The effect of Gypsophila saponins in the diet on mineral status and plasma cholesterol concentration in the rat

1. Immature, male Wistar rats were allocated to one of six groups and caged individually. The first group was given a semi-synthetic diet containing 38 mg iron and 55 mg zinc/kg (basal group). The second and third groups were given a diet containing 10 mg Zn and 12 mg Fe/kg respectively (low-Zn and low-Fe groups). Groups four, five and six were given similar diets containing 20 g Gypsophila saponins/kg. After 21 d the Fe and Zn status of the rats was estimated and plasma cholesterol concentration determined. 2. Measurements of whole blood haemoglobin concentration, packed cell volume and liver Fe stores indicated that rats in the basal + saponin and low-Fe + saponin groups had a significantly reduced Fe status when compared with their controls. Rats in the low-Zn + saponin group also showed a trend toward reduced Fe stores. 3. Zn status, as judged by femur Zn concentration, was not adversely affected by the inclusion of Gypsophila saponins in the diet. 4. Consumption of the saponins resulted in a significant reduction in blood cholesterol concentration, with rats in both the low-Fe groups having significantly lower concentrations than their basal and low-Zn counterparts. 5. In view of suggestions that the consumption of saponins should be encouraged because of their ability to lower blood cholesterol, possible effects on Fe metabolism should be investigated further, particularly with respect to the levels and sources of saponin in the human diet.     

The influence of previous iron intake on the estimation of bioavailability of Fe from a test meal given to rats

Iron retention and its subsequent distribution from 3 g 59Fe extrinsically-labelled wholewheat four in rats given a low (8 micrograms Fe/g)- or high (566 micrograms Fe/g)-Fe diet during the previous 3 d was measured (Expt 1). The mean (with SE) proportion of Fe retained from wholewheat flour was 0.46 (0.04) in the group given the low-Fe diet and 0.15 (0.01) in the group given the high-Fe diet (P less than 0.001). There was no difference in distribution of absorbed 59Fe in the tissues examined. The procedure was repeated in rats given diets containing a range of Fe concentrations, groups 1-6 respectively: 8, 77, 136, 334, 566, 1270 micrograms Fe/g (Expt 2). The mean (with SE) proportions of Fe retained in groups 1-6 respectively were 0.60 (0.02), 0.34 (0.02), 0.30 (0.02), 0.20 (0.20), 0.17 (0.02), 0.09 (0.01). Regression analysis showed that Fe retention was a function of the logarithm of the Fe concentration of the diet consumed before the test meal (R -0.997, P less than 0.0001) where Fe retained (microgram) = 95 -28 log10 Fe concentration of diet. Rats were given a low-, medium- or high-Fe diet (8, 136 or 1270 micrograms Fe/g respectively) for 1 or 2 d instead of 3 d before measuring Fe retention from 3 g wholewheat flour (Expt 3). The mean (with SE) proportions of Fe retained in rats given the low-, medium- or high-Fe diets for 1 d were 0.45 (0.02), 0.25 (0.02) and 0.13 (0.01) (P less than 0.001) and for 2 d 0.47 (0.03), 0.31 (0.03) and 0.18 (0.02) (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of prolonged dietary supplementation with guar gum on subsequent iron absorption and retention in rats

The effect of prolonged consumption of guar gum on iron absorption and Fe status was investigated in rats. Experiments with closed loops of duodenum, isolated in situ, were designed to reveal changes in the short-term regulation of duodenal Fe uptake, induced by challenge with low- and high-Fe meals. In separate experiments, the effect of guar gum on the capacity of intact rats to maintain Fe status and to absorb Fe from a test-meal was investigated. Male Wistar rats were given either a control, semi-synthetic diet (C) for 21 d or a similar diet containing 100 g guar gum (G)/kg for 27 d. Both diets contained 36 mg Fe/kg. Two subgroups were then challenged with meals containing low-Fe (8 mg/kg) or high-Fe (566 mg/kg), while a third subgroup received a meal of the control diet (36 mg Fe/kg). At intervals of 12, 36, 60 and 84 h after the dietary challenge, the uptake of [59Fe]ferric citrate was measured using closed duodenal loops in situ. All G-supplemented animals absorbed less Fe than their C-fed counterparts. Within group C, animals given the high-Fe challenge had lower absorptions 12, 36 and 60 h later, compared with those given the maintenance diet, whilst those given the low-Fe meal showed much increased uptake 12 and 36 h later. The latter effect was virtually abolished by guar gum. In the second experiment, male Wistar rats were fed on the C or G diets containing 8, 15, 20, 26 or 36 mg Fe/kg for approximately 10 weeks ad lib.(ABSTRACT TRUNCATED AT 250 WORDS)     

Proline-rich proteins moderate the inhibitory effect of tea on iron absorption in rats

Tea inhibits iron absorption in studies in which tea is given with radiolabeled iron to humans as a single dose. Our objective was to test the hypothesis that proline-rich proteins (PRPs) may act as a defense against this effect by forming complexes with tannins, thereby preventing them from inhibiting iron absorption. Two studies were conducted. In study 1, rats were given test solutions containing (59)FeCl(3) in water, tea, or tea + gelatin (T/G). In study 2, the rats were divided into 3 groups and assigned to one of 3 nutritionally complete diets: control, tea (5 g tea tannin/kg diet), or T/G (5 g tea tannin + 60 g gelatin/kg diet). Rats were fed the respective diets for 5 d and then given a single (59)Fe-labeled meal of the diet. Iron absorption was measured by whole-body retention of the (59)Fe over a 2-wk period. Iron absorption in study 1 was lower in the tea group (24 +/- 9.6%, P < 0.05) than in the T/G (42 +/- 19.4%) or water groups (50 +/- 7.5%). In study 2, iron absorption did not differ among the groups. Rats fed the tea diet had dramatic hypertrophy of the parotid salivary glands. Adding gelatin as a proxy for salivary PRPs to the tea eliminated the inhibitory effect of tea on iron absorption. The results suggest that PRPs, whether from salivary glands or diet, can protect against the inhibition of iron absorption by tea.     

Mineral metabolism of rats fed moderate levels of various aluminum compounds for short periods of time

The effects of ingesting moderate levels of aluminum (5-272 micrograms Al/g diet) were assessed in two short-term (18-d) studies with rats. Rats were fed diets that contained no added aluminum or aluminum lactate, aluminum palmitate, aluminum phosphate or aluminum hydroxide in either reagent grade or desiccated gel forms. The average concentrations of aluminum in the tibias of rats fed 261-272 micrograms Al/g diet were 13.0-15.6 micrograms Al/g fresh weight, while those of control animals were 1.0-1.9 micrograms Al/g fresh weight. Rats fed aluminum accumulated less aluminum in their kidneys and brains than in their tibias. In study 1, animals fed aluminum hydroxide tended to accumulate more aluminum in tissues, i.e., brain, than animals fed the other aluminum compounds. In study 2 the type of aluminum hydroxide fed did not affect the accumulation of aluminum in tissues but rats fed 206 micrograms Al/g diet accumulated less aluminum in their tibias and more aluminum in their kidneys than rats fed 261 and 268 micrograms Al/g diet. Ingestion of these moderate doses of aluminum had no effects on tissue levels of calcium, magnesium and iron of rats and had only small effects on tissue levels of phosphorus, zinc and copper.     

Nickel influences iron metabolism through physiologic, pharmacologic and toxicologic mechanisms in the rat

A study involving three experiments was done to ascertain whether the beneficial effect of nickel on hematopoiesis in moderately iron-deficient rats was due to physiologic and/or pharmacologic mechanisms. Female Sprague-Dawley rats were fed nickel supplements ranging from 0 to 100 micrograms/g in iron-low (15 micrograms Fe3+/g), iron-adequate (65 micrograms Fe3+/g), or iron-luxuriant (100 micrograms Fe3+/g) diets. The basal diet contained from 2 ng (experiment 3) to 36 ng (experiment 1) of nickel/g. At 10 weeks, both nickel deficiency and toxicity (100 micrograms/g diet) tended to depress hematopoiesis and markedly altered femur and liver trace element content in marginally iron-deficient rats. The alterations included elevated copper, iron and nickel, and depressed calcium and manganese in femurs. The pharmacologic action of nickel was indicated by the finding that high dietary nickel (5, 10, 20 or 50 micrograms/g) apparently stimulated hematopoiesis in marginally iron-deprived rats to a greater extent than dietary levels of nickel (0.1, 0.5 or 1.0 microgram/g) considered adequate for nutritional needs. High dietary nickel also elevated the iron content in liver of marginally iron-adequate rats. The findings indicate that nickel influences iron metabolism at physiologic, pharmacologic and toxic levels of intake. They also indicate that many previously reported signs of nickel deprivation, including effects on hematopoiesis, may have been misinterpreted and might be manifestations of pharmacologic actions of nickel.     

Iron, copper and zinc metabolism of rats fed various levels and types of tea

The effects of tea and components in tea on mineral metabolism were investigated in a series of studies. In studies A and B weanling rats were fed diets containing various levels (0, 0.35, 1.17 or 3.50%) of a commercially prepared instant tea and diets containing 0 or 1.17% catechin. In study C anemic rats were fed diets containing 0 or 2.31% desiccated green or black tea infusions for 23 d. In study D rats were fed a diet containing 2.31% desiccated black tea infusions for 16 d, were fed the tea-containing diet in a single meal labeled with 59Fe or were given black tea infusions as their sole fluids. Rats fed diets containing 2.31% green or black tea or given fluid tea had elevated hematocrits but experienced minimal changes in tissue iron levels or in iron absorption; this is counter to conclusions from studies in which iron absorption was monitored indirectly. Ingestion of instant or black tea consistently elevated liver copper levels; this may be part of the mechanism by which hematological variables were affected. Although the green tea contained significant amounts of aluminum, rats fed the tea did not accumulate aluminum in their bones.     

Iron, zinc and copper interactions: chronic versus acute responses of rats

Several methodologies were evaluated to study iron, zinc and copper interactions. In three studies, rats were fed diets containing adequate levels of iron (33-35 micrograms Fe/g diet) and zinc (15-25 micrograms Zn/g diet) and diets with excessive levels of zinc (2441-2470 micrograms Zn/g diet) or iron (1408-3042 micrograms Fe/g diet). Consumption of excess iron for several weeks or in one test meal did not alter tissue levels of zinc or apparent absorption of 65Zn. In contrast rats fed excess zinc throughout the three studies had depressed hematocrits and serum copper levels, apparently absorbed 59Fe less efficiently and retained less 59Fe in livers and tibias than control animals. Nutritional status with regard to iron or zinc, not just the intakes of iron and zinc, also influenced the interactions between zinc and iron. Rats fed excess iron for several weeks retained less 65Zn from a test meal in their tibias than rats fed excessive iron in only the test meal. Although chronic ingestion of excess zinc depressed apparent absorption of 59Fe from a test meal, the ingestion of one test meal with excess zinc did not. Investigators studying nutrient interactions should not rely solely on studies in which unadjusted humans or animals are given a single dose of test substances because acute responses do not reflect all the changes induced by chronic feeding.     

Further studies in rats on the influence of previous iron intake on the estimation of bioavailability of Fe

Iron retention from 3 g wholewheat flour was measured in male Wistar rats previously given one high-Fe or control diet meal 12, 24, 36, 48 or 60 h before the test meal (Expt 1). The control diet was given at all other times. The procedure was then repeated in rats given one high- or low-Fe meal 12, 24, 36 or 48 h before the test meal (Expt 2). There was a significant difference between groups given a high- or medium-Fe meal at 12, 24, 36 h (P less than 0.001) and 48 h (P less than 0.05) but not at 60 h. In the second experiment, there was a significant difference between groups given a high- or low-Fe meal at 12, 24 or 36 h but no difference when given the two diets 48 h before the test meal. The high-Fe meal depressed and the low-Fe meal enhanced subsequent 59Fe retention: the effects were greatest at 12 h and diminished as the time interval between the high- or low-Fe meal and the test meal increased. The estimated mean time for the absorptive capacity of the mucosal cells to return to equilibrium was 54.0 (SEM 7.6) h. Male Wistar rats were given high-, control or low-Fe diets for either 3 d or 28 d before an in vivo investigation in which the luminal loss of 59Fe-labelled ferric citrate from duodenal and ileal loops was measured, and the proportional distribution between the carcass and the washed loop measured (Expt 3).(ABSTRACT TRUNCATED AT 250 WORDS)     

Modification of vitamin A metabolism in rats fed a copper-deficient diet

The liver is the main storage site of vitamin A and copper. Inverse relationships between copper and vitamin A liver concentrations have been suggested. We have investigated the consequences of a copper-deficient diet on liver and blood vitamin A storage in Wistar rats. Animals were fed either a copper-deficient diet for 45 days from weaning, or an identical diet containing adequate amounts of copper. Concentrations of vitamin A were determined by isocratic high performance liquid chromatography using UV detection. We have observed in the liver of the rats fed a copper-deficient diet a significantly higher mean level of retinyl esters (148 +/- 37 micrograms/g of liver) and retinol (3.3 +/- 1.4 micrograms/g of liver) compared to the mean concentration of the retinyl esters (53 +/- 8.5 micrograms/g of liver) (p less than 0.01) and retinol (1.4 +/- 0.5 micrograms/g of liver) (p less than 0.01) in controls. Opposite results were observed in the serum of the group fed a copper-deficient diet as these rats had a significantly lower level of retinol (22 +/- 4 micrograms/100 ml) compared to the mean concentration in the controls (64 +/- 20 micrograms/100 ml) (p less than 0.01). These findings suggest that a copper-deficient diet may cause defective transport of vitamin A from liver to blood. This experimental model may be useful to further investigate unusual liver vitamin A and copper concentrations observed in children during various hepatobiliary diseases.     

Iron status of suckling rats as influenced by maternal diet during gestation and lactation

1. Two experiments are reported. In Expt 1, pregnant Sprague-Dawley rats (200-220 g) were given purified diets containing 35, 75, 150 or 300 mg Fe/kg throughout gestation and lactation. In Expt 2, the levels of Fe given were 250 and 300 mg/kg diet. 2. Litters were standardized at birth to contain seven pups. On day 20 of lactation blood, milk, spleen and liver were collected for Fe analysis. 3. A dietary Fe concentration of 35 mg/kg maintained maximum weight gain, food intake, liver and spleen weight, haemoglobin concentration and packed cell volume in the growing maternal rat through 20 d of lactation. Dam liver and spleen Fe concentrations were maximized between 75 and 250 mg Fe/kg diet. 4. Pups (20-d-old) nursed by dams given 35 mg Fe/kg tended to have lower body and organ weights compared to other groups. Liver and spleen Fe concentrations increased with increasing maternal dietary Fe and were significantly increased between 150 and 250 mg Fe/kg.     

Copper absorption and copper balance during consecutive periods for rats fed varying levels of dietary copper

Copper (Cu) balance and absorption were studied to determine the extent to which absorption is dependent on dietary Cu. Over 12 consecutive 5-d metabolic periods, Cu balance was determined for four groups of young growing rats (n = 8) fed modified AIN-76 diets having different levels of added Cu (2.5, 5.0, 10 or 20 micrograms/g). Among groups, mean body weights did not differ over time (P greater than 0.05). There were no significant differences among groups for liver, heart or plasma Cu. Rats in all groups were in positive Cu balance throughout the study. After consuming the experimental diets for 10 d, rats eating 10 or 20 micrograms Cu/g diet showed a more positive Cu balance than did rats in the other groups. This trend continued until d 60. For rats eating 20 micrograms Cu/g diet, balance varied significantly over time. Three test meals labeled with stable 65Cu were fed at d 10, 40 and 50, respectively. Apparent Cu absorption, as determined by fecal monitoring of 65Cu, did not change appreciably over time for rats eating 2.5 or 5.0 micrograms Cu/g diet. A test meal labeled with radioactive 67Cu was fed at d 40. For rats eating 2.5 micrograms Cu/g diet, apparent absorption was higher (31%) than that for all other groups (5.0, 23%; 10, 19%; 20, 16%; P less than 0.05). Absorption values determined by whole-body retention of 67Cu were similar to those determined by fecal monitoring of 65Cu.     

Duodenal xanthine oxidase (EC 1.2.3.2) and ferroxidase activities in the rat in relation to the increased iron absorption caused by peroral xylitol

The effect of peroral administration of xylitol on the absorption of iron and the activities of xanthine oxidase (EC 1.2.3.2) and ferroxidase in rat duodenal wall was studied. Adult male rats were given the basal diet containing 200 g xylitol/kg or the same diet containing no added carbohydrates for 8 weeks. Both feeding groups comprised twelve animals. Xylitol significantly increased serum and liver Fe concentrations with a concomitant, significant increase in the duodenal xanthine oxidase activities, but caused a marginal increase in the duodenal ferroxidase activities. In vitro, sugar alcohols reduced the binding rate of Fe to transferrin. The xylitol-induced increase of Fe absorption may involve the following mechanism: the high intraluminal xylitol concentration of the xylitol-fed rats keeps Fe in the form of a soluble complex for a prolonged period of time, due to the slow absorption of xylitol. The polyol-Fe complex in turn induces xanthine oxidase and ferroxidase formation.     

Adverse effects of high dietary iron and ascorbic acid on copper status in copper-deficient and copper-adequate rats

The effects of elevated dietary ascorbic acid and iron on copper utilization were examined. Male Sprague-Dawley rats were fed one of two levels of Cu (deficient, 0.42 microgram Cu/g, or adequate, 5.74 micrograms Cu/g), Fe (moderate, 38 micrograms Fe/g or high, 191 micrograms Fe/g), and ascorbic acid (low, 0% or high, 1% of the diet) for 20 d. High Fe decreased (p less than 0.05) Cu absorption only in Cu-deficient rats. High ascorbic acid significantly decreased tissue Cu levels in Cu-adequate rats. High Fe with ascorbic acid caused severe anemia in Cu-deficient rats and decreased plasma ceruloplasmin by 44% in Cu-adequate rats. Cu,Zn-superoxide dismutase activity in erythrocytes was decreased (p less than 0.05) by 14% during Cu deficiency but was not affected by Fe or ascorbic acid. These results may be important to individuals with high intakes of Fe and ascorbic acid.     

Dietary lead and calcium: effects on blood pressure and renal neoplasia in Wistar rats

We examined the potential of increased Ca in the diet to modify the effects of Pb on tissue metal concentrations, blood pressure and the incidence of renal tumours. We randomly assigned 48, 5-wk-old male Wistar rats to one of six treatment groups. They were fed a low (0.2%) or high (4.0%) Ca diet for 31 wk and given 0, 1.0 or 100 micrograms Pb/mL in drinking water. In the low Ca groups, increasing concentrations of Pb produced graded increases in mean blood pressure. Rats receiving 4.0% Ca had higher mean blood pressures than the animals fed the 0.2% Ca diet. The 4.0% Ca diet also caused renal and urinary bladder stones to develop in some rats. The high Ca diet did not prevent dose-dependent increases in tissue Pb accumulation, but it caused significant decreases in kidney Cu, femur Mg and Fe in kidney, liver and testis. Femur Mg and Fe and liver Fe concentrations were lowest in rats receiving 4.0% Ca and 100 micrograms Pb/mL. Precancerous and cancerous renal lesions occurred to the greatest extent in the rats receiving 100 micrograms Pb/mL and the high Ca diet. These results suggest that high dietary Ca does not protect against Pb-induced increases in blood pressure or Pb accumulation in tissues and may often produce nephrocalcinosis. In addition, high dietary Ca in the presence of Pb may increase the incidence of renal tumors.     

Iron and zinc concentrations and 59Fe retention in developing fetuses of zinc-deficient rats

Because disturbances in iron metabolism might contribute to the teratogenicity of zinc deficiency, we examined the effect of zinc deficiency on fetal iron accumulation and maternal and fetal retention of 59Fe. Pregnant rats were fed from mating a purified diet containing 0.5, 4.5 or 100 micrograms Zn/g. Laparotomies were performed on d 12, 16, 19 and 21 of gestation. Maternal blood and concepti were analyzed for zinc and iron. Additional groups of dams fed 0.5 or 100 micrograms Zn/g diet were gavaged on d 19 with a diet containing 59Fe. Six hours later maternal blood and tissues, fetuses and placentas were counted for 59Fe. Maternal plasma zinc, but not iron, concentration was affected by zinc deficiency on d 12. Embryo zinc concentration on d 12 increased with increasing maternal dietary zinc, whereas iron concentration was not different among groups. On d 16-21 plasma iron was higher in dams fed 0.5 micrograms Zn/g diet than in those fed 4.5 or 100 micrograms/g, whereas plasma zinc was lower in dams fed 0.5 or 4.5 micrograms Zn/g than in those fed 100 micrograms Zn/g diet. On d 19 zinc concentration in fetuses from dams fed 0.5 micrograms/g zinc was not different from that of those fed 4.5 micrograms/g zinc, and iron concentration was higher in the 0.5 microgram Zn/g diet group. The increase in iron concentration in zinc-deficient fetuses thus occurs too late to be involved in major structural teratogenesis. Although whole blood concentration of 59Fe was not different in zinc-deficient and control dams, zinc-deficient dams had more 59Fe in the plasma fraction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Development of anemia in copper-deficient rats fed high levels of dietary iron and sucrose

The effects of dietary carbohydrate and iron on the development of copper deficiency were examined. Male Sprague-Dawley rats (n = 48) were limit-fed one of eight diets in a 2 X 2 X 2 factorial design for 19 d. Two levels of copper (0.85 or 8.6 micrograms Cu/g diet) and iron (54 or 226 micrograms Fe/g diet) and two types of carbohydrate (sucrose or cornstarch, 65.3%) were fed. Compared with control rats, copper-deficient rats had lower hematocrits, lower ceruloplasmin levels, lower tissue levels of copper and increased hepatic iron levels. Copper-deficient rats fed sucrose had significantly lower hematocrits, lower apparent absorption of copper, lower liver iron levels and higher plasma triglyceride levels than copper-deficient rats fed cornstarch. Copper-deficient rats fed sucrose with 226 micrograms Fe/g diet had hematocrit levels that were 15% lower than all other copper-deficient levels and 23% lower than control levels. Tissue levels of copper among copper-deficient rats were not affected by the type of carbohydrate or by the level of dietary iron. These data indicate that both high iron and sucrose can affect the development of the copper deficiency.     

Both aluminum and polyphenols in green tea decoction (<Emphasis Type="Italic">Camellia sinensis</Emphasis>) affect iron status and hematological parameters in rats

Background Green tea leaves naturally contain high levels of polyphenols and aluminum (Al). Polyphenols in green tea decoction are considered to be one of the major factors responsible of low iron status. However, the effects of Al from green tea decoction on iron status and hematological parameters remained unclear. Aim of the study The objective was to investigate the Al absorption from green tea decoction and studied its influence on iron status and hematological parameters in rats. Methods During the experiment period, rats were given the experimental diet + a simple dose of Al sulfate with or without graded doses of green tea decoction (25, 50 and 100 g/l). The Al absorption was evaluated in the serum; however, iron status was evaluated by the iron concentration in the liver, kidney, spleen and femur. In addition, the hemoglobin and hematocrit were evaluated. Results Our results showed that the serum Al significantly increased between 61.5 and 342%, as tea doses-dependant. The Al sulfate significantly decreased the reserve of iron in all studied organs between 21.7 and 17% (P < 0.05). In groups receiving green tea decoction alone or Al + graded doses of tea, the reserve of iron significantly decreased in all studied organs between 59.4 and 18.5% (P < 0.01). Al alone or associated with drinking doses of tea significantly decreased hemoglobin concentration between 23.6 and 9% (P < 0.05) and hematocrit between 12.7 and 7% (P < 0.01). Conclusion Our data showed that Al from green tea decoction was more absorbed in the serum than Al sulfate. Al absorption was associated with low iron status and reduction of hemoglobin and hematocrit. Considering that Al competes with iron in different stage of erythropoiesis including transferrin binding, so we could assume that the negative effect of tea on iron status arises not only from polyphenols iron complexes but also from Al released in tea decoction.     

The effect of differences in dietary iron intake on 59Fe absorption and duodenal morphology in pregnant rats

The effect of iron intake on 59Fe absorption throughout pregnancy, and on maternal and fetal Fe status towards the end of pregnancy, was investigated in rats. The influence of pregnancy and dietary Fe on duodenal morphology was also studied. Female rats were fed on a diet containing 17 or 100 mg Fe/kg for 2 weeks before and throughout pregnancy. 59Fe absorption was measured on days 1 or 2, 8 or 9 and 17 or 18 of pregnancy, and maternal and fetal Fe status was determined on days 18 or 19. Pregnancy resulted in a fall in haemoglobin (Hb) concentration. Compared with non-pregnant counterparts, total liver Fe was reduced in the low-Fe group, but not in the high-Fe group, indicating that the fall in Hb in the high-Fe rats was not associated with an Fe-deficient state. 59Fe absorption in rats fed on both diets increased throughout pregnancy, demonstrating that Fe supplementation of the diet, to a level that prevented the development of Fe-deficiency, failed to suppress an increase in absorption. Fetal weight appeared to be an important determinant of the efficiency of Fe absorption in late pregnancy. Poor maternal Fe status was accompanied by a reduction in fetal Fe concentration but results also suggested that fetuses were partly protected from maternal Fe-deficiency. Pregnancy resulted in increased duodenal circumference and villus dimensions, whilst high dietary Fe reduced duodenal growth in both pregnant and non-pregnant animals. The relevance of this finding is discussed. It was concluded that, in rats, pregnancy per se causes an enhancement in Fe absorption and that the degree of enhancement is in part related to fetal mass.     

Beneficial influence of an indigenous low-iron diet on serum indicators of iron status in patients with chronic liver disease

The main Fe storage organ in the body is the liver. In patients with chronic liver disease, secondary Fe overload is common. Phlebotomy, often used in the West to reduce Fe overload to improve the efficacy of interferon therapy, is not socially acceptable in India. We assessed the efficacy of a low-Fe diet in reducing serum Fe levels. Nineteen patients with hepatitis B- and C-related chronic liver disease, ten with normal (< 25 mumol/l) baseline serum Fe levels (group A) and nine with high (> 25 mumol/l) serum Fe levels (group B) were included. All the subjects were advised to eat a low-Fe diet. The daily Fe intake was reduced approximately 50% by consumption of the rice-based diet. Haemoglobin, serum Fe, transferrin saturation index (TSI), ferritin and alanine transaminase (EC 2.6.1.2) levels were studied at 1 and 4 months. Dietary Fe intake and body weight were closely monitored. All patients complied with the dietary regimen and at 4 months significant (P < 0.001) reductions from baseline were seen in serum Fe (20 (SD 3) v. 12 (SD 4) mumol/l group A; 30 (SD 3) v. 19 (SD 7) mumol/l group B) and TSI (38 (SD 8) v. 23 (SD 9)% group A; 53 (SD 15) v. 34 (SD 13)%, group B) in both the groups, albeit earlier in group B subjects. Serum ferritin levels, however, reduced only in group A (112 (SD 62) v. 43 (SD 25) ng/ml, P < 0.05) and not in group B. Non-significant reductions in haemoglobin levels were seen in both groups. Alanine transaminase levels reduced significantly (P < 0.05) in both the groups (95 (SD 49) v. 44 (SD 25) IU/l, group A; 82 (SD 16) v. 51 (SD 14) IU/l group B). Thus, a low-Fe diet results in significant reductions in serum Fe and TSI levels, irrespective of baseline Fe levels. This diet should be evaluated to improve the efficacy of interferon therapy in patients with hepatitis B- and C-related chronic liver disease.