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1.
Relation between anemia resistant to recombinant human erythropoietin (rHuEPO) therapy and the oxidative stress in hemodialysis (HD) patients was investigated. Stable HD patients who had consistent hemoglobin concentrations on a constant dose of rHuEPO were studied. Patients were excluded if there were factors that might affect hemopoiesis or administration of antioxidant supplements. Patients were classified into three groups: High (9000 U/week), Low (1500-4500 U/week) and No rHuEPO group. Thiobarbituric acid reactive substances (TBARS) of sera and erythrocyte were examined. Serum superoxide and hydroxyl radical scavenging activities were measured using electron spin resonance. TBARS in the erythrocyte was higher in High rHuEPO group compared with No rHuEPO group, though the serum TBARS were similar. A diminution of serum hydroxyl radical scavenging activity was observed in High rHuEPO group. Hydroxyl radical signal intensity showed a strong correlation with the serum ferritin in High rHuEPO group, although ferritin concentrations were not different among the 3 groups. Superoxide scavenging activity showed no differences. These results indicate that increased lipid peroxidation in erythrocyte, raised by decreased serum hydroxyl radical scavenging activity, is one cause of rHuEPO resistant anemia. Serum ferritin may be involved in this hydroxyl radical production.  相似文献   

2.
Relation between anemia resistant to recombinant human erythropoietin (rHuEPO) therapy and the oxidative stress in hemodialysis (HD) patients was investigated. Stable HD patients who had consistent hemoglobin concentrations on a constant dose of rHuEPO were studied. Patients were excluded if there were factors that might affect hemopoiesis or administration of antioxidant supplements. Patients were classified into three groups: High (9000 U/week), Low (1500-4500 U/week) and No rHuEPO group. Thiobarbituric acid reactive substances (TBARS) of sera and erythrocyte were examined. Serum superoxide and hydroxyl radical scavenging activities were measured using electron spin resonance. TBARS in the erythrocyte was higher in High rHuEPO group compared with No rHuEPO group, though the serum TBARS were similar. A diminution of serum hydroxyl radical scavenging activity was observed in High rHuEPO group. Hydroxyl radical signal intensity showed a strong correlation with the serum ferritin in High rHuEPO group, although ferritin concentrations were not different among the 3 groups. Superoxide scavenging activity showed no differences. These results indicate that increased lipid peroxidation in erythrocyte, raised by decreased serum hydroxyl radical scavenging activity, is one cause of rHuEPO resistant anemia. Serum ferritin may be involved in this hydroxyl radical production.  相似文献   

3.
Inadequate minerals intake, as well as disruption of some metabolic processes in which microelements are cofactors, are suggested to lead to the development of hypertension. The role of minerals in the pathogenesis of hypertension still remains to be explained. In the present study, we sought to determine associations between serum and hair mineral concentrations and serum lipids and glucose levels. Forty obese hypertensive subjects with insulin resistance and 40 healthy volunteers were recruited in the study. Blood pressure, BMI, and insulin resistance were recorded in all subjects. Levels of lipids, glucose, sodium and potassium, iron, copper, zinc, magnesium, and calcium were assessed in serum. Iron, copper, zinc, magnesium, and calcium were assessed in hair. Dietary intake of the analyzed minerals was estimated. We found distinctly higher concentrations of serum iron and serum and hair calcium as well as markedly lower levels of hair zinc in the hypertensive subjects. The study group manifested also significantly lower daily intake of calcium, magnesium, and iron. We observed a relationship between the concentrations of iron, zinc, and copper in serum and hair and high and low range of cholesterol, triglycerides, and glucose serum levels in the studied patients. Moreover, this study demonstrated significant correlation between serum and hair concentrations of selected minerals and their dietary intake and levels of serum lipids and glucose and blood pressure in the study and the control groups. The obtained results seem to indicate the association between lipid and glucose metabolism and iron, copper, zinc, and calcium concentrations in blood and hair of hypertensive and obese patients with insulin resistance.  相似文献   

4.
The aim of this study was to measure the alterations of copper and iron contents in scalp hair samples of hepatitis A–E patients of both genders, same age group, and socioeconomic status. For comparative study, the scalp hair samples of healthy individuals of the same age and socioeconomic status were collected. The concentrations of copper and iron were measured using an atomic absorption spectrophotometer, after microwave-assisted acid digestion. The validity and accuracy of methodology was checked using a certified reference material. The results of this study showed that the mean values of copper and iron were higher in scalp hair samples of hepatitis patients than those of age-matched control subjects, while the difference was significant in the cases of patients having viral hepatitis B, C, and D as compared to those who have viral hepatitis A and E (p?<?0.001). It was concluded that the overload of copper and iron in the human body may cause lipid peroxidation and eventually damage the hepatic system.  相似文献   

5.
The objective of the study was to determine whether iron and micronutrient status is improved with an increased amount of meat in the diet. To this end, a longitudinal prospective study with infants recruited at 4 mo and followed until 24 mo of age was undertaken. One hundred ninety-eight infants formed the original study cohort; 48 withdrew before the end of the study. Subjects were classified as nonmeat eaters or as mixed (red and white)-meat eaters subgrouped into tertiles depending on the meat content reported in diet diaries. Seven-day weighed food records were recorded at 4, 8, 12, 16, 20, and 24 mo. Blood samples taken at 4, 12, and 24 mo were analyzed for parameters of iron and micronutrient status. Iron intake increased during the first year, thereafter remaining constant. The percentages of subjects with hemoglobin values below 110 g/L were 34.1, 23.1, and 13.4 at 4, 12, and 24 mo, respectively. For parameters of iron status, the number of results below the reference range was determined for each diet group and a significant negative relationship between serum iron and meat intake at 12 mo of age was seen (p<0.023). There was a trend for hemoglobin concentrations to be inversely related to the meat intake, at the same age (p<0.068). No effects on zinc or copper status were seen. We conclude that a weak association between dietary meat and iron/Hb suggests a positive role for red meat. There was no disadvantage to the nonmeat-eating infants with respect to zinc or copper.  相似文献   

6.
The aim of this study was to determine whether women with low iron stores (plasma ferritin 相似文献   

7.
There have been inconsistent reports on the relationship between iron status and coronary artery diseases (CAD), and little data on this relationship in non-Caucasian populations.

We assessed dietary iron by questionnaire and measured serum iron and ferritin levels in 270 Saudi male subjects without established CAD, 130 of whom were angiogram negative. Serum lipid profile, glucose, high sensitivity-C reactive protein (hs-CRP), serum soluble intercellular adhesion molecules-1 (sICAM-1), and caeruloplasmin were measured in all subjects.

The angiogram negative patients, had lower serum ferritin (p<0.05) and iron (p<0.0001) levels than the 140 subjects without reported cardiovascular diseases (CVD). Serum iron correlated with serum triglycerides (p<0.0001) and total cholesterol (p<0.05) levels for this latter group and the groups combined. Serum ferritin correlated with serum total cholesterol and low-density lipoprotein (LDL)-cholesterol in the combined group (p<0.05), and was correlated with blood glucose and serum LDL-cholesterol (p<0.05) in the subjects without reported CVD. After adjustment for confounding variables, serum iron levels remained a significant correlate with total calorie intake and serum triglycerides. Serum ferritin also correlated significantly with cholesterol intake and fasting serum total cholesterol. Dietary iron was significantly related to dietary cholesterol and fiber, age, smoking habits, and serum total cholesterol level.

Hence, indices of iron status were related to several coronary risk factors in the Saudi population.  相似文献   


8.
Currently there are no satisfactory methods for estimating dietary iron absorption (bioavailability) at a population level, but this is essential for deriving dietary reference values using the factorial approach. The aim of this work was to develop a novel approach for estimating dietary iron absorption using a population sample from a sub-section of the UK National Diet and Nutrition Survey (NDNS). Data were analyzed in 873 subjects from the 2000–2001 adult cohort of the NDNS, for whom both dietary intake data and hematological measures (hemoglobin and serum ferritin (SF) concentrations) were available. There were 495 men aged 19–64 y (mean age 42.7±12.1 y) and 378 pre-menopausal women (mean age 35.7±8.2 y). Individual dietary iron requirements were estimated using the Institute of Medicine calculations. A full probability approach was then applied to estimate the prevalence of dietary intakes that were insufficient to meet the needs of the men and women separately, based on their estimated daily iron intake and a series of absorption values ranging from 1–40%. The prevalence of SF concentrations below selected cut-off values (indicating that absorption was not high enough to maintain iron stores) was derived from individual SF concentrations. An estimate of dietary iron absorption required to maintain specified SF values was then calculated by matching the observed prevalence of insufficiency with the prevalence predicted for the series of absorption estimates. Mean daily dietary iron intakes were 13.5 mg for men and 9.8 mg for women. Mean calculated dietary absorption was 8% in men (50th percentile for SF 85 µg/L) and 17% in women (50th percentile for SF 38 µg/L). At a ferritin level of 45 µg/L estimated absorption was similar in men (14%) and women (13%). This new method can be used to calculate dietary iron absorption at a population level using data describing total iron intake and SF concentration.  相似文献   

9.
Our aim was to investigate parameters of iron and copper status and oxidative stress and antioxidant function in women with healthy pregnancy, mild and severe preeclampsia with a view to exploring the possible contribution of these parameters to the aetiology. Thirty healthy, 30 mild preeclamptic and 30 severe preeclamptic pregnant women were included. Serum and placental lipid peroxides, and serum vitamin E and total carotene levels were measured by colorimetric assay. Cholesterol, copper, iron, total iron binding capacity (TIBC), ceruloplasmin and transferrin concentrations were measured by commercially available procedures. Data were analysed statistically using one-way analysis of variance and Pearson correlation test. Logistic regression procedures were used to calculate odds ratios. Lipid peroxides in serum and placental tissue, and iron, copper and ceruloplasmin levels in serum were significantly increased, and transferrin, TIBC, vitamin E/total cholesterol and total carotene/total cholesterol ratios in serum were significantly decreased especially in women with severe preeclampsia. Significant correlations were detected between serum iron and lipid peroxides in serum and placental tissue and between serum iron and vitamin E/total cholesterol in severe preeclamptic pregnancy. Furthermore, there were significant correlations between serum malondialdehyde and ceruloplasmin and vitamin E/total cholesterol in women with severe preeclampsia, and changes in serum and placental lipid peroxides and serum iron concentrations were significantly associated with preeclampsia. In conclusion, ischaemic placental tissue may be a primary source of potentially toxic iron in preeclampsia and the released iron species may contribute to the aetiology and would exacerbate lipid peroxidation and endothelial cell injury, which may be abated by antioxidant supplementation.  相似文献   

10.
Increased lipid peroxidation contributes to diabetic complications and redox-active iron is known to play an important role in catalyzing peroxidation reactions. We aimed to investigate if diabetes affects the capacity of plasma to protect against iron-driven lipid peroxidation and to identify underlying factors. Glycemic control, serum iron, proteins involved in iron homeostasis, plasma iron-binding antioxidant capacity in a liposomal model, and non-transferrin-bound iron were measured in 40 type 1 and 67 type 2 diabetic patients compared to 100 nondiabetic healthy control subjects. Iron-binding antioxidant capacity was significantly lower in the plasma of diabetic subjects (83 +/- 6 and 84 +/- 5% in type 1 and type 2 diabetes versus 88 +/- 6% in control subjects, p < 0.0005). The contribution of transferrin, ceruloplasmin, and albumin concentrations to the iron-binding antioxidant capacity was lost in diabetes (explaining only 4.2 and 6.3% of the variance in type 1 and type 2 diabetes versus 13.9% in control subjects). This observation could not be explained by differences in Tf glycation, lipid, or inflammatory status and was not associated with higher non-transferrin-bound iron levels. Iron-binding antioxidant capacity is decreased in diabetes mellitus.  相似文献   

11.
Serum levels of selenium, copper, and zinc were systematically determined in healthy subjects of the Lisbon population. The sample consisted of 183 blood donors of both genders who were divided into two age groups: 20–44 and 45–70 yr of age; relationships with gender, age, the lipid profile, and tobacco consumption were investigated. In the female group, the intake of oral contraceptives and pregnancy were considered for the youngest women, and hormonal replacement therapy (HRT) was taken into account for the oldest ones. Serum concentrations of these elements were in the same range as those found for populations of other European countries. Differences between genders were observed for the three elements studied, with serum selenium and zinc concentrations higher in men and copper levels higher in women. Age-dependent differences were found for selenium: The oldest subjects (regardless gender) presented the highest concentrations of selenium in serum as further demonstrated by the positive correlation with age. In both pregnant and contraceptive-using women, copper was greatly increased, confirming the influence of estrogen status and/or oral contraceptive intake on increased serum copper levels. However, in postmenopausal women, HRT did not significantly affect serum copper levels. Selenium, copper, and zinc status were not different between normolipidemic and hyperlipidemic subjects for the same gender and age range, but selenium levels tended to increase with hyperlipidemia when considering the whole group of subjects. With respect to the lifestyle, higher serum zinc levels were found in tobacco-consuming men. Albumin serum levels were similar for all considered subgroups, except for the pregnant women, for whom a decrease in this parameter was observed. The present study allowed one to obtain reference values for this healthy group of population, which will serve for a comparative study with groups having pathological conditions, such as cardiovascular disease.  相似文献   

12.
Oxidative damage, as indicated by protein carbonyl and lipid hydroperoxide concentrations, was assessed in the plasma of college-aged females with adequate iron status and with non-anemic iron deficiency before and after eight weeks of iron supplementation. At baseline, the mean serum ferritin, iron, transferrin saturation, and total iron binding capacity of the iron deficient group (n = 13) was significantly different from the iron adequate controls (n = 24). Mean plasma lipid hydroperoxide and protein carbonyl concentrations did not differ between groups at baseline. Following eight weeks of iron supplementation, the mean serum ferritin, iron, and transferrin saturation significantly increased and the total iron binding capacity significantly decreased in the iron deficient group. No significant differences in plasma lipid hydroperoxide or protein carbonyl concentrations were found between groups at the end of the study period. When plasma lipid hydroperoxide and protein carbonyl concentrations of subjects within groups were compared at the start versus at the end of the study, no significant differences were found for either group. Neither non-anemic iron deficiency nor its treatment with oral iron supplements is associated with oxidative damage in the plasma of college-aged females.  相似文献   

13.
Iron status was assessed in a representative sample of 188 adolescents living in a medium-sized city in Poland. Dietary intakes were evaluated using records of diet over a period of seven consecutive days. Subjects were considered to be iron deficient when two or more of the following parameters were abnormal: serum ferritin, transferrin saturation or mean corpuscular haemoglobin concentration. Based on this definition, the prevalence of iron deficiency in the investigated sample of children aged from ten to twelve years was 12.7%. Iron deficiency anaemia was defined using the following criteria: haemoglobin values less than 12.0 g. dl (-1) in girls or less than 12.2 g. dl(-1) in boys, combined with an iron deficiency. With such a definition, the prevalence of iron deficiency anaemia in all subjects was 6.3%. Four boys (3.9%) and six girls (6.8%) were diagnosed as anaemic. The values for Hb in the anaemic boys ranged from 10.9 to 12.2 g. dl (-1) and in anaemic girls from 8.7 to 12.0 g. (-1). It was found that the majority of the individuals studied had a dietary haem-iron intake lower than that recommended. No relationship was found between the level of serum ferritin and total iron and vitamin C dietary intake, but there was positive correlation between serum ferritin and intake of haem iron. A seven-day dietary history questionnaire correctly identified children at risk of iron deficiency anaemia.  相似文献   

14.
Iron-deficiency anemia has been shown to alter body mineral concentrations and activities of iron- and non-iron-containing enzymes, especially those with antioxidant functions. These effects, however, have been less studied in nonanemic iron-depleted individuals. Thus, this study assessed indices of selenium status in 12 college-aged females with adequate iron stores and 15 college-aged females with low iron stores before and after iron therapy. Blood samples were drawn at baseline for both groups and following iron supplementation in the low-iron-stores group. Hematocrit, hemoglobin, and serum ferritin concentrations of the low-iron-stores group were significantly lower than those of the control group. The serum transferrin receptor-to-serum ferritin ratio in the low-iron-stores group was significantly greater than that of the control group. Serum selenium and glutathione peroxidase concentrations of the low-iron-stores group were not significantly different from those of the controls. Iron supplementation significantly increased hemoglobin, hematocrit, and serum ferritin concentrations and significantly decreased the serum transferrin receptor concentration and serum transferrin receptor:serum ferritin ratio in the low-iron-stores group posttreatment compared to pretreatment. Serum selenium and glutathione peroxidase concentrations did not differ significantly from pretreatment to posttreatment in the low-iron-stores group. Results of this study indicate that low iron stores without anemia are not associated with impaired selenium status in college-aged females.  相似文献   

15.
Red cell membrane lipid peroxidation in B and EB thalassemias has been found to increase significantly. The increased iron status of the patients, as revealed by the serum ferritin level, did not have any correlation with lipid peroxidation in either of the groups.  相似文献   

16.
Since moderate hyperhomocysteinemia is an independent risk factor for vascular disease by mean of its oxidant effect and glutathione plays a main role as intracellular redox-regulating agent, we have studied for the first time the total intracellular content of homocysteine in aging. Plasma homocysteine concentration, total intracellular and plasma glutathione, and other related thiol compounds such as cysteine and the glutathione catabolite cysteinglycine were also studied. Forty three healthy elderly subjects and twenty seven healthy young ones were studied. The total intracellular peripheral blood mononuclear cell content was higher for homocysteine, cysteine and cysteinglycine, whereas that of the total glutathione was greatly decreased in elderly people with respect to young ones. Elderly subjects showed significantly higher levels than young ones of total plasma homocysteine and cysteinglycine, but not cysteine, whereas total plasma glutathione levels were increased. In addition, elderly subjects showed significantly decreased plasma vitamin E levels and increased concentrations of serum lipid peroxides measured as TBARS (reaction product of malondialdehyde with thiobarbituric acid). The intracellular glutathione content presented significantly negative correlation with serum TBARS, and intracellular and plasma homocysteine levels. These findings show an increase of homocysteine synthesis associated with aging, which in turn can produce an augmented oxidant effect on endothelium, and an impaired intracellular antioxidant capacity leading to an enhanced lipid peroxidation and decreased total intracellular glutathione content.  相似文献   

17.
Specific recommendations for anemic individuals consist in increasing red meat intake, but the population at large is advised to reduce consumption of red meat and increase that of fish, in order to prevent the risk of developing cardiovascular disease. This study aimed to determine the effects of consuming an oily fish compared to a red meat diet on iron status in women with low iron stores. The study was designed attending the Consolidated Standards of Reporting Trials (CONSORT) statement guidelines. It was a randomised crossover dietary intervention study of two 8-week periods. Twenty-five young women with low iron stores completed the study. Two diets containing a total of 8 portions of fish, meat and poultry per week were designed differing only in their oily fish or red meat content (5 portions per week). At the beginning and the end of each period blood samples were taken and hemoglobin, hematocrit, serum ferritin, serum iron, serum transferrin, serum transferrin receptor-2 and the Zn-protoporphyrin/free-protoporphyrin ratio were determined. Food intake and body weight were monitored. During the oily fish diet, PUFA intake was significantly higher (p=0.010) and iron intake lower (mean±SD, 11.5±3.4 mg/dayvs. 13.9±0.1 mg/day, p=0.008), both diets providing lower mean daily iron intake than recommended for menstruating women. Although there were no significant differences after 16 weeks, serum ferritin moderately decreased and soluble transferrin receptor increased with the oily fish, while changes with the red meat diet were the opposite. In conclusion, an oily fish diet compared to a red meat diet does not decrease iron status after 8 weeks in iron deficient women.  相似文献   

18.
Recent studies have demonstrated that vegetable rich diets have protective effects on the occurrence and prognosis of various cancers. In addition to dietary intakes, ascorbic acid and β-carotene are also taken as supplements. The aim of this study was to assess effects of ascorbic acid, β-carotene and their combinations on human hepatocellular carcinoma cell line HepG2. Ascorbic acid and β-carotene were applied to cells as plasma peak concentrations (70 and 8 μM, respectively) and their half concentrations (35 and 4 μM, respectively) for 24 and 48 h. Genotoxic and cytotoxic effects of ascorbic acid and β-carotene were evaluated by alkali single cell gel electrophoresis (SCGE), acridine orange/ethidium bromide staining patterns of cells (apoptosis and necrosis) and lipid peroxidation (thiobarbituric acid reactive substances, TBARS). Results of the SCGE demonstrated that both ascorbic acid and β-carotene caused DNA damage on HepG2 which were also concordant to increased apoptosis and necrosis of cells. Increased TBARS values also demonstrated increased lipid peroxidation in these cells. Results of the present study demonstrates that when dietary intakes of ascorbic acid and β-carotene and their relevant achievable plasma level concentrations were considered, both ascorbic acid and β-carotene induce genotoxic and cytotoxic damage on HepG2 together with increased oxidative damage in contrast to their protective effect on healthy cells. This may be correlated to oxidative status and balance of ROS in hepatocellular carcinoma cells.  相似文献   

19.
Oxidant stress is one of the factors proposed to be responsible for damaged erythrocytes observed during and after exercise. The impact of exertional oxidant stress after acute exhaustive treadmill running on erythrocyte damage was investigated in sedentary (Sed) and exercise-trained (ET) rats treated with or without antioxidant vitamins C and E. Exhaustive exercise led to statistically significant increments in the levels of thiobarbituric acid-reactive substance (TBARS) and H2O2-induced TBARS in Sed rats and resulted in functional and structural alterations in erythrocytes (plasma hemoglobin concentrations, methemoglobin levels, and rise in osmotic fragility of erythrocytes with decrease in erythrocyte deformability). Administration of antioxidant vitamin for 1 mo before exhaustive exercises prevented lipid peroxidation (TBARS, H2O2-induced TBARS) in Sed rats without any functional or structural alterations in erythrocytes. Parameters indicating erythrocyte lipid peroxidation and deterioration after exhaustive exercise in rats trained regularly with treadmill running for 1 mo were not different from those in Sed controls. Erythrocyte lipid peroxidation (TBARS) increased in exhausted-ET rats compared with ET controls; however, the plasma hemoglobin, methemoglobin levels, and erythrocyte osmotic fragility and deformability did not differ. Exhaustive exercise-induced lipid peroxidation in ET rats on antioxidant vitamin treatment was prevented, whereas functional and structural parameters of erythrocytes were not different from those of the ET controls. We conclude that exertional oxidant stress contributed to erythrocyte deterioration due to exercise in Sed but not in ET rats.  相似文献   

20.
The diabetogenic action of alloxan is believed to involve oxygen free radicals and iron. Incubation of glutathione (GSH) and alloxan with rat liver ferritin resulted in release of ferrous iron as assayed by spectrophotometric detection of ferrous-bathophenanthroline complex formation. Neither GSH nor alloxan alone mediated iron release from ferritin. Superoxide dismutase (SOD) and catalase did not affect initial rates of iron release whereas ceruloplasmin was an effective inhibitor of iron release. The reaction of GSH with alloxan resulted in the formation of the alloxan radical which was detected by ESR spectroscopy and by following the increase in absorbance at 310nm. In both instances, the addition of ferritin resulted in diminished alloxan radical detection. Incubation of GSH, alloxan, and ferritin with phospholipid liposomes also resulted in lipid peroxidation. Lipid peroxidation did not occur in the absence of ferritin. The rates of lipid peroxidation were not affected by the addition of SOD or catalase, but were inhibited by ceruloplasmin. These results suggest that the alloxan radical releases iron from ferritin and indicates that ferritin iron may be involved in alloxan-promoted lipid peroxidation.  相似文献   

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