Comparison of serum iron, total iron binding capacity, ferritin, and percent transferrin saturation in nine species of apparently healthy captive lemurs

Lemurs kept in captivity have been reported to be highly prone to accumulate excessive amounts of iron in tissues (hemosiderosis). Diagnosis of the condition is most commonly made during a postmortem examination because an antemortem diagnosis requires a liver biopsy, a procedure that may not be well tolerated by all animals. The lack of a noninvasive method to evaluate iron status in captive lemurs limits investigators' ability to effectively screen animals for the presence of hemosiderosis, and to detect the condition early when treatment protocols are most effective. This study was conducted in an effort to provide data regarding iron analyte values in healthy captive lemurs of multiple species. The relationship of various iron-related metabolites was evaluated in 177 clinically normal lemurs of nine different species. Serum iron (sI), total iron binding capacity (TIBC), and ferritin concentration were measured directly and the percent transferrin saturation (TS) was calculated. Significant differences in various iron metabolites were observed among several species, suggesting that normal reference values for iron metabolites in lemurs may need to be developed on a species by species basis.     

Conflicting effects of BMI and waist circumference on iron status

The association between obesity and iron status has a long history and is still receiving attention. However comparative analysis of the association between general obesity (BMI) and visceral obesity (waist circumference) with iron status has not been extensively researched. The aim of the present study is thus to determine if body mass index and waist circumference have the same correlation with iron status. One thousand one hundred and thirty people (225 men and 905 women) aged 30 years and above participated in this study. Anthropometric parameters, haemoglobin, iron and total iron binding capacity concentrations were measured using standard methods. Percentage transferrin saturation was calculated and ferritin concentrations were measured using an enzyme linked immunosorbent assay. Obese or overweight women had significantly lower iron and transferrin saturation concentration when compared to non-obese women. In contrast, women with high waist circumference had comparable plasma iron and transferrin saturation to women with normal waist circumference. Partial correlation analysis and linear regression analysis showed that BMI is negatively and significantly associated with plasma iron, transferrin saturation, Hb and ferritin concentration, whilst waist circumference is positively but insignificantly associated with plasma iron, transferrin saturation, Hb and ferritin concentration. Binary regression analysis showed that obese or overweight people are more likely to have iron deficiency, whilst those with raised waist circumference are more likely to have iron overload. Multivariate analysis showed that body mass index is negatively and significantly associated with low iron status, while waist circumference is positively and insignificantly associated with iron status. This is supported by a comparison of plasma iron, transferrin saturation and ferritin concentrations in participants with high body mass index and normal waist circumference and participants with normal body mass index and high waist circumference to those participants having normal body mass index and normal waist circumference. The present study suggests that in women body mass index is associated with low plasma iron, transferrin saturation and ferritin concentrations, while waist circumference is associated with high plasma iron, transferrin saturation and ferritin concentrations.     

Ferritin and liver fibrosis among patients with chronic hepatitis C virus infection

IntroductionIn chronic hepatitis C virus (HCV) infection there is increased iron absorption leading to iron overload, a fact that may promote ferritin synthesis. Theoretically, increased ferritin should promote ongoing liver fibrosis but disparate results have been described.ObjectiveWe analyze the behavior of iron metabolism- related variables, comparing them with fibrosis and inflammatory activity in liver biopsy in HCV infected patients.Patients and MethodsWe analyzed among 90 HCV patients subjected to liver biopsy prior to antiviral treatment the relationships of serum levels of iron, ferritin, transferrin, transferrin saturation index (TSI) and total iron binding capacity (TIBC) with liver fibrosis and histological severity, assessed by Metavir-f, Metavir-a and Knodell indices, as well as with liver function, and also compared the aforementioned iron metabolism- related variables with 34 controls.ResultsPatients showed higher values of sideremia (T = 2.04; p = 0.044) and transferrin (T = 2.29; p = 0.004) compared with controls; but not ferritin, that was significantly higher among the 33 patients who also consumed alcohol (Z = 2.05; p = 0.041). Most patients showed a well preserved liver function (86 cases, Child A). Patients with Child B or C showed higher ferritin levels (Z = 2.68; p = 0.007) and TSI (Z = 2.41; p = 0.016), but lower transferrin and TIBC (Z = 3.25; p = 0.001) than Child A patients. Transferrin and TIBC were directly related to albumin (ρ = 0.24; p = 0.026), whereas bilirubin showed direct relationships with iron (ρ = 0.25; p = 0.016), TSI (ρ = 0.39; p < 0.001) and ferritin (ρ = 0.36; p < 0.001). Both ferritin (ρ = −0.22; p = 0.04) and TSI (ρ = −0.25; p = 0.016) were related to platelet count. No relationships were observed between iron variables and Knodell index, but serum iron, serum transferrin, and TSI were directly related to Metavir-f score (ρ = 0.28; p = 0.009, ρ = 0.22; p = 0.044, and ρ = 0.22; p = 0.044, in this order).ConclusionAlterations of iron related variables are relatively subtle in our series of 90 well compensated HCV patients. Serum ferritin was not related to liver fibrosis and increases only when alcoholism co-exists with HCV infection.     

Association of iron metabolism markers,socioeconomic and lifestyle factors with endometriosis: A cross-sectional study

BackgroundEvidence on the link between iron metabolism markers and endometriosis is limited. We aimed to investigate the associations of iron metabolism markers, including serum ferritin level and transferrin saturation, with endometriosis.MethodsThis study involved 6551 participants from the National Health and Nutrition Examination Survey (NHANES). Univariable and multivariable logistic regression analyses were used to examine the linear relationships between iron metabolism markers and endometriosis. Furthermore, restricted cubic splines were used to identify the non-linear dose-response associations.ResultsUnivariable analysis showed that the factors associated with endometriosis included age, race, education level, and smoking status. In multivariable model, compared with lowest quartile, highest quartile of serum ferritin level was positively associated with endometriosis (OR: 2.11, 95% confidence intervals [CI]: 1.31, 3.40, P = 0.004), and third quartile of transferrin saturation positively associated with endometriosis (OR: 1.55, 95% CI: 1.05, 2.29, P = 0.033). The restricted cubic splines showed the non-linear (inverted U-shape) associations between serum ferritin level and transferrin saturation and endometriosis (all P for non-linear＜0.01), indicating that the ORs of endometriosis increased with serum ferritin level and transferrin saturation up to the turning point and thereafter the ORs of endometriosis did not significantly increase with the increasing serum ferritin and transferrin saturation.ConclusionsOur findings suggests that serum ferritin level and transferrin saturation were positively associated with endometriosis. Serum ferritin and transferrin saturation may be an important marker for endometriosis. Future prospective and longitudinal studies are necessary to better understand these findings.     

Non-anemic iron deficiency,oral iron supplementation,and oxidative damage in college-aged females

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.     

Plasma ferritin concentrations: their clinical significance and relevance to patient care.

In healthy persons the plasma ferritin concentration is a sensitive index of the size of body iron stores. It has been successfully applied to large-scale surveys of the iron status of populations. It has also proved useful in the assessment of clinical disorders of iron metabolism. A low plasma ferritin level has a high predictive value for the diagnosis of uncomplicated iron deficiency anemia. It is of less value, however, in anemia associated with infection, chronic inflammatory disorders, liver disease and malignant hematologic diseases, for which a low level indicates iron deficiency and a high level excludes it, but intermediate levels are not diagnostic. Measuring the plasma ferritin concentration is also useful for the detection of excess body iron, particularly in idiopathic hemochromatosis, but again it lacks specificity in the presence of active hepatocellular disease. If iron overload is suspected in these circumstances determination of the iron content of a percutaneous liver biopsy specimen is required. In families with idiopathic hemochromatosis the combined determination of the plasma ferritin concentration and the transferrin saturation is a sufficient screen to identify affected relatives; however, estimation of the hepatic iron concentration is required to establish the diagnosis.     

Haematological values in pregnant women in Port Harcourt, Nigeria II: Serum iron and transferrin, total and unsaturated iron binding capacity and some red cell and platelet indices

Previous studies on the normal values of serum iron, unsaturated iron binding capacity, total iron binding capacity, serum transferrin, percent transferrin saturation, red cell distribution width, and various platelet indices: Platelet count, mean platelet volume, platelet distribution width, plateletcrit and platelet larger cell ratio in pregnant subjects in Nigeria are relatively scanty. Present study aims to determine the values of these parameters in apparently healthy pregnant subjects residing in Port Harcourt south eastern Nigeria; and help establish normal reference ranges of these parameters for the population under reference. Cross sectional prospective study involving 220 female subjects attending for the first time, the ante-natal clinics of a tertiary health care facility in Port Harcourt. Subjects were divided into 73, 75 and 72 subjects in the first, second and third trimester of pregnancy respectively. Serum iron and unsaturated iron binding capacity, red cell distribution width, platelet count and platelet distribution width were determined by automated methods; total iron binding capacity, serum transferrin concentrations, percent transferrin saturation, mean platelet volume and plateletcrit were calculated using appropriate formulas. The values of serum iron, unsaturated iron binding capacity, total iron binding capacity and serum transferrin concentrations were found to show significant variations between the various trimesters of pregnancy. However, while serum iron showed significant decreases during pregnancy; unsaturated iron binding capacity, total iron binding capacity and serum transferrin concentrations were found to show significant increases during pregnancy amongst our subjects. By contrast the values of red cell distribution width, platelet count, mean platelet volume, platelet distribution width, plateletcrit and platelet larger cell ratio did not show any significant differences at the different trimesters of pregnancy in our subjects. The present study reports, for the first time, normative values for these parameters in apparently healthy pregnant subjects in Port Harcourt south eastern Nigeria. Apparently, increases in unsaturated and total iron binding capacity and serum transferrin values seen amongst our subjects with increasing gestation may perhaps be a mechanism to ensure a fetal adequate iron delivery on account of the decreasing serum iron concentration with gestation in our subjects. The study suggests that values of serum transferrin are perhaps a more useful screening tool for iron deficiency anemia during pregnancy amongst our subjects.     

Decreased Serum Hepcidin Concentration Correlates with Brain Iron Deposition in Patients with HBV-Related Cirrhosis

Purpose

Excessive brain iron accumulation contributes to cognitive impairments in hepatitis B virus (HBV)-related cirrhotic patients. The underlying mechanism remains unclear. Hepcidin, a liver-produced, 25-aminoacid peptide, is the major regulator of systemic iron metabolism. Abnormal hepcidin level is a key factor in some body iron accumulation or deficiency disorders, especially in those associated with liver diseases. Our study was aimed to explore the relationship between brain iron content in patients with HBV-related cirrhosis and serum hepcidin level.

Methods

Seventy HBV-related cirrhotic patients and forty age- sex-matched healthy controls were enrolled. Brain iron content was quantified by susceptibility weighted phase imaging technique. Serum hepcidin as well as serum iron, serum transferrin, ferritin, soluble transferrin receptor, total iron binding capacity, and transferrin saturation were tested in thirty cirrhotic patients and nineteen healthy controls. Pearson correlation analysis was performed to investigate correlation between brain iron concentrations and serum hepcidin, or other iron parameters.

Results

Cirrhotic patients had increased brain iron accumulation compared to controls in the left red nuclear, the bilateral substantia nigra, the bilateral thalamus, the right caudate, and the right putamen. Cirrhotic patients had significantly decreased serum hepcidin concentration, as well as lower serum transferring level, lower total iron binding capacity and higher transferrin saturation, compared to controls. Serum hepcidin level negatively correlated with the iron content in the right caudate, while serum ferritin level positively correlated with the iron content in the bilateral putamen in cirrhotic patients.

Conclusions

Decreased serum hepcidin level correlated with excessive iron accumulation in the basal ganglia in HBV-related cirrhotic patients. Our results indicated that systemic iron overload underlined regional brain iron repletion. Serum hepcidin may be a clinical biomarker for brain iron deposition in cirrhotic patients, which may have therapeutic potential.     

The Ratio of sTfR/Ferritin is Associated with the Expression Level of TfR in Rat Bone Marrow Cells After Endurance Exercise

Currently, it is unclear which index of haematological parameters could be used to most easily monitor iron deficiency during endurance training. To address this question, 16 male Wistar rats were randomly assigned to two groups: a sedentary group (n = 8) and an exercised group (n = 8). Initially, animals in the exercise group started running on a treadmill at a rate of 30 m/min, on a 0% grade, for 1 min/session. Running time was gradually increased by 2 min/day. The training plan was one session per day during the initial 2 weeks and two sessions per day during the third to ninth week. At the end of the 9-week experiment, we analysed the blood of the experimental animals for haemoglobin levels, erythrocyte numbers, haematocrit, serum iron levels, total iron binding capacity, transferrin saturation, serum ferritin levels and soluble transferrin receptor (sTfR) levels, and we calculated the ratio of sTfR/ferritin. Erythrocyte numbers, haemoglobin levels and haematocrit values were decreased after 9 weeks of exercise, but sTfR and sTfR/ferritin values were increased (P < 0.01 or P < 0.05). The training regime significantly increased TfR mRNA levels in the bone marrow cells of the exercised rats compared with the sedentary group (1.8 ± 0.5 vs. 1.1 ± 0.2, P < 0.01). These results revealed a significant correlation between TfR levels in the bone marrow cells and the ratio of sTfR/ferritin (r = 0.517; P < 0.01) and sTfR levels (r = 0.206; P < 0.05) in sedentary and exercised rats. In conclusion, we show that sTfR indices and the ratio of sTfR/ferritin could be useful indicators for monitoring iron deficiency during endurance training.     

Impact of daily consumption of iron fortified ready-to-eat cereal and pumpkin seed kernels (Cucurbita pepo) on serum iron in adult women

Iron deficiency, anemia, is the most prevalent nutritional problem in the world today. The objective of this study was to consider the effectiveness of consumption of iron fortified ready-to-eat cereal and pumpkin seed kernels as two sources of dietary iron on status of iron nutrition and response of hematological characteristics of women at reproductive ages. Eight healthy female, single or non pregnant subjects, aged 20-37 y consumed 30 g of iron fortified ready-to-eat cereal (providing 7.1 mg iron/day) plus 30 g of pumpkin seed kernels (providing 4.0 mg iron/day) for four weeks. Blood samples collected on the day 20 of menstrual cycles before and after consumption and indices of iron status such as reticulocyte count, hemoglobin (Hb), hematocrit (Ht), serum ferritin, iron, total iron-binding capacity (TIBC), transferrin and transferrin saturation percent were determined. Better response for iron status was observed after consumption period. The statistical analysis showed a significant difference between the pre and post consumption phase for higher serum iron (60 +/- 22 vs. 85 +/- 23 ug/dl), higher transferrin saturation percent (16.8 +/- 8.0 vs. 25.6 +/- 9.0%), and lower TIBC (367 +/- 31 vs. 339 +/- 31 ug/dl). All individuals had higher serum iron after consumption. A significant positive correlation (r=0.981, p=0.000) between the differences in serum iron levels and differences in transferrin saturation percentages and a significant negative correlation (r=-0.916, p<0.001) between the differences in serum iron levels and differences in TIBC was found, as well. Fortified foods contribute to maintaining optimal nutritional status and minimizing the likelihood of iron insufficiencies and use of fortified ready-to-eat cereals is a common strategy. The results showed that adding another food source of iron such as pumpkin seed kernels improves the iron status. Additional and longer studies using these two food products are recommended to further determine the effect of iron fortification on iron nutrition and status among the target population, and mainly in young children, adolescents, women of reproductive ages and pregnant women.     

Serum indices of body stores of iron in northern fur seals (Callorhinus ursinus) and their relationship to hemochromatosis

Iron storage disease (hemochromatosis) has been reported in many species of both captive and free‐ranging animals. In this study we examined the relationship between this disease and concentrations of iron analytes in aquarium‐held northern fur seals (Callorhinus ursinus). Sera were analyzed for iron, total iron‐binding capacity (TIBC), ferritin, ceruloplasmin, and haptoglobin concentrations in a retrospective study that included samples taken over a 14‐year period. The animals ranged in age from <1 year to an estimated 23 years. Serum ferritin was measured using an enzyme‐linked immunosorbent assay (ELISA) for canine sera. The results from this assay are the first reported for any pinniped. Serum iron concentrations in presumed healthy animals ranged from 37 to 196 µg/dl, and TIBC ranged from 136 to 484 µg/dl. The transferrin saturation percentage differed significantly between male (41%) and female (63%) adult fur seals, as did the ferritin levels (54 ng/ml for males vs. 500 ng/ml for females). There was a trend toward increased serum ferritin and percent transferrin saturation with age, especially in females. The data also showed a relationship between serum iron and transferrin saturation among eight mother–pup pairs, which suggests that pups may develop increased iron levels due to placental transfer of iron and/or transfer of iron through the milk from iron‐overloaded females. Diet was considered as a factor in the development of hemochromatosis in at least three geriatric female northern fur seals, and their diets were analyzed for iron concentrations. On the basis of these results, the diets were altered by replacing a portion of the high‐iron‐content fish (herring) with a lower‐iron‐content item (squid), and discontinuing iron and vitamin C supplementation (via a multivitamin tablet). Sera were analyzed before, and 1 and 4 years after the dietary changes were implemented. Paired t‐tests showed no significant changes in the iron analytes from pre‐ to post‐diet‐change samples, which indicates that it may be too late to affect iron levels by diet alone in older animals with a chronic history of elevated iron levels. Zoo Biol 23:205–218, 2004. © 2004 Wiley‐Liss, Inc.     

Usefulness of the serum ferritin concentration in the detection of iron deficiency in a general hospital.

The efficacy of measuring the transferrin saturation and the serum ferritin concentration to detect iron deficiency was determined under routine conditions in a general hospital. The tests were performed on 100 adult patients who consecutively underwent bone marrow aspiration for the appraisal of a wide range of clinical conditions. The absence of stainable reticuloendothelial iron in smears of the aspirate was used as the benchmark of iron deficiency. Of the 86 patients who were anemic 19 lacked hemosiderin in the bone marrow. The percentage of patients with iron deficiency who were correctly classified by the tests (i.e., the tests'' sensitivity) was 84% for the transferrin saturation and 79% for the serum ferritin concentration, and the percentage of patients free of iron deficiency who were correctly classified by the tests (i.e., the tests'' specificity) was 63% and 96% respectively. The predictive value of an abnormal (positive) result for the detection of iron deficiency was 39% for the transferrin saturation and 83% for the serum ferritin concentration, whereas the predictive value of a normal or high (negative) result for the exclusion of iron deficiency was 93% and 94% respectively. Measurement of the serum ferritin concentration was superior to measurement of the transferrin saturation only in its specificity. The former is of particular value in clinical settings where the prevalence of iron deficiency is low and conditions that increase the serum ferritin concentration out of proportion to the size of the body iron stores are infrequent.     

Body iron is a contributor to oxidative damage of DNA

The transition metal iron is catalytically highly active in vitro, and not surprisingly, body iron has been suggested to promote oxidative stress in vivo. In the current analysis we studied the association of serum ferritin concentration and serum soluble transferrin receptor concentration with daily urinary 8-hydroxydeoxyguanosine excretion, a marker of oxidative stress, in 48 mildly dyslipidemic men in East Finland. In multivariate linear regression analyses allowing for age, smoking, body mass index and physical exercise, serum ferritin concentration predicted the excretion rate at B = 0.17 (95% CI 0.08–0.26, P = 0.001), and serum soluble transferrin receptor to ferritin concentration ratio (TfR/ferritin) predicted the excretion rate at B = ? 0.13 (95% CI ? 0.21 to ? 0.05, P = 0.002). Our data suggest that body iron contributes to excess oxidative stress already at non-iron overload concentrations in these subjects.     

Cord transferrin and ferritin values for erythropoiesis in newborn infants of diabetic mothers

Neonatal polycythemia is a perinatal complication in infants of diabetic mothers. The cord CBC (complete blood counts), serum iron, transferrin and ferritin concentrations were studied in newborn infants of 9 GDM (gestational diabetes), 21 NIDDM (noninsulin-dependent diabetes mellitus), and 8 IDDM (insulin-dependent diabetes mellitus) mothers. The RBC (red blood cell) count, Hb (hemoglobin) and Hct (hematocrit) of these infants were higher than control infants. There was no difference between the serum iron concentration of the infants of each group diabetic mothers and the infants in the control group, but the transferrin concentration was significantly higher and the ferritin was significantly lower in the infants of diabetic mothers than in those of control mothers. There was a significant negative correlation between transferrin and ferritin (r = -0.491 p less than 0.001). Erythropoiesis is considered to be enhanced in the fetuses of diabetic mothers, and the iron needed for erythropoiesis is reportedly transported from the mother to the fetus according to the demands of the fetus, but the iron storage was shown to be reduced in the fetuses of diabetic mothers.     

Diagnostic efficacy of tests for the detection of iron overload in chronic liver disease.

The value of tests for the detection of body iron overload was investigated in 8 aptients with clinically manifest primary hemochromatosis, 12 patients with cirrhosis and iron overload and 20 patients with liver disease and low or normal iron stores. Iron overload was defined as the presence of stainable iron in more than 50% of hepatocytes in a liver biopsy specimen. The percentages of patients with a true-positive (abnormal) or true-negative (normal) result were: serum iron concentration 65%, transferin saturation 85%, serum ferritin concentration 78%, serum ferritin:serum glutamic oxaloacetic transaminase (SGOT) index 78%, percent iron absorption 58%, percent iron absorption in relation to serum ferritin concetration 80% and percent iron absorption in relation to serum ferritin:SGOT index 93%. The calculated predictive value of a normal test result for the exclusion of iron overload in patients with liver disease, a group with an assumed prevalence of iron overload of 10%, was 98% to 99% for transferrin saturation and serum ferritin concentration used alone and 100% for these measures used together; the predictive value of an abnormal result for the diagnosis of iron overload was less than 50% for all of the above measures used alone or in combination. Hence, in patients with an increased serum ferritin concentration or transferrin saturation, or both, determination of the hepatocellular iron content of a specimen from a percutaneous liver biopsy is required for the diagnosis of iron overload.     

The effect of the flavonol rutin on serum and liver iron content in a genetic mouse model of iron overload

The flavonol rutin has been shown to possess antioxidant and iron chelating properties in vitro and in vivo. These dual properties are beneficial as therapeutic options to reduce iron accumulation and the generation of reactive oxygen species (ROS) resultant from excess free iron. The effect of rutin on iron metabolism has been limited to studies performed in wildtype mice either injected or fed high-iron diets. The effect of rutin on iron overload caused by genetic dysregulation of iron homoeostasis has not yet been investigated. In the present study we examined the effect of rutin treatment on tissue iron loading in a genetic mouse model of iron overload, which mirrors the iron loading associated with Type 3 hereditary haemochromatosis patients who have a defect in Transferrin Receptor 2 (TFR2). Male TFR2 knockout (KO) mice were administered rutin via oral gavage for 21 continuous days. Following treatment, iron levels in serum, liver, duodenum and spleen were assessed. In addition, hepatic ferritin protein levels were determined by Western blotting, and expression of iron homoeostasis genes by quantitative real-time PCR. Rutin treatment resulted in a significant reduction in hepatic ferritin protein expression and serum transferrin saturation. In addition, trends towards decreased iron levels in the liver and serum, and increased serum unsaturated iron binding capacity were observed. This is the first study to explore the utility of rutin as a potential iron chelator and therapeutic in an animal model of genetic iron overload.     

Changes in transferrin during the red cell replacement in amphibia

Transferrin, a plasma glycoprotein, carries iron from storage sites to immature erythroid cells for hemoglobin synthesis. The replacement of larval red cells by adult red cells, which occurs during metamorphosis in bullfrogs, requires extensive formation of hemoglobin and new red cells. Large changes in red cell iron storage also occur during the red cell replacement. Both the concentration and the level of iron saturation of plasma transferrin were measured during metamorphosis to determine if there were changes in plasma transferrin which coincided with the changes in red cell iron storage and ferritin content. Plasma transferrin concentrations increased from 0.96 to 2.6 mg/ml during the period when red cell storage iron and ferritin decreased. Plasma iron concentrations also increased when the transferrin concentration increased, suggesting that the additional transferrin may be involved in moving iron from the larval red cell stores. At the end of metamorphosis, the plasma iron concentration decreased to premetamorphic levels but the transferrin concentration remained high, resulting in a decrease in saturation to 18% compared to 45% in the larvae. In addition to differences in iron saturation, adult transferrin had different electrophoretic properties from larval transferrin. The results support the hypotheses that during early ontogeny plasma transferrin and red cell iron storage are coordinated to provide iron for the formation of the first generation of adult red cells and that transferrin may participate in the control of red cell ferritin synthesis.     

Iron status of female collegiate athletes involved in different sports

Iron status was assessed in 70 female athletes aged 18–25 yr participating in collegiate cross-country track, tennis, softball, swimming, soccer, basketball, and gymnastics. No significant differences in mean hemoglobin, hematocrit, serum iron, total iron-binding capacity, transferrin saturation, and ferritin were found among teams. The mean concentrations of each parameter for each of the teams were within the normal ranges. However, several athletes from different sports had suboptimal iron status indexes. Of 17 athletes with a serum ferritin concentration ≤15 μg/L, 8 (4 freshmen, 2 sophomores, 2 unknown) also exhibited low serum iron concentrations (< 60μg/dL) and low transferrin saturation (< 16%). Thirteen (6 freshmen, 3 sophomores, 2 juniors, 2 seniors) of 51 (25%) athletes failed to consume two-thirds of the Recommended Dietary Allowance for iron and exhibited suboptimal serum concentrations of ferritin, iron, and/or transferrin saturation. Of nine athletes taking iron supplements, one exhibited suboptimal iron status. In summary, nonanemic iron depletion was present among female collegiate athletes involved in many different sports and in all years of participation (freshmen, sophomore, junior, and senior athletes). Female athletes should continue to be individually and routinely evaluated for nutritional deficiencies throughout their collegiate athletic careers.