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1.
The effects of dietary zinc deficiency (ZD) on the composition and metabolism of the fatty acyl chains of phospholipids in
rat liver were investigated with a fat-free diet. The levels of (n−9) fatty acids such as 18∶1 and 20∶3(n−9) in liver phospholipids (PL) were significantly lower in ZD-rats (19.4% and 5.4%, respectively) than in PF-rats (25.2 and
8.3%). On the other hand, the level of (n−6) acids such as 18∶2 and 20∶4 were higher in ZD-rats (3.3 and 19.1%, respectively) than in PF-rats (2.1 and 14.9%).
In order to study the metabolism of fatty acids in vivo,14C-18∶0 or14C-18∶2 was intravenously injected, and then the conversion to the respective metabolite was examined. After the injection
of14C-18∶0, the radioactivity was found in 18∶0 (49.3% of the total), 18∶1 (33.2%), and 20∶3 (n−9) (9.1%) in liver PL in PF-rats at 24h. In ZD-rats, the radioactivity was dramatically lower in 18∶1 (23.5%) and 20∶ (n−9) (3.6%), suggesting that the conversion of 18∶0 to 18∶1 and 20∶3 (n−9) was strongly inhibited in ZD-rats. When14C-18∶2 was injected, the radioactivity was mainly found in 18∶2, 20∶3(n−6), and 20∶4. The radioactivity in 20∶4 in ZD-rats was slightly higher than that in control rats.
These results indicate that zinc deficiency affects the fatty acid metabolism in liver, in particular, it causes a reduction
in δ9 desaturase activity, when rats are fed a fat-free diet. 相似文献
2.
Yan G. Zorbas Yuri N. Yaroshenko Nikolai K. Kuznetsov Alexei L. Ivamov 《Biological trace element research》1997,60(1-2):101-113
The objective of this investigation was to evaluate the effect of 47 mg zinc supplementation on deficiency of zinc in rats
during 98 d of restriction of motor activity (hypokinesia), which appeared by higher plasma zinc concentration.
One Hundred 13-week-old Sprague-Dawley male rats weighing 360–390 g were used to perform the studies: They were equally divided
into four groups: 1. Unsupplemented control animals (UCA); 2. Unsupplemented hypokinetic animals (UHA); 3. Supplemented control
animals (SCA); and 4. Supplemented hypokinetic animals (SHA). For the simulation of the effect of hypokinesia (HK), the UHA
and SHA were kept in small individual cages made of wood, which restricted their movements in all directions without hindering
food and water intake. The SCA and SHA received daily with their food an additional amount of zinc.
Before and during the experimental period of 98 d, plasma, urinary and fecal zinc, balance of zinc, food intake, and body
weight were determined at different intervals. In the SHA and UHA, the concentration of zinc in plasma, and the elimination
of zinc in urine and feces increased significantly when compared with the SCA and UCA, whereas the balance of zinc was negative.
The body weight and food intake decreased significantly in the SHA and UHA when compared with the SCA and UCA. The increased
plasma concentration of zinc in both the SHA and UHA groups was in contrast to the observed hypozincnemia during prolonged
immobilization as during prolonged hospitalization. This reaction suggests that there may be some other mechanisms that are
affecting the process of control and regulation of zinc metabolism during prolonged HK.
It was concluded that exposure to prolonged restriction of motor activity of rats induces significant increases in plasma
concentration, fecal and urinary elimination of zinc in the presence of negative zinc balance and regardless the daily intake
of large amounts of zinc with their food, leading to zinc deficiency. 相似文献
3.
Five groups of individually housed albino rats (n=7, initial average weight=48 g) were fed diets based on egg albumen and cornstarch (basal diet 8.2 g Ca, 6.0 g P, 0.7 g Mg,
225 mg Zn, 150 mg Fe, 60 mg Mn, 8 mg Cu, and 5 mg Cd) over a 4-wk period. Group I (control) was fed the basal diet free of
phytic acid (PA). In groups II, III, IV, and V, cornstarch was replaced by 3.5, 7.0, 10.5, and 14.0 g sodium phytate/kg diet,
respectively. Daily gain, feed efficiency, Zn status (Zn in plasma, femur, testes, liver and kidneys, activity of the plasma
alkaline phosphatase) and apparent absorption of Zn, Fe, Cu, and Mn remained unchanged by the different dietary treatments.
PA decreased apparent Mg absorption significantly and apparent absorption of Ca in tendency. Increasing the amount of phytate
caused a corresponding enhancement of amount of the digestible P. Cd accumulation in the liver was not significantly altered,
and kidney Cd accumulation slightly increased owing to PA. In conclusion, it was shown that under conditions of high dietary
Zn, PA had only little effect on the carryover of Cd in growing rats. 相似文献
4.
This study was designed to determine the time dependent protective effects of zinc sulfate on the serum and liver marker enzymes
along with elemental profile in protein deficient Sprauge Dawley (S.D.) female rats. Zinc sulfate in the dose of 227 mg/l
in drinking water was administrated to normal control as well as protein deficient rats for a total duration of 8 weeks. The
effects of different treatments were studied on enzymes like alkaline phosphatase (ALP), aspartate aminotransferases (AST)
and alanine aminotransferases (ALT) in rat serum at different time intervals of 1, 2, 4 and 8 weeks and in the rat liver at
the end of study. The status of different essential elements in liver was also studied. The serum ALP activity got significantly
depressed when estimated at the intervals of 4 and 8 weeks. Activity of serum ALT was significantly increased after 4 weeks
interval in protein deficient rats and the increasing trend continued upto 8 weeks of protein deficiency. On the other hand,
activity of AST showed a significant increase just after 2 weeks and activity continued to be increased up to 8 weeks. Moreover
activities of all the hepato marker enzymes showed a significant increase in liver of protein deficient rats. Interestingly,
supplementation of Zn to protein deficient rats helped in regulating the altered activities of ALP, AST and ALT both in serum
and liver. However, zinc treatment alone to normal rats did not indicate any significant change in the activities of all the
enzymes in liver as well serum except at the interval of 2 weeks where a marginal increase in the activity of AST was seen.
It has also been observed that concentrations of zinc, copper, iron and selenium were found to be decreased significantly
in protein deficient animals. However, the levels of these elements came back to within normal limits when zinc was administrated
to protein deficient rats.
Published online December 2004 相似文献
5.
The relationship between magnesium (Mg) and zinc (Zn) in soft tissues and bone of rats was studied after administration of unbalanced mineral diets. Minerals and metals in soft tissues and bone were determined using inductively coupled plasma emission spectrometry (ICP). There were significant positive correlations between serum Zn and Mg levels, between serum Zn and Zn content of soft tissues and bone, and between serum Mg levels and Zn content of bone and soft tissues in rats fed unbalanced mineral diets. A significant positive correlation was also found between Zn and Mg content in the lumbar spine and femoral bone of rats. It appears that altered bone mineralization induced by unbalanced mineral diets leads to mobilization of Mg and Zn from rat bones in similar ways. 相似文献
6.
The effects of zinc deficiency and supplementation on plasma leptin levels were studied in Sprague-Dawley rats. After 6 wk
on a zinc-deficient diet containing 0.65 ppm Zn/g, the mean body weight was significantly lower than that of normal or zinc-supplemented
rats, which showed no difference among them. The plasma leptin and zinc levels were lowest in zinc-deficient animals and highest
in those that received a normal diet and daily intraperitioneal injections of 3 mg Zn/kg. These results indicate that zinc
deficiency leads to a significant inhibition in plasma leptin levels, whereas zinc supplementation significantly increases
plasma leptin. 相似文献
7.
Mineral and trace element interactions were studied in a balance trial with rats. Calcium, copper, and zinc were supplied
to a rapeseed meal diet in a factorial design. Animals were fedad libitum, and absorption, excretion, and retention of the elements were evaluated either as fractions of total intake or in relation
to nitrogen retention to account for differences in food intake and lean body mass increment. The intrinsic content of minerals
and trace elements was sufficient to support growth at a rate that could be expected from the rapeseed protein quality. However,
when calcium was included in the diet, the intrinsic dietary level of zinc appeared to be limiting, despite the fact that
the zinc level was twice the recommended level. Additional zinc supply reversed growth impairment. This calcium-zinc interaction
is believed to be owing to the formation of phytate complexes. Calcium addition influenced the calcium, phosphorus, magnesium,
zinc, and iron—but not the copper—balances. The addition of calcium reduced the availability of the intrinsic zinc, whereas
no effect was seen in the zinc-fortified groups. The availability of intrinsic copper was in a similar way significantly impaired
by addition of dietary zinc, where-as copper-supplied groups were unaffected by zinc addition. Intrinsic iron availability
was also dependent upon zinc addition, although in a more ambigouus way. Thus, addition of extrinsic minerals to a diet high
in phytate can result in significant impairments of growth and mineral utilization. 相似文献
8.
Sun JY Jing MY Weng XY Fu LJ Xu ZR Zi NT Wang JF 《Biological trace element research》2005,107(2):153-165
Zinc (Zn) is an essential nutrient that is required in humans and animals for many physiological functions, including immune
and antioxidant function, growth, and reproduction. The present study was performed to investigate the effects of three Zn
levels, including Zn adequate (35.94 mg/kg, as a control), Zn deficiency (3.15 mg/kg), and Zn overload (347.50 mg/kg) in growing
male rats for 6 wk. This allowed for evaluation of the effects that these Zn levels might have on body weight, organ weight,
enzymes activities, and tissues concentrations of Zn and Cu. The results showed that Zn deficiency has negative effects on
growth, organ weight, and biological parameters such as alkaline phosphatase (ALP) and Cu−Zn superoxide dismutase (Cu−Zn SOD)
activities, whereas Zn overload played an effective role in promoting growth, improving the developments of organs and enhancing
immune system. Hepatic metallothionein (MT) concentration showed an identical increase tendency in rats fed both Zn-deficient
and Zn-overload diets. The actual mechanism of reduction of Cu concentration of jejunum in rats fed a Zn-overload diet might
involve the modulation or inhibition of a Cu transporter protein by Zn and not by the induction of MT. 相似文献
9.
Colin L. White 《Biological trace element research》1988,17(1):175-187
Body composition and the levels of some plasma metabolites were measured in zinc deficient and control rats with the aim of
assessing the nature of the metabolic defects resulting from zinc deficiency. Two experiments, lasting 15 and 20 d, were carried
out using 52 immature rats. Zinc deficient animals were fed a diet of 1–2 mg Zn/kg. Pair fed andad libitum control rats received the same diet with 100 ppm zinc added to the drinking water. Feed intake and growth rate were measured,
and the carcasses were analyzed for protein, fat, and ash. In each experiment, a group of rats were killed on d 1 to provide
pretreatment values and to allow for estimates of net deposition of carcass components. Lactate, urea, and zinc were assayed
in plasma, as well as zinc concentration in carcasses and liver.
The main effect of zinc deficiency was to reduce feed intake and efficiency of feed conversion, resulting in a reduced proportion
of carcass wat because of the reduced feed efficiency, zinc deficiencyper se resulted in an increase in the proportion of fat in the carcass. Plasma lactate concentration was unchanged, but urea concentration
increased in both pair fed and zinc deficient rats relative toad libitum fed control animals. The results indicate that a defect in protein synthesis and an increase in energy expenditure, perhaps
resulting from increased protein turnover, underlies the reduced growth and efficiency of feed conversion of zinc deficiency. 相似文献
10.
ObjectivesZinc, which is found in high concentrations in the β-cells of the pancreas, is also a critical component for the endocrine functions of the pancreas. SLC30A8/ZnT8 is the carrier protein responsible for the transport of zinc from the cytoplasm to the insulin granules. The aim of this study was to investigate how dietary zinc status affects pancreatic beta cell activation and ZnT8 levels in infant male rats born to zinc-deficient mothers.MethodsThe study was performed on male pups born to mothers fed a zinc-deficient diet. A total of 40 male rats were divided into 4 equal groups. Group 1: In addition to maternal zinc deficiency, this group was fed a zinc-deficient diet. Group 2: In addition to maternal zinc deficiency, this group was fed a standard diet. Group 3: In addition to maternal zinc deficiency, this group was fed a standard diet and received additional zinc supplementation. Group 4: Control group. Pancreas ZnT8 levels were determined by ELISA method and insulin-positive cell ratios in β-cells by immunohistochemistry.ResultsThe highest pancreatic ZnT8 levels and anti-insulin positive cell ratios in the current study were obtained in Group 3 and Group 4. In our study, the lowest pancreatic ZnT8 levels were obtained in Group 1 and Group 2, and the lowest pancreatic anti-insulin positive cell ratios were obtained in Group 1.ConclusionThe results of the present study; in rats fed a zinc-deficient diet after maternal zinc deficiency has been established shows that ZnT8 levels and anti-insulin positive cell ratios in pancreatic tissue, which is significantly suppressed, reach control values with intraperitoneal zinc supplementation. 相似文献
11.
Salgueiro J Leonardi N Zubillaga M Weill R Goldman C Calmanovici G Barrado A Sarrasague MM Boccio J 《Biological trace element research》2005,104(3):261-267
The aim of the study was to determine the relative bioavailability of zinc gluconate stabilized with glycine in a Petit Suisse
cheese from an infant dessert. Weight gain and bone zinc content were the nutritional responses evaluated for the diets of
different zinc content: 2 ppm (basal) and 5, 10, and 30 ppm from zinc gluconate stabilized with glycine and zinc sulfate.
Nonlinear regression analysis of the fitted curves for weight gain determined a relative zinc bioavailability of 100% for
the Y
max ratio and 96% for Y
max/t
1/2 ratio for zinc gluconate stabilized with glycine (R
2=0.7996 for zinc sulfate and 0.8665 for zinc gluconate stabilized with glycine). The slope ratio analysis from linear regression
of femur zinc determined a relative zinc bioavailability of 93% for zinc gluconate stabilized with glycine (R
2=0.8693 for zinc sulfate and 0.8307 for zinc gluconate stabilized with glycine). Zinc gluconate stabilized with glycine has
similar bioavailability as zinc sulfate in a Petit Suisse cheese nutritional matrix, with the advantage that the stabilized
compound does not modify the sensorial characteristics of the fortified cheese. 相似文献
12.
The extracellular concentration of glutamate in the hippocampus is increased by hippocampal perfusion with CaEDTA, a membrane-impermeable zinc chelator, suggesting that the activity of glutamatergic neurons in the hippocampus are influenced by the extracellular concentrations of zinc. In the present study, the relationship between the extracellular concentrations of zinc and mossy fiber activity in the hippocampus was examined in mice and rats fed a zinc-deficient diet for 4 weeks. Timm's stain, by which histochemically reactive zinc in the presynaptic vesicles is detected, was attenuated in the hippocampus in zinc deficiency. The extracellular signal of ZnAF-2, a membrane-impermeable zinc indicator, was also lower in the hippocampal CA3, suggesting that the basal extracellular concentrations of zinc are lower maintained in zinc deficiency. To check mossy fiber activity after 4-week zinc deprivation, the decrease in the signal of FM4-64, an indicator of presynaptic activity (exocytosis), at mossy fiber synapses was measured under the condition of spontaneous depolarization. The decrease was significantly facilitated by zinc deficiency, suggesting that the basal exocytosis at mossy fiber synapses is enhanced by zinc deficiency. On the other hand, the increase in anxiety-like behavior was observed in the open-field test after 4-week zinc deprivation. The present study demonstrates that the decrease in the basal extracellular concentrations of zinc may be linked to the enhancement of the basal mossy fiber activity in zinc deficiency. This decrease seems to be also involved in neuropsychological behavior in zinc deficiency. 相似文献
13.
Effects of maternal marginal zinc deficiency on myelin protein profiles in the suckling rat and infant rhesus monkey 总被引:1,自引:0,他引:1
Hueyjiuan Liu Patricia I. Oteiza M. Eric Gershwin Mari S. Golub Carl L. Keen 《Biological trace element research》1992,34(1):55-66
In the current study, the effects of marginal Zn deficiency on myelin protein profiles in neonatal rats and rhesus monkeys
were investigated. Following mating, rats were fed a Zn-adequate diet,ad libitum (50 μg Zn/g; 50 Zn AL), or a marginal Zn diet (10 μg Zn/g) from day 0 (10 Zn d0) or day 14 (10 Zn d14) of gestation to day
20 postnatal. An additional group of dams was restricted-fed the control diet to the food intake of the 10 Zn d0 group (50
Zn RF). Day 20 pup plasma and liver Zn concentrations in the 10 Zn groups were lower than in the 50 Zn groups. In a parallel
experiment, rhesus monkeys were fed a Zn-adequatead libitum diet (100 μg Zn/g) or a marginal Zn diet (4 μg Zn/g diet; MZD) throughout gestation and lactation. Day 30 monkey infant plasma
and liver Zn levels were similar in the MZD and control groups. Rat brain and monkey brain cortex weights were similar among
the dietary groups. The amount of myelin recovered (mg protein/g brain) from day 20 rat pups from the 10 Zn groups was lower
than that recovered from the 50 Zn rat pups. Myelin recovery from the MZD and control monkey infants was similar. When myelin
protein profiles were characterized, it was found that the percentages of high-molecular-weight (HMW) proteins and Wolfgram
protein were higher, whereas the percentages of small and large basic proteins were lower in myelin from the 10 Zn d0 and
50 Zn RF pups compared to the distribution in the 50 Zn AL rat pups. Results for the 10 Zn d0 and 10 Zn d14 pups were similar
for all of the parameters studied. The percentage of HMW proteins was higher and that of basic protein lower in myelin from
MZD monkey infants compared to the percentage of these proteins in myelin from controls. Although the interpretation of the
rat data is complicated because of the anorexia associated with the Zn deficiency, the observed changes in monkey myelin protein
profiles provide strong evidence that maternal Zn deficiency affects myelination in the offspring. 相似文献
14.
O'Dell et al. reported that rectal temperature was decreased by zinc deficiency in rats. However, it is not known whether
a combined deficiency of zinc and iron affects rectal temperature. Forty 4-wk-old male Sprague-Dawley rats were assigned into
four dietary treatment groups of 10 rats each for the 4-wk study: zinc-deficient group (4.5 mg Zn and 35 mg Fe/kg diet; −Zn),
iron-deficient group (30 mg Zn/kg diet, no supplemental iron; −Fe), zinc/iron-deficient group (4.5 mg Zn/kg diet, no supplemental
iron; −Zn−Fe), and control group (AIN-93G; Cont). At d 24–27, the rectal temperature was determined. The rectal temperature
of the −Zn group was significantly lower than the Cont group. The rectal temperature of the −Zn−Fe group was similar to that
of the Cont group, although thyroid-stimulating hormone and total thyroxin concentrations were the lowest in the −Zn−Fe group
among all groups. The pattern of the plasma nitrate/nitrite concentrations across groups was similar to rectal temperature.
Although observation of the rectal temperature is not conclusive, the balance between zinc and iron intake seems to determine
the body temperature set point. These results suggest that the thermogenic effect of thyroid hormones is not throught to influence
the paradoxical maintenance of rectal temperature in combined deficiency of zinc and iron. 相似文献
15.
The aim of this study was to investigate how zinc deficiency and supplementation affects lipid peroxidation in the renal tissue
in ovariectomized rats. Four study groups were formed with 10 Spraque-Dawley rats each. Two of the groups served as normal
and ovariectomized controls; the other two were ovariectomized rats that were zinc deficient and zinc supplemented, respectively.
The zinc-deficient ovariectomized rats showed greater renal and plasma lipid peroxidation, as indicated by higher malondialdehyde
levels than all other groups (p<0.05). These values were higher in the ovariectomized controls than those of the normal controls and of the ovariectomized,
zinc-supplemented groups (p<0.05), which, in, turn, showed no significant differences of their respective renal and plasma malondialdehyde values.
The renal and erythrocyte glutathione levels in the zinc-supplemented rats were higher than those in all other groups (p<0.05). The zinc-deficient group had the lowest renal and erythrocyte glutathione levels (p<0.05). The renal tissue zinc levels in the ovariectomized rats were higher than those in the zinc-deficient animals, but
lower than in the normal controls and zincsupplemented rats (p<0.05). The zinc-supplemented animals had the highest renal tissue zinc levels (p<0.05).
The results of this study suggest that zinc deficiency increases renal tissue damage in ovariectomized rats and that zinc
supplementation can be used to prevent this condition. 相似文献
16.
17.
Salgueiro MJ Torti H Meseri E Weill R Orlandini J Urriza R Zubillaga M Janjetic M Barrado A Boccio J 《Biological trace element research》2006,110(1):73-77
The aim of the present study was to assess dietary zinc effects on femur weight and mineral content in growing rats. For this
purpose, 70 weanling Sprague-Dawley rats were divided into four groups. Each group was subject to a diet containing 2 (BZ),
5 (DZ), 10 (MZ), and 30 (CZ) ppm zinc. The calcium and magnesium content in all diets was 5 g/kg and 507 mg/kg, respectively.
The animals were kept on this regime for 28 d and then sacrificed and their femurs were removed for analysis using atomic
absorption spectrophotometry.
The weights of the BZ and DZ groups were significantly different from the MZ and CZ groups (38.5±10.5, 89.9±13.7, 118.6±13.6
and 134±19.9 g, p<0.01) respectively. There were no differences between the MZ and CZ groups. Femur weight also varied with dietary zinc, as
it was significantly different among all groups (BZ, 265±49 mg; DZ, 380±40 mg; MZ, 452±54 mg; CZ, 735±66 mg; p<0.01). The femur zinc content varied with diets, following a different pattern than the above parameters. Femur zinc from
the BZ group (51.5±5.4 ppm) was significantly different from the MZ and CZ groups (115.9±14.2 and 175.0±13.5 ppm, respectively),
whereas the DZ group (62.5±11.3 ppm) did not differ from the other three groups. The femur content of calcium (BZ, 83.2±9.8
mg/g; DZ, 88.0±9.2 mg/g; MZ, 90.2±13.6 mg/g; CZ, 83.1±14.7 mg/g) and magnesium (BZ, 1.82±0.13 mg/g; DZ, 1.98±0.09 mg/g; MZ,
1.93±14 mg/g; CZ, 1.83±0.19 mg/g) were not significantly different among the groups, nor was the calcium-magnesium ratio.
These results suggest that although dietary zinc deficiency retards growth and causes bone fragility, bone deposition of calcium
and magnesium and its ratio are not affected. 相似文献
18.
Salgueiro J Leonardi N Zubillaga M Weill R Goldman C Calmanovici G Barrado A Sarrasague MM Boccio J 《Biological trace element research》2005,104(3):269-273
Fortification of a Petit Suisse cheese with zinc sulfate and zinc gluconate stabilized with glycine was used as a tool to
overcome zinc-deficiency effects on total-body growth and skeletal growth. Animals were divided in 4 groups of 10 rats: basal
(B), control (C), depletion-repletion 1 (DR1), and depletion-repletion 2 (DR2). These four groups were fed with four diets:
basal (2 ppm Zn), control (30 ppm Zn), DR1, and DR2; they received a basal diet for 14 d and a control diet for the other
14 d of the experiment, using zinc sulfate for DR1 and zinc gluconate stabilized with glycine for DR2. After 28 d of the experiment,
total-body weight and weight gain of the control and DR1 and DR2 animals were not statistically different (p<0.05), Femur weight and femur zinc content of DR1 and DR2 did not achieve the values of control animals (p<0.05), but they were higher than that of basal animals. Our results show that restoration of dietary zinc levels by means
of food fortification normalized weight gain, as an indicator of total-body growth, and presented a trend to normalize bone
weight, as a marker of skeletal growth, in young rats and independently of the zinc source used. 相似文献
19.
比较不同频率的正弦交变电磁场对SD青年大鼠骨密度及骨形态计量指标的影响,筛选可有效提升大鼠骨密度的频率参数。将32只8周龄SD雌性大鼠随机分为4组:对照组、15 Hz组、30 Hz组、45 Hz组;除对照组外,实验组大鼠每天都给予相应频率的1.8 m T正弦交变电磁场干预,干预时间为90 min。磁场干预8周后,双能X射线骨密度仪检测大鼠全身骨密度、右侧股骨骨密度和椎骨骨密度,ELISA分析血清中骨形成与骨吸收生化指标的含量,右侧胫骨进行荧光间距测量与骨形态计量分析。相比于对照组,15 Hz组、45 Hz组大鼠的全身骨密度、股骨骨密度、椎骨骨密度均明显升高(P0.05),血清中骨钙素与骨保护素含量也显著提升(P0.05);实验组大鼠的胫骨双荧光间距与骨组织静态参数均高于对照组(P0.05)。结果表明,15 Hz、45 Hz正弦交变电磁场可有效提升青年大鼠的骨密度,从而可预防骨质疏松的发生。 相似文献