that poses a significant health risk to women and children worldwide, particularly in the middle- and low-income countries. It is a complex syndrome that occurs as a result of abnormal pregnancy. Hypertension is the most common symptom of PE, with proteinuria and specific organ systems as detrimental targets. PE's pathogenesis is diverse, and its symptoms can overlap with other diseases. In early pregnancy, when the placenta takes over control, oxidative stress may be closely associated with ferroptosis, a type of cell death caused by intracellular iron accumulation. Ferroptosis in the placenta is defined by redox-active iron availability, loss of antioxidant capacity and phospholipids containing polyunsaturated fatty acids (PUFA) oxidation. Recent studies suggest a compelling potential link between ferroptosis and PE. In this article, we comprehensively review the current understanding of PE and discuss one of its emerging underlying mechanisms, the ferroptosis pathway. We also provide perspective and analysis on the implications of this process in the diagnosis, prevention, and treatment of preeclampsia. We aim to bridge the gap between clinicians and basic scientists in understanding this harmful disease and challenge the research community to put more effort into this exciting new area.

Combination of ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry and network pharmacology to reveal the mechanism of Shengyu Decoction for treating anemia

Anemia is a common clinical hematological disease with a high incidence, which seriously affects human health. Shengyu Decoction is often used in the treatment of anemia. However, the pharmacodynamic substance basis and therapeutic mechanism are still unclear, which hinders the comprehensive development and utilization of Shengyu Decoction. In this study, 143 compounds were identified in Shengyu Decoction using high-throughput ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, 24 of which were absorbed into the blood. Taking these blood-entering ingredients as the research object, we found through network pharmacology research that ferulic acid, calycosin, and astragaloside A can act on AKT1, MAPK1, and MAPK14, and play a role in treating anemia through PI3K-Akt signaling pathway and Pathways in anemia. Finally, it was demonstrated that the active compound could bind to the core target with good affinity by molecular docking. The research shows that Shengyu Decoction has multi-component, multi-target, and multi-channel effects in the treatment of anemia, which provides a basis for the development and clinical application of Shengyu Decoction.

Trend of adherence to iron supplementation during pregnancy among Ethiopian women based on Ethiopian demographic and health surveys: A Multivariable decomposition analysis

Background

Iron deficiency is one of the significant factors of anemia during pregnancy. Iron supplementation is the main method of prevention and control of iron deficiency anemia, and its effectiveness depends on adherence to the iron supplementation.

Methods

This study was based on a secondary analysis of 2005, 2011, and 2016 EDHS data. After the data was weighted using sampling weight, 696, 1,282, and 3,096 in 2005, 2011, and 2016 EDHS data, respectively, were used for the final analysis. The data were edited, cleaned, coded, managed, and analyzed using StataCorp version 16 software. A logit-based multivariable decomposition analysis was used to identify variables significantly associated with the change in the adherence level during pregnancy.

Results

Adherence levels increased from 1.1% (95% CI; 0.4, 2.7) in 2005 EDHS to 12.4% (95% CI; 10.9, 14.1) in 2016 EDHS. About 30.9% of the overall change in the adherence level to iron supplement use during pregnancy was due to the difference in women's sociodemographic-related variables. After adjusting for these compositional changes, ~69.1% of the change in the adherence level was because of the difference in the coefficients (behavior-related variables). Among the behavioral characteristics, women's age-group, rich wealth index, and secondary and above-secondary educational status of their husbands had a statistically significant effect on the positive change in the adherence level of pregnant mothers.

Conclusion

The adherence level to iron supplement use during pregnancy has increased significantly over the last decade in Ethiopia. Both the compositional and behavioral characteristics of women play a major role in the increasing trend of adherence levels.

Effects of sugars on the flavor and antioxidant properties of the Maillard reaction products of camellia seed meals

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MRPs were obtained by heating camellia seed meal hydrolysates, and different sugars.

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The ratio of essential amino acids in R-MRPs was increased and the antioxidant activity was the highest.

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MR could improve the flavor and antioxidant activity of camellia seed meal.

In the present study, camellia seed meal Maillard reaction products (MRPs) were prepared using camellia seed meal protein as a raw material. The effects of MR on protein structure and volatile components of camellia seed meal were investigated by fluorescence, UV absorption, infrared spectroscopy, and gas chromatography-mass spectrometry. Not only the change of amino acid content in MRPs, but also the antioxidant capacity of MRPs and the antioxidant capacity after in vitro digestion were determined. Our result showed that the ratio of essential amino acids in R-MRPs was increased and the antioxidant activity was the highest. For the potential of MRPs as flavoring, our sensory evaluation results showed improved flavor and antioxidant activity of camellia seed meal after MR which can be used as flavoring agents at industrial level.

Natural Antioxidants in Anemia Treatment

Anemia, characterized by a decrease of the hemoglobin level in the blood and a reduction in carrying capacity of oxygen, is a major public health problem which affects people of all ages. The methods used to treat anemia are blood transfusion and oral administration of iron-based supplements, but these treatments are associated with a number of side effects, such as nausea, vomiting, constipation, and stomach pain, which limit its long-term use. In addition, oral iron supplements are poorly absorbed in the intestinal tract, due to overexpression of hepcidin, a peptide hormone that plays a central role in iron homeostasis. In this review, we conducted an analysis of the literature on biologically active compounds and plant extracts used in the treatment of various types of anemia. The purpose of this review is to provide up-to-date information on the use of these compounds and plant extracts, in order to explore their therapeutic potential. The advantage of using them is that they are available from natural resources and can be used as main, alternative, or adjuvant therapies in many diseases, such as various types of anemia.

Ameliorating Iron Overload in Intestinal Tissue of Adult Male Rats: Quercetin vs Deferoxamine

OBJECTIVE

The aim of our study is to compare the role of the new natural alternative (Quercetin) with the current iron-chelation therapy (Deferoxamine (DFO)) in the effect of iron overload on small intestinal tissues and to investigate the possible underlying molecular mechanisms of such toxicity.

METHODS

Forty-two adult male albino rats were divided into six groups: control groups, DFO, Quercetin, iron overload, iron overload+DFO, and iron overload+Quercetin groups. Animals received daily intraperitoneal injection of Deferoxamine (125 mg /kg), Quercetin (10 mg/kg), and ferric dextran (200 mg/kg) for 2 weeks.

RESULTS

Iron overloaded group showed significant increase in serum iron, total iron binding capacity (TIBC), transferrin saturation percentage (TS %) hepcidin (HEPC), serum ferritin, nontransferrin bound iron (NTBI), and small intestinal tissues iron levels. Iron overload significantly increased the serum oxidative stress indicator (MDA) and reduced serum total antioxidant capacity (TAC). On the other hand, iron overload increased IL6 and reduced IL10 in small intestinal tissues reflecting inflammatory condition and increased caspase 3 reactivity indicating apoptosis and increased iNOs expressing cell indicting oxidative stress especially in ileum. In addition, it induced small intestinal tissues pathological alterations. The treatment with Quercetin showed nonsignificant differences as compared to treatment with DFO that chelated the serum and tissue iron and improved the oxidative stress and reduced tissue IL6 and increased IL10 and decreased caspase 3 and iNOs expressing cells in small intestinal tissues. Moreover, it ameliorated the iron overload induced pathological alterations.

CONCLUSION

Our study showed the potential role of Quercetin as iron chelator like DFO in case of iron overload induced small intestinal toxicity in adult rats because of its serum and tissue iron chelation, improvement of serum, and small intestinal oxidative stress, ameliorating iron induced intestinal inflammation, apoptosis, and histopathological alterations.

Quercetin modulates iron homeostasis and iNOS expression of splenic macrophages in a rat model of iron deficiency anemia

Iron deficiency anemia is one of the most common micronutrient deficient conditions around the globe with various consequences, including the weakened immune system. Quercetin is widely distributed bioflavonoid; it has been debated for its dual roles in iron regulation. Quercetin-iron interaction in the body is a complex mechanism which has not been completely understood. The present study aimed to investigate the effect of quercetin on iron supplementation in iron deficiency anemia and on iNOS expression in splenic macrophages. The rat model of iron deficiency anemia was induced by feeding low iron diet to weanling rats for 20 days. The animals were then administered with ferrous sulfate, quercetin, and their combination for 30 days. Blood parameters, histopathological analysis, iron storage, CD68, iNOS and SLC40 expression in rat spleen were investigated. Our results showed that quercetin regulated iron absorption, despite SLC40 down-expression, indicating possible alternate route of iron transport, and that quercetin modulated iNOS production in splenic macrophages.

A food synergy approach in a national program to improve the micronutrient status of preschoolers: a randomized control trial protocol

Iron deficiency anemia (IDA) is a significant public health issue in India affecting nearly all vulnerable segments of the population. Causes of IDA include low consumption of iron-rich foods combined with poor iron bioavailability of nonheme iron sources. To date, interventions aimed at correcting IDA focus on increasing iron intake through iron supplementation or fortification strategies. In contrast, dietary diversification is a long-term sustainable approach to improve bioavailable iron intake. In this context, the inclusion of vitamin C-rich fruits in the regular diet has proven to improve iron absorption, but the effect on iron status is inconclusive. Considering the ongoing national program for preschoolers in India, we designed a cluster randomized controlled trial (RCT) to test the hypothesis that inclusion of vitamin C-rich fruit in a regular meal would improve iron absorption and lead to better child iron and micronutrient status, cognitive development, gut health, and growth while reducing morbidity. This paper illustrates a context-specific framework and activities to design and functionalize an open-label, three-arm cluster RCT to test a specific hypothesis. The results of this designed trial should generate evidence to inform policy on the effect of a food-based intervention on iron status.

Effects of micronutrients on placental function: evidence from clinical studies to animal models

Micronutrient deficiencies are common in pregnant women due to low dietary intake and increased requirements for fetal development. Low maternal micronutrient status is associated with a range of pregnancy pathologies involving placental dysfunction, including fetal growth restriction (FGR), small-for-gestational age (SGA), pre-eclampsia and preterm birth. However, clinical trials commonly fail to convincingly demonstrate beneficial effects of supplementation of individual micronutrients, attributed to heterogeneity and insufficient power, potential interactions and lack of mechanistic knowledge of effects on the placenta. We aimed to provide current evidence of relationships between selected micronutrients (vitamin D, vitamin A, iron, folate, vitamin B12) and adverse pregnancy outcomes, combined with understanding of actions on the placenta. Following a systematic literature search, we reviewed data from clinical, in vitro and in vivo studies of micronutrient deficiency and supplementation. Key findings are potential effects of micronutrient deficiencies on placental development and function, leading to impaired fetal growth. Studies in human trophoblast cells and rodent models provide insights into underpinning mechanisms. Interestingly, there is emerging evidence that deficiencies in all micronutrients examined induce a pro-inflammatory state in the placenta, drawing parallels with the inflammation detected in FGR, pre-eclampsia, stillbirth and preterm birth. Beneficial effects of supplementation are apparent in vitro and in animal models and for combined micronutrients in clinical studies. However, greater understanding of the roles of these micronutrients, and insight into their involvement in placental dysfunction, combined with more robust clinical studies, is needed to fully ascertain the potential benefits of supplementation in pregnancy.

Dietary Iron Deficiency and Oversupplementation Increase Intestinal Permeability, Ion Transport, and Inflammation in Pigs

BACKGROUND

Understanding the influence of dietary iron deficiency and dietary iron oversupplementation on intestinal health is important for both animal production and human health.

OBJECTIVE

The aim of this study was to determine whether dietary iron concentration influences intestinal physiology, morphology, and inflammation in the porcine duodenum.

METHODS

Twenty-four male pigs (21 d old) were fed diets containing either 20 mg Fe/kg [low dietary iron (L-Fe)], 120 mg Fe/kg [adequate dietary iron (A-Fe); control], or 520 mg Fe/kg [high dietary iron (H-Fe)] by FeSO4 supplement (dry matter basis). After 32-36 d, the duodenum was harvested from pigs and mounted in Ussing chambers for the measurement of transepithelial electrical resistance (TER), short-circuit current, and (3)H-mannitol permeability. Intestinal morphology and inflammation were assessed by histologic examination, and proinflammatory gene expression was assessed by real-time polymerase chain reaction.

RESULTS

Compared with A-Fe-fed pigs, pigs fed L-Fe diets exhibited reduced TER (by 30%; P < 0.05). Compared with that of A-Fe-fed controls, the paracellular flux of (3)H-mannitol across the duodenal mucosa was higher (P < 0.05) in L-Fe-fed (>100%) and H-Fe-fed (∼4-fold) pigs; the L-Fe-fed and H-Fe-fed groups did not differ significantly from one another. Compared with the L-Fe-fed pigs, the A-Fe-fed and H-Fe-fed pigs had malondialdehyde concentrations 1.4- and 2.5-fold higher in the duodenum and 4.4- and 6.6-fold higher in the liver, respectively (P < 0.05). Neutrophil counts were higher in both the L-Fe-fed (by 3-fold) and H-Fe-fed (by 3.3-fold) groups than in the A-Fe-fed group; the L-Fe-fed and H-Fe-fed groups did not significantly differ from one another. Duodenal mucosal tumor necrosis factor α (TNFA), interleukin (IL) 1β, and IL6 relative gene expression was upregulated by 36%, 28%, and 45%, respectively, in H-Fe pigs (P < 0.05), but not in L-Fe pigs, compared with A-Fe pigs.

CONCLUSION

These data suggest that adequate but not oversupplementation of dietary iron in pigs is required to maintain intestinal barrier health and function.

Oral Administration of Probiotics Inhibits Absorption of the Heavy Metal Cadmium by Protecting the Intestinal Barrier

The heavy metal cadmium (Cd) is an environmental pollutant that causes adverse health effects in humans and animals. Our previous work demonstrated that oral administration of probiotics can significantly inhibit Cd absorption in the intestines of mice, but further evidence is needed to gain insights into the related protection mode. The goal of this study was to evaluate whether probiotics can inhibit Cd absorption through routes other than the Cd binding, with a focus on gut barrier protection. In the in vitro assay, both the intervention and therapy treatments of Lactobacillus plantarum CCFM8610 alleviated Cd-induced cytotoxicity in the human intestinal cell line HT-29 and protected the disruption of tight junctions in the cell monolayers. In a mouse model, probiotics with either good Cd-binding or antioxidative ability increased fecal Cd levels and decreased Cd accumulation in the tissue of Cd-exposed mice. Compared with the Cd-only group, cotreatment with probiotics also reversed the disruption of tight junctions, alleviated inflammation, and decreased the intestinal permeability of mice. L. plantarum CCFM8610, a strain with both good Cd binding and antioxidative abilities, exhibited significantly better protection than the other two strains. These results suggest that along with initial intestinal Cd sequestration, probiotics can inhibit Cd absorption by protecting the intestinal barrier, and the protection is related to the alleviation of Cd-induced oxidative stress. A probiotic with both good Cd-binding and antioxidative capacities can be used as a daily supplement for the prevention of oral Cd exposure.

IMPORTANCE

The heavy metal cadmium (Cd) is an environmental pollutant that causes adverse health effects in humans and animals. For the general population, food and drinking water are the main sources of Cd exposure due to the biomagnification of Cd within the food chain; therefore, the intestinal tract is the first organ that is susceptible to Cd contamination. Moreover, Cd exposure causes the disruption of the intestinal barrier and further induces the amplification of Cd absorption. The present study confirms that, along with initial intestinal Cd sequestration, oral administration of probiotics can inhibit Cd absorption by protecting the intestinal barrier. A probiotic with both good Cd-binding and antioxidative capacities can be used as a daily supplement for the prevention of oral Cd exposure.

Identification of antioxidant peptides of Jinhua ham generated in the products and through the simulated gastrointestinal digestion system

BACKGROUND

The objective of this study was to purify and identify antioxidant peptides present in the extract of Chinese dry-cured Jinhua ham. Jinhua ham extracts were separated into five fractions (A-E) by size-exclusion chromatography. Each fraction was subjected to a simulated gastrointestinal (GI) digestion system and fractions showing strong antioxidant activities were collected and subjected to liquid chromatography combined with tandem mass spectrometry (LC/MS/MS) for further purification and identification.

RESULTS

Using MS/MS analysis, 33 peptides were identified in these fractions. Several key peptides were selected for synthesis and their antioxidant activity determined. The peptide showing strongest DPPH radical scavenging activity was GKFNV, which showed 92.7% antioxidant activity at a concentration of 1 mg mL(-1); the peptide LPGGGHGDL showed the highest hydroxyl radical scavenging activity; and LPGGGT and HA showed strong inhibition activity against erythrocyte hemolysis (about 45%) before digestion. On the other hand, KEER may contribute to Fe(2+) chelating ability in fraction C after GI digestion.

CONCLUSION

Jinhua dry-cured ham seems to be a potential source of antioxidant peptides generated in the products and in GI digestion.

Intermittent oral iron supplementation during pregnancy

BACKGROUND

Anaemia is a frequent condition during pregnancy, particularly among women in low- and middle-income countries. Traditionally, gestational anaemia has been prevented with daily iron supplements throughout pregnancy, but adherence to this regimen due to side effects, interrupted supply of the supplements, and concerns about safety among women with an adequate iron intake, have limited the use of this intervention. Intermittent (i.e. two or three times a week on non-consecutive days) supplementation has been proposed as an alternative to daily supplementation.

OBJECTIVES

To assess the benefits and harms of intermittent supplementation with iron alone or in combination with folic acid or other vitamins and minerals to pregnant women on neonatal and pregnancy outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 July 2015), the WHO International Clinical Trials Registry Platform (ICTRP) (31 July 2015) and contacted relevant organisations for the identification of ongoing and unpublished studies (31 July 2015).

SELECTION CRITERIA

Randomised or quasi-randomised trials.

DATA COLLECTION AND ANALYSIS

We assessed the methodological quality of trials using standard Cochrane criteria. Two review authors independently assessed trial eligibility, extracted data and conducted checks for accuracy.

MAIN RESULTS

This review includes 27 trials from 15 countries, but only 21 trials (with 5490 women) contributed data to the review. All studies compared daily versus intermittent iron supplementation. The methodological quality of included studies was mixed and most had high levels of attrition.The overall assessment of the quality of the evidence for primary infant outcomes was low and for maternal outcomes very low.Of the 21 trials contributing data, three studies provided intermittent iron alone, 14 intermittent iron + folic acid and four intermittent iron plus multiple vitamins and minerals in comparison with the same composition of supplements provided in a daily regimen.Overall, for women receiving any intermittent iron regimen (with or without other vitamins and minerals) compared with a daily regimen there was no clear evidence of differences between groups for any infant primary outcomes: low birthweight (average risk ratio (RR) 0.82; 95% confidence interval (CI) 0.55 to 1.22; participants = 1898; studies = eight; low quality evidence), infant birthweight (mean difference (MD) 5.13 g; 95% CI -29.46 to 39.72; participants = 1939; studies = nine; low quality evidence), premature birth (average RR 1.03; 95% CI 0.76 to 1.39; participants = 1177; studies = five; low quality evidence), or neonatal death (average RR 0.49; 95% CI 0.04 to 5.42; participants = 795; studies = one; very low quality). None of the studies reported congenital anomalies.For maternal outcomes, there was no clear evidence of differences between groups for anaemia at term (average RR 1.22; 95% CI 0.84 to 1.80; participants = 676; studies = four; I² = 10%; very low quality). Women receiving intermittent supplementation had fewer side effects (average RR 0.56; 95% CI 0.37 to 0.84; participants = 1777; studies = 11; I² = 87%; very low quality) and were at lower risk of having high haemoglobin (Hb) concentrations (greater than 130 g/L) during the second or third trimester of pregnancy (average RR 0.53; 95% CI 0.38 to 0.74; participants = 2616; studies = 15; I² = 52%; (this was not a primary outcome)) compared with women receiving daily supplements. There were no significant differences in iron-deficiency anaemia at term between women receiving intermittent or daily iron + folic acid supplementation (average RR 0.71; 95% CI 0.08 to 6.63; participants = 156; studies = one). There were no maternal deaths (six studies) or women with severe anaemia in pregnancy (six studies). None of the studies reported on iron deficiency at term or infections during pregnancy.Most of the studies included in the review (14/21 contributing data) compared intermittent oral iron + folic acid supplementation compared with daily oral iron + folic acid supplementation (4653 women) and findings for this comparison broadly reflect findings for the main comparison (any intermittent versus any daily regimen).Three studies with 464 women examined supplementation with intermittent oral iron alone compared with daily oral iron alone. There were no clear differences between groups for mean birthweight, preterm birth, maternal anaemia or maternal side effects. Other primary outcomes were not reported.Four studies with a combined sample size of 412 women compared intermittent oral iron + vitamins and minerals supplementation with daily oral iron + vitamins and minerals supplementation. Results were not reported for any of the review's infant primary outcomes. One study reported fewer maternal side effects in the intermittent iron group, and two studies that more women were anaemic at term compared with those receiving daily supplementation.Where sufficient data were available for primary outcomes, we set up subgroups to look for possible differences between studies in terms of earlier or later supplementation; women's anaemia status at the start of supplementation; higher and lower weekly doses of iron; and the malarial status of the region in which the trials were conducted. There was no clear effect of these variables on results.

AUTHORS' CONCLUSIONS

This review is the most comprehensive summary of the evidence assessing the benefits and harms of intermittent iron supplementation in pregnant women on haematological and pregnancy outcomes. Findings suggest that intermittent regimens produced similar maternal and infant outcomes as daily supplementation but were associated with fewer side effects and reduced the risk of high levels of Hb in mid and late pregnancy, although the risk of mild anaemia near term was increased. While the quality of the evidence was assessed as low or very low, intermittent may be a feasible alternative to daily iron supplementation among those pregnant women who are not anaemic and have adequate antenatal care.

Evaluation of effects of Maṇḍurabhasma on structural and functional integrity of small intestine in comparison with ferrous sulfate using an experimental model of iron deficiency anemia

Background:

The present study was planned to assess effects of Maṇḍurabhasma (MB) on structural and functional integrity of small intestine using an animal model of iron deficiency anemia (IDA) in rat.

Methods:

IDA was induced by giving iron deficient diet and retro-orbital bloodletting for 21 days in Wistar female rats. Rats (n = 72) were divided into six groups: (i) Control group, (ii) IDA rats, (iii) IDA rats receiving vehicle, (iv) rats receiving ferrous sulfate (40 mg/kg), (vi) rats receiving a low dose (22.5 mg/kg) of MB, (vi) rats receiving a high dose (45 mg/kg) of MB. Treatment was conducted for a period of 21 days followed by an assessment of change in hemoglobin (Hb) levels, lactase levels, lipid peroxidation activity by measuring malondialdehyde (MDA) levels and jejunal morphometry.

Results:

In the present study, the lactase activity was markedly reduced in iron-deficient rats. Our study has demonstrated that intestinal morphology and MDA levels were not altered in the animals with IDA as compared to normal animals. In phase II, improvement in Hb response to ferrous sulfate was accompanied by an improvement in lactase activity. However, it significantly increased MDA levels with derangement of the normal villous structure. Rats receiving a low dose of MB did not have increased MDA levels. It did not alter the jejunal villous structure and improved lactase activity, but hematinic activity was found to be less than that of ferrous sulfate. Rats receiving a high dose of MB showed significantly improved Hb as well as lactase levels. They exhibited damage to the villous structure and increased MDA levels, but the effects were significantly less as compared to ferrous sulfate group.

Conclusion:

Rats receiving a high dose of MB have shown improvement in hematinic and lactase levels comparable to those receiving ferrous sulfate. However, it causes lesser oxidative damage as compared to ferrous sulfate. This is an encouraging finding because it indicates the potential of MB to cause lesser gastrointestinal side effects compared to ferrous sulfate.

Mitochondriogenesis and apoptosis: possible cause of vitamin A-mediated adipose loss in WNIN/Ob-obese rats

BACKGROUND

Previously, we reported that vitamin A-enriched diet (129 mg/kg diet) intake reduces the adiposity development in obese rats of WNIN/Ob strain. Here, we hypothesize that dose lesser than 129 mg of vitamin A/kg diet would also be effective in ameliorating the development of obesity in these rats.

METHODS

Five-month-old male lean and obese rats designated as A & B were divided into four subgroups (I, II, III and IV) consisting of 8 rats from each phenotype and received diets containing 2.6 mg (control group), 26 mg, 52 mg and 129 mg vitamin A/kg diet as retinyl palmitate for 20 weeks. Body composition and morphological analysis of brown adipose tissue (BAT) was analyzed. Expression of uncoupling protein 1 (UCP1), retinoic acid receptor α (RARα) and retinoid X receptor α (RXRα) in BAT and levels of Bcl2 and Bax in epididymal white adipose tissue (eWAT) were determined by immunoblotting.

RESULTS

Vitamin A supplementation to obese rats at doses of 52 and 129 mg/kg diet showed reduced body weight gain and adiposity compared to control diet-fed obese rats receiving 2.6 mg of vitamin A/kg diet. In BAT of obese rats, vitamin A supplementation at doses of 26 and 52 mg of vitamin A/kg diet resulted in increased UCP1 expression with concomitant decrease in RARα and RXRα levels compared to control diet-fed obese rats. Further, transmission electron microscopy study revealed an increase in number of BAT mitochondria of obese rats supplemented with 26 and 52 mg of vitamin A/kg diet. Also, obese rats fed on 52 mg/kg diet resulted in increased apoptosis by altering the ratio of Bcl2 to Bax protein levels in eWAT. Notably, most of these changes were not observed in lean rats fed vitamin A-enriched diets.

CONCLUSION

In conclusion, chronic consumption of 52 mg of vitamin A/kg diet seems to be an effective dose in ameliorating obesity possibly through mitochondriogenesis, UCP1-mediated thermogenesis in BAT and apoptosis in eWAT of obese rats. Therefore, the role of dietary vitamin A in correcting human obesity would be of unquestionable relevance and can only be addressed by future studies.

Iron, oxidative stress and gestational diabetes

Both iron deficiency and hyperglycemia are highly prevalent globally for pregnant women. Iron supplementation is recommended during pregnancy to control iron deficiency. The purposes of the review are to assess the oxidative effects of iron supplementation and the potential relationship between iron nutrition and gestational diabetes. High doses of iron (~relative to 60 mg or more daily for adult humans) can induce lipid peroxidation in vitro and in animal studies. Pharmaceutical doses of iron supplements (e.g., 10× RDA or more for oral supplements or direct iron supplementation via injection or addition to the cell culture medium) for a short or long duration will induce DNA damage. Higher heme-iron intake or iron status measured by various biomarkers, especially serum ferritin, might contribute to greater risk of gestational diabetes, which may be mediated by iron oxidative stress though lipid oxidation and/or DNA damage. However, information is lacking about the effect of low dose iron supplementation (≤60 mg daily) on lipid peroxidation, DNA damage and gestational diabetes. Randomized trials of low-dose iron supplementation (≤60 mg daily) for pregnant women are warranted to test the relationship between iron oxidative stress and insulin resistance/gestational diabetes, especially for iron-replete women.

Investigation of in vitro cytotoxicity of the redox state of ionic iron in neuroblastoma cells

Background:

there is an intimate relation between transition metals and cell homeostasis due to the physiological necessity of metals in vivo. Particularly, iron (ferrous and ferric state) is utilized in many physiological processes of the cell but in excess has been linked with negative role contributing in many neurodegenerative processes.

Objective:

the aim of this study was to investigate which oxidation state of ionic iron (Ferrous (II) versus Ferric (III)) is more toxic to neuronal cells (SHSY₅Y).

Materials and Methods:

The neuroblastoma (SHSY₅Y) cells were exposed to varying concentration of ferric and ferrous iron. Morphological studies using immunofluorescence staining and microscopic analysis as confirmed by intracellular glutathione (GSH) test demonstrated oxidative stress to cells in iron microenvironment. In addition, MTT assay was performed to evaluate the viability and metabolic state of the cells.

Results:

the results showed that ferrous form has significantly higher toxicity compared to the ferric ionic state of higher concentration. In addition, microscopic analysis shows cell fenestration at higher concentrations and swelling at intermediate ferric dosages as demonstrated by atomic force microscopy (AFM). Interestingly, the addition of a differentiation inducing factor, trans-retinoic rcid (RA) retains significant viability and morphological features of the cells irrespective of the ionic state of the iron. AFM images revealed clustered aggregates arising from iron chelation with RA.

Conclusions:

the results indicate that Fe (II) has more toxic effects on cells. In addition, it could be an interesting finding with respect to the antioxidant properties of RA as a chelating agent for the neurodegenerative therapeutics.

Intermittent oral iron supplementation during pregnancy

BACKGROUND

Anaemia is a frequent condition during pregnancy, particularly among women from developing countries who have insufficient iron intake to meet increased iron needs of both the mother and the fetus.Traditionally, gestational anaemia has been prevented with the provision of daily iron supplements throughout pregnancy, but adherence to this regimen due to side effects, interrupted supply of the supplements, and concerns about safety among women with an adequate iron intake, have limited the use of this intervention. Intermittent (i.e. one, two or three times a week on non-consecutive days) supplementation with iron alone or in combination with folic acid or other vitamins and minerals has recently been proposed as an alternative to daily supplementation.

OBJECTIVES

To assess the benefits and harms of intermittent supplementation with iron alone or in combination with folic acid or other vitamins and minerals to pregnant women on neonatal and pregnancy outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (23 March 2012). We also searched the WHO International Clinical Trials Registry Platform (ICTRP) for ongoing studies and contacted relevant organisations for the identification of ongoing and unpublished studies (23 March 2012).

SELECTION CRITERIA

Randomised or quasi-randomised trials.

DATA COLLECTION AND ANALYSIS

We assessed the methodological quality of trials using standard Cochrane criteria. Two review authors independently assessed trial eligibility, extracted data and conducted checks for accuracy.

MAIN RESULTS

This review includes 21 trials from 13 different countries, but only 18 trials (with 4072 women) reported on our outcomes of interest and contributed data to the review. All of these studies compared daily versus intermittent iron supplementation.Three studies provided iron alone, 12 iron+folic acid and three more iron plus multiple vitamins and minerals. Their methodological quality was mixed and most had high levels of attrition. Overall, there was no clear evidence of differences between groups for infant primary outcomes: low birthweight (average risk ratio (RR) 0.96; 95% confidence interval (CI) 0.61 to 1.52, seven studies), infant birthweight (mean difference MD -8.62 g; 95% CI -52.76 g to 35.52 g, eight studies), premature birth (average RR 1.82; 95% CI 0.75 to 4.40, four studies). None of the studies reported neonatal deaths or congenital anomalies.For maternal outcomes, there was no clear evidence of differences between groups for anaemia at term (average RR 1.22; 95% CI 0.84 to 1.80, four studies) and women receiving intermittent supplementation had less side effects (average RR 0.56; 95% CI 0.37 to 0.84, 11 studies) than those receiving daily supplements. Women receiving intermittent supplements were also at lower risk of having high haemoglobin (Hb) concentrations (greater than 130 g/L) during the second or third trimester of pregnancy (average RR 0.48; 95% CI 0.35 to 0.67, 13 studies). There were no significant differences in iron-deficiency anaemia between women receiving intermittent or daily iron+folic acid supplementation (average RR 0.71; 95% CI 0.08 to 6.63, 1 study). There were no maternal deaths (six studies) or women with severe anaemia in pregnancy (six studies). None of the studies reported on iron deficiency at term or infections during pregnancy.Where sufficient data were available for primary outcomes, we set up subgroups to look for possible differences between studies in terms of earlier or later supplementation; women's anaemia status at the start of supplementation; higher and lower weekly doses of iron; and the malarial status of the region in which the trials were conducted. There was no clear effect of these variables on the results of the review.

AUTHORS' CONCLUSIONS

The present systematic review is the most comprehensive summary of the evidence assessing the benefits and harms of intermittent iron supplementation regimens in pregnant women on haematological and pregnancy outcomes. The findings suggest that intermittent iron+folic acid regimens produce similar maternal and infant outcomes at birth as daily supplementation but are associated with fewer side effects. Women receiving daily supplements had increased risk of developing high levels of Hb in mid and late pregnancy but were less likely to present mild anaemia near term. Although the evidence is limited and the quality of the trials was low or very low, intermittent may be a feasible alternative to daily iron supplementation among those pregnant women who are not anaemic and have adequate antenatal care.

Redox biology of the intestine

The intestinal tract, known for its capability for self-renew, represents the first barrier of defence between the organism and its luminal environment. The thiol/disulfide redox systems comprising the glutathione/glutathione disulfide (GSH/GSSG), cysteine/cystine (Cys/CySS) and reduced and oxidized thioredoxin (Trx/TrxSS) redox couples play important roles in preserving tissue redox homeostasis, metabolic functions, and cellular integrity. Control of the thiol-disulfide status at the luminal surface is essential for maintaining mucus fluidity and absorption of nutrients, and protection against chemical-induced oxidant injury. Within intestinal cells, these redox couples preserve an environment that supports physiological processes and orchestrates networks of enzymatic reactions against oxidative stress. In this review, we focus on the intestinal redox and antioxidant systems, their subcellular compartmentation, redox signalling and epithelial turnover, and contribution of luminal microbiota, key aspects that are relevant to understanding redox-dependent processes in gut biology with implications for degenerative digestive disorders, such as inflammation and cancer.

A randomized controlled trial comparing intravenous ferric carboxymaltose with oral iron for treatment of iron deficiency anaemia of non-dialysis-dependent chronic kidney disease patients

BACKGROUND

Iron deficiency is a common cause of anaemia and hyporesponsiveness to erythropoiesis-stimulating agents (ESAs) in non-dialysis-dependent chronic kidney disease (ND-CKD) patients. Current intravenous iron agents cannot be administered in a single high dose because of adverse effects. Ferric carboxymaltose, a non-dextran parenteral iron preparation, can be rapidly administered in high doses.

METHODS

This open-label trial randomized 255 subjects with glomerular filtration rates ≤ 45 mL/min/1.73 m(2), haemoglobin ≤ 11 g/dL, transferrin saturation ≤ 25%, ferritin ≤ 300 ng/mL, and stable ESA dose to either intravenous ferric carboxymaltose 1000 mg over 15 min (with up to two additional doses of 500 mg at 2-week intervals) or oral ferrous sulphate 325 mg thrice daily for a total of 195 mg elemental iron daily for 56 days.

RESULTS

In the modified intent-to-treat population, the proportion of subjects achieving a haemoglobin increase ≥ 1 g/dL at any time was 60.4% with ferric carboxymaltose and 34.7% with oral iron (P < 0.001). At Day 42, mean increase in haemoglobin was 0.95 ± 1.12 vs 0.50 ± 1.23 g/dL (P = 0.005), mean increase in ferritin was 432 ± 189 ng/mL vs 18 ± 45 ng/mL (P < 0.001) and mean increase in transferrin saturation was 13.6 ± 11.9% vs 6.1 ± 8.1% (P < 0.001). Treatment-related adverse events were significantly fewer with ferric carboxymaltose than with oral iron (2.7% and 26.2%, respectively; P < 0.0001).

CONCLUSIONS

We conclude that 1000 mg ferric carboxymaltose can be rapidly administered, is more effective and is better tolerated than oral iron for treatment of iron deficiency in ND-CKD patients.

HFE gene variants modify the association between maternal lead burden and infant birthweight: a prospective birth cohort study in Mexico City, Mexico

BACKGROUND

Neonatal growth is a complex process involving genetic and environmental factors. Polymorphisms in the hemochromatosis (HFE) iron regulatory genes have been shown to modify transport and toxicity of lead which is known to affect birth weight.

METHODS

We investigated the role of HFE C282Y, HFE H63 D, and transferrin (TF) P570 S gene variants in modifying the association of lead and infant birthweight in a cohort of Mexican mother-infant pairs. Subjects were initially recruited between 1994-1995 from three maternity hospitals in Mexico City and 411 infants/565 mothers had archived blood available for genotyping. Multiple linear regression models, stratified by either maternal/infant HFE or TF genotype and then combined with interaction terms, were constructed examining the association of lead and birthweight after controlling for covariates.

RESULTS

3.1%, 16.8% and 17.5% of infants (N=390) and 1.9%, 14.5% and 18.9% of mothers (N=533) carried the HFE C282Y, HFE H63D, and TF P570 S variants, respectively. The presence of infant HFE H63 D variants predicted 110.3 g (95% CI -216.1, -4.6) decreases in birthweight while maternal HFE H63 D variants predicted reductions of 52.0 g (95% CI -147.3 to 43.2). Interaction models suggest that both maternal and infant HFE H63 D genotype may modify tibia lead's effect on infant birthweight in opposing ways. In our interaction models, maternal HFE H63 D variant carriers had a negative association between tibia lead and birthweight.

CONCLUSIONS

These results suggest that the HFE H63 D genotype modifies lead's effects on infant birthweight in a complex fashion that may reflect maternal-fetal interactions with respect to the metabolism and transport of metals.

Supplementation of iron alone and combined with vitamins improves haematological status, erythrocyte membrane fluidity and oxidative stress in anaemic pregnant women

Pregnancy is a condition exhibiting increased susceptibility to oxidative stress, and Fe plays a central role in generating harmful oxygen species. The objective of the present study is to investigate the changes in haematological status, oxidative stress and erythrocyte membrane fluidity in anaemic pregnant women after Fe supplementation with and without combined vitamins. The study was a 2 months double-blind, randomised trial. Pregnant women (n 164) were allocated to four groups: group C was the placebo control group; group I was supplemented daily with 60 mg Fe (ferrous sulphate) daily; group IF was supplemented daily with Fe plus 400 μg folic acid; group IM was supplemented daily with Fe plus 2 mg retinol and 1 mg riboflavin, respectively. After the 2-month trial, Hb significantly increased by 15.8, 17.3 and 21.8 g/l, and ferritin by 2.8, 3.6 and 11.0 μg/l, in the I, IF and IM groups compared with placebo. Polarisation (ρ) and microviscosity (η) decreased significantly in other groups compared with placebo, indicating an increase in membrane fluidity. Significant decreases of ρ and η values compared with group C were 0.033 and 0.959 for group I, 0.037 and 1.074 for group IF and 0.064 and 1.865 for group IM, respectively. In addition, significant increases of glutathione peroxidase activities and decreases of malondialdehyde were shown in all treated groups, as well as increases of plasma retinol and urine riboflavin in group IM. The findings show that supplementation with Fe and particularly in combination with vitamins could improve the haematological status as well as oxidative stress and erythrocyte membrane fluidity.

Iron deficiency in pregnancy

Iron deficiency (ID) and related anaemia (IDA) during pregnancy are highly prevalent worldwide in both developed and developing nations although the causes are often different. At conception, many women lack sufficient iron stores to meet the increased requirements of pregnancy, which are calculated at approximately 1200 mg. Appraisal of iron status in pregnant women is problematic, however the most reliable available diagnostic test is a serum ferritin < 20 µg/L. ID is often associated with other nutritional disorders, and there is frequently a secondary cause or association. A greater oral intake is usually insufficient to meet the increased demands of pregnancy, however regular oral supplements (given either daily or intermittently) can often meet maternal needs and avoid associated neonatal complications of IDA. Over-treatment with iron should be avoided, but intravenous administration is useful when deficiency is discovered late, is severe, or if the woman is intolerant of oral formulations. This paper reviews the current literature, and addresses differences in the prevalence and causes of ID betwen developed and developing nations. It examines gestational iron requirements, distinguishes between ID and IDA, and highlights difficulties in diagnostic testing. Finally, it appraises the evidence for and against different treatment regimens, ranging from food fortification to intravenous iron infusions, according to availability and to need.

Effects and safety of preventive oral iron or iron+folic acid supplementation for women during pregnancy

BACKGROUND

Intake of supplements containing iron or a combination of iron and folic acid by pregnant women may improve maternal health and pregnancy outcomes. Recently, intermittent supplementation regimens have been proposed as alternatives to daily regimens.

OBJECTIVES

To assess the effectiveness and safety of daily and intermittent use of iron or iron+folic acid supplements by pregnant women.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2009) and contacted relevant organisations for the identification of ongoing and unpublished studies.

SELECTION CRITERIA

All randomised or quasi-randomised trials evaluating the effect of supplementation with iron or iron+folic acid during pregnancy.

DATA COLLECTION AND ANALYSIS

We assessed the methodological quality of trials using the standard Cochrane criteria. Two authors independently assessed which trials to include in the review and one author extracted data.

MAIN RESULTS

We included 49 trials, involving 23,200 pregnant women. Overall, the results showed significant heterogeneity across most prespecified outcomes and were analysed assuming random-effects. The trials provided limited information related to clinical maternal and infant outcomes.Overall, daily iron supplementation was associated with increased haemoglobin levels in maternal blood both before and after birth and reduced risk of anaemia at term. These effects did not differ significantly between women receiving intermittent or daily iron or iron+folic acid supplementation. Women who received daily prenatal iron supplementation with or without folic acid were less likely to have iron deficiency at term as defined by current cut-off values than those who received no treatment or placebo. Side effects and haemoconcentration (a haemoglobin level greater than 130 g/L) were more common among women who received daily iron or iron+folic acid supplementation than among those who received no treatment or placebo. The risk of haemoconcentration during the second and third trimester was higher among those on a daily regimen of iron supplementation. The clinical significance of haemoconcentration remains uncertain.

AUTHORS' CONCLUSIONS

Universal prenatal supplementation with iron or iron+folic acid provided either daily or weekly is effective to prevent anaemia and iron deficiency at term. We found no evidence, however, of the significant reduction in substantive maternal and neonatal adverse clinical outcomes (low birthweight, delayed development, preterm birth, infection, postpartum haemorrhage). Associated side effects and particularly haemoconcentration during pregnancy may suggest the need for revising iron doses and schemes of supplementation during pregnancy and adjust preventive iron supplementation recommendations.

Intestinal epithelial cell proteome from wild-type and TNFDeltaARE/WT mice: effect of iron on the development of chronic ileitis

Environmental factors substantially contribute to the development of chronic intestinal inflammation in the genetically susceptible host. Nutritional components like iron may act as pro-oxidative mediators affecting inflammatory processes and cell stress mechanisms. To better characterize effects of dietary iron on epithelial cell responses under the pathological conditions of chronic intestinal inflammation, we characterized the protein expression profile (proteome) in primary intestinal epithelial cells (IEC) from iron-adequate and low-iron fed wild-type (WT) and TNFDeltaARE/WT mice. We performed all possible comparisons between the 4 groups according to genotype or diet. Histological analysis of iron-adequate fed TNFDeltaARE/WT mice (approximately 0.54 mg of iron/day) revealed severe ileal inflammation with a histopathology score of 8.3+/-0.91 (score range from 0-12). Interestingly, low-iron fed mice (approximately 0.03 mg of iron/day) were almost completely protected from the development of inflammatory tissue destruction (histopathology score of 2.30+/-0.73). In total, we identified 74 target proteins with significantly altered steady state expression levels in primary IEC using 2D-gel electrophoresis (2D SDS-PAGE) and peptide mass fingerprinting via MALDI-TOF mass spectrometry (MS). Interestingly, the overlap between the comparison of iron-adequate fed WT and TNFDeltaARE/WT mice (inflamed conditions) and the comparison between the iron-adequate and iron-low fed TNFDeltaARE/WT mice (absence of inflammation) revealed 4 contrarily regulated proteins including aconitase 2, catalase, intelectin 1 and fumarylacetoacetate hydrolase (FAH). These proteins are associated with energy homeostasis, host defense, oxidative and endoplasmic reticulum (ER) stress responses. In conclusion, the iron-low diet affected the epithelial cell proteome and inhibited the development of chronic intestinal inflammation, suggesting a critical role for nutritional factors in the pathogenesis of IBD.

Role of oxidative stress while controlling iron deficiency anemia during pregnancy - Indian scenario

Iron Deficiency anemia ranks 9(th) among 26 diseases with highest burden. Asia bears 71% of this global burden. Adverse maternal and birth outcome associated with hemoglobin status renders the issue worth attention. Indian scenario has worsened over the period despite continuous international and national efforts. This indicates some lacunae in the approach and strategies applied. Various reports state that even with maximum effort to increase outreach and monitoring for adherence to Iron schedule, consumer's compliance remains abysmally low. Recent studies has pointed out biological basis of side effects (gastrointestinal complains and systemic events) as raised oxidative stress for which iron is the key catalyst. Up till now the only target of research has been to raise hemoglobin of pregnant women above 11gm/dl. With the reports of pregnancy specific morbidities i.e. hemorrhage and septicemia with low hemoglobin, eclampsia, small for gestation age, gestational diabetes with higher ranges of hemoglobin, alarm is raised to define optimum range. Use of oxidative stress as biochemical marker with different doses and schedules has been defined because India lack information for its own population upon oxidative stress status when iron is supplemented as per current guidelines. Studies done in India and abroad have defined that too much and too less, both may raise oxidative stress and studies of this sort may provide biochemical scale for optimization. This review therefore has evaluated currently available Indian research and reports to understand the need of future research area. Important findings from other countries have been incorporated for comparison.

Iron status in women with and without gestational diabetes mellitus

OBJECTIVE

Gestational diabetes mellitus (GDM) affects approximately 7% of all pregnancies. Pregnancy, mostly because of the mitochondria-rich placenta, is a condition that favors oxidative stress. A transitional metal, especially iron, which is particularly abundant in the placenta, is important in the production of free radicals. Also, studies have shown that free radicals have a role in GDM. As there are little data about iron status in GDM, this study was performed to compare iron status in GDM and control group.

RESEARCH DESIGN AND METHODS

In this case-control study, 34 women with diagnosed GDM were compared with 34 non-GDM women in the control group at 24-28 weeks of pregnancy in terms of iron status, including ferritin, serum iron, total iron-binding capacity (TIBC), hemoglobin (Hb), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH).

RESULTS

In this study, concentration of serum ferritin, iron, transferrin saturation and hemoglobin, MCV, and MCH was significantly higher in the GDM group and TIBC was significantly lower in this group (P<.05). No significant association was observed with the other variables including familial history of diabetes and GDM.

CONCLUSION

Our findings indicate an association between increased iron status and GDM. The role of iron excess from iron supplementation in the pathogenesis of GDM needs to be examined.

Availability and toxicity of Fe(II) and Fe(III) in Caco-2 cells

The objective of the present study was to compare the toxicity and availability of Fe(II) and Fe(III) to Caco-2 cells. Cellular damage was studied by measuring cell proliferation and lactate dehydrogenase (LDH) release. The activities of two major antioxidative enzymes [superoxide dismutase (SOD) and glutathione peroxidase (GPx)] and differentiation marker (alkaline phosphatase) were determined after the cells were exposed to different levels of iron salts. The cellular iron concentration was investigated to evaluate iron bioavailability. The results show that iron uptake of the cells treated with Fe(II) is significantly higher than that of the cells treated with Fe(III) (P<0.05). Fe(II) at a concentration >1.5 mmol/L was found to be more effective in reducing cellular viability than Fe(III). LDH release investigation suggests that Fe(II) can reduce stability of the cell membrane. The activities of SOD and GPx of the cells treated with Fe(II) were higher than those of the cells treated with Fe(III), although both of them increased with raising iron supply levels. The results indicate that both Fe(II) and Fe(III) could reduce the cellular antioxidase gene expression at high levels.

Reducing, radical scavenging, and chelation properties of in vitro digests of alcalase-treated zein hydrolysate

The objective of the study was to assess the antioxidant potential of alcalase-treated zein hydrolysate (ZH) during a two-stage (1 h of pepsin --> 0.5-2 h of pancreatin, 37 degrees C) in vitro digestion. Sephadex gel filtration and high-performance size exclusion chromatography were used to separate ZH into fractions. The amino acid composition, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(+*)) and 1,1-diphenyl-2-picrylhydrazyl (DPPH*) free radical scavenging activity, reducing power, and Cu (2+) chelation ability were tested to determine the antioxidant efficacy of ZH. Results showed that in vitro digests of ZH contained up to 16.5% free amino acids, with short peptides (<500 Da) making up the rest of the mass. The ABTS(+*) scavenging activity of ZH was decreased by 27% (P<0.05) after pepsin treatment but was fully recovered upon subsequent pancreatin digestion, while the DPPH* scavenging activity of ZH was substantially less than ABTS(+*) scavenging activity and showed a 7-fold reduction following pancreatin treatment. The reducing power of ZH increased 2-fold (P<0.05) following pancreatin digestion when compared with nondigested ZH. The ability of ZH to sequester Cu (2+) was reduced by pepsin digestion but was reestablished following pancreatin treatment. The antioxidant activity demonstrated by in vitro digests of ZH (1-8 mg/mL) was comparable to or exceeded (P<0.05) that of 0.1 mg/mL of ascorbic acid or BHA. The results suggested that dietary zein alcalase hydrolysate may have the benefit to promote the health of the human digestive tract.

Concurrent repletion of iron and zinc reduces intestinal oxidative damage in iron- and zinc-deficient rats

AIM: To understand the interactions between iron and zinc during absorption in iron- and zinc-deficient rats, and their consequences on intestinal oxidant-antioxidant balance.

METHODS: Twenty-four weanling Wistar-Kyoto rats fed an iron- and zinc-deficient diet (< 6.5 mg Fe and 4.0 mg Zn/kg diet) for 4 wk were randomly divided into three groups (n = 8, each) and orally gavaged with 4 mg iron, 3.3 mg zinc, or 4 mg iron + 3.3 mg zinc for 2 wk. On the last day of repletion, 3 h before the animals were sacrificed, they received either 37 mBq of ⁵⁵Fe or ⁶⁵Zn, to study their localization in the intestine, using microautoradiography. Hemoglobin, iron and zinc content in plasma and liver were measured as indicators of iron and zinc status. Duodenal sections were used for immunochemical staining of ferritin and metallothionein. Duodenal homogenates (mitochondrial and cytosolic fractions), were used to assess aconitase activity, oxidative stress, functional integrity and the response of antioxidant enzymes.

RESULTS: Concurrent repletion of iron- and zinc-deficient rats showed reduced localization of these minerals compared to rats that were teated with iron or zinc alone; these data provide evidence for antagonistic interactions. This resulted in reduced formation of lipid and protein oxidation products and better functional integrity of the intestinal mucosa. Further, combined repletion lowered iron-associated aconitase activity and ferritin expression, but significantly elevated metallothionein and glutathione levels in the intestinal mucosa. The mechanism of interactions during combined supplementation and its subsequent effects appeared to be due to modulation of cytosolic aconitase, which in turn influenced the labile iron pool and metallothionein levels, and hence reduced intestinal oxidative damage.

CONCLUSION: Concurrent administration of iron and zinc corrects iron and zinc deficiency, and also reduces the intestinal oxidative damage associated with iron supplementation.

Weekly iron as a safe alternative to daily supplementation for nonanemic pregnant women

BACKGROUND

We undertook this study to compare the effectiveness and safety of antenatal daily and weekly supplementation with iron, folic acid, and vitamin B(12) in healthy, pregnant women who were not anemic at gestational week 20.

METHODS

Women with singleton pregnancies and blood hemoglobin (Hb) >115 g/L at gestational week 20 (equivalent to 105 g/L at sea level) were randomly assigned to two groups, one consuming one tablet containing 60 mg iron, 200 mug folic acid and 1 mug vitamin B(12) daily (DS, n = 56); the other consuming two tablets once weekly (WS, n = 60). Blood Hb and serum ferritin concentrations were measured every 4 weeks from weeks 20 to 36, and pregnancy outcomes were evaluated.

RESULTS

Mild anemia and hypoferritinemia throughout pregnancy occurred less frequently in DS than WS. None of the 116 women had Hb concentrations <103 g/L at any evaluation point. In contrast, hemoconcentration (Hb >145 g/L) from gestational week 28 onwards occurred in 11% in DS and 2% in WS. We observed ex post facto that hemoconcentration at gestational week 28 was associated with a significantly higher relative risk of low birth weight (RR 6.23, 95% CI 1.46-26.57) and premature delivery (RR 7.78, 95% CI 1.45-24.74).

CONCLUSIONS

In women who were nonanemic at gestational week 20, both schemes (DS and WS) prevented the occurrence of Hb levels <100 g/L. DS women had a higher incidence of hemoconcentration. Hemoconcentration was associated with increased risk of low birth weight and premature delivery.

Effects of routine oral iron supplementation with or without folic acid for women during pregnancy

BACKGROUND

It has been suggested that routine intake of supplements containing iron or combination of iron and folic acid during pregnancy improves maternal health and pregnancy outcomes.

OBJECTIVES

To assess the efficacy, effectiveness and safety of routine antenatal daily or intermittent iron supplementation with or without folic acid during pregnancy on the health of mothers and newborns.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (June 2005). Additionally, we contacted relevant organizations for the identification of ongoing and unpublished studies.

SELECTION CRITERIA

All randomised or quasi-randomised trials evaluating the effect of routine supplementation with iron or combination of iron and folic acid during pregnancy.

DATA COLLECTION AND ANALYSIS

We assessed trials for methodological quality using the standard Cochrane criteria. Two authors independently assessed the trials for inclusion and one author extracted data. We collected information on randomisation method, allocation concealment, blinding and loss to follow up. The primary outcomes included maternal and infant clinical and laboratory outcomes.

MAIN RESULTS

Forty trials, involving 12706 women, were included in the review. Overall, the results showed significant heterogeneity across most prespecified outcomes. Heterogeneity could not be explained by standard sensitivity analyses including quality assessment; therefore, all results were analysed assuming random-effects. Very limited information related to clinical maternal and infant outcomes was available in the included trials. The data suggest that daily antenatal iron supplementation increases haemoglobin levels in maternal blood both antenatally and postnatally. It is difficult to quantify this increase due to significant heterogeneity between the studies. Women who receive daily antenatal iron supplementation are less likely to have iron deficiency and iron-deficiency anaemia at term as defined by current cut-off values. Side-effects and haemoconcentration are more common in women who receive daily iron supplementation. No differences were evident between daily and weekly supplementation with regards to gestational anaemia; haemoconcentration during pregnancy appears less frequent with the weekly regimen. The clinical significance of hemoconcentration defined as haemoglobin greater than 130 g/L remains uncertain.

AUTHORS' CONCLUSIONS

Further studies are needed to assess the effects of routine antenatal supplementation with iron or a combination of iron and folic acid on clinically important maternal and infant outcomes.

Effect of daily versus twice weekly long-term iron supplementation on iron absorption and status in iron-deficient women: A stable isotope study

OBJECTIVES

This work aims at studying the effect of daily versus twice weekly long-term Fe supplementation on Fe absorption and status in Fe-deficient women.

DESIGN AND METHODS

The study design is a randomized controlled open study carried out in the Internal Medicine Department, CHU de Clermont-Ferrand, France. Twenty-four young women participated in this study and were randomized into two groups: Group 1 received 50 mg Fe daily, and group 2 received 50 mg Fe twice weekly for 3 months. On day 10 (D10) and on day 90 (D90) of Fe supplementation, blood samples were obtained, and women received orally about 5 mg of 57Fe, and blood was sampled at different times over 24 h. The 57Fe absorption was evaluated by calculating the areas under the curves (AUC). Fe and oxidative stress status were also assessed.

RESULTS

57Fe absorption was similar in both groups on D10 but was greatly decreased in Group 1 and remained high in Group 2 on D90. Fe status was more improved in Group 1 than in Group 2. Oxidative stress status remained statistically unchanged.

CONCLUSIONS

Our study shows that daily Fe supplementation is able to correct an Fe deficiency much more than twice weekly Fe supplementation in young women.

Iron Supplementation in Renal Anemia

Iron-deficiency frequently develops in patients with chronic kidney disease who are treated with recombinant human erythropoietin (rHuEPO). It results in reduced effectiveness of anemia therapy; patients may fail to reach hemoglobin targets or may require excessively large doses of rHuEPO. It has been recognized widely that iron management, monitoring for iron deficiency, and effective iron supplementation forms a core component of anemia therapy. This review discusses the physiology of iron balance, derangements in iron balance in chronic kidney disease (CKD), and the diagnosis and treatment of iron deficiency in patients treated with rHuEPO.

Gene expression in human small intestinal mucosa in vivo is mediated by iron-induced oxidative stress

Iron-induced oxidative stress in the small intestine may alter gene expression in the intestinal mucosa. The present study aimed to determine which genes are mediated by an iron-induced oxidative challenge in the human small intestine. Eight healthy volunteers [22 yr(SD2)] were tested on two separate occasions in a randomized crossover design. After duodenal tissue sampling by gastroduodenoscopy, a perfusion catheter was inserted orogastrically to perfuse a 40-cm segment of the proximal small intestine with saline and, subsequently, with either 80 or 400 mg of iron as ferrous gluconate. After the intestinal perfusion, a second duodenal tissue sample was obtained. Thiobarbituric acid-reactive substances, an indicator of lipid peroxidation, in intestinal fluid samples increased significantly and dose dependently at 30 min after the start of perfusion with 80 or 400 mg of iron, respectively ( P < 0.001). During the perfusion with 400 mg of iron, the increase in thiobarbituric acid-reactive substances was accompanied by a significant, momentary rise in trolox equivalent antioxidant capacity, an indicator of total antioxidant capacity ( P < 0.05). The expression of 89 gene reporters was significantly altered by both iron interventions. Functional mapping showed that both iron dosages mediated six distinct processes. Three of those processes involved G-protein receptor coupled pathways. The other processes were associated with cell cycle, complement activation, and calcium channels. Iron administration in the small intestine induced dose-dependent lipid peroxidation and a momentary antioxidant response in the lumen, mediated the expression of at least 89 individual gene reporters, and affected at least six biological processes.

Modulation of aconitase, metallothionein, and oxidative stress in zinc-deficient rat intestine during zinc and iron repletion

Potential interactions between zinc and iron during absorption and its functional consequences on intestinal oxidative damage and antioxidant status were studied using the zinc-deficient rat as a model. Zinc depletion produced mild-moderate iron deficiency in addition to zinc deficiency, which could be corrected by repletion with iron and zinc. The localization and intensity of both iron and zinc in the intestinal mucosa showed a pronounced decrease in the presence of the other metal, indicating negative interactions. Zinc-deficient intestine exposed to iron alone exhibited elevated peroxidative damage and compromised functional integrity, despite increased expression of ferritin. Inclusion of zinc significantly reduced the damage and improved the functional integrity, accompanied by decreased expression of ferritin. Decreased expression of ferritin in the presence of zinc was consistent with reduced aconitase activity, suggesting its modulation by zinc. Further, inclusion of iron along with zinc was associated with induction of ferritin and metallothionein in tune with the amount of iron and zinc localized in the intestinal mucosa, respectively. These results suggest that zinc and iron interact negatively with cytosolic aconitase, but prove beneficial in reducing the oxidative stress, apart from improving functional integrity and iron/zinc status.

Antioxidant activity of sugar–lysine Maillard reaction products in cell free and cell culture systems

Model Maillard reaction (MR) products (MRPs) employing lysine with an aldohexose (e.g., glucose), ketohexose (e.g., fructose), and aldopentose (e.g., ribose) sugars were generated (e.g., pH 9.0; over 2h heating at 120 degrees ) and fractionated with ethanol into low (LMW) and high (HMW) molecular weight fractions. Characteristically different temporal patterns of fluorescence and ultraviolet/visible absorption spectra were obtained from the three distinct sugar-lysine MRPs, and corresponded to different yields of total and dialyzable carbon, indicating that relative reaction rates and degree of polymerization favored the Rib-Lys MRP, compared to Glu-Lys and Fru-Lys MRPs, respectively (p<0.05). Further characterization of antioxidant activity of the sugar specific-lysine MRPs in chemical (e.g., hydrophobic (1,1,-diphenyl-2-picryl-hydrazyl radical (DPPH) and hydrophilic (Fenton reaction-induced hydroxyl radical) in vitro scavenging assays showed that Rib-Lys HMW MRPs had the highest (p<0.05) affinity to scavenge free radicals. All sugar-Lys MRPs, however, displayed similar protection of cultured Caco-2 cells from exposure to H(2)O(2)-, 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH)-, ferrous (Fe(2+))-, and cupric (Cu(2+))-induced cytotoxicity, evaluated both from redox (e.g., MTT response) and cell membrane integrity (e.g., LDH secretion). HMW-MRPs exhibited stronger (p<0.05) antioxidant activity to scavenge hydroxyl and DPPH radicals, and a greater (p<0.05) protective effect against both Fe(2+)- and Cu(2+)-induced cytotoxicity in Caco-2 cells than corresponding LMW-MRPs. We conclude that HMW MRPs possess affective antioxidant protection against oxidizable substrates; however, the degree of polymerization of this product, characteristic to the source of monosaccharide used in the reaction, is not a distinguishable factor for this bioactivity.

A protective role for zinc on intestinal peroxidative damage during oral iron repletion

Oral iron-supplementation is a general practice to correct iron deficiency anemia. Exposure of iron-deficient intestine to large doses of iron is known to induce oxidative damage, leading to loss of functional integrity, and reduced mucosal cell turnover. Conditioning of intestine with anti-oxidants during iron administration was shown to suppress iron-induced oxidative damage. Zinc is known to protect cells from peroxidative damage by inducing metallothionein and maintaining the sulfhydryl group stability. Nevertheless, co-administration of iron and zinc may antagonize each other with respect to absorption. In the present study, we show that combined supplementation of iron and zinc though marginally inhibits iron uptake significantly attenuates the oxidative stress by induction of metallothionein and elevating the levels of GSH. Further, presence of zinc in situ reduced the iron-induced hydroxyl radical production in the intestinal mucosa, as assessed by EPR spectroscopy. These results strongly suggest a protective role for zinc on iron-induced oxidative stress, which might have implications in anemia control programs.